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HomeMy WebLinkAboutBOARD STANDING COMMITTEES - 11082021 - TWIC Agenda Pkt (6)       TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE November 8, 2021 9:00 A.M. 1025 Escobar St., Martinez To slow the spread of COVID-19, in lieu of a public gathering, the Transportation, Water and Infrastructure meetings will be remote until further notice and accessible via link to all members of the public, as permitted by the Governor's Executive Order N29-20. Supervisor Candace Andersen, Chair Supervisor Diane Burgis, Vice Chair Agenda Items: Items may be taken out of order based on the business of the day and preference of the Committee. When: Nov 8, 2021 09:00 AM Pacific Time (US and Canada) Please click the link below to join the zoom meeting: https://cccounty-us.zoom.us/NovemberTWIC Passcode: 014536 Or Telephone, dial: USA 214 765 0478 US Toll USA 888 278 0254 US Toll-free Conference code: 198675         1.Introductions   2.Public comment on any item under the jurisdiction of the Committee and not on this agenda (speakers may be limited to three minutes).   3. Administrative Items, if applicable. (John Cunningham, Department of Conservation and Development)   4. REVIEW record of meeting for October 11, 2021, Transportation, Water and Infrastructure Committee Meeting. This record was prepared pursuant to the Better Government Ordinance 95-6, Article 25-205 (d) of the Contra Costa County Ordinance Code. Any handouts or printed copies of testimony distributed at the meeting will be attached to this meeting record. (John Cunningham, Department of Conservation and Development)   5. RECEIVE update on Senate Bill 743 (“SB 743”) implementation and California Environmental Quality Act (“CEQA”) Vehicle Miles Traveled. (Jamar Stamps, Department of Conservation and Development)   6. RECEIVE report on the adoption of the East Contra Costa Groundwater Sustainability Plan to implement sustainable groundwater management in the East Contra Costa Subbasin within Contra Costa County. (Ryan Hernandez, Department of Conservation and Development Water Agency)   7. RECEIVE the status report on the Letter of Understanding (LOU) for the maintenance of PG&E streetlights in Contra Costa County and MONITOR its implementation by PG&E. (Rochelle Johnson, Department of Public Works)   8. ACCEPT the draft of the Final Vision Zero Report dated October 2021, and DIRECT Public Works staff, on behalf of the County, to incorporate comments and present to the full Board of Supervisors. (Craig Standafer and Jerry Fahy, Department of Public Works)   9. RECEIVE and consider public comments on the draft Flood Control Capital Improvement Plan for fiscal years 2021/2022 to 2027/2028 (Plan), ACCEPT the Plan, and RECOMMEND the Board of Supervisors, as the governing board of the Contra Costa County Flood Control and Water Conservation District, adopt the Plan. (Gus Amirzehni, Department of Public Works)   10. CONSIDER report on Local, State, Regional, and Federal Transportation Related Legislative Issues and take ACTION as appropriate. (John Cunningham, Department of Conservation and Development)   11. RECEIVE Communication, News, Miscellaneous Items of Interest to the Committee and DIRECT staff as appropriate. (John Cunningham, Department of Conservation and Development)   12.The next meeting is currently scheduled for Monday, December 13, 2021.   13.Adjourn   The Transportation, Water & Infrastructure Committee (TWIC) will provide reasonable accommodations for persons with disabilities planning to attend TWIC meetings. Contact the staff person listed below at least 72 hours before the meeting. Any disclosable public records related to an open session item on a regular meeting agenda and distributed by the County to a majority of members of the TWIC less than 96 hours prior to that meeting are available for public inspection at the County Department of Conservation and Development, 30 Muir Road, Martinez during normal business hours. Public comment may be submitted via electronic mail on agenda items at least one full work day Public comment may be submitted via electronic mail on agenda items at least one full work day prior to the published meeting time. For Additional Information Contact: John Cunningham, Committee Staff Phone (925) 655-2915, Fax (925) 655-2750 john.cunningham@dcd.cccounty.us Glossary of Acronyms, Abbreviations, and other Terms (in alphabetical order): Contra Costa County has a policy of making limited use of acronyms, abbreviations, and industry-specific language in meetings of its Board of Supervisors and Committees. Following is a list of commonly used abbreviations that may appear in presentations and written materials at meetings of the Transportation, Water and Infrastructure Committee: AB Assembly Bill ABAG Association of Bay Area Governments ACA Assembly Constitutional Amendment ADA Americans with Disabilities Act of 1990 ALUC Airport Land Use Commission AOB Area of Benefit BAAQMD Bay Area Air Quality Management District BART Bay Area Rapid Transit District BATA Bay Area Toll Authority BCDC Bay Conservation & Development Commission BDCP Bay-Delta Conservation Plan BGO Better Government Ordinance (Contra Costa County) BOS Board of Supervisors CALTRANS California Department of Transportation CalWIN California Works Information Network CalWORKS California Work Opportunity and Responsibility to Kids CAER Community Awareness Emergency Response CAO County Administrative Officer or Office CCTA Contra Costa Transportation Authority CCWD Contra Costa Water District CDBG Community Development Block Grant CEQA California Environmental Quality Act CFS Cubic Feet per Second (of water) CPI Consumer Price Index CSA County Service Area CSAC California State Association of Counties CTC California Transportation Commission DCC Delta Counties Coalition DCD Contra Costa County Dept. of Conservation & Development DPC Delta Protection Commission DSC Delta Stewardship Council DWR California Department of Water Resources EBMUD East Bay Municipal Utility District EIR Environmental Impact Report (a state requirement) EIS Environmental Impact Statement (a federal requirement) EPA Environmental Protection Agency FAA Federal Aviation Administration FEMA Federal Emergency Management Agency FTE Full Time Equivalent FY Fiscal Year GHAD Geologic Hazard Abatement District GIS Geographic Information System HBRR Highway Bridge Replacement and Rehabilitation HOT High-Occupancy/Toll HOV High-Occupancy-Vehicle HSD Contra Costa County Health Services Department HUD United States Department of Housing and Urban Development IPM Integrated Pest Management ISO Industrial Safety Ordinance JPA/JEPA Joint (Exercise of) Powers Authority or Agreement Lamorinda Lafayette-Moraga-Orinda Area LAFCo Local Agency Formation Commission LCC League of California Cities LTMS Long-Term Management Strategy MAC Municipal Advisory Council MAF Million Acre Feet (of water) MBE Minority Business Enterprise MOA Memorandum of Agreement MOE Maintenance of Effort MOU Memorandum of Understanding MTC Metropolitan Transportation Commission NACo National Association of Counties NEPA National Environmental Protection Act OES-EOC Office of Emergency Services-Emergency Operations Center PDA Priority Development Area PWD Contra Costa County Public Works Department RCRC Regional Council of Rural Counties RDA Redevelopment Agency or Area RFI Request For Information RFP Request For Proposals RFQ Request For Qualifications SB Senate Bill SBE Small Business Enterprise SR2S Safe Routes to Schools STIP State Transportation Improvement Program SWAT Southwest Area Transportation Committee TRANSPAC Transportation Partnership & Cooperation (Central) TRANSPLAN Transportation Planning Committee (East County) TWIC Transportation, Water and Infrastructure Committee USACE United States Army Corps of Engineers WBE Women-Owned Business Enterprise WCCTAC West Contra Costa Transportation Advisory Committee WETA Water Emergency Transportation Authority WRDA Water Resources Development Act TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE 3. Meeting Date:11/08/2021   Subject:Administrative Items, if applicable.  Department:Conservation & Development Referral No.: N/A   Referral Name: N/A  Presenter: John Cunningham, DCD Contact: John Cunningham (925)655-2915 Referral History: This is an Administrative Item of the Committee. Referral Update: Staff will review any items related to the conduct of Committee business. Recommendation(s)/Next Step(s): CONSIDER Administrative items and Take ACTION as appropriate. Fiscal Impact (if any): N/A Attachments No file(s) attached. TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE 4. Meeting Date:11/08/2021   Subject:REVIEW record of meeting for October 11, 2021, Transportation, Water and Infrastructure Meeting. Submitted For: TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE,  Department:Conservation & Development Referral No.: N/A   Referral Name: N/A  Presenter: John Cunningham, DCD Contact: John Cunningham (925)655-2915 Referral History: County Ordinance (Better Government Ordinance 95-6, Article 25-205, [d]) requires that each County Body keep a record of its meetings. Though the record need not be verbatim, it must accurately reflect the agenda and the decisions made in the meeting. Referral Update: Any handouts or printed copies of testimony distributed at the meeting will be attached to this meeting record. Links to the agenda and minutes will be available at the TWI Committee web page: http://www.cccounty.us/4327/Transportation-Water-Infrastructure Recommendation(s)/Next Step(s): Staff recommends approval of the attached Record of Action for the October 11, 2021, Committee Meeting with any necessary corrections. Fiscal Impact (if any): N/A Attachments October TWIC Minutes D R A F T TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE RECORD OF ACTION FOR October 11, 2021   Supervisor Candace Andersen, Chair Supervisor Diane Burgis , Vice Chair    Present: Candace Andersen, Chair      Diane Burgis, Vice Chair    Staff Present: John Cunningham, Conservation and Development  Attendees:Mark Watts, Shirley Krohn, Debbie Toth, Jamar Stamps, Jerry Fahy             1.Introductions   2.Public comment on any item under the jurisdiction of the Committee and not on this agenda (speakers may be limited to three minutes).    No public comment.   3.CONSIDER Administrative items and Take ACTION as appropriate.      The Committee and staff discussed the resumption of in-person meetings. The committee advised staff that the November meeting would be on zoom.   4.Staff recommends approval of the attached Record of Action for the September 13, 2021, Committee Meeting with any necessary corrections.       The Committee unanimously APPROVED the meeting record.   5.CONSIDER the proposed Caltrans Sustainable Communities Planning Grant candidate projects, REVISE as appropriate, FORWARD to the full Board of Supervisors for approval, and/or DIRECT staff as appropriate.       The Committee unanimously APPROVED the recommendations,  The Committee unanimously APPROVED the recommendations, discussion included the need to identify funding for capital projects in the Iron Horse corridor.   6.CONSIDER report on Local, Regional, State, and Federal Transportation Related Legislative Issues and take ACTION as appropriate.       The Committee RECEIVED the report, relative to the accessible transportation legislative proposal from the California Senior Legislature the Committee supported the County continuing to provide assistance for the effort given the consistency with the adopted State Legislative Platform. Shirley Krohn (CA Sr. Legislature) and Debbie Toth (Choice in Aging) both spoke in support of the legislative proposal.   7.The next meeting is currently scheduled for Monday, November 8, 2021.   8.Adjourn      For Additional Information Contact:  John Cunningham, Committee Staff Phone (925) 674-7833, Fax (925) 674-7250 john.cunningham@dcd.cccounty.us TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE 5. Meeting Date:11/08/2021   Subject:RECEIVE update on California Environmental Quality Act (“CEQA”) Vehicle Miles Traveled. Submitted For: TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE,  Department:Conservation & Development Referral No.: 1   Referral Name: Review legislative matters on transportation, water, and infrastructure.  Presenter: Jamar Stamps, DCD Contact: Jamar Stamps, (925) 655-2917  Referral History: December 2019, County staff provided an update on the County's Senate Bill ("SB") 743 implementation, including and schedule for developing California Environmental Quality Act ("CEQA") policies for transportation impacts.  Referral Update: Background In 2013, Governor Brown signed Senate Bill (“SB”) 743 (Steinberg), which creates a process to change the way that transportation impacts are analyzed under California Environmental Quality Act (“CEQA”). Specifically, SB 743 changed the way that transportation impacts are analyzed under CEQA. Automobile delay metrics (i.e., level of service or “LOS”) will no longer be considered a significant impact under CEQA and the Governor’s Office of Planning and Research (“OPR”) recommends that jurisdictions instead use the Vehicle Miles Traveled (“VMT”) metric. OPR released a “Technical Advisory” (2018) containing methodologies and thresholds for VMT, but the Technical Advisory is not regulatory, only advisory. OPR allows jurisdictions to retain their congestion-based standards (i.e., LOS) in general plans and for project planning purposes, but these standards will not be CEQA considerations. Developers in some cases are required to perform two different traffic analyses. Staff will update General Plan policies to accommodate congestion-based standards. What is VMT? VMT is a measure of the total amount of (miles) vehicular travel. For example, one vehicle traveling ten miles would equal 10 VMT. Four vehicles traveling ten miles would equal 40 VMT. Typically, development located at greater distance from other land uses or in areas with few transportation options generates more vehicle trips and trips of greater length (and therefore more VMT) than development located in close proximity to other uses or in areas with many transportation choices. California Office of Planning and Research (“OPR”) December 2018, OPR adopted the Technical Advisory on Evaluating Transportation Impacts in CEQA. OPR’s Technical Advisory contains recommendations regarding assessment of VMT, thresholds of significance, and mitigation measures as a resource for the public to use at their discretion. OPR indicates their guidance is only advisory, not mandatory. County staff has relied on this guidance, as well as information from various other sources (e.g., Fehr & Peers (transportation planning and engineering firm), Contra Costa Transportation Authority, other local agencies, articles, and published research, etc.) to develop recommendations for VMT assessment, thresholds of significance, and mitigation measures for the unincorporated County. Contra Costa County Transportation Analysis Guidelines (June 2020) June 2020, the Board of Supervisors adopted new Transportation Analysis Guidelines (“Guidelines”) for implementing SB 743, including Vehicle Miles Traveled (“VMT”) as the metric for evaluating transportation impacts of proposed projects under CEQA. Department of Conservation and Development (“DCD”) and Public Works Department (“PWD”) staff along with County Counsel and Fehr & Peers formed an interdepartmental working group (“working group”) for SB 743 implementation. The working group met biweekly to discuss development of policies, methodology, procedures, and implementation of VMT. The working group was also tasked with determining how the County will continue to use LOS as an evaluation tool for certain transportation facility operations. Estimating VMT The Guidelines provide screening criteria for projects that should be expected to cause a less-than-significant impact under CEQA and would not require further VMT analysis, absent substantial evidence indicating that a project would generate a potentially significant level of VMT. These types of “screenable” projects generally include: Projects generating fewer than 110 dial vehicle trips, or projects of 10,000 square feet or less of non-residential space, or 20 residential units or less. Residential, retail, office projects, or mixed-use projects proposed within ½ mile of an existing major transit stop or an existing stop along a high-quality transit corridor. Residential projects at 15% or below the baseline Countywide average VMT per capita, or employment projects at 15% or below the baseline Bay Area VMT per capita. Public facilities and government buildings. The Guidelines recommend two methods for calculating VMT: Inserting the proposed project into the CCTA Countywide Model. Using the CCTA model to determine both trip generation and trip lengths allows consistent analysis methodology; or, Utilizing existing average trip length data of similar Traffic Analysis Zones (“TAZ”) that contain similar mixes of land uses.  A traffic analysis zone (“TAZ”) is a special area delineated by state and/or local transportation officials for tabulating traffic-related data, especially commute data. A TAZ usually consists of one or more census blocks, block groups, or census tracts. The CCTA model uses TAZs to better understand trip behavior and estimate trip length using socio-economic data (e.g., number of automobiles per household, household income, and employment within these zones).  Contra Costa Transportation Authority (“CCTA”) February 2021, CCTA updated the Growth Management Program (“GMP”) Implementation Guide to include recommended methodology for compliance with the requirements of SB 743 and analysis of VMT for land use projects subject to CEQA. This guidance is intended to assist lead agencies in their CEQA VMT analysis consistent with new requirements of the CCTA GMP. The County’s Guidelines, which were adopted prior to CCTA adopting their updated GMP Implementation Guide, are consistent with the GMP Implementation Guide’s recommendations.  Recommendation(s)/Next Step(s): CONSIDER the report, provide COMMENT and DIRECT staff as appropriate.  Fiscal Impact (if any): None to the General Fund. Measure J funds staff time toward implementation of SB 743.  Attachments SB 743 ppt 1 Transportation, Water and Infrastructure Committee November 8, 2021 CONTRA COSTA COUNTY SENATE BILL 743 IMPLEMENTATION Transportation, Water and Infrastructure Committee Conservation and Development Department Monday, November 8, 2021 AGENDA •What is Senate Bill (“SB”) 743? •SB 743 Implementation •Contra Costa Transportation Authority (“CCTA”) •Contra Costa County (CEQA Lead Agency) •Questions/Discussion 3 SENATE BILL (“SB”) 743 LEGISLATIVE BACKGROUND 4 Assembly Bill (“AB”) 32 (Nunez, 2006) Senate Bill (“SB”) 375 (Steinberg, 2008) SB 743 (Steinberg, 2013) SB 32 (Pavley, 2016)Mandatory Statewide Implementation of SB 743 (July 2020) County Adopted Transportation Analysis Guidelines (June 2020) CCTA Growth Management Implementation Guide Update (February 2021) SB 743 IMPLEMENTATION •California Office of Planning and Research Technical Advisory on Evaluating Transportation Impacts (2018) •Technical recommendations regarding assessment of VMT, thresholds of significance, and mitigation measures. •Technical Advisory is a resource for local agencies and the public to use at their discretion. •Thresholds of Significance:•OPR recommendation: A proposed project exceeding a level of 15 percent below existing VMT per capita may indicate a significant transportation impact. •Projects would need to mitigate impacts to less-than-significant levels or prepare an Environmental Impact Report. •Why 15 percent? •Various legislative mandates and state policies establish quantitative greenhouse gas emissions reduction targets. •Consistent with SB 743’s direction to OPR to select a threshold that will help the State achieve its climate goals. 5 SB 743 IMPLEMENTATION (CONTRA COSTA COUNTY) •Contra Costa County Transportation Analysis Guidelines (June 2020) •Developed by County Department of Conservation and Development and Public Works Department with assistance from Fehr & Peers (Envision Contra Costa 2040 and CCTA VMT Guidelines) •Follows State Office of Planning and Research Technical Advisory on Evaluating Transportation Impacts in CEQA (2018) •Evaluating VMT •Is the project subject to CEQA? •Screening Criteria •CEQA Thresholds of Significance •Estimating VMT 6 CCTA GROWTH MANAGEMENT PROGRAM (“GMP”) IMPLEMENTATION GUIDE (2021) 7 •Guidance intended to assist lead agencies in their CEQA VMT analysis. •Compliance with the requirements of this document is mandatory as part of fulfillment of local jurisdictions’ requirements under the CCTA GMP. •Local jurisdictions may choose to apply methods and thresholds that are more stringent than those outlined in the GMP Guide and would still be in compliance with CCTA GMP requirements. •Lead agencies have the ultimate responsibility for determining the most appropriate way to comply with CEQA when conducting environmental review of their projects; nothing in this memorandum should be construed as legal advice nor should it take the place of consultation with the lead agency’s CEQA experts. (CCTA Implementation Guide, Appendix F (February 2021)) THANK YOU Questions/Discussion 8 TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE 6. Meeting Date:11/08/2021   Subject:RECEIVE Report on Adoption of the East Contra Costa Groundwater Sustainability Plan Submitted For: John Kopchik, Director, Conservation & Development Department  Department:Conservation & Development Referral No.: 6   Referral Name: Sustainable Groundwater Management Act  Presenter: Vicki Kretsinger, LSCE Contact: Ryan Hernandez (925)655-2919 Referral History: This report is in fulfillment of the TWIC referral to monitor compliance of the Sustainable Groundwater Management Act (SGMA). In 2014, a legislative package, referred to as the Sustainable Groundwater Management Act (SGMA), created a fundamental change in the governance of California’s groundwater. SGMA required the formation of groundwater sustainability agencies (GSAs) for over 140 groundwater basins, including the East Contra Costa (ECC) Subbasin. Signed into law by Governor Jerry Brown, and effective January 1, 2015, SGMA set forth a long-term, statewide framework to protect groundwater resources. Under the new law, the seven ECC GSAs, each charged with the development and implementation of a groundwater sustainability plan (GSP), were formed within the ECC Subbasin (Subbasin). The purpose and intent of the SGMA mandate is for groundwater to be managed by local public agencies (GSAs) to ensure a groundwater basin is operated within its sustainable yield through the development and implementation of a GSP. The GSAs, along with partners, worked collaboratively to prepare a single GSP for the ECC Subbasin in accordance with the codified principle that sustainable groundwater management is best achieved locally. The Subbasin boundary and GSA areas are shown in Exhibit “A”. The East Contra Costa Groundwater Subbasin is a medium priority basin, (Basin 5-22.19, San Joaquin Valley) and is located entirely within Contra Costa County. The seven GSAs listed below, and the Contra Costa Water District make up the “Working Group” and overly all portions of the ECC Subbasin.  City of Antioch City of Brentwood Byron Bethany Irrigation District Contra Costa County Diablo Water District Discovery Bay Community Services District East Contra Costa Irrigation District It is worth noting the original boundary of the Tracy Groundwater Subbasin included the jurisdiction of multiple cities and the counties of Contra Costa and San Joaquin. To streamline the development of the required GSP, the GSAs in Contra Costa and San Joaquin Counties, on September 6, 2018, applied to the State to divide the Tracy Subbasin along the border of Contra Costa and San Joaquin Counties. On February 11, 2019, the California Department of Water Resources (DWR) approved dividing the Tracy Subbasin into two subbasins (e.g., East Contra Costa Subbasin and the new Tracy Subbasin) thereby creating a separate groundwater basin entirely within Contra Costa County. Contra Costa County is a Groundwater Sustainability Agency (GSA) and overlies a portion of the East Contra Costa Groundwater Subbasin. The Working Group have prepared a final Groundwater Sustainability Plan dated October 15, 2021, attached Exhibit “B” to be considered for adoption by the Board of Supervisors; and if adopted, submitted to the DWR by January 31, 2022. Referral Update: Groundwater conditions in the ECC Subbasin are favorable and reflect stability over the past 30 years or more. Using various analogies, the Subbasin can be described as generally full through various water-year types, including drought, and is in good “health.” The favorable conditions are in part due to surface water availability that represents the largest source of supply for municipal and agricultural uses in the Subbasin. The sustainability goal for this GSP establishes the protection of all beneficial uses and users of groundwater in the ECC Subbasin. The GSAs represent and are responsible to the needs and values of all water users present in the Subbasin including urban and rural residents, farmers, various commercial industries, and environmental users all of which rely on groundwater to one degree or another. The GSAs have endeavored to reach out and engage these constituencies to ensure that this GSP reflects all concerns over water supply whether quality, quantity, or both. From residents that rely on a small capacity well providing drinking water in their homes, to small farmers that rely wholly on groundwater for their businesses and livelihoods, and to small water systems serving disadvantaged communities, this GSP recognizes that declining water levels and degradation of water quality as potentially having particularly harmful effects on health and welfare. The GSP also values the unique Delta environment and long history of agricultural activity for which sustainable management is vital to the character and economic diversity of the region. The GSAs have adopted sustainable management principles that include engagement of all interested parties and stakeholders; protection of potentially underrepresented communities; recognition and prioritization of environmental justice and groundwater dependent ecosystems; and continuation of cooperative water resources management to ensure that all activities needed to maintain sustainability are identified, funded, and implemented. Using the best available data and a robust water budget model, the ECC Subbasin is projected to Using the best available data and a robust water budget model, the ECC Subbasin is projected to be sustainable under various future scenarios including those that incorporate climate change and sea level rise. The attached ECC GSP dated October 15, 2021, refer to Exhibit B provides a comprehensive analyses on these findings. Additionally, the development of the ECC GSP was a collaborative effort among the ECC GSP Working Group (seven GSAs and CCWD), technical consultants, community members, and stakeholders. The Working Group conducted over 40 meetings, from 2018 to 2021. GSP documents are posted to a publicly accessible website. Working Group meeting notes, surveys, newspaper notices, and direct email outreach were used to keep the public informed of the GSP development and provide opportunities for public input. The Working Group members also provided regular updates through individual agency public meetings and websites. Notice of opportunities to provide input were announced on the Department of Conservation and Development’s (DCD) webpage, the Contra Costa County Water Agency webpage and also provided through DCDs social media. Supervisor Burgis’ weekly emailed newsletter was also used to inform the public. Additionally, three recorded public workshops, held between July 2020 and September 2021, were used to inform and engage beneficial users of groundwater in the ECC Subbasin and discuss each section of the GSP. There are three Municipal Advisory Council’s (Council) in the unincorporated County within the ECC groundwater basin, Bethel Island, Byron and Knightsen. Each Council meets regularly to advise the County Board of Supervisors on discretionary land use projects, among other things. The County GSA emailed the complete draft GSP to individual members of each Council and gave a presentation on the findings of the draft GSP on the following dates:  Knightsen Town Advisory Council-September 14, 2021 Byron Municipal Advisory Council-September 28, 2021 Bethel Island Municipal Advisory Council-October 12, 2021 Public comments received on the draft GSP have been reviewed by the Working Group and, where appropriate, changes are incorporated into the final GSP. To date, the Discovery Bay Community Services District and the Diablo Water District Boards have adopted the ECC GSP on October 20, 2021, and October 27, 2021, respectively. It’s anticipated that the remaining GSAs and CCWD will adopt the ECC GSP prior to the end of the calendar year. Later this year or early 2022, a new or revised Memorandum of Understanding (MOU) will be presented to the Board. The MOU will contain the framework for continued work with fellow local GSAs on mandatory annual reports, expanding the groundwater monitoring well network, and establishing funding requirements for preparation of the required five-year comprehensive review of the ECC GSP. Exhibit B - ECC GSP and Appendices SGMA Documents & Reports — East Contra Costa County Integrated Regional Water Management (eccc-irwm.org) Recommendation(s)/Next Step(s): 1) RECEIVE the report on the East Contra Costa Groundwater Sustainability Plan dated October 1) RECEIVE the report on the East Contra Costa Groundwater Sustainability Plan dated October 15, 2021, attached Exhibit “B”; and 2) CONSIDER recommending the Board of Supervisors, as the Groundwater Sustainability Agency for portions of the East Contra Costa Subbasin (DWR Basin 5-22.19), adopt the East Contra Costa Groundwater Sustainability Plan dated October 15, 2021, at a public hearing on December 7, 2021; and 3) AUTHORIZE the Director of Conservation and Development, or designee, to take such actions as may be reasonably necessary to submit the East Contra Costa Groundwater Sustainability Plan, dated October 15, 2021, to DWR by January 31, 2022. Fiscal Impact (if any): Costs to prepare the ECC GSP is divided evenly among the Working Group, also known as the parties to the agreement, except that the County may elect to satisfy some or all of its cost-share obligation through in-kind services performed by County staff, which will be funded by the Water Agency. Attachments Exhibit A - ECC Subbasin Map Exhibit B – ECC GSP & Appendices Exhibit C - ECC GSP Resolution ECC GSP Presentation Slides AlamedaCounty SolanoCounty SacramentoCounty ContraCostaCounty SanJoaquinCounty ContraCostaCounty ÄÅ44 ÄÅ160 ÄÅ44 ÄÅ44 BethelIsland Byron Knightsen ShermanIsland WebbTract BaconIsland VictoriaIslandByronTract HollandTract JerseyIsland MandevilleIsland UnionIsland BouldinIsland TwitchellIsland PalmTract BradfordIsland VeniceIsland OrwoodTract Veale Tract AndrusIsland WoodwardIsland ConeyIsland QuimbyIsland DeckerIsland WinterIsland Oakley City ofAntiochGSA City ofBrentwoodGSA Pittsburg BixlerTractSanJoaquinRiver Old RiverOld RiverMiddle River False River Dutch Slough Conne c t i o n S l o u g h Pi p e r S l o u g h T a y l o r S l o u g h Rock SloughSand Mound SloughHolland CutFisherman's CutIndian Slou g h Woodward CanalSheep SloughFranksTract BigBreak ShermanLake CliftonCourtForebay LosVaquerosReservoir Broad Slough Little FranksTract ContraLomaReservoir AntiochMunicipalReservoir MarshCreekReservoir Dredgers Cut Victoria CanalItalian SloughWest Cana l Grant Line Canal California AqueductDelta Mendota CanalMokelumne River Sacramento RiverDiabloWaterDistrictGSA Discovery BayCommunity Services District GSA ContraCostaCountyGSA East ContraCostaIrrigationDistrictGSA ByronBethanyIrrigation DistrictGSA Groundwater Sustainability Agencies in the East Contra Costa Subbasin (5-022.19) 0 3 61.5 MilesThis map or dataset was created by the Contra Costa County Department of Conservationand Development with data from the Contra Costa County GIS Program. Some base data, primarily City Limits, is derived from the CA State Board of Equalization'stax rate areas. While obligated to use this data the County assumes no responsibility forits accuracy. This map contains copyrighted information and may not be altered. It may be reproduced in its current state if the source is cited. Users of this map agree to read and accept the County of Contra Costa disclaimer of liability for geographic information.® Diablo Water District GSA Brentwood GSA Antioch GSA Byron-Bethany Irrigation District GSA East Contra Costa Irrigation District GSA Discovery Bay Community Services District GSA Water Providing District Irrigation District City Contra Costa County Contra Costa County GSA Map created 08/26/2019by Contra Costa County Department ofConservation and Development, GIS Group30 Muir Road, Martinez, CA 9455337:59:41.791N 122:07:03.756W East Contra Costa Subbasin City Limit October, 2021 EASTCONTRA COSTASUBBASIN East Contra Costa Subbasin Groundwater Sustainability Plan Prepared for ECC GSA Working Group EAST CONTRA COSTA SUBBASIN GROUNDWATER SUSTAINABILITY PLAN PREPARED FOR ECC GSA WORKING GROUP Debra Cannon Barbara Dalgish PREPARED BY October 2021 EAST CONTRA COSTA SUBBASIN GROUNDWATER SUSTAINABILITY PLAN OCTOBER 15, 2021 The East Contra Costa (ECC) Subbasin Working Group appreciates and acknowledges the funding of $538,000 from the California Department of Water Resources (DWR) funding under the Sustainable Groundwater Planning Grant Program (SGWP), authorized by the Water Quality, Supply, and Infrastructure Improvement Act of 2014 (Proposition 1) in 2017. The ECC Subbasin is using these funds for development of the ECC Subbasin Groundwater Sustainability Plan (GSP). The ECC Subbasin was also successful in securing $1,078,600 from the California Drought, Parks, Climate, Coastal Protection, and Outdoor Access for All Act of 2018 (Proposition 68). Tasks under this grant include extended outreach, expanding knowledge regarding data gaps within the groundwater monitoring system, and continuing GSP development. Additional funding for GSP development has come from direct contributions and in-kind services from the ECC Working Group. ECC Working Group City of Antioch GSA, Byron-Bethany Irrigation District GSA, City of Brentwood GSA, Contra Costa Water District, County of Contra Costa GSA, Diablo Water District GSA, Discovery Bay Community Services District GSA, and East Contra Costa County Irrigation District GSA comprise the ECC Subbasin Working Group. Luhdorff & Scalmanini Consulting Engineers and ERA Economics compose the LSCE Team for the ECC Subbasin Groundwater Sustainability Plan. Debbie Cannon PG, Senior Hydrogeologist Barbara Dalgish PG, Senior Hydrogeologist Tom Elson, Senior Principal Engineer Vicki Kretsinger Grabert, Senior Principal Hydrologist Charlie Jenkins PG, Project Geologist Lisa Lavagnino, Project Geologist Faithe Lovelace Carr, Project Hydrogeologist Jeevan Jayakody PG, Project Hydrogeologist Priyanka Swadi, Database Specialist Ken Utley PG, CEG, Senior Geologist Henry Ferdon MS, Associate Economist Duncan MacEwan PhD, Principal Economist Public outreach efforts and facilitation services were supported by Stantec through the DWR-funded Facilitation Support Services. Lisa Beutler, Executive Facilitator Megan Murray ENV SP, Water Resources Planner EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE i TABLE OF CONTENTS EXECUTIVE SUMMARY (CCR §354.4(A)) .............................................................................................. ES-1 1. INTRODUCTION .......................................................................................................................1-1 1.1. Background ................................................................................................................................ 1-1 1.1.1. Purpose of the Groundwater Sustainability Plan ............................................................... 1-1 1.1.2. Sustainability Goal .............................................................................................................. 1-1 1.1.3. Description of the East Contra Costa Subbasin .................................................................. 1-1 1.2. Agency Information ................................................................................................................... 1-2 1.2.1. GSAs in East Contra Costa Subbasin .................................................................................. 1-2 1.2.2. Agency Names and Mailing Addresses .............................................................................. 1-4 1.2.3. Agencies’ Organization, Management Structure, and Legal Authority of the GSAs and CCWD ................................................................................................................................. 1-5 1.2.4. Governance Structure ........................................................................................................ 1-7 1.3. Report Organization and Elements Guide ................................................................................. 1-8 1.4. References ................................................................................................................................. 1-9 2 PLAN AREA………………………………………………………………………………………………………………………………….2-1 2.1 Description of Plan Area ...................................................................................................................2-1 2.1.1 Summary of Jurisdictional Areas and Other Features (§354.8 a and b) .......................... 2-1 2.1.2 Density of Wells ............................................................................................................. 2-12 2.2 Water Resources Monitoring and Management Programs (10727G) (§354.8c, d, and e) ......... 2-19 2.2.1 CASGEM and Historical Groundwater Level Monitoring ............................................... 2-19 2.2.2 Department of Water Resources (DWR) and EWM ....................................................... 2-21 2.2.3 Groundwater Ambient Monitoring and Assessment Program (GAMA) ........................ 2-21 2.2.4 GeoTracker ..................................................................................................................... 2-21 2.2.5 California Division of Drinking Water (DDW) ................................................................. 2-21 2.2.6 U.S. Geological Survey (USGS) ....................................................................................... 2-21 2.2.7 Subsidence Monitoring .................................................................................................. 2-21 2.2.8 Climate Monitoring ........................................................................................................ 2-23 2.2.9 Incorporating Existing Monitoring Programs into the GSP ............................................ 2-23 2.2.10 Limits to Operational Flexibility ..................................................................................... 2-23 2.2.11 Conjunctive Use ............................................................................................................. 2-23 2.3 Land Use Elements or Topic Categories of Relevant General Plans (§354.8a and f) .................. 2-24 2.3.1 Current and Historical Land Use .................................................................................... 2-24 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE ii 2.3.2 Disadvantaged Area: DAC, SDAC and EDA ..................................................................... 2-28 2.3.3 Water Use Sector and Water Source Type .................................................................... 2-33 2.3.4 General Plans ................................................................................................................. 2-33 2.3.5 Water Management Plans ............................................................................................. 2-38 2.4 County Well Construction, Destruction and Permitting .............................................................. 2-40 2.4.1 Wellhead Protection and Well Permitting ..................................................................... 2-40 2.5 Additional Plan Elements (WCS 10727.4) ..................................................................................... 2-42 2.6 References ..................................................................................................................................... 2-43 3. Basin Setting…………………………………………………………………………………………………………………………….3-1 3.1 Overview .................................................................................................................................... 3-1 3.2 Hydrogeologic Conceptual Model ............................................................................................. 3-1 Regional Geological and Structural Setting ........................................................................ 3-1 Faults and Structural Features ........................................................................................... 3-7 Basin Boundaries ................................................................................................................ 3-7 Geologic Cross Sections and Depositional Facies Model ................................................. 3-10 Principal Aquifers and Aquitards ..................................................................................... 3-14 Soil Characteristics ........................................................................................................... 3-15 Groundwater Recharge and Discharge Areas .................................................................. 3-20 Imported Supplies ............................................................................................................ 3-26 Surface Water Bodies ....................................................................................................... 3-26 Hydrogeologic Conceptual Model Data Gaps and Uncertainty ....................................... 3-26 3.3 Groundwater Conditions ......................................................................................................... 3-28 Groundwater Levels ......................................................................................................... 3-28 Groundwater Elevation Contours .................................................................................... 3-36 Storage ............................................................................................................................. 3-41 Seawater Intrusion ........................................................................................................... 3-41 Groundwater Quality ....................................................................................................... 3-46 Groundwater Contamination Risk ................................................................................... 3-57 Land Subsidence............................................................................................................... 3-61 Interconnected Surface Water Systems .......................................................................... 3-65 Groundwater Dependent Ecosystems ............................................................................. 3-67 3.4 Summary…………………………………………………………………………………………………………………………….3-83 3.5 References………………………………………………………………………………………………………………………….3-85 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE iii HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY .............................................................. 4-1 4.1 Land Uses ................................................................................................................................... 4-1 4.2 Population Trends ...................................................................................................................... 4-5 4.3 Water Demands, Supplies and Utilization ................................................................................. 4-8 4.3.1 Historic and Current Water Supplies ................................................................................. 4-8 4.3.2 Projected Water Demands and Supplies ......................................................................... 4-18 4.3.3 Water Availability and Reliability ..................................................................................... 4-19 4.4 References ............................................................................................................................... 4-21 5. WATER BUDGET (§ 354.18) ...................................................................................................... 5-1 East Contra Costa Subbasin Hydrologic Base Period ................................................................. 5-1 Summary of Water Year 2015 Hydrologic Conditions ............................................................... 5-2 Projected 50-Year Hydrology (§354.18c3) ................................................................................. 5-2 Water Budget Framework ......................................................................................................... 5-3 Groundwater/Surface Water Flow Model ................................................................................. 5-5 Subbasin Water Budget Results (§354.18a, b, c and d) ........................................................... 5-14 Model Calibration and Uncertainty ......................................................................................... 5-49 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE iv Sensitivity Analysis (TBD) ......................................................................................................... 5-51 Sustainable Yield Scenario ....................................................................................................... 5-51 GSA Area Water Budget Results .............................................................................................. 5-56 Model Documentation ............................................................................................................ 5-66 References ............................................................................................................................... 5-66 6. MONITORING NETWORK AND DATA MANAGEMENT SYSTEM ...................................................... 6-1 6.1. Monitoring Network Objectives (CCR§354.34, §354.38) .......................................................... 6-1 6.2. Monitoring Networks ................................................................................................................ 6-2 6.2.1. Basin-Wide and Representative Monitoring Networks ................................................... 6-2 6.2.2. Groundwater Level Monitoring Network ........................................................................ 6-3 6.2.3. Groundwater Quality Monitoring Network ................................................................... 6-14 6.2.4. Seawater Intrusion Monitoring Network ....................................................................... 6-19 6.2.5. Land Subsidence Monitoring Network .......................................................................... 6-21 6.2.6. Interconnected Surface Water Monitoring Network .................................................... 6-23 6.3. Protocols for Data Collection and Monitoring (§ 352.2) ......................................................... 6-26 6.4. Data Gaps ................................................................................................................................. 6-26 6.4.1. Well Inventory Data Gap ................................................................................................ 6-27 6.5. Ongoing Monitoring Network Evaluation................................................................................ 6-28 6.6. Groundwater Data Management ............................................................................................ 6-28 6.7. Data Management System (§ 352.6) ....................................................................................... 6-28 6.8. Data Use and Disclosure .......................................................................................................... 6-29 6.9. Data Submittals ....................................................................................................................... 6-29 6.10. Reporting ................................................................................................................................. 6-29 6.11. References ............................................................................................................................... 6-29 7. SUSTAINABLE MANAGEMENT CRITERIA ........................................................................................ 7-1 7.1. Process to Establish Sustainable Management Criteria............................................................. 7-3 7.2. ECC Sustainability Goal .............................................................................................................. 7-4 7.2.1. Goal Description ................................................................................................................. 7-4 7.2.2. Historical, Existing and Potential Future Conditions of Undesirable Results..................... 7-5 7.2.3. Measures to be Implemented ............................................................................................ 7-5 7.2.4. Explanation of How the Sustainability Goal will be Achieved ........................................... 7-5 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE v 7.3. ECC Sustainability Indicators ...................................................................................................... 7-6 7.3.1. Chronic Lowering of Groundwater Levels .......................................................................... 7-7 7.3.2. Reduction in Groundwater Storage ................................................................................. 7-17 7.3.3. Seawater Intrusion ........................................................................................................... 7-18 7.3.4. Degraded Water Quality .................................................................................................. 7-23 7.3.5. Land Subsidence............................................................................................................... 7-28 7.3.6. Depletions of Interconnected Surface Waters ................................................................ 7-32 7.4. References ............................................................................................................................... 7-37 8. PROJECTS AND MANAGEMENT ACTIONS (§ 354.44) ..................................................................8-1 8.1 Projects ...................................................................................................................................... 8-4 Project Implementation .................................................................................................... 8-5 List of Projects ................................................................................................................... 8-5 Completed Projects ........................................................................................................... 8-8 Projects Under Construction ........................................................................................... 8-13 Planned Projects .............................................................................................................. 8-17 8.2 Management Actions ............................................................................................................... 8-21 Potential Management Actions ....................................................................................... 8-21 Other Water Conservation Actions ................................................................................. 8-31 8.3 References ............................................................................................................................... 8-33 9 PLAN IMPLEMENTATION ..........................................................................................................9-1 9.1 Estimate of GSP Implementation Costs ..................................................................................... 9-1 9.1.1 GSA Administration ............................................................................................................ 9-2 9.1.2 GSP Implementation .......................................................................................................... 9-3 9.1.3 GSP Updates ....................................................................................................................... 9-3 9.1.4 Monitoring and Data Management ................................................................................... 9-5 9.1.5 Contingency ....................................................................................................................... 9-6 9.2 GSA Implementation Costs ........................................................................................................ 9-7 9.2.1 Byron-Bethany Irrigation District GSA ............................................................................... 9-8 9.2.2 City of Antioch GSA ............................................................................................................ 9-8 9.2.3 City of Brentwood GSA ....................................................................................................... 9-9 9.2.4 Contra Costa Water District ............................................................................................... 9-9 9.2.5 County of Contra Costa GSA ............................................................................................ 9-10 9.2.6 Diablo Water District GSA ................................................................................................ 9-11 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE vi 9.2.7 Discovery Bay Community Services District GSA ............................................................. 9-11 9.2.8 East Contra Costa Irrigation District GSA ......................................................................... 9-12 9.3 GSP Funding and Financing ...................................................................................................... 9-13 9.4 Schedule for Implementation .................................................................................................. 9-14 9.5 Initial and Subsequent Annual Reporting ................................................................................ 9-17 9.6 Periodic (5-Year) Evaluation and Reporting ............................................................................. 9-19 9.6.1 Sustainability Evaluation (§356.4(a) - §356.4(d)) ............................................................. 9-19 9.6.2 Monitoring Network Description (§356.4(e)) .................................................................. 9-20 9.6.3 New Information (§356.4(f)) ............................................................................................ 9-20 9.6.4 GSA Actions ((§356.4(g) - §356.4(h)) ............................................................................... 9-20 9.6.5 Plan Amendments, Coordination, and Other Information (§356.4(i) - §356.4(k)) .......... 9-21 10. NOTICE AND COMMUNICATION (§ 354.10)…………………………………………………………………………10-1 10.1. Description of Beneficial Uses and Users of Groundwater in the Basin .............................. 10-1 Interest Groups ................................................................................................................ 10-1 ECC GSP Advisory Groups ................................................................................................ 10-3 10.2. List of Public Meetings Where the GSP was Discussed ........................................................ 10-3 Informational Public Meetings on ECC GSP ..................................................................... 10-3 Outreach Presentations to Community Groups .............................................................. 10-5 10.3. Comments on the GSP and a Summary of Responses ......................................................... 10-5 10.4. Decision-Making Process ..................................................................................................... 10-5 10.5. Opportunities for Public Engagement and How Public Input and Response was Used ...... 10-5 10.6. Encouraging Active Involvement ......................................................................................... 10-7 10.7. Informing the Public on GSP Implementation Progress ...................................................... 10-7 10.8. Interbasin Coordination ....................................................................................................... 10-7 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE vii LIST OF TABLES Table 2-1 Region Water Management Group Members and Primary Function ............................. 2-4 Table 2-2 Types of Wells ................................................................................................................ 2-19 Table 2-3 Land Use Summary ........................................................................................................ 2-24 Table 2-4 Area Summary of Disadvantaged Areas ........................................................................ 2-29 Table 2-5 Population Summary of Disadvantaged Areas .............................................................. 2-30 Table 2-6 Additional Plan Elements ............................................................................................... 2-42 Table 3-1 Estimates of Total Groundwater Storage (2018) ........................................................... 3-41 Table 3-2 Water Quality Concentrations for Key Constituents ..................................................... 3-55 Table 3-3 Land Surface Displacement Rates at PBO Sites ............................................................. 3-61 Table 3-4 Vegetation Species in the ECC Subbasin ........................................................................ 3-73 Table 4-1 Historic, Current and Projected Population…………………………………………………………………4-6 Table 4-2 Groundwater Extractions by Water Use Sector, Historical and Current, ECC Subbasin…………………………………………………………………………………………..…………………………4-9 Table 4-3 Historical and Current Metered Surface Water Supplies by Water Use Sector, ECC Subbasin…………………………………………………………………………………………………4-10 Table 4-4 Total Water Use by Source and Water Use Sector, ECC Subbasin……………………………….4-11 Table 4-5 Projected Water Demand and Supply (including Antioch and Brentwood areas outside the Subbasin)………………………………………………………………………………………………..4-12 Table 5-1. Water Budget Components ............................................................................................. 5-4 Table 5-2 Water Balance Subregions ............................................................................................. 5-11 Table 5-3. Water Budget Accounting Components Simulated Using Eccsim ................................. 5-15 Table 5-4. Simulated Land And Water Use Budget Components For Base Period, Wy 1997-2018 (Units In Acre-Feet per Year, Afy) .................................................................................. 5-18 Table 5-5. Simulated Root Zone Budget Components For Base Period, Wy 1997-2018 (Units In Acre-Feet per Year, Afy) ................................................................................................. 5-19 Table 5-6. Simulated Groundwater Budget Components For Base Period, Wy 1997-2018 (Units In Acre-Feet per Year, Afy) ............................................................................................. 5-21 Table 5-7. Simulated Groundwater Inflow Components For Base Period, Wy 1997-2018 (Units Are In Acre-Feet per Year, Afy) ...................................................................................... 5-23 Table 5-8. Simulated Groundwater Outflows For Base Period, Wy 1997-2018 (Units Are In Acre-Feet per Year, Afy)…. ............................................................................................. 5-25 Table 5-9. Simulated Groundwater Storage Component For Base Period, Wy 1997-2018 (Units Are In Acre-Feet per Year, Afy) ............................................................................ 5-27 Table 5-10. Water Year Types During The Base Period .................................................................... 5-29 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE viii Table 5-11. Simulated Agricultural And Urban Supply And Demand (Units In Acre-Feet per Year, Afy) .................................................................................. 5-30 Table 5-12. Average Simulated Groundwater Budget Components By Water Year Type (Units In Acre-Feet per Year, Afy) ................................................................................................. 5-32 Table 5-13. Groundwater Budget Components For Water Year 2015 (Afy)..................................... 5-34 Table 5-14. Root Zone Budget For Water Year 2015 ........................................................................ 5-34 Table 5-15. Land And Water Use Budget Components For Water Year 2015 .................................. 5-34 Table 5-16. Future Scenario Water Year Types For Repeated And Adjusted Hydrology ................. 5-36 Table 5-17. Simulated Average Future Land And Water Use Budget Components (Units In Acre-Feet per Year, Afy) .................................................................................. 5-45 Table 5-18. Simulated Average Root Zone Budget Components (Area In Acres, Flows In Afy) ...... 5-46 Table 5-19. Simulated Average Groundwater Budget Component Flows (Units In Acre-Feet per Year, Afy) ........................................................................................................................ 5-48 Table 5-20. Average Simulated Groundwater Budget Components Used To Develop The Sustainable Yield Of The Ecc Subbasin ........................................................................... 5-54 Table 5-21. Simulated Groundwater Budget Components For Gsas In The Ecc Subbasin For Base Period, Wy 1997-2018 (Units Are In Acre-Feet per Year, Afy) ...................................... 5-57 Table 5-22. Simulated Future Scenario Groundwater Budgets For Individual GSAs ........................ 5-59 Table 6-1 Sustainability Indicators and Applicable Representative Monitoring Network……….…….6-2 Table 6-2 GSA Groundwater Level Monitoring Network………………………………………………………………6-3 Table 6-3 Basin-wide and Representative Groundwater Level Monitoring Network…………………...6-4 Table 6-4 Groundwater Level Monitoring Well Density Considerations……………………………………..6-11 Table 6-5 ECC Subbasin Groundwater Level Monitoring Networks Density……………………………….6-12 Table 6-6 Proposed New Monitoring Wells to Fill Data Gaps……………………………………………………..6-14 Table 6-7 GSA Groundwater Quality Monitoring Network…………………………………………………………6-15 Table 6-8 Basin-Wide and Representative Groundwater Quality Monitoring Network………………6-16 Table 6-9 Basin-wide Interconnected Surface Water Monitoring Network………………………………..6-25 Table 7-1 Summary of Undesirable Results Applicable to the Plan Area……………….……….……………7-5 Table 7-2 Minimum Thresholds, Measurable Objectives, and Interim Milestones for Chronic Lowering of Groundwater Levels.…………………………………….………………………………………….7-10 Table 7-3 Constituents of Concern for Groundwater Quality Minimum Threshold.…….…………….7-25 Table 7-4 Minimum Thresholds, Measurable Objectives, and Interim Milestones for Degradation of Groundwater Quality…………………………………………………………………………7-28 Table 8-1 Summary of ECC GSP Projects & Management Actions..………………………………………………8-3 Table 8-2 Summary of ECC GSP Projects……………………………………...…………………………………………..…8-7 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE ix Table 8-3 City of Antioch Brackish Water Desalination Project Funding Sources…………….……….…8-17 Table 8-4 Summary of Potential Management Actions………………..………………………………………….…8-22 Table 8-5 Summary of Water Conservation Programs………………...………………………………………….…8-32 Table 9-1 ECC GSP Estimated Joint Implementation Costs…………………………………………………………..9-4 Table 9-2 ECC GSP Estimated Total of Individual GSA Implementation Costs………………………………9-7 Table 9-3 BBID GSA Implementation Costs………………………………………………………………………………….9-8 Table 9-4 City of Antioch GSA Implementation Costs…………………………………………………………………..9-9 Table 9-5 City of Brentwood GSA Implementation Costs……………………………………………………………..9-9 Table 9-6 CCWD Implementation Costs…………………………………………………………………………………….9-10 Table 9-7 County of Contra Costa GSA Implementation Costs……………………………………………………9-10 Table 9-8 DWD GSA Implementation Costs……………………………………………………………………………….9-11 Table 9-9 Discovery Bay Community Services District GSA Implementation Costs……………………..9-12 Table 9-10 ECCID GSA Implementation Costs………………………………………………………………………………9-12 Table 9-11 Potential Funding and Financing Sources for GSP Implementation…………………………….9-13 Table 10-1 List of Public Information Meetings and Outreach on the Draft ECC Subbasin……………10-4 Table 10-2 Public Comment Period for each GSP Section…………………………………………………………….10-6 LIST OF FIGURES Figure 1-1 East Contra Costa Subbasin, GSAs, and Adjacent Subbasins…………………………………………1-3 Figure 1-2 Management Structure, ECC Subbasin…………………………………………………………………………1-5 Figure 2-1 East Contra Costa Subbasin, GSAs, and Adjacent Subbasins ........................................... 2-2 Figure 2-2a Jurisdictional Boundary, Cities, Counties and Agencies with Water Management Responsibilities……………………………………………………………………………………………………………2-3 Figure 2-2b Jurisdictional Boundaries, Wastewater Agencies ............................................................ 2-7 Figure 2-3 Jurisdictional Boundaries, State, Federal Lands, and Special Districts ............................ 2-9 Figure 2-4 Water Related Infrastructure......................................................................................... 2-10 Figure 2-5a Legal Delta Boundary ..................................................................................................... 2-13 Figure 2-5b Legal Delta Boundary – Primary and Secondary Zones ................................................. 2-14 Figure 2-6a Domestic Well Density per Square Mile ........................................................................ 2-15 Figure 2-6b Production Well Density per Square Mile...................................................................... 2-16 Figure 2-6c Public Supply Well Density per Square Mile .................................................................. 2-17 Figure 2-6d Agricultural Well Density per Square Mile..................................................................... 2-18 Figure 2-7 ECC CASGEM Monitoring Network ................................................................................ 2-20 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE x Figure 2-8 Stream Gauges and Climate Stations ............................................................................. 2-22 Figure 2-9 Land Use-2014 & 2015 ................................................................................................... 2-25 Figure 2-10 Historical Land Use -1995 .............................................................................................. 2-26 Figure 2-11 Historical Land Use -1976 .............................................................................................. 2-27 Figure 2-12 Land Use Summary ........................................................................................................ 2-28 Figure 2-13a Summary of Disadvantaged Areas by Area .................................................................... 2-31 Figure 2-13b Summary of Disadvantaged Areas by Population .......................................................... 2-32 Figure 2-14 Land Use by Water Sector ............................................................................................. 2-34 Figure 2-15 Land Use by Water Source (2010) ................................................................................. 2-35 Figure 2-16 Relevant General Plans in ECC Subbasin........................................................................ 2-36 Figure 3-1a Surficial Geology and Faults ............................................................................................. 3-2 Figure 3-1b Surficial Geology Legend .................................................................................................. 3-3 Figure 3-1c Surficial Geology Legend………………………………………………………………….………………………….3-4 Figure 3-2 Topography and Surface Water Features ........................................................................ 3-6 Figure 3-3 Basin Boundary – Jurisdictional and Natural ................................................................... 3-8 Figure 3-4 Base of Freshwater .......................................................................................................... 3-9 Figure 3-5 Cross Section Location and Depositional Environment ................................................. 3-11 Figure 3-6a Geologic Cross Section 4-4’ ............................................................................................ 3-12 Figure 3-6b Geologic Cross Section C-C’ ........................................................................................... 3-13 Figure 3-7a Soil - Type ....................................................................................................................... 3-16 Figure 3-7b Soil - Texture .................................................................................................................. 3-17 Figure 3-7c Soil - Hydraulic Conductivity .......................................................................................... 3-18 Figure 3-7d Soil – Electrical Conductivity .......................................................................................... 3-19 Figure 3-8 Soil - Potential Recharge ................................................................................................ 3-21 Figure 3-9a Domestic Wells - Average Depth ................................................................................... 3-22 Figure 3-9b Public Supply Wells - Average Depth ............................................................................. 3-23 Figure 3-9c Agricultural Wells - Average Depth ................................................................................ 3-24 Figure 3-9d Domestic Well Depth…………………………………………………………………………………………………3-25 Figure 3-10 Surface Water Bodies and Monitoring Locations .......................................................... 3-27 Figure 3-11 Groundwater Level Monitoring Locations ..................................................................... 3-29 Figure 3-12a Selected Graphs of Groundwater Elevations- Shallow Zone ......................................... 3-30 Figure 3-12b Selected Graphs of Groundwater Elevations- Deep and Composite Zone .................... 3-31 Figure 3-13a Vertical Groundwater Gradients .................................................................................... 3-33 Figure 3-13b Vertical Groundwater Gradients ………………………………………………………………………………3-34 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xi Figure 3-13c Nested Monitoring Well Locations ................................................................................ 3-35 Figure 3-14a Groundwater Contours Spring 2012 - Shallow Zone ..................................................... 3-37 Figure 3-14b Groundwater Contours Spring 2018 - Shallow Zone ..................................................... 3-38 Figure 3-14c Groundwater Contours Spring 2012 - Deep Zone and Composite Wells ...................... 3-39 Figure 3-14d Groundwater Contours Spring 2018 - Deep Zone and Composite Wells ...................... 3-40 Figure 3-15 The Process of Saltwater Intrusion from an Aquifer ..................................................... 3-42 Figure 3-16a Partial Cross Section Location ........................................................................................ 3-43 Figure 3-16b Partial of Cross Section A-A’ .......................................................................................... 3-44 Figure 3-16c Partial Cross Section C-C’ ............................................................................................... 3-44 Figure 3-16d Chloride Isocontours for Deep Zone .............................................................................. 3-45 Figure 3-17a Average Total Dissolved Solids ...................................................................................... 3-47 Figure 3-17b Maximum Total Dissolved Solids ................................................................................... 3-48 Figure 3-18a Average Chloride ............................................................................................................ 3-49 Figure 3-18b Maximum Chloride ........................................................................................................ 3-50 Figure 3-19a Average Nitrate .............................................................................................................. 3-51 Figure 3-19b Maximum Nitrate ........................................................................................................... 3-52 Figure 3-20a Average Arsenic ............................................................................................................. 3-53 Figure 3-20b Maximum Arsenic .......................................................................................................... 3-54 Figure 3-21a Groundwater Contamination Sites and Plumes: Open Sites ......................................... 3-59 Figure 3-21b Groundwater Contamination Sites and Plumes: Closed Sites ....................................... 3-60 Figure 3-22 Land Subsidence Monitoring Locations ......................................................................... 3-62 Figure 3-23a Subsidence on Delta Islands .......................................................................................... 3-64 Figure 3-23b Cross-section of Subsidence and Drains on Delta Island ............................................... 3-65 Figure 3-24 Surface Water Features and Subsurface Drains ............................................................ 3-66 Figure 3-25a Depth to Shallow Groundwater – Spring 2018 .............................................................. 3-68 Figure 3-25b Interconnected Surface Water-Minimum Depth to Water Spring 2018 ....................... 3-69 Figure 3-26a Groundwater Dependent Ecosystems-Vegetation ........................................................ 3-70 Figure 3-26b Groundwater Dependent Ecosystems-Wetlands .......................................................... 3-71 Figure 3-27 Critical Habitat Map ....................................................................................................... 3-72 Figure 3-28a Normalized Difference Vegetation Index-1997 ............................................................. 3-76 Figure 3-28b Normalized Difference Vegetation Index-2004 ............................................................. 3-77 Figure 3-28c Normalized Difference Vegetation Index-2010 ............................................................. 3-78 Figure 3-28d Normalized Difference Vegetation Index-2015 ............................................................. 3-79 Figure 3-28e Normalized Difference Vegetation Index-2018 ............................................................. 3-80 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xii Figure 3-28f Normalized Difference Vegetation Index-Big Break ...................................................... 3-81 Figure 3-28g Normalized Difference Vegetation Index-Marsh Creek ................................................. 3-82 Figure 4-1 Change in Land Use 1984-2016……………………………………………………………………………………4-4 Figure 4-2 Historical, Current, and Projected Population………………………………………………………………4-7 Figure 5-1a Model Grid and Node Refinement……………………………………………………………………………….5-8 Figure 5-1b Model Grid and Node Refinement………………………………………………………….……………………5-9 Figure 5-1c Model Nodes for Simulated Surface Water Features……………………………….…………………5-10 Figure 5-2 Future Urban Footprint (2026) and Land Use (2016)…………………………………………………..5-13 Figure 5-3 Groundwater Budget for East Contra Costa Subbasin Historical Calibration Period (1997-2018)...……………………………………………………………………………………………………………5-22 Figure 5-4 Groundwater Budget Inflow Components East Contra Costa Subbasin Base Period (1997-2018)...……………………………………………………………………………………………………………5-24 Figure 5-5 Groundwater Budget Outflow Components East Contra Costa Subbasin Base Period (1997-2018).…………………………………………………………………………………………………..5-26 Figure 5-6 Groundwater Budget Storage Component East Contra Costa Subbasin Base Period (1997-2018)..…………………………………………………………………………………………………………….5-28 Figure 5-7 Average Simulated Change in Storage by Water Year Type…………………………………………5-31 Figure 5-8 Average Groundwater Budget Components During the Base Period (1997-2018) by Water Type……………………………………………………………………………………………………………5-33 Figure 5-9 Groundwater Budget for East Contra Costa Subbasin Future Land Use Scenario (1997-2068)………………………………………………………………………………………………………………5-38 Figure 5-10 Groundwater Budget for East Contra Subbasin Future Land Use and Climate Change Scenario (1997-2068)………………………………………………………………………5-39 Figure 5-11 Groundwater Budget for East Contra Subbasin Future Land Use and Sea Level Rise Scenario (1997-2068)…………………………………………………………………………………5-40 Figure 5-12 Groundwater Budget for East Contra Costa Subbasin Future Land Use, Climate Change, and Sea Level Rise Scenario (1997-2068)………………………………………………………5-41 Figure 5-13 Groundwater Budget for East Contra Costa Subbasin Future Land Use and Climate Change (Wet) Scenario (1997-2068)………………………………………………………………….……….5-42 Figure 5-14 Groundwater Budget for East Contra Costa Subbasin Future Land use and Climate Change (Dry) Scenario (1997-2068)…………………………………………………………….……………..5-43 Figure 5-15 Subset of Calibration Plots from ECCSim……………………………………………………………………5-50 Figure 5-16 Simulated vs Observed Groundwater Elevation by Layer……………………………………………5-51 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xiii Figure 5-17 Simulated Cumulative Change in Groundwater Storage for Sustainable Yield Development ……………………………………………………………………………………….………..…5-55 Figure 5-18 Average Water Budget Components During the Historical Calibration Period (1997-2018)……………………………………………………………………………..…………………….5-58 Figure 6-1a Basin-wide Groundwater Level Monitoring Network – Shallow Zone……………………….…6-5 Figure 6-1b Basin-wide Groundwater Level Monitoring Network – Deep Zone………………………………6-6 Figure 6-2 Representative Groundwater Level Monitoring Network…………………………………………..6-10 Figure 6-3 Data Gap – Shallow Zone Groundwater Level Monitoring Network……………………………6-13 Figure 6-4 Basin-wide Groundwater Quality Monitoring Network………………………………………………6-18 Figure 6-5 Representative Groundwater Quality Monitoring Network………………………………….……6-20 Figure 6-6 Land Subsidence Monitoring Network……………………………………………………………………….6-22 Figure 6-7 Interconnected Surface Water Monitoring Network………………………………………………….6-24 Figure 7-1 Relationship between Sustainability Indicators, Minimum Thresholds, and Undesirable Results….…………………………………………………………………………………………………7-2 Figure 7-2 Sustainability Management Criteria Example-Groundwater Levels………………………………7-3 Figure 7-3 Top of Well Perforations for Domestic Wells by Section…………………………..……………….7-12 Figure 7-4 Measurable Objectives and Minimum Thresholds – TODB Production Wells……….……7-16 Figure 8-1 ECC GSP Project Locations……………………………………………………………………………………………8-6 Figure 9-1 General Schedule of 20-year ECC GSP Plan Implementation……………………………………….9-15 Figure 9-2 ECC Subbasin Estimated Capital Outlay for Projects……………………………………………………9-16 Figure 9-3 ECC Subbasin Estimated Annual Costs for Project O&M and GSA Implementation…….9-17 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xiv LIST OF APPENDICIES Appendix 1a Definitions and Key Terms (CWC 10721 and 23 CCR 351) Appendix 1b Amended and Restated Memorandum of Understanding, Development of a Groundwater Sustainability Plan for the East Contra Costa Subbasin Appendix 3a Investigation of Ground-water Resources in East Contra Costa Area, 1999 Appendix 3b An Evaluation of Geological Conditions, East Contra Costa County, 2016 Appendix 3c Well Construction Table Appendix 3d Groundwater Level Hydrographs Appendix 3e Historical Groundwater Elevation Contour Maps Appendix 3f Groundwater Quality Table Appendix 3g Groundwater Quality Graphs (TDS, EC, Cl, NO3, As) Appendix 3h Groundwater Contamination Sites Appendix 3i ECC Subbasin Oil and Gas Wells and Fields Appendix 4a Individual Surface Water Diversions: Point of Delivery Totals by Tract/Model Subregion and by Calendar Year Appendix 5a Model Documentation Appendix 6a Monitoring Protocols Appendix 7a Representative Monitoring Sites Minimum Threshold, Measurable Objectives for Chronic Lowering of Groundwater Levels Appendix 7b Comparison of Domestic Wells and Depth to Minimum Threshold Appendix 9a East Contra Costa Groundwater Sustainability Plan Implementation Budget Appendix 10a Summary List of Public Meetings and Outreach Appendix 10b Summary of Public Comments on the Draft ECC GSP and Responses Appendix 10c ECC Subbasin Communications Plan EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xv LIST OF ACRONYMS & ABBREVIATIONS AB Assembly Bill AC Advisory Councils ACS US Census American Community Survey AF Acre Feet AFY Acre feet per year AMI Automatic Meter Infrastructure AMR Automated Meter Reading AMSL above mean sea level AN Above Normal ASR Aquifer Storage & Recovery AWMP Agricultural Water Management Plan BAC Bacon Island at Old River B&C Brown & Caldwell BBID Byron Bethany Irrigation District BBM Basin Boundary Modification bgs Below Ground Surface BIMID Bethel Island Municipal Improvement District bm bench mark BMP Best Management Practices BN Below Normal BPs Best Water Use Practices C Critical CA California Caltrans State Department of Transportation CASGEM California Statewide Groundwater Elevation CCC Contra Costa County CCCDCD Contra Costa County Department of Conservation and Development CCCEHD Contra Costa County Environmental Health Division CCCGP Contra Costa County General Plan CCHSHMP Contra Costa Health Services Hazardous Materials Programs CCR California Code of Regulations CCWD Contra Costa Water District CEC Constituent of Emerging Concern CEQA California Environmental Quality Act CESA California Endangered Species Act Cfs Cubic Feet per Second EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xvi CGMA Cooperative Monitoring/Adaptive Groundwater Management Agreement CGPS Continuous Global Positioning System CIMIS California Irrigation Management Information System COA Cooperated Use Agreement CoAGP City of Antioch General Plan COB or Brentwood City of Brentwood CoBGP City of Brentwood General Plan CoOGP City of Oakley General Plan COBWTP City of Brentwood Water Treatment Plant CPTs Cone Penetrating Testing CSD Community Services District CVHM Central Valley Hydrologic Model CVP Central Valley Project CVPIA Central Valley Project Improvement Act CVRWQCB or Regional Board Central Valley Regional Water Quality Control Board CWC California Water Code D Dry DA Disadvantaged Area DAC Disadvantaged Community DBCSD Discovery Bay Community Service District days/yr days per year DD Delta Diablo DDW California Division of Drinking Water DFW Department of Fish and Wildlife DMS Data Management System DNPG De Novo Water District DO dissolved oxygen DOD Department of Defense DPC Delta Protection Commission DQO Data Quality Objectives ds/m decimeters per meter DTW Depth to water DWD Diablo Water District DWR Department of Water Resources DWSAP Drinking Water Source Assessment and Protection DZ Deep Zone EBMUD East Bay Municipal Utilities District EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xvii EC Electrical Conductivity ECC or Subbasin East Contra Costa Subbasin ECCID East Contra Costa Irrigation District ECCSims East Contra Costa Groundwater Surface Water Simulation Model ECCWMA East Contra Costa Water Management Association EDA Economically Distressed Area EIR Environmental Impact Report (under CEQA) EIS Environmental Impact Study (under NEPA) EISIP Expanded irrigation System Improvement Program EPA U.S. Environmental Protection Agency ESA Endangered Species Act eWRIMS Electric Water Rights Information Management System ET (or ETo) evapotranspiration EWM Water Data Library EWMP Efficient Water Management Practices FMMP California Department of Conservation, Division of Land Resource Protection, Farmland Mapping and Monitoring Program FONSI Finding of no significant impact ft feet or foot ft/day feet per day ft/yr feet per year ft bgs feet below ground surface ft msl feet above mean sea level FSS Facilitation Support Services FTE Fulltime equivalent GAMA Groundwater Ambient Monitoring and Assessment GDE Groundwater Dependent Ecosystem GDEi Groundwater Dependent Ecosystem indicators GIS geographic information systems GMP Groundwater Management Plan gpd/ft gallons per day per foot gpm gallons per minute GPS Global Positioning System GQMP Groundwater Quality Management Plant GQTM Groundwater Quality Trend Monitoring Plan GSP or Plan Groundwater Sustainability Plan GSA Groundwater Sustainability Agency EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xviii GSFLOW Groundwater and Surface-water Flow Model GSI GSI Water Solutions, Inc. GW Groundwater GWE Groundwater Elevation GWMP Groundwater Management Program HCM Hydrogeologic Conceptual Model ILRP Irrigated Lands Regulatory Program IMs Interim Milestones InSAR Interferometric Synthetic-Aperture Radar IRWM Integrated Regional Water Management IRWMP Integrated Regional Water Management Plan ISD Ironhouse Sanitary District IWFM Integrated Water Flow Model JPA Joint Powers Authority KDSA Kenneth D. Schmidt & Associates LID Low Impact Development LAO Legislative Analyst’s Office LSA LSA Associates LSCE Luhdorff & Scalmanini Consulting Engineers LU Land Use LUST Leaky Underground Storage Tank MAF Million Acre-Feet MCL Maximum Containment Level MGD Million gallons per day µg/L microgram per liter mg/L milligrams per liter MHI Median Household Income MMP Monitoring and Mitigation Program MNM Monitoring Network Module MO Measurable Objectives MOA Memorandum of Agreement Model Groundwater Model MODFLOW Modular Finite-difference Flow Model MOU Memorandum of Understanding MRMP Mitigation Monitoring and Reporting Program msl Mean seal level MT Minimum Thresholds EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xix MTBE methyl tertiary-butyl ether MW monitoring well MWD Municipal Water District of South California MWR Master Water Report my million years mya million years ago mybp million years before present N Nitrogen NA Not Applicable NAHC Native American Heritage Commission NAIP National Agricultural Imagery Program NASL Naval Air Station Lemoore NDVI Normalized Derived Vegetation Index NAVD88 North American Vertical Datum of 1988 NCCAG Natural Communities Commonly Associated with Groundwater NEPA National Environmental Policy Act NHD National Hydrography Dataset NHP Natural Hydrography Database NMFS National Marine Fisheries Service NOI Notice of Intent NPDES Natural Pollution Discharge Elimination System NRCS Natural Resources Conservation Service NWIC Sonoma Northwest Information Center NWIS National Water Information System °C degrees Celsius °F degrees Fahrenheit O&M operations and maintenance ORP Oxidation Reduction OS Open Space OSWCR DWR Online System for Well Completion Reports PBO Plate Boundary Observatory pH potential of hydrogen PLSS Public Land Survey System PMAs Projects and Management Actions ppm parts per million ppt parts per trillion PUC Public Utilities Commission EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xx PWIS CA Water Boards Public Water Information System PWS Public Water System QA/QC Quality assurance/quality control RBWTP Randall Bold Water Treatment Plant RC Resource conservation RD Reclamation District RMP Representative Monitoring Point RMS Representative Monitoring Sites RP Reference Point RPE Reference Point Elevation RW recycled water RWQCB Regional Water Quality Control Board RWSA Raw Water Service Area SAGBI Soil Agricultural Groundwater Banking Index SB Senate Bill SCADA Supervisory Control and Data Acquisition SDAC Severely Disadvantaged Communities SRF State Water Resources Board Revolving Fund SGMA Sustainable Groundwater Management Act SJR San Joaquin River SMC Sustainable Management Criteria SMCL Secondary Maximum Containment Level SNL State Notification Level SNMP Salt and Nutrient Management Plan SOI Sphere of Influence SPI Standardized Precipitation Index SRF State Water Resources Control Board Revolving Fund SSURGO Soil Survey Geographic Database SWP State Water Project SWQCB State Water Quality Control Board SWRCB California State Water Resources Control Board SZ Shallow Zone TDS Total Dissolved Solids TMDLs Total Maximum Daily Load TNC The Nature Conservancy TODB Town of Discovery Bay Community Services District UAVSAR Uninhabited Aerial Vehicle Synthetic Aperture Radar EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TABLE OF CONTENTS LSCE xxi ULL Urban Limit Line Umhos/cm micromhos per centimeter UNAVCO University NAVSTAR Consortium UPRR Union Pacific Railroad USACE United States Army Corps of Engineers USFWS US Fish and Wildlife Services USGS United States Geologic Survey USBR United States Bureau of Reclamation USDA United States Department of Agriculture USFWS United States Fish and Wildlife Service UST Underground Storage Tanks UWMP Urban Water Management Plan Valley San Joaquin Valley VOC volatile organic chemical W Wet WCR Well Completion Report WDL Water Data Library WRAC Water Resources Advisory Committee WTP Water Treatment Plant WWTF Wastewater Treatment Facilities WWTP Wastewater Treatment Plant WY Water Year EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-1 EXECUTIVE SUMMARY (CCR §354.4(A)) In 2014, a legislative package, referred to as the Sustainable Groundwater Management Act (SGMA), created a fundamental change in the governance of California’s groundwater. SGMA required the formation of groundwater sustainability agencies (GSAs) for over 140 groundwater basins, including the East Contra Costa (ECC) Subbasin. Signed into law by Governor Jerry Brown, and effective January 1, 2015, SGMA set forth a long-term, statewide framework to protect groundwater resources. Under the new law, seven GSAs, each charged with the development and implementation of a groundwater sustainability plan (GSP), were formed within the ECC Subbasin (Subbasin). The purpose of a GSP is to sustainably manage groundwater and avoid undesirable results within and beyond the 50-year planning and implementation horizon. The GSAs along with partners, worked collaboratively to prepare a single GSP for the Subbasin in accordance with the codified principle that sustainable groundwater management is best achieved locally 1. The Subbasin boundary and GSA areas are shown in Figure ES-1. CONSIDERATION OF ALL BENEFICIAL USES AND USERS (WC §10723.2) Beneficial uses and users of water are established in the state constitution and codified in the state Code of Regulations. The State Water Board, which is charged with protection of all water resources, designates or establishes beneficial uses throughout the state. In the ECC Subbasin, which lies within the San Joaquin River Basin, groundwater is considered suitable for municipal and domestic water supply, agricultural supply, and industrial uses. The sustainability goal for this GSP establishes the protection of all beneficial uses and users of groundwater in the ECC Subbasin. The GSAs are comprised of two cities (Antioch and Brentwood), two special districts serving agricultural water supply (Byron Bethany Irrigation District and East Contra Costa Irrigation District), a special district and community services district providing municipal supply (Diablo Water District and Town of Discovery Bay), and Contra Costa County, which represents unincorporated areas not covered by other districts or cities. Along with Contra Costa Water District, which provides water to various municipal users in the region, these agencies represent and are responsible to the needs and values of all water users present in the Subbasin including urban and rural residents, farmers, various commercial industries, and environmental users all of which rely on groundwater to one degree or another. The GSAs have endeavored to reach out and engage these constituencies to ensure that this GSP reflects all concerns over water supply whether quality, quantity, or both. From residents that rely on a small capacity well providing drinking water in their homes, to small farmers that rely wholly on groundwater for their businesses and livelihoods, and to small water systems serving disadvantaged communities, this GSP recognizes that declining water levels and degradation of water quality as potentially having particularly harmful effects on health and welfare. It also values the unique Delta environment and long history of agricultural activity for which sustainable management is vital to the character and economic diversity of the region. The GSAs have adopted sustainable management principles that include engagement of all interested parties and stakeholders; protection of potentially underrepresented communities; recognition and prioritization of environmental justice and groundwater dependent ecosystems; and continuation of cooperative water resources management to ensure that all activities needed to maintain sustainability are identified, funded, and implemented. 1 California Water Code, Division 1, Section 113. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-2 Figure ES-1 East Contra Costa Subbasin Groundwater Sustainability Agencies EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-3 KEY FACTORS FOR THE ECC SUBBASIN GSP Through preparation of this GSP, key factors governed the approach and planning to meet the requirements of new SGMA regulations to ensure sustainability of groundwater resources in the plan area (see Figure ES-1). Some of these factors are listed below. ECC Subbasin Priority Ranking Many groundwater basins and subbasins in the state have experienced significant adverse effects attributed to overpumping; that is, pumping that exceeds groundwater replenishment. Such basins were assigned Critically Overdrafted and High priority rankings. The ECC Subbasin shows no signs of over pumping and was assigned a Medium priority ranking and is required to submit a GSP in January 2022. Although the ECC Subbasin has not been overdrafted, its ranking was based on the importance that groundwater serves as a source of supply for varied uses including domestic, agricultural, and environmental. Domestic users include individual residences, small water systems, and municipalities. In addition, there are many disadvantaged communities 2 that rely on groundwater as a sole source of supply. East Contra Costa also has a long history of agriculture dating back over 100 years. Sustainable Conditions in the ECC Subbasin Groundwater conditions in the ECC Subbasin are favorable and reflect stability over the past 30 years or more. Using various analogies, the Subbasin can be described as generally full through various water-year types, including drought, and is in good “health.” The favorable conditions are in part due to surface water availability that represents the largest source of supply for municipal and agricultural uses in the Subbasin. Outlook for Future Sustainability Using the best available data and a robust water budget model, the ECC Subbasin is projected to be sustainable under various future scenarios including those that incorporate climate change and sea level rise. Local Management of the ECC Subbasin On March 28, 2019, the state approved a subdivision of the Tracy Subbasin that separated the East Contra Costa portion (now called the ECC Subbasin) from the San Joaquin County portion (retained the Tracy Subbasin name), thereby providing more local control of groundwater resources. In addition, seven GSAs were formed by local public agencies to ensure that their diverse constituents are represented in this GSP. If needed, each GSA has authorities to enact policies to protect groundwater resources based on conditions within their respective jurisdictions. This provides stakeholders with more focused engagement through a local GSA. 2 Disadvantaged communities refer to the areas which most suffer from a combination of economic, health, and environmental burdens. The state identifies these areas by collecting and analyzing information from communities all over the state. https://www.cpuc.ca.gov/industries-and-topics/electrical-energy/infrastructure/disadvantaged-communities EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-4 Non-Applicability to De Minimis Extractors SGMA is intended to address existing and potential adverse effects typically attributed to the largest groundwater uses and users. Policies and programs aimed at achieving and maintaining sustainability may include pumping restrictions, fees, and reporting requirements. Such actions, which would be enacted locally by GSAs, do not apply to de minimis extractors. Under SGMA, a de minimis extractor is defined as a person who extracts two acre-feet or less per year of groundwater for domestic use. Thus, typical residential well owners are shielded from practically all potential management actions described in this GSP. Further, the GSP sustainability goal (Section 7) is intended to protect such users from adverse effects of sustainable management undertaken by the GSAs. Impacts to Individual Wells The GSP is concerned with protecting groundwater resources for future generations and maintaining sustainability as required under SGMA legislation. The GSP identifies baseline groundwater levels and water quality that protect all classes of beneficial users. The GSP does not mitigate conditions that were present prior to January 1, 2015 (Water Code 10727.2(b)(4)) such operational problems related to well features (e.g., depth, perforation interval, pump setting). Water Quality Groundwater contains numerous naturally occurring minerals that vary throughout the ECC Subbasin. While groundwater quality is generally favorable with respect to primary drinking water quality constituents, some areas have elevated total dissolved minerals, hardness, and some secondary constituents which may affect domestic and agricultural uses. The GSP is intended to avoid degradation of water quality as a result of implementing sustainable management policies, projects or actions; for example, projects that affect pumping patterns resulting in movement and mixing of groundwater sources would be evaluated to ensure that no adverse effects occur to any users. The GSP does not mitigate groundwater quality in the Subbasin that is naturally occurring during the historical baseline. Impacts of Drought Temporary imbalances between extraction and replenishment due to drought are not considered an undesirable result as long as groundwater conditions recover in subsequent normal to wet years. Thus, a drop in groundwater levels may occur in very dry years, which may produce a short-term impact on wells. GSP CONTENTS The GSP provides information demonstrating that the past and present actions of the ECC GSAs have created a sustainably managed groundwater basin. The GSP outlines planned management oversight and activities that will result in continued sustainability of the groundwater resources in east Contra Costa. This Executive Summary and the companion GSP are organized as follows: • Executive Summary • Section 1 Introduction • Section 2 Plan Area • Section 3 Basin Setting • Section 4 Historical, Current, and Projected Water Supply EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-5 • Section 5 Water Budget • Section 6 Monitoring Network and Data Management System • Section 7 Sustainable Management Criteria • Section 8 Project and Management Actions • Section 9 Plan Implementation • Section 10 Notice and Communication An overview of each section of the ECC Subbasin GSP is presented below. Section 1 Introduction The ECC Subbasin, also referred to as San Joaquin Valley-East Contra Costa Subbasin (5-022.19), is a Medium priority groundwater basin based on the Groundwater Basin Prioritization by the State Department of Water Resources (DWR). Under SGMA, Medium priority subbasins must submit an adopted GSP by January 31, 2022. Management of the ECC Subbasin through the GSP will be based on achieving and maintaining groundwater sustainability over a 50-year planning and implementation horizon. SGMA authorizes a “local public agency that has water supply, water management, or land use responsibilities within a groundwater subbasin or basin to elect to become a GSA and to develop, adopt, and implement a GSP (Water Code § 10721(n).)” The following agencies formed GSAs and coordinated preparation of this GSP. Figure ES-1 shows the service area for each GSA. • Byron Bethany Irrigation District (BBID) GSA • City of Antioch GSA • City of Brentwood GSA • Contra Costa County (CCC) GSA • Diablo Water District (DWD) GSA • Discovery Bay Community Services District (DBCSD 3) GSA • East Contra Costa Irrigation District (ECCID) GSA Contra Costa Water District (CCWD), while not a GSA, is a partner in the development of this jointly prepared GSP. CCWD provides surface water to various entities within its service area. Because surface water plays a part in future water resources management for the Subbasin, CCWD is an equal partner in the development of the ECC Subbasin GSP. On May 9, 2017, the seven GSAs and CCWD entered into a Memorandum of Understanding (MOU). Under this MOU the agencies share costs and management of the development and implementation of the GSP. 3 Also referred to as Town of Discovery Bay (TODB). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-6 Section 2 Plan Area The ECC Subbasin covers a 168-square mile area (107,596 acres) in the eastern portion of Contra Costa County (Figure ES-1). The Subbasin includes the communities of Antioch, Bethel Island, Byron, Brentwood, the Town of Discovery Bay (TODB), Knightsen, and Oakley and two agricultural districts (Byron Bethany Irrigation District and East Contra Costa Irrigation District). The Subbasin is located on the southwestern part of the Sacramento-San Joaquin Delta, which is the largest estuary on the West Coast and provides critical habitat to fish and wildlife species. The 2015 land use in the Subbasin is mainly agricultural (41 percent), followed by urban (about 23 percent), then by water and native vegetation (both about 14 percent). As quantified in Section 4, the Subbasin has three main water supply sources: surface water, groundwater, and recycled water. Surface water provides, on average, about 80 percent of the aggregate demand for all use sectors in the Subbasin. This percentage is projected to remain stable at 80 to 85 percent through at least 2050 (see Section 4, Table 4-5). Section 3 Basin Setting The ECC Subbasin setting is described through a hydrogeologic conceptual model depicting the physical features of the aquifer system and groundwater conditions. Hydrogeologic Conceptual Model • ECC Subbasin is bounded on the north, east, and south by the Contra Costa County line, which is contiguous with the San Joaquin River (north) and Old River (east). In the west, the Subbasin is bounded by marine sediments of the Coast Range. • Topography and geological formations gently slope to the northwest. The upper 400 feet of sediments are comprised of alluvial deposits with discontinuous clay layers interspersed with more permeable coarse-grained units. • The ECC Subbasin aquifer system is divided into the upper unconfined Shallow Zone (to about 150 feet below ground surface) and a lower semi-confined to confined Deep Zone (the Corcoran Clay is not present in the Subbasin). Most water wells are constructed within the upper 400 feet of the aquifer system. • Groundwater conditions throughout the Subbasin are monitored through water level measurements and water quality testing. Water level data indicate that groundwater storage is largely stable and fluctuate with water-year type (wet, normal, dry). Sustainability Indicators DWR is charged with determining the adequacy of GSPs in meeting SGMA’s requirements. Generally, to achieve sustainability, the amount of groundwater extracted must be less than or equal to the amount of groundwater replenishment. Temporary imbalances between extraction and replenishment due to drought are not considered an undesirable result as long as groundwater conditions recover in subsequent normal to wet years. In addition, the GSP regulations 4 list six sustainability indicators that must be addressed in GSPs. 4 California Water Code § 354.26 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-7 Following are the ECC findings for each of the sustainability indicators. • Groundwater Elevations- Groundwater levels in the ECC Subbasin are stable indicating that the Subbasin has been managed within its sustainable yield 5. This is partially due to surface water availability for agricultural and urban uses. • Change in Groundwater Storage - As determined through the water budget analysis in Section 5, the cumulative change in groundwater storage was unchanged between 1997 and 2018 despite three drought periods (2001-2002, 2007-2009, 2012-2016). • Seawater Intrusion - The ECC Subbasin is situated in the San Francisco Bay/Sacramento-San Joaquin Delta. This GSP recognizes the potential for interactions between saline baywater and shallow groundwater. While the baywater is fresh, adverse intrusion may occur if saline water infiltrates the Delta and intrudes into shallow groundwater. This potential mechanism may be triggered or exacerbated by sea level rise and/or shifts in groundwater flow directions and gradients caused by future pumping patterns. There is no direct connection between ocean seawater and groundwater in the Subbasin. • Groundwater Quality - Groundwater quality is generally favorable with respect to primary drinking water quality constituents. Naturally elevated mineral content may pose localized restrictions for domestic (e.g., hardness) and agricultural (crop sensitivity) uses. Key monitoring constituents are total dissolved solids, chloride, hardness, nitrate, and boron. With the exception of nitrate, these constituents are naturally occurring in the ECC Subbasin. • Land Subsidence - There is no historical evidence of inelastic land subsidence due to groundwater withdrawal in the ECC Subbasin. • Depletions of Interconnected Surface Water – This indicator is of concern where shallow groundwater and surface water are hydraulically connected. Marsh Creek, the San Joaquin River, and Old River are considered interconnected surface water bodies in the ECC Subbasin. Impacts to these features due to groundwater pumping will be managed through this GSP through monitoring of shallow wells and stream gage stations. 5 “Sustainable yield” means the maximum quantity of water, calculated over a base period representative of long-term conditions in the basin and including any temporary surplus, that can be withdrawn annually from a groundwater supply without causing an undesirable result. Cited from: Section 10733.2, Water Code EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-8 Section 4 Historical, Current, and Projected Water Supply This section describes the ECC Subbasin land uses, population, and metered historical, current and projected water supplies. Water supply amounts were provided by the GSAs and CCWD. When historical or projected water supply were not provided, land uses and population data were used to estimate these data. This information is integrated into the Subbasin surface water/groundwater model (GSP Section 5). Section 5 Water Budget In accordance with technical guidance documents provided by DWR, water budget scenarios were evaluated using a groundwater flow model that quantified historical, current, and projected groundwater budget conditions. The development of the ECC Groundwater-Surface Water Simulation Model (ECCSim) was a refinement of two other validated and widely used modeling platforms, IWFM and C2VSim-FG Beta26. These were selected as the modeling platform due to the versatility in simulating crop-water demands in the predominantly agricultural setting of the Subbasin, groundwater surface-water interaction, the existing hydrologic inputs existing in the model for the time period through the end of water year 2015, and the ability to customize the existing C2VSim-FG Beta2 model to be more representative of local conditions in the area of the ECC Subbasin. Use of publicly available modeling platforms is a guiding principle under DWR Best Management Practices 7 and facilitates independent assessment of modeling results. Based on the modeling results, the ECC Subbasin is historically, currently, and projected to be sustainable. Figure ES-2 shows a breakdown in water budget components for the model base period of 1997 to 2018. The modeling results indicate that the cumulative change in groundwater storage fluctuated while cumulative storage was essentially unchanged at the end of the base period despite three state-wide drought periods (2001-2002, 2007-2009, 2012-2016). Over the base period, total pumping in the Subbasin ranged from 32,500 to 58,250 AFY and averaged 46,455 AFY. 6 The development of the East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) involved starting with and evaluating the U.S. Geological Survey’s Central Valley Hydrologic Model (CVHM) and the beta version (released 5/1/2018) of DWR’s fine-grid version of the California Central Valley Groundwater-Surface Water Flow Model (C2VSim- FG Beta2). C2VSim-FG Beta2 utilizes the most current version of the Integrated Water Flow Model (IWFM) code available at the time of the ECCSim development. 7 23 CCR §352.4(f) EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-9 Figure ES-2 Groundwater Budget for East Contra Costa Subbasin Historical Calibration Period (1997-2018) Various future scenarios were evaluated using the ECC Subbasin groundwater flow model including sustainable yield. The projected sustainable yield is the amount of pumping that can occur while avoiding undesirable results for the six sustainability indicators. The sustainable yield for the ECC Subbasin is estimated at approximately 72,000 AFY, or about 55 percent greater pumping than the historical average. At higher levels of pumping, the modeling indicates the potential to increase streamflow depletion and inter-basin flow beyond historical baselines. Like the base period scenario, a chronic decline in groundwater storage was not a factor in the sustainable yield threshold. The margin between the average pumping rate in the Subbasin over the base period (46,455 AFY) and the stated sustainable rate of 72,000 AFY provides an ability to meet short-term surface water supply shortages in critically dry years through increased groundwater pumping. This is a hallmark of effective conjunctive use of surface water and groundwater resources. The projected water budget was also evaluated under climate change and sea level rise. Based on the model results, the ECC Subbasin is projected to be sustainable over the 50-year implementation and planning horizon required under SGMA. Through adaptive management, the groundwater flow detailed in Section 5 will be updated and refined to reflect actual future conditions and serve in the adaptive management of the ECC Subbasin using the best available information. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-10 Section 6 Monitoring Networks and Data Management System Monitoring networks are developed to quantify current and future groundwater conditions in the ECC Subbasin, as well as within individual GSA jurisdictions. Monitoring networks were developed for each of the six SGMA sustainability indicators. Some sustainability indicators needed to be expanded to fill data gaps and improve the ability to demonstrate sustainability and refine the hydrogeologic conceptual model. The networks include: • Groundwater Level Monitoring Network- Groundwater level data from a network of monitoring wells reflect groundwater occurrence, flow direction, hydraulic gradients between principal aquifers, and interaction between groundwater and surface water features. Dedicated monitoring wells are located within the jurisdiction of the seven GSAs. The ECC Subbasin has 55 basin-wide wells and 12 of these comprise a network of representative monitoring sites (RMS) as defined under new regulations governing GSPs. • Groundwater Storage – Groundwater levels serve as a proxy for the groundwater storage sustainability indicator monitoring network. • Seawater Intrusion – Intrusion of saline baywater, if it occurs, is evaluated based on chloride concentrations from monitoring wells adjacent to the San Joaquin River. • Groundwater Quality –Groundwater quality monitoring will be conducted at an existing network of 22 basin-wide water supply wells, 11 of these are part of a representative monitoring network. • Land Subsidence – A land subsidence monitoring network is comprised of four Plate Boundary Observatory (PBO) stations in and adjacent to the ECC Subbasin and data collected by DWR using InSAR 8 satellite data. • Interconnected Surface Water – Interconnected surface water will be monitored through existing stream gages (19) and Shallow Zone groundwater level monitoring wells (15). New shallow wells were installed as part of this GSP to address a data gap. A Data Management System (DMS) was developed to store and analyze data collected as part of this GSP. With submittal and implementation of the ECC Subbasin GSP, there will be a publicly accessible weblink to view reports, maps, graphs, and current data under the Subbasin monitoring plan. Section 7 Sustainable Management Criteria Sustainable management criteria include establishing a sustainability goal for the Subbasin, defining undesirable results, and quantifying minimum thresholds and measurable objectives. The sustainability goal for the ECC Subbasin GSP is to manage the groundwater Subbasin to: • Protect and maintain safe and reliable sources of groundwater for all beneficial uses and users. • Ensure current and future groundwater demands account for changing groundwater conditions due to climate change. 8 InSAR is Interferometric Synthetic Aperture Radar. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-11 • Establish and protect sustainable yield for the Subbasin by achieving measurable objectives set forth in this GSP in accordance with implementation and planning periods 9. • Avoid undesirable results defined in the GSP in accordance with SGMA. Sustainable management criteria (SMC) also define the conditions that constitute sustainable groundwater management. Note that undesirable results have not occurred historically in the ECC Subbasin and are not projected to occur in the future. The sustainable management criteria will commit the GSAs to meeting the sustainability goal for the Subbasin. Table ES-1 summarizes the SMC for the six SGMA sustainability indicators and includes the minimum thresholds and measurable objectives required under GSP regulations: Table ES-1 Sustainable Management Criteria Summary Sustainability Indicator Measurable Objective (MO) Minimum Threshold (MT) Undesirable Result Chronic Lowering of Groundwater Levels Average spring elevation of groundwater at the Representative Monitoring Site (RMS) and its vicinity The lowest historical water levels observed in a well plus an additional 10 feet lower The MT in any well is exceeded over three consecutive years, indicating a trend, and do not recover in normal to wet years Reduction in Groundwater Storage Use as a proxy, the MO for chronic lowering of groundwater levels Use as a proxy, the MT for chronic lowering of groundwater levels Use as a proxy, the undesirable result for chronic lowering of groundwater levels Seawater intrusion The MO at each RMS is the average chloride concentrations from 2013 to 2017. Chloride concentration for any Shallow Zone or Deep Zone well is set at 250 mg/L secondary maximum contaminant level A bayside monitoring well has a chloride concentration above 250 mg/L over three consecutive years and is determined to be induced by GSAs’ actions. Degraded Groundwater Quality The MO for each RMS is the average concentrations (2013 to 2017) for each constituent of concern The three-year running average exceedance of an MCL for a key monitoring constituent. Any RMS that exceeds any state drinking water standard during GSP implementation because of GSAs’ actions Land Subsidence The MO is set at UNAVCO station P256 at the average seasonal elastic movement (0.6 inch vertical). An MT of 1-inch land surface elevation outside the historical elastic range over a three-year period as Associated impacts due to groundwater pumping: impacts to infrastructure such as damage to roads and structures, reduced 9 As defined under SGMA, the GSP implementation period is 20 years. The planning and implementation horizon is a 50-year time period over which the GSAs determine that plans and measures will be implemented to ensure that the basin or subbasin is operated within its sustainable yield. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-12 Sustainability Indicator Measurable Objective (MO) Minimum Threshold (MT) Undesirable Result shown by monitoring data at the UNAVCO site P256. capacity of water conveyances, and increased vulnerability to flooding. Depletion of interconnected surface water The MO is set at the average annual groundwater pumping during the Base Period 1997 to 2018, or 54,000 AFY. Based on the groundwater flow model results, a conservative interim MT is set at a value for sustained basin- wide pumping above the historic baseline average which induces exceedances in estimated streamflow depletion as compared to baseline conditions. 10 Depletions that result in reductions in flow or stage of major rivers and streams that are hydrologically connected to groundwater in the Subbasin and which cause significant and unreasonable impacts on beneficial uses and users of surface water and the environment Section 8 Projects and Management Actions Projects and management actions (PMAs) were developed to achieve the ECC Subbasin sustainability goal by 2042 and avoid undesirable results during and beyond the GSP planning and implementation horizon. Because the ECC Subbasin is currently and projected to be sustainable (i.e., no onset of undesirable results), PMAs are not expected to be essential for sustainability. However, future conditions are uncertain and PMAs will be employed through the principle of adaptive management on an as-needed basis. Seven projects are included in the GSP representing a variety of project types to increase water supply availability and reliability including infrastructure to provide in-lieu recharge, improve water quality, and increase use of recycled wastewater. Projects are divided into three status categories: completed, under construction, and planned. The three completed projects are operating and provide in-lieu groundwater benefits of over 5,500 AFY. The two projects under construction will be operating by 2042 and are projected to provide over 8,000 AFY. Management actions consisting of water well policies (e.g., metering and reporting, spacing, and construction features) and demand management would be implemented locally by individual GSAs on an as-needed basis. Except for a measure designed to protect water quality, such as seal depths, such management actions are not applicable to de minimis users. 10 The interim MT for interconnected surface water will be replaced with monitored shallow groundwater levels and calculations of the rate or volume of depletion when the data gap for shallow monitoring is filled as described in Section 6. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-13 Section 9 Plan Implementation Estimated Cost to Implement the GSP The estimated total cost to the ECC GSP Working Group 11 over the first five years of GSP implementation is between $2.6 and 3.1 million. Costs are based on best available estimates. These costs include public outreach, monitoring and well maintenance, data management, and GSP reporting (e.g., annual and 5-year updates). Individual member agencies will continue to fund individual projects and/or management actions and monitoring activities. The budget will be adjusted over time as the GSP implementation costs are better understood through sustainable management activities and guidance from DWR on the submitted GSP and subsequent reporting. Implementation of the projects will be borne by the project proponents. Funding Sources and Mechanisms GSA implementation costs will be paid for through contributions from the member GSAs and CCWD under a cost-sharing arrangement to be developed following GSP adoption. Grant funding will be pursued when available. Schedule for Implementation Figure ES-3 provides a projected schedule for ECC GSP implementation including outreach and communication, monitoring, and GSP reporting activities. 11 ECC GSP Working Group consists of the seven GSAs and Contra Costa Water District. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 EXECUTIVE SUMMARY LSCE ES-14 Figure ES-3 GSP Implementation Schedule Task Name 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 Plan Implementation GSP Submittal to DWR x Joint Implementation Agreement x Outreach and Communication Monitoring and DMS GSP Reporting Annual Reports x x x x x x x x x x x x x x x x x 5-year GSP Evaluation Reports x x x x Section 10 Notice and Communication Development of the ECC GSP was a collaborative effort among the ECC GSP Working Group (seven GSAs and CCWD), technical consultants, community members, and stakeholders. The Working Group conducted over 40 meetings, from 2018 to 2021. Documents posted to a publicly accessible website, Working Group meeting notes, surveys, newspaper notices, and direct email outreach were used to keep the public informed of the GSP development and provide opportunities for public input. The Working Group members also provided regular updates through individual agency public meetings and websites. Information was also provided through social media by those agencies with a presence on such platforms. Three public workshops, held between July 2020 and September 2021, were used to inform and engage beneficial users of groundwater in the ECC Subbasin and discuss each section of the GSP. Stakeholder comments were incorporated into the final GSP. x Indicates a submittal. Indicates ongoing event. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-i SECTION 1 CONTENTS 1. Introduction ............................................................................................................................1-1 1.1. Background ................................................................................................................................ 1-1 1.1.1. Purpose of the Groundwater Sustainability Plan ............................................................... 1-1 1.1.2. Sustainability Goal .............................................................................................................. 1-1 1.1.3. Description of the East Contra Costa Subbasin .................................................................. 1-1 1.2. Agency Information ................................................................................................................... 1-2 1.2.1. GSAs in East Contra Costa Subbasin .................................................................................. 1-2 1.2.2. Agency Names and Mailing Addresses .............................................................................. 1-4 1.2.3. Agencies’ Organization, Management Structure, and Legal Authority of the GSAs and CCWD ................................................................................................................................. 1-5 1.2.3.1. City of Brentwood GSA (Plan Manager) ..................................................................... 1-5 1.2.3.2. Byron-Bethany Irrigation District GSA........................................................................ 1-6 1.2.3.3. City of Antioch GSA .................................................................................................... 1-6 1.2.3.4. Contra Costa County GSA ........................................................................................... 1-6 1.2.3.5. Contra Costa Water District ....................................................................................... 1-6 1.2.3.6. Diablo Water District GSA .......................................................................................... 1-6 1.2.3.7. Discovery Bay Community Services District GSA ....................................................... 1-6 1.2.3.8. East Contra Costa Irrigation District GSA ................................................................... 1-7 1.2.4. Governance Structure ........................................................................................................ 1-7 1.2.4.1. Memorandum of Understanding for GSP Development ........................................... 1-7 1.2.4.2. Description of Initial Notification ............................................................................... 1-7 1.3. Report Organization and Elements Guide ................................................................................. 1-8 1.4. References ................................................................................................................................. 1-9 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-ii LIST OF FIGURES Figure 1-1 East Contra Costa Subbasin, GSAs, and Adjacent Subbasins…………………………………………1-3 Figure 1-2 Management Structure, ECC Subbasin…………………………………………………………………………1-5 LIST OF APPENDICIES Appendix 1a Definitions and Key Terms (CWC 10721 and 23 CCR 351) Appendix 1b Amended and Restated Memorandum of Understanding, Development of a Groundwater Sustainability Plan for the East Contra Costa Subbasin EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-1 1. INTRODUCTION 1.1. Background 1.1.1. Purpose of the Groundwater Sustainability Plan The Sustainable Groundwater Management Act (SGMA), effective January 1, 2015, established a framework of priorities and requirements to facilitate sustainable groundwater management throughout California. The intent of the SGMA mandate is for groundwater to be managed by local public agencies (Groundwater Sustainability Agencies [GSAs]) to ensure a groundwater basin is operated within its sustainable yield through the development and implementation of a Groundwater Sustainability Plan (GSP or Plan). 1.1.2. Sustainability Goal Each GSP must include a sustainability goal for the basin to manage groundwater in a manner that avoids undesirable results within 20 years of the statutory deadline (i.e., by or before January 31, 2042). “Undesirable result means one or more of the following effects caused by groundwater conditions occurring throughout the basin” (Water Code §10721.x): 1 Chronic lowering of groundwater levels indicating a significant and unreasonable depletion of supply if continued over the planning and implementation horizon. Overdraft during a period of drought is not sufficient to establish a chronic lowering of groundwater levels if extractions and groundwater recharge are managed as necessary to ensure that reductions in groundwater levels or storage during a period of drought are offset by increases in groundwater levels or storage during other periods. 2 Significant and unreasonable reduction of groundwater storage. 3 Significant and unreasonable seawater intrusion. 4 Significant and unreasonable degraded water quality, including the migration of contaminant plumes that impair water supplies. 5 Significant and unreasonable land subsidence that substantially interferes with surface land uses. 6 Depletions of interconnected surface water that have significant and unreasonable adverse impacts on beneficial uses of the surface water. As required by SGMA regulations, the ECC GSAs developed a sustainability goal for the Subbasin that is described in detail in Section 7. Definitions for terms used in SGMA from the California Water Code 10721 and the California Code of Regulations Title 23 351 are included in Appendix 1a. 1.1.3. Description of the East Contra Costa Subbasin The original boundary of the Tracy Groundwater Subbasin included the jurisdiction of multiple cities and the counties of Contra Costa and San Joaquin. To streamline the development of the required GSP, the GSAs in Contra Costa and San Joaquin Counties, on September 6, 2018 applied to the State to divide the Tracy Subbasin along the border of Contra Costa and San Joaquin Counties. Dividing a groundwater basin is known as a Basin Boundary Modification or BBM. This allows the GSAs in each County to develop their own GSP under the Act. On February 11, 2019, the Department of Water Resources approved dividing the EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-2 Tracy Subbasin into two subbasins (e.g., East Contra Costa Subbasin and the new Tracy Subbasin) thereby creating a separate groundwater basin entirely within Contra Costa County. The East Contra Costa Subbasin (ECC Subbasin), also referred to as San Joaquin Valley-East Contra Costa (5-022.19), is a medium priority groundwater basin based on the Groundwater Basin Prioritization by the State Department of Water Resources (DWR) (Figure 1-1). Under SGMA, medium priority subbasins must submit an adopted GSP by January 31, 2022. The ECC Subbasin’s boundaries are generally defined by the San Joaquin River on the north, Old River on the East, the Contra Costa County boundary on the south, and the non-water bearing geologic units on the west. As mentioned above, the ECC Subbasin is contained entirely within Contra Costa County and underlies all or portions of the Cities of Antioch, Oakley, Brentwood, the Town of Discovery Bay and the communities of Bethel Island, Byron and Knightsen. 1.2. Agency Information 1.2.1. GSAs in East Contra Costa Subbasin In the East Contra Costa Subbasin, eight agencies are working together in developing the GSP. The agencies include: • Byron Bethany Irrigation District (BBID) • City of Antioch • City of Brentwood • Contra Costa County (CCC) • Contra Costa Water District (CCWD) • Diablo Water District (DWD) • Discovery Bay Community Services District (DBCSD or TODB) • East Contra Costa Irrigation District (ECCID) SGMA authorizes a “local public agency that has water supply, water management, or land use responsibilities within a groundwater subbasin or basin to elect to become a GSA and to develop, adopt, and implement a GSP (Water Code § 10721(n).)” All agencies listed above became GSAs with the exception of CCWD. CCWD is a water district that provides surface water to entities within their service area. Surface water may play a part in future management of a groundwater basin and so CCWD is an equal partner in the development of the ECC GSP. On May 9, 2017, the eight agencies entered a Memorandum of Understanding (MOU). Under this MOU the agencies share costs and management of the development and implementation of the GSP. In addition, the MOU was updated with the subbasin name change as a result of the BBM in March 2020 when the eight agencies signed an updated MOU to develop a GSP (Appendix 1b). Prior to the basin boundary modification, the Tracy Subbasin was successful in obtaining one million dollars in Proposition 1 Round 2 grant funds for GSP development. After the BBM, the ECC and Tracy Subbasins split the grant funding to prepare a GSP for each of the two subbasins. On October 24, 2019, San Joaquin County and the City of Brentwood signed an agreement for the management of the grant funds. In addition, the ECC Subbasin received Proposition 68 Round 3 funding. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-3 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-4 1.2.2. Agency Names and Mailing Addresses As per California Water Code §10723.8, the following contact information is provided for each GSA. City of Brentwood GSA (Plan Manager) Attention: Water Operations Manager Public Works Operations Eric Brennan 2201 Elkins Way Brentwood CA, 94513-7344 ebrennan@brentwoodca.gov Byron Bethany Irrigation District Attention: Assistant General Manager 7995 Bruns Road Byron, CA 94514-1625 City of Antioch GSA Attention: Project Manager 200 H Street Antioch, CA 94509 Contra Costa County GSA Attention: Manager, Contra Costa County Water Agency 30 Muir Road Martinez, CA 94553 Diablo Water District GSA Attention: General Manager P.O. Box 127 87 Carol Lane Oakley, CA 94561 Discovery Bay Community Services District GSA Attention: General Manager 1800 Willow Lake Road Discovery Bay, CA 94505-9376 East Contra Costa Irrigation District GSA Attention: General Manager 1711 Sellers Avenue Brentwood, CA 94513 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-5 1.2.3. Agencies’ Organization, Management Structure, and Legal Authority of the GSAs and CCWD The seven (7) GSAs that cover the ECC Subbasin and participate in the development and administration of the GSP each have their own organization and management structure and legal authority as described below. Prior to becoming a GSA, each entity submitted notifications to DWR as outlined in Water Code §10723.8. GSA boundaries are shown in Figure 1-1, and the ECC Subbasin management structure is shown in Figure 1-2. The GSA Working Group is made up of GSA representatives plus a representative from CCWD that meet monthly to coordinate GSP development. The organization and management structure for the seven GSAs and CCWD (an equal partner and financial contributor) are described below. 1.2.3.1. City of Brentwood GSA (Plan Manager) The City of Brentwood GSA operates within its current city organization and management structure as a General Law City. Government Code section 36501 authorizes general law cities be governed by a city council of five members (Mayor, Vice Mayor, and three Council Members). Bentwood’s GSA activities are staffed through the City’s Public Works Department and one member attends the monthly GSA Working Group meeting that coordinates GSP activities. The person with management authority for implementation of the Plan is the City Manager or designee. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-6 1.2.3.2. Byron-Bethany Irrigation District GSA Byron-Bethany Irrigation District GSA operates within its current organization and management structure under its seven-member Board of Directors and its legal authority as a multi-county special district, operating under Division 11 of the California Water Code. It was originally created to deliver raw, agricultural water to area farmers. The District elected to serve as the GSA for the portion of BBID that is situated within the boundaries of the ECC Subbasin. A portion of BBID is also within the adjacent Tracy Subbasin. The General Manager sits on the GSA Working Group that coordinates ECC Subbasin GSP activities. The person with management authority for implementation of the Plan is the District’s General Manager. 1.2.3.3. City of Antioch GSA The City of Antioch GSA operates within its current organization and management structure as a General Law City under its current City Council that consists of five members. Its legal authority is described in the City ordinances, and it abides by state codes. The GSA activities are staffed through the City’s Capital Improvements Division. The Project Manager of the Capital Improvements Division sits on the GSA Working Group that coordinates ECC Subbasin GSP activities. The person with management authority for implementation of the Plan is the City Manager or designee. 1.2.3.4. Contra Costa County GSA The Contra Costa County GSA operates within its current organization and management structure by a five-member Board of Supervisors as well as its legal authority set forth in the Sustainable Groundwater Management Act, California Water Code section 10720, et seq. The GSA activities are staffed through the Contra Costa County Water Agency and one member sits on the monthly GSA Working Group meeting that coordinates GSP activities. The person with management authority for implementation of the Plan is the director of the Department of Conservation and Development. 1.2.3.5. Contra Costa Water District Contra Costa Water District is not a GSA but is an equal partner and financial contributor to the development of the ECC GSP through the District’s execution of the ECC MOU. 1.2.3.6. Diablo Water District GSA The Diablo Water District GSA operates within its current organization and management structure by a five-member Board of Directors as well as its legal authority as a special district. The General Manager and staff operate the District following policies set by the Board. The General Manager and Manager of Water Operations sit on the GSA Working Group that coordinates ECC Subbasin GSP activities. The person with management authority for implementation of the Plan is the General Manager. 1.2.3.7. Discovery Bay Community Services District GSA The Town of Discovery Bay GSA operates within its current organization and management structure as a California Independent Community Services District and is governed by a five-member Board of Directors, as well as legal authority as a special district. The District’s General Manager is tasked to carry out the policy decisions of the Board and oversee day-to-day operations. The General Manager sits on the GSA Working Group that coordinates ECC Subbasin GSP activities. The person with management authority for implementation of the Plan is the General Manager. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-7 1.2.3.8. East Contra Costa Irrigation District GSA The East Contra Costa Irrigation District GSA operates within its current organization and management structure under a five-member Board of Directors representing five Divisions within the District as well as legal authority as a special district. The General Manager sits on the GSA Working Group that coordinates ECC Subbasin GSP activities. The person with management authority for implementation of the Plan is the General Manager. 1.2.4. Governance Structure Figure 1-1 shows the extent of the GSP area (the entire ECC Subbasin) and each of the seven GSA jurisdictional boundaries. The following powers and authorities are granted to GSAs to implement the GSP in accordance with the requirements of California Water Code § 10725 et seq: • Adopt standards for measuring and reporting water use • Adopt rules, regulations, policies and procedures to govern the adoption and implementation of the GSP, as authorized by SGMA including funding of the GSA, and the collection of fees or charges as may be applicable • Develop and implement conservation best management practices • Develop and implement metering, monitoring and reporting related to groundwater pumping • Hire consultants as determined necessary or appropriate by the GSA • Prepare a budget 1.2.4.1. Memorandum of Understanding for GSP Development As mentioned above, the seven GSAs and CCWD entered into a MOU on May 9, 2017. The purpose of the MOU was to collaborate to develop a single GSP for the ECC Subbasin and for each GSA to consider adopting and implementing the GSP within its GSA management area. The term of the MOU is until January 31, 2022 when the GSP is due to DWR. An updated MOU was required as a result of the BBM resulting in the new subbasin name. An updated MOU was signed on March 2020 (Appendix 1b). 1.2.4.2. Description of Initial Notification The first step in preparing a GSP is notifying DWR of the intent to develop a GSP. In February 2018, the City of Brentwood submitted an Initial Notification to prepare a GSP for the Tracy Subbasin. Although the new ECC Subbasin was formed on February 2019, the ECC GSP development efforts continued from February 12, 2018 (when the Tracy Subbasin Initial Notification was submitted). The initial Notification to DWR is posted on the DWR website: https://sgma.water.ca.gov/portal/gsp/init/all. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-8 1.3. Report Organization and Elements Guide This Report will be organized into the following sections: Section 1: Introduction Section 2: Plan Area Section 3: Basin Setting Section 4: Historical, Current, and Projected Water Supplies Section 5: Water Budget Section 6: Monitoring Network and Data management System Section 7: Sustainable Management Criteria Section 8: Projects and Management Actions Section 9: Plan Implementation Section 10: Notice and Communication DWR has provided the Elements Guide1 that lists information required to be included in a GSP by the Sustainable Groundwater Management Act and the Groundwater Sustainability Plan Emergency Regulations. It is a cross reference to where this information can be found in the GSP (e.g., page number, figure number, and/or table number). 1 Source: https://sgma.water.ca.gov/portal/resources: Printable Elements Guide Excel Template EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 1 - INTRODUCTION LSCE 1-9 1.4. References Brown and Caldwell (B&C). 2016. Final 2015 2015 Urban Water Management Plan. Prepared for City of Brentwood. June 2016. Bradford Island Reclamation District 2059. https://bradfordisland.com/. Accessed January 2020 California Department of Water Resources (DWR). 1981. Water Well Standards: State of California. Bulletin 74-81. California Department of Water Resources (DWR). 1991. California Well Standards, Bulletin 74-90. California Department of Water Resources (DWR) Well Completion Report Map Application. 2019. https://www.arcgis.com/apps/webappviewer/index.html?id=181078580a214c0986e2da28f8623b37. Accessed May 2019. California Department of Water Resources (DWR). 2019 https://gis.water.ca.gov/app/edas/. Accessed May 2019. California Department of Water Resources (DWR). 2019. https://gis.water.ca.gov/app/dacs/. Accessed May 2019. California Department of Water Resources (DWR). December 2016. Guidance Document for the Sustainable Management of Groundwater: Groundwater Sustainability Plan (GSP) Annotated Outline. https://water.ca.gov/LegacyFiles/groundwater/sgm/pdfs/GD_GSP_Outline_Final_2016-12-23.pdf. Accessed on March 26, 2020. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-i SECTION 2 CONTENTS 2 Plan Area .................................................................................................................................2-1 2.1 Description of Plan Area ...................................................................................................................2-1 2.1.1 Summary of Jurisdictional Areas and Other Features (§354.8 a and b) .......................... 2-1 2.1.1.1 Adjudicated Areas and Areas Covered by an Alternative GSP......................................... 2-1 2.1.1.2 Cities and County Jurisdictions ........................................................................................ 2-1 2.1.1.3 Water Agency Jurisdictions and the East County Regional Water Management Association ....................................................................................................................... 2-4 2.1.1.4 Federal, State, Tribal, and Special District Jurisdictions .................................................. 2-8 2.1.1.5 Major Water Related Infrastructure ................................................................................ 2-8 2.1.1.6 Sacramento-San Joaquin River Delta (the Delta) ........................................................... 2-11 2.1.2 Density of Wells ............................................................................................................. 2-12 2.2 Water Resources Monitoring and Management Programs (10727G) (§354.8c, d, and e) ......... 2-19 2.2.1 CASGEM and Historical Groundwater Level Monitoring ............................................... 2-19 2.2.2 Department of Water Resources (DWR) and EWM ....................................................... 2-21 2.2.3 Groundwater Ambient Monitoring and Assessment Program (GAMA) ........................ 2-21 2.2.4 GeoTracker ..................................................................................................................... 2-21 2.2.5 California Division of Drinking Water (DDW) ................................................................. 2-21 2.2.6 U.S. Geological Survey (USGS) ....................................................................................... 2-21 2.2.7 Subsidence Monitoring .................................................................................................. 2-21 2.2.8 Climate Monitoring ........................................................................................................ 2-23 2.2.9 Incorporating Existing Monitoring Programs into the GSP ............................................ 2-23 2.2.10 Limits to Operational Flexibility ..................................................................................... 2-23 2.2.11 Conjunctive Use ............................................................................................................. 2-23 2.3 Land Use Elements or Topic Categories of Relevant General Plans (§354.8a and f) .................. 2-24 2.3.1 Current and Historical Land Use .................................................................................... 2-24 2.3.2 Disadvantaged Area: DAC, SDAC and EDA ..................................................................... 2-28 2.3.3 Water Use Sector and Water Source Type .................................................................... 2-33 2.3.4 General Plans ................................................................................................................. 2-33 2.3.4.1 Contra Costa General Plan ............................................................................................. 2-37 2.3.4.2 City of Antioch General Plan .......................................................................................... 2-37 2.3.4.3 City of Brentwood General Plan .................................................................................... 2-37 2.3.4.4 City of Oakley General Plan ........................................................................................... 2-38 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-ii 2.3.4.5 Land Use Plans and the GSP Water Supply Assumptions .............................................. 2-38 2.3.5 Water Management Plans ............................................................................................. 2-38 2.3.5.1 Urban Water Management Plan .................................................................................... 2-38 2.3.5.2 Agricultural Water Management Plan ........................................................................... 2-38 2.3.5.3 Integrated Regional Water Management Plan .............................................................. 2-39 2.3.5.4 Additional Water Plans in Subbasin ............................................................................... 2-40 2.4 County Well Construction, Destruction and Permitting .............................................................. 2-40 2.4.1 Wellhead Protection and Well Permitting ..................................................................... 2-40 2.4.1.1 Well Installations ........................................................................................................... 2-40 2.4.1.2 Well Abandonment ........................................................................................................ 2-41 2.4.1.3 Well Destruction ............................................................................................................ 2-41 2.5 Additional Plan Elements (WCS 10727.4) ..................................................................................... 2-42 2.6 References ..................................................................................................................................... 2-43 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-iii LIST OF TABLES Table 2-1 Region Water Management Group Members and Primary Function ............................. 2-4 Table 2-2 Types of Wells ................................................................................................................ 2-19 Table 2-3 Land Use Summary ........................................................................................................ 2-24 Table 2-4 Area Summary of Disadvantaged Areas ........................................................................ 2-29 Table 2-5 Population Summary of Disadvantaged Areas .............................................................. 2-30 Table 2-6 Additional Plan Elements ............................................................................................... 2-42 LIST OF FIGURES Figure 2-1 East Contra Costa Subbasin, GSAs, and Adjacent Subbasins ........................................... 2-2 Figure 2-2a Jurisdictional Boundary, Cities, Counties and Agencies with Water Management Responsibilities……………………………………………………………………………………………………………2-3 Figure 2-2b Jurisdictional Boundaries, Wastewater Agencies ............................................................ 2-7 Figure 2-3 Jurisdictional Boundaries, State, Federal Lands, and Special Districts ............................ 2-9 Figure 2-4 Water Related Infrastructure......................................................................................... 2-10 Figure 2-5a Legal Delta Boundary ..................................................................................................... 2-13 Figure 2-5b Legal Delta Boundary – Primary and Secondary Zones ................................................. 2-14 Figure 2-6a Domestic Well Density per Square Mile ........................................................................ 2-15 Figure 2-6b Production Well Density per Square Mile...................................................................... 2-16 Figure 2-6c Public Supply Well Density per Square Mile .................................................................. 2-17 Figure 2-6d Agricultural Well Density per Square Mile..................................................................... 2-18 Figure 2-7 ECC CASGEM Monitoring Network ................................................................................ 2-20 Figure 2-8 Stream Gauges and Climate Stations ............................................................................. 2-22 Figure 2-9 Land Use-2014 & 2015 ................................................................................................... 2-25 Figure 2-10 Historical Land Use -1995 .............................................................................................. 2-26 Figure 2-11 Historical Land Use -1976 .............................................................................................. 2-27 Figure 2-12 Land Use Summary ........................................................................................................ 2-28 Figure 2-13a Summary of Disadvantaged Areas by Area .................................................................... 2-31 Figure 2-13b Summary of Disadvantaged Areas by Population .......................................................... 2-32 Figure 2-14 Land Use by Water Sector ............................................................................................. 2-34 Figure 2-15 Land Use by Water Source (2010) ................................................................................. 2-35 Figure 2-16 Relevant General Plans in ECC Subbasin........................................................................ 2-36 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-1 2 PLAN AREA 2.1 Description of Plan Area 2.1.1 Summary of Jurisdictional Areas and Other Features (§354.8 a and b) The ECC Subbasin (Subbasin) covers a 168 square mile area (107,596 acres) in the eastern portion of Contra Costa County, spans 18 miles from north to south and ranges from four to 13 miles from east to west, and includes seven communities: Antioch, Bethel Island, Byron, Brentwood, the Town of Discovery Bay (TODB), Knightsen, and Oakley. Three (Antioch, Brentwood and Oakley) are incorporated cities, Discovery Bay is a California Community Services District, Bethel Island is a Special Act District created by the California State legislature (1960) and named the Bethel Island Municipal Improvement District, the remaining two (Byron, and Knightsen) are census designated places. The Subbasin lies within the northwestern portion of the larger San Joaquin Valley Groundwater Basin. The Subbasin is bound by the Coast Range to the west and other groundwater subbasins to the northwest (Pittsburg Plain, DWR Subbasin 2-004), north (Solano Subbasin, DWR Subbasin 5-021.66), northeast (Eastern San Joaquin Basin, DWR Subbasin 5-022.01), and to the south and east (Tracy Subbasin, DWR Subbasin 5-022.15) (Figure 2-1). All adjacent subbasins are required to submit a GSP with the exception of Pittsburg Plain Subbasin (due to a “Very Low” basin prioritization that does not require a GSP to be completed). 2.1.1.1 Adjudicated Areas and Areas Covered by an Alternative GSP This GSP covers the entire ECC Subbasin and is managed by seven exclusive GSAs (Figure 2-1). There are no known adjudicated areas within the ECC Subbasin or any areas covered by an Alternative GSP. 2.1.1.2 Cities and County Jurisdictions Figure 2-2a shows city and county boundaries, and agencies with water management responsibilities. Apart from GSAs in the Subbasin, no other agencies have direct authority over groundwater, though Contra Costa County permits and regulates wells and septic systems throughout the Subbasin, including the cities, pursuant to Contra Costa County Ordinance code. Contra Costa Water District (CCWD) is a public water entity in Contra Costa County (County) but with no direct authority over groundwater within the Subbasin. Each City regulates land use within their city and the County regulates land use in the unincorporated areas of the Subbasin. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-2 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-3 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-4 2.1.1.3 Water Agency Jurisdictions and the East County Regional Water Management Association The water agencies in East Contra Costa County are listed below with a description of their authorities and responsibilities. Each of the GSAs in the Subbasin belong to the East County Regional Water Management Association, in some capacity. Because of this association there is a long history of collaboration in water management decisions in the region. Table 2-1 outlines the thirteen agencies joined together to form the Regional Water Management Group and their primary function (IRWMP, 2015). Seven of those members are GSAs, and they are described in more detail below. Table 2-1. Regional Water Management Group Members and Primary Function1 Member Agency Water Supply/ Quality Wastewater Recycled Stormwater/ Flood Management Watershed/ Habitat City of Antioch X X X X X City of Brentwood X X X X X Byron-Bethany Irrigation District X X2 Contra Costa County Flood Control X X Contra Costa County X X X Contra Costa Resource Conservation District X X Contra Costa Water District X X Delta Diablo X X Diablo Water District X Discovery Bay Community Services District X X X East Contra Costa County Habitat Conservancy X X East Contra Costa Irrigation District X Ironhouse Sanitary District X X 1 Source: 2015 IRWM Plan Update 2 BBID provides management services and operations and maintenance support to the Byron Sanitary District, which provides wastewater and sewer services to Byron residents. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-5 City of Antioch The City of Antioch is a public water purveyor that provides water to a population of approximately 108,000 (in 2015) within the service area (WYA, 2016); however, the City’s total service area extends outside the Subbasin. Surface water is the City’s only source of water supply and includes (for 2015, WYA, 2016): 1. surface water purchased from CCWD (12,000-acre feet per year [AFY]) 2. surface water diverted from the San Joaquin River through the City’s intake (1,200 AFY), 3. Recycled water from Delta Diablo (50 AFY). Surface water is stored in a municipal reservoir and treated at the Antioch Water Treatment Plant. Recycled water is used to irrigate four parks and its municipal golf course. The City does not use groundwater for water supply, nor does it expect to use groundwater by the year 2040 (WYA, 2016). City of Brentwood The City of Brentwood is a public water purveyor that provides water to a population of over 56,000 within the service area (B&C, 2016). The City’s service area within the Subbasin is a subset of its total service area. The City’s annual supply includes: 1. surface water purchased from CCWD (4,720 AFY pumped to the Randall Bold Water Treatment Plant (RBWTP) from the Rock Slough intake via the Contra Costa Canal), 2. groundwater from seven active wells with a capacity of 7,000 AFY), 3. surface water from ECCID (entitlement of 14,800 AFY pumped from Rock Slough through the Contra Costa Canal for treatment at the City of Brentwood Water Treatment Plant [COBWTP]) (B&C, 2016). In drought years, the City relies upon groundwater more than in normal years. Byron-Bethany Irrigation District (BBID) BBID provides agricultural water to southeastern CCC. It is a public agency governed by an elected board of directors and was established for the purpose of providing water to the lands within Alameda County, Contra Costa and San Joaquin Counties. In 2012, BBID served 5,663 acres within CCC and delivered 18,484 AF of water (IRWIM, 2015). In 2014, CCWD began coordination with BBID to install an intertie between Byron Division Canal 45 and the CCWD Old River pipeline. This will facilitate water transfers with CCWD and/or storage of BBID water in the Los Vaqueros Reservoir for later use in the northern portions of the Byron Division. By July 2015, a portion of the project had been implemented. In 2015, 214 AF of groundwater from growers’ wells was used to supplement surface water during the drought. Though some private pumping occurs, landowners predominantly rely on surface water allocation in the Byron and Bethany Divisions (AWMP, 2015). Contra Costa Water District (CCWD) The CCWD was formed in 1936 to provide water for irrigation and industry. It is currently one of California’s largest urban water districts that provides untreated and treated water to municipal, residential, commercial, industrial, landscape irrigation, and agricultural customers. It draws its water from the Delta primarily under a contract with the federal Central Valley Project (CVP). CCWD manages the Los Vaqueros Reservoir. The Contra Costa Canal is the backbone of CCWD conveyance system that was originally owned by the U.S. Bureau of Reclamation (USBR). CCWD is currently taking ownership of the Canal (expected by 2022) and will continue to operate and maintain the facility. Water is supplied to the canal from Rock Slough as well as from Old and Middle Rivers via pipelines. One of CCWD’s two water treatment plants is located in the Subbasin (e.g., RBWTP in Oakley [jointly with DWD]). CCWD supplies water to the Cities of Antioch and Brentwood and Diablo Water District. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-6 Diablo Water District (DWD) DWD was established in 1953 to provide water to customers in downtown Oakley and now serves the City of Oakley, the Town of Knightsen, and some of Bethel Island. It serves a population of about 42,000 people in a 21 square mile area (e.g., Oakley, Cypress Corridor, Hotchkiss Tract, and Summer Lakes, Bethel Island, and Knightsen). The majority (about 80% per CDM Smith, 2016) of water delivered is surface water supplied by CCWD and treated in RBWTP 1 (owned jointly with CCWD). Two municipal wells supplement DWD’s surface water source providing about 2,000 AFY (CDM Smith, 2016). East Contra Costa Irrigation District (ECCID) ECCID is an independent special district established in 1926 to provide agricultural irrigation water to properties within ECCID (IRWM, 2019). ECCID boundaries include the City of Brentwood, and portions of the Cities of Oakley and Antioch and the unincorporated community of Knightsen. ECCID has a 1912 appropriative right to divert water from Indian Slough on Old River and also operates nine groundwater wells (IRWM, 2019). In 2012, ECCID pumped about 330 AF of groundwater. Town of Discovery Bay Community Services District (TODB) The TODB was formed in 1998 to provide over 15,000 residents with water, treatment, distribution, and storage. All the water supply is from six groundwater supply wells (IRWM, 2019) pumping about 3,000 AFY. Other Agencies Ironhouse Sanitary District (ISD) maintains sanitary services for nearly 30,000 customers in the Oakley and Bethel Island area (Figure 2-2b). Water is treated at its facility in Oakley California and recycled water is spread on its 3,600-acre Jersey Island fields, which are used for grazing of cattle. In addition, the fields are used for wildlife and habitat for waterfowl. ISD processes 4,800 AFY of recycled water and half is spread on ISD fields near the Oakley facility on Jersey Island to water hay fields and the other half is released into the San Joaquin River (SJR). Delta Diablo (DD) District provides wastewater treatment and recycled water production for the City of Antioch, Bay Point and Pittsburg, however, only the City of Antioch is in the Subbasin. It treats 15,000 AFY of water (2016) and releases the treated water into New York Slough. It provides about 9,000 AFY of recycled water (treated domestic wastewater used more than once) used for cooling two power generating plants and irrigation of two golf courses and 12 city parks in the DD service area (Figure 2-2b). Bethel Island Municipal Improvement District (BIMID) is responsible for maintaining levees and drainage on Bethel Island but also has the authority to create and maintain parks and playgrounds https://bimid.com/about-bimid/). 1 Randall Bold Water Treatment Plant EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-7 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-8 Byron Sanitary District2 encompasses the unincorporated community of Byron and serves a population of 800. It is an independent special district with a five-member board of directors, and a General Manager. The wastewater treatment and disposal facility is located on 30 acres of land with 8 acres of evaporation ponds and 10 acres irrigated with treated effluent. Small Water Systems Small water systems and mutual water companies supply drinking water to communities between 2 and 199 service connections; or serve 25 or more people at least 60 days per year (days/yr). Three areas in the Subbasin (Bethel Island [twelve systems], Oakley [six systems], and Byron [four systems]) have small community water systems (15 to 199 service connections) that rely on groundwater as the only water supply source (IRWM, 2019, pg 2-31). Small community water systems are regulated by Contra Costa Environmental Health 3. 2.1.1.4 Federal, State, Tribal, and Special District Jurisdictions Other entities have authority and responsibilities within the Subbasin that need to be considered when developing a GSP. Figure 2-3 shows Federal-owned and state-owned lands and the agency with jurisdiction over the land. Dutch Slough (managed by DWR) is 1,187 acres of land that is being transformed into tidal marsh to provide habitat for salmon and other native fish and wildlife. In addition, the map includes lands owned and managed by East Bay Regional Park District (a special district) that preserves natural and cultural resources in Alameda and Contra Costa Counties. There are no known federally designated tribal lands or tribes in the Subbasin. The Sonoma Northwest Information Center (NWIC) (Sonoma State) searched for sacred lands, and none were found in the area. The Native American Heritage Commission (NAHC) record search returned no information for the Subbasin. NAHC further recommended contacting individual tribal leaders and provided a list of seven people for the GSAs to contact. On April 18, 2019, a separate email was sent to each person recommended by NAHC requesting information on whether there was knowledge of sacred lands in the vicinity of the Subbasin, followed by a phone call. To date, we received no responses identifying federally designated tribal lands in the East Contra Costa Subbasin. 2.1.1.5 Major Water Related Infrastructure Major water-related infrastructure in the Subbasin Figure 2-4 is relied upon by multiple cities, water agencies and private water users. These facilities deliver supplies to GSA members and to the State Water Project (SWP) including the California Aqueduct and the Delta Mendota Canal. 2 Source: https://contracostasda.specialdistrict.org/byron-sanitary-district-3715f00 3 In addition to small community water systems listed above there are also Local Small Water Systems (2-4 connections), State Small Water Systems (5-14 connections), as well as non-community public water systems all regulated by Contra Costa Environment Health. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-9 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-10 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-11 Contra Costa Water District Facilities The Contra Costa Water District facilities in the ECC Subbasin are shown on Figure 2-4. CCWD jointly owns RBWTP with DWD which has been operated by CCWD since the plant came online in 1992. Raw water is conveyed to the RBWTP from the Rock Slough intake via the Contra Costa Canal (operated by CCWD) as well as from the Old River and Middle River intakes via pipelines. Water can be stored in the Los Vaqueros Reservoir from the Old River and Middle River intakes during periods of low salinity (winter and spring) in the Delta. It is then later used (late summer and early fall) to blend with raw water from the Rock Slough intake when high salinity conditions are experienced in the Delta. Surface water supplies for the City of Brentwood originate from Rock Slough. The supply is transported through the Contra Costa Canal for treatment at the City of Brentwood Water Treatment Plant (COBWTP). CCWD supplies water to the City of Antioch from diversions at the Middle River (Victoria Canal), Rock Slough, and Old River. The Los Vaqueros Reservoir Phase 2 Expansion project would increase capacity from 160,000 to 275,000-acre feet and is scheduled for completion by 2027. This expansion will improve water supply reliability while protecting Delta fisheries. Byron-Bethany Irrigation District Facilities BBID service area is both within the ECC Subbasin (Byron Division) and in the Tracy Subbasin (Bethany Division, raw water service area (RWSA) 1 and 2, and CVP Service Area). The water supply distribution system for the Byron, Bethany Divisions and RWSA1 includes pump stations on the intake channel at the Harvey O. Banks Pumping Plant (Figure 2-4). BBID Pump 1 diverts the District’s pre-1914 water supply north to the Byron Division and south to the Bethany Division and RWSA 1. State Water Project (SWP) Clifton Court Forebay is part of the SWP and serves as the starting point of the California Aqueduct, which delivers water to Southern California. In addition, it provides water via the Delta-Mendota Canal to the San Joaquin Valley. The Harvey O. Banks Pumping Plant at Clifton Court Forebay lifts the water from the Delta into the California Aqueduct (Figure 2-4). Eleven pumps at the Banks Pumping Plant (2.5 miles southwest of Clifton Court Forebay) pull water from Old River. This water has been diverted from the Sacramento River near Walnut Grove (via Delta Cross Channel and Snodgrass Slough) to the Mokelumne River into the SJR and then south up Old River. 2.1.1.6 Sacramento-San Joaquin River Delta (the Delta) The Sacramento-San Joaquin Delta is the center of California’s water supply, providing fresh water to the majority of the state’s population and to millings of acres of farmland. It is the largest estuary on the West Coast and provides critical habitat to fish and wildlife species. The East Contra Costa Groundwater Subbasin is located on the southwestern part of the Delta. The Delta is a 1,300 square mile area where the Sacramento, San Joaquin, and Mokelumne Rivers come together that was once a tule marsh. In the mid to late 1800s and early 1900s, settlers installed a levee system that formed many of the islands. When the islands were dewatered for agricultural development, land subsidence resulted from oxidation of organic soils, some Delta Islands in the Subbasin have lowered more than 15 feet in response to peat oxidation (not related to groundwater extraction). Problems facing the delta are compounding because subsiding delta islands and rising sea levels would increase pressure on the levees and rising sea level would and push salt water further into the delta. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-12 The Delta is composed of three zones. The Primary Zone is the center of the Delta (Figure 2-5a, b), the largest zone (490,050 acres) and is primarily rural farmland but includes a few small towns4. The Secondary Zone includes 247,320 acres of farmland and cities and suburbs. The third area (Suisun Marsh) is northwest of the Primary Zone and not discussed in this section. Two state agencies have land use jurisdiction in the Delta: Delta Stewardship Council described in the Delta Plan, 2013, and the Delta Protection Commission (DPC). The Council and the DPC have concurrent jurisdiction in the Delta’s Primary Zone to ensure that local land use planning is consistent with their own laws and plans. About two-thirds of the islands and tracts in the Sacramento-San Joaquin Delta are below sea level and are surrounded by levees that protect the land from floods and high tides. There are more than 1,100 miles of levees in the delta contracted to protect farmland. The predominant land use of the islands in the ECC Subbasin is agriculture with a small population of farm workers. Agencies with responsibilities for levee maintenance and drainage systems in the Subbasin include: BIMID, RD 2024 (Orwood and Palm Tracts), RD 2025 (Holland Tract), RD 2026 (Webb Tract), RD 2059 (Bradford Island), RD 2065 (Veale Tract), RD 2090 (Quimby Island), RD 2121 (Bixler Tract), RD 2137 (Dutch Slough Restoration Project site), RD 799 (Hotchkiss Tract, planned residential development and ecological restoration project), RD 800 (Byron Tract and Discovery Bay), RD 830 (Jersey Island owned by ISD and recycled water used to grow hay). 2.1.2 Density of Wells The density of different well types provides a general distribution of agricultural, industrial and domestic well users and identify communities dependent on groundwater; another tool to understand groundwater use in the Subbasin. Well data and well construction information were obtained from DWR’s well completion report database, ECC pumping records, and from DWR’s Well Completion Report Map Application (DWR, 2019). DWR Well Completions Report Map Application is an interactive mapping tool that displays submitted well completions reports. DWR categorizes wells in the mapping application as either domestic, production and public supply, and this database was used to create Figures 2-6a, b, and c. Figure 2-6a illustrates the well density of domestic wells by each Public Land Survey System (PLSS) township-range and section (typically a 1-mile by 1-mile square grid). This map indicates that the highest density of domestic wells occurs along an east-west swath between Knightsen and Brentwood, as well as near Byron. The domestic wells are considered de minimis extractors, pumping less than two AF annually and would collectively pump less than 2,000 AFY. Figure 2-6b illustrates the well density of production wells per square mile and shows the highest density of these types of wells to be located in the vicinity of Oakley, Knightsen, and Brentwood, with others located in the Town of Discovery Bay and Byron. DWR defines “production wells” as “those wells that are designated as irrigation, municipal, public, or industrial on Well Completion Reports”. Figure 2-6c illustrates the well density of public supply wells, with the highest density of public supply wells occurring in the Town of Discovery Bay. The DWR database allows the wells to be filtered for planned use and wells with the designation of Irrigation-Agriculture are illustrated on Figure 2-6d with the highest density of these wells om the Knightsen/Oakley area. 4 The Delta Plan, Ensuring a reliable water supply for California, a healthy Delta ecosystem, and a place of enduring value. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-13 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-14 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-15 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-16 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-17 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-18 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-19 The DWR well completion database contains over 5,000 wells historically drilled in the Subbasin. The DWR mapping application estimates the number of wells in ECC at approximately 1,180 wells. The difference between the two sources is thought to be due to wells that are inactive or destroyed. Table 2-2 summarizes well types by use for the wells in the DWR Well Completion Report Map Application. Based on DWR’s map application, the estimated well density ranges from approximately 1 to 68 wells per square mile, but as stated above, there are uncertainties associated with the DWR well coverage that may double count wells and/or include missing and incorrect values. Table 2-2. Types of Wells1 Type of Well Total Wells Domestic 975 Production 156 Public Supply 51 Agricultural 136 TOTAL 1,182 1DWR SGMA Data Viewer – Well Reports Statistics in ECC Subbasin; downloaded on May 9, 2019 2.2 Water Resources Monitoring and Management Programs 5 (10727G) (§354.8c, d, and e) 2.2.1 CASGEM and Historical Groundwater Level Monitoring The East Contra Costa County California Statewide Groundwater Elevation Monitoring (CASGEM) Network tracks seasonal and long-term groundwater level trends. The ECC CASGEM Network began in 2011 and is managed by DWD; it was updated in 2014 and updated again in 2018. Figure 2-7 displays the CASGEM network of 27 wells by monitoring entity. In addition, BBID, DWD, ECCID, and TODB voluntarily share groundwater depth data for over an additional 20 wells. Once the GSP is implemented it will replace the CASGEM Monitoring Plan. The GSP monitoring well groundwater levels will be entered into the SGMA Monitoring Network Module (MNM) instead of CASGEM. However, voluntary or non-SGMA wells data will still upload the CASGEM Operating System. Historically, groundwater levels have been monitored by various agencies since the 1950s. Numerous reports were prepared to evaluate these data and groundwater conditions in the basin and include: An Initial investigation of Ground Water Resources (LSCE, 1999) that serves as a baseline for future groundwater conditions reports, DWD Groundwater Management Plan (GMP) (LSCE, 2007), and Groundwater Quality Monitoring Plan (GQMP) (LSCE, 2018). 5 It is not clear at this time how these programs will change with the development and implementation of the GSPs. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-20 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-21 2.2.2 Department of Water Resources (DWR) and EWM DWR takes annual measurements (spring and fall) in three wells in the ECC Subbasin that are included in the Subbasin CASGEM well network. In addition, DWR manages the EWM (it used to be called the Water Data Library and then CASGEM). The EWM includes historical groundwater level measurements since the early 1900s and periodic water quality data. 2.2.3 Groundwater Ambient Monitoring and Assessment Program (GAMA) As part of the GAMA program, the State Water Resources Control Board (SWRCB) collects data from water agencies and private well owners and makes it available to the public. The data aide interpretation of groundwater quality and monitoring efforts. 2.2.4 GeoTracker The SWRCB provides data for sites that have impacted water quality including groundwater. These records contain not only general mineral and contaminated constituent concentrations but also groundwater levels. 2.2.5 California Division of Drinking Water (DDW) Formerly the Department of Health Services, DDW is a division of the SWRCB that regulates public drinking water systems. They asses the quality of the drinking water and identify specific water quality problems. Public water system (PWS) wells are to meet Title 22 water quality requirements and DDW provides these PWS data to the public. 2.2.6 U.S. Geological Survey (USGS) USGS monitors wells for water levels and water quality generally for special projects (i.e., not on a regular monitoring schedule). The USGS makes the data available for public on the National Water Information System (NWIS) website. The USGS maintains a series of stream gauges in the vicinity of the Subbasin. Fifteen of the USGS stream gauges have historical data and are currently active in the Subbasin (Figure 2-8). 2.2.7 Subsidence Monitoring Subsidence monitoring in the Subbasin consists of a Continuous Global Positioning System (CGPS) station managed by the Plate Boundary Observatory/UNAVCO. These stations were generally constructed to monitor motions caused by plate tectonics, but they are also used for other applications (e.g., assessing subsidence). UNAVCO GPS (P256) is located in the ECC Subbasin with measurements starting in 2005. Additional subsidence monitoring in adjacent subbasins includes DWR Surveying/spirit leveling (Solano and Yolo Subbasin), USGS Interferometric Synthetic-Aperture Radar (InSAR) (Delta-Mendota Subbasin), and an extensometer in the Yolo Subbasin. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-22 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-23 2.2.8 Climate Monitoring The locations for two climate stations (Antioch and Brentwood) are shown on Figure 2-8. Climate is discussed in more detail in Chapter 5 of the GSP. 2.2.9 Incorporating Existing Monitoring Programs into the GSP The existing monitoring programs listed above will provide the basis for the GSP monitoring program. Specifically, the CASGEM Network will provide the foundation of groundwater level data, as described in more detail in Chapter 3.3 of this document that describes the GSP Monitoring Program. In addition, the GSP monitoring program will incorporate production well water quality data as well as monitoring data from existing stream gauges. 2.2.10 Limits to Operational Flexibility The existing monitoring programs are not anticipated to limit the operational flexibility of this GSP. The current groundwater monitoring programs will form the basis of the future GSP monitoring program. This includes some CASGEM wells for water levels, proposed dedicated groundwater monitoring wells (water level and quality), DDW monitoring for water quality and existing subsidence monitoring stations as appropriate. No existing groundwater management or monitoring programs are expected to limit the operational flexibility of the groundwater Subbasin. 2.2.11 Conjunctive Use The majority of water used in the ECC Subbasin is surface water (e.g., the City of Antioch purchases surface water only from CCWD and has a water right to river diversion water). Conjunctive use programs (coordinated use of surface water and groundwater) in the ECC Subbasin are currently implemented and planned by individual agencies. CCWD receives its water from the Sacramento-San Joaquin Delta and in recent years it has used Los Vaqueros Reservoir to help improve water quality and as an emergency supply resource (LSCE, 2007). The City of Brentwood primarily receive surface water deliveries and pump groundwater on an as needed basis. TODB operates solely on groundwater and has multiple pumping wells in the town’s boundary. DWD uses 80% surface water (CVP provides water and DWD also purchases surface water) and has the capacity to pump groundwater to meet up to 20% of the demand in its service area. Both ECCID and BBID are able to operate fully on surface water in nearly all water years. ECCID has groundwater wells in its area to help meet water demands as needed. In 2000, the two agencies entered an agreement with CCWD that allows them to sell water to CCWD during drought years and allows CCWD to purchase a smaller amount in non-drought years (LSCE, 2007). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-24 2.3 Land Use Elements or Topic Categories of Relevant General Plans (§354.8a and f) Land use is a key factor in determining water demand. Changing land use conditions and irrigation practices are also factors that affect water demand from year to year. 2.3.1 Current and Historical Land Use General land use conditions based on DWR survey data for CCC are illustrated in Figures 2-9 through 2-11 and summarized in Table 2-3 and Figure 2-12. The 2015 land use in the Subbasin is mainly agricultural (41%), followed by urban (about 23%), then by water and native vegetation (both about 14%) (source: DWR Crop Mapping Delta 2015 geospatial dataset 6). The crop types with the highest land use coverage in the Subbasin are pasture (14%) and field crops (12%). Outside of the Subbasin, the existing land use is mainly field crops, truck crops and pasture (Figure 2-9) in the delta area. Table 2-3. Land Use Summary Land Use Designation 1976 1995 2015 acres % acres % acres % Field Crops Total1 23,153 22% 18,195 17% 13,467 13% Idle 916 1% 5,754 5% 3,527 3% Native2 25,040 23% 23,400 22% 15,581 15% Fruit/Nut Trees & Citrus/Subtropical Trees 12,057 11% 6,398 6% 1,947 2% Pasture 12,979 12% 11,087 10% 14,809 15% Semi-agricultural3 797 1% 868 1% 6,276 6% Truck Crops 7,747 7% 6,800 6% 5,428 5% Urban4 9,726 9% 19,231 18% 23,523 23% Vineyards 848 1% 876 1% 1,980 2% Water 14,368 13% 14,868 14% 14,926 15% Total5 107,632 100% 107,477 100% 101,462 100% Source and Abbreviations: California Open Data Portal, https://data.ca.gov/dataset/crop-mapping-delta-2015, accessed June 2019. Also used 2014 data for areas not covered by 2015 mapping. California Department of Water Resources, https://water.ca.gov/Programs/Water-Use-And-Efficiency/Land-And- Water-Use/Land-Use-Surveys, accessed June 2019 1- Includes land designated as Grain and Hay in 1976. 2- Includes land designated as Native, Native Riparian, Native Vegetation. 3-Includes incidental to agricultural, farmsteads, feed lots, dairies, lawns, cemeteries. 4- Includes land designated as Recreation in 1976. 5-Total area differs due to different survey areas monitored. Total about 107,000 acres (168 square miles). 6-1995 and 2015 Surveys have land that was not surveyed and was given "Not Designated" description. 6 California Open Data Portal, https://data.ca.gov/dataset/crop-mapping-delta-2015, accessed June, 2019. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-25 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-26 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-27 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-28 Figures 2-10 and 2-11 illustrate historical land use for the years 1995 and 1976, respectively. Table 2-3 and Figure 2-12 summarize land use trends over a 40-year span (1976 to 2015) that shows increasing urban lands and decreasing agricultural (field crops and fruit trees) and native lands. Chapter 4.1 provides additional detail on current and historical land uses. 2.3.2 Disadvantaged Area: DAC, SDAC and EDA Nearly 35% of the ECC Subbasin is considered a Disadvantaged Area and (Table 2-4 and Figure 2-13a), which accounts for almost 20% of the population of the Subbasin (Table 2-5 and Figure 2-13b). The term “Disadvantaged Area” includes the severely disadvantaged communities (SDAC), disadvantaged communities (DAC), and economically distressed areas (EDA), (collectively referred to as Disadvantaged Area [DA]). There are 15,253 people in 5,610 acres of land in the ECC Subbasin that are categorized as a DAC, an additional 17,689 people in 5,095 acres are designated as SDACs, making approximately 18% of the 178,618 population and 10% of the 107,600 acres of the ECC Subbasin covered by DACs and SDACs. DACs are areas identified as having a median household income (MHI) of less than 80% of the California statewide annual MHI, and SDACs have an MHI of less than 60% of the statewide MHI. The DAC/SDAC acreage is based on the Median Household Income ($63,783) for 2012-2016 US Census American Community Survey (ACS) and in accordance with data from DWR’s DAC Mapping Tools. The areas within EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-29 the Subbasin identified as DACs and SDACs are displayed on Figure 2-13. A summary of DAC area by Census geography type (e.g., Census Block Groups, Census Place, and Census Tracts) is included in Table 2-4. There are 2,645 people in 26,389 acres of land in the ECC Subbasin that are categorized as an EDA. The areas within the Subbasin identified as EDAs are displayed on Figure 2-13a, and 2-13b. A summary of EDA areas by Census geography type (i.e., by Tracts and Blocks) is included in Table 2-4 (by area) and Table 2-5 (by population). The EDAs by Tract and Block fulfill three criterion: EDA Criterion 1 and 2 municipality with MHI of less than 85% of the Statewide MHI and a population of less than 20,000; and EDA Criterion 3 has a low population density (less than or equal to 100 persons/square mile). The total percentage of people in the Subbasin comprising EDAs is about 2% and 24.5% percent of land are considered EDAs. Table 2-4. Summary of Disadvantaged Areas by Area Area Description Acres1 Percent of Subbasin Cumulative Acres1 Cumulative Percent of Subbasin East Contra Costa Subbasin 107,596 100% 107,596 100% Disadvantaged Communities2 Census Block Groups SDAC 1,512 1.41% 1,512 1.41% DAC 3,218 2.99% 4,730 4.40% Census Place SDAC 3,583 3.33% 8,313 7.73% Census Tracts DAC 2,392 2.22% 10,705 9.95% Total Census Block Group and Tract DACs & SDACs 10,705 9.95% Economically Distressed Areas3 Census Tract and Block Total EDA 26,389 24.53% 26,389 24.53% Total DACs, SDACs, and EDAs for All Census Geographies 37,095 34.5% 1 Areas calculated using geographic projection NAD 1983 California Teale Albers. 2 DAC = Disadvantaged Community: $38,270 < median household income [MHI] < $51,026. SDAC = Severely Disadvantaged Community: MHI < $38,270 (60% of statewide MHI). 3 EDA=Economically Distressed Area: a municipality with a population of 20,000 persons or less, a rural county, or a reasonably isolated and divisible segment of a larger municipality where the segment of the population is 20,000 persons or less, with an annual median household income that is less than 85% of the Statewide median household income, and with one or more of the following conditions as determined by the department: (1) financial hardship, (2) unemployment rate at least 2% higher than the Statewide average, or (3) low population density. (Water Code §79702(k)). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-30 Table 2-5. Summary of Disadvantaged Areas by Population Area Description Population1 Percent of Subbasin Cumulative Population1 Cumulative Percent of Subbasin East Contra Costa Subbasin 178,618 100% 178,618 100% Disadvantaged Communities2 Census Block Groups SDAC 15,490 8.67% 15,490 8.67% DAC 13,684 7.66% 29,174 16.33% Census Place SDAC 2,199 1.23% 41,373 17.56% Census Tracts DAC 1,569 0.88% 32,942 18.44% Total Census Block Group and Tract DACs & SDACs 32,942 18.44% Economically Distressed Areas3 Census Tract and Block Total EDA 2,645 1.48% 2,645 1.48% Total DACs, SDACs, and EDAs for All Census Geographies 35,587 19.9% 1 Population calculated using Census Tract data. 2 DAC = Disadvantaged Community: $38,270 < median household income [MHI] < $51,026. SDAC = Severely Disadvantaged Community: MHI < $38,270 (60% of statewide MHI). 3 EDA=Economically Distressed Area: a municipality with a population of 20,000 persons or less, a rural county, or a reasonably isolated and divisible segment of a larger municipality where the segment of the population is 20,000 persons or less, with an annual median household income that is less than 85% of the Statewide median household income, and with one or more of the following conditions as determined by the department: (1) financial hardship, (2) unemployment rate at least 2% higher than the Statewide average, or (3) low population density. (Water Code §79702(k)). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-31 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-32 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-33 2.3.3 Water Use Sector and Water Source Type SGMA regulations define “water use sector” as “categories of water demand based on the general land uses to which the water is applied, including urban, industrial, agricultural, managed wetlands, managed recharge, and native vegetation7.” Figure 2-14 shows the distribution of the water use sectors in the Subbasin. Agriculture is the predominant water use sector followed by urban (Cities of Antioch, Oakley, Brentwood, and Discovery Bay) and native vegetation. The Subbasin has three water source types: surface water (primary source about 80,000 AFY); groundwater (secondary source about 8,000 AFY); and recycled water (about 2,700 AFY) (IRWMP, 2019, based on 2010 Urban Water Management Plans). Land use by water source in the ECC Subbasin is shown in Figure 2-15. Conjunctive use of surface water and groundwater is practiced throughout much of the Subbasin. Urban centers water sources vary The City of Antioch uses surface water exclusively, while the Cities of Brentwood and Oakley (water provided by DWD) use a combination of surface water and groundwater, and the Town of Discovery Bay uses only groundwater. ECCID and BBID hold water rights to divert surface water from Old River and meet remaining demand with groundwater. The unincorporated portions of the Subbasin generally have surface water as the water source however, these amounts are not quantified. The exceptions to this are domestic users and small community water systems which rely on groundwater. The Ironhouse Sanitary District uses recycled water to irrigate crops for animal feed on Jersey Island (2,700 AF in 2010). 2.3.4 General Plans Four entities in the ECC Subbasin have land use authority8 (Figure 2-16), which is an important factor in water management. Below is a description of the plans and how they may affect implementing the GSP. The Town of Discovery Bay does not have land use authority; however, the Town can advise the County on decisions affecting land use. The following section describes policies in the Plans related to water resources management in the ECC Subbasin. General Plans in the ECC Subbasin include:  Contra Costa County General Plan (CCCDCD,2005)  City of Antioch General Plan (LSA, 2003)  City of Brentwood General Plan (DNPG, 2014)  City of Oakley General Plan (CoO, 2016) 7 California Code of Regulations, Title 23. Waters, Division 2. Department of Water Resources, Chapter 1.5. Groundwater Management, Subchapter 2. Groundwater Sustainability Plans, Article 2. Definitions 8 CC County -Title 8, Zoning https://library.municode.com/ca/contra_costa_county/codes/ordinance_code?nodeId=TIT8ZO City of Brentwood – Title 17, Zoning http://qcode.us/codes//brentwood/?view=desktop&topic=17-viii-17_467-17_467_002 City of Antioch – Title 9, Planning and Zoning https://codelibrary.amlegal.com/codes/antioch/latest/overview City of Oakley – Title 9 Land Use Regulation https://www.codepublishing.com/CA/Oakley/ EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-34 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-35 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-36 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-37 2.3.4.1 Contra Costa General Plan The planned land use for the Subbasin is outlined in the Contra Costa County General Plan (CCCGP). The CCCGP was developed for 2005 to 2020 (CCC, 2005). Currently the county is working on a comprehensive update to the General Plan; a draft is anticipated to be ready for review in 2021. The county is mandated by California Government Code (§65350-65362) to prepare a General Plan to help and guide future development in the county as related to land use, development, and conservation. It describes that much of the county’s future growth (2000 to 2010) was planned along the Pittsburg-Antioch corridor. In regard to conservation the CCCGP developed five overall policies: • 8-1. Resource utilization and development shall be planned within a framework of maintaining a healthy and attractive environment. • 8-2. Areas that are highly suited to prime agricultural production shall be protected and preserved for agriculture and standards for protecting the viability of agricultural land shall be established. • 8-3. Watersheds, natural waterways, and areas important for the maintenance of natural vegetation and wildlife populations shall be preserved and enhanced. • 8-4. Areas designated for open space/agricultural uses shall not be considered as a reserve for urban uses and the 65 percent standard for non-urban uses must not be violated. • 8-5. In order to reduce adverse impacts on agricultural and environmental values, and to reduce urban costs to taxpayers, scattered urban development in outlying areas shall be precluded outside the urban limit line. 2.3.4.2 City of Antioch General Plan The City of Antioch prefers that development not outpace infrastructure. The City foresees that a lot of development will occur in the area and requires developers to pay for infrastructure improvements so current infrastructure will not be overly stressed. The City also wants the infrastructure to be outlined prior to completing development to avoid want temporary work arounds. The City anticipates more growth, and its goal is to continue water conservation efforts. The City presents several options to meet water demands besides conservation. These include (LSA, 2003): • Confirm new developments can be supported with a reliable water source • New development landscaping must be drought tolerant • Work to make recycled water a viable option • Protect potential groundwater recharge areas • Fight policies that would reduce river rights (i.e., increase salinity) 2.3.4.3 City of Brentwood General Plan The City of Brentwood General Plan was updated in 2014 (DNPG) and provides the framework to guide growth and conserve open space. The City’s goal with regard to water requirements is to provide safe and reliable water to its citizens. The General Plan outlines three ways it plans to achieve this goal. The City plans to continually assess water saving strategies and water demands. The City also plans to discuss the possibility of receiving additional water from East Bay Municipal Utility District (EBMUD), CCWD, and ECCID. In 2006, voters approved an Urban Limit Line (ULL); the line would limit the development of urban infrastructure. Current land use maps show small areas are planned for future development (DNPG, 2014). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-38 2.3.4.4 City of Oakley General Plan The City of Oakley also has a ULL and a desire to “preserve quality of life for residents”. The City’s goal to meet current and future water requirements is to require new development to detail how water supplies will be met, request that water agencies meet quality standards, and protect water sources from pollution by working with regulatory agencies. The City also will urge water agencies to have written plans in case of drought (CoO, 2016). 2.3.4.5 Land Use Plans and the GSP Water Supply Assumptions In general, land use and water supply assumptions included in the General Plans in the ECC Subbasin are consistent with current and future land use and water demand projections used in the GSP. The county and cities’ policies include water conservation and sustainable management of groundwater resources. GSP implementation is expected to be consistent with future water use and land use as projected in the General Plans, urban water management plans, and agricultural water management plans. These documents were used to project future land use and resulting water demand for the future water budgets used in the GSP. 2.3.5 Water Management Plans Many water management plans cover the Subbasin. These are described below.: 2.3.5.1 Urban Water Management Plan Urban Water Management Plans (UWMP) are required by the Urban Water Management Plan Act for any water supplier distributing more than 3,000 AFY or that has more than 3,000 connections. A UWMP must be prepared and submitted to DWR every 5 years. Each UWMP should asses the reliability of water for the next 20 years, how demands are met including shortages, conservation efforts with the goal being a 20% reduction in water use per person, and finally a goal for recycled water use in the agency’s sphere of influence. The following UWMPs have been developed in the Subbasin: • City of Antioch Urban Water Management Plan (WYA, 2015) • City of Brentwood Urban Water Management Plan (B&C, 2016) • Diablo Water District 2015 Urban Water Management Plan (CDM, 2015) • Town of Discovery Bay Community Services District 2015 Urban Water Management Plan (LSCE, 2017) • Contra Costa Water District Urban Water Management Plan (CCWD, 2015) 2.3.5.2 Agricultural Water Management Plan Agricultural Water Management Plans (AWMP) are required by the Water Conservation Act of 2009 (SB X7-7) for any water supplier distributing more than 25,000 AFY (excluding recycled water deliveries) to prepare a plan and submit it to DWR. The Act requires that each agency/region develop a water budget for a water year identifying inflow and outflow components, ways to improve water efficiency, quantify water use, and outline a plan for droughts. In addition, the AWMP must include the status of Efficient Water Management Practices (EWMP). EWMP must be followed for delivery point measurements and volumetric pricing; the remaining EWMPs are to be implemented if they are technically feasible or funding is available. The following AWMP was developed in the Subbasin: • Byron Bethany Irrigation District Agricultural Water Management Plan (CH2M, 2017) EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-39 2.3.5.3 Integrated Regional Water Management Plan In an effort to address California’s water supply and management practices, DWR created policies that encourage Integrated Regional Water Management Plans (IRWMP) and grant funding to implement the program. The goal of the IRWMP is to evaluate all aspects of water management. In 2015, CCC updated their IRWMP (ECCWMA, 2015). Their plan has 25 objectives that are used by the ECCWMA members to address their water management issues:  Protect/improve source water quality  Maintain/improve regional treated drinking water quality  Maintain/improve regional recycled water quality  Increase understanding of groundwater quality and potential threats to groundwater quality  Meet current and future water quality requirements for discharges to the Delta  Limit quantity and improve quality of stormwater discharges to the Delta  Manage local stormwater  Improve regional flood risk management  Enhance understanding of how groundwater fits into the water portfolio and investigate groundwater as a regional source (e.g., conjunctive use)  Protect, restore and enhance habitat in the Delta and connected waterways  Protect, restore and enhance the watersheds that feed and contribute to the Delta ecosystem  Minimize impacts to the Delta ecosystem and other environmental resources  Reduce greenhouse gas emissions  Protect Delta ecosystem against habitat disruption due to emergencies, such as levee failure  Increase shoreline access for subsistence fishing and recreation  Increase regional cost efficiencies in treatment and delivery of water, wastewater, and recycled water  Develop projects with regional benefits that are implementable and competitive for grant funding  Use financial resources strategically to maximize return on investment on grant applications for project development/implementation  Develop a funding pool to self-fund regional efforts such as grant applications, outreach, website development, and other planning activities  Increase public awareness of project importance to pass ballot measures or obtain matching funds through other means that require public support  Ensure projects with existing matching funds are prioritized to maximize regional funding opportunities  Identify and engage DACs  Collaborate with and involve DACs in the IRWM process  Promote equitable distribution of proposed projects across the region  Increase awareness of water resource management issues and projects with the general public EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-40 2.3.5.4 Additional Water Plans in Subbasin The City of Brentwood developed and updated a Water Master Plan in 2003 and 2017 (Ennis, 2017). The plan has two main goals: 1) identify limitations of the current water system and whether current infrastructure could be modified to resolve any deficiencies, and 2) identify what infrastructure will need to be modified to serve new development. In 2012, the TODB developed a Water Master Plan (LSCE, 2012). The plan has two main objectives 1) evaluate system efficiency, and 2) outline any capital improvement projects that would enable TODB to meet the current and future water demands of the service area. CCWD prepares a Water Management Plan to be submitted to the USBR as part of their contract for CVP water. CCWD prepares a Water Management Plan (Plan) every five years (the last one was submitted in 2017) and also periodically prepares a Future Water Supply Study. The intent of the Plan is for CCWD to demonstrate federal water “is put to reusable and beneficial use.” CCWD demonstrates this to USBR by outlining water conservation efforts, providing information on water-related infrastructure, and description of the district which includes district demographics, topography, climate, natural and cultural resources, district rules and regulations, and billing and pricing. As a result of Assembly Bill (AB) 3030, the California Water Code (CWC), Section 10750, DWD board of directors agreed to prepare a groundwater management plan. DWD’s goal was “to provide a management framework for maintaining a high quality, reliable, and sustainable supply of groundwater within the District’s sphere of influence.” In 2007, DWD implemented the Diablo Water District Groundwater Management Plan for AB 3030 (LSCE, 2007). 2.4 County Well Construction, Destruction and Permitting 2.4.1 Wellhead Protection and Well Permitting Wellhead protection is governed by county, state and federal regulations within the Subbasin. Well permitting in the Subbasin is overseen by the CCC Health Services, Environmental Health Division. The Environmental Health Division requires a Well Permit Application to be completed prior to any ground surface breaking that includes well construction, reconstruction, or destruction, including water wells, dewatering wells, monitoring wells, cathodic protection wells, geothermal wells, piezometers, inclinometers, soil vapor probes, Cone Penetrating Testing (CPTs), soil borings, and geotechnical borings. Environmental Health Division reviews the well permit and either approves, denies, or requests modification. CCC also has well regulations to meet water supply demands for new housing construction (CCC, 1981). 2.4.1.1 Well Installations A county official reviews permits for new well construction, and the application will be approved, dismissed, or more information will be requested. The well must be installed by a licensed C-57 Driller that maintains current registration with the county. Well installation requirements follow the standards outlined in the California Well Standards, Bulletin 74-81 and 74-90. The bulletin discusses the proper well locations (i.e. distance from property line, septic tanks, streams, livestock) for water supply wells, proper approaches for sealing the annulus (materials, methods, conditions and placement), casing material, and the material/construction of the completion monument (flush or stick up, with respect to the ground EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-41 surface). A county official is required to inspect the grout mixture prior to well completion, and it is the responsibility of the driller to schedule the inspection. A pump test might be required if the county determines the need for one in the area. 2.4.1.2 Well Abandonment As per Section 21 of Bulletin 74-81: A well is considered 'abandoned' or permanently inactive if it has not been used for one year, unless the owner demonstrates intention to use the well again. In accordance with Section 24400 of the California Health and Safety Code, the well owner shall properly maintain an inactive well as evidence of intention for future use in such a way that the following requirements are met: (1) The well shall not allow impairment of the quality of water within the well and groundwater encountered by the well. (2) The top of the well or well casing shall be provided with a cover that is secured by a lock or by other means to prevent its removal without the use of equipment or tools, prevent unauthorized access, prevent a safety hazard to humans and animals, and prevent illegal disposal of wastes in the well. The cover shall be watertight where the top of the well casing or other surface openings to the well are below ground level, such as in a vault or below known levels of flooding. The cover shall be watertight if the well is inactive for more than five consecutive years. A pump motor, angle drive, or other surface feature of a well, when in compliance with the above provisions, shall suffice as a cover. (3) The well shall be marked so as to be easily visible and located and labeled so as to be easily identified as a well. (4) The area surrounding the well shall be kept clear of brush, debris, and waste materials.” 2.4.1.3 Well Destruction A permit must be submitted to the agency for approval of well destruction. The county states its requirements are as follows: (1) Remove any obstructions from the well. (2) Perforate or remove the well casing to the bottom of the well. (3) Excavate around the casing to a depth of 6 ft. (4) Place approved sealing material in the well extending from the bottom to the surface. Environmental Health staff will inspect this stage of the work. The well contractor is responsible for contacting Contra Costa Environmental Health to schedule inspection appointments. The greater the advance notice, the more likely a mutually convenient inspection appointment can be arranged. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-42 2.5 Additional Plan Elements (WCS 10727.4) Table 2-6 lists the additional Plan Elements listed in Water Code Section 10727.4 that should be included in a GSP, where appropriate, and the location in the GSP where these are addressed. Table 2-6. Additional Plan Elements Section Number Code Description Section in GSP with M ore D etail 10727.4 (a) Control of saline water intrusion. 3.3.4 10727.4 (b) Wellhead protection areas and recharge areas. 2.4.1 and 3 10727.4 (c) Migration of contaminated groundwater. 3.3.6 10727.4 (d) A well abandonment and well destruction program. 2.4 10727.4 (e) Replenishment of groundwater extractions. 3 10727.4 (f) Activities implementing, opportunities for, and removing impediments to, conjunctive use or underground storage. 2.2 10727.4 (g) Well construction policies. 2.4 10727.4 (h) Measures addressing groundwater contamination cleanup, groundwater recharge, in-lieu use, diversions to storage, conservation, water recycling, conveyance, and extraction projects. 3 and 4 10727.4 (i) Efficient water management practices, as defined in Section 10902, for the delivery of water and water conservation methods to improve the efficiency of water use. 4 and 8 10727.4 (j) Efforts to develop relationships with state and federal regulatory agencies. 8 10727.4 (k) Processes to review land use plans and efforts to coordinate with land use planning agencies to assess activities that potentially create risks to groundwater quality or quantity. 8 10727.4 (l) Impacts on groundwater dependent ecosystems. 3.3.9 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-43 2.6 References Brown and Caldwell (B&C). 2016. Final 2015 2015 Urban Water Management Plan. Prepared for City of Brentwood. June 2016. Bradford Island Reclamation District 2059. https://bradfordisland.com/. Accessed January 2020 California Department of Water Resources (DWR). 1981. Water Well Standards: State of California. Bulletin 74-81. California Department of Water Resources (DWR). 1991. California Well Standards, Bulletin 74-90. California Department of Water Resources (DWR) Well Completion Report Map Application. 2019. https://www.arcgis.com/apps/webappviewer/index.html?id=181078580a214c0986e2da28f8623b37. Accessed May 2019. California Department of Water Resources (DWR). 2019 https://gis.water.ca.gov/app/edas/. Accessed May 2019. California Department of Water Resources (DWR). 2019. https://gis.water.ca.gov/app/dacs/. Accessed May 2019. California Department of Water Resources (DWR). December 2016. Guidance Document for the Sustainable Management of Groundwater: Groundwater Sustainability Plan (GSP) Annotated Outline. https://water.ca.gov/LegacyFiles/groundwater/sgm/pdfs/GD_GSP_Outline_Final_2016-12-23.pdf. Accessed on March 26, 2020. CDM Smith (CDM). 2015. Final 2015 Diablo Water District Urban Water Management Plan. June 2016. CH2M. 2017. Byron Bethany Irrigation District Agricultural Water Management Plan. Prepared for Byron Bethany Irrigation District. October 2017. Contra Costa County (CCC). 1981. Ordinance Code of Contra Costa County, California, Approved Water Supply Systems. Contra Costa County Department of Conservation and Development (CCCDCD). 2005. Contra Costa County General Plan 2005-2020. January 18,2005 Contra Costa County Environmental Health Division (CCCEHD). 1994. Well Destruction Guidelines. https://cchealth.org/eh/land-use/#Wells. Accessed May, 2019 Contra Costa County Environmental Health Division (CCCEHD). 2000. The Well Permit Process. https://cchealth.org/eh/land-use/#Wells. Accessed May, 2019 Contra Costa County Environmental Health Division (CCCEHD). 2018. Underground Storage Tanks Program. https://cchealth.org/hazmat/ust/. Accessed January 2020. Contra Costa Water District. 2015. 2015 Urban Water Management Plan for the Contra Costa Water District. June 2016. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 2 – PLAN AREA LSCE 2-44 Contra Costa Water District. 2017. Water Management Plan Report to the United States Bureau of Reclamation on Contra Costa Water District’s Water Conservation Program and Activities. City of Oakley (CoO). 2010. City of Oakley 2020 General Plan. February 2, 2016. De Novo Planning Group (DNPG). 2014. City of Brentwood General Plan. July 22, 2014. East Contra Costa County Water Management Association (ECCWMA). 2015. East Contra Costa County Integrated Regional Water Management Plan (IRWMP). March 2019. Ennis Consulting. 2017. City of Brentwood Water Master Plan. June 1, 2017 Hotchkiss Tract Reclamation District 799. https://www.rd799.com/. Accessed January 2020 Jersey Island Reclamation District 830. http://www.ironhousesanitarydistrict.com/211/RD-830. Accessed January 2020 Luhdorff and Scalmanini, Consulting Engineers. 1999. Investigation of Ground-Water Resources in the East Contra Costa Area. Prepared for East County water entities. March 1999. Luhdorff and Scalmanini, Consulting Engineers. 2007. Diablo Water District Groundwater Management Plan for AB3030. Prepared for Diablo Water District. May 2007. Luhdorff and Scalmanini, Consulting Engineers. 2011. Groundwater Monitoring Report. Prepared for Diablo Water District. August 2011. Luhdorff and Scalmanini, Consulting Engineers. 2012. Discovery Bay Community Services District Water Master Plan Final Report. January 2012. Luhdorff and Scalmanini, Consulting Engineers. 2014. California Groundwater Elevation Monitoring (CASGEM) Network Plan. Prepared for East Contra Costa Agencies. July 2014. Luhdorff and Scalmanini, Consulting Engineers. 2017. 2015 Urban Water Management Plan Town of Discovery Bay Community Services District. June 21, 2017. Luhdorff and Scalmanini, Consulting Engineers. 2018. Groundwater Conditions Update Tracy Subbasin. Prepared for Contra Costa County Agencies. May 2018. LSA Associates (LSA). 2003. City of Antioch General Plan. November 24,2003. West Yost Associates (WYA). 2016. Final 2015 Urban Water Management Plan, prepared for City of Antioch. May 2016. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING - LSCE 3-i SECTION 3 CONTENTS 3. Basin Setting ...........................................................................................................................3-1 3.1 Overview .................................................................................................................................... 3-1 3.2 Hydrogeologic Conceptual Model ............................................................................................. 3-1 Regional Geological and Structural Setting ........................................................................ 3-1 Topographic Information ............................................................................................... 3-5 Depositional Model ........................................................................................................ 3-5 Surficial Geology and Geological Formations ................................................................ 3-5 Faults and Structural Features ........................................................................................... 3-7 Basin Boundaries ................................................................................................................ 3-7 Geologic Cross Sections and Depositional Facies Model ................................................. 3-10 Principal Aquifers and Aquitards ..................................................................................... 3-14 Soil Characteristics ........................................................................................................... 3-15 Soil Properties .............................................................................................................. 3-15 Groundwater Recharge and Discharge Areas .................................................................. 3-20 Imported Supplies ............................................................................................................ 3-26 Surface Water Bodies ....................................................................................................... 3-26 Hydrogeologic Conceptual Model Data Gaps and Uncertainty ....................................... 3-26 3.3 Groundwater Conditions ......................................................................................................... 3-28 Groundwater Levels ......................................................................................................... 3-28 Groundwater Elevation Contours .................................................................................... 3-36 Storage ............................................................................................................................. 3-41 Seawater Intrusion ........................................................................................................... 3-41 Groundwater Quality ....................................................................................................... 3-46 Groundwater Contamination Risk ................................................................................... 3-57 Groundwater Contamination Sites .............................................................................. 3-58 Oil and Gas Wells ......................................................................................................... 3-58 Land Subsidence............................................................................................................... 3-61 Interconnected Surface Water Systems .......................................................................... 3-65 Groundwater Dependent Ecosystems ............................................................................. 3-67 Evaluation of GDE Health ............................................................................................. 3-74 3.4 Summary .................................................................................................................................. 3-83 3.5 References ............................................................................................................................... 3-85 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING - LSCE 3-ii LIST OF TABLES Table 3-1 Estimates of Total Groundwater Storage (2018) .................................. ………………………3-41 Table 3-2 Water Quality Concentrations for Key Constituents ........................... ……………………….3-55 Table 3-3 Land Surface Displacement Rates at PBO Sites ....................... …………………………………..3-61 Table 3-4 Vegetation Species in the ECC Subbasin ............................................. ………………………..3-73 LIST OF FIGURES Figure 3-1a Surficial Geology and Faults ........................................................................ …………………..3-2 Figure 3-1b Surficial Geology Legend .................................................................................................. 3-3 Figure 3-1c Surficial Geology Legend………………………………………………………………….………………………….3-4 Figure 3-2 Topography and Surface Water Features ........................................................................ 3-6 Figure 3-3 Basin Boundary – Jurisdictional and Natural ................................................................... 3-8 Figure 3-4 Base of Freshwater .......................................................................................................... 3-9 Figure 3-5 Cross Section Location and Depositional Environment ................................................. 3-11 Figure 3-6a Geologic Cross Section 4-4’ ............................................................................................ 3-12 Figure 3-6b Geologic Cross Section C-C’ ........................................................................................... 3-13 Figure 3-7a Soil - Type ....................................................................................................................... 3-16 Figure 3-7b Soil - Texture .................................................................................................................. 3-17 Figure 3-7c Soil - Hydraulic Conductivity .......................................................................................... 3-18 Figure 3-7d Soil – Electrical Conductivity .......................................................................................... 3-19 Figure 3-8 Soil - Potential Recharge ................................................................................................ 3-21 Figure 3-9a Domestic Wells - Average Depth ................................................................................... 3-22 Figure 3-9b Public Supply Wells - Average Depth ............................................................................. 3-23 Figure 3-9c Agricultural Wells - Average Depth ................................................................................ 3-24 Figure 3-9d Domestic Well Depth…………………………………………………………………………………………………3-25 Figure 3-10 Surface Water Bodies and Monitoring Locations .......................................................... 3-27 Figure 3-11 Groundwater Level Monitoring Locations ..................................................................... 3-29 Figure 3-12a Selected Graphs of Groundwater Elevations- Shallow Zone ......................................... 3-30 Figure 3-12b Selected Graphs of Groundwater Elevations- Deep and Composite Zone .................... 3-31 Figure 3-13a Vertical Groundwater Gradients .................................................................................... 3-33 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING - LSCE 3-iii Figure 3-13b Vertical Groundwater Gradients ………………………………………………………………………………3-34 Figure 3-13c Nested Monitoring Well Locations ................................................................................ 3-35 Figure 3-14a Groundwater Contours Spring 2012 - Shallow Zone ..................................................... 3-37 Figure 3-14b Groundwater Contours Spring 2018 - Shallow Zone ..................................................... 3-38 Figure 3-14c Groundwater Contours Spring 2012 - Deep Zone and Composite Wells ...................... 3-39 Figure 3-14d Groundwater Contours Spring 2018 - Deep Zone and Composite Wells ...................... 3-40 Figure 3-15 The Process of Saltwater Intrusion from an Aquifer ..................................................... 3-42 Figure 3-16a Partial Cross Section Location ........................................................................................ 3-43 Figure 3-16b Partial of Cross Section A-A’ .......................................................................................... 3-44 Figure 3-16c Partial Cross Section C-C’ ............................................................................................... 3-44 Figure 3-16d Chloride Isocontours for Deep Zone .............................................................................. 3-45 Figure 3-17a Average Total Dissolved Solids ...................................................................................... 3-47 Figure 3-17b Maximum Total Dissolved Solids ................................................................................... 3-48 Figure 3-18a Average Chloride ............................................................................................................ 3-49 Figure 3-18b Maximum Chloride ........................................................................................................ 3-50 Figure 3-19a Average Nitrate .............................................................................................................. 3-51 Figure 3-19b Maximum Nitrate ........................................................................................................... 3-52 Figure 3-20a Average Arsenic ............................................................................................................. 3-53 Figure 3-20b Maximum Arsenic .......................................................................................................... 3-54 Figure 3-21a Groundwater Contamination Sites and Plumes: Open Sites ................................. ……..3-59 Figure 3-21b Groundwater Contamination Sites and Plumes: Closed Sites ....................................... 3-60 Figure 3-22 Land Subsidence Monitoring Locations ......................................................................... 3-62 Figure 3-23a Subsidence on Delta Islands .......................................................................................... 3-64 Figure 3-23b Cross-section of Subsidence and Drains on Delta Island ............................................... 3-65 Figure 3-24 Surface Water Features and Subsurface Drains ............................................................ 3-66 Figure 3-25a Depth to Shallow Groundwater – Spring 2018 .............................................................. 3-68 Figure 3-25b Interconnected Surface Water-Minimum Depth to Water Spring 2018 ....................... 3-69 Figure 3-26a Groundwater Dependent Ecosystems-Vegetation .................................. …………...………3-70 Figure 3-26b Groundwater Dependent Ecosystems-Wetlands .......................................................... 3-71 Figure 3-27 Critical Habitat Map ....................................................................................................... 3-72 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING - LSCE 3-iv Figure 3-28a Normalized Difference Vegetation Index-1997 ............................................................. 3-76 Figure 3-28b Normalized Difference Vegetation Index-2004 ............................................................. 3-77 Figure 3-28c Normalized Difference Vegetation Index-2010 ............................................................. 3-78 Figure 3-28d Normalized Difference Vegetation Index-2015 .................................... ………………………3-79 Figure 3-28e Normalized Difference Vegetation Index-2018 .............................. …………………………….3-80 Figure 3-28f Normalized Difference Vegetation Index-Big Break ........................... ………………………..3-81 Figure 3-28g Normalized Difference Vegetation Index-Marsh Creek ……………………………………………..3-82 APPENDICES Appendix 3a Investigation of Ground-water Resources in East Contra Costa Area, 1999 Appendix 3b An Evaluation of Geological Conditions, East Contra Costa County, 2016 Appendix 3c Well Construction Table Appendix 3d Groundwater Level Hydrographs Appendix 3e Historical Groundwater Elevation Contour Maps Appendix 3f Groundwater Quality Table Appendix 3g Groundwater Quality Graphs (TDS, EC, Cl, NO3, As) Appendix 3h Groundwater Contamination Sites Appendix 3i ECC Subbasin Oil and Gas Wells and Fields EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-1 3. BASIN SETTING 3.1 Overview This Basin Setting section of the East Contra Costa (ECC) Groundwater Sustainability Plan (GSP) describes the Hydrogeologic Conceptual Model (HCM) (Section 3.2) and historical and current Groundwater Conditions (Section 3.3). The sections were developed using best available science and serve as the basis upon which ECC GSAs will select management criteria to maintain sustainable groundwater conditions in the ECC Subbasin. Groundwater Sustainability Agencies (GSAs) “have the responsibility for adopting a Plan that defines the basin setting and establishes criteria that will maintain or achieve sustainable groundwater management” as detailed by DWR in the GSP regulations (Title 23 California Code of Regulations [CCR] Section 350.4e). The two main topics covered in this section include: • Hydrogeologic Conceptual Model (HCM): Section 3.2 describes the physical components of the Subbasin including the regional geology, structural properties, boundaries of the Subbasin, principal aquifer descriptions with cross sections, topographic and soil characteristics, recharge areas, and significant surface water bodies. • Groundwater Conditions: Section 3.3 provides current and historical groundwater conditions including discussions of groundwater level maps and time-series graphs, groundwater storage, seawater intrusion, groundwater quality, land subsidence, interconnected surface water systems, and groundwater dependent ecosystems. 3.2 Hydrogeologic Conceptual Model The HCM describes the geologic and hydrologic framework that governs how water moves through the ECC Subbasin. This description provides the basis to develop water budgets, monitoring networks, and ultimately a surface water/groundwater mathematical model (Section 5 of this GSP). This section includes information about the regional geologic and structural setting, lateral and vertical basin boundaries, and principal aquifers. This section is based on technical studies and maps that characterize the physical components and interaction of the surface water and groundwater systems, pursuant to Section 354.14 Hydrogeologic Conceptual Model. Information was compiled for this section from two main references: Investigation of Ground-Water Resources in the East Contra Costa Area (LSCE, 1999) and An Evaluation of Geological Conditions, East Contra Costa County (LSCE, 2016). Both reports are included in this document as Appendices 3a and 3b. Regional Geological and Structural Setting The San Joaquin Valley formed between two mountain ranges (Coast Ranges and the Sierras). The ECC Subbasin lies on the western side of the northern San Joaquin Valley portion of the Great Valley province of California. The western boundary of the Subbasin is a no flow boundary with respect to groundwater and is delineated by exposed bedrock of highly deformed Tertiary age and older marine sediments of the Coast Range Diablo Mountains. Most of the Subbasin is filled with freshwater-bearing alluvium, eroded continental sediments from the Coast Ranges, that are Quaternary in age. Surficial geology from multiple sources is provided in Figure 3-1a and a detailed legend is in Figure 3-1b and c. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-2 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-3 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-4 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-5 Topographic Information The topography of the Subbasin is generally flat with land surface elevations that slope gently downward to the east. Topographic elevations vary from about 200 feet above mean sea level (msl) in the west to less than 10 feet from msl in the delta area over a distance of about 10 miles (Figure 3-2). There are portions of the Subbasin (e.g., Delta islands) in the northeast and southeast that are below sea level. Depositional Model Regional geologic studies (Bartow, 1991; and Bertoldi and others, 1991) reported that Miocene marine deposition occurred in the area as shown by the Tertiary marine rocks exposed in the Coast Ranges. During the following Pliocene epoch, the San Joaquin Valley drained south to the ocean via the Salinas Valley. The Sacramento Valley drained westward through the Delta area, and the Coast Range locally had not yet been uplifted. Deposition may have been confined to distal fluvial plains sourced from the Sierra Nevada area, such that little sand was carried into the area. Similar aged fine-grained deposits are seen in southern Sacramento County, near Vacaville, and around Rio Vista reaching thicknesses of 2,000 to 2,500 feet. In the Quaternary (mid-Pleistocene) period, the San Joaquin Valley south of Tracy was occupied by a large freshwater lake known as Corcoran Lake. Associated with the lake was deposition of the Corcoran Clay, also termed E-Clay unit. Neither the lake nor the Corcoran Clay unit extended as far north as the ECC Subbasin distinguishing the Subbasin from other parts of the San Joaquin Valley Groundwater Basin to the south and east. At about 600,000 years ago, northern San Joaquin River drainage and local Coast Range uplift began. It is suspected that this activity marked the beginning of the alluvium deposition where coarse-grained deposits were formed and carried into the area by the San Joaquin River and from erosion of the uplifting Coast Ranges. Surficial Geology and Geological Formations Bedrock formations observed in outcrops along the western boundary of the ECC Subbasin consist of strongly deformed marine sedimentary rocks that range in age from over 63 million years (my) to 5my. The Tertiary marine rocks of sandstones, shales and mudstones dip east beneath the San Joaquin Valley with increasing depths. Because of their marine origin, well consolidated nature, and saline water, the Mesozoic and Tertiary marine rocks are not a source of fresh groundwater in the Subbasin (LSCE, 1999; 2016). Additional information about these units can be found in Appendix 3a. Overlying the Tertiary marine rocks are a sequence of Tertiary-Quaternary non-marine sedimentary deposits (Pliocene to Pleistocene). These older sediments have limited areas of exposure along the edge of the Coast Range. These deposits are not well understood in the study area, but they are believed to consist of fine-grained clays, silts, and mudstones with a few sand beds. They dip moderately to the east and northeast under the San Joaquin Valley. Limited information from a few deep water well boreholes indicate they occur from 400 feet to depths of over 1,500 feet below the San Joaquin River. The lower portion of these deposits may be equivalent to the Mehrten Formation on the east side of the San Joaquin Valley. The upper portion of these older non-marine sediments may be equivalent to the Tulare Formation to the south of the Subbasin and the Tehama Formation to the north. Water quality appears to become brackish with depth (LSCE, 1999 and 2016). Overlying the Tertiary/Quaternary non-marine sediments are the primary groundwater-bearing units in the ECC Subbasin. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-6 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-7 These Quaternary alluvium deposits are unconsolidated beds of gravel, sand, silts, and clays becoming weakly consolidated with increasing age and burial depth. The alluvium thickens eastward to over 300 feet beneath Brentwood and about 400 feet below Old River. As discussed in Section 3.2.4, the units around Brentwood are believed to have been deposited by streams forming alluvial fans of silts and clays off the uplifted Diablo Mountains. Units around Discovery Bay are believed to be stream channel deposits of coarser sands and gravels. Separation of the alluvium into distinct units is difficult using well drillers’ reports. The sand and gravel can be correlated locally, but the fine-grained sand and clays are so massive, a greater spatial correlation is not possible (LSCE, 1999). Sand and gravel beds and their distribution are discussed further in this chapter. About 600,000 years before present, Corcoran Lake formed in nearly the entire San Joaquin Valley northward to the Stockton-Tracy area. A blue lake clay was deposited across the San Joaquin Valley and is known as the Corcoran Clay or E-clay. However, as cited above, this clay unit has not been identified north of the Stockton-Tracy area into the Delta area of Contra Costa County or in the Sacramento Valley (LSCE, 2016). Faults and Structural Features Three inactive faults (Midland, Sherman, and Antioch) trend in a north-south direction across the Subbasin (Figure 3-1, dashed lines). They are not known to inhibit groundwater flow or to impact water conveyance infrastructure. The Vernalis Fault is located southeast of Clifton Court Forebay (off of the geology map, Figure 3-1). Uplift or deformation along this fault may have caused a ridge that may influence groundwater flow as discussed below. No surface expression has been noted of this fault (LSCE, 2016). Basin Boundaries The lateral extent of the ECC Subbasin is defined primarily by jurisdictional and surface water boundaries (Figure 3-3). ECC Subbasin is bounded on the north, east, and south by the Contra Costa County line, which is contiguous with the San Joaquin River (north) and Old River (east). In the west, a non-jurisdictional Subbasin boundary corresponds to the non-water bearing geologic units which form a bedrock barrier to groundwater flow. Figure 3-3 is a diagrammatic illustration of the western ECC Subbasin boundary in relation to the bedrock outcrop of older consolidated marine sediments (green, blue, and tan colors). The base of the ECC Subbasin is defined by the vertical extent of available and extractable freshwater. The base of freshwater has been mapped previously in the general area by Page (1973) and Berkstressser (1973), and in a detailed map of the ECC Subbasin constructed by LSCE (2016). The base of freshwater map prepared by LSCE (Figure 3-4) updates the delineation of freshwater resources through additional oil and gas well electric logs in Montezuma Hills, Rio Vista, and the northwestern hills of Mount Diablo (Davis et al., 2018). The base of freshwater aquifers was determined from electric log responses in thick sand beds that had high resistivity values, and the character of the spontaneous-potential (S-P). This approach distinguished zones of poor water quality within sand beds, though it did not quantify salinity. Nevertheless, the geophysical characteristics of sand beds from electric logs provide a sound estimate of the vertical extent of freshwater in the Subbasin. Deeper sandy units with low resistivity values and indeterminable S-P characteristics were considered to be non-viable as aquifers. The examination by LSCE (2016) showed the deepest base of freshwater is to the northeast and east near the Subbasin boundary (-1,000 to -1,200 feet from msl) and rising to the west to elevations of 200 feet msl. In the Clifton Court Forebay area a subsurface ridge-like feature, possibly caused by the Vernalis Fault, extends eastward from the valley edge and may influence groundwater flow around the ridge or impede any northwest flow from the south at depths below -400 feet elevation. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-8 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-9 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-10 Geologic Cross Sections and Depositional Facies Model In 1999, LSCE performed a detailed hydrogeologic study of eastern Contra Costa County groundwater. The focus of the study was the uppermost 500 feet where most water wells are completed in the region. This study included construction of cross sections from drillers’ logs and oil and gas logs to assess sand bed characteristics and their extent. Five cross sections were constructed in an east-west direction perpendicular to the Coast Range and three were drawn in a north-south direction (Figure 3-5). Two cross sections (4-4’ and C-C’, Figures 3-6a and 3-6b) are included in this report and all eight cross sections are included in Appendix 3a. These sections illustrate the ground surface, lithology associated with each well log, and the base of fresh water (LSCE, 2016). The geologic cross-sections show the interbedded and variable nature of fine- and coarse-grained sediments both laterally and vertically and throughout the study area. They illustrate in detail the primary water-bearing units for water supply purposes. Coarse-grained units were identified primarily in the upper 400 feet where the majority of public supply wells are perforated however, it was noted that the units are difficult to correlate laterally. Well information was lacking for depths below 400 feet below ground surface (bgs) but consistent with the discussion in the previous section, it was expected that the units are fine grained and become brackish at depth. From the vertical and lateral variability in sediments reflected in cross sections, general patterns in the occurrence and character of sand and gravel aquifers could be identified. These variations were explained by different depositional environments (e.g., stream and delta) as detailed below. In addition, these depositional environments were used to inform groundwater model calibration and for other quantitative purposes. From the work described above, a facies model for four depositional regions in the Subbasin was developed as part of the Subbasin HCM (Figure 3-5). The depositional regions are detailed below: Fluvial Plain This is representative of the eastern portions of the Subbasin including Discovery Bay. It is defined by a zone of well-defined, thick-bedded sands and gravels with sand thickness of generally 30 feet or more per 100 feet. The depositional environment was probably similar to that which occurs in the present-day area with northward flowing river channels, distributaries, and sloughs across floodplains of overbank areas. Deposits extend to depths of about 350 feet, below which occur largely fine-grained silts and clays with poor to brackish water quality (TODB et al., 2017). Delta Islands This is representative of the northeastern portion of Subbasin (Diablo Water District GSA and encompasses Bethel Island and vicinity). Sand and gravel beds may correlate to the Fluvial Plain, but net sand thicknesses increase northward from about 30 to 60 feet per 100 feet below Bethel Island. Sand beds exist to depths of about 300 to 350 feet bgs. There is evidence of shallow saline or brackish water that may be present in shallow sand beds below the Delta Islands. The depositional environment is interpreted as multiple stream channels meandering between islands. Channels would be active with through-flowing waters, then abandoned as new channels developed. Possibly slower stream flow and tidal fluctuations allowed thicker, fine-grained sand deposits to form. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-11 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-12 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-13 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-14 Marginal Delta Dunes This is representative of the Oakley area and defined by numerous thin to thick sand beds that are on the order of 30 to 60 feet thick per 100 feet. The depositional environment is a mixture of delta fluvial distributary channels and possibly aeolian dune fields. A surface deposit of rolling gentle hills of relic sand dunes occurs between Oakley and northern Brentwood. These sand dunes are believed to have been generated by strong winds blowing sand off the delta margins. Some deeper sand beds across the Marginal Delta Dunes area may be older dune fields. Alluvial Plain This is representative of greater Brentwood south of the Marginal Delta Dune and City of Oakley, and west of the Fluvial Plain and defined by thin sand and gravel beds with a lower sand thickness (less than 20 feet per 100 feet). The depositional environment is small streams draining eastward from the Coast Range foothills to the west. Flood flows of these streams spread out from the hills depositing fine-grained materials, possibly as mudflows with high sediment content. Stream flows deposited thicker sand and gravel beds that tended to stack upon each other causing the thicker bands of sand beds. The thicker stream deposited sand and gravel bands extend eastward until the sands either thin out or have not been reached by wells. In the north, the stream deposits appear to reach into the Marginal Delta Dunes area, blending into the sand units that are present there. Antioch and Byron Areas Due to lack of well control, these two areas could not be examined in detail. The Antioch area is poorly defined, but it appears to be a thin alluvial plain with thin sand beds overlying Plio-Pleistocene non-marine deposits. The Byron area appears to have only a few thin sand beds in a small alluvial plan area that is marginal to the Fluvial Plain region where fine-grained deposits dominate. Principal Aquifers and Aquitards Two primary aquifer zones are identified in the East Contra Costa Subbasin: an unconfined to semi- confined Shallow Zone and a semi-confined to confined Deep Zone, with clay layers separating the two. These aquifers are composed of alluvial deposits as illustrated on the representative cross sections (Figures 3-6a and 3-6b). The Shallow Zone extends from ground surface to a less permeable material (i.e., clay and silt) generally to a depth of less than 150 feet bgs. The Deep Zone directly underlies the shallow zone, is the primary production zone for public supply wells (generally 200-400 feet in depth, LSCE, 2011), and extends to the base of fresh water (a maximum of 1,200 feet from mean sea level). As indicated previously, the Corcoran Clay does not extend into the ECC Subbasin nor does a similar feature occur that separates major aquifer units. However, in the Alluvial Plain (around the City of Brentwood) there appears to be local confinement by multiple clay layers which separates shallow and deep zones (LSCE, 1999). This separation is seen through distinctive water levels (see Section 3.3.1). The Fluvial Plain (around Discovery Bay, Figure 3-6a) and Marginal Delta Dune (around Oakley) both have a confined Deep Zone with an extensive layer of clay separating a shallow zone from the deep zone that serves as the primary production aquifer. The Delta Islands area does not have clay layers separating a deep confined zone from shallower aquifer materials nor water levels that reflect it. The primary use of the Shallow Zone is by domestic wells and small community water systems which may have poorer water quality due to Bay-Delta influences. The primary use of the Deep Zone is for municipal supply (City of Brentwood, Discovery Bay and DWD) and agricultural irrigation supply (ECCID and BBID). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-15 Groundwater System Conceptualization The ECC Subbasin aquifer system is subdivided into two zones: an upper unconfined Shallow Zone that sits above discontinuous to locally continuous clay layers and, a lower semi-confined to confined Deep Zone. As illustrated in the geologic cross-sections described above, the upper 400 feet of sediments is comprised of alluvial deposits with discontinuous clay layers interspersed with more permeable coarse-grained units. Most water wells are constructed within the upper 400 feet where coarse grained units are identified. Water well information is lacking for depths below 400 feet bgs to the base of fresh water but the units are likely fine grained and become brackish at and below that depth based on the current HCM. Soil Characteristics There are many soil types found throughout the Subbasin (Figure 3-7a). The soil data were gathered from the Natural Resource Conservation Service (NRCS) as part of the Soil Survey Geographic Database (SSURGO). The data are compiled from various maps, which are updated on a yearly basis. The predominate soil types in the Subbasin are the Brentwood, Capay, Delhi, Marcuse, and Rindge series. The Brentwood series is reported to be a well-drained silty clay loam found in valleys and valley floors near Brentwood. The Capay series is noted to be a moderately well-drained clay and is found throughout the Subbasin often near the Brentwood series. The Delhi series is noted to be a somewhat excessively drained sand found primarily in Oakley and Antioch and is derived from eolian deposits. The Marcuse series is noted to be a poorly drained clay and silty clay with a small amount of sand and is found throughout the center of the Subbasin. The Rindge is noted to be a very poorly drained silty clay loam to muck, and is found along the Delta Islands (i.e., Bethel Island) and near the Old River boundary. Soil Properties Soil properties are important to the HCM to the extent that they provide a pathway for groundwater infiltration through the soil and have high or low runoff potential. This information is used to calculate surface water recharge and to estimate deep percolation for surface water/ groundwater models. Figure 3-7b illustrates the soil texture of the surficial soils found in the Subbasin as outlined by NRCS. The dominant soil textures are clay, clay loam, sand, and muck. Clays and clay loams are found throughout the Subbasin. Sand is concentrated near Antioch and Oakley in the northwestern part of the Subbasin. Muck is found in the eastern portion of the Subbasin along the Old River and the Delta Islands. Muck is defined by the NRCS as “the most highly decomposed of all organic soil material. Muck has the least amount of plant fiber, the highest bulk density, and the lowest water content at saturation of all organic material”. Figure 3-7c presents the average hydraulic conductivity 1 for soils in the Subbasin. The hydraulic conductivity of soils ranges from less than 1 ft per day to more than 15 ft per day (ft/day). The highest conductivity areas are those with soil textures of muck, sand, or loamy sand. The areas around Oakley and on the northeastern and eastern border of the Subbasin have the highest hydraulic conductivity possibly due to the occurrence of dune sands. Figure 3-7d shows the soil salinity for the Subbasin. Soil salinity is measured by electric conductivity (EC) and is measured by the amount of soluble salts in the soil. Almost the entire Subbasin has electric conductivity values of less than 2 deSiemens per meter (dS/m) which is low. Higher EC is noted in the center of the Subbasin, following a similar pattern as the distribution of the Marcuse soil, which was noted to be poorly 1 Capacity for soil to transmit water with units of Length/Time. Units used in this report are feet/day. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-16 drained clay. There is also a small area near Antioch that has ECs greater than 15 dS/m, in an area with a muck texture. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-17 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-18 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-19 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-20 Groundwater Recharge and Discharge Areas Groundwater recharge can occur from infiltration of precipitation and applied water (e.g., irrigation), surface water infiltration, subsurface inflows from outside the Subbasin, and unintentional recharge (e.g., leaky pipes). This section identifies the areas that may provide greater potential for future managed surficial recharge under the GSP implementation. Surface areas with favorable recharge potential (Figure 3-8) were evaluated using soil mapping data and the Soil Agricultural Groundwater Banking Index (SAGBI). The SAGBI provides a characterization of potential for groundwater recharge on agricultural land. The SAGBI score is based on five elements: deep percolation, root zone residence time, topography, chemical limitations, and soil surface conditions. Figure 3-8 illustrates the main areas of percolation; however, these are not the same areas as those with high hydraulic conductivity (Figure 3-7c) and high infiltration potential (Figure 3-7d). The areas with highest recharge potential are along Marsh Creek near Brentwood and Kellogg Creek in the Byron area (moderately good), and the dune sands in the Oakley area (moderately poor). However, as discussed below, water levels indicate very little space, if any, available in the aquifer for additional recharge. Due to the different depositional environments that occur in the Subbasin, there are a variety of natural recharge sources. The Alluvial Plain area is recharged from the Coast Range Foothills and groundwater moves through the Alluvial Plain and the Marginal Delta Dunes’ area. The Fluvial Plain area likely has a different recharge source from the south as a function of its fluvial setting (LSCE, 1999). Recharge for the Delta Islands may be a combination of different sources, including fluvial influence from the Delta. Groundwater discharge from the Subbasin can occur from discharge to surface water and springs, subsurface outflow from the Subbasin, and groundwater extraction by wells. Groundwater discharge from the Subbasin is from groundwater pumping (agricultural, municipal, domestic, and industrial uses). Maps of general locations of wells are provided in Figures 2-6a to 2-6d. These maps indicate that the majority of domestic wells are located in the western portion of the Subbasin, public supply wells are mostly concentrated in urban centers of Discovery Bay, Brentwood, and Oakley, and agricultural wells are located on the western side of the Subbasin. Maps of the average depths (in feet) of domestic, agricultural, and public supply wells by section are provided in Figures 3-9a to 3-9c. Domestic well depths are generally less than 200 feet bgs (Figure 3-9d). Agricultural well depths vary across the Subbasin with ranges from 60 to 800 feet bgs. Public supply wells are most commonly in the 200 to 400-foot bgs range. The USGS’s National Hydrography Dataset (NHD) maps one spring in the Subbasin located along the southwestern boundary. There are multiple springs that could be sources of recharge, in addition to streams, located in the foothills west of the Subbasin boundary (Figure 3-8). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-21 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-22 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-23 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-24 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-25 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-26 Imported Supplies Contra Costa Water District draws water from the Delta primarily under a contract with the federal Central Valley Project (CVP). Surface water is diverted at two intake locations within the Subbasin: Rock Slough and Old River (Figure 2-4). Two entities in the Subbasin purchase water from CCWD: City of Antioch and Diablo Water District. In addition, CCWD diverts and conveys ECCID surface water for the City of Brentwood. Surface Water Bodies There are a number of surface water bodies that are significant to the management of the Subbasin (Figure 3-10). The Clifton Court Forebay, Franks Tract, and Big Break are large surface water bodies in the Subbasin. Two rivers are the primary natural surface water features in the ECC Subbasin. The San Joaquin River flows from east to west along the northern edge of the Subbasin and Old River flows from north to south on the eastern edge of the Subbasin. Numerous streams from the Coast Range enter the Subbasin from the west and discharge into the Delta (ECC IRWM, 2019). Marsh Creek drains parts of Mt. Diablo and has flows impounded (stored/captured) by the Marsh Creek Reservoir. Flow and water quality information is available for 2012 to 2013 2 in connection to the Dutch Slough Project. Similar to groundwater quality, March Creek water quality analyses showed TDS and chloride that exceeded the recommended secondary MCL (500 mg/L and 250 mg/l, respectively). Kellogg Creek drains the watershed south of Marsh Creek and includes the CCWD operated Los Vaqueros Reservoir. Brushy Creek is south of Kellogg Creek and drains into Old River and Clifton Court Forebay. Hydrogeologic Conceptual Model Data Gaps and Uncertainty This section identifies the data gaps and levels of uncertainty of the information for the physical setting and characteristics of the basin and current conditions. Lithologic, water quality, and water level measurement controls exist for purposes of developing the hydrogeologic conceptual model mostly in the urban areas of Brentwood, Discovery Bay and Oakley. There are large areas in the north near Antioch and Bethel Island and in the south, west of Clifford Court Forebay, that have low well density as a result of a more rural setting. Many wells used for municipal purposes were also primarily screened to less than 500 feet bgs, which leads to uncertainty in the nature of the deeper subsurface materials. Many lithological descriptions come from drillers’ logs which are limited in quality as a function of driller’s experience and attention to detail. Geophysical logs provide the most consistent and quantitative information, but well control is highly variable as a function of current and historic groundwater use patterns. Expanded monitoring by aquifer for groundwater quality and level measurements and additional lithologic descriptions outside the urban areas would benefit development of the hydrogeologic conceptual model. 2 Hydrofocus Inc. 2014. Dutch Slough Restoration Area Surface Water Quality Monitoring Report, September 2012 to August 2013. April 11, 2014. 228 pages. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-27 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-28 3.3 Groundwater Conditions This Groundwater Conditions section describes historical groundwater conditions in the ECC Subbasin through present day. Groundwater levels and storage, seawater intrusion, groundwater and surface water quality, land subsidence, interconnected surface water, and groundwater dependent ecosystems are presented in this section. Groundwater Levels Groundwater levels provide useful data for understanding groundwater conditions and trends over time. Groundwater levels are affected by natural recharge and discharge which are in turn governed by variations in climate conditions. Groundwater pumping and water usage such as in agriculture also affect groundwater levels. Groundwater movement, as governed by regional and local gradients and aquifer properties are also reflected in groundwater levels. All factors play a role in changes in groundwater storage over time which is a primary consideration in the HCM. Groundwater level records were compiled from the various entities in the Subbasin in addition to data from Geotracker, USGS, and DWR. A small subset of wells has a long period of record for water level monitoring, but most data are relatively recent, within the last 15 years. The wells with the longest period of record have over 50 years of data and are primarily concentrated in the ECCID area (Figure 2-1). All data were reviewed and compiled in a Data Management System (DMS). Data of similar type was converted to the same units and, if applicable, the method used to gather data was noted (e.g., surveyed reference point elevations versus estimated elevations). A well was assigned an aquifer zone designation (Shallow Zone, Deep Zone, Composite, or Unknown) based on the well screen interval and/or total well depth. This well construction information is presented in Appendix 3c for over 1,100 wells in the ECC Subbasin. The contact between the Shallow Zone and Deep Zone ranges in depth from 100 and 150 ft bgs throughout the Subbasin but is generally about 120 ft bgs. Wells with screen intervals in both zones were given the designation Composite. Wells with missing well construction information were designated Unknown. Figure 3-11 illustrates the groundwater level monitoring well locations in the Subbasin and their assigned aquifer designations (Shallow Zone, Deep Zone, Composite, or Unknown) based on well construction. Selected groundwater level hydrographs are presented for Shallow Zone wells in Figure 3-12a, for Deep and Composite Zone wells in Figure 3-12b, and all hydrographs are presented in Appendix 3d. Overall, water levels are stable for the periods of record. Figure 3-12a is a panel map with hydrographs from wells completed in the unconfined Shallow Zone. Shallow groundwater level information is concentrated in the Oakley, Brentwood, and Discovery Bay areas. These data indicate that basin-wide Shallow Zone water levels have remained fairly stable with no evidence of long-term declines. A minor shift in water level is seen in one well, 5 Binn in the southern portion of the Subbasin, that has dropped five feet over a 22-year period. This is not considered a significant factor to either groundwater quantity or quality in the Subbasin. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-29 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-30 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-31 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-32 Shallow Zone seasonal variations in groundwater levels on a regional basis are very minor (one to three feet). In the Oakley and Brentwood areas, a few Shallow Zone wells with deeper completions (100 to 150 ft bgs) show more variable seasonal trends (10 to 15 feet annual fluctuation in water levels) that suggest a slight increase in confinement (semi-confined) with depth. Shallow monitoring wells in the Discovery Bay area and eastward along Old River (BD-1, 2, 3) do not have pronounced seasonal water level changes (less than five feet annually) that may be attributed to influence by and proximity to the Delta. Shallow wells located in the western portion of the Subbasin (e.g., Well #11 [4.61-A], Appendix 3d) have more pronounced seasonal water level changes (about 10 feet annually) that is likely influenced by boundary effects due to proximity to the edge of the groundwater basin (e.g., the Diablo Range). The Delta Islands have a unique shallow groundwater situation unlike the rest of the Subbasin. Depth to water in subsided Delta islands (described in more detail below) is controlled by drainage ditches that convey irrigation water and seepage water from adjacent channels that is then pumped back into Delta channels. Deverel et al. (2016) reports that, due to this drainage system, groundwater levels are generally maintained at about 2-1/2 to 4 feet bgs in the Delta islands area. Figure 3-12b shows select hydrographs of the confined Deep and Composite Zone wells in the Subbasin. Regional large capacity supply wells target the Deep Zone and are generally over 200 feet in depth (LSCE, 2011). The hydrographs show generally stable conditions with seasonal water level fluctuation from 10 to 30 feet bgs with maximum decline during the summer months. This is followed by a full recovery of water levels during wet months (November to March). Some variation in annual peak water levels according to climatic trends is noted in the period between 2007 and 2010 and 2012 to 2015 when water levels appear to be affected by the state-wide droughts (Appendix 3d). There is no evidence of pumping- induced groundwater level declines. Vertical groundwater gradients can be monitored with nested monitoring wells. When plotted together, the water levels show the variation of groundwater levels in an unconfined, semi-confined and confined aquifer system (Figures 3-13a and b). The ECC Subbasin has three locations with nested monitoring wells: Stonecreek Monitoring Wells, Brentwood MW-14 Monitoring Wells, and Discovery Bay (Figure 3-13c). The Stonecreek Monitoring Well cluster has three monitoring wells screened between 100 and 350 ft bgs with a local shallow well (ECCID 5-33) that has a well depth of 11 ft bgs. Brentwood MW 14 has three wells screened between 114 and 315 ft bgs and a shallower well (BG-1) screened between 40-55 ft bgs. Discovery Bay MW4A has two wells screened between 122 and 347 ft bgs. All three nested wells show similar trends. In Stonecreek and Brentwood wells, the two deeper screened wells exhibit similar groundwater levels with seasonal variations of up to 30 ft. The shallower wells have higher groundwater levels with less seasonal variation (less than five feet for the ECCID 5-33 well). The Discovery Bay Deep Zone monitoring well (4AMW-357) has up to 60 feet seasonal variation and the Shallow Zone monitoring well (4AMW-152) has less than 5 feet of seasonal variation. These hydrographs demonstrate that groundwater levels in ECC Subbasin wells are stable and that groundwater conditions in the Subbasin are consistent with sustainable use. The water levels, by virtue of their consistent seasonal recoveries, also indicate that the Subbasin on the whole is full, with no room for additional groundwater recharge. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-33 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-34 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-35 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-36 Groundwater Elevation Contours Maps of groundwater elevation from 1958 to present indicate groundwater flow direction is from the Diablo foothills towards the Delta, generally from the southwest to the northeast in the central East Contra Costa Subbasin. Groundwater elevation contour maps developed by LSCE (1999) are available for selected years between 1958 to 1996 (Appendix 3e). These maps were developed with water level measurements for wells mostly constructed in the Shallow Zone and are representative of the unconfined aquifer. To evaluate recent groundwater level conditions in the Subbasin, groundwater elevation contour maps were prepared for Spring 2012 and 2018 for both the Shallow and Deep Zones (Figures 3-14a to Figure 3-14d). Shallow Zone The spring 1958 through spring 2018 groundwater contours for the Shallow Zone exhibit a similar pattern of flow, generally from the southwest to the northeast. In 1958, groundwater elevations ranged from about 55 feet msl in Brentwood to about 5 feet msl near the Delta north of Oakley; however, data is only available in the vicinity of Brentwood and Oakley. In spring 1991 additional data were available for the area south of Brentwood on the basin boundary where the groundwater elevation was as high as 75 ft msl to -15 ft msl around Discovery Bay. In spring 2012 (Figure 3-14a), the highest groundwater elevations were south of Brentwood at about 45 ft msl to a low of about -10 ft msl along Old River. In spring 2018 (Figure 3-14b) the Shallow Zone high groundwater elevations were again located south of Brentwood at about 40 ft msl to a low of about -5 ft in Discovery Bay. The general groundwater flow directions remained the same (to the northeast) and elevations north of Oakley were still around 5 ft msl. Deep Zone Contouring groundwater elevations in the Deep Zone is difficult due to the lack of well control exclusively in the Deep Zone. In contouring groundwater levels in the Deep Zone, water levels were used from wells with known construction in the Deep Zone and composite wells (constructed in both the Deep and Shallow Zones). The composite wells are identified by a different colored symbol on the contour maps and allow contours to tentatively be extended outward. Deep Zone groundwater level data is not available until 2007 around Oakley and 2012 around Brentwood and Discovery Bay. Given the limited data points and spatial representation, two Deep Zone groundwater contour maps were constructed: spring 2012 and spring 2018 (Figures 3-14c and d). In spring 2012, the highest Deep Zone groundwater elevations were about 50 ft msl south of Brentwood to a low of less than -20 feet msl around Discovery Bay. The spring 2018 Deep Zone contour map illustrates similar groundwater elevations to spring 2012 with high levels of 52 ft msl south of Brentwood, less than -20 ft msl in Discovery Bay, and about 2 ft msl north of Oakley. The Deep Zone groundwater flow direction is to the northeast which is similar to the Shallow Zone flow direction. Due to the limited spatial coverage of Deep Zone wells, evaluating groundwater flow and gradients within the Subbasin are challenging. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-37 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-38 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-39 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-40 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-41 Storage The total groundwater storage volume within the East Contra Costa Subbasin above the base of freshwater is estimated to be between 4.5 million AF (MAF) and 9.0 MAF based on the specific yield range of 5 to 10 percent and using spring 2018 groundwater level contours. DWR Bulletin 118 (2016 update), did not estimate total groundwater storage in the ECC Subbasin but did provide specific yield value ranges of 7 to 10 percent for the San Joaquin Subbasin and Delta for water bearing deposits. Table 3-1 summarizes calculations of total groundwater storage in the Subbasin using the 7 and 10 percent specific yield values and a lower value of 5 percent as a sensitivity for lower computed storage. An additional analysis is included in Table 3-1 (“To Base of Major Production Zone”) that estimates groundwater storage for the saturated thickness in the Subbasin from the regional water table (spring 2018) to the base of the major production zone (about 300 feet bgs). The total groundwater storage volume for this subsurface unit is estimated to be between 1.5 MAF and 3.0 MAF. There has not been a change in groundwater storage over time because groundwater levels between 1993 to 2019 have been stable. Sustainable yield3 refers to conditions under which extraction has not adversely impacted a variety of parameters including groundwater levels, storage, quality, etc. Historical conditions as reflected in the hydrographs and contour maps, where data is available, indicate that groundwater extraction has not impacted groundwater levels and storage and that the Subbasin is operating within its sustainable yield. Table 3-1. Estimates of Total Groundwater Storage (2018) Area ECC Subbasin Volume (acre-feet) Specific Yield (percent) Total Groundwater Storage (acre-feet) Notes on Specific Yield Basis To Base of Major Production Zone 30,254,373 5% 1,513,000 7% 2,118,000 Range of 7 to 10% for water bearing deposits DWR Bull. 118 (2003) Tracy Subbasin 10% 3,025,000 To Base of Freshwater 89,839,409 5% 4,493,000 7% 6,290,000 Range of 7 to 10% for water bearing deposits DWR Bull. 118 (2003) Tracy Subbasin 10% 8,986,000 Seawater Intrusion The East Contra Costa Subbasin has no coastline, is not bordered by the ocean, and direct seawater intrusion is not present. The Sacramento-San Joaquin River Delta has historically had brackish tidal water drawn in from the San Francisco Bay; however, levees installed around Delta islands to facilitate agriculture, and development of the Central Valley and State Water Projects, have altered the movement 3 “In general, the sustainable yield of a basin is the amount of groundwater that can be withdrawn annually without causing undesirable results. Sustainable yield is referenced in SGMA as part of the estimated basinwide water budget and as the outcome of avoiding undesirable results.” DWR, 2017. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-42 of tidal water through the Delta to maximize freshwater flow. A surface water salinity interface of two parts per thousand near Chipps Island west of the ECC Subbasin, is the State Water Resources Control Board adopted4 water quality objective to regulate Delta outflow. Though salinity in groundwater may occur naturally in parts of the Subbasin, it is not due to direct seawater intrusion into aquifers. The mechanism for seawater intrusion is illustrated in Figure 3-15. When a direct connection exists such as along the coast, seawater may be drawn into aquifers when the gradient for freshwater outflow is reduced or reversed due to over-pumping. This causes the saltwater/freshwater aquifer interface to move inland. As mentioned above, this is not present in the ECC Subbasin. Figure 3-15 The Process of Saltwater Intrusion from an Aquifer Source: https://www.usgs.gov/media/images/process-saltwater-intrusion In the Bay-Delta setting of the ECC Subbasin, there is no saltwater interface in the subsurface and the aquifers are freshwater. A potential source of saline water intrusion might be migration of baywater into the Shallow Zone aquifers. While fresh baywater outflow through the Delta is managed, increases in baywater salinity could potentially occur due to sea-level rise. This occurrence may potentially impact sustainability if intruded shallow groundwater migrated vertically downward into the Deep Zone aquifers used for water supply. This mechanism is illustrated by two cross-sections (A-A’ and C-C’) from the 1999 LSCE report (Figure 3-16a, b, c). Figures 3-16b and 3-16c show the potential for interactions through hydraulic pathways between stream and delta channels and shallow aquifers. Figure 3-16b shows 4 https://www.baydeltalive.com/maps/11634 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-43 substantial clay layers that impede vertical migration to the Deep Zone. Connection to the Deep Zone may be of concern for some areas where domestic and agricultural pumping occurs. One possible area is depicted on Section C-C’ (Figure 3-16c) where there are fewer hydraulic clay barriers present. Figure 3-16d presents the average chloride concentrations measured in the Shallow Zone and Deep Zone wells over the last ten years. Chloride concentrations are below 500 mg/L and are generally around the 250 mg/L Recommended MCL with a few isolated exceptions. Seawater Intrusion (or baywater in the ECC Subbasin) will be evaluated with chloride concentration maps that include the new dedicated Shallow Zone monitoring wells (see Section 6.2.4 for monitoring well list and well map). These wells will act as sentinels for intrusion-related degradation of water quality. There is currently no chloride concentration contour since the monitoring wells have not been installed. A chloride concentration map will be produced for the initial annual report and then for each 5-year update unless more frequent reporting is warranted through analysis of test results. Based on initial sampling and an assessment of basin-wide Shallow Zone water quality characteristics, a baseline for intrusion will be determined. A threshold is set at 250 mg/L, which is the Recommended Limit Secondary Maximum Contaminant Level (SMCL) for chloride as defined by the EPA and below which are the majority of chloride concentration is in the Subbasin. Figure 3-16a Partial Cross Section Location EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-44 Figure 3-16b Partial of Cross Section A-A’-Clay Barriers Prevent Vertical Baywater Migration Figure 3-16c Partial Cross Section C-C’: Potential for High Salinity Baywater Migration Clay lithologies provide hydraulic barriers to vertical migration Freshwater Big Break: potential high salinity baywater EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-45 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-46 Groundwater Quality Groundwater quality in the Subbasin is characterized for this section through a variety of tables, maps and graphs. The entire water quality data set is provided in Appendix 3f. Key groundwater quality constituents discussed below include total dissolved solids (TDS), nitrate, chloride, arsenic, boron, and mercury. These constituents were selected because they have the potential to influence sustainability (as opposed to localized, or site-specific contamination). A concern for domestic water supply, including individual domestic wells and large public water systems serving municipalities, is groundwater hardness. This concern is included as a sustainability issue in Section 7 Sustainable Management Criteria. Monitoring and reporting on trends in hardness of well water are also discussed in Section 6 Monitoring Network and Data Management System. Maps of average and maximum concentration for the selected constituents are displayed in Figures 3-17a and b through 3-20a and b. Recent data (after 2014) are lacking for some constituents so concentrations for wells with results prior to 2014 are included on the map with a smaller symbol. Time series graphs for these same constituents are presented in Appendix 3g and can be used to evaluate trends over time (e.g., TDS or chloride increasing or decreasing over time). In general, groundwater quality meets most water quality objectives and serves a variety of domestic and agricultural uses throughout the Subbasin. However, minor restrictions (discussed in more detail below) are caused by naturally occurring salinity levels that are elevated basin wide and nitrate levels that are slightly elevated in the shallow zone (less than 150 ft bgs). Water quality concentrations in wells are compared for some constituents (nitrate as nitrate, arsenic, and mercury) to the California State Water Quality Control Board (SWQCB) drinking water standards called maximum contaminant levels (MCLs). Not all constituents (e.g., TDS and chloride) have an MCL and are compared to the secondary MCLs (SMCLs) that address esthetics such as taste and odor. Total Dissolved Solids TDS is a general measure of salinity and overall water quality. Salinity of groundwater may increase as influenced by land use or may be naturally sourced where subsurface geologic materials are derived from marine sediments. Figures 3-17a and b illustrate the average and maximum TDS concentrations for Shallow, Deep, and Composite Zones and for wells where the zone is unknown. TDS varies widely across the Subbasin, although it is characteristically high, ranging between 500 and 1,500 mg/L, in all areas. The Secondary maximum contaminant level (SMCL) for TDS is 500 mg/L (Recommended), 1,000 mg/l (Upper Limit), and 1,500 (Short-Term Limit). The SMCL is established for aesthetic reasons such as taste and odor and is not based on public health concerns. In the Shallow Zone, only three wells in Brentwood have recent results (since 2014) with TDS concentrations ranging between 500 and over 1,500 mg/L and older data indicate similar values. The lack of data for Shallow Zone wells is noted as a data gap. A lower portion of the Shallow Zone (between 80 and 140 ft bgs) in the vicinity of Discovery Bay contains brackish to saline water with EC levels between 2,000 and 6,500 uS/cm (Wells 1B, 4A, and 7, spring 2013). To prevent cross contamination of aquifer units, production wells are constructed with a deep cement seal below 140 ft bgs. The Deep Zone has many wells with TDS concentrations between 500 and 1,000 mg/L. The Deep Zone Discovery Bay wells have TDS concentrations generally below 600 mg/L and three City of Brentwood wells (wells 6, 7, and 8) increased from 600 mg/L and have stabilized with TDS concentrations around 1,000 mg/L (the upper secondary MCL) (Appendix 3g). The areas around Antioch and Byron have elevated TDS concentrations compared to the rest of the Subbasin, with some average results over 2,000 mg/L. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 -BASIN SETTING LSCE 3-47 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 -BASIN SETTING LSCE 3-48 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 -BASIN SETTING LSCE 3-49 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 -BASIN SETTING LSCE 3-50 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 -BASIN SETTING LSCE 3-51 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 -BASIN SETTING LSCE 3-52 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 -BASIN SETTING LSCE 3-53 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 -BASIN SETTING LSCE 3-54 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-55 In summary, TDS concentrations in groundwater in the Subbasin exceed or are near the recommended SMCL (500 mg/L) in most wells (Table 3-2) suggesting that water concentrations are naturally higher for TDS (LSCE 1999). Table 3-2. Water Quality Concentrations for Key Constituents Constituent (Units) Date Range Number of Wells No. of Measurements Concentration DDW DWR Geo-tracker USGS Total Range Median Average St Dev TDS (mg/L) 1957- 2019 87 46 73 22 228 802 86 - 20,400 885 1,098 1,431 Chloride (mg/L) 1957- 2019 97 67 80 36 280 1562 11 - 4,900 168 231 310 NO3-N (mg/L) 1957- 2019 135 23 125 30 313 2360 ND - 1,400 0.5 4.7 30.5 Arsenic (ug/L) 1957- 2019 88 12 81 9 190 959 ND - 750 3 8 29 Chloride Chloride is also a common way to indicate salinity. Figures 3-18a and b illustrate the average and maximum chloride results for the Shallow, Deep, and Composite Zones and the wells where the zone is unknown. Where zones are known, chloride concentrations generally decrease with depth to under 200 mg/L. Shallow Zone wells have higher chloride concentrations in the vicinity of Brentwood (230 to 280 mg/L) and Discovery Bay (360 to 2,000 mg/L) than the Deep Zone wells. Deep Zone wells (Wells 6, 7, and 8) in Brentwood have increased from less than 100 mg/L to over 200 mg/L) and Discovery Bay wells are stable and generally <100 mg/L. All results in the two zones (Shallow and Deep) are generally under 500 mg/. The areas around Antioch and Byron have elevated chloride concentrations compared to the rest of the Subbasin, with average results up to over 1,800 mg/L. The SMCL for chloride is 250 mg/L (Recommended), 500 mg/L (Upper Limit), and 600 mg/L (Short-Term). In summary, chloride concentrations in groundwater in the Subbasin exceed or are near the recommended SMCL for chloride (250 mg/l) in most wells (Table 3-2) suggesting that water concentrations are naturally higher for chloride (LSCE 1999). Nitrate Nitrate is both naturally occurring and can be a result of human activity (e.g., fertilizers, septic systems, and animal waste). The MCL for nitrate as nitrogen (N) is 10 mg/L for drinking water. Figures 3-19a and b illustrate the average and maximum nitrate concentrations as N for the Shallow, Deep, and Composite Zones and for wells with an unknown aquifer zone. Wells with average nitrate as N concentrations that exceed the MCL are Shallow Zone wells in the Brentwood area (24 to 121 mg/L) and Unknown Zone wells scattered in the central western portion of the Subbasin. A few City of Brentwood composite production wells have been taken out of service due to high nitrate concentrations. In previous work, the higher Shallow Zone concentrations have been attributed to agricultural influences in the area and lack of confining clay units between soil horizons and shallow aquifer materials. Continued monitoring of EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-56 Brentwood Deep Zone wells (currently all below 10 mg/L) will monitor whether nitrate is migrating from the Shallow Zone. Deep Zone production wells in the Discovery Bay and Oakley area have nitrate concentrations less than 2 mg/L. Wells in the Delta Island area in the northern and eastern portion of the Subbasin generally have very low nitrate as N concentrations. In summary, nitrate is observed in some Shallow Zone areas of the Subbasin (i.e., Brentwood), with concentrations exceeding the MCL (10 mg/L) that may be linked to historical agricultural influences in the area. Arsenic Arsenic is a naturally occurring constituent and is commonly found in groundwater throughout California. An MCL was established at 10 ug/L in California in 2008. Figures 3-20a and b illustrate the average and maximum arsenic concentrations for the Shallow, Deep, and Composite Zones and the wells where the zone is unknown. For wells in the Shallow and Deep Zones, all have average and maximum arsenic concentrations at or below 10 µg/L with four exceptions: Knightsen, two public water systems on Sandmound Blvd., and Bethel Island. Near Discovery Bay, there have been detections of 10 µg/L; but, on average, the Discovery Bay area has concentrations less than 8 µg/L. For Unknown Zones, most of the wells are less than 8 µg/L. An exception is in the Antioch area which has higher concentrations of arsenic with average results over 100 µg/L. In summary, arsenic concentrations are less than the MCL (10 ug/L) basin wide. Boron Boron is a naturally occurring constituent in groundwater and particularly in Contra Costa County 5. The most common sources of boron in drinking water are from leaching of rocks and soils, wastewater, and fertilizers/pesticides. Boron concentrations in the Subbasin range from 500 ug/L to over 4,000 ug/L with the majority over 1,000 (Appendix 3f). MCLs for boron have not been established but there is an agricultural goal (700 ug/L) where some crops may become sensitive, a state notification level (SNL)l6 (1,000 ug/L), and a US EPA Health Advisory for non-cancer health effect (5,000 ug/L). Boron concentrations in groundwater in the Subbasin exceed the agricultural and SNL (1,000 ug/L) in most wells but are less than the EPA Health Advisory (5,000 ug/L) suggesting that water concentrations are naturally higher. Mercury Marsh Creek runs from Mt. Diablo through Brentwood and out to the San Joaquin River and drains water from the Mt. Diablo Mercury Mine operated from 1849 to 1971. There is potential for rainwater to leach mercury from mine tailings and to flow into the Marsh Creek watershed. However, there is no evidence that mercury has contaminated groundwater in the Subbasin and no wells in the ECC Subbasin tested for mercury have exceeded the MCL (2 ug/L). 5 The SWQCB Division of Water Quality GAMA Program “Groundwater Information Sheet for Boron (B), revised November 2017. Contra Costa County was identified on one of the top three counties in the state for boron detection from a study of public water supply wells from 2007 to 2017. 6 Notification levels are non-regulatory health-based advisory levels establish by the SWRCB for chemicals with not established MCL. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-57 Appendix 3f is a table of all groundwater quality (general minerals and trace elements) in the Subbasin, by zone. Most of the wells in the Subbasin are missing construction information so water quality for the Shallow and Deep Zones is limited. In summary, groundwater in the Subbasin generally exceeds or is near the recommended SMCL for TDS (500 mg/L) and chloride (250 mg/l) (Table 3-2). The observed concentrations may reflect a naturally higher baseline for these constituents (LSCE 1999). Nitrate is observed in some Shallow Zone areas (i.e., Brentwood) in the Subbasin, with concentrations generally exceeding the MCL (10 mg/L) that may be linked to past agricultural influences in the area. Arsenic concentrations are generally less than the MCL (10 ug/L) basin wide. Boron concentrations are high in most wells and are attributed to a naturally elevated baseline. Groundwater serves a variety of domestic and agricultural uses throughout the Subbasin with limited restrictions due to natural (salinity and boron) and anthropogenic (nitrate) causes. The availability of surface water gives the opportunity to mitigate these issues when necessary. Depending on local groundwater quality, the stringent municipal standards for drinking water are met by a mix of water sources: City of Antioch uses surface water only, DWD and Brentwood blend groundwater with surface water, and TODB uses groundwater only. The ECC Subbasin’s groundwater quality is generally stable which indicates that groundwater extraction is not degrading water quality and the Subbasin is being operated within its sustainable yield. Groundwater Contamination Risk There are numerous potential anthropogenic sources of groundwater contamination in the ECC Subbasin. Almost any human related activity involving hazardous substances and waste has the potential to contaminate groundwater. Some activities may lead to groundwater contamination by first contacting soil and then seeping to groundwater. In the ECC Subbasin, the depth to groundwater may occur within a few feet of the ground surface thus increasing the risk that soil contamination may reach a shallow aquifer. Other sources may involve more direct contact between groundwater and hazardous substances such as associated with hydrocarbon transmission lines or leaky storage tanks at retail gasoline stations. Historical and current industrial activity in the east Contra Costa region is also a source of past and potential future groundwater contamination. In Oakley, shallow groundwater and soil contamination occurred at a former Dupont plant that manufactured a gasoline agent, refrigeration cooling compounds, and additives for household products and food. That site operated from 1956 to 1998 and, in 2015, remedial obligations were transferred to Chemours, a subsidiary of Dupont. Chemours worked with the Department of Toxic Substances Control (DTSC) to remediate the site and ultimately returning most of it to a new commercial use now underway7. Another potential source of groundwater contamination is the historical and current oil and gas activity in the area. Although areas of current and future activity may be more restrictive in areas of urban growth, it is expected that continued development and redevelopment of oil and gas fields may occur in rural and unincorporated areas of the subbasin. In the ECC Subbasin, oil and gas wells would penetrate the Shallow and Deep Zone freshwater aquifers that are a source of supply for domestic, agricultural, industrial, and environmental uses. Pathways for contamination via these wells would be present and may be of concern 7 https://eastcountytoday.net/oakley-officially-breaks-ground-on-new-logistics-center-could-create-2800-jobs/ EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-58 to GSAs seeking to protect water quality and maintain long-term sustainability of groundwater resources in the subbasin. The following sections provide an overview of these anthropogenic sources of potential concern to groundwater quality. Although, SGMA does not transfer oversight of regulation of hazardous substances to GSAs, the agencies may seek to mitigate risks by informing the applicable regulatory agency of the intersection between contamination sources and mechanisms by which degradation may occur in the unique hydrogeologic setting of the ECC Subbasin. Section 8 discusses a potential policy for GSA engagement with agencies responsible for mitigating and remediating hazardous waste that may reach groundwater. Groundwater Contamination Sites Figures 3-21a and 3-21b illustrate the open and closed groundwater contamination sites in the ECC Subbasin. Contaminated sites can pose a hazard to human health through the contamination of aquifers if the area is using groundwater. Contamination site data were taken from Geotracker 8 and are divided into cleanup program sites, leaky underground storage tank (LUST) sites, and land disposal sites. Appendix 3h lists the 35 open sites and 105 closed sites including the potential contaminants of concern for each site. The majority of sites are in Antioch and Brentwood and the most common contaminant is hydrocarbon. Oil and Gas Wells Oil and gas wells are regulated and permitted through the state Department of Conservation, Geologic Energy Management Division (CalGEM). In east Contra Costa County, there are as many as eleven oil and gas fields either wholly or partially within the ECC Subbasin which target oil and/or gas sands at several thousand feet below ground surface. Produced water in these sands is saline based on interpretation of electric geophysical logs performed in open boreholes prior to well installation. As with all oil and gas wells in the subbasin, CalGEM regulations require a separate surface casing to be installed below the base of freshwater 9. In Brentwood, for example, surface casings extend to 1,750 feet. This depth is consistent with the basin conceptualization presented in this GSP. Even though the interpreted base of freshwater is as deep as 1,750 feet, most groundwater production in the ECC Subbasin is shallower than 500 feet. The legacy of oil and gas activity in the ECC Subbasin is the presence of up to several hundred abandoned and plugged wells. The abandonment programs are regulated through CalGEM requiring cement plugs at various depths to ensure that fluids in the oil zone (oil, gas and connate water) do not migrate upward into freshwater aquifers. Appendix 3i contains figures showing oil and gas fields and wells located in the ECC Subbasin as obtained from CalGEM’s online well finder tool 10. Production records are also available online through CalGEM 11. 8 Geotracker is the state Water Board’s online resource to track data from waste discharges to land and includes unauthorized releases of hazardous substances from underground tanks: https://geotracker.waterboards.ca.gov/. 9 https://www.conservation.ca.gov/calgem/Pages/Oil,-Gas,-and-Geothermal-Rulemaking-and-Laws.aspx 10 https://www.conservation.ca.gov/calgem/Pages/WellFinder.aspx 11 https://filerequest.conservation.ca.gov/?q=production_injection_data EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-59 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-60 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-61 Land Subsidence There are no historical records of impacts from subsidence due to groundwater withdrawal in the ECC Subbasin. Land subsidence in the Subbasin is continuously monitored by the Plate Boundary Observatory (PBO) monitoring network managed by University NAVSTAR Consortium (UNVACO). The PBO’s main task is to “quantify three-dimensional deformation and its temporal variability across the active boundary zone between the Pacific and North American plates.” The PBO stations can be used to monitor for land subsidence using vertical land surface measurements. PBO stations are used to measure centimeter to millimeter-scale movement on the Earth’s surface. Four stations located in or near the Subbasin (Figure 3-22) all show minor displacements. PBO stations take measurement once per day, to mitigate erroneous data a 30-day rolling average was applied to the data. PBO Station 256 (P256), located inside the Subbasin, has shown a vertical displacement from 2005 to 2019 of -0.01096 inches per year. PBO Station 230 (P230) west in the Diablo Mountains also has a slight downward displacement of -0.01461 inches per year. Two stations near Antioch and Tracy (P248 and P257) have a slight upward displacement of the land surface. Table 3-3 below provides the estimated rate of land surface change. Trends do not indicate inelastic downward displacement in the land surface. Table 3-3. Land Surface Displacement Rates at PBO Sites Monitoring Location Location Relative to Subbasin Period of Record Rate of Land Surface Displacement (inches per year) Rate of Land Surface Displacement (feet per year) Inside East Contra Costa Subbasin P256 East of Center of Subbasin 2005-2019 -0.0093 -0.00077 Outside East Contra Costa Subbasin P230 Southwest of Subbasin 2005-2019 -0.01487 -0.00124 P248 Northwest of Subbasin 2007-2019 .01092 0.00091 P257 Southeast of Subbasin 2006-2019 .001461 0.00122 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-62 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-63 DWR has also published Interferometric Synthetic Aperture Radar (InSAR) results in partnership with the European Space Agency’s Sentinel-1A satellite with the data processed by TRE ALTAMIRA 12. These data present measurements of vertical ground surface displacement between two different dates. InSAR mapping of land surface elevation is particularly useful for complementing high spatial and temporal resolution data at CGPS station locations with observations of land subsidence over a large area for highlighting locations where change is occurring. Throughout most of the Subbasin there has been minimal vertical changes between June 2015 and June 2019 (Figure 3-22), vertical measurement accuracy is reported to be about 18 millimeters (0.7in) (DWR 2021). Vertical displacement during this time period was mostly stable, no change to slightly downward with most values ranging from -0.5in to 0.25in in the western portion of the Subbasin. The Delta area (northern and eastern portion of the Subbasin) shows higher vertical displacement that is due to a mechanism that is described below (hydrocompaction). The InSAR data in the vicinity of P256 has a similar vertical displacement (about 0.4in) as observed at P256 during the June 2015 to June 2019 time period. In the late 1800s to the early 1900s levees were built along stream channels in the delta and the rich land was converted to agriculture (discussed in more detail in Section 2.1). However, this caused ongoing land subsidence associated with drainage for agriculture, called hydrocompaction, on islands in the Delta including parts of the ECC Subbasin specifically. Hydrocompaction is due to dewatering of peat soil that dries out and compresses 13 as a result of land reclamation. This caused many central Delta islands to drop 10 to nearly 25 feet below sea level (USGS, 1999, Figure 3-23a). The Delta soils are composed of 1) coarser sediments concentrated near the natural waterways of the Delta and 2) peat from decaying marsh vegetation concentrated near the centers of the islands (up to 60 feet thick in the western Delta). Figure 3-23b illustrates the late 1880’s freshwater tidal marsh land surface profile (upper diagram) and the current configuration of many islands (lower diagram) that is saucer-shaped due to compacted peat soils in the interior and mineral sediments at their edge. Currently, groundwater levels are maintained on the islands by a network of drains at three to six feet bgs with drainage water pumped back into the stream channels (Figure 3-23b). Though this GSP is only required to discuss subsidence due to groundwater withdrawal, understanding of how these Delta islands are constructed improves understanding of interactions between surface water and groundwater in the Delta area. 12 https://gis.water.ca.gov/arcgisimg/rest/services/SAR 13 Source: Water Education Foundation, 2020. Can Carbon Credits Save Sacramento-San Joaquin Delta Islands and Protect California’s Vital Water Hub? Gary Pitzer, February 27, 2020. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-64 Figure 3-23a. Subsidence on Delta Islands (source: https://www.usgs.gov/centers/ca-water-ls/science/subsidence-sacramento-san-joaquin-delta?qt- science_center_objects=0#qt-science_center_objects) EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-65 Figure 3-23b. Cross-section of Subsidence and Drains on Delta Island. Source: Mount and Twiss (2005) Interconnected Surface Water Systems Interconnected surface water systems are the locations where groundwater and surface water are hydrologically connected. It is important to know where these systems are located in order to minimize impacts of groundwater pumping on the surface water bodies and biological communities that rely on the interconnected water system. The ECC Subbasin is bounded by the San Joaquin River to the north and Old River to the east with an extensive network of canals installed (Figure 3-10). Delta islands located in the northern and eastern portion of the Subbasin, as described above, are protected by levees and require excess water that collects in subsurface drains to be discharged to the Delta. Figure 3-24 identifies the surface water features in the Subbasin and vicinity and illustrates coverage of subsurface tile drains installed at between 5 and 814 feet bgs to provide drainage of water to the river. Given this unusual configuration, Old River and the San Joaquin River are considered interconnected rivers and currently or historically, surface water depletions have not occurred along these rivers. In the western portion of the Subbasin a few creeks are present that are considered a natural source of recharge to the Subbasin (Figure 3-24) and have the potential to be considered interconnected systems. Marsh Creek, the most prominent, is earthen lined and channelized, and is adjacent to both the City of Brentwood and DWD pumping wells. The Marsh Creek dam passively drains all flows that enter it until the level subsides to the primary spillway level. It may be vulnerable to impacts from the loss of interconnected surface water due to groundwater pumping and groundwater level declines. Currently there is an incomplete understanding of the ECC Subbasin surface water/groundwater connection, but this is expected to be remedied through installation of multiple completion monitoring wells and future monitoring efforts related to this GSP. 14 As communicated by individual water districts. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-66 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-67 Figure 3-25a is a map illustrating the spring 2018 depth to shallow groundwater in the ECC Subbasin. There is not complete coverage of the Subbasin, but it does present the 30 ft depth to water contour that may represent the point when a stream is no longer considered interconnected to groundwater. Review of the depth to water figure indicates that the majority of the Subbasin may have interconnected surface water and groundwater. Specifically, the San Joaquin River, Old River, and portions of western creeks are likely connected to the groundwater system and there is then potential for regional groundwater pumping to impact groundwater dependent ecosystems (GDEs). Figure 3-25b shows the natural and artificial channels in the Subbasin with the most conservative estimates of potential for interconnectivity using 2018 shallow DTW created from subtracting the digital elevation model from groundwater elevation contours. Most of the natural channels in the Subbasin are located in the west of the Subbasin. Marsh Creek however starts to become likely connected with groundwater in Brentwood. Many artificial channels in the eastern part of the Subbasin may exhibit interconnectedness with groundwater as they are commonly located in areas where DTW is less than 10 feet. Groundwater Dependent Ecosystems Groundwater dependent ecosystems (GDEs) “refers to ecological communities or species that depend on groundwater emerging from aquifers or on groundwater occurring near the ground surface” outlined in the GSP Emergency Regulations. Each plan is required to identify groundwater dependent ecosystems within the basin, utilizing data available from DWR or the best available information. GSAs are only responsible for impacts to GDEs resulting from changing groundwater conditions resulting from pumping or groundwater management in the Subbasin (TNC, 2019). For example, if groundwater conditions stay the same but GDEs lose access to water due to surface water diversions/depletions, this is not the GSA’s responsibility. GDEs are similarly defined as “the plants, animals, and natural communities that rely on groundwater to sustain all or a portion of their water needs” by The Nature Conservancy (TNC) in the Guidance for preparing Groundwater Sustainability Plans (Rohde et al, 2018). GDEs are an important aspect of the diverse California landscape and are found in nearly all subbasins. The GDEs are diminishing rapidly and largely due to human interference and unsustainable groundwater extraction (Rohde et al, 2018). Water Code Section 10723.2 requires the GSP to identify GDEs and determine how groundwater does or does not affect them. The following section describes the process for identifying the GDEs within the ECC Subbasin and mapping their location. The Natural Communities Commonly Associated with Groundwater (NCCAG) Dataset was used as a starting point to identify GDEs within the Subbasin. This dataset is compiled from 48 publicly available agencies datasets and was then reviewed by a working group comprised of DWR, TNC, and the California Fish and Wildlife (Figures 3-26a and b). The Subbasin GDEs exhibited in Figures 3-26a and b were compared by the county with local information, and it was concluded that these are the best available data. Further analysis of GDEs in ECC was conducted by identifying areas where depth to groundwater is greater than 30 feet, the general vegetation maximum rooting depth. The assumption was that those areas could be eliminated however, groundwater level monitoring is lacking in some of the western areas of the Subbasin so no changes to Wetland or Vegetation NCCAG Datasets were made. Current land use was also analyzed to determine if the parcel was still a GDE. Using DWR’s 2016 Land use data set it was found that 67 acres of vegetation and 18 acres of wetland were no longer classified as native materials and the corresponding GDEs were removed. A total of 13,970 potential GDE acres (11,985 wetlands and 4,304 vegetation with some areas of overlap in the ECC Subbasin) were identified by the NCCAG database and retained for this GSP. Most of these areas are located in the Delta with a EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-68 few occurring along western creeks. Table 3-4 includes all species in the ECC Subbasin as identified by TNC. TNC has identified 22 vegetation species and additional category of Not Applicable. The majority of species represent a small percentage of the total GDEs; the largest designation is Not Applicable. Figure 3-27 identifies critical habitat for species in the ECC Subbasin: Steelhead (threatened), Delta smelt (threatened), and vernal pool fairy shrimp (threatened). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-69 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-70 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-71 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-72 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-73 Table 3-4 Vegetation Species in Subbasin Dominate Species Percentage of Total Vegetation Dominant Species Percentage of Total Vegetation Arctic Rush < 1% Iodine Bush 4% Arroyo Willow 9% Narrowleaf Cattail < 1% Broadleaf Cattail 1% Narrowleaf Willow 2% Broadleaf Pepper-grass 4% Northern California Black Walnut < 1% California Bulrush 7% Not applicable 37% California Rose < 1% Red Willow 0% Common Reed 1% Shrubby Seepweed 1% Fremont Cottonwood 1% Three-square Bulrush < 1% Giant Reed < 1% Tree-of-Heaven < 1% Goodding's Willow 10% Valley Oak < 1% Hardstem Bulrush 16% White Alder < 1% Himalayan blackberry 5% -- -- The Subbasin has multiple GDE areas, mostly in the Delta in the north along the San Joaquin River and the east along the Old River in addition to various canals located in the east. However, these areas have minimum groundwater pumping from mostly domestic wells (Figure 2-3a). TODB is wholly reliant on groundwater and has GDEs noted around the town; a shallow zone groundwater monitoring well has been identified as a Data Gap and will be installed as part of this GSP. Brentwood also uses groundwater but no GDEs are noted in the area; however, three shallow zone monitoring wells are part of the monitoring network. Bethel Island has a groundwater production well that is located near GDEs for both wetlands and vegetation, and this also has been identified as a Shallow Zone monitoring well Data Gap. The southern portion of the Subbasin has small areas of GDEs but with no municipal groundwater production; however, this area is also identified as a Shallow Zone monitoring well Data Gap for this GSP. New projects that include construction of wetlands are in the planning and/or constructions phase and will be added to the GDE maps when completed. They include Dutch Slough Tidal Restoration Project 15 located at the intersection of Marsh Creek and the Delta (managed marsh and tidal), Three Creeks Parkway Project 16 located in Brentwood, and Franks Track State Park 17. Municipal Water District of Southern California (MWD) owns all or parts of two islands 18 in the Delta area of the ECC Subbasin: 15 Information can be access here: https://water.ca.gov/Programs/Integrated-Regional-Water-Management/Delta- Ecosystem-Enhancement-Program/Dutch-Slough-Tidal-Restoration-Project. Construction to restore 1,200 acres launched in 2018, planting occurred in 2020 and a levee breach is planned for 2021. 16 Information can be accessed here: https://www.contracosta.ca.gov/5814/Three-Creeks-Parkway-Project 17 Information can be accessed on Franks Tract Futures here: https://franks-tract-futures-ucdavis.hub.arcgis.com/ 18 Holland and Webb Tracts are owned by Municipal Water District (MWD) that are part of the proposed water storage project call Delta Wetlands Project. Information can be accessed here: EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-74 Webb Tract (100% MWD owned) and Holland Tract (75% MWD owned). Originally Webb Tract was slated to be a Reservoir Island to store available water in winter and discharged in summer or fall and 845 acres of Holland Tract was to be wetlands and a dedicated Habitat Island. However, as of September 2020 the islands are projected to continue as farms for at least the next 5 years with no major land use change and MWD is reportedly not pursuing the island storage project 19. Future updates to the GSP will include refinement of GDE locations in the Subbasin as land use changes. Evaluation of GDE Health The GDE Pulse dataset, developed by TNC, was also reviewed and evaluated for the Subbasin (Klausmeyer et al., 2019) in relation to GDEs. The GDE Pulse dataset utilizes remote sensing data from Landsat satellites to monitor the health of GDEs by observing how moisture and greenness change over time (Klausmeyer et al., 2019). The most common way to assess the health of the GDEs using remote sensing data is through the Normalized Derived Vegetation Index (NDVI). NDVI is calculated as follows: 𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁=𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑁𝑁𝐼𝐼𝐼𝐼𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝐼𝐼−𝑁𝑁𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑁𝑁 𝑅𝑅𝑁𝑁𝐼𝐼 𝐿𝐿𝑉𝑉𝐿𝐿ℎ𝑡𝑡𝑁𝑁𝑁𝑁𝑁𝑁𝑁𝑁 𝑁𝑁𝐼𝐼𝐼𝐼𝑁𝑁𝑁𝑁𝑁𝑁𝐼𝐼+𝑁𝑁𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑁𝑁 𝑅𝑅𝑁𝑁𝐼𝐼 𝐿𝐿𝑉𝑉𝐿𝐿ℎ𝑡𝑡 Calculated NDVI values less than zero indicate unhealthy or dead vegetation, values between zero and 0.1 are most likely barren, values of 0.2 to 0.3 are considered moderate vegetation, and values above 0.6 are very dense and green vegetation (Weier and Herring, 2000). TNC merged the NCCAG and remote sensing datasets together and removed background noises such as clouds and calculated the NDVI yearly average values. According to Klausmeyer et al. (2019), yearly average NDVI values between July 9 to September 7 represent readings during the typically dry months when GDEs would be dependent on groundwater. The yearly average was calculated by finding the medoid, which is “a multi-dimensional feature space median” (Klausmeyer et al., 2019). Figure 3-28a through Figure 3-28e illustrates the NDVI changes in the Subbasin for 1997, 2004, 2010, 2015, and 2018. The five years selected show the likely GDEs identified in the Subbasin under a variety of water year conditions ranging from wet (1997, during and after several wet years), dry (2004, during and after several dry years), more moderate (2010, above normal after a dry year; 2018, below normal after a very wet year), and critically dry (2015, during and after two critical years). For evaluating the GDE health in the Subbasin over the last 20 years, NDVI values greater than 0.2 were interpreted to be healthy, based on guidance from Weier and Herring (2000), and values less than 0.2 were interpreted to be unhealthy. The NDVI changes throughout the Subbasin have occurred through many different water year types. NDVI data changed the most in Clifton Court Forebay and the Delta region of the Subbasin. Throughout time the GDE health has changed in several areas of the Subbasin particularly in Franks Tract, but in general GDE health poorer historically compared to recent years. In the earlier periods, larger areas had values of less than 0.2 while, in the more recent surveys (2015 and 2018), the overall health of the vegetation is greater than 0.2. NDVI data along Franks Tract and Clifton Court Forebay appear to be consistently below 0.2; however, in some instances, the values rise 0.2, but other factors could be contributing to this phenomenon. The values of less than 0.2 can be due to the NCCAG https://www.spk.usace.army.mil/Portals/12/documents/regulatory/eis/190109804-eis/190109804- SDEIS/AppendixJ.pdf 19 Delta Protection Commission meeting, September 17, 2020, report by Stephen Arakawa, MWD, on Delta Islands. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-75 vegetation dataset, which is based on more current conditions and historically vegetation may not have always been present in these areas. The evaluation of NDVI data suggest that the overall GDE health within the Subbasin has experienced changes but generally remained stable between 1997 and 2018. The greatest periods of stress to GDE communities appears to have occurred during the earliest and later part of the 1997-2018 period, in 1997 and 2018. This could be explained by changes geography in the area, what was historically water channels could presently have vegetation or be considered a wetland. Very few areas of stressed GDE health are evident in 2015, when the groundwater conditions in the Subbasin were at historically low levels because of drought conditions, compared to the moderate 2018 conditions. Figure 3-28f and Figure 3-28g shows the NDVI changes throughout the available record (1985-2018) for likely GDE areas along Big Break and Marsh Creek. The NDVI data for communities along Big Break shows a gradual increase in GDE health with the average plotting above 0.2 for the entire record, only a small portion of GDEs plotted below 0.2 in the early part of the record. In Marsh Creek there are limited GDEs identified, and the health has been stable throughout time. These data suggest that overall health of the GDE communities along Big Break and Marsh Creek are healthy with majority of NDVI values above 0.2 and a long-term upward trend (Big Break) and stable healthy conditions (Marsh Creek), suggestive of general improving or stable health conditions between 1985 and 2018. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-76 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-77 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-78 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-79 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-80 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-81 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-82 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-83 3.4 Summary Basin Setting • ECC Subbasin is bounded on the north, east, and south by the Contra Costa County line, which is contiguous with the San Joaquin River (north) and Old River (east). In the west, the Subbasin is bounded by marine sediments of the Coast Range. • Topography and geological formations gently slope to the northwest. The upper 400 feet of Subbasin sediments is comprised of alluvial deposits with discontinuous clay layers interspersed with more permeable coarse-grained units. • The ECC Subbasin aquifer system is divided into the upper unconfined Shallow Zone (to about 150 ft bgs) and a lower semi-confined to confined Deep Zone (the Corcoran Clay is not present in the Subbasin). Most water wells are constructed within the upper 400 feet. Groundwater Conditions • Groundwater levels in the ECC Subbasin are stable which indicates that the Subbasin is being operated within its sustainable yield. This is due to surface water being the major supply source for agricultural and urban uses. Groundwater flow direction is generally from the southwest to the northeast toward the Delta. • Groundwater quality is generally good with no restrictions for agricultural or urban uses in the Subbasin. Constituents of concern are TDS, chloride, nitrate as N, and boron which all have natural sources with the exception of nitrate. TDS concentrations in both the Shallow Zone and Deep Zone are generally stable and average 1,100 mg/L, around the SMCL of 1,000 mg/L. Chloride is another indicator of salinity and averages around 230 mg/L which is near the SMCL of 250 mg/L. Nitrate levels are primarily below the MCL of 10 mg/L, with slightly elevated concentrations in the Shallow Zone around Brentwood due to past land uses. Boron does not have a drinking water standard, but the agricultural goal is 700 ug/L where some crops may become sensitive to it. Boron concentrations in ECC wells are generally over 1,000 ug/L. • Groundwater Storage: the total volume of groundwater in storage in the Subbasin was estimated to be between 4.5 MAF and 9 MAF when measuring to the base of fresh water (to over 1,000 ft bgs) and between 1.5 MAF to 3 MAF when measuring the current production zone (to average of 300 ft bgs). There has not been a change in groundwater storage overtime because groundwater levels between 1993 to 2019 have been stable. • Land Subsidence: there are no historical records of inelastic subsidence due to groundwater withdrawal in the ECC Subbasin. • Seawater Intrusion: the East Contra Costa Subbasin is located in the Bay-Delta with the potential for interactions between saline baywater and shallow groundwater. While the baywater is fresh, intrusion may be of concern if saline water infiltrates the Delta and intrudes into shallow groundwater. This potential mechanism may be triggered or exacerbated by sea level rise. There are no direct connections between ocean seawater and groundwater in the Subbasin. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-84 • Interconnected Surface Water: are locations where groundwater and surface water are hydrologically connected. The San Joaquin River and Old River are considered interconnected rivers in this Subbasin. Impacts on these surface water bodies due to groundwater pumping will be managed under this GSP to minimize stream depletion. • Groundwater Dependent Ecosystems: potential GDEs are identified and GDE health is stable or improving. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-85 3.5 References Anderson, R. 1985. Geological Society, London, Special Publications, 18, 31-47, 1 January 1985, https://doi.org/10.1144/GSL.SP.1985.018.01.03. Bartow, J.A. 1985. Map showing Tertiary stratigraphy and structure of the Northern San Joaquin Valley, California, Field Studies Map MF-1761, Scale 1:250,000. Bartow, J.A. 1991. The Cenozoic Evaluation of the San Joaquin Valley, California. U.S. Geological Survey, Professional Paper 1501. Berkstresser, C.F., Jr. 1973, Map showing base of fresh ground-water, approximately 3,000 micromhos, in the Sacramento Valley and Sacramento-San Joaquin Delta, California: U.S. Geological Survey Water- Resources Investigations Report 40-73, 1 sheet. Bertoldi, G., Johnston, R., and Evenson, K.D., 1991, Regional Aquifer-System Analysis-Central Valley, California: U.S. Geological Survey Professional Paper 1401-A. Davis, T.A., Bennett, G.L., Metzger, L.F., Kjos, A.R., Peterson, M.F., Johnson, J., Johnson, T.D., Brilmyer, C.A., and Dillon, D.B., 2018, Data analyzed for the preliminary prioritization of California oil and gas fields for regional groundwater monitoring: U.S. Geological Survey data release, https://doi.org/10.5066/F7FJ2DV3. Deverel, S.J., Ingrum, T. Leighton, D. (2016). Present-day oxidative subsidence of organic soils and mitigation in the Sacramento-San Joaquin Delta, California, USA. Hydrogeology Journal. Distributed under the Creative Commons Attribution 4.0 International License. http://creativecommons.org/licenses/by/4.0/. Department of Water Resources (DWR). 2003. Bulletin 118: California’s Groundwater. DWR. 2016. Bulletin 118: California’s Groundwater, Interim Update 2016. DWR. 2017. Draft Best Management Practices for the Sustainable Management of Groundwater, Sustainable Management Criteria BMP. November 2017. DWR. 2021. Vertical Displacement TRE ALTAMIRA Annual Rate June 2015 to June 2019. https://gis.water.ca.gov/arcgisimg/rest/services/SAR. Accessed May 2021. GeoTracker. 2018. GeoTracker Cleanup Sites. https://geotracker.waterboards.ca.gov/datadownload ECCC IRWM. 2019. https://www.eccc-irwm.org/east-county-irwm Hydrofocus Inc. 2014. Dutch Slough Restoration Area Surface Water Quality Monitoring Report, September 2012 to August 2013. April 11, 2014. 228 pages. Klausmeyer, Kirk R., Tanushree Biswas, Melissa M. Rohde, Falk Schuetzenmeister, Nathaniel Rindlaub, Ian Housman, and Jeanette K. Howard. 2019. GDE Pulse: Taking the Pulse of Groundwater Dependent Ecosystems with Satellite Data. San Francisco, California. Available at https://gde.codefornature.org. Luhdorff and Scalmanini, Consulting Engineers. 1999. Investigation of Ground-Water Resources in the East Contra Costa Area. Prepared for East County water entities. March 1999. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 3 - BASIN SETTING LSCE 3-86 Luhdorff and Scalmanini, Consulting Engineers. 2016. An Evaluation of Geologic Conditions East Contra Costa County. Prepared for East Contra Costa County Agencies. March 2016. Page, R.W.,1973b, Base of fresh ground water (approximately 3,000 micro mhos) in the San Joaquin Valley, California: U.S. Geological Survey Hydrologic Investigations Atlas HA-489. Rohde, M. M., S. Matsumoto, J. Howard, S. Liu, L. Riege, and E. J. Remson. 2018. Groundwater Dependent Ecosystems under the Sustainable Groundwater Management Act: Guidance for Preparing Groundwater Sustainability Plans. The Nature Conservancy, San Francisco, California. Town of Discovery Bay Community Services District and Luhdorff and Scalmanini, Consulting Engineers. 2017. 2015 Urban Water Management Plan. Adopted June 21, 2017. UNAVCO. 2019. UNAVCO’s Monitoring Network Map database. https://www.unavco.org/instrumentation/networks/map/map.html#/Accessed on April 2019. University of California, Davis (UCD) Department of Agriculture and Natural Resources. n.d. Soil Resource Lab. Soil Agricultural Groundwater Banking Index (SAGBI). https://casoilresource.lawr.ucdavis.edu/sagbi/. Accessed May 2019. U.S. Geological Survey. 1999. Land subsidence in the United States: Sacramento-San Joaquin Delta. Circular 1182. Pages 83-94. Weier, John and Herring, David. 2000.Measuring Vegetation (NDVI & EVI). https://earthobservatory.nasa.gov/features/MeasuringVegetation. Accessed April 2021. Williamson, A. K., Prudic, D.E., and Swain, L.A., 1989, Ground-water flow in the Central Valley, California, U.S. Geological Survey Professional Paper 1401-D, 127p. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 - HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-i SECTION 4 CONTENTS Historical, Current and Projected Water Supply ........................................................................4-1 4.1 Land Uses ................................................................................................................................... 4-1 4.2 Population Trends ...................................................................................................................... 4-5 4.3 Water Demands, Supplies and Utilization ................................................................................. 4-8 4.3.1 Historic and Current Water Supplies ................................................................................. 4-8 4.3.2 Projected Water Demands and Supplies ......................................................................... 4-18 4.3.3 Water Availability and Reliability ..................................................................................... 4-19 4.4 References ............................................................................................................................... 4-21 LIST OF TABLES Table 4-1 Historic, Current and Projected Population…………………………………………………………………4-6 Table 4-2 Groundwater Extractions by Water Use Sector, Historical and Current, ECC Subbasin…………………………………………………………………………………………..…………………………4-9 Table 4-3 Historical and Current Metered Surface Water Supplies by Water Use Sector, ECC Subbasin…………………………………………………………………………………………………4-10 Table 4-4 Total Water Use by Source and Water Use Sector, ECC Subbasin……………………………….4-11 Table 4-5 Projected Water Demand and Supply (including Antioch and Brentwood areas outside the Subbasin)………………………………………………………………………………………………..4-12 LIST OF FIGURES Figure 4-1 Change in Land Use 1984-2016……………………………………………………………………………………4-4 Figure 4-2 Historical, Current, and Projected Population………………………………………………………………4-7 LIST OF APPENDICES Appendix 4a Individual Surface Water Diversions: Point of Delivery Totals by Tract/Model Subregion and by Calendar Year EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 - HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-1 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY This section describes the East Contra Costa (ECC) Subbasin land uses, population, and metered historical, current and projected water supplies. Water supply amounts were provided by the Groundwater Sustainability Agencies (GSA) and Contra Costa Water District (CCWD). When historical or projected water supply were not provided, land uses and population data was used to estimate these data. This information is integrated into the Subbasin surface water/groundwater model (GSP Section 5). 4.1 Land Uses Department of Water Resources Land Use Surveys Since the 1950s, DWR has periodically conducted detailed and high-quality land use surveys. The project began as an effort to understand water and land use as well as to understand current and projected water demands. DWR land use surveys conducted in Contra Costa County provide historical land use details of the Subbasin for the years 1976 and 1995 (Figures 2-11 and 2-10, respectively). The most current land use conditions for the Subbasin are derived from a Delta crop map for 2015 (Figure 2-9) integrated with a 2014 statewide map to fill in areas not covered by the former. The resultant map does not cover the entire Subbasin leaving small areas along the western boundary as not designated, approximately 6,200 acres, which is about 6 percent of the area of the Subbasin. These lands were assigned a land use based on the 1995 land survey and cross-checked with Google earth. The total area of the Subbasin is 107, 596 1 acres. A breakdown of land use categories reported in historical and current surveys is given in Table 2-3. In 1976, native vegetation and field crops were the major land use categories (about 25,000 and 23,000 acres, respectively), which collectively accounted for about 45 percent of the area within the Subbasin. Surface water and pasture (about 14,000 and 13,000 acres, respectively) covered about 25 percent of the land area. After field crops, deciduous trees and truck crops (e.g., melons and tomatoes) were the major cultivated crops (about 12,000 and 8,000 acres, respectively) accounting for about 18 percent of the area. Approximately 9 percent of the area in the Subbasin (about 9,700 acres) was designated as urban areas. The remaining land cover was comprised of semi-agricultural lands, idle lands, and vineyards. Between 1976 and 1995, acreage of urban lands (Figure 2-12) increased to about 19,000 acres (about 18 percent of the Subbasin area). Area of the idle lands increased from about 900 acres in 1976 to 5,800 acres in 1995 (from about 1 percent to 5 percent of the Subbasin area). During this period, both deciduous trees and field crops acreages decreased by about 5,700 and 5,000 acres, respectively. Decrease of pasture, native vegetation and truck crops were about 1,900, 1,600 and 950 acres, respectively. Acreages of the other land use categories remained nearly unchanged during this period. In 2015, the total area of urban lands was about 23,500 acres (22 percent of the Subbasin area), making it the largest single land use category within the Subbasin. Native vegetation coverage was about 15,500 acres (14 percent of the Subbasin area), which was a decrease of about 9,500 acres from 1995. A part of this decrease, approximately 4,000 acres may be attributed to the lands that were designated as native vegetation in previous surveys but categorized as “Not Designated” in the 2015 survey. Pasture and surface water bodies each covered about 14 percent of the Subbasin area (each about 15,000 acres). The 1 The California Department of Water Resources ECC subbasin boundary shape file was used to calculate the area in GIS based on the map projection. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 - HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-2 total area of all crop lands was about 23,000 acres (21 percent of the Subbasin area) in 2015. Field crops, which accounted for about 13,500 acres (13 percent of the Subbasin area) was the major crop category, and it showed a decrease of about 4,700 acres from 1995. Areas of truck crops, deciduous trees and vineyards totaled about 9,400 acres (about 9 percent of the Subbasin area). Semi-agricultural lands, which include farmsteads, feed lots (livestock and poultry), and dairies, increased from about 900 acres in 1995 to 6,300 acres in 2015 (6 percent of the Subbasin area). These figures indicate a transition from a predominantly agricultural area of field crops and other deciduous crops to a roughly even split between urban and agriculture. Within the Subbasin, a large area of native vegetation has been preserved over the time period evaluated (15,000 acres in 2015). The current Contra Costa County General Plan (CCC, 2005) extends until 2020. The county is presently working to develop its 2040 General Plan that will outline the planned land use for the unincorporated areas of the subbasin. The 2040 General Plan is expected to be available in late 2020. Farmland Mapping and Monitoring Program – Land Use Information California Department of Conservation, Division of Land Resource Protection, Farmland Mapping and Monitoring Program (FMMP) has reported on the ECCC Subbasin land use. Land use data for the Subbasin has been recorded since 1984 on a biannual basis. The FMMP has designated the following eight types of land use: 1. Prime Farmland- Irrigated land with the best combination of physical and chemical features able to sustain long term production of agricultural crops. This land has the soil quality, growing season, and moisture supply needed to produce sustained high yields. Land must have been used for production of irrigated crops at some time during the four years prior to the mapping date. 2. Farmland of Statewide Importance- Irrigated land similar to Prime Farmland that has a good combination of physical and chemical characteristics for the production of agricultural crops. This land has minor shortcomings, such as greater slopes or less ability to store soil moisture than Prime Farmland. Land must have been used for production of irrigated crops at some time during the four years prior to the mapping date. 3. Unique Farmland- Lesser quality soils used for the production of the state's leading agricultural crops. This land is usually irrigated but may include non-irrigated orchards or vineyards as found in some climatic zones in California. Land must have been cropped at some time during the four years prior to the mapping date. 4. Farmland of Local Importance- These lands (the Antioch area and the Delta) are typically used for livestock grazing. They are capable of producing dryland grain on a two-year summer fallow or longer rotation with volunteer hay and pasture. The farmlands in this category are included in the U.S. Natural Resources Conservation Service's Land Capability Classes I, II, III, and IV, and lack some irrigation water. 5. Grazing Land- Land on which the existing vegetation is suited to the grazing of livestock. This category is used only in California and was developed in cooperation with the California Cattlemen's Association, University of California Cooperative Extension, and other groups interested in the extent of grazing activities. 6. Urban and Built-Up Land- Urban and Built-Up land is occupied by structures with a building density of at least 1 unit to 1.5 acres, or approximately 6 structures to a 10-acre parcel. Common examples EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 - HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-3 include residential, industrial, commercial, institutional facilities, cemeteries, airports, golf courses, sanitary landfills, sewage treatment, and water control structures. 7. Other land- Land which does not meet the criteria of any other category. Typical uses include low density rural development, heavily forested land, mined land, or government land with restrictions on use. 8. Water- Water areas with an extent of at least 40 acres. All eight types of land use are present in the ECC Subbasin. The majority of land use has consistently been a type of farmland. Prime farmland has been the highest percentage of land use in the Subbasin since 1984 (Figure 4-1). Prime farmland had steady decline from 1984 to 2008 and from 2009 to 2016 the acreage was stable. Since 1984 there has been an increase in urban and farmland of local importance. The data produced by FMMP is not as detailed compared to DWR land use data. FMMP collects its data from aerial images, public review, computer mapping, and field inspections. The data provides the ECC Subbasin an approximation of changes in land use over time that supports DWR land use data findings of increasing urban land and decreasing farmland. Irrigation Methods DWR has irrigation data for the 1976 and 1995 land use surveys. The 1995 land use surveys also detail the irrigation method used. About 52 percent of lands in the ECC Subbasin were designated as irrigated in the 1976 survey. That percentage has decreased to about 45 percent in 1995, mainly due to increased urbanization. In the 1995 survey, DWR categorize irrigated lands into four groups based on irrigation methods employed in those lands: Gravity - Surface Irrigations (most common method in the Subbasin area) Micro - Low volume irrigation such as drip and micro spray Sprinkler- Permanent, solid set, and movable sprinkler systems • Irrigation method unknown The crop map data sets of 2014 and 2015 provided by DWR do not include irrigation details. However, recent information on irrigation methods are available from local agencies that provide irrigation water. Byron Bethany Irrigation District (BBID) reports that in 2014 2 approximately 50 percent (3,100 acres) of irrigated lands in its service area uses drip and micro-spray methods (BBID, 2017 AWMP). Flood irrigation and sprinklers are used in about 39 percent and 11 percent of irrigated lands, respectively. Drip and micro-spray methods are the primary irrigation methods in the ECCID service area (personal communication, Aaron Trott, August 2020). 2 Since 2016, and in response to drought conditions, the percent of irrigated lands using drip and micro-spray methods has increased to nearly 90 percent, mostly a switch from prior flood irrigation methods. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 - HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-4 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 - HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-5 4.2 Population Trends The East Contra Costa County region has exhibited increasing population growth over time (ECCC IRWMP, 2019). The Cities of Antioch, Brentwood, Oakley and the unincorporated communities of Town of Discovery Bay, Bethel Island, Byron, and Knightsen located within the ECC Subbasin have exhibited an increasing trend of population at variable rates. Parts of Antioch and Brentwood are located outside the ECC Subbasin. Therefore, in the following discussion, population of those two cities are proportioned based on the area located within the Subbasin (74 percent of the City of Antioch and 90 percent of the City of Brentwood). The comparatively smaller populations in rural areas in the Subbasin (i.e., outside the boundaries of cities, towns, and service areas of public water supply entities) are uncertain and are not included in the estimates presented in this discussion. Historical, current, and projected populations of the cities and unincorporated communities are given in Table 4-1 and shown in graphical form in Figure 4-2. Populations for 1950 through 2010 are based on the US decennial census data. Estimated population of 2015 through 2040 are based on the projections presented in 2015 Urban Water Management Plans (UWMP) of City of Antioch, City of Brentwood, and the Diablo Water District, as well as the Town of Discovery Bay 2020 Draft UWMP (population of 2020- 2045) and the City of Antioch 2020 Water System Master Plan Update Technical Memorandum (Brown and Caldwell, 2020), and the DWD 2020 Facilities Plan (CDM Smith, 2020). Projections for 2045 and 2050 were obtained by applying the countywide population growth rate provided in CA Department of Finance Population Projections as detailed below. According to the US census data, the total population within the ECC Subbasin in 2010 was about 176,000. Population in the Cities of Antioch, Brentwood and Oakley were about 75,500, 46,300 and 35,400, respectively. In unincorporated communities, the Town of Discovery Bay (TODB) had the highest population (about 13,400) and the other three communities had a combined population of about 5,000. Historical data show that the population of the Cities of Antioch, Brentwood and Oakley increased at a rapid rate (112 percent, 426 percent, and 800 percent, respectively, or 198 percent in their combined areas, from 1980 to 2000 (Figure 4-2). The growth rate has decreased since then but remained higher than the overall growth rate of Contra Costa County (49 percent in the three cities in the ECC Subbasin versus 22 percent in the County). The eastern region of the County in which the Subbasin is situated “is expected to be the fastest growing area of the County in the foreseeable future” (ECCC IRWMP, 2019). As the Cities reach the build-out population limits in 2040, growth is expected to continue but at a slower rate. This post-2040 slower growth rate was the basis to apply the countywide growth rate to estimate the 2045 and 2050 population given in Table 4-1. The total population in the Subbasin is expected to increase to about 264,000 in 2040 and 279,000 in 2050, which correspond to increases of 50 percent and 59 percent compared to 2010 population (Table 4-1). For these same time periods, the countywide population has an expected growth rate of 27 percent (2040) and 32 percent (2050) relative to 2010 population (Department of Finance Population Projections, 2019). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-6 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-7 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-8 4.3 Water Demands, Supplies and Utilization The purpose of defining water demand (outflows) and supplies (inflows) is that they contribute to the understanding of the ECC Subbasin water budget. This section describes the groundwater and surface water components of the water budget that are measured (e.g., groundwater pumping and surface water deliveries). Other water budget components will be developed in the groundwater/surface water model described in Section 5. A water budget accounts for the total groundwater and surface water entering and leaving a subbasin and are necessary to develop a sustainable water budget for the ECC Subbasin. 4.3.1 Historic and Current Water Supplies Annual water usage and sources of water supply from 1985 to 2019 by seven entities in the Subbasin are provided in Tables 4-2 and Table 4-3. Table 4-2 lists annual metered groundwater extracted by water use sector (urban, industrial, and agricultural). Groundwater production by domestic well users (de minimis user) and small community systems are not metered but are estimated and described below. Groundwater use by private agricultural wells and native vegetation are estimated in Section 4. Table 4-3 lists annual metered surface water use for the seven entities by sector and individual surface water diverters with water rights permits. Table 4-4 lists the total water use by source and water use sector from 1985 to 2019. Projected available supplies and water demand (2020 through 2050) for the seven entities are provided in Table 4-5. Below is a description of the seven retail and wholesale water suppliers that operate within the Subbasin, their water rights, and sources of water. Surface water diverted out of Old River for uses outside the ECC Subbasin (e.g., California Aqueduct and the Delta Mendota Canal) does not play a role in supplying water to fulfill the demand of the Subbasin and is therefore not included in the water budget. Byron Bethany Irrigation District The BBID service area extends beyond the ECC Subbasin boundaries, into the adjacent Tracy and Delta Mendota Subbasins. Byron and a portion of the Bethany Divisions of BBID are located within the ECC Subbasin. For purposes of this GSP, only the reported Byron Division supply will be used and the small portion of the Bethany Division that falls in the ECC Subbasin will not be estimated. The Byron and Bethany Divisions are served by the District’s pre-1914 water rights of 50,000 AFY 3. Water is obtained from the intake channel at the Harvey O. Banks Pumping Plant located between the Byron and Bethany Divisions and delivered to customers through distribution canals. During normal conditions, water is delivered for agricultural uses from March to November. During drought periods (e.g., 2013-2015) the water delivery period was extended depending on supply and demand conditions. From 1997 to 2019, the pre-1914 surface water supply to the Byron Division ranged from about 7,000 AF (2017) to 28,000 AF (2009) and averaged about 14,500 AFY (Table 4-3). In 2015, during the drought, available surface water was not sufficient to meet water demands of the service area. Byron Division received two additional sources of water: about 2,000 AF purchased (transfer) water and, for the first time in its operational history, BBID obtained about 510 AF of groundwater (3 percent of total supplies) from private well owners in the Byron District. BBID does not maintain records on groundwater use for irrigation by private well owners in the District. 3 Ch2M, 2017: “The District asserts claims under this pre-1914 water right for reasonable and beneficial use of 60,000 AF. In exchange for operational certainty, the District has agreed to limit their annual diversion from the Delta to 50,000 AF through their Agreement with DWR” EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-9 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-10 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-11 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 - HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-12 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-13 City of Antioch The City of Antioch (Antioch) relies entirely on surface water for water supply. Antioch purchases raw water from CCWD and pumps water from the Sacramento-San Joaquin Delta when the chloride concentration is not over 250 milligrams per liter (mg/L). The current agreement between Antioch and CCWD is for a peak supply of 40,000 AFY (WYA, 2015). Antioch’s water right to obtain water from the Delta for beneficial use does not specify a limitation, but the withdrawal rate is currently constrained to about 18,000 AFY by pumping and conveyance systems. Raw water from both sources can be directly pumped to Antioch’s Water Treatment Plant (WTP) or into a municipal reservoir (Antioch Reservoir, Figure 2-41) for storage. The municipal reservoir has a capacity of 736 AF and is used to maintain a reliable supply to the WTP when the ability to pump from the Delta is limited due to water quality. The maximum capacity of the WTP is over 40,000 AFY. From 1997 to 2019, surface water supplies for the entire City of Antioch ranged from a low of around 14,000 AFY (2015 to 2017) to a high of 19,000 AFY to 21,000 AFY (2001 to 2008). However, 26 percent of the City’s jurisdiction falls outside the ECC Subbasin. To account for this, the total Antioch supply is adjusted in Table 4-3 to remove the estimated 26 percent delivered to the portion of the city that falls outside the Subbasin. The adjusted surface water supply for the Subbasin ranges from around 10,000 AFY to 11,500 AFY (2015 to 2019) and 14,000 AFY to 16,000 AFY (2001 to 2008). The reduction in demand in recent years (2015 to 2019) is due to changes in customer water use patterns since the recent drought. As a result, projected demands are expected to decrease due to conservation and continuation of the drought-influenced water use patterns through 2040. Antioch’s projected total water demand (Table 4-4) is expected to increase to about 13,500 AFY in 2050 with 12,000 AFY derived from surface water and 1,500 AFY from recycled water. Since 2011, the City has purchased recycled water from Delta Diablo for landscape irrigation, which currently accounts for about 0.25 percent of the City’s total water usage. The City of Brentwood The City of Brentwood (COB or Brentwood) uses three sources of water to meet demand: surface water, groundwater, and recycled water. In 1999, Brentwood entered into an agreement with ECCID to obtain up to 14,800 AFY of raw surface water that is pumped from the Delta. The majority of water is transported from the Rock Slough intake through the Contra Costa Canal to the City of Brentwood Water Treatment Plant (COBWTP). The COBWTP was constructed in 2008 jointly by the City and CCWD. The current capacity of the COBWTP is 18,500 AFY 4 (16.5 million gallons per day [MGD]), but it can be increased to 36,000 AFY to meet future water demand. In addition, raw surface water used for landscape irrigation is purchased from ECCID and transported through their Main Canal. A portion of the ECCID entitlement is treated at the Randall-Bold Water Treatment Plant (RBWTP) under an agreement with CCWD 5. In a 1999 agreement with a 2000 amendment, COB has a permanent capacity of around 3,200 AFY (6 MGD) at the RBWTP6. Historically, surface water purchased by COB from both ECCID and CCWD has increased from a low in 1994 to 1999 (less than 1,000 AFY) to the higher range in 2007 to 2019 (6,300 AFY to 9,600 AFY). Future surface water supply (to 2050) is expected to not exceed the current allocation of 14,800 AFY. 4 Personal communication, Eric Brennan, City of Brentwood November 13, 2020. 5 Even though this water is provided under an agreement with CCWD it is included as part of the total 14,800 AFY agreement with ECCID; it is not CVP water. 6 Personal communication, Jill Mosley, CCWD, November 13, 2020. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-14 As of 2015, the City has seven active groundwater production wells within its service area. Capacity of the active wells in 2015 was over 7,000 AFY (COB 2015 UWMP). From 1998 to 2019, COB pumped between 1,300 AFY (2016) to 5,800 AFY (2006). On an annual basis, contribution of groundwater has decreased in relation to the total city demand over the last 25 years. COB groundwater supply percentage was the highest from 1994 to 1999 with 80 percent to 90 percent (2,000 AFY to 4,000 AFY). From 2000 to 2006, 50 percent to 70 percent (3,600 AFY to 5,800) of COB water supply was from groundwater. In the last 13 years groundwater supply decreased to 15 percent and 25 percent (1,300 AFY to 3,000 AFY) in normal years and from 30 percent to about 40 percent (4,000 AFY to 5,000 AFY) in drought years (2007 to 2009 and 2013 and 2014) as a result of the greater use of surface water sources. Future City pumpage is expected to not exceed 5,600 AFY through 2050 (Table 4-4). Recycled water provided by the City’s wastewater treatment plant has been used for landscape irrigation and industrial purposes. Recycled water has accounted for less than 1 percent to 5 percent of the total water supply of the City since 2005 when recycled water became available. Projected buildout recycled water demand for 2040 was estimated at 1,500 AFY (COB 2015). Contra Costa Water District CCWD is a regional water supplier to entities within and outside the Subbasin. It has a contract with the United States Bureau of Reclamation (USBR) for 195,000 AF per year through February 2045 (CDM Smith, 2016). The Sacramento-San Joaquin Delta (Delta) is the primary source of water and CCWD receives this water from the Central Valley Project (CVP). CCWD also obtains water through Delta surplus water right, Mallard Slough water rights and transfers from ECCID, as well as uses recycled water and a minor amount of local groundwater (CCWD, 2016). CCWD serves both as a retail and wholesale water supplier to the northern, eastern, and central parts of Contra Costa County but only CCWD surface water supplies for the ECC Subbasin will be discussed here. In the ECC Subbasin area, CCWD is a wholesale supplier of treated and raw water to the City of Antioch and Diablo Water District (DWD). CCWD also diverts and conveys ECCID surface water for the City of Brentwood. CCWD water supplied to these three entities is listed in Table 4-3 under the entity name. Water supplied to these entities is pumped from Rock Slough, Old River, and Victoria Canal (Middle River) intakes located in the Sacramento-San Joaquin Delta (Delta) and, is treated at the RBWTP and COBWTP. The RBWTP is jointly owned by CCWD and DWD and operated by CCWD and primarily serves the Subbasin. Water pumped from Old River and Victoria Canal intakes can be stored in the Los Vaqueros Reservoir, which has a 160,000 AF capacity, and released when supplies from the Delta are limited due to poor water quality. In addition, CCWD supplies agricultural water (Table 4-3) to the Antioch area inside the ECC Subbasin. These agricultural water supplies within the Subbasin (Antioch area) have ranged from 60-100 AFY (1994-2001) to 2-5 AFY (2015-2019). Future agricultural demands may decrease further depending on the conversion of agricultural lands to urban. Diablo Water District DWD supplies water to the City of Oakley, the Town of Knightsen, and some areas of Bethel Island. DWD uses two sources of water to meet demand (CDM Smith, 2020), the primary source is surface water with additional supply from groundwater (10-20 percent, 2007 to 2019). Surface water is purchased from CCWD, supplied from the Contra Costa Canal and the Los Vaqueros Project, and treated at the RBWTP. DWD’s current capacity of the RBWTP is 8,400 AFY but this can be increased to 16,800 AFY per agreement with EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-15 CCWD. DWD purchases CVP water from CCWD which has a contract with the US Bureau of Reclamation (USBR) for 195,000 AFY through February 2045. From 1994 to 2019 total water supply ranged from around 3,000 AFY (2001) to about 6,400 AFY (2007 and 2008). DWD’s surface water supply has ranged from 3,100 AFY (2001) to 5,500 AFY (2007) (Table 4-3) and groundwater supply has ranged from a low of 0 AFY (2001-2005) to a high of 1,300 AFY (2011) (Table 4-2). From 2012 to 2019, groundwater supply has averaged about 800 AFY. Future demand is dependent on rate of DWD’s growth and consumer conservation but is expected to be about 14,000 AFY in 2040 with 80 percent met by surface water and 20 percent met by groundwater (Table 4-4). DWD is proposing the installation of two new groundwater production wells in the vicinity of the Glen Park well (south-central portion of the District) in the next 10 to 20 years. Groundwater is currently pumped from two wells in Oakley, then conveyed to the Blending Facility, where it is treated and blended with treated surface water prior to distribution to customers. The Blending Facility is operated so that the distributed water does not exceed 280 mg/L total dissolved solids (TDS). During water shortages this may be relaxed by DWD to 500 mg/L (TDS). Groundwater is supplied year- round because it can be provided at a lower cost than surface water. DWD does not use recycled water for any beneficial use. Ironhouse Sanitary District (ISD) owns and operates the wastewater treatment system in DWD’s service area and also includes Bethel Island, Jersey Island, and part of Holland Tract. In 2011, ISD completed construction of the Waste Recycling Facility producing tertiary-treated recycled water. The operating capacity is currently 4,800 AFY with an expansion capacity up to 7,600 AFY. The recycled water is currently applied on agricultural land owned by ISD (on Jersey Island), provided at fill stations, or discharged to the San Joaquin River. Other groundwater pumping in the DWD service area is described in the Oakley General Plan (City of Oakley, 2016 amended) that states that over 30 small water companies or service districts serving less than 5,000 people are located in the eastern portion of the District’s sphere of influence (SOI). Also, within the District’s SOI are residences with individual domestic wells, generally shallower than 200 feet, that are considered di minimis users for SGMA purposes. However, these wells will be considered as beneficial users and potentially impacted by other groundwater pumping as discussed further below. The Oakley General Plan has a policy (4.8.8) that encourages rural residences currently served by well water to connect to municipal water service when it becomes available. DWD assumes that the small water systems would be replaced by a system meeting DWD standards when DWD treated water service becomes available in these areas (CDM Smith, 2020). East Contra Costa Irrigation District The East Contra Costa Irrigation District (ECCID) is an independent special district established in 1926. The primary purpose of ECCID is to provide agricultural irrigation water to properties within the District boundaries. In addition, it provides raw water for treatment facilities in urban areas. ECCID’s approximately 40 square mile service area includes the City of Brentwood, parts of the Cities of Antioch and Oakley, the unincorporated community of Knightsen, and unincorporated areas located south and east of Brentwood. Water is supplied primarily from surface water diverted from Indian Slough off Old River but is also supplemented with groundwater. ECCID holds pre-1914 water rights for up to 50,000 AFY, that is not subject to delivery reduction during water shortages including regulatory-restricted and drought years. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-16 Surface water provided for agricultural irrigation ranged from about 30,000 AFY to 34,000 AFY) between 1994 to 2000 to about 17,000 AFY in 2017 and 2018 (Table 4-3). The decrease reflects the conversion of agricultural lands to urban lands within ECCID’s service area. ECCID also operates nine groundwater wells (ECWMA, 2019) that generally pump between 300 to 800 AFY in normal years and increases to between 1000 to 4,000 AFY in drought years (2008, 2009, 2014, and 2015). As mentioned above, CCWD has an agreement with ECCID to provide groundwater to CCWD when there is a shortage of CVP water as represented in ECCID’s drought year pumping. ECCID provides surface water to Brentwood and CCWD through agreements described below. These annual surface water diversions for Brentwood and CCWD are tabulated under the Brentwood heading in Table 4-3. • In 1999, Brentwood and ECCID entered into an agreement under which ECCID would provide up to 14,800 AFY of raw water each year. The water is available on Indian Slough, Rock Slough, or the intake on Old River to the Vaqueros Project. The City treats and distributes water to customers located within the City or ECCID boundaries. • In 2000, CCWD and ECCID entered into an agreement in which ECCID provides up to 8,200 AFY surplus irrigation water to CCWD to serve municipal and industrial needs within the overlapping areas of the two agencies. Furthermore, ECCID may provide up to 4,000 AFY of groundwater to CCWD by exchange for the use within the CCWD service area when there is a shortage of CVP water. In the future, ECCID anticipates some reduction in agricultural lands, however, these lands have been fallowed for many years so water demand by the agricultural core area is not expected to change and would remain at about 20,000 AFY. In the next 15 years, ECCID expects a 15 percent increase in urban non-potable landscape water deliveries for Brentwood that is fed through the ECCID main canal. The Town of Discovery Bay TODB Community Services District operates the public water supply system of the Town. The TODB relies exclusively on groundwater. Raw water pumped from six groundwater wells are treated at two water treatment plants (Willow Lake WTP and Newport WTP) located in the area. The combined capacity of wells is approximately 16,000 AFY, while the combined capacity of the two water treatment plants is approximately 12,000 AFY. Groundwater pumped between 1994 varied from about 1,800 AFY in 1994 to over 4,000 AFY in the drought years of 2007 to 2009 (Table 4-2). The District operates two wastewater treatment facilities, but recycled water is not used for any beneficial purpose because it is not cost effective and all water demands can be sustainably met with groundwater. Projected demand is expected to reach about 6,200 AFY by 2040 that will be met entirely by groundwater (Table 4-4). Small Water Systems and De Minimis Users Additional groundwater is pumped in the Subbasin by small public water systems (PWS) and rural domestic (de minimis) wells that are not metered. In order to estimate groundwater pumped by the PWS, a variety of information was collected. In 2018, Contra Costa County Environmental Health reported 62 small public water systems (those with <200 connections) in the ECC Subbasin. This list was refined with duplicates removed leaving 51 PWS currently in the ECC Subbasin. These consisted of a variety of facilities including marinas, schools, churches, a golf course, restaurants, and mutual water companies. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-17 However, the County does not estimate total groundwater demand by these users. The California State Water Resources Control Board (Water Board) collects self-reported annual inventory information of public water systems. As per the most recent data available from the Water Board7 (reporting year 2016, data set updated in October 2019), 26 small water systems owned by local governments or private parties exist within the ECC Subbasin. These water systems are designed to serve a population of more than 4,500. Reported data from 11 water systems show that about 83 AFY of water, entirely obtained from groundwater wells, has been distributed to a population of about 2,300 in 2016. Supply details of the other 15 water systems are not available. To account for these groundwater users, an estimate was assigned of about 500 AFY total water for the PWS. PWS locations and groundwater demand have been identified as a data gap and will be refined over the next five years. DWR’s well completion report database 8 lists about 975 domestic wells (de minimis user) in the ECC Subbasin (Figure 2-6a). This list was refined to remove any well installed over 30 years ago (assuming that a domestic well life span is 30 years) leaving about 620 domestic wells. It was assumed that the average domestic well pumps about 19 AFY; domestic wells in the ECC subbasin produce about 600 AFY. The number of domestic wells, their locations, and average water use has been identified as a data gap and will be refined over the next five years. Individual Surface Water Diversions Individual surface water diversions are made by those with water rights permits and are reported by the State Water Resources Control Board (SWRCB). Table 4-3 lists the annual amount reported 10 as diverted by individual water rights holders in the ECC Subbasin and ranges in the last 10 year from between 114,000 AFY (2018) to 196,000 AFY (2013). California Water Code § 5101 requires individual surface water diversions made by those with water rights permits to report water diversion to the state on an annual basis. At present, there are 272 currently active “Application Numbers”, each of which uniquely identifies a surface water diversion point and its owner, in the ECC Subbasin. However, the Electronic Water Rights Information Management System (eWRIMS) of the SWRCB does not contain diversion records of any of those Application Numbers until 2008. Diversion data of about 15% of Application Numbers are available for 2009, but that percentage is 68% for 2010, 79% for 2015 and 95% for 2019. Appendix 4a lists the diversions by tract and subarea. The State Water Board acknowledges that the data is uncertain, possibly due to a mix of units (gallons vs acre-feet) and/or double reporting 11 and they are working to improve the reporting. For purposes of calculating total water use in the ECC Subbasin, these amounts are used and will be refined in the future. 7https://data.ca.gov/dataset/drinking-water-public-water-system-annually-reported-water-production-and- delivery-information. Downloaded July 14, 2020. 8 Downloaded May 2019. 9 Estimate for domestic well pumpage: 100 gallons/day/person x 4 persons/household*365 days/year=about .5 AFY plus extra for irrigation= total for one domestic well annual pumpage 1 AFY. 10 Monthly self-reported surface water diversions for the years 2008-2019 downloaded from: https://ciwqs.waterboards.ca.gov/ciwqs/ewrims/reportingDiversionDownloadPublicSetup.do. GIS files of Points of Diversion downloaded from: https://waterrightsmaps.waterboards.ca.gov/viewer/index.html?viewer=eWRIMS.eWRIMS_gvh# 11 Michael George, Delta Watermaster, Delta Protection Commission meeting, September 17, 2020. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-18 Summary In the previous 10 years (2010 to 2019), the ECC Subbasin total metered and estimated water use (Table 4-4) has ranged from, 173,000 AFY (2018) to, 214,000 AFY (2013). Sources of water supplies during this same time frame included: surface water ranging from 165,000 AFY to 259,000 AFY (95 percent to 97 percent of total supply); groundwater supplies range from about 6,000 AFY to 11,000 AFY (3 percent to 5 percent of total supply); and recycled water supplies ranged from 50 AFY to 500 AFY (less than 1 percent of total supply). 4.3.2 Projected Water Demands and Supplies Table 4-5 provides the projected water demand from 2020 to 2050 in five-year intervals within the service area of each supplier. Note that projections are for major water users and do not include unmetered di minimis users, PWS, or individual surface water diverters. Estimated demands and supplies for the 2020-2040 period were obtained from the following sources: 2015 or draft 2020 Urban Water Management Plans of the water suppliers, Technical Memorandum of City of Antioch 2020 Existing and Projected Water Use, Diablo Water District 2020 Facilities Plan, and personal communication (ECCID and BBID). Water demands for 2045 and 2050 were estimated using the projected population for those years and 2040 per capita water demands given in UWMPs and other reports. Available supplies for the 2045 and 2050 were assumed to be equal to the supplies estimated for 2040 in UWMPs. As mentioned above, population in the ECC Subbasin will be increasing and water demand in service areas of water suppliers are expected to stay the same or increase with the new development in the area. In comparison to reported water supplies in 2019, water demand in 2050 is projected to decrease by 7 percent in Antioch because of water conservation practices. Irrigation water demand of ECCID and BBID service area is expected to remain nearly unchanged during the projected period. Projected water demands for all other entities are expected to increase with population growth and other developments in the area. Within the same period, the increase of water demand will be about 70 percent in Brentwood, 170 percent in both the DWD and TODB service areas. The demand for water is expected to increase: for surface water from the 2019 amount 12 (50,000 AF) to the 2050 amount 13 (68,000 AF), for groundwater 14 from the 2019 pumped amount (10,000 AF) to the projected amount in 2050 (15,000 AF), and recycled water from the current 2019 amount (400 AF) to the projected 2050 amount (3,000 AF). In 2050, groundwater is expected to supply 17 percent (15,000 AFY) of the ECC Subbasin demand which is an increase of 5,000 AFY from 2019. 12 All 2019 amounts are from Table 4-3 for the ECC Subbasin only, 13 2050 amounts are from Table 4-4 and are for the entire ECC Subbasin. 14 Note that groundwater totals from 2019 and projected 2050 include an estimated groundwater use for domestic wells and public water systems totally 4,000 AFY. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-19 4.3.3 Water Availability and Reliability Historically, 80 to 87 percent of annual water demand in the Subbasin was met with surface water (2000 – 2019 period). Availability of water from the Delta, the primary source of surface water, largely depends on water quality and water rights. It has been reported that the water quality of the Delta has been degrading regardless of the measures taken to improve it (CCWD, 2015 UWMP). CCWD, one of the main water suppliers in the Subbasin, identified several contributing factors to deteriorating water quality in its 2015 UWMP. Changes in local and regional precipitation patterns can affect the timing and quantity of freshwater flow into the Delta. Lack of local precipitation and reduced flow from the upstream contribute to increased salinity levels in the Delta. Excessive pumping of Delta water and sea level rise can increase the salinity of the Delta water. • Increased flows of wastewater, storm water and agricultural drainage to the Delta also degrade the water quality of Delta. Water quality of the Delta is generally evaluated using its chloride concentration. The secondary maximum contaminant level of chloride in drinking water is 250 mg/L. Historically, chloride concentration at Delta water intakes has fluctuated between 20 and 250 mg/L (DWD, 2015 UWMP), but periods where daily mean chloride concentration increased over 1,000 mg/L have been reported (CCWD, 2010). The Los Vaqueros reservoir (160,000 AF capacity) is used to store higher quality Delta water to blend with high salinity water pumped from the Delta during late summer and fall months as well as dry periods. Furthermore, the reservoir can provide emergency supply; a minimum of 70,000 AF in wet years and 44,000 AF in dry years (CCWD, 2015 UWMP). Another critical factor that affects availability of CCWD CVP water from the Delta is regulatory actions imposed due to biological opinions associated with environmental protection. As per some biological opinions, quantity and timing of CVP and State Water Project water supplies used for urban or irrigation purposes may be limited when environmental supplies are prioritized. As a policy, CCWD plans to meet the entire demand in normal years and meet 85 percent of demand during drought periods. The unmet supply of 15 percent is to be managed with short-term demand management measures. The City of Antioch, which entirely relies on surface water to meet its water demands, is expected to meet 100 percent of the projected water demands in normal years (COA, 2015 UWMP). During drought conditions, at least 85 percent of the 2040 projected demand will be met during the third year of a drought period. The deficiency of supplies will be managed with short-term water purchases and short-term water conservation programs during droughts. Raw and treated water supplies that Brentwood receives may be affected by the limitations of availability of surface water. At present, groundwater quality of the City’s active supply wells meets potable water quality requirements. Groundwater is pumped from the Tulare Formation from wells perforated from 200 to 500 ft deep. Relatively high total dissolved solids (TDS), nitrate and chloride concentrations have been reported in shallow groundwater, but water quality improves with the increasing depth. If necessary, in the future, groundwater will be mixed with surface water to preserve quality. Available supplies exceed the 2040 projected water demand even in the third year of a drought period (COB, 2015 UWMP). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-20 DWD is capable of meeting 100 percent of 2040 projected water demand in normal years and until the first year of a drought period only with water received from CCWD RBWTP (CDM Smith, 2016). Surface water supplies from CCWD are expected to fulfil up to 94 percent and 85 percent of the 2040 projected demand in the second and third years of a drought period, respectively. The remaining demand will be met with groundwater supplies from the District’s wells. DWD plans to increase the groundwater supply up to about 20 percent of the total supplies by 2030 (CDM Smith, 2020) and it is expected to remain at 20 percent through 2040. However, if sufficient amounts of groundwater are not available during drought periods, DWD will request additional water from CCWD, explore other local sources, and/or implement water conservation programs as needed. TODB, which uses groundwater to meet its entire water demand, has been conducting a groundwater monitoring program since 1980s. The perforated interval of supply wells ranges from 250 to 350 ft bgs. Groundwater water level data indicate that groundwater pumping has been sustainable, even during the 2013 to 2015 drought period (TODB, 2015 UWMP). Groundwater quality from its supply wells meet all state of California primary drinking water standards. Manganese concentration exceeds the maximum limit specified in the secondary standards (0.005 mg/L); therefore, water is treated to remove excess manganese before distribution. Groundwater supplies can meet 100 percent of 2040 projected water demand during the third year of a drought period. Both irrigation districts (BBID and ECCID) have pre-1914 rights which is projected to meet the Districts’ water demands in 2050. To prepare for reliable water during droughts, BBID has executed an agreement with CCWD for an intertie between the Byron Division Canal 45 and the Old River Pipeline to allow storage of BBID water in the Los Vaqueros Reservoir for later use in the Byron Division and to facilitate water transfers with CCWD (Ch2M, 2017). Available supplies for the BBID, Antioch, Brentwood, CCWD, DWD, ECCID, and TODB meet or exceed the projected water demand of 2050 in normal years. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 4 HISTORICAL, CURRENT AND PROJECTED WATER SUPPLY LSCE 4-21 4.4 References City of Antioch. 2020. Technical Memorandum - 2020 Water System Master Plan Update. Prepared by Brown and Caldwell. February 2020. CDM Smith. 2016. Final 2015 Urban Water Management Plan. Prepared for Diablo Water District. CDM Smith. 2020. 2020 Facilities Plan. Prepared for Diablo Water District. June 2020. Ch2M. 2017. Byron Bethany Irrigation District Agricultural Water Management Plan. Prepared for Byron Bethany Irrigation District. October 2017. City of Oakley. 2016. City of Oakley 2020 General Plan. Adopted December 2002, amended February 2016. City of Brentwood (COB). 2016. 2015 Urban Water Management Plan, Prepared for the City of Brentwood by Brown and Caldwell. June 2016 Contra Costa County Department of Conservation and Development. 2005. Contra Costa County General Plan. January 18, 2005 (Reprint July 2010). Contra Costa Water District (CCWD). 2016. 2015 Urban Water Management Plan for the Contra Costa Water District. June 2016. Contra Costa Water District (CCWD). 2010. Historical Fresh Water and Salinity Conditions in the Western Sacramento-San Joaquin Delta and Suisun Bay - A summary of historical reviews, reports, analyses, and measurements. February 2010. Contra Costa Water District (CCWD). 2015. Urban Water Management Plan. June 2016 East Contra Costa County. 2007. Waste and Wastewater Services Municipal Services Review for East Contra Costa County, Prepared for Contra Costa Local Agency Formation Commission by Dudek. December 2017 East Contra Costa County. 2015. East Contra Costa County Integrated Regional Water Management Plan. September 2015 East Contra Costa County. 2019. East Contra Costa County Integrated Regional Water Management Plan Update 2019. March 2019 Town of Discovery Bay Community Services District. 2017. 2015 Urban Water Management Plan. May 2017 West Yost Associates (WYA). 2016. City of Antioch 2015 Urban Water Management Plan. Prepared for City of Antioch. May 2016. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-i SECTION 5 CONTENTS 5. Water Budget (§ 354.18) ........................................................................................................... 5-1 East Contra Costa Subbasin Hydrologic Base Period ................................................................... 5-1 Summary of Water Year 2015 Hydrologic Conditions ................................................................. 5-2 Projected 50-Year Hydrology (§354.18c3) ................................................................................... 5-2 Water Budget Framework ........................................................................................................... 5-3 Groundwater/Surface Water Flow Model ................................................................................... 5-5 Subbasin Water Budget Results (§354.18a, b, c and d) ............................................................. 5-14 Model Calibration and Uncertainty ........................................................................................... 5-49 Sensitivity Analysis (TBD) ........................................................................................................... 5-51 Sustainable Yield Scenario ......................................................................................................... 5-51 GSA Area Water Budget Results ................................................................................................ 5-56 Model Documentation .............................................................................................................. 5-66 References ................................................................................................................................. 5-66 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-ii LIST OF TABLES Table 5-1. Water Budget Components ............................................................................................... 5-4 Table 5-2 Water Balance Subregions ............................................................................................... 5-11 Table 5-3. Water Budget Accounting Components Simulated Using ECCSim .................................. 5-15 Table 5-4. Simulated Land and Water Use Budget Components for Base Period, WY 1997-2018 (Units in Acre-Feet per Year, AFY) ................................................................................... 5-18 Table 5-5. Simulated Root Zone Budget Components for Base Period, WY 1997-2018 (Units in Acre-Feet per Year, AFY) .................................................................................................. 5-19 Table 5-6. Simulated Groundwater Budget Components for Base Period, WY 1997-2018 (Units in Acre-Feet per Year, AFY) .................................................................................................. 5-21 Table 5-7. Simulated Groundwater Inflow Components for Base Period, WY 1997-2018 (Units are in Acre-Feet per Year, AFY) ........................................................................................ 5-23 Table 5-8. Simulated Groundwater Outflows for Base Period, WY 1997-2018 (Units are in Acre-Feet per Year, AFY) .................................................................................................. 5-25 Table 5-9. Simulated Groundwater Storage Component for Base Period,WY 1997-2018 (Units are in Acre-Feet per Year, AFY) ........................................................................................ 5-27 Table 5-10. Water Year Types During the Base Period ....................................................................... 5-29 Table 5-11. Simulated Agricultural and Urban Supply and Demand (Units in Acre-Feet Per Year, AFY) .................................................................................................................................. 5-30 Table 5-12. Average Simulated Groundwater Budget Components by Water Year Type (Units in Acre-Feet Per Year, AFY) .................................................................................................. 5-32 Table 5-13. Groundwater Budget Components for Water Year 2015 (AFY) ...................................... 5-34 Table 5-14. Root Zone Budget for Water Year 2015 .......................................................................... 5-34 Table 5-15. Land and Water Use Budget Components for Water Year 2015 ..................................... 5-34 Table 5-16. Future Scenario Water Year Types for Repeated and Adjusted Hydrology .................... 5-36 Table 5-17. Simulated Average Future Land and Water Use Budget Components (Units in Acre-Feet per Year, AFY) ................................................................................... 5-45 Table 5-18. Simulated Average Root Zone Budget Components (Area in acres, Flows in AFY) ........ 5-46 Table 5-19. Simulated Average Groundwater Budget Component Flows (Units in Acre-Feet per Year, AFY) ......................................................................................................................... 5-48 Table 5-20. Average Simulated Groundwater Budget Components Used to Develop the Sustainable Yield of the ECC Subbasin ............................................................................. 5-54 Table 5-21. Simulated Groundwater Budget Components for GSAs in the ECC Subbasin for Base Period, WY 1997-2018 (Units are in Acre-Feet per Year, AFY) ........................................ 5-57 Table 5-22. Simulated Future Scenario Groundwater Budgets for Individual GSAs........................... 5-59 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-iii LIST OF FIGURES Figure 5-1a Model Grid and Node Refinement………………………………………………………………………………..5-8 Figure 5-1b Model Grid and Node Refinement…………………………………………………………..…………………….5-9 Figure 5-1c Model Nodes for Simulated Surface Water Features……………………………….………………….5-10 Figure 5-2 Future Urban Footprint (2026) and Land Use (2016)…………………………………………………..5-13 Figure 5-3 Groundwater Budget for East Contra Costa Subbasin Historical Calibration Period (1997-2018)..………………………………………………………………………………………………………………5-22 Figure 5-4 Groundwater Budget Inflow Components East Contra Costa Subbasin Base Period (1997-2018)...……………………………………………………………………………………………………………..5-24 Figure 5-5 Groundwater Budget Outflow Components East Contra Costa Subbasin Base Period (1997-2018).…………………………………………………………………………………………………….5-26 Figure 5-6 Groundwater Budget Storage Component East Contra Costa Subbasin Base Period (1997-2018)..………………………………………………………………………………………………………………5-28 Figure 5-7 Average Simulated Change in Storage by Water Year Type………………………………………….5-31 Figure 5-8 Average Groundwater Budget Components During the Base Period (1997-2018) by Water Type…………………………………………………………………………………………………………….5-33 Figure 5-9 Groundwater Budget for East Contra Costa Subbasin Future Land Use Scenario (1997-2068)………………………………………………………………………………………………………………..5-38 Figure 5-10 Groundwater Budget for East Contra Subbasin Future Land Use and Climate Change Scenario (1997-2068)…………………………………………………………………………5-39 Figure 5-11 Groundwater Budget for East Contra Subbasin Future Land Use and Sea Level Rise Scenario (1997-2068)………………………………………………………………………………….5-40 Figure 5-12 Groundwater Budget for East Contra Costa Subbasin Future Land Use, Climate Change, and Sea Level Rise Scenario (1997-2068)………………………………………………………..5-41 Figure 5-13 Groundwater Budget for East Contra Costa Subbasin Future Land Use and Climate Change (Wet) Scenario (1997-2068)………………………………………………………………….………..5-42 Figure 5-14 Groundwater Budget for East Contra Costa Subbasin Future Land use and Climate Change (Dry) Scenario (1997-2068)…………………………………………………………….……………...5-43 Figure 5-15 Subset of Calibration Plots from ECCSim…………………………………………………………………..…5-50 Figure 5-16 Simulated vs. Observed Groundwater Elevation By Layer…………………………………………….5-51 Figure 5-17 Simulated Cumulative Change in Groundwater Storage for Sustainable Yield Development ……………………………………………………………………………………….…………….5-55 Figure 5-18 Average Water Budget Components During the Historical Calibration Period (1997-2018)……………………………………………………………………………..………………………5-58 APPENDICES Appendix 5a Model Documentation EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-1 5. WATER BUDGET (§ 354.18) The water budget developed for the East Contra Costa Subbasin provides an accounting and assessment of the total annual volume of groundwater and surface water entering and leaving the Subbasin, including historical, current and projected water budget conditions, and the change in the volume of water stored. The water budgets for various future scenarios were quantified in accordance with DWR Best Management Practices guidelines for water budgets and modeling (DWR, 2016). East Contra Costa Subbasin Hydrologic Base Period 1 In accordance with GSP regulations and BMP guidelines, a base period was selected in order to reduce bias that might result from the selection of an overly wet or dry period, while accounting for changes in other conditions including land use and water demands. The historical base period must include a minimum of 10 years of surface water supply information, with 30 years recommended. The current base period must also include a representative recent one-year period; and the projected base period must include a minimum of 50 years of historical precipitation, evapotranspiration, and streamflow data. The historical, current, and projected water budget base periods were selected on a water year(WY) basis considering the following criteria: 1. Cumulative departure from average annual precipitation curves2; 2. San Joaquin Valley water year type3; 3. Inclusion of both wet and dry periods; 4. Antecedent dry conditions4; 5. Adequate data availability; and 6. Inclusion of current hydrologic, cultural, and water management conditions in the Subbasin. For the ECC Subbasin, a 22-year historical water budget base period of water years 1997-2018 was selected. The cumulative departure from mean annual precipitation curve provided an efficient way to analyze historic and current water conditions in the Subbasin. The cumulative departure curve is presented in Figure 5-1 Cumulative Departure from Mean Annual Precipitation and illustrates that the 1 A base period is representative of long-term conditions in the basin that reflects natural variations in precipitation and is not biased by being overly wet. 2 Cumulative departure curves are used to show patterns of precipitation or streamflow to characterize long-term hydrology including drier and wetter periods relative to the mean annual precipitation. Negative, or downward, slopes indicate dry patterns while positive or upward slopes indicate wetter periods relative to the mean. Flatter portions of the cumulative departure curve indicate stable, or average, conditions during that period. 3 Water year types are used for the development of historical and current water budgets as available from the Department of Water Resources. The dataset applicable to the ECC Subbasin is based on the San Joaquin Valley Index from which precipitation is derived for various conditions (i.e., wet, above normal, below normal, dry, critical); DWR (2021). 4 Selecting a base period with antecedent (or prior) dry conditions minimizes the effects of the unsaturated zone on basin-wide groundwater budgets. The volume of water in the unsaturated zone is difficult to determine on the scale of a groundwater basin, so it is best to select a base period that has relatively dry conditions antecedent to the beginning of the study or base period. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-2 selected base period (1997 to 2018) includes both wet and dry periods, along with dry conditions prior to the beginning of the start of the base period and represents current land use and water practices. The selected base period also has the best collection of groundwater and surface water data. Groundwater pumping records from entities within the Subbasin are typically not available prior to the 1990s, and the quality and quantity of specific groundwater data improves closer to the present. Surface water data is also available during the selected base period through public databases, and greatly improves in quality and quantity to the present, particularly for surface water deliveries. Summary of Water Year 2015 Hydrologic Conditions For the current water budget, the water year 2015 is used. This year is appropriate because it represents current land use in years with available data at the initiation of SGMA data collection and analysis work. Hydrologic conditions in water year 2015 including precipitation5, evapotranspiration 6, groundwater levels 7, and surface water flows 8 can also be used to represent current conditions. Projected 50-Year Hydrology (§354.18(c)(3)) The projected 50-year hydrology was developed using average historical precipitation, evapotranspiration, and streamflow information from the selected model base period as the baseline condition for estimating future hydrology. A numerical groundwater flow model was used to simulate projected future scenarios including under expected changes in urban growth9 (land use), and anticipated climate change10 and sea level rise 11 (hydrology). Model selection is described in Section 5.1.5 and is referred to as the East Contra Costa Groundwater-Surface Water Simulation Model, or ECCSim. Model simulation scenarios are run from WY 2019 through 2068 (50 years) beginning on October 1, 2018, and ending September 30, 2068, at a monthly time step. The projected water demand uses the most recent land use at the beginning of the scenario and follows urban growth patterns from IRWMP, UWMP, or Contra Costa LAFCO documents. For future scenarios, evapotranspiration, precipitation, and streamflow are varied using DWR’s SGMA Guidance for Climate Change Data Use During Groundwater Sustainability Plan Development document (DWR, 2018). DWR provides adjustments for different climate change scenarios. DWR summarizes the various model outputs and respective timelines, which indicates that the most recent fifty-year period of common simulation periods is 1954-2003. Therefore, the historic simulation period selected to apply climatic adjustments over a 50-year period for ECC is 1954-2003. The adjustment factors for precipitation and reference evapotranspiration were gridded over the entire state and provided by DWR. Sea level rise is also considered and incorporated into the future scenarios using DWR’s guidance documentation that provides median predicted values for the years 2030 and 2070 that translate to about 0.5 to 1.4 feet of 5 Precipitation is water released from clouds in the form of rain, freezing rain, sleet, snow, or hail. 6 Evapotranspiration is the sum of evaporation from the land surface plus transpiration from plants. 7 Groundwater level is the depth or elevation above or below sea level at which the surface of groundwater stands. 8 Surface water flow is the continuous movement of water in runoff or open channels 9 Urban growth is the rate at which the population of an urban area increases. 10 Climate change is a long-term change in the average weather patterns that have come to define Earth's local, regional, and global climates. 11 Sea level rise is an increase in the level of the world’s oceans due to the effects of global warming. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-3 sea-level rise, respectively 12. The combination of land use, climate change, and sea level rise is also simulated for the projected 50-year hydrology simulations. The water demand uncertainty associated with projected changes in local land use planning, population growth, and climate is addressed by evaluating the groundwater budget components using all of the various future model scenarios. Projected surface water supply uses the most recent water supply information as the baseline condition for estimating future surface water supply. The surface water supply availability and reliability are a function of the historical surface water supply, which has been generally stable over the model Base Period where records of diversions are available. While some users in the Subbasin rely wholly on groundwater as a source of supply (e.g., individual domestic well owners and small domestic water systems 13), large-scale users (e.g., municipal water systems and agriculture) are projected to use groundwater to supplement surface water when insufficient amounts are available. Water Budget Framework The water budget framework for the ECC Subbasin accounts for the total annual volumes of groundwater and surface water entering and leaving the subbasin. These volumes are described as inflows and outflows as described below. Surface Water Inflows and Outflows There are many surface water bodies that comprise the surface water system in the ECC basin, including Marsh Creek, Clifton Court Forebay, Franks Tract, Old River, San Joaquin River, Big Break, and other Delta features. Surface water inflows and outflows are summarized below: o Surface water inflows into the Subbasin as streamflow occur via Marsh Creek, San Joaquin River, and Old River; o Surface water inflows to the Subbasin from outside through conveyance facilities via a series of sloughs and canals off of Old River and San Joaquin River; o Surface water outflows from the Subbasin as runoff and groundwater discharge to surface water bodies including the Delta. Groundwater Inflows and Outflows Groundwater flows are summarized below for the Subbasin: o Groundwater inflows to the Subbasin from groundwater recharge and subsurface inflows along Subbasin boundaries; o Groundwater outflows from the Subbasin via subsurface lateral flow; and 12 Department of Water Resources, Guidance for Climate Change Data Use During Groundwater Sustainability Plan Development, July 2018. 13 In Contra Costa County, a small water system is defined as a Public Water System (CA Health and Safety Code §11625) serving domestic purposes for two to one-hundred ninety-nine connections (County Ordinance Code §414- 4.221). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-4 o Groundwater outflows due to evapotranspiration, subsurface drains, and groundwater pumping. Summary of Water Budget Components All water budget components and sources of data used with the ECCSim model are summarized in Table 5-1, including a) general components included in every water use sector water budget and b) specific components unique to individual water use sectors. Table 5-1. Water Budget Components Component Category Data Type Calculation Or Estimation Method Precipitation Inflow Meteorological Data C2VSim and Antioch/Brentwood precipitation stations Subsurface Lateral Flow Inflow/Outflow Groundwater Data ECCSim Surface Water Deliveries Inflow Surface Water Data Reported by historical water rights and statements of diversion (eWRIMS); estimated based on records when unavailable. Evapotranspiration (ET) of Applied Water Outflow Meteorological Data, Crop Water Use Estimated by the Integrated Water Flow Model Demand Calculator (IDC) component of the ECCSim model Evapotranspiration (ET) of Precipitation Outflow Meteorological Data, Crop Water Use Estimated by the Integrated Water Flow Model Demand Calculator (IDC) component of the ECCSim model Runoff Outflow Surface Data Estimated by the Integrated Water Flow Model Demand Calculator (IDC) component of the ECCSim model Groundwater Pumping Outflow Groundwater Data Pumping records for municipalities and closure term for domestic/irrigation pumping (pumping records provided by Brentwood, ECCID, Town of Discovery Bay, and Diablo Water District (Oakley). Drains Outflow Groundwater Data Drain elevations and extent based on historic maps and data requests to GSAs Change in Storage Inflow/Outflow Groundwater Data Estimated using analytical methods and numerical modeling (ECCSim) techniques. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-5 Groundwater/Surface Water Flow Model Evaluation of Existing Integrated Hydrologic Models The development of the East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) involved starting with and evaluating the U.S. Geological Survey’s Central Valley Hydrologic Model (CVHM) and the beta version (released 5/1/2018) of DWR’s fine-grid version of the California Central Valley Groundwater-Surface Water Flow Model (C2VSim-FG Beta2). Both publicly available models were evaluated for suitability in the preparation of the ECC Subbasin GSP. The CVHM model was published in 2009, but the simulation period ends in September 2003. C2VSim-FG Beta2 simulated to September 2015. Neither of these models were current at the time of ECCSim development, and they lacked important simulated surface water features specific to the ECC area due to their application for more regional analyses. Additionally, neither existing model had sufficient calibration points in the ECC Subbasin. Since the C2VSim model’s simulation period more closely matched the end of the model Base Period (i.e., water years 1997-2018), and that the aquifer parameters in the ECC domain were more similar, the C2VSim-fine grid beta version was selected for use as a basis for the ECC Subbasin model. This led to extracting a local model domain and conducting local refinements to the model structure (e.g., nodes, elements) and modifying or replacing inputs as needed to accurately simulate local conditions in the Subbasin within the model domain. C2VSim-FG Beta2 utilizes the most current version of the Integrated Water Flow Model (IWFM) code available at the time of the ECCSim development. IWFM and C2VSim-FG Beta2 were selected as the modeling platform, in part, due to: 1. the versatility in simulating crop-water demands in the predominantly agricultural setting of the subbasins, 2. groundwater surface-water interaction, 3. the existing hydrologic inputs existing in the model for the time period through the end of water year 2015, and 4. the ability to customize the existing C2VSim-FG Beta2 model to be more representative of local conditions in the area of the ECC Subbasin. 5. ECCSim was refined from C2VSim-FG Beta2 and calibrated to a diverse set of available historical data using industry standard techniques. Selection and Refinements to Model Platform The modeling code and platform utilized for ECCSim are described below. As required by GSP regulations, the selected model code is in the public domain (see link below or request data from groundwaterinfo@dcd.cccounty.us). The decision to select the model codes for the ECCSim was based on providing the Subbasin with a modeling tool that can be used for GSP development and future planning with sufficient representation of local conditions, while utilizing to the extent possible, other available modeling tools, including regional models. Several refinements were performed to the C2VSim-FG Beta2 model during development of ECCSim. These refinements produce a clearer, more comprehensive water budget model for future planning analyses and include the following: EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-6 • Model grid (node and element) refinements (Figure 5-1a) o The ECCSim grid contains 1,097 nodes and 1,209 elements that align with GSA boundaries, surface water features, and delta island geometry. • Model subregion refinements (Figure 5-1b and Table 5-2) o The ECCSim model domain groups elements into subregions to assist in the summarization of model results and development of water budgets. o The ECCSim has 34 subregions; 19 of which are in the ECC Subbasin. • Surface water bodies (Figure 5-1c) o CVHM and C2VSim-FG Beta2 only simulated the San Joaquin River and the Delta; ECCSim simulates Marsh Creek, Old River, Middle River, San Joaquin River, Big Break, Franks Tract, and Clifton Court Forebay. • Model layers o The C2VSim-FG Beta2 model layering was adapted for ECCSim purposes to better represent the hydrogeological conceptual model (HCM) of the aquifer system through model layering. o The ECCSim model includes four aquifer layers (Shallow Aquifer in layers 1 and 2; Deep Aquifer in layers 3 and 4). • Land use refinements o Due to changes in the model element and node configurations, the land use was updated and refined relative to C2VSim-FG Beta2 using land use surveys from 1995, 2014, and 2016 (DWR). The major land use types include irrigated agriculture crops, riparian and native vegetation, and urban. • Aquifer parameter refinements o Due to differences in model layering and the more extensive calibration associated with ECCSim, aquifer parameters were refined by incorporating information about depositional environments for subsurface materials such as Alluvial Plain, Delta Islands, Fluvial Plain, and Marginal Delta Dune which are part of the basin setting (see Section 3). • Model boundary conditions o General head boundaries were developed along the northern, eastern, and southern borders based on interpreted groundwater elevations from C2VSimFG Beta2 and calculated horizontal conductivity, distance between boundary nodes, aquifer layer thickness, and the distance from the model boundary. • Groundwater pumping o Pumping within ECCSim is simulated using a combination of individual wells with assigned pumping and elemental pumping14. 14 The IWFM modeling platform allows for prescribed groundwater pumping from individual wells as time-series extraction data. Alternatively, for wells of known construction, water use type, and location, IWFM can estimate the amount of monthly pumping necessary to fulfill the water demands within each water balance subregion. These wells are assigned an extraction amount by the model itself, to the particular model element they are located within, and are therefore considered to be “elemental pumping”. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-7 o Wells serving municipalities for which GSAs provided monthly pumping records were simulated directly. o Elemental pumping is calculated internally by the Integrated Water Flow Model Demand Calculator component of the ECCSim model to meet both agricultural and domestic/urban demands after available surface water deliveries have been accounted for. o The distribution of pumping by layer was modified based on well construction information in DWR’s database of Well Completion Reports for wells within the model domain. • Tile drains o Tile drains were incorporated in ECCSim based on historic drain maps and direct information from GSAs. o Information from GSAs indicate that tile drains occur at 5 to 8 feet below land surface. • Surface water deliveries o Surface water deliveries for ECCSim were assigned as diversions from specified stream nodes with an assigned delivery destination (water balance subregion), and amounts were based on data received from individual GSAs as well as the State Water Resources Control Board Electronic Water Rights Information Management System (eWRIMS) database. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-8 Figure 5-1a EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-9 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-10 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-11 Table 5-2 Water Balance Subregions Subregion Subbasin/Basin GSA Area 1 East Contra Costa City of Antioch GSA Antioch 2 East Contra Costa Diablo Water District GSA Big Break 3 Oakley 4 East Contra Costa County of Contra Costa GSA Jersey Island 5 Bradford Island 6 Webb Tract 7 Franks Tract 8 Bethel Island 9 Holland Tract 10 Knightsen 11 Orwood 12 South Discovery Bay 13 Clifton Court Forebay 14 Coney Island 15 South Clifton Court Forebay 16 East Contra Costa City of Brentwood GSA Brentwood 17 East Contra Costa East Contra Costa Irrigation District GSA ECCID 18 East Contra Costa Discovery Bay Community Services District GSA Town of Discovery Bay 19 East Contra Costa Byron-Bethany Irrigation District GSA – East Contra Costa BBID North (Byron Division) 20 Tracy Byron-Bethany Irrigation District GSA - Tracy BBID South (Bethany Division) 21 BBID Mountain House Division 22 Tracy County of San Joaquin GSA – Tracy Hammer Island 23 Union Island 24 Victoria Island 25 Woodward Island 26 Bacon Island 27 Mandeville Island 28 Eastern San Joaquin Central Delta Water Agency GSA Venice Island 29 Bouldin Island 30 Solano Reclamation District No. 317 GSA Andrus Island 31 Solano County of Sacramento GSA - Solano Twitchell Island 32 Sherman Island 33 Kimball Island 34 Pittsburg Plain Not Applicable Pittsburg EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-12 Projected (Future) Model Scenario(s) The projected future model scenarios involve simulating conditions in the ECC Subbasin from water year 2019 through water year 2068. Various future projected model scenarios were developed for this GSP document: 1) Future Land Use Change – this model scenario incorporates anticipated urban growth by 2026, as provided by Contra Costa County, with repeated hydrology; 2) Future Climate Change – this model scenario utilizes the land use change (urban growth) as well as the 2070 Central Tendency climate change adjustment factors to hydrologic conditions including evapotranspiration (ET), precipitation, surface water levels, and diversions; 3) Future Sea Level Rise – this model scenario utilizes the land use change (urban growth) in addition to incremental sea level rise on the northern surface water bodies in the ECCSim model domain, while using repeated hydrology; 4) Future Climate Change Plus Sea Level Rise – this model scenario incorporates land use change (urban growth), as well as both climate change and sea level rise adjustments to the hydrology; 5) Sustainable Yield – this model scenario incorporates land use change (urban growth) but was developed to increase groundwater pumping to determine an estimated sustainable yield of the ECC Subbasin. The future land use scenario results in a larger urban footprint (Figure 5-2) based on planning information from the County 15. Hydrology including evapotranspiration, precipitation, and surface water levels were adapted from values from previous years using the pattern of water year type associated with the historic 50-year time period (1954 to 2003). Development of the future climate change hydrology conditions inputs are based on DWR’s Guidance for Climate Change Data Use During Groundwater Sustainability Plan Development document (DWR, 2018). DWR provides climate change adjustment values for climate data, streamflow data, and sea-level rise information. These adjustments are applied to historical hydrology to achieve a future hydrologic period of 50 years that are representative of hydrology potentially occurring in the future. The 2070 central tendency climate change scenario was selected for this future climate scenario analysis. Regarding sea level rise, DWR’s Guidance Document mentions that sea-level rise estimates by the National Research Council (NRC) provide two values of expected sea-level rise as median predicted values for the years 2030 and 2070. These two values are 15 and 45 centimeters, respectively, or about 0.5 to 1.4 feet of sea-level rise. Values were assigned on an annual basis through linear interpolation of these projections. 15 Contra Costa County provided a GIS shapefile representing the 2030 urban footprint via email (pers. comm. Ryan Hernandez, February 18, 2021). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-13 Figure 5–2 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - WATER BUDGET LSCE 5-14 Subbasin Water Budget Results (§354.18(a) to (d)) This section includes a description of the accounting and assessment of the total annual volume of groundwater and surface water entering and leaving the basin, including historical, current and projected water budget conditions, and the change in the volume of water stored. Inflows and Outflows Entering and Leaving the Basin The various water budget components of inflows and outflows including surface water entering and leaving the basin occurs through various locations along the border of the ECC Subbasin. Using the integrated groundwater and surface water model, ECCSim, it is possible to quantify the amount of water entering and exiting the basin via various water budget components. Groundwater inflows include subsurface groundwater inflow and infiltration of precipitation, applied water, and surface water systems (e.g., streams, rivers, canals, and conveyance systems). Groundwater outflows include evapotranspiration, groundwater extraction (pumping), groundwater discharge to surface water sources, and subsurface groundwater outflow. Water budget components can be grouped or categorized into detailed water budget accounting centers to represent different mechanisms within the Subbasin: 1. land and water use activities (such as supply and demand for urban and agricultural land uses), 2. root zone activities (such as agricultural applied water, precipitation, evapotranspiration, and percolation), as well as 3. groundwater activities (such as surface water/groundwater interaction, tile drain flows, groundwater pumping, recharge via deep percolation, small watershed contributions, and subsurface lateral flow). Water budget components for these three accounting centers are qualitatively described in Table 5-3 below. Each water budget component listed in in the table is calculated on a monthly basis using ECCSim and summarized annually for each water year. The quantitative values are presented in both graphical and tabular form for the model Base Period (water years 1997 to 2018) depending on the detailed water budget accounting center. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-15 Table 5-3. Water Budget Accounting Components Simulated Using ECCSim Simulated Water Budget Accounting Center Detailed Component Category Description Land and Water Use (Agricultural and urban land use sectors) Surface Water Deliveries Inflow Deliveries from conveyance systems to customers; includes diversions and surface water rights. This water component is separated for urban and agricultural water uses. Groundwater Extraction Inflow Groundwater pumping to meet water demands. This water component is separated for urban and agricultural water uses. Urban Demand Outflow Water demand associated with urban land use. Agricultural Demand Outflow Water demand associated with agricultural land use. Root Zone (Agricultural, urban, and native/riparian vegetation land use sectors) Agricultural Applied Water Inflow Applied water to satisfy agricultural water demand (may come from surface water deliveries and/or groundwater extraction). Agricultural Effective Precipitation Inflow Precipitation on agricultural land that helps meet agricultural demand. Agricultural Evapotranspiration Outflow Evapotranspiration associated with the variety of crops within the Subbasin. Agricultural Percolation Outflow Applied water and precipitation on agricultural land that is in excess of the evapotranspiration requirement and passes through the root zone to reach the groundwater water table. Urban Applied Water Inflow Water applied to landscaping within urban land use features (can come from surface water deliveries and/or groundwater pumping). Urban Effective Precipitation Inflow Water from precipitation that helps support outdoor urban land use demands such as landscaping. Urban Evapotranspiration Outflow Evapotranspiration associated with outdoor urban water demand. Urban Percolation Outflow Applied water and precipitation on urban land that is in excess of the evapotranspiration requirement and passes through the root zone to reach the groundwater water table. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-16 Simulated Water Budget Accounting Center Detailed Component Category Description Native/Riparian Vegetation Effective Precipitation Inflow Water from precipitation that supports native and riparian vegetation. Native/Riparian Vegetation Evapotranspiration Outflow Evapotranspiration associated with native and riparian vegetation within the Subbasin. Native/Riparian Vegetation Percolation Outflow Precipitation on native/riparian vegetation that is in excess of the evapotranspiration requirement and passes through the root zone to reach the groundwater water table. Groundwater (all land use sectors including urban, agricultural, and native/riparian vegetation) Groundwater flow to/from Surface Water Features Inflow or Outflow This is the surface water/groundwater interaction component that represents stream leakage (in the case of losing stream conditions) or groundwater contributions to surface water (during gaining stream conditions). Streams include Marsh Creek, Old River, and the San Joaquin River. For the ECC Subbasin, this component also includes surface water interaction with groundwater associated with delta island surface water features, such as Big Break and Franks Tract, but also Clifton Court Forebay to the south. Drains Outflow Tile drains historically and currently used to lower the water table in certain areas within the Subbasin. Diversion Recoverable Loss Inflow This water budget component represents leakage of surface water through conveyances within the Subbasin. Small Watershed Contributions Inflow Small watersheds along the western boundary of the Subbasin contribute some water to the groundwater system. Recharge via Deep Percolation Inflow Water that travels vertically through the root zone to reach the water table and enter the groundwater system. Groundwater Extraction (Pumping) Outflow Pumping of groundwater to satisfy urban and agricultural water demands. Subsurface Inflow and Outflow Inflow or Outflow Subsurface lateral flow into or out of the Subbasin. Groundwater Storage Inflow minus Outflow = Change in Storage This component is used to determine the change in aquifer storage over time and can help determine if a basin is in balance, is full, or is in overdraft. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5- WATER BUDGET LSCE 5-17 The first simulated water budget accounting center, for land and water use, utilizes well pumping information developed for the GSP by the GSAs within the ECC Subbasin. Elemental groundwater pumping (where pumping rates are not directly input) is invoked when surface water deliveries (specified for urban, agricultural, or both land uses) are insufficient to meet water demands. Elemental groundwater pumping is based on well completion report (WCR) records for which well depths and well types are known or estimated. Surface water deliveries previously developed for the GSP as reported by GSAs within ECC Subbasin were supplemented by individual water rights adapted from eWRIMS. Table 5-4 below shows the simulated land and water use for the Subbasin, as well as the average land and water use amounts associated with the model Base Period (water years 1997-2018). ECCSim simulates the majority of agricultural and urban demand being satisfied by surface water deliveries. The simulation indicates that during some years there are small amounts of surplus water supplies (agricultural or urban demand shortage term is negative), and other years there are small amounts of water demand shortage. The simulated root zone budget details the movement of different water sources within agricultural, urban, and native/riparian vegetation land use sectors, the land surface, and the underlying groundwater aquifer system. Using the ECCSim monthly timestep simulated outputs, these components are summarized for water years during the model Base Period (water years 1997-2018). The annual values of simulated applied water, effective precipitation, evapotranspiration, and percolation that occur in the root zone are provided in Table 5-5 for agricultural, urban, and native/riparian vegetation land uses. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5- WATER BUDGET LSCE 5-18 Table 5-4. Simulated Land and Water Use Budget Components for Base Period, WY 1997-2018 (Units in Acre-Feet per Year, AFY) Water Year Ag. Supply Requirement Ag. Pumping Ag. Deliveries Ag. Demand Shortage Urban Supply Requirement Urban Pumping Urban Deliveries Urban Water Demand Shortage 1997 173,948 35,436 138,553 -41 24,246 7,470 17,102 -325 1998 139,759 29,767 110,091 -99 25,303 8,980 15,356 967 1999 164,080 32,735 130,615 730 26,360 8,176 17,085 1,100 2000 166,727 34,359 132,094 275 27,393 7,612 18,403 1,377 2001 173,716 39,147 132,851 1,719 28,425 7,713 19,969 743 2002 174,548 42,841 131,694 13 29,458 8,794 20,389 274 2003 167,222 41,496 125,794 -68 30,490 9,349 20,583 558 2004 174,627 41,093 133,654 -120 31,523 9,798 21,708 17 2005 150,977 35,293 115,679 5 32,555 10,123 21,844 588 2006 162,067 42,915 119,338 -187 33,588 10,830 21,565 1,193 2007 182,393 42,027 139,957 410 34,620 10,213 24,181 226 2008 186,743 47,873 138,754 116 35,303 10,378 23,183 1,743 2009 174,105 45,618 129,367 -880 32,658 10,024 23,112 -477 2010 155,735 37,990 117,843 -98 33,084 10,080 22,931 73 2011 147,850 35,498 112,640 -289 33,509 9,467 23,847 195 2012 174,046 43,108 128,765 2,173 33,935 9,088 24,383 465 2013 191,902 21,655 169,710 537 33,982 10,849 21,663 1,470 2014 194,431 31,298 163,386 -253 34,407 11,017 22,070 1,320 2015 166,604 39,747 127,011 -155 25,924 7,893 17,768 264 2016 172,588 35,734 136,356 498 26,607 6,439 20,495 -327 2017 156,725 35,233 121,314 178 26,724 7,174 19,836 -285 2018 159,944 32,947 127,004 -7 26,724 6,733 20,170 -178 Average 168,670 37,446 131,021 203 30,310 9,009 20,802 499 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5- WATER BUDGET LSCE 5-19 Table 5-5. Simulated Root Zone Budget Components for Base Period, WY 1997-2018 (Units in Acre-Feet per Year, AFY) Water Year Agricultural Land Use Area (Acres) Ag. Precip. (+) Ag. Applied Water (+) Ag. Et (-) Ag. Perc. (-) Urban Land Use Area (Acres) Urban Precip (+) Urban Applied Water (+) Urban Et (-) Urban Perc. (-) Native & Riparian Veg. Land Use Area (Acres) Native & Riparian Veg. Precip (+) Native & Riparian Veg. Et (-) Native & Riparian Veg. Perc. (-) 1997 50,035 67,815 173,990 179,806 61,747 19,396 25,436 24,571 16,831 33,165 39,719 52,569 36,907 15,679 1998 50,035 113,418 139,858 170,867 82,546 19,396 44,125 24,336 21,809 46,600 39,719 88,097 59,334 28,389 1999 50,035 51,736 163,350 173,000 41,955 19,396 19,096 25,260 18,297 26,083 39,719 39,688 34,648 5,331 2000 50,035 67,803 166,453 179,642 54,775 19,396 25,724 26,016 19,556 32,171 39,719 52,511 41,042 11,453 2001 50,035 50,060 171,997 182,790 39,257 19,396 18,350 27,682 19,440 26,596 39,719 39,294 35,012 4,296 2002 50,035 53,812 174,535 181,778 46,484 19,396 20,229 29,184 19,049 30,375 39,719 42,216 34,929 7,464 2003 50,035 60,586 167,289 179,842 48,083 19,396 22,172 29,932 20,183 31,909 39,719 47,479 38,591 8,699 2004 50,035 53,734 174,747 181,061 47,444 19,396 20,049 31,506 18,722 32,802 39,719 41,940 33,746 8,079 2005 50,035 89,122 150,972 177,575 62,718 19,396 35,331 31,967 24,160 43,133 39,719 69,438 54,484 15,051 2006 50,035 82,988 162,253 183,310 61,892 19,396 32,715 32,395 23,020 42,103 39,719 64,515 50,055 14,569 2007 50,035 34,448 181,984 180,444 36,028 19,396 12,766 34,394 19,289 27,840 39,719 26,252 23,110 3,194 2008 50,035 42,795 186,627 183,910 45,315 19,396 15,828 33,560 18,248 31,192 39,719 33,414 26,749 6,813 2009 50,035 51,320 174,985 185,103 41,132 19,396 21,119 33,135 21,764 32,480 39,719 40,184 34,840 5,031 2010 50,035 66,927 155,833 175,730 47,212 19,396 27,654 33,011 23,930 36,728 39,719 52,014 45,226 6,928 2011 50,035 81,377 148,138 173,735 55,812 19,396 31,783 33,314 24,446 40,655 39,719 63,282 51,093 12,048 2012 50,035 41,388 171,873 178,126 35,115 19,396 16,672 33,470 21,315 28,821 39,719 31,933 28,907 3,199 2013 41,730 39,117 191,365 181,222 48,381 21,454 19,479 32,512 22,012 35,438 45,965 42,132 33,445 6,708 2014 41,730 29,643 194,684 183,458 40,737 21,454 15,859 33,087 20,758 28,235 45,965 32,179 29,069 3,252 2015 41,329 42,671 166,759 163,801 46,733 22,585 24,714 25,660 18,676 32,463 45,236 46,561 35,228 11,194 2016 41,329 20,731 172,090 161,966 30,947 22,585 11,211 26,934 16,102 22,038 45,236 21,969 19,246 2,789 2017 41,329 63,558 156,547 168,560 51,785 22,585 33,834 27,009 21,803 39,012 45,236 68,607 53,525 14,773 2018 41,329 41,399 159,951 165,665 35,596 22,585 21,522 26,903 20,655 27,783 45,236 44,783 39,796 5,051 Average 47,697 56,657 168,467 176,881 48,259 20,163 23,439 29,811 20,458 33,074 41,290 47,321 38,135 9,090 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-20 The simulated groundwater budget embodies the movement of water within the groundwater aquifer. Using the ECCSim monthly timestep simulated outputs, these components are summarized for water years during the model Base Period (water years 1997-2018). Simulated values of groundwater leaving the subsurface via drains, the movement, or exchange, of water between surface water features, contributions from small watersheds in the western portion of the Subbasin, contributions from unlined conveyances (diversion recoverable loss), groundwater leaving the aquifer via groundwater extraction (pumping), and subsurface lateral flow are presented in Table 5-6. These groundwater budget terms provide the inflows and outflows from which the change in storage can be calculated (inflow minus outflow = change in storage). The annual changes in groundwater storage and the cumulative change in groundwater storage are also presented in Table 5-6. ECC Subbasin Water Balance Generally, water leaves the groundwater system within ECC Subbasin through drains, groundwater extraction (pumping), and through subsurface lateral flow (leaving the subbasin). Water enters the groundwater body via surface water features, deep percolation (recharge), small watershed contributions, and diversion recoverable loss. The change in storage term along with the cumulative change in storage term indicate that the ECC Subbasin is in balance. If the subbasin was depleting groundwater storage, or in overdraft, the change in storage and the cumulative change in storage would be negative and growing more negative over time. The simulation results indicate that this is not the case in the ECC Subbasin. The simulated groundwater budget timeseries components are plotted along with the cumulative change in storage in order to illustrate the proportions of the various components and to see that the basin is operating within its sustainable yield during the model Base Period (water year 1997-2018) (Figure 5-3). The following sections discuss groundwater inflows and outflows in the ECC Subbasin and the resultant changes in storage. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-21 Table 5-6. Simulated Groundwater Budget Components for Base Period, WY 1997-2018 (Units in Acre-Feet per Year, AFY) WATER YEAR DRAINS SURFACE WATER FEATURES DEEP PERCOLATION SMALL WATERSHED BASEFLOW SMALL WATERSHED PERCOLATION DIVERSION RECOVERABLE LOSS PUMPING NET SUBSURFACE FLOW NET STORAGE CHANGE CUMULATIVE CHANGE IN STORAGE 1997 -91,890 9,843 109,296 1,417 2,499 17,688 -42,906 -13,738 -8,095 0 1998 -116,071 9,481 184,027 2,320 26,702 14,255 -38,747 -15,817 65,310 57,214 1999 -77,389 10,075 58,923 1,617 110 16,784 -40,910 -12,461 -43,556 13,659 2000 -83,593 17,343 89,128 1,340 85 17,102 -41,971 -11,243 -12,012 1,647 2001 -68,650 13,188 61,586 1,160 0 17,366 -46,860 -9,614 -31,853 -30,206 2002 -70,279 22,222 83,420 1,034 0 17,282 -51,636 -9,302 -7,272 -37,478 2003 -69,411 13,556 83,001 949 0 16,634 -50,844 -8,204 -14,293 -51,771 2004 -69,792 22,056 92,525 853 0 17,655 -50,891 -8,218 4,180 -47,591 2005 -84,609 14,873 130,479 1,102 4,232 15,628 -45,417 -10,363 25,834 -21,757 2006 -82,001 13,348 124,671 1,172 13,094 16,012 -53,745 -9,590 22,896 1,139 2007 -62,782 13,268 56,414 965 0 18,652 -52,240 -7,426 -33,147 -32,008 2008 -67,260 23,472 80,468 860 0 18,402 -58,251 -7,163 -9,469 -41,477 2009 -61,145 21,351 72,929 764 0 17,327 -55,642 -5,523 -9,933 -51,410 2010 -65,629 16,888 92,632 730 71 15,997 -48,070 -5,897 6,732 -44,679 2011 -73,746 11,409 113,521 850 2,717 15,510 -44,965 -6,426 18,871 -25,807 2012 -59,777 14,511 60,715 768 0 17,403 -52,196 -4,888 -23,432 -49,239 2013 -75,616 22,718 93,805 695 0 21,747 -32,504 -7,131 23,716 -25,523 2014 -101,955 19,546 66,114 612 0 21,075 -42,315 -7,768 -10,493 -36,016 2015 -66,415 24,787 93,960 572 0 16,452 -47,640 -8,290 13,411 -22,605 2016 -56,081 19,034 50,799 498 0 17,824 -42,173 -4,664 -14,713 -37,319 2017 -75,304 27,194 113,293 682 212 16,040 -42,407 -6,123 33,549 -3,769 2018 -66,938 30,852 69,813 518 0 16,724 -39,680 -7,161 5,216 1,447 Average -74,833 17,773 90,069 976 2,260 17,253 -46,455 -8,500 66 -21,980 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-22 -300,000 -200,000 -100,000 0 100,000 200,000 300,000 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Acre-feet (AFY)Water Year Net Flow to Storage Surface Water Features Drains Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Pumping Net Subsurface Flow Cumulative Change in Storage Groundwater Budget for East Contra Costa Subbasin Historical Calibration Period (1997-2018) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-3 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-23 Quantification of Groundwater Inflow The simulated groundwater budget described and quantified above indicate that the groundwater inflow components of the water budget include contributions from surface water features, deep percolation (recharge), small watershed contributions, and diversion recoverable loss (conveyance systems). These groundwater inflows are presented in tabular form in Table 5-7 and graphically in Figure 5-4. The largest groundwater inflow component is groundwater recharge through deep percolation. Deep percolation includes water reaching past the root zone to the water table from precipitation and excess applied water. Surface water features and diversion recoverable losses account for most of the remaining groundwater inflows, with a very small proportion contributed by the small watersheds to the west of the Subbasin. Table 5-7. Simulated Groundwater Inflow Components for Base Period, WY 1997-2018 (Units are in Acre-Feet per Year, AFY) Water Year Surface Water Features Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss 1997 9,843 109,296 1,417 2,499 17,688 1998 9,481 184,027 2,320 26,702 14,255 1999 10,075 58,923 1,617 110 16,784 2000 17,343 89,128 1,340 85 17,102 2001 13,188 61,586 1,160 0 17,366 2002 22,222 83,420 1,034 0 17,282 2003 13,556 83,001 949 0 16,634 2004 22,056 92,525 853 0 17,655 2005 14,873 130,479 1,102 4,232 15,628 2006 13,348 124,671 1,172 13,094 16,012 2007 13,268 56,414 965 0 18,652 2008 23,472 80,468 860 0 18,402 2009 21,351 72,929 764 0 17,327 2010 16,888 92,632 730 71 15,997 2011 11,409 113,521 850 2,717 15,510 2012 14,511 60,715 768 0 17,403 2013 22,718 93,805 695 0 21,747 2014 19,546 66,114 612 0 21,075 2015 24,787 93,960 572 0 16,452 2016 19,034 50,799 498 0 17,824 2017 27,194 113,293 682 212 16,040 2018 30,852 69,813 518 0 16,724 Average 17,773 90,069 976 2,260 17,253 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-24 0 50,000 100,000 150,000 200,000 250,000 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018Acre-feet (AFY)Water Year Surface Water Features Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Groundwater Budget Inflow Components East Contra Costa Subbasin Base Period (1997-2018) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-4 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 -WATER BUDGET LSCE 5-25 Quantification of Groundwater Outflow The simulated groundwater budget described and quantified in Section 5.6.3 indicates that the groundwater outflow components of the water budget consist of drains, groundwater pumping, and the net of subsurface lateral flow. These groundwater outflows are presented in tabular form in Table 5-8 and graphically in Figure 5-5. The largest groundwater outflow components are tile drains and pumping. Net subsurface lateral flow makes up the remaining groundwater outflow components. Table 5-8. Simulated Groundwater Outflows for Base Period, WY 1997-2018 (Units are in Acre-Feet per Year, AFY) Water Year Drains Pumping Net Subsurface Flow 1997 -91,890 -42,906 -13,738 1998 -116,071 -38,747 -15,817 1999 -77,389 -40,910 -12,461 2000 -83,593 -41,971 -11,243 2001 -68,650 -46,860 -9,614 2002 -70,279 -51,636 -9,302 2003 -69,411 -50,844 -8,204 2004 -69,792 -50,891 -8,218 2005 -84,609 -45,417 -10,363 2006 -82,001 -53,745 -9,590 2007 -62,782 -52,240 -7,426 2008 -67,260 -58,251 -7,163 2009 -61,145 -55,642 -5,523 2010 -65,629 -48,070 -5,897 2011 -73,746 -44,965 -6,426 2012 -59,777 -52,196 -4,888 2013 -75,616 -32,504 -7,131 2014 -101,955 -42,315 -7,768 2015 -66,415 -47,640 -8,290 2016 -56,081 -42,173 -4,664 2017 -75,304 -42,407 -6,123 2018 -66,938 -39,680 -7,161 Average -74,833 -46,455 -8,500 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-26 -180,000 -160,000 -140,000 -120,000 -100,000 -80,000 -60,000 -40,000 -20,000 0 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018Acre-feet (AFY)Water Year Drains Pumping Net Subsurface Flow Groundwater Budget Outflow Components East Contra Costa Subbasin Base Period (1997-2018) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-5 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-27 Change in Groundwater Storage Quantification of the change in annual groundwater storage is presented on a water year annual basis in Table 5-9. The net annual simulated change in storage and the cumulative change in storage are plotted graphically in Figure 5-6. This figure illustrates that the basin is not in overdraft over the model Base Period (water years 1997-2018). The average change in storage over this period is almost 70 AFY. This represents 0.05% of the groundwater inflows and outflows that comprise the groundwater budget for the groundwater Subbasin. Table 5-9. Simulated Groundwater Storage Component for Base Period,WY 1997-2018 (Units are in Acre-Feet per Year, AFY) Water Year Net Storage Change Cumulative Change In Storage 1997 -8,095 0 1998 65,310 57,214 1999 -43,556 13,659 2000 -12,012 1,647 2001 -31,853 -30,206 2002 -7,272 -37,478 2003 -14,293 -51,771 2004 4,180 -47,591 2005 25,834 -21,757 2006 22,896 1,139 2007 -33,147 -32,008 2008 -9,469 -41,477 2009 -9,933 -51,410 2010 6,732 -44,679 2011 18,871 -25,807 2012 -23,432 -49,239 2013 23,716 -25,523 2014 -10,493 -36,016 2015 13,411 -22,605 2016 -14,713 -37,319 2017 33,549 -3,769 2018 5,216 1,447 Average 66 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-28 -60,000 -40,000 -20,000 0 20,000 40,000 60,000 80,000 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018Acre-feet (AFY)Water Year Change in Storage Cumulative Change in Storage Groundwater Budget Storage Component East Contra Costa Subbasin Base Period (1997-2018) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-6 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-29 Water Year Types The ECCSim model Base Period of water years 1997 through 2018 contain wet, above normal, below normal, dry, and critical water year types (see Table 5-10 below). This modeling tool can be used to quantify water budget components according to water year types. Water budget components including the annual supply, demand, and change in groundwater storage can vary according to water year type. The simulated agricultural and urban supply and demand amounts are averaged for the various water year types that occur during the base period. These values are quantified in Table 5-11, and show that during drier years, agricultural and urban demand is higher than in wetter years. Due to the reliably available agricultural surface water deliveries in the Subbasin, surface water supplies have not been impacted during dry years. The reliability of surface water is reflected in the fact that over half the available supply is based on pre-1914 water rights owned by City of Antioch, ECCID, and BBID (see Section 4, Table 4-5). The change in groundwater storage can also be quantified based on water year type using the ECCSim tool. There is variability associated with groundwater storage changes that are not directly attributable to water year types. Changes in land use and supply mechanisms can have an impact on groundwater storage that may or may not have to do with the water year type. The box plot of average change in groundwater storage by water year type (Figure 5-7) shows that there is a general relationship of replenishing groundwater storage in wet years, and storage depletion in drier years. However, these relationships are not completely consistent. For example, in 1999 and 2000, storage depletion is indicated by the simulation (negative change in storage), despite being categorized as “above normal” water year type. Similarly, 2013 and 2015, which are considered “critical” water year types, have storage replenishment being simulated. These exceptions are due to the amount of surface water deliveries reported during those years and the amount of groundwater pumping needed to satisfy the demand. Table 5-10. Water Year Types During the Base Period Water Year Water Year Type Water Year Water Year Type 1997 W 2013 C 1998 W 2014 C 1999 AN 2015 C 2000 AN 2016 D 2001 D 2017 W 2002 D 2018 BN 2003 BN 2004 D W = Wet 2005 W 2006 W D = Dry 2007 C 2008 C AN = Above Normal 2009 BN 2010 AN BN = Below Normal 2011 W 2012 D C = Critical EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-30 Table 5-11. Simulated Agricultural and Urban Supply and Demand (Units in Acre-Feet Per Year, AFY) Water Year Type Average Agricultural Demand Average Agricultural Pumping Average Agricultural Sw Deliveries Average Agricultural Effective Precipitation Average Urban Demand Average Urban Pumping Average Urban Sw Deliveries Wet (6 simulated years in the base period) 155,221 35,690 119,603 46,141 29,321 9,007 19,925 Above Normal (3 simulated years in the base period) 162,181 35,028 126,851 41,878 28,946 8,623 19,473 Below Norma (3 simulated years in the base period) 167,090 40,020 127,388 36,044 29,958 8,702 21,288 Dry (5 simulated years in the base period) 173,905 40,385 132,664 32,680 29,990 8,367 21,389 Critical (5 simulated years in the base period) 184,415 36,520 147,764 27,339 32,847 10,070 21,773 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-31 Figure 5-7. Average Simulated Change in Storage by Water Year Type Historical Water Budget The historical water budget quantified during the model Base Period extends from the most recently available information (water year 2018) to 1997, or 22 years. This period is sufficient to calibrate and reduce uncertainty with the ECCSim model, and therefore reduce the uncertainty of the future aquifer response to planned or anticipated changes in land use or hydrology (e.g., climate change or sea level rise). Historical conditions of hydrology, water demand, and surface water supply availability and reliability are the factors that have enabled the ECC Subbasin to operate well within the sustainable yield. In fact, the Subbasin has had stable groundwater levels with no apparent undesirable results as discussed in Section 3, Basin Setting. The historical water budget can be summarized based on water year type, as quantified in the above section and further detailed below. Table 5-12 quantifies the average groundwater budget components based on water year type. These values are also plotted in Figure 5-8. The historical groundwater budget by water year type indicates that tile drains increase the amount of flow leaving the Subbasin during wetter years. The data also show that deep percolation (groundwater recharge) typically increases during wetter years. Surface water leakage (downward migration of surface water) and recoverable losses from diversions increase during drier years as the hydraulic gradient between the water table and surface water bodies increases. The contribution from small watersheds decreases during drier years. Groundwater pumping remains relatively constant regardless of water year type. Subsurface lateral flow also remains generally constant between water year types but shows a slight increase in the amount of water leaving the Subbasin during wetter years. The change in storage does not seem to be directly correlated with water year type, as the basin is full, with stable groundwater levels, and thus operating sustainably. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-32 Table 5-12. Average Simulated Groundwater Budget Components by Water Year Type (Units in Acre-Feet Per Year, AFY) Water Year Type Tile Drains Deep Percolation Surface Water Leakage Small Watershed Contributions Diversion Recoverable Loss Groundwater Pumping Subsurface Lateral Flow Change In Storage Wet (6 simulated years) -87,270 129,214 14,358 1,101 15,855 -44,698 -10,343 26,394 Above Normal (3 simulated years) -75,537 80,228 14,769 12,067 16,628 -43,651 -9,867 -16,279 Below Normal (3 simulated years) -65,831 75,248 21,920 2,558 16,895 -48,722 -6,963 -6,337 Dry (5 simulated years) -64,916 69,809 18,202 7,198 17,506 -48,751 -7,337 -14,618 Critical (5 simulated years) -74,806 78,152 20,758 1,387 19,266 -46,590 -7,556 -3,196 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-33 -100,000 -50,000 0 50,000 100,000 150,000 Tile Drains Deep Percolation Surface Water Leakage Small Watershed Contributions Diversion Recoverable Loss Groundwater Pumping Subsurface Lateral Flow Change in StorageAverage Flow (AFY)Simulated Groundwater Budget Component Wet (6 simulated years)Above Normal (3 simulated years) Below Normal (3 simulated years)Dry (5 simulated years) Average Groundwater Budget Components During the Base Period (1997-2018) by Water Type East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-8 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-34 Summary of Water Year 2015 Water Budget Results For the representative recent water year 2015, the following simulated water budget results are presented. The groundwater budget components for the entire ECC Subbasin are presented in Table 5-13; the root zone budget components are presented in Table 5-14; and the land and water use budget components are presented in Table 5-15. Table 5-13. Groundwater Budget Components for Water Year 2015 (AFY) Water Year Change In Storage Inflow Components Outflow Components Surface Water Features Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Drains Pumping Net Subsurface Flow 2015 13,411 24,787 93,960 572 0 16,452 -66,415 -47,640 -8,290 Table 5-14. Root Zone Budget for Water Year 2015 Land Use Type Land Use Area (Acres) Precipitation (Afy) Applied Water (Afy) Evapotranspiration (Afy) Percolation (Afy) Agricultural 41,329 42,671 166,759 163,801 46,733 Urban 22,585 24,714 25,660 18,676 32,463 Native and Riparian Vegetation 45,236 46,561 0 35,228 11,194 Table 5-15. Land and Water Use Budget Components for Water Year 2015 Agricultural Supply Requirement Agricultural Pumping Agricultural Deliveries Agricultural Shortage Urban Supply Requirement Urban Pumping Urban Deliveries Urban Shortage 166,604 39,747 127,011 -155 25,924 7,893 17,768 264 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-35 Projected 50-Year Water Budget Six different future scenarios were developed to estimate the projected 50-year water budget as follows: o The first future scenario relies on county-provided land use changes to accommodate anticipated urban growth for the year 2036. This future condition is maintained for all the projected 50-year scenarios, refer to Figure 5-9. o The second future scenario uses both the anticipated land use change as well as adjustments for climate change. Following DWR’s guidance document (DWR, 2018), climate adjustments were made to simulated evapotranspiration, precipitation, and surface water levels and delivery model input files using the 2070 central tendency climate change model, refer to Figure 5-10. o The third future scenario uses the anticipated land use change and sea level rise based on repeated hydrology (no climate change) and sea level rise adjustments based on DWR’s guidance documentation. Sea level rise is only applied to model elements in the northern surface water body areas that are below sea level, refer to Figure 5-11. o The fourth future scenario combines all three changes; land use change to accommodate urban growth, climate change (using the 2070 central tendency), and sea level rise, refer to Figure 5-12. o The fifth and sixth future scenarios incorporate the anticipated land use change as well as two extreme climate change models, using climate adjustments for evapotranspiration, precipitation, and surface water levels and delivery model input files. The two scenarios were developed to test the effects of 1) the 2070 wetter with moderate warming climate scenario, and 2) the 2070 drier with extreme warming climate scenario, refer to Figure 5-13, and Figure 5-14, respectively. Projected water demand, surface water supply, and metered urban pumping were based on previously developed amounts presented in Section 4, Table 4-5. ECCSim was used to estimate agricultural and urban demands based on population growth and land use changes and estimated groundwater pumping that would be necessary to meet demands that anticipated surface water deliveries were unable to supply. Hydrology was repeated (or adjusted for climate change) using existing base period model inputs from the historic period of 1954 to 2003. Water year types and patterns of preceding water year types were developed to repeat base period hydrology for the 50-year time period and applying those hydrology values to the future period of 2019-2068 (Table 5-16). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-36 Table 5-16. Future Scenario Water Year Types for Repeated and Adjusted Hydrology Future Scenario Water Year Assigned Historic Simulated Water Year DWR Reference Year for Adjusted Hydrology Projected Water Year Type 16 2019 2011 1954 W 2020 2012 1955 D 2021 2017 1956 W 2022 2018 1957 BN 2023 2017 1958 W 2024 2012 1959 D 2025 2013 1960 C 2026 2014 1961 C 2027 2009 1962 BN 2028 2010 1963 AN 2029 2012 1964 D 2030 2017 1965 W 2031 2018 1966 BN 2032 2011 1967 W 2033 2012 1968 D 2034 2017 1969 W 2035 2010 1970 AN 2036 2009 1971 BN 2037 2012 1972 D 2038 2010 1973 AN 2039 2011 1974 W 2040 2011 1975 W 2041 2013 1976 C 2042 2014 1977 C 2043 2017 1978 W 2044 2010 1979 AN 2045 2011 1980 W 2046 2012 1981 D 2047 2011 1982 W 16 W indicates “wet”, AN indicates “above normal”, BN indicates “below normal”, D indicates “dry”, and C indicates “critical.” EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-37 Future Scenario Water Year Assigned Historic Simulated Water Year DWR Reference Year for Adjusted Hydrology Projected Water Year Type 16 2048 2017 1983 W 2049 2010 1984 AN 2050 2001 1985 D 2051 2011 1986 W 2052 2007 1987 C 2053 2008 1988 C 2054 2007 1989 C 2055 2008 1990 C 2056 2007 1991 C 2057 2008 1992 C 2058 2005 1993 W 2059 1994 1994 C 2060 1995 1995 W 2061 1996 1996 W 2062 1997 1997 W 2063 1998 1998 W 2064 1999 1999 AN 2065 2000 2000 AN 2066 2001 2001 D 2067 2002 2002 D 2068 2003 2003 BN EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-38 -300,000 -200,000 -100,000 0 100,000 200,000 300,000 199719992001200320052007200920112013201520172019202120232025202720292031203320352037203920412043204520472049205120532055205720592061206320652067Acre-feet (AFY)Water Year Net Flow to Storage Surface Water Features Drains Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Pumping Net Subsurface Flow Cumulative Change in storage Groundwater Budget for East Contra Costa Subbasin Future Land Use Scenario (1997-2068) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-9 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-39 -400,000 -300,000 -200,000 -100,000 0 100,000 200,000 300,000 400,000 199719992001200320052007200920112013201520172019202120232025202720292031203320352037203920412043204520472049205120532055205720592061206320652067Acre-feet (AFY)Water Year Net Flow to Storage Surface Water Features Drains Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Pumping Net Subsurface Flow Cumulative Change in Storage Groundwater Budget for East Contra Costa Subbasin Future Land Use and Climate Change Scenario (1997-2068) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-10 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-40 -300,000 -200,000 -100,000 0 100,000 200,000 300,000 199719992001200320052007200920112013201520172019202120232025202720292031203320352037203920412043204520472049205120532055205720592061206320652067Acre-feet (AFY)Water Year Net Flow to Storage Surface Water Features Drains Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Pumping Net Subsurface Flow Cumulative Change in Storage Groundwater Budget for East Contra Costa Subbasin Future Land Use and Sea Level Rise Scenario (1997-2068) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-11 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-41 -400,000 -300,000 -200,000 -100,000 0 100,000 200,000 300,000 400,000 199719992001200320052007200920112013201520172019202120232025202720292031203320352037203920412043204520472049205120532055205720592061206320652067Acre-feet (AFY)Water Year Net Flow to Storage Surface Water Features Drains Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Pumping Net Subsurface Flow Cumulative Change in Storage Groundwater Budget for East Contra Costa Subbasin Future Land Use, Climate Change, and Sea Level Rise Scenario (1997-2068) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-12 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-42 -600,000 -400,000 -200,000 0 200,000 400,000 600,000 199719992001200320052007200920112013201520172019202120232025202720292031203320352037203920412043204520472049205120532055205720592061206320652067Acre-feet (AFY)Water Year Net Flow to Storage Surface Water Features Drains Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Pumping Net Subsurface Flow Cumulative Change in Storage Groundwater Budget for East Contra Costa Subbasin Future Land Use and Climate Change (Wet) Scenario (1997-2068) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-13 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-43 -300,000 -200,000 -100,000 0 100,000 200,000 300,000 199719992001200320052007200920112013201520172019202120232025202720292031203320352037203920412043204520472049205120532055205720592061206320652067Acre-feet (AFY)Water Year Net Flow to Storage Surface Water Features Drains Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Pumping Net Subsurface Flow Cumulative Change in Storage Groundwater Budget for East Contra Costa Subbasin Future Land Use and Climate Change (Dry) Scenario (1997-2068) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-14 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-44 Water Budget Summaries for Future Scenarios The average simulated land and water use budget components are presented in Table 5-17 for the four 50-year future scenarios and the model Base Period. The simulated root zone water budget components are presented in Table 5-18, and the simulated average groundwater budget components are presented in Table 5-19. These tables indicate that land use changes have the most impact on water budget components relative to the Base Period. The future land use change (urban growth), climate change, and sea level rise result in changes in the water budget as follows: • Groundwater pumping is lower on average during the future scenarios due to less agricultural demand as urban growth replaces agricultural land. • There are less surface water contributions to groundwater, but more water leaving the groundwater systems via drains in the future scenarios compared to the baseline scenario. • There is slightly more precipitation during the climate change scenarios, which reduces the amount of applied water for agricultural and outdoor landscaping urban demands. • Sea level rise has very little impact to the groundwater budget, causing a slight decrease in the amount of groundwater exiting the system through drains; increasing the contribution of surface water to groundwater; no major changes to groundwater storage or subsurface lateral flow result from this scenario of sea level rise. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-45 Table 5-17. Simulated Average Future Land and Water Use Budget Components (Units in Acre-Feet per Year, AFY) Land And Water Use Budget Flow Component Base Period (Wy 1997-2018) Future Land Use Scenario (Wy 2019-2068) Future Land Use and Climate Change Scenario (Wy 2019- 2068) Future Land Use and Sea Level Rise Scenario (Wy 2019-2068) Future Land Use, Climate Change, And Sea Level Rise (Wy 2019-2068) Future Land Use and Wet Climate Change Scenario (Wy 2019-2068) Future Land Use and Dry Climate Change Scenario (Wy 2019-2068) Ag. Supply Requirement 162,135 133,678 152,255 133,678 151,626 146,011 161,986 Ag. Pumping 35,742 14,627 12,832 14,627 12,829 11,488 13,120 Ag. Deliveries 126,223 117,735 110,862 117,735 110,236 108,385 120,305 Ag. Demand Shortage 170 1,315 28,561 1,315 28,561 26,138 28,561 Urban Supply Requirement 28,268 35,543 35,543 35,543 35,543 35,543 35,543 Urban Pumping 8,449 14,339 21,124 14,339 21,124 21,111 21,124 Urban Deliveries 19,352 22,759 15,843 22,759 15,843 15,883 15,843 Urban Water Demand Shortage 468 -1,554 -1,424 -1,554 -1,424 -1,450 -1,424 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-46 Table 5-18. Simulated Average Root Zone Budget Components (Area in acres, Flows in AFY) Root Zone Budget Flow Component Base Period (Wy 1997-2018) Water Year 2015 Future Land Use Scenario (Wy 2019-2068) Future Land Use and Climate Change Scenario (Wy 2019-2068) Future Land Use and Sea Level Rise Scenario (Wy 2019-2068) Future Land Use, Climate Change, And Sea Level Rise (Wy 2019-2068) Future Land Use and Wet Climate Change Scenario (Wy 2019-2068) Future Land Use and Dry Climate Change Scenario (Wy 2019-2068) Agricultural Land Use Area (acres) 48,057 41,329 36,171 36,171 36,171 36,171 36,171 36,171 Ag. Precipitation (+) 55,998 42,671 43,681 46,131 43,681 46,131 57,301 40,900 Ag. Applied Water (+) 161,965 166,759 132,363 123,694 132,363 123,065 119,872 129,561 Ag. ET (-) 170,998 163,801 137,764 134,522 137,764 133,841 131,369 137,784 Ag. Percolation (-) 47,182 46,733 38,275 35,302 38,275 35,354 45,803 32,678 Urban Land Use Area (acres) 20,045 22,585 36,038 36,038 36,038 36,038 36,038 36,038 Urban Precipitation (+) 22,929 24,714 43,088 45,517 43,088 45,517 58,384 40,416 Urban Applied Water (Landscaping) (+) 27,800 25,660 37,098 36,967 37,098 36,967 36,993 36,558 Urban ET (-) 19,516 18,676 31,714 31,638 31,714 31,638 31,823 30,143 Urban Percolation (-) 31,539 32,463 48,654 51,029 48,654 51,029 63,737 47,014 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-47 Root Zone Budget Flow Component Base Period (Wy 1997-2018) Water Year 2015 Future Land Use Scenario (Wy 2019-2068) Future Land Use and Climate Change Scenario (Wy 2019-2068) Future Land Use and Sea Level Rise Scenario (Wy 2019-2068) Future Land Use, Climate Change, And Sea Level Rise (Wy 2019-2068) Future Land Use and Wet Climate Change Scenario (Wy 2019-2068) Future Land Use and Dry Climate Change Scenario (Wy 2019-2068) Native & Riparian Veg. Land Use Area (acres) 41,048 45,236 36,942 36,942 36,942 36,942 36,942 36,942 Native & Riparian Veg. Precipitation (+) 46,290 46,561 44,317 46,669 44,317 46,669 58,689 41,146 Native & Riparian Veg. ET (-) 37,142 35,228 35,783 36,255 35,783 36,255 39,236 32,700 Sum of Native & Riparian Veg. Percolation (-) 9,042 11,194 8,535 10,414 8,535 10,414 19,454 8,447 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-48 Table 5-19. Simulated Average Groundwater Budget Component Flows (Units in Acre-Feet per Year, AFY) Groundwater Budget Flow Component Base Period (Wy 1997-2018) Water Year 2015 Future Land Use Scenario (Wy 2019-2068) Future Land Use and Climate Change Scenario (Wy 2019-2068) Future Land Use and Sea Level Rise Scenario (Wy 2019-2068) Future Land Use, Climate Change, and Sea Level Rise (Wy 2019-2068) Future Land Use and Wet Climate Change Scenario (Wy 2019-2068) Future Land Use and Dry Climate Change Scenario (Wy 2019-2068) Drains -74,833 -87,732 -87,732 -84,026 -86,521 -81,068 -103,007 -75,807 Surface Water Features 17,773 12,517 12,517 13,859 13,300 14,644 6,880 16,148 Deep Percolation 90,069 95,701 95,701 97,002 95,702 97,054 129,520 88,301 Small Watershed Baseflow 976 880 880 647 880 647 787 452 Small Watershed Percolation 2,260 2,051 2,051 1,645 2,051 1,645 2,124 1,132 Diversion Recoverable Loss 17,253 15,965 15,965 14,398 15,965 14,327 14,121 14,774 Pumping -46,455 -28,966 -28,966 -33,956 -28,966 -33,952 -32,599 -36,106 Net Subsurface Flow -8,500 -12,975 -12,975 -11,423 -12,985 -11,432 -14,847 -10,013 Net Storage Change 66 2,799 2,799 2,451 2,807 2,457 4,360 1,721 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-49 Model Calibration and Uncertainty The ECCSim model was calibrated to match measured groundwater levels at various monitoring locations and depths throughout the model domain and Subbasin area. Due to the engineered nature of surface water features in this area and therefore their simulation, calibration using surface water elevations and flows were not performed. Matching simulated groundwater levels to actual observed groundwater levels in specific wells with known depths is a useful measure of the appropriateness of the model to be used as a tool for determining sustainability under various stresses. Thirty-three wells were used to calibrate the model. Most wells were calibrated to match measured water levels within 10 feet. Many wells were calibrated to match with even less uncertainty. Some wells have better matches than others, and attempts were made to adjust aquifer parameters to accommodate better matches on a regional scale. Local changes to aquifer parameters just to improve those results were avoided; rather, the best assessment of hydrogeologic conditions was made leaving the opportunity for future data acquisition to update the model and possibly improve calibration in those areas. The full set of simulated and observed groundwater levels for all calibration wells is provided in the model report found in Appendix 5a. A subset of these calibration plots are provided here (Figure 5-15) to illustrate favorable matches throughout the model domain both vertically and laterally. Another plot that shows the scatter plot of measured versus simulated groundwater levels using all measurements over the entire simulation period (Figure 5-16). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-50 Figure 5-15 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-51 Verification of Shallow Zone Results • Examination of DuPont site data as requested by DWD (TBD) Sensitivity Analysis (TBD) o Development and explanation of model sensitivity runs for the integrated hydrologic model in order to help determine sustainable yield. o Testing the hydraulic connectivity between layers during a high pumping scenario (the sustainable yield model run) by decreasing the vertical hydraulic conductivity. o Results of sensitivity runs. Sustainable Yield Scenario In order to estimate the sustainable yield of the ECC Subbasin, the future land use change scenario was utilized with the ECCSim tool. Surface water diversions were reduced and substituted with increased groundwater extraction. This trial-and-error process was repeated until the following negative impacts occurred in relation to the historical baseline: • The average change in storage indicated aquifer depletion; • The surface water contributions to groundwater indicated stream depletion; • The gradient for subsurface lateral flow changed such that flow out of the Subbasin reversed with flow into the ECC Subbasin from neighboring subbasins. Figure 5-16 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-52 With regard to surface water interactions, it is possible to identify the range of stream depletion that has been occurring in the past and use those quantities to identify a significant change in the sustainability scenario. This does not necessarily mean that a change from the historic baseline represents undesirable results, only that greater pumping is offset by a contribution from the stream depletion source that is outside the historic range. The range of historical surface water contribution to the ECC Subbasin in the Base Period was estimated at between: 9,481 to 30,852 AFY. Here, a positive value indicates a contribution to groundwater storage from stream surface water sources. Similar to the stream depletion factor, the range of historic simulated annual flow to other basins, or subsurface lateral flow, is between -4,664 to -15,817 AFY. Here, a negative value indicates flow out of the ECC Subbasin. To estimate sustainable yield, the average surface water contribution water budget component and subsurface lateral flow attempted to be within the range of approximate simulated historic values. The quantification of cumulative change in storage combined with the criteria for surface water contribution and subsurface lateral flow, allow for a better understanding of what levels of groundwater pumping amounts could result in adverse effects such as storage depletion. Average annual groundwater pumping in the model Base Period accounts was approximately 46,500 AFY. As a perspective on historic and current basin conditions, this annual average pumping rate has occurred with no apparent undesirable results as defined under SGMA. In fact, the Subbasin relies heavily on drains to remove excess groundwater which is a function of the Delta setting in which land is largely near sea level, groundwater is encountered at shallow depths, sometimes only a few feet, and streams and rivers are hydraulically connected to the aquifer system. Reducing the surface water deliveries and increasing groundwater pumping allows the basin to be stressed in a manner that alters the historic balance in the water budget components. Table 5-20 shows average groundwater budget components for a subset of the sustainable yield model runs used to develop an estimate of sustainable yield, using groundwater budget terms within the range of values seen during the Base Period. The cumulative change in storage is plotted for selected sustainable yield scenario runs to test the Increased pumping to levels to aquifer storage depletion or replenishment (Figure 5-17). The sustainable yield value of 72,000 AFY satisfies the criteria for not negatively impacting surface water features or altering flow patterns between neighboring subbasins, but still results in aquifer replenishment over time. Sustained pumping of 72,000 AFY will result in slightly less reliance on drains, while maintaining a cumulative change in storage above zero without depleting surface water or negatively impacting neighboring subbasins. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-53 ECC Subbasin Sustainable Yield In summary, the sustainable yield for the ECC Subbasin is approximately 72,000 AFY. This amount of groundwater extraction does not result in storage depletion, does not result in surface water depletion beyond levels seen in the model Base Period, reduces the drain outflow, and reduces reliance on surface water deliveries. At higher levels of pumping, the modeling indicates the potential to increase streamflow depletion and inter-basin flow beyond historical baselines. Like the Base Period scenario, a chronic decline in groundwater storage was not a factor in the sustainable yield threshold. The margin between the average pumping rate in the subbasin during the base period (46,455 AFY) and the quantified sustainable yield of 72,000 AFY provides an ability to meet short-term surface water supply shortages in dry to critically dry years through increased groundwater pumping. This margin is a hallmark of effective conjunctive use of surface water and groundwater resources which is based on the fact that surface water and groundwater resources vary in availability, quality, and costs. In the ECC Subbasin, the margin between sustainable yield and average pumping provides a storage buffer in critically dry years. Some GSAs have implemented groundwater exchanges (East Contra Costa Irrigation District) and supplemental groundwater capacity (Diablo Water District). These and similar programs can mitigate impacts to overall water supply in not only dry and critically dry periods, but also as a result of unforeseen climate change consequences. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-54 Table 5-20. Average Simulated Groundwater Budget Components Used to Develop the Sustainable Yield of the ECC Subbasin Groundwater Budget Flow Component Base Period (Wy 1997-2018) Water Year 2015 Minimum Annual Base Period Value Maximum Base Period Value Future Land Use Scenario (Wy 2019-2068) Sustainable Yield Run: Reduce Sw Deliveries By 75% Sustainable Yield Run: Reduce Sw Deliveries By 50% Sustainable Yield Run: Reduce SW Deliveries By 45% Sustainable Yield Run: Reduce SW Deliveries By 40% Drains -74,833 -66,415 -116,071 -56,081 -87,732 -34,458 -56,883 -59,623 -61,157 Surface Water Features 17,773 24,787 9,481 30,852 12,517 26,851 19,167 18,096 17,081 Deep Percolation 90,069 93,960 50,799 184,027 95,701 95,567 95,982 96,023 96,057 Small Watershed Baseflow 976 572 498 2,320 880 880 880 880 880 Small Watershed Percolation 2,260 0 0 26,702 2,051 2,051 2,051 2,051 2,051 Diversion Recoverable Loss 17,253 16,452 14,255 21,747 15,965 6,879 11,132 11,824 12,490 Pumping -46,455 -47,640 -58,251 -32,504 -28,966 -109,353 -71,992 -65,915 -60,064 Net Subsurface Flow -8,500 -8,290 -15,817 -4,664 -12,975 8,313 -3,658 -5,189 -6,594 Net Storage Change 66 13,411 -43,556 65,310 2,799 63 1,940 2,130 2,303 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-55 -150,000 -100,000 -50,000 0 50,000 100,000 150,000 200,000 250,000 Acre-feet (AFY)Water Year Future Land Use (Urban Growth) 109,000 AFY Pumping (reduction of 75% of surface water deliveries) Sustainable Yield (72,000 AFY Pumping, a reduction of 50% of surface water deliveries) 60,000 AFY Pumping (reduction of 40% of surface water deliveries) Simulated Cumulative Change in Groundwater Storage for Sustainable Yield Development East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-17 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-56 GSA Area Water Budget Results The seven GSAs that comprise the ECC Subbasin have their own water budgets as simulated using the ECCSim tool. The average groundwater budget terms are quantified for each GSA for the model Base Period (water years 1997-2018) in Table 5-21. The average simulated groundwater budget components are illustrated graphically in Figure 5-18. The projected water budgets for GSA areas were determined for the four 50-year water budget scenarios: o future land use scenario (repeated hydrology); o future land use plus climate change scenario (using 2070 central tendency climate change adjustments, the 2070 wet climate change adjustments, and the 2070 dry climate change adjustments); o future land use plus sea level rise scenario; and o future land use plus climate change and sea level rise scenario. Simulated groundwater budget components are presented below in Table 5-22. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-57 Table 5-21. Simulated Groundwater Budget Components for GSAs in the ECC Subbasin for Base Period, WY 1997-2018 (Units are in Acre-Feet per Year, AFY) GSAS Net Storage Change Drains Surface Water Features Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Pumping Net Subsurface Flow Outside Basin Net Subsurface Inter-Basin Flow City of Antioch GSA -785 0 -1,036 14,663 129 406 1,472 -1,152 -1,647 -13,621 Diablo Water District GSA 86 -559 2,572 8,151 0 82 423 -17,216 -208 6,836 County of Contra Costa GSA -210 -73,302 16,665 43,071 0 0 10,699 -7,408 -8,021 16,533 City of Brentwood GSA 2,276 0 2,478 12,036 330 741 915 -11,226 0 -2,999 ECC Irrigation District GSA -524 -1,083 900 6,363 348 773 2,536 -5,370 0 -4,991 Discovery Bay CSD GSA -9 -3,735 0 3,540 0 0 111 -3,747 0 3,822 Byron Bethany Irrigation District - ECC GSA -806 -4,582 0 6,994 168 258 1,096 -334 1,196 -5,580 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-58 -100,000 -80,000 -60,000 -40,000 -20,000 0 20,000 40,000 60,000 80,000 100,000 City of Antioch GSA Diablo Water District GSA County of Contra Costa GSA City of Brentwood GSA ECC Irrigation District GSA Discovery Bay CSD GSA Byron Bethany Irrigation District - ECC GSAAverage Annual Water Budget Flow (AFY)Net Flow to Storage Surface Water Features Drains Deep Percolation Small Watershed Baseflow Small Watershed Percolation Diversion Recoverable Loss Pumping Net Subsurface Flow Outside Basin Net Subsurface Inter-Basin Flow Average Water Budget Components During the Historical Calibration Period (1997-2018) East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim) Report Figure 5-18 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-59 Table 5-22. Simulated Future Scenario Groundwater Budgets for Individual GSAs GSA Groundwater Budget Component Flows Summary City of Antioch GSA Base Period (WY 1997-2018) Future Land Use Scenario (WY 2019-2068) Future Land Use and Climate Change Scenario17 (WY 2019-2068) Future Land Use and Sea Level Rise Scenario (WY 2019-2068) Future Land Use, Climate Change 18, and Sea Level Rise (WY 2019-2068) Net Storage Change -785 142 171 142 171 Drains 0 0 0 0 0 Surface Water Features -1,036 -1,920 -1,833 -1,923 -1,836 Deep Percolation 14,663 14,914 15,630 14,914 15,630 Small Watershed Baseflow 129 99 76 99 76 Small Watershed Percolation 406 327 279 327 279 Diversion Recoverable Loss 1,472 1,322 1,313 1,322 1,313 Pumping -1,152 -255 -278 -255 -278 Net Subsurface Flow Outside Basin -1,647 -3,261 -2,864 -3,259 -2,863 Net Subsurface Inter-Basin Flow -13,621 -11,084 -12,152 -11,083 -12,150 17 2070 Central Tendency Climate Change Scenario 18 2070 Central Tendency Climate Change Scenario EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-60 GSA Groundwater Budget Component Flows Summary Diablo Water District GSA Base Period (WY 1997-2018) Future Land Use Scenario (WY 2019-2068) Future Land Use and Climate Change Scenario (WY 2019-2068) Future Land Use and Sea Level Rise Scenario (WY 2019-2068) Future Land Use, Climate Change, and Sea Level Rise (WY 2019-2068) Net Storage Change 86 176 151 176 151 Drains -559 -2,495 -2,255 -2,492 -2,262 Surface Water Features 2,572 -321 389 -338 372 Deep Percolation 8,151 10,224 10,881 10,224 10,881 Small Watershed Baseflow 0 0 0 0 0 Small Watershed Percolation 82 42 70 42 70 Diversion Recoverable Loss 423 404 398 404 398 Pumping -17,216 -6,141 -6,465 -6,141 -6,465 Net Subsurface Flow Outside Basin -208 -677 -613 -675 -612 Net Subsurface Inter-Basin Flow 6,836 -861 -2,255 -847 -2,233 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-61 GSA Groundwater Budget Component Flows Summary County of Contra Costa GSA Base Period (WY 1997-2018) Future Land Use Scenario (WY 2019-2068) Future Land Use and Climate Change Scenario (WY 2019-2068) Future Land Use and Sea Level Rise Scenario (WY 2019-2068) Future Land Use, Climate Change, and Sea Level Rise (WY 2019-2068) Net Storage Change -210 90 115 99 124 Drains -73,302 -80,933 -76,509 -79,771 -73,513 Surface Water Features 16,665 14,906 15,740 15,721 16,556 Deep Percolation 43,071 42,783 40,623 42,784 40,624 Small Watershed Baseflow 0 0 0 0 0 Small Watershed Percolation 0 0 0 0 0 Diversion Recoverable Loss 10,699 10,399 9,373 10,399 9,373 Pumping -7,408 -10,137 -7,693 -10,137 -7,693 Net Subsurface Flow Outside Basin -8,021 -11,880 -11,567 -11,892 -11,619 Net Subsurface Inter-Basin Flow 16,533 29,466 25,726 29,449 25,691 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-62 GSA Groundwater Budget Component Flows Summary City of Brentwood GSA Base Period (WY 1997-2018) Future Land Use Scenario (WY 2019-2068) Future Land Use and Climate Change Scenario (WY 2019-2068) Future Land Use and Sea Level Rise Scenario (WY 2019-2068) Future Land Use, Climate Change, and Sea Level Rise (WY 2019-2068) Net Storage Change 2,276 2,078 1,728 2,079 1,729 Drains 0 0 0 0 0 Surface Water Features 2,478 1,982 2,035 1,982 2,035 Deep Percolation 12,036 14,213 14,738 14,213 14,738 Small Watershed Baseflow 330 278 199 278 199 Small Watershed Percolation 741 604 475 604 475 Diversion Recoverable Loss 915 902 117 902 117 Pumping -11,226 -4,605 -11,592 -4,605 -11,592 Net Subsurface Flow Outside Basin 0 0 0 0 0 Net Subsurface Inter-Basin Flow -2,999 -11,295 -4,245 -11,294 -4,244 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-63 GSA Groundwater Budget Component Flows Summary ECCID GSA Base Period (WY 1997-2018) Future Land Use Scenario (WY 2019-2068) Future Land Use and Climate Change Scenario (WY 2019-2068) Future Land Use and Sea Level Rise Scenario (WY 2019-2068) Future Land Use, Climate Change, and Sea Level Rise (WY 2019-2068) Net Storage Change -524 116 48 116 48 Drains -1,083 -1,512 -1,696 -1,513 -1,698 Surface Water Features 900 666 740 666 740 Deep Percolation 6,363 5,337 5,988 5,337 5,988 Small Watershed Baseflow 348 332 241 332 241 Small Watershed Percolation 773 924 607 924 607 Diversion Recoverable Loss 2,536 2,106 2,284 2,106 2,284 Pumping -5,370 -794 -869 -794 -869 Net Subsurface Flow Outside Basin 0 0 0 0 0 Net Subsurface Inter-Basin Flow -4,991 -6,942 -7,246 -6,941 -7,245 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-64 GSA Groundwater Budget Component Flows Summary Discovery Bay CSD GSA Base Period (WY 1997-2018) Future Land Use Scenario (WY 2019-2068) Future Land Use and Climate Change Scenario (WY 2019-2068) Future Land Use and Sea Level Rise Scenario (WY 2019-2068) Future Land Use, Climate Change, and Sea Level Rise (WY 2019-2068) Net Storage Change -9 14 17 14 17 Drains -3,735 -4,969 -5,268 -4,969 -5,267 Surface Water Features 0 0 0 0 0 Deep Percolation 3,540 5,743 6,149 5,743 6,149 Small Watershed Baseflow 0 0 0 0 0 Small Watershed Percolation 0 0 0 0 0 Diversion Recoverable Loss 111 1 1 1 1 Pumping -3,747 -6,626 -6,626 -6,626 -6,626 Net Subsurface Flow Outside Basin 0 0 0 0 0 Net Subsurface Inter-Basin Flow 3,822 5,866 5,761 5,866 5,760 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 – WATER BUDGET LSCE 5-65 GSA Groundwater Budget Component Flows Summary Byron Bethany Irrigation District - ECC GSA Base Period (WY 1997-2018) Future Land Use Scenario (WY 2019-2068) Future Land Use and Climate Change Scenario (WY 2019-2068) Future Land Use and Sea Level Rise Scenario (WY 2019-2068) Future Land Use, Climate Change, and Sea Level Rise (WY 2019-2068) Net Storage Change -806 194 232 194 230 Drains -4,582 -4,220 -4,764 -4,220 -4,747 Surface Water Features 0 0 0 0 0 Deep Percolation 6,994 7,399 8,223 7,399 8,273 Small Watershed Baseflow 168 171 131 171 131 Small Watershed Percolation 258 154 214 154 214 Diversion Recoverable Loss 1,096 831 912 831 841 Pumping -334 -407 -433 -407 -429 Net Subsurface Flow Outside Basin 1,196 1,475 1,598 1,475 1,599 Net Subsurface Inter-Basin Flow -5,580 -5,149 -5,589 -5,149 -5,579 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 5 - EAST CONTRA COSTA SUBBASIN WATER BUDGET LSCE 5-66 Model Documentation Appendix 5a contains model documentation and complete scenario results. References California Department of Water Resources (DWR). December 2016. Guidance Document for the Sustainable Management of Groundwater: Modeling. California Department of Water Resources (DWR). December 2016. Guidance Document for the Sustainable Management of Groundwater: Water Budget. California Department of Water Resources (DWR). July 2018. Sustainable Groundwater Management Program: Guidance for Climate Change Data Use During Groundwater Sustainability Plan Development. California Department of Water Resources (DWR). July 2018. Sustainable Groundwater Management Program: Resource Guide DWR-Provided Climate Change Data and Guidance for Use During Groundwater Sustainability Plan Development. California Department of Water Resources (DWR). January 2021. Sustainable Groundwater Management Act Water Year Type Dataset Development Report. California Department of Water Resources (DWR). July 2018. Sustainable Groundwater Management Program: Resource Guide DWR-Provided Climate Change Data and Guidance for Use During Groundwater Sustainability Plan Development. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 – MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-i SECTION 6 CONTENTS 6. Monitoring Network and Data Management System ................................................................6-1 6.1. Monitoring Network Objectives (CCR§354.34, §354.38) .......................................................... 6-1 6.2. Monitoring Networks ................................................................................................................ 6-2 6.2.1. Basin-Wide and Representative Monitoring Networks ..................................................... 6-2 6.2.2. Groundwater Level Monitoring Network .......................................................................... 6-3 6.2.2.1. Basin-wide Groundwater Level Monitoring Network……………………………………………………6-4 6.2.2.2. Spatial Density of Groundwater Level Monitoring Network………………………………………..6-11 6.2.2.3. Frequency and Timing of Groundwater Level Monitoring…………………………………………..6-12 6.2.2.4. Groundwater Level Data Gaps……………………………………………………………………………………6-12 6.2.2.5. Plan to Fill Groundwater Level Data Gaps………………………………………………………………….6-12 6.2.3. Groundwater Quality Monitoring Network ..................................................................... 6-14 6.2.3.1. Basin-wide Groundwater Quality Monitoring Network………………………………………………6-15 6.2.3.2. Representative Groundwater Quality Monitoring Network………………………………………6-19 6.2.3.3. Spatial Density, Frequency, and Data Gaps of Groundwater Quality Monitoring Network…………………………………………………………………………………………………………………….6-19 6.2.4. Seawater Intrusion Monitoring Network ......................................................................... 6-19 6.2.5. Land Subsidence Monitoring Network ............................................................................ 6-21 6.2.6. Interconnected Surface Water Monitoring Network....................................................... 6-23 6.3. Protocols for Data Collection and Monitoring (§ 352.2) ......................................................... 6-26 6.4. Data Gaps ................................................................................................................................. 6-26 6.4.1. Well Inventory Data Gap .................................................................................................. 6-27 6.5. Ongoing Monitoring Network Evaluation................................................................................ 6-28 6.6. Groundwater Data Management ............................................................................................ 6-28 6.7. Data Management System (§ 352.6) ....................................................................................... 6-28 6.8. Data Use and Disclosure .......................................................................................................... 6-29 6.9. Data Submittals ....................................................................................................................... 6-29 6.10. Reporting ................................................................................................................................. 6-29 6.11. References ............................................................................................................................... 6-29 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 – MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-ii LIST OF TABLES Table 6-1 Sustainability Indicators and Applicable Representative Monitoring Network……….…….6-2 Table 6-2 GSA Groundwater Level Monitoring Network………………………………………………………………6-3 Table 6-3 Basin-wide and Representative Groundwater Level Monitoring Network…………………...6-4 Table 6-4 Groundwater Level Monitoring Well Density Considerations……………………………………..6-11 Table 6-5 Subbasin Groundwater Level Monitoring Networks Density………………………………………6-12 Table 6-6 Proposed New Monitoring Wells to Fill Data Gaps……………………………………………………..6-14 Table 6-7 GSA Groundwater Quality Monitoring Network…………………………………………………………6-15 Table 6-8 Basin-Wide and Representative Groundwater Quality Monitoring Network………………6-16 Table 6-9 Basin-wide Interconnected Surface Water Monitoring Network………………………………..6-25 LIST OF FIGURES Figure 6-1a Basin-wide Groundwater Level Monitoring Network – Shallow Zone……………………….…6-5 Figure 6-1b Basin-wide Groundwater Level Monitoring Network – Deep Zone………………………………6-6 Figure 6-2 Representative Groundwater Level Monitoring Network…………………………………………..6-10 Figure 6-3 Data Gap – Shallow Zone Groundwater Level Monitoring Network……………………………6-13 Figure 6-4 Basin-wide Groundwater Quality Monitoring Network………………………………………………6-18 Figure 6-5 Representative Groundwater Quality Monitoring Network………………………………….……6-20 Figure 6-6 Land Subsidence Monitoring Network……………………………………………………………………….6-22 Figure 6-7 Interconnected Surface Water Monitoring Network………………………………………………….6-24 LIST OF APPENDICES Appendix 6a Monitoring Protocols EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 – MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-1 6. MONITORING NETWORK AND DATA MANAGEMENT SYSTEM SGMA regulations require that each GSP develop a monitoring network to collect data of sufficient accuracy and quantity to evaluate changing conditions and trends in groundwater and related surface water, as well as to provide representative information about groundwater conditions. The monitoring network and associated data shall be used to demonstrate that the basin is sustainably managed. SGMA also requires that monitoring networks specifically target the six sustainability indicators1 either directly or indirectly through a proxy monitoring parameter. The six sustainability indicators are: chronic lowering of groundwater levels, reduction in groundwater storage, seawater intrusion, degraded water quality, land subsidence, and depletion of interconnected surface water. This section describes the monitoring networks, monitoring protocols, data management system, and data reporting requirements for the ECC Subbasin GSP. The ECC Subbasin monitoring networks shall be assessed every five years. Through these assessments, needed changes and/or data gaps may be identified. The GSAs shall adaptively manage and modify the monitoring networks, projects, management actions, and/or interim milestones to achieve the sustainability objectives for the Subbasin. This process is intended to conform to Monitoring Networks and Identification of Data Gaps, Best Management Practices, (DWR, 2016). 6.1. Monitoring Network Objectives (CCR§354.34, §354.38) In accordance with GSP Regulations, monitoring networks shall be developed to produce a data set of sufficient accuracy, measurement frequency, and spatial distribution to characterize groundwater and related surface water conditions in the plan area and to evaluate conditions through implementation of the GSP all with the purpose of sustainable groundwater management. The monitoring network shall accomplish the following (GSP Reg. § 354.34(b)(1)-(4)): (1) Demonstrate progress towards achieving measurable objectives described in the GSP. (2) Monitor impacts to the beneficial uses and users of groundwater. (3) Monitor changes in groundwater conditions relative to measurable objectives and minimum thresholds. (4) Quantify annual changes in water budget components. The ECC GSP monitoring network is designed to meet the above regulatory requirements through implementation of monitoring described in this section. As discussed in this section, designated monitoring sites throughout the Subbasin, with appropriate monitoring protocols and measurement frequency, will provide a means to quantify current and future hydrogeological conditions of the ECC Subbasin, as well as within individual GSA jurisdictions. 1 Sustainability indicator in SGMA refers to “any of the effects caused by groundwater conditions occurring throughout the basin that, when significant and unreasonable, cause undesirable results…” (DWR, BMP, 2016) EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 – MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-2 6.2. Monitoring Networks Under SGMA, monitoring networks shall be established for each of six sustainability indicators as applicable. The six sustainability indicators are: chronic lowering of groundwater levels, reduction of groundwater storage, seawater intrusion, degraded water quality, land subsidence, and depletion of interconnected surface water. The groundwater level monitoring network will act as a proxy for the groundwater storage sustainability indicator. Existing groundwater, surface water and subsidence monitoring programs conducted by DWR, SWCRB, DDW, USGS and UNAVCO, are described in Section 2.2. In addition to these programs, five ECC GSAs (City of Brentwood, BBID, TODB and DWD, and ECCID) have independent groundwater monitoring programs. These existing programs are integrated into the GSP monitoring program where applicable to the monitoring objectives. Table 6-1, below, summarizes the sustainability indicators and related monitoring in the ECC GSP. Table 6-1. Sustainability Indicators and Applicable Representative Monitoring Network Sustainability Indicator Representative Monitoring Network Proxy Network Chronic Lowering of Groundwater Levels Groundwater Levels NA Reduction of Groundwater Storage See Proxy Groundwater Levels Seawater Intrusion Groundwater Quality NA Degraded Groundwater Quality Groundwater Quality NA Land Subsidence PBO Station Groundwater Levels Surface Water Depletion due to Groundwater Pumping Stream Flow Groundwater Levels NA = Not Applicable 6.2.1. Basin-Wide and Representative Monitoring Networks The GSP monitoring program includes basin-wide and representative networks. The basin-wide network provides a broad source of relevant data by which to evaluate conditions in the Subbasin. The representative network is a subset of the basin-wide network for which minimum thresholds and measurable objectives shall be defined in accordance with CCR§354.36 (a) (see Section 7 of this GSP). For each monitoring network (i.e., basin-wide, and representative monitoring site), the following information is discussed below: the site locations, spatial density, monitoring frequency, monitoring protocols, data gaps, and a plan to fill the data gaps. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 – MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-3 6.2.2. Groundwater Level Monitoring Network Groundwater level monitoring is a fundamental component of data collection for sustainable groundwater management. Groundwater level data from a network of groundwater monitoring wells serve to show groundwater occurrence, flow direction, hydraulic gradients between principal aquifers, and interaction between groundwater and surface water features (CCR§354.34 (C)). Each GSA has dedicated monitoring wells in its area of jurisdiction. GSA monitoring wells have existing historical records dating to the 1950s (e.g., ECCID monitoring network for shallow groundwater). The various GSA networks were initially coordinated through the State CASGEM program in 2013. The basin-wide and representative groundwater level networks are summarized below and enumerated in Table 6-2: • Basin-wide Monitoring Network - The basin-wide monitoring network for groundwater level evaluation provides a broad dataset for basin evaluation. • Representative Monitoring Network - A subset of basin-wide monitoring wells is selected to monitor sustainability indicators in the Subbasin and to demonstrate sustainable management in accordance with defined minimum thresholds and measurable objectives for the chronic lowering of groundwater levels sustainability indicator. Table 6-2. GSA Groundwater Level Monitoring Network GSA Number of Wells Basin-Wide Network Representative Network Existing New Total BBID 5 5 1 City of Antioch 3 3 2 City of Brentwood 6 6 2 Contra Costa County 2 2 1 Diablo Water District 10 2 12 3 Town of Discovery Bay 9 2 11 2 ECCID 16 16 1 Total 46 9 55 12 Note: multiple completion monitoring wells are counted as separate wells for each depth. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 – MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-4 6.2.2.1. Basin-wide Groundwater Level Monitoring Network As indicated in Table 6-2, 55 wells are included in the basin-wide monitoring network. Well selection criteria included the following: 1. Are representative of groundwater level conditions in the Subbasin and provide monitoring in the two principal aquifers in the Subbasin: Shallow Zone and Deep Zone. 2. GSAs are committed to semiannual monitoring and are typically part of an existing monitoring program. 3. A historical data record exists. Well locations for the basin-wide groundwater level monitoring network are shown on Figures 6-1a and 6-1b. Figure 6-1a show wells that monitor the Shallow Zone aquifer and Figure 6-1b shows wells that monitor the Deep Zone. These principal aquifers are described under Basin Setting Section 3.2.5 and reflect the vertical discretization of groundwater occurrence in the ECC Subbasin. Figures 6-1a and 6-1b include new wells to be installed as part of the GSP implementation. These wells are intended to fill data gaps and are discussed in Section 6.2.3. Details of the monitoring network are provided in Table 6-3 including name, owner, coordinates, reference point elevation (RPE), and perforation depths. Of the 55 basin-wide monitoring wells, 31 are perforated in the Shallow Zone and 19 wells are perforated in the Deep Zone. In addition, 14 nested (two or more casings within the same borehole) or multi-completion, monitoring wells located at 6 different sites are in the network (Figure 6-1b). CASGEM wells form a substantial part of monitoring network with 26 wells from this program. With a few exceptions, basin-wide network wells are dedicated groundwater monitoring wells with known construction features and screened only in the designated aquifer zone. Wells that are perforated through both the shallow and deep aquifer zones are not included in the monitoring network nor are wells with unknown construction features. The exceptions to this are three composite wells listed in Table 6-3 and show on Figure 6-1b that are included to improve groundwater level contouring in areas lacking well control. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 – MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-5 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 – MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-6 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 – MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-7 Table 6-3. Basin-wide and Representative Groundwater Level Monitoring Local Well Name Well Owner/GSA Latitude Longitude Reference Point Elevation (ft) Perforation Depths (ft bgs) CASGEM Well Frequency Representative Well Shallow Zone Wells Antioch MW-15ǂ Antioch 38.018901 -121.819755 4.12 5-15 No daily* X Antioch MW-30ǂ Antioch 38.018887 -121.819753 4.12 20-30 No daily* 1 JNJ BBID 37.906128 -121.6419204 26.63 105-120 Yes monthly 3 Byron BBID 37.8684118 -121.6412186 32.28 50-70 Yes monthly 4 Bruns BBID 37.8168913 -121.5991577 35.87 45-65 Yes monthly 5 Binn BBID 37.8506993 -121.6238007 24.42 45 (TD) Yes-Vol- untary monthly X New Well CCC/CCWD No daily* X New Well CCC/CCWD No daily* BG-1 CofB 37.9638969 -121.6933943 71.22 40-55 No monthly BG-2 CofB 37.9589412 -121.6917498 62.09 22.5-37.5 No monthly X BG-3 CofB 37.9546062 -121.6824842 55.6 20-35 No monthly DWD MW-15ǂ DWD 38.015495 -121.639343 7.31 5-15 No daily* DWD MW-30ǂ DWD 38.015531 -121.639343 7.26 20-30 No daily* X Stonecreek MW-160 DWD 37.978122 -121.683968 30.76 100-110, 140-150 Yes monthly? 4-1 ECCID 37.91888889 -121.6408333 13 0-10 No semi-annual 4-18 ECCID 37.94027778 -121.6408333 24.6 NA No semi-annual 5-14 ECCID 37.96527778 -121.6455556 18.7 NA No semi-annual 5-22 ECCID 37.97305556 -121.6594444 17.2 0-10 Yes semi-annual 5-31 ECCID 37.94944444 -121.6641667 45.5 0-10 No semi-annual 5-33 ECCID 37.98833333 -121.6775 13.3 0.01 - 20 Yes monthly 5-36 ECCID 37.97277778 -121.6775 27.4 0-10 Yes monthly 5-39 ECCID 37.98444444 -121.6683333 12.5 0.01 - 20 Yes monthly 5-51 ECCID 37.95777778 -121.6777778 54.1 0-11 No semi-annual Well #1 (4-54) ECCID 37.91805556 -121.6983333 85.9 85-165 No monthly Well # 2 (5-30) ECCID 37.91777778 -121.6594444 40.3 0-30 No monthly Well #6 (4-60) ECCID 37.92555556 -121.6625 49.5 30-50 No monthly Well #11 (4-61-A) ECCID 37.91777778 -121.67 55.5 50-100 Yes monthly X TODB MW-15 TODB 5-15 No daily* TODB MW-30 TODB 20-30 No daily* X 1BMW-140 TODB 37.9102996 -121.5993985 4.31 100-130 Yes semi-annual 4AMW-152 TODB 37.9009991 -121.6187989 11.67 122-142 Yes EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 – MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-8 Local Well Name Well Owner/GSA Latitude Longitude Reference Point Elevation (ft) Perforation Depths (ft bgs) CASGEM Well Frequency Representative Well Deep Zone Wells Antioch MW-90ǂ Antioch 38.01887 -121.819748 4.77 78-88 No daily* X 14 GNO BBID 37.889861 -121.642331 30.32 207-212, 229-238, 244- 253, 273-279, 349-356 Yes - Vol- untary monthly Brentwood MW-14 Deep CofB 37.9620001 -121.6957004 72.76 284-315 Yes monthly Brentwood MW-14 Int. CofB 37.9620001 -121.6957004 72.76 200-210, 220-230 Yes monthly X Bethel-Willow Rd DWD 38.045117 -121.639464 4.69 230-260 No semi-annual X Creekside MW DWD 37.9812138 -121.6911215 29.54 230-240 Yes monthly Diablo Water District-South Park DWD 37.9860934 -121.6330831 -3.5 204-264, 284-299 No monthly Glen Park MW DWD 37.9740743 -121.6866247 35.54 220-230, 260-290 Yes monthly Stonecreek MW-300 DWD 37.978122 -121.683968 30.47 230-240, 280-290 Yes monthly X Stonecreek MW-360 DWD 37.978122 -121.683968 30.7 340-350 Yes monthly Knightsen Community Water System-Well Head DWD 37.9709328 -121.6667157 29.911 235-255, 275-295 No monthly Knightsen Elementary School-Well 3 DWD 37.9679868 -121.6613267 29.59 395-415 No monthly Bethel Island (Sugar Barge Marina-Well Head) DWD 38.027155 -121.613661 -6 317-333 Yes monthly Well #14 (4-60A) ECCID 37.92526 -121.67739 55.5 200-330 No monthly 1BMW-343 TODB 37.9102996 -121.5993985 4.38 270-289, 309-338 Yes daily 4AMW-357 TODB 37.9009991 -121.6187989 11.54 307-347 Yes daily X 6MW-250 TODB 37.9028008 -121.5994988 6.6 200-210, 230-240 Yes daily 6MW-350 TODB 37.9028008 -121.5994988 6.6 280-290, 330-340 Yes daily 6MW-410 TODB 37.9028008 -121.5994988 6.54 390-400 Yes semi-annual Composite Wells Well 10A CofB 37.92166667 -121.7008333 91.85 52-72, 135-182 No monthly Well #4 Old (4-56) ECCID 37.9178 -121.697222 83.8 68-125, 175-195 Yes monthly Well #5 (4-57) ECCID 37.92526 -121.67722 60.9 115-125, 170-175, 195- 200, 220-245, 270-290 No monthly Blue indicates New Monitoring Well ǂWell installed August 2021 * New wells will be fitted with a SCADA system that will record water level measurements at least daily. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-9 A subset of wells in the basin-wide groundwater level monitoring network was selected for the representative groundwater level monitoring network. The representative wells are intended to represent regional conditions with respect to chronic lowering of groundwater levels (sustainability indicator) and for which minimum thresholds and measurable objectives are defined. The representative monitoring wells for groundwater levels are shown on Figure 6-2 for the Shallow Zone and Deep Zone, respectively. Table 6-3 identifies the representative monitoring wells which are a subset of the basin-wide wells. The representative monitoring wells were selected based on the following criteria: a. Show long term, regional trends (good historical record). b. Dedicated monitoring wells (no production wells). c. Known well construction features (construction date, well depth, perforation depths). d. Monitored monthly or continuously (i.e., with transducers and data loggers). e. Good horizontal and vertical spatial distribution. f. Greater number for high pumping areas (i.e., representative of conditions in vicinity of high municipal and agricultural pumpage). g. Professional judgment used where more than one suitable well is present. h. Include areas of domestic wells and disadvantaged communities. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-10 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-11 6.2.2.2. Spatial Density of Groundwater Level Monitoring Network The ECC Subbasin monitoring networks have a well density that exceeds recommended practices contained in Monitoring Networks and Identification of Data Gaps, Best Management Practices, (DWR, 2016). This BMP states that “the network should contain an adequate number of wells to observe the overall static conditions and the specific project effects.” It also states that there is no rule for the density of monitoring points but does provide a table of existing references (see Table 6-4, below) that lists density of monitoring wells per hundred square miles with ranges between 0.2 to 10 monitoring wells per 100 square miles. Given a maximum estimated ECC Subbasin groundwater pumping of approximately 14,000 af in the drought year of 2009 (12,700 af metered and 1,100 af unmetered), this converts to 8,300 acre-feet/year per 100 square miles resulting in about 2 monitoring wells per 100 square miles per the Hopkins (1984) guidance. Table 6-4. Groundwater Level Monitoring Well Density Considerations 2 For a subbasin area of approximately 168 square miles and with 55 basin-wide monitoring wells and 12 representative monitoring network wells, the ECC basin-wide and representative monitoring well densities are 33 wells per 100 square miles and 7 wells per 100 square miles, respectively (see Table 6-5, below). These well densities exceed the Sophocleous and Hopkins recommendations and exceed or falls within the Heath recommendations in the BMP technical guidance represented in Table 6-4, above. 2 Table 6-4 is a reproduction of Table 1 in the DWR BMP Monitoring Networks and Identification of Data Gaps. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-12 Table 6-5. ECC Subbasin Groundwater Level Monitoring Networks Density Monitoring Network No. of Wells Well Density (Wells per 100 square miles2 ) Basin-wide Monitoring Network 55 33 Representative Monitoring Network 12 7 6.2.2.3. Frequency and Timing of Groundwater Level Monitoring Groundwater elevation measurements will be made at a minimum of semi-annually to capture seasonal high and seasonal low levels. Historic groundwater monitoring data indicate that seasonal high elevations occur in winter to spring months (February-April) and seasonal low elevations occur in the fall (September-October). Table 6-3 includes the frequency of monitoring for each well in the basin-wide network. Historically through the present, chronic lowering of groundwater levels has not been observed in the ECC Subbasin; however, if conditions change in the future, the semi-annual monitoring frequency will be reevaluated to ensure that monitoring of this sustainability indicator complies with SGMA regulations. 6.2.2.4. Groundwater Level Data Gaps The existing ECC groundwater level monitoring network is sufficient to monitor areas near the major municipal pumping. However, data gaps were identified in areas where groundwater pumping is limited to only domestic and small water systems. Additional Shallow Zone wells will be installed to accomplish the following objectives: • Increase density of groundwater level monitoring wells. • Provide information on surface water and groundwater interaction and conditions near groundwater dependent ecosystems (GDEs). • Provide information on boundary conditions. • Ensure that long-term monitoring results are consistent and reliable. • Improve understanding of impact of groundwater management to beneficial users. • Improve characterization of groundwater flow regimes. 6.2.2.5. Plan to Fill Groundwater Level Data Gaps The installation and instrumentation of 9 Shallow Zone groundwater level monitoring wells at four sites are planned as part of the preparation of this GSP and will be implemented under a Proposition 68 grant from DWR. Figure 6-3 shows the new monitoring wells and existing Shallow Zone monitoring network in relation to other beneficial users of groundwater in the ECC Subbasin: Disadvantaged Areas, small public water systems, GDEs, and de minimis users (domestic well owners). These beneficial users were considered in siting the new monitoring wells. Figure 6-1b shows the deep monitoring well network in relation to the one new deep zone monitoring well location (Antioch) and areas of larger-scale pumping by municipal and agricultural users. The following Table 6-6 lists the data gaps filled by each new well. The new monitoring wells will increase the density of the groundwater level monitoring network and enhance coverage of groundwater level data. It is recognized that additional data gaps may become evident during and after GSP implementation. As supported by data from the monitoring networks, such data gaps will be filled to ensure sustainable management of the Subbasin. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-13 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-14 Table 6-6. Proposed New Monitoring Wells to Fill Data Gaps Data Gap Antioch1 Shallow/Deep Bethel Island2 Shallow TODB3 Shallow CCC/CCWD Shallow Climate Change: Monitor Sea Level Rise, Increase in Chloride/TDS x x Expand Shallow Zone Network x x x x Expand Deep Zone Network x Groundwater Quality x (esp. Cl and TDS) x (esp. Cl and TDS) x x Near GDEs and Monitors for Shallow Groundwater/Surface Water Interaction. x x x x Located near Small Public Water Systems and Domestic Wells x x Located near Disadvantaged Areas x x Adjacent to Municipal Well Pumping x Subbasin Boundary Conditions x x x Construction: Perforations (ft bgs) 10-15, 20-30, 85-95 5-10, 20-30 10-15, 20-30 5-15, 25-35 1. City of Antioch does not pump groundwater for municipal supply. Domestic supply source is surface water only. 2. Bethel Island is served by public water systems and domestic wells. 3. TODB pumps only groundwater for municipal supply. 6.2.3. Groundwater Quality Monitoring Network The groundwater quality monitoring network includes municipal production wells that report groundwater quality as regulated by the State Division of Drinking Water under Drinking Water Programs. The objectives of the groundwater quality monitoring program for the ECC Subbasin include the following: • Evaluate and determined a baseline of groundwater quality conditions in both Shallow Zone and Deep Zone aquifers in the Subbasin and in areas of higher groundwater use. • Assess changes and trends in groundwater quality (seasonal, short- and long-term trends). • Incorporate existing groundwater quality monitoring programs (i.e., monitoring of Public Water Systems under the state Drinking Water Programs). • Provide means to assess groundwater quality impacts to beneficial uses and users including but not limited to effects on primary and secondary drinking water standards for domestic users, crop suitability for agricultural users, and groundwater dependent ecosystems. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-15 • Identify natural (e.g., climate change) and anthropogenic factors that affect groundwater quality including the potential for mobilization of contamination through groundwater flow patterns that may be altered by sustainable management activities. This section describes the basin-wide and representative monitoring networks, monitoring frequency, spatial density, and monitoring protocols for the degraded groundwater quality sustainability indicator. The monitoring networks are enumerated in Table 6-7, below. As discussed in Section 7, only representative monitoring wells are used to determine compliance with minimum thresholds or measurable objectives for the degraded water quality sustainability indicator. Table 6-7. GSA Groundwater Quality Monitoring Network GSA Number of Wells Basin-Wide Network Total Representative Monitoring Network Existing Monitoring Wells New Monitoring Wells Production Wells Total Basin- Wide BBID City of Antioch 2 2 2 City of Brentwood 1 8 9 3 Contra Costa County/CCWD 1 1 1 Diablo Water District 1 1 2 4 3 Town of Discovery Bay 1 5 6 2 ECCID Total 2 5 15 22 11 Note: Multiple completion monitoring wells are counted as separate wells for each depth. 6.2.3.1. Basin-wide Groundwater Quality Monitoring Network The Basin-wide groundwater quality monitoring network is summarized in Table 6-7. Details of the basin- wide monitoring network are provided in Table 6-8 including well name, owner, perforation depths, and monitoring frequency. The wells are grouped according to aquifer zone (Shallow Zone and Deep Zone). The network consists of consists of 22 wells of which 5 are completed in the Shallow Zone and 17 in the Deep Zone. The Shallow Zone and Deep Zone well locations are shown on Figure 6-4. Other agencies track groundwater contamination including GeoTracker (online resource). Section 3.3.6 discusses the groundwater contamination sites in the ECC Subbasin and Appendix 3h lists the 35 open sites and the 105 closed sites in the Subbasin. The lists and locations will be updated to identify any changes in plume movement EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-16 Table 6-8. Basin-wide and Representative Groundwater Quality Monitoring Network Local Well Name Owner/ GSA Perforation Data: First Date Data: Last Date Frequency Seawater Intrusion Monitoring Network Representative Monitoring Wells Shallow Zone BG-1 Brentwood 40-55 2/17/2008 2/15/2015 Annual1 x Antioch MW-15ǂ Antioch 5-15 Annual1 x x DWD MW-30ǂ DWD 20-30 Annual1 x x TODB MW-30 TODB 20-30 Annual1 x x New Well Old River 1 of 2 CCC/CCWD Annual1 x x Deep Zone Antioch MW-90ǂ Antioch 78-88 Annual1 x City of Brentwood-Well 06 Brentwood 250-300 8/16/1990 8/7/2019 Variable2 City of Brentwood-Well 07 Brentwood 265-295 5/5/1988 5/6/2019 Variable2 City of Brentwood-Well 08 Brentwood 225-315 6/14/1993 5/6/2019 Variable2 City of Brentwood-Well 09 Brentwood 210-230 7/19/2004 6/1/2016 Variable2 City of Brentwood-Well 12 Brentwood 350-380, 430-450 12/18/1997 6/1/2016 Variable2 City of Brentwood-Well 13 Brentwood 350-380, 430-480 12/17/1997 5/9/2019 Variable2 x City of Brentwood-Well 14 Brentwood 285-315 11/3/2000 5/9/2019 Variable2 x City of Brentwood-Well 15 Brentwood 239-259 289-324 7/26/2006 12/9/2019 Variable2 Glen Park Well DWD 230-245, 260-300 5/4/2004 6/19/2019 Variable2 x Stonecreek Well DWD 220-295 5/10/2010 6/19/2019 Variable2 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-17 Local Well Name Owner/ GSA Perforation Data: First Date Data: Last Date Frequency Seawater Intrusion Monitoring Network Representative Monitoring Wells Bethel-Willow Rd DWD 230-260 Annual1 x Town of Discovery Bay Well 1B TODB 271-289, 308-340 3/28/1995 5/23/2019 Variable2 Town of Discovery Bay Well 2 TODB 245-335 11/19/1986 5/23/2019 Variable2 Town of Discovery Bay Well 4A TODB 307-347 8/1/1996 5/23/2019 Variable2 x Town of Discovery Bay-Well 06 TODB 270-295, 305-350 8/24/2009 5/23/2019 Variable2 Town of Discovery Bay-Well 07 TODB 282-292 7/30/2015 7/9/2019 Variable2 Blue indicates New Monitoring Well ǂ Well installed August 2021 1. Sampling frequency is annual for first five years at which time it will be evaluated and potentially changed to align with typical compliance monitoring (e.g., 3 or 5 years depending on constituent). 2. Variable as per current compliance monitoring under state drinking water programs. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-18 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-19 6.2.3.2. Representative Groundwater Quality Monitoring Network The representative monitoring network for the Shallow Zone is the same as the Basin-wide monitoring network (see Figure 6-4). The Deep Zone representative monitoring network is a subset of the Basin-wide Monitoring Network and consists of 4 existing wells in the zones of municipal pumping plus one new well (Antioch) and an existing deep well on Bethel Island (DWD) that are both areas of data gaps discussed under groundwater level monitoring (see Figure 6-5). Table 6-8 lists features of the representative monitoring wells in both Shallow Zone and Deep Zone aquifers. For the Deep Zone, the selected representative wells in areas of high production are municipal wells that are completed solely in the deep aquifer zone and for which historical and ongoing water quality testing data are available. 6.2.3.3. Spatial Density, Frequency, and Data Gaps of Groundwater Quality Monitoring Network Monitoring wells are distributed in both principal aquifer zones in the ECC Subbasin. Monitoring in the Deep Zone aquifer is focused on areas of highest groundwater production plus data gap areas in Antioch and on Bethel Island (see Figure 6-5). Sampling frequency will be consistent with typical compliance monitoring for municipal wells to provide sufficient data to evaluate groundwater quality trends over time in each aquifer zone. No additional monitoring wells are required at this time and the network will be reevaluated for the 5-year report. The groundwater quality monitoring network may be expanded if any of the following occurs: changes to groundwater quality restricting beneficial use, increase in groundwater development and/or shifts in pumping patterns, or if there is a change in groundwater management actions or projects. In such cases, the need to adapt monitoring frequency and/or sites shall be determined from the monitoring record. 6.2.4. Seawater Intrusion Monitoring Network The seawater intrusion monitoring network is designed to address a mechanism by which Delta baywater migrates into shallow groundwater (see discussion in Section 3.3.4). The potential for intrusion of saline water into the shallow zone may be exacerbated by sea level rise. These intrusion mechanisms could impact groundwater sustainability if saline water in the Shallow Zone migrated vertically into the Deep Zone supply source. At present, there is no evidence that saline intrusion from Delta baywaters has occurred or adversely affected groundwater resources in the ECC Subbasin. The sustainability indicator for Seawater Intrusion (baywater for this Subbasin) is evaluated using a chloride concentration map that will include a new dedicated Shallow Zone monitoring wells that will act as sentinels for baywater intrusion and degradation. Table 6-8 lists the Shallow and Deep Zone Wells used to monitor chloride concentration and Figure 6-5 shows the locations of these wells. There is currently no Shallow Zone chloride concentration contour map since the four new monitoring well results are not yet available to provide the necessary well control. However, Figure 3-16d shows the average chloride (2008 to 2018) concentration in all Shallow Zone and Deep Zone wells. Seawater Intrusion Monitoring Protocols are the same as for those used for groundwater quality (Appendix 6a). Chloride concentration contour intervals will be based on the ranges of recorded values, well control, and analytic considerations. Seawater Intrusion Monitoring Data Gap: Currently there is no historic seawater intrusion in the Subbasin. The four new shallow monitoring well pairs will serve as sentinels and inform on the need for expanded monitoring at other locations. As data is collected and analyzed and if conditions change, additional wells can be installed with consideration of spatial and vertical control. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-20 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-21 6.2.5. Land Subsidence Monitoring Network The ECC Subbasin is not a locus for inelastic land subsidence due to groundwater extraction. This is a result of stable historic groundwater levels and lack of subsurface lithologies that would be susceptible to subsidence. However, the sustainability indicator for land subsidence will be monitored through an existing network as discussed below. The existing land subsidence monitoring network applicable to the ECC Subbasin is comprised of four Plate Boundary Observatory (PBO) (see Figure 6-6) Stations. Details about the PBO network are presented in Section 3.3.7. PBO Station 256 is located within the ECC Subbasin and three others, P230, P248 and P257, are located in the same region but outside the Subbasin boundary. DWR has also published Interferometric Synthetic Aperture Radar (InSAR) results in partnership with the European Space Agency’s Sentinel-1A satellite with the data processed by TRE ALTAMIRA 3. These data present measurements of vertical ground surface displacement between two different dates. InSAR mapping of land surface elevation is particularly useful for complementing high spatial and temporal resolution data at CGPS station locations with observations of land subsidence over a large area for highlighting locations where change is occurring. The representative monitoring network consists of Station 256 (P256). While land subsidence network spatial density recommendations are not provided in DWR technical guidance documents, the use of data from P256 is considered sufficient based on the lack of historical subsidence and lack of lithologies generally associated with subsidence caused by pumping. InSAR has been made available for the Subbasin and will provide coverage for the entire Subbasin and be used to compare results from the Station 256. In addition, the groundwater level monitoring will serve as a proxy to assess the sufficiency of the subsidence monitoring networks. Data from PBO Station 256 and InSAR will be reviewed annually. The land subsidence networks will be evaluated as part of the 5-year update and if there is evidence of subsidence at that time, additional monitoring will be considered. 3 https://gis.water.ca.gov/arcgisimg/rest/services/SAR EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-22 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-23 6.2.6. Interconnected Surface Water Monitoring Network The Monitoring Networks and Identification of Data Gaps BPM (DWR, 2016) states that an interconnected surface water and groundwater network should include stream gages and groundwater level monitoring in areas where there is a known surface water groundwater connection. These data are then used to estimate depletions. The interconnected surface water monitoring network for the ECC Subbasin consists of a subset of 15 Shallow Zone groundwater level monitoring network wells that are located adjacent to creeks, rivers and GDEs along with existing surface water flow monitoring stations (see Figure 6-7 and Table 6-9). There are 19 surface water monitoring sites in the Subbasin or in the vicinity of the Subbasin boundary. These stations are independently or jointly operated by Contra Costa County Flood Control and Water Conservation District, DWR, and USGS. Most of the surface water monitoring stations at locations adjacent to the San Joaquin River, Old River, Middle River, Marsh Creek, and water conveying canals. Flow data collected at these stations (stage and/or flow rate) are publicly available. There is a range of historical data associated with these stations providing an ability to develop historical baselines to compare with future monitoring results. A representative monitoring network is not necessary because the groundwater level monitoring network serves as a proxy for depletion of interconnected surface water. Surface water monitoring protocols are established by the monitoring entity (DWR and USGS in most cases). Spatial density for interconnected surface water monitoring networks is not specified in the Monitoring Networks and Identification of Data Gaps BMP (DWR, 2016), the incorporation of the active stations is considered sufficient for GSP implementation based on professional judgement. The special coverage for this initial GSP will be evaluated in the 5-year GSP update. Currently there is an incomplete understanding of the interconnected surface water systems in the Subbasin. This is expected to be remedied through installation of shallow multiple completion monitoring wells (eight wells at four sites as part of this GSP) and future monitoring efforts related to this GSP. 6.2.6.1. Groundwater Dependent Ecosystem Monitoring GSP Regulations do not require the monitoring of GDEs in a GSP, however, GDEs must be properly identified within the Plan area utilizing data available from DWR, as specified in GSP Regulation §353.2, or the best information available to the Agency. The subbasin will annually review remote sensing to monitor the health of GDEs. Landsat imagery is available at a resolution of 30 meters every 16 days, from which long-term temporal trends of vegetation metrics can be assessed on The Nature Conservatory’s (TNC) GDE Pulse web app, allowing users to infer the relationships between groundwater levels, precipitation, and GDE vegetation metrics. As detailed on the GDE Pulse website, the methods in which TNC processed the satellite data results in a geospatial representation of the Normalized Derived Vegetation Index (NDVI) to estimate vegetation greenness and Normalized Derived Moisture Index (NDMI) to estimate vegetation moisture. TNC provides the average NDVI and NDMI for all Landsat pixels, masked to spatial data from the iGDE database, to present the average and trend geospatial layers representing positive and negative trends in the two-vegetation metrics. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-24 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-25 Figure 6-Table 6-9. Basin-wide Interconnected Surface Water Monitoring Network Station Name CDEC Code Monitoring Entity Monitoring Frequency San Joaquin River at Antioch ANH CA Dept of Water Resources Hourly Bacon Island at Old River BAC CA Dept of Water Resources Hourly Old River at Coney Island CIS CA Dept of Water Resources 15 minutes Discovery Bay at Discovery Bay Blvd DBD CA Dept of Water Resources Hourly Discovery Bay at Indian Slough DBI CA Dept of Water Resources Hourly Dutch Slough At Jersey Island DSJ US Geological Survey 15 minutes False River Near Oakley FAL US Geological Survey and CA Dept of Water Resources 15 minutes Fishermans Cut FCT CA Dept of Water Resources 15 minutes Holland Cut Near Bethel Island HOL US Geological Survey and CA Dept of Water Resources Hourly Italian Slough Headwater Nr Byron ISH CA Dept of Water Resources 15 minutes Marsh Creek at Brentwood MBW Contra Costa County Flood Control and Water Conservation District 15 minutes Marsh Creek at Dainty Blvd MDA Contra Costa County Flood Control and Water Conservation District 15 minutes Old River at Bacon Island (USGS) OBI 4 US Geological Survey and CA Dept of Water Resources Hourly Old River at Byron ORB CA Dept of Water Resources 15 minutes Old River at Clifton Court Intake ORI CA Dept of Water Resources 15 minutes Old River at Quimbly Is Near Bethel Is ORQ US Geological Survey and CA Dept of Water Resources 15 minutes Old River at Franks Tract Near Terminus OSJ US Geological Survey and CA Dept of Water Resources hourly Rock Slough Abv Contra Costa Canal RSL CA Dept of Water Resources 15 minutes San Joaquin River at Jersey Point (USGS) SJJ US Geological Survey 15 minutes Three Mile Slough at San Joaquin River SR3 CA Dept of Water Resources 15 minutes West Canal at Clifton Court Intake WCI CA Dept of Water Resources 15 minutes 4 Same as Bacon Island at Old River (BAC). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-26 6.3. Protocols for Data Collection and Monitoring (§ 352.2) The GSP monitoring protocols are consistent with the Groundwater Monitoring Protocols, Standards, and Sites Best Management Practice (DWR, 2016). The recommended monitoring protocols were adapted based on experience of the ECC GSAs with the final protocols meeting or exceeding the recommendations in the BMP guidance document. Monitoring protocols for groundwater pumping were not given in the BMP document but accounting for groundwater pumping is an important part of managing sustainability in the ECC Subbasin. Therefore, monitoring protocols for measuring groundwater pumping are included in this GSP. The monitoring protocols that are described in Appendix 6a will provide the necessary data to track minimum thresholds and measurable objectives for each sustainability indicator. The monitoring protocols established here are to be reviewed in 5 years as a part of periodic review of the GSP. The following protocols shall be employed at all monitoring sites: • Document basic information for each monitoring point: a unique identifier, a description of the site location, geographical coordinates, elevation, date established, access instructions, and type(s) of data to be collected. o A modification log shall be to be kept in order to track all modifications to the monitoring site. • Locations shall be reported in geographical coordinates to a minimum accuracy of 30 feet or relative to the North American Datum of 1983 (NAD83). • Reference point elevations shall be measured in feet to an accuracy of at least 0.5 feet relative to the North American Vertical Datum of 1988 (NAVD 88). 6.4. Data Gaps The ECC Subbasin monitoring networks consists of groundwater monitoring wells, stream gages and subsidence monitoring stations. The networks will be integrated into the GSP to monitor hydrological conditions for six SGMA sustainability indicators. The number of groundwater monitoring wells in the ECC Subbasin networks exceeds the minimum number of wells recommended in the DWR BMP technical guidance. As per the method developed by Hopkins (1984) and included in the BMP, a basin that pumps groundwater between 1,000 and 10,000 AFY per 100 square miles should have two monitoring wells. The ECC Subbasin has four monitoring wells and a maximum historical annual groundwater pumpage of approximately 14,000 AF (12,700 af metered and 1,100 af non-metered). When prorated to the Subbasin area of 168 square miles, pumpage is 8,300 af and the number of wells is 2.4 per 100 square miles thus satisfying the Hopkins (1984) criterion for a basin that pumps between 1,000 and 10,000 AFY per 100 square miles. Groundwater pumping and usage vary between the seven GSAs in the ECC Subbasin. As a result, the monitoring network was designed to provide a higher density of monitoring sites in areas where groundwater pumping is high, while providing a sufficient spatial coverage throughout the Subbasin. The monitoring schedule for each sustainability indicator was developed to utilize existing monitoring programs while ensuring that relevant seasonal, short-term, and long-term trends are captured. The monitoring sites meet the standards described in GSP Regulations § 352.4. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-27 The rationales for selection of groundwater monitoring wells were their construction (penetrate only one aquifer zone), location relative to the Subbasin boundary, groundwater pumping wells and surface water features, being affiliated with current monitoring programs, and availability of historical data. Subsidence and surface water monitoring stations were selected based on their locations and availability of data. Data gaps have been initially evaluated and filled with new monitoring wells to be installed prior to implementation of the GSP. To the extent that other data gaps become evident through evaluation of hydrologic conditions and have the potential to impair sustainable groundwater management, additional wells shall be proposed and assessed to add to the networks. 6.4.1. Well Inventory Data Gap To date, there have been no comprehensive efforts or procedures instituted to inventory active production wells in the ECC Subbasin. With the implementation of this GSP, a well inventory program shall be created with completion targeted for the 5-year Plan update. The well inventory will be developed as a tool to better understand how management of the Subbasin affects groundwater users should adverse impacts occur. The process of creating a well inventory will be coordinated with the Contra Costa County Environmental Health Division which is the permitting agency for new wells in the ECC Subbasin. A procedure for sharing information on all new wells constructed under the County’s permitting authority with the ECC Subbasin Data Management System shall be developed. The well inventory system will track various parameters including the following: • Well location and GIS coordinates • Date installed • Permit number (County) • Well Drillers Report number (DWR) • Depth of well • Well diameter • Depths of perforations • Use (domestic, industrial, commercial, agricultural, other) A method to incorporate wells constructed prior to the new data exchange system is implemented will be evaluated with the objective that the DMS substantially accounts for active wells that serves sustainable management goal of the Subbasin as detailed in Section 7, Sustainable Management Criteria. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-28 6.5. Ongoing Monitoring Network Evaluation Monitoring network of the ECC GSP was established based on the ability to adequately monitor each sustainability indicator while utilizing all available monitoring sites. Each 5-year update of the GSP will include an analysis of the existing monitoring network and its ability to accurately characterize conditions and achieve sustainability. One data gap that has been currently identified is the monitoring of interconnected surface water, and it will be addressed before the next GSP update. The monitoring network will be evaluated and potentially updated under any of the following conditions before a 5-year update: • Exceedance of minimum threshold of a sustainability indicator. • Highly variable spatial or temporal conditions that are inconsistent with historical baselines and the hydrogeological conceptual model. • Adverse impacts to beneficial uses and users of groundwater. • Determination of potential adverse effects on the ability of an adjacent basin to implement a GSP or impede achievement of sustainability goals in that basin. 6.6. Groundwater Data Management The GSAs in the ECC Subbasin will measure the groundwater levels of wells according to the monitoring protocols set forth in the GSP Appendix 6a. Water level data will be submitted to a designated GSA or directly to a database manager for the GSP. Groundwater quality samples will be collected by GSAs and sent for analysis by a certified laboratory per local practice. Quantitative testing results shall be submitted either to the designated GSA or directly to the GSP database manager. The database manager will annually transmit to the GSAs hydrographs for wells, analytical plots, brief overview of data and field reports. Groundwater levels of the wells that are in the CASGEM network are typically collected in mid-March and mid-October of each year. All semi-annual data is sent to the database manager for review and uploading to the DWR website by March 31 (spring data) and October 31 (fall data). The database manager will upload the data according to procedures specified by DWR. In accordance with GSP Regulation §354.4, copies of monitoring data stored in the DMS shall be included in annual reports and submitted electronically on forms provided by DWR. The ECC GSAs have established guidelines to ensure that data are managed according to permissions granted by each well owner and/or as relating to applicable permit conditions. 6.7. Data Management System (§ 352.6) In accordance with GSP Regulation § 352.6, the ECC Subbasin Data Management System (DMS) has been developed to incorporate existing and new data related to groundwater resources in the Subbasin. Site- specific information for monitoring points (identification, owner, location, construction details, measurement types, measurement method, measurement frequency, affiliated monitoring programs, permission, and other comments) and time series data shall be securely stored and backed-up in the DMS. The DMS is also capable of processing data and producing reports to meet the reporting requirements under GSP implementation. The current DMS platform is Microsoft Access and the database manager can control the access to data by DMS users. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 6 - MONITORING NETWORK AND DATA MANAGEMENT SYSTEM LSCE 6-29 6.8. Data Use and Disclosure Some wells in the monitoring network are privately-owned. Monitoring and data reporting associated with those wells are conducted with the permission of well owners. Exact location information of private wells will be redacted from submittals, while water level and quality data will be published with the well owner’s permission. Groundwater quality of public supply wells will be publicly available. 6.9. Data Submittals Monitoring data will be submitted to DWR in electronic formats utilizing the forms provided by the DWR (GSP Reg. § 353.4). 6.10. Reporting Annual reporting and periodic evaluation for the ECC GSP monitoring networks are detailed in Section 9. 6.11. References California Department of Water Resources (DWR). December 2016. Guidance Document for the Sustainable Management of Groundwater: Monitoring Networks and Identification of Data Gaps, Best Management Practice. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-i SECTION 7 CONTENTS 7. Sustainable Management Criteria ............................................................................................7-1 7.1. Process to Establish Sustainable Management Criteria............................................................. 7-3 7.2. ECC Sustainability Goal .............................................................................................................. 7-4 7.2.1. Goal Description ................................................................................................................. 7-4 7.2.2. Historical, Existing and Potential Future Conditions of Undesirable Results..................... 7-5 7.2.3. Measures to be Implemented ............................................................................................ 7-5 7.2.4. Explanation of How the Sustainability Goal will be Achieved ........................................... 7-5 7.2.4.1. Projects ...................................................................................................................... 7-6 7.2.4.2. Management Actions ................................................................................................. 7-6 7.3. ECC Sustainability Indicators ...................................................................................................... 7-6 7.3.1. Chronic Lowering of Groundwater Levels .......................................................................... 7-7 7.3.1.1. Undesirable Results .................................................................................................... 7-7 7.3.1.2. Criteria to Define Undesirable Results ....................................................................... 7-7 7.3.1.3. Potential Causes of Undesirable Results .................................................................... 7-8 7.3.1.4. Potential Effects of Undesirable Results .................................................................... 7-8 7.3.1.5. Minimum Thresholds ................................................................................................. 7-8 7.3.1.6. Information and Criteria Relied Upon to Establish the Minimum Threshold .......... 7-10 7.3.1.7. The Relationship of Minimum Thresholds for Other Sustainability Indicators........ 7-13 7.3.1.8. How the MT was Selected to Avoid Causing Undesirable Results in Adjacent Basins .. 7-14 7.3.1.9. How the MT may Affect the Interests of Beneficial Uses and Users of Groundwater .. 7-14 7.3.1.10. How the MT Relates to the Federal, State, or Local Standards ............................... 7-15 7.3.1.11. How each MT will be Quantitatively Measured ....................................................... 7-15 7.3.1.12. Measurable Objectives and Interim Milestones ...................................................... 7-15 7.3.2. Reduction in Groundwater Storage ................................................................................. 7-17 7.3.2.1. Undesirable Results .................................................................................................. 7-17 7.3.2.2. Criteria to Define Undesirable Results ..................................................................... 7-17 7.3.2.3. Potential Causes of Undesirable Results .................................................................. 7-18 7.3.2.4. Potential Effects of Undesirable Results .................................................................. 7-18 7.3.2.5. Minimum Thresholds ............................................................................................... 7-18 7.3.2.6. Measurable Objectives and Interim Milestones ...................................................... 7-18 7.3.3. Seawater Intrusion ........................................................................................................... 7-18 7.3.3.1. Undesirable Results .................................................................................................. 7-19 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-ii 7.3.3.2. Criteria to Define Undesirable Results ..................................................................... 7-19 7.3.3.3. Potential Causes of Undesirable Results .................................................................. 7-19 7.3.3.4. Potential Effects of Undesirable Results .................................................................. 7-20 7.3.3.5. Minimum Thresholds ............................................................................................... 7-20 7.3.3.6. Information and Criteria Relied Upon to Establish the Minimum Threshold .......... 7-21 7.3.3.7. The Relationship of Minimum Thresholds for Other Sustainability Indicators........ 7-21 7.3.3.8. How the MT was Selected to Avoid Causing Undesirable Results in Adjacent Basins .............................................................................................................................................. 7-21 7.3.3.9. How the MT may Affect the Interests of Beneficial Uses and Users of Groundwater ....................................................................................................................................... 7-22 7.3.3.10. How the MT Relates to the Federal, State, or Local Standards ............................... 7-22 7.3.3.11. How Each MT Will be Quantitatively Measured ...................................................... 7-22 7.3.3.12. Measurable Objectives and Interim Milestones ...................................................... 7-22 7.3.4. Degraded Water Quality .................................................................................................. 7-23 7.3.4.1. Undesirable Results .................................................................................................. 7-23 7.3.4.2. Criteria to Define Undesirable Results ..................................................................... 7-23 7.3.4.3. Potential Causes of Undesirable Results .................................................................. 7-24 7.3.4.4. Potential Effects of Undesirable Results .................................................................. 7-24 7.3.4.5. Minimum Thresholds ............................................................................................... 7-24 7.3.4.6. Information Used and Methodology ....................................................................... 7-24 7.3.4.7. Degraded Groundwater Quality Minimum Thresholds ........................................... 7-25 7.3.4.8. The Relationship of Minimum Thresholds between Like and Different Sustainability Indicators .................................................................................................................. 7-25 7.3.4.9. How the MT was Selected to Avoid Causing Undesirable Results in Adjacent Basins ... 7-26 7.3.4.10. How the MT May Affect the Interests of Beneficial Uses and Users of Groundwater .. 7-26 7.3.4.11. How the MT Relates to the Federal, State, or Local Standards ............................... 7-27 7.3.4.12. How Each MT Will be Quantitatively Measured ...................................................... 7-27 7.3.4.13. Measurable Objectives and Interim Milestones ...................................................... 7-27 7.3.5. Land Subsidence............................................................................................................... 7-28 7.3.5.1. Undesirable Results .................................................................................................. 7-28 7.3.5.2. Criteria to Define Undesirable Results ..................................................................... 7-29 7.3.5.3. Potential Causes of Undesirable Results .................................................................. 7-29 7.3.5.4. Potential Effects of Undesirable Results .................................................................. 7-29 7.3.5.5. Minimum Thresholds ............................................................................................... 7-29 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-iii 7.3.5.6. Information and Criteria Relied Upon to Establish the Minimum Threshold .......... 7-30 7.3.5.7. The Relationship of Minimum Thresholds between Like and Different Sustainability Indicators ............................................................................................... 7-31 7.3.5.8. How the MT was Selected to Avoid Causing Undesirable Results in AdjacentBasins .. 7-31 7.3.5.9. How the MT May Affect the Interests of Beneficial Uses and Users of Groundwater .. 7-31 7.3.5.10. How the MT Relates to the Federal, State, or Local Standards ............................... 7-31 7.3.5.11. How Each MT Will be Quantitatively Measured ...................................................... 7-32 7.3.5.12. Measurable Objectives and Interim Milestones ...................................................... 7-32 7.3.6. Depletions of Interconnected Surface Waters ................................................................ 7-32 7.3.6.1. Undesirable Results .................................................................................................. 7-32 7.3.6.2. Criteria to Define Undesirable Results ..................................................................... 7-33 7.3.6.3. Potential Causes of Undesirable Results .................................................................. 7-33 7.3.6.4. Potential Effects of Undesirable Results .................................................................. 7-33 7.3.6.5. Minimum Thresholds ............................................................................................... 7-33 7.3.6.6. Information and Criteria Relied Upon to Establish the Minimum Threshold .......... 7-34 7.3.6.7. How the MT May Affect the Interests of Beneficial Uses and Users of Groundwater .. 7-35 7.3.6.8. The Relationship of Minimum Thresholds for Other Sustainability Indicators........ 7-35 7.3.6.9. How the MT was Selected to Avoid Causing Undesirable Results in Adjacent Basins 7-35 7.3.6.10. How the MT Relates to the Federal, State, or Local Standards ............................... 7-36 7.3.6.11. How Each MT Will be Quantitatively Measured ...................................................... 7-36 7.3.6.12. Measurable Objectives ............................................................................................ 7-36 7.4. References ............................................................................................................................... 7-37 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-iv LIST OF TABLES Table 7-1 Summary of Undesirable Results Applicable to the Plan Area……………….……….……………7-5 Table 7-2 Minimum Thresholds, Measurable Objectives, and Interim Milestones for Chronic Lowering of Groundwater Levels.…………………………………….………………………………………….7-10 Table 7-3 Constituents of Concern for Groundwater Quality Minimum Threshold.…….…………….7-25 Table 7-4 Minimum Thresholds, Measurable Objectives, and Interim Milestones for Degradation of Groundwater Quality…………………………………………………………………………7-28 LIST OF FIGURES Figure 7-1 Relationship between Sustainability Indicators, Minimum Thresholds, and Undesirable Results…………………………………………………………………………………………………………………………7-2 Figure 7-2 Sustainability Management Criteria Example-Groundwater Levels………………………………7-3 Figure 7-3 Top of Well Perforations for Domestic Wells by Section…………………………..……………….7-12 Figure 7-4 Measurable Objectives and Minimum Thresholds – TODB Production Wells……….……7-16 APPENDICES Appendix 7a Representative Monitoring Sites Minimum Threshold, Measurable Objectives for Chronic Lowering of Groundwater Levels Appendix 7b Comparison of Domestic Wells and Depth to Minimum Threshold EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-1 7. SUSTAINABLE MANAGEMENT CRITERIA Sustainable groundwater management is the management and use of groundwater in a manner that can be maintained for the next 50 years without causing undesirable results 1. The avoidance of undesirable results is critical to the success of a Groundwater Sustainability Plan (GSP). Management of the basin through this GSP will be conducted using the best available science and it will be periodically updated through an adaptive process in response to various factors including climate change. Consistent with the principles described above, the East Contra Costa (ECC) GSP has tailored sustainable management criteria (SMC) specific to the conditions found in the ECC Subbasin. The development and implementation of these SMCs, (e.g., sustainability goal, undesirable results, minimum thresholds, and measurable objectives 2) ensures the continued sustainability of groundwater resources in the ECC Subbasin by committing the seven overlying GSAs to future management actions. This section defines sustainable management criteria for the ECC Subbasin including the data and methods used in their development and how they relate to beneficial uses and users of groundwater. The SMC are based on current available data and analyses of the basin setting and groundwater conditions as detailed in (Section 3). GSP regulations require that sustainable management criteria be developed for each sustainability indicator (note that the seawater intrusion indicator is characterized in the ECC Subbasin as significant and unreasonable intrusion of Delta and Bay waters): • Chronic lowering of groundwater Levels • Reduction of storage (ECC Subbasin GSP uses proxy of groundwater levels) • Seawater intrusion • Degraded water quality • Land subsidence • Depletion of interconnected surface water (ECC Subbasin GSP uses proxy of groundwater levels) The Department of Water Resources prepared a Best Management Practice document3 to assist GSAs in developing SMC and that defines the terminology used in the section. Figure 7-1 illustrates the relationship between sustainability indicators, minimum thresholds, and undesirable results. For reference during the review process only, 1 California Water Code 10721 (v) and (r) 2 23 CCR Groundwater Sustainability Plans § 354.22 et seq. 3 BMP 6 Sustainable Management Criteria Best Management Practice https://water.ca.gov/Programs/Groundwater- Management/SGMA-Groundwater-Management/Best-Management-Practices-and-Guidance-Documents EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-2 Figure 7-1. Relationship between Sustainability Indicators, Minimum Thresholds, and Undesirable Results EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-3 Figure 7-2. Sustainability Management Criteria Example-Groundwater Levels The SMC developed for the ECC Subbasin were coordinated by the seven overlying GSAs, (City of Antioch and Brentwood, Byron Bethany Irrigation District, Contra Costa County, Diablo Water District, East Contra Costa Irrigation District, Town of Discovery Bay) and CCWD via an agreement to prepare a single GSP. SMC development was informed by hydrologic and hydrogeologic analyses leading to the ECC Hydrogeologic Conceptual Model presented in Section 3, Basin Setting. The process for establishing SMC included: • GSA Working Group meetings. • Public meetings on GSP development that introduced stakeholders to SMC. • Additional public meetings on proposed methodologies to establish minimum thresholds and measurable objectives to receive additional public input. • Public surveys to receive additional stakeholder input. • Review of public input on preliminary SMC methodologies with GSA staff/technical experts. • Preparation of a Draft GSP for public review and comment. • Establishing and modifying minimum thresholds, measurable objectives, and definition of undesirable results based on feedback from public meetings, public/stakeholder review of the Draft GSP, and input from GSA staff/technical experts. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-4 7.2. ECC Sustainability Goal 7.2.1. Goal Description The ECC Subbasin is not experiencing undesirable results as defined under SGMA. The sustainability goal for the ECC Subbasin GSP is to manage the groundwater Subbasin to: • Protect and maintain safe and reliable sources of groundwater for all beneficial uses and users. • Ensure current and future groundwater demands account for changing groundwater conditions due to climate change. • Establish and protect sustainable yield for the Subbasin by achieving measurable objectives set forth in this GSP in accordance with implementation and planning periods 4. • Avoid undesirable results defined under SGMA. The GSAs in the ECC Subbasin will manage the Subbasin under a single GSP. The GSAs and other water agencies have cooperatively engaged in water supply issues in the Subbasin including Integrated Regional Water Management plans, groundwater management plans, and California Statewide Groundwater Elevation Monitoring (CASGEM) monitoring. Through coordinating agreements, the GSAs will continue to manage the ECC Subbasin while retaining groundwater management authority within their respective jurisdictions. The following principles are incorporated into the GSP to guide implementation of the sustainability goal: • Continued public outreach to all interested parties and stakeholders with transparency in all planning, evaluations, and findings regarding groundwater management activities. • Adaptively manage the ECC monitoring networks, by expansion and/or modification, based on periodic evaluations to ensure a comprehensive understanding of basin hydrogeology and mechanisms that affect groundwater sustainability. • Prioritize environmental justice and groundwater dependent ecosystems as beneficial uses. • Protect the groundwater supply of potentially underrepresented communities such as disadvantaged communities (DACs). • View the use and protection of groundwater as an integral part of long-term water management strategies for the Subbasin. • Protect and maintain sufficient groundwater storage to provide operational flexibility for all water year types and with consideration of climate change. • Acknowledge that within the ECC Subbasin there are criteria and solutions that are regionally appropriate by each GSA jurisdiction. 4 As defined under SGMA, the GSP implementation period is 20 years. The planning and implementation horizon is a 50-year time period over which the GSAs determine that plans and measures will be implemented to ensure that the basin or subbasin is operated within its sustainable yield. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-5 • Continued cooperative water resources management by GSAs and other water agencies through updated MOUs or other agreements to ensure that all activities needed to maintain sustainability are identified, funded, and implemented. 7.2.2. Historical, Existing and Potential Future Conditions of Undesirable Results Groundwater conditions in the ECC Subbasin exhibit stability and sustainability. Historic and current use of the groundwater basin show no signs of chronic lowering of groundwater levels, reduction of groundwater storage, land subsidence, sea water intrusion, degraded water quality or depletion of interconnected surface water. Nonetheless, future potential undesirable results for each sustainability indicator were identified as required under GSP regulations. This was accomplished through a Sustainable Management Criteria survey, public meetings, and input from the GSP Working Group. Table 7-1 illustrates the historical, existing, and potential future conditions of undesirable results for the six sustainability indicators in the ECC Subbasin. Table 7-1. Summary of Undesirable Results Applicable to the Plan Area Sustainability Indicator Historical Period Existing Conditions Future Conditions with GSP Implementation Chronic Lowering of Groundwater Levels No No No Reduction of Groundwater Storage No No No Land Subsidence No No No Seawater Intrusion No No No Degraded Water Quality No No No Depletion of Interconnected Surface Water No No No 7.2.3. Measures to be Implemented Projects and management actions that have been completed or are planned to be implemented over the 20-year GSP implementation period (2022 through 2042) are discussed in (Section 8). These measures are developed to ensure that the ECC Subbasin will continue to be managed sustainably during GSP implementation and throughout the 50-year planning and implementation horizon. 7.2.4. Explanation of How the Sustainability Goal will be Achieved Undesirable results have not occurred historically and are not present in the ECC Subbasin. Furthermore, analyses of current monitoring data do not indicate undesirable results for the 20-year GSP implementation period. The GSAs will continue to work collaboratively and coordinate with other water supply entities, EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-6 implement various projects and management actions to strengthen overall water supply reliability in the region that would have direct and indirect positive effects on groundwater sustainability. The following projects and management actions, detailed in (Section 8), will be implemented to continue sustainability in the ECC Subbasin. 7.2.4.1. Projects 1. City of Antioch Brackish Water Desalination Project 2. Northeast Antioch Annexation Water and Sewer Facility Installation 3. City of Brentwood Non-Potable Storage Facility and Non-Potable Water Distribution 4. City of Brentwood Citywide Non-Potable Water Distribution System 5. Diablo Water District Treatment and Reuse of Alternative Water Supplies 6. ECCID-CCWD Dry-Year Water Sales 7.2.4.2. Management Actions The proposed management actions in this GSP will be implemented by individual GSAs based on need and applicability. The management actions are consistent with authorities granted to GSAs through SGMA legislation and GSP regulations. Implementation of any action will be in coordination and consistent with the Contra Costa County well permitting process and regulations. Consistent with SGMA, these potential actions do not apply to de minimis extractors5. 1. Well spacing control to mitigate potential impacts to existing wells 2. Oversight of well construction features such as completion intervals and seal depths to protect water quality and quantity using best management practices for the site conditions 3. Well metering, monitoring, and reporting to ensure accurate well and pumping data are provided to the GSAs 4. Pumping limits to protect existing supplies and avoid undesirable results 5. Pumping fees for implementing management actions The projects and management actions will ensure that the ECC Subbasin is managed sustainably through the regulatory planning and implementation horizons. 7.3. ECC Sustainability Indicators Each of the six sustainability indicators is defined by the following: undesirable results, minimum thresholds, and measurable objectives for the ECC Subbasin. The definitions of the sustainability indicators allow the GSAs, the State and the public to evaluate future conditions of the ECC Subbasin to ensure its managed sustainably and achieves the GSP sustainability goal. The categories of groundwater use in the ECC Subbasin are: 5 “De minimis extractor” means a person who extracts, for domestic purposes, two acre-feet or less per year. Section 10721, Water Code EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-7 • Agriculture • Commercial • Domestic Supply (Public Water Systems) o Small water system (2 to 199 connections) o Municipal supply (more than 200 connections) • Industrial (may include process water) • Environmental o Groundwater dependent ecosystems (see Basin Setting, Section 3, Figures 3-26a and b) o Other habitat protection including stream restoration projects 7.3.1. Chronic Lowering of Groundwater Levels 7.3.1.1. Undesirable Results Chronic lowering of groundwater levels is absent from the ECC Subbasin. However, the potential of chronic lowering of groundwater levels in ECC Subbasin is an undesirable result as defined in California Water Code Section 10721(x)(1): “Chronic lowering of groundwater levels indicating a significant and unreasonable depletion of supply if continued over the planning and implementation horizon. Overdraft during a period of drought is not sufficient to establish a chronic lowering of groundwater levels if extractions and groundwater recharge are managed as necessary to ensure that reductions in groundwater levels or storage during a period of drought are offset by increases in groundwater levels or storage during other periods.” 7.3.1.2. Criteria to Define Undesirable Results SGMA requires each GSP to consider the consequences of undesirable results even if they have not occurred historically or are projected to occur in the future. The ECC GSP defines significant and unreasonable chronic lowering of groundwater levels as: • Unreasonable reduction or loss of water well capacity that cannot be mitigated, applies to: o Agricultural wells o Commercial o Domestic supply wells  Municipal supply wells  Small water system wells  Private domestic wells o Industrial wells • Adverse economic impacts and burdens on local agricultural and commercial enterprises • Adverse economic impacts to existing well owners resulting in the need to: lower a well pump (“chasing the water”), to replace a pump, and/or to deepen or replace a well EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-8 • Loss of water source due to drop in water levels (wells going “dry”) • Cause sustained water level impacts to neighboring wells (well pumping interference) • Lack of prioritization of health and human safety over uses such as landscape irrigation • Interference with other sustainability indicators As indicated in the Water Code, water level declines in a drought, which may temporarily induce any of the above results, are not considered unsustainable if water levels recover in intervening non-drought periods. Implementing the ECC GSP projects and/or management actions will prevent the chronic lowering of groundwater. 7.3.1.3. Potential Causes of Undesirable Results There is no evidence that groundwater levels are chronically declining in the ECC Subbasin, and they are not expected to do so in the future. However, SGMA regulations require the GSP to identify future conditions (over 50 years) that may lead to chronically declining water levels, and they could include the following: • Significantly worse hydrologic conditions than currently projected under climate change scenarios (see Section 5). • Regulatory changes in streamflow requirements imposed by the SWRCB that reduce long standing surface-water rights and supplies. • Expansion of pumping in place of existing surface water supply source. Expansion of pumping may induce localized drawdowns and groundwater level declines. • Changes in the historical management of the Delta and salinity control point. The above hypothetical causes are considered unlikely under projected land and water uses and the cooperative regional water supply coordination among GSAs and other agencies. In addition, factors such as climate change and sea level rise are included in the ECC Subbasin groundwater budget as described in (Section 5). 7.3.1.4. Potential Effects of Undesirable Results A potential effect for the chronic lowering of Shallow Zone groundwater levels is the potential impact to domestic well owners whose wells may go dry and decrease shallow water available to groundwater dependent ecosystems. These changes could impact property values, quality of life, and environment in the ECC Subbasin. Changes in groundwater levels in the Deep Zone where pumping for large systems serving municipalities occurs could impact groundwater supply reliability and increase costs for consumers throughout the Subbasin. 7.3.1.5. Minimum Thresholds Section 354.28(c)(1) of the SGMA regulations states: “The minimum threshold for chronic lowering of groundwater levels shall be the groundwater elevation indicating a depletion of supply at a given location that may lead to undesirable results.” EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-9 Groundwater elevation data collected from existing and new groundwater monitoring wells, known as Representative Monitoring Site (RMSs), are used to measure the level of groundwater in the ECC Subbasin. Future groundwater level measurements will be evaluated against the defined minimum thresholds to ensure chronic lowering of groundwater levels does not occur. (Figure 6-2 in Section 6) shows the location of the RMSs in the ECC Subbasin and Table 7-2, below, lists the minimum thresholds at each RMS. Appendix 7a includes hydrographs of historical groundwater levels with minimum thresholds and measurable objectives for chronic lowering of groundwater levels. The minimum thresholds for the chronic lowering of groundwater levels are informed by the Subbasin water budget quantified in (Section 5) using a groundwater flow model. Modeling scenarios were designed to quantify sustainable groundwater yield by successively reducing surface water deliveries and increasing pumping to the point that one or more sustainability indicators were adversely affected. These scenarios indicated that sustainable yield in the ECC Subbasin is likely constrained by changes in subsurface outflow to other subbasins and stream depletion. At the same time, groundwater levels and storage were not adversely affected. This is attributed to the direct connections to recharge sources tied to the Delta. Based on the modeling results, minimum thresholds for chronic lowering of groundwater levels are quantified using the lowest historical water levels observed in a well plus 10 feet. If the MT in any well is exceeded over three consecutive years, indicating a trend, and do not recover in normal to wet years, undesirable results would be evaluated in terms of affects related to sustainable management activities. Since groundwater levels in the ECC Subbasin have been stable historically through the present and are projected to remain that way in the future, this is a conservative approach that will be adapted as additional groundwater level data and experience is accumulated. The modeling tool developed in (Section 5) provides additional support for the conservative nature of this approach. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-10 Table 7-2. Minimum Threshold, Measurable Objectives, and Interim Milestones for Chronic Lowering of Groundwater Levels Representative Monitoring Site (RMS) Well Owner/ GSA Well Depth (ft bgs) Perforation Depths (ft bgs) Minimum Threshold Measurable Objective and Interim Milestones Groundwater Elevation (feet from mean sea level) Shallow Zone Wells Antioch MW-15ǂ Antioch 15 5-15 -9 0.6 5 Binn BBID 45 45 (TD) -4 16 New Well CCWD BG-2 COB 37.5 22.5-37.5 32 44 DWD MW-30ǂ DWD 15 5-15 -9 1 Well #11 (4-61-A) ECCID 100 50-100 12 40 TODB MW-30 TODB 30 Deep Zone Wells Antioch MW-90ǂ Antioch 90 75-85 -11 -1 Brentwood MW-14 Int. COB 240 200-210, 220-230 -48 16 Bethel-Willow Rd DWD 260 230-260 -15 -3 Stonecreek MW-300 DWD 300 230-240, 280-290 -37 -1.7 4AMW-357 TODB 357 307-347 -107 -21 Notes: Blue indicates New Monitoring Well, sustainability indicators will be set at the depth measured when the wells are installed. ǂ Well installed August 2021, MT and MO presented are interim until more data is available. 7.3.1.6. Information and Criteria Relied Upon to Establish the Minimum Threshold Information used to establish the minimum threshold for the chronic lowering of groundwater levels includes: 1. Historical groundwater elevations from basin-wide monitoring wells in the ECC Subbasin. 2. Depths and locations of existing wells. 3. Current and historical groundwater elevation contour maps. 4. Modeling scenario for basin sustainable yield including climate change. 5. Other Information from GSAs and interested parties regarding significant and unreasonable conditions. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-11 The minimum thresholds for chronic lowering of groundwater levels at each RMS is set at an elevation, when evaluated collectively, that could produce undesirable results in the ECC Subbasin. They are the following: 1. The minimum threshold for each RMS is set at a level for which the sustainable yield is exceeded based on groundwater flow model scenario (see Section 5). 2. Where chronic level declines do not exceed the sustainable yield, but otherwise cause undesirable results as described in this GSP. 3. For domestic wells, a minimum threshold which indicates that the 10th percentile of this category experiences a drop below the top perforations within the section where the RMS is located. This is considered protective of the water supply sustainability because it considers the most sensitive conditions of well operations. Minimum thresholds were tentatively set for the four new monitoring well sites based on modeling results and professional judgement. Measurable objectives are also tentative and were set at the initial water levels measured in the wells. As additional data is available; these values may be revised. The ECC Subbasin has not experienced chronic water level declines in the past. The initial MTs in this GSP may be considered as preliminary values which may change based on monitoring and annual reporting of groundwater conditions. Groundwater levels after the droughts of 2007-09 and 2013-16 recovered without even temporary undesirable results. This was due to multiple factors including water conservation and the diversification of supply sources (i.e., available surface water). Information on domestic wells installed in the past 30 years and for which perforation intervals were listed was downloaded from DWR’s Well Completion Report Map Application (DWR, 2019) dataset. Figure 7-3 shows the number of wells (color coded) and the shallowest well perforations (numeric value in each square). There is a wide range of completion interval for this category of well with the shallowest perforations indicating that some wells pump, at least partially, from the Shallow Zone, while the deeper perforations target only the Deep Zone. Wells completed in the Shallow Zone are generally isolated from pumping in the Deep Zone, where most pumping occurs in the Subbasin, by confining zones that prevent propagation of impacts vertically. Wells that pump solely in the Shallow Zone will ultimately be protected through the MTs and MOs being developed through expansion of shallow monitoring throughout the Subbasin. The Deep Zone wells will be protected through the MTs and MOs assigned to the RMS in Table 7-2. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-12 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-13 7.3.1.7. The Relationship of Minimum Thresholds for Other Sustainability Indicators In accordance with the DWR Sustainable Management Criteria BMP (2017), the GSP must describe: 1. The relationship between each sustainability indicator’s minimum threshold (how or why the MTs are the same or different). 2. The relationship between MTs for other sustainability indicators (e.g., how the water level minimum threshold would not trigger an undesirable result for land subsidence). All sustainability indicators are intrinsically related and SGMA requires an assessment that a particular MT does not result in an undesirable result arising in another sustainability indicator. The minimum thresholds for chronic lowering of groundwater are established to avoid undesirable results for the remaining sustainability indicators, as described below. • Reduction in Groundwater Storage. The groundwater level minimum thresholds are set with consideration that temporary exceedances during drought do not reflect an undesirable result if water levels recover in non-drought periods. The measurable objectives, which represent the anticipated long-term average groundwater levels, are not expected to result in significant or unreasonable change in groundwater storage based on historical conditions in the Subbasin. • Subsidence. A significant and unreasonable condition for land subsidence is permanent (inelastic) subsidence that damages infrastructure as caused by compaction of clay-rich sediments in response to declining groundwater levels. No such subsidence has been recorded in the ECC Subbasin nor are geologic conditions susceptible to inelastic compaction present as represented in the hydrogeologic conceptual model of the Subbasin. Therefore, groundwater elevation minimum thresholds for subsidence in the ECC Subbasin are not initially being set. However, the GSP monitoring plan includes regular evaluation of groundwater levels, Plate Boundary Observation data, and potential infrastructure impacts within GSA jurisdictions will be conducted and reported. • Seawater Intrusion. The groundwater level minimum threshold for shallow groundwater levels, will be protective of baywater intrusion in the Shallow Zone by avoiding downward vertical flow gradient that might otherwise induce saline water to migrate to water supply aquifers. • Degraded Water Quality. A significant and unreasonable condition of degraded water quality is exceeding regulatory limits for constituents of concern in wells due to actions proposed in the GSP Water quality could be affected by chronic lowering of water levels through three processes. o Lowering groundwater levels could cause changes in groundwater flow gradients that result in commingling of poor-quality groundwater with supply sources. o Lowering groundwater levels could change groundwater gradients and cause poor quality groundwater from contaminant plumes to migrate to wells not previously impacted. o Potential projects consisting of surface water recharge through the vadose zone to the water table. Such projects have the potential to flush constituents of concern (e.g., TDS and nitrates) from the vadose zone to the water table. There may be a temporary increase in higher constituent concentrations prior to eventual dilution and reduction in these constituents. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-14 At present, no such recharge projects are planned. However, the monitoring program developed for this GSP will be evaluated periodically to adapt to the GSP projects. • Depletion of interconnected surface waters. It is recognized that shallow groundwater and surface water are interconnected in the delta region including portions of the ECC Subbasin. Changes in groundwater elevation could impact GDE areas as a result in decreased outflow of fresh groundwater due to chronic water level declines. 7.3.1.8. How the MT was Selected to Avoid Causing Undesirable Results in Adjacent Basins The groundwater level minimum thresholds for the chronic lowering of groundwater levels established for the ECC Subbasin are expected to be protective of adjacent subbasins as there are no apparent direct connections between Deep Zone aquifers used for water supply in those basins. Further, the Delta provides a hydrologic buffer between the Solano, Eastern San Joaquin, and Tracy Subbasins such that Shallow Zone influences are not expected to propagate. The Pittsburg Plain Subbasin borders the City of Antioch between which there is either a groundwater divide or barrier to cross flow. New monitoring wells being installed in Antioch will provide more data on the relationship between the two subbasins. The modeling tool will be used to assess subsurface movement in and out of the subbasins to assess future changes and potential adverse conditions at the shared boundaries of those subbasins. 7.3.1.9. How the MT may Affect the Interests of Beneficial Uses and Users of Groundwater Groundwater level minimum thresholds for the chronic lowering of groundwater levels may affect beneficial uses, users, and land uses in the Subbasin. RMS sites were selected to provide a basis for evaluating changes and impacts to the different uses and users of water wells throughout the Subbasin. Rural residential land uses and users. The chronic lowering of groundwater level MT protects most domestic users of groundwater by considering the depths to which wells are completed and protection of reasonable operating margins for available pumping drawdown. A comparison of a hypothetical MT water surface was developed by interpolating MT values between RMS wells to potential domestic well locations based on DWR WCR data where construction in known. The precise locations and construction of wells that are currently active in the Subbasin is not known and some older WCRs may be associated with wells that are no longer active. If this hypothetical condition occurred with all wells experiencing the MT, less than 5% of the domestic wells in the Subbasin have the potential to go dry; i.e., the well would experience less than 10 feet of saturated screen. This comparison is highly conservative given the inclusion of wells that are 50 years old and that newer wells are likely not completed solely in the Shallow Zone. The proposed well inventory program discussed in Section 6 will aid the GSAs in refining the MT to maximize protection for this kind of user. Agricultural land uses and users. Similar to rural residential uses and users, chronic lowering of groundwater level MTs are intended to protect agricultural users and their ability to meet existing and projected demands through typical well and pumping configurations (e.g., depths, perforation intervals, pumping lifts). Urban land uses and users. The chronic lowering of groundwater level MTs are set so that existing and projected water demands can be met through typical well and pumping configurations (e.g., depths, perforation intervals, pumping lifts). Environmental uses and users. Environmental uses include groundwater dependent ecosystems for which data gaps have been identified and new monitoring installations planned. Initially, a baseline shall EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-15 be established to provide a basis for identifying effects of chronic lowering of groundwater and setting protective MTs. 7.3.1.10. How the MT Relates to the Federal, State, or Local Standards There are no applicable federal, state, or local standards for MTs related to chronic lowering of groundwater levels in the plan setting. 7.3.1.11. How each MT will be Quantitatively Measured The groundwater level minimum thresholds for the chronic lowering of groundwater levels will be directly and quantitatively measured at each RMS. Groundwater level monitoring will be conducted in accordance with the monitoring plan and protocols outlined in (Section 6) and will meet the requirements of the technical and reporting standards included in the SGMA regulations. The current representative monitoring network includes seven Shallow Zone wells and five Deep Zone wells. 7.3.1.12. Measurable Objectives and Interim Milestones Measurable objectives (MO) for the chronic lowering of groundwater levels are quantitative goals that reflect the Subbasin’s desired groundwater conditions and goal to achieve sustainability within 20 years. It is set above the minimum threshold to allow a zone of operational flexibility that allows for drought, climate change, conjunctive use operations, and other groundwater management actions. The measurable objective for chronic lowering of groundwater levels is the average spring elevation of groundwater at the RMS and its vicinity. Years in which drought caused temporary decline in water levels were excluded as outliers due to other causes (e.g., questionable field measurement). An example of setting MOs is illustrated for the RMS at the Town of Discovery Bay (Figure 7-4) in which measurements in Deep Zone production wells are shown with data from the RMS, which has a shorter period of record. In this situation, the MO at the RMS is informed by historical data from nearby wells of which the RMS is intended to be representative. The MOs for the Shallow and Deep Zone existing wells determined in this manner are listed in (Table 7-2) and are denoted on hydrographs in Appendix 7a. Measurable objectives are preliminary for new Shallow and Deep Zone RMSs installed in summer 2021. MOs for these new Shallow and Deep Zone wells will be set at the water level measured at the time the well was drilled. However, as additional data is accumulated, the MOs may be adjusted. Interim milestones are defined in five-year increments at each RMS to track progress toward meeting the sustainability goal. With the ECC Subbasin currently meeting the sustainability goal, the measurable milestones coincide with the measurable objective for this indicator (Table 7-2). Every five years the interim milestones will be reevaluated in the GSP review to confirm that management of the Subbasin satisfies the GSP sustainability goal. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-16 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-17 7.3.2. Reduction in Groundwater Storage 7.3.2.1. Undesirable Results As described in this GSP, the current and historical groundwater use in the ECC is free from undesirable results for groundwater storage. Additionally, modeling indicates that undesirable results are not anticipated to occur during the planning and implementation horizon. Stable groundwater levels from 1993 to 2019 indicate that historical pumping in the Subbasin has not depleted useable storage 6. The sustainable yield of the Subbasin is the total volume of groundwater that can be withdrawn on an average annual basis without leading to a long-term reduction in useable groundwater storage or interfering with other sustainability indicators. Section 5, Water Budget quantifies sustainable yield of the Subbasin at 72,000 AF/year using the groundwater flow model developed for sustainable management. The modeling tool will be used, refined, and updated as needed, to quantify sustainable yield to avoid significant and unreasonable reductions in groundwater storage. An undesirable result occurs when available groundwater storage is depleted to the degree that current uses and users are unable to meet groundwater demand. 7.3.2.2. Criteria to Define Undesirable Results SGMA requires each GSP to consider the consequences of undesirable results even if they have not occurred historically or are projected to occur in the future. The undesirable result for the reduction in groundwater storage are the same as previously described for chronic lowering of groundwater levels, which act as a proxy for the groundwater storage sustainability indicator. In addition, significant and unreasonable changes in groundwater storage from implementing sustainable management policies, projects, or actions would occur if they caused any of the following: • Reduction in groundwater storage that restricts the quantity of supply to satisfy existing beneficial use or harms an existing category of groundwater user. • Any long-term reduction in available drawdown for pump operating margins that adversely affects available capacity or supply. • Degraded water quality as a result of changed groundwater flow conditions. • Interference with other sustainability indicators. 6 Useable storage is that volume of groundwater that may be extracted within the constraints of a balanced water budget. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-18 7.3.2.3. Potential Causes of Undesirable Results The ECC Subbasin has experienced no long-term reduction in groundwater storage due to pumpage or other imbalance in the water budget. Although unlikely, hypothetical conditions that may lead to a reduction in groundwater storage include the following: • Prolonged drought. An extensive drought greater than planned for may cause increased pumping of groundwater and a reduction of groundwater storage to a significant and unreasonable level. • Regulatory changes in streamflow requirements imposed by the SWRCB that reduce long standing surface-water rights and supplies. • Expansion of pumping and reduced surface water use. The above hypothetical causes are considered unlikely under projected land and water use estimates even when the effects of climate change and sea level rise are considered (see Section 5). 7.3.2.4. Potential Effects of Undesirable Results The reduction of groundwater storage in the Shallow Zone (e.g., lowering of shallow zone groundwater levels) could potentially impact domestic well owners whose wells may go dry, decrease shallow water available to GDEs, and induce baywater intrusion causing degraded groundwater quality. These changes could impact property values, quality of life, and environment in the ECC Subbasin. Changes in groundwater storage in the Deep Zone, which provides the main source of water supply in the Subbasin, could impact groundwater supply reliability, and increase costs for users and consumers. 7.3.2.5. Minimum Thresholds SGMA Regulations (§354.36(b)(1)) allow GSAs to use groundwater elevation as a proxy for any sustainability indicator provided there is sufficient correlation between groundwater levels and the other metric (Sustainable Management Criteria BMP, 2017). This GSP uses chronic lowering of groundwater levels as a proxy for reduction in groundwater storage. As cited previously, useable storage, or sustainable yield, is estimated at 72,000 AFY. The ECC GSP groundwater flow model was used to determine the maximum sustainable yield and set groundwater elevation minimum thresholds (MT). As a proxy, the MTs for groundwater levels are protective of groundwater storage and beneficial uses and users in the Subbasin. 7.3.2.6. Measurable Objectives and Interim Milestones The measurable objectives and interim milestones for the reduction in groundwater storage sustainability indicator are the same as for the chronic lowering of groundwater levels. 7.3.3. Seawater Intrusion There is no evidence of seawater intrusion in the ECC Subbasin at present or in the past. However, potential mechanisms for saline baywater intrusion may be triggered as a result of sea-level rise, unsustainable levels of pumping, or changes in Bay-Delta water quality and flow requirements by the state Water Board. In recognition of these potential mechanisms, the seawater intrusion sustainability indicator is incorporated into the ECC Subbasin GSP. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-19 7.3.3.1. Undesirable Results Significant and unreasonable changes related to seawater intrusion as a result of implementing sustainable management policies, projects or actions could occur if they induce any of the following: • Changes in baseline water quality that cause significant and unreasonable impacts on groundwater supply for beneficial users in the Subbasin. • Changes in baseline water quality at any location which indicate new pathways or mechanisms of degradation of any freshwater source that adversely impacts existing beneficial uses and users. • Changes in baseline water quality that adversely interfere with other sustainability indicators. A data gap for monitoring the interface between baywater and shallow groundwater was identified in Section 6 and will be filled by the installation of monitoring wells at multiple sites in the second half of 2021. 7.3.3.2. Criteria to Define Undesirable Results SGMA requires each GSP to consider the consequences of undesirable results even if they have not occurred historically or are projected to occur in the future. Undesirable results for seawater intrusion would occur if inland migration of saline baywater adversely reduces groundwater availability through degraded water quality. The potential degradation of water quality will be monitored by groundwater chloride concentrations as previously discussed in Section 3.3.4. The criterion for potential undesirable results for this indicator is as follows: An undesirable result may be present if a bayside monitoring well has a chloride concentration above 250 mg/L over three consecutive years and is causally related to groundwater sustainable management in the Subbasin. An increasing trend in chloride concentration may indicate that saline baywater is advancing inland and represents an undesirable result for the seawater intrusion Indicator. None of the wells listed in Table 7-4 have chloride concentrations that exceed 250 mg/L. A chloride isocontour shall be developed as more data is collected. 7.3.3.3. Potential Causes of Undesirable Results Conditions that may lead to an undesirable result for seawater intrusion include the following: • Sea level rise and saline baywater migrating into the Shallow Zone and vertically to the Deep Zone where the majority of pumping occurs. • In combination with the above, changes in water quality and flow requirements by the state Water Board under the Bay-Delta Plan7. Periodic evaluations using the ECC Subbasin groundwater flow model will also be used to assess the potential causes and onset of undesirable results for this indicator (see model description in Section 5). 7 https://www.waterboards.ca.gov/waterrights/water_issues/programs/bay_delta/ Accessed June 29, 2021 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-20 7.3.3.4. Potential Effects of Undesirable Results Baywater intrusion into the ECC Subbasin could cause the groundwater supply to become more saline and impact the use of groundwater for domestic, municipal, and agricultural purposes. Historically, there have been no limitations on the primary groundwater supply source (the Deep Aquifer Zone) due to elevated chloride concentration. The state’s upper maximum contaminant level chloride concentration is 500 mg/L 8. The potential effects of undesirable results for seawater intrusion are: o Reduced available supply requiring users to replace wells or seek alternative sources of supply. o Cause economic hardships on domestic wells users, many of which reside in DACs, to install water treatment or seek alternative sources. o Added costs to systems serving municipalities to install treatment systems or seek alternate sources. o Reduced groundwater quantity and quality for agricultural supply. o Adverse effects to groundwater dependent ecosystems due to changes in freshwater quantity (e.g., outflow) and/or quality. o Adverse effects on property values for landowners that rely on groundwater for domestic and agricultural supply. 7.3.3.5. Minimum Thresholds Section §354.28(c)(3) of the Code of Regulations states: “The minimum threshold for seawater intrusion shall be defined by a chloride concentration isocontour for each principal aquifer where seawater intrusion may lead to undesirable results.” GSP regulations require that the minimum threshold for seawater intrusion be determined from a chloride isocontour line. In order to construct the isocontour, chloride concentrations at multiple monitoring locations are required. At present, Shallow Zone well chloride concentration data along the San Joaquin River is sparse and a chloride isocontour cannot be constructed. With the installation and sampling of new monitoring wells in 2021, a chloride isocontour will be developed as a basis for long-term monitoring for the seawater intrusion indicator. Consistent with other indicators in the ECC Subbasin, the initial isocontour is expected to be used as a minimum threshold until a more definitive value is determined. The expanded dataset from filling the Shallow Zone data gaps will be presented in the initial annual report in April 2022. Based on the Subbasin HCM (see Section 3), the Shallow Zone would be impacted first if baywater salinity increases. Nevertheless, the Deep Zone RMSs will also be monitored for chloride and the interim seawater intrusion minimum threshold chloride concentration for any Shallow Zone or Deep Zone well is set at 250 mg/L which is the recommended level Secondary Maximum Contaminant Level (SMCL). This is based on the observation that the majority of wells in the Subbasin have chloride concentrations near this level and any significant increase may be indicative of a degradation mechanism such as seawater intrusion. As 8 California secondary maximum contaminant level-upper limit for aesthetics (taste and color). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-21 data from the new monitoring wells are collected, this interim approach will be modified and ultimately be replaced through isocontour maps for both aquifer zones. 7.3.3.6. Information and Criteria Relied Upon to Establish the Minimum Threshold GSP Regulations (CCR 2016) require the following information when setting the seawater intrusion minimum threshold at a chloride isocontour: • Section §354.28(c)(3)(A): Maps and cross-sections of the chloride concentration isocontour that define the minimum threshold and measurable objective for each principal aquifer. • Section §354.28(c)(3)(B): A description of how seawater intrusion minimum threshold considers the effects of current and projected sea levels. Due to the data gap in Shallow Zone wells and chloride concentration data, a chloride concentration map for Shallow Zone and Deep Zone wells developed in Section 3, Figure 3-16d in lieu of a chloride concentration isocontour. A chloride isocontour will be developed through the addition of the new monitoring wells to fill data gaps as discussed in Section 6 and will be included with the submittal of the first annual report in April 2022. The groundwater flow model will be used to evaluate the potential impact of sea level rise on this indicator by assessing flow gradients along the margins of the Subbasin and the Bay- Delta water bodies. In addition, a groundwater transport model project is proposed in Section 8 to further evaluate water quality degradation mechanisms in the ECC Subbasin. 7.3.3.7. The Relationship of Minimum Thresholds for Other Sustainability Indicators The minimum thresholds for seawater intrusion are established to avoid undesirable results for the remaining sustainability indicators, as described below. • Chronic lowering of groundwater levels, Reduction in Groundwater Storage, Subsidence, Depletion of interconnected surface waters. The minimum threshold for seawater intrusion is not associated with mechanisms or processes that would impact the minimum thresholds for these sustainability indicators. • Degraded Water Quality. The minimum threshold for seawater intrusion is the same as for degraded water quality (250 mg/L chloride concentration) and will not cause an exceedance of groundwater quality minimum thresholds. 7.3.3.8. How the MT was Selected to Avoid Causing Undesirable Results in Adjacent Basins Adoption of the seawater intrusion minimum threshold is expected to be protective of adjacent subbasins by monitoring mechanisms that may also arise in those regions. The hydrogeologic setting for the Shallow Zone in the ECC Subbasin is sufficiently separate from aquifers in the Solano, Eastern San Joaquin, and Tracy Subbasins such that if intrusion arises due to ECC sustainable management activities, it would not be expected to propagate to those areas. The Pittsburg Plain Subbasin borders the City of Antioch and is separated by either a groundwater divide or barrier to cross flow. New monitoring wells being installed in Antioch will provide more data on the relationship between the two subbasins. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-22 The groundwater flow model will be used to assess subsurface movement in and out of the ECC Subbasin and to assess future changes and potential adverse conditions at the shared boundaries with those subbasins. 7.3.3.9. How the MT may Affect the Interests of Beneficial Uses and Users of Groundwater The minimum threshold for seawater intrusion is not expected to affect beneficial uses, users, or land uses in the Subbasin as it preserves existing water quality and seeks to protect future degradation. 7.3.3.10. How the MT Relates to the Federal, State, or Local Standards There are no federal, state, or local standards for seawater intrusion that are applicable to the ECC Subbasin. However, the GSP accounts for the fact that there are state and federal standards for chloride concentration which is monitored as an indicator for seawater intrusion mechanisms. 7.3.3.11. How Each MT Will be Quantitatively Measured Chloride concentrations are quantitatively measured in groundwater samples collected from the ECC GSP seawater intrusion monitoring network. Figure 3-16d presents the average chloride concentration for post-2008 measurements in Shallow and Deep Zone wells. It shows that most concentrations are below 250 mg/L. The symbols are color coded by aquifer to denote the aquifer zone. Noting that seawater has a total dissolved mineral content of 35,000 mg/L and a chloride concentration on the order of 19,000 mg/L, the groundwater monitoring data for the ECC Subbasin indicate that there is no inland saline intrusion of sea water into groundwater at any location). The minimum threshold for the Subbasin is set at a chloride concentration of 250 mg/L because average native chloride concentrations in groundwater are typically less than this value (see Figure 3-16a). Any trend of increasing chloride concentration in the RMSs, or migration of a chloride isocontour inland (when the Shallow Zone data gap is filled), will be interpreted as a possible indication that saline baywater is moving inland. An assessment would then be made to determine 1) if bay water salinity has the potential at any location to elevate groundwater chloride concentrations, 2) whether a gradient for inland migration exists, and 3) whether any local groundwater management activity induced conditions to change. While any future intrusion process is expected to be slow (e.g., on the order of years), chloride concentration monitoring using 250 mg/L as a trigger for examining possible links to sustainable management in the Subbasin would be protective of groundwater resources. 7.3.3.12. Measurable Objectives and Interim Milestones Measurable objectives for seawater intrusion are the desired conditions for the ECC Subbasin and are based on maintaining the current native chloride concentration in the Subbasin. The measurable objectives for each RMS are the average chloride concentrations from 2013 to 2017. Table 7-4 presents the measurable objectives for each RMS. If an RMS does not have groundwater quality data during this period, the cells are left blank and will be populated when data is collected. If chloride concentrations trend upward above the measurable objective, but below the minimum threshold, verification measures regarding links to groundwater management as described in the preceding section will be triggered. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-23 Since the chloride concentration in the Subbasin is currently stable and above minimum thresholds for all RMSs, the interim milestones are set at the same values as the measurable objectives shown in Table 7-4. No changes in quality are expected as a result of implementing projects and management actions described in Section 8. 7.3.4. Degraded Water Quality 7.3.4.1. Undesirable Results Significant and unreasonable changes in groundwater quality as a result of implementing sustainable management policies, projects, or other actions could occur if they cause any of the following: • Increases in concentrations of key groundwater quality constituents above drinking water maximum contaminant limits (MCLs) that reduce groundwater availability for domestic, agricultural, municipal, or environmental beneficial uses. • Changes in water quality that cause economic burdens placed on users to treat or replace sources of groundwater supply including but not limited to increased treatment costs to mitigate elevated mineral content such as hardness. • Adverse impacts to agricultural crop production, yield, and/or quality. • Migration of contaminants to domestic or agricultural sources of supply, including but not limited to unregulated discharges of hazardous substances, and from oil and gas wells. • Movement or increases in currently unregulated chemical constituents that adversely impact beneficial uses and users (e.g., DACs and environmental users) of groundwater. Overall, groundwater quality is satisfactory for the various beneficial uses in the ECC Subbasin. Some parts of the Subbasin experience naturally elevated TDS and chloride that are near or exceed the recommended SMCL indicating a higher baseline for these constituents. Elevated nitrate concentrations occur in shallow wells near Brentwood with concentrations exceeding the MCL attributable to past agricultural practices. Arsenic is generally less than the MCL and boron concentrations are naturally elevated in most wells. Water hardness varies and in some cases adds financial burdens on users needing to use water softeners. For municipalities, TDS and hardness may lead to customer dissatisfaction and limit the ability to blend groundwater with treated surface water under conjunctive use 9. In order to meeting customer water hardness expectations municipalities may be required to install expensive water treatment systems. 7.3.4.2. Criteria to Define Undesirable Results SGMA requires each GSP to consider the consequences of undesirable results even if they have not occurred historically or are projected to occur in the future. Any RMS that exceeds any state drinking water standard during GSP implementation because of groundwater management activities, would constitute an undesirable result for the degradation of groundwater quality. 9 Conjunctive use is the coordinated and planned management of both surface and groundwater resources in order to maximize the efficient use of both resources. https://water.ca.gov/Water-Basics/Glossary Accessed August 2021. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-24 7.3.4.3. Potential Causes of Undesirable Results Overall, groundwater quality is satisfactory for the various beneficial uses in the ECC Subbasin. However, potential causes of degraded groundwater quality may include the following: • Changes in groundwater gradients- Changes to the location or rates of pumping could result in mobilization and vertical migration of certain constituents from the Shallow Zone to the Deep Zone including saline water and anthropogenic sources of contamination or natural constituents of concern. • Changes in groundwater pumping patterns- Changes in location and rates of pumping may alter and increase contributions from zones containing higher dissolved minerals including hardness. • Groundwater recharge projects–Use of recharge basins could cause localized groundwater mounding resulting in altered flow directions and potential movement of water quality constituents towards wells in concentrations that exceed water quality standards. Also, recharge of poor-quality water that exceeds the MCL or SMCL. 7.3.4.4. Potential Effects of Undesirable Results The potential effects of undesirable results for degradation of water quality are the same as described above for seawater intrusion. 7.3.4.5. Minimum Thresholds SGMA regulations guide the setting of the minimum threshold for degraded water quality as follows: • The minimum threshold shall be based on the number of supply wells, a volume of water, or a location of an isocontour that exceeds concentrations of constituents determined to be of concern for the basin. The minimum thresholds for degraded groundwater quality in the ECC Subbasin were selected to avoid undesirable results induced as a result of implementing sustainable management policies, projects or actions. The minimum threshold at a given RMS in the ECC Subbasin is: • The three-year running average exceedance of an MCL for a key monitoring constituent. 7.3.4.6. Information Used and Methodology The information used to establish the degraded groundwater quality minimum threshold includes: • Historical groundwater quality from basin-wide monitoring wells in the ECC Subbasin. • Depths and locations of existing wells. • Federal and state drinking water quality standards. • Information from interested parties of significant and unreasonable conditions. Federal and state drinking water quality standards will be used to define degraded groundwater quality minimum thresholds. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-25 7.3.4.7. Degraded Groundwater Quality Minimum Thresholds Minimum thresholds were set to represent conditions considered just above conditions that could cause undesirable results in the ECC Subbasin as discussed in (Section 3). Table 7-3 lists the constituents of concern, the reason for concern, and the drinking water standard/minimum threshold. Table 7-3. Constituents of Concern for Groundwater Quality Minimum Threshold Constituent of Concern Reason for Concern Minimum Threshold Total dissolved solids Naturally Elevated; may be associated with higher hardness 1,000 mg/L1 Chloride Baywater Intrusion/Naturally Elevated 500 mg/L1 Nitrate as nitrogen Agriculture and Septic Systems 10 mg/L2 Arsenic Naturally Elevated 10 ug/L2 Boron Naturally Elevated 5,000 ug/L3 Mercury Mercury Mine Upstream 2 ug/L2 1. California Secondary Maximum Contaminant Level (SMCL) 2. California Primary Maximum Contaminant Level (SMCL) 3. US EPA Health Advisory for non-cancer health effect. The TDS minimum threshold of 1,000 mg/L is generally protective for domestic and agricultural uses. TDS is secondary standard established for aesthetic purposes such as taste, odor, and color and not based on public health concerns. Note: public water system threshold of 500 mg/L for TDS. Groundwater contains numerous naturally occurring minerals that vary throughout the ECC Subbasin. While groundwater quality is generally favorable with respect to primary drinking water quality constituents, some areas have elevated total dissolved minerals, hardness, and some secondary constituents which may affect domestic and agricultural uses. The GSP is intended to avoid degradation of water quality as a result of implementing sustainable management policies, projects or actions. For example, projects that affect pumping patterns resulting in movement and mixing of groundwater sources that adversely affect certain users. The GSP does not mitigate groundwater quality in the Subbasin that is naturally occurring during the historical baseline.” 7.3.4.8. The Relationship of Minimum Thresholds between Like and Different Sustainability Indicators All sustainability indicators are intrinsically related and SGMA requires an assessment that a particular MT does not result in an undesirable result arising in another sustainability indicator. There is a minor influence on other sustainability indicators due to the potential degradation of groundwater quality. However, minimum thresholds were set to avoid undesirable results for other sustainability indicators as described below: EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-26 • Chronic lowering of groundwater levels and groundwater storage. Recharge projects implemented to mitigate lower water levels and storage must use sources that do not exceed any of the groundwater quality minimum thresholds. • Other sustainability indicators (seawater intrusion, subsidence, and depletion of interconnected surface water). The groundwater quality minimum threshold is not associated with mechanisms or processes that would impact other minimum thresholds. 7.3.4.9. How the MT was Selected to Avoid Causing Undesirable Results in Adjacent Basins The anticipated effect of the degraded groundwater quality minimum thresholds on each of the neighboring basins is the following: Tracy Subbasin (medium priority), Eastern San Joaquin Subbasin (critically-over drafted), Solano Subbasin (medium priority). Minimum thresholds are set to protect groundwater quality. Any interaction, such as outflow to another basin, would not induce undesirable results in those areas. The interpreted groundwater flow direction in the ECC Subbasin is generally to the Delta and outflow to the ocean further reducing the likelihood of causing impacts to the surrounding basins. Pittsburgh Plain Basin (low priority). There is no interpreted direct hydraulic connection with the Pittsburg Plain Basin. The City of Antioch borders the Pittsburg Plain Basin and does not pump groundwater, primarily due to poor native water quality. The ECC Subbasin degraded groundwater quality minimum threshold is protective of groundwater quality and would otherwise not induce undesirable results in that basin. 7.3.4.10. How the MT May Affect the Interests of Beneficial Uses and Users of Groundwater Degraded groundwater quality minimum thresholds are not expected to have negative effects on beneficial uses, users, or land uses in the Subbasin as described: • Rural residential land uses and users. The groundwater quality minimum thresholds protect domestic users of groundwater including individual well owners, small water systems, and DACs by applying drinking water standards. • Agricultural land uses and users. The groundwater quality minimum thresholds protect agricultural users by applying drinking water standards which exceed generally acceptable irrigation quality. • Urban land uses and users. The groundwater quality minimum thresholds protect municipal supplies by applying the same drinking water standards required under state permits. • Ecological land uses and users. The groundwater quality minimum thresholds protect groundwater dependent ecosystems by employing standards that maintain current or existing conditions and preventing future degradation. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-27 7.3.4.11. How the MT Relates to the Federal, State, or Local Standards The MTs for water quality degradation are based on federal, state, and local regulations for groundwater source protection and drinking water quality standards. 7.3.4.12. How Each MT Will be Quantitatively Measured The minimum threshold for degraded groundwater quality will be directly and quantitatively measured in accordance with the monitoring plan and protocols outlined in Section 6 and will meet the requirements of the technical and reporting standards under SGMA regulations. The current representative monitoring network includes five Shallow Zone wells and six Deep Zone wells that are either designated monitoring wells or public supply wells. 7.3.4.13. Measurable Objectives and Interim Milestones Measurable objectives for degraded groundwater quality are the desired conditions for the Subbasin and are based on maintaining the current water quality in the Subbasin. The measurable objectives for each RMS are the average concentrations (2013 to 2017) for each constituent of concern for each RMS (Figure 6-5). Table 7-4 presents the measurable objectives for each RMS. If a RMS does not have groundwater quality data during this period, the cells are left blank, and it will be calculated after five years of data collection. Since the groundwater quality in the Subbasin is currently sustainable and above minimum thresholds for all RMSs (Figure 6-5), the interim milestones are set at the same values as the measurable objectives shown in Table 7-4. No changes in quality are expected from projects and management actions implemented to achieve sustainability. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-28 Table 7-4. Minimum Thresholds, Measurable Objectives, and Interim Milestones for Degradation of Groundwater Quality Zone Well Name As (ug/L) B (ug/L) Cl (mg/L) Hg (ug/L) NO3 as N (mg/L) TDS (mg/L) Minimum Threshold 10 5,000 250 2 10 1,000 Shallow Zone BG-1 2.7 230 210 0.01 27 890 Antioch MW-15 DWD MW-15 TODB MW 15 Unknown Deep Zone Antioch MW-100 City of Brentwood Well 13 2.0 1,800 92 1.00 2.5 540 City of Brentwood Well 14 3.2 1,150 180 1.00 4.1 970 Glen Park Well 2.3 1,3001 100 1.00 1.2 690 Bethel-Willow Rd Town of Discovery Bay Well 4A 2.5 2,200 100 0.51 0.25 600 Notes: Blue shading indicates New Monitoring Well; Measurable objectives and interim milestones will be set at the concentrations from the initial results. Interim Milestones are the same as Measurable Objectives (e.g., the average concentrations [2013 to 2017]). 1Average Concertation between 2006-2007 7.3.5. Land Subsidence 7.3.5.1. Undesirable Results Land subsidence associated with groundwater pumping is a result of dewatering, or “mining” groundwater, from fine-grained geologic materials such as clay. The inelastic nature of this mechanism results in permanent deformation of the land surface and compaction of geologic formations. The potential undesirable results for this type of land subsidence are: • Impacts to infrastructure such as damage to roads and structures, reduced capacity of water conveyances, and increased vulnerability to flooding. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-29 There is no historic evidence of land subsidence related to groundwater pumping in the ECC Subbasin, in part or wholly due to the lack of formations which are susceptible to subsidence mechanisms 10. This sustainability indicator will be assessed using existing independent monitoring at a UNAVCO Plate Boundary Observatory (PBO) station (see Sections 3 and 6). In addition, groundwater level and interferometric synthetic aperture radar (InSAR) measurements will be used to support analysis of the PBO data as discussed below. 7.3.5.2. Criteria to Define Undesirable Results SGMA requires each GSP to consider the consequences of undesirable results even if they have not occurred historically or are projected to occur in the future. For this sustainability indicator, undesirable results occur when inelastic land subsidence due to groundwater extraction results in significant and unreasonable impacts to roads and structures, water conveyances, and flood control facilities. 7.3.5.3. Potential Causes of Undesirable Results A potential cause of undesirable results for the land subsidence sustainability indicator is the following: • Increased pumping in susceptible areas – Compressible clays of sufficient volume which are susceptible to dewatering and compaction due to groundwater pumping have not been identified under the present hydrogeologic conceptualization of the Subbasin. Expansion of pumping into new areas where geologic formations susceptible to compaction mechanisms are present, may result in subsidence that has not been observed historically in the Subbasin. 7.3.5.4. Potential Effects of Undesirable Results The undesirable result for land subsidence includes impacts to infrastructure. The potential effects of undesirable results for this indicator would be the following: • Damage to water conveyance facilities and flood control facilities. • Reduced capacity of surface water delivery systems that in turn leads to increased groundwater demand. • Adverse effects to property values. • Economic burdens to mitigate damage. 7.3.5.5. Minimum Thresholds Land subsidence induced by groundwater pumping has not been observed in the ECC Subbasin including through recent state-wide drought periods (2007-2009 and 2012-2016). Despite the lack of historical land subsidence, minimum thresholds and measurable objectives are established to guide sustainable management response should land subsidence occur. 10 While land subsidence associated with groundwater pumping has not occurred historically, another type of subsidence due to exposure of peat soils in reclaimed lands in the Delta has occurred to a significant degree. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-30 Section 354.28(c)(5) of the SGMA regulations state that “The minimum threshold for land subsidence shall be the rate and extent of subsidence that substantially interferes with surface land uses and may lead to undesirable results.” A minimum threshold is based on data from the UNAVCO P256 Plate Boundary Observatory station described in (Section 3) and presented in (Figure 3-22). Two other sources of information, groundwater elevations and InSAR measurements, will be used for verification of associations with groundwater pumping and management in the Subbasin. A minimum threshold of 1 inch land surface elevation outside the historical elastic range over a three-year period as exhibited by monitoring data at the UNAVCO site P256. Deviations from this minimum threshold over three or more consecutive years may indicate the onset of an inelastic component of subsidence. The historic elastic range is approximately 0.8 inches observed between 2005 to 2016 (see Figure 3-22). Exceedance of this minimum threshold would not necessarily result in undesirable results; however, since land subsidence associated with groundwater pumping may occur over many years even after pumping stresses are reduced, it is desired to identify mechanisms and implement sustainability measures to ensure that significant and unreasonable impacts do not arise over time. 7.3.5.6. Information and Criteria Relied Upon to Establish the Minimum Threshold Information used to establish minimum threshold for land subsidence includes: 1. Historical subsidence measurements from P256 UNAVCO station. 2. Current and historical groundwater elevation in wells. 3. Modeling scenario results of future groundwater level conditions 4. InSAR measurement surveys. The minimum threshold for subsidence is set to detect the onset of conditions that could potentially lead to undesirable results in the ECC Subbasin as follows. In addition to the PBO station monitoring data, groundwater elevation data and InSAR measurements11 will be reviewed to determine whether any inelastic component of land subsidence, should it occur, is related to groundwater pumping. This includes review of minimum thresholds for chronic groundwater decline. If the MT for land subsidence is exceeded for three consecutive years and an associated with groundwater pumping is verified, new adaptive management measurements will be developed and detailed in the subsequent plan update report. 11 InSAR surveys have only been recently conducted in the ECC Subbasin area. Figure 3-22 shows survey results for the period June 2015 to June 2019 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-31 7.3.5.7. The Relationship of Minimum Thresholds between Like and Different Sustainability Indicators All sustainability indicators are intrinsically related and SGMA requires an assessment that a particular MT does not result in an undesirable result arising in another sustainability indicator. In the ECC Subbasin, the conservative nature of the land subsidence minimum threshold would have little or no impact to the other minimum thresholds. • Chronic lowering of groundwater levels. The land subsidence minimum threshold will not result in significant and unreasonable lowering of groundwater elevations. However, declining groundwater elevations may have causal association with land subsidence. • Reduction in Groundwater Storage. The land subsidence minimum threshold will not result in significant and unreasonable change in useable groundwater storage. • Seawater Intrusion. The land subsidence minimum threshold will not cause an increase in baywater intrusion in the Subbasin. • Degraded Water Quality. The land subsidence minimum threshold will not result in significant and unreasonable changes in groundwater quality. • Depletion of interconnected surface waters. The land subsidence minimum threshold will not result in significant and unreasonable changes in groundwater elevations and will not impact depletion of interconnected surface waters. 7.3.5.8. How the MT was Selected to Avoid Causing Undesirable Results in Adjacent Basins There are four adjacent basins to the ECC Subbasin: • Pittsburg Plain Basin • Solano Subbasin • Eastern San Joaquin Subbasin • Tracy Subbasin The land subsidence minimum threshold induced by groundwater pumping was set to prevent significant and unreasonable land subsidence that damages infrastructure in the ECC Subbasin. No impacts to the adjacent basins are expected because 1) subsidence due to groundwater withdrawal has not occurred historically in the ECC Subbasin and 2) groundwater demand is projected to be stable or decrease in the future. In addition, the MT for land subsidence is sufficiently conservative to avoid adverse impacts from propagating outside the Subbasin. 7.3.5.9. How the MT May Affect the Interests of Beneficial Uses and Users of Groundwater The subsidence minimum thresholds are set to prevent inelastic subsidence that could impact infrastructure. Currently there is no inelastic subsidence occurring in the ECC Subbasin that impacts any beneficial user and the MT is sufficiently conservative to avoid impacts by subsidence and permit adaptive mitigation measures to be implemented if it occurs. 7.3.5.10. How the MT Relates to the Federal, State, or Local Standards There are no federal, state, or local standards for land subsidence. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-32 7.3.5.11. How Each MT Will be Quantitatively Measured Minimum thresholds are based on UNAVCO data for site P256 and measurements of groundwater levels as described in Section 6. 7.3.5.12. Measurable Objectives and Interim Milestones The measurable objectives and interim milestones are based on the elastic range of historically observed land deformation at the UNAVCO P256 station. The measurable objective and interim milestones for P256 is set at the average seasonal elastic movement (0.6 inch vertical) as shown in (Figure 3-22). Deviations from this measurable objective over three or more years may indicate the onset of an inelastic component of subsidence as discussed above. 7.3.6. Depletions of Interconnected Surface Waters As described in Section 3.3.8, the majority of the ECC Subbasin may have interconnected surface water and groundwater through the Shallow Zone. In the Subbasin setting, the major surface water conveyances are the San Joaquin River and Old River. These conveyances are influenced by two major water supply projects, the California State Water Project and the federal Central Valley Project. Through the Bay-Delta Plan, the state Water Board sets regulations for water quality and flow to protect both environmental and water supply concerns in the region. Thus, shallow groundwater and surface water interconnections are not controlled locally or by the ECC Subbasin GSAs. The hydraulic connections between groundwater and surface water have not been definitively characterized. New shallow monitoring wells are being installed as part of this GSP at locations on the San Joaquin River and Old River, and immediately upstream of the San Joaquin and Sacramento confluence in Antioch. This expanded Shallow Zone monitoring network, plus two existing shallow wells on western creeks, will be used to characterize the nature of surface water-groundwater connections and to assess the surface water depletion sustainability indicator in relation to local groundwater management as instituted in the ECC Subbasin GSP. Groundwater level monitoring adjacent to streams will be used with existing stream gages to show the spatial and temporal relationships between groundwater and surface water heads. The groundwater flow model described in Section 5 will be used as a comparative tool to provide initial estimates of the limits of groundwater pumping in the Subbasin which could cause undesirable results for stream depletion. This provides an interim basis for setting minimum thresholds and measurable objectives which can then be refined using data from the expanded Shallow Zone and surface water monitoring networks. 7.3.6.1. Undesirable Results There is no evidence of past or present significant and unreasonable depletions of surface water as a result of groundwater use in the ECC Subbasin. Major rivers and streams that have a hydraulic connection to the groundwater system are the San Joaquin River and Old River. Managed conveyances (i.e., conveyances for irrigation water, drainage, and flood control) are generally not considered in the analysis of depletions. Creeks, including Marsh Creek, are considered important aspects of the environmental EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-33 setting and the Shallow Zone monitoring network is designed to assess the presence of depletion mechanisms for these features (see Section 6). 7.3.6.2. Criteria to Define Undesirable Results SGMA requires each GSP to consider the consequences of undesirable results even if they have not occurred historically or are projected to occur in the future. Significant and unreasonable depletions of interconnected surface waters in the Subbasin are defined as: • Depletions that result in reductions in flow or stage of major rivers and streams that are hydrologically connected to groundwater in the Subbasin and which cause significant and unreasonable impacts on beneficial uses and users of surface water and the environment. The relationship between shallow groundwater levels and potential impacts on species and habit will be evaluated as data are collected from the expanded Shallow Zone monitoring network discussed in Section 6. 7.3.6.3. Potential Causes of Undesirable Results Potential causes of depletion of interconnected surface water include the following: • New large-scale pumping or diversions from shallow wells. • New localized pumping from Deep Zone wells in locations that are vertically connected to the Shallow Zone and surface water. • Interception or reduction of natural patterns of groundwater discharge to surface water. 7.3.6.4. Potential Effects of Undesirable Results Depletions of interconnected surface water could result in: • Reduction in flows that negatively impact aquatic species and groundwater dependent ecosystems. • Reduced flows within rivers and streams that adversely impact diversions for agricultural or urban users. • Increased costs to mitigate impacts. 7.3.6.5. Minimum Thresholds Section 354.28(c)(6) of the SGMA regulations states: “The minimum threshold or depletions of interconnected surface water shall be the rate or volume of surface water depletions caused by groundwater use that has adverse impacts on beneficial uses of the surface water and may lead to undesirable results.” The rate and volume of flow in and out of surface water have been initially quantified through water budget modeling scenarios in Section 5. For the Base Period 1997 to 2018, the average annual groundwater inflow attributed to all surface water features was 18,560 AFY and ranged from 10,135 to 31,887 AFY. High values occurred during dry years and the low values during wet years. For sustainable yield scenarios, groundwater pumping at higher than historical levels were simulated to assess potential impacts to the interconnected surface water indicator. The historical average annual EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-34 pumping in the ECC Subbasin during the Base Period was approximately 46,455 AFY. Annual pumping ranged between a high of approximately 58,250 and a low of 32,500 AF in dry and wet years, respectively. In the sustainable yield scenarios, surface water deliveries were reduced by 40, 45, 50, and 75 percent. This resulted in greater groundwater pumping to meet various demands. Relative to the Base Period average, these four scenarios resulted in 30, 42, 55, and 135 percent more groundwater pumping. With regard to sustainability indicators, the contribution to the water budget from surface water features (i.e., depletion) in the 75-percent surface water reduction scenario was nearly 10,000 AFY more than the Base Period average (approximately 26,850 versus 17,770 AFY). Net subsurface flow between adjoining groundwater basins also changed significantly for the highest surface water reduction scenario. Instead of average outflow of -8,500 AFY in the Base Period, this scenario resulted in about 8,300 AFY inflow. From the modeling, it was seen that up to 50 percent reductions in surface water deliveries, there were no significant changes in water budget components that might induce undesirable results. At the more conservative 75-percent reduction scenario, undesirable results may be triggered for the interconnected surface water sustainability indicator. While no conclusion was drawn as to whether this scenario actually would lead to significant and unreasonable results, the results indicate that changes in basin management that result in sustained pumping in all water years at more than twice the historical average (i.e., 135 percent) would be required to induce a major changes in surface water depletion. Based on the groundwater flow model results, a conservative interim minimum threshold for depletion of interconnected surface water is set at a value corresponding to 45 percent reduction in surface water deliveries. In this scenario, sustained basin-wide pumping would be 42 percent greater than the historic Base Period average, or 66,000 AFY. While this leads to a moderate increase in average contribution from surface water bodies in the subbasin water budget (about 18,100 AFY versus 17,800 AFY), it serves as conservative threshold at which closer examination of undesirable results could be undertaken if more groundwater use is projected in the future. Greater precision and accuracy for the minimum threshold for this sustainability indicator may be achieved by using Shallow Zone groundwater levels as a proxy. This proxy would be complemented by the stream stage monitoring network described in Section 6. GSP regulations allow GSAs to use groundwater levels as a proxy metric for any sustainability indicator if the GSP demonstrates there is significant correlation between groundwater levels and the depletions of interconnected surface water. The relationship between the ECC Subbasin GSP groundwater flow model results and measured groundwater level data will serve as a basis for determining the effectiveness of a groundwater level proxy. Since no apparent surface water depletions are evident in the Subbasin, future projects and management actions shall be evaluated through comparative modeling scenarios and with monitoring data to assess potential mechanisms for the onset of undesirable rates of surface water depletion. 7.3.6.6. Information and Criteria Relied Upon to Establish the Minimum Threshold Water budget modeling scenarios presented in Section 5 are used to inform potential hydraulic mechanisms that could indicate significant and unreasonable results for this indicator. As data are developed, groundwater level minimum thresholds may be used as a proxy with data from the expanded Shallow Zone groundwater monitoring network and informed by the ECC groundwater flow model. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-35 7.3.6.7. How the MT May Affect the Interests of Beneficial Uses and Users of Groundwater The interconnected surface water minimum thresholds are set to avoid effects on beneficial users and land uses in the Subbasin: • Domestic and agricultural well owners: Currently there are no reported shallow groundwater level declines in the Subbasin and none are expected by employing a minimum threshold for this indicator. • Urban land uses and users: No changes are expected since no changes to shallow groundwater are expected. • Environmental land uses and users. The minimum threshold is set to protect GDEs near streams where there is a connection to shallow groundwater. 7.3.6.8. The Relationship of Minimum Thresholds for Other Sustainability Indicators The minimum thresholds for the depletions of interconnected surface waters are established to avoid undesirable results for other sustainability indicators, as described below. • Chronic Lowering of Groundwater Levels and Reduction in Groundwater Storage. Modeling scenarios indicate that the minimum threshold for interconnected surface water depletions would not trigger chronic declines in water levels or storage. • Land Subsidence. Since the minimum threshold for interconnected surface water depletions would not trigger chronic declines in water levels, land subsidence would not be induced. • Seawater Intrusion and Degraded Water Quality. The minimum threshold for the depletions of interconnected surface waters may be linked to these indicators as they may be affected by induced movement of surface water into the groundwater system at higher pumping volumes. However, the MT is sufficiently conservative that if pumping increased to the threshold, significant impacts are not expected to occur. Rather, the MT is set as a trigger to further assess the presence of mechanisms that might lead to undesirable results. 7.3.6.9. How the MT was Selected to Avoid Causing Undesirable Results in Adjacent Basins Adjacent basins are linked through their proximity and possible similar connections to the Bay-Delta ecosystem. The minimum threshold for the interconnected surface water sustainability indicator is conservatively based on comparative model scenarios that consider the entire Subbasin water budget including flows to and from other basins. The modeling results indicate that for a scenario of 135 percent increased pumping compared to the Base Period, significant changes in inter-basin flow to balance the ECC water budget could occur. It was concluded that setting an interim MT at 42 percent more pumping relative to the Base Period average, the potential impacts would be less than significant and allow the GSAs to conduct further modeling and monitoring to determine how and where impacts might occur if the pumping rates were projected to continue rising beyond that level. Using the ECC groundwater flow model to continually update the water budget will enable the ECC GSAs to identify needs for management changes to avoid adverse impacts to adjoining basins. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-36 7.3.6.10. How the MT Relates to the Federal, State, or Local Standards There are no federal, state, or local standards for depletion of interconnected surface water. However, depletion of interconnected surface water has the potential to conflict with the state Water Board Bay-Delta Plan and, as such, the GSAs will consider any future updates to the plan and how such updates may affect sustainable groundwater management in the ECC Subbasin, particularly with respect to the Shallow Zone. 7.3.6.11. How Each MT Will be Quantitatively Measured Groundwater flow modeling suggests a link to increased pumping and stream depletion over baseline levels. The flow model relies on quantitative groundwater level data as measured in the basin-wide and representative monitoring networks. The use of the model to assess this sustainability indicator may be complemented or replaced by proxy groundwater level measurements. 7.3.6.12. Measurable Objectives The measurable objectives and interim milestones for depletions of interconnected surface water sustainability indicator are set at the average annual groundwater pumping during the Base Period 1997 to 2018, or 46,455 AFY. In dry years, pumping increased to 58,250 AFY in the Base Period, still well below the 42-percent pumping increase used to define the MT. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 7 - SUSTAINABLE MANAGEMENT CRITERIA LSCE 7-37 7.4. References California Department of Water Resources (DWR). November 2017. Draft Guidance Document for the Sustainable Management of Groundwater: Sustainable Management of Groundwater, Best Management Practice. California Department of Water Resources (DWR). Well Completion Report Map Application. 2019. https://www.arcgis.com/apps/webappviewer/index.html?id=181078580a214c0986e2da28f8623b37. Accessed May 2019. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-i SECTION 8 CONTENTS 8. Projects and Management Actions (§ 354.44) ........................................................................... 8-1 8.1 Projects ...................................................................................................................................... 8-4 Project Implementation .................................................................................................... 8-5 List of Projects ................................................................................................................... 8-5 Completed Projects ........................................................................................................... 8-8 Project 1: Northeast Antioch Annexation Water and Sewer Facility Installation .......... 8-8 Project 2: Non-Potable Storage Facility and Pump Station ........................................... 8-9 Project 3: Dry-year Water Transfer ECCID/CCWD ....................................................... 8-11 Projects Under Construction ........................................................................................... 8-13 Project 4: Citywide Non-Potable Water Distribution System ...................................... 8-13 Project 5: City of Antioch Brackish Water Desalination Project .................................. 8-15 Planned Projects .............................................................................................................. 8-17 Project 6: Treatment and Reuse of Alternative Water Supplies .................................. 8-18 Project 7: Transport Model Development ................................................................... 8-19 8.2 Management Actions ............................................................................................................... 8-21 Potential Management Actions ....................................................................................... 8-21 Non-Applicability to De Minimis Users ........................................................................ 8-22 Coordination with Contra Costa County ...................................................................... 8-23 Management Action 1: Well Spacing Control .............................................................. 8-23 Management Action 2: Oversight of Well Construction Features ............................... 8-25 Management Action 3: Well Metering, Monitoring, and Reporting ........................... 8-26 Management Action 4: Demand Management Program ............................................ 8-27 Management Action 5: State Programs for Domestic Well Users ............................... 8-30 Other Water Conservation Actions ................................................................................. 8-31 8.3 References ............................................................................................................................... 8-33 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-ii LIST OF TABLES Table 8-1 Summary of ECC GSP Projects & Management Actions..………………………………………………8-3 Table 8-2 Summary of ECC GSP Projects……………………………………...…………………………………………..…8-7 Table 8-3 City of Antioch Brackish Water Desalination Project Funding Sources…………….……….…8-17 Table 8-4 Summary of Potential Management Actions………………..…………………………………………….8-22 Table 8-5 Summary of Water Conservation Programs………………...………………………………………….…8-32 LIST OF FIGURES Figure 8-1 ECC GSP Project Locations……………………………………………………………………………………………8-6 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-1 8. PROJECTS AND MANAGEMENT ACTIONS (§ 354.44) As established in Section 7, groundwater conditions in the ECC Subbasin exhibit stability and sustainability. The technical analysis of groundwater conditions shows through historic and current use of the Subbasin no signs of chronic lowering of groundwater levels, reduction of groundwater storage, land subsidence, sea water intrusion, degraded water quality or depletion of interconnected surface water. The Subbasin Sustainability Goal broadly includes maintaining safe and reliable access to groundwater, assessing and managing groundwater in the future under climate change, protecting the sustainable yield, and continuing to avoid undesirable results of groundwater extraction as defined by Subbasin stakeholders. Projects and management actions (PMAs) were developed to achieve the ECC Subbasin sustainability goal by 2042 and avoid undesirable results over the GSP planning and implementation horizon. Given the current and projected stability and sustainability of groundwater in the ECC Subbasin, PMAs are developed with the goal of maintaining sustainable groundwater conditions. PMAs include a suite of targeted PMAs that the GSAs may develop and implement, if needed under future conditions. The GSP also includes some PMAs that are expected to be implemented (or are already being implemented) by individual GSAs in the Subbasin to maintain sustainability. ECC Subbasin GSAs have identified a range of PMAs. Projects generally refer to structural programs, including, for example, direct and in-lieu recharge utilization of recycled water, and other capital improvement projects. In contrast, management actions are typically non-structural programs or policies that do not require a substantial capital outlay and are intended to incentivize reductions in groundwater pumping when needed. ECC Subbasin PMAs are described in accordance with 23 California Code of Regulations (CCR) §354.44. Because the ECC Subbasin is currently and projected to be sustainable over the implementation and planning horizon (i.e., no onset of undesirable results), PMAs are not expected to be essential for sustainability. However, future conditions are uncertain and PMAs are viewed as enhancing management capabilities and will be implemented on an as-needed basis. It is anticipated that PMAs would be targeted at specific regions that may emerge in the future as potential areas of concern. Projects included in the GSP include infrastructure to provide in-lieu recharge, improve water quality, and increase use of recycled wastewater. Projects are either ongoing, under construction, or in the planning stage and are expected to help maintain sustainable conditions in the Subbasin and mitigate potential future problems. The estimated groundwater recharge benefit and capital cost of each project is shown. Project cost information is limited for many projects because a detailed feasibility assessment has not been completed. Other projects have cost estimates that were developed several years ago and may not reflect current conditions. To the extent possible, project costs are adjusted and reported on a consistent basis. GSAs and other agencies in the Subbasin will further develop projects during the GSP implementation period and refine estimated costs. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-2 Management actions are options available to the GSAs if groundwater conditions begin to trend below Measurable Objectives (MO) or approach Minimum Thresholds (MT). Some GSAs may implement management actions proactively as a local policy. However, this appears unlikely based on current and projected groundwater modeling for the Subbasin (Section 7). Management actions in the GSP include oversight of well construction features, metering, and demand management. Management actions have more concise descriptions because they generally do not require outside approval or infrastructure and are part of authorities granted to GSAs under SGMA legislation. Benefits and costs will mostly depend on necessity and the extent of the area or areas which would require the action. In accordance with CCR §354.44(b)(9), GSAs will identify sources of funding to cover project development, capital, and operating costs, including but not limited to, groundwater extraction fees, increasing water rates, grants, low interest loans, and other assessments. The exact funding mechanism will vary by project and the legal authority of each GSA (or project proponent). A general description of how each GSA expects to cover costs is presented after the description of each project. Individual GSAs or other water agencies in the Subbasin will manage the permitting and other specific implementation oversight for its own projects. The ECC GSAs have an obligation to ensure groundwater sustainability in the Subbasin, however, they are not the primary regulator of land use, water quality, or environmental project compliance. The individual GSAs will be responsible for implementing projects and management actions in accordance with applicable statutes and regulations, and in coordination with other local, state, and federal authorities that may have permitting and regulatory authority over PMAs. GSAs will notify the public and other agencies of the planned or ongoing implementation of PMAs through the communication channels identified for each project (23 CCR §354.44(b)(1)(B)). Noticing will occur as projects are being considered for implementation, and as future projects are implemented. Noticing will inform the public and other agencies that the GSA is considering or has implemented the PMA and will provide a description of the actions that will be taken. PMAs are categorized and presented in this chapter according to the current status of implementation and development. This is consistent with the adaptive approach to PMA implementation and with development of PMAs based on the best available data and science (per 23 CCR §354.44(c)). This chapter also acknowledges ongoing investments made by GSAs and other agencies in the Subbasin (including prior to the passage of SGMA), such as projects that were identified and moved forward under regional water management planning efforts. The PMA categories described in this chapter include: • Completed Projects and Management Actions are PMAs that the GSA or other project proponents have implemented that will support sustainable groundwater management in the Subbasin. In accordance with 23 CCR §354.44(a) these are PMAs that would allow GSAs to achieve the sustainability goal for the ECC Subbasin and avoid minimum thresholds defined in this GSP under future, changing conditions. • Under Construction Projects and Management Actions are PMAs that are being implemented and will support sustainable groundwater management in the Subbasin. In accordance with 23 CCR EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-3 §354.44(a) these are PMAs that would allow GSAs to achieve the sustainability goal for the Subbasin and avoid minimum thresholds defined in this GSP under future, changing conditions. • Planned Projects and Management Actions are PMAs that are expected to be implemented and support sustainable groundwater management in the Subbasin. These may have been studied by the project proponent, or in earlier regional water planning documents, but most project design, costs, and planning work has yet to be completed. • Conceptual Projects and Management Actions are PMAs that are being discussed as potential options to be implanted only as needed in any areas of the Subbasin facing deleterious groundwater conditions. This is not expected in the Subbasin as a whole, but these PMAs may be considered in specific areas facing unforeseen unsustainable conditions due to, for example, prolonged drought or supply disruption. Table 8-1 summarizes the PMAs, type, and expected benefits to measurable objectives in the Subbasin. Most proposed PMAs are expected to benefit groundwater levels and groundwater storage, whether through direct or in-lieu groundwater recharge, management of water supplies, or demand reduction. Projects that increase the overall water supply are also expected to reduce depletions of interconnected surface water. Some management actions would potentially benefit all measurable objectives if those were ultimately triggered for implementation. Table 8-1. Summary of ECC Projects & Management Action Project/ Management Action Name Project/ Management Action Category Measurable Objectives Expected to Directly Benefit GW Levels GW Storage SW Depletion Land Subsidence Seawater Intrusion Water Quality Northeast Antioch Annexation Water and Sewer Facility Installation Completed X X X Non-Potable Storage Facility and Pump Station Completed X X X Dry-Year Water Transfer ECCID/CCWD Completed X X X Citywide Non- Potable Water Distribution System Under Construction X X X City of Antioch Brackish Water Desalination Project Under Construction X X X X EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-4 Project/ Management Action Name Project/ Management Action Category Measurable Objectives Expected to Directly Benefit GW Levels GW Storage SW Depletion Land Subsidence Seawater Intrusion Water Quality Treatment and Reuse of Alternative Water Supplies Planned X X X X Transport Model Development Planned X Well Spacing Control Conceptual X X X Oversight of Well Construction Features Conceptual X Well Metering, Monitoring, and Reporting Conceptual X X X X Demand Management Program Conceptual X X X X X X Water Conservation Programs Varied X X X X X X This rest of this chapter is structured as follows. Section 8.1 provides a summary of projects. The three subsequent subsections describe the projects in each of the three categories. Section 8.2 describes management actions. 8.1 Projects Seven (7) projects are included in the GSP. These projects provide a benefit to water supply or water quality, and are currently completed, under construction, or planned for implementation over the next 20 years (GSP implementation period). As described above and in Section 7, groundwater conditions are projected to be sustainable over the GSP implementation period, even in the absence of any projects. The GSAs will continue to monitor groundwater conditions, and report on them in annual GSP reports and 5-year GSP updates. Some projects may be triggered if undesirable results are projected to occur and subsequent GSP updates would provide an implementation schedule and additional project details. The ECC GSP Working Group used the Integrated Regional Water Management (IRWM) Plan (ECWMA 2019) to generate a preliminary list of projects that have been previously developed and evaluated by local entities in the ECC Subbasin. The GSAs then selected projects from this list that are expected support sustainable groundwater management and help maintain sustainable conditions in the Subbasin. Some projects described in this section are extensions of those detailed in the most recent IRWM Plan. Interested parties EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-5 were informed and could provide feedback on the projects at a public workshop held on June 23, 2021; additional comments will be received during public review of this GSP. Project Implementation Projects will be administered by the project proponent (e.g., GSA). The project proponent has sole discretion to designate and implement a project in a timeframe in accordance with its funding, capability, and prioritization. No projects identified to date are considered essential for achieving the Subbasin sustainability goal because the ECC Subbasin is currently and projected to be sustainable over the implementation and planning horizon. List of Projects Seven possible projects to increase water supply availability and reliability in the ECC Subbasin were identified and are included in the GSP. These projects help contribute to the current and continued sustainability of the Subbasin. Projects include water recycling and water quality and are detailed in the project summaries below and in Figure 8-1 and Table 8-1. Figure 8-1 illustrates projects that are completed or under construction. Table 8-2 lists projects which are completed, under construction, or planned. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-6 Figre 8-1 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-7 Table 8-2. Summary of ECC GSP Projects Name Type Proponent MO to Benefit Status Completion Year1 Capital Cost ($) Expected Yield2 Northeast Antioch Annexation Water and Sewer Facility Installation In-Lieu Recharge / Water Quality City of Antioch Groundwater Levels, Groundwater Storage, Water Quality Completed 2020 4,400,000 8 AFY (.0007 MGD) Non-Potable Storage Facility and Pump Station In-Lieu Recharge / Recycled Water City of Brentwood Groundwater Levels, Groundwater Storage, Interconnected Surface Water Completed 2020 12,804,500 1,661 AFY (1.5 MGD) Dry-Year Water Transfer ECCID/CCWD In-Lieu Recharge East Contra Costs ID Groundwater Levels, Groundwater Storage, Interconnected Surface Water Completed 2000 N/A 4,000 AFY (3.5 MGD) Citywide Non-Potable Water Distribution System In-Lieu Recharge / Recycled Water City of Brentwood Groundwater Levels, Groundwater Storage, Interconnected Surface Water Under construction 2021 9,054,036 1,661 AFY (1.5 MGD) City of Antioch Brackish Water Desalination Project In-Lieu Recharge City of Antioch Groundwater Levels, Groundwater Storage, Interconnected Surface Water Under construction 2023 110,000,000 6,720 AFY (6 MGD) Treatment and Reuse of Alternative Water Supplies In-Lieu Recharge / Recycled Water Diablo Water District Groundwater Levels, Groundwater Storage, Interconnected Surface Water Planned TBD 20,000,000 to 100,000,000 2,800 AFY (2.5 MGD) Transport Model Development3 Water Quality Diablo Water District Water Quality Planned TBD 250,000 to 500,000 N/A 1. SGMA’s required planning implementation horizon is 50 years. 2. Represents total offset to water supply; direct benefits to groundwater will vary. 3. The Transport Model Development project is in progress. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-8 Completed Projects Projects in this category are completed and operating. They have either been completed recently and will have benefits not accounted for in the water budget described in Section 5, or they are ongoing with the capacity to expand. These projects provide in-lieu groundwater recharge benefits. The estimated cumulative benefit of these projects is 5,669 AFY. Project 1: Northeast Antioch Annexation Water and Sewer Facility Installation Project Summary Submitting GSA City of Antioch Project Type In-Lieu Recharge / Water Quality Estimated Groundwater Offset and/or Recharge 8 AFY, Water Quality Benefits This project involved construction of new water and sewer facilities where there were none. Residents in this area had been relying on aging individual wells and septic tanks without access to municipal treated water or sewer services. This project provides facilities to a lower-income community, thus more equitably providing water access and protecting groundwater from potential septic tank and leach field contamination. Measurable Objective Expected to Benefit: This project, through reducing well use, helps avoid potential lowering of groundwater levels and reduction in groundwater storage. It also avoids potential water quality degradation from existing septic tanks and leach fields. Project Status and Timetable for Initiation and Completion: This project was completed in May of 2020. Required Permitting and Regulatory Process: All work was performed in City right-of-way or in areas that easements have been acquired. Permitting was required through BNSF Railroad for installation of a pipeline across its right-of-way. Expected Benefits and Evaluation: Groundwater recharge is an important part of the GSP and will be critical to maintaining long-term Subbasin sustainability. This project is anticipated to reduce 8 AFY in groundwater pumping by providing residents and businesses access to the City of Antioch water supply. Furthermore, the project is expected to benefit water quality through reduction of potential contamination. Benefits to groundwater levels and water quality will be evaluated through monitoring, as described in Section 6. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-9 How Project Will Be Accomplished/Evaluation of Water Source: New pipelines provide City water to residents that were not in the system. The source of water will be the City of Antioch, which is expected to provide a reliable water supply for the annexed area. Legal Authority: GSAs, in this case the City of Antioch GSA, have the authority to plan and implement projects. The City of Antioch is a local agency established to serve water for agricultural and municipal demands. Estimated Costs and Plans to Meet Costs: The capital cost for this project is $4,400,000. Costs for this project have been met through City of Antioch and County funds. Annual operating costs of the project are $21,500. Operating costs from the project are paid for by ratepayers. Circumstances for Implementation: A construction agreement for this work was approved by the Antioch City Council on December 11, 2018. The Notice of Completion was approved by the Antioch City Council on June 9, 2020. No further process is needed to determine the conditions which would require this project because it is already constructed. Notice to Public and Other Agencies Public noticing for this project is being done in accordance with noticing requirements and in public meetings held the City of Antioch GSA and others. Project 2: Non-Potable Storage Facility and Pump Station Project Summary Submitting GSA City of Brentwood Project Type In-Lieu Recharge / Recycled Water Estimated Groundwater Offset and/or Recharge Up to 1,661 AFY The Wastewater Treatment Plant (WWTP) discharges about 2 million gallons of recycled water per day into Marsh Creek. Utilization and blending of this valuable resource are major strategic components for compliance with the requirements of the National Pollution Discharge Elimination System (NPDES) Permit. This reduces the reliance and associated treatment costs on potable water and complies with both State and City mandates on increasing recycled water usage. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-10 The City of Brentwood is implementing steps to utilize more recycled water citywide; however, the peak daily recycled water supply (morning and evenings) does not align with the peak recycled water demand (night). The City of Brentwood needs an adequate storage facility to maximize utilization of this valuable resource. This project offsets the use of 1,661 AFY of potable water sourced in part from the Subbasin, reduces discharge to Marsh Creek, and reduces surface water diversions used for irrigation. Measurable Objective Expected to Benefit: This project, through increasing the city water supply, helps avoid potential lowering of groundwater levels, reduction in groundwater storage, and depletion of interconnected surface water. Project Status and Timetable for Initiation and Completion: This project was completed in 2020. Required Permitting and Regulatory Process: Requirements from the Central Valley Regional Water Quality Control Board, as part of the WWTP NPDES Permit, include that the City of Brentwood must expand recycled water usage and decrease discharge of treated water into Marsh Creek. Storage facility construction was completed following all required permitting and regulatory requirements. Expected Benefits and Evaluation: Recycled water is an important part of the City’s water resources. Recycled water allows the City of Brentwood to conserve potable water, thereby ensuring a reliable water supply for current and future demand. This project is expected to offset 1,661 AFY in water demand. The amount of in-lieu recharge depends on the availability of other sources, but some offset of groundwater pumping is expected. The Non-Potable Storage Facility project will improve access to recycled water supplies. Alternate water supplies will be an important component of the priorities and requirements to facilitate sustainable groundwater management and will be critical to establishing long- term groundwater sustainability. Benefits will be evaluated through volumetric measurement of recycled water added back into the system. How Project Will Be Accomplished/Evaluation of Water Source: The City’s Wastewater Treatment Plant’s tertiary treatment and disinfection provides recycled water for landscaping. The City of Brentwood is a producer and distributor of Title 22 tertiary recycled water for unrestricted reuse. Upon completion of the pipeline installation, recycled water will be pumped throughout the City of Brentwood for irrigation uses in lieu of potable water. Since the source of water is recycled wastewater, this is expected to be reliable even during drought periods. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-11 Legal Authority: GSAs, in this case the City of Brentwood GSA, have the authority to plan and implement projects. Unrestricted, non-potable recycled water is defined as wastewater that has been treated to tertiary standards (via filtration and disinfection) that meet Title 22 of the California Code of Regulations (California Department of Public Health, 2018). The production and distribution of recycled water is covered in the City’s Master Reclamation Permit. Recycled water treated to this level can be used for all outdoor irrigation demands in a community, including parks, schools, street medians, residential front and backyard landscaping, public open space, as well as industrial uses such as cooling water. Estimated Costs and Plans to Meet Costs: The capital cost for this project was $12,804,500. The project was funded by a State Water Resources Control Board Revolving Fund “SRF” loan, so project approvals were obtained from the Regional Water Quality Control Board (RWQCB) and other affected local agencies. The SRF funding consisted of 35% from State and Federal grants and 65% from a loan that will be repaid using Wastewater Development Impact Fees and Wastewater Enterprise Funds. Annual operating costs associated with this specific project are minor because this is an improvement on existing WWTP operations, which are already paid for by ratepayers. Circumstances for Implementation: This project was completed in 2020. The City of Brentwood has developed preliminary planning documents to identify uses for recycled wastewater at both existing and future sites. The recycled wastewater will be used for the irrigation of parks and other landscape amenities. The City of Brentwood already has constructed a portion of the recycled water distribution system and will continue to expand the system as the City of Brentwood grows. Recycled water demands are estimated to be 2,111 AF (688 MGY) at buildout. No further process is needed to determine the conditions which would require this project because it is already complete. Notice to Public and Other Agencies Public noticing for this project is being done in accordance with noticing requirements and in public meetings held by the City of Brentwood GSA and others. Project 3: Dry-year Water Transfer ECCID/CCWD Project Summary Submitting GSA East Contra Costa Irrigation District Project Type Dry-Year Water Exchange Estimated Groundwater Offset and/or Recharge Up to 4,000 AFY EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-12 Under this project, CCWD diverts surface water of the same quantity ECCID has pumped from groundwater sources to meet local municipal and industrial demands within the ECC Subbasin. In wet years ECCID does not pump groundwater beyond what is required for use by ECCID direct use customers. This project is ongoing and implemented on an as needed basis and could be expanded if necessary to meet water supply needs while avoiding undesirable results. This exchange benefits local domestic supply as the aquifer recovers quickly through natural recharge and aids in meeting the measurable objective of maintaining average groundwater storage through all water year types. Although surface water meets about 85 percent of the ECC Subbasin water supply, groundwater can play a key role in prolonged droughts and benefit and preserve the agricultural resources of the region. ECCID will pump additional groundwater in dry years when surface waters are in a shortage as a result of drought. Measurable Objective Expected to Benefit: This project can help to avoid lowering groundwater levels and reduction in groundwater storage through replenishment of groundwater pumped during dry water years using surface water in wet water years. It also can help avoid depletion of interconnected surface water through taking stress of surface water supplies during dry years. Project Status and Timetable for Initiation and Completion: This project was first implemented in 2000 and is ongoing. The project will be implemented in dry years under an existing agreement. Required Permitting and Regulatory Process: The dry year transfer has been permitted and approved under the following agreements: • Contract Among the Department of Water Resources of the State of California, East Contra Costa Irrigation District, and Contra Costa Water District, 1991 (amended 2000). • Water Sales Agreement Between the East Contra Costa Irrigation District and the Contra Costa Water District, 2000. • DWR approved the dry year exchange in a letter dated May 22, 2003. Expected Benefits and Evaluation: This project helps ensure groundwater is made available and distributed fairly to as many users as possible in the Subbasin when needed. Although surface water meets about 85 percent of the ECC Subbasin water supply, groundwater can play a key role in prolonged droughts and benefit and preserve the agricultural resources of the region. Benefits will be evaluated through volumetric measurement of delivered water. How Project Will Be Accomplished/Evaluation of Water Source: ECCID will pump additional groundwater in dry years when surface waters are in a shortage as a result of drought. Currently a long-term agreement is in place to initiate the transfer in dry years. Implementation includes a monitoring plan that was approved by DWR. The source of water will be the ECCID which is expected to be reliable. At this time there are no exchanges scheduled. However, additional wells may be EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-13 considered to improve the efficiency of the groundwater transfer as well as to allow transfers outside of the irrigation season. Legal Authority: The dry year groundwater exchange is included in the Water Sales Agreement between ECCID and CCWD, dated February 22, 2000. Estimated Costs and Plans to Meet Costs: The initial implementation costs for this project have already been met by ECCID. Ongoing and future costs of the project are expected to be minimal and would be paid for by rate payers as needed. Circumstances for Implementation: For purposes of this transfer, a shortage situation must be determined when the U.S. Bureau of Reclamation notifies the CCWD that the allocation of Central Valley Water Project (CVP) water to CCWD will be less than CCWD’s requested schedule of water supply service, submitted pursuant to CCWD’s CVP contract. DWR will be informed when the transfer begins and ends. Total volumes of water will be reported monthly and annually to DWR per the existing agreements and approved monitoring plan. No further process is needed to determine the conditions which would require this project because it has already been implemented. Notice to Public and Other Agencies Public noticing for this project is being done in accordance with noticing requirements and in public meetings held by the ECCID GSA and others. Projects Under Construction Projects in this category are currently under construction and will be operating by 2042. Both projects provide in-lieu groundwater recharge benefits. The projected cumulative supply of these projects is 8,381 AFY. Project 4: Citywide Non-Potable Water Distribution System Project Summary Submitting GSA City of Brentwood Project Type In-Lieu Recharge / Recycled Water Estimated Groundwater Offset and/or Recharge Up to 1,661 AFY EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-14 This project consists of the expansion of the reclaimed (non-potable) water distribution system throughout the City to provide reclaimed water for irrigation of golf courses, parks, parkways, medians, and other applicable uses. There are parks and public landscaping that are currently irrigated using potable water. By converting to non-potable water usage, the City can save on potable water supply. This project will deliver an additional 1,661 AFY produced by its treatment plant and offset the use of potable water sourced in part from the Subbasin. Measurable Objective Expected to Benefit: This project, through increasing the city water supply, helps avoid potential lowering of groundwater levels, reduction in groundwater storage, and depletion of interconnected surface water. Project Status and Timetable for Initiation and Completion: This project is currently under construction. This project began February 16, 2021 and is on schedule to be completed by November 2021. Required Permitting and Regulatory Process: This project requires the installation of non-potable water main lines throughout various portions of Brentwood. The project is being funded by a State Water Resources Control Board Revolving Fund “SRF” loan, so project approvals were obtained from the Regional Water Quality Control Board (RWQCB) and other affected local agencies. Expected Benefits and Evaluation: Recycled water is an important part of the City’s water resources. Recycled water allows the City to conserve potable water, thereby ensuring a reliable water supply for current and future demand. The Non-Potable Water Distribution System project will expand the non-potable water distribution system and improve access to recycled water supplies. This project will create an additional 1,661 AFY in total water supply and offset groundwater pumping and dependence on surface water. Developing alternative water supplies is an important component of the requirements to achieve sustainable groundwater management and will be critical to maintaining long-term groundwater sustainability. Benefits will be evaluated through volumetric measurement of recycled water added back into the system. How Project Will Be Accomplished/Evaluation of Water Source: The City’s Wastewater Treatment Plant’s tertiary treatment and disinfection provides recycled water for landscaping. The City is a producer and distributor of Title 22 tertiary recycled water for unrestricted reuse. Upon completion of the pipeline installation, recycled water will be pumped throughout the City of Brentwood for irrigation uses in lieu of potable water. Since the source of water is recycled wastewater, this is expected to be reliable even during drought periods. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-15 Legal Authority: GSAs, in this case the City of Brentwood GSA, have the authority to plan and implement projects. Unrestricted, non-potable recycled water is defined as wastewater that has been treated to tertiary standards (via filtration and disinfection) that meet Title 22 of the California Code of Regulations (California Department of Public Health, 2018). The production and distribution of recycled water is covered in the City’s Master Reclamation Permit. Recycled water treated to this level can be used for all outdoor irrigation demands in a community, including parks, school grounds, street medians, residential landscaping, public open space, as well as industrial uses such as cooling water. Estimated Costs and Plans to Meet Costs: The estimated capital cost for this project is $9,054,036. The State approved an agreement with the City for utilization of the SRF to fund the City’s Recycled Water Project, which included the Citywide Non- Potable Water Distribution System project. The loan agreement also provides for a portion to be funded with grants from both Proposition 1 and Proposition 13. The final loan amount will be dependent upon final project costs, with the loan portion of the agreement to be repaid from Wastewater Enterprise and Wastewater Development Impact Fee funds over 30 years. Annual operating costs associated with this expansion project are minor because this is an improvement on existing City of Brentwood non-potable water system infrastructure, with operations already paid for by ratepayers. Circumstances for Implementation: The Brentwood City Council approved this project in August 2020. This project began on February 16, 2021. The City of Brentwood has developed preliminary planning documents to identify uses for recycled wastewater at both existing and future sites. The recycled wastewater will be used for the irrigation of parks and landscape amenities. The City of Brentwood already has constructed a portion of the recycled water distribution system and will continue to expand the system as the City grows. Recycled water demands are estimated to be 2,111 AF (688 MGY) at buildout. There is no process for determining the conditions which would require this project because it is already underway. Notice to Public and Other Agencies Public noticing for this project is being done in accordance with noticing requirements and in public meetings held the City of Brentwood GSA and others. Project 5: City of Antioch Brackish Water Desalination Project Project Summary Submitting GSA City of Antioch Project Type In-Lieu Recharge Estimated Groundwater Offset and/or Recharge Up to 6,720 AFY EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-16 This project improves water supply reliability by providing the production of up to 6 MGD of drinkable water utilizing high salinity water from the San Joaquin River that was previously untreatable via conventional treatment methods. Measurable Objective Expected to Benefit: This project, through increasing water supply, helps avoid potential lowering of groundwater levels, reduction in groundwater storage, and depletion of interconnected surface water. Project Status and Timetable for Initiation and Completion: Construction for this project began following a construction agreement for this work approved by the Antioch City Council on December 15, 2020. The project is currently under construction and expected to be completed in 2023. Required Permitting and Regulatory Process: This project includes the construction of a new intake from the San Joaquin River, modification to an existing water treatment plant, installation of approximately 4.5 miles of pipeline, and the introduction of brine in the discharge stream at the location of the wastewater treatment facility. The work will require permits from National Marine Fisheries Services (NMFS), California Department of Fish and Wildlife (DFW), Regional Water Quality Control Board (RWQCB), U.S. Army Corps of Engineers (USACE), State Department of Transportation (Caltrans), and Union Pacific Railroad (UPRR). All permits for this project have been obtained. Expected Benefits and Evaluation: Water supply reliability is a critical component of the GSP and will be important in maintaining the sustainability of the Subbasin. This project will introduce up to 6 MGD of new drinking water into the region, equivalent to providing water for 27,000 people per day 1. This water will be produced from high salinity source water from the San Joaquin River that is currently unusable, utilizing conventional treatment methods. The benefits will be evaluated based on volumetric measurement of the amount of treated water put into the system. How Project Will Be Accomplished/Evaluation of Water Source: The City of Antioch will continue to use its pre-1914 water rights to pump water from the San Joaquin River. The river pump station is currently permitted to pump up to 16 MGD from the river. As a pre-1914 right, this supply will be highly reliable. 1 In 2016 the Legislative Analyst’s Office estimates that the average residential water use was 85 gallons per person per day. The average number of people per household is 2.5 (average number of people per household in the United States from 1960 to 2019). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-17 Legal Authority: GSAs, in this case the City of Antioch GSA, have the authority to plan and implement projects. The City of Antioch will continue to use its pre-1914 water rights to pump water from the San Joaquin River. Construction of the new facilities will occur on existing City right-of-way or with new easements which have been acquired. Estimated Costs and Plans to Meet Costs: The estimated capital costs for this project total $110,000,000. Table 8-3 summarizes the funding sources for the project. Estimated annual operating costs of the project are between $2,100,000 and $4,000,000, depending on annual rainfall. Operating costs from the project will be paid for by ratepayers. Table 8-3. City of Antioch Brackish Water Desalination Project Funding Sources Source Amount ($) California Department of Water Resources Desalination Grant 10,000,000 State Water Resources Control Board Drinking Water Revolving Loan Fund Award 56,000,000 California Department of Water Resources Settlement Agreement Funds 27,000,000 City of Antioch Water Enterprise Funds 17,000,000 Circumstances for Implementation: A construction agreement for this work was approved by the Antioch City Council on December 15, 2020. The project is already underway and does not require any new conditions or approvals. Notice to Public and Other Agencies Public noticing and public meetings for this project have complied with all noticing requirements followed by the City of Antioch GSA and other participating agencies. Planned Projects Projects in this category are planned and are expected to be completed and operating by 2042. One project provides in-lieu groundwater recharge benefits, and the other provides water quality benefits. The projected cumulative supply of these projects is 2,800 AFY. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-18 Project 6: Treatment and Reuse of Alternative Water Supplies Project Summary Submitting GSA Diablo Water District Project Type In-Lieu Recharge / Recycled Water Estimated Groundwater Offset and/or Recharge Up to 2,800 AFY This project will offset current and future groundwater pumping. Through the introduction of recycled water for future park and public landscaping areas, future groundwater pumping in these areas is reduced. Additionally, through aquifer storage and recovery via indirect potable reuse, a drought-resilient water supply will be created to help limit groundwater drawdown during periods of drought. Measurable Objective Expected to Benefit: This project, by increasing water supply, will help to avoid potential lowering of groundwater levels, reduction in groundwater storage, and depletion of interconnected surface water. Project Status and Timetable for Initiation and Completion: The feasibility study phase is complete, and the project will move into the planning phase in late 2021. The timeline for initiation and completion is still under development, pending the final plan. It is anticipated to take between 5 and 10 years from the beginning of project construction to completion. Required Permitting and Regulatory Process: This project will require a CEQA review and permit from the SWRCB. Additional requirements may include County Well Permits, and City/County encroachment permits. Expected Benefits and Evaluation: This project will create up to 2,800 AFY reduction in future estimated aquifer extraction through availability of recycled water. This likely will increase as flows to the sanitary district increase due to regional growth. The yield will be evaluated through volumetric monitoring of recycled water delivered for parks and landscape use. Developing alternative water supplies is an important component of maintaining long-term groundwater sustainability. How Project Will Be Accomplished/Evaluation of Water Source: Currently, the GSA is in initial discussions with the sanitary district regarding funding, organization structure, responsibilities, etc. Each agency has created an ad hoc committee to assess ideas and bring to their full Boards for evaluation. Since the source of water would be recycled wastewater, this is expected to be reliable even during drought periods. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-19 Legal Authority: GSAs, in this case the Diablo Water District GSA, have the authority to plan and implement projects. Unrestricted, non-potable recycled water is defined as wastewater that has been treated to tertiary standards (via filtration and disinfection) that meet Title 22 of the California Code of Regulations (California Department of Public Health, 2018). This project may also involve the creation of a Joint Powers Agreement between DWD and Ironhouse Sanitary District (ISD). Estimated Costs and Plans to Meet Costs: The estimated capital costs for this project are expected to fall between $20 and $100 Million. A more precise estimate and the proposed method to cover this cost will be determined during the planning phase of the project, which will begin in late 2021. Circumstances for Implementation: This is a future action approved by both the sanitary board and the Diablo Water District Board. The project will be implemented following completion of the East Cypress Corridor. The decision to move forward will depend on confirmation of water supply availability from the project and desire to move forward from the stakeholders. Water supply availability and stakeholder desire will be determined during the planning phase. Unsustainable changes in aquifer conditions, while not expected, would accelerate the implementation of this project. Aquifer conditions will be monitored as described in Section 6. Notice to Public and Other Agencies Public noticing for this project is being done in accordance with noticing requirements and in public meetings held by the Diablo Water District GSA and others. Project 7: Transport Model Development Project Summary Submitting GSA Diablo Water District Project Type Water Quality Estimated Groundwater Offset and/or Recharge N/A, Water Quality Benefits This project will address the water quality measurable objective by expanding the existing surface water/groundwater flow model to include a solute transport component. The development of a solute transport component will complement the existing ECCSim modeling work completed for the GSP by allowing the simulation of the transport of chemicals within the East Contra Costa Subbasin. This will improve the understanding of the movement of water and constituents under various flow regimes including climate change, sea level rise, and changes in groundwater use. The current ECCSim platform does not directly support inclusion of a transport component, so this project would involve converting the IWFM model platform inputs to a MODFLOW platform, with various improvements necessary to facilitate solute transport. Particle tracking would be incorporated into the new MODFLOW model for the ECC Subbasin after sufficient refinement of lateral and vertical discretization, calibration, development of EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-20 climate change and sea level rise scenarios, and various additional future groundwater pumping regimes. The new flow and transport model would allow ECC to determine how chemicals could potentially be mobilized as a result of additional groundwater development, in order to avoid degradation of groundwater quality. This project would require converting the current ECCSim model to the MODFLOW platform and would include a detailed report, including maps, figures, charts, and tables describing the development of the model. This also would include developing the solute transport component and documenting the results of the modeling effort. Measurable Objective Expected to Benefit: This project will help to avoid degraded water quality concerns. Project Status: This project is currently in the planning phase. The timeline for implementation is still under development. It is anticipated to take about a year to complete. Required Permitting and Regulatory Process: No permits will be required for this project. Expected Benefits and Evaluation: The new model will increase the understanding about movement of poor-quality water within the Subbasin under various hydrologic conditions including climate change and sea level rise. This also will enhance the water quality monitoring described in Section 6. How Project Will Be Accomplished/Evaluation of Water Source: The project is currently in initial discussions with GSAs regarding funding, organizational structure, and responsibilities. Legal Authority: GSAs have the authority to plan and implement projects. Estimated Costs and Plans to Meet Costs: The estimated costs for this project are $250,000 to $500,000. The plans to cover these costs are currently under development. Circumstances for Implementation: This project would be implemented by the ECC Working Group. Implementation would begin when agreement about funding and potential grant money is secured. Water supply availability, political desire, and aquifer conditions are all motivating the desire to develop a transport model. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-21 Notice to Public and Other Agencies Public noticing for this project is being done in accordance with noticing requirements and in public meetings held the Diablo Water District GSA and others. 8.2 Management Actions Management actions are activities that GSAs may implement locally to achieve or maintain groundwater sustainability. These management actions are all “planned” and therefore are currently in the conceptual phase. GSAs will consider these management actions to address possible future threats to groundwater sustainability on an as-needed basis in potential areas of concern. They generally do not require outside approval or infrastructure and are part of the authorities granted to GSAs under SGMA legislation. As established in Section 7, groundwater conditions in the ECC Subbasin exhibit stability and sustainability. Basin-wide management actions are not currently proposed for GSP implementation, but future actions may be instituted by GSAs to address local concerns if they arise during the implementation and planning horizon. Some GSAs may implement management actions proactively as a local policy. If undesirable results occur or are projected to occur during the GSP implementation period, subsequent GSP updates will identify additional management actions and provide an implementation schedule as needed. Potential Management Actions The GSAs may elect to implement one or more potential management actions for maintaining sustainability in the Subbasin (or portion thereof). Table 8-4 lists the potential management actions included in this GSP. Generally, these management actions are not applicable to de minimis well users 2. De minimis well users are discussed further in Section 8.2.1.1. Management actions include well spacing control, oversight of well construction, reporting, and a potential demand management program. These potential management actions fall within the powers and authorities of GSAs under SGMA. 2 “De minimis extractor” means a person who extracts, for domestic purposes, two acre-feet or less per year. Section 10721, Water Code EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-22 Table 8-4. Summary of Potential Management Actions Name Type MO to Benefit Status Well Spacing Control Demand Management Groundwater Levels, Groundwater Storage, Land Subsidence Concept Oversight of Well Construction Features Water Quality Water Quality Concept Well Metering, Monitoring, and Reporting Improved Data / Demand Management Groundwater Levels, Groundwater Storage, Interconnected Surface Water, Land Subsidence Concept Demand Management Program Demand Management All Concept State Programs for Domestic Well Users Well Data Groundwater Levels, Groundwater Quality Concept Not listed under Table 8-4 are potential advocacy and engagement with other lead agencies that oversee activities that can have an impact on groundwater sustainability. Of particular concern expressed by the public and some GSAs is the risk posed by hazardous substances and oil and gas drilling. The presence of contamination and oil and gas activity in the ECC Subbasin are cited in Section 3.3.6. Although GSAs do not have authorities under SGMA to regulate such activities, they may seek to advise applicable agencies of potential risks to sustainability posed by projects and permitting actions. The basis for such engagement may include the subbasin hydrogeologic conceptualization which can provide a more current and robust risk assessment with respect to threats to groundwater. The next two subsections discuss non-applicability to de minimis users, and coordination with Contra Costa County which would be needed with these actions. The subsections following those summarize the potential management actions. Non-Applicability to De Minimis Users Management actions related to wells are generally not applicable to de minimis users. Primary exceptions may be made when certain well standards are needed to ensure source protection for the de minimis user and other users. A GSA may therefore impose standards for seal and intake depths where such standards are needed to avoid water quality degradation and are consistent with the sustainability goal and the sustainable management criteria detailed in Section 7. Where applicable, GSAs may seek to develop options to quantify groundwater pumping by de minimis users, including self-certification. This measure is strictly to provide better accuracy for projecting impacts and sustainability and is not intended to infringe on privacy or place any financial or other burden on this category of user. Information will be included in the GSP Data Management System described in Section 6. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-23 Coordination with Contra Costa County Implementation of any management action pertaining to new wells, excluding de minimis users, shall be coordinated with Contra Costa County. A management action that pertains to existing wells, such as a requirement to install a meter, would not involve County coordination but would be undertaken by a GSA in accordance with authorities and powers granted under SGMA. With regard to new wells, the County Environmental Health Division is the permitting authority for well siting (plot plan) and construction inspection. The latter includes a final surface inspection of the completed well. Coordination between the County permitting division and GSAs is recognized as a requirement for implementing future GSP management actions related to wells. If needed to ensure sustainability, existing well owners may be required to conform to well management actions such as metering or pumping limitations. These existing well owners may be identified through county records as part of the well inventory data gap discussed in Section 6. Since each GSA may implement a variety of requirements for new wells as a function of individual sustainable management responsibilities, the permitting process cannot anticipate every possible requirement that may be imposed by the GSAs. Nor is it expected that the County will inspect and regulate conformance to any GSA requirement for all permit applications. Rather, this GSP envisions that an administrative process be developed under which the County would notify well applicants of their responsibility to contact the appropriate GSA for local requirements involving siting, construction, and use of new wells. It would be the GSA’s responsibility to provide information on local requirements and a point of contact to ensure that well owners have a clear understanding of the purpose and execution of a requirement. The GSA, at its discretion, may perform inspections as it deems necessary to certify compliance with a particular requirement. Presently, the County permit process includes discretionary requirements only for additional water analyses and pump testing. The coordination with GSA requirements would require, as applicable, that a permit application identify any local GSA requirements and provide the certification at completion that such requirements were met. Measures such as ongoing reporting of pumped volumes would be the responsibility of the well owner. Any follow-up inspections or enforcement of a measure would be the responsibility of the GSA. This GSP recognizes that its management actions must be consistent with and subject to County authorities and responsibilities as the well permitting agency in the Plan area. It is expected that the process will be developed over two to three years commencing with implementation of the GSP in January 2022. Management Action 1: Well Spacing Control As determined by a GSA, well spacing control may be imposed to prevent a new well from causing a significant reduction in the production of any existing well in the vicinity. Sufficient well spacing, defined as the distance between the proposed new well and existing wells, would be required to mitigate the impacts of pumping interference (water level drawdown) induced by operation of the prospective new well to a less-than-significant degree. Determination of a significant impact shall be made by the GSA on a case-by-case basis considering, but not limited to, the number of wells potentially affected, the estimated effect on existing well production and cost, and the types and uses of the affected wells (e.g., domestic, agricultural, and industrial). The GSAs will seek to prioritize protection of disadvantaged EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-24 communities, rural domestic wells, agricultural uses, and environmental resources consistent with the Sustainable Management Criteria set forth in this GSP (see Section 7 ). Measurable Objective Expected to Benefit This management action would help to avoid lowering of groundwater levels, reduction in groundwater storage, and land subsidence by preventing significant drawdown. Management Action Status: This management action is currently conceptual and may be employed as needed by one or more GSAs. Required Permitting and Regulatory Process: No additional permitting would be required. Contra Costa County will notify new well permit applicants to identify and comply with the requirements of the applicable local GSA. Expected Benefits and Evaluation: The expected benefit is a reduction in groundwater level drawdown. Quantification of interference impacts may be made through direct measurements (well testing), calculations using applicable well hydraulic methods employed in groundwater science, or groundwater flow modeling. These methods shall use aquifer parameters consistent with the basin Hydrogeologic Conceptual Model described in Section 3 and incorporate flow rate and pumping duration as proposed by the well applicant. How Management Action Will Be Accomplished: If a determination that interference would result in a significant deleterious impact on the capacity of an existing well or wells, the well permit applicant may propose an alternate location that reduces the impact to a less than significant degree. The impact assessment and degree of significance may depend on numerous factors and shall be determined on a case-by-case basis by the GSA. Legal Authority: GSAs have the authority to plan and implement management actions. Each GSA in the Subbasin has the authority to implement and enforce this management action if needed based on aquifer conditions. Estimated Costs and Plans to Meet Costs: Since this management action is in the conceptual phase, specific costs are not yet determined. The costs would be associated with the number of new well permit applications in the Subbasin if the action is implemented. Circumstances for Implementation: Groundwater conditions are projected to remain at sustainable levels into the future under GSP implementation as described in Section 7. This management action may be implemented and would be monitored and quantified with respect to groundwater levels, as needed, if sustainable groundwater EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-25 levels cannot be maintained in any areas of the Subbasin during GSP implementation. This will be determined by the methods described in Section 6. Notice to Public and Other Agencies Public noticing for this management action would be done in accordance with noticing requirements and in public meetings held by the GSA or GSAs which elect to implement this management action. Additionally, Contra Costa County will notify new well permit applicants to identify and comply with the requirements of their GSA. Management Action 2: Oversight of Well Construction Features A GSA may impose requirements for well construction to ensure that a new well does not induce adverse impacts to water quality and availability. Such requirements may include specifying depths for well seals and intake screens to avoid commingling of zones with differing water quality where such commingling may lead to degradation of the water supply. A GSA may also institute construction standards that exceed local and state requirements where it has been determined that such standards are needed to protect water quality for conditions in the GSA plan area. Measurable Objective Expected to Benefit This management action would help to avoid degraded water quality concerns through more locally targeted well construction requirements. Management Action Status: This management action is currently conceptual and may be employed as needed by one or more GSAs. Required Permitting and Regulatory Process: No additional permitting would be required. Contra Costa County will notify new well permit applicants to identify and comply with the requirements of the applicable local GSA. Expected Benefits and Evaluation: The expected benefit is the protection of water quality. Water quality will be monitored using the methods described in Section 6. How Management Action Will Be Accomplished: The GSA or GSAs which elect to implement this management action would work with the County well permitting office to ensure new well permit holders are aware of construction requirements. The GSAs will also establish and/or develop with the County a process for inspecting well construction activities and ensuring requirements are met. Legal Authority: GSAs have the authority to plan and implement management actions. Each GSA in the Subbasin has the authority to implement and enforce this management action if needed based on aquifer conditions. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-26 Estimated Costs and Plans to Meet Costs: Since this management action is in the conceptual phase, specific costs are not yet determined. The costs would be associated with the number of new well permits sought in the Subbasin if the action is implemented. Circumstances for Implementation: Groundwater conditions are projected to remain at sustainable levels into the future under GSP implementation, as described in Section 7. This management action may be implemented and would be monitored and quantified with respect to water quality, as needed, if sustainable conditions are not maintained in any areas of the Subbasin during initial GSP implementation. This will be determined by the methods described in Section 6. Notice to Public and Other Agencies Public noticing for this management action would be done in accordance with noticing requirements and in public meetings held by the GSA or GSAs which elect to implement this management action, if needed. Additionally, Contra Costa County will notify existing and new well permit applicants to identify and comply with the requirements of their GSA. Management Action 3: Well Metering, Monitoring, and Reporting A fundamental requirement for sustainable groundwater management is quantification of a water budget and continual updating of predictive tools, such as groundwater flow models, used to assess water supply availability under future water demands, land-use changes, climate change, and sea level rise. To meet this need, a GSA may impose metering, monitoring, and reporting requirements for new and existing wells. Measurable Objective Expected to Benefit By providing better data on water budgets, this management action would help to avoid the potential lowering of groundwater levels, reduction in groundwater storage, depletion of interconnected surface water, and land subsidence. Management Action Status: This management action is currently conceptual and may be employed as needed by one or more GSAs. Required Permitting and Regulatory Process: No additional permitting would be required. Contra Costa County will notify new well permit applicants to identify and comply with the requirements of the applicable local GSA. Implementation of this management action for existing wells (i.e., after a well is constructed under a County permit) shall be done by the GSA in accordance with its authorities and powers under SGMA. Expected Benefits and Evaluation: The expected benefit is more accurate estimation of groundwater extraction in the Subbasin. This will enhance the planned monitoring programs described in Section 6. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-27 How Management Action Will Be Accomplished: The GSA or GSAs which elect to enforce this management action would work with the County well permitting office to ensure new and existing well permit holders are aware of monitoring and reporting requirements. The GSAs would also establish a process for inspecting and ensuring that monitoring and reporting requirements are met, and/or work with the County to establish a process. Legal Authority: GSAs have the authority to plan and implement management actions. Each GSA in the Subbasin has the authority to implement and enforce this management action if needed based on aquifer conditions. Estimated Costs and Plans to Meet Costs: Since this management action is in the conceptual phase, specific costs are not yet determined. The costs would be associated with the number of wells located in the area or areas requiring this management action. Circumstances for Implementation: Groundwater conditions are projected to remain at sustainable levels into the future under GSP implementation, as described in Section 7. This management action may be implemented and would be monitored and quantified with respect to groundwater conditions, as needed, if sustainable conditions are not maintained in any areas of the Subbasin during initial GSP implementation. This will be determined by the methods described in Section 6. Some GSAs may implement metering and reporting of existing and new wells proactively as a local policy. Notice to Public and Other Agencies Public noticing for this management action would be done in accordance with noticing requirements and in public meetings held by the GSA or GSAs which elect to implement this management action, if needed. Additionally, Contra Costa County will notify new well permit applicants to identify and comply with the requirements of their GSA. Management Action 4: Demand Management Program The planned PMAs described in this Section will be pursued by the ECC Subbasin GSAs to maintain sustainable groundwater conditions. The GSAs have also included a potential demand management program to avoid undesirable results as a “backstop” to other PMAs. Events that may trigger this management action include, but are not limited to severe, prolonged drought conditions resulting in groundwater levels approaching MT or MO in specific parts of the Subbasin; other PMAs are not achieving the expected level of benefits; or new information about projected future conditions show that sustainability objectives will not be met. Demand management broadly refers to any water management activity that reduces the consumptive use of water. To be effective for purposes of sustainable groundwater management, demand management must result in a reduction in net groundwater pumping (pumping net of recharge). Activities that, for example, reduce canal seepage or reduce deep percolation from irrigation will not be effective. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-28 They may decrease quantity of water diverted or applied but they also reduce recharge to usable groundwater, so do not improve the net pumping from the aquifer. For purposes here, a demand management action is one that incentivizes, enables, or possibly requires water users to reduce their consumptive use, but does not dictate exactly how users have to do it. Agricultural users can respond to demand management by changing to lower water-using crops, water-stressing crops (providing less water than the crop would normally consume for full yield), reducing evaporation losses, and reducing irrigated acreage. Urban users can respond to demand management through lower water-using landscapes, reducing evaporative losses, or reducing landscape requiring irrigation. The ECC member water agencies have a range of options for implementing demand management, if required. These would only be included as part of GSP implementation as needed in any areas where sustainable groundwater conditions are not maintained. Through reducing overall water demand, this action would potentially provide a benefit to all measurable objectives. General types of demand management programs include: • Allocation. An allocation may be directly coupled with pumping limits. Under an allocation, the different sources of groundwater are quantified and allocated to individual parcels, wells, or entities (such as, for example, farming operations). By defining the quantities of groundwater available to individuals, this can incentivize reductions in use and development of new recharge opportunities. An allocation is a rigid method for implementing demand management. It effectively limits water use on a well, parcel, or operation basis. This could require idling land or switching crop or landscape on lands that have insufficient allocation to meet irrigation demand, which imposes costs on water users (e.g., growers). There are ways to increase the flexibility of allocations to reduce the costs of demand management. For example, the allocation could be defined as an average over a period of time rather than a fixed amount every year, or users could be allowed to carry over unused allocation into the next year. • Allocation + Water Market. An allocation that is less than historical water use can be coupled with a water market. A groundwater market is another way to increase the flexibility of an allocation to reduce costs of demand management. A market is an institution that allows willing buyers and sellers to exchange groundwater allocation (“credits”). More broadly, a market creates a means to exchange allocation with another groundwater user, whether for a single season or using a multi-year trade. Willing sellers trade a part of their allocation to willing buyers in exchange for a payment that the seller expects will exceed the return he/she would have earned from using the water for irrigation. This additional flexibility reduces the cost to the GSA’s users of achieving demand reduction under an allocation. Development of a water market institution is a complex process that encompasses more than defining the groundwater allocation. This investigation would be initiated by the GSAs in the future, if needed. • Land Repurposing. Land repurposing programs are more targeted than an allocation or market program but maintain flexibility for participants by its voluntary nature. Such a program would provide a financial incentive to willing participants for their currently irrigated lands to be repurposed into other, non-irrigated uses. Programs can focus on short-term drought conditions, EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-29 or they can provide multi-year reductions in demand if that is needed under some conditions. For longer-term programs, lands can be repurposed to achieve other multi-benefit objectives - for example, to create habitat corridors or to support local endangered species. • Other financial incentives. Demand management can also be achieved through a range of other financial incentives. This could include positive financial incentives to reduce consumptive groundwater use. It could also include groundwater extraction fees that disincentivize groundwater use. Measurable Objective Expected to Benefit Depending on how the demand management program is structured, it has the potential to benefit all measurable objectives in the ECC Subbasin. Management Action Status: This management action is currently conceptual and would only be employed as needed by one or more GSAs. Required Permitting and Regulatory Process: No additional permitting would be required. Expected Benefits and Evaluation: The expected benefit is preventing lowering of groundwater levels and reduction in groundwater storage, where and when this may be needed. Water quality and other benefits may also be present depending on the specific program deployed. These will be monitored as described in Section 6. How Management Action Will Be Accomplished: The GSA or GSAs that elect to implement a demand management program would first initiate a study for the program design. This would include assessing program goals, incentives, and potential program structure. It would also involve substantial stakeholder outreach and engagement. Program design would include an assessment of the economic impacts of alternative demand management strategies to identify ways to minimize costs to individuals, businesses, and the regional economy in affected areas. Legal Authority: GSAs have the authority to plan and implement management actions. Each GSA in the Subbasin has the authority to implement and enforce this management action if needed based on aquifer conditions. Estimated Costs and Plans to Meet Costs: Since this management action is in the conceptual phase, specific costs are not yet determined. Costs would be assessed as part of the demand management program design. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-30 Circumstances for Implementation: Groundwater conditions are projected to remain at sustainable levels into the future under GSP implementation, as described in Section 7. This management action would be implemented and would be monitored and quantified with respect to groundwater conditions, as needed, if and only if sustainable conditions are not maintained in any areas of the Subbasin during GSP implementation. This will be determined by the methods described in Section 6. Notice to Public and Other Agencies Public noticing for this management action would be done in accordance with noticing requirements and in public meetings held by the GSA or GSAs which elect to implement this management action, if needed. Additionally, and as appropriate depending on the structure of the program, Contra Costa County will notify new well permit applicants to identify and comply with the requirements of their GSA. Management Action 5: State Programs for Domestic Well Users A GSA may engage existing and developing state programs to monitor and strengthen resiliency of domestic well users including DACs and vulnerable populations that use groundwater. They are located at the following links: • https://mydrywell.water.ca.gov/report/shortage_resources • https://mydrywell.water.ca.gov/report/ • https://water.ca.gov/Programs/Groundwater-Management/Drinking-Water-Principles Measurable Objective Expected to Benefit This management action would help to identify significant and unreasonable impacts from lowering of groundwater levels, reduction in groundwater storage, and degradation of groundwater quality. Management Action Status: This management action is currently conceptual and will be employed by one or more GSAs to enhance outreach and information exchange with key groundwater users in the basin. Required Permitting and Regulatory Process: No additional permitting would be required. Expected Benefits and Evaluation: The expected benefit is reporting of groundwater level drawdown and degradation of groundwater quality. These programs may be expanded in the future and would be incorporated into Annual Reports. How Management Action Will Be Accomplished: GSAs will notify their constituency that these programs are available. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-31 Legal Authority: GSAs have the authority to plan and implement management actions. Each GSA in the Subbasin has the authority to provide the information in this management action if needed desired. Estimated Costs and Plans to Meet Costs: No costs are expected at this time. Circumstances for Implementation: If constituents are concerned about sustainability and protection of drinking water, GSAs would seek to facilitate participation in these state programs Notice to Public and Other Agencies Public noticing for this management action would be done in accordance with noticing requirements and in public meetings held by the GSA or GSAs which elect to implement this management action. Other Water Conservation Actions The ECC member water agencies have a full range of existing water conservation policies and programs promoting efficient water use. Like the other management actions listed, these would be included as part of GSP implementation as needed in any areas where sustainable groundwater conditions are not maintained. The various conservation efforts proposed by different GSAs and other agencies could provide benefits to all measurable objectives, as needed. Some of these actions are ongoing or have been implemented previously, while others are in the conceptual or planning phase. Additional permitting should not be required for any of these actions, and the County will notify new well permit applicants to identify and comply with the requirements of their GSA. Benefits to groundwater levels would be monitored using the methods described in Section 6. Specific costs have not been established for actions in the conceptual phase. For those that are planned or already implemented, costs beyond what the agencies already incur should be minimal. Groundwater conditions are projected to remain at sustainable levels into the future under GSP implementation, as described in Section 7. However, if sustainable levels are not maintained in any areas of the Subbasin during initial GSP implementation, management actions may be implemented and their effects would be monitored and quantified with respect to groundwater conditions, as needed. This will be determined by the methods described in Section 6. Public noticing for these actions would be done in accordance with noticing requirements and in public meetings held by the GSA or GSAs which elect to implement the actions as part of the GSP, if needed. Additionally, Contra Costa County will notify new well permit applicants to identify and comply with the requirements of their GSA. Table 8-5 summarizes key water conservation efforts listed by GSA in corresponding Urban Water Management Plans and Agricultural Water Management Plans. Plans include those listed for the City of Antioch, City of Brentwood, Diablo Water District, Town of Discovery Bay Community Services District, BBID, and CCWD. While CCWD is not a GSA, the District has several water conservation plans. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-32 Table 8-5. Summary of Water Conservation Programs Listed in Urban Water Management Plans and Agricultural Water Management Plans Programs City of Antioch1 City of Brent-wood1 Diablo Water District2 Discovery Bay3 BBID4 CCWD5 Water Waste Prevention Ordinances X X X X X X Metering X X X X X X Conservation Pricing X X X X X X Public Education and Outreach X X X X X X Programs to Assess Management Distribution System Real Loss X X X X X X Water Conservation Program and Coordination Staffing Support X X X X X X Increasing Water Order Flexibility X Providing for Availability of Water Management Services X X Rebates for Lawn Replacements X 1. Brown and Caldwell (2021) 2. CDM Smith (2021) 3. LSCE (2021) 4. CH2M (2017) 5. CCWD (2021) EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 8 - PROJECTS AND MANAGEMENT ACTIONS LSCE 8-33 8.3 References Brown and Caldwell. 2021. Final 2020 Urban Water Management Plan. Prepared for City of Antioch. May 2021. Brown and Caldwell. 2021. Draft 2020 Urban Water Management Plan. Prepared for City of Brentwood. May 2021. Contra Costa Water District. 2021. Draft 2020 Urban Water Management Plan. April 2021. CDM Smith (CDM). 2021. Draft 2020 Diablo Water District Urban Water Management Plan. May 2020. CH2M.2017.Byron Bethany Irrigation District Agricultural Water Management Plan. Prepared for Byron Bethany Irrigation District. October 2017. East County Water Management Association. 2019. East Contra Costa County Integrated Regional Water Management Plan, Update 2019. March 2019 Legislative Analyst’s Office (LAO). 2017. Residential Water Use TRENDS AND Implications for Conservation Policy. https://lao.ca.gov/Publications/Report/3611#top.Accessed June 2021. Luhdorff and Scalmanini, Consulting Engineers. 2021. Draft 2020 Urban Water Management Plan Town of Discovery Bay Community Services District. March 2021. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-i SECTION 9 CONTENTS 9 Plan Implementation ...............................................................................................................9-1 9.1 Estimate of GSP Implementation Costs ..................................................................................... 9-1 9.1.1 GSA Administration ............................................................................................................ 9-2 9.1.1.1 Public Outreach .............................................................................................................. 9-2 9.1.1.2 Legal Services ................................................................................................................. 9-2 9.1.2 GSP Implementation .......................................................................................................... 9-3 9.1.2.1 Implementation Agreement .......................................................................................... 9-3 9.1.2.2 Grant Writing ................................................................................................................. 9-3 9.1.2.3 Internal Coordination and Meetings .............................................................................. 9-3 9.1.3 GSP Updates ....................................................................................................................... 9-3 9.1.3.1 Response to DWR Comments on the ECC GSP .............................................................. 9-3 9.1.3.2 Annual Reports ............................................................................................................... 9-3 9.1.3.3 Periodic (5-year) Assessments ....................................................................................... 9-4 9.1.3.4 GSP Studies .................................................................................................................... 9-4 9.1.4 Monitoring and Data Management ................................................................................... 9-5 9.1.4.1 Monitoring of Wells ....................................................................................................... 9-5 9.1.4.2 Metering and Monitoring Water Use ............................................................................ 9-5 9.1.4.3 Data Management System ............................................................................................. 9-6 9.1.4.4 Well Inventory Program ................................................................................................. 9-6 9.1.5 Contingency ....................................................................................................................... 9-6 9.2 GSA Implementation Costs ........................................................................................................ 9-7 9.2.1 Byron-Bethany Irrigation District GSA ............................................................................... 9-8 9.2.2 City of Antioch GSA ............................................................................................................ 9-8 9.2.3 City of Brentwood GSA ....................................................................................................... 9-9 9.2.4 Contra Costa Water District ............................................................................................... 9-9 9.2.5 County of Contra Costa GSA ............................................................................................ 9-10 9.2.6 Diablo Water District GSA ................................................................................................ 9-11 9.2.7 Discovery Bay Community Services District GSA ............................................................. 9-11 9.2.8 East Contra Costa Irrigation District GSA ......................................................................... 9-12 9.3 GSP Funding and Financing ...................................................................................................... 9-13 9.4 Schedule for Implementation .................................................................................................. 9-14 9.5 Initial and Subsequent Annual Reporting ................................................................................ 9-17 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-ii 9.5.1 General Information (§356.2(a)) ...................................................................................... 9-17 9.5.2 Subbasin Conditions (§356.2(b)) ...................................................................................... 9-18 9.5.3 Plan Implementation Progress (§356.2(c)) ...................................................................... 9-18 9.5.4 GSP Annual Report Module ............................................................................................. 9-18 9.6 Periodic (5-Year) Evaluation and Reporting ............................................................................. 9-19 9.6.1 Sustainability Evaluation (§356.4(a) - §356.4(d)) ............................................................. 9-19 9.6.2 Monitoring Network Description (§356.4(e)) .................................................................. 9-20 9.6.3 New Information (§356.4(f)) ............................................................................................ 9-20 9.6.4 GSA Actions ((§356.4(g) - §356.4(h)) ............................................................................... 9-20 9.6.5 Plan Amendments, Coordination, and Other Information (§356.4(i) - §356.4(k)) .......... 9-21 LIST OF TABLES Table 9-1 ECC GSP Estimated Joint Implementation Costs…………………………………………………………..9-4 Table 9-2 ECC GSP Estimated Total of Individual GSA Implementation Costs………………………………9-7 Table 9-3 BBID GSA Implementation Costs…………………………………………………………………………………9-8 Table 9-4 City of Antioch GSA Implementation Costs…………………………………………………………………..9-9 Table 9-5 City of Brentwood GSA Implementation Costs……………………………………………………………..9-9 Table 9-6 CCWD Implementation Costs…………………………………………………………………………………….9-10 Table 9-7 County of Contra Costa GSA Implementation Costs……………………………………………………9-10 Table 9-8 DWD GSA Implementation Costs………………………………………………………………………………9-11 Table 9-9 Discovery Bay Community Services District GSA Implementation Costs……………………..9-12 Table 9-10 ECCID GSA Implementation Costs……………………………………………………………………………..9-12 Table 9-11 Potential Funding and Financing Sources for GSP Implementation……………………………9-13 LIST OF FIGURES Figure 9-1 General Schedule of 20-year ECC GSP Plan Implementation……………………………………….9-15 Figure 9-2 ECC Subbasin Estimated Capital Outlay for Projects……………………………………………………9-16 Figure 9-3 ECC Subbasin Estimated Annual Costs for Project O&M and GSA Implementation…….9-17 APPENDICES Appendix 9a East Contra Costa Groundwater Sustainability Plan Implementation Budget EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-1 9 PLAN IMPLEMENTATION This section outlines the schedule and costs to implement the Groundwater Sustainability Plan (GSP) over the first five years and discusses implementation effects in accordance with GSP regulations, CCR §354.6(e) and §354.8(f)(3), in addition to the annual and 5-year evaluation reporting in accordance with GSP regulations CCR §356.2 and §356.4. The implementation plan is based on the hydrogeologic conceptual model of the East Contra Costa Subbasin (Subbasin) (Section 3), current and projected water demands (Section 4), and the projected water budget (Section 5). Estimated costs are developed to meet GSP regulations and to implement PMAs under Section 8. Costs include annual and 5-year reports as required under GSP regulations (CCR §356.2 and §356.4). To achieve the Subbasin sustainability goal by 2042 and avoid undesirable results through 2072 as required by SGMA and the GSP regulations, a range of Projects and Management Actions (PMAs) will be developed and implemented by the GSAs. Section 8 describes each PMA, gross benefit, project capital and operating costs, and how it will be implemented. This section describes: • Costs for GSAs to administer GSP activities (not including the project-specific costs described in Section 8), as required by CCR § 354.6(e). • Financing approaches. • Timeline for implementing all GSA PMAs between 2022 and 2042. • Monitoring and reporting, including the contents of annual reports and 5-year periodic evaluations that the GSAs must provide to DWR (CCR §356.2 and §356.4). 9.1 Estimate of GSP Implementation Costs The seven GSAs and Contra Costa Water District (CCWD) are exploring whether amendments to the existing MOU, new MOU or other cooperative agreement will be used to administer and implement the ECC GSP.It is anticipated that an annual operating budget will be established that is considered for approval by each GSA. The initial development of the GSP was funded by the GSAs and CCWD with help from grant funding under Proposition 1. No fees have been charged to landowners and water users in the Subbasin. It is anticipated that funding and financing sources—including potential fees—will be developed to cover the costs of GSP implementation, development of PMAs, annual reports, and 5-year periodic evaluations of the GSP. Groundwater management fees, as authorized through SGMA, may be adopted by GSAs based on their needs and applicable to their jurisdictions only. Implementation of the GSP includes project and management actions discussed in Section 8 and the following: • GSA Administration: Public Outreach, Legal Services, and other tasks. • GSP Implementation: Implementation Agreement, Grant Writing, Internal Coordination and Meetings. • GSP Updates: Addressing Comments from DWR on the GSP, Annual Reports, Periodic (5-year) Evaluations, GSP Studies. • Monitoring and Data Management: Monitoring of Wells, Metering and Monitoring Water Use, DMS. • Contingency EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-2 The following subsections describe these cost components in greater detail and the estimated costs for these activities are summarized in Section 9.2. In this section, costs are not included for project development or implementation. It is anticipated that each GSA will generate revenue to cover its PMA costs using its available legal authorities. 9.1.1 GSA Administration Administration may be performed through outside services, agency staff, or a combination. Administrative costs generally include record keeping, bookkeeping, continued outreach to stakeholders, legal services, government relations, and general management. GSA administration also includes project and contract management for external services for GSP implementation and technical studies for PMAs. It is anticipated that some administrative tasks will have a lead GSA. 9.1.1.1 Public Outreach Each GSA will conduct public outreach and engagement to provide timely information to stakeholders regarding GSP progress and Subbasin conditions. A GSP Working Group will meet regularly to inform participating agencies and the public regarding implementation activities and reporting. Any changes in administration and management will be conducted through a public process in which stakeholders will be engaged for input into the decision-making process. The GSP Working Group will routinely meet at a regular frequency to be determined through the implementation agreement to implement the GSP. The Working Group will provide information to the public about GSP implementation and the status of groundwater sustainability in the Subbasin. The GSP website 1 will be maintained as a communication tool for posting updated groundwater level time series graphs, reports, meeting information, technical updates and data analyses. Other outreach starting in 2022 includes an electronic newsletter, board notifications, and inter- and intra-Subbasin coordination. Most GSAs have included public outreach costs under general GSA Administration, however, others include public outreach as part of GSP Implementation costs. Therefore, GSP implementation costs vary across GSAs for public outreach activities (Section 9.1.2). 9.1.1.2 Legal Services The ECC Working Group currently receives in-kind legal services from Contra Costa County on an as- needed basis. If legal services are needed on issues requiring specific expertise in groundwater, SGMA compliance, or other specialized matters, the ECC Working group may engage outside counsel. Costs for such services are not currently anticipated and are not included in the current budget estimates. Any legal costs would be authorized separately by the GSP Working Group on an as-needed basis. GSA legal services costs included in the GSP are for general legal review and retainers. 1 https://www.eccc-irwm.org/about-sgma EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-3 9.1.2 GSP Implementation The GSAs will be responsible for GSP implementation. The GSAs implementing the ECC Subbasin GSP anticipate this will involve substantial coordination across GSAs for technical tasks. For example, many planned PMAs require coordination between one or more GSAs. The overall Subbasin sustainability depends on continued coordination, planning, and evaluation of groundwater conditions. The lead GSA, or GSAs, for each implementation task will keep the other GSAs informed through periodic updates to stakeholders, the public, the GSP Working Group, and any other ad-hoc committees. 9.1.2.1 Implementation Agreement The GSAs and CCWD will enter into a joint implementation agreement after the GSP is approved by DWR. Cost sharing to fund GSP implementation, as described in this section, will be part of the joint agreement. 9.1.2.2 Grant Writing DWR and other agencies may release solicitation packages for grants to assist medium priority subbasins in funding PMA development and GSP implementation. The GSP Working Group will review future grant solicitations from DWR and other state and federal agencies and be responsible for grant writing and submission. The Working Group may engage outside services to assist in grant writing. It is anticipated that the GSAs may also engage outside services to implement grant activities (e.g., development of planned PMAs). 9.1.2.3 Internal Coordination and Meetings The GSP Working Group will meet at a regular frequency to be determined through the Implementation agreement to implement the GSP. GSAs will regularly hold board meetings, committee meetings, and other public meetings throughout the year to discuss updates and ongoing initiatives. 9.1.3 GSP Updates In addition to finalizing the GSP, GSP regulations require submittal of annual reports and 5-year GSP assessment reports to DWR. The elements of these reports shall comply with DWR technical guidance and requirements and be made available to the public. 9.1.3.1 Response to DWR Comments on the ECC GSP As applicable, responses or revisions to the GSP based on DWR review comments will be made and authorized through the GSP Working Group. 9.1.3.2 Annual Reports Annual reports will be submitted to DWR starting on April 1, 2022. The contents of the report are detailed in Section 9.5 below. Annual reports will be available to ECC Subbasin stakeholders on the ECC GSP website. The reports may be prepared by a technical consultant, agency staff designated by the GSP Working Group, or a combination of the two. The estimated cost of the annual report is presented in Table 9-1 based on typical rates for technical consulting services. GSAs expect that annual reports will also require inter- and intra-GSA coordination as well as stakeholder outreach. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-4 Table 9-1. ECC GSP Estimated Joint Implementation Costs Cost Category 2022 2023 2024 2025 2026 Community Outreach & Education $10,000 to $25,000 $10,000 to $25,000 $10,000 to $25,000 $10,000 to $25,000 $10,000 to $25,000 Monitoring and Data Management $45,000 $45,000 $45,000 $45,000 $45,000 GSP Updates1 $33,000 to $50,000 $33,000 to $50,000 $48,000 to $65,000 $48,000 to $65,000 $140,000 to $500,000 Grant Writing $25,000 $25,000 $25,000 $25,000 $25,000 Contingency $11,300 to $14,500 $11,300 to $14,500 $12,800 to $16,000 $12,800 to $16,000 $22,000 to $59,500 Total $124,300 to $159,500 $124,300 to $159,500 $140,800 to $176,000 $140,800 to $176,000 $242,000 to $654,500 1. Annual reports and 5-Year Update. 9.1.3.3 Periodic (5-year) Assessments Periodic (5-year) GSP assessment reports will be submitted to DWR starting in 2027. The GSAs will evaluate the GSP at least every five years to assess whether GSP implementation is achieving the sustainability goal for the Subbasin. The contents for this report are detailed in Section 9.5 below. The estimated cost of the 5-year evaluations is presented in Table 9-1 based on typical rates for technical consulting services. In contrast to the annual report, this report requires additional evaluation of sustainability conditions, objectives, monitoring, and documentation of new information that is available since the last update to the GSP. It may also include substantial updates to the GSP, if monitoring of groundwater conditions show that the GSP is not achieving the sustainability goal. GSAs expect that periodic evaluations will also require significant inter- and intra-GSA coordination and stakeholder outreach. 9.1.3.4 GSP Studies GSP implementation will require various planning, technical, and economic/financial studies. These are additional costs that are not covered by the cost of specific PMAs (see Section 8). For example, this may include planning studies for proposed PMAs and studies to assess and allocate PMA and GSP implementation costs. GSAs will also need to continue to monitor PMAs to assess their benefit, update implementation, and coordinate with stakeholders and other GSAs. This may include modifying PMAs to ensure the Subbasin meets its sustainability objectives. These reports and analyses may be prepared by a technical consultant, agency staff designated by the GSP Working Group, or a combination of the two. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-5 9.1.3.4.1 Planning Studies GSAs may develop planning studies to integrate the GSP with other regional water management efforts, monitor Subbasin conditions, and update the GSP to ensure that the Subbasin continues to meet all sustainability objectives. GSAs will continue to evaluate Subbasin conditions and may adjust short- and long-term Subbasin planning efforts accordingly. Other planning studies may include evaluating projects and developing other programs to support sustainable management. 9.1.3.4.2 Technical Evaluations Annual and 5-year reports will require additional technical analysis. GSAs will continue to monitor data pertaining to sustainability indicators in the Subbasin to document progress toward sustainability objectives. Additional monitoring wells may be installed in an adaptive process, and GSAs will evaluate and report groundwater conditions, water use, and change in groundwater storage as required by DWR. GSAs will continue to evaluate data gaps and implement programs to improve data quality and applicability. 9.1.3.4.3 Economic/Financial Analyses GSAs may develop economic and fiscal studies to support implementation of PMAs and the overall GSP. This may include feasibility assessments for proposed projects, or to support development of grant applications. Other financial analyses may include rate studies and supporting technical analysis required to implement fees or assessments to cover costs. GSAs would engage legal and technical experts to help develop the required studies. 9.1.4 Monitoring and Data Management Monitoring of the six sustainability indicators as described in Sections 6 and 7 shall be performed as part of the GSP implementation. Section 6 identifies the monitoring networks for the ECC GSP and Section 7 describes the management criteria for SGMA sustainability indicators. The ECC GSP monitoring networks incorporate existing monitoring conducted by the GSAs and other agencies. The GSAs will continue their individual monitoring programs as outlined in Section 6 to satisfy the requirements under the GSP. The ECC GSP does not fund these individual monitoring efforts and these costs are not included in the overall cost to implement the GSP. 9.1.4.1 Monitoring of Wells Monitoring and well maintenance costs reported in Section 9.2 include four new well installations that are required to fill data gaps discussed in Section 6. Additionally, appendix 9a gives a detailed table of monitoring costs of the new wells. 9.1.4.2 Metering and Monitoring Water Use Some GSAs may introduce a program to meter and monitor groundwater pumping. Costs reported by the GSAs would be associated with direct costs to the individual GSA. The capital and operating costs associated with the flow meters and monitoring equipment will be determined at the time of adoption by the GSA. Costs may be borne by the well owner or another entity other than the GSA or could be funded under future grant opportunities from state or federal sources. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-6 9.1.4.3 Data Management System Data from the various monitoring sources is included in the DMS discussed in Section 6. The DMS will be updated with monitoring network data and will be used to prepare reports made publicly available on the ECC GSP website. The DMS will be used for analysis and will be presented in various forms to enhance interpretation and to demonstrate basin conditions with respect to sustainability indicators. As required by DWR, certain data will be uploaded to the SGMA portal twice per year. 9.1.4.4 Well Inventory Program As discussed in Section 6, a well inventory program shall be created to be completed by the first 5-year GSP evaluation and report. The well inventory will be developed as a tool to better understand how GSP implementation is affecting groundwater sustainability in the Subbasin. The process of creating a well inventory will be coordinated with the Contra Costa County which is the permitting agency for new wells in the ECC Subbasin. A procedure for sharing information on all new wells constructed under the County’s permitting authority with the ECC Subbasin Data Management System shall be developed. The well inventory system will track various parameters including: • Well location (physical address) and GIS coordinates • Date installed • Permit number (County) • Well Drillers Report number (DWR) • Depth of well • Well diameter • Depths of perforations • Use (domestic, industrial, commercial, agricultural, other) A method to incorporate wells constructed prior to implementation of the new data exchange system will be evaluated with the objective that the DMS substantially accounts for active wells in the Subbasin to serve the sustainable management goals as detailed in Section 7. 9.1.5 Contingency An additional GSA contingency cost is included for planning purposes. This may include actions needed to respond to critically dry years or if Subbasin conditions start trending towards minimum threshold levels in any area. The GSA budgets include a 10-percent annual contingency to account for unanticipated expenses (see Table 9-1). This is in addition to other contingency costs identified and reported by some GSAs. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-7 9.2 GSA Implementation Costs This section summarizes GSP implementation activities and estimated budgets for the first five years of GSP implementation. This does not include PMAs that are discussed in Section 8. The estimated 5-year budget for total GSA implementation costs is between $2.4 and $3.0 million. The estimated annual cost is between $450,000 and $480,000 for most years and could be in excess of $1 million during years when 5- year evaluations and reports are prepared. There also are expected to be additional costs in 2024 and 2025 to address DWR review comments. GSA implementation costs will be paid for through contributions from the member GSAs and CCWD under a cost-sharing arrangement to be developed following GSP adoption. Annual costs for individual GSAs will vary and generally be higher in years when 5-year evaluations and reports are prepared. There are two components of GSA Implementation costs in the ECC Subbasin: joint implementation costs, which will be shared by the member GSAs, and individual costs for each of the GSAs. Joint implementation costs are summarized in Table 9-1. Details are available in Appendix 9a. These costs generally are for services provided to complete necessary tasks associated with implementation, including outreach, monitoring, data management, reporting and grant writing. Cost sharing between the GSAs will be determined prior to execution of the joint implementation agreement. There are some uncertainties regarding the joint costs, particularly for the costs to prepare the 5-year evaluation and reports. Therefore, ranges are reported for many of the joint cost categories and totals in Table 9-1. Table 9-2 summarizes the estimated total of individual GSA implementation costs across all GSAs (and CCWD) by year. This is followed by subsections summarizing costs by agency. All costs are preliminary estimates based on the information available as of GSP development. GSAs will evaluate funding needs, opportunities, and update budget projections periodically. Table 9-2. ECC GSP Estimated Total of Individual GSA Implementation Costs Cost Category 2022 2023 2024 2025 2026 GSA Administration $118,550 $111,772 $112,003 $112,245 $122,829 GSP Implementation $71,539 $71,836 $72,145 $72,467 $88,450 GSP Updates $19,516 $19,598 $19,683 $19,771 $43,363 Monitoring and Implementation $62,015 $62,015 $62,015 $62,015 $62,015 Contingency $48,362 $47,722 $47,785 $47,850 $57,866 Total $319,982 $312,943 $313,631 $314,348 $374,523 Other costs borne by each of the GSAs are presented in the following subsections. These costs reflect local needs and engagement that are unique to each agency’s area and may change based on future assessment of conditions in the subbasin. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-8 9.2.1 Byron-Bethany Irrigation District GSA The Byron-Bethany Irrigation District GSA (BBID) estimates that annual implementation costs will be approximately $47,860 per year over the next five years (Table 9-3). GSA Administration includes public outreach and legal services. GSP Implementation includes public outreach, internal coordination, committee meetings, and board meetings. GSP Updates includes GSP document review. Monitoring and Implementation covers well monitoring, metering water use, and DMS costs. Contingency includes GSP management and legal services. The budget also includes a 10-percent annual contingency to account for unanticipated expenses. These costs do not include project-specific costs, described in Section 8, nor costs to build and operate additional PMAs that may be required if the GSA determines that its sustainability objectives are not being met. BBID will recover GSP implementation costs through grants and local revenues that are yet to be determined. The GSA is currently evaluating options. Section 9.3 provides a general description of how BBID and other GSAs may recover GSP implementation costs. Table 9-3. BBID GSA Implementation Costs Cost Category 2022 2023 2024 2025 2026 GSA Administration $22,000 $22,000 $22,000 $22,000 $22,000 GSP Implementation $11,920 $11,920 $11,920 $11,920 $11,920 GSP Updates $1,000 $1,000 $1,000 $1,000 $1,000 Monitoring and Implementation $2,950 $2,950 $2,950 $2,950 $2,950 Contingency $9,987 $9,987 $9,987 $9,987 $9,987 Total $47,857 $47,857 $47,857 $47,857 $47,857 9.2.2 City of Antioch GSA The City of Antioch GSA estimates that annual implementation costs will be approximately $17,600 per year over the next five years (Table 9-4). GSA Administration includes public outreach and legal services. GSP Implementation includes public outreach, internal coordination, committee meetings, and board meetings. Monitoring and Implementation covers well monitoring, metering water use, and DMS costs. The budget also includes a 10-percent annual contingency to account for unanticipated expenses. These costs do not include PMA-specific costs, described in Section 8, nor costs to build and operate additional projects or management actions that may be required if the GSA determines that its sustainability objectives are not being met. The City of Antioch GSA will recover GSP implementation costs through grants and local revenues that are yet to be determined. The GSA is currently evaluating options. Section 9.3 provides a general description of how City of Antioch GSA and other GSAs may recover GSP implementation costs. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-9 Table 9-4. City of Antioch GSA Implementation Costs Cost Category 2022 2023 2024 2025 2026 GSA Administration $4,500 $4,500 $4,500 $4,500 $4,500 GSP Implementation $8,000 $8,000 $8,000 $8,000 $8,000 Monitoring and Implementation $3,500 $3,500 $3,500 $3,500 $3,500 Contingency $1,600 $1,600 $1,600 $1,600 $1,600 Total $17,600 $17,600 $17,600 $17,600 $17,600 9.2.3 City of Brentwood GSA The City of Brentwood GSA estimates that annual implementation costs will be approximately $13,500 per year over the next five years (Table 9-5). GSA Administration includes public outreach and legal services. GSP Implementation includes public outreach. Monitoring and Implementation covers well monitoring. The budget also includes a 10-percent annual contingency to account for unanticipated expenses. These costs do not include project-specific costs, described in Section 8, nor costs to build and operate additional projects or management actions that may be required if the GSA determines that its sustainability objectives are not being met. The City of Brentwood GSA will recover GSP implementation costs through grants and local revenues that are yet to be determined. The GSA is currently evaluating options. Section 9.3 provides a general description of how the City of Brentwood GSA and other GSAs may recover GSP implementation costs. Table 9-5. City of Brentwood GSA Implementation Costs Cost Category 2022 2023 2024 2025 2026 GSA Administration $6,130 $6,130 $6,130 $6,130 $6,130 GSP Implementation $3,065 $3,065 $3,065 $3,065 $3,065 Monitoring and Implementation $3,065 $3,065 $3,065 $3,065 $3,065 Contingency $1,226 $1,226 $1,226 $1,226 $1,226 Total $13,486 $13,486 $13,486 $13,486 $13,486 9.2.4 Contra Costa Water District CCWD, although not a GSA, will be active in GSP implementation and will therefore incur associated costs. CCWD estimates that annual implementation costs will be approximately $7,000 per year over the next five years (Table 9-6). GSA Administration includes public outreach. GSP Implementation includes internal coordination, committee meetings, and board meetings. GSP Updates include GSP document review. The budget also includes a 10-percent annual contingency to account for unanticipated expenses. These costs do EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-10 not include project-specific costs, described in Section 8, nor costs to build and operate additional projects or management actions that may be required if the CCWD determines that its sustainability objectives are not being met. CCWD will recover GSP implementation costs through grants and local revenues that are yet to be determined. CCWD is currently evaluating options. Section 9.3 provides a general description of how CCWD and the GSAs may recover GSP implementation costs. Table 9-6. CCWD Implementation Costs Cost Category 2022 2023 2024 2025 2026 GSA Administration $1,257 $1,295 $1,333 $1,373 $1,415 GSP Implementation $3,769 $3,882 $3,998 $4,118 $4,242 GSP Updates $966 $995 $1,025 $1,055 $1,087 Contingency $599 $617 $636 $655 $674 Total $6,591 $6,789 $6,992 $7,201 $7,418 9.2.5 County of Contra Costa GSA The County of Contra Costa GSA estimates that annual implementation costs will be approximately $33,000 per year over the next five years (Table 9-7). Annual costs are projected to be higher when a 5- year evaluation and report is prepared. GSA Administration includes public outreach and legal services. GSP Implementation includes public outreach, internal coordination, committee meetings, and board meetings. The budget also includes a 10-percent annual contingency to account for unanticipated expenses. These costs do not include PMA-specific costs, described in Section 8, nor costs to build and operate additional projects or management actions that may be required if the GSA determines that its sustainability objectives are not being met. The County of Contra Costa GSA will recover GSP implementation costs through grants and local revenues that are yet to be determined. The GSA is currently evaluating options. Section 9.3 provides a general description of how the County of Contra Costa GSA and other GSAs may recover GSP implementation costs. Table 9-7. County of Contra Costa GSA Implementation Costs Cost Category 2022 2023 2024 2025 2026 GSA Administration $13,988 $6,988 $6,988 $6,988 $15,317 GSP Implementation $18,610 $18,610 $18,610 $18,610 $25,256 Contingency $3,260 $2,560 $2,560 $2,560 $4,057 Total $35,858 $28,158 $28,158 $28,158 $44,630 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-11 9.2.6 Diablo Water District GSA DWD estimates that annual implementation costs will be approximately $140,400 per year over the next five years (Table 9-8) and $164,650 in 2026 when the 5-year evaluation and report will be prepared. GSA Administration includes public outreach, legal services, and staff time. GSP Implementation includes public outreach, internal coordination, committee meetings, and board meetings. GSP Updates include GSP document review, which will be higher in years when a 5-year assessment is prepared. Monitoring and Implementation covers well monitoring, metering water use, and DMS costs. Contingency includes GSP management and legal services, plus a 10-percent annual contingency to account for unanticipated expenses. These costs do not include project-specific costs, described in Section 8, nor costs to build and operate additional projects or management actions that may be required if the GSA determines that its sustainability objectives are not being met. DWD will recover GSP implementation costs through grants and local revenues that are yet to be determined. The GSA is currently evaluating options under its current legal authorities. Section 9.3 provides a general description of how DWD and other GSAs may recover GSP implementation costs. Table 9-8. DWD GSA Implementation Costs Cost Category 2022 2023 2024 2025 2026 GSA Administration $60,000 $60,000 $60,000 $60,000 $60,000 GSP Implementation $10,500 $10,500 $10,500 $10,500 $10,500 GSP Updates $7,500 $7,500 $7,500 $7,500 $25,000 Monitoring and Implementation $36,000 $36,000 $36,000 $36,000 $36,000 Contingency $26,400 $26,400 $26,400 $26,400 $33,150 Total $140,400 $140,400 $140,400 $140,400 $164,650 9.2.7 Discovery Bay Community Services District GSA The Discovery Bay Community Services District GSA estimates that annual implementation costs will be approximately $10,000 per year over the next five years (Table 9-9). GSA Administration includes public outreach and legal services. GSP Implementation includes public outreach, internal coordination, committee meetings, and board meetings. GSP Updates includes GSP document review. The budget also includes a 10- percent annual contingency to account for unanticipated expenses. These costs do not include project- specific costs, described in Section 8, nor costs to build and operate additional projects or management actions that may be required if the GSA determines that its sustainability objectives are not being met. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-12 Discovery Bay Community Services District GSA will recover GSP implementation costs through grants and local revenues that are yet to be determined. The GSA is currently evaluating options. Section 9.3 provides a general description of how Discovery Bay Community Services District GSA and other GSAs may recover GSP implementation costs. Table 9-9. Discovery Bay Community Services District GSA Implementation Costs Cost Category 2022 2023 2024 2025 2026 GSA Administration $3,675 $3,859 $4,052 $4,254 $4,467 GSP Implementation $3,675 $3,859 $4,052 $4,254 $4,467 GSP Updates $1,050 $1,103 $1,158 $1,216 $1,276 Contingency $840 $882 $926 $972 $1,021 Total $9,240 $9,703 $10,188 $10,696 $11,231 9.2.8 East Contra Costa Irrigation District GSA The East Contra Costa Irrigation District GSA (ECCID) estimates that annual implementation costs will be approximately $49,000 per year over the next five years (Table 9-10), and $67,650 in FY 2026 when the 5-year evaluation and report will be prepared. GSA Administration includes public outreach and legal services. GSP Implementation includes public outreach, internal coordination, committee meetings, and board meetings. GSP Updates includes GSP document review. The budget also includes a 10-percent annual contingency to account for unanticipated expenses. These costs are all expected to be higher in 2026 when the 5-year evaluation and report will be prepared. Monitoring and Implementation covers well monitoring, metering water use, and DMS costs. These costs do not include PMA-specific costs, described in Section 8, nor costs to build and operate additional projects or management actions that may be required if the GSA determines that its sustainability objectives are not being met. ECC ID will recover GSP implementation costs through grants and local revenues that are yet to be determined. The GSA is currently evaluating options. Section 9.3 provides a general description of how the ECC ID and other GSAs may recover GSP implementation costs. Table 9-10. ECCID GSA Implementation Costs Cost Category 2022 2023 2024 2025 2026 GSA Administration $7,000 $7,000 $7,000 $7,000 $9,000 GSP Implementation $12,000 $12,000 $12,000 $12,000 $21,000 GSP Updates $9,000 $9,000 $9,000 $9,000 $15,000 Monitoring and Implementation $16,500 $16,500 $16,500 $16,500 $16,500 Contingency $4,450 $4,450 $4,450 $4,450 $6,150 Total $48,950 $48,950 $48,950 $48,950 $67,650 EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-13 9.3 GSP Funding and Financing Administering the GSP and monitoring and reporting progress is projected to cost approximately $360,000 per year on average across all Subbasin GSAs and CCWD. Costs are projected to be higher during years in which a 5-year periodic evaluation and report is prepared, and slightly lower during other years when an annual report is prepared. This does not include the capital and annual operating cost of PMAs (see Section 8). Covering the costs of PMAs and general GSP implementation requires evaluating both financing and funding sources. Financing relates to identifying sources of capital (typically bonds and bank loans) to pay for project capital expenses. Funding relates to sources of money required to cover capital repayment (pay back the debt financed projects) as well as project O&M, GSA administration, and other annual expenses. The agencies in the ECC Subbasin have the powers and authority to impose fees and assessments and may pursue other financing sources for capital projects and funding sources for repayment of debt, operations, and other ongoing expenses. The GSAs also have explicit fee authorities under SGMA legislation (Water Code §10730 and §10730.2). Table 9-11 summarizes potential financing and funding sources that may be used by GSAs for GSP implementation. Individual GSAs will create their own funding and financing plans to address their portion for the cost share, considering the options available to them. Table 9-11. Potential Funding and Financing Sources for GSP Implementation Capital Financing Considerations State (DWR) Grants (Prop. 68 and future bonds) Solicitations are typically targeted to general types of projects and specific benefits that are in the State’s interest US Bureau of Reclamation WaterSmart Grants Project-specific funding that can support planning studies (e.g., water market strategy grants) Other targeted potential grant programs (e.g., AB 252) Potential for multi-benefit projects Local bond issuance Local borrowing based on agency authority Private borrowing Current low interest rate environment may make these options attractive State or Federal low interest loans This could include future bond funded loan programs Funding Sources Considerations Fee – General General options for legal authority pre- and post-GSP development: Prop. 26, Prop. 218, Water Code §10730, Water Code §10730.2 Regulatory Fee Typically, pre-GSP fee that is related to regulatory cost. Prop. 26 and Water Code §10730 Service Fee Related to cost of service. Prop 218 and Water Code §10730.2. Subject to majority protest vote Special Tax Subject to 2/3 majority approval vote Special Benefit Special benefit assessment subject to majority protest vote EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-14 The ECC Subbasin has been successful in pursuing past grant funding (e.g., Sustainable Groundwater Planning Grant programs). The GSAs will pursue grant opportunities to fund this GSP implementation and local infrastructure projects. The initial funding for GSP implementation will be provided by the seven GSAs and CCWD through a joint agreement. GSA annual budgets will be reviewed, revised if needed, and approved by the GSAs based on interpreted basin conditions, past actual expenditures, and the immediate future needs. The budget will be adjusted over time as the GSP implementation costs are better understood through sustainable management activities and guidance from DWR on the submitted GSP and subsequent reporting. 9.4 Schedule for Implementation The GSP implementation schedule allows time for GSAs to develop and implement PMAs and meet all sustainability objectives by 2042. While some sustainability projects began immediately after SGMA became law and are already contributing to Subbasin goals, the GSAs will begin implementing all other planned GSP activities by 2022. Many PMAs will be implemented adaptively on an as-needed basis as explained in Section 8. A general implementation schedule showing the major tasks and estimated timeline during the 20 years of GSP implementation is provided in Figure 9-1. This includes key implementation tasks, projects that are either completed or currently under construction, and required reporting. Projects in the planning phase and management actions detailed in Section 8 are not included because these are going to be implemented on as needed basis, and likely would not occur if the Subbasin continues to exhibit stable and sustainable conditions. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-15 Figure 9-1. General Schedule of 20-year ECC GSP Plan Implementation Task Name 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 Plan Implementation GSP Submittal to DWR x Joint Implementation Agreement x Outreach and Communication Monitoring and DMS Projects (Completed or Under Construction) NE Antioch Annexation Non-Potable Storage and Pump Station Dry-Year Water Transfer Brentwood Non-Potable Distribution Antioch Brackish Water Desalination GSP Reporting Annual Reports x x x x x x x x x x x x x x x x x 5-year GSP Evaluation Reports x x x x x Indicates a submittal. Indicates ongoing event. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-16 The capital cost of each project and management action is summarized and discussed in more detail in Section 8. Figure 9-2 illustrates the capital outlay required to implement all of the PMAs specified in the GSP that are completed or are under construction. The figure indicates the year that the projects would be completed and begin operation, not when all the capital cost would be incurred. The total capital cost of all these projects equals approximately $136 million. These capital costs do not include the cost of management actions which would be implemented on an as-needed basis. Figure 9-2. ECC Subbasin Estimated Capital Outlay for Projects As projects are implemented, GSAs will incur annual operation and maintenance (O&M) costs. Figure 9-2 illustrates the estimated annual O&M costs (in current dollars) for all GSP projects described in Section 8 and the GSA annual costs described in Section 9.2. Average annual operating costs for projects increase from $21,500 per year in 2022 to over $3 million per year in 2023 when the City of Antioch Brackish Water Desalination Project is expected to go online. Project costs will be refined by GSAs as the GSP is implemented. GSA costs total about $0.3 million per year from 2021 to 2025 and over $0.4 million in 2026 when a 5-year evaluation and report is prepared. $0 $20 $40 $60 $80 $100 $120 2020 2021 2022 2023Capital Outlay ($ in millions) EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-17 Figure 9-3. ECC Subbasin Estimated Annual Costs for Project O&M and GSA Implementation 9.5 Initial and Subsequent Annual Reporting Pursuant to CCR §356.2, an annual report shall be submitted to DWR each year by April 1 following adoption of a GSP. The first ECC Subbasin GSP Annual Report is due April 1, 2022 and will cover the period October 1, 2019 through September 30, 2021 and will be annually thereafter. DWR has provided forms and instructions for submitting the materials electronically through the DWR online reporting system 2. The GSP Annual Report contains both a narrative description and data in DWR provided templates. The following subsections provide an overview of the basic contents for the Annual Report. 9.5.1 General Information (§356.2(a)) General information includes an executive summary discussing any significant findings or recommendations from the reporting period. Additionally, it will include a map showing the Subbasin and GSA boundaries. 2 https://sgma.water.ca.gov/portal/#gsp $0.0 $0.5 $1.0 $1.5 $2.0 $2.5 $3.0 $3.5 $4.0 2021 2022 2023 2024 2025 2026Annual Costs ($ in millions)Total Project O&M Cost GSA Implementation Costs EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-18 9.5.2 Subbasin Conditions (§356.2(b)) The subbasin conditions section of the annual report will provide an update on groundwater and surface water conditions in the Subbasin. This will include: • Groundwater Elevation: o Groundwater elevation contour maps by aquifer zone to depict the seasonal high (winter/spring) and seasonal low (late summer/fall). o Groundwater elevation hydrographs which illustrate water-year type and incorporate historical data. • Groundwater Extraction: o A table summarizing groundwater extractions by GSAs, estimates of groundwater use by sector (urban, agricultural, industrial, managed wetlands, managed recharge, and native vegetation), measurement method (direct or estimated), and accuracy of the measurements. o A map of the general location and quantities of groundwater extractions. • Surface Water Supply: • Surface water volume supplied by water source type (e.g., Central Valley Project, State Water Project, Colorado River Project, local supplies, local imported supplies, recycled water, desalination, and others). • Total Water Use: • Total water use by source and water use sector. • Changes in Groundwater Storage: o Map of the change in groundwater storage for each principal aquifer in the Subbasin. o A graph of historical to the present period showing water-year type, groundwater use, annual change in groundwater storage, and the cumulative change in groundwater storage for the Subbasin. 9.5.3 Plan Implementation Progress (§356.2(c)) The annual report will include a statement of the progress of the GSP implementation with milestones, significant updates or changes, implementation schedule, and implementation tasks and costs which will be reviewed, discussed, and updated as necessary. 9.5.4 GSP Annual Report Module All parts of the ECC GSP Annual Report are uploaded through the SGMA Portal consisting of the following parts: • Part A. Groundwater Extractions excel file: volume extracted by water use sector (e.g., urban, industrial, agricultural, managed wetlands, managed recharge, native vegetation, and other). • Part B. Groundwater Extraction Methods excel file: volume extracted by methods (e.g., meters, electrical records, land use, groundwater model, or other). • Part C. Surface Water Supply excel file: water supply volume by water source type (e.g., Central Valley Project, State Water Project, Colorado River Project, local supplies, local imported supplies, recycled water, desalination, and other). EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-19 • Part D. Total Water Use excel file: total water use volume by water use sector and by water source type. • Part E. Change in Storage. • Part F. Monitoring Network Module: information updated as needed. • Part G. GSP Annual Report PDF and GSP Annual Report Elements Guide Template: upload the GSP Annual Report pdf and populate the Elements Guide template. • Part H. GSP Annual Report Submittal. 9.6 Periodic (5-Year) Evaluation and Reporting The GSP will be evaluated every five years in accordance with CCR §356.4, with interim evaluations made in response to significant hydrologic changes or exceedances of minimum thresholds as discussed above. The periodic evaluation will be provided to DWR and shall include elements of the annual reports, GSP implementation progress, and progress toward meeting the sustainability goal of the Subbasin. The periodic evaluations will be available to interested parties and the public through the DWR website. The following subsections summarize what will be included in the periodic evaluation and report. 9.6.1 Sustainability Evaluation (§356.4(a) - §356.4(d)) An evaluation and description of current groundwater conditions will be included for each applicable sustainability indicator relative to the measurable objectives, interim milestones, minimum thresholds, and undesirable results. A summary of interim milestones and measurable objectives will be included, along with an evaluation of groundwater elevations in relation to minimum thresholds. If any minimum thresholds are found to be exceeded, the GSAs will investigate probable causes and implement actions to correct conditions, as warranted. However, exceedance of a minimum threshold does not automatically trigger corrective action, as the exceedance may be due to factors beyond the control of the GSA. As established in Section 7, groundwater conditions in the ECC Subbasin exhibit stability and sustainability, so this scenario is unlikely. Projects described in Section 8 will be evaluated to determine their implementation status, success, and progress toward reaching the GSP sustainability goal. If projects or management actions are not performing as expected, and in the unexpected case that sustainable conditions are not maintained in the Subbasin, the update will describe steps the GSAs will take to implement additional projects or demand management. Any changes to the implementation schedule of PMAs will be described in the periodic evaluation. Elements of the GSP will be evaluated for any potential reconsiderations or revisions, which will be proposed in the periodic evaluation. The sustainability indicators will be evaluated for undesirable results, and minimum thresholds and measurable objectives will be reconsidered with revisions proposed, if necessary. Evaluation will include the progress of the GSP toward meeting the sustainability goal and interim milestones. If conditions become worse than projected because any projects or management actions are not implemented according to the specified timeline, the deviation from the original plan will be documented and to the extent possible, corrective actions will be taken to speed implementation if necessary. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-20 Each periodic evaluation will include an assessment of the basin setting in relation to any significant or unanticipated changes or new information that may have developed during the evaluation period. Also, land uses and economic conditions will change in ways that cannot be anticipated at this time. As such, it may be necessary to revise the GSP to account for these changes. The elements of the GSP including the basin setting, management areas, undesirable results, minimum thresholds, and measurable objectives will be reconsidered by the GSAs during the periodic evaluations. Any proposed revisions will be documented in the periodic evaluation. 9.6.2 Monitoring Network Description (§356.4(e)) A description of the established ECC Subbasin Monitoring Network will be provided in the periodic evaluation and will include a description of potential data gaps, areas within the basin that are represented by data that does not meet the Data and Reporting Standards set by SGMA, and an assessment of the monitoring network functionality. If necessary, the evaluation will include actions necessary to improve the monitoring network, identification of data gaps, a program to acquire additional data sources (and the timing of such), and a plan to install new data collection facilities. 9.6.3 New Information (§356.4(f)) GSAs will continuously monitor Subbasin conditions, and the DMS will allow GSAs to identify additional data gaps and implement procedures to secure additional data. Land use and economic incentives for farming and other water uses in the Subbasin will continue to change as the GSP is implemented. GSAs expect that new information about groundwater conditions, PMAs, and sustainability objectives will continue to be available. Any significant, new information that has been developed since GSP adoption, amendment or the last periodic evaluation will be discussed, and will indicate whether new information warrants changes to any aspect of the GSP, including the basin setting, measurable objectives, minimum thresholds, or undesirable results. 9.6.4 GSA Actions ((§356.4(g) - §356.4(h)) The evaluation will include a description of any relevant actions taken by the GSAs since the last periodic or 5-year assessment including any regulations or ordinances related to the GSP, development of new PMAs, substantial changes in land use, and other actions impacting the implementation of the GSP. Within their allowed authorities, GSAs are evaluating new regulations or ordinances that could be implemented to help maintain sustainable conditions in the Subbasin. The 5-year periodic evaluation will include a summary of state laws and regulations, or local ordinances related to the GSP that have been implemented since the previous periodic evaluation and address how these may require updates to the GSP. Enforcement or legal actions taken by the GSAs in relation to the GSP will be summarized along with how such actions support sustainability in the Subbasin. The effect on any aspect of the GSP, including the basin setting, measurable objectives, minimum thresholds, or undesirable results will be described. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 9 - PLAN IMPLEMENTATION LSCE 9-21 9.6.5 Plan Amendments, Coordination, and Other Information (§356.4(i) - §356.4(k)) The evaluation will include a description of any completed or proposed Amendments to the GSP. This will also include a summary of amendments that are being considered or developed at that time. Any changes to the basin setting, measurable objectives, minimum thresholds, or undesirable results will be described. Any changes to the GSA coordination agreement, or other Subbasin coordination agreements will be documented and summarized. If necessary, a description of the coordination of GSAs within the Subbasin, coordination between hydrologically connected subbasins, and land use agencies will be presented. The Periodic Evaluation will include any other appropriate and relevant information pursuant to SGMA, GSP Implementation, and DWR review. The first 5-year GSP update and evaluation of sustainable management are due in 2027. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 10 - NOTICE AND COMMUNICATION LSCE 10-i SECTION 10 CONTENTS 10. Notice and Communication (§ 354.10) .................................................................................... 10-1 10.1 Description of Beneficial Uses and Users of Groundwater in the Basin .................................. 10-1 Interest Groups ................................................................................................................ 10-1 ECC GSP Advisory Groups ................................................................................................ 10-3 10.2 List of Public Meetings Where the GSP was Discussed............................................................ 10-3 Informational Public Meetings on ECC GSP ..................................................................... 10-3 Outreach Presentations to Community Groups .............................................................. 10-5 10.3 Comments on the GSP and a Summary of Responses ............................................................. 10-5 10.4 Decision-Making Process ......................................................................................................... 10-5 10.5 Opportunities for Public Engagement and How Public Input and Response was Used ...... 10-5 10.6 Encouraging Active Involvement ............................................................................................. 10-7 10.7 Informing the Public on GSP Implementation Progress .......................................................... 10-7 10.8 Interbasin Coordination ........................................................................................................... 10-7 LIST OF TABLES Table 10-1 List of Public Information Meetings and Outreach on the Draft ECC Subbasin……………10-4 Table 10-2 Public Comment Period for each GSP Section…………………………………………………………….10-6 APPENDICES Appendix 10a Summary List of Public Meetings and Outreach Appendix 10b Summary of Public Comments on the Draft ECC GSP and Responses Appendix 10c ECC Subbasin Communications Plan EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 10 - NOTICE AND COMMUNICATION LSCE 10-1 10. NOTICE AND COMMUNICATION (§ 354.10) The ECC Subbasin is governed by seven Groundwater Sustainability Agencies (GSAs) with the active participation of the Contra Costa Water District (Figure 1-2). As public agencies, each offers public engagement as part of their decision-making processes. A Memorandum of Understanding guided the development of this East Contra Costa (ECC) Groundwater Sustainability Plan (GSP). As part of this effort an agency Working Group and a Communications Committee were formed to advise the GSP development. The ECC GSP Working Group will continue to meet, at minimum, quarterly during GSP implementation. 10.1 Description of Beneficial Uses and Users of Groundwater in the Basin The Water Code Section 10723.2 requires the GSAs to consider the interests of all beneficial uses and users of groundwater, as well as those responsible for implementing the GSP. These interests include, but are not limited to, the following: 1. Holders of overlying groundwater rights, including: a. Agricultural users, including farmers, ranchers, and dairy professionals. b. Domestic well owners. 2. Municipal well operators. 3. Public water systems. 4. Local land use planning agencies. 5. Environmental users of groundwater. 6. Surface water users where there is a hydrologic connection between surface and groundwater bodies. 7. The federal government, including, but not limited to, the military and managers of federal lands. 8. California Native American tribes. 9. Disadvantaged communities, including, but not limited to, those served by private domestic wells or small community water systems. a. Entities listed in Section 10927 that are monitoring and reporting groundwater elevations in all or a part of the ECC Subbasin. Interest Groups The ECC Working Group considered each type of interested parties named by SGMA to determine if they were represented in the Subbasin and to include them in the outreach for the GSP. Agricultural Users: In 2015, agriculture was the primary land use covering 41 percent of the Subbasin. The agricultural sector is primarily served by surface water provided by BBID and ECCID and individual water rights to divert surface water on the delta islands. Both BBID and ECCID are members of the ECC GSP Working Group. Their service areas make up 37 percent of the agricultural land use. Domestic Well Users: Private residential well owners are estimated to pump approximately 600 afy (Table 4-2) from the Subbasin. Private well owner water use is primarily for residential, landscape, and some small-scale farming and livestock. To be considered a de minimis user, one well can pump up to two afy. Private well owner interests are represented by the GSAs that include de minimis users in their area. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 10 - NOTICE AND COMMUNICATION LSCE 10-2 Small Water Systems: About 22 small water systems as described in Section 2.1.1.3 use approximately 500 af (Table 4-2) of groundwater pumped every year from the Subbasin. The small public water systems in the Subbasin are represented by Contra Costa County and by the individual GSAs where the systems are located. Large Public and Municipal Well Operators: As discussed in more detail in Section 2.1.1.3, there are four public water systems (PWS) in the Subbasin: The City of Brentwood (a municipal well operator), Diablo Water District, and the Town of Discovery Bay. The City of Antioch is the fourth municipal PWS, but it does not supply groundwater to customers. Most of the water supplied by the City of Brentwood and Diablo Water District is surface water. The Town of Discovery Bay supply is entirely groundwater. The ECC Working Group includes representatives from the City of Antioch and all three of the systems that use groundwater. Local Land Use Agencies: Four entities in the ECC Subbasin have land use authority: Contra Costa County, the City of Antioch, the City of Brentwood, and the City of Oakley (water provided by DWD). All four entities (DWD for Oakley) are GSAs and participate in the ECC Subbasin Working Group. Environmental Users: The Subbasin has a generous supply of surface water due to the Bay-Delta setting and includes creeks and streams that are connected to shallow groundwater. The creeks, streams, and shallow groundwater discharge to the Bay-Delta. Environmental users of groundwater include species and habitat reliant on instream flows, wetlands and GDEs. GDEs are mapped in Figures 3-26a and 3-26b in Section 3.3.9. All vegetative species in the ECC Subbasin are listed in Table 3-4. Critical habitat for species in the ECC Subbasin is shown on Figure 3-27. Groups interested in environmental restoration of habitats and species within the Subbasin (e.g., Friends of Marsh Creek and DWR that manages Dutch Slough tidal marsh restoration) were called and/or emailed requesting input on the draft sections of this GSP. Surface Water Users with a Connection to Groundwater: The Subbasin includes several streams that are connected to groundwater in some of their reaches. Marsh Creek is connected to groundwater in part of its watershed, but surface water and groundwater use are limited to individual private users along the creek. Many properties along the creek are served by the City of Brentwood Public Works. Federal Government: Federal lands in the Subbasin include two small parcels in the City of Antioch (Figure 2-3) and are represented by the City of Antioch GSA. California Native American tribes: There are no tribal lands within the Subbasin (see Section 2.1.1.4). However, the GSAs formally contacted the Native American Heritage Commission 1 to verify any potential interests. Additional targeted outreach was made to tribes or tribal representatives with a potential interest due to historic use of subbasin lands for gathering and other traditional practices. Disadvantaged Communities: The disadvantaged areas (DAs) are described in Section 2.3.2. The total DAs population in the Subbasin is approximately 35,600 (Table 2-5). All DAs are served by small water systems, municipal water, or individual domestic wells (Figures 2-13a and 2-13b). SGMA has limited authority with regards to water quality improvements related to drinking water beneficial uses. Despite these limitations, GSAs represent the interests of the DAs (e.g., the City of Antioch, DWD, Contra Costa County, 1 Native American Heritage Commission, 1550 Harbor Blvd., Ste. 100, West Sacramento, CA 95691, (916) 373-3710. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 10 - NOTICE AND COMMUNICATION LSCE 10-3 and the City of Brentwood). The interests of the DAs are reflected in the sustainability goal and sustainable management criteria described in Section 7. Entities Monitoring and Reporting Groundwater Elevations: The ECC GSP Working Group members are the main entities that monitor groundwater elevations and conduct testing of groundwater quality in the Subbasin (see Section 2.2.1). Groundwater contamination sites report groundwater levels and water quality testing results through requirements set forth by other regulatory agencies and can be accessed via GeoTracker. ECC GSP Advisory Groups The ECC GSP Working Group was established in 2015 after SGMA legislation was passed. The members are GSA representatives plus a representative from CCWD that meet monthly to coordinate GSP development. Figure 1-2 provides the management structure. In September 2018, the ECC GSP Working Group applied for and received facilitation support services (FSS) from DWR. These services are provided by STANTEC through January of 2022. FSS provides assistance from professional facilitators to encourage active involvement of diverse social, cultural, and economic interests and consider all beneficial uses and users of groundwater when developing and implementing GSPs. An ECC GSP Communication Committee was created to target public input required by GSP regulations. 10.2 List of Public Meetings Where the GSP was Discussed During the development of this GSP, public meetings were held and noticed on the ECC GSP website. Notifications were sent via email to the interested parties and via newspaper ads. Table 10-1 lists the public meetings where the GSP was discussed from June 2019 to August 2021. Opportunities for written comment were separately publicized and noticed, see below. Informational Public Meetings on ECC GSP Appendix 10a provides the complete list of outreach and communication for the ECC Subbasin and Table 10-1 provides a summary list of public information meetings and outreach on development of the the draft ECC Subbasin GSP. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 10 - NOTICE AND COMMUNICATION LSCE 10-4 Table 10-1. List of Public Information Meetings and Outreach on the Draft ECC Subbasin GSP Format Date Detail Participation Purpose Public Meetings July 9, 2020 June 23, 2021 September 14, 2021 Online/Virtual Online/Virtual (recorded) Online/Virtual 33 47 ?? 1. Review SGMA and Sections 1&2 2. Review Secs 3-9 3. Review entire GSP Postcard Mailings September 2018 August 2021 Postcard to public water systems and local agencies 120 of 153 1. Basin Boundary Modification Support & SGMA 2. GSP public comment period Surveys on ECC GSP Website Dec. 7, 2018 May 2020 to Oct0ber 2021 On-line survey for individual GSP Sections and entire GSP Outreach Assessment =21 Chapter comments =28 Learn about GSPs Provided for public comment Email Listserv 300 emails were mailed to interested parties prior to each public meeting Notifications to interested parties list 900 emails Notification of Sections available for review and comment and for public meeting announcements. Public Board Meetings January 2015 to August 2021 36 GSA public Board meetings ECC GSP updates ECC GSP Working Group Meetings June 2017 to August 2021 Total of 45 monthly meetings Varied Plan GSP Development ECC GSP Communications Committee Meetings 2019 to 2021 Total of 15 separate meetings varied Plan public outreach Website August 2019 to present https://www.eccc- irwm.org/about- sgma 2019:205 views 2020: 506 views 2021: 620 views (to 8/3/21) Update on GSP Development Monthly Newsletter September 2020 to January 2022 1 page pdf posted on ECC GSP Website and distributed to GSAs To GSAs and posted on Website Update on GSP Development Public Meeting Notice Prior to each public workshop Newspaper advertising Circulation to approximately 210,000 homes Public Notice EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 10 - NOTICE AND COMMUNICATION LSCE 10-5 Outreach Presentations to Community Groups Municipal Advisory Councils (MAC) in the unincorporated County within the ECC groundwater basin are the Bethel Island Municipal Improvement District, the Byron Municipal Advisory Council, and the Knightsen Town Advisory Council. Each MAC meets regularly to advise the County of Board of Supervisors on discretionary land use projects, among other things. The County GSA emailed the draft GSP to individual members of each MAC above and presented the draft GSP on the following dates: • Knightsen Town Advisory Council-September 14, 2021 • Byron Municipal Advisory Council-September 28, 2021 • Bethel Island Municipal Improvement District-October 12, 2021 10.3 Comments on the GSP and a Summary of Responses Appendix 10b provides the comments on the GSP and a summary of responses. 10.4 Decision-Making Process On May 9, 2017, the ECC GSAs and CCWD entered into a Memorandum of Understanding (MOU) for the development of a single GSP for the ECC Subbasin and agreed to collaborate to ensure sustainable groundwater management for the subbasin, manage the groundwater subbasin as efficiently as practicable balancing the financial resources of the agencies with the principles of effective and safe groundwater management, while retaining groundwater management authority within their respective jurisdictions. Minor amendments were approved in the MOU on November 16, 2017, and April 13, 2020. By agreement of the GSAs and CCWD, the ECC GSP becomes effective when all parties adopt the GSP for the entire Subbasin. Under SGMA, each GSA Board is responsible to approve the GSP; the entire GSP will be submitted to DWR on or before January 31, 2022. The ECC Working Group directed the consultant Luhdorff & Scalmanini Consulting Engineers (LSCE) to fulfill the requirements of SGMA. LSCE provided the Working Group with draft GSP Sections, budgets, and other work products as required to complete the GSP. As described in detail below, public involvement of all beneficial users was sought from the start, and their input and feedback are included in the decision-making process for the GSP. 10.5 Opportunities for Public Engagement and How Public Input and Response was Used The ECC stakeholders and the public were notified and encouraged to participate in the development of the GSP as outlined in the ECC Subbasin Communications Plan (Appendix 10c). The DWR FSS Program provided assistance to complete this task. Actions to engage the public are identified below, and Table 10-1 provides a summary of public engagement opportunities. ECC GSP Website: The ECC GSP website at https://www.eccc-irwm.org/about-sgma has been active since August 2019 and is continually maintained with current and updated documents that comprise the parts of the GSP. Contact information is presented for stakeholders to communicate with the ECC GSAs and the public can be added to the ECC GSP mailing list to receive updates on upcoming events. Meeting information with agendas and summary notes are posted regularly along with technical reports and educational materials. During GSP implementation the website will continue to be active and provide quarterly updates. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 10 - NOTICE AND COMMUNICATION LSCE 10-6 East County Times and the Brentwood Press: ECC GSP Monthly Newsletter: Provides monthly updates on the progress of the GSP, posted to the ECC GSP website. GSA Board Meetings: ECC GSAs Board meetings where the ECC GSP was discussed presented information to the respective GSA Boards and the public. Public Workshops: Informational meetings to provide the public with SGMA information and the GSP process (Table 10-1). Public Outreach on Draft ECC Sections: Draft sections of the GSP were posted for public comment as they became available (see Table 10-2 below) along with two public meetings with Q&A sessions (July 2020 and June 2021). The surveys for each section were “live” and available for public comment through August 2021. Table 10-2. Public Comment Period for each GSP Section GSP Section Public Comment Period 1. Introduction to East Contra Costa GSP April to July 2020 2. Plan Area 3. Basin Setting 10/30/2020 to 1/15/2021 4. Historical, Current, and Projected Water Supply 11/2020 to 1/15/2021 5. Water Budget Aug 9 to Aug 23 2021 6. Monitoring Network, Data Management System and Reporting 4/8/2021 to 5/3/2021 7. Sustainable Management Criteria (SMC) 7/16 to 8/16/2021 8. Projects and Management Actions (PMA) 9. Plan Implementation 10. Notice and Communications Public Outreach on the Entire Draft ECC Subbasin GSP: The complete draft ECC Subbasin GSP was available for the month of September 2021 for public comment, this included one public meeting with Q&A in September 2021. Postcard Mailers: Two postcard mailers to about 94 interested parties (public water systems and local agencies) to engage this group (2018) about the basin boundary modification and SGMA. Surveys: Each Draft Section of the ECC Subbasin GSP when posted to the ECC GSP website included a survey for interested parties to express their needs and concerns. 29 people responded. Existing Outreach: GSAs use existing outreach networks to provide regular updates about the GSP development. This includes information through bill inserts, newsletters, and presentations to their boards. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 SECTION 10 - NOTICE AND COMMUNICATION LSCE 10-7 10.6 Encouraging Active Involvement As discussed in Sections 10.2 and 10.5, the outreach and education process are important to develop a comprehensive GSP, and the ECC Working Group has prioritized involvement by interested parties in the GSP effort. The following strategies were developed to encourage stakeholder engagement: • Conduct a comprehensive outreach and education process that facilitates development of a GSP that meets SGMA requirements. • Keep the stakeholders informed by providing timely and accurate information. • Provide opportunities for interested parties to provide input during the planning process. • Provide opportunities for input during every step of the GSP process. • Update the outreach process throughout the GSP process as needed. • Multiple opportunities were provided for stakeholders to review and comment on each of the sections as they were being developed (Table 10-2). 10.7 Informing the Public on GSP Implementation Progress The draft GSP was posted to the ECC GSP website on September 1, 2021 and was available for a 30-day public review and comment period. A public meeting was held on September 14, 2021 to provide an overview of the GSP content and an opportunity for stakeholder feedback and comments about the GSP. These comments will be taken into consideration and incorporated into a final version of the GSP that will be adopted by each of the seven GSA Board of Directors before submitting to DWR by the deadline of January 31, 2022. Stakeholders will be given an additional 60-day comment period through DWR’s SGMA portal at https://sgma.water.ca.gov/portal/gsp/status following the submittal. Comments will be posted to DWR’s website prior to the evaluation and approval by DWR. The ECC GSP Working Group will continue to meet to guide the GSP implementation process through ongoing monitoring and sustainable groundwater management. The adopted Communication and Engagement Plan will guide future outreach during the GSP implementation process. 10.8 Interbasin Coordination A list of interbasin coordination meetings with neighboring subbasins is below: • Tracy Subbasin-February 12, 2020, and September 30, 2020 • Solano Subbasin (LSCE technical consultant for both ECC and Solano Subbasins) • Eastern San Joaquin Subbasin Appendix 1a- Definitions and Key Terms Appendix 1b- Amended and Restated Memorandum of Understanding, Development of a Groundwater Sustainability Plan for the East Contra Costa Subbasin Appendix 3a- Investigation of Ground-water Resources in East Contra Costa Area, 1999 Appendix 3b- An Evaluation of Geological Conditions, East Contra Costa County, 2016 Appendix 3c- Well Construction Table-East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR Wells Appendix 3d- Groundwater Level Hydrographs Appendix 3e- Historical Groundwater Elevation Contour Maps Appendix 3f- Summary of Groundwater Quality Laboratory Results Appendix 3g- Groundwater Quality Graphs (TDS, EC, Cl, NO3, As) Appendix 3h- Groundwater Contamination Sites Appendix 3i- ECC Subbasin Oil and Gas Wells and Fields Appendix 4a- Individual Surface Water Diversions: Point of Delivery Totals by Tract/Model Subregion and by Calendar Year Appendix 5a- East Contra Costa Groundwater Surface Water Simulation Model Report Appendix 6a- Monitoring Protocols Appendix 7a- Representative Monitoring Sites Minimum Thresholds, Measurable Objectives for Chronic Lowering of Groundwater Levels APPENDICES Appendix 7b- Comparison of Domestic Wells and Depth to Minimum Threshold Appendix 9a- East Contra Costa Groundwater Sustainability Plan Implementation Budget Appendix 10a- Summary List of Public Meetings and Outreach Appendix 10b- ECC GSP Summary of Public Comments on the Draft ECC GSP and Responses Appendix 10c- East Contra Costa Subbasin Communications Plan Definitions and Key Terms (CWC 10721 and 23 CCR 351) APPENDIX 1a EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TERMS AND DEFINITIONS LSCE 1 TERMS AND DEFINITIONS “Working Group” refers to representatives of seven GSAs in the East Contra Costa Subbasin (City of Antioch, City of Brentwood, Byron-Bethany Irrigation District, Contra Costa County, Diablo Water District, Discovery Bay Community Services District, and East Contra Costa Irrigation District) plus a representative from Contra Costa Water District (an equal partner and financial contributor) that meet monthly to coordinate GSP development. Cited from: Section 10733.2, Water Code “Agency” refers to a groundwater sustainability agency as defined in the Act. “Agricultural water management plan” refers to a plan adopted pursuant to the Agricultural Water Management Planning Act as described in Part 2.8 of Division 6 of the Water Code, commencing with Section 10800 et seq. “Alternative” refers to an alternative to a Plan described in Water Code Section 10733.6. “Annual report” refers to the report required by Water Code Section 10728. “Baseline” or “baseline conditions” refer to historic information used to project future conditions for hydrology, water demand, and availability of surface water and to evaluate potential sustainable management practices of a basin. “Basin” means a groundwater basin or subbasin identified and defined in Bulletin 118 or as modified pursuant to Water Code 10722 et seq. “Basin setting” refers to the information about the physical setting, characteristics, and current conditions of the basin as described by the Agency in the hydrogeologic conceptual model, the groundwater conditions, and the water budget, pursuant to Subarticle 2 of Article 5. “Best available science” refers to the use of sufficient and credible information and data, specific to the decision being made and the time frame available for making that decision, that is consistent with scientific and engineering professional standards of practice. “Best management practice” refers to a practice, or combination of practices, that are designed to achieve sustainable groundwater management and have been determined to be technologically and economically effective, practicable, and based on best available science. “Board” refers to the State Water Resources Control Board. “CASGEM” refers to the California Statewide Groundwater Elevation Monitoring Program developed by the Department pursuant to Water Code Section 10920 et seq., or as amended. “Data gap” refers to a lack of information that significantly affects the understanding of the basin setting or evaluation of the efficacy of Plan implementation and could limit the ability to assess whether a basin is being sustainably managed. “Groundwater dependent ecosystem” refers to ecological communities or species that depend on groundwater emerging from aquifers or on groundwater occurring near the ground surface. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TERMS AND DEFINITIONS LSCE 2 “Groundwater flow” refers to the volume and direction of groundwater movement into, out of, or throughout a basin. “Interconnected surface water” refers to surface water that is hydraulically connected at any point by a continuous saturated zone to the underlying aquifer and the overlying surface water is not completely depleted. “Interested parties” refers to persons and entities on the list of interested persons established by the Agency pursuant to Water Code Section 10723.4. “Interim milestone” refers to a target value representing measurable groundwater conditions, in increments of five years, set by an Agency as part of a Plan. “Management area” refers to an area within a basin for which the Plan may identify different minimum thresholds, measurable objectives, monitoring, or projects and management actions based on differences in water use sector, water source type, geology, aquifer characteristics, or other factors. “Measurable objectives” refer to specific, quantifiable goals for the maintenance or improvement of specified groundwater conditions that have been included in an adopted Plan to achieve the sustainability goal for the basin. “Minimum threshold” refers to a numeric value for each sustainability indicator used to define undesirable results. “NAD83” refers to the North American Datum of 1983 computed by the National Geodetic Survey, or as modified. “NAVD88” refers to the North American Vertical Datum of 1988 computed by the National Geodetic Survey, or as modified. “Plain language” means language that the intended audience can readily understand and use because that language is concise, well-organized, uses simple vocabulary, avoids excessive acronyms and technical language, and follows other best practices of plain language writing. “Plan” refers to a groundwater sustainability plan as defined in the Act. “Plan implementation” refers to an Agency’s exercise of the powers and authorities described in the Act, which commences after an Agency adopts and submits a Plan or Alternative to the Department and begins exercising such powers and authorities. “Plan manager” is an employee or authorized representative of an Agency, or Agencies, appointed through a coordination agreement or other agreement, who has been delegated management authority for submitting the Plan and serving as the point of contact between the Agency and the Department. “Principal aquifers” refer to aquifers or aquifer systems that store, transmit, and yield significant or economic quantities of groundwater to wells, springs, or surface water systems. “Reference point” refers to a permanent, stationary and readily identifiable mark or point on a well, such as the top of casing, from which groundwater level measurements are taken, or other monitoring site. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TERMS AND DEFINITIONS LSCE 3 “Representative monitoring” refers to a monitoring site within a broader network of sites that typifies one or more conditions within the basin or an area of the basin. “Seasonal high” refers to the highest annual static groundwater elevation that is typically measured in the Spring and associated with stable aquifer conditions following a period of lowest annual groundwater demand. “Seasonal low” refers to the lowest annual static groundwater elevation that is typically measured in the Summer or Fall, and associated with a period of stable aquifer conditions following a period of highest annual groundwater demand. “Seawater intrusion” refers to the advancement of seawater into a groundwater supply that results in degradation of water quality in the basin, and includes seawater from any source. “Statutory deadline” refers to the date by which an Agency must be managing a basin pursuant to an adopted Plan, as described in Water Code Sections 10720.7 or 10722.4. “Sustainability indicator” refers to any of the effects caused by groundwater conditions occurring throughout the basin that, when significant and unreasonable, cause undesirable results, as described in Water Code Section 10721(x). “Uncertainty” refers to a lack of understanding of the basin setting that significantly affects an Agency’s ability to develop sustainable management criteria and appropriate projects and management actions in a Plan, or to evaluate the efficacy of Plan implementation, and therefore may limit the ability to assess whether a basin is being sustainably managed. “Urban water management plan” refers to a plan adopted pursuant to the Urban Water Management Planning Act as described in Part 2.6 of Division 6 of the Water Code, commencing with Section 10610 et seq. “Water source type” represents the source from which water is derived to meet the applied beneficial uses, including groundwater, recycled water, reused water, and surface water sources identified as Central Valley Project, the State Water Project, the Colorado River Project, local supplies, and local imported supplies. “Water use sector” refers to categories of water demand based on the general land uses to which the water is applied, including urban, industrial, agricultural, managed wetlands, managed recharge, and native vegetation. “Water year” refers to the period from October 1 through the following September 30, inclusive, as defined in the Act. “Water year type” refers to the classification provided by the Department to assess the amount of annual precipitation in a basin. Cited from: PART 2.74. Sustainable Groundwater Management [10720 - 10737.8] - CHAPTER 2. Definitions [10721- 10721.] “Adjudication action” means an action filed in the superior or federal district court to determine the rights to extract groundwater from a basin or store water within a basin, including, but not limited to, actions to EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TERMS AND DEFINITIONS LSCE 4 quiet title respecting rights to extract or store groundwater or an action brought to impose a physical solution on a basin. “Basin” means a groundwater basin or subbasin identified and defined in Bulletin 118 or as modified pursuant to Chapter 3 (commencing with Section 10722). “Bulletin 118” means the department’s report entitled “California’s Groundwater: Bulletin 118” updated in 2003, as it may be subsequently updated or revised in accordance with Section 12924. “Coordination agreement” means a legal agreement adopted between two or more groundwater sustainability agencies that provides the basis for coordinating multiple agencies or groundwater sustainability plans within a basin pursuant to this part. “De minimis extractor” means a person who extracts, for domestic purposes, two acre-feet or less per year. “Governing body” means the legislative body of a groundwater sustainability agency. “Groundwater” means water beneath the surface of the earth within the zone below the water table in which the soil is completely saturated with water, but does not include water that flows in known and definite channels unless included pursuant to Section 10722.5. “Groundwater extraction facility” means a device or method for extracting groundwater from within a basin. “Groundwater recharge” or “recharge” means the augmentation of groundwater, by natural or artificial means. “Groundwater sustainability agency” means one or more local agencies that implement the provisions of this part. For purposes of imposing fees pursuant to Chapter 8 (commencing with Section 10730) or taking action to enforce a groundwater sustainability plan, “groundwater sustainability agency” also means each local agency comprising the groundwater sustainability agency if the plan authorizes separate agency action. “Groundwater sustainability plan” or “plan” means a plan of a groundwater sustainability agency proposed or adopted pursuant to this part. “Groundwater sustainability program” means a coordinated and ongoing activity undertaken to benefit a basin, pursuant to a groundwater sustainability plan. “In-lieu use” means the use of surface water by persons that could otherwise extract groundwater in order to leave groundwater in the basin. “Local agency” means a local public agency that has water supply, water management, or land use responsibilities within a groundwater basin. “Operator” means a person operating a groundwater extraction facility. The owner of a groundwater extraction facility shall be conclusively presumed to be the operator unless a satisfactory showing is made to the governing Home Bill Information California Law Publications Other Resources My Subscriptions My Favorites body of the groundwater sustainability agency that the groundwater extraction facility actually is operated by some other person. “Owner” means a person owning a groundwater extraction facility or an interest in a groundwater extraction facility other than a lien to secure the payment of a debt or other obligation. EAST CONTRA COSTA SUBBASIN GSP OCTOBER 2021 TERMS AND DEFINITIONS LSCE 5 “Personal information” has the same meaning as defined in Section 1798.3 of the Civil Code. “Planning and implementation horizon” means a 50-year time period over which a groundwater sustainability agency determines that plans and measures will be implemented in a basin to ensure that the basin is operated within its sustainable yield. “Public water system” has the same meaning as defined in Section 116275 of the Health and Safety Code. “Recharge area” means the area that supplies water to an aquifer in a groundwater basin. “Sustainability goal” means the existence and implementation of one or more groundwater sustainability plans that achieve sustainable groundwater management by identifying and causing the implementation of measures targeted to ensure that the applicable basin is operated within its sustainable yield. “Sustainable groundwater management” means the management and use of groundwater in a manner that can be maintained during the planning and implementation horizon without causing undesirable results. “Sustainable yield” means the maximum quantity of water, calculated over a base period representative of long-term conditions in the basin and including any temporary surplus, that can be withdrawn annually from a groundwater supply without causing an undesirable result. “Undesirable result” means one or more of the following effects caused by groundwater conditions occurring throughout the basin: (1) Chronic lowering of groundwater levels indicating a significant and unreasonable depletion of supply if continued over the planning and implementation horizon. Overdraft during a period of drought is not sufficient to establish a chronic lowering of groundwater levels if extractions and groundwater recharge are managed as necessary to ensure that reductions in groundwater levels or storage during a period of drought are offset by increases in groundwater levels or storage during other periods. (2) Significant and unreasonable reduction of groundwater storage. (3) Significant and unreasonable seawater intrusion. (4) Significant and unreasonable degraded water quality, including the migration of contaminant plumes that impair water supplies. (5) Significant and unreasonable land subsidence that substantially interferes with surface land uses. (6) Depletions of interconnected surface water that have significant and unreasonable adverse impacts on beneficial uses of the surface water. “Water budget” means an accounting of the total groundwater and surface water entering and leaving a basin including the changes in the amount of water stored. “Watermaster” means a watermaster appointed by a court or pursuant to other law. “Water year” means the period from October 1 through the following September 30, inclusive. “Wellhead protection area” means the surface and subsurface area surrounding a water well or well field that supplies a public water system through which contaminants are reasonably likely to migrate toward the water well or well field. Amended and Restated Memorandum of Understanding, Development of a Groundwater Sustainability Plan for the East Contra Costa Subbasin APPENDIX 1b Page 1 of 19 AMENDED AND RESTATED 1 MEMORANDUM OF UNDERSTANDING 2 3 Development of a Groundwater Sustainability Plan 4 for the East Contra Costa Subbasin, (DWR Basin 5-22.19, San Joaquin Valley) 5 6 This Amended and Restated Memorandum of Understanding for the Development of a 7 Groundwater Sustainability Plan for the East Contra Costa Subbasin, (DWR Basin 5-22.19, San 8 Joaquin Valley) (“MOU”) is entered into and effective this 13th day of April, 9 2020 (“Effective Date”) by and among the City of Antioch (“Antioch”), City of Brentwood 10 (“Brentwood”), Byron-Bethany Irrigation District (“BBID”), Contra Costa Water District 11 (“CCWD”), Contra Costa County (“County”), Diablo Water District (“DWD”), East Contra 12 Costa Irrigation District (“ECCID”), and Discovery Bay Community Services District 13 (“Discovery Bay”). Each of the foregoing parties to this MOU is sometimes referred to herein as 14 a “Party” and are collectively sometimes referred to as the “Parties.” 15 Recitals 16 A. In September 2014, the California Legislature enacted the Sustainable Groundwater17 Management Act of 2014 (“SGMA”), which established a statewide framework for the sustainable 18 management of groundwater resources. That framework focuses on granting new authorities and 19 responsibility to local agencies while holding those agencies accountable. The framework also 20 provides for state intervention where a local agency fails to develop a groundwater sustainability 21 plan in a timely manner. 22 Page 2 of 19 B. The East Contra Costa Subbasin (“Basin”) is referred to as DWR Basin 5-22.19, 23 San Joaquin Valley, and is shown on the map attached hereto as Exhibit A and incorporated herein 24 by reference as if set forth in full. The Basin is located in eastern Contra Costa County. The 25 Parties collectively overlie all of the Basin. 26 C. Under SGMA, one or more local agencies may form a groundwater sustainability 27 agency (“GSA”), by memorandum of agreement, joint exercise of powers agreement, or other 28 agreement. (Wat. Code, §§ 10723(a), 10723.6.) The Parties desire for each Party to be the GSA 29 within all or a portion of that Party’s boundary. The Parties further desire to develop a governance 30 structure for the Basin to be considered during development of the groundwater sustainability plan 31 (a “GSP”) for the Basin (the “Basin GSP”). The Parties further desire to resolve areas of 32 jurisdictional overlap so that no two Parties serve as GSAs over the same area. The purpose of 33 this MOU is to coordinate the Parties’ activities related to each Party becoming a GSA, 34 development of the Basin GSP, and each Party’s future consideration of whether to adopt the Basin 35 GSP. 36 D. The Parties wish to collaborate in an effort to ensure sustainable groundwater 37 management for the Basin, manage the groundwater basin as efficiently as practicable balancing 38 the financial resources of the agencies with the principles of effective and safe groundwater 39 management, while retaining groundwater management authority within their respective 40 jurisdictions. The Parties desire to share responsibility for Basin management under SGMA. The 41 Parties recognize that the key to success in this effort will be the coordination of activities under 42 SGMA, and the collaborative development of the Basin GSP, which each Party may consider 43 adopting and implementing within its GSA management area. 44 Page 3 of 19 E. The Basin has been designated by the California Department of Water Resources 45 (“DWR”) as a medium-priority groundwater basin, which, under the terms of SGMA, means that 46 the Parties must submit a Basin GSP to DWR by January 31, 2022. 47 F. This MOU amends and restates the original Memorandum of Understanding, dated 48 May 9, 2017, and as amended on November 16, 2017. This MOU also recognizes changes that 49 reflect DWR’s determination that, for purposes of SGMA, the Basin is separate and distinct from 50 other portions of the Tracy Subbasin located in San Joaquin and Alameda Counties. The Basin is 51 located entirely within Contra Costa County. The Parties wish to memorialize and restate their 52 commitments by means of this MOU. 53 Understandings 54 1. Term. The term of this MOU begins on the Effective Date, which shall occur upon 55 execution of this MOU by all eight of the parties, and this MOU shall remain in full force 56 and effect until the earliest of the following events: (i) January 31, 2022, (ii) the date upon 57 which the Parties submit a Basin GSP to DWR, or (iii) the date upon which the Parties then 58 party to the MOU execute a document jointly terminating the provisions of this MOU. An 59 individual Party’s obligations under this MOU terminate when the Party withdraws from 60 the MOU in accordance with Section 4. 61 2. Development of the GSP 62 a. Parties to Become GSAs. Each Party, except Contra Costa Water District, agrees 63 to take the necessary actions to become the GSA for all or a portion of that area of 64 the East CC Basin that it overlies, as shown on Exhibit A, attached hereto, no later 65 than April 1, 2017, or shortly thereafter. The Parties shall jointly submit the Parties’ 66 Page 4 of 19 individual elections to become GSAs and this MOU to DWR prior to April 1, 2017, 67 or shortly thereafter. The Parties further agree to develop a governance structure 68 for the Basin to be considered during development of the Basin GSP 69 b. Single GSP. The Parties will collaborate to develop a single Basin GSP that, at a 70 minimum, satisfies the GSP requirements in the SGMA and the regulations 71 promulgated under the SGMA. The Basin GSP must include an analysis of 72 implementation costs and revenue sources, and must include an analysis of 73 governance structure options. The Basin GSP shall be drafted in a manner that 74 preserves, and does not purport to supersede, the land use authority of each city or 75 county, or the statutory authority of each special district, that is a party to this MOU. 76 The Basin GSP must include provisions for consultation between a GSA and any 77 public agency that the GSA overlaps before the GSA takes any action that may 78 relate to that public agency’s exercise of its statutory authority. Unless the Parties 79 later agree otherwise, it is intended that the Basin GSP will be implemented by 80 each Party within its respective GSA management area, and that the Parties will 81 coordinate their implementation of the Basin GSP. 82 c. Overlap Areas. Solely for the purpose of complying with the SGMA requirement 83 that GSA management areas not overlap, the Parties agree that there are no 84 overlapping GSA management areas, as shown on Exhibit A. This MOU does not 85 purport to limit any Party’s legal authority to utilize and deliver groundwater or 86 surface water throughout its jurisdictional boundary (as may be amended from 87 time-to-time), which may include area outside of a Party’s management area shown 88 on Exhibit A. 89 Page 5 of 19 d. Cooperation of Efforts. The Parties will designate staff who will endeavor to meet 90 monthly or more frequently if necessary to develop the terms of the Basin GSP in 91 an expeditious manner. 92 e. Contracting with Consultant & Cost Share Among the Parties. 93 (1) Contracting with Consultant. 94 A. Contract for the Preparation of the GSP. Brentwood, acting on 95 behalf of the other Parties, shall promptly enter into an agreement with Luhdorff and Scalmanini 96 (“Consultant”) for the preparation of the Basin GSP. 97 98 B. Annual Budgets and Scopes of Work. Not later than each 99 February 15, Brentwood shall obtain a proposed budget and scope from Consultant for services 100 during the upcoming fiscal year. Brentwood shall promptly provide the proposed budget and 101 scope to the other Parties and shall give the other Parties until each March 15 to review the 102 proposed budget and scope, and provide written comments to Brentwood. Such comments shall 103 include each Party’s determination as to whether it is willing to pay its share of the cost of such 104 work, as identified in Paragraph 2(e)(2). If, after each March 15, no Party has indicated in 105 writing that it is unwilling to pay its share of the cost of such work, the Consultant’s budget and 106 scope for the upcoming fiscal year shall be deemed approved and Brentwood shall take such 107 actions as may be necessary to cause Consultant to perform the services included in that budget 108 and scope of work. In the event that one or more Parties object to the proposed budget and scope 109 of work, the Parties shall promptly meet and confer to determine an appropriate course of action. 110 C. Payments by Parties to Brentwood. Brentwood shall, upon receipt 111 of Consultant’s monthly invoices, pay Consultant for services rendered during the previous 112 Page 6 of 19 month. Brentwood will promptly provide invoices to the other Parties identifying their shares of 113 the cost of the previous month’s work and such other Parties shall pay said invoices within 45 114 days of receipt. 115 (2) Cost-Share for Basin GSP. The costs associated with developing the 116 Basin GSP (“GSP Costs”), including but not limited to, any local cost-shares required by state or 117 federal grants, will be shared equally among the Parties. 118 119 A. In-Kind Services Provided by County. The County, at its sole 120 discretion, may satisfy its share of GSP Costs by providing in-kind services, which may include 121 but may not be limited to mapping, graphics, and database management services. The County 122 will provide written notice to the other Parties by the March 15 immediately preceding the fiscal 123 year stating either that the County will pay its share of GSP Costs in the fiscal year, or that the 124 County will provide in-kind services in lieu of paying its share of GSP Costs in the fiscal year. 125 In the case of payments to Consultant or other vendors where the County wishes to substitute in-126 kind services for direct payments, Brentwood shall allocate such invoices equally among the 127 Parties other than the County. Notwithstanding anything to the contrary contained herein, no 128 Party shall be obligated to pay the County for the value of any in-kind services provided by the 129 County, and the value of any in-kind services provided by the County shall only act as a credit 130 towards the County’s share of GSP Costs, as more particularly described in 2(e)(2)(B). 131 B. Annual Accounting. Brentwood shall prepare an annual 132 accounting by October 1 that shows all GSP Costs for the previous fiscal year and that identifies 133 in-kind services provided by the County and the County’s calculation of the value of those in-134 kind services. By July 30th following the end of a fiscal year, the County will provide 135 Page 7 of 19 Brentwood an accounting of the County’s in-kind services during the prior fiscal year, and any 136 carry-over value of in-kind services provided during any fiscal years preceding the prior fiscal 137 year. The value of the County’s in-kind services will be calculated based on (1) the then-current 138 fully-burdened hourly rates for County staff time, benefits, and overhead, and (2) the County’s 139 actual costs for any materials or supplies required to provide the in-kind services. 140 i. Upon written notice to the other Parties no later than 15 141 days after receiving Brentwood’s annual accounting, any Party other than the County may 142 dispute the County’s calculation of the value of the in-kind services that the County provided 143 during the fiscal year for which the accounting is prepared, but no Party may challenge the value 144 of in-kind services that were carried over from any fiscal year preceding the fiscal year for which 145 the accounting is prepared. In the event that one or more Parties provide notice of a dispute 146 under this subparagraph, the Parties shall promptly meet and confer in an effort to resolve the 147 dispute to the satisfaction of all Parties. The County’s obligation to make any payments to other 148 Parties under Paragraph 2(e)(2)(B)(ii) shall be tolled until the County receives, from each 149 disputing Party, written notice that the dispute has been resolved to the disputing Party’s 150 satisfaction. 151 ii. Except as expressly provided in Paragraph 2(e)(2)(B)(i), in 152 the event that Brentwood’s annual accounting shows that the value of the in-kind services 153 provided by the County during the fiscal year for which the accounting is prepared, plus any 154 carry-over value for in-kind services provided in any preceding fiscal years, is less than the 155 individual contributions of the other Parties during the fiscal year for which the annual 156 accounting is prepared, the County shall provide, by the November 30 following receipt of the 157 annual accounting, payments to each of the other Parties sufficient to equalize the values of the 158 Page 8 of 19 Parties’ contributions during the fiscal year for which the accounting is prepared. In the event 159 that Brentwood’s annual accounting shows that the value of the in-kind services provided by the 160 County during the fiscal year for which the accounting is prepared, plus any carry-over value for 161 in-kind services provided in any preceding fiscal years, is greater than the individual 162 contributions of the other Parties, Brentwood shall credit the County with the difference and 163 carry over that excess contribution to be credited towards the value of the County’s in-kind 164 services provided in the subsequent fiscal year. 165 f. Approval of the GSP. The Parties agree that the Basin GSP will become effective 166 for each Party when all of the Parties adopt the Basin GSP. 167 3. Savings Provisions. This MOU shall not operate to validate or invalidate, modify or affect 168 any Party’s water rights or any Party’s obligations under any agreement, contract or 169 memorandum of understanding/agreement entered into prior to the effective date of this 170 MOU. Nothing in this MOU shall operate to convey any new right to groundwater to any 171 Party. Each Party to this MOU reserves any and all claims and causes of action respecting 172 its water rights and/or any agreement, contract or memorandum of 173 understanding/agreement; any and all defenses against any water rights claims or claims 174 under any agreement, contract or memorandum of understanding/agreement. 175 4. Withdrawal. Any Party shall have the ability to withdraw from this MOU by providing 176 sixty (60) days written notice of its intention to withdraw. Said notice shall be given to 177 each of the other Parties. 178 a. A Party shall not be fiscally liable for expenditures following its withdrawal from 179 this MOU, provided that the Party provides written notice at least sixty (60) days 180 prior to the effective date of the withdrawal. A withdrawal shall not terminate, or 181 Page 9 of 19 relieve the withdrawing Party from, any express contractual obligation to another 182 Party to this MOU or to any third party incurred or encumbered prior to the 183 withdrawal. 184 b. In the event of a Party’s withdrawal, this MOU shall continue in full force and effect 185 among the remaining Parties. Further, a Party’s withdrawal from this MOU does 186 not, without further action by that Party, have any effect on the withdrawing Party’s 187 decision to be a GSA. A withdrawing Party shall coordinate the development of its 188 groundwater sustainability plan with the other Parties to this MOU. 189 5. CEQA. Nothing in this MOU commits any Party to undertake any future discretionary 190 actions referenced in this MOU, including but not limited to electing to become a GSA and 191 adopting the Basin GSP. Each Party, as a lead agency under the California Environmental 192 Quality Act (“CEQA”), shall be responsible for complying with all obligations under 193 CEQA that may apply to the Party’s future discretionary actions pursuant to this MOU, 194 including electing to become a GSA and adopting the Basin GSP. 195 6. Books and Records. Each Party shall have access to and the right to examine any of the 196 other Party’s pertinent books, documents, papers or other records (including, without 197 limitation, records contained on electronic media) relating to the performance of that 198 Party’s obligations pursuant to this Agreement, providing that nothing in this paragraph 199 shall be construed to operate as a waiver of any applicable privilege and provided further 200 that nothing in this paragraph shall be construed to give either Party rights to inspect the 201 other Party’s records in excess of the rights contained in the California Public Records Act. 202 7. General Provisions 203 Page 10 of 19 a. Authority. Each signatory of this MOU represents that s/he is authorized to execute 204 this MOU on behalf of the Party for which s/he signs. Each Party represents that it 205 has legal authority to enter into this MOU and to perform all obligations under this 206 MOU. 207 b. Amendment. This MOU may be amended or modified only by a written instrument 208 executed by each of the Parties to this MOU. 209 c. Jurisdiction and Venue. This MOU shall be governed by and construed in 210 accordance with the laws of the State of California, except for its conflicts of law 211 rules. Any suit, action, or proceeding brought under the scope of this MOU shall 212 be brought and maintained to the extent allowed by law in the County of Contra 213 Costa, California. 214 d. Headings. The paragraph headings used in this MOU are intended for convenience 215 only and shall not be used in interpreting this MOU or in determining any of the 216 rights or obligations of the Parties to this MOU. 217 e. Construction and Interpretation. This MOU has been arrived at through 218 negotiations and each Party has had a full and fair opportunity to revise the terms 219 of this MOU. As a result, the normal rule of construction that any ambiguities are 220 to be resolved against the drafting Party shall not apply in the construction or 221 interpretation of this MOU. 222 f. Entire Agreement. This MOU constitutes the entire agreement of the Parties with 223 respect to the subject matter of this MOU and supersedes any prior oral or written 224 Page 11 of 19 agreement, understanding, or representation relating to the subject matter of this 225 MOU. 226 g. Partial Invalidity. If, after the date of execution of this MOU, any provision of this 227 MOU is held to be illegal, invalid, or unenforceable under present or future laws 228 effective during the term of this MOU, such provision shall be fully severable. 229 However, in lieu thereof, there shall be added a provision as similar in terms to such 230 illegal, invalid or unenforceable provision as may be possible and be legal, valid 231 and enforceable. 232 h. Waivers. Waiver of any breach or default hereunder shall not constitute a 233 continuing waiver or a waiver of any subsequent breach either of the same or of 234 another provision of this MOU and forbearance to enforce one or more of the 235 remedies provided in this MOU shall not be deemed to be a waiver of that remedy. 236 i. Necessary Actions. Each Party agrees to execute and deliver additional documents 237 and instruments and to take any additional actions as may be reasonably required 238 to carry out the purposes of this MOU. 239 j. Compliance with Law. In performing their respective obligations under this MOU, 240 the Parties shall comply with and conform to all applicable laws, rules, regulations, 241 and ordinances. 242 k. Liability. Each Party agrees to indemnify and hold every other Party to the 243 Agreement, and their officers, agents and employees, free and harmless from any 244 costs or liability imposed upon any other Party, officers, agents, or employees 245 arising out of any acts or omissions of its own officers, agents or employees. 246 Page 12 of 19 l. Third Party Beneficiaries. This MOU shall not create any right or interest in any 247 non-Party or in any member of the public as a third party beneficiary. 248 m. Counterparts. This MOU may be executed in one or more counterparts, each of 249 which shall be deemed to be an original, but all of which together shall constitute 250 but one and the same instrument. 251 n. Notices. All notices, requests, demands or other communications required or 252 permitted under this MOU shall be in writing unless provided otherwise in this 253 MOU and shall be deemed to have been duly given and received on: (i) the date of 254 service if served personally or served by electronic mail or facsimile transmission 255 on the Party to whom notice is to be given at the address(es) provided below, (ii) 256 on the first day after mailing, if mailed by Federal Express, U.S. Express Mail, or 257 other similar overnight courier service, postage prepaid, and addressed as provided 258 below, or (iii) on the third day after mailing if mailed to the Party to whom notice 259 is to be given by first class mail, registered or certified, postage prepaid, addressed 260 as follows: 261 262 City of Antioch 263 City Manager 264 P.O. Box 5007 265 Antioch, CA 94531-5007 266 Telephone: (925) 779-7011 267 Facsimile: (925) 779-7003 268 269 Page 13 of 19 City of Brentwood 270 City Manager 271 150 City Park Way 272 Brentwood, CA 94513 273 Phone: (925) 516-5400 274 Fax: (925) 516-5441 275 276 Byron Bethany Irrigation District 277 General Manager 278 7995 Bruns Road 279 Byron, CA 94514-1625 280 Telephone: (209) 835-0375 281 Facsimile: (209) 835-2869 282 283 Contra Costa Water District 284 General Manager 285 Contra Costa Water District 286 P. O. Box H20 287 Concord, CA 94524 288 Phone (925) 688-8032 289 Fax (925) 688-8197 290 291 292 293 Page 14 of 19 Contra Costa County 294 Director, Department of Conservation and Development 295 30 Muir Road 296 Martinez, CA 94553 297 Phone (925) 674-7866 298 299 Diablo Water District 300 Attn: General Manager 301 P.O. Box 127 302 87 Carol Lane 303 Oakley, CA 94561 304 Phone: (925) 625-3798 305 Fax: (925) 625-0814 306 307 East Contra Costa Irrigation District 308 General Manager 309 1711 Sellers Avenue 310 Brentwood, CA 94513 311 Phone: (925) 634-3544 312 Fax: (925) 634-0897 313 314 315 316 317 Page 15 of 19 Discovery Bay Community Services District 318 C/O: General Manager 319 1800 Willow Lake Road 320 Discovery Bay, CA 94505-9376 321 Telephone: (925) 634-1131 322 Facsimile: (925) 513-2705 323 324 8. Signatures. The Following signatures attest each Party’s agreement hereto. 325 [Remainder of page left blank. Signatures on next pages.] 326 327 Page 16 of 19 CITY OF ANTIOCH 328 329 By: ______________________________________ Date: ____________________ 330 Rowland E. Bernal Jr., City Manager 331 APPROVED AS TO FORM: 332 333 By: ______________________________________ Date: ____________________ 334 Thomas Lloyd Smith, City Attorney 335 336 CITY OF BRENTWOOD 337 338 By: ______________________________________ Date: ____________________ 339 Tim Y. Ogden, City Manager 340 341 APPROVED AS TO FORM: 342 343 By: ______________________________________ Date: ____________________ 344 Damien Brower, City Attorney 345 346 BYRON BETHANY IRRIGATION DISTRICT 347 348 By: ______________________________________ Date:04/6/2020________________ 349 Rick Gilmore, General Manager 350 351 CONTRA COSTA WATER DISTRICT 352 353 By: ______________________________________ Date: ____________________ 354 Stephen J. Welch, General Manager 355 356 357 358 Page 17 of 19 APPROVED AS TO FORM: 359 360 By: ______________________________________ Date: ____________________ 361 District Legal Counsel 362 363 CONTRA COSTA COUNTY 364 365 By: ______________________________________ Date: ____________________ 366 John Kopchik, Director of 367 Conservation and Development 368 APPROVED AS TO FORM: 369 Sharon L. Anderson, County Counsel 370 371 By: ______________________________________ Date: ____________________ 372 Deputy County Counsel 373 374 DIABLO WATER DISTRICT 375 376 By: ______________________________________ Date: ____________________ 377 Dan Muelrath, General Manager 378 379 EAST CONTRA COSTA IRRIGATION DISTRICT 380 381 By: ______________________________________ Date: ____________________ 382 Aaron Trott, General Manager 383 384 APPROVED AS TO FORM: 385 386 By: ______________________________________ Date: ____________________ 387 District Legal Counsel 388 April 6, 2020 Page 19 of 19 EXHIBIT A 393 394 Investigation of Ground-water Resources in East Contra Costa Area, 1999 APPENDIX 3a Investigation of Ground-Water Resources in the East Contra Costa Area March 1999 Investigation of Ground-Water Resources in the East Contra Costa Area prepared by Luhdorff and Scalmanini Consulting Engineers Woodland, California March 1999 Thomas Elson Senior Engineer Kenneth Utley Senior Engineering Geologist Table of Contents Page I. Introduction ...................................................................1 Purpose...................................................................1 Scope ....................................................................1 Methods ..................................................................2 Findings ..................................................................3 II. Geology and Hydrogeology ......................................................5 Introduction ...............................................................5 Geologic Setting ...........................................................6 Hydrogeology .............................................................8 Depositional Model of Alluvium..............................................12 Depositional Model of Plio-Pleistocene Non-Marine Deposits ......................14 III. Ground-Water Conditions ......................................................17 Introduction ..............................................................16 Water Level Hydrographs ...................................................16 Water Level Contour Maps ..................................................18 Depth-to-Water Contour Maps ...............................................19 Ground-Water Quality ......................................................20 Aquifer Confinement.......................................................21 Recharge Sources..........................................................22 Basin Yield ..............................................................23 IV. Conclusions ................................................................25 Data Quantity and Quality ...................................................25 Hydrogeologic Regions .....................................................26 Ground-Water Conditions ...................................................26 Ground-Water Quality ......................................................27 Ground-Water Exploration and Development Potential ............................28 Recommendations .........................................................29 V. References ..................................................................31 Exhibits Base Map Well Map Cross Sections North-South Direction: A-C East-West Direction: 1-5 Hydrographs Hydrograph Well Location Map Hydrographs Ground-Water Contour Maps Spring and Fall: 1958, 1975, 1991 Spring: 1977 Fall: 1986, 1996 Depth-to-Water Contour Maps Spring and Fall: 1958, 1975, 1991 Spring: 1977 Fall: 1986, 1996 Water Quality Maps: Chloride; Nitrate; TDS Graphs: Nitrate; EC; Chloride; Alkalinity; pH; Sodium 1 I. Introduction Purpose An investigation was authorized by five east county public agencies in August 1998 to develop a greater understanding about ground-water resources in a portion of eastern Contra Costa County. The participating agencies were the Contra Costa County Water Agency, Contra Costa Sanitation District No. 19 (now Discovery Bay Community Services District), the City of Brentwood, Diablo Water District, and the East Contra Costa Irrigation District. The study area was generally defined as the region encompassing Brentwood and the East Contra Costa Irrigation District, extending to Byron to the south, Oakley to the north, and Discovery Bay to the east. The investigation focused on gathering existing information and organizing it in a manner in which it could be interpreted and analyzed to answer a set of basic questions concerning ground water. This report documents the results of the subject investigation. Besides the discussion of results contained in the text, the final work product of the investigation includes eight geologic cross sections depicting the distribution of aquifer units throughout the study area, hydrographs showing the fluctuations of ground-water levels over time, water level contour maps, and various graphs and maps of water quality constituents. All of these figures and graphs are included as exhibits to this report. Scope The scope of the investigation was posed as a set of basic questions about ground water within the study area: • What is the areal extent of the ground-water system in the study area? How is the aquifer system vertically divided and distributed? 2 • Is the ground-water system in the study area hydraulically connected to that in Discovery Bay to the east or Oakley to the north? • What are the characteristics of the ground-water system in terms of quantity and quality of water? • How is ground water recharged? How does ground water discharge, or flow out of the area? • Is the ground-water system overdrafted? • Can more ground water be developed? How much? Where? These questions represent significant issues facing public agencies throughout California with respect to managing existing resources and planning for future needs. In the east Contra Costa County study area, ground water has been used for various purposes for decades. However, no previous studies have addressed these questions to the extent that even a conceptual answer to the question concerning overdraft has been documented. In particular, there are no maps, cross sections, or descriptions of aquifer units containing ground water that have been historically targeted for domestic, municipal, or agricultural water supply purposes. In addition, there has been no basis for determining or predicting how incremental increases in ground-water pumping might affect the basin in the future. Finally, with regard to scope, this investigation was intended to address the questions cited above on a regional scale and assumed that, at least to some degree, the ground-water system would be found to be interconnected across boundaries of multiple water entities in the east county area. Methods The methods used in the investigation relied on existing information and data. This included material provided by various water entities within the study area, other information found through literature searches, and data obtained through the State Department of Water Resources and Division of Oil and Gas. The information sought for the investigation included anything related to ground water and consisted primarily of well data contained in drillers’ reports, i.e., descriptions of aquifer materials encountered while drilling wells. Other useful well data included measurements of 3 ground-water levels over time, results of ground-water quality tests, and well yields or production capacities. Multiple tools were used to depict ground-water conditions in the study area and included: Geologic Cross Sections - Cross sections were used to delineate and interpret the distribution and extent of aquifer materials throughout the study area. Aquifer materials were identified from drillers reports, geophysical surveys (electrical logs, or E-logs), as well as surveys conducted in oil and gas exploratory boreholes. Eight cross sections were constructed to correlate the occurrence of aquifer units throughout the study area and provide a depiction of horizontal and vertical distribution of these materials. Water Level Hydrographs - Hydrographs depicting water levels in wells over time were used to illustrate historical conditions in the ground-water system. Distinguishing trends were noted and used to interpret climatic influences versus possible impacts of pumping activities. Water Level Contour Maps - Water level contour maps were constructed to show the relative elevation of ground water throughout the study area. The maps illustrate the ground-water flow directions, and can be interpreted to define gradients for ground-water flow. Maps were constructed representing various points in time to interpret flow patterns on a seasonal basis, changes due to extremes in climatic conditions (e.g., drought periods), and changes due to influences of urbanization. Depth-to-Water Contour Maps - Depth-to-Water contour maps were constructed to show the proximity of ground water to the ground surface and to illustrate depth-to-water changes over time within the study area. Water Quality Maps and Graphs - Ground-water quality constituents were mapped and plotted in various forms to delineate and interpret distribution and trends in overall water quality. Findings In brief, the significant findings of the investigation include: 4 • There are four ground-water regions within the study area; those regions are distinguished by the manner in which aquifer materials were distributed and deposited. • Ground-water conditions in the western part of the study area (the vicinity of Brentwood) are distinct from the eastern region (the vicinity of Discovery Bay as well as northward to Oakley) as a result of depositional history. • For most of the study area, the extent of aquifer materials capable of yielding quantities of water suitable for municipal and/or agricultural purposes is to depths of 400 feet. • There is no apparent overdraft of the main ground-water system, suggesting that historical extraction patterns have not exceeded the safe yield of the basin with respect to ground-water levels and storage. • There have been no significant changes in the direction and rate of movement of ground- water within the study area since the late 1950's. • Data was found to be limiting for the purposes of defining patterns and factors influencing ground-water quality. However, total dissolved solids (TDS) and nitrate concentrations were found to be significant water quality factors throughout much of the study area. Discovery Bay is notable for relatively better water quality in terms of lower TDS and very low nitrate concentration. With respect to future needs, east county agencies with interests in ground-water resources would benefit from a program aimed at ongoing monitoring of ground-water conditions to avoid adverse impacts to the quantity and quality as a result of any future changes (e.g., increased pumpage) in historical use patterns. Such monitoring can be incrementally implemented with ongoing pumping plus any additions to pumpage which might be undertaken by one ore more of the local agencies. The following chapters discuss the basis for the findings cited above. In Chapter IV, Conclusions, specific recommendations are provided with regard to instituting a ground-water monitoring program which is considered especially important for management of ground-water resources in the east County area. 5 II. Geology and Hydrogeology Introduction This chapter presents the results of a detailed analysis and interpretation of subsurface conditions throughout the study area based primarily on information contained in well drillers’ reports. Three work products were produced in conjunction with this part of the ground-water investigation and are referred to below in the discussions of geologic setting and hydrogeology. The first work product is the project Base Map on which the study area is delineated through annotations of geologic and hydrogeologic features. The second is the project Well Map on which all the wells found and used to interpret the geologic setting are located. The third is a series of eight geologic cross sections which depict subsurface conditions throughout the study area. The location of the cross sections are delineated on the Base Map. The maps and cross sections appear at the end of this report. The discussion of the geologic setting is presented below to establish the background necessary to develop the subsequent description and interpretation of hydrogeology. Here, hydrogeology refers to how the geology of the study area is related to the occurrence of ground water. Ultimately, the interpretation of geologic setting and the hydrogeology of the study area is used to form distinct depositional models of four regions within the study area which are depicted on the Base Map. These regions are the Alluvial Plain (e.g., the greater Brentwood area), the Fluvial Plain (e.g., the area around Discovery Bay), the Delta Islands, and the Marginal Delta Dunes (e.g,. Oakley and vicinity). These regions have distinguishing subsurface characteristics which are derived from their geologic history. The depositional models are significant because they provide a basis for describing and predicting the occurrence and characteristics of ground water. Since this investigation is concerned with the beneficial use of ground water, i.e., as a water supply resource, the depositional models may be used to guide ground-water resource development and exploration. The cross sections are particularly suited for defining the horizontal and vertical extent and distribution of aquifer materials which might be targeted as ground-water supply sources. On a small scale, such models may prove useful 6 in explaining such matters of interest as variations in well yields, water quality, and mutual pumping interference. On a larger scale, the models can serve to describe regional patterns of recharge and ground-water flow direction. References pertaining to the discussion of the geologic setting are listed in Chapter V. It is notable that there were no useful references found regarding hydrogeology and the occurrence of ground water for the East Contra Costa study area. Thus, the material contained in this section and throughout this report is new and represents a basis for future studies and modeling, exploration efforts, water supply development, or any other activities which require some initial description of the hydrogeology of the project area. Geologic Setting The East Contra Costa County study area occurs on the western side of the northern San Joaquin Valley portion of the Great Valley province of California. West of the study area lies the lower foothills of the Diablo Mountains of the Coast Range province. At the north in the study area, the Sacramento and San Joaquin Rivers combine in the Delta and drain westward into the San Francisco Bay region. Surficial geology of the area is shown on the two regional geologic maps for the Sacramento and San Francisco-San Jose quadrangles (Wagner and others, 1981; Wagner and others, 1990). In the Coast Ranges, the geology consists of strongly deformed (faulted and folded) Mesozoic (pre-63 million years ago) marine sedimentary rocks of the Franciscan Complex and Great Valley Sequence. Along the northeastern edge of the Coast Range occur slightly less deformed, Tertiary (Eocene to Miocene, 55 to 5 million years) marine sedimentary rocks. The marine rocks of sandstones, shales, and mudstones trend northwest/southeast and dip, or slope, steeply to the north/northeast. These rocks are exposed in low hills from Deer Valley north to near Antioch, and southeast of Marsh Creek Reservoir. The Tertiary marine rocks extend east beneath the San Joaquin Valley with increasing depths to several thousand feet. These rocks contain saline water from their marine deposition and natural gas accumulations which are exploited in numerous gas fields in the area. Detailed surface geologic maps of the Coast Range in this area include Davis and Goldman (1958), Brabb and others (1971), and Dibblee (1980 a, b, c). Subsurface characterization of the marine rocks beneath the San Joaquin Valley are contained in oil and gas field summaries produced by the California Division of Oil & Gas (1982), and Theskenand and Adams (1995). General geologic 7 descriptions and histories of these marine rocks are contained in Bartow (1991), and Bertoldi and others (1991). Because of their marine origin, well consolidated nature, and saline water, the Mesozoic and Tertiary marine rocks are not a source of fresh ground water in the study area. Overlying the Tertiary marine rocks is a sequence of late Tertiary (Pliocene 5.3 to 1.6 million years) and Quaternary (Pleistocene 1.6 to 0.6 million years) non-marine sedimentary deposits. Surface exposures of these Plio-Pleistocene deposits are limited to an area south of Antioch to Oakley, and a small area south of Brentwood. These beds dip moderately to the east to northeast and extend eastward below the San Joaquin Valley. The nature of these Plio-Pleistocene deposits is poorly known in the study area. Subsurface information is limited to a few deep water well boreholes and oil and gas exploratory test holes. It is believed that these deposits occur below about 400 feet to depths of 1,500 to 2,000 feet below the San Joaquin River. Westward, the sequence thins and rises to near the surface overlying the Tertiary marine rocks of the Coast Range. These deposits seem to be dominated by fine-grained clays, silts, and mudstones with few sand beds. Water quality from electrical logs is difficult to interpret, but appears to become brackish with depth in the few sands encountered. Pleistocene to Holocene (600,000 years to present) alluvium overlies all of the older geologic units. These deposits are largely unconsolidated beds of gravel, sand, silts, and clays becoming weakly consolidated with increasing age and burial depth. These units were deposited by surface stream systems and contain fresh ground water and represent sources for extraction by water wells. Surface geologic mapping of the youngest units have used various names and subdivisions, largely based on soil characteristics (Welch, 1977), topographic position (Helley and others, 1979), and depositional environments (Atwater, 1982). In the subsurface, separation of the alluvium is difficult because of similar lithologic character and its poorly stratified nature. At best, correlation of sand and gravel beds of the alluvium is locally possible based on relative elevation and lateral extent and the use of water well drillers’ reports. The fine-grained silts and clay beds are generally so massive, thick, and homogenous that stratigraphic correlation is not possible. The alluvium thickens from a few tens of feet in the west to about 300 feet beneath Brentwood, and then generally thickens to about 400 feet beneath Old River. Sand and gravel beds tend to be thin and discontinuous in the west, and thin to pinch-out east of Brentwood. Beneath the river floor to the east, is a sequence of thicker more laterally extensive beds of sand and gravel deposited by the river within flood plain silts and clays. Description of the sand and gravel beds and their distribution in the study area are discussed in subsequent sections. 8 Hydrogeology Ground water studies or hydrogeologic studies in the area are relatively limited. Regional studies of the thickness of the Tertiary-Quaternary non-marine sedimentary deposits were made by Page (1974), and attempts were also made to evaluate the depth to base of fresh water by California State Water Project Authority (1956), and Berkstresser (1973). Regional studies of the Sacramento-San Joaquin Valley ground water basin include Bertoldi and others (1991), Page (1986), and Williamson and others (1989). The U.S. Geological Survey compiled water quality information which covers the area in a series of reports (Keeter 1980; Sorenson 1981; and Fogelman 1982). However, detailed hydrogeologic studies of east Contra Costa County examining aquifer nature and characteristics are virtually non-existent. Because of the lack of detailed hydrogeologic study of the subject East County area, a search of water well drillers’ reports on file at Department of Water Resources (DWR) was made. The area encompassed eastern Contra Costa County from about two miles west of Oakley, through the Delta Islands to just east of the county line, and extended south through Brentwood to about two miles south of Byron (see Base Map). Between 400 and 500 well logs were collected and the wells were located on topographic base maps based on each report's description. The wells were classified into depth zones of 100 foot intervals and are color coded on the Well Map. The vast majority of wells are less than 300 feet deep, with only a few wells (or boreholes) extending to greater depths. The wells also tend to be clustered in areas of suburban development where municipal water supply systems are not present. These areas are north of Brentwood towards Oakley, east of Oakley, and areas along the edges of the Delta Islands. Outside of these areas, well density is relatively low, generally only a few are located per square mile. The eastern area along the San Joaquin River flood plain has very low well density, with areas of few or no wells present. Outside of Byron, the southern area also has very low well density. Municipal supply wells are located in Brentwood, Oakley, Discovery Bay, and small service areas in the Delta. Agricultural/irrigation wells are scattered across the area. It is likely that many more domestic and some irrigation wells exist in the area, but do not have water well drillers’ reports on file with DWR. Lithologic descriptions on drillers’ reports are subjective, with the quality of the information provided in them dependent upon the experience, attention, and diligence of the multitude of drillers who have drilled in the region over the years. A more quantitative evaluation of subsurface 9 lithologies is possible from geophysical borehole surveys (electrical logs) run by professional well logging services. A search of DWR files, LSCE’s in-house files, and water agency files was also made for electrical logs. A few dozen electrical logs were found as a result of this effort, mostly in the Brentwood and Discovery Bay areas. The electrical logs provide the most precise delineation of aquifer units and for that purpose are considered a primary tool. Because of the lack of deep well control (over 500 feet) over most of the study area, a search of Division of Oil and Gas files was made to review electrical logs from the numerous oil and gas exploratory test holes in the area. About 200 oil and gas test hole files were reviewed. Many of these test holes were associated with the natural gas fields near Brentwood and north to the Delta. Scattered wildcat test holes (outside of the gas fields) were found across the study area with the lowest density in the southern portion of the study area. Most of the oil and gas electrical logs begin at depths of 800 to 1,000 feet, below the surface casing which is installed to protect fresh ground water in accordance with Division of Oil and Gas regulations. A few older test holes, pre-1960, extend to shallower depths, and in a few cases to the surface. The electrical logs were reviewed and notes made of depth of surface casing, lithologic character (clays and sands), and nature of water quality (saline, brackish, fresh). Most of the oil and gas electrical logs showed that the geologic material below 800 feet is dominated by fine-grained (clay and shale) deposits and some sandy zones with indications of saline or brackish water present. The base of fresh water was more difficult to determine, but seemed to correspond with published information. In general, the lack of suitable aquifers (sand and gravels) below 800 feet and their geophysical responses indicate that deep fresh water bearing aquifers do not exist in the area. One exception to this was found in a few oil and gas geophysical logs in the far northeast, outside the study area in San Joaquin County, where some fresh water aquifers in the 1,000 to 2,500 feet horizon were indicated. These may represent Tertiary non-marine deposits which were sourced from the Sierra Nevada. These deposits appear to pinch-out rapidly westward into finer-grained deposits and do not extend beneath the study area. A similar pattern has been seen in southern Sacramento County in the Elk Grove area. Geologic Cross Sections - In order to evaluate subsurface geologic conditions and relationships, a series of geologic cross sections was constructed as shown on the Base Map. Five cross sections were constructed in an east-west direction extending from the western foothills of the Coast Range out to the east Contra Costa County line (Cross Sections 1-5). Three additional cross sections were drawn in a north-south direction from the Delta to south of Byron (Cross Sections A-C). Because of the few wells extending to depths below 300 feet and areas of low well density, information from 10 electrical logs found at the Division of Oil and Gas was added to the cross sections to show the uppermost extent of deep well control. Review of these cross sections shows some general patterns in the occurrence and character of sand and gravel aquifers. Four regions having distinguishing characteristics were found and are delineated on the project Base Map. First, from about Lone Tree Road to south of Brentwood, extending about five miles east of the Coast Range foothills, exists the Alluvial Plain region consisting of eastward thickening deposits overlying Tertiary marine rocks. Most of the sand and gravel beds are located in the shallowest portion of these deposits. Near the foothills, the sand and gravel beds are about 100 feet or less in thickness, deepening to about 300 feet below Brentwood. These deposits are believed to be the Quaternary alluvium overlying the finer-grained Plio- Pleistocene non-marine deposits which extend to the base of fresh water or Tertiary marine rocks. The sand and gravel beds in the alluvium are largely thin bedded (less than 10 feet) and discontinuous laterally (Cross Sections 1, 2, 3, A, and B). Locally there are areas where several thin to thick sand beds exist in sequence (Cross Sections 1, 2, 3, and A). East of Brentwood, the number of sand and gravel beds appear to decrease, and bed thickness also decreases (Cross Sections 1, 2, and 3). This decrease in sand bed content can be seen by comparing Cross Sections A and B south of Cross Section 3. About one mile east of Brentwood, Cross Section B shows that most wells encounter mostly silt and clay with only a few thin, fine sand beds south of Cross Section 2. This pattern of low sand bed content extends south through Byron (see Cross Section B). A second region, Fluvial Plain, occurs to the east below the San Joaquin Valley floor. In this area, the sand and gravel beds appear to be thicker (20 to 30 feet) and more laterally extensive (Cross Sections 1, 2, and 3). These beds seem to correlate well in a north-south direction from Discovery Bay to Rock Slough (Cross Section C; north to about Cross Section 4). Westward, these beds seem to pinch out rapidly and disappear away from the river channels (Cross Sections 1, 2, and 3). The cross sections also show that below depths of 400 feet, a barren zone of few sand and gravel beds exist to at least 800 feet in depth (Cross Sections 1 and C). North of the Alluvial and Fluvial Plain regions occur two additional regions. The Delta Islands region swings in an arcurate westward direction (Cross Sections 4, 5, A, B, and C). In this area, more numerous thick, fine sand and gravel beds exist and appear to correlate moderately well. Details of the western end of this area beneath Jersey Island is limited by low well density (Cross Section A). Again, at depths below 400 feet, few sand beds are encountered to depths of at least 800 11 feet (Cross Sections B and C). Evidence of shallow saline or brackish water may be present in the shallow sand beds below the Delta Islands. The fourth region, Marginal Delta Dune, exists north of Lone Tree Road extending north to the edge of the Delta and westward beneath Oakley towards Antioch. This region has thick, fine sand beds beneath the northeastern and northern areas which correlate moderately well (Cross Sections 5, A, B, and C). In this region, a surficial deposit of Aeolian dune sands occurs, and some of the thicker subsurface fine sands may represent older buried dune fields, which were fed from the Delta Island area sand deposits. Towards the Coast Range, the area has fewer thin sand beds and the western portion, west of Oakley towards Antioch, seems to lack thick sand beds, although well density is very low. Net Sand Thickness - In conjunction with generalized characteristics derived from the cross sections, sand bed distribution across the entire area was assessed by computing net sand thickness in 100 foot intervals for all wells reviewed. Overlay work maps were generated in 100 foot intervals with well locations color coded to depict net sand thickness. Mapping was performed for the 0-100, 100-200, and 200-300 foot depth ranges. Beneath the Fluvial Plain, the net sand thickness maps show sand thickness of 30 feet or more per hundred feet. The thicknesses are composed of 1 or 2 thick sand beds (20 to 30 feet) which correlate well laterally. To the west, the sand thickness rapidly decreases. In the 0-100 foot interval net sand thickness is low, less than 10 to 20 feet. In the Delta Islands, net sand thickness appears to thicken northward from about 30 feet to 60 feet and more per hundred feet beneath Bethel Island. This pattern appeared on all of the net sand thickness work maps. The number and thicknesses of the sand beds appear to increase as net thickness increases. To the west below Jersey Island, low well density does not allow accurate evaluation of sand bed thicknesses to be made. In the Marginal Delta Dune area, net sand thickness appears to be on the order of 30 to 60 feet per hundred feet. The number of sand beds appears to increase, although bed thickness is variable from thin to thick. Local areas of thick net sand thickness appear to occur, possibly related to stream or distributary channels. In the Alluvial Plain, net sand thickness is generally low, less than 20 feet per hundred, and occurs in several thin beds on all maps. However, local pockets or bands of thicker net sand (30 to 40 feet per hundred feet) occur at various depths. These pockets consist of several thin (10 to 20 foot) beds 12 overlying each other, and may represent stream channel deposits. The work maps also showed the general decrease of sand beds westward towards the Fluvial Plain. Finally, along the western edge of the maps, the bottom of the alluvium is reflected by the increasing depth eastward at which pre- alluvium deposits are encountered. The net sand evaluation added appreciably to the development of the depositional models described below. The effort to use them as a tool may be useful for other future purposes such as modeling. However, the work maps were not advanced to a final work product and are not included in this report. Depositional Model of Alluvium Based on the review of drillers’ logs, electrical logs, geologic cross sections, and net sand thickness analysis, a general model of depositional environments responsible for the configuration and character of the sedimentary deposits across the area was developed. The depositional model describes the physical processes which formed the deposits and caused the areal and physical characteristics in different areas. The depositional model is divided into subareas based upon sedimentary characteristics formed by different depositional processes. The model is delineated as four regions on the Base Map. Fluvial Plain - Along the floor of the San Joaquin Valley, a zone of well-defined, thick-bedded (20 to 30 feet) sands and gravels occurs. These few beds appear to occur at distinct levels or depths separated by intervening clay to silt beds, and extend northward in fairly well defined sequences. The sand and gravel beds were probably deposited in stream channels which migrated laterally through time, and are confined within and overlain by flood-plain clay and silt deposits. The setting was probably similar to that which occurs today with northward flowing river channels, distributaries, and sloughs across floodplains of overbank areas. The deposits extend to depths of about 350 feet, below which occur largely fine-grained silts and clays. Delta Islands - North of the Fluvial Plain region is the Delta Islands area (see Base Map). Sand and gravel beds correlate to the Fluvial Plain, but net sand thicknesses and number of beds appear to increase northward. Net sand thickness increases to 60 feet or more per hundred feet beneath much of the Delta Island areas. To the west where well control is limited, the nature of the Delta area is not well documented. The sand beds appear to be somewhat finer-grained than the fluvial plain, 13 with fewer reports of gravel materials. As in other areas, the sand beds exist to depths of about 300 to 350 feet, below which few sands are encountered. The depositional environment for the Delta Islands is interpreted as multiple stream channels meandering between islands. Channels would be active with through-flowing waters, then abandoned as new channels developed. Possibly slower stream flow and tidal fluctuations allowed thicker, fine-grained sand deposits to form. Marginal Delta Dunes - Southwest of the Delta Islands region, an area is defined by numerous thin to thick sand beds as the Marginal Delta Dunes region. Net sand thicknesses are generally greater than 30 feet of sand per hundred feet. The sand beds tend to be similar to the Delta Island area, generally finer-grained sands, but thinner individual beds. Locally, areas of thicker sand beds occur. The depositional environment is envisioned to be a mixture of delta fluvial distributary channels and possibly aeolian dune fields. Between Oakley and northern Brentwood, a surface deposit of rolling gentle hills of relic sand dunes occur. These sand dunes are believed to have been generated by strong winds blowing sand off the delta margins. Some of the deeper sand beds across the Marginal Delta Dunes area are suspected to be similar older dune fields. Alluvial Plain - South of the Marginal Delta Dune area and west of the Fluvial Plain is the final depositional environment, the Alluvial Plain. This area is characterized by thin sand and gravel beds which correlate poorly between wells. Net sand thicknesses are generally low, less than 20 feet of sand per hundred feet, and generally occurring as several beds. Locally, pockets or bands of thicker sand and gravel beds occur where slightly thicker beds may occur. The depositional environment for the Alluvial Plain region is one of small streams draining eastward from the Coast Range foothills to the west. Flood flows of these streams spread out from the hills depositing fine-grained deposits, possibly as mud flows with high sediment content. Stream flows deposited thicker sand and gravel beds which tended to stack upon each other causing the thicker bands of sand beds. The Alluvial Plain deposits thin westward to pinch-out against the Coastal Range foothills. These deposits appear to thicken to about 300 to 350 feet eastward. The sand and gravel beds appear to decrease eastward, so the eastern half of the alluvial plain is dominated by silts and clays. These distal alluvial plain deposits probably interbed with floodplain deposits from the adjacent Fluvial Plain region. The thicker stream deposited sand and gravel bands extend eastward 14 until the sands either pinch out or have not been reached by wells. In the north, the stream deposits appear to reach into the Marginal Delta Dunes area and blends into the sand beds that are present there. Antioch and Byron Areas - These two areas could only be briefly examined due to lack of well control. The Antioch area appears to be a small alluvial plain area with thin sand beds. Possibly, the Plio-Pleistocene non-marine deposits occur at shallow depths and the alluvium is thin in this area. More extensive study towards Antioch would be required to evaluate the area. The Byron area also appears to have few thin sand beds of small alluvial plain area marginal to the greater Fluvial Plain region where fine-grained deposits appear to dominate. Depositional Model of Plio-Pleistocene Non-Marine Deposits As reported in the literature and seen on the cross sections, below the alluvium occur poorly defined Plio-Pleistocene deposits. These non-marine deposits appear to thicken eastward from exposure areas to thicknesses of 1,500 to 2,000 feet below the San Joaquin River. Limited borehole data indicates that these deposits are mostly fine-grained silt, clays and mudstones with few sand beds. Electrical logs indicate that fresh to brackish water quality exists in these deposits, although it is difficult to determine because of their fine grained nature. Regional geologic studies (Bartow, 1991; and Bertoldi and others, 1991) have shown that Miocene marine deposition occurred in the area as shown by the Tertiary marine rocks exposed in the Coast Ranges. During the following Pliocene, the San Joaquin Valley drained to the south to the ocean via the Salinas Valley. The Sacramento Valley drained westward through the Delta area, and the Coast Range locally apparently had not been uplifted as yet. Deposition may have been confined to distal fluvial plains sourced from the Sierra Nevada area, such that little sand was carried into the area. Similar aged fine grained deposits are seen in southern Sacramento County, near Vacaville, and around Rio Vista reaching thicknesses of 2,000 to 2,500 feet. In the Quaternary (mid-Pleistocene) period, the San Joaquin Valley south of Tracy was occupied by a large fresh water lake, Corcoran Lake. The study area appears to have remained in low relief, and fine-grained fluvial plain deposition continued. At about 600,000 years ago, northern San Joaquin River drainage and local Coast Range uplift began. It is suspected that this activity marked the beginning of the alluvium deposition where coarse-grained deposits were formed and carried into the area by the San Joaquin River and eroded off of the uplifting Coast Ranges. 15 III. Ground-Water Conditions Introduction This chapter discusses ground-water conditions in terms of ground-water levels, which are a reflection of ground-water storage, and ground-water quality. Throughout the study area, the primary water-bearing units for water supply purposes exist primarily in the upper 300 to 400 feet of geologic material. From the analyses presented in the previous chapter, there is no apparent basis for subdividing the aquifer system into subunits on a regional scale due to a lack of correlation although locally there are apparent variations in aquifer characteristics, water levels, and water quality. The most extensive collection of historical water level and quality data was provided by the East Contra Costa Irrigation District (ECCID). This data covered the area from Oakley in the north to south of Brentwood, and from west of Highway 4 east toward Discovery Bay. The period of record for the ECCID data began in 1958 and provided an excellent basis to evaluate trends in water levels over time, especially during drought periods. This data was the primary source for the generation of contour maps of equal ground-water elevation and depth-to-water, and water level hydrographs discussed below. Ground-water quality data is also predominantly from this area but is also very limited in scope so that only a few general conclusions could be drawn with respect to questions concerning this topic. Ground-Water Level Hydrographs Representative water level elevation hydrographs of wells monitored by ECCID were constructed and evaluated to assess historical trends. A hydrograph, which is a plot of water level versus time, reflects ground-water storage over time. The factors which affect ground-water levels and storage include seasonal and climatic changes, use patterns (e.g., municipal and agricultural pumping), and artificial and natural recharge. A long-term or permanent decline in ground-water elevation is generally interpreted as an overdraft condition where extraction of ground water exceeds the 16 recharge components. Short-term water level declines may result from climatic conditions such as drought. In this case, overdraft would not exist if water levels recover after the drought period. In areas where ground water is extracted for various purposes, seasonal fluctuations can often be correlated to recharge during the winter period (water level rise) and pumping through spring and summer (water levels fall). The hydrographs analyzed for this study and a well location map are included under Exhibits at the end of this report. Ground-water level data obtained from ECCID spanned from the late 1950's and served as an excellent basis for interpreting ground-water storage over time for a significant portion of the study area. The data indicates that water levels in the east county area have remained fairly stable with no evidence of long term or dramatic declines. Minor shifts in water levels have occurred in two areas of the east county region. Wells located north of Lone Tree Way in Brentwood in the Marginal Delta Dune area have exhibited an upward to relatively flat trend in water levels. The upward trend is exhibited by an increase of approximately two to five feet over the last 25 to 35 years. Wells located in the Alluvial Plain area south of the Marginal Delta Dune area have generally exhibited either stable or slightly declining trends in water levels. The wells which have shown a slightly decreasing trend have had a decline of two to five feet in the last 25 to 35 years, almost a mirror image of the upward trend in the Marginal Delta Dune area. The amount of decline is not considered significant in terms of impacts to either ground-water quantity or quality in the affected area. Climatic and seasonal water level changes are most noticeable in wells located in the western portion of ECCID’s well network. These wells commonly have seasonal or climatic water level changes of five to twenty feet. Wells located in other areas of ECCID do not have pronounced seasonal or climatic water level changes. These wells may be affected by proximity to the Delta whereas the wells located in the western portion of ECCID are likely influenced more by boundary effects caused by proximity to the edge of the ground-water system, i.e., the Coast Range foothills. Long-term water level data were not found for other east County areas. This problem could be addressed by extending the monitoring conducted by ECCID to the other regions including south of Brentwood in the Byron area, the Oakley area, the Discovery Bay area, and east beyond the county line. However, considering that the most significant historical ground-water extraction activities have been focused in the greater Brentwood area, it is expected that the outlying areas would not show a significant deviation from the stability reflected in the ECCID data. In Discovery Bay, long- 17 term monitoring of water levels of the confined unit tapped by its municipal wells would be of key importance with regard to ground-water conditions in that area. Ground-Water Level Contour Maps Regional water level contours were constructed for spring and fall of 1958, 1975, and 1991, and spring or fall of 1977, 1986, and 1996. The 1991 contour maps were augmented with data from Diablo Water District and Discovery Bay. The contour maps were used to assess historical changes in ground-water flow directions since 1958 during time periods which experienced wide variations in precipitation, e.g., during "wet" years (mid 1980's) and "dry" years (mid 1970's, late 1980's). The plots were also used to determine areas which have experienced increases in ground-water pumpage and which have little or no recorded water level data. All the ground-water elevation contour plots show ground-water flow directions from west to east in the southern portion of the study area (Brentwood to Discovery Bay) and from southwest to northeast in the central and northern portions of the area (from Brentwood toward Holland Tract). Immediately south and southwest of Brentwood near ECCID’s Main Canal, there appears to be a flattening of ground-water elevations, possibly resulting from ground-water pumping in the vicinity (an effort should be made in the future to verify the measuring point elevations in this area as the apparent flattening of contours could be a data quality problem). This is most noticeable from 1975 through 1991, when more water level data is available in this area, and does not appear to be developing into a ground-water depression, even during drought periods (1977 and 1991). There is a lack of data south of Brentwood in 1996 and prior to 1975 to evaluate whether the flattening of ground-water levels persists before or after that time period. This area does not appear to have a dramatic affect on water levels either in the Discovery Bay area or in the Brentwood area. The hydraulic gradient is approximately 15 feet per mile in the southern portion of the basin to 20 feet per mile in the northern portion of the basin. The hydraulic gradients have not changed significantly since 1958 with the exception of the flattening of the gradient in the area south of Brentwood since 1975. 18 Depth-to-Water Contour Maps Depth-to-water contour maps were prepared for the same time periods as the water level elevation contours discussed above. These maps, included in the Exhibits section along with the ground- water elevation maps, can be used to assess how depth-to-water in a particular area has changed over time; they can also, for example, serve as a useful reference when assessing available drawdown for well development purposes. Unfortunately, there is a lack of historical water level data west of Highway 4, in the Oakley area, south of Brentwood to Byron, and in the Dutch Slough, Rock Slough, and Indian Slough areas; this lack of data limits the scope of depth-to-water mapping in the overall study area. The depth-to-water maps show that ground water occurs at shallower depths from west to east. These maps are consistent with the hydrographs and elevation contour maps in that they indicate no significant changes over time nor any apparent significant impacts by historical extraction within the area for which data is available. Ground-Water Levels in Newer Brentwood Municipal Wells - Although there is no extensive data on water levels in municipal wells operated by the City of Brentwood, it is known that static levels in the City’s two main well fields (Wells 6, 7, and 8 near Marsh Creek and Wells 11, 12, and 13 to the south) are deeper than the shallower levels reflected in the broad ECCID data base. Static water level readings from Brentwood’s wells indicate that the water level difference may be 20 to 40 feet in magnitude and is most likely caused by the municipal pumping. The City's pumping, however, has not impacted the larger regional system as reflected in the well hydrographs or water elevation contours discussed previously. At least locally, the City should be concerned with how the water level difference between the deeper completion zones of its newer municipal wells and the shallow zones might cause degradation of water quality by inducing downward movement of water quality constituents of local concern (e.g., nitrate). As development of the deepest portion of the aquifer occurs, it would be advisable to monitor the municipal wells separately to determine if a distinction of the aquifer system into shallow and deep units is appropriate. 19 Ground-Water Quality Ground-water quality data was reviewed to assess trends and characteristics of ground water throughout the study area. Data was limited in quantity and distribution, with most concentrated in the greater Brentwood area and within the East Contra Costa Irrigation District. Water quality data is presented in a series of graphs for wells located on the study Base Map under Exhibits at the end of this report. Ground-water quality data posted on maps include concentrations of total dissolved solids (TDS), chloride, and nitrate. As discussed below, because of the limited amount of data, the most significant finding concerning water quality variations throughout the study area is the notably better water quality in Discovery Bay as compared to other areas where data is available. A series of graphs was also used to assess water quality characteristics for this investigation. These graphs were constructed by plotting various water quality constituents versus the depth of the well intake structure; that is, the top of the well perforations or screen. Most notably, there is a strong correlation between nitrate concentration and the depth of the intake structure, which is consistent with the generally understood concept that nitrate degradation occurs as a result of surficial influences. Other constituents also showed a relationship that suggests that water quality improves with depth as discussed below. Total Dissolved Solids - Data on total dissolved solids in ground water in the study area varies widely, although it is characteristically high, up to 1,000 mg/l, in many areas (see TDS map). Discovery Bay is notable for significantly lower TDS in ground water with all measured values between 500 and 600 mg/l. As discussed further below, this information lends support to the theory that the ground-water system in that area may be hydraulically distinct from the depositional areas to the west and perhaps the north. This hydraulic distinction is not apparent from the ground-water elevation maps discussed previously because of a lack of data around Discovery Bay. Other constituents of ground-water quality, including electrical conductivity, were plotted as a function of the depth of the well intake structure. Each of these indicates a slight trend of better water quality with depth. Considering a very strong relationship with nitrate, which is usually derived from surficial sources, it may be possible that there is some degradation in ground-water quality (besides nitrate) that is a result of the same influences. However, the preponderance of the data suggests that water quality is naturally high in TDS (up to 1,000 mg/l) and other constituents 20 such as chloride, and that local degradation may have occurred possibly due to man-made influences. Nitrate - Nitrate in ground water is widely distributed in the study area, with some values exceeding the maximum contaminant level (MCL) set by EPA for drinking water (45 mg/l as nitrate). The eastern portion of the study area is notable as having significantly lower values; the wells in Discovery Bay have no detectable nitrate present. While the occurrence of nitrate in ground water in this area has generally been attributed to agricultural influences, its occurrence is clearly limited to the upper sequences of aquifer materials as reflected in the plot of nitrate concentration versus depth of well intake structures. For the available data, nitrate concentrations decline appreciably for wells completed below 200 feet; i.e., for wells where the top of the perforations are 200 feet or more below the surface. This suggests that, in many cases, nitrate contamination may be mitigable through well design, for example, by incorporation of wells seals to 200 feet and limitation of well screens to depths below 200 feet. Aquifer Confinement The representative hydrographs and contour maps analyzed for this investigation are included at the back of the report under Exhibits. The wells monitored by ECCID are widely distributed throughout the region and are representative of the main aquifer system which occurs in the upper 300 to 400 feet below ground surface. The water level data reflects primarily conditions in the western portion of the study area, with most of that falling within the Alluvial Plain depositional region but extending into the Marginal Delta Dune region around Oakley. Considering the depositional region as well as the consistencies in data from well to well, the aquifer system appears to act locally confined. That is, there appears to be hydraulic continuity from the shallow aquifer materials to the deeper ones as reflected by the similarities in water levels from all wells. The hypothesis of local confinement is supported by the apparent discontinuous nature of aquifer materials as reflected in the cross sections discussed in the previous chapter. Under this model, some local confinement would be expected as a result of the presence of clay beds and would affect the drawdown characteristics of wells, for example. However, these beds are not areally extensive and hydraulic equilibrium would likely be reached between shallow and deep zones when wells are inactive (e.g., in the winter). In the Brentwood area, this is consistent with the experience that well sealing can successfully mitigate nitrate degradation by preventing locally induce downward migration of shallow ground water as a result of deeper pumping. 21 In contrast to the apparent conditions in the Alluvial Plain, municipal wells in Discovery Bay produce from a zone which appears to be confined by an extensive layer of clay material (see Cross Sections 1 and C). The confinement of the main aquifer in the Discovery Bay area is indicated also by the difference in head between the deep zone and a shallow brackish zone which has caused some problems in operation of the municipal well facilities. These problems have been shown to be effectively mitigated by sealing the well through the brackish zone to achieve complete hydraulic isolation of both the deeper aquifer and the well structures from the brackish aquifer. The apparent confinement of the main aquifer at Discovery Bay appears to be representative of the Fluvial Plain region. The same may not be true immediately north into the Delta Islands where the cross section interpretation seems to make confinement more difficult to correlate and there is no water level data for added support. Recharge Sources The study area consists of an aquifer system having a mix of depositional patterns as discussed in Chapter II. From the depositional models, it is not unlikely that there are different sources of recharge of the various aquifer materials which are sources of water supply. From water level data, it is clear that ground water is moving from the Coast Range foothills toward the east through the Alluvial Plain and Marginal Delta Dune regions. As discussed above, there is no clear extensive confinement of aquifer materials in these areas. In contrast, ground water developed in municipal supply wells in Discovery Bay appears to be confined and, when water quality information is considered, it is likely that there is different recharge source as well. One possibility is that the Fluvial Plain region, where Discovery Bay is located, is recharged from the south in a manner that is consistent with the depositional model discussed previously. Again, it should be noted that this is not reflected on the ground-water elevation contour maps primarily because of lack of data around Discovery Bay. Recharge of the Delta Islands may be a combination of fluvial influences from the south but also the hydraulics of the Delta system. The lack of pronounced seasonal and climatic influences on water levels as cited previously underscores the likely significance of the Delta system with regard to recharge. The latter is especially true considering the lack of the correlatable confinement that is a characteristic of the Fluvial Plain. No other conclusions regarding recharge could be made except for those cited above mainly because of the lack of water level information outside of the ECCID area. It should be noted that in some areas, particularly to the north in the Delta Islands and 22 Marginal Delta Dune regions, significant increases in pumpage may have the potential to induce recharge from poor quality, or brackish, water as a result of proximity to Bay and Delta influences. The inability to assess recharge in parts of the study area underscores the need to develop a broader range of water level monitoring outside the boundaries of ECCID. In Discovery Bay particularly, where ground water is relied on for municipal water supply purposes, it would be desirable to investigate ground-water conditions in more detail to the north, south, and east to delineate flow direction and potential recharge influences. Basin Yield Historical conditions as reflected in the hydrographs and contour maps discussed above suggest that, for much of the Alluvial Plain and Marginal Delta Dune regions, where most of the historical data is available, extraction activities have not exceeded the sustainable yield of the ground-water system. Here, sustainable yield, sometimes called "safe" yield, refers to that level at which extraction has not adversely impacted ground-water conditions, e.g. levels, storage, quality, etc. As cited above, stability in ground-water levels and storage reflected in the well hydrographs and the ground-water contour maps. Although it may be stated that the sustainable yield in much of the east County area has not been adversely impacted as reflected by the ground-water level data, less certainty exists at Discovery Bay and other areas, including Brentwood (deeper zones), because of the lack of data and/or short period of record. It is unlikely, however, that sustainable yield, as defined above, has been exceeded because of the general lack of ground-water development throughout much of these other areas. Furthermore, areas in the vicinity of the river and Delta systems have a large source of potential recharge which could offset potential adverse impacts due to increased extraction. Sustainable yield also refers to that level at which ground-water extraction does not degrade water quality. On this matter, less is apparent based on available water quality data in the study area. It is likely that pumping on a local level in the Brentwood area, for example, induces some degradation by nitrate. However, it is also likely that some of these local influences are caused by, and can therefore be mitigated through, well design practices. On a regional scale, significant increases in pumpage could cause migration of poor quality water in some areas, particularly the Alluvial Plain region, which could degrade water quality (e.g., nitrate, TDS). In the Delta areas, increased extraction may not affect quantity, but may induce movement of shallow brackish water that would be a hazard to fresh ground-water sources. Again, these considerations further point to the need for 23 expanded monitoring in parts of the study area to better understand local conditions beyond where historical data is concentrated. 24 IV. Conclusions Data Quantity and Quality Initial efforts to collect and organize information resulted in the development of a large data base of well driller's reports and ground-water levels which formed the basis for addressing the investigation objectives. Ground-water quality data was the most sparse and lacking of the primary categories of information sought for the study. As a result, some firm conclusions could be drawn with respect to the occurrence and distribution of aquifer materials, as well as historical ground-water conditions, but with limited conclusions regarding ground-water quality. Well data in the form of driller's reports permitted construction of geologic cross sections covering the entire study area. These tools can serve various future water supply development needs including targeting depths for exploratory test holes prior to new well construction. Since there was a limited quantity of electrical logs available, which provide precise delineation of lithologies, the cross sections should be reassessed when new logs become available (from new wells). The data did not permit quantification of how much additional pumpage might be sustained in the basin without impacting the sustainable yield. As a result, it is recommended below that any significant incremental pumpage be monitored to determine if sustainable yield is exceeded. This can be accomplished by identifying key representative wells for the purposes of tracking water levels in the form of updated hydrographs and water level contour maps. These tools will permit detection of adverse or downward trends in water levels or flow patterns; they will also allow identification of appropriate local or other corrective measures (e.g., relocation or redistribution of pumpage, augmentation of recharge, etc.). Because of the lack of water quality data, a systematic ground-water quality sampling and testing program is also recommended to more fully assess ground-water quality in the region and to serve as a basis for future ground-water management activities. 25 Hydrogeologic Regions Four ground-water regions were delineated in the study area which are distinguished by the manner in which aquifer materials were distributed and deposited. These include the Alluvial Plain, Fluvial Plain, Delta Islands, and the Marginal Delta Dune. For reference, the aquifer system underlying the City of Brentwood is representative of the Alluvial Plain region; the aquifer system in Discovery Bay is representative of the Fluvial Plain; Bethel Island is central to the Delta Islands regions; and Oakley is within the Marginal Delta Dunes. The western extent of the entire hydrogeologic system is at the Coast Range foothills which represent the most distinct hydrogeologic boundary in the study area. For most of the study area, the extent of aquifer materials capable of yielding quantities of water suitable for municipal and/or agricultural purposes is to depths of 400 feet. Each region has characteristic quantities of aquifer materials (i.e., net sand thickness) that are related to depositional patterns. The depositional models are useful for a number of purposes. For example, differences in the occurence and patterns of aquifer units, as well as ground-water quality and quantity, between the western part of the study area (represented by Brentwood) and the eastern (represented by Discovery Bay as well as the other regions) can be attributed to the natural history (i.e., geology) of the region. The distinctions between the Alluvial Plain and the Fluvial Plain likely include different recharge sources which explains some significant differences in water quality between Brentwood and Discovery Bay, for example. Ground-Water Conditions Water level hydrographs reflect seasonal fluctuations and, in some areas, climatic influences (such as drought periods) on ground water. In general, comparing conditions since the late 1950's to present, the data indicates that there is no apparent overdraft of the ground-water system, suggesting that historical extraction patterns have not exceeded the sustainable yield of the system. However, there may be localized pumping influences around Brentwood that should be investigated further. In that area, newer municipal wells which tap deeper aquifer units (below 300 feet) have apparent lower static water levels than measured in the surrounding ECCID data base. Ground water contour maps, constructed to depict ground-water levels at various times since the late 1950's, reveal patterns and directions of ground-water flow throughout a large portion of the study 26 area from the western edge toward Discovery Bay. The maps indicate that there have been no significant changes in movement of ground water within the study area since the late 1950's. Furthermore, there have apparently been limited, if any, adverse impacts to ground-water storage in the study area as a result historical use patterns. Impacts appear to be limited to the occurrence of elevated nitrate concentrations in shallow ground water which is likely a result of agriculture and, in some cases, possibly septic systems. Ground-Water Quality Ground-water quality data, while sparse, indicates wide variations in TDS and nitrate concentrations. Discovery Bay is notable for relatively better water quality in terms of lower TDS and no detectable nitrate concentrations when compared to areas directly to the west. This is likely attributable to the distinct depositional environments associated with the two areas, as cited previously, as well as differences in historical land use. Nitrate problems in the greater Brentwood area are likely a result of surficial influences by agricultural practices where localized infiltration has caused introduction of nitrogen to shallow ground water. Such problems are most likely best addressed through specific well design features, such as selective well completions and deep annular well seals, to hydraulically isolate the shallow zones from the target completion intervals (i.e., water zones) in supply wells. In the northern hydrogeologic regions, shallow, poor quality water (i.e., brackish) may exist as a result of influence by the Bay in the Delta over geologic time. The extend of this problem can be identified through exploration tools such as electrical logs and may be mitigated through well design. The known shallow brackish zone at Discovery Bay is considered anomalous in that the fluvial depositional model does not suggest a source of the poor quality water. 27 Ground-Water Exploration and Development Potential Based on the geologic evaluation and cross sections, some general conclusions may be drawn regarding future ground-water exploration and development in the study area. In general, exploration should be confined to depths above about 400 feet except within a mile or two of the Coast Range Foothills where depths of exploration would be even shallower. Most alluvium sand and gravels beds occur above about 350 feet depth. Some thin sand or sandstone beds may be found below 400 feet. In the Fluvial Plain region, wells of relatively high yields (up to 2,200 gpm capacity) have been constructed above 400 feet in the Discovery Bay area. However, shallow and possibly deeper brackish water problems have been found which must be avoided. The better water quality (in terms of lower TDS) developed in the municipal wells in Discovery Bay, as compared to the other regions, is likely due to the existence of a separate recharge source to the south. This source is likely related to the depositional pattern of the river system. Development of wells in the Fluvial Plain region, with characteristics similar to the Discovery Bay municipal wells, may be possible particularly north of that community. However, this area does not have a population base to warrant such development at present. It is expected that exploration below 400 feet will not encounter suitable aquifers for water supply purposes. In the eastern Delta Islands, wells of moderate yield appear to have been constructed. From the drillers’ reports, depths of 400 feet appear to be the bottom of exploration potential. Brackish or saline water quality problems, especially in shallow aquifers above 200 feet, may be found as discussed previously. In the Marginal Delta Dunes area, limited exploration has occurred to 400 feet. Potentially moderate yielding wells may be possible, but exploration is needed to evaluate deeper aquifer potential. Potential shallow aquifer problems of brackish water may be present and should be evaluated as part of any exploration effort in that area. In the Alluvial Plain area, local areas of thick alluvial sand and gravel above 350 feet represent the best potential for development of ground-water sources. Two areas have been identified, one to the north near City of Brentwood Wells 6, 7, and 8, and an area to the south near City Well 13. In the southern area, additional exploration to the northeast may allow mapping of the sand beds of the 28 channel sequence. Exploration between the north and south area is recommended to evaluate the possibility of correlation between the two areas, which may reveal a greater distribution of aquifer units suitable for ground-water extraction. Some development of deeper aquifers below 300 feet has occurred, but has resulted in low well yields (less than 400 gpm capacity) due to poor aquifer characteristics, although good water quality was encountered (Brentwood Well 13). In general, it is suspected that high yielding wells (1,000 gpm capacity or more) suitable for municipal or irrigation needs will only be found in the alluvium to about 300 to 350 feet in depth. Shallow water quality has been found to be degraded by the presence of nitrate in the upper 100 to 200 feet of the alluvium zone and must be considered in well development programs. Exploration to the east, outside of the trends of the stream channel sand zones, is not likely to be encouraging based on the results of this subsurface investigation. The area west of Oakley towards Antioch is poorly defined, but is suspected to be a poor ground- water supply region due to lack of alluvium deposits and possible brackish water quality problems. The Byron area shows very low exploration potential due to limited sand beds present and its apparent marginal relationship to the greater Alluvial Plain region in which Brentwood is central as well as representative. Recommendations The east County water entities are in a position to manage ground-water resources at a point in time that impacts of future development can readily be assessed for a system which has been relatively stable over several decades. Considering the vertical extent as well as the quality of aquifer materials present in the study area, the entities should prepare to react to any adverse changes in the historical water level and flow patterns caused by changes in extraction patterns. This need is underscored by the fact that water quality is poor in many areas (e.g., high TDS and nitrate) and the aquifer system is limited areally and vertically (i.e., to depths of about 400 feet) as reflected in the geologic cross sections constructed for this investigation. The east County entities should be concerned with any increment of ground-water extraction that results in downward trends in water levels or shifts in flow direction. The affected entities should consider instituting a program to monitor conditions on a periodic basis. Since the basin extends across multiple boundaries of influence, it would be beneficial to share information in order to completely depict regional ground-water conditions. This program should consist of: 29B:\1997 Job Files\97-131\REPORTInvest of GW Resources.wpd • identification of key wells for water level monitoring and water quality testing. • updating hydrographs for key wells on a semi-annual (spring and fall) basis. • updating water level contour maps on a semi-annual (spring and fall) basis. • production of an annual report which incorporates updated hydrographs, contour maps, and water quality test results; the report should highlight any significant changes in ground-water use patterns. Such a program is conducted in many major ground-water basins in the State. The various maps and hydrographs created for this investigation can serve as initial products of an ongoing monitoring program. These products can be easily interpreted for ground-water management purposes including protection of water quality and limiting of extraction to the sustainable yield of the basin. They would also be useful with efforts to increase sustainable yield, correspondingly increasing pumpage, by management actions such as augmenting recharge and treatment of high TDS and/or nitrate- contaminated water. 30 V. References Atwater, B.F., 1982, Geologic Maps of Sacramento - San Joaquin Delta, California. USGS MF- 1401. Barton, J. Alan, 1991, The Cenozoic Evolution of the San Joaquin Valley, California. USGS Prof. Paper 1501. Berkstresser, C.F., Jr., 1973, Base of Fresh Ground Water - Approximately 3,000 micromhos - in the Sacramento Valley and Sacramento - San Joaquin Delta, California, USGS, WRI 73-40. Bertoldi, C.L., Johnston, R. H. & Evenson, K.D., 1991. Ground Water in the Central Valley, California, a Summary Report, USGS Prof. Paper 1401-A. Brabb, E.E., Sonneman, H.S. & Switzer, J.R., Jr., 1971. Preliminary Geologic Map of the Mount Diablo - Byron Area, Contra Costa, Alameda, & San Joaquin Counties, California. USGS open file report 71-53. California Division of Oil and Gas, 1982, California Oil and Gas Fields Northern California Volume 3, California Department of Conservation, Division of Oil & Gas, TR-10. California State Water Project Authority, May 1956. Investigation of the Sacramento-San Joaquin Delta, Ground Water Geology, Report No. 1. Davis, F.F., & Goldman, H.B., 1958. Mines and Mineral Resources of Contra Costa County, California. California Journal of Mines & Geology, v.54, no. 4. Dibblee, T.W., Jr., 1980(a). Preliminary Geologic Map of the Byron Hot Springs Quadrangle, Alameda & Contra Costa Counties, California. USGS open file report 80-534. 31 Dibblee, T.W., Jr., 1980(b). Preliminary Geologic Map of Antioch South Quadrangle, Contra Costa County, California. USGS open file report 80-536. Dibblee, T.W., Jr., 1980(c). Preliminary Geologic Map of the Tassajara Quadrangle, Alameda & Contra Costa Counties, California. USGS open file report 80-544. Fogelman, R.P., 1982. Compilation of selected ground-water quality data from the San Joaquin Valley, California. USGS open file report 82-0335. Helley, E.J., Lajoie, K.R., Spangle, W.E., & Blair, M.L., 1979. Flatland deposits of the San Francisco Bay Region – their geology and engineering properties, and their importance to comprehensive planning. USGS Prof. Paper 943. Keeter, G.L., 1980. Chemical Analyses for selected wells in San Joaquin County and part of Contra Costa County, California. USGS open file report 80-420. Page, R.W., 1974. Base and Thickness of the Post-Eocene Continental Deposits in the Sacramento Valley, California. USGS WRI 73-45. Page, R.W., 1986. Geology of the Fresh Ground-Water Basin of the Central Valley, California, with Texture Maps and Sections. USGS Prof. Paper 1401-C. Sorenson, S.K., 1981. Chemical quality of ground water in San Joaquin and part of Contra Costa Counties, California. USGS WRI 81-26. Thesken, R.S. and Adams, R.L., 1995. South Oakley and East Brentwood Gas Fields. California Department of Conservation, Division of Oil, Gas & Geothermal Resources, Publication No. TR46. Wagner, D.L., Jennings, C.W., Bedrossian, T.L., and Bertugno, E.J.; compilers, 1981. Geologic map of the Sacramento quadrangle. California Division Mines and Geology, Regional Geologic Map Series, Map No. 1A; scale 1:250,000. 32 Wagner, D.L., Bertugno, E.J., and McJunkin, R.D., compilers, 1990. Geologic map of the San Francisco-San Jose quadrangle. California Division Mines and Geology, Regional Geologic Map Series, Map No. 5A; scale 1:250,000. Welch, L.E. 1977. Soil Survey of Contra Costa County, California. USDA, Soil Conservation Service. E X H I B I T S -10 -5 0 5 10 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-22J1 4-1 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-14m1 4-2 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 25 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-22b2 4-5 wlh.h:\projects\east county\data\summarydata.wb3 10 15 20 25 30 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-22e1 4-7 wlh.h:\projects\east county\data\summarydata.wb3 10 15 20 25 30 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-16j1 4-12 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 25 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-15G1 4-14 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-15A1 4-16 wlh.h:\projects\east county\data\summarydata.wb3 25 30 35 40 45 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-16D1 4-23 wlh.h:\projects\east county\data\summarydata.wb3 15 20 25 30 35 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-21B1 4-27 wlh.h:\projects\east county\data\summarydata.wb3 35 40 45 50 55 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-17e1 4-32 wlh.h:\projects\east county\data\summarydata.wb3 40 45 50 55 60 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-7Q1 4-37 wlh.h:\projects\east county\data\summarydata.wb3 38 43 48 53 58 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R2E-24J1 4-56 wlh.h:\projects\east county\data\summarydata.wb3 38 43 48 53 58 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R2E-18B1 4-59 wlh.h:\projects\east county\data\summarydata.wb3 30 35 40 45 50 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-20l1 4-61 wlh.h:\projects\east county\data\summarydata.wb3 70 75 80 85 90 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R2E-25M1 4-64 wlh.h:\projects\east county\data\summarydata.wb3 37 42 47 52 57 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R2E-24A1 4-66 wlh.h:\projects\east county\data\summarydata.wb3 40 45 50 55 60 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-6N1 5-2 wlh.h:\projects\east county\data\summarydata.wb3 50 55 60 65 70 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-7M1 5-3 wlh.h:\projects\east county\data\summarydata.wb3 20 25 30 35 40 45 50 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-9N1 5-10 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 25 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-4L1 5-13 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 25 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-9H1 5-15 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 25 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-3N1 5-16 wlh.h:\projects\east county\data\summarydata.wb3 -5 0 5 10 15 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-3D1 5-18 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 25 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-4D1 5-21 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T2N/R3E-33m1 5-22 wlh.h:\projects\east county\data\summarydata.wb3 30 35 40 45 50 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-20J1 5-31 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T2N/R3E-30J1 5-33 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 25 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T2N/R3E-31H1 5-35 wlh.h:\projects\east county\data\summarydata.wb3 10 15 20 25 30 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T2N/R3E-32m1 5-36 wlh.h:\projects\east county\data\summarydata.wb3 20 25 30 35 40 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-6H1 5-37 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T2N/R3E-29Q1 5-39 wlh.h:\projects\east county\data\summarydata.wb3 15 20 25 30 35 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-16f1 5-45 wlh.h:\projects\east county\data\summarydata.wb3 35 40 45 50 55 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-8e1 5-55 wlh.h:\projects\east county\data\summarydata.wb3 25 30 35 40 45 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-5P1 5-56 wlh.h:\projects\east county\data\summarydata.wb3 10 15 20 25 30 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R3E-5C1 5-57 wlh.h:\projects\east county\data\summarydata.wb3 35 40 45 50 55 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R2E-1E1 5-66 wlh.h:\projects\east county\data\summarydata.wb3 50 55 60 65 70 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T1N/R2E-12L1 5-72 wlh.h:\projects\east county\data\summarydata.wb3 5 10 15 20 Water Level Elevation (feet, asl)1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 Date (year) Water Level Elevation Hydrograph ECCID Well T2N/R3E-30F1 5-73 wlh.h:\projects\east county\data\summarydata.wb3 10 20 30 40 50Depth to Water (feet)1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 Date (year) Depth to Water Hydrograph Discovery Bay Well #4 wlh.h:\projects\east county\data\summarydata.wb3 20 40 60 80 100 Nitrate Concentration (mg/L)0 50 100 150 200 250 300 350 400 Depth to Top of Screen (ft) Nitrate wlh.h:\projects\east county\data\summarydata.wb3 500 1000 1500 2000 2500 3000 EC (umho/cm)0 50 100 150 200 250 300 350 400 Depth to Top of Well Screen (ft) wlh.h:\projects\east county\data\summarydata.wb3 50 100 150 200 250 300 Chloride Concentration (mg/L)0 50 100 150 200 250 300 350 400 Depth to Top of Well Screen (ft) wlh.h:\projects\east county\data\summarydata.wb3 100 150 200 250 300 Alkalinity (mg/L)0 50 100 150 200 250 300 350 400 Depth To Top of Well Screen (ft) wlh.h:\projects\east county\data\summarydata.wb3 7 7.2 7.4 7.6 7.8 8 8.2 pH0 50 100 150 200 250 300 350 Depth To Top of Well Screen (ft) wlh.h:\projects\east county\data\summarydata.wb3 50 100 150 200 250 300 Sodium Concentration (mg/L)50 100 150 200 250 Depth To Top of Well Screen (ft) wlh.h:\projects\east county\data\summarydata.wb3 An Evaluation of Geological Conditions, East Contra Costa County, 2016 APPENDIX 3b     AN EVALUATION OF GEOLOGIC CONDITIONS  EAST CONTRA COSTA COUNTY            Prepared for:  East Contra Costa County Agencies        Prepared by:  Luhdorff & Scalmanini, Consulting Engineers, Inc.          March 29, 2016      Page i   TABLE OF CONTENTS   1. INTRODUCTION ............................................................................................................................ 1  2. GEOLOGY ..................................................................................................................................... 2  2.1 Coast Ranges Geology ....................................................................................................................... 2  2.2 Mesozoic Great Valley Sequence ...................................................................................................... 2  2.3 Tertiary‐Paleogene Sedimentary Rocks ............................................................................................ 3  2.4 Late Tertiary‐Neogene Units ............................................................................................................. 3  3. QUATERNARY GEOLOGIC HISTORY ............................................................................................... 4  4. GROUNDWATER HYDROLOGY ...................................................................................................... 5  4.1 Brentwood Area ................................................................................................................................ 7  4.2 Tracy Area ......................................................................................................................................... 7  4.3 Clifton Court Area ............................................................................................................................. 7  5. CONCLUSIONS .............................................................................................................................. 7  6. REFERENCES ................................................................................................................................. 8        Page 1   1. INTRODUCTION This report was prepared for the following local agencies located within the eastern portion of Contra  Costa County:   Byron‐Bethany Irrigation District   City of Brentwood   Contra Costa County   Diablo Water District   East Contra Costa Irrigation District   Town of Discovery Bay  These agencies authorized and funded the work to develop a fuller understanding of the geologic setting  underlying the Contra Costa County portion of the Tracy Groundwater Subbasin (DWR 5‐22.15). Other  cooperating agenicies included Contra Costa Water District and City of Antioch. The location of the Tracy  Subbasin is shown on Figure 1.   The work described in this report was also undertaken to better understand differences among three  subareas within the Tracy Subbasin, which are shown on Figure 2. The subareas are as follows:  1. The portion of the subbasin that occurs within Contra Costa County.  2. The portion of the subbasin that occurs within San Joaquin County north of Old River.  3. The portion of the subbasin that occurs within San Joaquin and Alameda counties south of Old  River.  Local agencies in the Tracy Subbasin have engaged in efforts to comply with the 2014 Sustainable  Groundwater Management Act (SGMA). The above subareas have been discussed among local agencies  as potential boundaries for formation of Groundwater Sustainability Agencies and Groundwater  Sustainability Plans. They also represent divisions in previous general water resource planning, including  AB3030 Groundwater Management Plans, reflective of variations in groundwater occurrence and  availability, and jurisdictional considerations. This report focuses on the geologic history of freshwater  sediments from which groundwater is extracted for beneficial uses as defined and regulated under SGMA.  The work is intended to provide a basis for hydrogeologic conceptualization of the subbasin and, through  its design and approach, to identify connections or distinctions that will aid in the development of  Groundwater Sustainability Plans. In accordance with the objectives of the funding agencies, the work  was also undertaken to assess any basis for modifying the Tracy Subbasin boundaries to enable more local  control over groundwater resources.  March 29, 2016 AN EVALUATION OF GEOLOGIC CONDITIONS EAST CONTRA COSTA COUNTY     Page 2   2. GEOLOGY The study area for this report is the northwestern portion of the San Joaquin Valley where it merges in  the Delta area with the Sacramento Valley of the larger geologic province of the Great Valley (see Figure  3). The study area encompasses the eastern portion of the Contra Costa County and western San Joaquin  County to south of the City of Tracy. Fresh groundwater is produced for municipal, domestic, and irrigation  from underlying unconsolidated alluvial fan and fluvial sedimentary deposits. Much irrigation water is also  supplied by surface water from various sloughs and ditches, particularly in the eastern portion of the study  area.   2.1 Coast Ranges Geology West of the San Joaquin Valley lies the Coast Ranges geologic province of uplifted, older, highly deformed,  and well‐consolidated geologic units. The immediate range is termed the Diablo Mountains, but is  subdivided here as the Mt. Diablo area north of Livermore Valley, and the southern Diablo range to the  south. These areas have had a long history of sedimentary deposition, deformation, and uplift. The  geologic units are a record of the plate tectonic evolution of California. The units exposed in the Mt. Diablo  Mountains extend eastward below the San Joaquin valley at great depths. These units are divided into  three broad categories: the Mesozoic Great Valley Sequence, the Tertiary (Paleogene) sedimentary rocks,  and the late Tertiary (Neogene) sedimentary rocks. These exposures in the Diablo Mountains are shown  on Plate 1.   Regional geologic relationships are best seen on the San Francisco‐San Jose Quadrangle map (Wagner and  others, 1990). Numerous more detailed geologic maps and reports cover the area. The most accessible  detailed maps are by T.W. Dibble, Jr. from the Dibblee Foundation series and which were used in preparing  this report. Reports summarizing the geologic history include the classic Hackel (1966), and the more  recent Bartow (1991), which is the main source for this report.   2.2 Mesozoic Great Valley Sequence The Mesozoic (pre‐65 million years (m.y.)) Great Valley Sequence consists of deep water marine  sedimentary deposits grading eastward into shallow marine and deltaic deposits. These units were  deposited in the forearc basin in the convergent plate tectonic setting of the subduction of the Pacific  Plate below the North American Plate. The Andes‐like volcanics to the east in the Sierra Nevada area was  the source of the sediment carried into the forearc basin. The Great Valley Sequence occurs in the Mt.  Diablo area and the southern Diablo range, and underlies younger deposits below the San Joaquin Valley.  In the Mesozoic of the northwestern San Joaquin Valley area, a structural element formed that influenced  depositional patterns for a long period of geologic time. The Stockton Fault appears to be initially a down‐ thrown to the south normal fault with greater thickness of the Great Valley Sequence to the south. The  cause of the Stockton Fault is not clear from a tectonic framework, and different theories have been  March 29, 2016 AN EVALUATION OF GEOLOGIC CONDITIONS EAST CONTRA COSTA COUNTY     Page 3   proposed (Bartow, 1991). Subsequent activity on the fault shows opposite movement as a reverse fault  with down to the north relative motions.  2.3 Tertiary-Paleogene Sedimentary Rocks Beginning in the early Tertiary, the plate tectonic configuration began to change as plate subduction  angles altered, and the change to a transform boundary of the ultimate San Andreas Fault system began  to evolve. During much of the Paleogene (about 59 to 23 m.y.), the San Joaquin Valley and Coast Ranges  were dominated by alternating sequences of marine inundations of shallow marine deposits and periods  of non‐marine sequences (Bartow, 1991). Even during deposition of non‐marine sequences, marine  deposition continued north of the Stockton Fault and in the southern San Joaquin Valley.   The Paleogene sedimentary rocks are exposed on the northern edge of the Mt. Diablo area, west of the  City of Brentwood (see Plate 1). These deposits are largely marine sandstones and shales, and their  exposure pattern may reflect the Sherman Island and Midlands Faults. The units extend below the Valley  floor north of the Stockton Fault.  During the Tertiary Period, the Stockton Fault assumed a down to the north reverse fault movement. On  the uplifted southern side of the fault, the Paleogene sedimentary units are absent for 20 miles or more  to the south (Bartow, 1985; 1991). This area is identified as the Stockton Arch where the Paleogene rocks  were never deposited or removed by erosion. South of the Stockton Arch, marine conditions also  continued interrupted by non‐marine periods. By the end of the Paleogene, the marine conditions  persisted in the south valley. Drainage from the Sierra region appears to be to the south (Bartow, 1991).  Exposures of the Paleogene rocks are not present to south of the southern Diablo range, along the western  San Joaquin Valley, but are present below the valley south of the Stockton Arch.  2.4 Late Tertiary-Neogene Units In the Neogene, plate tectonics evolution was dominated by the northward migration of the triple junction  plate boundary as the strike‐slip fault system of San Andreas Fault zone formed. East of the fault zone,  elements of the Coast Range were deformed and uplifted to positive elements. At times, these  deformations yielded sediment into the San Joaquin Valley. The Stockton Fault movement appears to  have ended in the early Neogene with total reverse offset of about 10,000 feet. The Stockton Arch may  have acted as a positive element as Bartow (1991) shows the area as a divide between drainage to the  Sacramento Valley to the north and to the south to the marine embayment in the San Joaquin Valley.  North of the Stockton Arch, shallow marine conditions also persisted, including at times, across the Mt.  Diablo area, until at least 9 m.y.  The earliest Neogene (Miocene 23 to 5.3 m.y.) units exposed along the northern edge of Mt. Diablo area  are shallow marine transitioning to non‐marine. Further south, exposures are more limited until a larger  area wraps around south of Mt. Diablo area towards the Livermore valley (see Plate 1). The units tend to  be predominated by sandstone to pebbly sandstones.  March 29, 2016 AN EVALUATION OF GEOLOGIC CONDITIONS EAST CONTRA COSTA COUNTY     Page 4   In the younger Neogene (Pliocene 5.3 to 2.5 m.y.), the San Andreas Fault system was well established and  deformation and uplift of the Coast Range to the east was occurring. Sierra Nevada drainages appear to  continue to the remaining southern San Joaquin Valley marine embayment (Bartow, 1991). The exposures  of these younger Neogene units overlie the older Neogene units around the Mt. Diablo area and southern  Diablo range. Where exposed, the unit is dominated by pebbly sandstone to the north and  conglomerate/sandstones to the south. These appear to be sourced from the uplifted Coast Range  elements and deposited by alluvial fans.  Both the older and younger Neogene units extend eastward beneath the northern San Joaquin Valley, but  are poorly understood even from deep oil and gas well logs. Part of the cause of this is that the state  Division of Oil and Gas field classification designates post‐Paleogene units as undifferentiated non‐marine  units. Gas fields in western San Joaquin County indicate 3,000 to 4,000 feet of post‐Paleogene units, but  includes younger Quaternary units. Electric logs tend to show the Neogene units are dominated by  monotonous sequence of fine‐grained sediment of sandy claystones and mudstones with few sand beds.  The units also appear to contain at best brackish to saline water, although it is difficult to define base of  fresh water without interbedded sand beds.  By the end of the Neogene, movement along the San Andreas Fault system had isolated the southern San  Joaquin marine embayment from the ocean (Bartow, 1991). The impounded water probably transformed  into brackish‐ to fresh‐water lakes. Drainage in the San Joaquin Valley continued to flow southward  towards the subsiding lake basin area. Drainage from the lakes appears to have flowed from the basin  across the San Andreas Fault to the Salinas Valley and Monterey Bay area. To the north of the Stockton  Arch, area drainage in the Sacramento Valley appears to continue to drainage westward north of the Mt.  Diablo area.  3. QUATERNARY GEOLOGIC HISTORY The youngest geologic unit in the San Joaquin Valley area is the Quaternary (2.5 m.y. to present)  unconsolidated sedimentary units of sand, gravel, silt and clay that cover the valley floor. Most of these  deposits are probably of the longer, older Pleistocene Epoch (2.5 to 0.01 m.y.), the Great ice Age when  alpine ice fields and glaciers occurred along the summit of the Sierra Nevada. High runoff and sediment  yield from the Sierra Nevada appears to continue to largely drain to the lakes in southern San Joaquin  Valley. Drainage out of the lakes may have persisted across the San Andreas Fault system to the Salinas  valley for at least the older Pleistocene.  The plate tectonic configuration of the San Andreas Fault was well formed in the Pleistocene. The Diablo  ranges continued to be uplifted as shown by the deformed Neogene units around the Mt. Diablo area (see  Plate 1). The westward tilting of the Sierra Nevada block begun in the Pliocene also continued in the  Quaternary. From these uplifted areas, smaller stream drainages formed alluvial fans off the Diablo  Mountains into the valley. Larger drainages from the Sierra Nevada formed broad alluvial‐fluvial plains  March 29, 2016 AN EVALUATION OF GEOLOGIC CONDITIONS EAST CONTRA COSTA COUNTY     Page 5   from the east. In the center of the valley, low gradient stream channels and flood plains were formed,  flowing southward to the southern lakes.  Just prior to about 600,000 years before present, a large lake termed the Corcoran Lake flooded nearly all  the San Joaquin Valley northward to the Tracy area. A widespread blue lake clay was deposited across the  San Joaquin Valley known as the Corcoran Clay, or E‐clay. This clay has not been identified further north  into the Delta area of Contra Costa County, or in the Sacramento Valley. The cause of the formation of the  Corcoran Lake, and smaller subsequent lakes, is not clear. Possibilities include that the San Andreas Fault  system blocked the western drainage outlet of the lakes in the south, at least for brief periods.  Alternatively, higher runoff due to climatic conditions may have been the principal cause that formed the  lakes.  The northern extent of the Corcoran Lake, including the deposition of the E‐Clay, appears to have been in  the Stockton‐Tracy area. The cause of this is not clear. An alluvial fan dam across the valley (Atwater,  1986) or a structural‐caused drainage divide by differential subsidence between the north and south  across the Stockton Arch may explain the northernmost extent. Other possible causes could be structural  blockage of the drainage out of the Sacramento Valley or regional tilting of the northern San Joaquin  Valley.  It is tempting to suggest that the high base‐level of the Corcoran Lake disrupted drainage patterns in the  San Joaquin Valley. Possible subsequent opening of a shorter drainage pattern of the Sacramento River  across the San Francisco Bay area, caused San Joaquin drainage to be diverted to the Delta area, until the  drainage pattern of northward flowing San Joaquin River developed through the remainder of the  Pleistocene.  4. GROUNDWATER HYDROLOGY The groundwater hydrology of the northwestern San Joaquin Valley area that is the focus of this report is  relatively poorly known. The reasons of this are multifold. Groundwater usage is limited to eastern Contra  Costa County and the Tracy area to the south. Under most of western San Joaquin County in the Delta,  few groundwater wells exist as surface water is the source for irrigation use within delta islands. Fresh  groundwater aquifers are limited to relatively shallow depths of 500 to 700 feet in the Contra Costa  County area, and to 1,600 feet in the Tracy area. Oil and gas electric logs indicate that at greater depths  fine‐grained clays and mudstones with very few sand beds occur, and contain saline to brackish water.  Some saline waters at shallow depths above the fresh water bearing sands have been found along the  trend of the Old River channel.  Hydrogeologic studies have tended to cover areas in the Sacramento Valley north or east of the Delta  area. In the San Joaquin Valley, studies have covered areas on the west side of the valley studies have  covered areas from Tracy south (Hotchkiss and Balding, 1971) and on the east side of the valley south of  March 29, 2016 AN EVALUATION OF GEOLOGIC CONDITIONS EAST CONTRA COSTA COUNTY     Page 6   the Stanislaus River (Page and Balding, 1973). Even regional studies tend to have little information for the  northwestern San Joaquin Valley area (Page, 1986).  Luhdorff & Scalmanini (1999) performed a study of eastern Contra Costa County groundwater for five  local water agencies. The focus of the study was the uppermost 500 feet in which most water wells were  completed. A depositional facies model was developed from examination of over 500 well logs that were  used to assess sand bed characteristics and their extent. The facies consisted of a fluvial plain grading into  a delta island area in the north. This was bound to the west by a marginal delta dunes area. An alluvial  plain area extends and thins westward to the older geologic units exposed in the Mt. Diablo area. This  depositional model was incorporated into an AB3030 Groundwater Management Plan covering the  sphere of influence for Diablo Water District, an Environmental Impact Report for conjunctive use wells  by Diablo Water District, and a water master plan for Town of Discovery Bay.   Electric logs from Oil and Gas were also examined for the nature of geologic units at greater depths. The  top of the electric logs tend to be at 800 feet or greater depths. These logs generally show fine‐grained  geologic units with few sand beds. The depth to base of fresh water is difficult to discern in available  electric logs because of the lack of sand beds. In the 1999 study of groundwater hydrology in eastern  Contra Costa County, the base of fresh water was not systematically mapped. The base of freshwater has  been mapped previously in the general area by Page (1971) and Berkstresser (1973).   Most groundwater studies in the westerns San Joaquin County have been centered on the Tracy area. The  Tracy Regional Groundwater Management Plan (GEI, 2007) and a related hydrogeologic assessment (GEI,  2007) were reviewed for the geologic cross‐sections and interpretations. These reports characterized  groundwater wells in the immediate Tracy area, and additional review of these wells was not attempted  for the present study.  For the present study, a systematic map of the base fresh water aquifers in the area using electric logs for  oil and gas wells obtained through the state Division of Oil, Gas & Geothermal Resources website was  developed (see Plate 1). As mentioned previously, depths to the top of most logs and the fine‐grained  character of the sedimentary units below 700 feet were limitations in the north. Selection of logs to review  was based on the top of the log being less than 1,000 feet in depth. Base of fresh water aquifers was based  on thick sand beds with high resistivity values and the character of the self‐potential response on the  electric logs. Deeper sandy units, probably sandy clays or mudstones, with low resistivity values and  indeterminable self‐potential characteristics were considered to be non‐viable as aquifers.  The elevation of the base of freshwater aquifers determined from oil and gas logs were plotted on a base  map (see Plate 1) and manually contoured. Contour lines of one hundred feet were drawn, but is variable  based on well control. The resulting map is a hydrostratigraphic map based on the nature of the bed (sand  and/or gravel) and containing fresh water. The determined beds at each location should not be  considered, in general, as lithostratigraphic equivalent (i.e., connected to other beds in different wells  March 29, 2016 AN EVALUATION OF GEOLOGIC CONDITIONS EAST CONTRA COSTA COUNTY     Page 7   across the map), or necessarily time‐stratigraphic equivalent (i.e., of the same geologic age). For example,  the beds defining the deepest areas on the map are probably not connected or time equivalent to beds  at much shallower depths to the east or west. The resultant map represents the most detailed  examination of base of fresh water in the north San Joaquin Valley study area.  4.1 Brentwood Area In the Brentwood area, the depth of freshwater aquifer descends eastward from the edge of the valley.  The deepest area occurs near the Contra Costa County line to ‐1,200 feet. Further east the depth of  freshwater aquifer rises to ‐600 feet. Several gas fields are shown further east (see Plate 1) which show  base of fresh water as 100 feet depth or less (California Division of Oil & Gas, April 1983). However it is  not known exactly how these values were determined.  4.2 Tracy Area In the Tracy area, the depth of freshwater aquifer descends eastward from the edge of the valley. A larger,  deeper depression occurs beneath the City of Tracy to depths of ‐1,600 feet. This depression appears to  bend and extend eastward roughly along the trend of the Stockton Fault (see Plate 1). Further east the  depth of freshwater aquifer rises to ‐500 to ‐600 feet elevation. The Lathrop Gas field lists the base of  freshwater at a depth of 300 feet, though the method of determination is not evident.  4.3 Clifton Court Area The base of freshwater determined for the Brentwood and Tracy areas are generally are similar to  published base of fresh water by Page (1971) and Berkstresser (1973). Between these two areas, is termed  the Clifton Court area. Although well control is relatively sparse in this area, anomalously shallow  elevations of base of freshwater occur further east. Contouring of the area shows a possible ridge‐like  extension eastward from the edge of the valley. Further eastward, depths of the base of freshwater  decline to ‐800 feet to ‐900 feet elevation and extend eastward, then rises to the east to ‐600 feet  elevation. The maximum low across the Clifton Court area appears to be 300 feet shallower in the  Brentwood area (‐1,200 feet elevation), and possibly 700 feet shallower than in the Tracy area (‐1,600  feet elevation). If this interpretation of a ridge‐like feature is correct, the cause is not clear. It may be a  possible fault uplift or deformation on the south side of the Vernalis fault. The age of the Vernalis Fault is  not well known (Bartow, 1991), but it is at least Neogene (Miocene to Pliocene?) and may be younger  (Quaternary?). No surface expression has been noted to the fault and if this configuration exists, it may  influence groundwater flow around the ridge, or at least impede any northwest flow from the south at  depths below ‐400 feet elevation.  5. CONCLUSIONS The geologic history of the northwestern San Joaquin Valley as described in this report provides a  framework for hydrogeologic conceptualization of the Tracy Groundwater Subbasin. Key features of the  March 29, 2016 AN EVALUATION OF GEOLOGIC CONDITIONS EAST CONTRA COSTA COUNTY     Page 8   geologic history are reflected in exposures of Mesozoic Great Valley Sequence, and Tertiary and late  Tertiary sedimentary rocks in the Diablo Mountains. These rocks represent the western boundary of the  Tracy Subbasin.   While the interpreted geologic history consists of multiple possible explanations for certain features, the  rocks in the Mt. Diablo range north of Livermore Valley and the southern Diablo range reflect distinctions  between the northern and southern portions of the groundwater subbasin including variations in the base  of fresh water. Additionally, the apparent northern extent of the Quaternary Corcoran Lake has  implications in groundwater hydrology, particularly through the occurrence of the Corcoran Clay. The  Corcoran Clay is prominent as a demarcation between the primary upper and lower freshwater aquifer  sequences of the San Joaquin Valley and affects vertical groundwater moment including recharge,  demarcates water quality boundaries, and it is an important factor in well construction standards  throughout the San Joaquin Valley. The absence of the Corcoran Clay in the Contra Costa County subarea  reflects a distinction in the hydrogeology across the Tracy Subbasin that is recognized locally and should  be reflected in the development of groundwater conceptualizations for the subbasin.  6. REFERENCES Atwater, Brian F.; Adam, David P.; Bradbury, J. Platt; Forester, Richard M.; Mark, Robert K.; Lettis, William  R.; Fisher, G. Reid; Gobalet, Kenneth W.; Robinson, Stephen W. 1986. A fan dam for Tulare Lake, California,  and implications for the Wisconsin glacial history of the Sierra Nevada. Geological Society of America  Bulletin, Volume: 97 Issue: 1  Bartow, J.A. 1985. Map showing Tertiary stratigraphy and structure of the Northern San Joaquin Valley,  California, Field Studies Map MF‐1761, Scale 1:250,000.  Bartow, J.A. 1991. The Cenozoic Evaluation of the San Joaquin Valley, California. U.S. Geological Survey,  Professional Paper 1501.  Berkstersser, Jr., C.F. 1973. Base of fresh ground water approximately 3,000 micromhos in the Sacramento  Valley and Sacramento‐San Joaquin Delta, California. U.S. Geological Survey, Water‐Resources  Investigations Report 73‐40.  California Division of Oil & Gas. 1982. California Oil and Gas Fields. Northern California, Volume 3.   Dibblee, Jr., T.W. 2006. Geologic Map of the Antioch South and Brentwood Quadrangles, Contra Costa  County, California. Dibblee Geology Center Map DF‐193, Scale 1:24,000.  Dibblee, Jr., T.W. 2006. Geologic Map of the Byron Hot Springs and Clifton Court Forebay Quadrangles,  Contra Costa, Alameda, and San Joaquin Counties, California. Dibblee Geology Center Map DF‐195, Scale  1:24,000.  March 29, 2016 AN EVALUATION OF GEOLOGIC CONDITIONS EAST CONTRA COSTA COUNTY     Page 9   Dibblee, Jr., T.W. 2006. Geologic Map of the Midway and Tracy Quadrangles, Alameda and San Joaquin  Counties, California. Dibblee Geology Center Map DF‐243, Scale 1:24,000.  GEI Consultants. 2007. Hydrogeologic Assessment Report for the Tracy Subbasin. Prepared for City of  Tracy. January.  GEI Consultants. 2007. Tracy Regional Groundwater Management Plan. Submitted to City of Tracy. March.  Hackel, O. 1966. Summary of the Geology of the Great Valley. In Geology of Northern California, Bulletin  190, E.H. Bailey, ed. San Francisco, California: United States Geological Survey, California Division of Mines  and Geology.  Hackel, O. 1966. Summary of the Geology of the Great Valley. In Geology of Northern California, Bulletin  190, E.H. Bailey, ed. San Francisco, California: United States Geological Survey, California Division of Mines  and Geology.  Hotchkiss, W.R. and Balding, G.O. 1971. Geology, hydrology, and water quality of the Tracy‐Dos Palos area,  San Joaquin, California. U.S. Geological Survey. Open‐File Report 72‐169.  Luhdorff & Scalmanini Consulting Engineers. 1999. Investigation of Groundwater Resources in the East  Contra Costa Area. Prepared for five water agencies. March.  Page, R.W. 1973. Base of fresh ground water (approximately 3,000 micromhos) in the San Joaquin Valley,  California. Hydrologic Atlas 489.  Page, R.W. 1986. Geology of the fresh ground‐water basin of the Central Valley, California, with texture  maps and sections. Professional Paper 1401‐C.  Page, R.W. and Balding, G.O. 1973. Geology and quality of water in the Modesto‐Merced area, San Joaquin  Valley, California, with a brief section on hydrology. Water‐Resources Investigations Report 73‐6.  Wagner, D.L., Bortugno, E.J. and McJunkin, R.D. 1991, Compilers. Geologic Map of the San Francisco ‐ San  Jose Quadrangle. California Geological Survey, Regional Geologic Map No. 5A, 1:250,000 scale.      Figures    Sources: Esri, DeLorme, NAVTEQ, TomTom, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo, and the GIS User Community Figure 1Location MapTracy Subbasin ´ 0 10 205 Miles Legend Tracy Subbasin \\SERVER_PE2900\Public\Tom Elson\000 Sunol ACRP rev CEQA analysis 2016feb\GIS\Tracy Subbasin\Figure 1.mxd DWR5-22.15 SACRAMENTO SACRAMENTO SOLANO SAN JOAQUIN SOLANO SACRAMENTO SOLANO CONTRA COSTA CONTRA COSTA SOLANO STANISLAUS ALAMEDA ALAMEDA MERCED SANTA CLARA SANTA CLARA Sources: Esri, DeLorme, NAVTEQ, TomTom, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo, and the GIS User Community Figure 2Location MapTracy Subbasin Subareas ´ 0 10 205 Miles Legend Tracy Subbasin \\SERVER_PE2900\Public\Tom Elson\000 Sunol ACRP rev CEQA analysis 2016feb\GIS\Tracy Subbasin\Figure 2.mxd SACRAMENTO SACRAMENTO SOLANO SAN JOAQUIN SOLANO SACRAMENTO SOLANO CONTRA COSTA CONTRA COSTA SOLANO STANISLAUS ALAMEDA ALAMEDA MERCED SANTA CLARA SANTA CLARA Sources: Esri, DeLorme, NAVTEQ, TomTom, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo, and the GIS User Community Figure 3Geology Study Area ´ 0 10 205 MilesLegend Tracy Subbasin Geology Study Area \\SERVER_PE2900\Public\Tom Elson\000 Sunol ACRP rev CEQA analysis 2016feb\GIS\Tracy Subbasin\Figure 3.mxd     Plate !( !(!( !(!( !(!( !( !( !( !( !( !(!( !( !(!( !(!(!( !( !( !( !(!( !( !( !(!( !(!( !( !(!(!(!( !( !(!( !( !( !( !( !(!(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !( !( !(!( !(!(!(!( !( !( !(!( !( !( !(!(!( !( !( !(!(!(!( !( !( !( !( !(!(!( !( !( !( !( !( !(!(!( !( !(!( !( !( !( !( !(!( !(!(!( !( !( !(!( !(!( !(!( !( !( !( !( !( !( !(!( !(!( !(!( !( !( !( !( !( !(!(!(!( !( !( !(!( !( !( !(!(!(!( !( !( !( !( !( !(!( !( !(!( !( !( !( !( !( !( !( !(!( !( !( !(!(!(!( !( !( !(!( !( !(!(!( !(!(!( !( !( !( !( !(!( !( !(!( !(!( !( !( !( !(!(!( !( !( !( !( !(????????????????????????????????????? ? ? ? ? ? ? N L R ? ? 2K 5R 4E 26K 29M ? 14H 13P ? 12A 29? 29A 11N? 10Q? 5J -274 9Q -683 9N -672 1Q -899 <-169 <-699 2R -717 9A -812 1E <610 1B <504 8Q <826 36A -930 33K -1131 24C -750 11N -98810? -8739R -1500 9B -1234 8J -1662 8D -17327C -1332 6J -1995 4G -1090 3B <-868 26N -218 15A <762 13L -886 12D -997 11D -710 4F <-949 34K -892 33H -892 22F -982 20N -856 16H -817 15D -801 10D -587 4Q <-597 4J <-522 2F <-597 1K <-977 34P -532 26A -600 25R -748 23E -310 11Q -744 10R -634 11Q -519 6A <-635 5A <-940 4A <-967 33H -720 25C -794 11A -600 10A <991 10P -827 3L <-838 2F <-567 1A <-530 34E -806 30Q -348 29H -650 27Q -806 8K <-822 16R -861 15N -873 9K <-857 8H <-848 7B <-890 7P <-890 6P <-784 6A <-984 5E <-733 5B <-785 4D <-780 4J <-890 3Q <-889 34A -136034E -1115 29l -1443 27C -1505 27c -1605 25N -1383 25H -1103 24M -1096 23K -1290 23B -1266 22M -1427 20B -1453 15C -1410 15N -1480 15K -1418 14M -1170 10B -1080 10D -1408 34M -177? 36D <-970 32H -1054 26F -791? 22D <-507 21N -1022 17B? -833 12N <-293 11R <-786 10B <-586 10N <-595 32J <-937 23Q <-488 14Q <-519 14K <-496 10J <-770 28R -1230 23F <-860 20B -1235 19C <-989 11C <-846 6H <-1136 3R? <-619 31F <-793 29C <-746 28B <-962 27M <-823 18P <-729 10R <-927 17H <-914 16D <-908 16E <-950 16C <-947 11K <-853 11F <-858 10J <-911 10F <-895 3R <-1303 3J <-1032 14L -1125? 32M -1264? 26L? <-926 21B/H -916 24F <-580? 26E <-890? 14C <-1012 14R? <-1007 12A? <-1125 8A <-926 15G -1466 10N -1257 26? <-449 25N -1480 >770 dText >720d ? >768d 16B -262? >600 d !!U D R DIBBLEE FND DF-193 TRACY bfw 1200' d V E R N A LIS FA U LT D U RSTOC KTONFAULTLATHO Pbfw 300'dUNION ISLAND bfw 300'd ROBERTS ISLAND bfw 75'd MCDONALD ISLAND bfw < 100' d DUTCH SLOUGH bfw 800' dSHER MANISLANDFAULTRIVER BREAK bfw 200' d EAST BRENTWOOD bfw 300' d !D U MIDLANDSFAULT!$R U D VERNALIS bfw 1,050' dBLACKBUT TEFAULTU D LIVERMORE VALLEY DIBBLEE FND DF-195 DIBBLEE FND DF-243 -1300-9 0 0 -1200 -6 0 0 -2 0 0-400-800 -1400-1000-700-500-1600-8 0 0 -900-1000-900-1400-1000-1000-400-800-800 -1 6 0 0-500-800-900 -1 2 0 0 -800 -7 0 0 -6 0 0 -6 00 -8 0 0 -700-800-200-1 2 0 0 -4 0 0 -8 0 0 -1 2 0 0 -1000-800-1000-600-600-400-900 -1200 -800-1 0 0 0 -600 -600-800-600-1 0 0 0 -1200-1000-1 0 0 0 3SR5E 1SR5E 2SR5E 1NR5E 3SR4E 2SR4E 2NR5E 3SR3E 2SR3E 3SR2E 1SR3E 1SR4E1SR2E 2SR2E 1NR4E 1NR2E 2NR4E 1NR3E 3NR5E 2NR3E 3NR4E 4SR5E4SR2E4SR3E4SR4E 1NR1E 1SR1E 2SR1E 3SR1E 3NR2E 2NR2E 4SR1E 3NR1E 2NR1E 3NR3E 3NR3E 3NR2E 2NR6E 1NR6E 2NR2E 3NR6E 1SR6E 3SR6E 2SR6E 4SR6E 2NR1E Sources: Esri, HERE, DeLorme, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo, MapmyIndia, © OpenStreetMap contributors, and the GIS User Community X:\2014 Job Files\14-126 East Contra Costa County GSP\430 Basin Boundaries - Geology\East County Oil and Gas Logs\Wells with O&G logs pulled_24x36.mxd Well Location Map, Geologic Map and Base of Freshwater Aquifers Map ¯ 0 2 41Miles Quaternary Sedimentary Units Not shown except locally i.e. Qoa - older alluvium deposits TERTIARY Upper Neogene - (Pliocene) Nonmarine Deposits Lower Neogene - (Miocene) Marine & Nonmarine Deposits Paleogene - (Paloecene to Oligocene) Marine Deposits Mesozoic Great Valley Sequence Note: Coast Range Surficial geology from Dibblee Foundation Maps as shown. See originals for detailed geologic legends and descriptions. Geologic Legend Faults concealed below Quaternary alluvium in San Joaquin Valley - Location approximate U: Upthrown side; D: Down dropped side R: Reverse Fault Source from: DF-193, 195 - Sherman Island Fault DF-195 - Southern Midland Fault Wagner etal - Northern Midland Fault Bartow (1991) - Stockton Fault and Vernatis Fault Oil and Gas borehole with Electric Log 12A Well location I.D. -1400' Elevation base of fresh water aquifers <-900 Elevation Top of E-log; bfw aquifers less than value > 1200 Select water wells with E-logs depth to base fresh water greater than depth shown Name Gas Field bfw 300d Base fresh water 300 feet depth MESOZOIC U R D Structure Contour Map base of Freshwater Aquifers -100 -200 Elevation Contour lines - 100 feet Contour interval - variable Well Construction Table APPENDIX 3c Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)Antioch‐‐ShallowBlossom Well38.0021007‐121.7883016 61.00 44.11 60‐88 1.00‐27.00 88Antioch Monitoring ShallowWilbur Deep38.0128991‐121.7670016 61.00 21.86 101‐106‐40.00‐45.00 106Antioch Monitoring ShallowWilbur Shallow38.0128991‐121.7670016 61.00 21.86 53‐81 8.00‐20.00 81BBID Private Shallow1 JNJ37.906128‐121.6419204 26.63 24.96 105‐120‐78.37‐93.37 120BBID‐‐Shallow3 Byron37.8684118‐121.6412186 32.28 31.25 50‐70‐17.72‐37.72 70BBID Private Shallow4 Bruns37.8168913‐121.5991577 35.87 34.43 45‐65‐9.13‐29.13 65BBID‐‐Shallow5 Binn37.8506993‐121.6238007 24.42 23.46‐‐‐‐‐‐45BBID Private Composite2 Casing37.8691565‐121.6544579 45.43 44.88 71‐163‐25.57‐117.57 163BBID‐‐Composite6 Byer37.8742‐121.6398 31.63 31.23‐‐‐‐‐‐185BBID Private Unknown10 SM237.888253‐121.650808 40.46 38.46‐‐‐‐‐‐‐‐BBID‐‐Unknown10A Taylor37.888769‐121.6518 41.66 41.23‐‐‐‐‐‐‐‐BBID‐‐Unknown10C Marsh37.8898‐121.648728 37.42 36.04‐‐‐‐‐‐‐‐BBID Private Unknown11 TN137.884492‐121.650344 40.95 39.16‐‐‐‐‐‐‐‐BBID Private Unknown12 TN237.881764‐121.671483 59.91 59.14‐‐‐‐‐‐‐‐BBID Private Unknown13 M37.87395‐121.652722 41.07 40.10‐‐‐‐‐‐‐‐BBID Private Deep14 GNO37.889861‐121.642331 30.32 29.22207‐212, 229‐238, 244‐253, 273‐279, 349‐356‐‐‐‐‐‐BBID Private Unknown7 Hoffman 137.889672‐121.6787208 74.43 71.01‐‐‐‐‐‐‐‐BBID Private Unknown8 Casing 237.869144‐121.659658 51.00 49.82‐‐‐‐‐‐‐‐BBID Private Unknown9 SM137.900664‐121.649669 37.85 35.38‐‐‐‐‐‐‐‐BBID‐‐Unknown9d Abreu37.868411‐121.641219 33.38 32.53‐‐‐‐‐‐‐‐BBID‐‐Unknown9e Hagen37.896042‐121.651319 37.86 36.16‐‐‐‐‐‐‐‐Brentwood Monitoring ShallowBG‐137.9638969‐121.6933943 71.22 71.60 40‐5531.2216.22 55Brentwood Monitoring ShallowBG‐237.9589412‐121.6917498 62.09 62.50 22.5‐37.5 39.5924.59 38Brentwood Monitoring ShallowBG‐337.9546062‐121.6824842 55.60 56.20 20‐3535.6020.60 35Brentwood Abandoned ShallowWELL 0137.93‐121.682‐‐61.46 100‐132‐99.00‐131.00 132Brentwood Monitoring DeepMW‐14 Deep37.9620001‐121.6957004 72.76 71.20 284‐315‐211.24‐242.24 324Brentwood Monitoring DeepMW‐14 Int.37.9620001‐121.6957004 72.76 71.20200‐210, 220‐230‐127.24‐157.24 240Brentwood Production DeepWell 0637.9547875‐121.6940894 58.47 58.51 250‐300‐241.53‐291.53 305Brentwood Production DeepWell 0737.9563571‐121.692278‐‐57.66 265‐295‐207.34‐237.34 300Brentwood Production DeepWell 0837.957838‐121.69167‐‐60.21225‐315‐164.79‐254.79 325Brentwood Production DeepWell 0937.954972‐121.6853986‐‐54.58 210‐230‐155.42‐175.42 230Brentwood Production DeepWell 1137.9297678‐121.6849955‐‐63.74 255‐365‐191.26‐301.26‐‐Brentwood Production DeepWell 1237.9247368‐121.6839359‐‐66.86350‐380, 430‐450‐283.14‐383.14 610Brentwood Production DeepWell 1337.9221317‐121.6826703‐‐68.35350‐380, 430‐480‐281.65‐411.65 510Brentwood Production DeepWell 1437.95803502‐121.6954421‐‐68.00 285‐315‐285.00‐315.00 340Brentwood Production DeepWell 1537.9583661‐121.6853304‐‐56.41239‐259,289‐324‐182.59‐267.59 345Brentwood Monitoring CompositeMW‐14 Shallow37.9620001‐121.6957004 72.76 71.20 114‐144‐41.24‐71.24 154BrentwoodAbandoned ProductionCompositeWELL 0237.93‐121.682‐‐61.46 80‐208‐79.00‐207.00 208BrentwoodAbandoned ProductionCompositeWELL 0437.93‐121.682‐‐61.46 126‐165‐125.00‐164.00 165Brentwood Production CompositeWell 10A37.92166667‐121.7008333‐‐91.85 52‐72, 135‐182 39.85‐90.15 21011/14/2020Page 1 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)Brentwood Production UnknownWELL 03‐‐ ‐‐ ‐‐ ‐‐112‐142‐‐ ‐‐146BrentwoodAbandoned ProductionUnknownWELL 05‐‐ ‐‐ ‐‐ ‐‐60‐120‐‐ ‐‐135Brentwood Production UnknownWell 08A‐‐ ‐‐ ‐‐ ‐‐225‐315‐‐ ‐‐325DWD Monitoring ShallowStonecreek MW‐16037.978122‐121.683968 30.76 28.99100‐110, 140‐150‐69.24‐119.24 160DWD Private DeepBethel Island (Sugar Barge Marina‐Well Head)38.027155‐121.613661‐6.00‐3.01 317‐333‐323.00‐339.00 333DWD Monitoring DeepCreekside MW37.9812138‐121.6911215 29.54 29.60 230‐240‐200.46‐210.46 380DWD Monitoring DeepGlen Park MW37.9740743‐121.6866247 35.54 34.71220‐230, 260‐290‐184.46‐254.46 300DWD Monitoring DeepStonecreek MW‐30037.978122‐121.683968 30.47 28.99230‐240, 280‐290‐199.53‐259.53 300DWD Monitoring DeepStonecreek MW‐36037.978122‐121.683968 30.70 28.99 340‐350‐309.30‐319.30 360DWD Production DeepGlen Park Well37.973909‐121.6850365 38.32 38.80230‐245, 260‐300‐191.68‐261.68 315DWD Production DeepSouth Park37.9860934‐121.6330831‐3.50‐1.64204‐264, 284‐299‐207.50‐302.50 323DWD Production DeepStonecreek PW37.9781927‐121.6840086 24.00 28.97 220‐295‐196.00‐271.00 305DWDProduction DeepKNIGHTSEN COMMUNITY WATER SYSTEM‐Well Head37.9709328‐121.6667157 29.91 27.36 235‐275‐205.09‐245.09 305DWD Production DeepKNIGHTSEN ELEMENTARY SCHOOL‐WELL 337.9679868‐121.6613267 29.59 27.60 395‐415‐365.41‐385.41 415DWD Production DeepRock Island (Westside pump #2)37.9817757‐121.6239122‐5.00 2.90240‐270, 284‐292‐245.00‐297.00 320DWD Production CompositeWELL 01 ‐ STANDBY37.988‐121.682‐‐16.85 100‐170‐99.00‐169.00 170DWD Irrigation CompositeKnightsen School Irrigation (#2)37.9678611‐121.6612623 29.43 27.62167‐191, 210‐230‐137.58‐200.58 230DWD Production UnknownDelta Mutual (east side pump)‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DWD Production UnknownWillow Park Marina38.0080033‐121.6313385‐‐5.85‐‐‐‐‐‐‐‐Discovery Bay Monitoring Shallow1BMW‐14037.9102996‐121.5993985 4.31 2.71 100‐130‐95.69‐125.69 140Discovery Bay Monitoring Shallow4AMW‐15237.9009991‐121.6187989 11.67 4.01 122‐142‐110.33‐130.33 152Discovery Bay Monitoring Shallow7MW‐11537.8941889‐121.6183417 11.86 4.71 95‐105‐83.14‐93.14 115Discovery Bay Monitoring Deep1BMW‐34337.9102996‐121.5993985 4.38 2.71270‐289, 309‐338‐265.62‐333.62 343Discovery Bay Monitoring Deep4AMW‐35737.9009991‐121.6187989 11.54 4.01 307‐347‐295.46‐335.46 357Discovery Bay Monitoring Deep6MW‐25037.9028008‐121.5994988 6.60 3.89200‐210, 230‐240‐193.40‐233.40 25011/14/2020Page 2 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)Discovery Bay Monitoring Deep6MW‐35037.9028008‐121.5994988 6.60 3.89280‐290, 330‐340‐273.40‐333.40 350Discovery Bay Monitoring Deep6MW‐41037.9028008‐121.5994988 6.54 3.89 390‐400‐383.46‐393.46 410Discovery Bay Monitoring Deep7MW‐33037.8941889‐121.6183417 11.94 4.71 310‐320‐298.06‐308.06 330Discovery Bay Production DeepWELL 01B37.9102795‐121.5994883 6.13 2.71271‐289, 308‐340‐264.87‐333.87 350Discovery Bay Production DeepWELL 0237.9038164‐121.6019194 9.29 2.62 245‐335‐235.71‐325.71 348Discovery Bay Production DeepWELL 04A37.9009652‐121.6187989 14.82 108.72 307‐347‐292.18‐332.18 357Discovery BayEmergency BackupDeepWELL 05A37.8904152‐121.6155029 16.29 4.91251‐281, 307‐347‐234.71‐330.71 357Discovery Bay Production DeepWELL 0637.9023176‐121.5997724 8.47‐‐270‐295, 305‐350‐261.53‐341.53 360Discovery Bay Production DeepWELL 0737.8941889‐121.6183417 7.00 4.71 282‐292‐275.00‐285.00 346Discovery BayInactive ProductionUnknownWELL 0137.901‐121.603‐‐2.41‐‐‐‐‐‐‐‐Discovery BayInactive ProductionUnknownWELL 0337.901‐121.603‐‐2.41‐‐‐‐‐‐‐‐Discovery BayInactive ProductionUnknownWELL 0437.901‐121.603‐‐2.41 307‐347‐‐‐‐357Discovery BayAbandoned ProductionUnknownWELL 05‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐ECCID Monitoring Shallow4‐137.92487399‐121.6367714‐‐28.32‐‐‐9.13‐29.13 10ECCID Monitoring Shallow4‐637.92581823‐121.665247‐‐53.87‐‐‐9.13‐29.13 10ECCID Monitoring Shallow4‐1837.93988606‐121.6398046‐‐24.60‐‐‐9.13‐29.13 10ECCID Monitoring Shallow4‐5737.9260609‐121.6785219‐‐60.90‐‐‐9.13‐29.13 10ECCID Monitoring Shallow5‐237.95444444‐121.6941667 73.00 58.14‐‐‐‐‐‐20ECCID Monitoring Shallow5‐337.91710984‐121.6580936‐‐42.11‐‐‐‐‐‐10ECCID Monitoring Shallow5‐1437.95644057‐121.642851‐‐18.70‐‐‐‐‐‐10ECCIDMonitoring Shallow5‐2237.974141‐121.657877‐‐17.20‐‐‐‐‐‐11ECCID Monitoring Shallow5‐3337.98935‐121.679441 13.30 13.30‐‐‐‐‐‐11ECCID Monitoring Shallow5‐3437.98194444‐121.6777778 14.00 18.50‐‐‐‐‐‐11ECCID Monitoring Shallow5‐3537.977313‐121.678539 24.30 27.34‐‐‐‐‐‐11ECCID Monitoring Shallow5‐3637.973701‐121.675596 27.40 27.40‐‐‐‐‐‐11ECCID Monitoring Shallow5‐3737.963534‐121.679699 40.60 40.60‐‐‐‐‐‐11ECCID Monitoring Shallow5‐3837.95972044‐121.6780277‐‐43.40‐‐‐‐‐‐10ECCID Monitoring Shallow5‐3937.985299‐121.664114 12.50 12.50‐‐‐‐‐‐11ECCID Monitoring Shallow5‐5137.94391393‐121.6771962‐‐54.10‐‐‐‐‐‐10ECCID Monitoring Shallow5‐73‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐11ECCIDAg. IrrigationShallowWell #1 (4‐54)37.91819‐121.69843 85.90 85.90 85‐1650.90‐79.10 165ECCIDAg. IrrigationShallowWell #6 (4‐60)37.92567‐121.66253 49.50 50.30 30‐5019.50‐0.50 50ECCIDAg. IrrigationShallowWell #11 (4‐61‐A)37.9178003‐121.6700016 55.00 55.50 50‐1005.00‐45.00 100ECCIDAg. IrrigationShallowWell #1337.91787‐121.68204 64.00 65.72 145‐185‐81.00‐121.00 185ECCIDAg. IrrigationCompositeWell #3 (4‐55)37.91817‐121.70336 95.00 96.20113‐197, 281‐365‐16.80‐268.80 365ECCIDAg. IrrigationCompositeWell #4 (5‐62)37.91818‐121.70114‐‐83.12 68‐125, 175‐195 15.12‐111.88 200ECCIDAg. IrrigationCompositeWell #4 Old (4‐56)37.9177987‐121.6972999 87.00 83.80 68‐125, 175‐195 18.80‐111.20 20311/14/2020Page 3 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)ECCIDAg. IrrigationCompositeWell #5 (4‐57)37.92526‐121.67739‐‐60.90115‐125, 170‐175, 195‐200, 220‐245, 270‐290‐54.10‐229.10 290ECCIDAg. IrrigationCompositeWell #9 (4‐58)37.91444444‐121.7002778‐‐97.0090‐106, 118‐126, 180‐1947.00‐97.00 210ECCIDAg. IrrigationCompositeWell #1437.91782‐121.63033 26.51 25.82 200‐300‐174.18‐274.18 330ECCIDAg. IrrigationUnknownWell #2 (5‐30)37.91774‐121.65954 40.30 40.30‐‐‐‐‐‐‐‐ECCID Monitoring UnknownAnderson (4.66)37.92416667‐121.7 89.00 86.00‐‐‐‐‐‐‐‐DDWSmall Community SystemShallowBALDOCCHI WATER SYSTEM‐Well Head37.868416‐121.641222‐‐ ‐‐100‐110‐100.00‐110.00‐‐DDWSmall Community SystemDeepBEACON WEST‐Well 138.046‐121.642‐‐8.54 230‐260‐229.00‐259.00 260DDWSmall Community SystemDeepKNIGHTSEN COMMUNITY WATER SYSTEM‐Well Head37.9709328‐121.6667157 29.91 27.36235‐255, 275‐295‐234.00‐294.00 305DDWSmall Community SystemDeepWILLOW MOBILE HOME PARK‐Well Head38.046‐121.642‐‐8.54 292‐332‐283.46‐323.46 410DDWSmall Community SystemDeepWILLOW PARK MARINA‐East Well38.017‐121.642‐‐7.62 250‐310‐242.38‐302.38 400DDWSmall Community SystemDeepWILLOW PARK MARINA‐West Well38.017‐121.642‐‐7.62 250‐310‐242.38‐302.38 340DDWSmall Community SystemCompositeKNIGHTSEN ELEMENTARY SCHOOL‐NORTH WELL37.959‐121.642‐‐16.19167‐191, 210‐230‐166.00‐229.00 230DDWSmall Community SystemCompositeKNIGHTSEN ELEMENTARY SCHOOL‐SOUTH WELL37.959‐121.642‐‐16.19167‐191, 210‐230‐166.00‐229.00 230DDWSmall Community SystemUnknownANCHOR MARINA‐Well Head‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownANGLER S RANCH #3‐WELL 0238.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownANGLERS SUBDIVISION 4‐WELL 1 ‐ 1696 Taylor38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐11/14/2020Page 4 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DDWSmall Community SystemUnknownANGLERS SUBDIVISION 4‐WELL 2 ‐ 1398 Taylor38.046‐121.682‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownANGLERS SUBDIVISION 4‐WELL 3 ‐ 1698 Taylor38.017‐121.682‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownBAY STANDARDS‐Well Head37.901‐121.682‐‐78.76‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownBETHEL BAPTIST CHURCH‐Well Head38.017‐121.642‐‐7.62‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownBETHEL HARBOR‐WELL38.046‐121.642‐‐8.54‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBETHEL ISLAND GOLF & RESORT‐WELLHEAD38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBETHEL ISLAND LODGE‐WELL 01‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBETHEL ISLAND MUTUAL WATER CO‐WELL 138.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBETHEL ISLAND MUTUAL WATER CO‐WELL 2‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBETHEL MARKET‐WELLHEAD38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBETHEL MISSIONARY BAPTIST‐Well Head37.959‐121.682‐‐49.94‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBIG OAK MOBILE HOME PARK WATER‐Well Head ‐ West well37.988‐121.682‐‐16.85‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBIG OAK MOBILE HOME PARK WATER‐Wellhead‐ East well37.988‐121.682‐‐16.85‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBLAZING SADDLE BAR & GRILL‐WELL 01‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐11/14/2020Page 5 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DDWSmall Community SystemUnknownBLUE TIP TRAILER PARK WATER‐WELL HEAD37.959‐121.682‐‐49.94‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownBON GUSTOS‐Bathroom Sink37.889643‐121.640885‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownBON GUSTOS‐Well Head37.901‐121.642‐‐28.30‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownBONNIE & CLYDES SALOON‐Well Head38.017‐121.642‐‐7.62‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownBRENTWOOD CREEK FARM‐WELL 1 ‐ OFFICE‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBRENTWOOD CREEK FARM‐WELL 2 ‐ CAMP 137.93‐121.603‐‐3.31‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBRENTWOOD CREEK FARM‐WELL 3 ‐ CAMP 237.93‐121.563‐‐3.71‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBRENTWOOD MISSIONARY BAPTIST‐Well Head37.93‐121.682‐‐61.46‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBRIDGEHEAD CAFE‐Well Head38.017‐121.761‐‐10.04‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBRIDGEHEAD RENTALS SWS‐WELL 01‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBYRON AIRPORT‐Well Head37.843‐121.642‐‐66.57‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBYRON CORNERS INC‐Well Head37.872‐121.642‐‐32.03‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBYRON INN‐Well Head37.85032‐121.622765‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownBYRON UNITED METHODIST‐WELL HEAD37.959‐121.721‐‐95.77‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownCALIENTE ISLE  WATER SYSTEM‐WELLHEAD38.017‐121.682‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownCAMINO MOBILEHOME‐WELL37.872‐121.642‐‐32.03‐‐‐‐‐‐‐‐11/14/2020Page 6 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DDWSmall Community SystemUnknownCARSON SWIM SCHOOL‐WELL HEAD37.959‐121.721‐‐95.77‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownCASA DEL RIO WATER SYSTEM‐Well Head38.017‐121.642‐‐7.62‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownCECCHINI WATER‐WELL37.901‐121.563‐‐4.11‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownCECCHINI WATER‐WELL 2‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownCHURCH OF JESUS CHRIST‐Well Head37.959‐121.721‐‐95.77‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownCOLONIA SANTA MARIA‐Well Head37.901‐121.682‐‐78.76‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownCRUISER HAVEN MARINA‐Well Head37.93‐121.563‐‐3.71‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownD ANNA YACHT CENTER‐Well Head38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownDAVIS CAMP  *CL 10/08‐east well (south)37.959‐121.682‐‐49.94‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownDAVIS CAMP  *CL 10/08‐WELL 3‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownDAVIS CAMP  *CL 10/08‐west well (north)37.959‐121.682‐‐49.94‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownDELTA KIDS CENTER *CL 2/07‐Well Head37.959‐121.682‐‐49.94‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownDELTA MUTUAL WATER COMPANY‐East Well37.988‐121.642‐‐ ‐0.47‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownDELTA MUTUAL WATER COMPANY‐West Well37.988‐121.642‐‐ ‐0.47‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownDELTA SPORTSMAN‐Well Head38.017‐121.642‐‐7.62‐‐ ‐‐ ‐‐ ‐‐11/14/2020Page 7 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DDWSmall Community SystemUnknownDNA PLANT WATER SYSTEM *CL04/02‐Well Head‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownDUTCH SLOUGH WATER WORKS‐Well Head38.017‐121.642‐‐7.62‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownEBRPD BLACK DIAMOND MINES‐WELL0137.959‐121.88‐‐856.26‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownEBRPD ROUND VALLEY WATER SYSTEM‐Well Head37.872‐121.761‐‐287.99‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownEXCELSIOR MIDDLE SCHOOL‐Well Head37.872‐121.642‐‐32.03‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownFARMERS DAUGHTER WATER SYS *CLOSED*‐Well Head37.901‐121.682‐‐78.76‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownFARRAR PARK PROPERTY OWNERS‐Well Head38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownFLAMINGO MOBILE MANOR‐Well Head38.017‐121.603‐‐ ‐4.31‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownFRANKS MARINA‐New Well‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownFRANKS MARINA‐Well Head38.017‐121.603‐‐ ‐4.31‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownGAS N SAVE‐Well Head37.988‐121.682‐‐16.85‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownGAYLORD CONTAINER COMPANY‐WELL 03‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownGENOS DELI STATION‐Well Head37.901‐121.642‐‐28.30‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownGOLDEN HILLS CHURCH‐WELL 01‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐11/14/2020Page 8 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DDWSmall Community SystemUnknownGOLF CLUB AT RODDY RANCH‐WELLHEAD37.93‐121.801‐‐475.46‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownHOLLAND RIVERSIDE MARINA‐well 2 ‐ East Well37.959‐121.563‐‐4.77‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownHOLLAND RIVERSIDE MARINA‐Well Head ‐ West Well37.959‐121.603‐‐2.91‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownHOLY CROSS CEMETERY‐Well Head38.017‐121.761‐‐10.04‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownHONOLULU GRILL *CL 10/07‐Well Head‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownJEHOVAHS WITNESSE CHURCH  *CL 2/13‐Well Head‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownJOES ISLAND RESTAURANT‐WELLHEAD38.017‐121.642‐‐7.62‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownKNIGHTSEN COMMUNITY WATER SYSTEM‐Well 3‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownLA PALOMA HIGH SCHOOL‐WELL 01‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownLAST RESORT & MARINA LLC‐Well Head38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownLIGHTHOUSE BAPTIST CHURCH‐Well Head37.959‐121.721‐‐95.77‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownLINDQUIST LANDING MARINA‐Well Head37.988‐121.603‐‐3.42‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownLITTORNO & PANFILI WATER SYSTEM‐WELL HEAD38.017‐121.761‐‐10.04‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownLONE TREE MEDICAL & DENTAL‐Well Head‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐11/14/2020Page 9 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DDWSmall Community SystemUnknownLOS VAQUEROS INTERPRETIVE CENTER‐SOURCE‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownLOS VAQUEROS MARINA BLDG‐SOURCE‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownLUNDBORG LANDING  *CL 2/09‐well38.017‐121.603‐‐ ‐4.31‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownMACS OLD HOUSE‐Well Head38.017‐121.761‐‐10.04‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownMARIN FOOD SPECIALTIES‐Well Head‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownMARINA MOBILE MANOR‐NEW WELL‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownMARINA MOBILE MANOR‐Well Head38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownMARINE EMPORIUM RICHARDS YACHT‐Well Head38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownMARINER COVE MARINA‐Well Head38.046‐121.682‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownMARS HARBOR‐WELL 01‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownNEIGHBORHOOD CHURCH‐Well Head37.93‐121.682‐‐61.46‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownNEW DOCS MARINA‐Well Head38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownOAKLEY MUTUAL WATER COMPANY‐NORTH WELL ‐ 4384 SANDMOUND37.988‐121.642‐‐ ‐0.47‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownOAKLEY MUTUAL WATER COMPANY‐SOUTH WELL ‐ 4508 SANDMOUND37.988‐121.642‐‐ ‐0.47‐‐ ‐‐ ‐‐ ‐‐11/14/2020Page 10 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DDWSmall Community SystemUnknownOAKLEY MUTUAL WATER COMPANY‐WELL 3‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownORIN ALLEN YOUTH REHAB FACILITY‐WELL37.872‐121.642‐‐32.03‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownORIN ALLEN YOUTH REHAB FACILITY‐Well 2‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownORWOOD RESORT‐WELL 2 ‐ WEST WELL37.93‐121.603‐‐3.31‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownORWOOD RESORT‐WELL 3 ‐ PICNIC AREA37.93‐121.603‐‐3.31‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownPARK MARINA‐Well Head38.017‐121.642‐‐7.62‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownPG & E WATER SYSTEM‐Well Head‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownPLEASANTIMES MUTUAL WATER CO‐WELL  2 ‐ 4520 STONE38.017‐121.603‐‐ ‐4.31‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownPLEASANTIMES MUTUAL WATER CO‐Well 1 ‐ 4282 STONE38.017‐121.603‐‐ ‐4.31‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownPLEASANTIMES MUTUAL WATER CO‐WELL 3 ‐ 4441 WILLOW38.017‐121.603‐‐ ‐4.31‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownRAYNERS GROCERY SWS **CLOSED**‐Well Head‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownRIVERVIEW MARINA SWS‐Well Head38.017‐121.603‐‐ ‐4.31‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownRIVERVIEW MOTEL‐Well Head38.017‐121.761‐‐10.04‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownRIVERVIEW WATER ASSOCIATION‐WELL 1 BEACON HARBOR38.046‐121.642‐‐8.54‐‐‐‐‐‐‐‐11/14/2020Page 11 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DDWSmall Community SystemUnknownRIVERVIEW WATER ASSOCIATION‐WELL 2 END OF WILLOW RD38.046‐121.642‐‐8.54‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownRUSSOS MOBILE PARK‐Well Head38.046‐121.603‐‐ ‐‐ ‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownSANDMOUND MUTUAL‐3160 STONE ROAD WELL38.017‐121.642‐‐7.62‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownSANDMOUND MUTUAL‐3810 STONE ROAD WELL38.017‐121.642‐‐7.62‐‐ ‐‐ ‐‐ ‐‐DDWSmall Community SystemUnknownSANDY POINT MOBILE HOME PARK‐Well Head38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownSANTIAGO ISLAND VILLAGE‐WELL 0138.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownSUNSET HARBOR‐Well Head38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownTONYS FAMILY RESTAURANT‐WELL HEAD38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownTUGS‐Well Head38.017‐121.642‐‐7.62‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownVILLA DE GUADALUPE‐WELL37.901‐121.682‐‐78.76‐‐‐‐‐‐‐‐DDWSmall Community SystemUnknownWILLOWEST MARINA WS‐WELLHEAD‐‐‐‐‐‐ ‐‐‐‐‐‐‐‐‐‐DWR‐‐Shallow01N03E17E001M37.9335‐121.6747 55.90 54.87 113‐123‐57.10‐67.10 123DWR Observation Shallow01N04E20L001M37.9146‐121.5631‐2.88‐5.66‐‐‐‐‐‐20DWR Observation Shallow01N04E20P001M37.9122‐121.5611‐2.88‐5.68‐‐‐‐‐‐20DWR Observation Shallow01N04E20P002M37.9143‐121.5624‐4.28‐7.67‐‐‐‐‐‐20DWR Observation Shallow01N04E29C002M37.9092‐121.5619‐3.98‐6.68‐‐‐‐‐‐20DWR Monitoring Shallow01N04E29D001M37.91250‐6.20‐‐‐‐‐‐‐‐20DWRObservation Shallow01N04E29P001M37.899‐121.5639‐7.28‐7.68‐‐‐‐‐‐20DWR Observation Shallow01N04E30G001M37.905‐121.573 4.07‐7.67‐‐‐‐‐‐20DWR Observation Shallow01N04E30H001M37.904‐121.5715‐2.17‐4.67‐‐‐‐‐‐20DWR Observation Shallow01N04E30J001M37.9016‐121.5683‐1.97‐4.67‐‐‐‐‐‐20DWR Observation Shallow01N04E31H001M37.8957‐121.5652‐4.27‐6.67‐‐‐‐‐‐20DWR Observation Shallow01N04E31H002M37.8896‐121.5705‐5.17‐7.67‐‐‐‐‐‐2011/14/2020Page 12 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DWR Observation Shallow01N04E31K001M37.8871‐121.5744‐3.37‐5.66‐‐ ‐‐ ‐‐20DWR Observation Shallow01N04E31Q001M37.8826‐121.5755‐3.86‐6.66‐‐ ‐‐ ‐‐20DWR Observation Shallow01N04E32D002M37.8957‐121.5652‐5.27‐7.67‐‐ ‐‐ ‐‐20DWR Observation Shallow01N04E32E001M37.8916‐121.5669‐5.17‐7.67‐‐ ‐‐ ‐‐20DWR Observation Shallow01S04E06B001M37.88‐121.57‐‐ ‐237.68‐‐ ‐‐ ‐‐20DWR Observation Shallow01S04E06C001M37.88‐121.574‐‐ ‐236.74‐‐ ‐‐ ‐‐20DWR Observation Shallow01S04E06L001M37.8435‐121.5801‐3.86‐4.66‐‐ ‐‐ ‐‐20DWR Observation Shallow01S04E06L002M37.8743‐121.5771‐3.46‐6.66‐‐ ‐‐ ‐‐20DWR Observation Shallow01S04E06P002M37.85‐121.58‐4.20‐7.00‐‐ ‐‐ ‐‐20DWR Observation Shallow01S04E06Q001M37.8686‐121.5751‐3.86‐6.66‐‐‐‐‐‐20DWRObservation Shallow01S04E06R001M37.86‐121.575‐‐ ‐207.07‐‐‐‐‐‐20DWR Observation Shallow01S04E07A001M37.8644‐121.571‐1.76‐4.67‐‐‐‐‐‐20DWR Observation Shallow01S04E07B001M37.852‐121.57 5.50 3.00‐‐‐‐‐‐20DWR Observation Shallow01S04E07C001M37.8621‐121.5796‐4.55‐7.65‐‐‐‐‐‐20DWR Observation Shallow01S04E08A001M37.8641‐121.5504‐3.57‐5.66‐‐‐‐‐‐20DWR Observation Shallow01S04E08H001M37.8626‐121.5535‐2.97‐5.66‐‐‐‐‐‐20DWR Observation Shallow01S04E08H002M37.8615‐121.5511‐‐ ‐198.86‐‐‐‐‐‐20DWR Observation Shallow01S04E08J001M37.8579‐121.5495‐‐ ‐195.07‐‐‐‐‐‐20DWR Observation Shallow01S04E08K001M37.8591‐121.5552 1.43‐0.67‐‐‐‐‐‐20DWR Observation Shallow01S04E08L001M37.8598‐121.5584‐2.96‐6.66‐‐‐‐‐‐20DWRObservation Shallow01S04E08M001M37.8581‐121.5651‐2.96‐5.66‐‐‐‐‐‐20DWR Observation Shallow01S04E09N001M37.8558‐121.5476‐‐ ‐195.07‐‐‐‐‐‐20DWR Observation Shallow1S/4E 31P 537.797914‐121.580028 60.00 60.00 8‐2352.0037.00 24DWR Observation Shallow378435N1215801W00137.8435‐121.5801‐3.86‐4.66‐‐‐‐‐‐20DWR Observation Shallow378500N1215800W00137.85‐121.58‐4.20‐7.00‐‐‐‐‐‐20DWR Observation Shallow378621N1215796W00137.8621‐121.5796‐4.55‐7.65‐‐‐‐‐‐20DWR Observation Shallow378826N1215755W00137.8826‐121.5755‐3.86‐6.66‐‐‐‐‐‐20DWR Observation Shallow378957N1215652W00137.8957‐121.5652‐4.27‐6.67‐‐‐‐‐‐20DWR Observation Shallow379050N1215730W00137.905‐121.573 4.07‐7.67‐‐‐‐‐‐20DWR‐‐ShallowBD‐137.9035‐121.5752‐6.37 3.11 90‐100‐96.37‐106.37 100DWR‐‐ShallowBD‐237.8836‐121.5791‐6.46 2.83 90‐100‐96.46‐106.46 100DWR‐‐ShallowBD‐337.864705‐121.579748‐7.00‐1.45 90‐100‐97.00‐107.00 100DWR Observation ShallowBS‐437.901133‐121.571309‐2.99‐5.69‐‐‐‐‐‐20DWR Observation ShallowBS‐537.899263‐121.568292‐5.80‐8.00‐‐‐‐‐‐20DWR Observation ShallowBS‐637.896564‐121.567668‐5.80‐8.00‐‐‐‐‐‐20DWR Observation ShallowVD‐237.887444‐121.570556‐6.97‐7.67‐‐‐‐‐‐20DWR Observation ShallowVS‐1037.882414‐121.572674‐3.76‐6.66‐‐‐‐‐‐20DWR Observation ShallowVS‐337.905944‐121.568194‐4.18‐6.69‐‐‐‐‐‐20DWR‐‐Unknown01N02E01F001M37.9627‐121.7081‐‐73.74‐‐‐‐‐‐‐‐DWR‐‐Unknown01N02E03K001M37.9591‐121.7401‐‐117.98‐‐‐‐‐‐‐‐DWR‐‐Unknown01N02E13H001M37.9338‐121.6989‐‐77.86‐‐‐‐‐‐‐‐DWR‐‐Unknown01N02E24M001M37.9157‐121.7127‐‐97.47‐‐‐‐‐‐‐‐11/14/2020Page 13 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DWR‐‐Unknown01N02E24R002M37.9121‐121.6989‐‐94.16‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01N02E25F001M37.9049‐121.7081‐‐114.03‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01N02E25G001M37.9049‐121.7035‐‐105.75‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01N02E26H001M37.9049‐121.7172‐‐115.03‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01N03E06N001M37.9555‐121.6944‐‐60.05‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01N03E06N002M37.9555‐121.6944‐‐60.05‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01N03E09E001M37.9482‐121.6578‐‐37.18‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01N03E13C001M37.9374‐121.5983‐‐3.31‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01N03E18D001M37.9374‐121.6944‐‐70.64‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01N03E18G001M37.9338‐121.6852‐‐64.29‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01N03E25C001M37.9085‐121.5983‐‐2.71‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E26C002M37.9085‐121.6166‐‐4.75‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E27Q003M37.8977‐121.6303‐‐16.18‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E27R001M37.8977‐121.6257‐‐7.85‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E28Q001M37.8977‐121.6486‐‐35.07‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E29Q001M37.8977‐121.6669‐‐57.11‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E30L001M37.9013‐121.6898‐‐94.15‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E30L002M37.9013‐121.6898‐‐94.15‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E30M001M37.9013‐121.6944‐‐99.54‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E31C001M37.894‐121.6898‐‐90.14‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E32C001M37.894‐121.6715‐‐60.46‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E33J001M37.8868‐121.644‐‐30.94‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E34A001M37.894‐121.6257‐‐8.12‐‐‐‐‐‐‐‐DWR‐‐Unknown01N03E35N001M37.8832‐121.6212‐‐6.15‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E02N001M37.8688‐121.6212‐‐12.97‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E02P001M37.8688‐121.6166‐‐8.64‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E03H001M37.876‐121.6257‐‐10.84‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E03M001M37.8741‐121.64‐‐31.58‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E03M002M37.8741‐121.64‐‐31.58‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E03N002M37.8688‐121.6395‐‐32.42‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E03N003M37.8688‐121.6395‐‐32.42‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E03P001M37.8688‐121.6349‐‐26.75‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E03Q001M37.8688‐121.6303‐‐22.89‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E03Q002M37.8688‐121.6303‐‐22.89‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E04Q001M37.8688‐121.6486‐‐39.30‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E09A001M37.8651‐121.644‐‐38.67‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E09A002M37.8651‐121.644‐‐38.67‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E10C001M37.8651‐121.6349‐‐29.29‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E10C002M37.8651‐121.6349‐‐29.29‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E10G001M37.8615‐121.6303‐‐26.34‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E10K001M37.8579‐121.6303‐‐32.41‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E14D001M37.8507‐121.6212‐‐28.62‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E14N001M37.8399‐121.6212‐‐35.30‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E15A001M37.8508‐121.6238‐‐32.03‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E22H001M37.8326‐121.6257‐‐48.56‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E22H002M37.8326‐121.6257‐‐48.56‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E23E001M37.8326‐121.6212‐‐38.77‐‐‐‐‐‐‐‐DWR‐‐Unknown01S03E23J001M37.829‐121.6074‐‐20.65‐‐‐‐‐‐‐‐11/14/2020Page 14 of 15 Well Construction Table‐East Contra Costa Subbasin, Public Supply, Agricultural Irrigation, and DWR WellsOwner/GSA/MonitoringAgencyWell TypeZoneDesginationWell Name Latitude LongitudeTOC Elev.(ft msl)GroundSurfaceElevationScreen Interval (ft bgs)Top ofScreen Interval(ft msl)Bottom ofScreen Interval(ft msl)Well Depth(ft bgs)DWR‐‐Unknown01S03E26A001M37.8218‐121.6074‐‐59.52‐‐ ‐‐ ‐‐ ‐‐DWR‐‐Unknown01S04E09N002M37.8543‐121.548‐‐ ‐5.14‐‐‐‐‐‐‐‐DWR‐‐Unknown01S04E17A001M37.8507‐121.5525‐‐ ‐4.33‐‐‐‐‐‐‐‐DWR‐‐Unknown01S04E17A002M37.8507‐121.5525‐‐ ‐4.33‐‐‐‐‐‐‐‐DWR‐‐Unknown01S04E17C001M37.8507‐121.5617‐‐ ‐1.91‐‐‐‐‐‐‐‐DWR‐‐Unknown01S04E20K001M37.829‐121.5571‐‐2.37‐‐‐‐‐‐‐‐DWR‐‐Unknown02N02E20A001M38.0096‐121.7721‐‐40.19‐‐‐‐‐‐‐‐DWR‐‐Unknown02N02E36M001M37.9735‐121.7127‐‐77.65‐‐‐‐‐‐‐‐DWR‐‐Unknown02N03E10D001M38.0385‐121.6395‐‐6.65‐‐‐‐‐‐‐‐DWR‐‐Unknown02N03E15Q001M38.0133‐121.6303‐‐5.17‐‐‐‐‐‐‐‐DWR‐‐Unknown02N03E29M001M37.988‐121.6761‐‐14.23‐‐‐‐‐‐‐‐Abbreviations:DWR‐ Department of Water Resources BBID‐ Byron Bethany Irrigation Distmsl‐ mean sea levelECCID‐ East Contra Costa Irrigation Districtbgs‐ below ground surface TOC‐ Top of Casingft‐ feetDDW‐ Division of Drinking WaterGSA‐ Groundwater Sustainability AgencyDWD‐ Diablo Water District11/14/2020Page 15 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Shallow T0601300803-STMW-3 38.0113647 -121.8164043 18.19 -77.29 ------20 Geotracker --Unknown SL0601327206-EW-1 38.0124906 -121.8262758 17.09 -67.49 -------- Geotracker Monitoring Unknown SL0601327206-MW-1 38.0124851 -121.8262136 16.99 -67.49 -------- Geotracker Monitoring Unknown SL0601327206-MW-2 38.0124981 -121.826324 17.45 -67.49 -------- Geotracker Monitoring Unknown SL0601346154-94MW-1 37.99763297 -121.7598206 70.63 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94MW-12 37.997267 -121.7601833 53.87 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94MW-14 37.9973253 -121.7587909 53.71 -97.70 -------- Geotracker Monitoring Unknown SL0601346154-94MW-18 37.9973406 -121.7591286 56.44 -97.70 -------- Geotracker Monitoring Unknown SL0601346154-94MW-19 37.9970033 -121.7591763 54.70 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94MW-2 37.99742985 -121.7595953 70.30 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94MW-22 37.9977806 -121.7590815 81.87 -97.70 -------- Geotracker Monitoring Unknown SL0601346154-94MW-23 37.9977759 -121.7597224 72.46 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94MW-25 37.99752224 -121.7596478 70.36 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94MW-3 37.99737148 -121.7598189 70.24 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94MW-4 37.9976908 -121.760264 67.39 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94MW-5 37.9983647 -121.7599193 74.00 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94MW-6 37.99771421 -121.7591362 80.62 -97.70 -------- Geotracker Monitoring Unknown SL0601346154-94MW-7 37.9977122 -121.7590266 82.47 -97.70 -------- Geotracker Monitoring Unknown SL0601346154-94MW-8 37.9974352 -121.7595547 71.06 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94MW-9 37.9981846 -121.7605201 73.52 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94SP-2 37.99748208 -121.7596956 70.35 -100.38 -------- Geotracker Monitoring Unknown SL0601346154-94SP-4 37.99748348 -121.7596706 70.68 -100.38 -------- Geotracker Monitoring Unknown SL0601394831-MW-1 38.00979466 -121.7501967 21.78 -103.29 -------- Geotracker Monitoring Unknown SL0601394831-MW-2 38.00966682 -121.7500914 22.58 -103.29 -------- Geotracker Monitoring Unknown SL0601394831-MW-3 38.00952959 -121.7502572 23.00 -103.29 -------- Geotracker Monitoring Unknown SL0601394831-MW-4 38.0097062 -121.750356 22.59 -103.29 -------- Geotracker Monitoring Unknown SL186102968-7EW-1 37.99799564 -121.7092015 20.39 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7EW-2 37.99800735 -121.7093709 20.34 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7EW-3 37.9980815 -121.7093025 22.68 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7EW-4 37.99807566 -121.7094744 20.19 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7EW-5 37.99806122 -121.7091587 22.51 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7EW-6 37.99806424 -121.7093743 22.44 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7EW-7 37.99802921 -121.7090872 22.59 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-1 37.9981523 -121.7092386 21.51 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-10 37.9978009 -121.7091346 24.04 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-11 37.9978089 -121.709496 26.48 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-12 37.9979889 -121.7098298 19.03 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-13 37.9981346 -121.709828 17.62 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-14 37.9980541 -121.7095267 20.31 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-2 37.998027 -121.7090709 22.36 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-3 37.9979121 -121.7091968 23.17 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-4 37.9979891 -121.7091461 22.94 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-5 37.9980537 -121.7092528 22.55 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-6 37.9981087 -121.7093618 21.97 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-7 37.9982924 -121.7092256 22.98 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-8 37.9981008 -121.70883 23.79 -98.45 -------- Geotracker Monitoring Unknown SL186102968-7MW-9 37.9977945 -121.7088098 22.99 -98.45 -------- Geotracker --Unknown SL20210828-903B1 38.02213191 -121.8415902 12.56 -59.40 -------- Geotracker Monitoring Unknown SL205032990-GCC-1 38.0154259 -121.7733017 27.74 -111.04 -------- Geotracker Monitoring Unknown SL205032990-GCC-2 38.0154017 -121.7733006 27.80 -111.04 -------- Geotracker Monitoring Unknown SL205032990-GCC-3 38.0153842 -121.7732943 27.98 -111.04 -------- Geotracker Monitoring Unknown SL205032990-GCC-4 38.0153836 -121.773275 28.14 -111.04 -------- Page 1 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker --Unknown SL205032990-GPG-1 38.0151254 -121.7857635 26.28 -106.31 -------- Geotracker --Unknown SL205032990-GPG-2 38.0151314 -121.7857251 26.44 -106.31 -------- Geotracker --Unknown SL205032990-W-01 38.0124701 -121.7782997 33.80 -108.58 -------- Geotracker --Unknown SL205032990-W-02 38.0137724 -121.7800415 29.37 -109.18 -------- Geotracker --Unknown SL205032990-W-03 38.0143072 -121.7798501 19.98 -109.18 -------- Geotracker --Unknown SL205032990-W-04 38.0131714 -121.7791378 35.07 -109.18 -------- Geotracker --Unknown SL205032990-W-05 38.0135223 -121.7795815 36.84 -109.18 -------- Geotracker --Unknown SL205032990-W-06 38.0136725 -121.7797346 33.46 -109.18 -------- Geotracker --Unknown SL205032990-W-07 38.0135821 -121.7803374 29.88 -109.18 -------- Geotracker --Unknown SL205032990-W-08 38.0135895 -121.7802884 32.84 -109.18 -------- Geotracker --Unknown SL205032990-W-09 38.0141134 -121.7801852 16.84 -109.18 -------- Geotracker --Unknown SL205032990-W-10 38.0136944 -121.7796301 35.70 -109.18 -------- Geotracker --Unknown SL205032990-W-11 38.0141616 -121.7801488 16.56 -109.18 -------- Geotracker --Unknown SL205032990-W-12 38.0148054 -121.7804337 21.19 -109.18 -------- Geotracker --Unknown SL205032990-W-13 38.0140557 -121.7806932 19.99 -106.31 -------- Geotracker --Unknown SL205032990-W-14 38.0148174 -121.7778223 11.16 -109.18 -------- Geotracker --Unknown SL205032990-W-15 38.013924 -121.7782276 17.78 -109.18 -------- Geotracker --Unknown SL205032990-W-16 38.0145546 -121.7796335 21.32 -109.18 -------- Geotracker --Unknown SL205032990-W-17 38.0147691 -121.7803996 20.48 -109.18 -------- Geotracker --Unknown SL205032990-W-18 38.0147754 -121.7804429 21.36 -109.18 -------- Geotracker --Unknown SL205032990-W-19 38.0141354 -121.7802108 15.83 -109.18 -------- Geotracker --Unknown SL205032990-W-20 38.0148596 -121.7778279 11.96 -109.18 -------- Geotracker --Unknown SL205032990-W-21 38.0140728 -121.7806637 18.96 -106.31 -------- Geotracker --Unknown SL205032990-W-22 38.0125118 -121.7783151 34.52 -109.18 -------- Geotracker --Unknown SL205032990-W-23 38.0139487 -121.7782341 17.52 -109.18 -------- Geotracker --Unknown SL205032990-W-24 38.014529 -121.7796147 21.60 -109.18 -------- Geotracker --Unknown SL205032990-W-25 38.0125359 -121.7783366 35.16 -109.18 -------- Geotracker --Unknown SL205032990-W-26 38.0125417 -121.7797532 39.17 -109.18 -------- Geotracker --Unknown SL205032990-W-27 38.0146731 -121.7787581 10.21 -109.18 -------- Geotracker --Unknown SL205032990-W-28 38.0147021 -121.7787535 9.53 -109.18 -------- Geotracker --Unknown SL205032990-W-29 38.0148319 -121.7778483 11.28 -109.18 -------- Geotracker --Unknown SL205032990-W-30 38.012557 -121.7797589 38.45 -109.18 -------- Geotracker --Unknown SL205032990-W-31 38.0139152 -121.780437 19.42 -109.18 -------- Geotracker --Unknown SL205032990-W-32 38.0141668 -121.780072 18.22 -109.18 -------- Geotracker --Unknown SL205032990-W-33 38.0142447 -121.7799241 19.05 -109.18 -------- Geotracker --Unknown SL205032990-W-34 38.0138037 -121.7796211 22.05 -109.18 -------- Geotracker --Unknown SL205032990-W-35 38.0141958 -121.7793729 22.25 -109.18 -------- Geotracker --Unknown SL205032990-W-36 38.0141791 -121.7793647 22.45 -109.18 -------- Geotracker --Unknown SL205032990-W-37 38.0144931 -121.7786015 11.08 -109.18 -------- Geotracker --Unknown SL205032990-W-38 38.0145226 -121.7786021 11.42 -109.18 -------- Geotracker --Unknown SL205032990-W-39 38.0144936 -121.7782188 13.40 -109.18 -------- Geotracker --Unknown SL205032990-W-40 38.0145758 -121.7780404 13.86 -109.18 -------- Geotracker Monitoring Unknown SL205092993-MW-11A 37.9978322 -121.843182 110.37 -25.74 -------- Geotracker Monitoring Unknown SL205092993-MW-12A 37.9978602 -121.8425416 108.65 -33.13 -------- Geotracker Monitoring Unknown SL205092993-MW-14A 37.9983182 -121.843986 107.54 -25.74 -------- Geotracker Monitoring Unknown SL205092993-MW-17A 37.9975032 -121.8416801 109.02 -33.13 -------- Geotracker Monitoring Unknown SL205092993-MW-18A 37.9980477 -121.8451401 110.59 -25.74 -------- Geotracker Monitoring Unknown SL205092993-MW-19A 37.9976307 -121.8442498 111.13 -25.74 -------- Geotracker Monitoring Unknown SL205092993-MW-20B 37.9977877 -121.8437805 110.28 -25.74 -------- Geotracker Monitoring Unknown SL205092993-MW-21A 37.9977883 -121.8437416 110.13 -25.74 -------- Geotracker Monitoring Unknown SL205092993-MW-3A 37.9977693 -121.8437697 111.75 -25.74 -------- Geotracker Monitoring Unknown SL205092993-MW-5A 37.9978408 -121.8435181 109.98 -25.74 -------- Page 2 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown SL205092993-MW-5B 37.9977964 -121.843548 109.90 -25.74 -------- Geotracker Monitoring Unknown SL205092993-MW-6A 37.9979223 -121.8433416 109.56 -25.74 -------- Geotracker Monitoring Unknown SL205092993-MW-8A 37.9982209 -121.843463 108.88 -25.74 -------- Geotracker Monitoring Unknown SL205383009-ORC-7 37.9251716 -121.7233168 103.65 -128.93 -------- Geotracker Monitoring Unknown SL205383009-ORC-8 37.9250927 -121.7232733 102.80 -128.93 -------- Geotracker Monitoring Unknown SL205383009-ORC-9A 37.9250193 -121.7232463 102.75 -128.93 -------- Geotracker Monitoring Unknown SL205383009-SB-56 37.9250435 -121.7235089 102.06 -128.93 -------- Geotracker Monitoring Unknown SL205383009-SB-57 37.925157 -121.7228611 103.32 -128.93 -------- Geotracker Monitoring Unknown SL205383009-SB-58 37.9251558 -121.7228858 103.32 -128.93 -------- Geotracker Monitoring Unknown SL205383009-SB-77 37.9245299 -121.7227896 100.59 -128.93 -------- Geotracker Monitoring Unknown SL205383009-SB-78 37.9251789 -121.7223146 101.37 -128.93 -------- Geotracker Monitoring Unknown SL205383009-SB-79 37.9255381 -121.7220427 102.01 -128.93 -------- Geotracker Monitoring Unknown SL205383009-SB-81A 37.9249892 -121.7234247 103.41 -128.93 -------- Geotracker Monitoring Unknown SL205383009-SB-82A 37.9247969 -121.7231043 102.26 -128.93 -------- Geotracker Monitoring Unknown SL205383009-SB-83A 37.9250297 -121.7228089 102.34 -128.93 -------- Geotracker Monitoring Unknown T0601300676-MW-11 38.0059117 -121.8337381 49.45 51.86 -------- Geotracker Monitoring Unknown T0601300676-MW-16A 38.006066 -121.8341603 55.09 53.14 -------- Geotracker Monitoring Unknown T0601300676-MW-16B 38.0060518 -121.8341719 55.31 53.14 -------- Geotracker Monitoring Unknown T0601300676-MW-16C 38.0060439 -121.8341918 55.19 53.14 -------- Geotracker Monitoring Unknown T0601300676-MW-17 38.0061868 -121.8343704 54.94 52.82 -------- Geotracker Monitoring Unknown T0601300676-MW-22 38.0068195 -121.8341197 50.29 49.89 -------- Geotracker Monitoring Unknown T0601300676-MW-22C 38.0068368 -121.8340992 50.32 48.79 -------- Geotracker Monitoring Unknown T0601300676-MW-23 38.0063707 -121.8349983 55.21 51.29 -------- Geotracker Monitoring Unknown T0601300676-MW-24 38.0066495 -121.8346758 51.88 50.51 -------- Geotracker Monitoring Unknown T0601300676-MW-25 38.0064355 -121.8340507 51.54 51.85 -------- Geotracker Monitoring Unknown T0601300676-MW-25B 38.0064183 -121.8340456 51.63 51.85 -------- Geotracker Monitoring Unknown T0601300676-MW-26 38.0061679 -121.8343722 54.95 53.13 -------- Geotracker Monitoring Unknown T0601300676-MW-26B 38.0061656 -121.8343524 55.05 53.13 -------- Geotracker Monitoring Unknown T0601300676-MW-28 38.006751 -121.8338309 49.92 49.60 -------- Geotracker Monitoring Unknown T0601300676-MW-28C 38.0067594 -121.8338183 49.81 49.60 -------- Geotracker Monitoring Unknown T0601300676-MW-29 38.0058874 -121.8334668 50.35 50.93 -------- Geotracker Monitoring Unknown T0601300676-MW-30A 38.0063123 -121.833775 50.73 51.45 -------- Geotracker Monitoring Unknown T0601300676-MW-31A 38.0061084 -121.8338525 52.54 52.14 -------- Geotracker Monitoring Unknown T0601300676-MW-32D 38.006267 -121.8341172 52.78 52.47 -------- Geotracker Monitoring Unknown T0601300676-MW-5A 38.0062378 -121.8342137 54.85 52.64 -------- Geotracker Monitoring Unknown T0601300676-MW-5B 38.0062447 -121.8341948 54.51 52.64 -------- Geotracker Monitoring Unknown T0601300676-MW-5C 38.0062516 -121.8341759 54.18 52.64 -------- Geotracker Monitoring Unknown T0601300676-MW-6 38.0058298 -121.8342566 52.64 53.40 -------- Geotracker --Unknown T0601300676-SW-1 38.0061866 -121.8339985 53.15 -46.47 -------- Geotracker --Unknown T0601300676-SW-2 38.0060755 -121.8338679 52.98 -46.47 -------- Geotracker --Unknown T0601300744-W-1 37.9368842 -121.6951473 67.54 71.30 -------- Geotracker --Unknown T0601300744-W-2 37.9366645 -121.6952831 67.95 71.37 -------- Geotracker --Unknown T0601300744-W-3 37.9364996 -121.6949322 68.34 71.63 -------- Geotracker --Unknown T0601300744-W-4 37.9365669 -121.6946313 67.96 71.63 -------- Geotracker --Unknown T0601300744-W-5B 37.9369442 -121.6949261 68.95 71.08 -------- Geotracker --Unknown T0601300744-W-6 37.9371071 -121.6952278 67.49 71.04 -------- Geotracker --Unknown T0601300744-W-7B 37.9366314 -121.6955414 69.06 71.63 -------- Geotracker --Unknown T0601300744-W-8 37.9363032 -121.6950244 68.67 71.96 -------- Geotracker --Unknown T0601300744-W-9 37.9365957 -121.6948036 67.70 71.63 -------- Geotracker Monitoring Unknown T0601300747-MW-1 38.0152337 -121.8135181 28.00 -79.94 -------- Geotracker Monitoring Unknown T0601300747-MW-2 38.0153519 -121.8136577 22.92 -79.94 -------- Geotracker Monitoring Unknown T0601300747-MW-3 38.0153621 -121.8135367 28.05 -79.94 -------- Page 3 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown T0601300747-MW-4 38.015518 -121.8135464 27.45 -79.94 -------- Geotracker Monitoring Unknown T0601300747-MW-5 38.0149805 -121.8137153 27.41 -79.94 -------- Geotracker Monitoring Unknown T0601300747-MW-6 38.0153595 -121.8139196 26.55 -79.94 -------- Geotracker Monitoring Unknown T0601300747-MW-7 38.0157416 -121.8131942 28.26 -79.94 -------- Geotracker Monitoring Unknown T0601300747-MW-8 38.0157168 -121.8138179 28.16 -79.94 -------- Geotracker Monitoring Unknown T0601300747-MW-9 38.0153718 -121.8132026 26.88 -79.94 -------- Geotracker Monitoring Unknown T0601300747-PZ-01 38.0153102 -121.8135375 28.35 -79.94 -------- Geotracker Monitoring Unknown T0601300747-PZ-02 38.0153363 -121.8135592 28.26 -79.94 -------- Geotracker Monitoring Unknown T0601300747-PZ-03 38.015332 -121.8135202 28.05 -79.94 -------- Geotracker --Unknown T0601300756-EW100 37.9985656 -121.822348 34.72 -53.26 -------- Geotracker --Unknown T0601300756-EW101 37.9988293 -121.8222826 36.08 -53.26 -------- Geotracker Monitoring Unknown T0601300756-MW-1 37.9983089 -121.822326 34.49 -53.26 -------- Geotracker Monitoring Unknown T0601300756-MW-10L 37.99910075 -121.8221644 41.26 -60.37 -------- Geotracker Monitoring Unknown T0601300756-MW-10U 37.99911189 -121.822006 35.89 -60.37 -------- Geotracker Monitoring Unknown T0601300756-MW-11L 37.99889936 -121.822009 39.63 -60.37 -------- Geotracker Monitoring Unknown T0601300756-MW-12L 37.99861509 -121.8222438 36.83 -53.26 -------- Geotracker Monitoring Unknown T0601300756-MW-2 37.99856964 -121.8222751 37.06 -53.26 -------- Geotracker Monitoring Unknown T0601300756-MW-3 37.9987792 -121.8223128 37.10 -53.26 -------- Geotracker Monitoring Unknown T0601300756-MW-4 37.998635 -121.822323 34.96 -53.26 -------- Geotracker Monitoring Unknown T0601300756-MW-5 37.9984517 -121.8223656 35.01 -53.26 -------- Geotracker Monitoring Unknown T0601300756-MW-6A 37.99900008 -121.8220995 39.89 -60.37 -------- Geotracker Monitoring Unknown T0601300756-MW-7A 37.99911244 -121.8222631 41.29 -53.26 -------- Geotracker Monitoring Unknown T0601300756-MW-8U 37.99833577 -121.8224897 38.16 -53.26 -------- Geotracker Monitoring Unknown T0601300756-MW-9U 37.99908525 -121.8221338 40.57 -60.37 -------- Geotracker Monitoring Unknown T0601300764-MW-1 38.0156887 -121.8194631 15.09 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-10 38.0156602 -121.8196409 14.65 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-11 38.0156238 -121.819455 15.28 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-12 38.0155174 -121.8192871 15.09 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-13S 38.0158126 -121.8196397 14.94 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-14D 38.0158058 -121.8196407 14.73 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-15 38.0154191 -121.8199898 15.03 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-16 38.0157683 -121.8194752 14.96 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-17 38.0157633 -121.8195667 14.77 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-2 38.0157465 -121.8194856 14.94 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-3 38.0157422 -121.819522 14.73 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-4 38.0156534 -121.8194282 15.03 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-5 38.0155878 -121.8194967 15.53 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-6 38.0159386 -121.8195728 13.36 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-7 38.016145 -121.8195537 12.31 -76.63 -------- Geotracker Monitoring Unknown T0601300764-MW-8 38.015973 -121.8198354 12.83 -73.77 -------- Geotracker Monitoring Unknown T0601300764-MW-9 38.0154291 -121.8195113 15.27 -73.77 -------- Geotracker Monitoring Unknown T0601300764-SP-1 38.0157792 -121.8195718 15.26 -73.77 -------- Geotracker Monitoring Unknown T0601300764-SP-10 38.0157557 -121.8194742 15.44 -73.77 -------- Geotracker Monitoring Unknown T0601300764-SP-2 38.0157798 -121.8195533 15.37 -73.77 -------- Geotracker Monitoring Unknown T0601300764-SP-3 38.0157789 -121.8195263 15.38 -73.77 -------- Geotracker Monitoring Unknown T0601300764-SP-4 38.0157789 -121.8194934 15.40 -73.77 -------- Geotracker Monitoring Unknown T0601300764-SP-5 38.0157796 -121.8194702 15.38 -73.77 -------- Geotracker Monitoring Unknown T0601300764-SP-6 38.0157589 -121.8195716 15.26 -73.77 -------- Geotracker Monitoring Unknown T0601300764-SP-7 38.0157542 -121.8195417 15.32 -73.77 -------- Geotracker Monitoring Unknown T0601300764-SP-8 38.0157552 -121.8195261 15.39 -73.77 -------- Geotracker Monitoring Unknown T0601300764-SP-9 38.0157567 -121.8194951 15.42 -73.77 -------- Geotracker Monitoring Unknown T0601300766-IW10 37.9329167 -121.6936652 76.77 -104.59 -------- Page 4 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown T0601300766-IW9 37.9329025 -121.6936893 77.31 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW1 37.9327737 -121.6939078 78.01 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW2 37.9328761 -121.6939949 78.00 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW3 37.9330462 -121.6937609 77.07 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW4 37.9329572 -121.6936399 76.75 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW5 37.932885 -121.6936264 76.80 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW6A 37.9330193 -121.6939911 76.97 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW6B 37.9330156 -121.6939972 77.01 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW7A 37.9329946 -121.693405 76.29 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW7B 37.933 -121.6934076 76.27 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW8A 37.9327127 -121.6932717 75.64 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW8B 37.9327176 -121.6932757 75.48 -104.59 -------- Geotracker Monitoring Unknown T0601300766-MW8C 37.9327231 -121.6932819 75.69 -104.59 -------- Geotracker Monitoring Unknown T0601300768-MW-1 38.0027038 -121.8391442 77.59 -35.76 -------- Geotracker Monitoring Unknown T0601300768-MW-1R 38.0026908 -121.8391612 77.71 -35.76 -------- Geotracker Monitoring Unknown T0601300768-MW-2 38.0025267 -121.8394175 79.40 -35.76 -------- Geotracker Monitoring Unknown T0601300768-MW-3 38.0028146 -121.8392837 78.17 -35.76 -------- Geotracker Monitoring Unknown T0601300768-MW-3R 38.0028246 -121.8393014 78.05 -35.76 -------- Geotracker Monitoring Unknown T0601300768-MW-4 38.0027292 -121.8394187 78.98 -35.76 -------- Geotracker Monitoring Unknown T0601300768-MW-6 38.002802 -121.8390101 77.05 -35.76 -------- Geotracker Monitoring Unknown T0601300768-MW-7 38.0026041 -121.8390904 78.27 -35.76 -------- Geotracker Monitoring Unknown T0601300768-SVE-1 38.0026568 -121.8391433 77.82 -35.76 -------- Geotracker Monitoring Unknown T0601300768-SVE-2 38.002691 -121.8391301 77.28 -35.76 -------- Geotracker Monitoring Unknown T0601300768-SVE-3 38.0026878 -121.8391135 77.20 -35.76 -------- Geotracker Monitoring Unknown T0601300768-SVE-4 38.0025936 -121.8391033 78.40 -35.76 -------- Geotracker Monitoring Unknown T0601300768-SVE-5 38.0025832 -121.8391162 78.31 -35.76 -------- Geotracker Monitoring Unknown T0601300769-MW-1 38.0115649 -121.8239635 16.06 -63.74 -------- Geotracker Monitoring Unknown T0601300769-MW-2 38.0115564 -121.8238235 16.09 -63.74 -------- Geotracker Monitoring Unknown T0601300769-MW-3 38.011849 -121.8239908 15.90 -67.49 -------- Geotracker Monitoring Unknown T0601300769-P-1 38.0115751 -121.8239662 16.29 -63.74 -------- Geotracker Monitoring Unknown T0601300769-P-2 38.0115773 -121.8239467 16.12 -63.74 -------- Geotracker Monitoring Unknown T0601300769-P-3 38.0116095 -121.8239794 16.78 -63.74 -------- Geotracker Monitoring Unknown T0601300772-AS-10 38.0062277 -121.8054718 37.82 -85.29 -------- Geotracker Monitoring Unknown T0601300772-AS-11 38.0062759 -121.8054357 37.14 -85.29 -------- Geotracker Monitoring Unknown T0601300772-AS-12 38.0062651 -121.8054954 37.60 -85.29 -------- Geotracker Monitoring Unknown T0601300772-AS-2 38.0061569 -121.8058571 38.32 -85.29 -------- Geotracker Monitoring Unknown T0601300772-AS-3 38.0060913 -121.8058056 38.55 -85.29 -------- Geotracker Monitoring Unknown T0601300772-AS-4 38.0061433 -121.8057191 39.23 -85.29 -------- Geotracker Monitoring Unknown T0601300772-AS-5 38.0061009 -121.8056617 39.15 -85.29 -------- Geotracker Monitoring Unknown T0601300772-AS-6 38.0061827 -121.8056382 38.78 -85.29 -------- Geotracker Monitoring Unknown T0601300772-AS-7 38.0060826 -121.8054862 38.12 -85.29 -------- Geotracker Monitoring Unknown T0601300772-AS-8 38.0060316 -121.8054712 38.28 -85.29 -------- Geotracker Monitoring Unknown T0601300772-AS-9 38.0061043 -121.8054369 38.34 -85.29 -------- Geotracker Monitoring Unknown T0601300772-MW-1 38.00625498 -121.8058466 35.39 38.22 -------- Geotracker Monitoring Unknown T0601300772-MW-10 38.00620952 -121.8061775 36.00 38.25 -------- Geotracker Monitoring Unknown T0601300772-MW-11 38.0056385 -121.8053273 39.18 -85.29 -------- Geotracker Monitoring Unknown T0601300772-MW-12 38.00596199 -121.8050542 36.76 38.65 -------- Geotracker Monitoring Unknown T0601300772-MW-13 38.00625922 -121.8050555 35.58 37.83 -------- Geotracker Monitoring Unknown T0601300772-MW-14 38.00643977 -121.8053422 33.68 37.78 -------- Geotracker Monitoring Unknown T0601300772-MW-15 38.00641723 -121.805002 33.33 37.42 -------- Geotracker Monitoring Unknown T0601300772-MW-16 38.00717471 -121.8047707 32.15 36.37 -------- Geotracker Monitoring Unknown T0601300772-MW-17 38.00716902 -121.8047858 32.33 36.37 -------- Page 5 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown T0601300772-MW-2 38.006287 -121.8056117 35.67 38.25 -------- Geotracker Monitoring Unknown T0601300772-MW-3 38.00613724 -121.8056524 36.94 38.85 -------- Geotracker Monitoring Unknown T0601300772-MW-4 38.00612698 -121.8058486 35.85 38.77 -------- Geotracker Monitoring Unknown T0601300772-MW-5 38.00647037 -121.805826 35.23 37.90 -------- Geotracker Monitoring Unknown T0601300772-MW-6 38.00645471 -121.8055512 34.69 37.92 -------- Geotracker Monitoring Unknown T0601300772-MW-7 38.00624756 -121.8054469 35.75 38.48 -------- Geotracker Monitoring Unknown T0601300772-MW-8 38.00606136 -121.8054427 35.98 38.90 -------- Geotracker Monitoring Unknown T0601300772-MW-9 38.00585883 -121.8057234 36.80 39.43 -------- Geotracker Monitoring Unknown T0601300772-RW-1 38.00628235 -121.8054523 --38.16 -------- Geotracker Monitoring Unknown T0601300772-SVE-10 38.0061222 -121.8057912 38.37 -85.29 -------- Geotracker Monitoring Unknown T0601300772-SVE-2 38.0061409 -121.8056135 38.75 -85.29 -------- Geotracker Monitoring Unknown T0601300772-SVE-3 38.0062802 -121.805406 37.71 -85.29 -------- Geotracker Monitoring Unknown T0601300772-SVE-4 38.0062428 -121.8054153 38.19 -85.29 -------- Geotracker Monitoring Unknown T0601300772-SVE-5 38.0062057 -121.8054183 38.30 -85.29 -------- Geotracker Monitoring Unknown T0601300772-SVE-6 38.0061408 -121.8054135 38.24 -85.29 -------- Geotracker Monitoring Unknown T0601300772-SVE-7 38.0060834 -121.8054199 38.22 -85.29 -------- Geotracker Monitoring Unknown T0601300772-SVE-8 38.0060305 -121.8054248 38.25 -85.29 -------- Geotracker Monitoring Unknown T0601300772-SVE-9 38.0061543 -121.8058248 38.04 -85.29 -------- Geotracker Monitoring Unknown T0601300772-VE-1 38.0061417 -121.8056109 --38.80 -------- Geotracker Monitoring Unknown T0601300772-VE-2 38.00625686 -121.8056127 --38.25 -------- Geotracker Monitoring Unknown T0601300775-B-53 37.9399721 -121.6224433 --6.85 -------- Geotracker Monitoring Unknown T0601300775-B-54 37.9399412 -121.6221982 --6.85 -------- Geotracker Monitoring Unknown T0601300775-B-55 37.9399259 -121.6220835 --6.82 -------- Geotracker Monitoring Unknown T0601300775-B-56 37.9399323 -121.6219097 --6.82 -------- Geotracker Monitoring Unknown T0601300775-B-57 37.9399159 -121.6217167 --6.86 -------- Geotracker --Unknown T0601300775-EW-1 37.93957 -121.6230904 15.91 -170.96 -------- Geotracker --Unknown T0601300775-EW-2 37.9395742 -121.6228656 16.48 -170.96 -------- Geotracker --Unknown T0601300775-EW-3 37.9396656 -121.6229469 16.26 -170.96 -------- Geotracker Monitoring Unknown T0601300775-MW-1 37.9395163 -121.6233194 16.74 -170.96 -------- Geotracker Monitoring Unknown T0601300775-MW-2 37.93943 -121.6231362 16.35 -170.96 -------- Geotracker Monitoring Unknown T0601300775-MW-3 37.939209 -121.6231662 15.11 -170.96 -------- Geotracker Monitoring Unknown T0601300775-MW-4 37.9394298 -121.6228674 15.75 -170.96 -------- Geotracker Monitoring Unknown T0601300775-MW-5 37.9397156 -121.6223688 15.24 -170.96 -------- Geotracker Monitoring Unknown T0601300775-MW-6 37.9399769 -121.6232528 15.96 -170.96 -------- Geotracker --Unknown T0601300776-CES-15 38.0153331 -121.80578 9.54 -91.08 -------- Geotracker --Unknown T0601300776-CES-16 38.0154219 -121.8056033 7.63 -91.08 -------- Geotracker --Unknown T0601300776-CES-17 38.0153086 -121.8055106 6.68 -91.08 -------- Geotracker --Unknown T0601300776-CES-18 38.0152066 -121.8056389 10.29 -91.08 -------- Geotracker --Unknown T0601300776-CES-4 38.0153155 -121.8056438 10.24 -91.08 -------- Geotracker Monitoring Unknown T0601300776-KMW-10 38.0143818 -121.803181 9.72 -91.08 -------- Geotracker Monitoring Unknown T0601300776-KMW-11 38.0151455 -121.8055429 9.92 -91.08 -------- Geotracker Monitoring Unknown T0601300776-KMW-8 38.0159326 -121.8057552 12.38 -91.08 -------- Geotracker Monitoring Unknown T0601300776-KMW-9 38.0149425 -121.803307 7.49 -91.08 -------- Geotracker --Unknown T0601300776-KSG-7 38.0147418 -121.8044234 9.72 -91.08 -------- Geotracker --Unknown T0601300776-KSG-8 38.0154645 -121.8042903 9.13 -91.08 -------- Geotracker Monitoring Unknown T0601300776-MW-12 38.0154589 -121.8038753 7.07 -91.08 -------- Geotracker Monitoring Unknown T0601300776-MW-2 38.015543 -121.8047278 9.13 -91.08 -------- Geotracker Monitoring Unknown T0601300776-MW-3 38.0154062 -121.8055011 10.15 -91.08 -------- Geotracker Monitoring Unknown T0601300776-MW-4 38.0146512 -121.8057372 19.08 -91.08 -------- Geotracker Monitoring Unknown T0601300776-MW-5 38.0156693 -121.8054338 10.50 -91.08 -------- Geotracker Monitoring Unknown T0601300776-MW-6 38.0151593 -121.8041467 9.13 -91.08 -------- Geotracker Monitoring Unknown T0601300776-MW-7A 38.0162706 -121.8048532 9.51 -92.58 -------- Page 6 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker --Unknown T0601300776-SG-1 38.0149875 -121.8054495 11.85 -91.08 -------- Geotracker --Unknown T0601300776-SG-10 38.0151492 -121.8030763 7.13 -91.08 -------- Geotracker --Unknown T0601300776-SG-2 38.0155612 -121.8047643 9.82 -91.08 -------- Geotracker --Unknown T0601300776-SG-3 38.0149324 -121.8041339 9.18 -91.08 -------- Geotracker --Unknown T0601300776-SG-6A 38.0162318 -121.8044948 10.09 -91.08 -------- Geotracker Monitoring Unknown T0601300780-MW-1 38.0089854 -121.8315545 41.48 -57.25 -------- Geotracker Monitoring Unknown T0601300780-MW-10 38.0092285 -121.8313757 40.58 -57.25 -------- Geotracker Monitoring Unknown T0601300780-MW-11 38.0090482 -121.8312883 38.36 -57.25 -------- Geotracker Monitoring Unknown T0601300780-MW-12 38.0096328 -121.8321013 38.63 -57.25 -------- Geotracker Monitoring Unknown T0601300780-MW-2 38.0089225 -121.8315566 41.23 -57.25 -------- Geotracker Monitoring Unknown T0601300780-MW-3 38.0089878 -121.8316272 41.68 -57.25 -------- Geotracker Monitoring Unknown T0601300780-MW-4 38.0089695 -121.8317001 41.73 -57.25 -------- Geotracker Monitoring Unknown T0601300780-MW-5 38.0089797 -121.8313929 39.68 -57.25 -------- Geotracker Monitoring Unknown T0601300780-MW-6 38.0088569 -121.8314387 40.99 -57.25 -------- Geotracker Monitoring Unknown T0601300780-MW-8 38.0091061 -121.8316479 42.31 -57.25 -------- Geotracker Monitoring Unknown T0601300780-MW-9 38.0091814 -121.8315869 41.85 -57.25 -------- Geotracker Monitoring Unknown T0601300781-DW-1A 38.0117949 -121.8058731 17.85 -88.75 -------- Geotracker Monitoring Unknown T0601300781-DW-1B 38.0117959 -121.8058574 17.66 -88.75 -------- Geotracker Monitoring Unknown T0601300781-DW-2A 38.0119113 -121.8058574 17.56 -88.75 -------- Geotracker Monitoring Unknown T0601300781-DW-2B 38.011911 -121.8058501 17.50 -88.75 -------- Geotracker Monitoring Unknown T0601300781-MW-1 38.0118321 -121.8058495 17.67 -88.75 -------- Geotracker Monitoring Unknown T0601300781-MW-2 38.011746 -121.8059614 17.57 -88.75 -------- Geotracker Monitoring Unknown T0601300781-MW-3 38.0119104 -121.8057926 17.81 -88.75 -------- Geotracker Monitoring Unknown T0601300781-MW-4 38.0120298 -121.8058484 16.26 -88.75 -------- Geotracker Monitoring Unknown T0601300781-MW-5 38.0119314 -121.8055469 17.76 -88.75 -------- Geotracker Monitoring Unknown T0601300781-MW-6 38.0120741 -121.8053981 17.15 -88.75 -------- Geotracker Monitoring Unknown T0601300781-MW-7 38.0121171 -121.8056318 16.90 -91.08 -------- Geotracker Monitoring Unknown T0601300781-MW-8 38.0118236 -121.8059642 17.33 -88.75 -------- Geotracker Monitoring Unknown T0601300781-MW-9 38.0117861 -121.805894 17.89 -88.75 -------- Geotracker Monitoring Unknown T0601300782-EW-1 37.9995969 -121.8055167 46.68 47.17 -------- Geotracker Monitoring Unknown T0601300782-EW-2 37.9995983 -121.8053608 45.97 46.35 -------- Geotracker Monitoring Unknown T0601300782-EW-3 37.9995676 -121.8054139 45.84 46.35 -------- Geotracker Monitoring Unknown T0601300782-MW-1 37.9996307 -121.8057245 46.85 48.76 -------- Geotracker Monitoring Unknown T0601300782-MW-10 37.9996463 -121.8058044 47.54 48.76 -------- Geotracker Monitoring Unknown T0601300782-MW-11 37.9999907 -121.8050581 48.80 46.67 -------- Geotracker Monitoring Unknown T0601300782-MW-12 37.9994011 -121.8057835 45.11 48.53 -------- Geotracker Monitoring Unknown T0601300782-MW-13 38.000166 -121.8054461 51.26 49.84 -------- Geotracker Monitoring Unknown T0601300782-MW-14 38.0002065 -121.8050629 51.23 48.04 -------- Geotracker Monitoring Unknown T0601300782-MW-15 38.0002315 -121.8046597 45.57 47.86 -------- Geotracker Monitoring Unknown T0601300782-MW-2 37.9995903 -121.8054568 46.87 46.35 -------- Geotracker Monitoring Unknown T0601300782-MW-3 37.999989 -121.8056984 49.20 49.53 -------- Geotracker Monitoring Unknown T0601300782-MW-4 37.9997408 -121.80519 45.74 46.04 -------- Geotracker Monitoring Unknown T0601300782-MW-5 37.9995248 -121.8050439 40.91 45.10 -------- Geotracker Monitoring Unknown T0601300782-MW-6 37.9993948 -121.8053151 43.01 45.89 -------- Geotracker Monitoring Unknown T0601300782-MW-7 37.9996347 -121.8055954 46.58 48.16 -------- Geotracker Monitoring Unknown T0601300782-MW-8 37.9999792 -121.8050587 48.75 46.67 -------- Geotracker Monitoring Unknown T0601300782-MW-9 37.9997318 -121.8051919 45.54 46.04 -------- Geotracker Monitoring Unknown T0601300783-DW-1 37.9338985 -121.6947746 74.84 -115.71 -------- Geotracker Monitoring Unknown T0601300783-DW-2 37.9338623 -121.6946215 75.24 -104.59 -------- Geotracker Monitoring Unknown T0601300783-DW-3 37.9337577 -121.6947067 75.87 -115.71 -------- Geotracker Monitoring Unknown T0601300783-MW-1 37.9339431 -121.6945458 73.19 76.35 -------- Geotracker Monitoring Unknown T0601300783-MW-10 37.933722 -121.6948574 75.58 -115.71 -------- Page 7 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown T0601300783-MW-11 37.9338062 -121.6950794 74.22 -115.71 -------- Geotracker Monitoring Unknown T0601300783-MW-12 37.9339449 -121.6952019 73.83 -115.71 -------- Geotracker Monitoring Unknown T0601300783-MW-13 37.9341922 -121.694762 73.44 -115.71 -------- Geotracker Monitoring Unknown T0601300783-MW-2 37.9339136 -121.6947852 73.57 76.37 -------- Geotracker Monitoring Unknown T0601300783-MW-3 37.9337748 -121.6947274 73.85 76.69 -------- Geotracker Monitoring Unknown T0601300783-MW-4 37.9338912 -121.6946925 73.44 76.38 -------- Geotracker Monitoring Unknown T0601300783-MW-5 37.9338637 -121.6943877 73.11 76.52 -------- Geotracker Monitoring Unknown T0601300783-MW-6 37.933667 -121.694518 74.91 77.00 -------- Geotracker Monitoring Unknown T0601300783-MW-7 37.9340007 -121.6946443 72.92 76.35 -------- Geotracker Monitoring Unknown T0601300783-MW-9 37.9336898 -121.6946859 76.32 -104.59 -------- Geotracker Monitoring Unknown T0601300783-SVE-1 37.9338808 -121.6946499 73.26 76.52 -------- Geotracker Monitoring Unknown T0601300783-SVE-2 37.9338698 -121.6946129 73.66 76.52 -------- Geotracker Monitoring Unknown T0601300784-MW-1 38.00462582 -121.7968979 17.20 -90.41 -------- Geotracker Monitoring Unknown T0601300784-MW-2 38.00462382 -121.7970015 18.36 -90.41 -------- Geotracker Monitoring Unknown T0601300784-MW-3 38.00462582 -121.7968979 18.05 -90.41 -------- Geotracker Monitoring Unknown T0601300788-MW-1 38.017041 -121.8176197 7.60 -76.63 -------- Geotracker Monitoring Unknown T0601300788-MW-2 38.0175466 -121.8177886 8.10 -76.63 -------- Geotracker Monitoring Unknown T0601300788-MW-3 38.0175677 -121.8174347 7.94 -76.63 -------- Geotracker Monitoring Unknown T0601300788-MW-4 38.0168336 -121.8177861 8.59 -76.63 -------- Geotracker Monitoring Unknown T0601300788-MW-5 38.0172165 -121.8179011 6.66 -76.63 -------- Geotracker Monitoring Unknown T0601300788-MW-6 38.016827 -121.8174841 8.50 -76.63 -------- Geotracker Monitoring Unknown T0601300788-TW-1 38.0168371 -121.8174983 8.67 -76.63 -------- Geotracker Monitoring Unknown T0601300788-TW-2 38.0169581 -121.817657 8.21 -76.63 -------- Geotracker Monitoring Unknown T0601300788-TW-3 38.0169435 -121.8174682 8.81 -76.63 -------- Geotracker Monitoring Unknown T0601300788-TW-4 38.0169572 -121.8180571 9.00 -76.63 -------- Geotracker Monitoring Unknown T0601300790-MW-1 38.01081896 -121.8193194 18.67 21.47 -------- Geotracker Monitoring Unknown T0601300790-MW-2 38.01108911 -121.8193669 17.03 20.93 -------- Geotracker Monitoring Unknown T0601300790-MW-3 38.01104125 -121.81954 17.70 21.37 -------- Geotracker Monitoring Unknown T0601300790-MW-4 38.01124995 -121.8194669 16.79 20.51 -------- Geotracker Monitoring Unknown T0601300790-MW-5 38.01126429 -121.8192493 16.35 20.18 -------- Geotracker Monitoring Unknown T0601300790-MW-6 38.01109116 -121.8189549 16.02 20.48 -------- Geotracker Monitoring Unknown T0601300800-BW-1 38.0046866 -121.8057268 42.82 -85.29 -------- Geotracker Monitoring Unknown T0601300800-MW-2 38.0046401 -121.8054315 41.73 -85.29 -------- Geotracker Monitoring Unknown T0601300800-MW-3 38.0043868 -121.8055792 42.44 -85.29 -------- Geotracker Monitoring Unknown T0601300800-MW-4A 38.003852 -121.8054135 41.41 -81.54 -------- Geotracker Monitoring Unknown T0601300800-MW-4B 38.0038556 -121.8053971 41.36 -81.54 -------- Geotracker Monitoring Unknown T0601300800-MW-5B 38.004459 -121.8052784 42.48 -85.29 -------- Geotracker Monitoring Unknown T0601300800-MW-6A 38.0047369 -121.8048701 39.05 -85.29 -------- Geotracker Monitoring Unknown T0601300800-MW-6B 38.0047369 -121.8048853 39.07 -85.29 -------- Geotracker Monitoring Unknown T0601300800-MW-7B 38.0046698 -121.8057534 41.82 -85.29 -------- Geotracker Monitoring Unknown T0601300800-MW-7BL 38.0046456 -121.8057491 41.51 -85.29 -------- Geotracker Monitoring Unknown T0601300800-MW-8A 38.0041158 -121.8051278 40.99 -85.29 -------- Geotracker Monitoring Unknown T0601300800-MW-8BL 38.0041314 -121.8051336 41.08 -85.29 -------- Geotracker Monitoring Unknown T0601300802-MW-1 37.941038 -121.6959902 67.30 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-10 37.9411273 -121.6964507 67.59 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-11 37.9414786 -121.6963074 66.51 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-12 37.9414863 -121.6951664 63.75 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-13 37.9412149 -121.6953829 64.73 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-14 37.9408431 -121.6960057 65.83 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-15D 37.9412418 -121.695776 67.45 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-16D 37.9415004 -121.695639 64.97 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-17D 37.9408886 -121.6960089 65.49 -81.20 -------- Page 8 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown T0601300802-MW-2 37.9411159 -121.6958018 68.28 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-3 37.9413126 -121.6959225 66.48 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-4 37.9415101 -121.6958174 65.60 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-5 37.9415103 -121.695651 65.13 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-6 37.9414869 -121.6954125 64.16 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-7 37.9418024 -121.6955387 65.08 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-8 37.9410984 -121.6963133 66.86 -81.20 -------- Geotracker Monitoring Unknown T0601300802-MW-9D 37.9410475 -121.6957993 68.30 -81.20 -------- Geotracker Monitoring Unknown T0601300802-OS-1 37.9410457 -121.6960267 67.24 -81.20 -------- Geotracker Monitoring Unknown T0601300802-OS-2 37.9410882 -121.6958212 68.30 -81.20 -------- Geotracker Monitoring Unknown T0601300802-OS-3 37.941276 -121.6958569 67.04 -81.20 -------- Geotracker Monitoring Unknown T0601300803-STAS-1 38.011774 -121.8058837 17.98 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STEVE-13 38.0118588 -121.8058973 17.25 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STEW-23 38.0116088 -121.8061896 18.49 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STEW-24 38.0114365 -121.8061786 18.68 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STEW-25 38.0112772 -121.806245 17.86 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STEW-26 38.0113862 -121.8064065 17.91 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-1 38.0115736 -121.8061876 18.59 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-17 38.0110702 -121.8059374 20.92 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-18 38.0118899 -121.8059672 17.48 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-19 38.011466 -121.8059537 19.05 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-2 38.0113018 -121.8061832 18.66 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-20 38.0110872 -121.806167 18.79 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-21 38.0117921 -121.8063265 17.64 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-22 38.0115068 -121.806571 17.99 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-27 38.0110924 -121.8058268 23.13 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-28 38.0110321 -121.8056538 24.83 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-29 38.0120502 -121.806349 17.07 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-30 38.0123365 -121.8060766 17.83 -91.08 -------- Geotracker Monitoring Unknown T0601300803-STMW-31 38.0111335 -121.8065357 16.61 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-32 38.0112789 -121.8066071 17.03 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-33 38.0108919 -121.8057424 22.79 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-34 38.0112001 -121.8050437 35.00 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-35 38.0116127 -121.8050609 30.25 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-36 38.011544 -121.8053608 37.73 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-4 38.0115614 -121.8064594 18.35 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-5 38.011647 -121.8062696 18.87 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-6 38.0114208 -121.8064288 18.14 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-7 38.0115972 -121.8063492 18.83 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMW-8 38.0117668 -121.806259 17.61 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMWD-10 38.0112875 -121.8064219 17.22 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMWD-11 38.0110778 -121.8059378 20.82 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMWD-12 38.011473 -121.8059533 19.21 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMWD-14 38.0117338 -121.8061973 18.37 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMWD-15 38.0113013 -121.8062104 18.44 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMWD-16 38.0110793 -121.8061552 18.99 -88.75 -------- Geotracker Monitoring Unknown T0601300803-STMWD-9 38.0115802 -121.8064446 18.62 -88.75 -------- Geotracker Monitoring Unknown T0601300804-EW-1 37.933947 -121.6983042 78.06 -115.71 -------- Geotracker Monitoring Unknown T0601300804-EW-2 37.9340563 -121.6980679 77.09 -115.71 -------- Geotracker Monitoring Unknown T0601300804-EW-3 37.9342196 -121.698215 75.88 -115.71 -------- Geotracker Monitoring Unknown T0601300804-EW-4 37.9341331 -121.6983485 77.15 -115.71 -------- Geotracker Monitoring Unknown T0601300804-EW-5 37.9343278 -121.6983093 75.97 -115.71 -------- Page 9 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown T0601300804-EW-6 37.934265 -121.6984956 77.13 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-1 37.9339856 -121.6983873 78.55 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-10 37.9334922 -121.6986553 76.39 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-11 37.9344076 -121.6987493 77.64 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-12 37.9332716 -121.6985076 76.61 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-12A 37.9332601 -121.6984381 76.85 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-13 37.9334587 -121.6975276 77.36 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-14 37.933498 -121.6964006 75.37 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-15B 37.9340422 -121.6991599 75.91 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-16B 37.9343563 -121.698675 77.21 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-17B 37.9340314 -121.6984518 78.07 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-2A 37.9337241 -121.698056 78.11 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-3 37.9341415 -121.6981199 76.90 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-4 37.9344467 -121.6984594 76.44 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-5 37.9342927 -121.6986578 77.71 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-6 37.9339419 -121.6990277 76.80 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-6D 37.933941 -121.6990473 76.16 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-7 37.9344388 -121.6974999 76.07 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-7D 37.9344507 -121.6974775 76.00 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-8 37.9345152 -121.6966418 74.10 -115.71 -------- Geotracker Monitoring Unknown T0601300804-MW-9 37.9346687 -121.6975854 76.47 -115.71 -------- Geotracker Monitoring Unknown T0601300807-IP-1 38.0048006 -121.806461 40.81 -85.29 -------- Geotracker Monitoring Unknown T0601300807-IP-2 38.0047763 -121.8064748 41.25 -85.29 -------- Geotracker Monitoring Unknown T0601300807-MW-1 38.0047156 -121.806184 41.33 -85.29 -------- Geotracker Monitoring Unknown T0601300807-MW-2 38.0047769 -121.806228 41.18 -85.29 -------- Geotracker Monitoring Unknown T0601300807-MW-3 38.0046278 -121.8063643 42.35 -85.29 -------- Geotracker Monitoring Unknown T0601300807-MW-4 38.0050061 -121.8061174 40.18 -85.29 -------- Geotracker Monitoring Unknown T0601300807-MW-5 38.004464 -121.8063128 42.36 -85.29 -------- Geotracker Monitoring Unknown T0601300807-MW-5B 38.0044643 -121.8063393 41.86 -85.29 -------- Geotracker Monitoring Unknown T0601300807-MW-5C 38.0044652 -121.8063584 41.93 -85.29 -------- Geotracker Monitoring Unknown T0601300807-MW-6 38.004798 -121.8064968 41.16 -85.29 -------- Geotracker Monitoring Unknown T0601300807-OW-1 38.0047842 -121.8064498 41.14 -85.29 -------- Geotracker Monitoring Unknown T0601300807-OW-2 38.0047805 -121.8064347 41.28 -85.29 -------- Geotracker Monitoring Unknown T0601300807-S-11 38.0047895 -121.8063677 41.05 -85.29 -------- Geotracker Monitoring Unknown T0601300807-S-12 38.0049592 -121.8057025 39.23 -85.29 -------- Geotracker Monitoring Unknown T0601300807-S-13 38.004603 -121.8060185 41.46 -85.29 -------- Geotracker Monitoring Unknown T0601300807-S-14 38.0047989 -121.8069236 40.38 -79.68 -------- Geotracker Monitoring Unknown T0601300807-S-15 38.0050037 -121.8067263 39.72 -79.68 -------- Geotracker Monitoring Unknown T0601300807-S-17 38.0052567 -121.8059382 39.66 -85.29 -------- Geotracker Monitoring Unknown T0601300807-S-7 38.0045469 -121.8067045 41.73 -79.68 -------- Geotracker Monitoring Unknown T0601300807-S-8 38.0047989 -121.8066962 40.40 -79.68 -------- Geotracker Monitoring Unknown T0601300809-MW-1 38.0112956 -121.8184385 13.27 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-10 38.0116934 -121.8183619 13.71 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-102 38.0115302 -121.8181231 14.30 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-103 38.0115097 -121.8180083 14.28 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-104 38.0118684 -121.8180428 13.24 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-11 38.0110934 -121.8184786 13.93 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-12 38.0118666 -121.8182772 13.86 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-13 38.011868 -121.8181249 13.64 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-14 38.0118708 -121.817868 12.78 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-2 38.0111612 -121.8181371 12.58 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-3 38.0113382 -121.8180056 13.33 -70.53 -------- Page 10 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown T0601300809-MW-4 38.0113958 -121.8183385 13.77 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-5 38.0114142 -121.8181693 14.36 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-6 38.0114107 -121.818011 14.00 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-7 38.0115183 -121.8183359 14.00 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-8 38.0115242 -121.8181439 14.53 -70.53 -------- Geotracker Monitoring Unknown T0601300809-MW-9 38.0114921 -121.8180102 14.42 -70.53 -------- Geotracker Monitoring Unknown T0601300810-MW-1 38.017207 -121.752913 9.47 -104.84 -------- Geotracker Monitoring Unknown T0601300810-MW-2 38.0171331 -121.7529023 8.54 -104.84 -------- Geotracker Monitoring Unknown T0601300810-MW-3 38.017163 -121.7530978 8.72 -104.84 -------- Geotracker Monitoring Unknown T0601300810-MW-4 38.0174218 -121.7529407 9.59 -104.84 -------- Geotracker Monitoring Unknown T0601300810-MW-5 38.0174601 -121.7532544 8.74 -104.84 -------- Geotracker Monitoring Unknown T0601300810-MW-6 38.0172799 -121.7529025 9.65 -104.84 -------- Geotracker Monitoring Unknown T0601300810-MW-7 38.0172388 -121.7532734 9.18 -104.84 -------- Geotracker Monitoring Unknown T0601306725-MW-1 37.9941196 -121.8082977 86.87 -70.22 -------- Geotracker Monitoring Unknown T0601306725-MW-2 37.9939988 -121.8082726 87.00 -70.22 -------- Geotracker Monitoring Unknown T0601306725-MW-3 37.9941265 -121.8081169 85.45 -70.22 -------- Geotracker Monitoring Unknown T0601306725-MW-4 37.9938456 -121.8080293 86.58 -70.22 -------- Geotracker Monitoring Unknown T0601306725-MW-5 37.993993 -121.8081341 86.29 -70.22 -------- Geotracker Monitoring Unknown T0601306725-MW-6 37.994052 -121.8080616 85.36 -70.22 -------- Geotracker Monitoring Unknown T0601306725-MW-8 37.9944661 -121.8088979 90.60 -70.22 -------- Geotracker Monitoring Unknown T0601325015-MPE-1 38.00379078 -121.787085 37.99 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MPE-2 38.0037754 -121.787005 37.92 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MPE-3 38.00378277 -121.7869815 37.79 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-1 38.0037825 -121.7872783 38.24 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-1D 38.00376017 -121.7869873 37.89 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-2 38.003891 -121.7870598 37.19 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-2D 38.00391916 -121.7870492 36.75 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-3 38.0037733 -121.7870175 37.98 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-3D 38.00417987 -121.7867559 31.20 -99.23 -------- Geotracker Monitoring Unknown T0601325015-MW-4 38.0037847 -121.7870444 37.84 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-4R 38.00375461 -121.7870441 37.76 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-5 38.00376206 -121.7869392 37.83 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-6 38.00364211 -121.7869787 38.55 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-7 38.00510029 -121.7870266 38.20 -99.23 -------- Geotracker Monitoring Unknown T0601325015-MW-8 38.00390386 -121.7869723 37.11 -96.14 -------- Geotracker Monitoring Unknown T0601325015-MW-9 38.00418017 -121.7868248 31.71 -99.23 -------- Geotracker Monitoring Unknown T0601330032-MW1 37.8672165 -121.637895 27.35 -132.11 -------- Geotracker Monitoring Unknown T0601330032-MW2 37.8673126 -121.6380089 28.14 -132.11 -------- Geotracker Monitoring Unknown T0601330032-MW3 37.867352 -121.6378623 26.48 -132.11 -------- Geotracker Monitoring Unknown T0601330032-MW4 37.8672745 -121.6377914 26.34 -132.11 -------- Geotracker Monitoring Unknown T0601341681-MW-1 38.0155474 -121.8077961 16.40 -85.68 -------- Geotracker Monitoring Unknown T0601341681-MW-2 38.0157695 -121.8078475 12.24 -85.68 -------- Geotracker Monitoring Unknown T0601341681-MW-3 38.0157133 -121.8076686 12.85 -85.68 -------- Geotracker Monitoring Unknown T0601343310-EW1 37.9406647 -121.6966186 66.67 -81.20 -------- Geotracker Monitoring Unknown T0601343310-EW2 37.9408713 -121.6964843 68.96 -81.20 -------- Geotracker Monitoring Unknown T0601343310-EW3 37.9408789 -121.6963383 68.04 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW1 37.9409865 -121.6963442 67.73 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW-10 37.9413084 -121.6965237 67.93 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW-11 37.9408574 -121.6954799 66.75 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW-12 37.940741 -121.6960109 66.80 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW-13 37.9415908 -121.6946485 64.64 -73.34 -------- Geotracker Monitoring Unknown T0601343310-MW-14 37.9399551 -121.694452 65.46 -73.34 -------- Page 11 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown T0601343310-MW-15 37.940808 -121.693002 63.13 -73.34 -------- Geotracker Monitoring Unknown T0601343310-MW-16 37.9426677 -121.6946332 64.38 -73.34 -------- Geotracker Monitoring Unknown T0601343310-MW-17 37.9426195 -121.6936784 62.45 -73.34 -------- Geotracker Monitoring Unknown T0601343310-MW-18 37.9418714 -121.6932068 61.90 -73.34 -------- Geotracker Monitoring Unknown T0601343310-MW2 37.9408115 -121.6965066 69.34 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW3 37.9408318 -121.696335 67.90 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW4 37.9409874 -121.6963695 66.94 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW-5 37.9407746 -121.6965089 68.89 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW-6 37.9407223 -121.6965102 68.02 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW-7 37.9409531 -121.6963744 68.02 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW-8 37.940761 -121.6963398 67.30 -81.20 -------- Geotracker Monitoring Unknown T0601343310-MW-9 37.9411349 -121.6965732 68.58 -81.20 -------- Geotracker Monitoring Unknown T0601358660-MW1 38.00225 -121.74275 38.15 -94.65 -------- Geotracker Monitoring Unknown T0601358660-MW2 38.00162918 -121.7418966 37.28 -94.65 -------- Geotracker Monitoring Unknown T0601358660-MW3 38.00141 -121.74316 35.85 -94.65 -------- Geotracker Monitoring Unknown T0601358660-MW4 38.00136 -121.74373 35.99 -96.28 -------- Geotracker Monitoring Unknown T0601359254-MW-1 37.9345134 -121.6920427 70.06 -104.59 -------- Geotracker Monitoring Unknown T0601359254-MW-2 37.934424 -121.6920187 70.67 -104.59 -------- Geotracker Monitoring Unknown T0601359254-MW-3 37.9343979 -121.6920626 70.89 -104.59 -------- Geotracker Monitoring Unknown T0601359797-AS-1 38.0004624 -121.8063424 53.28 -81.54 -------- Geotracker Monitoring Unknown T0601359797-AS-2 38.0003826 -121.8063497 52.74 -81.54 -------- Geotracker Monitoring Unknown T0601359797-AS-3 38.0004393 -121.8062461 52.86 -81.54 -------- Geotracker Monitoring Unknown T0601359797-AS-4 38.00051 -121.8062117 52.95 -81.54 -------- Geotracker Monitoring Unknown T0601359797-AS-5 38.0004667 -121.8061782 52.33 -81.54 -------- Geotracker Monitoring Unknown T0601359797-AS-6 38.0005619 -121.8061785 52.51 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW-10 38.00034 -121.8061452 52.47 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW11 38.0002488 -121.8066484 53.42 -76.07 -------- Geotracker Monitoring Unknown T0601359797-MW12 37.9999553 -121.806154 52.28 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW-13 38.0006519 -121.8039583 44.81 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW14 38.0006719 -121.8049529 47.89 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW-15 38.0011521 -121.8049933 48.98 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW-16 38.001097 -121.8042347 46.91 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW-4 38.0004963 -121.8064013 53.69 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW-5 38.0008867 -121.8063317 51.12 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW-6 38.0006217 -121.8055473 50.11 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW-7 38.0004348 -121.8058214 52.47 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW-8 38.0002484 -121.805824 52.79 -81.54 -------- Geotracker Monitoring Unknown T0601359797-MW-9 38.0002058 -121.8063305 52.47 -81.54 -------- Geotracker Monitoring Unknown T0601359797-RW-1 38.0005311 -121.8063645 53.27 -81.54 -------- Geotracker Monitoring Unknown T0601359797-RW-2 38.0004512 -121.8063673 53.44 -81.54 -------- Geotracker Monitoring Unknown T0601359797-RW-3 38.0003611 -121.8063564 53.03 -81.54 -------- Geotracker Monitoring Unknown T0601359797-RW-4 38.0004463 -121.8062016 52.49 -81.54 -------- Geotracker Monitoring Unknown T0601359797-RW-5 38.0005447 -121.8062075 52.73 -81.54 -------- Geotracker Monitoring Unknown T0601376629-MW1 37.9015462 -121.6027962 5.67 -188.27 -------- Geotracker Monitoring Unknown T0601376629-MW2 37.9013569 -121.6026365 5.02 -188.27 -------- Geotracker Monitoring Unknown T0601376629-MW3 37.9017111 -121.6025489 4.87 -188.27 -------- Geotracker Monitoring Unknown T0601376629-MW4 37.9016078 -121.6023867 4.12 -188.27 -------- Geotracker Monitoring Unknown T0601378938-MW-1 38.022473 -121.6351696 -4.91 -157.83 -------- Geotracker Monitoring Unknown T0601378938-MW-10 38.0225654 -121.6354574 -5.78 -157.83 -------- Geotracker Monitoring Unknown T0601378938-MW-2 38.0225757 -121.6352857 -5.48 -157.83 -------- Geotracker Monitoring Unknown T0601378938-MW-3 38.0225125 -121.6354305 -5.70 -157.83 -------- Geotracker Monitoring Unknown T0601378938-MW-4 38.0224013 -121.6354456 -5.23 -157.83 -------- Page 12 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown T0601378938-MW-5 38.0223448 -121.6355005 -5.41 -157.83 -------- Geotracker Monitoring Unknown T0601378938-MW-6 38.0224618 -121.6355097 -5.57 -157.83 -------- Geotracker Monitoring Unknown T0601378938-MW-7 38.0224048 -121.6355837 -5.42 -157.83 -------- Geotracker Monitoring Unknown T0601378938-MW-8 38.0224904 -121.6355946 -5.11 -157.83 -------- Geotracker Monitoring Unknown T0601378938-MW-9 38.0225315 -121.6355573 -5.61 -157.83 -------- Geotracker Monitoring Unknown T0601389036-B-1 38.0143284 -121.8223385 14.81 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-10 38.0144288 -121.8229225 14.20 -67.49 -------- Geotracker Monitoring Unknown T0601389036-B-11 38.0146595 -121.8227285 14.10 -67.49 -------- Geotracker Monitoring Unknown T0601389036-B-12 38.0148006 -121.8232961 14.15 -67.49 -------- Geotracker Monitoring Unknown T0601389036-B-13 38.0148774 -121.822838 15.63 -67.49 -------- Geotracker Monitoring Unknown T0601389036-B-14 38.0149575 -121.8222889 16.38 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-15 38.0147289 -121.8217368 15.57 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-16 38.0143977 -121.8221377 14.60 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-17 38.0144926 -121.8223497 15.25 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-18 38.0144113 -121.8223691 14.95 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-19 38.0143675 -121.8223227 15.47 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-2 38.0144601 -121.8223304 15.06 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-20 38.0144731 -121.8222703 15.63 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-21 38.0144038 -121.8222156 15.54 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-3 38.0144906 -121.8222021 14.93 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-4 38.0143271 -121.8222114 14.66 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-5 38.0140936 -121.8223943 13.34 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-6 38.0145447 -121.8224989 14.99 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-7 38.0147467 -121.8221309 15.28 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-8 38.0142517 -121.8219895 14.20 -73.77 -------- Geotracker Monitoring Unknown T0601389036-B-9 38.0140827 -121.8228979 14.27 -67.49 -------- Geotracker Monitoring Unknown T0601389036-BC-1-10 38.0144622 -121.8223235 15.28 -73.77 -------- Geotracker Monitoring Unknown T0601389036-BC-1-15 38.0144622 -121.8223235 15.28 -73.77 -------- Geotracker Monitoring Unknown T0601389036-BC-1-20 38.0144622 -121.8223235 15.28 -73.77 -------- Geotracker Monitoring Unknown T0601389036-BC-1-25 38.0144622 -121.8223235 15.28 -73.77 -------- Geotracker Monitoring Unknown T0601389036-BC-1-30 38.0144622 -121.8223235 15.28 -73.77 -------- Geotracker Monitoring Unknown T0601389036-BC-1-35 38.0144622 -121.8223235 15.28 -73.77 -------- Geotracker Monitoring Unknown T0601389036-BC-1-40 38.0144622 -121.8223235 15.28 -73.77 -------- Geotracker Monitoring Unknown T0601389036-BC-1-5 38.0144622 -121.8223235 15.28 -73.77 -------- Geotracker Monitoring Unknown T0601389036-MW-1 38.0143185 -121.8222422 14.91 -73.77 -------- Geotracker Monitoring Unknown T0601389036-MW-2 38.0145542 -121.8221808 14.95 -73.77 -------- Geotracker Monitoring Unknown T0601389036-MW-3 38.0144717 -121.8223222 15.32 -73.77 -------- Geotracker Monitoring Unknown T0601389417-MW-1 37.9901263 -121.6677145 9.00 -182.30 -------- Geotracker Monitoring Unknown T0601391419-MW-1 38.016101 -121.7494516 9.31 -104.41 -------- Geotracker Monitoring Unknown T0601391419-MW-2 38.0160282 -121.749727 8.90 -104.41 -------- Geotracker Monitoring Unknown T0601391419-MW-3 38.016271 -121.7497524 9.65 -104.41 -------- Geotracker Monitoring Unknown T0601391420-EX-1 38.01268769 -121.8292119 29.52 -61.35 -------- Geotracker Monitoring Unknown T0601391420-EX-2 38.01269103 -121.8292322 29.31 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-1 38.01280491 -121.8291715 29.08 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-1-I 38.01267281 -121.8292351 29.38 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-2 38.01265159 -121.8294185 29.06 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-2-I 38.01236483 -121.8295102 29.93 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-3 38.01279778 -121.8293977 29.14 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-3-I 38.01278438 -121.829472 29.43 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-4 38.01273845 -121.8295932 29.22 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-4-I 38.01274235 -121.8292256 29.56 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-5 38.01310269 -121.8296761 28.52 -61.35 -------- Page 13 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) Geotracker Monitoring Unknown T0601391420-MW-5-I 38.01249205 -121.8293584 30.07 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-6 38.01267481 -121.8292231 29.32 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-7 38.01260006 -121.828653 29.01 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-8 38.01236228 -121.8287389 29.33 -61.35 -------- Geotracker Monitoring Unknown T0601391420-MW-9 38.01266 -121.82954 29.55 -61.35 -------- Geotracker Monitoring Unknown T10000000655-MW.01 38.0153839 -121.8248692 15.32 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.02 38.0153843 -121.8247034 15.60 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.03 38.0153848 -121.824538 15.64 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.04 38.0153139 -121.8248692 14.76 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.05 38.0152891 -121.8247623 14.97 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.06 38.0152439 -121.8248197 14.90 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.07 38.0152455 -121.8247024 14.86 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.08 38.0151986 -121.824761 14.89 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.09 38.0152438 -121.824763 14.91 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.10 38.0151097 -121.8249689 14.86 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.11 38.0153347 -121.8249879 14.87 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.12 38.0152557 -121.8249579 15.05 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.13 38.0151759 -121.8248509 14.98 -67.49 -------- Geotracker Monitoring Unknown T10000000655-MW.14 38.0151362 -121.8246593 15.04 -67.49 -------- Geotracker Monitoring Unknown T10000002015-B-1 37.925711 -121.733845 123.81 -121.19 -------- Geotracker Monitoring Unknown T10000002015-B-2 37.925701 -121.733699 123.24 -121.19 -------- Geotracker Monitoring Unknown T10000002015-B-3 37.925658 -121.733912 123.88 -121.19 -------- Geotracker Monitoring Unknown T10000002015-B-4 37.925591 -121.733775 123.89 -121.19 -------- Geotracker Monitoring Unknown T10000002015-MW-1 37.925573 -121.733774 123.61 -121.19 -------- Geotracker Monitoring Unknown T10000002015-MW-2 37.92568 -121.733619 126.41 -121.19 -------- Geotracker Monitoring Unknown T10000002015-MW-3 37.925613 -121.733985 124.29 -121.19 -------- Geotracker Monitoring Unknown T10000002015-MW-4 37.925805 -121.733792 125.46 -121.19 -------- Geotracker Monitoring Unknown T10000002015-MW-5 37.925501 -121.733773 124.55 -121.19 -------- Geotracker Monitoring Unknown T10000003258-MW-1 37.939064 -121.5784564 -7.20 -183.53 -------- Geotracker Monitoring Unknown T10000003258-MW-2 37.9390629 -121.5778783 -7.30 -183.53 -------- Geotracker Monitoring Unknown T10000003258-MW-3 37.9391663 -121.5781884 -11.94 -183.53 -------- Geotracker Monitoring Unknown T10000003258-MW-4 37.9391678 -121.5779586 -11.68 -183.53 -------- Geotracker Monitoring Unknown T10000003258-MW-5 37.9394031 -121.5782836 -8.66 -183.53 -------- Geotracker Monitoring Unknown T10000003258-MW-6 37.939404 -121.5778654 -9.82 -183.53 -------- Geotracker Monitoring Unknown T10000003258-MW-7 37.9390637 -121.5781095 -7.33 -183.53 -------- USGS --Shallow USGS-375106121372201 37.8515927 -121.6238399 --25.20 ------45 USGS --Shallow USGS-375202121383101 37.8671477 -121.643007 34.00 34.48 ------135 USGS --Shallow USGS-375347121372201 37.8963137 -121.6238404 8.00 5.25 ------110 USGS --Shallow USGS-375410121412401 37.9027022 -121.6910637 89.00 92.56 ------85 USGS --Shallow USGS-375427121422601 37.9074242 -121.7082863 107.00 109.99 ------98 USGS --Shallow USGS-375449121435301 37.9135351 -121.7324534 --136.44 ------60 USGS --Shallow USGS-375600121402601 37.933257 -121.6749527 55.00 55.34 ------123 USGS --Shallow USGS-375601121415201 37.9335347 -121.6988419 75.00 78.06 ------145 USGS --Shallow USGS-375701121392901 37.9502011 -121.6591193 --36.17 ------60 USGS --Shallow USGS-375738121441501 37.9604783 -121.7385648 124.00 114.99 ------80 USGS --Shallow USGS-375753121422801 37.9646449 -121.7088422 70.00 72.39 ------133 USGS --Shallow USGS-375831121424001 37.9752002 -121.7121757 75.00 77.41 ------130 USGS --Shallow USGS-375916121403401 37.9877 -121.6771754 6.00 15.45 ------88 USGS --Shallow USGS-380012121461101 38.0032549 -121.770788 44.00 51.43 ------95 USGS --Shallow USGS-380016121454501 38.004366 -121.7635656 60.00 53.51 ------140 USGS --Shallow USGS-380017121443201 38.0047222 -121.7416667 29.00 29.68 ------82 USGS --Shallow USGS-380017121455901 38.0046437 -121.7674546 51.00 47.33 ------120 Page 14 of 15 Well Construction Table-East Contra Costa Subbasin, Geotracker and USGS Wells Owner/GSA/ Monitoring Agency Well Type Zone Desgination Well Name Latitude Longitude TOC Elev. (ft msl) Ground Surface Elevation Screen Interval (ft bgs) Top of Screen Interval (ft msl) Bottom of Screen Interval (ft msl) Well Depth (ft bgs) USGS --Shallow USGS-380019121464601 38.0051992 -121.7805105 --49.28 ------93 USGS --Shallow USGS-380020121443901 38.0054771 -121.7452318 26.00 25.82 ------66 USGS --Shallow USGS-380025121471101 38.0118657 -121.7710659 --32.36 ------78 USGS --Shallow USGS-380043121461201 38.0132546 -121.7702326 28.00 27.96 ------67 USGS --Shallow USGS-380048121470701 38.0151994 -121.6288418 5.00 8.03 ------165 USGS --Deep USGS-375437121355601 37.9102023 -121.5999513 --3.00 ------355 USGS --Deep USGS-375600121410901 37.933257 -121.6868973 --66.06 ------230 USGS --Deep USGS-380019121473401 38.0051992 -121.7938443 --18.95 ------190 USGS --Deep USGS-380024121490801 38.006588 -121.8199562 27.00 24.59 ------124 USGS --Deep USGS-380024121490803 38.0068659 -121.7874552 17.00 15.95 ------140 USGS --Deep USGS-380048121460901 38.0132545 -121.7863441 --31.63 ------500 USGS --Deep USGS-380055121374001 38.0171433 -121.8032891 --5.14 ------176 USGS --Deep USGS-380102121480801 38.0382542 -121.6368976 --2.59 ------258 USGS --Deep USGS-380218121380901 38.006588 -121.8199562 26.00 24.59 ------130 USGS --Composite USGS-375228121382001 37.8743698 -121.6399515 --32.22 ------185 USGS --Composite USGS-375619121353001 37.9385349 -121.5927293 -13.00 3.71 ------176 USGS --Unknown USGS-380024121471501 38.0065881 -121.7885663 --8.96 -------- Abbreviations: ft- feet bgs- below ground surface TOC- Top of Casing GSA- Groundwater Sustainability Agency msl- mean sea level USGS-United States Geological Survey Page 15 of 15 Groundwater Level Hydrographs APPENDIX 3d 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)11 16 21 26 31 36 41 46 51 56 61 GW Elevation(ft,NAVD88) WellID: Blossom Well Owner:Antioch Zone: Shallow Well Depth (ft): 8860-88Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -23 -18 -13 -8 -3 2 7 12 17 22 27 GW Elevation(ft,NAVD88) WellID: 1 JNJ Owner:BBID Zone: Shallow Well Depth (ft): 120105-120Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-18 -13 -8 -3 2 7 12 17 22 27 32 GWElevation(ft,NAVD88)WellID:3 Byron Owner:BBID Zone:Shallow Well Depth (ft):7050-70Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -14 -9 -4 1 6 11 16 21 26 31 36 GWElevation(ft,NAVD88)WellID:4 Bruns Owner:BBID Zone:Shallow Well Depth (ft):6545-65Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-26 -21 -16 -11 -6 -1 4 9 14 19 24 GW Elevation(ft,NAVD88) WellID: 5 Binn Owner:BBID Zone: Shallow Well Depth (ft): 45N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) 21 26 31 36 41 46 51 56 61 66 71 GW Elevation(ft,NAVD88) WellID: BG-1 Owner:CofB Zone: Shallow Well Depth (ft): 5540-55Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)12 17 22 27 32 37 42 47 52 57 62 GWElevation(ft,NAVD88)WellID:BG-2 Owner:CofB Zone:Shallow Well Depth (ft):37.522.5-37.5Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) 6 11 16 21 26 31 36 41 46 51 56 GWElevation(ft,NAVD88)WellID:BG-3 Owner:CofB Zone:Shallow Well Depth (ft):3520-35Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) 23 28 33 38 43 48 53 58 63 68 73 GWElevation(ft,NAVD88)WellID: 5-2 Owner:ECCID Zone: Shallow Well Depth (ft): <20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID: 5-33 Owner:ECCID Zone: Shallow Well Depth (ft): 11N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:5-34 Owner:ECCID Zone:Shallow Well Depth (ft):11N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -26 -21 -16 -11 -6 -1 4 9 14 19 24 GWElevation(ft,NAVD88)WellID:5-35 Owner:ECCID Zone:Shallow Well Depth (ft):11N/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -23 -18 -13 -8 -3 2 7 12 17 22 27 GWElevation(ft,NAVD88)WellID: 5-36 Owner:ECCID Zone: Shallow Well Depth (ft): 11N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID: 5-37 Owner:ECCID Zone: Shallow Well Depth (ft): >15N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -38 -33 -28 -23 -18 -13 -8 -3 2 7 12 GWElevation(ft,NAVD88)WellID:5-39 Owner:ECCID Zone:Shallow Well Depth (ft):11N/APerf Int (ft): 0 10 20 30 40 50 60 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) 26 36 46 56 66 76 86 GWElevation(ft,NAVD88)WellID:Well #1 (4-54) Owner:ECCID Zone:Shallow Well Depth (ft):16585-165Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID: Well #11 (4-61-A) Owner:ECCID Zone: Shallow Well Depth (ft): 10050-100Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) 14 19 24 29 34 39 44 49 54 59 64 GW Elevation(ft,NAVD88) WellID: Well #13 Owner:ECCID Zone: Shallow Well Depth (ft): 185145-185Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) 0 5 10 15 20 25 30 35 40 45 50 GWElevation(ft,NAVD88)WellID:Well #6 (4-60) Owner:ECCID Zone:Shallow Well Depth (ft):5030-50Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -46 -41 -36 -31 -26 -21 -16 -11 -6 -1 4 GW Elevation (ft, NAVD88) WellID:1BMW-140 Owner:TODB Zone:Shallow Well Depth (ft):140100-130Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-38 -33 -28 -23 -18 -13 -8 -3 2 7 12 GW Elevation(ft,NAVD88) WellID: 4AMW-152 Owner:TODB Zone: Shallow Well Depth (ft): 152122-142Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -38 -33 -28 -23 -18 -13 -8 -3 2 7 12 GW Elevation(ft,NAVD88) WellID: 7MW-115 Owner:TODB Zone: Shallow Well Depth (ft): 11595-105Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -24 -19 -14 -9 -4 1 6 11 16 21 26 GWElevation(ft,NAVD88)WellID:USGS-380020121443901 Owner:USGS Zone:Shallow Well Depth (ft):66N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -53 -48 -43 -38 -33 -28 -23 -18 -13 -8 -3 GW Elevation (ft, NAVD88) WellID:01N04E20L001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-53 -48 -43 -38 -33 -28 -23 -18 -13 -8 -3 GW Elevation (ft, NAVD88) WellID: 01N04E20P001M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID: 01N04E20P002M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID:01N04E29C002M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -56 -51 -46 -41 -36 -31 -26 -21 -16 -11 -6 GW Elevation (ft, NAVD88) WellID:01N04E29D001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-57 -52 -47 -42 -37 -32 -27 -22 -17 -12 -7 GW Elevation (ft, NAVD88) WellID: 01N04E29P001M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -46 -41 -36 -31 -26 -21 -16 -11 -6 -1 4 GW Elevation (ft, NAVD88) WellID: 01N04E30G001M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-52 -47 -42 -37 -32 -27 -22 -17 -12 -7 -2 GW Elevation (ft, NAVD88) WellID:01N04E30H001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -52 -47 -42 -37 -32 -27 -22 -17 -12 -7 -2 GW Elevation (ft, NAVD88) WellID:01N04E30J001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID: 01N04E31H001M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 GW Elevation (ft, NAVD88) WellID: 01N04E31H002M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-53 -48 -43 -38 -33 -28 -23 -18 -13 -8 -3 GW Elevation (ft, NAVD88) WellID:01N04E31K001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID:01N04E31Q001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 GW Elevation (ft, NAVD88) WellID: 01N04E32D002M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 GW Elevation (ft, NAVD88) WellID: 01N04E32E001M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID:01S04E06L001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -53 -48 -43 -38 -33 -28 -23 -18 -13 -8 -3 GW Elevation (ft, NAVD88) WellID:01S04E06L002M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID: 01S04E06P002M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID: 01S04E06Q001M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-52 -47 -42 -37 -32 -27 -22 -17 -12 -7 -2 GW Elevation (ft, NAVD88) WellID:01S04E07A001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -44 -39 -34 -29 -24 -19 -14 -9 -4 1 6 GW Elevation (ft, NAVD88) WellID:01S04E07B001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID: 01S04E08A001M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -53 -48 -43 -38 -33 -28 -23 -18 -13 -8 -3 GW Elevation (ft, NAVD88) WellID: 01S04E08H001M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-49 -44 -39 -34 -29 -24 -19 -14 -9 -4 1 GW Elevation (ft, NAVD88) WellID:01S04E08K001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -53 -48 -43 -38 -33 -28 -23 -18 -13 -8 -3 GW Elevation (ft, NAVD88) WellID:01S04E08L001M Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-53 -48 -43 -38 -33 -28 -23 -18 -13 -8 -3 GW Elevation (ft, NAVD88) WellID: 01S04E08M001M Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) 10 15 20 25 30 35 40 45 50 55 60 GW Elevation(ft,NAVD88) WellID: 1S/4E 31P 5 Owner:N/A Zone: Shallow Well Depth (ft): 248-23Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID:378435N1215801W001 Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID:378826N1215755W001 Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID: 378957N1215652W001 Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -46 -41 -36 -31 -26 -21 -16 -11 -6 -1 4 GW Elevation (ft, NAVD88) WellID: 379050N1215730W001 Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-56 -51 -46 -41 -36 -31 -26 -21 -16 -11 -6 GW Elevation (ft, NAVD88) WellID:BD-1 Owner:N/A Zone:Shallow Well Depth (ft):10090-100Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -56 -51 -46 -41 -36 -31 -26 -21 -16 -11 -6 GW Elevation (ft, NAVD88) WellID:BD-2 Owner:N/A Zone:Shallow Well Depth (ft):10090-100Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-57 -52 -47 -42 -37 -32 -27 -22 -17 -12 -7 GW Elevation (ft, NAVD88) WellID: BD-3 Owner:N/A Zone: Shallow Well Depth (ft): 10090-100Perf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -53 -48 -43 -38 -33 -28 -23 -18 -13 -8 -3 GW Elevation (ft, NAVD88) WellID: BS-4 Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-56 -51 -46 -41 -36 -31 -26 -21 -16 -11 -6 GW Elevation (ft, NAVD88) WellID:BS-5 Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020DepthtoWater (ft) -56 -51 -46 -41 -36 -31 -26 -21 -16 -11 -6 GW Elevation (ft, NAVD88) WellID:BS-6 Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-57 -52 -47 -42 -37 -32 -27 -22 -17 -12 -7 GW Elevation (ft, NAVD88) WellID: VD-2 Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depthto Water (ft) -54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID: VS-10 Owner:N/A Zone: Shallow Well Depth (ft): 20N/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-54 -49 -44 -39 -34 -29 -24 -19 -14 -9 -4 GW Elevation (ft, NAVD88) WellID:VS-3 Owner:N/A Zone:Shallow Well Depth (ft):20N/APerf Int (ft): 0 20 40 60 80 100 120 140 160 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -87 -67 -47 -27 -7 13 33 53 73 GWElevation(ft,NAVD88)WellID:Brentwood MW-14 Deep Owner:CofB Zone:Deep Well Depth (ft):324284-315Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-47 -27 -7 13 33 53 73 GW Elevation(ft,NAVD88) WellID: Brentwood MW-14 Int. Owner:CofB Zone: Deep Well Depth (ft): 240200-210, 220-230Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -90 -70 -50 -30 -10 10 30 GW Elevation(ft,NAVD88) WellID: Creekside MW Owner:DWD Zone: Deep Well Depth (ft): 380230-240Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-82 -62 -42 -22 -2 18 38 GWElevation(ft,NAVD88)WellID:DIABLO WATER DISTRICT-Glen Park Well Owner:DWD Zone:Deep Well Depth (ft):315230-245, 260-300Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -124 -104 -84 -64 -44 -24 -4 GW Elevation (ft, NAVD88) WellID:DIABLO WATER DISTRICT-South Park Owner:DWD Zone:Deep Well Depth (ft):323204-264, 284-299Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-84 -64 -44 -24 -4 16 36 GW Elevation(ft,NAVD88) WellID: Glen Park MW Owner:DWD Zone: Deep Well Depth (ft): 300220-230, 260-290Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -125 -105 -85 -65 -45 -25 -5 GW Elevation (ft,NAVD88) WellID: Rock Island (Westside pump #2) Owner:DWD Zone: Deep Well Depth (ft): 320240-270, 284-292Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-90 -70 -50 -30 -10 10 30 GWElevation(ft,NAVD88)WellID:Stonecreek MW-300 Owner:DWD Zone:Deep Well Depth (ft):300230-240, 280-290Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -89 -69 -49 -29 -9 11 31 GWElevation(ft,NAVD88)WellID:Stonecreek MW-360 Owner:DWD Zone:Deep Well Depth (ft):360340-350Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-116 -96 -76 -56 -36 -16 4 GW Elevation (ft,NAVD88) WellID: 1BMW-343 Owner:TODB Zone: Deep Well Depth (ft): 343270-289, 309-338Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -108 -88 -68 -48 -28 -8 12 GW Elevation(ft,NAVD88) WellID: 4AMW-357 Owner:TODB Zone: Deep Well Depth (ft): 357307-347Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-113 -93 -73 -53 -33 -13 7 GW Elevation (ft, NAVD88) WellID:6MW-250 Owner:TODB Zone:Deep Well Depth (ft):250200-210, 230-240Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -113 -93 -73 -53 -33 -13 7 GW Elevation (ft, NAVD88) WellID:6MW-350 Owner:TODB Zone:Deep Well Depth (ft):350280-290, 330-340Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-113 -93 -73 -53 -33 -13 7 GW Elevation (ft,NAVD88) WellID: 6MW-410 Owner:TODB Zone: Deep Well Depth (ft): 410390-400Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -108 -88 -68 -48 -28 -8 12 GW Elevation(ft,NAVD88) WellID: 7MW-330 Owner:TODB Zone: Deep Well Depth (ft): 330310-320Perf Int (ft): 0 20 40 60 80 100 120 140 160 180 200 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-194 -174 -154 -134 -114 -94 -74 -54 -34 -14 6 GW Elevation (ft, NAVD88) WellID:TOWN OF DISCOVERY BAY-WELL 01B Owner:TODB Zone:Deep Well Depth (ft):350271-289, 308-340Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -111 -91 -71 -51 -31 -11 9 GW Elevation (ft, NAVD88) WellID:TOWN OF DISCOVERY BAY-WELL 02 Owner:TODB Zone:Deep Well Depth (ft):348245-335Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-105 -85 -65 -45 -25 -5 15 GW Elevation(ft,NAVD88) WellID: TOWN OF DISCOVERY BAY-WELL 04A Owner:TODB Zone: Deep Well Depth (ft): 357307-347Perf Int (ft): 0 20 40 60 80 100 120 140 160 180 200 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -184 -164 -144 -124 -104 -84 -64 -44 -24 -4 16 GW Elevation(ft,NAVD88) WellID: TOWN OF DISCOVERY BAY-WELL 05A Owner:TODB Zone: Deep Well Depth (ft): 357251-281, 307-347Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-112 -92 -72 -52 -32 -12 8 GW Elevation (ft, NAVD88) WellID:TOWN OF DISCOVERY BAY-WELL 06 Owner:TODB Zone:Deep Well Depth (ft):360270-295, 305-350Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -113 -93 -73 -53 -33 -13 7 GW Elevation (ft, NAVD88) WellID:TOWN OF DISCOVERY BAY-WELL 07 Owner:TODB Zone:Deep Well Depth (ft):346282-292Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-90 -70 -50 -30 -10 10 30 GW Elevation(ft,NAVD88) WellID: KNIGHTSEN COMMUNITY WATER SYSTEM-Well Head Owner:KNIGHTSEN COMMUNITY Zone: Deep Well Depth (ft): 305235-255, 275-295Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -90 -70 -50 -30 -10 10 30 GW Elevation(ft,NAVD88) WellID: KNIGHTSEN ELEMENTARY SCHOOL-WELL 3 Owner:KNIGHTSEN ELEMENTAR Zone: Deep Well Depth (ft): 415395-415Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-126 -106 -86 -66 -46 -26 -6 GW Elevation (ft, NAVD88) WellID:Bethel Island (Sugar Barge Marina-Well Head) Owner:SUGAR BARGE MARINA Zone:Deep Well Depth (ft):333317-333Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -75 -55 -35 -15 5 25 45 GWElevation(ft,NAVD88)WellID:2 Casing Owner:BBID Zone:Composite Well Depth (ft):16371-163Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -88 -68 -48 -28 -8 12 32 GWElevation(ft,NAVD88)WellID: 6 Byer Owner:BBID Zone: Composite Well Depth (ft): 185N/APerf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -47 -27 -7 13 33 53 73 GW Elevation(ft,NAVD88) WellID: Brentwood MW-14 Shallow Owner:CofB Zone: Composite Well Depth (ft): 154114-144Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-91 -71 -51 -31 -11 9 29 GWElevation(ft,NAVD88)WellID:Knightsen School Irrigation (#2) Owner:DWD Zone:Composite Well Depth (ft):230167-191, 210-230Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -89 -69 -49 -29 -9 11 31 GWElevation(ft,NAVD88)WellID:Stonecreek MW-160 Owner:DWD Zone:Composite Well Depth (ft):160100-110, 140-150Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-93 -73 -53 -33 -13 7 27 GW Elevation(ft,NAVD88) WellID: Well #14 Owner:ECCID Zone: Composite Well Depth (ft): 330200-300Perf Int (ft): 0 20 40 60 80 100 120 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -25 -5 15 35 55 75 95 GWElevation(ft,NAVD88)WellID: Well #3 (4-55) Owner:ECCID Zone: Composite Well Depth (ft): 365113-197, 281-365Perf Int (ft): 0 20 40 60 80 100 120 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -30 -10 10 30 50 70 90 GWElevation(ft,NAVD88)WellID:Well #4 (5-62) Owner:ECCID Zone:Composite Well Depth (ft):20068-125, 175-195Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -33 -13 7 27 47 67 87 GWElevation(ft,NAVD88)WellID:Well #4 Old (4-56) Owner:ECCID Zone:Composite Well Depth (ft):20368-125, 175-195Perf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -59 -39 -19 1 21 41 61 GWElevation(ft,NAVD88)WellID: Well #5 (4-57) Owner:ECCID Zone: Composite Well Depth (ft): 290115-125, 170-175Perf Int (ft): 0 20 40 60 80 100 120 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -23 -3 17 37 57 77 97 GWElevation(ft,NAVD88)WellID: Well #9 (4-58) Owner:ECCID Zone: Composite Well Depth (ft): 21090-106, 118-126,Perf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-80 -60 -40 -20 0 20 40 GWElevation(ft,NAVD88)WellID:10 SM2 Owner:BBID Zone:Unknown Well Depth (ft):N/AN/APerf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -78 -58 -38 -18 2 22 42 GWElevation(ft,NAVD88)WellID:10A Taylor Owner:BBID Zone:Unknown Well Depth (ft):N/AN/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-83 -63 -43 -23 -3 17 37 GW Elevation(ft,NAVD88) WellID: 10C Marsh Owner:BBID Zone: Unknown Well Depth (ft): N/AN/APerf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -79 -59 -39 -19 1 21 41 GW Elevation(ft,NAVD88) WellID: 11 TN1 Owner:BBID Zone: Unknown Well Depth (ft): N/AN/APerf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-60 -40 -20 0 20 40 60 GWElevation(ft,NAVD88)WellID:12 TN2 Owner:BBID Zone:Unknown Well Depth (ft):N/AN/APerf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -79 -59 -39 -19 1 21 41 GWElevation(ft,NAVD88)WellID:13 M Owner:BBID Zone:Unknown Well Depth (ft):N/AN/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-90 -70 -50 -30 -10 10 30 GW Elevation(ft,NAVD88) WellID: 14 GNO Owner:BBID Zone: Unknown Well Depth (ft): N/AN/APerf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -46 -26 -6 14 34 54 74 GW Elevation(ft,NAVD88) WellID: 7 Hoffman 1 Owner:BBID Zone: Unknown Well Depth (ft): N/AN/APerf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-69 -49 -29 -9 11 31 51 GWElevation(ft,NAVD88)WellID:8 Casing 2 Owner:BBID Zone:Unknown Well Depth (ft):N/AN/APerf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -82 -62 -42 -22 -2 18 38 GWElevation(ft,NAVD88)WellID:9 SM1 Owner:BBID Zone:Unknown Well Depth (ft):N/AN/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft)-87 -67 -47 -27 -7 13 33 GW Elevation(ft,NAVD88) WellID: 9d Abreu Owner:BBID Zone: Unknown Well Depth (ft): N/AN/APerf Int (ft): 0 20 40 60 80 100 120 1990199219941996199820002002200420062008201020122014201620182020Depth to Water (ft) -82 -62 -42 -22 -2 18 38 GW Elevation(ft,NAVD88) WellID: 9e Hagen Owner:BBID Zone: Unknown Well Depth (ft): N/AN/APerf Int (ft): 0 20 40 60 80 100 120 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -31 -11 9 29 49 69 89 GWElevation(ft,NAVD88)WellID:Anderson (4.66) Owner:ECCID Zone:Unknown Well Depth (ft):N/AN/APerf Int (ft): 0 20 40 60 80 100 120 1950 1960 1970 1980 1990 2000 2010 2020Depth to Water (ft) -80 -60 -40 -20 0 20 40 GWElevation(ft,NAVD88)WellID:Well #2 (5-30) Owner:ECCID Zone:Unknown Well Depth (ft):N/AN/APerf Int (ft): Transducer Water Level MeasurementManual Water Level Measurement 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:SL0601327206-EW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:SL0601327206-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:SL0601327206-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -29 -19 -9 1 11 21 31 41 51 61 71 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 4 9 14 19 24 29 34 39 44 49 54 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 4 9 14 19 24 29 34 39 44 49 54 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 6 11 16 21 26 31 36 41 46 51 56 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-18 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-19 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -30 -20 -10 0 10 20 30 40 50 60 70 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -18 -8 2 12 22 32 42 52 62 72 82 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-22 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -28 -18 -8 2 12 22 32 42 52 62 72 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-23 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -30 -20 -10 0 10 20 30 40 50 60 70 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-25 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -30 -20 -10 0 10 20 30 40 50 60 70 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -23 -13 -3 7 17 27 37 47 57 67 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -26 -16 -6 4 14 24 34 44 54 64 74 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -19 -9 1 11 21 31 41 51 61 71 81 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -18 -8 2 12 22 32 42 52 62 72 82 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -29 -19 -9 1 11 21 31 41 51 61 71 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -26 -16 -6 4 14 24 34 44 54 64 74 GWElevation(ft,NAVD88)WellID:SL0601346154-94MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -28 -23 -18 -13 -8 -3 2 7 12 17 22 GWElevation(ft,NAVD88)WellID:SL0601394831-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:SL0601394831-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:SL0601394831-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:SL0601394831-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -30 -25 -20 -15 -10 -5 0 5 10 15 20 GWElevation(ft,NAVD88)WellID:SL186102968-7EW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -30 -25 -20 -15 -10 -5 0 5 10 15 20 GWElevation(ft,NAVD88)WellID:SL186102968-7EW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -30 -25 -20 -15 -10 -5 0 5 10 15 20 GWElevation(ft,NAVD88)WellID:SL186102968-7EW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -28 -23 -18 -13 -8 -3 2 7 12 17 22 GWElevation(ft,NAVD88)WellID:SL186102968-7EW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -28 -23 -18 -13 -8 -3 2 7 12 17 22 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -26 -21 -16 -11 -6 -1 4 9 14 19 24 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -24 -19 -14 -9 -4 1 6 11 16 21 26 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -30 -25 -20 -15 -10 -5 0 5 10 15 20 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -28 -23 -18 -13 -8 -3 2 7 12 17 22 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -28 -23 -18 -13 -8 -3 2 7 12 17 22 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -26 -21 -16 -11 -6 -1 4 9 14 19 24 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:SL186102968-7MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID:SL20210828-903B1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -16 -11 -6 -1 4 9 14 19 24 29 34 GWElevation(ft,NAVD88)WellID:SL205032990-W-01 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:SL205032990-W-02 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -30 -25 -20 -15 -10 -5 0 5 10 15 20 GWElevation(ft,NAVD88)WellID:SL205032990-W-03 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -10 -5 0 5 10 15 20 25 30 35 GWElevation(ft,NAVD88)WellID:SL205032990-W-04 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -13 -8 -3 2 7 12 17 22 27 32 37 GWElevation(ft,NAVD88)WellID:SL205032990-W-05 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -17 -12 -7 -2 3 8 13 18 23 28 33 GWElevation(ft,NAVD88)WellID:SL205032990-W-06 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -20 -15 -10 -5 0 5 10 15 20 25 30 GWElevation(ft,NAVD88)WellID:SL205032990-W-07 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -17 -12 -7 -2 3 8 13 18 23 28 33 GWElevation(ft,NAVD88)WellID:SL205032990-W-08 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:SL205032990-W-09 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -14 -9 -4 1 6 11 16 21 26 31 36 GWElevation(ft,NAVD88)WellID:SL205032990-W-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:SL205032990-W-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -29 -24 -19 -14 -9 -4 1 6 11 16 21 GWElevation(ft,NAVD88)WellID:SL205032990-W-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -30 -25 -20 -15 -10 -5 0 5 10 15 20 GWElevation(ft,NAVD88)WellID:SL205032990-W-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -39 -34 -29 -24 -19 -14 -9 -4 1 6 11 GWElevation(ft,NAVD88)WellID:SL205032990-W-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:SL205032990-W-15 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -29 -24 -19 -14 -9 -4 1 6 11 16 21 GWElevation(ft,NAVD88)WellID:SL205032990-W-16 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -30 -25 -20 -15 -10 -5 0 5 10 15 20 GWElevation(ft,NAVD88)WellID:SL205032990-W-17 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -29 -24 -19 -14 -9 -4 1 6 11 16 21 GWElevation(ft,NAVD88)WellID:SL205032990-W-18 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:SL205032990-W-19 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -38 -33 -28 -23 -18 -13 -8 -3 2 7 12 GWElevation(ft,NAVD88)WellID:SL205032990-W-20 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:SL205032990-W-21 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -10 -5 0 5 10 15 20 25 30 35 GWElevation(ft,NAVD88)WellID:SL205032990-W-22 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:SL205032990-W-23 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -28 -23 -18 -13 -8 -3 2 7 12 17 22 GWElevation(ft,NAVD88)WellID:SL205032990-W-24 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -10 -5 0 5 10 15 20 25 30 35 GWElevation(ft,NAVD88)WellID:SL205032990-W-25 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -11 -6 -1 4 9 14 19 24 29 34 39 GWElevation(ft,NAVD88)WellID:SL205032990-W-26 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 GWElevation(ft,NAVD88)WellID:SL205032990-W-27 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 GWElevation(ft,NAVD88)WellID:SL205032990-W-28 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -39 -34 -29 -24 -19 -14 -9 -4 1 6 11 GWElevation(ft,NAVD88)WellID:SL205032990-W-29 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:SL205032990-W-30 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:SL205032990-W-31 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:SL205032990-W-32 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:SL205032990-W-33 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -28 -23 -18 -13 -8 -3 2 7 12 17 22 GWElevation(ft,NAVD88)WellID:SL205032990-W-34 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -28 -23 -18 -13 -8 -3 2 7 12 17 22 GWElevation(ft,NAVD88)WellID:SL205032990-W-35 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -28 -23 -18 -13 -8 -3 2 7 12 17 22 GWElevation(ft,NAVD88)WellID:SL205032990-W-36 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -39 -34 -29 -24 -19 -14 -9 -4 1 6 11 GWElevation(ft,NAVD88)WellID:SL205032990-W-37 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -39 -34 -29 -24 -19 -14 -9 -4 1 6 11 GWElevation(ft,NAVD88)WellID:SL205032990-W-38 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID:SL205032990-W-39 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:SL205032990-W-40 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 9 19 29 39 49 59 69 79 89 99 109 GWElevation (ft, NAVD88) WellID:SL205092993-MW-12A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 8 18 28 38 48 58 68 78 88 98 108 GWElevation(ft,NAVD88)WellID:SL205092993-MW-14A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 9 19 29 39 49 59 69 79 89 99 109 GW Elevation (ft, NAVD88) WellID:SL205092993-MW-17A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 10 20 30 40 50 60 70 80 90 100 110 GWElevation(ft,NAVD88)WellID:SL205092993-MW-6A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 9 19 29 39 49 59 69 79 89 99 109 GWElevation (ft, NAVD88) WellID:SL205092993-MW-8A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -1 4 9 14 19 24 29 34 39 44 49 GWElevation(ft,NAVD88)WellID:T0601300676-MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID:T0601300676-MW-16A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID:T0601300676-MW-16B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID:T0601300676-MW-16C Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID:T0601300676-MW-17 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 0 5 10 15 20 25 30 35 40 45 50 GWElevation(ft,NAVD88)WellID:T0601300676-MW-22 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 0 5 10 15 20 25 30 35 40 45 50 GWElevation(ft,NAVD88)WellID:T0601300676-MW-22C Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID:T0601300676-MW-23 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 2 7 12 17 22 27 32 37 42 47 52 GWElevation(ft,NAVD88)WellID:T0601300676-MW-24 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 2 7 12 17 22 27 32 37 42 47 52 GWElevation(ft,NAVD88)WellID:T0601300676-MW-25 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 2 7 12 17 22 27 32 37 42 47 52 GWElevation(ft,NAVD88)WellID:T0601300676-MW-25B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID:T0601300676-MW-26 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID:T0601300676-MW-26B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 0 5 10 15 20 25 30 35 40 45 50 GWElevation(ft,NAVD88)WellID:T0601300676-MW-28 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 0 5 10 15 20 25 30 35 40 45 50 GWElevation(ft,NAVD88)WellID:T0601300676-MW-28C Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 0 5 10 15 20 25 30 35 40 45 50 GWElevation(ft,NAVD88)WellID:T0601300676-MW-29 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 1 6 11 16 21 26 31 36 41 46 51 GWElevation(ft,NAVD88)WellID:T0601300676-MW-30A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 3 8 13 18 23 28 33 38 43 48 53 GWElevation(ft,NAVD88)WellID:T0601300676-MW-31A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 3 8 13 18 23 28 33 38 43 48 53 GWElevation(ft,NAVD88)WellID:T0601300676-MW-32D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID:T0601300676-MW-5A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 5 10 15 20 25 30 35 40 45 50 55 GWElevation(ft,NAVD88)WellID:T0601300676-MW-5B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 4 9 14 19 24 29 34 39 44 49 54 GWElevation(ft,NAVD88)WellID:T0601300676-MW-5C Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 3 8 13 18 23 28 33 38 43 48 53 GWElevation(ft,NAVD88)WellID:T0601300676-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601300744-W-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601300744-W-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601300744-W-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601300744-W-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 19 24 29 34 39 44 49 54 59 64 69 GWElevation(ft,NAVD88)WellID:T0601300744-W-5B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 17 22 27 32 37 42 47 52 57 62 67 GWElevation(ft,NAVD88)WellID:T0601300744-W-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 19 24 29 34 39 44 49 54 59 64 69 GWElevation(ft,NAVD88)WellID:T0601300744-W-7B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 19 24 29 34 39 44 49 54 59 64 69 GWElevation(ft,NAVD88)WellID:T0601300744-W-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -17 -12 -7 -2 3 8 13 18 23 28 GWElevation(ft,NAVD88)WellID:T0601300747-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:T0601300747-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -17 -12 -7 -2 3 8 13 18 23 28 GWElevation(ft,NAVD88)WellID:T0601300747-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -23 -18 -13 -8 -3 2 7 12 17 22 27 GWElevation(ft,NAVD88)WellID:T0601300747-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -23 -18 -13 -8 -3 2 7 12 17 22 27 GWElevation(ft,NAVD88)WellID:T0601300747-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -23 -18 -13 -8 -3 2 7 12 17 22 27 GWElevation(ft,NAVD88)WellID:T0601300747-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -17 -12 -7 -2 3 8 13 18 23 28 GWElevation(ft,NAVD88)WellID:T0601300747-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -17 -12 -7 -2 3 8 13 18 23 28 GWElevation(ft,NAVD88)WellID:T0601300747-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -23 -18 -13 -8 -3 2 7 12 17 22 27 GWElevation(ft,NAVD88)WellID:T0601300747-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -17 -12 -7 -2 3 8 13 18 23 28 GWElevation(ft,NAVD88)WellID:T0601300747-PZ-01 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -17 -12 -7 -2 3 8 13 18 23 28 GWElevation(ft,NAVD88)WellID:T0601300747-PZ-02 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -17 -12 -7 -2 3 8 13 18 23 28 GWElevation(ft,NAVD88)WellID:T0601300747-PZ-03 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -10 -5 0 5 10 15 20 25 30 35 GWElevation(ft,NAVD88)WellID:T0601300756-EW100 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -14 -9 -4 1 6 11 16 21 26 31 36 GWElevation(ft,NAVD88)WellID:T0601300756-EW101 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -16 -11 -6 -1 4 9 14 19 24 29 34 GWElevation(ft,NAVD88)WellID:T0601300756-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300756-MW-10L Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -14 -9 -4 1 6 11 16 21 26 31 36 GWElevation(ft,NAVD88)WellID:T0601300756-MW-10U Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -10 -5 0 5 10 15 20 25 30 35 40 GWElevation(ft,NAVD88)WellID:T0601300756-MW-11L Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -13 -8 -3 2 7 12 17 22 27 32 37 GWElevation(ft,NAVD88)WellID:T0601300756-MW-12L Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -13 -8 -3 2 7 12 17 22 27 32 37 GWElevation(ft,NAVD88)WellID:T0601300756-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -13 -8 -3 2 7 12 17 22 27 32 37 GWElevation(ft,NAVD88)WellID:T0601300756-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -10 -5 0 5 10 15 20 25 30 35 GWElevation(ft,NAVD88)WellID:T0601300756-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -10 -5 0 5 10 15 20 25 30 35 GWElevation(ft,NAVD88)WellID:T0601300756-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -10 -5 0 5 10 15 20 25 30 35 40 GWElevation(ft,NAVD88)WellID:T0601300756-MW-6A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300756-MW-7A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601300756-MW-8U Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300756-MW-9U Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-13S Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-14D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-15 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-16 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-17 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601300764-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID:T0601300764-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -38 -33 -28 -23 -18 -13 -8 -3 2 7 12 GWElevation(ft,NAVD88)WellID:T0601300764-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID:T0601300764-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300764-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300766-IW10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300766-IW9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 28 33 38 43 48 53 58 63 68 73 78 GWElevation(ft,NAVD88)WellID:T0601300766-MW1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 28 33 38 43 48 53 58 63 68 73 78 GWElevation(ft,NAVD88)WellID:T0601300766-MW2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300766-MW3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300766-MW4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300766-MW5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300766-MW6A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300766-MW6B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300766-MW7A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300766-MW7B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300766-MW8A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 25 30 35 40 45 50 55 60 65 70 75 GWElevation(ft,NAVD88)WellID:T0601300766-MW8B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300766-MW8C Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -12 -2 8 18 28 38 48 58 68 78 GWElevation(ft,NAVD88)WellID:T0601300768-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -12 -2 8 18 28 38 48 58 68 78 GWElevation(ft,NAVD88)WellID:T0601300768-MW-1R Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -11 -1 9 19 29 39 49 59 69 79 GWElevation(ft,NAVD88)WellID:T0601300768-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -12 -2 8 18 28 38 48 58 68 78 GWElevation(ft,NAVD88)WellID:T0601300768-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -12 -2 8 18 28 38 48 58 68 78 GWElevation(ft,NAVD88)WellID:T0601300768-MW-3R Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -11 -1 9 19 29 39 49 59 69 79 GWElevation(ft,NAVD88)WellID:T0601300768-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -23 -13 -3 7 17 27 37 47 57 67 77 GWElevation(ft,NAVD88)WellID:T0601300768-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -12 -2 8 18 28 38 48 58 68 78 GWElevation(ft,NAVD88)WellID:T0601300768-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -10 -5 0 5 10 15 20 25 30 35 GWElevation(ft,NAVD88)WellID:T0601300772-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -14 -9 -4 1 6 11 16 21 26 31 36 GWElevation(ft,NAVD88)WellID:T0601300772-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -11 -6 -1 4 9 14 19 24 29 34 39 GWElevation(ft,NAVD88)WellID:T0601300772-MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -13 -8 -3 2 7 12 17 22 27 32 37 GWElevation(ft,NAVD88)WellID:T0601300772-MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -14 -9 -4 1 6 11 16 21 26 31 36 GWElevation(ft,NAVD88)WellID:T0601300772-MW-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -16 -11 -6 -1 4 9 14 19 24 29 34 GWElevation(ft,NAVD88)WellID:T0601300772-MW-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -17 -12 -7 -2 3 8 13 18 23 28 33 GWElevation(ft,NAVD88)WellID:T0601300772-MW-15 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -18 -13 -8 -3 2 7 12 17 22 27 32 GWElevation(ft,NAVD88)WellID:T0601300772-MW-16 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -18 -13 -8 -3 2 7 12 17 22 27 32 GWElevation(ft,NAVD88)WellID:T0601300772-MW-17 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -14 -9 -4 1 6 11 16 21 26 31 36 GWElevation(ft,NAVD88)WellID:T0601300772-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -13 -8 -3 2 7 12 17 22 27 32 37 GWElevation(ft,NAVD88)WellID:T0601300772-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -14 -9 -4 1 6 11 16 21 26 31 36 GWElevation(ft,NAVD88)WellID:T0601300772-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -10 -5 0 5 10 15 20 25 30 35 GWElevation(ft,NAVD88)WellID:T0601300772-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -10 -5 0 5 10 15 20 25 30 35 GWElevation(ft,NAVD88)WellID:T0601300772-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -14 -9 -4 1 6 11 16 21 26 31 36 GWElevation(ft,NAVD88)WellID:T0601300772-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -14 -9 -4 1 6 11 16 21 26 31 36 GWElevation(ft,NAVD88)WellID:T0601300772-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -13 -8 -3 2 7 12 17 22 27 32 37 GWElevation(ft,NAVD88)WellID:T0601300772-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601300775-EW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601300775-EW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601300775-EW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300775-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601300775-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300775-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601300775-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300775-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601300775-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 GWElevation(ft,NAVD88)WellID:T0601300776-KMW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 GWElevation(ft,NAVD88)WellID:T0601300776-KMW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -38 -33 -28 -23 -18 -13 -8 -3 2 7 12 GWElevation(ft,NAVD88)WellID:T0601300776-KMW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -43 -38 -33 -28 -23 -18 -13 -8 -3 2 7 GW Elevation (ft, NAVD88) WellID:T0601300776-KMW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -43 -38 -33 -28 -23 -18 -13 -8 -3 2 7 GW Elevation (ft, NAVD88) WellID:T0601300776-MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601300776-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 GWElevation(ft,NAVD88)WellID:T0601300776-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300776-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -39 -34 -29 -24 -19 -14 -9 -4 1 6 11 GWElevation(ft,NAVD88)WellID:T0601300776-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601300776-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 GWElevation(ft,NAVD88)WellID:T0601300776-MW-7A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -43 -38 -33 -28 -23 -18 -13 -8 -3 2 7 GW Elevation (ft, NAVD88) WellID:T0601300776-SG-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300780-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601300780-MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -11 -6 -1 4 9 14 19 24 29 34 39 GWElevation(ft,NAVD88)WellID:T0601300780-MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -8 -3 2 7 12 17 22 27 32 37 42 GWElevation(ft,NAVD88)WellID:T0601300780-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300781-DW-1A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300781-DW-1B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300781-DW-2A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300781-DW-2B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300781-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300781-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300781-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601300781-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300781-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300781-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300781-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300781-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300781-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -3 2 7 12 17 22 27 32 37 42 47 GWElevation(ft,NAVD88)WellID:T0601300782-EW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -4 1 6 11 16 21 26 31 36 41 46 GWElevation(ft,NAVD88)WellID:T0601300782-EW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -4 1 6 11 16 21 26 31 36 41 46 GWElevation(ft,NAVD88)WellID:T0601300782-EW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -3 2 7 12 17 22 27 32 37 42 47 GWElevation(ft,NAVD88)WellID:T0601300782-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -2 3 8 13 18 23 28 33 38 43 48 GWElevation(ft,NAVD88)WellID:T0601300782-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -1 4 9 14 19 24 29 34 39 44 49 GWElevation(ft,NAVD88)WellID:T0601300782-MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -5 0 5 10 15 20 25 30 35 40 45 GWElevation(ft,NAVD88)WellID:T0601300782-MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 1 6 11 16 21 26 31 36 41 46 51 GWElevation(ft,NAVD88)WellID:T0601300782-MW-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 1 6 11 16 21 26 31 36 41 46 51 GWElevation(ft,NAVD88)WellID:T0601300782-MW-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -4 1 6 11 16 21 26 31 36 41 46 GWElevation(ft,NAVD88)WellID:T0601300782-MW-15 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -3 2 7 12 17 22 27 32 37 42 47 GWElevation(ft,NAVD88)WellID:T0601300782-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -1 4 9 14 19 24 29 34 39 44 49 GWElevation(ft,NAVD88)WellID:T0601300782-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -4 1 6 11 16 21 26 31 36 41 46 GWElevation(ft,NAVD88)WellID:T0601300782-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300782-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -7 -2 3 8 13 18 23 28 33 38 43 GWElevation(ft,NAVD88)WellID:T0601300782-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -3 2 7 12 17 22 27 32 37 42 47 GWElevation(ft,NAVD88)WellID:T0601300782-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -1 4 9 14 19 24 29 34 39 44 49 GWElevation(ft,NAVD88)WellID:T0601300782-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -4 1 6 11 16 21 26 31 36 41 46 GWElevation(ft,NAVD88)WellID:T0601300782-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 25 30 35 40 45 50 55 60 65 70 75 GWElevation(ft,NAVD88)WellID:T0601300783-DW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 25 30 35 40 45 50 55 60 65 70 75 GWElevation(ft,NAVD88)WellID:T0601300783-DW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300783-DW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 23 28 33 38 43 48 53 58 63 68 73 GWElevation(ft,NAVD88)WellID:T0601300783-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300783-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 24 29 34 39 44 49 54 59 64 69 74 GWElevation(ft,NAVD88)WellID:T0601300783-MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 24 29 34 39 44 49 54 59 64 69 74 GWElevation(ft,NAVD88)WellID:T0601300783-MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 23 28 33 38 43 48 53 58 63 68 73 GWElevation(ft,NAVD88)WellID:T0601300783-MW-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 24 29 34 39 44 49 54 59 64 69 74 GWElevation(ft,NAVD88)WellID:T0601300783-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 24 29 34 39 44 49 54 59 64 69 74 GWElevation(ft,NAVD88)WellID:T0601300783-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 23 28 33 38 43 48 53 58 63 68 73 GWElevation(ft,NAVD88)WellID:T0601300783-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 23 28 33 38 43 48 53 58 63 68 73 GWElevation(ft,NAVD88)WellID:T0601300783-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 25 30 35 40 45 50 55 60 65 70 75 GWElevation(ft,NAVD88)WellID:T0601300783-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 23 28 33 38 43 48 53 58 63 68 73 GWElevation(ft,NAVD88)WellID:T0601300783-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300783-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 23 28 33 38 43 48 53 58 63 68 73 GWElevation(ft,NAVD88)WellID:T0601300783-SVE-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 24 29 34 39 44 49 54 59 64 69 74 GWElevation(ft,NAVD88)WellID:T0601300783-SVE-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300784-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300784-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300784-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -42 -37 -32 -27 -22 -17 -12 -7 -2 3 8 GW Elevation (ft, NAVD88) WellID:T0601300788-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -42 -37 -32 -27 -22 -17 -12 -7 -2 3 8 GW Elevation (ft, NAVD88) WellID:T0601300788-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -42 -37 -32 -27 -22 -17 -12 -7 -2 3 8 GW Elevation (ft, NAVD88) WellID:T0601300788-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601300788-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -43 -38 -33 -28 -23 -18 -13 -8 -3 2 7 GW Elevation (ft, NAVD88) WellID:T0601300788-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601300788-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300790-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300790-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300790-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300790-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601300790-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601300790-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -7 -2 3 8 13 18 23 28 33 38 43 GWElevation(ft,NAVD88)WellID:T0601300800-BW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -58 -48 -38 -28 -18 -8 2 12 22 32 42 GWElevation(ft,NAVD88)WellID:T0601300800-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -8 -3 2 7 12 17 22 27 32 37 42 GWElevation(ft,NAVD88)WellID:T0601300800-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300800-MW-4A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300800-MW-4B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -8 -3 2 7 12 17 22 27 32 37 42 GWElevation(ft,NAVD88)WellID:T0601300800-MW-5B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -11 -6 -1 4 9 14 19 24 29 34 39 GWElevation(ft,NAVD88)WellID:T0601300800-MW-6A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -11 -6 -1 4 9 14 19 24 29 34 39 GWElevation(ft,NAVD88)WellID:T0601300800-MW-6B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -8 -3 2 7 12 17 22 27 32 37 42 GWElevation(ft,NAVD88)WellID:T0601300800-MW-7B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -8 -3 2 7 12 17 22 27 32 37 42 GWElevation(ft,NAVD88)WellID:T0601300800-MW-7BL Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300800-MW-8A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300800-MW-8BL Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 17 22 27 32 37 42 47 52 57 62 67 GWElevation(ft,NAVD88)WellID:T0601300802-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601300802-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 17 22 27 32 37 42 47 52 57 62 67 GWElevation(ft,NAVD88)WellID:T0601300802-MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 14 19 24 29 34 39 44 49 54 59 64 GWElevation(ft,NAVD88)WellID:T0601300802-MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 15 20 25 30 35 40 45 50 55 60 65 GWElevation(ft,NAVD88)WellID:T0601300802-MW-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 16 21 26 31 36 41 46 51 56 61 66 GWElevation(ft,NAVD88)WellID:T0601300802-MW-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 17 22 27 32 37 42 47 52 57 62 67 GWElevation(ft,NAVD88)WellID:T0601300802-MW-15D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 15 20 25 30 35 40 45 50 55 60 65 GWElevation(ft,NAVD88)WellID:T0601300802-MW-16D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 15 20 25 30 35 40 45 50 55 60 65 GWElevation(ft,NAVD88)WellID:T0601300802-MW-17D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601300802-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 16 21 26 31 36 41 46 51 56 61 66 GWElevation(ft,NAVD88)WellID:T0601300802-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 16 21 26 31 36 41 46 51 56 61 66 GWElevation(ft,NAVD88)WellID:T0601300802-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 15 20 25 30 35 40 45 50 55 60 65 GWElevation(ft,NAVD88)WellID:T0601300802-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 14 19 24 29 34 39 44 49 54 59 64 GWElevation(ft,NAVD88)WellID:T0601300802-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 15 20 25 30 35 40 45 50 55 60 65 GWElevation(ft,NAVD88)WellID:T0601300802-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 17 22 27 32 37 42 47 52 57 62 67 GWElevation(ft,NAVD88)WellID:T0601300802-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601300802-MW-9D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STEW-23 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300803-STEW-24 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STEW-25 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STEW-26 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -29 -24 -19 -14 -9 -4 1 6 11 16 21 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-17 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-18 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-19 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-20 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-21 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-22 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-27 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -25 -20 -15 -10 -5 0 5 10 15 20 25 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-28 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-29 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-30 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-31 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-32 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -27 -22 -17 -12 -7 -2 3 8 13 18 23 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-33 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -10 -5 0 5 10 15 20 25 30 35 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-34 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -20 -15 -10 -5 0 5 10 15 20 25 30 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-35 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-36 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STMW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -33 -28 -23 -18 -13 -8 -3 2 7 12 17 GWElevation(ft,NAVD88)WellID:T0601300803-STMWD-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -29 -24 -19 -14 -9 -4 1 6 11 16 21 GWElevation(ft,NAVD88)WellID:T0601300803-STMWD-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300803-STMWD-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STMWD-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -32 -27 -22 -17 -12 -7 -2 3 8 13 18 GWElevation(ft,NAVD88)WellID:T0601300803-STMWD-15 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300803-STMWD-16 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -31 -26 -21 -16 -11 -6 -1 4 9 14 19 GWElevation(ft,NAVD88)WellID:T0601300803-STMWD-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 28 33 38 43 48 53 58 63 68 73 78 GWElevation(ft,NAVD88)WellID:T0601300804-EW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300804-EW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300804-EW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300804-EW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300804-EW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300804-EW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 29 34 39 44 49 54 59 64 69 74 79 GWElevation(ft,NAVD88)WellID:T0601300804-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300804-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 28 33 38 43 48 53 58 63 68 73 78 GWElevation(ft,NAVD88)WellID:T0601300804-MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300804-MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300804-MW-12A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300804-MW-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 25 30 35 40 45 50 55 60 65 70 75 GWElevation(ft,NAVD88)WellID:T0601300804-MW-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300804-MW-15B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300804-MW-16B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 28 33 38 43 48 53 58 63 68 73 78 GWElevation(ft,NAVD88)WellID:T0601300804-MW-17B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 28 33 38 43 48 53 58 63 68 73 78 GWElevation(ft,NAVD88)WellID:T0601300804-MW-2A Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300804-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300804-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 28 33 38 43 48 53 58 63 68 73 78 GWElevation(ft,NAVD88)WellID:T0601300804-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 27 32 37 42 47 52 57 62 67 72 77 GWElevation(ft,NAVD88)WellID:T0601300804-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300804-MW-6D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300804-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300804-MW-7D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 24 29 34 39 44 49 54 59 64 69 74 GWElevation(ft,NAVD88)WellID:T0601300804-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 26 31 36 41 46 51 56 61 66 71 76 GWElevation(ft,NAVD88)WellID:T0601300804-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300807-IP-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300807-IP-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300807-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300807-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -8 -3 2 7 12 17 22 27 32 37 42 GWElevation(ft,NAVD88)WellID:T0601300807-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -10 -5 0 5 10 15 20 25 30 35 40 GWElevation(ft,NAVD88)WellID:T0601300807-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -8 -3 2 7 12 17 22 27 32 37 42 GWElevation(ft,NAVD88)WellID:T0601300807-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -8 -3 2 7 12 17 22 27 32 37 42 GWElevation(ft,NAVD88)WellID:T0601300807-MW-5B Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -8 -3 2 7 12 17 22 27 32 37 42 GWElevation(ft,NAVD88)WellID:T0601300807-MW-5C Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300807-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300807-OW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300807-OW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300807-S-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -11 -6 -1 4 9 14 19 24 29 34 39 GWElevation(ft,NAVD88)WellID:T0601300807-S-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -9 -4 1 6 11 16 21 26 31 36 41 GWElevation(ft,NAVD88)WellID:T0601300807-S-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -10 -5 0 5 10 15 20 25 30 35 40 GWElevation(ft,NAVD88)WellID:T0601300807-S-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -10 -5 0 5 10 15 20 25 30 35 40 GWElevation(ft,NAVD88)WellID:T0601300807-S-15 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -10 -5 0 5 10 15 20 25 30 35 40 GWElevation(ft,NAVD88)WellID:T0601300807-S-17 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -8 -3 2 7 12 17 22 27 32 37 42 GWElevation(ft,NAVD88)WellID:T0601300807-S-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -10 -5 0 5 10 15 20 25 30 35 40 GWElevation(ft,NAVD88)WellID:T0601300807-S-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID:T0601300809-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-102 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-103 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID:T0601300809-MW-104 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID:T0601300809-MW-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID:T0601300809-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID:T0601300809-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601300809-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -36 -31 -26 -21 -16 -11 -6 -1 4 9 14 GWElevation(ft,NAVD88)WellID:T0601300809-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601300810-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601300810-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601300810-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 GWElevation(ft,NAVD88)WellID:T0601300810-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601300810-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 GWElevation(ft,NAVD88)WellID:T0601300810-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601300810-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 37 42 47 52 57 62 67 72 77 82 87 GWElevation(ft,NAVD88)WellID:T0601306725-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 37 42 47 52 57 62 67 72 77 82 87 GWElevation(ft,NAVD88)WellID:T0601306725-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 35 40 45 50 55 60 65 70 75 80 85 GWElevation(ft,NAVD88)WellID:T0601306725-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 37 42 47 52 57 62 67 72 77 82 87 GWElevation(ft,NAVD88)WellID:T0601306725-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 36 41 46 51 56 61 66 71 76 81 86 GWElevation(ft,NAVD88)WellID:T0601306725-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -15 -5 5 15 25 35 45 55 65 75 85 GWElevation(ft,NAVD88)WellID:T0601306725-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 41 46 51 56 61 66 71 76 81 86 91 GWElevation(ft,NAVD88)WellID:T0601306725-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601325015-MPE-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601325015-MPE-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601325015-MPE-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601325015-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601325015-MW-1D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -13 -8 -3 2 7 12 17 22 27 32 37 GWElevation(ft,NAVD88)WellID:T0601325015-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -13 -8 -3 2 7 12 17 22 27 32 37 GWElevation(ft,NAVD88)WellID:T0601325015-MW-2D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601325015-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -19 -14 -9 -4 1 6 11 16 21 26 31 GWElevation(ft,NAVD88)WellID:T0601325015-MW-3D Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601325015-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601325015-MW-4R Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601325015-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -11 -6 -1 4 9 14 19 24 29 34 39 GWElevation(ft,NAVD88)WellID:T0601325015-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -12 -7 -2 3 8 13 18 23 28 33 38 GWElevation(ft,NAVD88)WellID:T0601325015-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -13 -8 -3 2 7 12 17 22 27 32 37 GWElevation(ft,NAVD88)WellID:T0601325015-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -18 -13 -8 -3 2 7 12 17 22 27 32 GWElevation(ft,NAVD88)WellID:T0601325015-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -23 -18 -13 -8 -3 2 7 12 17 22 27 GWElevation(ft,NAVD88)WellID:T0601330032-MW1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -22 -17 -12 -7 -2 3 8 13 18 23 28 GWElevation(ft,NAVD88)WellID:T0601330032-MW2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -24 -19 -14 -9 -4 1 6 11 16 21 26 GWElevation(ft,NAVD88)WellID:T0601330032-MW3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -24 -19 -14 -9 -4 1 6 11 16 21 26 GWElevation(ft,NAVD88)WellID:T0601330032-MW4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T0601341681-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -38 -33 -28 -23 -18 -13 -8 -3 2 7 12 GWElevation(ft,NAVD88)WellID:T0601341681-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -37 -32 -27 -22 -17 -12 -7 -2 3 8 13 GWElevation(ft,NAVD88)WellID:T0601341681-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 17 22 27 32 37 42 47 52 57 62 67 GWElevation(ft,NAVD88)WellID:T0601343310-EW1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 19 24 29 34 39 44 49 54 59 64 69 GWElevation(ft,NAVD88)WellID:T0601343310-EW2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601343310-EW3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601343310-MW1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601343310-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 17 22 27 32 37 42 47 52 57 62 67 GWElevation(ft,NAVD88)WellID:T0601343310-MW-11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 17 22 27 32 37 42 47 52 57 62 67 GWElevation(ft,NAVD88)WellID:T0601343310-MW-12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 15 20 25 30 35 40 45 50 55 60 65 GWElevation(ft,NAVD88)WellID:T0601343310-MW-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 15 20 25 30 35 40 45 50 55 60 65 GWElevation(ft,NAVD88)WellID:T0601343310-MW-14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 13 18 23 28 33 38 43 48 53 58 63 GWElevation(ft,NAVD88)WellID:T0601343310-MW-15 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 19 24 29 34 39 44 49 54 59 64 69 GWElevation(ft,NAVD88)WellID:T0601343310-MW2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601343310-MW3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 17 22 27 32 37 42 47 52 57 62 67 GWElevation(ft,NAVD88)WellID:T0601343310-MW4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 19 24 29 34 39 44 49 54 59 64 69 GWElevation(ft,NAVD88)WellID:T0601343310-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601343310-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 18 23 28 33 38 43 48 53 58 63 68 GWElevation(ft,NAVD88)WellID:T0601343310-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 17 22 27 32 37 42 47 52 57 62 67 GWElevation(ft,NAVD88)WellID:T0601343310-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 19 24 29 34 39 44 49 54 59 64 69 GWElevation(ft,NAVD88)WellID:T0601343310-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 20 25 30 35 40 45 50 55 60 65 70 GWElevation(ft,NAVD88)WellID:T0601359254-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 21 26 31 36 41 46 51 56 61 66 71 GWElevation(ft,NAVD88)WellID:T0601359254-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 21 26 31 36 41 46 51 56 61 66 71 GWElevation(ft,NAVD88)WellID:T0601359254-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 2 7 12 17 22 27 32 37 42 47 52 GWElevation(ft,NAVD88)WellID:T0601359797-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -5 0 5 10 15 20 25 30 35 40 45 GWElevation(ft,NAVD88)WellID:T0601359797-MW-13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -1 4 9 14 19 24 29 34 39 44 49 GWElevation(ft,NAVD88)WellID:T0601359797-MW-15 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -3 2 7 12 17 22 27 32 37 42 47 GWElevation(ft,NAVD88)WellID:T0601359797-MW-16 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 4 9 14 19 24 29 34 39 44 49 54 GWElevation(ft,NAVD88)WellID:T0601359797-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 1 6 11 16 21 26 31 36 41 46 51 GWElevation(ft,NAVD88)WellID:T0601359797-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 0 5 10 15 20 25 30 35 40 45 50 GWElevation(ft,NAVD88)WellID:T0601359797-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 10 20 30 40 50 60 70 80 90 100 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -48 -38 -28 -18 -8 2 12 22 32 42 52 GWElevation(ft,NAVD88)WellID:T0601359797-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 3 8 13 18 23 28 33 38 43 48 53 GWElevation(ft,NAVD88)WellID:T0601359797-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 2 7 12 17 22 27 32 37 42 47 52 GWElevation(ft,NAVD88)WellID:T0601359797-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -44 -39 -34 -29 -24 -19 -14 -9 -4 1 6 GW Elevation (ft, NAVD88) WellID:T0601376629-MW1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -45 -40 -35 -30 -25 -20 -15 -10 -5 0 5 GW Elevation (ft, NAVD88) WellID:T0601376629-MW2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -45 -40 -35 -30 -25 -20 -15 -10 -5 0 5 GW Elevation (ft, NAVD88) WellID:T0601376629-MW3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -46 -41 -36 -31 -26 -21 -16 -11 -6 -1 4 GW Elevation (ft, NAVD88) WellID:T0601376629-MW4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 GW Elevation (ft, NAVD88) WellID:T0601378938-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -56 -51 -46 -41 -36 -31 -26 -21 -16 -11 -6 GW Elevation (ft, NAVD88) WellID:T0601378938-MW-10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 GW Elevation (ft, NAVD88) WellID:T0601378938-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -56 -51 -46 -41 -36 -31 -26 -21 -16 -11 -6 GW Elevation (ft, NAVD88) WellID:T0601378938-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 GW Elevation (ft, NAVD88) WellID:T0601378938-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 GW Elevation (ft, NAVD88) WellID:T0601378938-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -56 -51 -46 -41 -36 -31 -26 -21 -16 -11 -6 GW Elevation (ft, NAVD88) WellID:T0601378938-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 GW Elevation (ft, NAVD88) WellID:T0601378938-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 -5 GW Elevation (ft, NAVD88) WellID:T0601378938-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -56 -51 -46 -41 -36 -31 -26 -21 -16 -11 -6 GW Elevation (ft, NAVD88) WellID:T0601378938-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601389036-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601389036-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T0601389036-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601391419-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -41 -36 -31 -26 -21 -16 -11 -6 -1 4 9 GW Elevation (ft, NAVD88) WellID:T0601391419-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 GWElevation(ft,NAVD88)WellID:T0601391419-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -20 -15 -10 -5 0 5 10 15 20 25 30 GWElevation(ft,NAVD88)WellID:T0601391420-EX-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-EX-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-MW-1-I Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -20 -15 -10 -5 0 5 10 15 20 25 30 GWElevation(ft,NAVD88)WellID:T0601391420-MW-2-I Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-MW-3-I Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -20 -15 -10 -5 0 5 10 15 20 25 30 GWElevation(ft,NAVD88)WellID:T0601391420-MW-4-I Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -20 -15 -10 -5 0 5 10 15 20 25 30 GWElevation(ft,NAVD88)WellID:T0601391420-MW-5-I Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -21 -16 -11 -6 -1 4 9 14 19 24 29 GWElevation(ft,NAVD88)WellID:T0601391420-MW-8 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -20 -15 -10 -5 0 5 10 15 20 25 30 GWElevation(ft,NAVD88)WellID:T0601391420-MW-9 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.01 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T10000000655-MW.02 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -34 -29 -24 -19 -14 -9 -4 1 6 11 16 GWElevation(ft,NAVD88)WellID:T10000000655-MW.03 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.04 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.05 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.06 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.07 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.08 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.09 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.10 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.11 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.12 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.13 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -35 -30 -25 -20 -15 -10 -5 0 5 10 15 GWElevation(ft,NAVD88)WellID:T10000000655-MW.14 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 74 79 84 89 94 99 104 109 114 119 124 GWElevation (ft, NAVD88) WellID:T10000002015-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 76 81 86 91 96 101 106 111 116 121 126 GWElevation(ft,NAVD88)WellID:T10000002015-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 74 79 84 89 94 99 104 109 114 119 124 GW Elevation (ft, NAVD88) WellID:T10000002015-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 75 80 85 90 95 100 105 110 115 120 125 GWElevation(ft,NAVD88)WellID:T10000002015-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) 75 80 85 90 95 100 105 110 115 120 125 GWElevation (ft, NAVD88) WellID:T10000002015-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -57 -52 -47 -42 -37 -32 -27 -22 -17 -12 -7 GW Elevation (ft, NAVD88) WellID:T10000003258-MW-1 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -57 -52 -47 -42 -37 -32 -27 -22 -17 -12 -7 GW Elevation (ft, NAVD88) WellID:T10000003258-MW-2 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -62 -57 -52 -47 -42 -37 -32 -27 -22 -17 -12 GWElevation(ft,NAVD88)WellID:T10000003258-MW-3 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -62 -57 -52 -47 -42 -37 -32 -27 -22 -17 -12 GWElevation(ft,NAVD88)WellID:T10000003258-MW-4 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -59 -54 -49 -44 -39 -34 -29 -24 -19 -14 -9 GW Elevation (ft, NAVD88) WellID:T10000003258-MW-5 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -60 -55 -50 -45 -40 -35 -30 -25 -20 -15 -10 GWElevation(ft,NAVD88)WellID:T10000003258-MW-6 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): 0 5 10 15 20 25 30 35 40 45 50 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020Depth to Water (ft) -57 -52 -47 -42 -37 -32 -27 -22 -17 -12 -7 GW Elevation (ft, NAVD88) WellID:T10000003258-MW-7 Source:Geotracker Zone:Shallow Well Depth (ft):N/AN/APerf Int (ft): {R_WLhyd88} Historical Groundwater Elevation Contour Maps APPENDIX 3e in 'o'-Y� � : _.. � � s .. �- ., 4 I� rr=3il LLJHDDRFF & SCALMANINI l:IC□NSULTING ENGINEERS --"�{ 'Q?' � I RA KS TRACT [STATE RECREA'l10N AREA) -1 �-'--=:���i\) • \o,� l St•- � " . • Mc De �sis ✓ ). � � LEGEND -30_..,.,.--Contours of Equal Water Surface .,,,-Elevation (feet, mean sea level). Scale in Feet 0' 4500' 9000' 18000' Contours of Equal Ground-Water Elevation - Spring 1958 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California in 'o'-Y� � : _.. � � s .. �- ., 4 I� rr::I LUHDORFF &. SCALMANINI l:.IC□NSULTING ENGINEERS --"�{ 'Q?' � I RA KS TRACT [STATE RECREA'l10N AREA) -1 �-'--=:���i\) • \o,� l St•- � " . • Mc De �sis ✓ ). � � LEGEND -30_..,.,.--Contours of Equal Water Surface .,,,-Elevation (feet, mean sea level). Scale in Feet 0' 4500' 9000' 18000' Contours of Equal Ground-Water Elevation - Fall 1958 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ;;,, '()\"Y� � .-._ .. � . � s .. �- ., 4 I� rr::I LUHDDRFF &. SCALMANINI l:.IC □NSULTING ENGINEERS --"�{ 'Q?' � I RA KS TRACT [STATE RECREA'l10N AREA) -1 �-'--=:���i\) • \o,� l St•- � " . • Mc De �sis ✓ ). � � LEGEND -30_..,.,.--Contours of Equal Water Surface ,,,-Elevation (feet, mean sea level). Scale in Feet O' 4500' 9000' 18000' Contours of Equal Ground-Water Elevation - Spring 1975 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ;;,, '()\"Y� � .-._ .. � . � s .. �- ., 4 I� lr::I LLJHDDRFF & SCALMANINI l:IC □NSULTING ENGINEERS --"�{ 'Q?' � I RA KS TRACT [STATE RECREA'l10N AREA) -1 �-'--=:���i\) • \o,� l St•- � " . • Mc De �sis ✓ ). � � LEGEND -30_..,.,.--Contours of Equal Water Surface ,,,-Elevation (feet, mean sea level). Scale in Feet O' 4500' 9000' 18000' Contours of Equal Ground-Water Elevation - Fall 1975 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ;;,, '()\"Y� � .-._ .. � . � s .. �- ., 4 I� lr::I LUHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.IJ;.o� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND _ 30 _/ Contours of Equal Water Surface ,,,-Elevation (feet, mean sea level). Scale in Feet O' 4500' 9000' 18000' Contours of Equal Ground-Water Elevation - Spring 1977 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ��,., '0'� . 15• ., 4 �f I 11'::31 LUHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS , ----,, -==----1 -J��-'�·� � �� I? g Br ak --� / = 2)ri,(' �o,'-0 o..., t - -. =-,. RA KS TRACl [STATE RECREATION AREAi -���� -=::;;;:;;::;:;:,,,,-_\ ,. G Qng St• • ( ' Isla ). j d u I LEGEND _,,,----30_/ Contours of Equal Water Surface Elevation (feet, mean sea level). Scale in Feet 0' 4500' 9000' 18000' Contours of Equal Ground-Water Elevation - Fall 1986 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ;;,, '()\"Y� � .-._ .. � . � s .. �- ., 4 I� rr=3I LLJHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.IJ;.o� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND _ 30 _/ Contours of Equal Water Surface ,,,-Elevation (feet, mean sea level). Scale in Feet O' 4500' 9000' 18000' Contours of Equal Ground-Water Elevation - Spring 1991 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ;;,, '()\"Y� � .-._ .. � . � s .. �- ., 4 I� rr=3I LLJHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.IJ;.o� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND _ 30 _/ Contours of Equal Water Surface ,,,-Elevation (feet, mean sea level). Scale in Feet O' 4500' 9000' 18000' Contours of Equal Ground-Water Elevation - Fall 1991 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ;;,, '()\"Y� � .-._ .. � . � s .. �- ., 4 I� rr=3I LLJHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.IJ;.o� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND _ 30 _/ Contours of Equal Water Surface ,,,-Elevation (feet, mean sea level). Scale in Feet O' 4500' 9000' 18000' Contours of Equal Ground-Water Elevation - Fall 1996 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California in 'o'-Y� � : _.. � � s .. �- ., 4 I� rr=3I LLJHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.ll;-0� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND � 10_/ Contours of Depth to Water (feet). Scale in Feet 0' 4500' 9000' 18000' Contours of Depth to Water - Spring 1958 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California in 'o'-Y� � : _.. � � s .. �- ., 4 I� rr=3I LLJHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.ll;-0� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND � 10_/ Contours of Depth to Water (feet). Scale in Feet 0' 4500' 9000' 18000' Contours of Depth to Water - Fall 1958 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ;;,, '()\"Y� � .-._ .. � . � s .. �- ., 4 I� rr::I LUHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.IJ;.o� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND � 10_/ Contours of Depth to Water (feet). Scale in Feet O' 4500' 9000' 18000' Contours of Depth to Water - Spring 1975 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ;;,, '()\"Y� � .-._ .. � . � s .. �- ., 4 I� rr=3il LLJHDDRFF & SCALMANINI l:IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.IJ;.o� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND � 10_/ Contours of Depth to Water (feet). Scale in Feet O' 4500' 9000' 18000' Contours of Depth to Water - Fall 1975 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California in 'o'-Y� � : _.. � � s .. �- ., 4 I� lr::I LUHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.ll;-0� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND � 10_/ Contours of Depth to Water (feet). Scale in Feet 0' 4500' 9000' 18000' Contours of Depth to Water - Spring 1977 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California in 'o'-Y� � : _.. � � s .. �- ., 4 I� 11'::1 LUHDORFF & SCALMANINI l:iJc□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.ll;-0� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND � 10_/ Contours of Depth to Water (feet). Scale in Feet 0' 4500' 9000' 18000' Contours of Depth to Water - Fall 1986 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ;;,, '()\"Y� � .-._ .. � . � s .. �- ., 4 I� lr::I LUHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.IJ;.o� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND � 10_/ Contours of Depth to Water (feet). Scale in Feet O' 4500' 9000' 18000' Contours of Depth to Water - Spring 1991 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California in 'o'-Y� � : _.. � � s .. �- ., 4 I� lr::I LUHDDRFF & SCALMANINI l:.IC□NSULTING ENGINEERS .,,, Ind,:£� oinr [ rr:-= -3e1 ';> -// ----ti ' -;,.ll;-0� \. ��t q Br ·ak --"�{ 'Q?' � I RA KS TRACT [STATE RECREATION AREA) -1 �-'--=:���i\) • \o,� l St•- , " . • Mc De �sis ✓ ). � � LEGEND � 10_/ Contours of Depth to Water (feet). Scale in Feet 0' 4500' 9000' 18000' Contours of Depth to Water - Fall 1991 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California ��,., '0'� . 15• ., 4 �f I 11'::31 LUHDORFF & SCALMANINI l:.IC□NSULTING ENGINEERS ---- -==----1 -J��-'�·� � �� I? g Br ak --� / = o,>.O , . /J11.• "' � o..., tE /· RA KS TRACl [STATE RECREATION AREAi ,. G Qng St• • ' Isla d u I LEGEND ,,,.----1 o_/ Contours of Depth to Water {feet). Scale in Feet 0' 4500' 9000' 18000' Contours of Depth to Water - Fall 1996 East Contra Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California Groundwater Quality Table APPENDIX 3f Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow Aquifer City of Brentwood -<2 <20-12/17/2008 -1180 --139 70 103 5 116 370 --27.6 2 120-70200 -BG-1 <0.01 -<2 <20-2/17/2009 -1410 --178 95 116 4 107 500 --27.8 2 60-90200 -BG-1 <0.01 -<2 <20-5/12/2009 -1720 --187 100 111 3 108 580 --31.4 2 80-40200 -BG-1 <0.01 -<2 <20-8/4/2009 -1580 --185 93 125 3 114 490 --33.4 3 140-60300 -BG-1 <0.01 -<2 <20-11/10/2009 -1670 --178 98 116 2 111 520 --32.3 3 <50-<10200 -BG-1 <0.01 -<2 <20-2/25/2010 -1480 --177 100 123 3 119 520 --31.2 2 80-<10200 -BG-1 <0.01 -<2 <20-5/26/2010 -1640 --199 104 128 2 121 610 --32.5 3 80-10200 -BG-1 <0.01 -<2 20-8/12/2010 -1740 --184 101 124 2 132 610 --29.1 3 70-<10200 -BG-1 <0.01 --<0.84-11/15/2010 3864 1520 --157 81 114 2 -403 190160 31.4 3 <50-<10--BG-1 <0.001 --<20-2/24/2011 2251 1280 --155 84 105 2 -500 190150 32.8 3 <50-<10--BG-1 <0.001 --<20-5/15/2011 2070 1420 --151 81 108 2 -470 190150 -3 <50-<10--BG-1 <0.001 ----8/23/2011 1927 1250 ----108 --358 --32 ----200 -BG-1 - -<2 <20-12/20/2011 1628 970 --119 66 94 2 -316 190160 31 4 <50-<10--BG-1 <0.001 ----2/27/2012 1716 1080 ----105 --305 --32 ------BG-1 - -2.31 <20-5/23/2012 1675 1020 --121 64.6 153 1.52 -294 199163 29 3.65 <50-<10--BG-1 <0.001 ----8/13/2012 1598 1010 --- -99 --233 --28 ----200 -BG-1 - -3 <20-11/13/2012 1545 920 --114 61 94 2 -239 190160 29 6 <50-<10--BG-1 <0.001 ----2/18/2013 1506 897 --- -96.7 --242 --27.1 ------BG-1 - --<20-5/15/2013 1490 944 --111 58.3 93.4 1.48 -235 208170 27.1 3.44 <50-<10--BG-1 <0.001 ----8/15/2013 1479 925 --- -87.7 --266 --28.7 ------BG-1 - --<20-11/11/2013 1370 888 --104 54.8 88.2 1.17 -193 188154 26.2 -<50-<10--BG-1 - ----2/17/2014 1358 830 --- -87.7 --195 --29.4 ------BG-1 - --<20-5/15/2014 1367 914 --92.7 50 79 <1 -201 176145 21 4.08 104-<10--BG-1 <0.001 ----8/14/2014 -913 --- -86 --197 --25.1 ------BG-1 - --<20-11/11/2014 1317 842 --92.7 48 79.8 1.22 -190 172141 27.1 4.56 99.4-<10--BG-1 <0.001 ----2/16/2015 -908 --- -82.2 --259 --27.4 ----237 -BG-1 - 0.122 3.38 1.35-6/8/2015 -749 --86.2 43.5 76 1.18 97.1 169 161-26 3.48 ND-5.17220 -BG-1 <0.001 ----8/17/2015 -919 --- -79.7 --171 --26.9 ----253 -BG-1 - 0.137 1.95 8.75-12/7/2017 -896 --81.6 43.3 66.9 1.08 125 194 170-31 3.79 134-18.2227 -BG-1 0.00153 ----2/17/2008 -1520 --- - - --- ---------BG-2 - -2 <20-12/17/2008 -1550 --185 88 198 8 390 290 --28.7 3 140-2501800 -BG-2 <0.01 -4 <20-2/17/2009 -1520 --192 91 197 7 380 280 --28.7 2 60-1301900 -BG-2 <0.01 -3 <20-5/12/2009 -1520 --180 86 185 6 380 270 --30.5 2 90-601800 -BG-2 <0.01 -3 <20-8/4/2009 -1450 --191 85 206 7 400 270 --25.5 2 160-701900 -BG-2 <0.01 -3 <20-11/10/2009 -1440 --172 84 185 6 370 280 --19.8 3 <50-501900 -BG-2 <0.01 -3 <20-2/25/2010 -1450 --177 87 183 6 350 270 --16.9 <0.001 60-401900 -BG-2 <0.01 -2 20-5/26/2010 -1520 --184 87 178 6 390 280 --16.7 1 50-401800 -BG-2 <0.01 Thursday, September 10, 2020Page 1 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow Aquifer City of Brentwood -2 <20-8/12/2010 -1550 --188 89 175 6 440 310 --15.4 3 70-401800 -BG-2 <0.01 --<0.84-11/15/2010 4500 ---204 95 183 6 -277 460380 -3 60-40--BG-2 <0.001 --<20-2/24/2011 2414 ---186 87 156 5 -280 450370 -2 60-30--BG-2 <0.001 --<20-5/15/2011 2350 ---214 96 178 6 -300 470390 -2 80-40--BG-2 <0.001 ----8/23/2011 2419 1600 ----187 --260 --14.7 ----1800 -BG-2 - -2 <20-12/20/2011 2232 1570 --189 88 163 6 -280 500410 15.9 2 <50-30--BG-2 0.001 ----2/27/2012 2431 1620 ----194 --280 --17.9 ------BG-2 - -2.69 <20-5/23/2012 2418 1620 --209 92.9 193 5.92 -290 485397 17.6 2.59 <50-24.5--BG-2 <0.001 ----8/13/2012 2441 1600 ----192 -----16 ----1800 -BG-2 - -6 <20-11/13/2012 2342 1580 --208 93 188 6 -270 490400 66.7 7 <50-301800 -BG-2 0.003 ----2/18/2013 2349 1580 ----195 --284 --63 ----1840 -BG-2 - -2.17 <20-5/15/2013 2344 1590 --205 90.5 184 5.49 -278 539442 55.3 2.56 <50-23.31820 -BG-2 0.00102 ----8/15/2013 2305 1570 ----173 --308 --13.8 ----1870 -BG-2 - --<20-11/11/2013 2290 1610 --223 99.8 11 6.08 -244 529433 11.1 -<50-25.42030 -BG-2 - ----2/17/2014 2328 1540 --- -188 --266 --10 ----2070 -BG-2 - -2.26 <20-5/15/2014 2275 1540 --184 83.6 172 5.29 -260 506415 11.2 4.2 102-211930 -BG-2 <0.001 ----8/14/2014 -1540 --- -172 --255 --40.5 ----1940 -BG-2 - -2.32 <20-11/11/2014 2323 1580 --200 87.9 171 5.38 -270 536440 36.9 3.04 162-21.41940 -BG-2 0.0341 ----2/15/2015 -1610 --- -174 --278 --33.1 ----2040 -BG-2 - ----2/16/2015 -1610 --- - - --- ---------BG-2 - 0.096 4.41 2.2-6/8/2015 -1620 --193 87.6 184 6.39 28.3 250 561-6.4 3.45 ND-3.912030 -BG-2 <0.001 ----8/17/2015 -1610 --- -192 --258 --6.4 ----2020 -BG-2 - 0.115 2.62 4.83-12/7/2017 -1580 --165 72.7 176 4.59 404 292 585-5.2 5.18 38.1-7.21800 -BG-2 0.0023 ----2/17/2008 -740 --- - - --- ---------BG-3 - -4 <20-12/17/2008 -710 --76 35 147 16 109 152 --14.1 32 120-<10900 -BG-3 <0.01 -5 <20-2/17/2009 -740 --72 35 148 14 110 140 --14.8 11 <50-10800 -BG-3 <0.01 -3 <20-5/12/2009 -780 --90 49 135 5 135 148 --16.6 3 100-50900 -BG-3 <0.01 -3 <20-8/4/2009 -760 --78 40 136 6 120 137 --14.6 8 50-<10900 -BG-3 <0.01 -4 <20-11/10/2009 -770 --76 40 132 5 117 139 --14.1 6 50-10900 -BG-3 <0.01 -4 <20-2/25/2010 -750 --78 41 135 5 116 137 --13.2 5 <50-10900 -BG-3 <0.01 -4 <20-5/26/2010 -770 --84 43 124 3 119 142 --13.4 3 <50-10900 -BG-3 <0.01 -<2 <0.84-11/16/2010 1300 790 --87 40 139 5 -144 350290 11.1 6 <50-101000 -BG-3 <0.001 -3 <20-2/24/2011 1373 810 --80 41 119 3 -159 360300 10.9 5 80-361000 -BG-3 <0.001 -3 <20-5/15/2011 1360 810 --90 44 130 5 -158 360300 <0.1 6 100-<101000 -BG-3 <0.001 ----8/23/2011 1365 760 --- -141 --156 --8.6 ----1100 -BG-3 - -3 <20-12/20/2011 1279 750 --79 41 124 4 -164 380310 7.8 7 <50-<101000 -BG-3 <0.001 ----2/27/2012 1416 820 --- -140 --170 --7.2 ----1100 -BG-3 - Thursday, September 10, 2020Page 2 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow Aquifer City of Brentwood -3.6 <20-5/23/2012 1408 811 --88 43.6 142 <0.1 -177 388318 7.1 8.85 <50-<101060 -BG-3 <0.001 ----8/13/2012 1384 780 ----153 --159 --5.4 ----1000 -BG-3 - -4 <20-11/13/2012 1315 800 --92 45 147 4 -173 420340 24.6 12 80-<101100 -BG-3 0.001 ----2/18/2013 1336 819 ----150 --189 --21.9 ----1100 -BG-3 - -2.68 <20-5/15/2013 1303 831 --88 43.6 150 4.44 -201 384315 <0.1 5.6 <50-131120 -BG-3 <0.001 ----8/15/2013 1366 828 ----149 --226 --8.5 ----1110 -BG-3 - --<20-11/11/2013 1400 860 --94.1 47.3 143 2.89 -188 373305 7.1 -<50-113001150 -BG-3 - ----2/17/2014 1387 825 ----150 --203 --6.89 ----1250 -BG-3 - -2.63 <20-5/15/2014 1385 865 --83.1 41.2 137 4.07 -201 352288 7.74 8.14 ND-<101100 -BG-3 <0.001 ----8/14/2014 -818 ----138 --185 --37 ----1080 -BG-3 - -2.68 <20-11/11/2014 1399 770 --81.2 40.2 133 4.1 -206 330271 6.7 7.58 82-ND1080 -BG-3 0.00152 ----2/15/2015 -844 ----138 --227 --24 ----1130 -BG-3 - 0.098 4.49 0.873-6/8/2015 -858 --86.6 41.5 138 4.46 98.3 215 332-4.9 7.7 ND-2.91020 -BG-3 0.00133 ----8/17/2015 -893 ----144 --214 --5.1 ----1100 -BG-3 - 0.106 2.90 3.77-12/7/2017 -978 --94.5 46.2 141 4.28 113 267 408-8.4 9.59 17.1-5.191130 -BG-3 0.0017 0.31 10 50-8/16/1990 2045 1166 -18413268.2 140 5.1 155 337 306306 11.4 16 100113 10-5WELL 01 - Town of Discovery Bay 0.44 ---3/19/2013 2000 1100 7.56 -61 59 290 2 61 360 470470 <0.45 -<100-570--1BMW-140 - 0.11 ---3/20/2013 6800 5000 7.21 -460 320 480 2.5 320 2000 300300 <0.45 ------4AMW-152 - 0.59 ---3/20/2013 6500 5400 7.34 -400 260 630 3.9 310 1900 280280 <0.45 ------7MW-115 - BALDOCCHI WATER SYSTEM 0.6 <2 50-10/22/2002 1400 840 -<5075 38 160 1.2 110 190 380320 7.2 <10 100<100 <20-<5Well Head - ----7/7/2004 ----- - - --- --8.8 ------Well Head - ----7/6/2005 ----- - - --- --12 ------Well Head - ----7/11/2007 ----- - - --- --13 ------Well Head - ----7/3/2008 ----- - - --- --14 ------Well Head - ----7/2/2009 ----- - - --- --13 ------Well Head - ----7/1/2010 ----- - - --- --14 ------Well Head - ----7/7/2011 ----- - - --- --14 ------Well Head - ----6/4/2012 ----- - - --- --16 ------Well Head - ----6/19/2012 ----- - - --- --8.6 ------Well Head - ----7/8/2013 ----- - - --- --11 ------Well Head - ----7/8/2014 ----- - - --- --7.5 ------Well Head - ----7/16/2015 ----- - - --- --3.2 ------Well Head - Thursday, September 10, 2020Page 3 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow Aquifer BALDOCCHI WATER SYSTEM ----7/19/2016 ------------7.1 ------Well Head - ----7/12/2017 ------------17 ------Well Head - ----7/16/2018 ------------16 ------Well Head - ----7/2/2019 ------------16 ------Well Head - ----12/10/2019 ------------8.1 ------Well Head - Byron-Bethany Irrigation District ----8/9/1973 3090 1720 8 -52 22 558 5.5 160 697 -272 9.4 ----6500 -5 Binn - ----6/24/1975 3050 -8.1 ---600 --778 -253 -------5 Binn - ----7/20/1977 4200 -7.9 ---780 --1210 -224 -------5 Binn - ----8/3/1979 1860 -8.5 -27 10 358 --358 -274 -------5 Binn - ----11/3/1980 2120 -8.4 -28 11 ---462 -239 -----4200 -5 Binn - ----5/26/1981 1660 -8.4 -21 8 ---308 -263 -----3400 -5 Binn - ----8/3/1981 2550 -8 -42 15 472 --575 -249 -------5 Binn - ----6/8/1982 1980 1160 8.2 -30 12 379 3 106 419 -260 -----4100 -5 Binn - ----8/16/1983 1830 1060 8.1 -26 11 339 2.8 102 363 -258 -----3800 -5 Binn - ----8/1/1985 1970 -8.6 -30 12 370 --395 -258 -------5 Binn - ----7/28/1987 1450 -8.2 -21 10 275 --234 -261 -------5 Binn - ----9/14/1989 1620 -8.4 -21 9 316 1.4 -286 -262 -------5 Binn - Deep Aquifer City of Brentwood 0.3 ---4/26/1999 -740 --73 34 140 4 230 87 -230 2.07828 ---1001300 -MW-14 Deep - 0.4 ---4/26/1999 -460 --64 24 62 2 56 77 -220 2.14605 ---150500 -MW-14 Int.- 0.35 10 50-8/16/1990 1080 --10057.6 33.3 108 3.2 192 94.6 223223 3.05 13 100100 10-5Well 06 - 0.3 10 50-4/30/1991 960 640 -10073 33 95 3 99 126 274225 2.9 10 100100 30-5Well 06 - 0.2 5 50-1/7/1993 1200 793 -8593 39 3 110 204 133 265217 2 14 5020 30-5Well 06 - ----5/2/1994 ----- - - --- --3.2 ------Well 06 - ----4/4/1995 ----- - - --- ---------Well 06 - 0.3 <2 <50-6/30/1999 1450 930 -<5094 45 156 3 269 184 280230 3.3 10 <10044.5 <201200 9Well 06 - 0.2 <2 <50-12/26/2000 1510 --<5090 45 157 4 269 180 260210 3.43 9 <10040.1 <201200 6Well 06 - ----5/2/2001 ----- - - --- --3.64 ------Well 06 - 0.4 <2 <50-8/1/2001 1510 990 -<5084 42 163 4 277 174 260220 3.25 10 <10042.7 <201190 8Well 06 - ----2/27/2002 ----- - - --- --4 ------Well 06 - 0.3 2 20-9/11/2002 1530 1000 -1094 45 148 4 246 181 270220 3.19 10 5044.6 101210 8Well 06 - 0.2 2 20-4/17/2003 1560 970 -1093 44 171 4 291 205 260220 -9 5044.6 101180 9Well 06 - Thursday, September 10, 2020Page 4 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood -2 --11/19/2003 -------------------Well 06 - 0.7 2 20-6/2/2004 1600 1000 -1095441734275215260210-8 5049.5 101100 8Well 06 - 0.4 2 20-3/30/2005 1500 --10954516442531682702203.52 10 5042 101300 9Well 06 - 0.4 2 20-3/29/2006 1590 1010 -10944416032942062602104.13 7 5040.3 101200 8Well 06 - 0.4 2 20-3/20/2007 1490 920 -10793621832601792602204.13 9 5039 101300 9Well 06 - 0.2 2 20-3/12/2008 1520 --10884215032401742502103.91 10 6042.3 101200 10Well 06 - ----4/9/2008 ------------4.3 ------Well 06 - ----8/27/2008 ------------3.8 ------Well 06 - 0.34 2 50-2/18/2009 1600 810 -50100491703.7 280 210 260220 4.5 11 100100 20-11Well 06 - 0.34 2 50-7/14/2010 1700 1100 -50110531803.7 300 230 260210 -10 100100 201300 8.6Well 06 - 0.31 2.5 50-2/16/2011 1700 1100 -50110521803.8 290 220 260210 5 10 100100 201300 12Well 06 - 0.36 2 50-5/16/2012 1600 980 -5092461703.7 280 230 250200 4.1 10 100100 20-5Well 06 - 0.32 2 50-5/29/2013 1700 --501105319043002302502105.2 10 100100 20-11Well 06 - 0.34 2.4 50-6/19/2014 1700 1100 -50100501703.8 290 220 230190 5.2 10 100100 201300 11Well 06 - 0.35 2 50-4/14/2015 1600 1100 -50100 51 180 3.9 300 230 260220 5.2 10 100100 201300 14Well 06 - ----5/13/2015 ----- - - --- --5.33 ------Well 06 - ----8/26/2015 ----- - - --- --5.6 ------Well 06 - ----11/18/2015 ----- - - --- --2.2 ------Well 06 - ----3/31/2016 ----- - - --- --5.5 ------Well 06 - 0.33 2 50-5/31/2016 1600 1000 -50110 52 180 4.1 300 220 260210 5.7 10 100100 201400 11Well 06 - ----9/14/2016 ----- - - --- --5.4 ------Well 06 - ----12/7/2016 ----- - - --- --5.6 ------Well 06 - ----1/25/2017 ----- - - --- --2.9 ------Well 06 - ----5/10/2017 ----- - - --- --5.8 ------Well 06 - ----8/16/2017 ----- - - --- --6.1 ------Well 06 - 0.35 2.6 50-8/24/2017 1700 --50110 51 180 4.1 290 220 270220 5.7 10 100100 201300 12Well 06 - ----12/12/2017 ----- - - --237 ---------Well 06 - ----12/13/2017 ----- - - --- --6.4 ------Well 06 - ----2/21/2018 ----- - - --- --5.3 ------Well 06 - 0.34 2 50-5/7/2018 1600 1000 -5099 46 170 4 290 210 250210 5.5 10 100100 201200 11Well 06 - ----9/26/2018 ----- - - --- --4.9 ------Well 06 - ----11/7/2018 ----- - - --- --4.6 ------Well 06 - ----3/11/2019 ----- - - --- --5.6 ------Well 06 - 0.31 <2 <50-5/6/2019 -1100 -<50-51 180 4.4 320 240 --6.3 <10 <100-<201300 10Well 06 - ----6/19/2019 ----- - - --- --5.9 ------Well 06 - ----8/7/2019 ----- - - --- --5.7 ------Well 06 - 0.2 4 20-5/5/1988 986 660 --62 33 110 3.2 150 64 230230 2.7 10 5031 10-3.2Well 07 - Thursday, September 10, 2020Page 5 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood 0.3 10 50-8/16/1990 947 608 -10049.7 30.2 102 3.7 166 75.1 224224 2.1 10 287100 18-5Well 07 - 0.3 10 50-4/30/1991 940 --10060291003112992512061.8 10 100100 30-5Well 07 - 0.2 5 50-1/7/1993 1000 --21775323110146992682200.5 10 5020 30-5Well 07 - ----5/2/1994 ------------1.6 ------Well 07 - ----4/4/1995 -------------------Well 07 - 0.3 <2 <50-6/30/1999 1140 --<5072321242208992702201.4 9 11032.7 <201400 7Well 07 - 0.2 <2 <50-12/20/2000 1200 740 -<50663213332381022602101.6 7 <10031.8 <201400 6Well 07 - ----5/2/2001 ------------1.7 ------Well 07 - 0.3 <2 <50-8/1/2001 1210 --<50653114032341062702201.6 9 <10035.3 <201340 8Well 07 - ----2/27/2002 ------------1.7 ------Well 07 - 0.2 2 20-9/11/2002 1160 760 -10683212031841052702201.4 9 7034.6 101340 7Well 07 - 0.2 2 20-4/17/2003 1190 760 -10693113732151102702201.9 8 5035.1 101380 8Well 07 - -2 --3/18/2004 -------------------Well 07 - 0.3 2 20-3/29/2004 1270 760 -10823713832181312702202.33 7 5036.3 101400 7Well 07 - -2 --4/14/2004 ----- - - --- ---------Well 07 - -2 --5/12/2004 ----- - - --- ---------Well 07 - 0.4 2 20-3/30/2005 1370 880 -1080 36 161 3 222 155 260220 1.2 7 5039.9 101500 8Well 07 - 0.3 2 20-3/29/2006 1270 830 -1070 31 141 3 216 137 240210 1.7 5 5032.6 101400 6Well 07 - 0.4 2 20-10/10/2007 1380 880 -1074 33 182 3 240 171 260210 2.1 6 5038.8 101500 9Well 07 - 0.5 2 20-2/25/2008 1490 810 -1075 34 167 3 210 197 240200 2 6 5041.8 101400 10Well 07 - 0.35 2 50-2/18/2009 1300 730 -5075 35 160 3 230 150 260210 -10 100100 20-9.2Well 07 - 0.33 2 50-2/10/2010 1300 840 -5076 35 160 3 220 160 250210 2.5 10 100100 201500 7.1Well 07 - 0.29 2.7 50-2/16/2011 1500 890 -5079 37 170 3.1 130 110 250200 5.8 10 100100 201500 11Well 07 - 0.38 2.5 50-6/27/2012 1700 1100 -5082 39 220 3.2 250 290 220180 1.2 10 100100 20-9.7Well 07 - 0.31 2 50-5/29/2013 1400 900 -5078 36 180 3.2 230 180 210180 2.9 10 100100 20-11Well 07 - 0.33 2 50-6/17/2014 1400 860 -5073 34 180 3.4 220 200 210180 2.7 10 100100 201400 10Well 07 - 0.33 2 50-4/14/2015 1400 900 -5076 35 160 2.9 240 190 250200 2.9 10 100100 201400 14Well 07 - 0.32 2 50-5/31/2016 1300 --5078 36 170 3.3 220 170 240200 3.2 10 100100 201600 9Well 07 - 0.34 2.4 50-8/24/2017 1400 890 -5080 37 160 3 220 180 250210 3.4 10 100100 201500 9.5Well 07 - 0.32 2 50-5/7/2018 1400 --5077 34 160 3.3 220 180 250200 3.4 10 100100 201400 9.6Well 07 - 0.3 <2 <50-5/6/2019 -920 -<5084 38 180 3.8 240 230 --3.3 <10 <100-<201500 10Well 07 - 0.32 <2 20-6/14/1993 1000 510 -<5086 13 100 -140 70 -230 4.1 <10 130<100 <20-6Well 08 - ----2/15/1994 ----- - - --- --1.8 ------Well 08 - 0.34 <2 <50-12/20/1994 1024 --25063 32 90 3 168 80 221221 <1.02 <10 223<100 <20-<5Well 08 - 0.3 <2 <50-7/7/1999 1340 840 -<5090 41 137 4 228 146 290240 1.2 8 <10046.8 <201300 8Well 08 - 0.3 <2 <50-8/1/2001 1400 --<5087 39 149 4 260 156 270220 1.1 7 <10048.3 <201360 7Well 08 - ----3/6/2002 ----- - - --- --1.2 ------Well 08 - Thursday, September 10, 2020Page 6 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood 0.2 2 20-8/21/2002 1350 890 -10813814532171532702201 7 5043.7 101320 7Well 08 - -2 --11/19/2003 -------------------Well 08 - -2 --3/18/2004 -------------------Well 08 - 0.3 2 20-3/29/2004 1330 840 -1084381483216158270220-6 5038.6 101500 7Well 08 - -2 --4/14/2004 -------------------Well 08 - -2 --5/12/2004 -------------------Well 08 - 0.2 <2 505.36/2/2005 1200 750 -<5076311303.4 190 140 270220 0.93 <10 3300<100 781500 <5Well 08 - ---57/18/2005 -------------------Well 08 - 0.3 2 20-9/22/2005 1330 820 -10763415731971732502000.99 9 5040.6 101400 6Well 08 - 0.2 2 20-3/29/2006 1300 840 -20723214132041622502100.99 5 5035.2 101400 5Well 08 - 0.3 2 20-3/20/2007 1330 850 -10743316532031682602200.93 6 5037.8 101410 7Well 08 - ----9/27/2007 --------------70-10--Well 08 - ----12/4/2007 --------------50-10--Well 08 - ----4/9/2008 ------------0.95 ------Well 08 - 0.4 2 20-4/16/2008 1170 --1067 31 137 3 185 122 250210 0.99 7 7034 101400 6Well 08 - ----6/6/2008 ----- - - --- ----50-10--Well 08 - ----8/27/2008 ----- - - --- --0.84 -100-20--Well 08 - ----12/10/2008 ----- - - --- ----100-20--Well 08 - 0.27 2 50-2/18/2009 1400 760 -5080 37 160 3.1 200 180 260210 0.97 10 100100 20-7.8Well 08 - ----6/3/2009 ----- - - --- ----100-20--Well 08 - ----12/16/2009 ----- - - --- ----100-20--Well 08 - 0.25 2 50-2/10/2010 1500 890 -5087 40 170 3.3 210 220 250210 0.9 10 100100 201500 6.5Well 08 - ----5/10/2010 ----- - - --- ----100-20--Well 08 - ----8/18/2010 ----- - - --- ----100-20--Well 08 - ----9/15/2010 ----- - - --- --0.95 ------Well 08 - ----11/3/2010 ----- - - --- --0.953 ------Well 08 - ----12/8/2010 ----- - - --- --0.95 ------Well 08 - ----1/5/2011 ----- - - --- --0.9 ------Well 08 - 0.22 2.6 50-1/23/2013 1600 960 -5095 46 170 3.6 200 260 250200 0.72 10 100100 201500 6.8Well 08 - 0.26 2 50-5/29/2013 1600 --5097 46 190 3.8 220 280 240200 1.1 10 100100 20-10Well 08 - 0.25 2 50-6/17/2014 1600 1000 -5084 39 180 3.8 200 280 220180 -10 100100 201400 8.8Well 08 - 0.25 2 50-4/14/2015 1700 1000 -5094 44 190 3.5 210 300 250200 0.79 10 100100 201500 13Well 08 - 0.24 2 50-5/31/2016 1700 --5097 45 220 3.7 220 340 230190 0.84 10 100100 201700 11Well 08 - 0.27 2 50-9/7/2017 1700 1000 -5089 41 200 3.3 200 300 250200 0.79 10 100100 201600 7.1Well 08 - 0.27 2 50-5/9/2018 1700 1100 -5090 41 200 3.6 200 310 240200 0.79 10 100100 201600 13Well 08 - -<2 <50-5/6/2019 -1000 -<5096 44 200 -220 330 --0.82 <10 <100<100 <201600 6.9Well 08 - 0.3 2 20-7/19/2004 1370 850 -10101 42 108 3 143 187 310250 8.15 10 5044.6 101300 5Well 09 - Thursday, September 10, 2020Page 7 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood 0.3 2 40-3/30/2005 1380 870 -101094711231361863102508.1 11 5047.5 101400 4Well 09 - ----6/28/2005 ------------7.5 ------Well 09 - ----7/12/2005 ------------7.2 ------Well 09 - ----7/26/2005 ------------7.2 ------Well 09 - ----8/9/2005 ------------7.2 ------Well 09 - ----8/23/2005 ------------7.2 ------Well 09 - ----9/14/2005 ------------7.2 ------Well 09 - ----9/27/2005 ------------7.2 ------Well 09 - ----10/11/2005 ------------1.4 ------Well 09 - ----10/25/2005 ------------7.9 ------Well 09 - ----11/22/2005 ------------7.2 ------Well 09 - ----12/16/2005 ------------7.9 ------Well 09 - ----12/27/2005 ------------7.9 ------Well 09 - ----1/10/2006 ------------7.9 ------Well 09 - ----1/24/2006 ----- - - --- --7.9 ------Well 09 - ----2/14/2006 ----- - - --- --7.5 ------Well 09 - ----3/1/2006 ----- - - --- --7.7 ------Well 09 - ----3/14/2006 ----- - - --- --7.7 ------Well 09 - 0.1 2 40-3/29/2006 1360 860 -10103 44 108 2 142 192 280250 8.1 11 5045.8 101400 5Well 09 - ----5/17/2006 ----- - - --- --7.9 ------Well 09 - ----6/21/2006 ----- - - --- --7.5 ------Well 09 - ----7/19/2006 ----- - - --- --7.2 ------Well 09 - ----8/15/2006 ----- - - --- --7 ------Well 09 - ----9/20/2006 ----- - - --- --7 ------Well 09 - ----11/21/2006 ----- - - --- --7 ------Well 09 - ----1/17/2007 ----- - - --- --8.1 ------Well 09 - ----2/21/2007 ----- - - --- --8.4 ------Well 09 - 0.3 2 30-4/17/2007 1350 830 -10106 44 122 2 141 188 300250 8.09 8 6036.8 101510 4Well 09 - ----4/18/2007 ----- - - --- --8.1 ------Well 09 - ----5/16/2007 ----- - - --- --8.1 ------Well 09 - ----9/18/2007 ----- - - --- --10 ------Well 09 - ----10/17/2007 ----- - - --- --7.9 ------Well 09 - ----11/14/2007 ----- - - --- --7.7 ------Well 09 - ----2/6/2008 ----- - - --- --7.5 ------Well 09 - ----3/5/2008 ----- - - --- --7.7 ------Well 09 - 0.3 2 20-3/19/2008 1390 750 -1099 43 110 2 137 179 280230 -10 5047 101400 4Well 09 - ----4/2/2008 ----- - - --- --7.5 ------Well 09 - ----5/7/2008 ----- - - --- --7.7 ------Well 09 - Thursday, September 10, 2020Page 8 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood ----8/27/2008 ------------8.1 ------Well 09 - 0.26 2 50-2/18/2009 1300 840 -50110471102.6 130 190 300250 8.6 14 100100 20-5Well 09 - 0.25 2 50-2/10/2010 1400 810 -50110481202.6 140 190 310260 7.9 11 100100 201600 5Well 09 - 0.23 2 50-2/16/2011 1400 810 -50110471102.6 140 190 300250 7.9 11 100100 201500 5.6Well 09 - 0.28 2 50-5/16/2012 1400 800 -50100461102.6 390 200 290240 22 12 100100 20-5Well 09 - 0.28 2 50-5/29/2013 1400 840 -50100461202.5 140 190 280230 7.9 10 100100 20-5Well 09 - 0.26 2 50-6/19/2014 1400 840 -50110451102.6 140 190 250210 8.1 10 100100 201400 5.7Well 09 - 0.25 2 50-4/15/2015 1400 --50100451102.5 150 190 300240 8.4 10 100100 201400 5.7Well 09 - 0.25 2 50-6/1/2016 1400 850 -50110471102.6 160 210 290240 8.8 10 100100 201600 5Well 09 - 0.25 <2 <50-5/5/1995 1109 645 7.5 <5082371101.2 114 127 235235 3.66 <10 <100<100 <20-<5Well 11 - 0.3 <2 <50-10/26/1995 1325 688 -<50159.4 10.2 156.6 3.2 155 152.7 275275 5.6 <10 <100184 <201500 <5Well 11 - 0.2 <2 <50-6/30/1999 1370 850 -201084711041641683302707.25 9 <10063 <201400 3Well 11 - 0.2 <2 <50-12/20/2000 1620 980 -<501235811752032143502909.13 6 <10072.8 <201300 5Well 11 - ----5/21/2001 ------------8.6 ------Well 11 - ----5/25/2001 ----- - - --- --9.5 ------Well 11 - ----6/1/2001 ----- - - --- --9.5 ------Well 11 - ----6/10/2001 ----- - - --- --10 ------Well 11 - ----6/13/2001 ----- - - --- --8.8 ------Well 11 - ----6/28/2001 ----- - - --- --9.5 ------Well 11 - ----7/6/2001 ----- - - --- --8.6 ------Well 11 - ----7/12/2001 ----- - - --- --8.8 ------Well 11 - ----7/19/2001 ----- - - --- --8.6 ------Well 11 - ----7/26/2001 ----- - - --- --8.6 ------Well 11 - 0.3 <2 <50-8/1/2001 1450 950 -<50109 50 113 4 186 187 340280 7.86 9 <10067.2 <201360 3Well 11 - ----8/2/2001 ----- - - --- --8.4 ------Well 11 - ----9/13/2001 ----- - - --- --8.1 ------Well 11 - ----9/28/2001 ----- - - --- --8.6 ------Well 11 - 0.2 -20-10/10/2001 1440 890 --121 53 103 5 174 190 340280 7.9 -50-101510 -Well 11 - ----10/12/2001 ----- - - --- --8.6 ------Well 11 - ----11/27/2001 ----- - - --- --8.1 ------Well 11 - ----12/13/2001 ----- - - --- --9.9 ------Well 11 - ----12/18/2001 ----- - - --- --10 ------Well 11 - ----1/8/2002 ----- - - --- --9.3 ------Well 11 - ----1/22/2002 ----- - - --- --9.7 ------Well 11 - ----2/12/2002 ----- - - --- --9.5 ------Well 11 - ----2/26/2002 ----- - - --- --9.3 ------Well 11 - ----3/13/2002 ----- - - --- ---------Well 11 - Thursday, September 10, 2020Page 9 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood ----5/8/2002 ------------8.72 ------Well 11 - ----5/22/2002 ------------7.84 ------Well 11 - ----6/11/2002 ------------7.7 ------Well 11 - 0.2 2 20-7/24/2002 1430 890 -101074810941571763402807.41 8 5067.4 101310 3Well 11 - ----8/13/2002 ------------7.9 ------Well 11 - ----8/14/2002 ------------7 ------Well 11 - ----1/9/2003 ------------9.5 ------Well 11 - ----1/28/2003 ------------9.3 ------Well 11 - ----2/11/2003 ------------9.7 ------Well 11 - ----2/27/2003 ------------9.5 ------Well 11 - ----3/13/2003 ------------9.3 ------Well 11 - ----3/27/2003 ------------9.3 ------Well 11 - ----4/8/2003 ------------8.6 ------Well 11 - 0.2 2 20-4/17/2003 1540 960 -101225412051922153502809.53 9 5070 101390 4Well 11 - ----4/22/2003 ----- - - --- --8.6 ------Well 11 - ----6/5/2003 ----- - - --- --9.3 ------Well 11 - ----7/8/2003 ----- - - --- --8.1 ------Well 11 - ----7/23/2003 ----- - - --- --7.9 ------Well 11 - ----8/14/2003 ----- - - --- --7.5 ------Well 11 - ----9/9/2003 ----- - - --- --7.9 ------Well 11 - ----10/14/2003 ----- - - --- --7.5 ------Well 11 - ----10/28/2003 ----- - - --- --7.2 ------Well 11 - ----11/13/2003 ----- - - --- --9.3 ------Well 11 - -2 --11/19/2003 ----- - - --- ---------Well 11 - ----12/11/2003 ----- - - --- --8.4 ------Well 11 - ----12/23/2003 ----- - - --- --9.7 ------Well 11 - ----1/15/2004 ----- - - --- --8.6 ------Well 11 - ----1/28/2004 ----- - - --- --9 ------Well 11 - ----2/26/2004 ----- - - --- --8.4 ------Well 11 - ----3/11/2004 ----- - - --- --9.3 ------Well 11 - -2 --3/18/2004 ----- - - --- ---------Well 11 - ----4/13/2004 ----- - - --- --7.7 ------Well 11 - -2 --4/14/2004 ----- - - --- ---------Well 11 - ----4/27/2004 ----- - - --- --8.4 ------Well 11 - ----5/11/2004 ----- - - --- --8.4 ------Well 11 - 0.3 2 20-5/12/2004 1470 940 -10114 50 108 4 192 190 330270 -8 8062.3 101400 4Well 11 - ----5/25/2004 ----- - - --- --8.4 ------Well 11 - ----6/8/2004 ----- - - --- --8.1 ------Well 11 - Thursday, September 10, 2020Page 10 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood ----7/13/2004 ------------8.1 ------Well 11 - ----7/27/2004 ------------8.1 ------Well 11 - ----8/10/2004 ------------8.4 ------Well 11 - ----8/24/2004 ------------7.9 ------Well 11 - ----9/14/2004 ------------7.7 ------Well 11 - ----9/28/2004 ------------7.7 ------Well 11 - ----10/12/2004 ------------8.8 ------Well 11 - ----10/26/2004 ------------9.5 ------Well 11 - ----11/16/2004 ------------9.5 ------Well 11 - ----11/23/2004 ------------9.5 ------Well 11 - ----1/11/2005 ------------9 ------Well 11 - ----1/27/2005 ------------9.7 ------Well 11 - ----2/23/2005 ------------9.7 ------Well 11 - ----3/8/2005 ------------9.7 ------Well 11 - ----3/22/2005 ----- - - --- --9.3 ------Well 11 - 0.3 2 20-3/30/2005 1510 990 -10126 55 119 4 186 187 350280 8.4 8 5058.4 101400 4Well 11 - ----4/12/2005 ----- - - --- --8.6 ------Well 11 - ----4/26/2005 ----- - - --- --8.1 ------Well 11 - ----5/10/2005 ----- - - --- --9.5 ------Well 11 - ----5/24/2005 ----- - - --- --8.4 ------Well 11 - ----6/14/2005 ----- - - --- --8.1 ------Well 11 - ----6/28/2005 ----- - - --- --8.4 ------Well 11 - ----7/12/2005 ----- - - --- --8.1 ------Well 11 - ----7/26/2005 ----- - - --- --8.1 ------Well 11 - ----8/9/2005 ----- - - --- --7.9 ------Well 11 - ----8/23/2005 ----- - - --- --8.1 ------Well 11 - ----9/14/2005 ----- - - --- --7.9 ------Well 11 - ----9/27/2005 ----- - - --- --8.1 ------Well 11 - ----10/11/2005 ----- - - --- --7.5 ------Well 11 - ----10/25/2005 ----- - - --- --7.9 ------Well 11 - ----11/22/2005 ----- - - --- --9 ------Well 11 - ----12/16/2005 ----- - - --- --8.8 ------Well 11 - ----12/27/2005 ----- - - --- --9.9 ------Well 11 - ----1/10/2006 ----- - - --- --9.9 ------Well 11 - ----1/24/2006 ----- - - --- --9.9 ------Well 11 - ----2/14/2006 ----- - - --- --9.7 ------Well 11 - ----3/1/2006 ----- - - --- --9.9 ------Well 11 - ----3/14/2006 ----- - - --- --9.7 ------Well 11 - Thursday, September 10, 2020Page 11 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood 0.2 2 20-3/29/2006 1650 1020 -10132581194220224360290-7 5066.2 101300 5Well 11 - ----4/11/2006 ------------10 ------Well 11 - ----4/25/2006 ------------10 ------Well 11 - ----5/17/2006 ------------9 ------Well 11 - ----6/21/2006 ------------8.4 ------Well 11 - ----7/19/2006 ------------8.1 ------Well 11 - ----8/15/2006 ------------7.9 ------Well 11 - ----9/20/2006 ------------7.7 ------Well 11 - ----10/18/2006 ------------9.9 ------Well 11 - ----12/20/2006 ------------9.9 ------Well 11 - ----1/17/2007 ------------10 ------Well 11 - ----2/21/2007 ------------11 ------Well 11 - ----3/21/2007 ------------10 ------Well 11 - ----4/18/2007 ------------10 ------Well 11 - ----5/8/2007 ----- - - --- --10.5 ------Well 11 - ----5/23/2007 ----- - - --- --9.8 ------Well 11 - ----5/30/2007 ----- - - --- --9.69 ------Well 11 - ----6/12/2007 ----- - - --- --9.83 ------Well 11 - ----6/19/2007 ----- - - --- --9.7 ------Well 11 - ----7/17/2007 ----- - - --- --10.2 ------Well 11 - ----8/21/2007 ----- - - --- --9 ------Well 11 - 0.3 2 20-10/10/2007 1480 950 -10118 51 126 4 194 192 340280 8.52 9 5057.6 101400 4Well 11 - ----10/17/2007 ----- - - --- --9.5 ------Well 11 - ----11/14/2007 ----- - - --- --9.7 ------Well 11 - ----3/5/2008 ----- - - --- --9.9 ------Well 11 - 0.3 2 20-3/12/2008 1660 950 -10132 58 110 4 200 207 340280 -9 8066.3 101400 4Well 11 - ----4/2/2008 ----- - - --- --9.7 ------Well 11 - ----5/7/2008 ----- - - --- --8.8 ------Well 11 - ----6/3/2008 ----- - - --- --8.1 ------Well 11 - ----8/27/2008 ----- - - --- --9.7 ------Well 11 - ----12/4/2008 ----- - - --- --11 ------Well 11 - ----2/4/2009 ----- - - --- --11 ------Well 11 - 0.27 2 50-2/19/2009 1700 1100 -50150 64 120 4.6 230 220 350290 10 10 100100 20-5Well 11 - ----4/1/2009 ----- - - --- --11 ------Well 11 - ----5/6/2009 ----- - - --- --11 ------Well 11 - ----6/3/2009 ----- - - --- --11 ------Well 11 - ----7/8/2009 ----- - - --- --10 ------Well 11 - ----7/15/2009 ----- - - --- --9.7 ------Well 11 - Thursday, September 10, 2020Page 12 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood ----8/12/2009 ------------11 ------Well 11 - ----11/18/2009 ------------11 ------Well 11 - ----12/2/2009 ------------11 ------Well 11 - ----1/6/2010 ------------10 ------Well 11 - 0.29 2 50-2/10/2010 1700 1100 -50150651204.7 240 230 350290 11 10 100100 201400 5Well 11 - ----2/17/2010 ------------10 ------Well 11 - ----5/12/2010 ------------11 ------Well 11 - ----6/16/2010 ------------11 ------Well 11 - ----7/14/2010 ------------11 ------Well 11 - ----8/18/2010 ------------11 ------Well 11 - ----9/15/2010 ------------11 ------Well 11 - ----11/3/2010 ------------11 ------Well 11 - ----12/8/2010 ------------11 ------Well 11 - ----1/5/2011 ------------11 ------Well 11 - 0.26 2 50-2/16/2011 1800 1100 -50150 67 120 4.8 140 140 350290 6.3 10 100100 201300 6.2Well 11 - ----3/2/2011 ----- - - --- --10 ------Well 11 - ----4/27/2011 ----- - - --- --11 ------Well 11 - ----5/18/2011 ----- - - --- --11 ------Well 11 - ---5.27/30/2014 ----- - - --- ---------Well 11 - 0.2 <2 <50-12/18/1997 840 500 -<5059 23 80 3 110 88 240200 1.2 8 <10032 <201800 3Well 12 - 0.2 <2 <50-7/7/1999 864 510 -<5061 24 85 4 103 89 250200 1.2 10 <10036.7 <201700 3Well 12 - 0.1 <2 <50-12/20/2000 894 --<5060 25 90 3 113 100 240190 1.6 8 <10036 <201800 3Well 12 - -<2 --8/1/2001 ---<50- - - --- ---10 -37.3 --3Well 12 - 0.2 -<50-8/8/2001 842 500 --58 23 79 3 109 88 230190 1.2 -110-<201800 -Well 12 - 0.1 2 20-7/24/2002 872 530 -1060 24 86 3 100 96 250200 1.3 9 5043.6 101670 3Well 12 - ----8/14/2002 ----- - - --- --1.3 ------Well 12 - 0.1 2 20-4/17/2003 889 530 -1061 24 84 3 113 97 240200 1.7 9 5037.8 101780 3Well 12 - -2 --11/19/2003 ----- - - --- ---------Well 12 - -2 --3/18/2004 ----- - - --- ---------Well 12 - -2 --4/14/2004 ----- - - --- ---------Well 12 - 0.2 2 20-5/12/2004 880 550 -1060 24 81 3 107 97 240200 1.6 9 7036.3 101700 3Well 12 - 0.2 2 20-3/30/2005 886 540 -1065 25 86 3 101 89 240200 1.5 10 5037.4 101800 2Well 12 - 0.2 2 20-3/20/2007 895 540 -1061 23 87 2 106 99 240200 1.7 9 5034.2 101740 2Well 12 - 0.1 2 20-3/19/2008 878 470 -1055 22 77 3 100 93 220180 1.3 9 5037.7 101700 3Well 12 - ----4/16/2008 ----- - - --- --2 ------Well 12 - ----8/27/2008 ----- - - --- --1.3 -100-20--Well 12 - 0.19 2 50-2/19/2009 870 530 -5061 24 84 2.7 100 94 230190 1.6 10 100100 20-5Well 12 - Thursday, September 10, 2020Page 13 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood 0.2 2 50-2/10/2010 900 540 -506526862.8 100 99 240200 2 10 100100 201900 5Well 12 - 0.18 2 50-2/16/2011 920 530 -506326842.8 100 100 240190 2 10 100100 201900 5Well 12 - 0.22 2 50-5/16/2012 900 530 -506326852.8 110 100 230190 2.3 10 100100 20-5Well 12 - 0.2 2 50-5/29/2013 910 570 -506326882.7 110 100 230190 2.2 10 100100 20-5Well 12 - 0.19 2 50-6/19/2014 920 560 -506426852.9 110 100 200160 2.2 10 100100 201800 5Well 12 - ---8.47/30/2014 -------------------Well 12 - 0.18 2 50-4/15/2015 860 520 -505724822.8 110 97 220180 1.7 10 100100 201700 5Well 12 - 0.18 2 50-6/1/2016 920 580 -5065279031101102301902.4 10 100100 202100 5Well 12 - 0.1 <2 <50-12/17/1997 720 440 -<503310994110681501200.93 11 15029 <201700 3Well 13 - ---1.53/12/1998 -------------18.5 -----Well 13 - 0.1 <2 <50-7/7/1999 767 470 -<504214883107721901801.2 14 <10032 <201600 3Well 13 - 0.1 <2 <50-6/8/2000 800 490 -<504515923108742001701.3 14 <10034.6 <201700 3Well 13 - 0.2 ---8/29/2001 775 460 --47 16 97 4 111 73 200170 -------Well 13 - ----2/21/2002 ------------1.6 ------Well 13 - 0.1 2 20-8/21/2002 776 --1046 15 102 4 113 82 210170 1.2 13 5033.7 101590 4Well 13 - 0.1 2 20-4/17/2003 791 490 -1045 15 96 4 118 78 210170 1.4 13 5033.1 101680 3Well 13 - -2 --11/19/2003 ----- - - --- ---------Well 13 - -2 --3/18/2004 ----- - - --- ---------Well 13 - -2 --4/14/2004 ----- - - --- ---------Well 13 - -2 --5/12/2004 ----- - - --- ---------Well 13 - 0.2 2 20-6/2/2004 788 500 -2046 15 94 3 112 79 210170 1.4 13 5034.9 101600 3Well 13 - 0.2 2 20-3/30/2005 797 510 -1048 16 97 3 105 74 210170 1.3 14 5033.6 101700 3Well 13 - 0.1 2 20-3/29/2006 805 550 -1061 15 90 3 105 84 230200 1.6 13 5032.7 101800 3Well 13 - 0.2 2 20-3/20/2007 821 490 -1047 16 99 3 112 85 210170 1.7 12 10032.9 101640 3Well 13 - 0.1 2 20-3/12/2008 827 --1046 15 90 3 105 82 200160 2 14 5035 101600 3Well 13 - ----4/16/2008 ----- - - --- --1.7 ------Well 13 - ----8/27/2008 ----- - - --- --2 -100-20--Well 13 - 0.14 2 50-2/19/2009 810 460 -5050 17 97 3.3 110 83 220180 1.7 12 100100 20-5Well 13 - 0.15 2 50-2/10/2010 820 490 -5049 17 97 3.2 110 83 210170 1.8 13 100100 201800 5Well 13 - 0.15 2.3 50-2/16/2011 830 490 -5048 17 100 3.5 110 81 220180 1.7 17 150100 201900 5Well 13 - 0.16 2 50-5/16/2012 820 490 -5048 18 96 3.3 120 91 200170 2.1 13 100100 20-5Well 13 - 0.16 2 50-5/29/2013 840 520 -5050 18 100 3.3 110 88 200170 2.1 14 100100 20-5Well 13 - 0.15 2 50-6/19/2014 860 520 -5051 18 95 3.2 110 91 200160 2.2 10 100100 201700 5Well 13 - 0.15 2 50-4/15/2015 860 --5052 19 99 3.3 120 91 220180 2.3 10 100100 201800 5Well 13 - 0.16 2 50-8/16/2017 920 570 -5060 22 96 3.3 110 100 220180 2.9 10 100100 331800 5Well 13 - 0.15 2 50-5/9/2018 850 520 -5051 18 93 3.2 110 90 200170 2.2 12 100100 201700 5Well 13 - 0.16 <2 <50-5/9/2019 -510 -<5052 18 94 3.5 110 89 --2.2 12 <100<100 -1700 <5Well 13 - Thursday, September 10, 2020Page 14 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood 0.4 <2 50-11/3/2000 1400 880 -<5075381903.5 300 120 -210 1.2 <10 100<100 301400 <5Well 14 - ----2/27/2002 ------------1.9 ------Well 14 - 0.2 4 50-3/6/2002 1430 900 -10653118133081292602101.7 9 5033.6 101190 11Well 14 - 0.3 3 20-6/4/2002 1370 --50683317743131232702201.6 7 18030.1 101120 11Well 14 - 0.3 4 20-9/11/2002 1430 950 -10723417452691232602201.7 8 5032.2 101240 11Well 14 - 0.4 3 20-12/11/2002 1440 --10703319243101392602202.51 7 5032.8 101270 14Well 14 - -3 --11/19/2003 -------------------Well 14 - -2 --3/18/2004 -------------------Well 14 - -3 --4/14/2004 -------------------Well 14 - -2 --5/12/2004 -------------------Well 14 - 0.6 3 20-6/2/2004 1500 940 -20733419433131542502102.82 5 5032.1 101300 11Well 14 - 0.4 3 20-3/30/2005 1560 1030 -10803720833081692502102.64 6 8033.8 101300 13Well 14 - 0.4 3 20-3/29/2006 1580 1010 -10753418833141831701403.5 4 5031.2 101300 12Well 14 - 0.5 3 20-3/20/2007 1600 1040 -10743622243101922502003.98 5 5032.6 101400 14Well 14 - 0.4 4 20-3/12/2008 1680 1000 -1078 36 210 3 300 204 230190 3.46 6 6036 101300 17Well 14 - ----4/9/2008 ----- - - --- --3.8 ------Well 14 - ----8/27/2008 ----- - - --- --4.1 ------Well 14 - 0.34 4 50-2/24/2009 1500 1300 -5071 34 180 3.4 310 190 330270 4.5 10 100100 20-18Well 14 - 0.38 3.3 50-2/10/2010 1600 930 -5081 38 200 3.3 300 190 240200 4.3 10 100100 201400 15Well 14 - 0.35 4.1 50-2/16/2011 1600 980 -5079 39 190 3.3 170 100 240200 2.5 10 100100 201300 18Well 14 - 0.39 3.4 50-5/16/2012 1400 930 -5078 38 170 3.2 310 180 240200 -10 100100 20-17Well 14 - 0.35 3 50-5/29/2013 1500 990 -5082 40 200 3.5 300 180 210170 -10 100100 20-20Well 14 - 0.38 3.8 50-6/19/2014 1500 960 -5078 38 180 3.3 280 180 220180 4.3 10 100100 201200 16Well 14 - 0.4 3 50-4/14/2015 1400 --5077 37 170 3.2 290 170 240200 4.1 10 100100 201100 20Well 14 - 0.37 3.5 50-10/5/2016 1600 980 -5077 37 180 3.2 290 190 240200 4 10 100100 201100 18Well 14 - 0.39 2.9 50-9/7/2017 1500 940 -5078 39 180 3.2 280 180 250200 4.2 10 100100 201200 13Well 14 - 0.37 3.4 50-5/10/2018 1500 1000 -5084 40 170 3.5 300 180 240200 4.2 10 100100 201100 21Well 14 - -3.2 <50-5/9/2019 -990 -<5089 - 180 3.8 320 180 --4 <10 <100<100 <201200 16Well 14 - 0.3 2 20-7/26/2006 1030 630 -1067 29 98 2 132 101 280230 2.37 6 5030.5 101500 4Well 15 - ----8/15/2006 ----- - - --- --2.2 ------Well 15 - ----9/20/2006 ----- - - --- --2.3 ------Well 15 - ----10/18/2006 ----- - - --- --7 ------Well 15 - ----12/20/2006 ----- - - --- --6.3 ------Well 15 - ----1/17/2007 ----- - - --- --6.3 ------Well 15 - ----2/21/2007 ----- - - --- --6.8 ------Well 15 - 0.3 2 20-4/17/2007 1210 740 -1091 40 113 3 150 148 280230 6.12 9 8032.7 101500 4Well 15 - ----4/18/2007 ----- - - --- --6.3 ------Well 15 - Thursday, September 10, 2020Page 15 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood ----5/2/2007 ------------6.08 ------Well 15 - ----6/27/2007 ------------6.01 ------Well 15 - ----7/24/2007 ------------6.44 ------Well 15 - ----8/21/2007 ------------6.8 ------Well 15 - ----10/17/2007 ------------6.3 ------Well 15 - ----11/14/2007 ------------6.1 ------Well 15 - ----1/23/2008 ------------6.1 ------Well 15 - ----2/27/2008 ------------5.2 ------Well 15 - 0.5 4 20-4/16/2008 1640 950 -10793721032902002001803.5 6 6034.7 101300 18Well 15 - ----4/30/2008 ------------5.4 ------Well 15 - ----8/27/2008 ------------3.8 ------Well 15 - 0.25 2 50-2/24/2009 1200 980 -9369331203.1 170 160 240200 4.3 10 100100 20-6.3Well 15 - 0.3 2 50-2/10/2010 1000 590 -507132992.4 54 40 280230 0.99 10 100100 201600 5Well 15 - ----9/15/2010 ------------2.58 ------Well 15 - ----12/8/2010 ----- - - --- --4.25 ------Well 15 - ----1/5/2011 ----- - - --- --2.5 ------Well 15 - 0.25 2 50-2/16/2011 1100 650 -5074 34 100 2.6 130 110 280230 2.73 10 100100 201600 5.7Well 15 - ----3/2/2011 ----- - - --- --2.28 ------Well 15 - ----4/27/2011 ----- - - --- --2.42 ------Well 15 - 0.29 2 50-5/16/2012 1100 --5075 35 100 2.6 160 140 260220 2.5 10 100100 20-5.6Well 15 - 0.29 2 50-5/29/2013 1100 --5073 34 110 2.5 140 120 260210 2.7 10 100100 20-5.9Well 15 - 0.27 2 50-6/30/2014 1100 --5080 34 99 2.6 140 120 260220 3.8 10 100100 201400 5.3Well 15 - 0.24 2 50-4/15/2015 1400 840 -5096 44 120 2.7 180 200 270220 6.8 10 100100 201400 6.5Well 15 - 0.26 2 50-6/1/2016 1100 710 -5079 36 110 2.6 140 120 270220 3.4 10 100100 201700 5Well 15 - ----9/14/2016 ----- - - --- --3.1 ------Well 15 - ----12/7/2016 ----- - - --- --4.9 ------Well 15 - ----3/27/2017 ----- - - --- --3.2 ------Well 15 - ----5/10/2017 ----- - - --- --6 ------Well 15 - ----8/16/2017 ----- - - --- --4.4 ------Well 15 - 0.28 2 50-9/7/2017 1100 670 -5078 34 99 2.6 140 120 280230 3.2 10 100100 201600 6.7Well 15 - ----12/12/2017 ----- - - --178 ---------Well 15 - ----12/13/2017 ----- - - --- --6.7 ------Well 15 - ----2/21/2018 ----- - - --- --7.2 ------Well 15 - 0.29 2 50-5/10/2018 1000 660 -5073 32 96 2.4 140 110 270220 3 10 100100 201600 7.4Well 15 - ----9/26/2018 ----- - - --- --3 ------Well 15 - ----11/7/2018 ----- - - --- --2.7 ------Well 15 - ----3/11/2019 ----- - - --- --2.7 ------Well 15 - 0.26 <2 --5/9/2019 -720 -<5083 36 120 2.9 150 150 --3 <10 <100<100 -1600 6.4Well 15 - Thursday, September 10, 2020Page 16 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer City of Brentwood ----6/19/2019 ------------3 ------Well 15 - ----12/9/2019 ------------2.9 ------Well 15 - Diablo Water District 0.4 ---4/25/2003 -910 7.9 -80 46 170 3.9 270 210 -199 0.94878 ---64--CREEKSIDE MW - 0.3 3 50-5/4/2004 930 --506031100216072-240 <0.5 10 100100 20-5Glen Park Well - ---1.47/5/2006 993 620 ---------------1200 -Glen Park Well - 0.1 2 501.610/19/2006 1000 620 -5067321072.3 170 80 230230 0.54 10 100100 381400 5Glen Park Well - ----12/26/2006 -------------------Glen Park Well - ---1.61/23/2007 -----------------1400 -Glen Park Well - ---1.64/18/2007 -----------------1200 -Glen Park Well - 0.3 3.7 50-6/23/2010 1100 -7.6 5052361002.7 180 100 230230 0.93 10 100100 34-5Glen Park Well - ----6/22/2011 ------------1.1 ------Glen Park Well - ----7/26/2011 1082 661 -------108 ---------Glen Park Well - ----6/20/2012 ----- - - --- --0.81 ------Glen Park Well - 0.2 2.6 50-6/19/2013 1000 --5070 36 100 2.4 160 90 230230 1.6 10 100100 20-5Glen Park Well - ----6/18/2014 ----- - - --- --1.1 ------Glen Park Well - ---1.77/30/2014 ----- - - --- ---------Glen Park Well - ----8/12/2014 ----21 14 82 3.3 -- ---------Glen Park Well - ----3/18/2015 ----- - - --- --0.79 ------Glen Park Well - ----3/23/2016 ----- - - --- --1.2 ------Glen Park Well - -2 50-6/22/2016 1018 690 -5072 37 110 -180 110 226226 -10 100100 20-5Glen Park Well - ----3/20/2019 ----- - - --- --1.5 ------Glen Park Well - 0.3 ND ND-6/19/2019 -695 -ND71 37 120 -170 120 --1.4 ND NDND 23-NDGlen Park Well - 0.3 <2 50ND6/6/2006 940 560 -<5056 24 100 1.4 110 88 330270 ND <10 21063 1401800 <5South Park PW - ---110/19/2006 ----- - - --- ---------South Park PW - ----3/18/2015 ----- - - --- --<0.5 ------South Park PW - 0.3 2 50-6/17/2015 950 570 ND 5064 29 120 1.9 100 92 270270 -10 310100 140-5South Park PW - -2 50-6/22/2016 -690 -5072 37 110 -180 110 ---10 100100 20-5South Park PW - ----6/21/2017 ----60 - - --- ---------South Park PW - 0.33 4.8 50-5/10/2010 1000 640 -5058 33 110 2.2 180 85 256210 0.77 10 100100 471300 5Stonecreek PW - ----7/26/2011 1151 742 --- - - --123 ---------Stonecreek PW - ----5/23/2012 1100 730 --- - - --- --1.7 ---120--Stonecreek PW - 0.2 4.3 50-6/19/2013 1200 --5078 41 130 2.9 190 130 210210 1.9 10 100100 100-5Stonecreek PW - ----7/10/2013 ----- - - --- ------93--Stonecreek PW - ----6/18/2014 ----- - - --- --1.9 ------Stonecreek PW - Thursday, September 10, 2020Page 17 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer Diablo Water District ---17/30/2014 -------------------Stonecreek PW - ----3/23/2016 ------------1.91 ------Stonecreek PW - -3.9 50-6/22/2016 1146 --507740130-190 150 220220 -10 100100 99-5Stonecreek PW - ----12/20/2017 ----62 --------------Stonecreek PW - ----3/20/2019 ------------0.91 ------Stonecreek PW - 0.3 3.9 --6/19/2019 -734 -ND6437120-180 130 --1.3 ND NDND 100-NDStonecreek PW - 0.3 ---10/23/2000 -570 7.8 -58 34 100 2.3 160 74 --0.74547 ------Glen Park MW - Town of Discovery Bay 0.22 ---3/19/2013 1000 590 7.86 -25 12 180 1.5 52 86 330330 <0.45 -<100-120--1BMW-343 - 0.32 ---3/20/2013 1000 580 7.62 -64 31 120 1.5 110 120 250250 <0.45 -<100-120--4AMW-357 - 0.36 ---3/19/2013 1100 650 7.84 -11 7.4 250 1.3 33 84 430430 <0.45 -<100-120--6MW-250 - 0.29 ---3/19/2013 1000 550 7.84 -29 14 190 1.8 44 88 350350 <0.45 -<100-100--6MW-350 - 0.46 ---3/20/2013 950 540 7.93 -26 17 170 1.4 96 85 280280 <0.45 -<100-190--7MW-330 - ----3/28/1995 ----- - - --- --0.36 ------WELL 01B - 0.26 <2 <50-5/9/1996 900 550 -<5042 18 130 1.7 84 90 300--<10 210110 140-<5WELL 01B - ND -<50-3/10/1997 920 670 --40 19 160 2 94 100 360290 ND -80-1402100 -WELL 01B - 0.3 2 50-5/10/1999 892 592 -2439 23 126 -79 78 260260 <0.05 2 110110 120-1WELL 01B - --50-5/17/2000 864 598 -5041 19 119 -88 80 288288 <0.1 -77-125--WELL 01B - -<2 <50-7/10/2001 920 560 -<5045 18 130 2 66 76 260260 <2.3 -<100110 130-<5WELL 01B - ---ND5/28/2002 ----- - - --- -------2200 -WELL 01B - 0.37 <2 --10/16/2002 900 --<5041 18 140 1.7 83 80 354290 ND ------WELL 01B - ---ND10/29/2002 ----- - - --- -------2100 -WELL 01B - ----3/18/2003 ----- - - --- ----130-140--WELL 01B - ----6/3/2003 ----- - - --- ----<100-130--WELL 01B - ----6/10/2003 ----- - - --- ----<100-130--WELL 01B - ----6/17/2003 ----- - - --- ----<100-120--WELL 01B - ----6/24/2003 ----- - - --- ----<100-130--WELL 01B - ----7/1/2003 ----- - - --- ----<100-110--WELL 01B - ----7/8/2003 ----- - - --- ----<100-120--WELL 01B - ----7/15/2003 ----- - - --- ----<100-140--WELL 01B - ----7/23/2003 ----- - - --- ----<100-130--WELL 01B - ----7/29/2003 ----- - - --- ----<100-130--WELL 01B - ----8/5/2003 ----- - - --- ----<100-140--WELL 01B - ----8/12/2003 ----- - - --- ----<100-130--WELL 01B - Thursday, September 10, 2020Page 18 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer Town of Discovery Bay ----8/19/2003 --------------<100-130--WELL 01B - ----9/23/2003 --------------<100-130--WELL 01B - ----11/25/2003 --------------220-460--WELL 01B - ----1/28/2004 --------------200-120--WELL 01B - ----4/7/2004 --------------<100-130--WELL 01B - ----4/14/2004 --------------<100-130--WELL 01B - ----4/21/2004 --------------120-130--WELL 01B - ----5/26/2004 --------------90-122--WELL 01B - ----6/9/2004 --------------90-120--WELL 01B - ----6/23/2004 --------------70-116--WELL 01B - ----6/30/2004 --------------90-124--WELL 01B - ----7/7/2004 --------------80-92.8--WELL 01B - ----7/14/2004 --------------80-108--WELL 01B - ----7/21/2004 --------------80-125--WELL 01B - ----7/28/2004 ----- - - --- ----70-127--WELL 01B - ----8/4/2004 ----- - - --- ----80-120--WELL 01B - ----8/11/2004 ----- - - --- ----90-121--WELL 01B - ----8/18/2004 ----- - - --- ----80-114--WELL 01B - ----8/25/2004 ----- - - --- ----70-122--WELL 01B - ----9/1/2004 ----- - - --- ----80-121--WELL 01B - ----9/8/2004 ----- - - --- ----80-120--WELL 01B - ----9/15/2004 ----- - - --- ----80-118--WELL 01B - ----9/22/2004 ----- - - --- ----70-122--WELL 01B - ----9/29/2004 ----- - - --- ----80-120--WELL 01B - ----10/6/2004 ----- - - --- ----80-124--WELL 01B - ----10/13/2004 ----- - - --- ----80-123--WELL 01B - ----10/20/2004 ----- - - --- ----80-115--WELL 01B - 0.3 2 20-12/29/2004 898 550 -5043 18 128 2 89 85 330270 -1 220115 1202300 2WELL 01B - ----5/4/2005 ----- - - --- ----80-121--WELL 01B - ----10/12/2005 ----- - - --- ----90-120--WELL 01B - 0.3 2 20-12/19/2005 906 540 -1043 18 125 2 85 82 330270 <0.09 1 80114 1302200 2WELL 01B - ----12/21/2005 ----- - - --- ----780-140--WELL 01B - ----1/25/2006 ----- - - --- ----70-120--WELL 01B - ----2/8/2006 ----- - - --- ----70-120--WELL 01B - ----2/22/2006 ----- - - --- ----80-130--WELL 01B - ----3/15/2006 ----- - - --- ----110-130--WELL 01B - ----4/19/2006 ----- - - --- ----110-120--WELL 01B - ----5/3/2006 ----- - - --- ----100-130--WELL 01B - Thursday, September 10, 2020Page 19 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer Town of Discovery Bay ----5/17/2006 --------------150-130--WELL 01B - ----5/31/2006 --------------60-130--WELL 01B - ----6/27/2006 --------------50-120--WELL 01B - ----7/12/2006 --------------110-130--WELL 01B - ----7/19/2006 --------------80-100--WELL 01B - ----7/26/2006 --------------140-110--WELL 01B - ----8/23/2006 --------------130-140--WELL 01B - ----9/13/2006 --------------110-140--WELL 01B - ----9/28/2006 --------------90-130--WELL 01B - ----10/4/2006 ------------<0.09 -110-140--WELL 01B - ----10/11/2006 --------------100-130--WELL 01B - ----10/25/2006 --------------110-130--WELL 01B - ----11/8/2006 --------------100-130--WELL 01B - 0.3 <2 --10/7/2008 ---<50--------ND <10 -110 --<5WELL 01B - 0.19 <2 <50-3/10/2009 890 560 -<5042 18 130 2 85 86 320260 ND <10 <100120 130-<5WELL 01B - ----8/25/2009 ----- - - --- ----<100-120--WELL 01B - ----3/3/2010 930 ---- - - --- --ND ------WELL 01B - ---ND12/29/2010 ----- - - --- ---------WELL 01B - ----11/8/2011 ----- - - --- --ND ------WELL 01B - 0.2 2 20-11/20/2012 936 550 -2048 19 135 2 84 81 320260 <0.09 4 150120 1402100 2WELL 01B - ----7/8/2013 ----- - - --- --<0.09 ------WELL 01B - ----11/26/2013 ----- - - --- --<0.09 ------WELL 01B - ----8/20/2014 ----- - - --- --0.1 ------WELL 01B - ---0.512/17/2014 ----- - - --- ---------WELL 01B - 0.2 2 60-3/11/2015 941 560 -1040 17 124 2 82 82 310260 0.09 1 240121 1302200 1WELL 01B - ----4/27/2016 ----- - - --- --0.1 ------WELL 01B - ---16/14/2017 ----- - - --- --0.4 ------WELL 01B - 0.2 2 50-4/13/2018 937 540 -5043 19 138 2 88.2 86 320260 0.4 10 100116 1302200 5WELL 01B - ----5/23/2019 ----- - - --- --<0.4 ------WELL 01B - 0.33 1 10-11/19/1986 600 532 --31.5 14.1 193 1.8 65 95 512420 <0.02 20 120100 123-1WELL 02 - 0.29 10 50-9/12/1989 929 605 -10049.2 19.5 111 2.4 83.7 118 279270 <0.2 10 144100 120-5WELL 02 - 0.2 <2 <50-1/20/1993 1000 560 -<5028 14 2 170 74 96 357293 -<10 120<100 200-<5WELL 02 - ----3/28/1995 ----- - - --- ---------WELL 02 - ----5/8/1996 ----- - - --- --0.09 ------WELL 02 - 0.1 -<50-3/10/1997 960 ---50 20 170 1 92 120 350290 ND -150-1202000 -WELL 02 - 0.26 2 50-5/10/1999 921 --2342 19 134 -86 81 274274 <0.05 2 120100 130-1WELL 02 - --50-5/17/2000 886 592 -7642 17 118 -88 84 291291 <0.1 -175-134--WELL 02 - Thursday, September 10, 2020Page 20 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer Town of Discovery Bay -<2 <50-7/10/2001 940 560 -<50441814026683280280<2.3 -120110 140-<5WELL 02 - ---ND5/28/2002 -----------------2000 -WELL 02 - 0.31 <2 <50ND12/11/2002 890 570 -<5042191601.6 74 87 366300 ND <10 140110 1402200 <5WELL 02 - ----3/18/2003 --------------200-140--WELL 02 - ----3/25/2003 --------------100-130--WELL 02 - ----4/2/2003 --------------130-130--WELL 02 - ----4/8/2003 --------------120-130--WELL 02 - ----4/15/2003 --------------140-130--WELL 02 - ----4/22/2003 --------------<100-130--WELL 02 - ----4/29/2003 --------------<100-120--WELL 02 - ----5/6/2003 --------------<100-120--WELL 02 - ----5/20/2003 --------------<100-130--WELL 02 - ----5/27/2003 --------------<100-120--WELL 02 - ----10/27/2004 --------------90-116--WELL 02 - 0.3 2 30-12/29/2004 942 570 -1040 18 142 2 85 96 350290 -1 90131 1202100 2WELL 02 - 0.3 2 20-12/19/2005 925 560 -1039 17 136 2 74 87 340280 <0.09 1 90106 1202200 2WELL 02 - ----10/4/2006 ----- - - --- --<0.09 ------WELL 02 - 0.39 2.4 --10/7/2008 ---<50- - - --- --ND <10 -100 --<5WELL 02 - 0.19 <2 54-3/10/2009 950 590 -<5040 18 140 2 80 100 330270 ND <10 <100110 120-<5WELL 02 - ----8/25/2009 ----- - - --- ----<100-120--WELL 02 - ----3/3/2010 980 ---- - - --- --ND ------WELL 02 - ---ND12/29/2010 ----- - - --- ---------WELL 02 - ----11/8/2011 ----- - - --- --ND ------WELL 02 - 0.1 2 30-11/20/2012 982 550 -1043 18 153 2 77 90 340280 <0.09 4 170110 1402100 2WELL 02 - ----7/8/2013 ----- - - --- --<0.09 ------WELL 02 - ----11/26/2013 ----- - - --- --<0.09 ------WELL 02 - ----8/20/2014 ----- - - --- --0.09 ------WELL 02 - ---0.512/17/2014 ----- - - --- ---------WELL 02 - 0.2 2 20-3/11/2015 964 560 -1033 16 145 1 65 86 330270 <0.09 1 140100 1102200 1WELL 02 - ----4/27/2016 ----- - - --- --0.1 ------WELL 02 - ---16/14/2017 ----- - - --- --0.4 ------WELL 02 - 0.2 3 50-4/13/2018 959 550 -5035 17 159 2 71.7 88 350290 0.4 10 130100 1202300 5WELL 02 - ----5/23/2019 ----- - - --- --<0.4 ------WELL 02 - 0.37 <2 <50-8/1/1996 1000 --<5049 23 110 1 97 84 270-ND <10 60<100 90-<5WELL 04A - 0.2 -<50-3/10/1997 1000 590 --20 10 230 ND 80 130 420340 --170-803000 -WELL 04A - 0.31 2 50-5/10/1999 905 600 -4252 24 110 -99 84 244244 -2 100100 100-1WELL 04A - --50-5/17/2000 874 602 -5048 26 106 -105 85 265265 <0.1 -62-95--WELL 04A - Thursday, September 10, 2020Page 21 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer Town of Discovery Bay -2 <50-7/10/2001 910 600 -<50562612028680250250<2.3 -<100<100 110-<5WELL 04A - ---ND5/28/2002 -----------------2100 -WELL 04A - ----8/20/2002 --------------<100-110--WELL 04A - 0.42 ---10/16/2002 910 520 --51 26 120 1.4 100 87 317260 ND -<100-110--WELL 04A - ----10/23/2002 --------------<100-100--WELL 04A - ----10/24/2002 --------------<100-100--WELL 04A - ---ND10/29/2002 --------------<100-1102000 -WELL 04A - ----10/30/2002 --------------<100-110--WELL 04A - ----11/5/2002 --------------<100-100--WELL 04A - ----11/6/2002 --------------<100-99--WELL 04A - ----11/12/2002 --------------<100-110--WELL 04A - ----11/19/2002 --------------<100-120--WELL 04A - ----11/20/2002 --------------<100-110--WELL 04A - ----12/3/2002 --------------<100-100--WELL 04A - ----12/10/2002 ----- - - --- ----<100-110--WELL 04A - ----12/17/2002 ----- - - --- ----<100-110--WELL 04A - ----12/23/2002 ----- - - --- ----<100-110--WELL 04A - ----12/30/2002 ----- - - --- ----<100-110--WELL 04A - ----1/7/2003 ----- - - --- ----<100-110--WELL 04A - ----1/14/2003 ----- - - --- ----<100-110--WELL 04A - ----1/21/2003 ----- - - --- ----<100-110--WELL 04A - ----2/11/2003 ----- - - --- ----150-110--WELL 04A - ----2/18/2003 ----- - - --- ----<100-100--WELL 04A - ----2/25/2003 ----- - - --- ----<100-88--WELL 04A - ----3/5/2003 ----- - - --- ----120-120--WELL 04A - ----3/11/2003 ----- - - --- ----<100-110--WELL 04A - ----3/18/2003 ----- - - --- ----330-110--WELL 04A - ----3/25/2003 ----- - - --- ----<100-110--WELL 04A - ----4/2/2003 ----- - - --- ----<100-100--WELL 04A - ----4/8/2003 ----- - - --- ----<100-100--WELL 04A - ----4/15/2003 ----- - - --- ----<100-110--WELL 04A - ----4/22/2003 ----- - - --- ----<100-110--WELL 04A - ----4/29/2003 ----- - - --- ----<100-110--WELL 04A - ----5/6/2003 ----- - - --- ----<100-110--WELL 04A - ----5/20/2003 ----- - - --- ----<100-110--WELL 04A - ----5/27/2003 ----- - - --- ----<100-110--WELL 04A - ----6/3/2003 ----- - - --- ----<100-110--WELL 04A - ----6/10/2003 ----- - - --- ----<100-110--WELL 04A - Thursday, September 10, 2020Page 22 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer Town of Discovery Bay ----6/17/2003 --------------<100-110--WELL 04A - ----6/24/2003 --------------<100-110--WELL 04A - ----7/1/2003 --------------<100-110--WELL 04A - ----7/8/2003 --------------<100-110--WELL 04A - ----7/15/2003 --------------<100-110--WELL 04A - ----7/23/2003 --------------<100-110--WELL 04A - ----7/29/2003 --------------<100-110--WELL 04A - ----8/5/2003 --------------<100-120--WELL 04A - ----8/12/2003 --------------<100-110--WELL 04A - ----8/19/2003 --------------<100-110--WELL 04A - ----9/23/2003 --------------<100-120--WELL 04A - ----11/25/2003 --------------<100-110--WELL 04A - ----1/28/2004 --------------<100-97--WELL 04A - ----4/7/2004 --------------<100-110--WELL 04A - ----4/14/2004 ----- - - --- ----<100-110--WELL 04A - ----4/21/2004 ----- - - --- ----<100-<20--WELL 04A - ----5/26/2004 ----- - - --- ----70-102--WELL 04A - ----6/9/2004 ----- - - --- ----50-98.4--WELL 04A - ----6/23/2004 ----- - - --- ----50-98.5--WELL 04A - ----6/30/2004 ----- - - --- ----70-99.9--WELL 04A - ----7/7/2004 ----- - - --- ----60-88.4--WELL 04A - ----7/14/2004 ----- - - --- ----70-93.7--WELL 04A - ----7/21/2004 ----- - - --- ----60-105--WELL 04A - ----7/28/2004 ----- - - --- ----60-104--WELL 04A - ----8/4/2004 ----- - - --- ----70-102--WELL 04A - ----8/11/2004 ----- - - --- ----70-101--WELL 04A - ----8/18/2004 ----- - - --- ----60-94.8--WELL 04A - ----8/25/2004 ----- - - --- ----60-99.7--WELL 04A - ----9/1/2004 ----- - - --- ----50-149--WELL 04A - ----9/8/2004 ----- - - --- ----60-101--WELL 04A - ----9/15/2004 ----- - - --- ----60-98.9--WELL 04A - ----9/22/2004 ----- - - --- ----90-100--WELL 04A - ----9/29/2004 ----- - - --- ----50-137--WELL 04A - ----10/6/2004 ----- - - --- ----50-150--WELL 04A - ----10/13/2004 ----- - - --- ----50-137--WELL 04A - ----10/20/2004 ----- - - --- ----100-92--WELL 04A - ----10/27/2004 ----- - - --- ----70-101--WELL 04A - 0.3 2 20-12/29/2004 924 590 -1050 24 116 1 100 94 320260 <0.09 1 6094.4 1102100 2WELL 04A - Thursday, September 10, 2020Page 23 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer Town of Discovery Bay ----5/4/2005 --------------60-100--WELL 04A - ----9/21/2005 --------------90-100--WELL 04A - ----10/12/2005 --------------50-40--WELL 04A - 0.3 2 20-12/19/2005 930 580 -10502411119790320260<0.09 1 6076.1 1102100 2WELL 04A - ----12/21/2005 --------------380-110--WELL 04A - ----1/25/2006 --------------2770-400--WELL 04A - ----2/8/2006 --------------60-100--WELL 04A - ----2/22/2006 --------------260-110--WELL 04A - ----3/15/2006 --------------730-80--WELL 04A - ----4/5/2006 --------------50-50--WELL 04A - ----4/19/2006 --------------150-100--WELL 04A - ----5/3/2006 --------------60-110--WELL 04A - ----5/17/2006 --------------140-110--WELL 04A - ----5/31/2006 --------------60-110--WELL 04A - ----6/27/2006 ----- - - --- ----70-160--WELL 04A - ----7/12/2006 ----- - - --- ----90-100--WELL 04A - ----7/19/2006 ----- - - --- ----80-100--WELL 04A - ----7/26/2006 ----- - - --- ----90-110--WELL 04A - ----8/23/2006 ----- - - --- ----70-110--WELL 04A - ----9/13/2006 ----- - - --- ----110-110--WELL 04A - ----9/28/2006 ----- - - --- ----80-100--WELL 04A - ----10/4/2006 ----- - - --- ----100-110--WELL 04A - ----10/11/2006 ----- - - --- ----100-110--WELL 04A - ----10/25/2006 ----- - - --- ----110-100--WELL 04A - ----11/8/2006 ----- - - --- ----80-100--WELL 04A - 0.4 <2 --10/7/2008 ---<50- - - --- ---<10 -<100 --<5WELL 04A - 0.26 2.7 <50-3/10/2009 920 580 -<5050 25 120 2 96 94 300250 -<10 <100<100 110-<5WELL 04A - ----8/25/2009 ----- - - --- ----<100-98--WELL 04A - ----3/3/2010 960 ---- - - --- --ND ------WELL 04A - ----8/2/2011 ----- - - --- --ND ------WELL 04A - 0.3 2 20-11/19/2012 963 580 -1051 26 124 2 98 96 300250 <0.09 1 5081.5 1102100 3WELL 04A - ----7/8/2013 ----- - - --- --0.2 ------WELL 04A - ----11/26/2013 ----- - - --- --<0.09 ------WELL 04A - ----8/20/2014 ----- - - --- --0.2 ------WELL 04A - ---0.512/18/2014 ----- - - --- ---------WELL 04A - 1.5 2 20-3/12/2015 954 --1050 24 111 1 98 97 300250 0.1 1 4080.3 1002200 3WELL 04A - ----4/27/2016 ----- - - --- --0.1 ------WELL 04A - ---16/14/2017 ----- - - --- --0.4 ------WELL 04A - Thursday, September 10, 2020Page 24 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer Town of Discovery Bay 0.3 3 50-4/13/2018 1000 600 -50532712611081053002500.4 10 100100 1102200 5WELL 04A - ----5/23/2019 ------------<0.4 ------WELL 04A - 0.4 10 50-3/28/1990 985 753 -10026.3 17.8 138 2.3 84.4 98.9 307307 <0.2 10 131100 146-5WELL 05A - 0.3 <2 <50-1/20/1993 820 570 -<50231319028399370303ND <10 70<100 140-<5WELL 05A - ----3/28/1995 ------------ND ------WELL 05A - --<50-6/14/1996 1000 590 --29 15 180 0.41 85 71 340340 --<100-0.13--WELL 05A - 0.2 -<50-3/10/1997 1000 630 --30 17 200 ND 89 120 380310 ND -50-1502700 -WELL 05A - 0.39 2 50-5/10/1999 1010 667 -253017174-79 95 310310 <0.05 2 140100 140-1WELL 05A - --50-5/17/2000 977 660 -502918163-86 113 318318 <0.1 -106-141--WELL 05A - -3 <50-7/10/2001 1100 640 -<503417180279100320320<2.3 -<100<100 150-<5WELL 05A - ---ND5/28/2002 -----------------3100 -WELL 05A - 0.43 <2 <50-10/16/2002 930 530 -<5051261201.4 100 91 329270 ND <10 380<100 57-<5WELL 05A - ---ND10/29/2002 -----------------2000 -WELL 05A - 0.4 4 20-12/29/2004 1190 750 -103618203179130450370<0.09 1 8094.2 503400 2WELL 05A - 0.3 2 20-12/19/2005 949 580 -1049 24 117 1 97 100 310260 <0.09 1 15082.2 102100 2WELL 05A - ----10/4/2006 ----- - - --- --<0.09 ------WELL 05A - 0.46 3.3 --10/7/2008 ---<50- - - --- --<0.7 <10 -<100 --<5WELL 05A - 0.33 2.7 <50-6/9/2009 970 560 -<5049 24 120 2 96 96 320260 ND <10 110<100 <20-<5WELL 05A - ----3/3/2010 1000 ---- - - --- --0.81 ------WELL 05A - ---ND12/29/2010 ----- - - --- ---------WELL 05A - ----8/2/2011 ----- - - --- --ND ------WELL 05A - 0.2 5 20-11/19/2012 2220 1240 -1071 35 401 3 74 480 410340 <0.09 2 160225 1404000 9WELL 05A - 0.32 ---3/20/2013 2200 1100 7.97 -65 38 360 2.2 81 470 350350 <0.45 -<100-13--WELL 05A - ----4/24/2013 2840 1520 --- - - --- --0.014 -50-312--WELL 05A - ----7/8/2013 ----- - - --- --<0.09 ------WELL 05A - ----11/26/2013 ----- - - --- --<0.09 ------WELL 05A - ---0.512/18/2014 ----- - - --- ---------WELL 05A - 0.1 4 20-3/12/2015 2190 --1080 39 293 2 85 480 370300 0.2 1 190206 503500 6WELL 05A - ----4/27/2016 ----- - - --- --0.1 ------WELL 05A - ---16/14/2017 ----- - - --- --0.4 ------WELL 05A - 0.3 5 50-4/13/2018 2660 1470 -5075 41 442 3 83 594 430350 0.4 10 100302 5604100 8WELL 05A - ----5/23/2019 ----- - - --- --<0.4 ------WELL 05A - 0.3 <2 <50-8/24/2009 930 --<5032 15 160 2 62 90 360310 ND <10 <100100 110-<5WELL 06 - ---ND12/29/2010 ----- - - --- ---------WELL 06 - ----7/20/2011 900 ---- - - --- ---------WELL 06 - ----11/8/2011 950 ---- - - --- ---------WELL 06 - ----11/30/2011 980 ---- - - --- ---------WELL 06 - Thursday, September 10, 2020Page 25 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer Town of Discovery Bay 0.34 <2 <50-2/28/2012 900 520 -<503114160ND5989360290ND <10 <100120 100-<5WELL 06 - 0.2 2 20-11/20/2012 974 570 -10341517225092310260-4 7097 1102500 2WELL 06 - ----7/17/2013 ------------<0.09 ------WELL 06 - ----11/26/2013 ------------<0.09 ------WELL 06 - ----8/20/2014 ------------0.09 ------WELL 06 - ---0.512/17/2014 -------------------WELL 06 - 0.2 2 20-3/11/2015 978 560 -10271316124789370300-1 10093.9 1002600 1WELL 06 - ----4/27/2016 ------------0.1 ------WELL 06 - ---16/14/2017 ------------0.4 ------WELL 06 - 0.3 2 50-4/13/2018 1000 --502914189240.8 97 400320 0.4 10 100100 1003000 5WELL 06 - ----5/23/2019 ------------<0.4 ------WELL 06 - 0.5 2 20-7/30/2015 951 580 -103318153182882902400.1 1 10073.1 1702500 1WELL 07 - ---0.58/26/2015 -------------------WELL 07 - ----7/20/2016 ------------0.1 ------WELL 07 - ----6/14/2017 ----- - - --- --0.4 ------WELL 07 - ---17/26/2017 ----- - - --- ---------WELL 07 - 0.4 3 50-4/13/2018 1250 720 -5045 25 193 2 85.2 165 370300 0.4 10 140110 2102900 5WELL 07 - ---17/24/2018 ----- - - --- ---------WELL 07 - ----5/23/2019 ----- - - --- --<0.4 ------WELL 07 - ---<17/9/2019 ----- - - --- ---------WELL 07 - BEACON WEST 0.1 28 50-6/17/2009 1500 ---37 25 240 3.1 140 250 260260 -10 100120 180-5Well 1 - 0.1 35 50-5/23/2012 1300 --5027 23 24 3.2 150 260 220220 -10 100150 250-5Well 1 - ---18/20/2014 ----- - - --- ---------Well 1 - ND 33 50-6/17/2015 1400 --5037 23 230 2.8 140 240 230230 -10 100120 200-5Well 1 - ----3/23/2016 ----- - - --- --ND ------Well 1 - ----12/20/2017 ----- - - --- --0.4 ------Well 1 - ----4/17/2018 ----- - - --- ------20--Well 1 - KNIGHTSEN COMMUNITY WATER SYSTEM ----10/19/2006 ----- - - --- ---------Knightsen Town Well - 0.2 2 50-6/17/2009 890 ---59 29 87 1.9 140 69 200200 1.2 10 100100 20-5Knightsen Town Well - ----6/23/2010 ----- - - --- --1.2 ------Knightsen Town Well - ----6/22/2011 ----- - - --- --1.2 ------Knightsen Town Well - 0.3 2 50-5/23/2012 790 --17043 24 85 2.1 140 68 230230 0.99 10 100100 20-5Knightsen Town Well - ----6/18/2014 ----- - - --- --0.59 ------Knightsen Town Well - Thursday, September 10, 2020Page 26 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer KNIGHTSEN COMMUNITY WATER SYSTEM ---2.68/20/2014 -------------------Knightsen Town Well - ----3/18/2015 ------------0.47 ------Knightsen Town Well - 0.5 2 50-6/17/2015 850 550 -506026891.9 120 59 240240 -10 100100 20-5Knightsen Town Well - ----3/23/2016 ------------0.62 ------Knightsen Town Well - ----12/20/2017 ------------0.45 ------Knightsen Town Well - 0.3 <2 <50-6/20/2018 ---<506126841.8 120 62 --0.43 <10 <100<100 <20-<5Knightsen Town Well - KNIGHTSEN ELEMENTARY SCHOOL 0.2 12.5 <50-6/18/2007 880 --<5030101301.2 110 59 300240 -<10 <100<100 92-<5WELL 3 - -14 --12/6/2007 -------------------WELL 3 - -13 --3/20/2008 -------------------WELL 3 - -14 --7/7/2008 -------------------WELL 3 - -13 --9/23/2008 -------------------WELL 3 - -12 --12/15/2008 -------------------WELL 3 - -12 --3/11/2009 ----- - - --- ---------WELL 3 - -13 --6/10/2009 ----- - - --- ---------WELL 3 - -14 --9/10/2009 ----- - - --- ---------WELL 3 - -13 --12/3/2009 ----- - - --- ---------WELL 3 - -14 --3/3/2010 ----- - - --- ---------WELL 3 - ND ---4/7/2010 ----- - - --- ---------WELL 3 - 0.3 10 <50-6/3/2010 890 --5029 10 140 1.3 110 59 290240 -1 100100 100-<5WELL 3 - -16 --9/9/2010 ----- - - --- ---------WELL 3 - -13 --12/1/2010 ----- - - --- ---------WELL 3 - -14 --3/9/2011 ----- - - --- ---------WELL 3 - 0.3 12 <50-6/13/2011 860 --5030 11 140 1.5 110 60 270220 -1 <100100 94-<5WELL 3 - -14 --9/7/2011 ----- - - --- ---------WELL 3 - -11 --12/5/2011 ----- - - --- ---------WELL 3 - -14 --3/1/2012 ----- - - --- ---------WELL 3 - -14 --6/5/2012 ----- - - --- ---------WELL 3 - -12.7 --9/5/2012 ----- - - --- ---------WELL 3 - -15 --12/10/2012 ----- - - --- ---------WELL 3 - -12.3 --3/11/2013 ----- - - --- ---------WELL 3 - -13 --6/6/2013 ----- - - --- ---------WELL 3 - -13 --9/9/2013 ----- - - --- ---------WELL 3 - -15 --12/12/2013 ----- - - --- ---------WELL 3 - -12 --3/6/2014 ----- - - --- ---------WELL 3 - -11 --6/4/2014 ----- - - --- ---------WELL 3 - -14 --9/4/2014 ----- - - --- ---------WELL 3 - Thursday, September 10, 2020Page 27 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer KNIGHTSEN ELEMENTARY SCHOOL -14 --12/8/2014 -------------------WELL 3 - -13 --3/23/2015 -------------------WELL 3 - -14 --6/25/2015 -------------------WELL 3 - -14 --9/14/2015 -------------------WELL 3 - ----10/19/2015 ------------ND ------WELL 3 - -12 --12/14/2015 -------------------WELL 3 - ----1/27/2016 ------------ND ------WELL 3 - -12.8 --3/9/2016 -------------------WELL 3 - ----4/6/2016 ------------ND ------WELL 3 - -12.6 --6/6/2016 -------------------WELL 3 - ----7/12/2016 ------------ND ------WELL 3 - -15 --9/13/2016 -------------------WELL 3 - ----10/17/2016 ------------ND ------WELL 3 - -14 --12/12/2016 -------------------WELL 3 - ----1/18/2017 ----- - - --- --ND ------WELL 3 - -2 --12/13/2017 ----- - - --- ---------WELL 3 - SUGAR BARGE MARINA ----1/17/2002 ----- - - --- --ND ------Bethel Island - ----1/22/2004 ----- - - --- --<0.5 ------Bethel Island - ----1/24/2005 ----- - - --- --ND ------Bethel Island - ----1/23/2006 ----- - - --- --ND ------Bethel Island - ----1/22/2007 ----- - - --- --ND ------Bethel Island - ----1/10/2008 ----- - - --- --ND ------Bethel Island - ----1/12/2009 ----- - - --- --ND ------Bethel Island - ----1/14/2010 ----- - - --- --ND ------Bethel Island - ----1/9/2012 ----- - - --- --ND ------Bethel Island - ----1/8/2014 ----- - - --- --ND ------Bethel Island - ----1/21/2015 ----- - - --- --ND ------Bethel Island - ----1/4/2016 ----- - - --- --<0.4 ------Bethel Island - ----1/11/2017 ----- - - --- --<0.4 ------Bethel Island - ----1/17/2018 ----- - - --- --<0.4 ------Bethel Island - WILLOW MOBILE HOME PARK ----11/11/2004 ----- - - --- --8.8 ------Well Head - 0.19 <2 50-5/24/2006 1100 660 --96 64 38 0.7 78 110 420340 9 -100-20-<5Well Head - 0.1 2 50-6/17/2009 1900 ---51 28 270 3.9 120 350 220220 <0.5 10 100160 150-5Well Head - Thursday, September 10, 2020Page 28 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep Aquifer WILLOW MOBILE HOME PARK ----6/23/2010 ------------<0.5 ------Well Head - ----12/18/2012 ---50---------1 -100 ---Well Head - ----7/31/2014 ------------ND ------Well Head - 0.1 <2 <50-7/15/2015 1700 1000 -5049252804.3 130 340 260220 ND <10 <100190 160-<5Well Head - ----7/20/2017 ------------0.44 ------Well Head - ----7/10/2018 ------------ND ------Well Head - ND 2.1 <50-8/7/2018 1700 1000 -<5048243004.1 130 340 260210 ND <10 <100170 130-<5Well Head - WILLOW PARK MARINA 0.1 10 50-6/17/2009 1500 ---24 12 260 2.7 130 200 250250 <0.5 10 100100 110-5East Well - ----6/23/2010 ------------<0.5 ------East Well - ----6/22/2011 ------------<0.5 ------East Well - 0.1 12 50-5/23/2012 1300 --5017122203140210260260<0.5 10 110100 140-5East Well - ----6/19/2013 ------------<0.5 ------East Well - ----6/18/2014 ----- - - --- --<0.5 ------East Well - ---18/20/2014 ----- - - --- ---------East Well - ----3/18/2015 ----- - - --- --<0.5 ------East Well - 0.2 12 50-6/17/2015 1400 840 -5024 13 260 2.6 130 200 270270 -10 100100 120-5East Well - ----3/23/2016 ----- - - --- --ND ------East Well - ----12/20/2017 ----- - - --- --0.4 ------East Well - 0.15 -<50-6/20/2018 -842 -<5024 12 240 -130 200 --<0.4 <10 110<100 120-<5East Well - ----3/20/2019 ----- - - --- --ND ------East Well - 0.1 ---6/14/2009 1300 ---- - - -120 170 300300 <0.5 ------West Well - 0.1 10 50-6/17/2009 1300 ---23 13 240 2.7 120 170 300300 <0.5 10 100100 100-5West Well - ----6/23/2010 ----- - - --- --<0.5 ------West Well - ----6/22/2011 ----- - - --- --<0.5 ------West Well - 0.1 12 50-5/23/2012 1100 --5016 12 220 3 120 180 260260 <0.5 10 100100 130-5West Well - ----6/19/2013 ----- - - --- --<0.5 ------West Well - ----6/18/2014 ----- - - --- --<0.5 ------West Well - ---18/20/2014 ----- - - --- ---------West Well - ----3/18/2015 ----- - - --- --<0.5 ------West Well - 0.2 10 50-6/17/2015 1300 760 -5022 12 230 2.5 120 170 270270 -10 110100 110-5West Well - ----3/23/2016 ----- - - --- --ND ------West Well - ----12/20/2017 ----- - - --- --0.4 ------West Well - 0.15 12 <50-6/20/2018 -772 -<5023 12 210 2.6 120 170 --<0.4 <10 -<100 110-<5West Well - Composite Aquifer Thursday, September 10, 2020Page 29 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Composite Aquifer City of Brentwood 0.4 ---4/26/1999 -390 --61 21 54 1 39 68 -210 2.07828 ---140400 -MW-14 Shallow - 0.35 10 50-8/16/1990 1530 934 -14396.9 53.8 96.6 2.7 153 226 304304 9.53 15 102100 10-5WELL 02 - 0.33 10 50-8/16/1990 1460 939 -13994.7 49.9 96.2 3 186 203 242242 9.15 10 100100 10-5WELL 04 - 0.45 <2 250-6/29/1994 1700 900 -14013049130-310 170 -230 3.2 9 220<100 20-<5Well 10A - 0.42 <2 55-11/10/1994 1895 1289 -5216877142-339 245 -305 1.99 <10 4449 <20-<5Well 10A - 0.4 8 <50-7/7/1999 1730 1180 -6012968135133241893703005.35 2 10053.2 <201400 8Well 10A - 0.2 8 <50-12/27/2000 1740 1140 -1012271137143492013302705.72 3 10054.4 <201400 7Well 10A - 0.3 6 20-8/1/2001 1780 1230 -<5011967139133351873703005.67 4 <10052.1 <201350 6Well 10A - -7 --11/19/2003 -------------------Well 10A - 0.3 6 20-3/30/2005 1760 1190 -1013873141123101754003305.6 3 5050.5 101400 5Well 10A - 0.3 -20-6/15/2005 1800 1250 --136 73 139 13 362 198 390320 5.6 -260-101400 -Well 10A - ----7/26/2005 ------------6.1 ------Well 10A - ----8/9/2005 ------------7 ------Well 10A - ----8/23/2005 ----- - - --- --7 ------Well 10A - ----10/11/2005 ----- - - --- --6.1 ------Well 10A - ----10/25/2005 ----- - - --- --6.1 ------Well 10A - ----12/27/2005 ----- - - --- --5.4 ------Well 10A - ----1/10/2006 ----- - - --- --6.1 ------Well 10A - ----1/24/2006 ----- - - --- --6.1 ------Well 10A - ----2/14/2006 ----- - - --- --6.1 ------Well 10A - ----3/1/2006 ----- - - --- --5.9 ------Well 10A - ----3/14/2006 ----- - - --- --6.1 ------Well 10A - ----4/11/2006 ----- - - --- --6.1 ------Well 10A - ----4/25/2006 ----- - - --- --6.1 ------Well 10A - ----5/17/2006 ----- - - --- --6.3 ------Well 10A - ----6/21/2006 ----- - - --- --6.6 ------Well 10A - ----7/19/2006 ----- - - --- --6.1 ------Well 10A - ----9/20/2006 ----- - - --- --6.3 ------Well 10A - ----10/18/2006 ----- - - --- --6.6 ------Well 10A - ----11/21/2006 ----- - - --- --6.8 ------Well 10A - ----12/20/2006 ----- - - --- --6.8 ------Well 10A - ----1/17/2007 ----- - - --- --7.2 ------Well 10A - ----2/21/2007 ----- - - --- --7.2 ------Well 10A - ----3/21/2007 ----- - - --- --6.8 ------Well 10A - ----4/18/2007 ----- - - --- --7.2 ------Well 10A - ----6/19/2007 ----- - - --- --6.1 ------Well 10A - ----9/18/2007 ----- - - --- --8.8 ------Well 10A - Thursday, September 10, 2020Page 30 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Composite Aquifer City of Brentwood 0.3 7 20-3/19/2008 1840 1120 -1013071138123201823903205.9 3 5053.5 101400 7Well 10A - ----4/2/2008 ------------6.3 ------Well 10A - ----5/7/2008 ------------6.3 ------Well 10A - ----8/27/2008 ------------6.3 ------Well 10A - 0.26 7.2 50-2/18/2009 1800 940 -5014076150133501803903206.3 10 100100 20-8.8Well 10A - 0.28 7 50-2/10/2010 1800 1200 --140 74 150 13 370 190 390320 6.3 10 100100 201500 7.3Well 10A - 0.24 7.8 50-2/16/2011 1800 1200 -5014075140132101103703003.6 10 100100 201500 10Well 10A - Diablo Water District ----4/18/1991 -------------------CORP YARD WELL 01 - 1.1 2.2 <50-1/7/1992 1400 940 7.4 0.00270431404.4 350 130 240240 1 <10 52<100 145.4800 2.4CORP YARD WELL 01 - 0.3 <2 20-7/13/1992 1750 1090 7.48 0.003110571705.1 430 160 240240 3.4 <10 <100<100 76900 <5CORP YARD WELL 01 - 0.32 3.3 <50-10/6/1992 -1040 7.5 7.769511805.2 420 150 243243 3.2 <10 <100<100 58900 <5CORP YARD WELL 01 - ND 2.1 34-4/5/1993 1440 920 7.8 <5088431404.7 360 140 230230 1.5 <10 <100<100 71<100 <5CORP YARD WELL 01 - ND 3.9 23-7/20/1993 1550 1030 7.57 <5074 46 178 4.8 420 150 247247 1.5 <10 25<100 180700 <5CORP YARD WELL 01 - ND 3.1 <50-10/5/1993 1490 970 7.62 <5085 60 140 4.6 390 140 239239 1.3 <10 <100<100 150740 <5CORP YARD WELL 01 - 0.21 5.2 <50-1/4/1994 1460 930 7.68 0.00482 37 160 4.7 360 140 236236 0.75 <10 <100<100 270860 <5CORP YARD WELL 01 - 0.26 3.7 <50-4/5/1994 1470 890 7.72 0.00281 48 150 4.4 320 140 240240 1.2 <10 <100<100 240650 <5CORP YARD WELL 01 - 0.34 2 50-12/8/1997 1780 1020 -6.685 53 150 4 390 180 245245 2.33 1 100100 62920 5CORP YARD WELL 01 - ND -<50-7/13/1999 1730 1120 7.63 -130 55 180 5 400 190 240240 2.9 -<100<100 -780 -CORP YARD WELL 01 - 0.33 4.2 50-8/8/2000 1680 1080 7.7 50119 58 184 6 360 200 234234 1.5 10 100100 62900 5CORP YARD WELL 01 - ----4/10/2001 --7.93 -- - - --- ---------CORP YARD WELL 01 - 1.5 4.5 50-6/18/2008 2400 -7.6 50190 83 190 6.5 570 240 290290 <0.5 10 100130 400-5CORP YARD WELL 01 - ----6/23/2010 ----- - - --- --5.9 ------CORP YARD WELL 01 - ----6/19/2013 ----- - - --- --5 ------CORP YARD WELL 01 - ----6/18/2014 ----- - - --- --4.7 ------CORP YARD WELL 01 - ----3/18/2015 ----- - - --- --4.7 ------CORP YARD WELL 01 - 0.28 5.4 50-6/21/2017 2200 --50150 72 250 5.5 550 220 400330 4.3 10 100100 370-5CORP YARD WELL 01 - ----3/20/2019 ----- - - --- --2.6 ------CORP YARD WELL 01 - Byron-Bethany Irrigation District -1 490-7/18/1974 1050 608 8.4 -32 16 176 3.1 114 91 -279 0.1 1 0.58-0.32500 -6 Byer - ----6/15/1976 1060 -8.3 -- -170 --96 -258 -------6 Byer - ----8/22/1978 1050 -8.5 -- -178 --100 -287 -------6 Byer - ----7/24/1980 1060 -8.8 -30 16 180 --100 -279 -------6 Byer - ----11/4/1980 1060 -8.5 -33 16 - --102 -281 -----3300 -6 Byer - ----5/6/1981 1060 -8.4 -31 15 183 --101 -280 -----3200 -6 Byer - Thursday, September 10, 2020Page 31 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Composite Aquifer Byron-Bethany Irrigation District ----11/17/1982 1080 -8.1 -34 17 183 2.2 -111 -287 -------6 Byer - ----8/14/1984 1150 691 8.4 -25 19 189 2.2 157 116 -246 -----3100 -6 Byer - ----9/11/1986 885 -8.2 -42 35 109 --55 -324 -------6 Byer - ----7/15/1988 940 -8.2 -50 38 113 --77 -322 -------6 Byer - ----8/16/1990 892 -8.2 -43 36 95 1.2 -105 -259 -------6 Byer - KNIGHTSEN ELEMENTARY SCHOOL ----9/20/2001 ------------0.5 ------NORTH WELL - ----3/14/2002 ------------ND ------NORTH WELL - ----9/9/2002 ------------0.77 ------NORTH WELL - ----4/29/2003 ------------ND ------NORTH WELL - ----7/16/2003 ------------0.54 ------NORTH WELL - ----9/30/2003 ---<50-----------<100 ---NORTH WELL - ----1/21/2004 ------------2.1 ------NORTH WELL - ----4/15/2004 ----- - - --- --ND ------NORTH WELL - 0.1 4.1 50-6/30/2004 1500 910 -<5099 62 120 2.6 210 180 390320 0.97 <10 120160 650-<5NORTH WELL - ----1/19/2005 ----- - - --- --0.43 ------NORTH WELL - ----3/16/2005 ----- - - --- ---------NORTH WELL - ----4/14/2005 ----- - - --- --<0.5 ------NORTH WELL - ----7/19/2005 ----- - - --- --1.7 ------NORTH WELL - -<2 --8/9/2013 ----- - - --- ---------NORTH WELL - -<2 --11/14/2014 ----- - - --- ---------NORTH WELL - ----9/20/2001 ----- - - --- --11 ------SOUTH WELL - ----3/14/2002 ----- - - --- --3.6 ------SOUTH WELL - ----9/9/2002 ----- - - --- --11 ------SOUTH WELL - ----12/2/2002 ----- - - --- --3.8 ------SOUTH WELL - ----4/29/2003 ----- - - --- --5.6 ------SOUTH WELL - ----7/16/2003 ----- - - --- --9.5 ------SOUTH WELL - ----10/13/2003 ----- - - --- --9.7 ------SOUTH WELL - ----4/15/2004 ----- - - --- --7.5 ------SOUTH WELL - 0.1 2.5 50-6/30/2004 1500 880 -<50100 62 120 2.6 210 180 390320 0.95 <10 150158 650-<5SOUTH WELL - ----7/29/2004 ----- - - --- --5.9 ------SOUTH WELL - ----10/18/2004 ----- - - --- --3.4 ------SOUTH WELL - ----1/27/2005 ----- - - --- --2 ------SOUTH WELL - ----3/21/2005 ----- - - --- ---------SOUTH WELL - -<2 --8/9/2013 ----- - - --- ---------SOUTH WELL - -<2 --11/14/2014 ----- - - --- ---------SOUTH WELL - Thursday, September 10, 2020Page 32 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Composite Aquifer KNIGHTSEN ELEMENTARY SCHOOL ---ND7/22/2015 -------------------SOUTH WELL - -<2 --3/7/2017 -------------------SOUTH WELL - -<2 --3/28/2017 ------------0.5 ------SOUTH WELL - -3.6 --4/10/2017 ------------0.9 ------SOUTH WELL - -<2 --6/13/2017 ------------2.21 ------SOUTH WELL - 0.15 <2 --8/9/2017 ---50--------2.7 <10 -110 --<5SOUTH WELL - -<2 --9/12/2017 -------------------SOUTH WELL - ----10/17/2017 ------------2.4 ------SOUTH WELL - ----1/16/2018 ------------1.7 ------SOUTH WELL - -<2 --3/7/2018 -------------------SOUTH WELL - ----4/25/2018 ------------1.6 ------SOUTH WELL - -<2 --6/12/2018 -------------------SOUTH WELL - ----7/11/2018 ------------2.1 ------SOUTH WELL - -<2 --9/18/2018 -------------------SOUTH WELL - ----10/10/2018 ----- - - --- --2.4 ------SOUTH WELL - -ND --12/19/2018 ----- - - --- ---------SOUTH WELL - -ND --3/27/2019 ----- - - --- ---------SOUTH WELL - ----4/10/2019 ----- - - --- --ND ------SOUTH WELL - ----8/1/2019 ----- - - --- --1.3 ------SOUTH WELL - -ND --9/11/2019 ----- - - --- ---------SOUTH WELL - -ND --12/19/2019 ----- - - --- ---------SOUTH WELL - Unknown Aquifer Town of Discovery Bay 0.3 3.5 10-11/19/1986 700 628 --25.7 12.5 236 1.52 58 110 525430 0.02 20 200100 146-1WELL 01 - 0.34 10 50-9/12/1989 1105 726 -10037 16 152 2.1 70.4 128 356356 0.2 10 260100 153-50WELL 01 - 0.2 <2 <50-1/20/1993 940 540 -11037 16 159 2 78 84 346284 ND <10 440<100 140-<5WELL 01 - ----3/28/1995 ----- - - --- --0.36 ------WELL 01 - 0.33 1 10-11/19/1986 600 528 --31.7 14.8 199 1.84 72 95 488400 <0.02 20 92100 120-3WELL 03 - 0.34 10 50-9/12/1989 939 691 -10041.2 16.6 125 2.5 79.7 115 293293 <0.2 10 100104 122-5WELL 03 - 0.2 <2 <50-1/20/1993 960 530 -<5030 14 172 2 67 90 351288 ND <10 170<100 120-<5WELL 03 - ----3/28/1995 ----- - - --- --ND ------WELL 03 - 0.2 -<50-3/10/1997 1000 570 --30 16 190 1 79 130 370300 ND -310-1202300 -WELL 03 - 0.3 <2 <50-1/20/1993 920 600 -<5026 13 189 2 80 100 366300 ND <10 100<100 80-<5WELL 04 - ANCHOR MARINA Thursday, September 10, 2020Page 33 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer ANCHOR MARINA ----7/9/2018 ------------ND ------Well Head - ANGLER S RANCH #3 ----6/27/2002 ------------ND ------WELL 02 - 0.1 8 --7/1/2002 ---<50--------ND --<100 --<5WELL 02 - ----6/23/2004 ------------ND ------WELL 02 - --50-8/25/2004 1400 800 --48 27 200 2.4 160 200 260210 --100-180--WELL 02 - ----6/23/2005 ------------ND ------WELL 02 - 0.2 8 50-7/25/2005 ---<50---------2.9 -<100 --<5WELL 02 - ----6/29/2007 ------------ND ------WELL 02 - --<50-9/5/2007 1400 870 --60 26 200 2.4 160 220 250210 --<100-160--WELL 02 - ----6/30/2009 ------------ND ------WELL 02 - ----6/27/2011 ------------ND ------WELL 02 - ----6/27/2012 ------------ND ------WELL 02 - 0.1 7.3 <50-9/20/2012 1600 --5057 30 210 2.9 180 270 250210 ND 1 <100100 220-<5WELL 02 - ----6/25/2013 ----- - - --- --ND ------WELL 02 - ----6/24/2014 ----- - - --- --ND ------WELL 02 - ---ND9/30/2014 ----- - - --- ---------WELL 02 - ----6/29/2015 ----- - - --- --ND ------WELL 02 - ----6/30/2016 ----- - - --- --ND ------WELL 02 - ----6/29/2017 ----- - - --- --ND ------WELL 02 - 0.1 7.6 <50ND7/24/2017 1600 950 -5063 29 220 2.8 180 290 250210 ND <10 <100100 210-<5WELL 02 - ----6/28/2018 ----- - - --- --ND ------WELL 02 - ----6/25/2019 ----- - - --- --ND ------WELL 02 - ANGLERS SUBDIVISION 4 ----2/13/2002 ----- - 235 --- ---------WELL 1 - 1696 Taylor - ----8/7/2002 ----- - 258 --- ---------WELL 1 - 1696 Taylor - ----2/5/2003 ----- - 251 --- ---------WELL 1 - 1696 Taylor - ----8/6/2003 ----- - - --- --<0.09 ------WELL 1 - 1696 Taylor - 0.2 3 60-7/21/2004 1770 1080 -1090 47 196 4 182 344 260220 <0.09 1 140127 3402000 3WELL 1 - 1696 Taylor - ----8/11/2004 ----- - 250 --- ---------WELL 1 - 1696 Taylor - ----9/15/2004 ----- - 208 --- ---------WELL 1 - 1696 Taylor - ----6/1/2005 ----- - 184 --- ---------WELL 1 - 1696 Taylor - -3 --6/22/2005 ----- - - --- ---------WELL 1 - 1696 Taylor - ----7/27/2005 ----- - - --- --<0.09 ------WELL 1 - 1696 Taylor - -3 --8/24/2005 ----- - - --- ---------WELL 1 - 1696 Taylor - Thursday, September 10, 2020Page 34 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer ANGLERS SUBDIVISION 4 ----7/19/2006 ------------0.2 ------WELL 1 - 1696 Taylor - ----2/7/2007 ------189 ------------WELL 1 - 1696 Taylor - 0.1 3 20-7/5/2007 1770 1090 -10864421141973572602100.1 1 190116 3201840 4WELL 1 - 1696 Taylor - ----2/15/2008 ------225 ------------WELL 1 - 1696 Taylor - ----7/3/2008 ------------0.25 ------WELL 1 - 1696 Taylor - ----9/11/2008 ------248 ------------WELL 1 - 1696 Taylor - ----7/17/2009 ------------0.1 ------WELL 1 - 1696 Taylor - 0.1 3 130-7/20/2010 1610 980 -10814120441662982502000.1 1 220127 2901900 4WELL 1 - 1696 Taylor - ----7/20/2011 ------------<0.09 ------WELL 1 - 1696 Taylor - ----7/26/2012 ------------<0.09 ------WELL 1 - 1696 Taylor - 0.1 4 20-7/9/2013 2130 --10117612484216510240200<0.09 1 220164 4502000 4WELL 1 - 1696 Taylor - ----11/10/2014 ------------<0.09 ------WELL 1 - 1696 Taylor - ---0.512/9/2014 -------------------WELL 1 - 1696 Taylor - ----7/8/2015 ------------<0.09 ------WELL 1 - 1696 Taylor - 0.2 9 320-8/9/2016 1900 1260 -1089 43 267 4 213 328 220180 0.5 1 280171 1302400 5WELL 1 - 1696 Taylor - ----12/29/2017 ----- - - --- --0.4 ------WELL 1 - 1696 Taylor - ----8/21/2018 ----- - - --- --0.4 ------WELL 1 - 1696 Taylor - ----7/22/2019 ---<50- - - --- ---<10 -186 --10WELL 1 - 1696 Taylor - --<50-11/21/2019 -1430 --122 69 239 4 209 - --<0.4 -240-5202000 -WELL 1 - 1696 Taylor - ----12/5/2001 ----- - 252 --- ---------WELL 2 - 1398 Taylor - ----12/4/2002 ----- - 232 --- ---------WELL 2 - 1398 Taylor - ----6/11/2003 ----- - 209 --- ---------WELL 2 - 1398 Taylor - ----8/6/2003 ----- - - --- --<0.09 ------WELL 2 - 1398 Taylor - 0.2 2 20-7/21/2004 1160 730 -1054 28 149 3 145 149 290240 <0.09 1 14083.1 2002000 2WELL 2 - 1398 Taylor - ----12/17/2004 ----- - 257 --- ---------WELL 2 - 1398 Taylor - ----5/18/2005 ----- - 248 --- ---------WELL 2 - 1398 Taylor - -2 --6/22/2005 ----- - - --- ---------WELL 2 - 1398 Taylor - ----7/27/2005 ----- - - --- --<0.09 ------WELL 2 - 1398 Taylor - -2 --8/17/2005 ----- - - --- ---------WELL 2 - 1398 Taylor - ----7/19/2006 ----- - - --- --0.1 ------WELL 2 - 1398 Taylor - 0.1 2 20-7/5/2007 1510 920 -1070 35 188 3 170 278 260220 <0.09 1 13095.8 2701830 2WELL 2 - 1398 Taylor - ----7/3/2008 ----- - - --- --<0.09 ------WELL 2 - 1398 Taylor - ----7/17/2009 ----- - - --- --<0.09 ------WELL 2 - 1398 Taylor - 0.1 3 20-7/20/2010 1600 980 -1080 40 202 4 166 298 250200 <0.09 1 180133 3102000 4WELL 2 - 1398 Taylor - ----7/20/2011 ----- - - --- --<0.09 ------WELL 2 - 1398 Taylor - ----7/26/2012 ----- - - --- --<0.09 ------WELL 2 - 1398 Taylor - 0.1 2 20-8/13/2013 1640 970 -1078 40 201 4 198 365 250210 <0.09 2 120117 3001800 3WELL 2 - 1398 Taylor - Thursday, September 10, 2020Page 35 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer ANGLERS SUBDIVISION 4 ----8/12/2014 ------------<0.09 ------WELL 2 - 1398 Taylor - ---0.059/9/2014 -------------------WELL 2 - 1398 Taylor - ----7/8/2015 ------------<0.09 ------WELL 2 - 1398 Taylor - 0.1 3 20-8/9/2016 1760 1100 -10894520541543122301900.1 1 150137 3501900 5WELL 2 - 1398 Taylor - ----12/29/2017 ------------0.4 ------WELL 2 - 1398 Taylor - ----8/21/2018 ------------0.4 ------WELL 2 - 1398 Taylor - -4 --7/22/2019 ---<50---------<10 -159 --7WELL 2 - 1398 Taylor - 0.1 -80-11/21/2019 ----92 52 209 3 182 364 --<0.4 -760-3602000 -WELL 2 - 1398 Taylor - ----11/7/2001 ------241 ------------WELL 3 - 1698 Taylor - ----5/8/2002 ------245 ------------WELL 3 - 1698 Taylor - ----5/7/2003 ------264 ------------WELL 3 - 1698 Taylor - 0.2 10 20-7/21/2004 2220 1340 -10115572544204508240200<0.09 1 15096.3 2902200 5WELL 3 - 1698 Taylor - -10 --6/22/2005 -------------------WELL 3 - 1698 Taylor - ----7/27/2005 ------------<0.09 ------WELL 3 - 1698 Taylor - -9 --8/17/2005 ----- - - --- ---------WELL 3 - 1698 Taylor - ----7/19/2006 ----- - - --- --<0.09 ------WELL 3 - 1698 Taylor - ----5/23/2007 ----- - 191 --- ---------WELL 3 - 1698 Taylor - 0.1 6 20-7/5/2007 1840 1120 -1087 43 224 4 189 385 250200 0.1 1 10087.1 2401880 4WELL 3 - 1698 Taylor - ----7/17/2009 ----- - - --- --0.1 ------WELL 3 - 1698 Taylor - 0.2 3 20-7/20/2010 1620 980 -1081 40 205 4 167 305 250200 0.2 1 100124 2402000 5WELL 3 - 1698 Taylor - ----7/26/2012 ----- - - --- --0.2 ------WELL 3 - 1698 Taylor - 0.1 10 20-7/9/2013 2180 1320 -10102 50 272 3 230 490 240190 0.5 1 28093.6 2602200 3WELL 3 - 1698 Taylor - ----8/12/2014 ----- - - --- --<0.09 ------WELL 3 - 1698 Taylor - ---0.059/9/2014 ----- - - --- ---------WELL 3 - 1698 Taylor - ----7/8/2015 ----- - - --- --<0.09 ------WELL 3 - 1698 Taylor - 0.2 4 20-8/9/2016 2040 1200 -10111 58 233 4 169 384 190160 0.1 1 3400.2 3402000 6WELL 3 - 1698 Taylor - ----12/29/2017 ----- - - --- --0.4 ------WELL 3 - 1698 Taylor - ----8/21/2018 ----- - - --- --0.4 ------WELL 3 - 1698 Taylor - -6 --7/22/2019 ---<50- - - --- -----138 ---WELL 3 - 1698 Taylor - 0.1 -<50-11/21/2019 ----- 71 248 4 207 520 --<0.4 -<100-2202100 -WELL 3 - 1698 Taylor - BAY STANDARDS 0.4 2 20-6/23/2004 1430 870 -10109 46 128 2 147 193 390320 4.83 4 6067.5 103100 3Well Head - ----6/1/2005 ----- - - --- --4.79 ------Well Head - ----6/6/2008 ----- - - --- --4.04 ------Well Head - ----6/4/2009 ----- - - --- --5.4 ------Well Head - 0.4 2 20-6/1/2010 1420 870 -10107 45 143 2 141 183 380310 -3 12061.7 103300 3Well Head - Thursday, September 10, 2020Page 36 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer BAY STANDARDS ----6/14/2011 ------------4.99 ------Well Head - ----6/5/2012 ------------5.22 ------Well Head - 0.2 2 20-6/4/2013 1420 870 -10974113631301693803105.04 7 5060.8 103100 3Well Head - ----6/10/2014 ------------5.26 ------Well Head - ---1.512/8/2014 -------------------Well Head - ----6/2/2015 ------------5.33 ------Well Head - ----6/6/2016 ------------5.4 ------Well Head - ----6/29/2016 ------------5.8 ------Well Head - ----6/1/2017 ------------5.6 ------Well Head - ----6/4/2018 ------------5.4 ------Well Head - BETHEL BAPTIST CHURCH ----11/19/2001 ------------ND ------Well Head - ----11/22/2002 ------------ND ------Well Head - ----11/18/2003 ----- - - --- --ND ------Well Head - ND <2 50-8/24/2004 1400 830 -<5036 22 240 2.9 160 220 260220 ND <10 100141 190-<5Well Head - ----11/17/2004 ----- - - --- --ND ------Well Head - ----11/27/2006 ----- - - --- --ND ------Well Head - ----11/15/2007 ----- - - --- --ND ------Well Head - ----11/13/2008 ----- - - --- --ND ------Well Head - ----11/16/2009 ----- - - --- --ND ------Well Head - ----11/10/2010 ----- - - --- --ND ------Well Head - ----11/9/2011 ----- - - --- --ND ------Well Head - ----11/12/2012 ----- - - --- --ND ------Well Head - ----12/9/2013 ----- - - --- --ND ------Well Head - ----12/10/2014 ----- - - --- --ND ------Well Head - ----12/15/2015 ----- - - --- --ND ------Well Head - ----12/7/2016 ----- - - --- --ND ------Well Head - ----12/5/2017 ----- - - --- --ND ------Well Head - ----12/4/2018 ----- - - --- --ND ------Well Head - ----12/4/2019 ----- - - --- --ND ------Well Head - BETHEL HARBOR ----1/23/2003 ----- - - --- --ND ------WELL - ----1/26/2004 ----- - - --- --ND ------WELL - ----1/20/2005 ----- - - --- --ND ------WELL - ----1/25/2006 ----- - - --- --ND ------WELL - Thursday, September 10, 2020Page 37 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer BETHEL HARBOR ----1/24/2007 ------------ND ------WELL - ----1/10/2008 ------------ND ------WELL - ----1/12/2009 ------------ND ------WELL - ----1/20/2011 ------------ND ------WELL - ----1/23/2012 ------------ND ------WELL - ----1/28/2013 ------------ND ------WELL - ----1/20/2014 ------------ND ------WELL - ----1/21/2015 ------------ND ------WELL - ----1/13/2016 ------------ND ------WELL - ----1/17/2017 ------------ND ------WELL - ----1/17/2018 ------------ND ------WELL - ----1/9/2019 ------------ND ------WELL - BETHEL ISLAND GOLF & RESORT ----11/30/2001 ----- - - --- --0.5 ------WELLHEAD - ----11/26/2002 ----- - - --- --ND ------WELLHEAD - ----11/19/2003 ----- - - --- --0.5 ------WELLHEAD - ----11/17/2004 ----- - - --- --ND ------WELLHEAD - ----12/12/2018 ----- - - --- --0.85 ------WELLHEAD - BETHEL ISLAND MUTUAL WATER CO ----12/27/2001 ----- - - --- --ND ------WELL 1 - 0.3 7 50-11/19/2003 1100 730 -<5023 11 240 2 120 160 330270 ND <10 <100<100 120-<5WELL 1 - ----12/19/2003 ----- - - --- --ND ------WELL 1 - 0.2 9.6 180ND7/27/2016 1200 730 -<5021 10 220 2 110 150 330270 ND <10 <100100 80-<5WELL 1 - ----8/30/2017 ----- - - --- --ND ------WELL 1 - ----11/30/2018 ----- - - --- --ND ------WELL 1 - -9 <50-7/31/2019 -780 -ND21 11 240 2.2 -150 --ND ND NDND 96-NDWELL 1 - BETHEL MARKET ----6/23/2004 ----- - - --- --ND ------WELLHEAD - ----6/23/2005 ----- - - --- --ND ------WELLHEAD - ----6/22/2006 ----- - - --- --ND ------WELLHEAD - ----6/29/2007 ----- - - --- --ND ------WELLHEAD - ----6/19/2008 ----- - - --- --ND ------WELLHEAD - ----6/15/2009 ----- - - --- --ND ------WELLHEAD - ----6/14/2010 ----- - - --- --ND ------WELLHEAD - Thursday, September 10, 2020Page 38 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer BETHEL MARKET ----6/8/2011 ------------ND ------WELLHEAD - ----6/11/2012 ------------ND ------WELLHEAD - ----6/5/2013 ------------ND ------WELLHEAD - ----6/11/2014 ------------ND ------WELLHEAD - ----6/4/2015 ------------ND ------WELLHEAD - ----6/6/2016 ------------ND ------WELLHEAD - ----6/26/2017 ------------ND ------WELLHEAD - ----6/26/2018 ------------ND ------WELLHEAD - BETHEL MISSIONARY BAPTIST ----10/4/2001 ------------21 ------Well Head - ----8/6/2002 ------------2 ------Well Head - ----10/3/2002 ------------10 ------Well Head - ----10/2/2003 ------------11 ------Well Head - 0.3 <2 50-6/30/2004 1800 1100 -<50130 62 160 3.9 220 280 350290 12 <10 100<100 20-<5Well Head - ----10/4/2004 ----- - - --- --11 ------Well Head - ----10/3/2005 ----- - - --- --7.5 ------Well Head - ----10/2/2006 ----- - - --- --4.5 ------Well Head - ----10/1/2007 ----- - - --- --13 ------Well Head - ----10/1/2008 ----- - - --- --14 ------Well Head - ----10/4/2010 ----- - - --- --4.1 ------Well Head - ----10/3/2011 ----- - - --- --4.3 ------Well Head - ----10/1/2012 ----- - - --- --3.4 ------Well Head - ---112/9/2014 ----- - - --- ---------Well Head - 0.21 <2 -ND11/21/2017 ----- - - --- --1.9 <10 -<100 --<5Well Head - ----7/17/2018 ----- - - --- --8.6 ------Well Head - ----10/1/2018 ----- - - --- --5.1 ------Well Head - BIG OAK MOBILE HOME PARK WATER 0.4 4 20-6/23/2004 1470 950 -10105 50 145 5 251 154 320260 -1 5058.3 110800 7Well Head - West well - ----6/8/2005 ----- - - --- --9.47 ------Well Head - West well - ----6/14/2006 ----- - - --- --6.84 ------Well Head - West well - 0.3 4 20-6/15/2007 1660 1120 -10120 55 171 5 300 169 320280 6.03 1 5053.2 150550 6Well Head - West well - 0.2 4.5 50-8/9/2011 1600 1000 -50110 50 160 4.1 280 160 320260 8.6 1 100100 110-<5Well Head - West well - 0.24 3.5 <50ND7/27/2016 1600 --50110 52 140 4.3 300 170 320270 8.8 <10 <100<100 93-<5Well Head - West well - ----9/12/2017 ----- - - --- --9.6 ------Well Head - West well - ----9/10/2018 ----- - - --- --8.9 ------Well Head - West well - Thursday, September 10, 2020Page 39 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer BIG OAK MOBILE HOME PARK WATER -4 ND-8/14/2019 -1200 -20130561405.1 310 180 --8.7 ND NDND 110-5.6Well Head - West well - 0.4 4 20-6/23/2004 1330 850 -10914413541891493202607.07 1 5064.4 130800 6Wellhead- East well - ----6/8/2005 ------------7.55 ------Wellhead- East well - ----6/14/2006 ------------6.6 ------Wellhead- East well - 0.3 4 20-6/15/2007 1340 850 -10843914541971303102506.28 1 5057.4 130580 5Wellhead- East well - ----6/6/2008 ------------1.7 ------Wellhead- East well - 0.2 4 <50-8/9/2011 1400 890 -5088391403.9 210 140 290240 9.5 1 100100 130-<5Wellhead- East well - 0.3 2.9 50ND7/27/2016 1500 1000 -5098461304.3 260 140 320260 9.5 <10 <100100 150-<5Wellhead- East well - ----8/30/2017 ------------9.6 ------Wellhead- East well - ----9/10/2018 ------------9.8 ------Wellhead- East well - 0.2 4 ND-8/14/2019 -990 --94 -130 4.4 250 ---8.7 ND -<100 150-6Wellhead- East well - BLUE TIP TRAILER PARK WATER ----2/4/2008 ------------0.63 ------WELL HEAD - ----8/29/2018 ----- - - --- --1.2 ------WELL HEAD - BON GUSTOS ----8/25/2016 ----- - - --- --ND ------TREATMENT - ----8/10/2017 ----- - - --- --ND ------TREATMENT - ----11/15/2017 ----- - - --- --ND ------TREATMENT - ----5/8/2018 ----- - - --- --ND ------TREATMENT - ----3/1/2019 ----- - - --- --2 ------TREATMENT - ----11/19/2019 ----- - - --- --ND ------TREATMENT - ----8/31/2004 ----- - - --- --15 ------Well Head - ----8/31/2005 ----- - - --- --15 ------Well Head - ----8/31/2006 ----- - - --- --14 ------Well Head - ----8/30/2007 ----- - - --- --16 ------Well Head - ----12/28/2007 ----- - - --- --17 ------Well Head - ----9/17/2008 ----- - - --- --12 ------Well Head - ----10/9/2008 ----- - - --- --11 ------Well Head - ----8/31/2009 ----- - - --- --8.8 ------Well Head - ----8/26/2010 ----- - - --- --14 ------Well Head - ----8/30/2011 ----- - - --- --14 ------Well Head - ----2/21/2018 ----- - - --- --ND ------Well Head - ----8/29/2018 ----- - - --- --2.3 ------Well Head - ----11/14/2018 ----- - - --- --18 ------Well Head - ----2/20/2019 ----- - - --- --14 ------Well Head - Thursday, September 10, 2020Page 40 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer BON GUSTOS 0.44 2.02 75-4/25/2019 -650 -29551251502.88 110 202 --ND ND 386160 212-NDWell Head - BRENTWOOD CREEK FARM 0.2 <2 50-8/17/2004 960 --<5049231301.7 84 91 340280 -<10 140<100 190-<5WELL 2 - CAMP 1 - 0.2 <2 50-8/17/2004 1000 --<5028151801.6 51 88 430350 -<10 100<100 140-<5WELL 3 - CAMP 2 - BRENTWOOD MISSIONARY BAPTIST ----6/3/2002 ------------9.5 ------Well Head - ----6/2/2003 ------------8.4 ------Well Head - ----6/3/2004 ------------8.8 ------Well Head - 1.2 <2 50-6/30/2004 1300 770 -<50100461203.4 130 150 370310 0.95 <10 100<100 <20-<5Well Head - ----6/2/2005 ------------8.4 ------Well Head - ----6/5/2006 ------------7.5 ------Well Head - 0.3 2.4 <50-7/11/2007 1200 --5081311101.5 97 150 310250 7 10 <100100 <20-<5Well Head - ----6/2/2008 ----- - - --- --7.5 ------Well Head - ----6/1/2009 ----- - - --- --6.6 ------Well Head - ----9/7/2010 ----- - - --- --4.7 ------Well Head - ----7/2/2012 ----- - - --- --8.1 ------Well Head - ----7/8/2013 ----- - - --- --7.5 ------Well Head - ----7/7/2014 ----- - - --- --7.2 ------Well Head - ----7/7/2015 ----- - - --- --7.5 ------Well Head - ----7/5/2016 ----- - - --- --7.8 ------Well Head - ----7/10/2017 ----- - - --- --9.1 ------Well Head - ----7/9/2019 ----- - - --- --8.7 ------Well Head - BRIDGEHEAD CAFE ----11/13/2001 ----- - - --- --4.3 ------Well Head - ----2/12/2002 ----- - - --- --6.3 ------Well Head - ----8/13/2002 ----- - - --- --9.9 ------Well Head - ----9/10/2002 ----- - - --- --4.7 ------Well Head - ----11/19/2002 ----- - - --- --5.2 ------Well Head - ----2/11/2003 ----- - - --- --5.4 ------Well Head - ----5/20/2003 ----- - - --- --2.9 ------Well Head - ----8/18/2003 ----- - - --- --4.7 ------Well Head - ----11/11/2003 ----- - - --- --5.2 ------Well Head - ----2/10/2004 ----- - - --- --5.6 ------Well Head - ----5/12/2004 ----- - - --- --5.4 ------Well Head - Thursday, September 10, 2020Page 41 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer BRIDGEHEAD CAFE BYRON AIRPORT ----5/7/2002 ------------ND ------Well Head - ----5/6/2003 ------------ND ------Well Head - ----5/4/2004 ------------ND ------Well Head - ----5/5/2005 ------------ND ------Well Head - ----5/3/2006 ------------ND ------Well Head - ----5/8/2008 ------------ND ------Well Head - ----5/5/2009 ------------ND ------Well Head - ----5/12/2010 ------------<0.5 ------Well Head - ----5/12/2011 ------------ND ------Well Head - ----5/7/2012 ------------ND ------Well Head - ----5/9/2013 ------------ND ------Well Head - ----5/7/2014 ------------ND ------Well Head - ----5/21/2015 ----- - - --- --ND ------Well Head - ----5/31/2016 ----- - - --- --ND ------Well Head - ----5/25/2017 ----- - - --- --ND ------Well Head - ----11/14/2018 ----- - - --- --ND ------Well Head - ----11/19/2019 ----- - - --- --ND ------Well Head - BYRON CORNERS INC ----8/4/2004 ----- - - --- --18 ------Well Head - ----8/3/2005 ----- - - --- --22.6 ------Well Head - ----6/30/2006 ----- - - --- --22.6 ------Well Head - ----8/3/2006 ----- - - --- --21 ------Well Head - ----11/30/2006 ----- - - --- --1.5 ------Well Head - ----9/28/2007 ----- - - --- --17 ------Well Head - ----9/23/2008 ----- - - --- --16 ------Well Head - ----2/26/2009 ----- - - --- --2.3 ------Well Head - ----5/28/2009 ----- - - --- --4.3 ------Well Head - ----8/31/2009 ----- - - --- --8.8 ------Well Head - ----11/30/2009 ----- - - --- --12 ------Well Head - ----2/25/2010 ----- - - --- --2 ------Well Head - ----5/25/2010 ----- - - --- --3.4 ------Well Head - ----8/26/2010 ----- - - --- --2 ------Well Head - ----11/13/2010 ----- - - --- --11 ------Well Head - ----2/28/2011 ----- - - --- --1 ------Well Head - Thursday, September 10, 2020Page 42 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer BYRON CORNERS INC ----5/31/2011 ------------2 ------Well Head - ----8/30/2011 ------------1.9 ------Well Head - ----11/30/2011 ------------2.1 ------Well Head - ----2/28/2012 ------------2 ------Well Head - ----5/30/2012 ------------2.3 ------Well Head - ----8/29/2012 ------------2 ------Well Head - ----2/28/2013 ------------2.3 ------Well Head - ----5/30/2013 ------------2.5 ------Well Head - ----8/27/2013 ------------2.9 ------Well Head - ----11/21/2013 ------------2 ------Well Head - ----2/19/2014 ------------2.5 ------Well Head - ----5/14/2014 ------------2.3 ------Well Head - ----8/18/2014 ------------2 ------Well Head - ----11/13/2014 ------------2 ------Well Head - ----2/11/2015 ----- - - --- --2.1 ------Well Head - ----6/17/2015 ----- - - --- --2.5 ------Well Head - ----8/11/2015 ----- - - --- --2.3 ------Well Head - ----11/11/2015 ----- - - --- --ND ------Well Head - ----2/10/2016 ----- - - --- --ND ------Well Head - ----5/24/2016 ----- - - --- --ND ------Well Head - ----8/22/2016 ----- - - --- --ND ------Well Head - ----11/16/2016 ----- - - --- --ND ------Well Head - ----2/28/2017 ----- - - --- --0.03 ------Well Head - ----5/25/2017 ----- - - --- --ND ------Well Head - ----8/10/2017 ----- - - --- --ND ------Well Head - ----5/8/2018 ----- - - --- --ND ------Well Head - ----8/29/2018 ----- - - --- --ND ------Well Head - ----11/14/2018 ----- - - --- --9.4 ------Well Head - ----2/20/2019 ----- - - --- --9.7 ------Well Head - ----5/1/2019 ----- - - --- --10 ------Well Head - ----8/14/2019 ----- - - --- --9.6 ------Well Head - ----11/19/2019 ----- - - --- --10 ------Well Head - BYRON INN ----2/7/2002 ----- - - --- --2.3 ------Well Head - ----2/13/2003 ----- - - --- --2.5 ------Well Head - ----2/6/2006 ----- - - --- --2.7 ------Well Head - ----2/14/2008 ----- - - --- --1.7 ------Well Head - Thursday, September 10, 2020Page 43 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer BYRON INN ----2/10/2010 ------------1.6 ------Well Head - ----2/17/2011 ------------2 ------Well Head - ----2/13/2013 ------------1.4 ------Well Head - ----2/10/2014 ------------1.9 ------Well Head - ----2/5/2015 ------------1.5 ------Well Head - ----2/17/2016 ------------2.6 ------Well Head - ----3/2/2017 ------------3 ------Well Head - ----11/16/2018 ------------3.9 ------Well Head - ----11/21/2019 ------------1.7 ------Well Head - BYRON UNITED METHODIST ----3/19/2007 ------------0.54 ------WELL HEAD - ----3/25/2008 ------------0.7 ------WELL HEAD - ----3/5/2009 ------------0.59 ------WELL HEAD - 0.4 2.9 --10/15/2009 ---50- - - --- --0.56 18 -100 --<5WELL HEAD - ----4/1/2010 ----- - - --- --0.66 ------WELL HEAD - ----4/7/2010 ----- - - --- --<0.5 ------WELL HEAD - ----4/6/2011 ----- - - --- --0.5 ------WELL HEAD - ----4/8/2013 ----- - - --- --0.63 ------WELL HEAD - ----4/6/2016 ----- - - --- --0.72 ------WELL HEAD - ----4/10/2017 ----- - - --- --0.76 ------WELL HEAD - ----4/23/2018 ----- - - --- --0.9 ------WELL HEAD - ----4/8/2019 ----- - - --- --1 ------WELL HEAD - CALIENTE ISLE WATER SYSTEM ----8/20/2004 ----- - - --- --ND ------WELLHEAD - ----8/24/2005 ----- - - --- --ND ------WELLHEAD - CAMINO MOBILEHOME ----3/3/2004 ----- - - --- --<0.09 ------WELL - 0.1 2 60-3/22/2006 1140 730 -1020 10 201 1 115 103 360310 <0.09 1 15052.2 1102500 2WELL- ----3/7/2007 ----- - - --- --<0.09 ------WELL - ----3/5/2008 ----- - - --- --<0.09 ------WELL - 0.1 -<50-10/15/2009 1100 720 --22 11 220 1.2 110 100 390320 ND -500-110--WELL - 0.2 2 50-8/9/2011 1200 680 -50229.6 210 1.3 110 100 370300 ND 1 150100 110-<5WELL- 0.3 2 50ND7/27/2016 1100 710 -50219.6 210 1.3 110 99 370300 ND <10 130<100 110-<5WELL- ----9/10/2018 ----- - - --- --ND ------WELL - Thursday, September 10, 2020Page 44 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer CAMINO MOBILEHOME 0.19 2.4 <50-9/18/2019 -750 -ND219.46 220 1.4 110 100 ---ND 200ND ---WELL - CARSON SWIM SCHOOL ----4/14/2004 ------------14.1 ------WELL HEAD - ----4/13/2005 ------------16 ------WELL HEAD - ----4/20/2007 ------------18 ------WELL HEAD - CASA DEL RIO WATER SYSTEM ----10/17/2001 ------------ND ------Well Head - ----10/15/2002 ------------ND ------Well Head - ----10/20/2003 ------------ND ------Well Head - ----10/20/2004 ------------ND ------Well Head - ----10/19/2005 ------------ND ------Well Head - CECCHINI WATER ----6/29/2004 ----- - - --- --ND ------WELL - ----7/28/2004 ----- - - --- --ND ------WELL - ----8/30/2017 ----- - - --- --ND ------WELL - ----8/30/2017 ----- - - --- --0.4 ------WELL 2 - CHURCH OF JESUS CHRIST 0.7 <2 50-7/15/2004 3100 --<50160 78 370 8.7 990 250 250200 -<10 140<100 34-<5Well Head - 0.9 2.4 <50-7/11/2007 3000 --50170 74 360 8.7 1000 260 260210 -10 220100 39-5Well Head - COLONIA SANTA MARIA 0.3 <2 50-4/22/2002 1300 800 -<5090 37 150 2.2 120 170 -320 5.6 <10 100<100 <20-<5Well Head - ----11/25/2003 ----- - - --- --ND ------Well Head - ----11/2/2004 ----- - - --- --5 ------Well Head - ----11/1/2005 ----- - - --- --4.7 ------Well Head - 0.4 2 50-10/18/2006 1300 --<5075 33 150 2 120 160 380310 -5.1 10042 <20-5Well Head - ----11/1/2006 ----- - - --- --5 ------Well Head - ----11/1/2007 ----- - - --- --5 ------Well Head - ----11/3/2008 ----- - - --- --5 ------Well Head - ----11/2/2009 ----- - - --- --5 ------Well Head - ----11/1/2010 ----- - - --- --5.2 ------Well Head - ----11/2/2011 ----- - - --- --5.4 ------Well Head - Thursday, September 10, 2020Page 45 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer COLONIA SANTA MARIA ----11/1/2012 ------------5.4 ------Well Head - ----11/3/2014 ------------5.6 ------Well Head - ----12/1/2014 ------------6.1 ------Well Head - ----11/2/2015 ------------5.6 ------Well Head - ----11/2/2016 ------------5.7 ------Well Head - 0.24 <2 -4.68/2/2017 ---<50--------6.1 10 -<100 --<5Well Head - ----11/6/2017 ------------5.9 ------Well Head - ----11/12/2018 ------------6.1 ------Well Head - CRUISER HAVEN MARINA ----12/28/2001 ------------ND ------Well Head - ----12/31/2002 ------------ND ------Well Head - ----12/31/2003 ------------ND ------Well Head - ----12/29/2004 ------------ND ------Well Head - ----12/27/2005 ----- - - --- --ND ------Well Head - ----9/19/2007 ----- - - --- --ND ------Well Head - ----9/17/2008 ----- - - --- --ND ------Well Head - ----9/22/2009 ----- - - --- --ND ------Well Head - ----9/20/2010 ----- - - --- --<0.2 ------Well Head - ----12/2/2010 ----- - - --- --<0.2 ------Well Head - ----9/26/2011 ----- - - --- --<0.2 ------Well Head - ----10/30/2018 ----- - - --- --ND ------Well Head - ----9/16/2019 ----- - - --- --ND ------Well Head - D ANNA YACHT CENTER ----7/25/2005 ----- - - --- --ND ------Well Head - ----9/28/2005 ----- - - --- --<0.5 ------Well Head - ----7/30/2007 ----- - - --- --<0.5 ------Well Head - ----9/24/2007 ----- - - --- --ND ------Well Head - ----7/24/2008 ----- - - --- --0.5 ------Well Head - ----9/30/2009 ----- - - --- --<0.5 ------Well Head - DAVIS CAMP *CL 10/08 ----10/18/2001 ----- - - --- --3.6 ------east well (south)- 0.3 5 50-10/23/2001 1900 --<50180 69 210 3.3 370 290 -410 3.6 <10 100<100 20-<5east well (south)- ----1/24/2002 ----- - - --- --3.8 ------east well (south)- ----7/18/2002 ----- - - --- --3.8 ------east well (south)- Thursday, September 10, 2020Page 46 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer DAVIS CAMP *CL 10/08 ----1/27/2003 ------------2.9 ------east well (south)- ----4/24/2003 ------------3.6 ------east well (south)- ----7/17/2003 ------------6.1 ------east well (south)- ----10/21/2003 ------------8.1 ------east well (south)- ----1/27/2004 ------------3.2 ------east well (south)- ----4/22/2004 ------------3.8 ------east well (south)- 0.2 <2 50-7/15/2004 2400 1500 -<50170742202.3 410 320 470380 4.1 <10 100<100 20-<5east well (south)- ----1/28/2005 ------------3.6 ------east well (south)- ----4/20/2005 ------------4.1 ------east well (south)- ----7/25/2005 ------------3.8 ------east well (south)- ----10/19/2005 ------------3.4 ------east well (south)- ----10/18/2001 ------------11 ------west well (north)- 0.3 5 50-10/23/2001 1700 --<50170671402.5 240 220 -330 11 <10 <100<100 <20-<5west well (north)- ----7/18/2002 ------------8.4 ------west well (north)- ----10/14/2002 ----- - - --- --7.5 ------west well (north)- ----7/17/2003 ----- - - --- --9.9 ------west well (north)- ----10/21/2003 ----- - - --- --8.1 ------west well (north)- ----4/22/2004 ----- - - --- --9.3 ------west well (north)- ----7/29/2004 ----- - - --- --7.7 ------west well (north)- 0.2 <2 50-8/18/2004 1600 1000 -<50140 53 140 1.4 230 220 400320 7.2 <10 100<100 20-<5west well (north)- ----4/20/2005 ----- - - --- --1.6 ------west well (north)- ----7/25/2005 ----- - - --- --6.1 ------west well (north)- ----10/19/2005 ----- - - --- --6.6 ------west well (north)- DELTA KIDS CENTER *CL 2/07 ----6/11/2002 ----- - - --- --1.5 ------Well Head - ----6/20/2003 ----- - - --- --1.7 ------Well Head - 0.4 <2 --9/30/2003 ---<50- - - --- --1.5 --<100 --<5Well Head - ----6/2/2004 ----- - - --- --1.5 ------Well Head - ----6/6/2005 ----- - - --- --1.3 ------Well Head - ----6/5/2006 ----- - - --- --2 ------Well Head - DELTA MUTUAL WATER COMPANY 0.2 10 <50-11/12/2003 1500 870 -<5040 21 250 2.6 140 230 320270 ND <10 <100<100 220-<5East Well - ----11/16/2004 ----- - - --- --ND ------East Well - 0.1 8.7 50-11/8/2006 1500 880 -5041 24 260 2.7 150 250 320260 ND 10 100100 230-5East Well - ----11/19/2008 ----- - - --- --ND ------East Well - Thursday, September 10, 2020Page 47 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer DELTA MUTUAL WATER COMPANY 0.2 11 50-11/18/2009 1500 950 -5041232502.7 140 250 330270 ND 3.1 100100 260-<5East Well - -9 --1/20/2010 -------------------East Well - -8.7 --4/22/2010 -------------------East Well - -9 --7/19/2010 -------------------East Well - -9 --10/18/2010 -------------------East Well - -10 --1/12/2011 -------------------East Well - -10 --4/14/2011 -------------------East Well - -11 --7/20/2011 -------------------East Well - -11 --10/19/2011 -------------------East Well - -6.5 --1/11/2012 -------------------East Well - -8.9 --4/9/2012 -------------------East Well - -10 --7/16/2012 -------------------East Well - -9.4 --10/31/2012 -------------------East Well - 0.3 9.8 <50-11/14/2012 1500 940 --42 25 270 2.9 160 270 320260 ND 1 <100100 260-<5East Well - -6.8 --1/24/2013 ----- - - --- ---------East Well - -10 --4/30/2013 ----- - - --- ---------East Well - -8.4 --7/24/2013 ----- - - --- ---------East Well - -9.2 --10/9/2013 ----- - - --- ---------East Well - -8.3 --1/30/2014 ----- - - --- ---------East Well - -8.6 --4/28/2014 ----- - - --- ---------East Well - ---ND8/14/2014 ----- - - --- ---------East Well - -9 --11/3/2014 ----- - - --- ---------East Well - -9 --1/26/2015 ----- - - --- ---------East Well - -9.1 --4/15/2015 ----- - - --- ---------East Well - -9.8 --7/30/2015 ----- - - --- ---------East Well - -9.6 --10/28/2015 ----- - - --- ---------East Well - -8.1 --1/28/2016 ----- - - --- ---------East Well - -9.1 --4/11/2016 ----- - - --- ---------East Well - ND 8.9 <50-5/26/2016 1600 970 -<5041 23 260 2.6 160 270 320260 ND <10 <100100 240-<5East Well - -9.5 --7/29/2016 ----- - - --- ---------East Well - -8.4 --10/24/2016 ----- - - --- ---------East Well - -10.6 --2/1/2017 ----- - - --- ---------East Well - -10 --4/24/2017 ----- - - --- ---------East Well - -12 --10/31/2017 ----- - - --- ---------East Well - -11 --1/31/2018 ----- - - --- ---------East Well - -10 --5/2/2018 ----- - - --- ---------East Well - -11 --8/1/2018 ----- - - --- ---------East Well - -11 --10/24/2018 ----- - - --- ---------East Well - Thursday, September 10, 2020Page 48 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer DELTA MUTUAL WATER COMPANY ----10/29/2018 ------------ND ------East Well - ----11/26/2018 ------------ND ------East Well - -<2 <50-4/8/2019 -870 --46 25 262 3 149 257 ---<10 <100169 <203600 <5East Well - -10 --7/29/2019 -------------------East Well - -10 --10/14/2019 -------------------East Well - ----3/21/2002 ------------ND ------West Well - 0.2 11 <50-11/12/2003 1200 690 -<5029162102.3 110 150 330270 ND <10 <100<100 160-<5West Well - 0.2 9.3 50-11/8/2006 1200 740 -5036212402.6 120 170 330270 ND 10 100100 190-5West Well - ----11/14/2006 ------------ND ------West Well - 0.2 10 50-11/18/2009 1300 720 -5029172102.4 120 170 340280 ND 6.6 100100 180-<5West Well - ----11/24/2009 ------------2.1 ------West Well - -8.8 --2/17/2010 -------------------West Well - -7.8 --5/19/2010 -------------------West Well - -11 --8/18/2010 -------------------West Well - -10 --2/9/2011 ----- - - --- ---------West Well - -8.7 --5/19/2011 ----- - - --- ---------West Well - -10 --8/18/2011 ----- - - --- ---------West Well - -9.3 --2/8/2012 ----- - - --- ---------West Well - -11 --5/17/2012 ----- - - --- ---------West Well - -8.9 --8/14/2012 ----- - - --- ---------West Well - 0.2 10.5 <50-11/14/2012 1300 760 --31 17 230 2.5 130 180 330270 ND 1 <100100 180-<5West Well - -9.9 --11/30/2012 ----- - - --- --ND ------West Well - -9.6 --2/21/2013 ----- - - --- ---------West Well - -<2 --5/23/2013 ----- - - --- ---------West Well - -10 --8/19/2013 ----- - - --- ---------West Well - -10 --11/11/2013 ----- - - --- --ND ------West Well - -9 --2/24/2014 ----- - - --- ---------West Well - -7.2 --5/21/2014 ----- - - --- ---------West Well - -8.8 -ND8/14/2014 ----- - - --- ---------West Well - -9.3 --11/20/2014 ----- - - --- ---------West Well - -11 --2/18/2015 ----- - - --- ---------West Well - -8.7 --5/28/2015 ----- - - --- ---------West Well - -11 --8/25/2015 ----- - - --- ---------West Well - -9.8 --11/30/2015 ----- - - --- ---------West Well - -9 --2/17/2016 ----- - - --- ---------West Well - -10 --5/16/2016 ----- - - --- ---------West Well - ND 8.5 <50-5/26/2016 1600 960 -<5041 23 270 2.6 150 270 320260 ND <10 <100100 230-<5West Well - Thursday, September 10, 2020Page 49 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer DELTA MUTUAL WATER COMPANY -9.5 --8/30/2016 -------------------West Well - -9 --11/22/2016 ------------ND ------West Well - -7.7 --2/23/2017 -------------------West Well - -12 --5/17/2017 -------------------West Well - -9.7 --7/31/2017 -------------------West Well - -10.6 --8/16/2017 -------------------West Well - -11 --11/27/2017 -------------------West Well - -11 --2/21/2018 -------------------West Well - -7.5 --5/31/2018 -------------------West Well - -13 --8/30/2018 -------------------West Well - -12 --11/26/2018 ------------ND ------West Well - 0.1 12 <50-4/8/2019 -710 -<5027161823121---<0.4 <10 <100<100 1602900 <5West Well - -15 --7/29/2019 -------------------West Well - -10 --10/14/2019 -------------------West Well - DELTA SPORTSMAN ----11/7/2001 ----- - - --- --<0.09 ------Well Head - ----11/16/2005 ----- - - --- --<0.09 ------Well Head - ----11/3/2008 ----- - - --- --ND ------Well Head - ----11/30/2009 ----- - - --- --ND ------Well Head - ----11/15/2010 ----- - - --- --ND ------Well Head - ----11/9/2011 ----- - - --- --ND ------Well Head - ----11/29/2012 ----- - - --- --ND ------Well Head - ----11/14/2013 ----- - - --- --ND ------Well Head - ----11/12/2014 ----- - - --- --ND ------Well Head - ----11/4/2015 ----- - - --- --ND ------Well Head - ----11/8/2016 ----- - - --- --ND ------Well Head - ----11/6/2017 ----- - - --- --ND ------Well Head - ----11/20/2018 ----- - - --- --ND ------Well Head - ----11/11/2019 ----- - - --- --ND ------Well Head - DUTCH SLOUGH WATER WORKS 0.2 2 20-7/21/2004 1060 --1049 23 138 2 112 111 300260 <0.09 1 7083.5 1702000 2Well Head - ----7/27/2005 ----- - - --- --<0.09 ------Well Head - 0.1 2 30-7/2/2007 1060 650 -1047 21 146 2 121 128 310260 <0.09 2 7014.2 1601820 2Well Head - ----7/3/2008 ----- - - --- --<0.09 ------Well Head - ----7/17/2009 ----- - - --- --<0.09 ------Well Head - Thursday, September 10, 2020Page 50 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer DUTCH SLOUGH WATER WORKS 0.1 2 20-7/20/2010 1050 620 -1049221492109119300250-1 9093.9 1702000 2Well Head - ----7/20/2011 ------------<0.09 ------Well Head - ----7/3/2012 ------------<0.09 ------Well Head - 0.1 2 20-12/30/2013 1090 --1049231402116129300240<0.09 1 5089.8 1701900 2Well Head - ----7/8/2014 ------------0.2 ------Well Head - ---0.512/9/2014 -------------------Well Head - ----7/8/2015 ------------<0.09 ------Well Head - 0.1 2 20-7/12/2016 1090 670 -10502314621161282902400.1 2 3084.8 1802000 1Well Head - ----7/11/2017 ------------0.4 ------Well Head - ----7/10/2018 ------------0.4 ------Well Head - ----7/15/2019 ------------<0.4 ------Well Head - 0.1 ---9/9/2019 -630 --47 22 130 7 114 119 --<0.4 -200-1601900 -Well Head - EBRPD ROUND VALLEY WATER SYSTEM ----8/19/2015 ----- - - --- --0.4 ------Well Head - ----5/11/2016 ----- - - --- --0.4 ------Well Head - ----5/17/2017 ----- - - --- --0.4 ------Well Head - ----2/7/2018 ----- - - --- --0.4 ------Well Head - EXCELSIOR MIDDLE SCHOOL ----9/7/1999 ----- - - --- -----<100 ---Well Head - ----10/4/2001 ----- - - --- --0.7 ------Well Head - ----12/6/2001 ----- - - --- -----200 ---Well Head - ----10/3/2002 ----- - - --- --ND ------Well Head - ----12/2/2002 ----- - - --- -----<100 ---Well Head - ----3/24/2003 ----- - - --- --ND ------Well Head - 0.3 <2 50-4/10/2003 1100 670 -<5023 10 210 1.3 120 100 370300 ND <10 170<100 54-<5Well Head - ----10/8/2003 ----- - - --- --ND ------Well Head - ----10/7/2004 ----- - - --- --ND ------Well Head - ----4/6/2005 ----- - - --- --ND ------Well Head - ----10/12/2006 ----- - - --- --ND ------Well Head - ----10/4/2007 ----- - - --- --ND ------Well Head - ----10/6/2008 ----- - - --- --ND ------Well Head - 0.4 3 <50-5/28/2009 1200 730 -5021 10 200 1.3 120 100 390320 ND 5.6 <100100 46-<5Well Head - ----10/5/2009 ----- - - --- --ND ------Well Head - ----10/6/2010 ----- - - --- --ND ------Well Head - ----10/5/2011 ----- - - --- --ND ------Well Head - Thursday, September 10, 2020Page 51 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer EXCELSIOR MIDDLE SCHOOL ----10/3/2012 ------------ND ------Well Head - ----4/9/2013 ------------ND ------Well Head - ----10/8/2013 ------------ND ------Well Head - ----4/3/2014 ------------ND ------Well Head - ---0.459/3/2014 -------------------Well Head - ----10/8/2014 ------------ND ------Well Head - ----10/1/2015 ------------ND ------Well Head - ----10/5/2016 ------------0.4 ------Well Head - 0.2 <2 --8/15/2017 ---<50----120 100 --0.4 <10 -<100 --5Well Head - ----6/18/2018 1120 ------------------Well Head - ----8/22/2018 ------------ND ------Well Head - ----8/21/2019 ------------ND ------Well Head - FARRAR PARK PROPERTY OWNERS ----12/27/2001 ----- - - --- --ND ------Well Head - ----12/30/2002 ----- - - --- --<0.5 ------Well Head - ----12/23/2003 ----- - - --- --<0.5 ------Well Head - -10 --6/23/2004 ----- - - --- ---------Well Head - 0.2 8.2 50-8/25/2004 1200 690 --35 19 200 2.8 130 130 300250 ND -130-130-<5Well Head - ----12/29/2004 ----- - - --- --<0.5 ------Well Head - 0.1 -<50-9/5/2007 1100 710 --36 17 180 2.9 130 130 300250 ND -120-96--Well Head - 0.1 9.6 <50-9/1/2010 1200 720 -5036 18 190 3 130 130 310250 ND 1 130100 110-<5Well Head - ----12/28/2011 ----- - - --- --<0.5 ------Well Head - ----1/5/2015 ----- - - --- --ND ------Well Head - 0.1 6.9 <50-11/30/2016 1100 680 -<5035 17 190 3 130 130 300240 ND <10 130100 130-<5Well Head - ---ND8/30/2017 ----- - - --- ---------Well Head - ----12/19/2017 ----- - - --- --0.4 ------Well Head - ----12/20/2018 ----- - - --- --ND ------Well Head - ----12/19/2019 ----- - - --- --ND ------Well Head - FLAMINGO MOBILE MANOR ----6/20/2002 ----- - - --- --ND ------Well Head - ----6/19/2003 ----- - - --- --ND ------Well Head - ----6/22/2004 ----- - - --- --ND ------Well Head - --50-7/27/2004 ---<50- - - --- ---<10 -222 400-<5Well Head - ----6/23/2005 ----- - - --- --ND ------Well Head - ----6/29/2007 ----- - - --- --ND ------Well Head - Thursday, September 10, 2020Page 52 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer FLAMINGO MOBILE MANOR ND -<50-9/5/2007 1300 750 --65 29 150 2.7 75 200 310250 ND -190-400--Well Head - ----6/18/2008 ------------ND ------Well Head - ND 6.4 <50-9/1/2010 1300 750 -5063301603.7 76 220 310250 -1 180270 410-<5Well Head - ----6/25/2013 ------------ND ------Well Head - ----6/13/2016 ------------ND ------Well Head - ND 6.4 <50ND7/21/2016 1300 750 -5059281702.8 81 210 290240 ND <10 180280 390-<5Well Head - ----7/17/2017 ------------ND ------Well Head - ----7/17/2018 ------------ND ------Well Head - ----7/16/2019 ------------ND ------Well Head - ND 8 ND-8/13/2019 ---ND56251602.6 97 210 --ND -160280 380-NDWell Head - FRANKS MARINA ----10/15/2008 ------------ND ------New Well - 0.1 <2 <50-3/9/2009 1300 820 -5024142202.1 160 170 260210 ND 2.9 <100100 140-<5New Well - ----10/19/2009 ----- - - --- --ND ------New Well - ----10/14/2010 ----- - - --- --ND ------New Well - ----10/12/2011 ----- - - --- --ND ------New Well - ----10/4/2012 ----- - - --- --ND ------New Well - ----10/3/2013 ----- - - --- --ND ------New Well - ND <2 <50-7/16/2014 1200 740 -<5027 13 230 2.4 150 170 250200 ND <10 <100120 140-<5New Well - ----10/9/2014 ----- - - --- --ND ------New Well - ----7/8/2015 ----- - - --- --ND ------New Well - ---ND7/6/2016 ----- - - --- ---------New Well - ----7/11/2016 ----- - - --- --ND ------New Well - ----7/19/2017 ----- - - --- --ND ------New Well - ND <2 <50-9/27/2017 1300 780 -<5027 13 240 2.2 160 190 250210 ND <10 <100110 140-<5New Well - ----7/10/2018 ----- - - --- --ND ------New Well - ----7/16/2019 ----- - - --- --ND ------New Well - ----10/22/2001 ----- - - --- --ND ------Well Head - ----10/17/2002 ----- - - --- --ND ------Well Head - ND <2 50-12/18/2002 1200 720 -<5028 15 230 2.3 130 180 250200 ND <10 <100130 140-<5Well Head - ----10/22/2003 ----- - - --- --ND ------Well Head - ----10/25/2004 ----- - - --- --ND ------Well Head - ----10/20/2005 ----- - - --- --ND ------Well Head - ND <2 50-3/2/2006 1200 750 -5027 14 220 2.1 160 170 250210 ND 10 110100 120-<5Well Head - GAS N SAVE Thursday, September 10, 2020Page 53 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer GAS N SAVE ----7/30/2004 ------------ND ------Well Head - ----7/26/2005 ------------ND ------Well Head - ----8/3/2006 ------------ND ------Well Head - ----9/10/2018 ------------ND ------Well Head - GENOS DELI STATION ----6/3/2002 ------------ND ------Well Head - ----6/2/2003 ------------ND ------Well Head - ----6/30/2005 ------------ND ------Well Head - ----6/29/2006 ------------ND ------Well Head - ----7/30/2007 ------------ND ------Well Head - ----9/13/2018 ------------0.4 ------Well Head - ----8/22/2019 ------------<0.4 ------Well Head - HOLLAND RIVERSIDE MARINA ----12/28/2001 ----- - - --- --ND ------well 2 - East Well - ----12/31/2002 ----- - - --- --ND ------well 2 - East Well - ----12/31/2003 ----- - - --- --ND ------well 2 - East Well - ----12/29/2004 ----- - - --- --<0.5 ------well 2 - East Well - ----12/27/2005 ----- - - --- --ND ------well 2 - East Well - ----12/20/2006 ----- - - --- --ND ------well 2 - East Well - ----9/20/2010 ----- - - --- --<0.2 ------well 2 - East Well - ----12/2/2010 ----- - - --- --<0.2 ------well 2 - East Well - ----9/26/2011 ----- - - --- --<0.2 ------well 2 - East Well - ----9/20/2012 ----- - - --- --<0.2 ------well 2 - East Well - ----8/27/2014 ----- - - --- --<0.2 ------well 2 - East Well - ----11/10/2015 ----- - - --- --ND ------well 2 - East Well - ----9/22/2016 ----- - - --- --ND ------well 2 - East Well - ----9/12/2017 ----- - - --- --ND ------well 2 - East Well - ----9/4/2018 ----- - - --- --ND ------well 2 - East Well - ----12/28/2001 ----- - - --- --ND ------Well Head - West Well - ----12/31/2002 ----- - - --- --ND ------Well Head - West Well - ----12/31/2003 ----- - - --- --ND ------Well Head - West Well - ----12/29/2004 ----- - - --- --<0.5 ------Well Head - West Well - ----12/20/2006 ----- - - --- --ND ------Well Head - West Well - ----12/16/2008 ----- - - --- --ND ------Well Head - West Well - ----12/15/2009 ----- - - --- --ND ------Well Head - West Well - Thursday, September 10, 2020Page 54 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer HOLLAND RIVERSIDE MARINA ----9/20/2010 ------------<0.2 ------Well Head - West Well - ----12/2/2010 ------------<0.2 ------Well Head - West Well - ----9/26/2011 ------------<0.2 ------Well Head - West Well - ----9/20/2012 ------------<0.2 ------Well Head - West Well - ----11/10/2015 ------------ND ------Well Head - West Well - HOLY CROSS CEMETERY ----7/11/2002 ------------1.4 ------Well Head - ----7/15/2003 ------------1.8 ------Well Head - ----7/7/2004 ------------2.1 ------Well Head - ----7/7/2005 ------------2.1 ------Well Head - ----7/10/2006 ------------1.9 ------Well Head - ----7/7/2008 ------------2.5 ------Well Head - ----7/15/2009 ------------2.7 ------Well Head - ----7/14/2010 ----- - - --- --3.2 ------Well Head - ----7/18/2012 ----- - - --- --3.2 ------Well Head - ----7/22/2013 ----- - - --- --3.2 ------Well Head - ----7/21/2014 ----- - - --- --3.2 ------Well Head - ----7/18/2016 ----- - - --- --3.7 ------Well Head - ----7/20/2017 ----- - - --- --3.3 ------Well Head - ----7/18/2018 ----- - - --- --3.7 ------Well Head - ----7/22/2019 ----- - - --- --3.3 ------Well Head - JOES ISLAND RESTAURANT ----9/18/2008 ----- - - --- --ND ------WELLHEAD - ----10/26/2017 ----- - - --- --ND ------WELLHEAD - ----10/29/2018 ----- - - --- --ND ------WELLHEAD - ----10/9/2019 ----- - - --- --ND ------WELLHEAD - LAST RESORT & MARINA LLC ----7/23/2002 ----- - - --- --ND ------Well Head - ----7/31/2003 ----- - - --- --ND ------Well Head - ----7/28/2004 ----- - - --- --ND ------Well Head - ----7/21/2005 ----- - - --- --ND ------Well Head - ----7/24/2006 ----- - - --- --ND ------Well Head - LIGHTHOUSE BAPTIST CHURCH Thursday, September 10, 2020Page 55 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer LIGHTHOUSE BAPTIST CHURCH ----6/6/2002 ------------6.3 ------Well Head - ----6/5/2003 ------------5.6 ------Well Head - LINDQUIST LANDING MARINA ----12/28/2001 ------------ND ------Well Head - ----11/24/2003 ------------ND ------Well Head - ----12/31/2003 ------------ND ------Well Head - ----12/27/2004 ------------ND ------Well Head - ----12/27/2005 ------------ND ------Well Head - ----12/29/2006 ------------ND ------Well Head - ----12/20/2007 ------------ND ------Well Head - ----12/10/2008 ------------ND ------Well Head - ----12/15/2009 ------------ND ------Well Head - ----12/28/2010 ------------ND ------Well Head - ----6/12/2012 ----- - - --- --<0.09 ------Well Head - ----6/4/2013 ----- - - --- --<0.09 ------Well Head - ----6/9/2015 ----- - - --- --<0.09 ------Well Head - ----6/2/2016 ----- - - --- --0.1 ------Well Head - ----6/20/2017 ----- - - --- --0.4 ------Well Head - ----7/2/2018 ----- - - --- --0.4 ------Well Head - ----7/8/2019 ----- - - --- --<0.4 ------Well Head - LITTORNO & PANFILI WATER SYSTEM ----8/5/2004 ----- - - --- --3.2 ------WELL HEAD - ----8/3/2005 ----- - - --- --2.9 ------WELL HEAD - ----8/8/2006 ----- - - --- --2.2 ------WELL HEAD - LOS VAQUEROS INTERPRETIVE CENTER 0.1 2.2 50-10/21/2009 420 --16020 12 37 -34 47 100100 -10 100140 20-5SOURCE- 0.1 ---2/17/2010 410 ---- - 36 -31 45 -100 --120-20--SOURCE - 0.1 2 50-10/6/2010 400 -8 12027 12 37 3.1 30 46 100100 -10 150130 20-5SOURCE- 0.1 2 50-10/21/2011 440 --23023 12 37 2.9 33 50 110110 -10 140180 20-5SOURCE- 0.1 ---9/12/2012 350 ---- - 36 -26 49 -90 -------SOURCE - 0.1 2 50-10/2/2012 350 -7.5 10025 11 38 2.6 26 52 9090 -10 130160 20-5SOURCE- 0.1 ---10/8/2013 430 -8 -- - - -42 51 7878 -------SOURCE - 0.2 ---10/7/2014 450 -7.9 -- - - -26 56 -100 -------SOURCE - ----7/5/2016 ----- - - --- --ND ------SOURCE - Thursday, September 10, 2020Page 56 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer LOS VAQUEROS INTERPRETIVE CENTER -2 50-10/4/2016 ---1602611372.4 ---100 -10 180140 20-5SOURCE- ----1/10/2017 ------------ND ------SOURCE - ----4/4/2017 ------------ND ------SOURCE - -2 50110/3/2017 440 --503111372.4 28 53 --0.4 10 100130 20-5SOURCE- LOS VAQUEROS MARINA BLDG 0.1 2.2 50-10/21/2009 420 --160201237-34 47 100100 -10 100140 20-5SOURCE- 0.1 ---2/17/2010 410 -----36 -31 45 -100 --120-20--SOURCE - 0.1 2 50-10/6/2010 400 -8 1202712373.1 30 46 100100 -10 150130 20-5SOURCE- 0.1 2 50-10/21/2011 440 --2302312372.9 33 50 110110 -10 140180 20-5SOURCE- 0.1 ---9/12/2012 350 -----36 -26 49 -90 -------SOURCE - 0.1 2 50-10/2/2012 350 -7.5 1002511382.6 26 52 9090 -10 130160 20-5SOURCE- 0.1 ---10/8/2013 430 -8 -----42 51 7878 -------SOURCE - 0.2 ---10/7/2014 450 -7.9 -----26 56 -100 -------SOURCE - ----7/5/2016 ----- - - --- --ND ------SOURCE - -2 50-10/4/2016 ---16026 11 37 2.4 -- -100 -10 180140 20-5SOURCE- ----1/10/2017 ----- - - --- --ND ------SOURCE - ----4/4/2017 ----- - - --- --ND ------SOURCE - -2 50110/3/2017 440 --5031 11 37 2.4 28 53 --0.4 10 100130 20-5SOURCE- LUNDBORG LANDING *CL 2/09 0.1 2 20-11/16/2005 1370 780 -1031 15 205 2 115 250 230190 <0.09 1 320182 1401500 2well- ----10/4/2006 ----- - - --- --<0.09 ------well - ----10/26/2007 ----- - - --- --<0.09 ------well - MACS OLD HOUSE ----9/17/2001 ----- - - --- --5.6 ------Well Head - ----12/18/2001 ----- - - --- --7 ------Well Head - ----3/14/2002 ----- - - --- --4.7 ------Well Head - ----6/13/2002 ----- - - --- --7.5 ------Well Head - ----9/12/2002 ----- - - --- --6.3 ------Well Head - ----12/17/2002 ----- - - --- --5 ------Well Head - ----3/20/2003 ----- - - --- --2.5 ------Well Head - ----12/30/2003 ----- - - --- --7 ------Well Head - ----3/17/2004 ----- - - --- --1.3 ------Well Head - ----6/15/2004 ----- - - --- --10 ------Well Head - Thursday, September 10, 2020Page 57 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer MARINA MOBILE MANOR ----9/14/2011 ------------ND ------NEW WELL - ----9/20/2012 ------------ND ------NEW WELL - ND <2 <50-7/18/2013 1400 --<5085471503.3 100 200 350290 ND <10 190100 380-<5NEW WELL - ----9/16/2013 ------------ND ------NEW WELL - ---ND9/15/2014 ------------ND ------NEW WELL - ----9/16/2015 ------------ND ------NEW WELL - ND <2 <50-7/6/2016 1300 --5075371402.9 110 200 350290 ND <10 170100 370-<5NEW WELL - ----7/27/2017 ------------ND ------NEW WELL - ----7/23/2018 ------------ND ------NEW WELL - ND 3 ND-8/1/2019 -840 -ND76421403.1 110 190 --ND ND 200-370-NDNEW WELL - ----12/27/2001 ------------ND ------Well Head - 0.1 6.6 --4/28/2003 ---<50--------ND <10 -<100 --<5Well Head - --50-7/26/2004 1100 670 --38 20 170 2.4 95 130 190160 ND -130-170--Well Head - ----12/28/2005 ------------ND ------Well Head - ----12/11/2006 ----- - - --- --ND ------Well Head - 0.19 6.4 <50-7/25/2007 1100 710 -5035 19 180 2.4 80 120 370300 ND 10 120100 180-5Well Head - ----12/28/2007 ----- - - --- --ND ------Well Head - ----12/23/2008 ----- - - --- --0.56 ------Well Head - ----12/22/2009 ----- - - --- --0.5 ------Well Head - 0.1 6.9 <50-7/19/2010 1100 700 -5036 19 170 2.4 91 130 370300 -1 <100100 170-<5Well Head - ----8/26/2010 ----- - - --- --ND ------Well Head - ----9/23/2010 ----- - - --- --ND ------Well Head - MARINER COVE MARINA ----11/29/2001 ----- - - --- --ND ------Well Head - ----11/27/2002 ----- - - --- --ND ------Well Head - ----11/18/2004 ----- - - --- --ND ------Well Head - ----11/27/2006 ----- - - --- --ND ------Well Head - ----11/27/2007 ----- - - --- --ND ------Well Head - ----11/24/2008 ----- - - --- --ND ------Well Head - ----11/30/2009 ----- - - --- --ND ------Well Head - ----11/23/2010 ----- - - --- --ND ------Well Head - ----11/28/2011 ----- - - --- --ND ------Well Head - ----11/29/2012 ----- - - --- --ND ------Well Head - ----11/25/2014 ----- - - --- --ND ------Well Head - ----11/23/2015 ----- - - --- --ND ------Well Head - ----11/29/2016 ----- - - --- --ND ------Well Head - Thursday, September 10, 2020Page 58 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer MARINER COVE MARINA ----11/21/2017 ------------ND ------Well Head - ----11/20/2018 ------------ND ------Well Head - ----11/11/2019 ------------ND ------Well Head - NEIGHBORHOOD CHURCH ----5/23/2002 ------------8.1 ------Well Head - ----5/14/2003 ------------8.8 ------Well Head - ----5/13/2004 ------------8.4 ------Well Head - ----5/16/2005 ------------8.8 ------Well Head - ----5/8/2006 ------------9.9 ------Well Head - ----5/7/2007 ------------11 ------Well Head - ----5/7/2009 ------------8.6 ------Well Head - ----5/6/2010 ------------9.3 ------Well Head - ----5/9/2011 ------------9.7 ------Well Head - ----5/14/2012 ----- - - --- --10 ------Well Head - ----5/2/2013 ----- - - --- --10 ------Well Head - ----5/1/2014 ----- - - --- --9.9 ------Well Head - ---7.69/2/2014 ----- - - --- ---------Well Head - ----5/3/2016 ----- - - --- --10 ------Well Head - ----5/2/2017 ----- - - --- --10 ------Well Head - 0.23 <2 1808.68/14/2017 1600 1100 -190160 60 140 2.7 230 240 340280 11 10 <100100 <20-5Well Head - ----5/31/2018 ----- - - --- --11 ------Well Head - ----7/11/2018 ----- - - --- --11 ------Well Head - NEW DOCS MARINA ----3/27/2002 ----- - - --- --ND ------Well Head - ----3/27/2003 ----- - - --- --ND ------Well Head - ----5/22/2008 ----- - - --- --ND ------Well Head - ----5/21/2009 ----- - - --- --ND ------Well Head - ----5/24/2010 ----- - - --- --ND ------Well Head - ----5/25/2011 ----- - - --- --ND ------Well Head - ----5/24/2012 ----- - - --- --ND ------Well Head - ----5/22/2014 ----- - - --- --ND ------Well Head - ----5/28/2015 ----- - - --- --ND ------Well Head - ----5/18/2016 ----- - - --- --ND ------Well Head - ----5/31/2017 ----- - - --- --ND ------Well Head - ----12/4/2018 ----- - - --- --ND ------Well Head - Thursday, September 10, 2020Page 59 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer NEW DOCS MARINA ----11/25/2019 ------------0.7 ------Well Head - OAKLEY MUTUAL WATER COMPANY ----6/21/2004 ------------ND ------NORTH WELL - 4384 SANDMOUND - ----6/20/2005 ------------ND ------NORTH WELL - 4384 SANDMOUND - ----6/21/2006 ------------ND ------NORTH WELL - 4384 SANDMOUND - 0.1 -<50-1/29/2007 1200 880 --16 11 230 1.6 84 150 360290 ND -<100-130--NORTH WELL - 4384 SANDMOUND - ----6/27/2007 ------------ND ------NORTH WELL - 4384 SANDMOUND - ----6/12/2008 ------------ND ------NORTH WELL - 4384 SANDMOUND - ----6/22/2009 ------------ND ------NORTH WELL - 4384 SANDMOUND - ----6/17/2010 ------------ND ------NORTH WELL - 4384 SANDMOUND - ----6/15/2011 ------------ND ------NORTH WELL - 4384 SANDMOUND - ----6/18/2012 ------------ND ------NORTH WELL - 4384 SANDMOUND - ----6/20/2013 ------------ND ------NORTH WELL - 4384 SANDMOUND - ----6/18/2014 ----- - - --- --ND ------NORTH WELL - 4384 SANDMOUND - ---0.2110/28/2014 ----- - - --- ---------NORTH WELL - 4384 SANDMOUND - ----7/1/2015 ----- - - --- --ND ------NORTH WELL - 4384 SANDMOUND - ----6/13/2016 ----- - - --- --ND ------NORTH WELL - 4384 SANDMOUND - ND 13 <50-7/6/2016 1200 690 -<5018 10 220 1.7 81 140 350290 0.4 <10 <100100 140-<5NORTH WELL - 4384 SANDMOUND - ----8/16/2017 ----- - - --- --0.4 ------NORTH WELL - 4384 SANDMOUND - ND 13 <50-7/30/2019 -730 -ND19 11 -1.9 79 140 --<0.4 ND ND<100 140-<5NORTH WELL - 4384 SANDMOUND - 0.2 <2 50-3/20/2002 960 580 -<5060 28 110 2 100 85 -290 <0.5 <10 140<100 170-<5SOUTH WELL - 4508 SANDMOUND - ----6/21/2004 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - ----6/20/2005 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - ----6/21/2006 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - -12 --1/29/2007 ---50- - - --- ---10 -100 --5SOUTH WELL - 4508 SANDMOUND - ----6/27/2007 ----- - - --- --<0.5 ------SOUTH WELL - 4508 SANDMOUND - ----6/12/2008 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - ----6/22/2009 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - 0.1 12 <50-2/17/2010 1200 710 -5019 11 210 1.7 83 150 360290 ND 8.1 100100 140-<5SOUTH WELL - 4508 SANDMOUND - ----6/17/2010 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - ----6/15/2011 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - ----6/18/2012 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - ----6/20/2013 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - ----6/18/2014 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - ---ND10/28/2014 ----- - - --- ---------SOUTH WELL - 4508 SANDMOUND - ----7/1/2015 ----- - - --- --ND ------SOUTH WELL - 4508 SANDMOUND - Thursday, September 10, 2020Page 60 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer OAKLEY MUTUAL WATER COMPANY ----6/13/2016 ------------ND ------SOUTH WELL - 4508 SANDMOUND - ND 13 <50-7/6/2016 1200 --<5019112201.7 81 140 350290 ND <10 <100100 140-<5SOUTH WELL - 4508 SANDMOUND - ----8/16/2017 ------------ND ------SOUTH WELL - 4508 SANDMOUND - ----8/1/2018 ------------ND ------SOUTH WELL - 4508 SANDMOUND - ND -<50-8/21/2019 ---ND20112001.8 76 ---ND ND NDND 160-<5WELL 3 - ORIN ALLEN YOUTH REHAB FACILITY -2.6 <50-1/27/2004 1300 --<507.3 5 270 0.6 96 110 480400 -<10 430<100 79-<5WELL- 0.7 4.4 <50-2/17/2010 1200 --50187.1 240 0.9 120 130 400320 -13 310100 38-<5WELL- 0.45 2.5 50-2/11/2013 1200 --50188.5 260 1.2 120 140 400330 -1 750100 130-<5WELL- 0.32 4.3 --4/13/2016 ---<50--------ND <10 -100 --<5WELL- ---ND8/15/2017 -------------------Well 2 - ----1/16/2019 ------------ND ------Well 2 - 0.5 6 <50-2/5/2019 -880 -ND209.8 300 1.1 120 190 --ND ND 290<100 80-NDWell 2 - ORWOOD RESORT 0.3 <2 91-9/30/2002 910 510 --58 24 110 1.7 98 78 -270 ND -210-150-<5WELL 2 - WEST WELL - ----6/28/2004 ----- - - --- --ND ------WELL 2 - WEST WELL - ----6/28/2005 ----- - - --- --ND ------WELL 2 - WEST WELL - 0.2 <2 50-6/20/2006 910 570 -5057 23 100 1.4 92 80 340280 ND 10 160100 160-<5WELL 2 - WEST WELL - ----6/28/2007 ----- - - --- --ND ------WELL 2 - WEST WELL - ----6/17/2008 ----- - - --- --ND ------WELL 2 - WEST WELL - ----6/16/2009 ----- - - --- --ND ------WELL 2 - WEST WELL - 0.2 <2 <50-6/28/2010 920 570 -5056 24 100 1.5 110 78 330270 -1 200100 140-<5WELL 2 - WEST WELL - ----6/19/2012 ----- - - --- --ND ------WELL 2 - WEST WELL - ----6/18/2013 ----- - - --- --ND ------WELL 2 - WEST WELL - ----6/17/2014 ----- - - --- --ND ------WELL 2 - WEST WELL - ----6/13/2017 ----- - - --- --ND ------WELL 2 - WEST WELL - 0.1 <2 <50ND7/24/2017 920 570 -5053 23 110 1.6 100 76 330270 ND <10 190100 140-<5WELL 2 - WEST WELL - ----7/2/2018 ----- - - --- --0.4 ------WELL 2 - WEST WELL - 0.2 <2 40-9/30/2002 910 540 -<5059 24 110 1.6 100 78 -260 ND <10 100<100 160-<5WELL 3 - PICNIC AREA - ----6/28/2004 ----- - - --- --ND ------WELL 3 - PICNIC AREA - ----6/28/2005 ----- - - --- --ND ------WELL 3 - PICNIC AREA - 0.2 <2 50-6/20/2006 910 560 -5055 22 110 1.5 100 80 330270 ND 10 190100 150-<5WELL 3 - PICNIC AREA - ----6/28/2007 ----- - - --- --ND ------WELL 3 - PICNIC AREA - ----6/17/2008 ----- - - --- --ND ------WELL 3 - PICNIC AREA - Thursday, September 10, 2020Page 61 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer ORWOOD RESORT ----6/15/2009 ------------ND ------WELL 3 - PICNIC AREA - ----6/28/2011 ------------ND ------WELL 3 - PICNIC AREA - ---ND8/26/2014 -------------------WELL 3 - PICNIC AREA - PARK MARINA ----5/25/2004 ------------ND ------Well Head - ----6/29/2006 ------------ND ------Well Head - ----6/29/2007 ------------ND ------Well Head - ----7/1/2008 ------------ND ------Well Head - ----6/15/2009 ------------ND ------Well Head - ----6/10/2010 ------------ND ------Well Head - ----6/21/2011 ------------ND ------Well Head - ----6/27/2012 ------------ND ------Well Head - ----6/19/2013 ------------ND ------Well Head - ----6/23/2014 ----- - - --- --ND ------Well Head - ----6/25/2015 ----- - - --- --ND ------Well Head - PLEASANTIMES MUTUAL WATER CO ----5/21/2003 ----- - - --- --0.1 ------WELL 2 - 4520 STONE - 0.1 -20-6/23/2004 1380 830 --34 15 238 2 162 212 260220 <0.09 -200-1502600 -WELL 2 - 4520 STONE - ----5/18/2005 ----- - - --- --<0.09 ------WELL 2 - 4520 STONE - -6 --6/1/2005 ----- - - --- ---------WELL 2 - 4520 STONE - -9 --5/9/2006 ---10- - - --- ---1 -182 --2WELL 2 - 4520 STONE - -5 --11/21/2006 ----- - - --- ---------WELL 2 - 4520 STONE - --<50-7/24/2007 1400 870 --32 14 240 1.9 150 200 280230 ND -110-160--WELL 2 - 4520 STONE - ND 5 --5/24/2010 ---50- - - --- --ND 1 -120 --<5WELL 2 - 4520 STONE - --<50-6/28/2010 1400 850 --32 14 240 2 160 210 260220 --<100-140--WELL 2 - 4520 STONE - ----5/23/2011 ----- - - --- --ND ------WELL 2 - 4520 STONE - ND <2 <50-5/20/2013 1700 940 -<5041 21 270 2.9 98 340 240200 ND 5 <100140 160-<5WELL 2 - 4520 STONE - ----5/19/2014 ----- - - --- --ND ------WELL 2 - 4520 STONE - ---ND8/25/2014 ----- - - --- ---------WELL 2 - 4520 STONE - ----5/18/2015 ----- - - --- --ND ------WELL 2 - 4520 STONE - ND 4.3 <50-5/23/2016 1400 850 -<5030 14 250 2 160 200 260210 ND <10 100170 140-<5WELL 2 - 4520 STONE - ----5/22/2017 ----- - - --- --ND ------WELL 2 - 4520 STONE - -5 ND-5/6/2019 -840 -ND32 15 260 2.4 -230 --ND ND ND160 --<5WELL 2 - 4520 STONE - ----5/20/2019 ----- - - --- --ND ------WELL 2 - 4520 STONE - ----5/21/2003 ----- - - --- --<0.09 ------Well 1 - 4282 STONE - Thursday, September 10, 2020Page 62 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer PLEASANTIMES MUTUAL WATER CO 0.1 -20-6/23/2004 1410 850 --32 18 235 2 156 223 270220 <0.09 -80-1302600 -Well 1 - 4282 STONE - ----5/18/2005 ------------<0.09 ------Well 1 - 4282 STONE - -6 --6/1/2005 -------------------Well 1 - 4282 STONE - -6 --5/9/2006 ---20--------<0.09 1 -149 --2Well 1 - 4282 STONE - -5.3 --11/21/2006 -------------------Well 1 - 4282 STONE - --<50-7/24/2007 1400 860 --30 16 250 1.9 140 210 290240 ND -160-140--Well 1 - 4282 STONE - ----5/26/2009 ------------ND ------Well 1 - 4282 STONE - ND 4 --5/24/2010 ---50--------ND 1 -150 --<5Well 1 - 4282 STONE - --<50-6/28/2010 1400 860 --30 16 250 2 150 220 290240 --<100-120--Well 1 - 4282 STONE - ----5/23/2011 ------------ND ------Well 1 - 4282 STONE - ----5/21/2012 ------------ND ------Well 1 - 4282 STONE - ND 5.7 <50-5/20/2013 1400 840 -<5030162502.5 150 210 270220 ND 5 210120 120-<5Well 1 - 4282 STONE - ----5/19/2014 ------------ND ------Well 1 - 4282 STONE - ---ND8/25/2014 -------------------Well 1 - 4282 STONE - ----5/18/2015 ----- - - --- --ND ------Well 1 - 4282 STONE - ND 5 50-5/23/2016 1400 --<5030 17 250 2.1 150 220 270220 ND <10 100120 120-<5Well 1 - 4282 STONE - ----5/22/2017 ----- - - --- --ND ------Well 1 - 4282 STONE - ----12/17/2018 ----- - - --- --ND ------Well 1 - 4282 STONE - ND 6 ND-5/6/2019 -860 -ND30 - 260 2.3 160 250 ---ND ND120 --<5Well 1 - 4282 STONE - ----5/20/2019 ----- - - --- --ND ------Well 1 - 4282 STONE - ----5/21/2003 ----- - - --- --<0.09 ------WELL 3 - 4441 WILLOW - 0.3 -140-6/23/2004 1560 880 --38 20 250 2 114 316 240200 <0.09 -120-1701700 -WELL 3 - 4441 WILLOW - ----5/18/2005 ----- - - --- --<0.09 ------WELL 3 - 4441 WILLOW - -2 --6/1/2005 ----- - - --- ---------WELL 3 - 4441 WILLOW - -2 --5/9/2006 ---10- - - --- --<0.09 1 -144 --2WELL 3 - 4441 WILLOW - -2 --11/21/2006 ----- - - --- ---------WELL 3 - 4441 WILLOW - --<50-7/24/2007 1600 960 --37 19 270 2.3 94 310 240200 ND -<100-180--WELL 3 - 4441 WILLOW - ND <2 --5/24/2010 ---50- - - --- --ND 1 -140 --<5WELL 3 - 4441 WILLOW - --<50-6/28/2010 1700 920 --40 21 270 2.4 100 350 250200 --<100-170--WELL 3 - 4441 WILLOW - ----5/23/2011 ----- - - --- --ND ------WELL 3 - 4441 WILLOW - ----5/21/2012 ----- - - --- --ND ------WELL 3 - 4441 WILLOW - ND 5.2 <50-5/20/2013 1400 810 -<5032 15 250 2.5 160 210 280230 ND 5 110150 140-<5WELL 3 - 4441 WILLOW - ----5/19/2014 ----- - - --- --ND ------WELL 3 - 4441 WILLOW - ---ND8/25/2014 ----- - - --- ---------WELL 3 - 4441 WILLOW - ----5/18/2015 ----- - - --- --ND ------WELL 3 - 4441 WILLOW - ND <2 <50-5/23/2016 1600 --<5037 20 280 2.5 100 350 240190 ND <10 100140 170-<5WELL 3 - 4441 WILLOW - ----5/22/2017 ----- - - --- --ND ------WELL 3 - 4441 WILLOW - Thursday, September 10, 2020Page 63 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer PLEASANTIMES MUTUAL WATER CO ----12/17/2018 ------------ND ------WELL 3 - 4441 WILLOW - ND ND ND-5/6/2019 -980 -ND40212902.7 100 380 --ND ND -140 170-<5WELL 3 - 4441 WILLOW - RIVERVIEW MARINA SWS ND <2 50-10/22/2001 1200 --<5031162202.5 150 200 -190 ND <10 100200 140-<5Well Head - ----6/22/2004 ------------ND ------Well Head - ----9/4/2019 ------------ND ------Well Head - RIVERVIEW WATER ASSOCIATION ----6/23/2004 ------------ND ------WELL 1 BEACON HARBOR - ND <2 50-7/15/2004 1800 1100 -<5049242803.1 94 310 260210 ND <10 100148 160-<5WELL 1 BEACON HARBOR - ----6/23/2005 ------------ND ------WELL 1 BEACON HARBOR - ----6/22/2006 ------------ND ------WELL 1 BEACON HARBOR - ----6/28/2007 ------------ND ------WELL 1 BEACON HARBOR - 0.1 2 <50-7/25/2007 1800 1100 -5050 28 290 3.4 110 380 260220 ND 10 <100165 180-5WELL 1 BEACON HARBOR - ----6/16/2008 ----- - - --- --ND ------WELL 1 BEACON HARBOR - ----6/8/2009 ----- - - --- --ND ------WELL 1 BEACON HARBOR - ----6/7/2010 ----- - - --- --ND ------WELL 1 BEACON HARBOR - ND 3.4 --9/1/2010 2300 1300 -5064 35 300 4 55 540 250210 ND 1 <100100 220-<5WELL 1 BEACON HARBOR - ----6/20/2011 ----- - - --- --ND ------WELL 1 BEACON HARBOR - ----6/5/2013 ----- - - --- --ND ------WELL 1 BEACON HARBOR - 0.1 2 50-9/22/2013 -1000 -5049 25 270 3.6 120 390 280230 -10 100180 170-5WELL 1 BEACON HARBOR - ----6/9/2014 ----- - - --- --ND ------WELL 1 BEACON HARBOR - ---ND8/6/2014 ----- - - --- ---------WELL 1 BEACON HARBOR - ----6/1/2015 ----- - - --- --ND ------WELL 1 BEACON HARBOR - ND <2 <50-11/30/2016 1800 1000 -<5045 24 280 3.5 120 350 260210 0.4 <10 <100170 150-<5WELL 1 BEACON HARBOR - ----6/7/2017 ----- - - --- --ND ------WELL 1 BEACON HARBOR - ----6/12/2018 ----- - - --- --ND ------WELL 1 BEACON HARBOR - ----6/6/2019 ----- - - --- --ND ------WELL 1 BEACON HARBOR - ND 4 <50-9/18/2019 -1300 -ND61 32 320 4.4 78 490 --0.5 ND ND190 100-<5WELL 1 BEACON HARBOR - ----6/23/2004 ----- - - --- --<0.5 ------WELL 2 END OF WILLOW RD - ND <2 50-7/15/2004 1600 930 -<5065 39 210 2.9 31 320 410340 ND <10 100155 250-<5WELL 2 END OF WILLOW RD - ----6/23/2005 ----- - - --- --0.61 ------WELL 2 END OF WILLOW RD - ----6/22/2006 ----- - - --- --0.5 ------WELL 2 END OF WILLOW RD - ND 2.7 <50-7/25/2007 2200 1200 -5068 40 300 3.4 39 500 300240 ND 10 120207 280-5WELL 2 END OF WILLOW RD - ----6/16/2008 ----- - - --- --ND ------WELL 2 END OF WILLOW RD - ----6/7/2010 ----- - - --- --ND ------WELL 2 END OF WILLOW RD - Thursday, September 10, 2020Page 64 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer RIVERVIEW WATER ASSOCIATION ND 5.9 <50-9/1/2010 2400 --5072373303.9 47 560 260210 ND 1 100180 250-<5WELL 2 END OF WILLOW RD - ----6/20/2011 ------------ND ------WELL 2 END OF WILLOW RD - ----6/6/2012 ------------ND ------WELL 2 END OF WILLOW RD - ----6/5/2013 ------------ND ------WELL 2 END OF WILLOW RD - 0.1 5.5 50-9/22/2013 -1200 -5071403003.8 47 550 290230 -10 100220 280-5WELL 2 END OF WILLOW RD - ----6/9/2014 ------------ND ------WELL 2 END OF WILLOW RD - ---ND8/6/2014 -------------------WELL 2 END OF WILLOW RD - ----6/1/2015 ------------ND ------WELL 2 END OF WILLOW RD - ND 4.7 <50-11/30/2016 2500 1300 -5069363204.1 44 550 250210 ND <10 100210 260-<5WELL 2 END OF WILLOW RD - ----6/7/2017 ------------ND ------WELL 2 END OF WILLOW RD - ----6/12/2018 ------------ND ------WELL 2 END OF WILLOW RD - ----6/6/2019 ------------ND ------WELL 2 END OF WILLOW RD - ND 6 --9/18/2019 -1600 -ND67353404.5 48 580 ---ND ND190 270--WELL 2 END OF WILLOW RD - RUSSOS MOBILE PARK ND <2 50-10/22/2003 1400 --<5036 20 230 2.9 160 230 260220 -<10 <100<100 160-<5Well Head - ND ---9/22/2006 ----- - - --- ---------Well Head - -2 --10/18/2006 ---<50- - - --- ---<10 -150 --<5Well Head - ----10/13/2009 ---50- - - --- ---10 -160 ---Well Head - 0.1 <2 <50-10/15/2009 1400 ---42 20 250 2.6 150 240 260220 --110-170-<5Well Head - ND <2 <50-11/14/2012 1400 --5037 19 260 2.8 170 270 260210 -1 <100160 180-<5Well Head - ----8/2/2017 ----- - - --- --ND ------Well Head - ND <2 <50ND9/13/2017 1500 --5036 19 310 3.1 160 250 260210 ND <10 <100170 170-<5Well Head - ----8/6/2018 ----- - - --- --ND ------Well Head - SANDMOUND MUTUAL 0.2 <2 --2/26/2003 ---<50- - - --- ---<10 -172 --<53160 STONE ROAD WELL - ----7/26/2004 ----- - - --- --ND ------3160 STONE ROAD WELL - -<2 --3/22/2005 ----- - - --- ---------3160 STONE ROAD WELL - 0.1 <2 <50-9/1/2009 1300 800 --75 40 140 2.5 110 180 380310 ND -250-330-<53160 STONE ROAD WELL - ----7/11/2012 ----- - - --- --ND ------3160 STONE ROAD WELL - 0.2 <2 <50-9/20/2012 1500 800 -5076 44 150 3 130 220 380310 ND 1 240180 390-<53160 STONE ROAD WELL - ----7/15/2013 ----- - - --- --ND ------3160 STONE ROAD WELL - ----7/9/2014 ----- - - --- --ND ------3160 STONE ROAD WELL - ----7/9/2015 ----- - - --- --ND ------3160 STONE ROAD WELL - ----7/12/2016 ----- - - --- --ND ------3160 STONE ROAD WELL - ----7/31/2017 ----- - - --- --ND ------3160 STONE ROAD WELL - Thursday, September 10, 2020Page 65 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer SANDMOUND MUTUAL ----7/31/2018 ------------ND ------3160 STONE ROAD WELL - ND <2 50-9/19/2018 1500 910 -5087441703.2 130 230 360290 ND <10 180200 360-<53160 STONE ROAD WELL - ----7/29/2019 ------------ND ------3160 STONE ROAD WELL - ND 15 --2/26/2003 ---<50--------ND <10 -160 --<53810 STONE ROAD WELL - ----6/22/2004 ------------ND ------3810 STONE ROAD WELL - -<2 --3/28/2005 -------------------3810 STONE ROAD WELL - ----7/19/2005 ------------ND ------3810 STONE ROAD WELL - ----6/21/2006 ------------ND ------3810 STONE ROAD WELL - ----7/20/2006 ------------ND ------3810 STONE ROAD WELL - ----6/29/2007 ------------ND ------3810 STONE ROAD WELL - ----7/26/2007 ------------0.5 ------3810 STONE ROAD WELL - ----6/23/2008 ------------ND ------3810 STONE ROAD WELL - ----6/23/2009 ------------ND ------3810 STONE ROAD WELL - ----7/22/2009 ------------ND ------3810 STONE ROAD WELL - ND 14 <50-9/1/2009 1800 1100 -5044 24 320 2.6 190 320 370300 ND 6.8 190130 140-<53810 STONE ROAD WELL - ----6/10/2010 ----- - - --- --ND ------3810 STONE ROAD WELL - ----7/14/2010 ----- - - --- --ND ------3810 STONE ROAD WELL - -9 --11/17/2010 ----- - - --- --ND ------3810 STONE ROAD WELL - ----6/13/2011 ----- - - --- --ND ------3810 STONE ROAD WELL - ----6/11/2012 ----- - - --- --ND ------3810 STONE ROAD WELL - ND 16 <50-9/20/2012 2000 1100 -5041 26 310 2.8 200 340 310250 ND 1 130100 150-<53810 STONE ROAD WELL - ----6/17/2013 ----- - - --- --ND ------3810 STONE ROAD WELL - ----6/12/2014 ----- - - --- --ND ------3810 STONE ROAD WELL - ----6/4/2015 ----- - - --- --ND ------3810 STONE ROAD WELL - ----6/6/2016 ----- - - --- --ND ------3810 STONE ROAD WELL - ----6/12/2017 ----- - - --- --ND ------3810 STONE ROAD WELL - ----6/26/2018 ----- - - --- --ND ------3810 STONE ROAD WELL - ND 16 <50-9/19/2018 1800 1100 -<5046 23 330 2.9 200 320 300240 ND <10 120120 140-<53810 STONE ROAD WELL - ----6/5/2019 ----- - - --- --ND ------3810 STONE ROAD WELL - SANDY POINT MOBILE HOME PARK ----12/27/2001 ----- - - --- --0.61 ------Well Head - ----12/18/2002 ----- - - --- --0.66 ------Well Head - 0.2 <2 --3/24/2003 ---<50- - - --- --ND 5 -129 --<5Well Head - ----12/15/2003 ----- - - --- --0.56 ------Well Head - --50-8/24/2004 1300 720 --57 39 150 2.6 110 150 360290 --180-300--Well Head - ----12/20/2004 ----- - - --- --0.77 ------Well Head - Thursday, September 10, 2020Page 66 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer SANDY POINT MOBILE HOME PARK ----12/20/2005 ------------ND ------Well Head - ----12/11/2006 ------------0.61 ------Well Head - 0.2 -<50-9/5/2007 1300 830 --73 40 150 2.7 120 180 370300 ND -180-290--Well Head - ----12/19/2007 ------------0.47 ------Well Head - ----12/15/2008 ------------<0.5 ------Well Head - ----12/22/2009 ------------0.5 ------Well Head - ----12/27/2012 ------------<0.5 ------Well Head - ND <2 <50-8/20/2013 1600 970 -<5096.8 48.7 170 3.2 160 250 340280 ND <10 210150 420-<5Well Head - ----12/30/2013 ------------<0.5 ------Well Head - ---ND11/20/2014 -------------------Well Head - ----12/29/2015 ------------0.4 ------Well Head - ND <2 <50-8/24/2016 1600 1000 -<5095521603.3 170 240 370300 ND <10 230170 470-<5Well Head - ----7/31/2017 ------------ND ------Well Head - ----7/31/2018 ------------ND ------Well Head - ND ND ND-8/6/2019 -1200 -<50-58 170 3.5 190 300 --<0.4 ND 200170 490-NDWell Head - SANTIAGO ISLAND VILLAGE ----4/28/1998 ----- - - --- --ND ------WELL 01 - ----5/24/2001 ----- - - --- --ND ------WELL 01 - 2.4 7 50-8/1/2002 2000 1300 -<5024 28 430 1.9 160 220 760620 8.6 <10 100<100 <20-<5WELL 01 - ----10/21/2002 ----- - - --- ---------WELL 01 - ----5/28/2003 ----- - - --- --ND ------WELL 01 - ----7/29/2004 ----- - - --- --ND ------WELL 01 - 0.1 <2 50-7/13/2005 1700 1100 -<5050 24 300 2.6 210 320 270220 ND 2.8 100<100 210-<5WELL 01 - ----7/21/2006 ----- - - --- --ND ------WELL 01 - ----7/17/2008 ----- - - --- --ND ------WELL 01 - 0.2 2 <50-4/1/2009 1800 1100 -5043 22 280 2.7 210 280 280230 ND 4.8 <100100 210-<5WELL 01 - ----7/15/2009 ----- - - --- --ND ---190--WELL 01 - ----10/19/2009 ----- - - --- ------180--WELL 01 - ----1/13/2010 ----- - - --- ------180--WELL 01 - ----4/15/2010 ----- - - --- ------200--WELL 01 - 8 ---7/8/2010 ----- - - --- --ND ---180--WELL 01 - ----10/20/2010 ----- - - --- ------190--WELL 01 - ----1/10/2011 ----- - - --- ------160--WELL 01 - ----4/13/2011 ----- - - --- ------190--WELL 01 - ----7/13/2011 ----- - - --- --ND ---200--WELL 01 - ----10/10/2011 ----- - - --- ------200--WELL 01 - ----1/5/2012 ----- - - --- ------200--WELL 01 - Thursday, September 10, 2020Page 67 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer SANTIAGO ISLAND VILLAGE ----4/4/2012 ----------------200--WELL 01 - ND 5 60-5/3/2012 1700 --5043243102.7 210 310 280230 ND 1 <100100 210-<5WELL 01 - 0.2 ---7/12/2012 ----------------190--WELL 01 - 0.2 ---10/17/2012 ----------------180--WELL 01 - 0.12 ---1/15/2013 ----------------200--WELL 01 - ND ---4/8/2013 ------------ND ---190--WELL 01 - ND ---7/16/2013 ----------------180--WELL 01 - ND ---10/7/2013 ----------------180--WELL 01 - ND ---1/9/2014 ----------------180--WELL 01 - ND ---4/9/2014 ----------------180--WELL 01 - ND ---7/15/2014 ----------------190--WELL 01 - ND ---10/22/2014 ----------------190--WELL 01 - ----1/14/2015 ----------------170--WELL 01 - ----4/13/2015 ----------------190--WELL 01 - 0.29 <2 50ND5/13/2015 1700 1000 -<5040 20 300 2.9 190 290 280230 -<10 <100<100 160-<5WELL 01 - ----7/13/2015 ----- - - --- ------170--WELL 01 - ----10/15/2015 ----- - - --- ------200--WELL 01 - ----1/11/2016 ----- - - --- ------160--WELL 01 - ----4/4/2016 ----- - - --- --ND ---170--WELL 01 - ----7/11/2016 ----- - - --- ------170--WELL 01 - ----10/5/2016 ----- - - --- ------160--WELL 01 - ----1/16/2017 ----- - - --- ------160--WELL 01 - ----4/17/2017 ----- - - --- --ND ---180--WELL 01 - ----7/20/2017 ----- - - --- ------190--WELL 01 - ----10/23/2017 ----- - - --- ------160--WELL 01 - ----1/23/2018 ----- - - --- ------170--WELL 01 - ----4/24/2018 ----- - - --- ------190--WELL 01 - ND <2 <50-6/6/2018 1700 1000 -<5040 20 300 2.9 200 300 270220 ND <10 <100<100 190-<5WELL 01 - ----7/16/2018 ----- - - --- ------200--WELL 01 - ----10/8/2018 ----- - - --- ------200--WELL 01 - ----1/9/2019 ----- - - --- ------190--WELL 01 - ----4/2/2019 ----- - - --- ------200--WELL 01 - ----7/10/2019 ----- - - --- ------180--WELL 01 - ----10/8/2019 ----- - - --- ------190--WELL 01 - SUNSET HARBOR ----7/19/2004 ----- - - --- --ND ------Well Head - ----7/20/2005 ----- - - --- --ND ------Well Head - Thursday, September 10, 2020Page 68 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer SUNSET HARBOR ----7/28/2006 ------------ND ------Well Head - ----7/26/2007 ------------ND ------Well Head - ----7/21/2011 ------------ND ------Well Head - ----7/31/2012 ------------ND ------Well Head - ----7/29/2013 ------------ND ------Well Head - ----7/10/2014 ------------ND ------Well Head - ----7/16/2015 ------------ND ------Well Head - ----7/18/2016 ------------ND ------Well Head - ----7/27/2017 ------------ND ------Well Head - ----7/23/2018 ------------ND ------Well Head - ----7/8/2019 ------------ND ------Well Head - TONYS FAMILY RESTAURANT ----6/28/2002 ------------ND ------WELL HEAD - ----6/25/2003 ----- - - --- --ND ------WELL HEAD - ----6/24/2004 ----- - - --- --ND ------WELL HEAD - ----6/29/2006 ----- - - --- --ND ------WELL HEAD - ----6/29/2007 ----- - - --- --ND ------WELL HEAD - ----11/5/2019 ----- - - --- --ND ------WELL HEAD - TUGS ----1/29/2004 ----- - - --- --3.4 ------Well Head - ----1/31/2005 ----- - - --- --ND ------Well Head - ----1/30/2006 ----- - - --- --ND ------Well Head - ----1/29/2007 ----- - - --- --ND ------Well Head - ----1/29/2008 ----- - - --- --ND ------Well Head - ----1/27/2009 ----- - - --- --ND ------Well Head - ----1/28/2010 ----- - - --- --ND ------Well Head - ----1/27/2011 ----- - - --- --ND ------Well Head - ----1/30/2012 ----- - - --- --ND ------Well Head - ----1/31/2013 ----- - - --- --ND ------Well Head - ----1/22/2014 ----- - - --- --ND ------Well Head - ----1/28/2015 ----- - - --- --ND ------Well Head - ----1/27/2016 ----- - - --- --ND ------Well Head - ----2/1/2017 ----- - - --- --ND ------Well Head - ----1/24/2018 ----- - - --- --ND ------Well Head - ----8/1/2018 ----- - - --- --ND ------Well Head - Thursday, September 10, 2020Page 69 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer TUGS ----1/24/2019 ------------ND ------Well Head - VILLA DE GUADALUPE ----4/22/2002 ------------8.8 ------WELL - ----4/1/2003 ------------7.9 ------WELL - ----7/1/2003 ------------8.4 ------WELL - ----10/8/2003 ------------7.9 ------WELL - ----1/6/2004 ------------8.4 ------WELL - ----4/5/2004 ------------7.5 ------WELL - ----7/1/2004 ------------8.1 ------WELL - ----10/4/2004 ------------7.9 ------WELL - ----1/3/2005 ------------7.9 ------WELL - ----4/4/2005 ------------8.6 ------WELL - ----7/6/2005 ------------8.6 ------WELL - ----10/4/2005 ----- - - --- --8.8 ------WELL - ----1/4/2006 ----- - - --- --9.7 ------WELL - 0.4 <2 50-3/2/2006 1400 840 -5080 57 150 1.8 120 140 470390 10 7 100100 <20-<5WELL- ----4/4/2006 ----- - - --- --10 ------WELL - ----7/6/2006 ----- - - --- --11 ------WELL - ----1/19/2007 ----- - - --- --12 ------WELL - ----7/11/2007 ----- - - --- --14 ------WELL - ----10/3/2007 ----- - - --- --13 ------WELL - ----1/3/2008 ----- - - --- --14 ------WELL - ----2/28/2008 ----- - - --- --13 ------WELL - ----3/4/2008 ----- - - --- --13 ------WELL - ----5/1/2008 ----- - - --- --14 ------WELL - ----6/5/2008 ----- - - --- --16 ------WELL - ----7/2/2008 ----- - - --- --15 ------WELL - ----8/5/2008 ----- - - --- --13 ------WELL - ----9/3/2008 ----- - - --- --14 ------WELL - ----10/13/2008 ----- - - --- --13 ------WELL - ----11/19/2008 ----- - - --- --14 ------WELL - ----12/10/2008 ----- - - --- --13 ------WELL - ----1/5/2009 ----- - - --- --13 ------WELL - ----2/2/2009 ----- - - --- --13 ------WELL - 0.5 <2 <50-3/2/2009 1400 900 -5081 57 150 1.8 130 140 460380 13 17 <100100 <20-<5WELL- ----4/1/2009 ----- - - --- --14 ------WELL - ----5/4/2009 ----- - - --- --13 ------WELL - Thursday, September 10, 2020Page 70 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown Aquifer VILLA DE GUADALUPE ----6/1/2009 ------------13 ------WELL - ----7/2/2009 ------------14 ------WELL - ----8/4/2009 ------------13 ------WELL - ----9/3/2009 ------------13 ------WELL - ----10/12/2009 ------------13 ------WELL - ----11/9/2009 ------------14 ------WELL - ----12/7/2009 ------------14 ------WELL - ----1/7/2010 ------------14 ------WELL - ----2/3/2010 ------------14 ------WELL - 0.29 4.5 16-4/15/2010 1470 --23075491407170230211211-1.2 22037 <20-8.2WELL- ----8/30/2017 ------------0.4 ------WELL - WILLOWEST MARINA WS ----12/27/2006 ------------<0.5 ------WELLHEAD - ----12/26/2007 ----- - - --- --<0.5 ------WELLHEAD - ----12/8/2008 ----- - - --- --<0.5 ------WELLHEAD - ----12/30/2009 ----- - - --- --ND ------WELLHEAD - ----12/28/2010 ----- - - --- --<0.5 ------WELLHEAD - ----12/27/2011 ----- - - --- --ND ------WELLHEAD - ----12/20/2012 ----- - - --- --ND ------WELLHEAD - ----12/9/2013 ----- - - --- --ND ------WELLHEAD - ----12/16/2014 ----- - - --- --ND ------WELLHEAD - ----12/16/2015 ----- - - --- --ND ------WELLHEAD - ----12/19/2016 ----- - - --- --0.4 ------WELLHEAD - ----12/13/2017 ----- - - --- --ND ------WELLHEAD - ----12/26/2018 ----- - - --- --ND ------WELLHEAD - ----12/4/2019 ----- - - --- --ND ------WELLHEAD - Thursday, September 10, 2020Page 71 of 72{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Public Supply and Monitoring Wells Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 c) California State Notification Level "-" Not Analyzed; ND = Non-Detect (Reporting Limit unknown) For repeated sampling within a day, the maximum result for each constituent for the day is shown Bold indicates value exceeds Water Quality Limit 1. HCO3 and Total Alkalinity reported as CaCO3; NO3 reported as N a) Primary Drinking Water Standards for California and Federal Maximum Contaminant Levels b) Secondary Drinking Water Standards for California and Federal Maximum Contaminant Levels 2 Samples were filtered in the field Thursday, September 10, 2020Page 72 of 72{R_WaterQualitySummary} 1000 50900 500 10250 2506.5/8.5 10 1000 1000 50 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Surface Water Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO As Cr Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b baaa a aabca 2 --6/23/1994 612 -- - - --------FALSE R NR OAKLEY CA --9/22/1994 991 -- - - --------FALSE R NR OAKLEY CA --12/1/1994 2840 -- - - --------FALSE R NR OAKLEY CA --3/29/1995 336 -- - - --------FALSE R NR OAKLEY CA --5/26/1995 158 -- - - --------FALSE R NR OAKLEY CA --6/26/1996 114 -- - - --------FALSE R NR OAKLEY CA --9/10/2015 --- - - ---0.133 ----HOLLAND CUT NR BETHEL ISLAND CA --9/14/2015 --- - - ---0.138 ----HOLLAND CUT NR BETHEL ISLAND CA --10/21/2015 --- - - ---0.135 ----HOLLAND CUT NR BETHEL ISLAND CA --4/18/2016 --- - - ---0.339 ----HOLLAND CUT NR BETHEL ISLAND CA --7/13/2016 --- - - ---0.04 ----HOLLAND CUT NR BETHEL ISLAND CA --10/3/1960 535 -- - - --98 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --11/7/1960 529 -- - - --82 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --12/12/1960 818 -- - - --155 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --1/9/1961 863 -- - - --156 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --2/13/1961 1040 -- - - --198 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --3/7/1961 1130 -- - - --204 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --4/11/1961 463 -- - - --65 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/2/1961 226 141 - - - --22 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/5/1961 233 -- - - --20 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --7/10/1961 330 -- - - --44 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --8/3/1961 805 -- - - --186 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --9/11/1961 638 332 - - - --132 0.136 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --10/6/1961 452 -- - - --72 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --11/6/1961 459 -- - - --66 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --12/12/1961 799 -- - - --135 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --1/11/1962 1220 -- - - --212 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --2/15/1962 1610 -- - - --326 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --3/8/1962 898 -- - - --158 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --4/11/1962 592 -- - - --88 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/8/1962 304 174 - - - --39 0.226 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/6/1962 415 -- - - --64 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --7/10/1962 231 -- - - --24 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --8/7/1962 293 -- - - --40 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --9/6/1962 336 199 - - - --51 0.294 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --10/4/1962 394 -- - - --61 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --11/13/1962 869 -- - - --154 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --12/10/1962 729 -- - - --125 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --1/7/1963 722 -- - - --134 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --2/6/1963 751 -- - - --127 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --3/13/1963 721 -- - - --123 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --4/10/1963 631 -- - - --100 -----ITALIAN SLOUGH A MOUTH NR BYRON CA Thursday, September 3, 2020Page 1 of 7{R_WaterQualitySummary} 1000 50900 500 10250 2506.5/8.5 10 1000 1000 50 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Surface Water Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO As Cr Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b baaa a aabca 2 --5/2/1963 601 -- - - --113 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/7/1963 506 281 - - - --88 0.113 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/15/1963 371 -- - - --56 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/22/1963 265 -- - - --37 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/29/1963 183 -- - - --24 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/5/1963 153 -- - - --19 0.407 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/12/1963 262 -- - - --38 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/19/1963 243 -- - - --34 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/26/1963 163 -- - - --22 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --7/3/1963 230 -- - - --28 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --7/9/1963 249 -- - - --31 0.497 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --7/17/1963 223 -- - - --24 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --7/24/1963 221 -- - - --22 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --7/31/1963 217 -- - - --22 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --8/6/1963 231 -- - - --23 0.136 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --8/14/1963 243 -- - - --26 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --8/21/1963 262 -- - - --30 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --8/28/1963 273 -- - - --32 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --9/4/1963 281 -- - - --34 0.203 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --9/10/1963 305 171 - - - --34 0.452 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --9/18/1963 311 -- - - --37 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --9/25/1963 380 -- - - --49 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --10/2/1963 405 -- - - --52 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --10/8/1963 342 -- - - --38 0.52 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --10/16/1963 413 -- - - --55 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --10/23/1963 406 -- - - --49 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --10/30/1963 399 -- - - --53 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --11/5/1963 425 -- - - --59 0.813 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --11/14/1963 457 -- - - --66 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --11/20/1963 462 -- - - --71 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --11/27/1963 577 -- - - --103 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --12/3/1963 558 -- - - --99 0.542 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --12/11/1963 554 -- - - --90 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --12/18/1963 591 -- - - --86 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --1/2/1964 573 -- - - --98 1.06 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --1/10/1964 579 -- - - --100 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --1/15/1964 590 -- - - --97 1.49 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --1/23/1964 700 -- - - --109 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --1/29/1964 755 -- - - --124 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --2/4/1964 749 -- - - --123 1.6 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --2/13/1964 792 -- - - --130 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --2/20/1964 798 -- - - --129 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --2/27/1964 844 -- - - --132 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --3/5/1964 631 -- - - --86 -----ITALIAN SLOUGH A MOUTH NR BYRON CA Thursday, September 3, 2020Page 2 of 7{R_WaterQualitySummary} 1000 50900 500 10250 2506.5/8.5 10 1000 1000 50 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Surface Water Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO As Cr Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b baaa a aabca 2 --3/12/1964 463 -- - - --62 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --3/19/1964 398 -- - - --51 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --3/26/1964 390 -- - - --52 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --4/2/1964 438 -- - - --54 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --4/9/1964 386 -- - - --44 0.723 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --4/16/1964 328 -- - - --36 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --4/23/1964 300 -- - - --34 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --4/30/1964 273 -- - - --28 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/7/1964 270 151 - - - --28 0.361 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/14/1964 263 -- - - --28 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/21/1964 250 -- - - --26 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/28/1964 271 -- - - --31 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/4/1964 260 -- - - --27 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/11/1964 342 -- - - --47 0.271 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/18/1964 261 -- - - --23 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/25/1964 252 -- - - --21 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --7/2/1964 248 -- - - --22 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --7/9/1964 269 -- - - --27 0.361 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --8/6/1964 469 240 - - - --88 0.587 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --9/3/1964 541 295 - - - --106 0.384 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --11/5/1964 440 231 - - - --62 0.542 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --12/3/1964 613 309 - - - --92 0.565 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --1/8/1965 751 -- - - --121 1.11 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --2/3/1965 653 -- - - --116 0.858 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --3/3/1965 531 296 - - - --90 0.52 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --4/8/1965 492 -- - - --73 1.17 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --5/6/1965 268 159 - - - --34 0.113 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --6/17/1965 165 86 - - - --22 0.745 ----ITALIAN SLOUGH A MOUTH NR BYRON CA --7/15/1965 253 -- - - --32 -----ITALIAN SLOUGH A MOUTH NR BYRON CA --9/17/1965 345 205 - - - --43 0.881 ----ITALIAN SLOUGH A MOUTH NR BYRON CA <2 <2012/17/2008 -530 53 21 82 4 206 77 0.8 <0.001 290 <10300Marsh Creek <2 <202/17/2009 -260 29 11 47 3 96 34 0.5 <0.001 <50 <10200Marsh Creek 3 <205/12/2009 -770 91 39 114 4 230 129 1.6 3 <50 101000Marsh Creek <2 <208/4/2009 -800 85 37 147 6 260 159 <0.1 <0.001 120 50600Marsh Creek <2 <2011/10/2009 -1690 186 75 259 8 810 240 <0.1 <0.001 <50 20800Marsh Creek <2 <202/25/2010 -530 47 27 82 5 153 71 0.6 <0.001 80 <101300Marsh Creek <2 <205/26/2010 -550 53 20 82 4 169 71 1.1 <0.001 <50 20500Marsh Creek 3 208/12/2010 -670 74 30 116 5 234 107 <0.1 1 <50 150400Marsh Creek 2 <2011/16/2010 -830 78 30 166 12 260 144 3.1 <0.001 <50 140800Marsh Creek <2 <202/24/2011 -580 57 32 81 3 158 81 0.7 <0.001 <50 101700Marsh Creek --10/3/1960 488 -- - - --84 -----OLD R A CLIFTON COURT FERRY CA --11/7/1960 855 -- - - --153 -----OLD R A CLIFTON COURT FERRY CA --12/12/1960 811 -- - - --140 -----OLD R A CLIFTON COURT FERRY CA --1/9/1961 821 -- - - --142 -----OLD R A CLIFTON COURT FERRY CA Thursday, September 3, 2020Page 3 of 7{R_WaterQualitySummary} 1000 50900 500 10250 2506.5/8.5 10 1000 1000 50 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Surface Water Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO As Cr Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b baaa a aabca 2 --2/13/1961 1020 -- - - --178 -----OLD R A CLIFTON COURT FERRY CA --3/7/1961 886 -- - - --136 -----OLD R A CLIFTON COURT FERRY CA --4/11/1961 315 -- - - --39 -----OLD R A CLIFTON COURT FERRY CA --5/2/1961 214 131 - - - --21 0.023 ----OLD R A CLIFTON COURT FERRY CA --6/5/1961 241 -- - - --21 -----OLD R A CLIFTON COURT FERRY CA --7/10/1961 327 -- - - --44 -----OLD R A CLIFTON COURT FERRY CA --8/3/1961 760 -- - - --169 -----OLD R A CLIFTON COURT FERRY CA --9/11/1961 585 312 - - - --120 0.203 ----OLD R A CLIFTON COURT FERRY CA --10/6/1961 430 -- - - --65 -----OLD R A CLIFTON COURT FERRY CA --11/6/1961 914 -- - - --155 -----OLD R A CLIFTON COURT FERRY CA --12/12/1961 1070 -- - - --184 -----OLD R A CLIFTON COURT FERRY CA --1/10/1962 1330 -- - - --236 -----OLD R A CLIFTON COURT FERRY CA --2/15/1962 506 -- - - --73 -----OLD R A CLIFTON COURT FERRY CA --3/8/1962 553 -- - - --73 -----OLD R A CLIFTON COURT FERRY CA --4/11/1962 526 -- - - --76 -----OLD R A CLIFTON COURT FERRY CA --5/8/1962 377 211 - - - --56 0.068 ----OLD R A CLIFTON COURT FERRY CA --6/5/1962 412 -- - - --62 -----OLD R A CLIFTON COURT FERRY CA --7/10/1962 225 -- - - --26 -----OLD R A CLIFTON COURT FERRY CA --8/7/1962 291 -- - - --39 -----OLD R A CLIFTON COURT FERRY CA --9/6/1962 336 198 - - - --50 0.361 ----OLD R A CLIFTON COURT FERRY CA --10/4/1962 387 -- - - --58 -----OLD R A CLIFTON COURT FERRY CA --11/13/1962 768 -- - - --129 -----OLD R A CLIFTON COURT FERRY CA --12/11/1962 464 -- - - --72 -----OLD R A CLIFTON COURT FERRY CA --1/7/1963 611 -- - - --128 -----OLD R A CLIFTON COURT FERRY CA --2/6/1963 189 -- - - --23 -----OLD R A CLIFTON COURT FERRY CA --3/13/1963 614 -- - - --90 -----OLD R A CLIFTON COURT FERRY CA --4/10/1963 299 -- - - --38 -----OLD R A CLIFTON COURT FERRY CA --5/7/1963 249 147 - - - --30 0.181 ----OLD R A CLIFTON COURT FERRY CA --6/5/1963 140 -- - - --16 -----OLD R A CLIFTON COURT FERRY CA --7/9/1963 230 -- - - --27 -----OLD R A CLIFTON COURT FERRY CA --8/7/1963 228 -- - - --22 -----OLD R A CLIFTON COURT FERRY CA --9/10/1963 749 418 - - - --126 0.203 ----OLD R A CLIFTON COURT FERRY CA --10/8/1963 645 -- - - --102 -----OLD R A CLIFTON COURT FERRY CA --11/5/1963 528 -- - - --84 -----OLD R A CLIFTON COURT FERRY CA --12/3/1963 411 -- - - --58 -----OLD R A CLIFTON COURT FERRY CA --1/10/1964 489 -- - - --76 -----OLD R A CLIFTON COURT FERRY CA --2/4/1964 694 -- - - --102 -----OLD R A CLIFTON COURT FERRY CA --3/5/1964 513 -- - - --69 -----OLD R A CLIFTON COURT FERRY CA --4/9/1964 376 -- - - --44 -----OLD R A CLIFTON COURT FERRY CA --5/8/1964 379 208 - - - --53 0.474 ----OLD R A CLIFTON COURT FERRY CA --6/11/1964 257 -- - - --26 -----OLD R A CLIFTON COURT FERRY CA --7/6/1964 359 -- - - --46 -----OLD R A CLIFTON COURT FERRY CA --8/6/1964 427 -- - - --75 -----OLD R A CLIFTON COURT FERRY CA --9/3/1964 826 448 - - - --155 0.497 ----OLD R A CLIFTON COURT FERRY CA Thursday, September 3, 2020Page 4 of 7{R_WaterQualitySummary} 1000 50900 500 10250 2506.5/8.5 10 1000 1000 50 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Surface Water Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO As Cr Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b baaa a aabca 2 --10/8/1964 400 -- - - --50 -----OLD R A CLIFTON COURT FERRY CA --11/11/1964 779 -- - - --126 -----OLD R A CLIFTON COURT FERRY CA --12/10/1964 631 -- - - --96 -----OLD R A CLIFTON COURT FERRY CA --1/7/1965 230 -- - - --24 -----OLD R A CLIFTON COURT FERRY CA --2/3/1965 291 -- - - --36 -----OLD R A CLIFTON COURT FERRY CA --3/4/1965 325 -- - - --46 -----OLD R A CLIFTON COURT FERRY CA --4/8/1965 305 -- - - --43 -----OLD R A CLIFTON COURT FERRY CA --5/6/1965 300 178 - - - --40 0.136 ----OLD R A CLIFTON COURT FERRY CA --6/17/1965 146 -- - - --19 -----OLD R A CLIFTON COURT FERRY CA --7/15/1965 236 -- - - --28 -----OLD R A CLIFTON COURT FERRY CA --8/12/1965 307 -- - - --40 -----OLD R A CLIFTON COURT FERRY CA --9/16/1965 313 183 - - - --36 0.678 ----OLD R A CLIFTON COURT FERRY CA --10/7/1965 418 -- - - --60 -----OLD R A CLIFTON COURT FERRY CA --11/3/1965 411 -- - - --64 -----OLD R A CLIFTON COURT FERRY CA --12/2/1965 320 -- - - --40 -----OLD R A CLIFTON COURT FERRY CA --1/4/1966 215 -- - - --24 -----OLD R A CLIFTON COURT FERRY CA --2/8/1966 552 -- - - --79 -----OLD R A CLIFTON COURT FERRY CA --3/7/1966 583 -- - - --90 -----OLD R A CLIFTON COURT FERRY CA --4/5/1966 505 -- - - --71 -----OLD R A CLIFTON COURT FERRY CA --5/2/1966 328 187 - - - --44 0.316 ----OLD R A CLIFTON COURT FERRY CA --6/7/1966 238 -- - - --22 -----OLD R A CLIFTON COURT FERRY CA --9/18/2017 --- - - ---0.271 ----OLD R A CLIFTON COURT FERRY CA --5/15/2018 --- - - ---0.315 ----OLD R A CLIFTON COURT FERRY CA --7/24/2018 --- - - ---0.081 ----OLD R A CLIFTON COURT FERRY CA --10/19/2018 --- - - ---0.305 ----OLD R A CLIFTON COURT FERRY CA --9/28/1994 694 -- - - --------OLD R A QUIMBY ISLAND NR BETHEL ISLAND CA --11/30/1994 580 -- - - --------OLD R A QUIMBY ISLAND NR BETHEL ISLAND CA --3/29/1995 401 -- - - --------OLD R A QUIMBY ISLAND NR BETHEL ISLAND CA --5/26/1995 162 -- - - --------OLD R A QUIMBY ISLAND NR BETHEL ISLAND CA --6/26/1996 160 -- - - --------OLD R A QUIMBY ISLAND NR BETHEL ISLAND CA --9/10/2015 --- - - ---0.187 ----OLD R A QUIMBY ISLAND NR BETHEL ISLAND CA --9/14/2015 --- - - ---0.172 ----OLD R A QUIMBY ISLAND NR BETHEL ISLAND CA --10/21/2015 --- - - ---0.197 ----OLD R A QUIMBY ISLAND NR BETHEL ISLAND CA --4/18/2016 --- - - ---0.371 ----OLD R A QUIMBY ISLAND NR BETHEL ISLAND CA --7/13/2016 --- - - ---0.05 ----OLD R A QUIMBY ISLAND NR BETHEL ISLAND CA --9/10/2015 --- - - ---0.107 ----OLD RIVER A FAY ISLAND NR MIDDLE RIVER CA --9/14/2015 --- - - ---0.116 ----OLD RIVER A FAY ISLAND NR MIDDLE RIVER CA --10/21/2015 --- - - ---0.158 ----OLD RIVER A FAY ISLAND NR MIDDLE RIVER CA --4/18/2016 --- - - ---0.432 ----OLD RIVER A FAY ISLAND NR MIDDLE RIVER CA --7/13/2016 --- - - ---0.053 ----OLD RIVER A FAY ISLAND NR MIDDLE RIVER CA --10/21/2015 --- - - ---0.407 ----SAN JOAQUIN R A JERSEY ISLAND NR OAKLEY CA --4/18/2016 --- - - ---0.313 ----SAN JOAQUIN R A JERSEY ISLAND NR OAKLEY CA --7/13/2016 --- - - ---0.192 ----SAN JOAQUIN R A JERSEY ISLAND NR OAKLEY CA --9/27/2016 --- - - ---0.198 ----SAN JOAQUIN R A JERSEY POINT CA Thursday, September 3, 2020Page 5 of 7{R_WaterQualitySummary} 1000 50900 500 10250 2506.5/8.5 10 1000 1000 50 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Surface Water Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO As Cr Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b baaa a aabca 2 --10/25/2016 --- - - ---0.335 ----SAN JOAQUIN R A JERSEY POINT CA --11/16/2016 --- - - ---0.475 ----SAN JOAQUIN R A JERSEY POINT CA --12/13/2016 --- - - ---0.462 ----SAN JOAQUIN R A JERSEY POINT CA --3/14/2017 --- - - ---0.344 ----SAN JOAQUIN R A JERSEY POINT CA --4/13/2017 --- - - ---0.199 ----SAN JOAQUIN R A JERSEY POINT CA --5/2/2017 --- - - ---0.11 ----SAN JOAQUIN R A JERSEY POINT CA --5/16/2017 --- - - ---0.12 ----SAN JOAQUIN R A JERSEY POINT CA --6/15/2017 --- - - ---0.146 ----SAN JOAQUIN R A JERSEY POINT CA --7/17/2017 --- - - ---0.039 ----SAN JOAQUIN R A JERSEY POINT CA --7/20/2017 --- - - ---0.037 ----SAN JOAQUIN R A JERSEY POINT CA --8/17/2017 --- - - ---0.182 ----SAN JOAQUIN R A JERSEY POINT CA --9/19/2017 --- - - ---0.202 ----SAN JOAQUIN R A JERSEY POINT CA --9/26/2017 --- - - ---0.164 ----SAN JOAQUIN R A JERSEY POINT CA --10/31/2017 --- - - ---0.259 ----SAN JOAQUIN R A JERSEY POINT CA --11/30/2017 --- - - ---0.455 ----SAN JOAQUIN R A JERSEY POINT CA --12/19/2017 --- - - ---0.46 ----SAN JOAQUIN R A JERSEY POINT CA --1/25/2018 --- - - ---0.619 ----SAN JOAQUIN R A JERSEY POINT CA --2/15/2018 --- - - ---0.549 ----SAN JOAQUIN R A JERSEY POINT CA --3/20/2018 --- - - ---0.509 ----SAN JOAQUIN R A JERSEY POINT CA --3/26/2018 --- - - ---0.387 ----SAN JOAQUIN R A JERSEY POINT CA --4/26/2018 --- - - ---0.27 ----SAN JOAQUIN R A JERSEY POINT CA --5/17/2018 --- - - ---0.269 ----SAN JOAQUIN R A JERSEY POINT CA --6/5/2018 --- - - ---0.251 ----SAN JOAQUIN R A JERSEY POINT CA --7/26/2018 --- - - ---0.114 ----SAN JOAQUIN R A JERSEY POINT CA --9/4/2018 --- - - ---0.176 ----SAN JOAQUIN R A JERSEY POINT CA --10/4/2018 --- - - ---0.192 ----SAN JOAQUIN R A JERSEY POINT CA --10/17/2018 --- - - ---0.26 ----SAN JOAQUIN R A JERSEY POINT CA --11/1/2018 --- - - ---0.28 ----SAN JOAQUIN R A JERSEY POINT CA --1/29/2019 --- - - ---0.694 ----SAN JOAQUIN R A JERSEY POINT CA --3/27/2019 --- - - ---0.36 ----SAN JOAQUIN R A JERSEY POINT CA --4/23/2019 --- - - ---0.147 ----SAN JOAQUIN R A JERSEY POINT CA --3/27/2012 300 -- - - --------SAN JOAQUIN R A KIMBALL ISLAND NR ANTIOCH CA --4/3/2012 235 -- - - --------SAN JOAQUIN R A KIMBALL ISLAND NR ANTIOCH CA --4/10/2012 223 -- - - --------SAN JOAQUIN R A KIMBALL ISLAND NR ANTIOCH CA --4/17/2012 223 -- - - --------SAN JOAQUIN R A KIMBALL ISLAND NR ANTIOCH CA --4/24/2012 221 -- - - --------SAN JOAQUIN R A KIMBALL ISLAND NR ANTIOCH CA --5/1/2012 226 -- - - --------SAN JOAQUIN R A KIMBALL ISLAND NR ANTIOCH CA --5/8/2012 197 -- - - --------SAN JOAQUIN R A KIMBALL ISLAND NR ANTIOCH CA --5/15/2012 217 -- - - --------SAN JOAQUIN R A KIMBALL ISLAND NR ANTIOCH CA --5/22/2012 481 -- - - --------SAN JOAQUIN R A KIMBALL ISLAND NR ANTIOCH CA --5/29/2012 456 -- - - --------SAN JOAQUIN R A KIMBALL ISLAND NR ANTIOCH CA --9/10/2015 --- - - ---0.256 ----SAN JOAQUIN R A TWITCHELL ISLAND NR RIO VISTA CA --10/21/2015 --- - - ---0.413 ----SAN JOAQUIN R A TWITCHELL ISLAND NR RIO VISTA CA --4/18/2016 --- - - ---0.322 ----SAN JOAQUIN R A TWITCHELL ISLAND NR RIO VISTA CA Thursday, September 3, 2020Page 6 of 7{R_WaterQualitySummary} 1000 50900 500 10250 2506.5/8.5 10 1000 1000 50 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Surface Water Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO As Cr Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b baaa a aabca 2 --7/13/2016 --- - - ---0.145 ----SAN JOAQUIN R A TWITCHELL ISLAND NR RIO VISTA CA --9/10/2015 --- - - ---0.274 ----SAN JOAQUIN R AB FALSE NR BETHEL ISLAND CA --10/21/2015 --- - - ---0.391 ----SAN JOAQUIN R AB FALSE NR BETHEL ISLAND CA --4/18/2016 --- - - ---0.32 ----SAN JOAQUIN R AB FALSE NR BETHEL ISLAND CA --7/13/2016 --- - - ---0.185 ----SAN JOAQUIN R AB FALSE NR BETHEL ISLAND CA --9/10/2015 --- - - ---0.254 ----SAN JOAQUIN R BL MOKELUMNE R NR TERMINOUS CA --10/21/2015 --- - - ---0.405 ----SAN JOAQUIN R BL MOKELUMNE R NR TERMINOUS CA --4/18/2016 --- - - ---0.324 ----SAN JOAQUIN R BL MOKELUMNE R NR TERMINOUS CA --7/13/2016 --- - - ---0.125 ----SAN JOAQUIN R BL MOKELUMNE R NR TERMINOUS CA c) California State Notification Level "-" Not Analyzed; ND = Non-Detect (Reporting Limit unknown) For repeated sampling within a day, the maximum result for each constituent for the day is shown Bold indicates value exceeds Water Quality Limit 1. HCO3 and Total Alkalinity reported as CaCO3; NO3 reported as N a) Primary Drinking Water Standards for California and Federal Maximum Contaminant Levels b) Secondary Drinking Water Standards for California and Federal Maximum Contaminant Levels 2 Samples were filtered in the field Thursday, September 3, 2020Page 7 of 7{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----8/9/1973 1080 612 7.8 -68 34 108 0.3 97 139 -228 3.6 ----160001N03E17E001M -- -1 1.2-6/24/1975 1200 -8.2 -- -118 --160 -259 --0.09-1-01N03E17E001M -- ----7/20/1977 1270 -8 -- -113 --216 -240 ------01N03E17E001M -- ----8/3/1979 1360 -8.4 -94 44 121 --227 -233 ------01N03E17E001M -- ----8/3/1981 1220 -7.9 -87 39 114 --184 -238 ------01N03E17E001M -- ----8/16/1983 1210 730 8 -82 38 116 0.8 102 185 -239 -----150001N03E17E001M -- ----8/1/1985 1270 -8.7 -90 40 113 --191 -230 ------01N03E17E001M -- ----7/28/1987 1300 -8.1 -95 52 123 --209 -245 ------01N03E17E001M -- ----9/14/1989 1400 -8.2 -97 47 128 0.4 -218 -258 ------01N03E17E001M -- ----10/13/1978 --6.5 -- - - --104 --0.07 ----50001S04E09N001M -- ----4/8/1981 ----- - - --- -------50001S04E09N001M -- ----7/30/2009 --7.18 -- - - -2.1 - --------SL0601346154-94MW-2 -- ----7/30/2009 --7.85 -- - - -100 - --------SL0601346154-94MW-25 -- ----7/30/2009 --7.26 -- - - -92 - --------SL0601346154-94MW-3 -- ----7/30/2009 --9.04 -- - - -110 - --------SL0601346154-94SP-4 -- 0.33 2.63 -ND7/12/2013 -1200 --98.8 75.6 119 1.28 330 140 --4.3 <0.01 50.5-1730-SL186102968-7EW-1 NDND 0.5 2.58 -ND7/12/2013 -1360 --115 77.5 134 1.36 520 150 --4.7 <0.01 53.6-208-SL186102968-7EW-2 NDND ND ND --8/21/2013 -7960 --597 381 661 5.04 1500 120 --5.2 -ND-277-SL186102968-7EW-2 3.45- 0.34 14.3 --9/17/2013 -925 --70.5 45.6 123 2.1 290 81 --ND -1270-1790-SL186102968-7EW-2 ND- 0.31 4.76 -ND7/12/2013 -740 --65.2 40.5 74.2 3.48 150 86 --0.18 <0.01 ND-839-SL186102968-7EW-4 NDND ND 1.25 --8/21/2013 -3480 --564 402 1060 8.84 2400 79 --1.1 -ND-1930-SL186102968-7EW-4 5.09- ND ND --9/17/2013 -10100 --850 624 2580 14.2 4000 65 --5.1 -ND-2530-SL186102968-7EW-4 8.06- 0.17 5.43 --10/22/2013 -815 --72.2 35.9 108 6.9 290 61 --ND -515-3260-SL186102968-7EW-4 1.56- 0.24 3.38 --11/19/2013 -1160 --103 52.3 136 9.16 410 62 --ND -243-4150-SL186102968-7EW-4 ND- 0.14 2.5 --12/17/2013 -1040 --76.8 40.9 117 8.05 280 64 --0.42 -2070-4610-SL186102968-7EW-4 ND- 0.27 5.3 --1/21/2014 -1020 --94.8 57.2 149 4.09 310 120 --16 -ND-2.09-SL186102968-7EW-4 ND- 0.25 3.02 --2/18/2014 -3120 --250 157 497 15.2 2200 77 --ND -57.7-7980-SL186102968-7EW-4 1.83- 0.26 ---3/19/2014 ----- - - -4100 69 --0.94 -----SL186102968-7EW-4 -- 0.34 6.58 -ND7/12/2013 -1110 --62.7 38.5 93.4 152 170 98 --ND <0.01 6250-591-SL186102968-7EW-6 NDND 0.37 4.89 --8/21/2013 -645 --39.3 19.7 71.4 87.6 100 59 --ND -1070-1130-SL186102968-7EW-6 ND- 0.45 4.22 --9/17/2013 -590 --34 17.3 63.6 57.6 71 47 --ND -575-1060-SL186102968-7EW-6 ND- ----10/22/2013 ----- - - -44 - --------SL186102968-7EW-6 -- ---1.64/12/2013 -400 --- - - -88 - ---2 ----SL186102968-7MW-1 -1.6 ---ND5/28/2013 -925 --- - - -280 - ---29.5 ----SL186102968-7MW-1 -ND 0.21 5.4 -ND7/12/2013 -1230 --102 60.6 148 4.81 300 97 --7.2 -ND-85.4-SL186102968-7MW-1 1.19ND 0.16 5.45 -ND8/21/2013 -915 --85.6 49.8 134 4.98 320 110 --2.8 <0.01 ND-68.1-SL186102968-7MW-1 NDND Thursday, September 3, 2020Page 1 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow 0.15 3.65 -ND9/17/2013 -995 --88.8 47.5 137 4.91 310 110 --0.95 -ND-7.74-SL186102968-7MW-1 NDND ND 4.81 -ND10/22/2013 -995 --86.9 47.8 139 4.92 310 120 --2.5 <0.001 ND-81.1-SL186102968-7MW-1 1.44ND 0.16 4.61 -ND11/19/2013 -950 --90.5 54.7 134 4.05 300 120 --4.2 <0.001 ND-47.3-SL186102968-7MW-1 NDND 0.14 4.78 -ND12/17/2013 -840 --79.5 50.7 128 4.2 220 91 --13 <0.001 ND-39.9-SL186102968-7MW-1 6.33ND 0.23 4.17 -ND1/21/2014 -835 --86.2 49.7 104 4.46 210 90 --12 <0.001 ND-51.6-SL186102968-7MW-1 4.26ND 0.17 3.97 -ND2/18/2014 -825 --88.1 50 91.4 5.22 210 88 --12 <0.001 ND-61.8-SL186102968-7MW-1 4.05ND ---ND3/19/2014 ----- - - --- --------SL186102968-7MW-1 -ND ---ND5/27/2014 -705 --- - - -160 - ---<0.001 ----SL186102968-7MW-1 -ND ---ND8/19/2014 -819 --- - - -220 - ---<0.16 ----SL186102968-7MW-1 -ND ---ND12/9/2014 -610 --- - - -131 - ---<0.21 ----SL186102968-7MW-1 -ND ----3/10/2015 -293 --- - - -68.3 - ---2.7 ----SL186102968-7MW-1 -- ----6/9/2015 -420 --- - - -108 - ---1.7 ----SL186102968-7MW-1 -- ---1.56/16/2015 ----- - - --- --------SL186102968-7MW-1 -1.5 ---ND8/11/2015 -660 --- - - -188 - ---<1 ----SL186102968-7MW-1 -ND ----5/9/2007 ----- - - --- --1.8 -----SL186102968-7MW-10 -- ----8/3/2007 ----- - - --- --1.4 -----SL186102968-7MW-10 -- ---4.94/12/2013 -605 --- - - -110 - ---5.98 ----SL186102968-7MW-10 -4.9 ---5.15/28/2013 -820 --- - - -150 - ---5.43 ----SL186102968-7MW-10 -5.1 ---8.83/10/2015 -504 --- - - -81.3 - ---7.4 ----SL186102968-7MW-10 -8.8 ----6/9/2015 -376 --- - - -40.5 - ---6.8 ----SL186102968-7MW-10 -- ---6.76/16/2015 ----- - - --- --------SL186102968-7MW-10 -6.7 ----7/28/2009 ----- - - --- ---<0.005 ----SL186102968-7MW-11 -- ---ND4/12/2013 -1460 --- - - -550 - --------SL186102968-7MW-11 -ND ---ND5/28/2013 -1640 --- - - -600 - ---<0.001 ----SL186102968-7MW-11 -ND 0.34 2.77 -ND7/12/2013 -1620 --124 101 208 1.82 580 190 --9.7 <0.01 ND-5.39-SL186102968-7MW-11 NDND 0.33 3.46 -ND8/21/2013 -1560 --106 81.5 210 1.94 510 190 --9.1 <0.01 ND-3.49-SL186102968-7MW-11 NDND 0.36 2.61 -ND9/17/2013 -1420 --107 86.7 221 1.81 470 160 --9.3 1.71 ND-4.97-SL186102968-7MW-11 NDND 0.21 3.1 -ND10/22/2013 -1060 --79.7 61.3 205 2 330 120 --3.2 1.05 ND-63.8-SL186102968-7MW-11 NDND 0.31 3.8 -ND11/19/2013 -1120 --80.1 65.4 178 1.95 360 110 --7.2 <0.001 ND-18.6-SL186102968-7MW-11 1.01ND 0.3 2.55 -ND12/17/2013 -735 --41.4 35.5 131 1.41 220 92 --6.7 1.18 ND-6.24-SL186102968-7MW-11 NDND 0.35 2.58 -ND1/21/2014 -1000 --76.6 62.2 184 1.77 400 130 --7.3 <0.001 ND-19-SL186102968-7MW-11 NDND 0.3 1.52 -ND2/18/2014 -295 --29.7 22.7 68.1 1.66 130 47 --4.1 <0.001 ND-4.47-SL186102968-7MW-11 NDND ---ND3/19/2014 ----- - - --- --------SL186102968-7MW-11 -ND ---ND5/27/2014 -870 --- - - -240 - --------SL186102968-7MW-11 -ND ---ND8/19/2014 -1100 --- - - -376 - --------SL186102968-7MW-11 -ND ---ND12/9/2014 -1160 --- - - -374 - ---<0.52 ----SL186102968-7MW-11 -ND ----3/10/2015 -1150 --- - - -425 - ---<0.81 ----SL186102968-7MW-11 -- ----6/9/2015 -1010 --- - - -383 - ---<0.28 ----SL186102968-7MW-11 -- ---ND6/16/2015 ----- - - --- --------SL186102968-7MW-11 -ND ---0.28/11/2015 -1320 --- - - -456 - ---<1 ----SL186102968-7MW-11 -0.2 ----7/28/2009 ----- - - --- ---<0.005 ----SL186102968-7MW-12 -- Thursday, September 3, 2020Page 2 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow 0.54 4.89 -1.67/12/2013 -590 --42.8 32.3 103 0.794 110 39 --11 <0.01 ND-5.38-SL186102968-7MW-12 ND1.6 0.54 5.34 -1.68/21/2013 -570 --36.3 26.6 88.4 0.967 110 36 --11 <0.01 ND-2.42-SL186102968-7MW-12 ND1.6 0.52 4.88 -1.69/17/2013 -655 --39.7 30.2 101 0.993 130 42 --12 2.13 ND-2.62-SL186102968-7MW-12 ND1.6 0.38 6.68 -1.710/22/2013 -625 --40 28.5 105 1.15 120 38 --12 1.49 ND-4.23-SL186102968-7MW-12 ND1.7 0.47 7.05 -1.511/19/2013 -670 --41.2 30.9 98.1 1.03 130 36 --13 2.35 ND-7.05-SL186102968-7MW-12 ND1.5 0.5 5.8 -1.312/17/2013 -715 --40.3 31.2 124 1.02 140 47 --12 1.98 ND-7.95-SL186102968-7MW-12 ND1.3 0.57 5.42 -1.61/21/2014 -630 --43.3 32.3 109 1.06 150 44 --13 -ND-5.25-SL186102968-7MW-12 ND1.6 0.61 4.08 -1.32/18/2014 -655 --47.5 33.7 98.1 1.09 160 49 --12 1.78 ND-5.84-SL186102968-7MW-12 ND1.3 ---1.13/19/2014 ----- - - --- --------SL186102968-7MW-12 -1.1 ---2.65/27/2014 -845 --- - - -200 - ---3.01 ----SL186102968-7MW-12 -2.6 ---2.68/19/2014 -591 --- - - -120 - ---2 ----SL186102968-7MW-12 -2.6 ---2.512/9/2014 -622 --- - - -136 - ---2.1 ----SL186102968-7MW-12 -2.5 ----3/10/2015 -567 --- - - -114 - ---2.8 ----SL186102968-7MW-12 -- ----6/9/2015 -544 --- - - -99.3 - ---2.5 ----SL186102968-7MW-12 -- ---2.36/16/2015 ----- - - --- --------SL186102968-7MW-12 -2.3 ---2.28/11/2015 -613 --- - - -120 - ---2.3 ----SL186102968-7MW-12 -2.2 ----5/9/2007 ----- - - --- --7.1 -----SL186102968-7MW-13 -- ----8/3/2007 ----- - - --- --8.9 -----SL186102968-7MW-13 -- ----7/28/2009 ----- - - --- ---<0.005 ----SL186102968-7MW-13 -- 0.5 4.78 -2.37/12/2013 -800 --61.3 43.1 107 1.28 210 93 --9.9 <0.01 ND-2.65-SL186102968-7MW-13 ND2.3 0.56 6.2 -1.88/21/2013 -830 --64.3 42.2 131 1.15 250 94 --11 <0.01 ND-1.99-SL186102968-7MW-13 ND1.8 0.52 4.24 -1.89/17/2013 -860 --64.9 42.3 129 1.45 240 98 --9.5 -ND-2.6-SL186102968-7MW-13 ND1.8 0.28 6.02 -2.110/22/2013 -910 --67.4 42.6 135 1.76 210 110 --9.1 -ND-1.96-SL186102968-7MW-13 ND2.1 0.45 6.9 -211/19/2013 -865 --70.9 48.3 131 1.33 240 110 --9.9 3 ND-1.62-SL186102968-7MW-13 1.132 0.46 5.62 -1.712/17/2013 -880 --63.6 46.1 152 1.2 250 100 --10 21.6 ND-1.68-SL186102968-7MW-13 ND1.7 0.48 4.88 -1.71/21/2014 -885 --73.4 50.1 150 1.29 250 100 --9.7 2.67 ND-2.22-SL186102968-7MW-13 ND1.7 0.47 5.2 -2.42/18/2014 -845 --75 49.8 124 1.76 230 95 --9.2 3.15 ND-1.64-SL186102968-7MW-13 ND2.4 ---23/19/2014 ----- - - --- --------SL186102968-7MW-13 -2 ---1.85/27/2014 -635 --- - - -150 - ---1.81 ----SL186102968-7MW-13 -1.8 ---2.18/19/2014 -864 --- - - -236 - ---1.6 ----SL186102968-7MW-13 -2.1 ---1.512/9/2014 -919 --- - - -262 - ---1.3 ----SL186102968-7MW-13 -1.5 ----3/10/2015 -864 --- - - -228 - --------SL186102968-7MW-13 -- ----6/9/2015 -169 --- - - -218 - ---1.3 ----SL186102968-7MW-13 -- ---1.56/16/2015 ----- - - --- --------SL186102968-7MW-13 -1.5 ---1.68/11/2015 -882 --- - - -220 - ---1.1 ----SL186102968-7MW-13 -1.6 ----5/9/2007 ----- - - --- --0.68 -----SL186102968-7MW-14 -- ----8/3/2007 ----- - - --- --0.1 -----SL186102968-7MW-14 -- 0.17 ND -ND7/12/2013 -375 --28.6 14.9 39.3 4.02 18 36 --ND -900-695-SL186102968-7MW-14 NDND ND 1.14 --8/21/2013 -450 --42.6 18.4 61.6 5.31 77 37 --2.5 -256-820-SL186102968-7MW-14 ND- ND 1.33 --9/17/2013 -595 --72.1 30 81.2 6.49 130 85 --2.5 -952-1590-SL186102968-7MW-14 ND- ND 1.55 --10/22/2013 -805 --86.4 35.5 102 8.14 190 97 --2.9 -2120-2020-SL186102968-7MW-14 ND- ND ND --11/19/2013 -1220 --143 65.1 129 9.57 500 100 --1 -3250-3350-SL186102968-7MW-14 ND- Thursday, September 3, 2020Page 3 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ND 5.47 --12/17/2013 -1490 --142 76.6 125 10.1 690 77 --0.89 -31800-7100-SL186102968-7MW-14 ND- ND 2.08 --1/21/2014 -870 --72.1 34.2 113 7.14 340 66 --2.1 -13000-3110-SL186102968-7MW-14 ND- ND ND --2/18/2014 -980 --88.1 41.3 117 8.8 420 61 --2.8 -11200-2660-SL186102968-7MW-14 ND- 0.12 ---3/19/2014 ----- - - -410 52 --1.7 -----SL186102968-7MW-14 -- ----5/9/2007 ----- - - --- --0.1 -----SL186102968-7MW-2 -- ----8/3/2007 ----- - - --- --0.1 -----SL186102968-7MW-2 -- ----7/29/2009 ----- - - --- ---<0.005 ----SL186102968-7MW-2 -- 0.33 2.93 -ND7/12/2013 -795 --98.6 51.4 67.7 2.99 10 45 --ND -192-6950-SL186102968-7MW-2 NDND ----10/22/2013 ----- - - -550 - --------SL186102968-7MW-2 -- ----12/17/2013 ----- - - --- ---4.23 ----SL186102968-7MW-2 -- ----7/28/2009 ----- - - --- ---<0.005 ----SL186102968-7MW-3 -- 0.65 2.92 -ND7/12/2013 -910 --79.2 61.7 110 0.875 180 85 --ND <0.01 102-1790-SL186102968-7MW-3 NDND ----5/9/2007 ----- - - --- --0.1 -----SL186102968-7MW-4 -- ----8/3/2007 ----- - - --- --0.11 -----SL186102968-7MW-4 -- ----5/9/2007 ----- - - --- --1.5 -----SL186102968-7MW-5 -- ----8/3/2007 ----- - - --- --0.18 -----SL186102968-7MW-5 -- ----7/29/2009 ----- - - --- ---<0.005 ----SL186102968-7MW-5 -- 0.59 2.82 -ND7/12/2013 -340 --32.5 15.5 15.6 6.08 80 11 --5.7 <0.01 567-2880-SL186102968-7MW-5 NDND ----10/22/2013 ----- - - -120 - --------SL186102968-7MW-5 -- ----7/28/2009 ----- - - --- ---<0.005 ----SL186102968-7MW-6 -- ND --1.64/12/2013 -940 --- - - -310 140 --13 -----SL186102968-7MW-6 -1.6 ---1.35/28/2013 -1060 --- - - -310 - --------SL186102968-7MW-6 -1.3 0.24 4.09 -1.17/12/2013 -1090 --89.1 60.7 130 2.89 260 110 --11 -ND-3.78-SL186102968-7MW-6 4.361.1 0.24 4.23 -ND8/21/2013 -800 --63 41.3 121 2.52 150 110 --6.1 <0.01 ND-ND-SL186102968-7MW-6 NDND 0.32 2.79 -ND9/17/2013 -935 --70.9 47.6 133 2.45 170 180 --1.8 1.62 ND-3.67-SL186102968-7MW-6 NDND 0.15 4.58 -ND10/22/2013 -805 --65.4 41.8 123 2.34 130 140 --1.1 1.06 ND-ND-SL186102968-7MW-6 NDND 0.25 4.39 -ND11/19/2013 -590 --61.4 40.7 95.4 2.11 110 100 --1.3 1.29 ND-ND-SL186102968-7MW-6 NDND 0.2 4.61 -ND12/17/2013 -685 --45 32.4 98 1.86 120 76 --1.2 1.51 ND-ND-SL186102968-7MW-6 NDND 0.29 4.45 -ND1/21/2014 -530 --40.2 26.8 84.5 1.78 120 71 --1.2 2.7 ND-ND-SL186102968-7MW-6 NDND 0.28 4.48 -ND2/18/2014 -500 --41.2 27.2 74.6 2.16 99 72 --0.97 1.27 ND-ND-SL186102968-7MW-6 NDND ---ND3/19/2014 ----- - - --- --------SL186102968-7MW-6 -ND ---ND5/27/2014 -620 --- - - -100 - ---1.09 ----SL186102968-7MW-6 -ND ---0.598/19/2014 -782 --- - - -197 - --------SL186102968-7MW-6 -0.59 ---ND12/9/2014 -848 --- - - -181 - ---<0.68 ----SL186102968-7MW-6 -ND ----3/10/2015 -503 --- - - -106 - --------SL186102968-7MW-6 -- ----6/9/2015 -412 --- - - -76.6 - --------SL186102968-7MW-6 -- ---ND6/16/2015 ----- - - --- --------SL186102968-7MW-6 -ND ---1.48/11/2015 -249 --- - - -37.5 - ---1.5 ----SL186102968-7MW-6 -1.4 ----5/9/2007 ----- - - --- --8.7 -----SL186102968-7MW-7 -- ----8/3/2007 ----- - - --- --10 -----SL186102968-7MW-7 -- Thursday, September 3, 2020Page 4 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----5/9/2007 ----- - - --- --4.7 -----SL186102968-7MW-8 -- ----8/3/2007 ----- - - --- --5 -----SL186102968-7MW-8 -- ----7/28/2009 ----- - - --- ---<0.005 ----SL186102968-7MW-8 -- ---ND4/12/2013 -1100 --- - - -200 - ---<0.001 ----SL186102968-7MW-8 -ND ---ND5/28/2013 -1160 --- - - -220 - ---<0.001 ----SL186102968-7MW-8 -ND 0.36 4.13 -ND7/12/2013 -1060 --128 78 131 1.51 170 91 --ND <0.01 ND-1410-SL186102968-7MW-8 NDND 0.37 3.21 -ND8/21/2013 -1080 --104 62 117 1.49 250 100 --0.12 <0.01 ND-943-SL186102968-7MW-8 NDND 0.41 2.49 -ND9/17/2013 -1280 --123 73.9 152 1.62 410 150 --ND <0.001 ND-767-SL186102968-7MW-8 NDND 0.24 4.01 -ND10/22/2013 -1350 --120 70.3 160 1.7 390 150 --ND -ND-1040-SL186102968-7MW-8 NDND 0.35 3.76 -ND11/19/2013 -1280 --136 81.8 150 1.79 490 160 --ND -ND-762-SL186102968-7MW-8 NDND 0.35 3.69 -ND12/17/2013 -1340 --128 84.1 174 1.94 440 150 --ND <0.001 ND-1030-SL186102968-7MW-8 NDND 0.43 3.4 -ND1/21/2014 -1300 --118 70.7 141 1.52 410 140 --ND <0.001 ND-1220-SL186102968-7MW-8 NDND 0.4 2.89 -ND2/18/2014 -1300 --140 83.9 144 2.1 450 150 --ND -ND-450-SL186102968-7MW-8 NDND 0.36 --ND3/19/2014 -1100 --- - - -400 130 --ND <0.001 ----SL186102968-7MW-8 -ND ---ND4/21/2014 -1140 --- - - -310 - ---<0.001 ----SL186102968-7MW-8 -ND ---ND5/27/2014 -875 --- - - -170 - --------SL186102968-7MW-8 -ND ---ND6/17/2014 -960 --- - - -290 - --------SL186102968-7MW-8 -ND ---2.57/22/2014 -1200 --- - - -394 - --------SL186102968-7MW-8 -2.5 ---ND8/19/2014 -1260 --- - - -424 - ---<0.26 ----SL186102968-7MW-8 -ND ---ND9/11/2014 -1520 --- - - -447 - --------SL186102968-7MW-8 -ND ---ND10/14/2014 -1420 --- - - -529 - ---<0.5 ----SL186102968-7MW-8 -ND ---ND11/11/2014 -1460 --- - - -512 - ---<0.2 ----SL186102968-7MW-8 -ND ---ND12/9/2014 -1510 --- - - -556 - ---<0.17 ----SL186102968-7MW-8 -ND ---1.11/6/2015 -1290 --- - - -413 - ---1.4 ----SL186102968-7MW-8 -1.1 ---42/3/2015 -875 --- - - -230 - ---3.4 ----SL186102968-7MW-8 -4 ---2.82/11/2015 ----- - - --- --------SL186102968-7MW-8 -2.8 ----3/10/2015 -1140 --- - - -343 - ---1.6 ----SL186102968-7MW-8 -- ---1.94/7/2015 -1170 --- - - -362 - ---1.4 ----SL186102968-7MW-8 -1.9 ---1.55/5/2015 -1080 --- - - -317 - ---1.5 ----SL186102968-7MW-8 -1.5 ----6/9/2015 -1130 --- - - -360 - ---1.6 ----SL186102968-7MW-8 -- ---ND6/16/2015 ----- - - --- --------SL186102968-7MW-8 -ND ---1.38/11/2015 -1080 --- - - -314 - ---1.2 ----SL186102968-7MW-8 -1.3 ---ND11/9/2015 -1210 --- - - -435 - ---<0.13 ----SL186102968-7MW-8 -ND ----5/9/2007 ----- - - --- --10 -----SL186102968-7MW-9 -- ----8/3/2007 ----- - - --- --11 -----SL186102968-7MW-9 -- ----7/28/2009 ----- - - --- ---<0.005 ----SL186102968-7MW-9 -- ---4.84/12/2013 -815 --- - - -170 - ---6.16 ----SL186102968-7MW-9 -4.8 ---5.75/28/2013 -870 --- - - -160 - ---5.64 ----SL186102968-7MW-9 -5.7 0.74 6.19 -5.37/12/2013 -815 --54.8 43.5 122 0.8 110 89 --8.4 <0.01 ND-7.6-SL186102968-7MW-9 ND5.3 0.42 6.48 -6.58/21/2013 -755 --47.2 35.6 116 0.883 120 74 --9.9 <0.01 ND-9.64-SL186102968-7MW-9 ND6.5 0.57 5.11 -7.49/17/2013 -775 --50.6 41 129 0.959 120 71 --8.6 9.94 ND-9.44-SL186102968-7MW-9 ND7.4 0.33 6.94 -6.510/22/2013 -745 --53 39.7 146 1.05 110 76 --8 7.1 ND-9.55-SL186102968-7MW-9 ND6.5 Thursday, September 3, 2020Page 5 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow 0.36 6.66 -511/19/2013 -740 --54.6 41.6 123 1 130 82 --7.6 6.19 ND-7.63-SL186102968-7MW-9 ND5 0.37 5.98 -5.712/17/2013 -805 --55.6 47.6 143 1.16 130 92 --9 6.59 ND-12.4-SL186102968-7MW-9 ND5.7 0.54 5.26 -5.71/21/2014 -840 --58.5 45.6 136 0.971 150 95 --9.4 6.06 ND-23.3-SL186102968-7MW-9 ND5.7 0.44 5.68 -5.12/18/2014 -830 --61.8 48.1 116 1.13 140 94 --11 -ND-19.7-SL186102968-7MW-9 ND5.1 ---4.43/19/2014 ----- - - --- --------SL186102968-7MW-9 -4.4 ---5.35/27/2014 -975 --- - - -150 - ---6.31 ----SL186102968-7MW-9 -5.3 ---7.88/19/2014 -1100 --- - - -202 - --------SL186102968-7MW-9 -7.8 ---4.212/9/2014 -1020 --- - - -193 - ---4.5 ----SL186102968-7MW-9 -4.2 ---3.73/10/2015 -1060 --- - - -193 - ---3.3 ----SL186102968-7MW-9 -3.7 ----6/9/2015 -1160 --- - - -193 - --------SL186102968-7MW-9 -- ---5.66/16/2015 ----- - - --- --------SL186102968-7MW-9 -5.6 ---6.68/11/2015 -1200 --- - - -211 - ---7.7 ----SL186102968-7MW-9 -6.6 ----5/5/2005 ----- - - -240 200 --------SL205032990-GCC-1 -- ----5/5/2005 ----- - - -210 88 --------SL205032990-GCC-2 -- ----5/5/2005 ----- - - -130 200 --------SL205032990-GCC-3 -- ----5/5/2005 ----- - - -190 230 --------SL205032990-GCC-4 -- -10 --2/11/2005 ----- - - -750 130 ----ND-ND-SL205032990-GPG-1 -- -8.3 --2/11/2005 ----- - - -620 140 ---<10 ND-ND-SL205032990-GPG-2 -- -ND --2/10/2005 ----- - - -930 52 ---<10 ND-620-SL205032990-W-01 -- -ND --6/29/2006 ----- - - -900 42 ---11 ND-840-SL205032990-W-01 -- -ND --5/21/2007 ----- - - -850 33 --11 9.2 ND-520-SL205032990-W-01 -- -7.2 --5/28/2008 ----- - - -780 30 --11 13 ND-860-SL205032990-W-01 -- -6.8 --2/11/2005 ----- - - -1400 240 ---<10 600-30-SL205032990-W-02 -- -7.7 --6/30/2006 ----- - - -1100 200 ---<10 ND-19-SL205032990-W-02 -- ----12/1/2006 ----- - - --- --------SL205032990-W-02 -- -ND --5/21/2007 ----- - - -740 150 --43 <5 ND-18-SL205032990-W-02 -- ----12/20/2007 ----- - - --- --------SL205032990-W-02 -- -8.1 --5/28/2008 ----- - - -470 200 --22 -ND-20-SL205032990-W-02 -- ----12/30/2008 ----- - - --- --------SL205032990-W-02 -- ----6/4/2009 ----- - - --- --------SL205032990-W-02 -- ----12/7/2009 ----- - - --- --------SL205032990-W-02 -- ----5/27/2010 ----- - - --- --------SL205032990-W-02 -- ----11/4/2010 ----- - - --- --------SL205032990-W-02 -- ----5/26/2011 ----- - - --- --------SL205032990-W-02 -- ----11/3/2011 ----- - - --- --------SL205032990-W-02 -- -6.9 --2/11/2005 ----- - - -190 91 ---<10 ND-ND-SL205032990-W-03 -- -ND --8/3/2005 ----- - - --- ---<10 ND-ND-SL205032990-W-03 -- -6.4 --6/30/2006 ----- - - -180 82 ---<10 ND-ND-SL205032990-W-03 -- Thursday, September 3, 2020Page 6 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow -ND --5/22/2007 ----- - - -210 74 --2 <5 ND-ND-SL205032990-W-03 -- -11 --5/28/2008 ----- - - -220 64 --1.5 <5 ND-ND-SL205032990-W-03 -- -8.5 --2/10/2005 ----- - - -890 300 --32 <10 ND-110-SL205032990-W-04 -- -6.4 --6/29/2006 ----- - - -1600 170 ----ND-110-SL205032990-W-04 -- ----12/1/2006 ----- - - --- --------SL205032990-W-04 -- -ND --5/21/2007 ----- - - -38000 3500 --1400 14 ND-110-SL205032990-W-04 -- ----12/20/2007 ----- - - --- --------SL205032990-W-04 -- -25 --5/28/2008 ----- - - -1300 100 --47 5.4 ND-420-SL205032990-W-04 -- ----12/30/2008 ----- - - --- --------SL205032990-W-04 -- ----6/4/2009 ----- - - --- --------SL205032990-W-04 -- ----12/7/2009 ----- - - --- --------SL205032990-W-04 -- ----5/27/2010 ----- - - --- --------SL205032990-W-04 -- ----11/4/2010 ----- - - --- --------SL205032990-W-04 -- ----5/25/2011 ----- - - --- --------SL205032990-W-04 -- ----11/3/2011 ----- - - --- --------SL205032990-W-04 -- ----12/20/2018 ----- - - -2200 - --185 25 --5300-SL205032990-W-04 -- ----6/21/2019 ----110 130 140 14 2100 70 --106 -----SL205032990-W-04 -- ----9/30/2019 -2400 --130 130 - -1800 66 --165 -----SL205032990-W-04 -- -ND --2/10/2005 ----- - - -1700 260 --14 <10 620-9600-SL205032990-W-05 -- -ND --8/3/2005 ----- - - --- ----260-9700-SL205032990-W-05 -- -20 --6/29/2006 ----- - - -2100 230 ---<10 1000-13000-SL205032990-W-05 -- ----12/1/2006 ----- - - --- --------SL205032990-W-05 -- -ND --5/21/2007 ----- - - -3100 210 --67 -1400-12000-SL205032990-W-05 -- ----12/20/2007 ----- - - --- --------SL205032990-W-05 -- -28 --5/28/2008 ----- - - -2200 180 --58 5.5 1800-7800-SL205032990-W-05 -- ----12/30/2008 ----- - - --- --------SL205032990-W-05 -- ----6/4/2009 ----- - - --- --------SL205032990-W-05 -- ----12/7/2009 ----- - - --- --------SL205032990-W-05 -- ----5/27/2010 ----- - - --- --------SL205032990-W-05 -- ----11/4/2010 ----- - - --- --------SL205032990-W-05 -- ----5/25/2011 ----- - - --- --------SL205032990-W-05 -- ----11/3/2011 ----- - - --- --------SL205032990-W-05 -- ----12/20/2018 ----- - - --160 ---4.1 2300-2300-SL205032990-W-05 -- ----6/21/2019 -1400 --47 25 110 14 1800 160 --88.1 -<1---SL205032990-W-05 -- ----9/30/2019 ----31 18 110 9.3 -160 --61 -----SL205032990-W-05 -- -ND --2/10/2005 ----- - - -320 220 --18 <10 ND-450-SL205032990-W-06 -- -ND --8/3/2005 ----- - - --- --6.9 -110-320-SL205032990-W-06 -- -ND --6/29/2006 ----- - - -270 290 ---<10 ND-300-SL205032990-W-06 -- ----12/1/2006 ----- - - --- --------SL205032990-W-06 -- -ND --5/21/2007 ----- - - -380 230 --45 <5 ND-340-SL205032990-W-06 -- ----12/20/2007 ----- - - --- --------SL205032990-W-06 -- Thursday, September 3, 2020Page 7 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow -ND --5/28/2008 ----- - - -430 120 --30 <5 ND-360-SL205032990-W-06 -- ----12/30/2008 ----- - - --- --------SL205032990-W-06 -- ----6/4/2009 ----- - - --- --------SL205032990-W-06 -- ----12/7/2009 ----- - - --- --------SL205032990-W-06 -- ----5/27/2010 ----- - - --- --------SL205032990-W-06 -- ----11/4/2010 ----- - - --- --------SL205032990-W-06 -- ----5/26/2011 ----- - - --- --------SL205032990-W-06 -- ----11/3/2011 ----- - - --- --------SL205032990-W-06 -- -12 --2/10/2005 ----- - - -1800 200 --21 <10 ND-6400-SL205032990-W-07 -- -8.4 --8/3/2005 ----- - - --- --12 -ND-7200-SL205032990-W-07 -- -7.2 --6/30/2006 ----- - - -1600 190 ---<10 ND-7900-SL205032990-W-07 -- ----12/1/2006 ----- - - --- --------SL205032990-W-07 -- -ND --5/21/2007 ----- - - -1200 230 --16 5.4 ND-9600-SL205032990-W-07 -- ----12/20/2007 ----- - - --- --------SL205032990-W-07 -- -9.6 --5/28/2008 ----- - - -600 220 --20 <5 ND-4200-SL205032990-W-07 -- ----12/30/2008 ----- - - --- --------SL205032990-W-07 -- ----6/4/2009 ----- - - --- --------SL205032990-W-07 -- ----12/7/2009 ----- - - --- --------SL205032990-W-07 -- ----6/24/2010 ----- - - --- --------SL205032990-W-07 -- ----11/4/2010 ----- - - --- --------SL205032990-W-07 -- ----5/26/2011 ----- - - --- --------SL205032990-W-07 -- ----11/3/2011 ----- - - --- --------SL205032990-W-07 -- ----12/20/2018 ----- - - --230 ---<0.01 --6800-SL205032990-W-07 -- ----6/21/2019 ----- 43 - -880 210 --21 -<1---SL205032990-W-07 -- ----9/30/2019 ----43 46 150 7.4 780 200 --19 -----SL205032990-W-07 -- -ND --6/29/2006 ----- - - -640 260 ----ND-8900-SL205032990-W-08 -- ----5/27/2010 ----- - - --- --------SL205032990-W-08 -- -9.2 --2/11/2005 ----- - - -100 16 ----ND-ND-SL205032990-W-09 -- -ND --2/10/2005 ----- - - -570 160 --26 -ND-940-SL205032990-W-10 -- -ND --8/3/2005 ----- - - --- --22 -4400-770-SL205032990-W-10 -- -ND --6/29/2006 ----- - - -640 220 ---<10 ND-960-SL205032990-W-10 -- ----12/1/2006 ----- - - --- --------SL205032990-W-10 -- -ND --5/21/2007 ----- - - -620 200 --23 <5 160-1100-SL205032990-W-10 -- ----12/21/2007 ----- - - --- --------SL205032990-W-10 -- -ND --5/28/2008 ----- - - -580 200 --23 <5 ND-1200-SL205032990-W-10 -- ----12/30/2008 ----- - - --- --------SL205032990-W-10 -- ----6/3/2009 ----- - - --- --------SL205032990-W-10 -- ----12/8/2009 ----- - - --- --------SL205032990-W-10 -- ----5/27/2010 ----- - - --- --------SL205032990-W-10 -- ----11/4/2010 ----- - - --- --------SL205032990-W-10 -- ----5/26/2011 ----- - - --- --------SL205032990-W-10 -- Thursday, September 3, 2020Page 8 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----11/3/2011 ----- - - --- --------SL205032990-W-10 -- -ND --2/11/2005 ----- - - -1600 270 ---<10 ND-4400-SL205032990-W-12 -- -ND --5/22/2007 ----- - - -1500 230 --22 <5 ND-3700-SL205032990-W-12 -- -20 --5/28/2008 ----- - - -1300 200 --18 <5 470-3400-SL205032990-W-12 -- ----12/30/2008 ----- - - --- --------SL205032990-W-12 -- ----6/3/2009 ----- - - --- --------SL205032990-W-12 -- ----12/8/2009 ----- - - --- --------SL205032990-W-12 -- ----5/26/2010 ----- - - --- --------SL205032990-W-12 -- ----11/4/2010 ----- - - --- --------SL205032990-W-12 -- ----5/26/2011 ----- - - --- --------SL205032990-W-12 -- ----11/3/2011 ----- - - --- --------SL205032990-W-12 -- ----2/11/2005 ----- - - -1100 1300 --------SL205032990-W-13 -- -10 --6/30/2006 ----- - - -1100 1100 ---<10 ND-1700-SL205032990-W-13 -- -ND --5/22/2007 ----- - - -1600 300 --6.8 <5 ND-3800-SL205032990-W-13 -- -7.4 --5/28/2008 ----- - - -1400 300 --14 <5 ND-2800-SL205032990-W-13 -- ----2/14/2005 ----- - - -210 300 --------SL205032990-W-16 -- ----2/11/2005 ----- - - -1100 200 --------SL205032990-W-18 -- -ND --2/10/2005 ----- - - -1400 270 --7.4 <10 ND-9100-SL205032990-W-19 -- ----8/3/2005 ----- - - --- --11 -----SL205032990-W-19 -- -5.9 --6/30/2006 ----- - - -310 57 ---<10 190-1500-SL205032990-W-19 -- -ND --5/22/2007 ----- - - -1100 200 --14 <5 ND-8900-SL205032990-W-19 -- -8.7 --5/28/2008 ----- - - -440 110 --2.1 <5 6200-5600-SL205032990-W-19 -- -ND --2/11/2005 ----- - - -180 130 ---<10 ND-970-SL205032990-W-20 -- -ND --6/30/2006 ----- - - -230 84 ---<10 ND-920-SL205032990-W-20 -- -ND --5/22/2007 ----- - - -220 79 --5.3 <5 2100-780-SL205032990-W-20 -- -ND --5/29/2008 ----- - - -170 78 --2.7 <5 2700-650-SL205032990-W-20 -- -9.4 --2/11/2005 ----- - - -310 310 ---<10 ND-250-SL205032990-W-21 -- -9.1 --2/11/2005 ----- - - -170 70 ---<10 ND-ND-SL205032990-W-22 -- -ND --6/29/2006 ----- - - -110 73 ---21 ND-ND-SL205032990-W-22 -- -ND --2/11/2005 ----- - - -490 350 ---12 2100-3300-SL205032990-W-23 -- -ND --6/29/2006 ----- - - -170 220 ---12 ND-630-SL205032990-W-23 -- -ND --5/22/2007 ----- - - -200 220 --6.5 -310-750-SL205032990-W-23 -- -ND --5/29/2008 ----- - - -190 240 --5 10 140-650-SL205032990-W-23 -- -ND --2/14/2005 ----- - - -1100 410 ---<10 100-5000-SL205032990-W-24 -- -ND --6/29/2006 ----- - - -820 310 ---<10 690-5600-SL205032990-W-24 -- ----12/1/2006 ----- - - --- --------SL205032990-W-24 -- -ND --5/22/2007 ----- - - -680 340 --2.1 <5 3300-6900-SL205032990-W-24 -- ----12/21/2007 ----- - - --- --------SL205032990-W-24 -- Thursday, September 3, 2020Page 9 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow -ND --5/29/2008 ----- - - -680 280 --3.1 -110-3900-SL205032990-W-24 -- ----12/30/2008 ----- - - --- --------SL205032990-W-24 -- ----6/3/2009 ----- - - --- --------SL205032990-W-24 -- ----12/8/2009 ----- - - --- --------SL205032990-W-24 -- ----5/26/2010 ----- - - --- --------SL205032990-W-24 -- ----11/4/2010 ----- - - --- --------SL205032990-W-24 -- ----5/25/2011 ----- - - --- --------SL205032990-W-24 -- ----11/3/2011 ----- - - --- --------SL205032990-W-24 -- ----2/11/2005 ----- - - -140 350 --------SL205032990-W-25 -- -6.5 --2/10/2005 ----- - - -180 270 --7.6 <10 ND-ND-SL205032990-W-26 -- -8.3 --6/30/2006 ----- - - -230 300 ---<10 ND-400-SL205032990-W-26 -- -ND --5/22/2007 ----- - - -230 300 --3.7 <5 ND-360-SL205032990-W-26 -- ----2/11/2005 ----- - - -570 190 --------SL205032990-W-27 -- -ND --6/30/2006 ----- - - -230 180 ---<10 ND-760-SL205032990-W-27 -- ----12/1/2006 ----- - - --- --------SL205032990-W-27 -- -ND --5/22/2007 ----- - - -300 140 --8.4 <5 ND-840-SL205032990-W-27 -- ----12/21/2007 ----- - - --- --------SL205032990-W-27 -- -ND --5/29/2008 ----- - - -260 140 --6.2 <5 ND-610-SL205032990-W-27 -- -ND --2/14/2005 ----- - - -8800 310 ---29 290-4000-SL205032990-W-28 -- -ND --8/3/2005 ----- - - --- ---110 7800-3400-SL205032990-W-28 -- -ND --6/29/2006 ----- - - -580 200 ---11 110-1100-SL205032990-W-28 -- ----12/1/2006 ----- - - --- --------SL205032990-W-28 -- -ND --5/22/2007 ----- - - -620 170 --12 15 340-1200-SL205032990-W-28 -- ----12/21/2007 ----- - - --- --------SL205032990-W-28 -- -ND --5/29/2008 ----- - - -430 140 --6.6 9.3 1200-1800-SL205032990-W-28 -- ----12/30/2008 ----- - - --- --------SL205032990-W-28 -- ----6/4/2009 ----- - - --- --------SL205032990-W-28 -- ----12/8/2009 ----- - - --- --------SL205032990-W-28 -- ----5/26/2010 ----- - - --- --------SL205032990-W-28 -- ----11/4/2010 ----- - - --- --------SL205032990-W-28 -- ----5/25/2011 ----- - - --- --------SL205032990-W-28 -- ----11/3/2011 ----- - - --- --------SL205032990-W-28 -- ----12/20/2018 ----- - - -420 280 --1.5 40 3900---SL205032990-W-28 -- ----6/21/2019 -770 --17 15 160 1.3 180 - --17 -<1---SL205032990-W-28 -- ----9/30/2019 -1100 --52 30 200 2.1 640 280 --1.1 -----SL205032990-W-28 -- ----2/11/2005 ----- - - -87 220 --------SL205032990-W-29 -- -ND --2/11/2005 ----- - - -200 390 ---<10 ND-820-SL205032990-W-30 -- -6.3 --2/11/2005 ----- - - -580 53 ---<10 ND-ND-SL205032990-W-31 -- ----6/30/2006 ----- - - -590 - --------SL205032990-W-31 -- Thursday, September 3, 2020Page 10 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----5/23/2007 ----- - - -600 - --------SL205032990-W-31 -- ----5/29/2008 ----- - - -600 - --------SL205032990-W-31 -- -ND --2/14/2005 ----- - - -1700 290 ---<10 ND-2800-SL205032990-W-32 -- ----6/30/2006 ----- - - -1300 - ------5300-SL205032990-W-32 -- ----5/22/2007 ----- - - -1200 - ------5100-SL205032990-W-32 -- ----5/29/2008 ----- - - -960 - ------5400-SL205032990-W-32 -- ----2/14/2005 ----- - - -730 260 --------SL205032990-W-33 -- -9.9 --2/14/2005 ----- - - -380 350 ----ND-ND-SL205032990-W-34 -- -5.4 --8/3/2005 ----- - - --- ---11 ND-ND-SL205032990-W-34 -- -ND --6/29/2006 ----- - - -480 480 ---<10 ND-ND-SL205032990-W-34 -- ----12/1/2006 ----- - - --- --------SL205032990-W-34 -- -5.8 --5/22/2007 ----- - - -770 520 --91 -ND-ND-SL205032990-W-34 -- ----12/20/2007 ----- - - --- --------SL205032990-W-34 -- -5.9 --5/29/2008 ----- - - -700 390 --91 14 ND-ND-SL205032990-W-34 -- -8.4 --2/11/2005 ----- - - -240 240 ----ND-ND-SL205032990-W-35 -- -11 --2/11/2005 ----- - - -660 190 ---<10 ND-2800-SL205032990-W-36 -- -ND --6/29/2006 ----- - - -630 180 ----ND-3700-SL205032990-W-36 -- ----12/1/2006 ----- - - --- --------SL205032990-W-36 -- -ND --5/22/2007 ----- - - -650 200 --23 -ND-2700-SL205032990-W-36 -- ----12/21/2007 ----- - - --- --------SL205032990-W-36 -- -5.1 --5/29/2008 ----- - - -630 210 --23 -ND-2300-SL205032990-W-36 -- -ND --2/14/2005 ----- - - -900 62 ---<10 110-4200-SL205032990-W-37 -- -ND --6/30/2006 ----- - - -910 52 ---<10 ND-6900-SL205032990-W-37 -- ----12/1/2006 ----- - - --- --------SL205032990-W-37 -- -ND --5/22/2007 ----- - - -450 130 --16 <5 ND-1400-SL205032990-W-37 -- ----12/20/2007 ----- - - --- --------SL205032990-W-37 -- -ND --5/29/2008 ----- - - -610 21 --1.2 -1800-2300-SL205032990-W-37 -- ----12/29/2008 ----- - - --- --------SL205032990-W-37 -- ----6/3/2009 ----- - - --- --------SL205032990-W-37 -- ----12/7/2009 ----- - - --- --------SL205032990-W-37 -- ----5/26/2010 ----- - - --- --------SL205032990-W-37 -- ----11/4/2010 ----- - - --- --------SL205032990-W-37 -- ----5/25/2011 ----- - - --- --------SL205032990-W-37 -- ----11/3/2011 ----- - - --- --------SL205032990-W-37 -- ----2/14/2005 ----- - - -460 130 --------SL205032990-W-38 -- -ND --2/11/2005 ----- - - -540 270 ---<10 430-1300-SL205032990-W-40 -- -6.8 --6/30/2006 ----- - - -270 210 ---<10 360-3300-SL205032990-W-40 -- ----12/1/2006 ----- - - --- --------SL205032990-W-40 -- -ND --5/22/2007 ----- - - -120 150 --29 <5 190-520-SL205032990-W-40 -- Thursday, September 3, 2020Page 11 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----12/21/2007 ----- - - --- --------SL205032990-W-40 -- -10 --5/29/2008 ----- - - -100 170 --29 9.4 1800-260-SL205032990-W-40 -- ----11/22/2005 ----- - - -240 - --0.24 -11000-690-SL205092993-MW-11A -- ----12/5/2006 ----- - - -120 - --0.2 -ND-700-SL205092993-MW-11A -- ----12/3/2007 ----- - - -300 - --0.3 -2540-863-SL205092993-MW-11A -- ----12/1/2016 ----- - - -95 - --ND -4670-758-SL205092993-MW-11A -- ----12/5/2006 ----- - - -150 - --0.36 -1400-140-SL205092993-MW-12A -- ----12/1/2016 ----- - - -100 - --0.59 -944-84-SL205092993-MW-12A -- ----8/16/2005 ----- - - -260 - -650 6.7 -16000-510-SL205092993-MW-14A -- ----11/22/2005 ----- - - -360 - --4.5 -ND-280-SL205092993-MW-14A -- ----5/31/2006 ----- - - -360 - --3.1 -1100-370-SL205092993-MW-14A -- ----12/5/2006 ----- - - -230 - --9 -1300-ND-SL205092993-MW-14A -- ----6/22/2007 ----- - - -430 - --4.7 -2900-7.5-SL205092993-MW-14A -- ----12/3/2007 ----- - - -820 - --0.79 -30400-1350-SL205092993-MW-14A -- ----5/28/2009 ----- - - -570 - --2.9 -107-815-SL205092993-MW-14A -- ----6/9/2016 ----- - - -590 - --9.4 -1030-577-SL205092993-MW-14A -- ----12/1/2016 ----- - - -800 - --7.2 -ND-623-SL205092993-MW-14A -- ----12/1/2016 ----- - - -140 - --1.5 -933-17-SL205092993-MW-17A -- ----8/16/2005 ----- - - -120 - -250 ND -1400-160-SL205092993-MW-18A -- ----11/22/2005 ----- - - -130 - --1.9 -ND-41-SL205092993-MW-18A -- ----5/31/2006 ----- - - -120 - --2.9 -2200-ND-SL205092993-MW-18A -- ----12/5/2006 ----- - - -310 - --5 -ND-74-SL205092993-MW-18A -- ----6/22/2007 ----- - - -180 - --1.8 -100-156-SL205092993-MW-18A -- ----12/3/2007 ----- - - -200 - --3.1 -214-69-SL205092993-MW-18A -- ----11/22/2005 ----- - - -ND - --ND -88000-690-SL205092993-MW-3A -- ----12/5/2006 ----- - - -0.97 - --ND -53000-510-SL205092993-MW-3A -- ----12/4/2007 ----- - - -1.3 - --0.1 -53700-366-SL205092993-MW-3A -- ----12/1/2016 ----- - - -ND - --ND -26100-142-SL205092993-MW-3A -- ----8/16/2005 ----- - - -ND - -550 ND -62000-560-SL205092993-MW-5A -- ----11/22/2005 ----- - - -220 - --ND -59000-720-SL205092993-MW-5A -- ----5/31/2006 ----- - - -ND - --ND -19000-260-SL205092993-MW-5A -- ----12/5/2006 ----- - - -ND - --ND -ND-420-SL205092993-MW-5A -- ----6/22/2007 ----- - - -1.9 - --0.1 -34300-310-SL205092993-MW-5A -- ----12/4/2007 ----- - - -1.7 - --0.1 -26100-312-SL205092993-MW-5A -- ----5/28/2009 ----- - - -13 - --ND -26400-299-SL205092993-MW-5A -- ----6/9/2016 ----- - - -ND - --ND -19300-142-SL205092993-MW-5A -- ----12/1/2016 ----- - - -ND - --ND -26300-165-SL205092993-MW-5A -- ----11/22/2005 ----- - - -25 - --ND -300-150-SL205092993-MW-5B -- ----12/5/2006 ----- - - -28 - --ND -ND-120-SL205092993-MW-5B -- Thursday, September 3, 2020Page 12 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----12/3/2007 ----- - - -580 - --0.2 -1900-725-SL205092993-MW-5B -- ----12/1/2016 ----- - - -130 - --15 -ND-26.7-SL205092993-MW-5B -- ----11/22/2005 ----- - - -200 - --ND -15000-6600-SL205092993-MW-6A -- ----12/5/2006 ----- - - -270 - --ND -3400-1700-SL205092993-MW-6A -- ----12/3/2007 ----- - - -280 - --0.1 -2020-5240-SL205092993-MW-6A -- ----12/1/2016 ----- - - -99 - --ND -1810-2960-SL205092993-MW-6A -- ----8/16/2005 ----- - - -88 - -230 2.8 -3200-3300-SL205092993-MW-8A -- ----11/22/2005 ----- - - -110 - --0.45 -2900-5500-SL205092993-MW-8A -- ----5/31/2006 ----- - - -140 - --ND -ND-8700-SL205092993-MW-8A -- ----12/5/2006 ----- - - -150 - --0.2 -780-2000-SL205092993-MW-8A -- ----6/22/2007 ----- - - -160 - --0.2 -15100-6500-SL205092993-MW-8A -- ----12/3/2007 ----- - - -170 - --0.2 -5710-7280-SL205092993-MW-8A -- ----5/28/2009 ----- - - -120 - --ND -1980-5450-SL205092993-MW-8A -- ----6/9/2016 ----- - - -60 - --ND -2580-2320-SL205092993-MW-8A -- ----12/1/2016 ----- - - -55 - --ND -4570-1990-SL205092993-MW-8A -- ----3/22/2006 -1000 --- - - -180 - --0.155871 -2900---SL205383009-ORC-7 -- ----3/12/2008 -1000 --- - - -230 - --1.4 -5500---SL205383009-ORC-7 -- ----3/12/2008 -890 --- - - -93 - --ND -4600---SL205383009-ORC-8 -- ----3/12/2008 -1000 --- - - -180 - --0.34 -39000---SL205383009-ORC-9A -- ----3/22/2006 -920 --- - - -98 - --ND -7200---SL205383009-SB-56 -- ----3/12/2008 -980 --- - - -170 - --0.58 -7100---SL205383009-SB-56 -- ----3/12/2008 -1000 --- - - -190 - --0.98 -15000---SL205383009-SB-57 -- ----3/22/2006 -1000 --- - - -120 - --ND -32000---SL205383009-SB-81A -- ----3/12/2008 -950 --- - - -200 - --0.59 -150000---SL205383009-SB-81A -- ----3/12/2008 -1000 --- - - -170 - --1.1 -10000---SL205383009-SB-83A -- ---ND6/15/2011 ----- - - --- --------T0601300676-MW-16A -ND ---ND10/31/2011 ----- - - --- --------T0601300676-MW-16A -ND ---ND6/12/2012 ----- - - --- --------T0601300676-MW-16A -ND ---ND5/30/2013 ----- - - --- --------T0601300676-MW-16A -ND ---ND11/6/2013 ----- - - --- --------T0601300676-MW-16A -ND ---ND5/7/2014 ----- - - --- --------T0601300676-MW-16A -ND ---ND11/21/2014 ----- - - --- --------T0601300676-MW-16A -ND ---ND5/6/2015 ----- - - --- --------T0601300676-MW-16A -ND ---ND11/17/2015 ----- - - --- --------T0601300676-MW-16A -ND ---ND5/26/2016 ----- - - --- --------T0601300676-MW-16A -ND -190 580ND11/9/2016 ----- - - --- ---170 -1800 --T0601300676-MW-16A NDND ---ND11/17/2017 ----- - - --- --------T0601300676-MW-16A -ND ---<55/11/2018 ----- - - --- ---20 ----T0601300676-MW-16A -<5 Thursday, September 3, 2020Page 13 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ---<0.412/6/2018 ----- - - --- ---3.1 ----T0601300676-MW-16A -<0.4 ---<0.22/27/2019 ----- - - --- ---370 ----T0601300676-MW-16A -<0.2 ---<0.23/14/2019 ----- - - --- ---81 ----T0601300676-MW-16A -<0.2 ---<0.26/6/2019 ----- - - --- --------T0601300676-MW-16A -<0.2 ---<0.210/28/2019 ----- - - --- ---4.2 ----T0601300676-MW-16A -<0.2 ---ND6/15/2011 ----- - - --- --------T0601300676-MW-16B -ND ---ND10/31/2011 ----- - - --- --------T0601300676-MW-16B -ND ---ND6/12/2012 ----- - - --- --------T0601300676-MW-16B -ND ---ND5/30/2013 ----- - - --- --------T0601300676-MW-16B -ND ---7.611/6/2013 ----- - - --- --------T0601300676-MW-16B -7.6 ---1.55/7/2014 ----- - - --- --------T0601300676-MW-16B -1.5 ---ND11/21/2014 ----- - - --- --------T0601300676-MW-16B -ND ---ND5/6/2015 ----- - - --- --------T0601300676-MW-16B -ND ---811/17/2015 ----- - - --- --------T0601300676-MW-16B -8 ---ND5/26/2016 ----- - - --- --------T0601300676-MW-16B -ND ---1.911/21/2014 ----- - - --- --------T0601300676-MW-16C -1.9 ---7.65/6/2015 ----- - - --- --------T0601300676-MW-16C -7.6 ---611/17/2015 ----- - - --- --------T0601300676-MW-16C -6 ---5.45/26/2016 ----- - - --- --------T0601300676-MW-16C -5.4 -ND NDND11/5/2007 ----- - - -120 - --ND -1400350 --T0601300676-MW-17 NDND -62 1100ND12/3/2007 ----- - - -130 - --ND 710 1200003400 --T0601300676-MW-17 18ND -8.5 NDND1/15/2008 ----- - - -130 - --ND <5 1200260 --T0601300676-MW-17 NDND ---ND6/14/2011 ----- - - --- --------T0601300676-MW-17 -ND ---ND10/31/2011 ----- - - --- --------T0601300676-MW-17 -ND ---ND6/12/2012 ----- - - --- --------T0601300676-MW-17 -ND ---ND5/30/2013 ----- - - --- --------T0601300676-MW-17 -ND ---ND11/6/2013 ----- - - --- --------T0601300676-MW-17 -ND ---ND5/7/2014 ----- - - --- --------T0601300676-MW-17 -ND ---ND11/21/2014 ----- - - --- --------T0601300676-MW-17 -ND ---ND5/6/2015 ----- - - --- --------T0601300676-MW-17 -ND ---ND11/17/2015 ----- - - --- --------T0601300676-MW-17 -ND ---ND5/25/2016 ----- - - --- --------T0601300676-MW-17 -ND -9.1 NDND11/9/2016 ----- - - --- ---<5 -370 --T0601300676-MW-17 NDND -12 470ND11/8/2016 ----- - - --- ---42 -260 --T0601300676-MW-22 NDND ---ND11/15/2017 ----- - - --- ---2.3 ----T0601300676-MW-22 -ND ----5/10/2018 ----- - - --- ---13 ----T0601300676-MW-22 -- ---<0.212/5/2018 ----- - - --- ---47 ----T0601300676-MW-22 -<0.2 ---<0.26/6/2019 ----- - - --- ---64 ----T0601300676-MW-22 -<0.2 ---<0.210/29/2019 ----- - - --- ---100 ----T0601300676-MW-22 -<0.2 -ND NDND11/5/2007 ----- - - -54 - --3.3 <5 ND370 --T0601300676-MW-25B NDND Thursday, September 3, 2020Page 14 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow -7.8 NDND12/3/2007 ----- - - -94 - --6.6 47 ND540 --T0601300676-MW-25B 11ND -ND ND2.61/15/2008 ----- - - -100 - --7.6 12 830400 --T0601300676-MW-25B 8.52.6 -ND ND1011/5/2007 ----- - - -190 - --6.8 15 ND83 --T0601300676-MW-26 710 -6 NDND12/3/2007 ----- - - -150 - --5.5 -2500150 --T0601300676-MW-26 12ND -6.8 ND9.81/15/2008 ----- - - -210 - --8 9.8 71059 --T0601300676-MW-26 109.8 ---1011/17/2017 ----- - - --- --------T0601300676-MW-26 -10 ---115/11/2018 ----- - - --- --------T0601300676-MW-26 -11 ----12/4/2018 ----- - - --- ---19 ----T0601300676-MW-26 -- ---<0.210/28/2019 ----- - - --- ---9.3 ----T0601300676-MW-26 -<0.2 -5.5 -ND5/29/2007 ---5200140 53 -3.9 67 - --ND -3300280 2000-T0601300676-MW-26B -ND -ND NDND11/5/2007 ----- - - -49 - --0.83 14 550360 --T0601300676-MW-26B NDND -7.5 NDND12/3/2007 ----- - - -58 - --1.9 -13000410 --T0601300676-MW-26B 8.7ND -5.9 NDND1/15/2008 ----- - - -60 - --ND <5 3200310 --T0601300676-MW-26B 5.4ND ---ND6/14/2011 ----- - - --- --------T0601300676-MW-26B -ND ---ND10/31/2011 ----- - - --- --------T0601300676-MW-26B -ND ---ND6/12/2012 ----- - - --- --------T0601300676-MW-26B -ND ---ND5/30/2013 ----- - - --- --------T0601300676-MW-26B -ND ---ND11/6/2013 ----- - - --- --------T0601300676-MW-26B -ND ---ND5/7/2014 ----- - - --- --------T0601300676-MW-26B -ND ---ND11/21/2014 ----- - - --- --------T0601300676-MW-26B -ND ---ND5/6/2015 ----- - - --- --------T0601300676-MW-26B -ND ---ND11/17/2015 ----- - - --- --------T0601300676-MW-26B -ND ---ND5/25/2016 ----- - - --- --------T0601300676-MW-26B -ND -ND 1206.811/8/2016 ----- - - --- ---12 -240 --T0601300676-MW-28 ND6.8 ---ND5/22/2017 ----- - - --- --------T0601300676-MW-28 -ND ---4.211/17/2017 ----- - - --- --------T0601300676-MW-28 -4.2 ----5/10/2018 ----- - - --- ---43 ----T0601300676-MW-28 -- ---7.112/5/2018 ----- - - --- ---29 ----T0601300676-MW-28 -7.1 ---7.86/6/2019 ----- - - --- --------T0601300676-MW-28 -7.8 ----10/29/2019 ----- - - --- ---2.7 ----T0601300676-MW-28 -- -ND 200ND11/8/2016 ----- - - --- -----730 --T0601300676-MW-30A NDND ---ND11/15/2017 ----- - - --- ---<1 ----T0601300676-MW-30A -ND ---<0.55/10/2018 ----- - - --- ---1 ----T0601300676-MW-30A -<0.5 ---<0.212/5/2018 ----- - - --- ---2.1 ----T0601300676-MW-30A -<0.2 ----6/6/2019 ----- - - --- ---<0.5 ----T0601300676-MW-30A -- ---<0.210/29/2019 ----- - - --- ---3.8 ----T0601300676-MW-30A -<0.2 -16 85ND11/9/2016 ----- - - --- ---26 -1500 --T0601300676-MW-31A NDND ---ND11/17/2017 ----- - - --- --------T0601300676-MW-31A -ND ---<15/11/2018 ----- - - --- ---110 ----T0601300676-MW-31A -<1 ---<0.212/4/2018 ----- - - --- ---56 ----T0601300676-MW-31A -<0.2 Thursday, September 3, 2020Page 15 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----1/25/2019 ----- - - --- ---12 ----T0601300676-MW-31A -- ---<0.22/27/2019 ----- - - --- ---9.2 ----T0601300676-MW-31A -<0.2 ---<0.23/14/2019 ----- - - --- ---5.1 ----T0601300676-MW-31A -<0.2 ---<0.26/6/2019 ----- - - --- ---<5 ----T0601300676-MW-31A -<0.2 ---<0.210/28/2019 ----- - - --- ---1.3 ----T0601300676-MW-31A -<0.2 -100 -ND5/29/2007 ---16000180 76 -5.6 98 - --ND 42 90000570 2800-T0601300676-MW-5A -ND -46 NDND11/5/2007 ----- - - -170 - --ND <5 ND370 --T0601300676-MW-5A NDND -270 NDND12/3/2007 ----- - - -120 - --ND 98 260000840 --T0601300676-MW-5A NDND -38 NDND1/15/2008 ----- - - -120 - --ND <5 16000380 --T0601300676-MW-5A NDND ---ND6/14/2011 ----- - - --- --------T0601300676-MW-5A -ND ---ND10/31/2011 ----- - - --- --------T0601300676-MW-5A -ND ---ND6/12/2012 ----- - - --- --------T0601300676-MW-5A -ND ---ND5/30/2013 ----- - - --- --------T0601300676-MW-5A -ND ---ND11/6/2013 ----- - - --- --------T0601300676-MW-5A -ND ---ND5/7/2014 ----- - - --- --------T0601300676-MW-5A -ND ---ND11/21/2014 ----- - - --- --------T0601300676-MW-5A -ND ---ND5/6/2015 ----- - - --- --------T0601300676-MW-5A -ND ---ND11/17/2015 ----- - - --- --------T0601300676-MW-5A -ND ---ND5/24/2016 ----- - - --- --------T0601300676-MW-5A -ND -750 390ND11/9/2016 ----- - - --- ---620 -4900 --T0601300676-MW-5A 11ND ---ND11/17/2017 ----- - - --- --------T0601300676-MW-5A -ND ---<0.55/11/2018 ----- - - --- ---170 ----T0601300676-MW-5A -<0.5 ----12/6/2018 ----- - - --- ---41 ----T0601300676-MW-5A -- ---<0.21/25/2019 ----- - - --- ---370 ----T0601300676-MW-5A -<0.2 ---2702/27/2019 ----- - - --- --------T0601300676-MW-5A -270 ---<0.23/14/2019 ----- - - --- --------T0601300676-MW-5A -<0.2 ---<0.26/6/2019 ----- - - --- ---3.1 ----T0601300676-MW-5A -<0.2 ---<0.210/28/2019 ----- - - --- ---13 ----T0601300676-MW-5A -<0.2 -41 -ND5/29/2007 ----220 97 -5.1 17 - --ND 28 25000660 3800-T0601300676-MW-5B -ND -29 NDND11/5/2007 ----- - - -17 - --ND -ND330 --T0601300676-MW-5B NDND -35 NDND12/3/2007 ----- - - -29 - --ND 33 22000680 --T0601300676-MW-5B NDND -35 NDND1/15/2008 ----- - - -34 - --ND 17 16000640 --T0601300676-MW-5B 5.5ND ---ND6/14/2011 ----- - - --- --------T0601300676-MW-5B -ND ---ND10/31/2011 ----- - - --- --------T0601300676-MW-5B -ND ---ND6/12/2012 ----- - - --- --------T0601300676-MW-5B -ND ---ND5/30/2013 ----- - - --- --------T0601300676-MW-5B -ND ---ND11/6/2013 ----- - - --- --------T0601300676-MW-5B -ND ---ND5/7/2014 ----- - - --- --------T0601300676-MW-5B -ND ---ND11/21/2014 ----- - - --- --------T0601300676-MW-5B -ND ---ND5/6/2015 ----- - - --- --------T0601300676-MW-5B -ND ---ND11/17/2015 ----- - - --- --------T0601300676-MW-5B -ND ---ND5/24/2016 ----- - - --- --------T0601300676-MW-5B -ND Thursday, September 3, 2020Page 16 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow -ND -73005/29/2007 ----110 49 - 5 190 - --3.8 23 400300 120-T0601300676-MW-5C -7300 -ND ND1211/5/2007 ----- - - -210 - --5 17 ND610 --T0601300676-MW-5C 5.912 -5.2 NDND12/3/2007 ----- - - -260 - --5.2 15 15002200 --T0601300676-MW-5C 6.8ND -5.7 ND111/15/2008 ----- - - -200 - --5.8 11 430490 --T0601300676-MW-5C 8.411 ---7.26/14/2011 ----- - - --- --------T0601300676-MW-5C -7.2 ---910/31/2011 ----- - - --- --------T0601300676-MW-5C -9 ---106/12/2012 ----- - - --- --------T0601300676-MW-5C -10 ---7.65/30/2013 ----- - - --- --------T0601300676-MW-5C -7.6 ---6.411/6/2013 ----- - - --- --------T0601300676-MW-5C -6.4 ---65/7/2014 ----- - - --- --------T0601300676-MW-5C -6 ---2.811/21/2014 ----- - - --- --------T0601300676-MW-5C -2.8 ---6.75/6/2015 ----- - - --- --------T0601300676-MW-5C -6.7 ---6.411/17/2015 ----- - - --- --------T0601300676-MW-5C -6.4 ---6.35/24/2016 ----- - - --- --------T0601300676-MW-5C -6.3 -ND -120005/29/2007 ---<20055 26 - 17 41 - --5.5 12 ND220 ND-T0601300676-MW-6 -12000 ----5/2/2001 ----- - - --- --------T0601300744-W-1 -- ----8/2/2001 ----- - - --- --------T0601300744-W-1 -- ----11/14/2001 ----- - - --- --------T0601300744-W-1 -- ----2/19/2002 ----- - - --- --------T0601300744-W-1 -- ----5/22/2002 ----- - - --- --------T0601300744-W-1 -- ----5/2/2001 ----- - - --- --------T0601300744-W-2 -- ----11/14/2001 ----- - - --- --------T0601300744-W-2 -- ----2/19/2002 ----- - - --- --------T0601300744-W-2 -- ----5/2/2001 ----- - - --- --------T0601300744-W-3 -- ----8/2/2001 ----- - - --- --------T0601300744-W-3 -- ----11/14/2001 ----- - - --- --------T0601300744-W-3 -- ----2/19/2002 ----- - - --- --------T0601300744-W-3 -- ----5/2/2001 ----- - - --- --------T0601300744-W-4 -- ----8/2/2001 ----- - - --- --------T0601300744-W-4 -- ----11/14/2001 ----- - - --- --------T0601300744-W-4 -- ----2/19/2002 ----- - - --- --------T0601300744-W-4 -- ----8/2/2001 ----- - - --- --------T0601300744-W-5B -- ----11/14/2001 ----- - - --- --------T0601300744-W-5B -- ----2/19/2002 ----- - - --- --------T0601300744-W-5B -- ----5/22/2002 ----- - - --- --------T0601300744-W-5B -- ----5/2/2001 ----- - - --- --------T0601300744-W-6 -- ----8/2/2001 ----- - - --- --------T0601300744-W-6 -- ----11/14/2001 ----- - - --- --------T0601300744-W-6 -- ----2/19/2002 ----- - - --- --------T0601300744-W-6 -- Thursday, September 3, 2020Page 17 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----5/22/2002 ----- - - --- --------T0601300744-W-6 -- ----5/2/2001 ----- - - --- --------T0601300744-W-7B -- ----8/2/2001 ----- - - --- --------T0601300744-W-7B -- ----11/14/2001 ----- - - --- --------T0601300744-W-7B -- ----2/19/2002 ----- - - --- --------T0601300744-W-7B -- ----5/22/2002 ----- - - --- --------T0601300744-W-7B -- ----5/2/2001 ----- - - --- --------T0601300744-W-8 -- ----8/2/2001 ----- - - --- --------T0601300744-W-8 -- ----11/14/2001 ----- - - --- --------T0601300744-W-8 -- ----2/19/2002 ----- - - --- --------T0601300744-W-8 -- ----5/22/2002 ----- - - --- --------T0601300744-W-8 -- -50 NDND6/18/2012 ----- - - --- ---<0.5 -150 --T0601300747-MW-1 NDND -23 48ND7/2/2012 ----- - - --- -----180 --T0601300747-MW-1 NDND -120 31ND6/18/2012 ----- - - --- ---18 -400 --T0601300747-MW-2 NDND -110 55ND7/2/2012 ----- - - --- ---<0.5 -300 --T0601300747-MW-2 NDND -46 ND1.56/18/2012 ----- - - --- ---1.7 -160 --T0601300747-MW-3 1.21.5 -74 42ND7/2/2012 ----- - - --- ---<0.5 -200 --T0601300747-MW-3 0.92ND -110 13ND6/18/2012 ----- - - --- ---3.9 -880 --T0601300747-MW-4 0.91ND -90 45ND7/2/2012 ----- - - --- ---<0.5 -630 --T0601300747-MW-4 0.63ND -19 NDND6/18/2012 ----- - - --- ---<0.5 -170 --T0601300747-MW-5 NDND -30 36ND7/2/2012 ----- - - --- ---<0.5 -250 --T0601300747-MW-5 NDND -29 6.6ND6/18/2012 ----- - - --- -----270 --T0601300747-MW-9 NDND -31 40ND7/2/2012 ----- - - --- -----430 --T0601300747-MW-9 NDND ---ND12/12/2008 ----- - - --- ---<0.5 ----T0601300764-MW-16 -ND ---ND12/22/2008 ----- - - --- ---1 ----T0601300764-MW-16 -ND ---1.312/29/2008 ----- - - --- --------T0601300764-MW-16 -1.3 ---4.31/5/2009 ----- - - --- ---12 ----T0601300764-MW-16 -4.3 ---ND3/12/2009 ----- - - --- --------T0601300764-MW-16 -ND ---ND7/30/2009 ----- - - --- ---110 ----T0601300764-MW-16 -ND ---ND12/12/2008 ----- - - --- --------T0601300764-MW-17 -ND ---ND12/22/2008 ----- - - --- --------T0601300764-MW-17 -ND ---ND12/29/2008 ----- - - --- --------T0601300764-MW-17 -ND ---ND1/5/2009 ----- - - --- ---98 ----T0601300764-MW-17 -ND ---ND3/12/2009 ----- - - --- ---1.6 ----T0601300764-MW-17 -ND ---ND7/30/2009 ----- - - --- ---36 ----T0601300764-MW-17 -ND ---ND12/12/2008 ----- - - --- ---<0.5 ----T0601300764-MW-2 -ND ---ND12/22/2008 ----- - - --- ---<0.5 ----T0601300764-MW-2 -ND Thursday, September 3, 2020Page 18 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ---ND12/29/2008 ----- - - --- --------T0601300764-MW-2 -ND ---ND1/5/2009 ----- - - --- ---<0.5 ----T0601300764-MW-2 -ND ---ND3/12/2009 ----- - - --- --------T0601300764-MW-2 -ND ---ND7/30/2009 ----- - - --- ---<0.5 ----T0601300764-MW-2 -ND ---ND12/12/2008 ----- - - --- --------T0601300764-MW-3 -ND ---ND12/22/2008 ----- - - --- ---<0.5 ----T0601300764-MW-3 -ND ---ND12/29/2008 ----- - - --- ---<0.5 ----T0601300764-MW-3 -ND ---ND1/5/2009 ----- - - --- ---<0.5 ----T0601300764-MW-3 -ND ---ND3/12/2009 ----- - - --- ---<0.5 ----T0601300764-MW-3 -ND ---ND7/30/2009 ----- - - --- ---<0.5 ----T0601300764-MW-3 -ND ----6/28/2010 ----- - - --- --26 -----T0601300766-IW10 -- ----11/28/2012 -1400 --- - - --- --------T0601300766-IW10 -- ----6/28/2010 ----- - - --- --23 -----T0601300766-IW9 -- ----11/28/2012 -1500 --- - - --- --------T0601300766-IW9 -- ----6/29/2010 ----- - - --- --48 -----T0601300766-MW1 -- ----11/28/2012 -1200 --- - - --- --------T0601300766-MW1 -- ----6/29/2010 ----- - - --- --14 -----T0601300766-MW2 -- ----11/28/2012 -1200 --- - - --- --------T0601300766-MW2 -- ----6/30/2010 -1940 --- - - -130 - --0.56 -7300---T0601300766-MW3 -- ----10/18/2010 ----- - - --- --26 -----T0601300766-MW3 -- ----1/17/2011 ----- - - --- --22 -----T0601300766-MW3 -- ----11/29/2012 -1400 --- - - --- --------T0601300766-MW3 -- ----1/29/2007 ----- - - -24 - --0.194274 -----T0601300766-MW4 -- ----2/25/2009 -1230 --- - -1.8 19 - --ND -13000---T0601300766-MW4 -- ----6/30/2010 -1340 --- - - -6.6 - --ND -24000---T0601300766-MW4 -- ----10/18/2010 ----- - - --- --ND -----T0601300766-MW4 -- ----1/17/2011 ----- - - --- --ND -----T0601300766-MW4 -- ----11/29/2012 -1400 --- - - --- --------T0601300766-MW4 -- ----8/4/2008 -1650 --- - -15 180 - --4.4 -770---T0601300766-MW5 -- ----9/11/2008 ----- - - --- --3 -----T0601300766-MW5 -- ----9/25/2008 ----- - - --- --4.7 -----T0601300766-MW5 -- ----10/9/2008 ----- - - --- --5.7 -----T0601300766-MW5 -- ----10/23/2008 ----- - - --- --4.2 -----T0601300766-MW5 -- ----12/18/2008 ----- - - --- --2.5 -----T0601300766-MW5 -- ----2/25/2009 -1570 --- - -1.6 200 - --0.37 -890---T0601300766-MW5 -- ----6/30/2010 -1340 --- - - -190 - --0.38 -5100---T0601300766-MW5 -- ----10/18/2010 ----- - - --- --43 -----T0601300766-MW5 -- ----1/17/2011 ----- - - --- --19 -----T0601300766-MW5 -- ----11/29/2012 -1700 --- - - --- --------T0601300766-MW5 -- Thursday, September 3, 2020Page 19 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----11/29/2012 -1500 --- - - --- --------T0601300766-MW6A -- ----6/29/2010 ----- - - --- --62 -----T0601300766-MW6B -- ----11/29/2012 -700 --- - - --- --------T0601300766-MW6B -- ----11/27/2012 -2800 --- - - --- --------T0601300766-MW7A -- ----1/29/2007 ----- - - -260 - --9.9396 -----T0601300766-MW7B -- ----6/29/2010 ----- - - --- --14 -----T0601300766-MW7B -- ----11/27/2012 -1500 --- - - --- --------T0601300766-MW7B -- ----8/4/2008 -1440 --- - -45 230 - --18 -ND---T0601300766-MW8A -- ----12/18/2008 ----- - - --- --14 -----T0601300766-MW8A -- ----2/25/2009 -1400 --- - -2.1 220 - --16 -1200---T0601300766-MW8A -- ----6/29/2010 ----- - - --- --13 -----T0601300766-MW8A -- ----11/27/2012 -1300 --- - - --- --------T0601300766-MW8A -- ----8/4/2008 -1160 --- - -1.3 210 - --20 -170---T0601300766-MW8B -- ----9/10/2008 ----- - - --- --20 -----T0601300766-MW8B -- ----9/25/2008 ----- - - --- --20 -----T0601300766-MW8B -- ----10/9/2008 ----- - - --- --21 -----T0601300766-MW8B -- ----10/23/2008 ----- - - --- --20 -----T0601300766-MW8B -- ----12/18/2008 ----- - - --- --18 -----T0601300766-MW8B -- ----2/25/2009 -1150 --- - -1.2 200 - --19 -ND---T0601300766-MW8B -- ----6/29/2010 ----- - - --- --3.7 -----T0601300766-MW8B -- ----11/27/2012 -1100 --- - - --- --------T0601300766-MW8B -- ----8/4/2008 -1240 --- - -2.3 260 - --15 -1700---T0601300766-MW8C -- ----9/10/2008 ----- - - --- --15 -----T0601300766-MW8C -- ----9/25/2008 ----- - - --- --15 -----T0601300766-MW8C -- ----10/9/2008 ----- - - --- --16 -----T0601300766-MW8C -- ----10/23/2008 ----- - - --- --15 -----T0601300766-MW8C -- ----12/18/2008 ----- - - --- --13 -----T0601300766-MW8C -- ----2/25/2009 -1160 --- - -2.3 250 - --13 -ND---T0601300766-MW8C -- ----6/29/2010 ----- - - --- --7 -----T0601300766-MW8C -- ----10/18/2010 ----- - - --- --10 -----T0601300766-MW8C -- ----1/17/2011 ----- - - --- --11 -----T0601300766-MW8C -- ----11/27/2012 -1200 --- - - --- --------T0601300766-MW8C -- --ND-9/3/2002 ----- - - --- ---<0.01 7800---T0601300772-MW-1 -- --44-10/14/2002 ----- - - --- ----7100---T0601300772-MW-1 -- --ND-11/25/2002 ----- - - --- ---<0.01 4200---T0601300772-MW-1 -- --ND-12/23/2002 ----- - - --- ----7400---T0601300772-MW-1 -- --ND-1/20/2003 ----- - - --- ---<0.005 ----T0601300772-MW-1 -- --52-3/25/2004 ----- - - --- ---<20 13000---T0601300772-MW-1 -- --ND-5/5/2004 ----- - - --- ---<20 ----T0601300772-MW-1 -- Thursday, September 3, 2020Page 20 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow --29-6/3/2004 ----- - - --- ---<20 350---T0601300772-MW-1 -- --ND-8/20/2004 ----- - - --- ---<20 ND---T0601300772-MW-1 -- --ND-9/3/2004 ----- - - --- ---<20 1500---T0601300772-MW-1 -- ----4/1/2011 ----- - - -57.9 - --0.160389 -----T0601300772-MW-1 -- ----7/24/2012 -1030 --104 - - -3.6 - --ND ---1180-T0601300772-MW-1 -- ----4/1/2011 ----- - - -202 - --4.0662 -----T0601300772-MW-12 -- ----4/1/2011 ----- - - -259 - --0.40662 -----T0601300772-MW-13 -- ----7/24/2012 -1220 --120 - - -198 - --ND ---2030-T0601300772-MW-13 -- ----4/1/2011 ----- - - -175 - --0.6777 -----T0601300772-MW-14 -- ----4/1/2011 ----- - - -86 - --1.08432 -----T0601300772-MW-15 -- ----7/28/2011 ----- - - -99.3 - --1.10691 -----T0601300772-MW-15 -- ----7/24/2012 -942 --80.3 - - -107 - --1.15209 ---230-T0601300772-MW-15 -- ----4/1/2011 ----- - - -117 - --1.15209 -----T0601300772-MW-17 -- ----7/28/2011 ----- - - -99.7 - --0.29367 -----T0601300772-MW-17 -- ----7/24/2012 -952 --63.3 - - -146 - --0.72288 ---714-T0601300772-MW-17 -- --ND-9/3/2002 ----- - - --- ---<0.01 14000---T0601300772-MW-2 -- --ND-10/14/2002 ----- - - --- ---<0.01 1100---T0601300772-MW-2 -- --ND-11/25/2002 ----- - - --- ---<0.01 170---T0601300772-MW-2 -- --ND-12/23/2002 ----- - - --- ----210---T0601300772-MW-2 -- --ND-1/20/2003 ----- - - --- ---<0.005 ----T0601300772-MW-2 -- --29-3/25/2004 ----- - - --- ---<20 7000---T0601300772-MW-2 -- --ND-5/5/2004 ----- - - --- ---<20 ----T0601300772-MW-2 -- --32-6/3/2004 ----- - - --- ---<20 ND---T0601300772-MW-2 -- --ND-8/20/2004 ----- - - --- ----ND---T0601300772-MW-2 -- --ND-9/3/2004 ----- - - --- ---<20 ND---T0601300772-MW-2 -- ----4/1/2011 ----- - - -64.3 - --ND -----T0601300772-MW-2 -- ----7/28/2011 ----- - - -34.5 - --ND -----T0601300772-MW-2 -- ----7/24/2012 -1440 --133 - - -51.6 - --ND ---2450-T0601300772-MW-2 -- --ND-9/3/2002 ----- - - --- ----5900---T0601300772-MW-3 -- --ND-10/14/2002 ----- - - --- ---<0.01 4200---T0601300772-MW-3 -- --ND-11/25/2002 ----- - - --- ----5800---T0601300772-MW-3 -- --ND-12/23/2002 ----- - - --- ---<0.005 9600---T0601300772-MW-3 -- --34-1/20/2003 ----- - - --- ---9.1 ----T0601300772-MW-3 -- --ND-3/25/2004 ----- - - --- ---<20 20000---T0601300772-MW-3 -- --ND-5/5/2004 ----- - - --- ---<20 ----T0601300772-MW-3 -- --ND-6/3/2004 ----- - - --- ----990---T0601300772-MW-3 -- --ND-8/20/2004 ----- - - --- ----9500---T0601300772-MW-3 -- --ND-9/3/2004 ----- - - --- ----9800---T0601300772-MW-3 -- ----4/1/2011 ----- - - -3 - --ND -----T0601300772-MW-3 -- Thursday, September 3, 2020Page 21 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----7/28/2011 ----- - - -ND - --0.079065 -----T0601300772-MW-3 -- ----7/24/2012 -1340 --146 - - -ND - --ND ---3050-T0601300772-MW-3 -- --ND-9/3/2002 ----- - - --- ---<0.01 2200---T0601300772-MW-4 -- --ND-10/14/2002 ----- - - --- ---<0.01 2500---T0601300772-MW-4 -- --ND-11/25/2002 ----- - - --- ---<0.01 4500---T0601300772-MW-4 -- --ND-12/23/2002 ----- - - --- ---5 890---T0601300772-MW-4 -- --ND-1/20/2003 ----- - - --- ---7.9 ----T0601300772-MW-4 -- --71-3/25/2004 ----- - - --- ---<20 15000---T0601300772-MW-4 -- --ND-5/5/2004 ----- - - --- ---<20 ----T0601300772-MW-4 -- --ND-6/3/2004 ----- - - --- ---<20 ND---T0601300772-MW-4 -- --ND-8/20/2004 ----- - - --- ----1500---T0601300772-MW-4 -- --ND-9/3/2004 ----- - - --- ---<20 2900---T0601300772-MW-4 -- ----4/1/2011 ----- - - -4.6 - --ND -----T0601300772-MW-4 -- ----7/28/2011 ----- - - -ND - --ND -----T0601300772-MW-4 -- ----7/24/2012 -1140 --91.9 - - -ND - --ND ---1250-T0601300772-MW-4 -- ----4/1/2011 ----- - - -152 - --3.72735 -----T0601300772-MW-5 -- ----4/1/2011 ----- - - -250 - --0.09036 -----T0601300772-MW-6 -- --ND-3/25/2004 ----- - - --- ---<20 3800---T0601300772-MW-7 -- --ND-4/6/2004 ----- - - --- ---<20 1300---T0601300772-MW-7 -- --ND-5/5/2004 ----- - - --- ---<20 ----T0601300772-MW-7 -- --ND-6/3/2004 ----- - - --- ---<20 270---T0601300772-MW-7 -- --ND-6/24/2004 ----- - - --- ---<20 1600---T0601300772-MW-7 -- --ND-7/15/2004 ----- - - --- ---<20 2000---T0601300772-MW-7 -- --ND-8/20/2004 ----- - - --- ---<20 1600---T0601300772-MW-7 -- --ND-9/3/2004 ----- - - --- ---<20 2700---T0601300772-MW-7 -- ----4/1/2011 ----- - - -80.5 - --ND -----T0601300772-MW-7 -- ----7/28/2011 ----- - - -80.9 - --ND -----T0601300772-MW-7 -- ----7/24/2012 -1150 --113 - - -48.7 - --0.065511 ---3580-T0601300772-MW-7 -- --25-3/25/2004 ----- - - --- ----1400---T0601300772-MW-8 -- --ND-4/6/2004 ----- - - --- ----450---T0601300772-MW-8 -- --ND-5/5/2004 ----- - - --- --------T0601300772-MW-8 -- --ND-6/3/2004 ----- - - --- ---<20 ND---T0601300772-MW-8 -- --ND-6/24/2004 ----- - - --- ----800---T0601300772-MW-8 -- --ND-7/15/2004 ----- - - --- ----940---T0601300772-MW-8 -- --ND-8/20/2004 ----- - - --- ---<20 850---T0601300772-MW-8 -- --ND-9/3/2004 ----- - - --- ---<20 880---T0601300772-MW-8 -- ----4/1/2011 ----- - - -10.9 - --ND -----T0601300772-MW-8 -- ----7/28/2011 ----- - - -ND - --ND -----T0601300772-MW-8 -- ----7/24/2012 -892 --83.9 - - -ND - --ND ---2390-T0601300772-MW-8 -- ----11/28/2006 ----- - - --- --------T0601300776-CES-17 -- Thursday, September 3, 2020Page 22 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----11/28/2006 ----- - - --- --------T0601300776-CES-18 -- ----7/26/2005 ----- - - --- --------T0601300776-KMW-10 -- ----9/30/2008 ----- - - --- --------T0601300776-KMW-10 -- ----9/30/2008 ----- - - --- --------T0601300776-KMW-11 -- ----9/30/2008 ----- - - --- --------T0601300776-KMW-8 -- ----12/16/2008 ----- - - -550 - --ND -10400-3170-T0601300776-KMW-8 -- ----7/26/2005 ----- - - --- --------T0601300776-KMW-9 -- ----9/30/2008 ----- - - --- --------T0601300776-MW-12 -- ----7/26/2005 ----- - - --- --------T0601300776-MW-2 -- ----7/26/2005 ----- - - --- --------T0601300776-MW-3 -- ----12/16/2008 ----- - - -ND - --ND -29000-1510-T0601300776-MW-3 -- ----7/26/2005 ----- - - --- --------T0601300776-MW-5 -- ----9/30/2008 ----- - - --- --------T0601300776-MW-5 -- ----9/30/2008 ----- - - --- --------T0601300776-MW-6 -- ----12/16/2008 ----- - - -1240 - --ND -220-255-T0601300776-MW-6 -- ----7/26/2005 ----- - - --- --------T0601300776-MW-7A -- ----9/30/2008 ----- - - --- --------T0601300776-SG-10 -- ----10/23/2008 ----- - - -24 - --ND -----T0601300782-MW-1 -- ----10/23/2008 ----- - - -120 - --4.8 -----T0601300782-MW-11 -- ----10/23/2008 ----- - - -170 - --27.108 -----T0601300782-MW-12 -- ----10/23/2008 ----- - - -46 - --ND -----T0601300782-MW-2 -- ----10/23/2008 ----- - - -49 - --0.88101 -----T0601300782-MW-3 -- ----10/23/2008 ----- - - -75 - --6.5511 -----T0601300782-MW-6 -- ----10/23/2008 ----- - - -24 - --ND -----T0601300782-MW-7 -- ----3/31/2005 6880 3630 6.86 -260 280 1000 28 0.5 1600 ----28000-1300-T0601300788-MW-1 -- ----3/31/2005 5010 3130 6.61 -150 87 900 8.7 23 1800 ----52000-1100-T0601300788-MW-2 -- ----3/31/2005 8520 4790 6.96 -370 280 1000 12 1700 1400 ----34000-3600-T0601300788-MW-3 -- ----4/1/2005 21300 12500 7.46 -640 560 3500 20 4800 3400 ----29000-2900-T0601300788-MW-4 -- ----4/1/2005 11500 6430 7.18 -450 300 1700 27 1.6 3300 ----70000-3600-T0601300788-MW-5 -- ---ND9/14/2006 ----- - - --- --------T0601300800-BW-1 -ND ---ND12/11/2006 ----- - - --- --------T0601300800-BW-1 -ND Thursday, September 3, 2020Page 23 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ---ND3/5/2007 ----- - - --- --------T0601300800-BW-1 -ND ---ND6/11/2007 ----- - - --- --------T0601300800-BW-1 -ND ---ND9/12/2007 ----- - - --- --------T0601300800-BW-1 -ND ---ND12/13/2007 ----- - - --- --------T0601300800-BW-1 -ND ---ND3/10/2008 ----- - - --- --------T0601300800-BW-1 -ND ---ND6/11/2008 ----- - - --- --------T0601300800-BW-1 -ND ---ND9/11/2008 ----- - - --- --------T0601300800-BW-1 -ND ---ND12/9/2008 ----- - - --- --------T0601300800-BW-1 -ND ---ND9/14/2006 ----- - - --- --------T0601300800-MW-2 -ND ---ND12/11/2006 ----- - - --- --------T0601300800-MW-2 -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-2 -ND ---ND6/11/2007 ----- - - --- --------T0601300800-MW-2 -ND ---ND9/12/2007 ----- - - --- --------T0601300800-MW-2 -ND ---ND12/13/2007 ----- - - --- --------T0601300800-MW-2 -ND ---ND3/10/2008 ----- - - --- --------T0601300800-MW-2 -ND ---ND6/11/2008 ----- - - --- --------T0601300800-MW-2 -ND ---ND9/11/2008 ----- - - --- --------T0601300800-MW-2 -ND ---ND12/9/2008 ----- - - --- --------T0601300800-MW-2 -ND ---ND9/14/2006 ----- - - --- --------T0601300800-MW-3 -ND ---ND12/11/2006 ----- - - --- --------T0601300800-MW-3 -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-3 -ND ---ND6/11/2007 ----- - - --- --------T0601300800-MW-3 -ND ---ND9/12/2007 ----- - - --- --------T0601300800-MW-3 -ND ---ND12/13/2007 ----- - - --- --------T0601300800-MW-3 -ND ---ND3/10/2008 ----- - - --- --------T0601300800-MW-3 -ND ---ND6/11/2008 ----- - - --- --------T0601300800-MW-3 -ND ---ND9/11/2008 ----- - - --- --------T0601300800-MW-3 -ND ---1212/9/2008 ----- - - --- --------T0601300800-MW-3 -12 ---ND9/14/2006 ----- - - --- --------T0601300800-MW-4A -ND ---ND12/11/2006 ----- - - --- --------T0601300800-MW-4A -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-4A -ND ---126/11/2007 ----- - - --- --------T0601300800-MW-4A -12 ---ND9/12/2007 ----- - - --- --------T0601300800-MW-4A -ND ---ND12/13/2007 ----- - - --- --------T0601300800-MW-4A -ND ---ND3/10/2008 ----- - - --- --------T0601300800-MW-4A -ND ---ND6/11/2008 ----- - - --- --------T0601300800-MW-4A -ND ---ND9/11/2008 ----- - - --- --------T0601300800-MW-4A -ND ---ND12/9/2008 ----- - - --- --------T0601300800-MW-4A -ND ---ND9/14/2006 ----- - - --- --------T0601300800-MW-4B -ND ---ND12/11/2006 ----- - - --- --------T0601300800-MW-4B -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-4B -ND Thursday, September 3, 2020Page 24 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ---136/11/2007 ----- - - --- --------T0601300800-MW-4B -13 ---ND9/12/2007 ----- - - --- --------T0601300800-MW-4B -ND ---ND12/13/2007 ----- - - --- --------T0601300800-MW-4B -ND ---ND3/10/2008 ----- - - --- --------T0601300800-MW-4B -ND ---ND6/11/2008 ----- - - --- --------T0601300800-MW-4B -ND ---ND9/11/2008 ----- - - --- --------T0601300800-MW-4B -ND ---ND12/9/2008 ----- - - --- --------T0601300800-MW-4B -ND ---ND9/14/2006 ----- - - --- --------T0601300800-MW-5B -ND ---ND12/11/2006 ----- - - --- --------T0601300800-MW-5B -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-5B -ND ---ND6/11/2007 ----- - - --- --------T0601300800-MW-5B -ND ---ND9/12/2007 ----- - - --- --------T0601300800-MW-5B -ND ---ND12/13/2007 ----- - - --- --------T0601300800-MW-5B -ND ---ND3/10/2008 ----- - - --- --------T0601300800-MW-5B -ND ---ND6/11/2008 ----- - - --- --------T0601300800-MW-5B -ND ---ND9/11/2008 ----- - - --- --------T0601300800-MW-5B -ND ---ND12/9/2008 ----- - - --- --------T0601300800-MW-5B -ND ---ND9/14/2006 ----- - - --- --------T0601300800-MW-6A -ND ---ND12/11/2006 ----- - - --- --------T0601300800-MW-6A -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-6A -ND ---ND6/11/2007 ----- - - --- --------T0601300800-MW-6A -ND ---ND9/12/2007 ----- - - --- --------T0601300800-MW-6A -ND ---ND12/13/2007 ----- - - --- --------T0601300800-MW-6A -ND ---ND3/10/2008 ----- - - --- --------T0601300800-MW-6A -ND ---ND6/11/2008 ----- - - --- --------T0601300800-MW-6A -ND ---ND9/11/2008 ----- - - --- --------T0601300800-MW-6A -ND ---ND12/9/2008 ----- - - --- --------T0601300800-MW-6A -ND ---ND9/14/2006 ----- - - --- --------T0601300800-MW-6B -ND ---ND12/11/2006 ----- - - --- --------T0601300800-MW-6B -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-6B -ND ---ND6/11/2007 ----- - - --- --------T0601300800-MW-6B -ND ---ND9/12/2007 ----- - - --- --------T0601300800-MW-6B -ND ---ND12/13/2007 ----- - - --- --------T0601300800-MW-6B -ND ---ND3/10/2008 ----- - - --- --------T0601300800-MW-6B -ND ---ND6/11/2008 ----- - - --- --------T0601300800-MW-6B -ND ---ND9/11/2008 ----- - - --- --------T0601300800-MW-6B -ND ---ND12/9/2008 ----- - - --- --------T0601300800-MW-6B -ND ---189/14/2006 ----- - - --- --------T0601300800-MW-7B -18 ---ND12/11/2006 ----- - - --- --------T0601300800-MW-7B -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-7B -ND ---116/11/2007 ----- - - --- --------T0601300800-MW-7B -11 Thursday, September 3, 2020Page 25 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ---ND9/12/2007 ----- - - --- --------T0601300800-MW-7B -ND ---ND12/13/2007 ----- - - --- --------T0601300800-MW-7B -ND ---ND3/10/2008 ----- - - --- --------T0601300800-MW-7B -ND ---ND6/11/2008 ----- - - --- --------T0601300800-MW-7B -ND ---ND9/11/2008 ----- - - --- --------T0601300800-MW-7B -ND ---ND12/9/2008 ----- - - --- --------T0601300800-MW-7B -ND ---ND9/14/2006 ----- - - --- --------T0601300800-MW-7BL -ND ---ND12/11/2006 ----- - - --- --------T0601300800-MW-7BL -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-7BL -ND ---126/11/2007 ----- - - --- --------T0601300800-MW-7BL -12 ---ND9/12/2007 ----- - - --- --------T0601300800-MW-7BL -ND ---ND12/13/2007 ----- - - --- --------T0601300800-MW-7BL -ND ---ND3/10/2008 ----- - - --- --------T0601300800-MW-7BL -ND ---116/11/2008 ----- - - --- --------T0601300800-MW-7BL -11 ---ND9/11/2008 ----- - - --- --------T0601300800-MW-7BL -ND ---1012/9/2008 ----- - - --- --------T0601300800-MW-7BL -10 ---129/14/2006 ----- - - --- --------T0601300800-MW-8A -12 ---ND12/11/2006 ----- - - --- --------T0601300800-MW-8A -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-8A -ND ---116/11/2007 ----- - - --- --------T0601300800-MW-8A -11 ---ND9/12/2007 ----- - - --- --------T0601300800-MW-8A -ND ---1012/13/2007 ----- - - --- --------T0601300800-MW-8A -10 ---ND3/10/2008 ----- - - --- --------T0601300800-MW-8A -ND ---ND6/11/2008 ----- - - --- --------T0601300800-MW-8A -ND ---ND9/11/2008 ----- - - --- --------T0601300800-MW-8A -ND ---ND12/9/2008 ----- - - --- --------T0601300800-MW-8A -ND ---ND9/14/2006 ----- - - --- --------T0601300800-MW-8BL -ND ---ND12/11/2006 ----- - - --- --------T0601300800-MW-8BL -ND ---ND3/5/2007 ----- - - --- --------T0601300800-MW-8BL -ND ---ND6/11/2007 ----- - - --- --------T0601300800-MW-8BL -ND ---ND9/12/2007 ----- - - --- --------T0601300800-MW-8BL -ND ---ND12/13/2007 ----- - - --- --------T0601300800-MW-8BL -ND ---ND3/10/2008 ----- - - --- --------T0601300800-MW-8BL -ND ---ND6/11/2008 ----- - - --- --------T0601300800-MW-8BL -ND ---ND9/11/2008 ----- - - --- --------T0601300800-MW-8BL -ND ---ND12/9/2008 ----- - - --- --------T0601300800-MW-8BL -ND -76.5 --1/17/2008 ----- - - --- ---<5 9150---T0601300807-IP-1 -- -10 --2/21/2008 ----- - - --- ---32.2 ----T0601300807-IP-1 -- -10 --3/18/2008 ----- - - --- ---<5 ----T0601300807-IP-1 -- -10 --5/14/2008 ----- - - --- --------T0601300807-IP-1 -- -10 --6/12/2008 ----- - - --- --------T0601300807-IP-1 -- Thursday, September 3, 2020Page 26 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow -39.3 --1/17/2008 ----- - - --- ---<5 3490---T0601300807-IP-2 -- -10 --2/21/2008 ----- - - --- ---<5 ----T0601300807-IP-2 -- -10 --3/17/2008 ----- - - --- ---<5 ----T0601300807-IP-2 -- -10 --5/14/2008 ----- - - --- --------T0601300807-IP-2 -- -10 --6/12/2008 ----- - - --- ---<5 ----T0601300807-IP-2 -- -22.3 --1/17/2008 ----- - - --- ---<5 1760---T0601300807-OW-1 -- -19.9 --2/21/2008 ----- - - --- ---<5 ----T0601300807-OW-1 -- -21.8 --3/18/2008 ----- - - --- ---<5 ----T0601300807-OW-1 -- -46.6 --5/14/2008 ----- - - --- ---<5 ----T0601300807-OW-1 -- -12.3 --6/11/2008 ----- - - --- ---<5 ----T0601300807-OW-1 -- -18.7 --1/17/2008 ----- - - --- ----2430---T0601300807-OW-2 -- -10 --2/21/2008 ----- - - --- ---<5 ----T0601300807-OW-2 -- -21.5 --3/18/2008 ----- - - --- ---<5 ----T0601300807-OW-2 -- -39.3 --5/14/2008 ----- - - --- ---<5 ----T0601300807-OW-2 -- -42.5 --6/11/2008 ----- - - --- ---<5 ----T0601300807-OW-2 -- -32.6 --1/17/2008 ----- - - --- ---<5 6030---T0601300807-S-11 -- -16.8 --2/21/2008 ----- - - --- ---26.1 ----T0601300807-S-11 -- -14.9 --3/17/2008 ----- - - --- ---<5 ----T0601300807-S-11 -- -25 --5/14/2008 ----- - - --- ---<5 ----T0601300807-S-11 -- -13.8 --6/11/2008 ----- - - --- ---<5 ----T0601300807-S-11 -- -10 --1/17/2008 ----- - - --- ---<5 2180---T0601300807-S-15 -- -10 --2/21/2008 ----- - - --- ---<5 ----T0601300807-S-15 -- -10 --3/18/2008 ----- - - --- ---<5 ----T0601300807-S-15 -- -10 --5/14/2008 ----- - - --- ---<5 ----T0601300807-S-15 -- -10 --6/12/2008 ----- - - --- ---<5 ----T0601300807-S-15 -- ----5/11/2004 ----- - - -1.6 - -840 ND -----T0601300810-MW-1 -- ----5/11/2004 ----- - - -55 - -210 1.96533 -----T0601300810-MW-2 -- ----5/11/2004 ----- - - -240 - -310 ND -----T0601300810-MW-3 -- ----5/11/2004 ----- - - -56 - -660 ND -----T0601300810-MW-4 -- ----5/11/2004 ----- - - -5.2 - -610 ND -----T0601300810-MW-5 -- ----5/11/2004 ----- - - -ND - -1400 ND -----T0601300810-MW-6 -- ----5/11/2004 ----- - - -12 - -480 ND -----T0601300810-MW-7 -- ----3/6/2013 ----- - - --- ----100---T0601325015-MPE-1 -- ----3/6/2013 ----- - - --- ----ND---T0601325015-MPE-2 -- ----3/6/2013 ----- - - --- ----ND---T0601325015-MPE-3 -- Thursday, September 3, 2020Page 27 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----3/6/2013 ----- - - --- ----270---T0601325015-MW-2 -- ----3/6/2013 ----- - - --- ----ND---T0601325015-MW-3 -- ----3/6/2013 ----- - - --- ----1000---T0601325015-MW-4R -- ----3/6/2013 ----- - - --- ----ND---T0601325015-MW-5 -- -69 ND-7/12/2007 ---<0.04- - - --- ---<0.01 -ND --T0601343310-EW1 ND- -ND ND-10/5/2010 ----- - - --- -----200 --T0601343310-EW1 ND- -96 ND-7/12/2007 ---<0.04- - - --- ---<0.01 -ND --T0601343310-EW2 ND- -ND ND-10/5/2010 ----- - - --- ---10 -110 --T0601343310-EW2 ND- -170 ND-7/12/2007 ---3600- - - --- ---<0.01 -ND --T0601343310-EW3 ND- -ND ND-10/5/2010 ----- - - --- ---13 -78 --T0601343310-EW3 ND- -ND ND-7/12/2007 ---<0.04- - - --- -----ND --T0601343310-MW4 ND- -ND 68-10/5/2010 ----- - - --- -----130 --T0601343310-MW4 ND- -2.4 ND-12/19/2006 ----- - - --- -----49 --T0601358660-MW1 1.6- -2.5 ND-12/19/2006 ----- - - --- -----83 --T0601358660-MW2 2.6- -3.5 ND-12/19/2006 ----- - - --- ---7.2 -22 --T0601358660-MW3 1.5- -2.4 ND-12/19/2006 ----- - - --- ---1.3 -55 --T0601358660-MW4 ND- ----9/25/2018 -1440 --- - - --- --------T0601359797-RW-2 -- -9.8 --4/20/2006 ----- - - --- --------T0601391420-EX-1 -- -130 --4/20/2006 ----- - - --- --------T0601391420-EX-2 -- ---ND12/1/2009 7780 6220 7.17 -360 200 1200 20 2900 490 --ND <0.5 76063 2100-T10000000655-MW.01 -ND ---ND8/24/2010 ----340 93 360 7.5 1200 120 --ND <0.5 ND47 8000-T10000000655-MW.01 -ND ---ND10/4/2010 ----- - - --- ---0.79 ----T10000000655-MW.01 -ND ---ND11/5/2010 ----- - - --- ---<0.5 ----T10000000655-MW.01 -ND ---ND12/1/2009 15800 12600 7.12 -570 380 2800 31 4500 2300 --ND 1.1 51075 2000-T10000000655-MW.02 -ND ---ND8/24/2010 ----460 230 1200 12 3300 580 --ND 11 150045 11000-T10000000655-MW.02 -ND ---ND10/4/2010 ----- - - --- ---<0.5 ----T10000000655-MW.02 -ND ---ND11/5/2010 ----- - - --- ---3.8 ----T10000000655-MW.02 -ND ---ND12/1/2009 25800 20400 7.09 -630 550 5300 40 8500 4900 --ND <0.5 ND460 5700-T10000000655-MW.03 -ND ---ND8/24/2010 ----440 330 2900 18 5700 1400 --ND 8.6 ND38 9000-T10000000655-MW.03 -ND ---ND10/4/2010 ----- - - --- ---0.6 ----T10000000655-MW.03 -ND ---ND11/5/2010 ----- - - --- ---0.84 ----T10000000655-MW.03 -ND ---ND12/1/2009 7070 5640 7.32 -360 180 1100 16 2600 540 --ND <0.5 470076 1300-T10000000655-MW.04 -ND ---3.28/24/2010 ----250 80 590 7.2 1000 120 --ND 4.1 ND91 2000-T10000000655-MW.04 -3.2 ---2.510/4/2010 ----- - - --- ---2.6 ----T10000000655-MW.04 -2.5 Thursday, September 3, 2020Page 28 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ---6.811/5/2010 ----- - - --- ---6.7 ----T10000000655-MW.04 -6.8 ---ND12/1/2009 4310 2910 7.14 -280 140 800 15 1000 590 --ND <0.5 240110 410-T10000000655-MW.05 -ND ---ND1/4/2010 ----170 63 250 8.1 80 70 --ND <5 1000140 2200-T10000000655-MW.05 -ND ---ND1/5/2010 ----170 57 220 6.6 260 66 --ND <5 650160 2000-T10000000655-MW.05 -ND ---ND1/7/2010 ----220 74 310 7.7 200 65 --ND <0.5 53110 980-T10000000655-MW.05 -ND ---ND1/11/2010 ----180 54 250 6.5 350 87 --ND <5 ND120 830-T10000000655-MW.05 -ND ---198/24/2010 ----130 37 150 5 11 51 --ND 25 78290 3500-T10000000655-MW.05 -19 ---6.110/4/2010 ----- - - --- ---6.7 ----T10000000655-MW.05 -6.1 ---1611/5/2010 ----- - - --- ---17 ----T10000000655-MW.05 -16 ---ND12/1/2009 6790 5120 7.3 -270 140 1100 15 1600 590 --ND <0.5 160093 610-T10000000655-MW.06 -ND ---ND1/4/2010 ----320 130 1000 7.4 990 220 --ND <5 25060 1300-T10000000655-MW.06 -ND ---ND1/5/2010 ----260 110 920 7 3600 830 --ND <5 650120 1200-T10000000655-MW.06 -ND ---ND1/7/2010 ----300 130 950 8.5 790 260 --ND <5 36079 1100-T10000000655-MW.06 -ND ---ND1/11/2010 ----220 84 950 5.7 1800 300 --ND <5 960110 940-T10000000655-MW.06 -ND ---678/24/2010 ----99 36 350 4.4 190 100 --0.29 63 ND180 1200-T10000000655-MW.06 -67 ---0.710/4/2010 ----- - - --- ---1.1 ----T10000000655-MW.06 -0.7 ---8.111/5/2010 ----- - - --- ---9.6 ----T10000000655-MW.06 -8.1 ---ND12/1/2009 1240 744 7.52 -41 22 280 7 130 65 --ND <0.5 80049 270-T10000000655-MW.07 -ND ---ND1/4/2010 ----35 13 150 3.5 8.3 25 --ND <5 76063 470-T10000000655-MW.07 -ND ---ND1/5/2010 ----36 16 160 4.2 37 32 --ND <5 25063 360-T10000000655-MW.07 -ND ---ND1/7/2010 ----42 16 180 4.1 57 310 --ND <5 13063 410-T10000000655-MW.07 -ND ---ND1/11/2010 ----37 14 180 4 39 31 --0.164907 <5 13053 280-T10000000655-MW.07 -ND ---2.98/24/2010 ----24 8 110 3 8.2 33 --0.13 3.1 ND69 360-T10000000655-MW.07 -2.9 ---0.7410/4/2010 ----- - - --- ---0.62 ----T10000000655-MW.07 -0.74 ---4.611/5/2010 ----- - - --- ---5 ----T10000000655-MW.07 -4.6 ---ND12/1/2009 4060 2900 7.2 -260 96 600 12 890 470 --ND <0.5 420120 1400-T10000000655-MW.08 -ND ---ND1/4/2010 ----180 44 150 5.4 170 97 --ND <5 3300180 3800-T10000000655-MW.08 -ND ---ND1/5/2010 ----190 45 170 4.7 130 100 --ND <0.5 1600200 3500-T10000000655-MW.08 -ND ---ND1/7/2010 ----180 39 150 4.7 140 100 --ND <5 1900170 3000-T10000000655-MW.08 -ND ---ND1/11/2010 ----190 40 150 4.6 140 100 --ND <0.5 1400170 3200-T10000000655-MW.08 -ND ---6.68/24/2010 ----120 26 120 4.6 16 71 --0.12 6.2 ND310 2800-T10000000655-MW.08 -6.6 ---0.9510/4/2010 ----- - - --- ---1.1 ----T10000000655-MW.08 -0.95 ---1811/5/2010 ----- - - --- ---18 ----T10000000655-MW.08 -18 ---ND12/1/2009 19900 13000 7.51 -580 430 2500 23 5700 3000 --ND 40 2300070 460-T10000000655-MW.09 -ND ---ND1/4/2010 ----340 150 1000 11 2100 460 --10 <0.5 ND45 620-T10000000655-MW.09 -ND ---621/5/2010 ----150 64 260 11 490 86 --3.1 69 140088 2900-T10000000655-MW.09 -62 ---5.81/7/2010 ----130 46 170 10 290 46 --0.38403 9.5 43081 1600-T10000000655-MW.09 -5.8 ---ND1/11/2010 ----140 47 140 7.5 280 28 --ND <0.5 13081 1300-T10000000655-MW.09 -ND ---458/24/2010 ----95 27 110 5.8 58 26 --ND 32 ND360 920-T10000000655-MW.09 -45 ---0.6610/4/2010 ----- - - --- ---3.5 ----T10000000655-MW.09 -0.66 Thursday, September 3, 2020Page 29 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ---1711/5/2010 ----- - - --- ---16 ----T10000000655-MW.09 -17 ---ND12/1/2009 11400 9300 7.36 -500 380 2200 18 4400 1000 --ND <0.5 ND59 2200-T10000000655-MW.10 -ND ---ND8/24/2010 ----480 290 1700 12 3600 790 --ND 8.9 ND42 3800-T10000000655-MW.10 -ND ---ND10/4/2010 ----- - - --- ---6 ----T10000000655-MW.10 -ND ---ND11/5/2010 ----- - - --- ---0.59 ----T10000000655-MW.10 -ND ---ND8/24/2010 ----450 130 400 9.7 1700 140 --ND 33 26033 7400-T10000000655-MW.11 -ND ---ND10/4/2010 ----- - - --- ---30 ----T10000000655-MW.11 -ND ---ND11/5/2010 ----- - - --- ---0.54 ----T10000000655-MW.11 -ND ---ND8/24/2010 ----390 140 780 9 1700 150 --ND <0.5 11059 6700-T10000000655-MW.12 -ND ---ND10/4/2010 ----- - - --- ---0.88 ----T10000000655-MW.12 -ND ---ND11/5/2010 ----- - - --- ---0.87 ----T10000000655-MW.12 -ND ---ND8/24/2010 ----410 140 520 10 1300 150 --ND <0.5 ND94 4400-T10000000655-MW.13 -ND ---ND10/4/2010 ----- - - --- ---<0.5 ----T10000000655-MW.13 -ND ---111/5/2010 ----- - - --- ---1.5 ----T10000000655-MW.13 -1 ---ND8/24/2010 ----190 34 310 4.6 470 180 --ND <0.5 100043 2400-T10000000655-MW.14 -ND ---ND10/4/2010 ----- - - --- ---<0.5 ----T10000000655-MW.14 -ND ---ND11/5/2010 ----- - - --- ---<0.5 ----T10000000655-MW.14 -ND 0.64 ---11/9/2010 -1200 --140 62 210 1.4 480 170 --ND ---1300-T10000002015-MW-1 -- 0.54 ---3/2/2011 -1200 --130 60 200 1.5 430 150 --ND -700---T10000002015-MW-1 -- 0.61 ---6/1/2011 -1200 --140 65 220 1.6 420 150 --ND -710---T10000002015-MW-1 -- 0.47 ---8/31/2011 -1200 --120 59 200 1.4 460 140 --ND -600---T10000002015-MW-1 -- 0.53 ---11/9/2010 -1400 --160 64 220 1.6 540 160 --ND ---2800-T10000002015-MW-2 -- 0.47 ---3/2/2011 -1400 --160 62 200 2 480 150 --ND -820---T10000002015-MW-2 -- 0.51 ---6/1/2011 -1300 --150 62 210 1.6 460 140 --ND -850---T10000002015-MW-2 -- 0.4 ---8/31/2011 -1300 --180 67 190 3.6 510 140 --ND -660---T10000002015-MW-2 -- 0.55 ---11/8/2010 -1300 --150 57 210 2.7 510 160 --3 ---530-T10000002015-MW-3 -- 0.44 ---3/2/2011 -950 --140 44 160 3.5 350 110 --2 -580---T10000002015-MW-3 -- 0.48 ---6/1/2011 -1200 --150 53 200 3 450 140 --1.3 -720---T10000002015-MW-3 -- 0.4 ---8/31/2011 -1300 --140 51 180 2.5 480 130 --1.5 -620---T10000002015-MW-3 -- 0.36 ---11/8/2010 -1700 --210 71 210 1.6 790 150 --6.3 ---1100-T10000002015-MW-4 -- 0.32 ---3/2/2011 -1600 --230 74 210 3.2 650 140 --5.9 -920---T10000002015-MW-4 -- 0.35 ---6/1/2011 -1600 --220 75 210 1.8 680 140 --5.7 -1100---T10000002015-MW-4 -- 0.31 ---8/31/2011 -1600 --210 72 190 2.3 730 140 --5.2 -880---T10000002015-MW-4 -- 0.77 ---11/9/2010 -1100 --88 65 210 2.1 230 170 --ND ---390-T10000002015-MW-5 -- 0.66 ---3/2/2011 -1100 --97 70 220 2 220 150 --ND -440---T10000002015-MW-5 -- 0.65 ---6/1/2011 -1100 --99 72 230 2.2 230 160 --ND -460---T10000002015-MW-5 -- 0.56 ---8/31/2011 -1100 --97 65 200 2.2 260 150 --ND -380---T10000002015-MW-5 -- Thursday, September 3, 2020Page 30 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----6/16/2014 -530 --- - - --- --------T10000003258-MW-3 -- ----6/16/2014 -700 --- - - --- --------T10000003258-MW-5 -- ----6/16/2014 -730 --- - - --- --------T10000003258-MW-6 -- ----8/9/1973 4000 1720 7.8 -52 22 560 5.5 160 700 330271 2.12 ----6500USGS-375106121372201 -- ----6/24/1975 3750 -7.6 -- -600 --780 310254 ------USGS-375106121372201 -- ----7/20/1977 4050 -7.5 -- -780 --1210 270221 ------USGS-375106121372201 -- 0.3 ---6/5/1979 1110 640 7.6 -64 29 110 1.9 84 140 -270 3.39 ----1900USGS-375202121383101 -- 0.6 ---5/1/1979 1790 1199 7.7 -94 70 180 1 190 330 -310 ND ----3100USGS-375347121372201 -- 0.4 3 --5/2/1979 2030 1280 7.7 100100 68 260 2.1 180 260 -480 12 -30-103800USGS-375410121412401 -- 0.2 2 --5/1/1979 1380 883 7.4 10098 54 110 1.8 130 170 -310 6.8 -10-1401800USGS-375427121422601 -- 0.3 ---5/1/1979 4270 3523 7.2 -260 130 700 12 1600 370 -530 0.81 ----1800USGS-375449121435301 -- ----8/9/1973 1180 610 7.7 -68 34 110 0.3 97 140 280230 3.61 ----1600USGS-375600121402601 -- -1 1200-6/24/1975 1300 -7.5 -- -120 --160 320262 --90-10-USGS-375600121402601 -- ----7/20/1977 1260 -7.3 -- -110 --220 290238 ------USGS-375600121402601 -- ----7/19/1974 1950 1090 7.7 -130 55 150 3.5 310 210 300246 10.8 ----1100USGS-375601121415201 -- ----6/15/1976 1520 -7.4 -- -140 --190 260213 ------USGS-375601121415201 -- 0.2 3 --5/2/1979 1600 994 7.5 10092 52 180 1.5 210 260 -250 4.7 -10-102000USGS-375701121392901 -- 1.2 2 --5/1/1979 2200 1510 7.6 100130 52 320 2.7 540 280 -220 5.4 -20-102400USGS-375738121441501 -- 0.5 ---5/1/1979 1260 1020 7.5 -120 54 150 6.2 270 190 -250 8.4 ----700USGS-375753121422801 -- 0.2 ---6/5/1979 1730 934 7.6 -150 60 95 4.3 69 320 -310 2.7 ----200USGS-375831121424001 -- 0.1 3 --6/5/1979 1860 1258 7.4 100140 82 150 3.2 310 170 -360 21 -10-3001700USGS-375916121403401 -- ----6/22/1972 863 ---- - - --76 --------USGS-380012121461101 -- ----7/19/1972 870 ---- - - --77 --------USGS-380012121461101 -- ----8/23/1972 862 ---- - - --74 --------USGS-380012121461101 -- ----9/20/1972 869 ---- - - --75 --------USGS-380012121461101 -- ----11/15/1972 847 ---- - - --73 --------USGS-380012121461101 -- ----12/19/1972 886 ---- - - --73 --------USGS-380012121461101 -- ----1/25/1973 854 ---- - - --72 --------USGS-380012121461101 -- ----2/20/1973 882 ---- - - --76 --------USGS-380012121461101 -- ----3/21/1973 882 ---- - - --76 --------USGS-380012121461101 -- ----5/23/1973 872 ---- - - --77 --------USGS-380012121461101 -- ----10/4/1973 876 ---- - - --78 --------USGS-380012121461101 -- ----3/11/1974 890 ---- - - --82 --------USGS-380012121461101 -- ----9/24/1974 892 ---- - - --89 --------USGS-380012121461101 -- ----4/7/1975 900 ---- - - --93 --------USGS-380012121461101 -- Thursday, September 3, 2020Page 31 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----9/16/1975 891 ---- - - --90 --------USGS-380012121461101 -- ----4/12/1976 907 ---- - - --89 --------USGS-380012121461101 -- ----9/15/1976 889 ---- - - --91 --------USGS-380012121461101 -- ----4/26/1977 962 ---- - - --93 --------USGS-380012121461101 -- ----9/13/1977 991 ---- - - --93 --------USGS-380012121461101 -- ----4/17/1978 949 ---- - - --95 --------USGS-380012121461101 -- ----9/25/1978 892 ---- - - --92 --------USGS-380012121461101 -- ----4/17/1979 890 ---- - - --100 --------USGS-380012121461101 -- ----9/24/1979 872 ---- - - --110 --------USGS-380012121461101 -- ----4/10/1980 916 ---- - - --98 --------USGS-380012121461101 -- ----9/24/1980 911 ---- - - --120 --------USGS-380012121461101 -- ----4/21/1981 965 -7.5 -- - - --120 --------USGS-380012121461101 -- ----9/17/1981 976 -7.2 -- - - --130 --------USGS-380012121461101 -- ----4/29/1982 976 -7.2 -- - - --130 --------USGS-380012121461101 -- ----9/23/1982 1020 -7 -- - - --120 --------USGS-380012121461101 -- ----9/20/1972 843 ---- - - --81 --------USGS-380016121454501 -- ----11/15/1972 833 ---- - - --82 --------USGS-380016121454501 -- ----12/20/1972 853 ---- - - --87 --------USGS-380016121454501 -- ----1/25/1973 854 ---- - - --90 --------USGS-380016121454501 -- ----2/20/1973 902 ---- - - --96 --------USGS-380016121454501 -- ----3/21/1973 909 ---- - - --100 --------USGS-380016121454501 -- ----5/24/1973 865 ---- - - --90 --------USGS-380016121454501 -- ----10/4/1973 800 ---- - - --78 --------USGS-380016121454501 -- ----3/11/1974 842 ---- - - --84 --------USGS-380016121454501 -- ----9/24/1974 811 ---- - - --77 --------USGS-380016121454501 -- ----4/7/1975 825 ---- - - --79 --------USGS-380016121454501 -- ----9/17/1975 780 ---- - - --76 --------USGS-380016121454501 -- ----4/12/1976 789 ---- - - --77 --------USGS-380016121454501 -- ----9/15/1976 755 ---- - - --75 --------USGS-380016121454501 -- ----4/26/1977 787 ---- - - --77 --------USGS-380016121454501 -- ----9/13/1977 883 ---- - - --91 --------USGS-380016121454501 -- ----4/17/1978 847 ---- - - --100 --------USGS-380016121454501 -- ----9/25/1978 878 ---- - - --91 --------USGS-380016121454501 -- ----4/17/1979 876 ---- - - --99 --------USGS-380016121454501 -- ----9/24/1979 818 ---- - - --87 --------USGS-380016121454501 -- ----4/10/1980 867 ---- - - --83 --------USGS-380016121454501 -- ----9/24/1980 859 ---- - - --92 --------USGS-380016121454501 -- ----4/21/1981 820 -7.7 -- - - --85 --------USGS-380016121454501 -- ----9/17/1981 847 -7.9 -- - - --91 --------USGS-380016121454501 -- ----4/29/1982 896 -7.6 -- - - --110 --------USGS-380016121454501 -- ----9/24/1982 877 -7.5 -- - - --99 --------USGS-380016121454501 -- ----6/22/1972 3260 ---- - - --560 --------USGS-380017121443201 -- Thursday, September 3, 2020Page 32 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----7/19/1972 3250 ---- - - --620 --------USGS-380017121443201 -- ----8/23/1972 3240 ---- - - --600 --------USGS-380017121443201 -- ----9/20/1972 3220 ---- - - --620 --------USGS-380017121443201 -- ----11/15/1972 3100 ---- - - --670 --------USGS-380017121443201 -- ----12/20/1972 3250 ---- - - --630 --------USGS-380017121443201 -- ----1/25/1973 3270 ---- - - --700 --------USGS-380017121443201 -- ----2/20/1973 3220 ---- - - --640 --------USGS-380017121443201 -- ----3/21/1973 3190 ---- - - --630 --------USGS-380017121443201 -- ----5/24/1973 3100 ---- - - --630 --------USGS-380017121443201 -- ----10/4/1973 3140 ---- - - --610 --------USGS-380017121443201 -- ----3/11/1974 3090 ---- - - --630 --------USGS-380017121443201 -- ----9/24/1974 3190 ---- - - --590 --------USGS-380017121443201 -- ----4/7/1975 3090 ---- - - --580 --------USGS-380017121443201 -- ----9/16/1975 3160 ---- - - --590 --------USGS-380017121443201 -- ----4/12/1976 3180 ---- - - --640 --------USGS-380017121443201 -- ----9/15/1976 3120 ---- - - --640 --------USGS-380017121443201 -- ----4/26/1977 3160 ---- - - --570 --------USGS-380017121443201 -- ----9/13/1977 3170 ---- - - --530 --------USGS-380017121443201 -- ----4/17/1978 2850 ---- - - --500 --------USGS-380017121443201 -- ----9/25/1978 2970 ---- - - --490 --------USGS-380017121443201 -- ----4/17/1979 2980 ---- - - --510 --------USGS-380017121443201 -- ----9/25/1979 2690 ---- - - --210 --------USGS-380017121443201 -- ----9/24/1980 2660 ---- - - --600 --------USGS-380017121443201 -- ----4/21/1981 2810 -7.7 -- - - --39 --------USGS-380017121443201 -- ----6/22/1972 1280 ---- - - --190 --------USGS-380017121455901 -- ----7/19/1972 1270 ---- - - --190 --------USGS-380017121455901 -- ----8/23/1972 1290 ---- - - --190 --------USGS-380017121455901 -- ----9/20/1972 1290 ---- - - --190 --------USGS-380017121455901 -- ----11/15/1972 1310 ---- - - --200 --------USGS-380017121455901 -- ----2/20/1973 1430 ---- - - --220 --------USGS-380017121455901 -- ----3/21/1973 1370 ---- - - --210 --------USGS-380017121455901 -- ----10/4/1973 1230 ---- - - --190 --------USGS-380017121455901 -- ----3/11/1974 1330 ---- - - --210 --------USGS-380017121455901 -- ----9/24/1974 1260 ---- - - --190 --------USGS-380017121455901 -- ----4/7/1975 1410 ---- - - --220 --------USGS-380017121455901 -- ----9/17/1975 1280 ---- - - --200 --------USGS-380017121455901 -- ----4/12/1976 1360 ---- - - --220 --------USGS-380017121455901 -- ----9/15/1976 1220 ---- - - --190 --------USGS-380017121455901 -- ----4/26/1977 1270 ---- - - --190 --------USGS-380017121455901 -- ----9/13/1977 1270 ---- - - --180 --------USGS-380017121455901 -- ----4/17/1978 1330 ---- - - --210 --------USGS-380017121455901 -- ----9/25/1978 1240 ---- - - --170 --------USGS-380017121455901 -- Thursday, September 3, 2020Page 33 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----4/17/1979 1220 ---- - - --180 --------USGS-380017121455901 -- ----9/24/1979 1330 ---- - - --190 --------USGS-380017121455901 -- ----4/10/1980 1240 ---- - - --170 --------USGS-380017121455901 -- ----9/24/1980 1230 ---- - - --200 --------USGS-380017121455901 -- ----4/21/1981 1250 -7.7 -- - - --210 --------USGS-380017121455901 -- ----9/17/1981 2030 -7.6 -- - - --230 --------USGS-380017121455901 -- ----4/29/1982 1330 -7.4 -- - - --220 --------USGS-380017121455901 -- ----9/24/1982 1350 -7.4 -- - - --220 --------USGS-380017121455901 -- ----12/23/1970 1940 ---- - - --450 --------USGS-380019121464601 -- ----1/26/1971 2090 ---- - - --490 --------USGS-380019121464601 -- ----3/5/1971 1960 ---- - - --470 --------USGS-380019121464601 -- ----3/25/1971 1970 ---- - - --470 --------USGS-380019121464601 -- ----4/21/1971 2120 ---- - - --480 --------USGS-380019121464601 -- ----5/20/1971 2070 ---- - - --480 --------USGS-380019121464601 -- ----6/23/1971 2070 ---- - - --470 --------USGS-380019121464601 -- ----7/20/1971 1910 ---- - - --480 --------USGS-380019121464601 -- ----8/24/1971 1970 ---- - - --430 --------USGS-380019121464601 -- ----9/22/1971 2040 ---- - - --420 --------USGS-380019121464601 -- ----10/28/1971 2050 ---- - - --450 --------USGS-380019121464601 -- ----11/23/1971 2070 ---- - - --460 --------USGS-380019121464601 -- ----12/20/1971 2020 ---- - - --440 --------USGS-380019121464601 -- ----1/18/1972 2030 ---- - - --460 --------USGS-380019121464601 -- ----2/22/1972 2010 ---- - - --440 --------USGS-380019121464601 -- ----3/21/1972 1980 ---- - - --440 --------USGS-380019121464601 -- ----4/18/1972 1960 ---- - - --410 --------USGS-380019121464601 -- ----8/22/1972 1930 ---- - - --390 --------USGS-380019121464601 -- ----9/19/1972 1960 ---- - - --410 --------USGS-380019121464601 -- ----11/15/1972 1880 ---- - - --390 --------USGS-380019121464601 -- ----12/19/1972 1940 ---- - - --400 --------USGS-380019121464601 -- ----1/24/1973 1930 ---- - - --400 --------USGS-380019121464601 -- ----2/20/1973 1940 ---- - - --400 --------USGS-380019121464601 -- ----3/21/1973 1940 ---- - - --380 --------USGS-380019121464601 -- ----5/23/1973 1880 ---- - - --97 --------USGS-380019121464601 -- ----10/4/1973 1880 ---- - - --370 --------USGS-380019121464601 -- ----3/11/1974 1870 ---- - - --370 --------USGS-380019121464601 -- ----9/24/1974 1790 ---- - - --330 --------USGS-380019121464601 -- ----4/7/1975 1800 ---- - - --330 --------USGS-380019121464601 -- ----9/16/1975 1710 ---- - - --330 --------USGS-380019121464601 -- ----4/12/1976 1720 ---- - - --320 --------USGS-380019121464601 -- ----9/15/1976 1620 ---- - - --290 --------USGS-380019121464601 -- ----4/26/1977 1570 ---- - - --280 --------USGS-380019121464601 -- ----9/13/1977 1710 ---- - - --310 --------USGS-380019121464601 -- Thursday, September 3, 2020Page 34 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----4/17/1978 1680 ---- - - --320 --------USGS-380019121464601 -- ----9/25/1978 1730 ---- - - --300 --------USGS-380019121464601 -- ----4/17/1979 1700 ---- - - --313 --------USGS-380019121464601 -- ----9/24/1979 1640 ---- - - --310 --------USGS-380019121464601 -- ----4/10/1980 1690 ---- - - --270 --------USGS-380019121464601 -- ----9/24/1980 1560 ---- - - --310 --------USGS-380019121464601 -- ----4/21/1981 1570 -7.4 -- - - --280 --------USGS-380019121464601 -- ----9/17/1981 1590 -7.5 -- - - --280 --------USGS-380019121464601 -- ----4/29/1982 1650 -7.4 -- - - --270 --------USGS-380019121464601 -- ----9/23/1982 1610 -7.1 -- - - --270 --------USGS-380019121464601 -- ----1/25/1973 2450 ---- - - --380 --------USGS-380020121443901 -- ----2/20/1973 2520 ---- - - --380 --------USGS-380020121443901 -- ----3/21/1973 2650 ---- - - --400 --------USGS-380020121443901 -- ----10/4/1973 2530 ---- - - --340 --------USGS-380020121443901 -- ----3/11/1974 2550 ---- - - --370 --------USGS-380020121443901 -- ----9/24/1974 2340 ---- - - --280 --------USGS-380020121443901 -- ----4/7/1975 2300 ---- - - --270 --------USGS-380020121443901 -- ----9/16/1975 2230 ---- - - --270 --------USGS-380020121443901 -- ----4/12/1976 2210 ---- - - --270 --------USGS-380020121443901 -- ----9/15/1976 2150 ---- - - --270 --------USGS-380020121443901 -- ----4/26/1977 2220 ---- - - --260 --------USGS-380020121443901 -- ----9/13/1977 2190 ---- - - --250 --------USGS-380020121443901 -- ----4/17/1978 2470 ---- - - --390 --------USGS-380020121443901 -- ----9/25/1978 2140 ---- - - --260 --------USGS-380020121443901 -- ----4/17/1979 1970 ---- - - --260 --------USGS-380020121443901 -- ----9/24/1979 1960 ---- - - --250 --------USGS-380020121443901 -- ----4/10/1980 1820 ---- - - --240 --------USGS-380020121443901 -- ----9/24/1980 1980 ---- - - --250 --------USGS-380020121443901 -- ----4/21/1981 1860 -7.7 -- - - --250 --------USGS-380020121443901 -- ----9/17/1981 2140 -7.9 -- - - --250 --------USGS-380020121443901 -- ----4/28/1982 1640 -7.7 -- - - --240 --------USGS-380020121443901 -- ----9/24/1982 1690 -8 -- - - --240 --------USGS-380020121443901 -- ----1/27/1971 2910 ---- - - --380 --------USGS-380025121471101 -- ----3/5/1971 2950 ---- - - --400 --------USGS-380025121471101 -- ----3/25/1971 2960 ---- - - --400 --------USGS-380025121471101 -- ----4/20/1971 3220 ---- - - --470 --------USGS-380025121471101 -- ----4/22/1971 3190 ---- - - --440 --------USGS-380025121471101 -- ----5/20/1971 3200 ---- - - --420 --------USGS-380025121471101 -- ----6/23/1971 3200 ---- - - --420 --------USGS-380025121471101 -- ----7/21/1971 2960 ---- - - --420 --------USGS-380025121471101 -- ----8/26/1971 3190 ---- - - --420 --------USGS-380025121471101 -- ----9/21/1971 3200 ---- - - --410 --------USGS-380025121471101 -- Thursday, September 3, 2020Page 35 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----10/28/1971 3190 ---- - - --400 --------USGS-380025121471101 -- ----11/24/1971 3170 ---- - - --400 --------USGS-380025121471101 -- ----12/21/1971 3190 ---- - - --410 --------USGS-380025121471101 -- ----1/19/1972 3200 ---- - - --400 --------USGS-380025121471101 -- ----2/23/1972 3000 ---- - - --380 --------USGS-380025121471101 -- ----3/21/1972 3090 ---- - - --390 --------USGS-380025121471101 -- ----4/18/1972 3140 ---- - - --390 --------USGS-380025121471101 -- ----6/22/1972 3120 ---- - - --400 --------USGS-380025121471101 -- ----7/19/1972 3070 ---- - - --390 --------USGS-380025121471101 -- ----8/21/1972 3060 ---- - - --390 --------USGS-380025121471101 -- ----9/19/1972 3100 ---- - - --390 --------USGS-380025121471101 -- ----11/14/1972 2870 ---- - - --370 --------USGS-380025121471101 -- ----12/19/1972 3120 ---- - - --390 --------USGS-380025121471101 -- ----1/25/1973 2900 ---- - - --350 --------USGS-380025121471101 -- ----2/22/1973 2700 ---- - - --310 --------USGS-380025121471101 -- ----3/22/1973 2470 ---- - - --260 --------USGS-380025121471101 -- ----5/23/1973 2890 ---- - - --370 --------USGS-380025121471101 -- ----10/3/1973 2460 ---- - - --260 --------USGS-380025121471101 -- ----3/14/1974 2380 ---- - - --300 --------USGS-380025121471101 -- ----4/12/1976 2390 ---- - - --320 --------USGS-380025121471101 -- ----9/15/1976 2260 ---- - - --320 --------USGS-380025121471101 -- ----4/27/1977 2330 ---- - - --330 --------USGS-380025121471101 -- ----9/13/1977 2300 ---- - - --320 --------USGS-380025121471101 -- ----9/25/1978 2200 ---- - - --320 --------USGS-380025121471101 -- ----4/17/1979 2280 ---- - - --370 --------USGS-380025121471101 -- ----4/20/1981 2460 -7 -- - - --440 --------USGS-380025121471101 -- ----9/18/1981 1290 -7.2 -- - - --480 --------USGS-380025121471101 -- ----4/28/1982 2350 -7.4 -- - - --370 --------USGS-380025121471101 -- ----9/23/1982 2640 -7.1 -- - - --470 --------USGS-380025121471101 -- ND ---2/4/1957 1410 858 7.3 -65 51 160 4.3 110 220 330271 5.87 ----390USGS-380043121461201 -- ND ---8/19/1957 1490 918 8 -73 64 150 4.5 130 250 330271 5.42 ----560USGS-380043121461201 -- 0.2 ---8/12/1958 1620 960 8 -140 24 170 4.7 140 260 340279 4.97 -ND--550USGS-380043121461201 -- 0.5 ---7/8/1959 1560 907 7.9 -34 80 170 6 130 240 330271 5.2 ----560USGS-380043121461201 -- 0.4 ---7/14/1960 1590 974 8.1 -80 59 170 4.1 150 270 340279 5.2 ----630USGS-380043121461201 -- ND ---9/14/1960 1680 963 8 -85 58 180 4 140 280 320262 3.84 ----590USGS-380043121461201 -- 0.3 ---6/12/1961 1740 1030 8.1 -100 59 180 4.3 180 280 350287 4.97 ----660USGS-380043121461201 -- 0.3 ---6/8/1962 1830 1090 8.2 -85 68 200 4.4 200 300 350287 5.2 ----670USGS-380043121461201 -- 0.1 ---6/6/1963 1290 872 8.3 -60 54 180 4.8 140 240 290248 6.1 ----600USGS-380043121461201 -- ----6/24/1964 1480 872 8 -69 58 150 4.5 110 220 340279 8.81 ----400USGS-380043121461201 -- ----9/15/1966 1500 ---- - - --220 --7.23 -----USGS-380043121461201 -- ----8/23/1967 1540 ---- - - --220 --10.4 -----USGS-380043121461201 -- ----7/31/1968 1460 ---- - - --230 --10.6 -----USGS-380043121461201 -- Thursday, September 3, 2020Page 36 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----7/20/1972 1730 ---- - - --270 --------USGS-380043121461201 -- ----8/23/1972 1720 ---- - - --270 --------USGS-380043121461201 -- ----9/20/1972 1670 ---- - - --270 --------USGS-380043121461201 -- ----11/15/1972 1540 ---- - - --240 --------USGS-380043121461201 -- ----12/20/1972 1610 ---- - - --250 --------USGS-380043121461201 -- ----1/24/1973 1620 ---- - - --250 --------USGS-380043121461201 -- ----2/20/1973 1610 ---- - - --250 --------USGS-380043121461201 -- ----3/22/1973 1620 ---- - - --250 --------USGS-380043121461201 -- ----5/24/1973 1580 ---- - - --240 --------USGS-380043121461201 -- ----8/3/1973 1700 -7.6 -- -180 --260 330271 ------USGS-380043121461201 -- ----10/4/1973 1610 ---- - - --250 --------USGS-380043121461201 -- ----3/12/1974 1610 ---- - - --240 --------USGS-380043121461201 -- ----9/24/1974 1550 ---- - - --230 --------USGS-380043121461201 -- ----4/8/1975 1530 ---- - - --210 --------USGS-380043121461201 -- ----6/24/1975 1680 950 7.3 -77 55 160 4.9 140 220 330271 12.4 ----500USGS-380043121461201 -- ----9/17/1975 1530 ---- - - --220 --------USGS-380043121461201 -- ----4/14/1976 1570 ---- - - --240 --------USGS-380043121461201 -- ----9/16/1976 1520 ---- - - --230 --------USGS-380043121461201 -- ----4/26/1977 1530 ---- - - --220 --------USGS-380043121461201 -- ----7/20/1977 1550 -7.3 -- -160 --250 350287 ------USGS-380043121461201 -- ----9/13/1977 1560 ---- - - --220 --------USGS-380043121461201 -- ----9/25/1978 1630 ---- - - --230 --------USGS-380043121461201 -- ----4/17/1979 1650 ---- - - --240 --------USGS-380043121461201 -- ----9/24/1979 1630 ---- - - --250 --------USGS-380043121461201 -- ----4/10/1980 1740 ---- - - --230 --------USGS-380043121461201 -- ----9/26/1980 1680 ---- - - --260 --------USGS-380043121461201 -- ----4/20/1981 1690 -7 -- - - --240 --------USGS-380043121461201 -- ----9/17/1981 2130 -7.4 -- - - --360 --------USGS-380043121461201 -- ----4/28/1982 1750 -7.2 -- - - --240 --------USGS-380043121461201 -- ----9/24/1982 1730 -7.4 -- - - --240 --------USGS-380043121461201 -- ----4/19/1972 2530 ---- - - --480 --------USGS-380048121470701 -- ----6/22/1972 2480 ---- - - --490 --------USGS-380048121470701 -- ----7/19/1972 2460 ---- - - --480 --------USGS-380048121470701 -- ----8/22/1972 2380 ---- - - --480 --------USGS-380048121470701 -- ----9/19/1972 2330 ---- - - --470 --------USGS-380048121470701 -- ----11/14/1972 2230 ---- - - --440 --------USGS-380048121470701 -- ----12/19/1972 2300 ---- - - --440 --------USGS-380048121470701 -- ----1/24/1973 2220 ---- - - --430 --------USGS-380048121470701 -- ----2/22/1973 2200 ---- - - --430 --------USGS-380048121470701 -- ----3/21/1973 2330 ---- - - --450 --------USGS-380048121470701 -- ----5/23/1973 2320 ---- - - --430 --------USGS-380048121470701 -- ----10/3/1973 2260 ---- - - --400 --------USGS-380048121470701 -- Thursday, September 3, 2020Page 37 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Shallow ----3/11/1974 2340 ---- - - --420 --------USGS-380048121470701 -- ----9/25/1974 2380 ---- - - --410 --------USGS-380048121470701 -- ----4/8/1975 2470 ---- - - --490 --------USGS-380048121470701 -- ----9/16/1975 2150 ---- - - --400 --------USGS-380048121470701 -- ----4/12/1976 2340 ---- - - --370 --------USGS-380048121470701 -- ----9/15/1976 2500 ---- - - --450 --------USGS-380048121470701 -- ----4/27/1977 2490 ---- - - --450 --------USGS-380048121470701 -- ----4/20/1978 2860 ---- - - --370 --------USGS-380048121470701 -- ----9/25/1978 2420 ---- - - --320 --------USGS-380048121470701 -- ----9/24/1979 2240 ---- - - --300 --------USGS-380048121470701 -- ----4/10/1980 2030 ---- - - --250 --------USGS-380048121470701 -- ----9/24/1980 2270 ---- - - --380 --------USGS-380048121470701 -- ----4/21/1981 2160 -7.1 -- - - --410 --------USGS-380048121470701 -- ----9/17/1981 2710 -7.3 -- - - --500 --------USGS-380048121470701 -- Deep 0.2 2 --5/1/1979 900 588 7.8 10043 19 140 1.5 83 86 -270 ND -20-1402600USGS-375437121355601 -- 0.3 ---5/2/1979 1280 883 7.5 -- - - -180 160 -240 7.2 ----1500USGS-375600121410901 -- ----5/20/1971 2760 ---- - - --300 --------USGS-380019121473401 -- ----6/23/1971 2800 ---- - - --280 --------USGS-380019121473401 -- ----7/20/1971 2580 ---- - - --280 --------USGS-380019121473401 -- ----8/26/1971 2690 ---- - - --220 --------USGS-380019121473401 -- ----9/22/1971 2800 ---- - - --280 --------USGS-380019121473401 -- ----10/28/1971 2800 ---- - - --280 --------USGS-380019121473401 -- ----11/23/1971 2780 ---- - - --280 --------USGS-380019121473401 -- ----12/21/1971 2820 ---- - - --290 --------USGS-380019121473401 -- ----1/19/1972 2870 ---- - - --300 --------USGS-380019121473401 -- ----3/21/1972 2780 ---- - - --280 --------USGS-380019121473401 -- ----4/18/1972 2800 ---- - - --280 --------USGS-380019121473401 -- ----6/21/1972 2790 ---- - - --310 --------USGS-380019121473401 -- ----7/19/1972 2790 ---- - - --290 --------USGS-380019121473401 -- ----8/22/1972 2780 ---- - - --290 --------USGS-380019121473401 -- ----9/19/1972 2800 ---- - - --280 --------USGS-380019121473401 -- ----11/14/1972 2940 ---- - - --350 --------USGS-380019121473401 -- ----12/19/1972 3180 ---- - - --370 --------USGS-380019121473401 -- ----1/24/1973 3130 ---- - - --380 --------USGS-380019121473401 -- ----2/22/1973 2940 ---- - - --450 --------USGS-380019121473401 -- ----3/21/1973 2960 ---- - - --470 --------USGS-380019121473401 -- ----5/23/1973 2730 ---- - - --280 --------USGS-380019121473401 -- ----10/4/1973 2830 ---- - - --270 --------USGS-380019121473401 -- ----3/11/1974 2750 ---- - - --660 --------USGS-380019121473401 -- Thursday, September 3, 2020Page 38 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep ----9/24/1974 2820 ---- - - --260 --------USGS-380019121473401 -- ----4/7/1975 2810 ---- - - --270 --------USGS-380019121473401 -- ----9/16/1975 2830 ---- - - --550 --------USGS-380019121473401 -- ----9/16/1976 2740 ---- - - --260 --------USGS-380019121473401 -- ----4/27/1977 2920 ---- - - --240 --------USGS-380019121473401 -- ----9/13/1977 2830 ---- - - --250 --------USGS-380019121473401 -- ----4/21/1978 2640 ---- - - --230 --------USGS-380019121473401 -- ----9/25/1978 2720 ---- - - --590 --------USGS-380019121473401 -- ----4/17/1979 2590 ---- - - --240 --------USGS-380019121473401 -- ----9/24/1979 2440 ---- - - --90 --------USGS-380019121473401 -- ----4/11/1980 2450 ---- - - --190 --------USGS-380019121473401 -- ----9/24/1980 2330 ---- - - --220 --------USGS-380019121473401 -- ----4/20/1981 2500 -7.4 -- - - --250 --------USGS-380019121473401 -- ----9/17/1981 2470 -7.6 -- - - --440 --------USGS-380019121473401 -- ----4/28/1982 2520 -7.4 -- - - --220 --------USGS-380019121473401 -- ----9/23/1982 2690 -6.9 -- - - --580 --------USGS-380019121473401 -- ----12/23/1970 1900 ---- - - --110 --------USGS-380024121490801 -- ----1/27/1971 1940 ---- - - --110 --------USGS-380024121490801 -- ----3/4/1971 1910 ---- - - --100 --------USGS-380024121490801 -- ----3/25/1971 1920 ---- - - --100 --------USGS-380024121490801 -- ----4/21/1971 2020 ---- - - --120 --------USGS-380024121490801 -- ----5/20/1971 2020 ---- - - --110 --------USGS-380024121490801 -- ----6/23/1971 2000 ---- - - --110 --------USGS-380024121490801 -- ----7/21/1971 1860 ---- - - --120 --------USGS-380024121490801 -- ----8/25/1971 1890 ---- - - --80 --------USGS-380024121490801 -- ----9/21/1971 1980 ---- - - --100 --------USGS-380024121490801 -- ----10/28/1971 2000 ---- - - --100 --------USGS-380024121490801 -- ----11/23/1971 2030 ---- - - --110 --------USGS-380024121490801 -- ----12/20/1971 2080 ---- - - --110 --------USGS-380024121490801 -- ----1/18/1972 2120 ---- - - --120 --------USGS-380024121490801 -- ----2/22/1972 2080 ---- - - --120 --------USGS-380024121490801 -- ----3/21/1972 2050 ---- - - --110 --------USGS-380024121490801 -- ----4/19/1972 2010 ---- - - --110 --------USGS-380024121490801 -- ----6/21/1972 1990 ---- - - --110 --------USGS-380024121490801 -- ----7/18/1972 2000 ---- - - --110 --------USGS-380024121490801 -- ----8/22/1972 1970 ---- - - --110 --------USGS-380024121490801 -- ----9/19/1972 1980 ---- - - --100 --------USGS-380024121490801 -- ----11/14/1972 1960 ---- - - --110 --------USGS-380024121490801 -- ----12/19/1972 421 ---- - - --44 --------USGS-380024121490801 -- ----1/24/1973 2050 ---- - - --110 --------USGS-380024121490801 -- ----2/22/1973 2070 ---- - - --110 --------USGS-380024121490801 -- ----3/22/1973 2090 ---- - - --110 --------USGS-380024121490801 -- Thursday, September 3, 2020Page 39 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep ----5/23/1973 1970 ---- - - --110 --------USGS-380024121490801 -- ----10/3/1973 2020 ---- - - --95 --------USGS-380024121490801 -- ----3/11/1974 2060 ---- - - --120 --------USGS-380024121490801 -- ----9/24/1974 1960 ---- - - --110 --------USGS-380024121490801 -- ----4/8/1975 2060 ---- - - --100 --------USGS-380024121490801 -- ----9/17/1975 1930 ---- - - --100 --------USGS-380024121490801 -- ----4/13/1976 2000 ---- - - --110 --------USGS-380024121490801 -- ----9/13/1977 1910 ---- - - --100 --------USGS-380024121490803 -- ----4/20/1978 1980 ---- - - --110 --------USGS-380024121490803 -- ----9/25/1978 2010 ---- - - --97 --------USGS-380024121490803 -- ----4/17/1979 1950 ---- - - --114 --------USGS-380024121490803 -- ----9/24/1979 1880 ---- - - --110 --------USGS-380024121490803 -- ----4/10/1980 2030 ---- - - --100 --------USGS-380024121490803 -- ----9/24/1980 1920 ---- - - --120 --------USGS-380024121490803 -- ----4/21/1981 1990 -7.5 -- - - --120 --------USGS-380024121490803 -- ----9/17/1981 103 -7.4 -- - - --130 --------USGS-380024121490803 -- ----4/29/1982 1970 -7.4 -- - - --120 --------USGS-380024121490803 -- ----9/23/1982 1930 -7 -- - - --120 --------USGS-380024121490803 -- ----9/20/1972 2900 ---- - - --490 --------USGS-380048121460901 -- ----11/15/1972 2700 ---- - - --450 --------USGS-380048121460901 -- ----12/20/1972 2720 ---- - - --450 --------USGS-380048121460901 -- ----1/24/1973 2750 ---- - - --450 --------USGS-380048121460901 -- ----2/20/1973 2730 ---- - - --440 --------USGS-380048121460901 -- ----3/22/1973 2700 ---- - - --430 --------USGS-380048121460901 -- ----10/4/1973 2640 ---- - - --420 --------USGS-380048121460901 -- ----3/12/1974 2560 ---- - - --430 --------USGS-380048121460901 -- ----9/24/1974 2560 ---- - - --400 --------USGS-380048121460901 -- ----4/8/1975 2550 ---- - - --400 --------USGS-380048121460901 -- ----9/17/1975 2540 ---- - - --410 --------USGS-380048121460901 -- ----4/14/1976 3250 ---- - - --400 --------USGS-380048121460901 -- ----9/16/1976 2560 ---- - - --410 --------USGS-380048121460901 -- ----4/26/1977 2630 ---- - - --400 --------USGS-380048121460901 -- ----9/13/1977 2790 ---- - - --430 --------USGS-380048121460901 -- ----9/25/1978 2730 ---- - - --370 --------USGS-380048121460901 -- ----4/17/1979 3330 ---- - - --640 --------USGS-380048121460901 -- 0.0001 ---6/5/1979 1330 711 8.1 -63 35 140 3.8 73 200 -270 0.02 ----500USGS-380055121374001 -- ----4/19/1972 888 ---- - - --110 --------USGS-380102121480801 -- ----6/21/1972 605 ---- - - --100 --------USGS-380102121480801 -- ----7/20/1972 897 ---- - - --140 --------USGS-380102121480801 -- ----8/22/1972 1460 ---- - - --160 --------USGS-380102121480801 -- ----9/19/1972 1480 ---- - - --160 --------USGS-380102121480801 -- Thursday, September 3, 2020Page 40 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Deep ----11/14/1972 1440 ---- - - --160 --------USGS-380102121480801 -- ----5/23/1973 1080 ---- - - --120 --------USGS-380102121480801 -- ----10/3/1973 1500 ---- - - --160 --------USGS-380102121480801 -- ----3/11/1974 962 ---- - - --94 --------USGS-380102121480801 -- ----9/24/1974 1480 ---- - - --160 --------USGS-380102121480801 -- ----4/8/1975 1230 ---- - - --140 --------USGS-380102121480801 -- ----9/17/1975 573 ---- - - --96 --------USGS-380102121480801 -- ----4/12/1976 826 ---- - - --150 --------USGS-380102121480801 -- ----4/26/1977 1200 ---- - - --230 --------USGS-380102121480801 -- ----9/13/1977 1110 ---- - - --240 --------USGS-380102121480801 -- ----4/20/1978 1240 ---- - - --150 --------USGS-380102121480801 -- ----9/25/1978 1490 ---- - - --160 --------USGS-380102121480801 -- ----4/17/1979 1440 ---- - - --155 --------USGS-380102121480801 -- ----9/24/1979 876 ---- - - --200 --------USGS-380102121480801 -- ----4/10/1980 1360 ---- - - --140 --------USGS-380102121480801 -- ----9/25/1980 1620 ---- - - --210 --------USGS-380102121480801 -- 0.0001 1 --6/5/1979 2400 1324 7.9 10084 40 340 4.7 51 610 -190 0.02 -10-3201800USGS-380218121380901 -- Composite -1 490-7/18/1974 1120 610 7.9 -32 16 180 3.1 110 91 330282 0.023 ND 580-3002500USGS-375228121382001 -- ----6/15/1976 1000 -7.9 -- -170 --96 320262 ------USGS-375228121382001 -- 0.1 ---5/2/1979 916 561 7.7 -35 19 140 1.3 66 90 -300 ND ----2400USGS-375619121353001 -- Unknown 0.5 ---5/1/1979 -1080 --120 54 150 6.2 270 190 -250 37 ----70001N02E01F001M -- 1.2 1 --5/1/1979 -1600 --130 52 320 2.7 540 280 -220 24 -20-0.01240001N02E03K001M -- ----7/19/1974 1700 1090 7.9 -134 55 152 3.5 307 212 -246 48 ----110001N02E13H001M -- ----6/15/1976 1680 -7.9 -- -138 --194 -210 ------01N02E13H001M -- ----8/22/1978 1700 -8.2 -- -154 --210 -268 ------01N02E13H001M -- ----7/24/1980 1710 -8.5 -134 58 158 --210 -192 ------01N02E13H001M -- ----11/17/1982 1690 -7.7 -127 57 157 3.3 -211 -260 ------01N02E13H001M -- ----8/14/1984 1620 1050 8 -88 54 155 3.3 291 212 -201 -----120001N02E13H001M -- ----7/15/1988 841 -8.3 -60 30 85 --72 -189 ------01N02E13H001M -- ----6/15/1982 968 643 8 -70 33 97 3.2 131 85 -256 -----190001N02E24M001M -- ----6/15/1982 1450 891 8 -83 52 114 4.4 124 187 -282 -----210001N02E24R002M -- 0.2 1 --5/1/1979 -886 --98 54 110 1.8 130 170 -310 30 -10-0.14180001N02E25F001M -- ----11/19/1980 1270 -7.9 -99 52 110 --145 -282 -----140001N02E25G001M -- ----5/26/1981 1290 -8.1 -96 51 108 --148 -314 -----160001N02E25G001M -- Thursday, September 3, 2020Page 41 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown ----6/2/1982 1190 698 8.1 -59 46 104 1.5 126 128 -258 -----170001N02E25G001M -- ----11/19/1980 1740 -8 -137 66 140 --251 -274 -----130001N02E26H001M -- ----5/7/1981 1560 -8.2 -115 56 133 --232 -245 -----210001N02E26H001M -- 0.2 1 30-10/19/1987 1080 630 7.6 -75 34 110 2.4 150 94 -240 -1 6050 1-01N03E06N001M 1- 0.2 1 20-5/5/1988 986 660 7.6 -62 33 110 3.2 150 64 -230 -0.001 5030 0.01-01N03E06N002M 1- 0.2 1 --5/2/1979 -1070 --92 52 180 1.5 210 260 -250 21 -10-0.001200001N03E09E001M -- 0.1 ---5/2/1979 -604 --35 19 140 1.3 66 90 -300 100 ----240001N03E13C001M -- 0.4 -20-9/17/1981 1190 836 7.7 -98 53 99 -167 134 -246 --0.13-1-01N03E18D001M -- 0.3 ---5/2/1979 -885 --- - - -180 160 -240 32 ----150001N03E18G001M -- 0.2 1 --5/1/1979 -586 --43 19 140 1.5 83 86 -270 0.1 -20-0.14260001N03E25C001M -- ----11/20/1980 2120 -8.2 -47 46 378 --250 -521 -----840001N03E26C002M -- ----11/19/1980 2040 -8.3 -52 38 361 --208 -554 -----800001N03E27Q003M -- ----5/7/1981 2020 -8.4 -54 39 360 --210 -547 -----840001N03E27Q003M -- 0.6 ---5/1/1979 -1200 --94 70 180 1 190 330 -310 0.1 ----310001N03E27R001M -- ----11/19/1980 1560 -8.2 -92 38 194 --196 -360 -----300001N03E28Q001M -- ----5/26/1981 1580 -8.1 -91 39 193 --203 -362 -----300001N03E28Q001M -- ----11/19/1980 1400 -8.2 -107 44 130 --216 -272 -----260001N03E29Q001M -- ----5/7/1981 1360 -8.1 -105 43 128 2.2 -220 -232 -----280001N03E29Q001M -- ----6/2/1982 1360 825 7.9 -78 43 129 2.3 140 223 -226 -----290001N03E29Q001M -- 0.4 1 --5/2/1979 -1280 --100 68 260 2.1 180 260 -480 53 -30-1380001N03E30L001M -- ----11/19/1980 2040 -8.2 -105 70 248 --272 -498 -----340001N03E30L001M -- ----5/15/1981 2060 -8.2 -108 72 253 --295 -474 -----380001N03E30L001M -- ----6/14/1982 1910 1240 8.1 -86 69 202 2.7 154 272 -405 -----320001N03E30L002M -- ----6/14/1982 1670 1060 7.9 -97 51 193 3.1 139 244 -374 -----380001N03E30M001M -- ----11/19/1980 1390 -8.2 -60 36 207 --144 -381 -----410001N03E31C001M -- ----5/7/1981 1410 -8.4 -60 36 - --148 -399 -----450001N03E31C001M -- ----6/2/1982 1400 801 8.1 -31 35 212 1.8 134 150 -355 -----420001N03E31C001M -- ----11/18/1980 2340 ---164 54 256 --450 -323 -----320001N03E32C001M -- ----5/7/1981 2110 -8 -151 48 - --385 -331 -----330001N03E32C001M -- ----11/20/1980 1680 -8.2 -74 50 222 --270 -349 -----260001N03E33J001M -- ----5/15/1981 1610 -8.3 -72 48 - --260 -338 -----280001N03E33J001M -- ----6/10/1982 1620 968 8.1 -72 50 206 0.4 98 275 -326 -----280001N03E33J001M -- ----11/20/1980 1920 -8 -88 68 180 --346 -283 -----290001N03E34A001M -- Thursday, September 3, 2020Page 42 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown ----5/26/1981 1690 -8.3 -88 65 176 --280 -313 -----270001N03E34A001M -- ----6/2/1982 1660 1080 8.1 -73 65 176 1.4 170 291 -285 -----320001N03E34A001M -- ----11/20/1980 1440 -8.3 -46 37 230 --136 -458 -----340001N03E35N001M -- ----5/26/1981 1560 -8.4 -53 42 - --164 -465 -----320001N03E35N001M -- ----6/9/1982 1120 722 8.3 -29 14 206 2.2 119 128 -280 -----380001S03E02N001M -- ----11/5/1980 7790 -8 -252 140 - --2320 -356 -----1500001S03E02P001M -- ----5/5/1981 7420 -7.9 -240 149 - --2120 -363 -----1500001S03E02P001M -- ----6/10/1982 2060 1280 8.2 -50 140 305 0.6 190 260 -525 -----480001S03E03H001M -- -ND 490-7/18/1974 --8.4 -- - -3.1 114 91 -279 0.02 ND --300250001S03E03M001M -- ----6/15/1976 --8.3 -- - - --96 -258 ------01S03E03M001M -- ----8/22/1978 --8.5 -- - - --100 -287 ------01S03E03M001M -- ----7/24/1980 --8.8 -- - - --100 -279 ------01S03E03M001M -- ----11/4/1980 --8.5 --16 - --102 -281 ------01S03E03M001M -- ----5/6/1981 --8.4 --15 - --101 -280 ------01S03E03M001M -- ----11/17/1982 --8.1 --17 -2.2 -111 -287 ------01S03E03M001M -- ----8/14/1984 -691 8.4 --19 -2.2 157 - -246 -----310001S03E03M001M -- ----6/10/1982 -753 ---34 -0.7 90 146 -310 -----270001S03E03M002M -- ----6/10/1982 1190 753 8.1 -71 34 144 0.7 90 146 -310 -----270001S03E03M002M -- ----11/6/1980 1310 -8.3 -90 51 - --155 -333 -----200001S03E03N002M -- ----5/5/1981 1100 -8.3 -44 23 167 --112 -302 -----310001S03E03N002M -- ----11/6/1980 1030 -8.5 -28 12 - --98 -278 -----340001S03E03N003M -- ----5/5/1981 1020 -8.4 -28 12 184 --100 -279 -----340001S03E03N003M -- ----6/8/1982 1950 1250 7.9 -103 58 208 1.1 176 375 -285 -----290001S03E03P001M -- ----6/10/1982 2300 1470 8 -125 71 257 1 184 492 -286 -----320001S03E03Q001M -- ----6/10/1982 3450 2430 8 -138 113 439 0.7 412 738 -376 -----650001S03E03Q002M -- ----11/17/1980 848 -8.1 -56 24 90 1.7 -93 -219 -----190001S03E04Q001M -- ----5/26/1981 842 -8.2 -54 23 90 1.6 -90 -219 -----210001S03E04Q001M -- 0.3 ---6/5/1979 -642 --64 29 110 1.9 84 140 -270 -----190001S03E09A001M -- ----11/17/1980 1110 -8.2 -67 29 116 --152 -210 -----120001S03E09A002M -- ----5/5/1981 846 -8.2 -52 22 88 2 -120 -170 -----120001S03E09A002M -- ----6/8/1982 1200 773 8.2 -66 30 153 1.9 119 161 -265 -----280001S03E10C001M -- ----6/9/1982 2610 1750 8.1 -152 88 287 1.1 292 460 -416 -----420001S03E10C002M -- ----11/17/1980 2230 -8.2 -48 29 394 --321 -330 -----840001S03E10G001M -- ----5/5/1981 2260 -8.2 -51 74 - --330 -331 -----930001S03E10G001M -- Thursday, September 3, 2020Page 43 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown ----11/17/1980 623 -8.2 -34 19 72 2 -56 -200 -----50001S03E10K001M -- ----5/6/1981 715 -8.4 -39 22 80 2.1 -74 -215 -----60001S03E10K001M -- ----11/3/1980 1030 -8.5 -20 8 - --144 -238 -----230001S03E14D001M -- ----5/5/1981 1020 -8.2 -20 8 - --142 -236 -----220001S03E14D001M -- ----6/8/1982 4800 2980 8.3 -14 7 1060 6.3 170 1200 -563 -----3600001S03E14N001M -- ----8/9/1973 ----- 22 -5.5 160 697 -272 2.1 ----650001S03E15A001M -- ----6/24/1975 --8.1 -- - - --778 --------01S03E15A001M -- ----7/20/1977 --7.9 -- - - --1210 -224 ------01S03E15A001M -- ----8/3/1979 --8.5 -- - - --358 -274 ------01S03E15A001M -- ----11/3/1980 ----- 11 - --462 -239 -----420001S03E15A001M -- ----5/26/1981 --8.4 -- 8 - --308 -263 -----340001S03E15A001M -- ----8/3/1981 --8 -- 15 - --575 -249 ------01S03E15A001M -- ----6/8/1982 -1160 8.2 --12 - 3 106 419 -260 ------01S03E15A001M -- ----8/16/1983 -1060 8.1 --11 -2.8 102 363 -258 -----380001S03E15A001M -- ----8/1/1985 --8.6 --12 - --395 --------01S03E15A001M -- ----7/28/1987 ----- 10 - --- -261 ------01S03E15A001M -- ----9/14/1989 --8.4 -- 9 - --286 -262 ------01S03E15A001M -- ----11/4/1980 --8.5 -- - - --251 -288 ------01S03E22H001M -- ----11/4/1980 1460 -8.5 -24 23 - --251 -288 -----640001S03E22H001M -- ----5/6/1981 1280 -8.4 -19 18 - --205 -277 -----540001S03E22H001M -- ----11/4/1980 898 -8.4 -21 14 - --115 -236 -----310001S03E22H002M -- ----5/28/1981 853 -8.4 -20 14 - --99 -237 -----280001S03E22H002M -- ----11/5/1980 3310 -8.3 -49 43 - --858 -289 -----1400001S03E23E001M -- ----5/5/1981 3300 -8.1 -48 43 - --850 -283 -----1300001S03E23E001M -- ----11/5/1980 9450 -8.2 -29 44 - --2760 -781 -----8200001S03E23J001M -- ----5/5/1981 6570 -8.3 -11 16 - --1600 -847 -----6000001S03E23J001M -- ----11/3/1980 3420 -8 -145 99 - --875 -236 -----320001S03E26A001M -- ----5/27/1981 3460 -8.1 -150 104 - --912 -229 -----330001S03E26A001M -- ----4/12/1978 768 -7.8 -- -76 --77 -247 0.3 ----60001S04E09N002M -- ----10/17/1978 615 ---- - - --- --------01S04E09N002M -- ----4/17/1979 647 ---- - - --- --------01S04E09N002M -- ----10/16/1979 647 ---- - - --- --------01S04E09N002M -- ----4/9/1980 618 ---- - - --- --------01S04E09N002M -- ----11/24/1980 559 ---- - - --- -------50001S04E09N002M -- ----4/8/1981 532 ---- - - --- --------01S04E09N002M -- ----11/9/1981 564 ---- - - --- --------01S04E09N002M -- ----5/20/1982 574 ---- - - --- --------01S04E09N002M -- ----11/4/1980 2480 ---- - - --- --------01S04E17A001M -- Thursday, September 3, 2020Page 44 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown ----4/8/1981 4400 2910 7.4 -208 84 602 2.6 620 998 -209 -----500001S04E17A001M -- ----11/9/1981 2540 ---- - - --- -------420001S04E17A001M -- ----5/20/1982 696 ---- - - --- --------01S04E17A001M -- ----4/12/1978 5630 -8 -- -729 --1140 -393 16 ----630001S04E17A002M -- ----10/17/1978 6140 4310 8 -391 147 835 6.8 973 1350 -493 15 ----650001S04E17A002M -- ----4/17/1979 6350 ---- - - --- --------01S04E17A002M -- ----10/16/1979 2830 ---- - - --- -------360001S04E17A002M -- ----4/9/1980 5050 ---- - - --- -------720001S04E17A002M -- ----11/4/1980 1390 ---- - - --- --------01S04E17A002M -- ----4/8/1981 5080 ---- - - --- -------630001S04E17A002M -- ----11/9/1981 1440 ---- - - --- --------01S04E17A002M -- ----5/20/1982 6100 ---- - - --- --------01S04E17A002M -- ----4/12/1978 2260 -8 -- -208 --130 -161 2 ----260001S04E17C001M -- ----10/17/1978 1870 ---- - - --- --------01S04E17C001M -- ----4/17/1979 2400 ---- - - --- --------01S04E17C001M -- ----10/16/1979 1970 ---- - - --- --------01S04E17C001M -- ----4/9/1980 2140 1760 7.8 -243 52 190 1.4 848 147 -169 -----280001S04E17C001M -- ----11/4/1980 1950 ---- - - --- --------01S04E17C001M -- ----4/8/1981 2270 ---- - - --- --------01S04E17C001M -- ----11/9/1981 1620 ---- - - --- --------01S04E17C001M -- ----5/20/1982 1750 ---- - - --- --------01S04E17C001M -- ----4/12/1978 2750 ---- - - --499 --3.1 ----750001S04E20K001M -- ----10/17/1978 2640 ---- - - --- --------01S04E20K001M -- ----4/17/1979 2700 ---- - - --- --------01S04E20K001M -- ----10/15/1979 2530 1520 8.5 -52 31 461 3 220 487 -366 -----880001S04E20K001M -- ----4/9/1980 2500 ---- - - --- -------900001S04E20K001M -- ----11/25/1980 2470 ---- - - --- -------870001S04E20K001M -- ----4/8/1981 2360 ---- - - --- --------01S04E20K001M -- ----11/5/1981 2210 ---- - - --- --------01S04E20K001M -- ----5/20/1982 2170 ---- - - --- --------01S04E20K001M -- ----8/3/1973 1650 -8.1 -- -176 --258 -272 ------02N02E20A001M -- ----6/24/1975 1520 950 8.2 -77 55 158 4.9 144 215 -269 55 ----50002N02E20A001M -- ----7/20/1977 1560 -8 -- -156 --250 -287 ------02N02E20A001M -- ----8/3/1979 1650 -8.5 -88 62 174 --241 -282 ------02N02E20A001M -- ----8/3/1981 1730 -7.8 -86 62 187 --233 -284 ------02N02E20A001M -- ----8/16/1983 1640 -8.2 -80 58 180 --219 -275 ------02N02E20A001M -- ----7/25/1985 1650 1070 8.4 -87 64 198 5.2 218 208 -274 -----70002N02E20A001M -- ----9/14/1989 1570 -8.2 -77 56 174 4.2 -182 -280 ------02N02E20A001M -- 0.2 ---6/5/1979 -931 --150 60 95 4.3 69 320 -310 -----20002N02E36M001M -- 100 1 --6/5/1979 -1320 --84 40 340 47 51 610 -190 0.1 -90-0.32180002N03E10D001M -- Thursday, September 3, 2020Page 45 of 46{R_WaterQualitySummary} Cr (VI) (μg/L) 1000 50900 500 10 2250 2506.5/8.5 10 1000 1000 50 1.3 300 50 5000 (μg/L) Mn (μg/L) Summary of Groundwater Quality Laboratory Results - Other Wells (DWR/Environmental/USGS) Well Name Date EC TDS pH AlCaMgNa K SO Cl HCO Total Alkalinity NO F As Cr Cu Fe Cations Anions Trace Elements B (μmho/cm) Ba Se Zn (mg/L)(mg/L) (mg/L)(mg/L) (mg/L) (mg/L) (mg/L) (mg/L) (mg/L)(mg/L)(mg/L)(μg/L) (ug/L) (ug/L) (μg/L)(mg/L) (ug/L)(μg/L) (ug/L) 3 1 3 11 4 b b b b b ba a a aa a aabca 2 Unknown 0.1 ---6/5/1979 -768 --63 35 140 3.8 73 200 -270 -----50002N03E15Q001M -- 0.1 1 --6/5/1979 -1260 --140 82 150 3.2 310 170 -360 93 -1-0.3170002N03E29M001M -- ----4/7/1975 2890 ---- - - --360 --------USGS-380024121471501 -- ----9/16/1975 2810 ---- - - --380 --------USGS-380024121471501 -- ----4/21/1978 2860 ---- - - --400 --------USGS-380024121471501 -- ----9/25/1979 2770 ---- - - --- --------USGS-380024121471501 -- ----4/10/1980 2930 ---- - - --360 --------USGS-380024121471501 -- ----9/24/1980 2670 ---- - - --430 --------USGS-380024121471501 -- ----4/20/1981 2730 -7.4 -- - - --430 --------USGS-380024121471501 -- ----9/18/1981 2680 -7.4 -- - - --260 --------USGS-380024121471501 -- ----4/28/1982 2630 -7.3 -- - - --460 --------USGS-380024121471501 -- ----9/23/1982 2550 -7 -- - - --380 --------USGS-380024121471501 -- c) California State Notification Level "-" Not Analyzed; ND = Non-Detect (Reporting Limit unknown) For repeated sampling within a day, the maximum result for each constituent for the day is shown Bold indicates value exceeds Water Quality Limit 1. HCO3 and Total Alkalinity reported as CaCO3; NO3 reported as N a) Primary Drinking Water Standards for California and Federal Maximum Contaminant Levels b) Secondary Drinking Water Standards for California and Federal Maximum Contaminant Levels 2 Samples were filtered in the field Thursday, September 3, 2020Page 46 of 46{R_WaterQualitySummary} Groundwater Quality Graphs (TDS, EC, Cl, NO3, As) APPENDIX 3g Total Dissolved Solids Graphs 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:BG-1 Zone:Shallow Screened Int.:40-55Well Depth:55 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:BG-2 Zone:Shallow Screened Int.:22.5-37.5Well Depth:37.5 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:BG-3 Zone:Shallow Screened Int.:20-35Well Depth:35 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 11000 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:SL186102968-7EW-4 Zone:Shallow Screened Int.:Well Depth: {R_WQ_TDSplots} 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:SL186102968-7MW-1 Zone:Shallow Screened Int.:Well Depth: 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:SL186102968-7MW-11 Zone:Shallow Screened Int.:Well Depth: 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:SL186102968-7MW-12 Zone:Shallow Screened Int.:Well Depth: 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:SL186102968-7MW-13 Zone:Shallow Screened Int.:Well Depth: {R_WQ_TDSplots} 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:SL186102968-7MW-14 Zone:Shallow Screened Int.:Well Depth: 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:SL186102968-7MW-6 Zone:Shallow Screened Int.:Well Depth: 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:SL186102968-7MW-8 Zone:Shallow Screened Int.:Well Depth: 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:SL186102968-7MW-9 Zone:Shallow Screened Int.:Well Depth: {R_WQ_TDSplots} 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:USGS-380043121461201 Zone:Shallow Screened Int.:Well Depth:67 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 06 Zone:Deep Screened Int.:250-300Well Depth:305 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 07 Zone:Deep Screened Int.:265-295Well Depth:300 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 08 Zone:Deep Screened Int.:225-315Well Depth:325 {R_WQ_TDSplots} 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 09 Zone:Deep Screened Int.:210-230Well Depth:230 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 11 Zone:Deep Screened Int.:255-365Well Depth: 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 12 Zone:Deep Screened Int.:350-380, 430-450Well Depth:610 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 13 Zone:Deep Screened Int.:350-380, 430-480Well Depth:510 {R_WQ_TDSplots} 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 14 Zone:Deep Screened Int.:285-315Well Depth:340 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 15 Zone:Deep Screened Int.:239-259,289-324Well Depth:345 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:TOWN OF DISCOVERY BAY-WELL 01B Zone:Deep Screened Int.:271-289, 308-340Well Depth:350 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:TOWN OF DISCOVERY BAY-WELL 02 Zone:Deep Screened Int.:245-335Well Depth:348 {R_WQ_TDSplots} 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:TOWN OF DISCOVERY BAY-WELL 04A Zone:Deep Screened Int.:307-347Well Depth:357 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:TOWN OF DISCOVERY BAY-WELL 05A Zone:Deep Screened Int.:251-281, 307-347Well Depth:357 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 10A Zone:Composite Screened Int.:52-72, 135-182Well Depth:210 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:DIABLO WATER DISTRICT-WELL 01 - STANDBY Zone:Composite Screened Int.:100-170Well Depth:170 {R_WQ_TDSplots} 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:DELTA MUTUAL WATER COMPANY-East Well Zone:Unknown Screened Int.:Well Depth: 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:DELTA MUTUAL WATER COMPANY-West Well Zone:Unknown Screened Int.:Well Depth: 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:PLEASANTIMES MUTUAL WATER CO-WELL 2 - 4520 STONE Zone:Unknown Screened Int.:Well Depth: 0 200 400 600 800 1000 1200 1400 1600 1800 1950 1960 1970 1980 1990 2000 2010 2020TDS Concentration (mg/L) WellID:RIVERVIEW WATER ASSOCIATION-WELL 1 BEACON HARBOR Zone:Unknown Screened Int.:Well Depth: {R_WQ_TDSplots} Electrical Conductivity Graphs 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:5 Binn Zone:Shallow Screened Int.:Well Depth:45 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:BG-1 Zone:Shallow Screened Int.:40-55Well Depth:55 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:BG-2 Zone:Shallow Screened Int.:22.5-37.5Well Depth:37.5 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:BG-3 Zone:Shallow Screened Int.:20-35Well Depth:35 {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:01N03E17E001M Zone:Shallow Screened Int.:113-123Well Depth:123 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380012121461101 Zone:Shallow Screened Int.:Well Depth:95 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380016121454501 Zone:Shallow Screened Int.:Well Depth:140 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380017121443201 Zone:Shallow Screened Int.:Well Depth:82 {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380017121455901 Zone:Shallow Screened Int.:Well Depth:120 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380019121464601 Zone:Shallow Screened Int.:Well Depth:93 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380020121443901 Zone:Shallow Screened Int.:Well Depth:66 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380025121471101 Zone:Shallow Screened Int.:Well Depth:78 {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380043121461201 Zone:Shallow Screened Int.:Well Depth:67 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380048121470701 Zone:Shallow Screened Int.:Well Depth:165 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CITY OF BRENTWOOD-Well 06 Zone:Deep Screened Int.:250-300Well Depth:305 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CITY OF BRENTWOOD-Well 07 Zone:Deep Screened Int.:265-295Well Depth:300 {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CITY OF BRENTWOOD-Well 08 Zone:Deep Screened Int.:225-315Well Depth:325 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CITY OF BRENTWOOD-Well 11 Zone:Deep Screened Int.:255-365Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CITY OF BRENTWOOD-Well 12 Zone:Deep Screened Int.:350-380, 430-450Well Depth:610 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CITY OF BRENTWOOD-Well 13 Zone:Deep Screened Int.:350-380, 430-480Well Depth:510 {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CITY OF BRENTWOOD-Well 14 Zone:Deep Screened Int.:285-315Well Depth:340 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CITY OF BRENTWOOD-Well 09 Zone:Deep Screened Int.:210-230Well Depth:230 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CITY OF BRENTWOOD-Well 15 Zone:Deep Screened Int.:239-259,289-324Well Depth:345 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:DIABLO WATER DISTRICT-Glen Park Well Zone:Deep Screened Int.:230-245, 260-300Well Depth:315 {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:DIABLO WATER DISTRICT-Stonecreek PW Zone:Deep Screened Int.:220-295Well Depth:305 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:TOWN OF DISCOVERY BAY-WELL 02 Zone:Deep Screened Int.:245-335Well Depth:348 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:TOWN OF DISCOVERY BAY-WELL 05A Zone:Deep Screened Int.:251-281, 307-347Well Depth:357 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:TOWN OF DISCOVERY BAY-WELL 04A Zone:Deep Screened Int.:307-347Well Depth:357 {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:TOWN OF DISCOVERY BAY-WELL 01B Zone:Deep Screened Int.:271-289, 308-340Well Depth:350 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:TOWN OF DISCOVERY BAY-WELL 06 Zone:Deep Screened Int.:270-295, 305-350Well Depth:360 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:WILLOW PARK MARINA-West Well Zone:Deep Screened Int.:250-310Well Depth:340 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:WILLOW MOBILE HOME PARK-Well Head Zone:Deep Screened Int.:292-332Well Depth:410 {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380019121473401 Zone:Deep Screened Int.:Well Depth:190 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380024121490801 Zone:Deep Screened Int.:Well Depth:124 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380024121490803 Zone:Deep Screened Int.:Well Depth:140 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380048121460901 Zone:Deep Screened Int.:Well Depth:500 {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380102121480801 Zone:Deep Screened Int.:Well Depth:258 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CITY OF BRENTWOOD-Well 10A Zone:Composite Screened Int.:52-72, 135-182Well Depth:210 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:DIABLO WATER DISTRICT-WELL 01 - STANDBY Zone:Composite Screened Int.:100-170Well Depth:170 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:6 Byer Zone:Composite Screened Int.:Well Depth:185 {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:TOWN OF DISCOVERY BAY-WELL 03 - INACTIVE Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:01N02E13H001M Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:01S04E09N002M Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:01S04E17A001M Zone:Unknown Screened Int.:Well Depth: {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:01S04E17A002M Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:01S04E17C001M Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:01S04E20K001M Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:02N02E20A001M Zone:Unknown Screened Int.:Well Depth: {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:LOS VAQUEROS MARINA BLDG-SOURCE Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:LOS VAQUEROS INTERPRETIVE CENTER-SOURCE Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:FARRAR PARK PROPERTY OWNERS-Well Head Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:ANGLER S RANCH #3-WELL 02 Zone:Unknown Screened Int.:Well Depth: {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:DUTCH SLOUGH WATER WORKS-Well Head Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:ORWOOD RESORT-WELL 2 - WEST WELL Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:ANGLERS SUBDIVISION 4-WELL 1 - 1696 Taylor Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:ANGLERS SUBDIVISION 4-WELL 2 - 1398 Taylor Zone:Unknown Screened Int.:Well Depth: {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:ANGLERS SUBDIVISION 4-WELL 3 - 1698 Taylor Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:DELTA MUTUAL WATER COMPANY-East Well Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:DELTA MUTUAL WATER COMPANY-West Well Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:SANTIAGO ISLAND VILLAGE-WELL 01 Zone:Unknown Screened Int.:Well Depth: {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:PLEASANTIMES MUTUAL WATER CO-Well 1 - 4282 STONE Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:PLEASANTIMES MUTUAL WATER CO-WELL 2 - 4520 STONE Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:PLEASANTIMES MUTUAL WATER CO-WELL 3 - 4441 WILLOW Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:RIVERVIEW WATER ASSOCIATION-WELL 1 BEACON HARBOR Zone:Unknown Screened Int.:Well Depth: {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:RIVERVIEW WATER ASSOCIATION-WELL 2 END OF WILLOW RD Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:BIG OAK MOBILE HOME PARK WATER-Well Head - West well Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:BIG OAK MOBILE HOME PARK WATER-Wellhead- East well Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:SANDY POINT MOBILE HOME PARK-Well Head Zone:Unknown Screened Int.:Well Depth: {R_WQ_TDSplots} 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:CAMINO MOBILEHOME-WELL Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:RUSSOS MOBILE PARK-Well Head Zone:Unknown Screened Int.:Well Depth: 0 500 1000 1500 2000 2500 3000 3500 4000 4500 1950 1960 1970 1980 1990 2000 2010 2020Electrical Conductivity (µmhos/cm) WellID:USGS-380024121471501 Zone:Unknown Screened Int.:Well Depth: {R_WQ_TDSplots} Chloride Graphs 0 200 400 600 800 1000 1200 1400 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: 5 Binn Zone: Shallow Screened Int.Well Depth:45 0 200 400 600 800 1000 1200 1400 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: BG-1 Zone: Shallow Screened Int.40-55Well Depth:55 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:BG-2 Zone:Shallow Screened Int.22.5-37.5Well Depth:37.5 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:BG-3 Zone:Shallow Screened Int.20-35Well Depth:35 {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: 01N03E17E001M Zone: Shallow Screened Int.113-123Well Depth:123 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: SL186102968-7EW-4 Zone: Shallow Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:SL186102968-7MW-1 Zone:Shallow Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:SL186102968-7MW-11 Zone:Shallow Screened Int.Well Depth: {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: SL186102968-7MW-12 Zone: Shallow Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: SL186102968-7MW-13 Zone: Shallow Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:SL186102968-7MW-14 Zone:Shallow Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:SL186102968-7MW-6 Zone:Shallow Screened Int.Well Depth: {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: SL186102968-7MW-8 Zone: Shallow Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: SL186102968-7MW-9 Zone: Shallow Screened Int.Well Depth: 0 200 400 600 800 1000 1200 1400 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:SL205032990-W-04 Zone:Shallow Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:SL205032990-W-05 Zone:Shallow Screened Int.Well Depth: {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: SL205032990-W-07 Zone: Shallow Screened Int.Well Depth: 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: SL205032990-W-28 Zone: Shallow Screened Int.Well Depth: 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:T10000000655-MW.05 Zone:Shallow Screened Int.Well Depth: 0 200 400 600 800 1000 1200 1400 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:T10000000655-MW.06 Zone:Shallow Screened Int.Well Depth: {R_WQ_CLplots} 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: T10000000655-MW.07 Zone: Shallow Screened Int.Well Depth: 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: T10000000655-MW.08 Zone: Shallow Screened Int.Well Depth: 0 200 400 600 800 1000 1200 1400 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:T10000000655-MW.09 Zone:Shallow Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:USGS-380012121461101 Zone:Shallow Screened Int.Well Depth:95 {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: USGS-380016121454501 Zone: Shallow Screened Int.Well Depth:140 0 200 400 600 800 1000 1200 1400 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: USGS-380017121443201 Zone: Shallow Screened Int.Well Depth:82 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:USGS-380017121455901 Zone:Shallow Screened Int.Well Depth:120 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:USGS-380019121464601 Zone:Shallow Screened Int.Well Depth:93 {R_WQ_CLplots} 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: USGS-380020121443901 Zone: Shallow Screened Int.Well Depth:66 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: USGS-380025121471101 Zone: Shallow Screened Int.Well Depth:78 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:USGS-380043121461201 Zone:Shallow Screened Int.Well Depth:67 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:USGS-380048121470701 Zone:Shallow Screened Int.Well Depth:165 {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: CITY OF BRENTWOOD-Well 06 Zone: Deep Screened Int.250-300Well Depth:305 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: CITY OF BRENTWOOD-Well 07 Zone: Deep Screened Int.265-295Well Depth:300 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 08 Zone:Deep Screened Int.225-315Well Depth:325 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 11 Zone:Deep Screened Int.255-365Well Depth: {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: CITY OF BRENTWOOD-Well 12 Zone: Deep Screened Int.350-380, 430-450Well Depth:610 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: CITY OF BRENTWOOD-Well 13 Zone: Deep Screened Int.350-380, 430-480Well Depth:510 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 14 Zone:Deep Screened Int.285-315Well Depth:340 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 09 Zone:Deep Screened Int.210-230Well Depth:230 {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: CITY OF BRENTWOOD-Well 15 Zone: Deep Screened Int.239-259,289-324Well Depth:345 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: DIABLO WATER DISTRICT-Glen Park Well Zone: Deep Screened Int.230-245, 260-300Well Depth:315 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:TOWN OF DISCOVERY BAY-WELL 02 Zone:Deep Screened Int.245-335Well Depth:348 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:TOWN OF DISCOVERY BAY-WELL 05A Zone:Deep Screened Int.251-281, 307-347Well Depth:357 {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: TOWN OF DISCOVERY BAY-WELL 04A Zone: Deep Screened Int.307-347Well Depth:357 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: TOWN OF DISCOVERY BAY-WELL 01B Zone: Deep Screened Int.271-289, 308-340Well Depth:350 0 200 400 600 800 1000 1200 1400 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:USGS-380019121473401 Zone:Deep Screened Int.Well Depth:190 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:USGS-380024121490801 Zone:Deep Screened Int.Well Depth:124 {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: USGS-380024121490803 Zone: Deep Screened Int.Well Depth:140 0 200 400 600 800 1000 1200 1400 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: USGS-380048121460901 Zone: Deep Screened Int.Well Depth:500 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:USGS-380102121480801 Zone:Deep Screened Int.Well Depth:258 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 10A Zone:Composite Screened Int.52-72, 135-182Well Depth:210 {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: DIABLO WATER DISTRICT-WELL 01 - STANDBY Zone: Composite Screened Int.100-170Well Depth:170 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: 6 Byer Zone: Composite Screened Int.Well Depth:185 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:01N02E13H001M Zone:Unknown Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:01S03E03M001M Zone:Unknown Screened Int.Well Depth: {R_WQ_CLplots} 0 200 400 600 800 1000 1200 1400 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: 01S03E15A001M Zone: Unknown Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: 02N02E20A001M Zone: Unknown Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:LOS VAQUEROS MARINA BLDG-SOURCE Zone:Unknown Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:LOS VAQUEROS INTERPRETIVE CENTER-SOURCE Zone:Unknown Screened Int.Well Depth: {R_WQ_CLplots} 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: DUTCH SLOUGH WATER WORKS-Well Head Zone: Unknown Screened Int.Well Depth: 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: ANGLERS SUBDIVISION 4-WELL 2 - 1398 Taylor Zone: Unknown Screened Int.Well Depth: 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:ANGLERS SUBDIVISION 4-WELL 3 - 1698 Taylor Zone:Unknown Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:DELTA MUTUAL WATER COMPANY-East Well Zone:Unknown Screened Int.Well Depth: {R_WQ_CLplots} 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: SANTIAGO ISLAND VILLAGE-WELL 01 Zone: Unknown Screened Int.Well Depth: 0 50 100 150 200 250 300 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: PLEASANTIMES MUTUAL WATER CO-Well 1 - 4282 STONE Zone: Unknown Screened Int.Well Depth: 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:PLEASANTIMES MUTUAL WATER CO-WELL 2 - 4520 STONE Zone:Unknown Screened Int.Well Depth: 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:PLEASANTIMES MUTUAL WATER CO-WELL 3 - 4441 WILLOW Zone:Unknown Screened Int.Well Depth: {R_WQ_CLplots} 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: RIVERVIEW WATER ASSOCIATION-WELL 1 BEACON HARBOR Zone: Unknown Screened Int.Well Depth: 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID: RIVERVIEW WATER ASSOCIATION-WELL 2 END OF WILLOW RD Zone: Unknown Screened Int.Well Depth: 0 100 200 300 400 500 600 1950 1960 1970 1980 1990 2000 2010 2020Chloride Concentration (mg/L) WellID:USGS-380024121471501 Zone:Unknown Screened Int.Well Depth: {R_WQ_CLplots} Nitrate-N Graphs 10 16 22 28 34 40 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BG-1 Zone: Shallow Screened Int.40-55Well Depth:55 0 14 28 42 56 70 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BG-2 Zone: Shallow Screened Int.22.5-37.5Well Depth:37.5 0 8 16 24 32 40 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:BG-3 Zone:Shallow Screened Int.20-35Well Depth:35 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:BALDOCCHI WATER SYSTEM-Well Head Zone:Shallow Screened Int.100-110Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SL186102968-7EW-4 Zone: Shallow Screened Int.Well Depth: 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SL186102968-7MW-1 Zone: Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SL186102968-7MW-11 Zone:Shallow Screened Int.Well Depth: 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SL186102968-7MW-12 Zone:Shallow Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SL186102968-7MW-13 Zone: Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SL186102968-7MW-14 Zone: Shallow Screened Int.Well Depth: 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SL186102968-7MW-6 Zone:Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SL186102968-7MW-8 Zone:Shallow Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SL186102968-7MW-9 Zone: Shallow Screened Int.Well Depth: 0 300 600 900 1200 1500 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SL205032990-W-04 Zone: Shallow Screened Int.Well Depth: 0 18 36 54 72 90 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SL205032990-W-05 Zone:Shallow Screened Int.Well Depth: 0 6 12 18 24 30 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SL205032990-W-07 Zone:Shallow Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SL205032990-W-28 Zone: Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SL205092993-MW-14A Zone: Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SL205092993-MW-18A Zone:Shallow Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SL205092993-MW-5A Zone:Shallow Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SL205092993-MW-8A Zone: Shallow Screened Int.Well Depth: 0 10 20 30 40 50 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: T0601300766-MW5 Zone: Shallow Screened Int.Well Depth: 0 6 12 18 24 30 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:T0601300766-MW8B Zone:Shallow Screened Int.Well Depth: 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:T0601300766-MW8C Zone:Shallow Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: T10000000655-MW.05 Zone: Shallow Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: T10000000655-MW.06 Zone: Shallow Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:T10000000655-MW.07 Zone:Shallow Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:T10000000655-MW.08 Zone:Shallow Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: T10000000655-MW.09 Zone: Shallow Screened Int.Well Depth: 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: USGS-380043121461201 Zone: Shallow Screened Int.Well Depth:67 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 06 Zone:Deep Screened Int.250-300Well Depth:305 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 07 Zone:Deep Screened Int.265-295Well Depth:300 {R_WQ_NO3plots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: CITY OF BRENTWOOD-Well 08 Zone: Deep Screened Int.225-315Well Depth:325 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: CITY OF BRENTWOOD-Well 11 Zone: Deep Screened Int.255-365Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 12 Zone:Deep Screened Int.350-380, 430-450Well Depth:610 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 13 Zone:Deep Screened Int.350-380, 430-480Well Depth:510 {R_WQ_NO3plots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: CITY OF BRENTWOOD-Well 14 Zone: Deep Screened Int.285-315Well Depth:340 0 6 12 18 24 30 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: CITY OF BRENTWOOD-Well 09 Zone: Deep Screened Int.210-230Well Depth:230 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:CITY OF BRENTWOOD-Well 15 Zone:Deep Screened Int.239-259,289-324Well Depth:345 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:DIABLO WATER DISTRICT-Glen Park Well Zone:Deep Screened Int.230-245, 260-300Well Depth:315 {R_WQ_NO3plots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: DIABLO WATER DISTRICT-Stonecreek PW Zone: Deep Screened Int.220-295Well Depth:305 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: TOWN OF DISCOVERY BAY-WELL 02 Zone: Deep Screened Int.245-335Well Depth:348 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:TOWN OF DISCOVERY BAY-WELL 05A Zone:Deep Screened Int.251-281, 307-347Well Depth:357 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:TOWN OF DISCOVERY BAY-WELL 04A Zone:Deep Screened Int.307-347Well Depth:357 {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: TOWN OF DISCOVERY BAY-WELL 01B Zone: Deep Screened Int.271-289, 308-340Well Depth:350 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: TOWN OF DISCOVERY BAY-WELL 06 Zone: Deep Screened Int.270-295, 305-350Well Depth:360 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:KNIGHTSEN ELEMENTARY SCHOOL-WELL 3 Zone:Deep Screened Int.395-415Well Depth:415 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:WILLOW PARK MARINA-East Well Zone:Deep Screened Int.250-310Well Depth:400 {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: WILLOW PARK MARINA-West Well Zone: Deep Screened Int.250-310Well Depth:340 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: KNIGHTSEN COMMUNITY WATER SYSTEM-Well Head Zone: Deep Screened Int.235-255, 275-295Well Depth:305 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:Bethel Island (Sugar Barge Marina-Well Head) Zone:Deep Screened Int.317-333Well Depth:333 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:WILLOW MOBILE HOME PARK-Well Head Zone:Deep Screened Int.292-332Well Depth:410 {R_WQ_NO3plots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: CITY OF BRENTWOOD-Well 10A Zone: Composite Screened Int.52-72, 135-182Well Depth:210 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: DIABLO WATER DISTRICT-WELL 01 - STANDBY Zone: Composite Screened Int.100-170Well Depth:170 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:KNIGHTSEN ELEMENTARY SCHOOL-NORTH WELL Zone:Composite Screened Int.167-191, 210-230Well Depth:230 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:KNIGHTSEN ELEMENTARY SCHOOL-SOUTH WELL Zone:Composite Screened Int.167-191, 210-230Well Depth:230 {R_WQ_NO3plots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BRENTWOOD MISSIONARY BAPTIST-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: TOWN OF DISCOVERY BAY-WELL 03 - INACTIVE Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:HOLY CROSS CEMETERY-Well Head Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:OAKLEY MUTUAL WATER COMPANY-NORTH WELL - 4384 SANDMOUND Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: OAKLEY MUTUAL WATER COMPANY-SOUTH WELL - 4508 SANDMOUND Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: FARRAR PARK PROPERTY OWNERS-Well Head Zone: Unknown Screened Int.Well Depth: 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:VILLA DE GUADALUPE-WELL Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:PARK MARINA-Well Head Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: NEW DOCS MARINA-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: CRUISER HAVEN MARINA-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:BYRON UNITED METHODIST-WELL HEAD Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:EXCELSIOR MIDDLE SCHOOL-Well Head Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: MARINER COVE MARINA-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: GENOS DELI STATION-Well Head Zone: Unknown Screened Int.Well Depth: 0 6 12 18 24 30 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:BETHEL MISSIONARY BAPTIST-Well Head Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:HOLLAND RIVERSIDE MARINA-Well Head - West Well Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: HOLLAND RIVERSIDE MARINA-well 2 - East Well Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BETHEL BAPTIST CHURCH-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:TONYS FAMILY RESTAURANT-WELL HEAD Zone:Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:DELTA KIDS CENTER *CL 2/07-Well Head Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BON GUSTOS-Well Head Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BON GUSTOS-Bathroom Sink Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:BETHEL MARKET-WELLHEAD Zone:Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:TUGS-Well Head Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: DELTA SPORTSMAN-Well Head Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BAY STANDARDS-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:D ANNA YACHT CENTER-Well Head Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:BYRON AIRPORT-Well Head Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: ANGLER S RANCH #3-WELL 02 Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BETHEL HARBOR-WELL Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:COLONIA SANTA MARIA-Well Head Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:DUTCH SLOUGH WATER WORKS-Well Head Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 6 12 18 24 30 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BYRON CORNERS INC-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: FLAMINGO MOBILE MANOR-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:LINDQUIST LANDING MARINA-Well Head Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:ORWOOD RESORT-WELL 3 - PICNIC AREA Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: ORWOOD RESORT-WELL 2 - WEST WELL Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SUNSET HARBOR-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SANDMOUND MUTUAL-3160 STONE ROAD WELL Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SANDMOUND MUTUAL-3810 STONE ROAD WELL Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: NEIGHBORHOOD CHURCH-Well Head Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: MACS OLD HOUSE-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:ANGLERS SUBDIVISION 4-WELL 1 - 1696 Taylor Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:ANGLERS SUBDIVISION 4-WELL 2 - 1398 Taylor Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: ANGLERS SUBDIVISION 4-WELL 3 - 1698 Taylor Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BRIDGEHEAD CAFE-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:BETHEL ISLAND MUTUAL WATER CO-WELL 1 Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:DELTA MUTUAL WATER COMPANY-East Well Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: DELTA MUTUAL WATER COMPANY-West Well Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: SANTIAGO ISLAND VILLAGE-WELL 01 Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:FRANKS MARINA-Well Head Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:FRANKS MARINA-New Well Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: PLEASANTIMES MUTUAL WATER CO-Well 1 - 4282 STONE Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: PLEASANTIMES MUTUAL WATER CO-WELL 2 - 4520 STONE Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:PLEASANTIMES MUTUAL WATER CO-WELL 3 - 4441 WILLOW Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:RIVERVIEW WATER ASSOCIATION-WELL 1 BEACON HARBOR Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: RIVERVIEW WATER ASSOCIATION-WELL 2 END OF WILLOW RD Zone: Unknown Screened Int.Well Depth: 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: DAVIS CAMP *CL 10/08-west well (north) Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:DAVIS CAMP *CL 10/08-east well (south) Zone:Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:BIG OAK MOBILE HOME PARK WATER-Well Head - West well Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BIG OAK MOBILE HOME PARK WATER-Wellhead- East well Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: BYRON INN-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:SANDY POINT MOBILE HOME PARK-Well Head Zone:Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:CAMINO MOBILEHOME-WELL Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: MARINA MOBILE MANOR-Well Head Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID: MARINA MOBILE MANOR-NEW WELL Zone: Unknown Screened Int.Well Depth: 0 0.2 0.4 0.6 0.8 1 1950 1960 1970 1980 1990 2000 2010 2020NO3-N Concentration (mg/L) WellID:WILLOWEST MARINA WS-WELLHEAD Zone:Unknown Screened Int.Well Depth: {R_WQ_NO3plots} Non-Detects are plotted as 0 Arsenic Graphs 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: BG-1 Zone: Shallow Screened Int.40-55Well Depth:55 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: BG-2 Zone: Shallow Screened Int.22.5-37.5Well Depth:37.5 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:BG-3 Zone:Shallow Screened Int.20-35Well Depth:35 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:SL186102968-7EW-4 Zone:Shallow Screened Int.Well Depth: {R_WQ_ASplots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: SL186102968-7MW-1 Zone: Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: SL186102968-7MW-11 Zone: Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:SL186102968-7MW-12 Zone:Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:SL186102968-7MW-13 Zone:Shallow Screened Int.Well Depth: {R_WQ_ASplots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: SL186102968-7MW-14 Zone: Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: SL186102968-7MW-6 Zone: Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:SL186102968-7MW-8 Zone:Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:SL186102968-7MW-9 Zone:Shallow Screened Int.Well Depth: {R_WQ_ASplots} Non-Detects are plotted as 0 0 6 12 18 24 30 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: SL205032990-W-05 Zone: Shallow Screened Int.Well Depth: 0 16 32 48 64 80 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: T0601300807-IP-1 Zone: Shallow Screened Int.Well Depth: 0 8 16 24 32 40 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:T0601300807-IP-2 Zone:Shallow Screened Int.Well Depth: 0 10 20 30 40 50 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:T0601300807-OW-1 Zone:Shallow Screened Int.Well Depth: {R_WQ_ASplots} Non-Detects are plotted as 0 0 10 20 30 40 50 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: T0601300807-OW-2 Zone: Shallow Screened Int.Well Depth: 0 8 16 24 32 40 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: T0601300807-S-11 Zone: Shallow Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:CITY OF BRENTWOOD-Well 06 Zone:Deep Screened Int.250-300Well Depth:305 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:CITY OF BRENTWOOD-Well 07 Zone:Deep Screened Int.265-295Well Depth:300 {R_WQ_ASplots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: CITY OF BRENTWOOD-Well 08 Zone: Deep Screened Int.225-315Well Depth:325 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: CITY OF BRENTWOOD-Well 11 Zone: Deep Screened Int.255-365Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:CITY OF BRENTWOOD-Well 12 Zone:Deep Screened Int.350-380, 430-450Well Depth:610 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:CITY OF BRENTWOOD-Well 13 Zone:Deep Screened Int.350-380, 430-480Well Depth:510 {R_WQ_ASplots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: CITY OF BRENTWOOD-Well 14 Zone: Deep Screened Int.285-315Well Depth:340 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: CITY OF BRENTWOOD-Well 09 Zone: Deep Screened Int.210-230Well Depth:230 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:CITY OF BRENTWOOD-Well 15 Zone:Deep Screened Int.239-259,289-324Well Depth:345 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:DIABLO WATER DISTRICT-Glen Park Well Zone:Deep Screened Int.230-245, 260-300Well Depth:315 {R_WQ_ASplots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: TOWN OF DISCOVERY BAY-WELL 02 Zone: Deep Screened Int.245-335Well Depth:348 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: TOWN OF DISCOVERY BAY-WELL 05A Zone: Deep Screened Int.251-281, 307-347Well Depth:357 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:TOWN OF DISCOVERY BAY-WELL 04A Zone:Deep Screened Int.307-347Well Depth:357 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:TOWN OF DISCOVERY BAY-WELL 01B Zone:Deep Screened Int.271-289, 308-340Well Depth:350 {R_WQ_ASplots} Non-Detects are plotted as 0 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: KNIGHTSEN ELEMENTARY SCHOOL-WELL 3 Zone: Deep Screened Int.395-415Well Depth:415 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: CITY OF BRENTWOOD-Well 10A Zone: Composite Screened Int.52-72, 135-182Well Depth:210 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:DIABLO WATER DISTRICT-WELL 01 - STANDBY Zone:Composite Screened Int.100-170Well Depth:170 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:KNIGHTSEN ELEMENTARY SCHOOL-SOUTH WELL Zone:Composite Screened Int.167-191, 210-230Well Depth:230 {R_WQ_ASplots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: LOS VAQUEROS MARINA BLDG-SOURCE Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: LOS VAQUEROS INTERPRETIVE CENTER-SOURCE Zone: Unknown Screened Int.Well Depth: 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:SANDMOUND MUTUAL-3810 STONE ROAD WELL Zone:Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:ANGLERS SUBDIVISION 4-WELL 1 - 1696 Taylor Zone:Unknown Screened Int.Well Depth: {R_WQ_ASplots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: ANGLERS SUBDIVISION 4-WELL 2 - 1398 Taylor Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: ANGLERS SUBDIVISION 4-WELL 3 - 1698 Taylor Zone: Unknown Screened Int.Well Depth: 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:DELTA MUTUAL WATER COMPANY-East Well Zone:Unknown Screened Int.Well Depth: 0 4 8 12 16 20 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:DELTA MUTUAL WATER COMPANY-West Well Zone:Unknown Screened Int.Well Depth: {R_WQ_ASplots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: SANTIAGO ISLAND VILLAGE-WELL 01 Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: PLEASANTIMES MUTUAL WATER CO-Well 1 - 4282 STONE Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:PLEASANTIMES MUTUAL WATER CO-WELL 2 - 4520 STONE Zone:Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID:PLEASANTIMES MUTUAL WATER CO-WELL 3 - 4441 WILLOW Zone:Unknown Screened Int.Well Depth: {R_WQ_ASplots} Non-Detects are plotted as 0 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: RIVERVIEW WATER ASSOCIATION-WELL 1 BEACON HARBOR Zone: Unknown Screened Int.Well Depth: 0 2 4 6 8 10 1950 1960 1970 1980 1990 2000 2010 2020Arsenic Concentration (µg/L) WellID: RIVERVIEW WATER ASSOCIATION-WELL 2 END OF WILLOW RD Zone: Unknown Screened Int.Well Depth: {R_WQ_ASplots} Non-Detects are plotted as 0 Groundwater Contamination Sites APPENDIX 3h Contaminated Sites East Conta Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California Global ID Business Name Street Number Street Name City Zip Code Latitude Longitude Case Type Status Status Date Potential Contaminents of Concern Potential Media of Concern SL0601301206 1810 W. 10TH STREET 1810 W. 10TH STREET Antioch 94509 38.013084 -121.829887 Cleanup Program Site Completed - Case Closed 5/6/2009 Arsenic, Lead Soil T0601300762 A & A MARKET (FORMER)407 MAIN ST Oakley 94561 38.0050065 -121.7504086 LUST Cleanup Site Completed - Case Closed 12/2/1997 Gasoline Soil T0601341681 A STREET EXTENSION A STREET EXTENSION Antioch 94531 38.015655 -121.8078304 LUST Cleanup Site Completed - Case Closed 11/5/2014 Waste Oil / Motor / Hydraulic / Lubricating, Gasoline Other Groundwater (uses other than drinking water) T0601300769 AL EAMES FORD 1400 10TH ST W Antioch 94509 38.0116 -121.82395 LUST Cleanup Site Completed - Case Closed 5/27/2005 Waste Oil / Motor / Hydraulic / Lubricating Aquifer used for drinking water supply SLT5SOO33597 ANCHOR GLASS 1400 WEST 4TH STREET Antioch 38.015531 -121.811412 Land Disposal Site Open 1/1/1965 L10001309503 ANCHOR GLASS LANDFILL 1400 4TH Antioch 94509 38.017154 -121.825447 Land Disposal Site Open 1/1/1965 T10000000655 Angelica Textile Service 1409 4th Street W.Antioch 94509 38.01493011 -121.82441 LUST Cleanup Site Completed - Case Closed 9/19/2011 SL185032890 ANTIOCH DELTA COVE PROJECT / Antioch Diversified Development Associates WILBUR AVE Antioch 94509 38.01481176 -121.803139 Cleanup Program Site Open - Inactive 6/2/2009 T0601300759 ANTIOCH HIGH SCHOOL 700 18TH ST W Antioch 94509 38.0050484 -121.8153591 LUST Cleanup Site Completed - Case Closed 8/27/1987 Waste Oil / Motor / Hydraulic / Lubricating Soil T0601300794 ANTIOCH PAVING COMPANY 2540 WILBUR AVE Antioch 94509 38.0116749 -121.771962 LUST Cleanup Site Completed - Case Closed 2/9/2000 Other Solvent or Non-Petroleum Hydrocarbon Soil SLT5S0383079 ANTIOCH YARD PROPERTY JAMES DONOLON BLVD.Antioch 37.9805364 -121.8234444 Cleanup Program Site Completed - Case Closed 8/19/2011 Diesel, Gasoline Under Investigation T0601376629 B.C. STOCKING (FORMER)1700 DISCOVERY BAY BLVD Byron 94514 37.90166667 -121.6026367 LUST Cleanup Site Completed - Case Closed 10/1/2010 Gasoline, Diesel Other Groundwater (uses other than drinking water) T0601300802 BEACON #3544 (FORMER)7920 BRENTWOOD BLVD Brentwood 94513 37.941358 -121.6960561 LUST Cleanup Site Completed - Case Closed 1/26/2011 Gasoline Aquifer used for drinking water supply T0601325015 BEACON HILLCREST 1801 HILLCREST AVENUE Antioch 94509 38.00377326 -121.7870175 LUST Cleanup Site Completed - Case Closed 2/13/2018 Gasoline Aquifer used for drinking water supply T0601300806 BETHEL IS MUNI IMPROVEMENTS 3085 STONE RD Bethel Island 94511 38.0244212 -121.6550644 LUST Cleanup Site Completed - Case Closed 5/12/2010 Gasoline Soil T0601378938 BETHEL ISLAND GOLF COURSE 3303 GATEWAY ROAD Bethel Island 94511 38.02368333 -121.6357667 LUST Cleanup Site Open - Site Assessment 12/9/2013 Gasoline Other Groundwater (uses other than drinking water) T0601300785 BIG BREAK MARINA 100 BIG BREAK RD Oakley 94561 38.011439 -121.733616 LUST Cleanup Site Completed - Case Closed 11/13/1997 Gasoline Aquifer used for drinking water supply L10006305872 BIOSOLIDS RECLAMATION CAMINO DIABLO ROAD Byron 94514 37.867467 -121.646613 Land Disposal Site Open 1/1/1965 L10001050819 BLACK DIAMOND MINES REG PRESER SO. TERMINUS OF SOMERSVILLE Antioch 94509 Land Disposal Site Open - Verification Monitoring 9/1/2009 T0601300765 BLUE GOOSE PROPERTIES 380 HWY 4 S Brentwood 94513 37.9286867 -121.693474 LUST Cleanup Site Completed - Case Closed 4/14/1997 Gasoline Soil T0601389417 BLUE STAR GAS 1541 CYPRESS ROAD, E Oakley 94561 37.99042 -121.6672933 LUST Cleanup Site Completed - Case Closed 8/30/2011 Gasoline Other Groundwater (uses other than drinking water) T0601300743 BP OIL 3720 LONE TREE WY Antioch 95509 37.983932 -121.806301 LUST Cleanup Site Completed - Case Closed 1/13/1997 Gasoline Aquifer used for drinking water supply T0601300804 BRENTWOOD CARDLOCK 8285 BRENTWOOD BLVD Brentwood 94513 37.93385759 -121.6979599 LUST Cleanup Site Open - Site Assessment 6/14/2016 Gasoline Aquifer used for drinking water supply SL0601334843 BRENTWOOD SHOPPING CENTER 2200 San Jose Avenue Brentwood 94513 37.946104 -121.703137 Cleanup Program Site Completed - Case Closed 6/19/2001 Under Investigation T10000010078 Brentwood Stenzel Lease San Jose Road Brentwood 94513 37.94031 -121.72922 Cleanup Program Site Open - Inactive 1/27/2017 T0601300750 BRENTWOOD SUB STATION 29 SPRUCE ST Brentwood 94513 37.937765 -121.695245 LUST Cleanup Site Completed - Case Closed 10/21/1997 Gasoline Aquifer used for drinking water supply T0601300789 BRIDGEHEAD INC 5540 BRIDGEHEAD RD Oakley 94561 38.005539 -121.750306 LUST Cleanup Site Completed - Case Closed 6/20/2003 Gasoline Aquifer used for drinking water supply T0601300791 BYRON BETHANY IRR. DISTRICT 7995 BRUNS RD Byron 94514 37.8393044 -121.5992445 LUST Cleanup Site Completed - Case Closed 9/13/1989 Gasoline Soil T0601330032 BYRON CORNER'S 15031 BYRON HIGHWAY Byron 94514 37.86677 -121.63661 LUST Cleanup Site Completed - Case Closed 10/9/2008 Gasoline, Diesel Soil T0601300799 BYRON GARAGE 14711 BYRON HWY Byron 95514 37.871616 -121.641099 LUST Cleanup Site Completed - Case Closed 4/24/1996 Diesel Soil T0601300763 CARL CROSS STATE FARM 415 G ST Antioch 94509 38.014978 -121.813548 LUST Cleanup Site Completed - Case Closed 12/2/1997 Gasoline Soil T0601300778 CHEVRON #9-1757 2100 L ST Antioch 94509 38.00336 -121.820733 LUST Cleanup Site Completed - Case Closed 12/5/1994 Gasoline Aquifer used for drinking water supply T0601300773 CHEVRON #9-3801 5433 NEROLY RD Antioch 94509 38.00459777 -121.7511708 LUST Cleanup Site Completed - Case Closed 5/29/2002 Gasoline Aquifer used for drinking water supply T0601300782 CHEVRON #9-4585 2413 A ST Antioch 94509 38.0000886 -121.8058588 LUST Cleanup Site Completed - Case Closed 8/29/2017 Gasoline Aquifer used for drinking water supply 1 of 6 Geotracker, October 2019 Contaminated Sites East Conta Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California Global ID Business Name Street Number Street Name City Zip Code Latitude Longitude Case Type Status Status Date Potential Contaminents of Concern Potential Media of Concern T10000003117 Chevron Marsh Creek Road-UPRR Crossing Marsh Creek Road Brentwood 94513 37.89636112 -121.6642284 Cleanup Program Site Open - Site Assessment 7/6/2011 Total Petroleum Hydrocarbons (TPH)Soil T10000000197 Chevron TAOC A Street 2205 A Street Antioch 94509 38.001146 -121.804771 Cleanup Program Site Open - Site Assessment 8/13/2008 Crude Oil Other Groundwater (uses other than drinking water), Soil T10000000198 Chevron TAOC New Love Pump Sta.Willow Ave Antioch 94509 37.99322032 -121.7630625 Cleanup Program Site Completed - Case Closed 11/16/2010 Crude Oil Soil, Soil Vapor, Surface water SL0601319412 CHEVRON TEXACO, BRUNS BYRON RD (MILEPOST 225.6)Byron 37.8312 -121.6057 Cleanup Program Site Completed - Case Closed 11/19/2003 Heating Oil / Fuel Oil Other Groundwater (uses other than drinking water), Soil SL0601380416 CHEVRON, CENTRAL BLVD CENTRAL BOULEVARD Brentwood 94513 37.935668 -121.701307 Cleanup Program Site Completed - Case Closed 2/22/2012 * Petroleum - Other Aquifer used for drinking water supply, Soil, Soil Vapor, Under Investigation SL0601370344 CHEVRON, HICKSON KERLEY 3951 OAKLEY ROAD Antioch 94509 37.9968 -121.7711 Cleanup Program Site Completed - Case Closed 8/8/2012 Heating Oil / Fuel Oil Other Groundwater (uses other than drinking water), Soil SL0601316394 CHEVRON, HOLEY-BYRON ROAD HOLEY ROAD Byron 94514 37.831039 -121.614936 Cleanup Program Site Completed - Case Closed 9/13/2012 Other Solvent or Non-Petroleum Hydrocarbon Under Investigation SL0601377128 CHEVRON, MINNESOTA AVE CAMBRIAN PLACE Brentwood 94513 37.9513 -121.7144 Cleanup Program Site Completed - Case Closed 12/17/2009 Gasoline Other Groundwater (uses other than drinking water), Soil SL0601311093 CHEVRON, TAOC BYRON HOT SPRINGS 5301 BYRON HOT SPRINGS RD Byron 94514 37.8482 -121.6223 Cleanup Program Site Completed - Case Closed 6/18/2014 Crude Oil Other Groundwater (uses other than drinking water), Soil SL0601351425 CHEVRON, WALNUT BLVD WALNUT BOULEVARD Brentwood 94513 37.931234 -121.696329 Cleanup Program Site Completed - Case Closed 6/18/2015 Other Solvent or Non-Petroleum Hydrocarbon, Crude Oil Under Investigation T0601389036 CITY OF ANTIOCH CORP YARD 1201 WEST 4TH STREET Antioch 94531 38.0144 -121.82228 LUST Cleanup Site Completed - Case Closed 11/5/2014 Gasoline Aquifer used for drinking water supply T0601300798 CONTRA COSTA COUNTY FAIR 1201 10TH ST W Antioch 95509 38.0113532 -121.8210234 LUST Cleanup Site Completed - Case Closed 8/12/1996 Gasoline Aquifer used for drinking water supply SLT5S1103150 Cooks Battery Reclamation Site 139 HILL AVENUE Oakley 37.97429 -121.688641 Cleanup Program Site Completed - Case Closed 6/14/2006 Lead Under Investigation T10000008764 Custom Cleaners 2575 main street Oakley 37.99771 -121.73034 Cleanup Program Site Completed - Case Closed 4/21/2016 Tetrachloroethylene (PCE)Soil Vapor SL0601350932 CYPRESS SQUARE SHOPPING CENTER 2025 MAIN STREET Oakley 38.00353497 -121.733923 Cleanup Program Site Completed - Case Closed 8/30/2001 Dichloroethane (DCA), Dichloroethene (DCE) Other Groundwater (uses other than drinking water) T0601300795 DELTA DODGE 1725 10TH ST W Antioch 94509 38.0111683 -121.8247697 LUST Cleanup Site Completed - Case Closed 7/19/2000 Other Solvent or Non-Petroleum Hydrocarbon Aquifer used for drinking water supply T0601300746 DIAMOND MECHANICAL CO.1705 SOMERSVILLE RD Antioch 94509 38.0093313 -121.8314626 LUST Cleanup Site Completed - Case Closed 5/17/2000 Gasoline Soil T0601300751 DISCOUNT LIQUOR STORE 39 ROSSI AVE Antioch 94509 38.000013 -121.807744 LUST Cleanup Site Completed - Case Closed 2/20/2001 Gasoline Aquifer used for drinking water supply T0601300811 DISCOVERY BAY YACHT HARBOR 5901 MARINA RD Discovery Bay 94524 37.9046377 -121.5902552 LUST Cleanup Site Completed - Case Closed 12/4/2008 Gasoline Aquifer used for drinking water supply SLT5S1283168 DOW CHEMICAL CO.- MARSH CREEK DEHYDRATION STATION MARSH CREEK Brentwood 37.94792973 -121.69318 Cleanup Program Site Completed - Case Closed 3/5/2009 Benzene Soil, Under Investigation T0601300745 DU PONT ANTIOCH WORKS 6000 BRIDGEHEAD RD Antioch 94509 38.0121453 -121.7508293 Cleanup Program Site Open - Remediation 5/1/2001 Gasoline Aquifer used for drinking water supply SL0601340233 DUPONT CHEMICAL CO., ANTIOCH WORKS (E.I. DUPONT)6000 BRIDGEHEAD ROAD Oakley 38.01225481 -121.7505684 Cleanup Program Site Open - Remediation 12/17/2004 * Chlorinated Solvents - PCE, * Chlorinated Solvents - TCE, * Other Spill, * Semi-Volatile Organic Compounds, * Volatile Organic Compounds (VOC) Other Groundwater (uses other than drinking water), Surface water L10003120655 EAST OF ANTIOCH LANDFILL SOUTH SIDE MARKLEY CREEK Antioch Land Disposal Site Open 1/1/1965 T0601300775 EBMUD - BIXLER 50 BIXLER ST Brentwood 94513 37.93942542 -121.6234159 LUST Cleanup Site Completed - Case Closed 4/10/2018 Gasoline Aquifer used for drinking water supply T0601300797 EXXON #7-3982 2101 SOMERSVILLE RD Antioch 94509 38.001685 -121.839191 LUST Cleanup Site Completed - Case Closed 8/12/1996 Gasoline Soil T0601300808 EXXON SS #7-5138 Case #1 2700 HILLCREST AVE Antioch 94509 37.994418 -121.785059 LUST Cleanup Site Completed - Case Closed 2/8/2001 Gasoline Aquifer used for drinking water supply T0601300783 E-Z SERVE #100972 741 2ND ST Brentwood 94513 37.93389143 -121.6946265 LUST Cleanup Site Open - Site Assessment 4/19/2013 Gasoline Aquifer used for drinking water supply T0601343310 FIRST STOP GAS 7935 BRENTWOOD BLVD Brentwood 94513 37.9408115 -121.6965066 LUST Cleanup Site Open - Remediation 11/1/2010 Gasoline, Diesel Other Groundwater (uses other than drinking water) 2 of 6 Geotracker, October 2019 Contaminated Sites East Conta Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California Global ID Business Name Street Number Street Name City Zip Code Latitude Longitude Case Type Status Status Date Potential Contaminents of Concern Potential Media of Concern SL185922952 FKP INC (FORMERLY HICKSON - KERLEY)3951 OAKLEY RD Antioch 37.99616268 -121.7676544 Cleanup Program Site Open - Site Assessment 5/1/2016 * Fertilizers, * Metals/Heavy Metals, * Other Spill Other Groundwater (uses other than drinking water) T0601300753 FOOD & LIQUOR #179 1502 DISCOVERY BAY BLVD Byron 94514 37.9066246 -121.6033624 LUST Cleanup Site Completed - Case Closed 9/13/2000 Gasoline Aquifer used for drinking water supply T0601300767 FOOD & LIQUOR #86 HWY 4 & CYPRESS Oakley 94561 37.99041708 -121.6965197 LUST Cleanup Site Completed - Case Closed 8/14/1995 Gasoline Soil T10000008457 Former Delta Cleaners 219 Oak Street Brentwood 94513 37.93321 -121.69436 Cleanup Program Site Open - Site Assessment 2/8/2016 Tetrachloroethylene (PCE)Under Investigation T0601300761 FORMER DICK KANE MOTORS 3100 DELTA FAIR BLVD Antioch 94509 38.0013505 -121.8380617 LUST Cleanup Site Completed - Case Closed 6/11/1997 Gasoline Aquifer used for drinking water supply T0601300756 FORMER EXXON 7-3615 2610 CONTRA LOMA BLVD Antioch 94509 37.9989086 -121.8216102 LUST Cleanup Site Completed - Case Closed 5/29/2012 Gasoline Aquifer used for drinking water supply T0601300800 FORMER SERVICE STATION 1809 A ST Antioch 95509 38.0044295 -121.8058958 LUST Cleanup Site Open - Site Assessment 7/27/2017 Other Solvent or Non-Petroleum Hydrocarbon, Benzene, Ethylbenzene, Gasoline, MTBE / TBA / Other Fuel Oxygenates, Total Petroleum Hydrocarbons (TPH), Xylene Well used for drinking water supply T10000009947 Former Somersville ARCO Service Station 2698 Somersville Road Antioch 37.99903 -121.84303 Non-Case Information Informational Item 12/8/2016 Benzene, Gasoline T0601372054 FRIENDLY HARBORS, LLC 7000 HOLLAND TRACT ROAD Brentwood 94513 37.97360667 -121.58215 LUST Cleanup Site Completed - Case Closed 8/31/2009 Gasoline, Diesel Other Groundwater (uses other than drinking water) SLT5S1443184 Fulton Shipyard 307 FULTON SHIPYARD ROAD Antioch 38.01675588 -121.8022227 Cleanup Program Site Open - Site Assessment 1/1/2013 Lead, Other Metal, Other Petroleum, Total Petroleum Hydrocarbons (TPH)Soil T0601300809 GAS FOR LESS 924 10TH ST W Antioch 95509 38.01140736 -121.8181786 LUST Cleanup Site Open - Site Assessment 7/1/2015 Gasoline Aquifer used for drinking water supply T0601300749 GAYLORD (FORMER FIBERBOARD)1700 4TH ST Antioch 94509 38.0170839 -121.827745 LUST Cleanup Site Completed - Case Closed 8/12/1996 Diesel Aquifer used for drinking water supply SL0601314468 GAYLORD CONTAINER CORPORATION- East Mill 2603 WILBUR AVE Antioch 38.014833 -121.77047 Cleanup Program Site Open - Remediation 10/19/2012 * Perchlorate, * Volatile Organic Compounds (VOC) Aquifer used for drinking water supply, Contaminated Surface / Structure, Other Groundwater (uses other than drinking water), Soil SL0601350099 GWF POWER PLANT - ANTIOCH 1900 WILBUR AVENUE Antioch 38.011724 -121.780983 Cleanup Program Site Completed - Case Closed 6/27/2012 Diesel Other Groundwater (uses other than drinking water) T0601300776 HICKMOTT CANNERY (FORMER)5TH & B ST Antioch 94509 38.015858 -121.806506 LUST Cleanup Site Completed - Case Closed 1/28/2016 Gasoline Aquifer used for drinking water supply SL186423613 HICKMOTT CANNERY (FORMER)5th & B ST Antioch 94509 38.015858 -121.805991 Cleanup Program Site Open - Inactive 2/10/2016 Arsenic, Other Metal SL186232981 HICKSON-KERLEY PIPELINE RELEASE 3951 OAKLEY RD Antioch 37.99677143 -121.771152 Cleanup Program Site Completed - Case Closed 3/20/2012 T0601378105 HILLCREST VALERO Case #2 2700 HILLCREST AVE Antioch 94509 37.994418 -121.785129 LUST Cleanup Site Completed - Case Closed 5/5/2005 Diesel Soil SL0601327206 INLAND MARINE (FORMER)1600 W. 10TH STREET,Antioch 38.0124492 -121.8263626 Cleanup Program Site Completed - Case Closed 2/28/2012 Waste Oil / Motor / Hydraulic / Lubricating Soil L10007411167 JERSEY ISLAND ASH DISPOSAL DUTCH SLOUGH Jersey Land Disposal Site Open 1/1/1965 T0601300780 KILPATRICK'S BAKERIES DEPOT 1801 SOMERSVILLE RD Antioch 94509 38.00919318 -121.8314927 LUST Cleanup Site Completed - Case Closed 2/18/2010 Gasoline Aquifer used for drinking water supply T0601300801 KLM TRANSPORTATION 1831 SOMERSVILLE RD Antioch 95509 38.0061938 -121.8344618 LUST Cleanup Site Completed - Case Closed 10/6/1998 Diesel Aquifer used for drinking water supply SL205383009 KMEP BALFOUR 3150 BALFOUR ROAD Brentwood 94513 37.9252618 -121.7231225 Cleanup Program Site Completed - Case Closed 7/19/2012 Gasoline, * Petroleum - Automotive gasolines, * Petroleum - Diesel fuels Aquifer used for drinking water supply T10000002015 KMEP Brentwood Booster n/a Balfour Rd and State Rte 4 Brentwood 94513 37.92564894 -121.7337942 Cleanup Program Site Open - Remediation 2/27/2017 MTBE / TBA / Other Fuel Oxygenates, Total Petroleum Hydrocarbons (TPH) Other Groundwater (uses other than drinking water), Soil T10000003258 KMEP Orwood Block Valve Release Orwood Brentwood 94513 37.93909965 -121.5780866 Cleanup Program Site Completed - Case Closed 3/2/2017 Diesel, MTBE / TBA / Other Fuel Oxygenates, Gasoline Aquifer used for drinking water supply, Soil, Surface water 3 of 6 Geotracker, October 2019 Contaminated Sites East Conta Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California Global ID Business Name Street Number Street Name City Zip Code Latitude Longitude Case Type Status Status Date Potential Contaminents of Concern Potential Media of Concern T0601300754 LARRY CARTER MARINE BETHEL ISLAND RD Bethel Island 94511 38.0244212 -121.6550644 Cleanup Program Site Completed - Case Closed 11/9/2005 Gasoline Aquifer used for drinking water supply T0601300777 LAURITZEN YACHT HARBOR RTE 1 Antioch 94509 38.0074134 -121.7717579 LUST Cleanup Site Completed - Case Closed 12/2/1997 Gasoline Soil T0601391419 LAURITZEN YACHT HARBOR LLC 115 LAURITZEN LANE Oakley 94561 38.019304 -121.749146 LUST Cleanup Site Completed - Case Closed 6/2/2009 Gasoline Aquifer used for drinking water supply T0601300744 LIBERTY UNION HIGH SCHOOL 850 2ND ST Brentwood 94513 37.93665002 -121.6949558 LUST Cleanup Site Open - Remediation 8/25/2004 Gasoline Aquifer used for drinking water supply T0601300786 LLOYD'S HOLIDAY HARBOR RTE 1 Antioch 94509 38.0074134 -121.7717579 LUST Cleanup Site Completed - Case Closed 12/2/1997 Gasoline Soil SLT5S1813220 Los Vaqueros Water Conveyance Pipeline Project STATION 238+97-240+17 SP UNDERCROSSING Byron 37.88063187 -121.6507018 Non-Case Information Informational Item 10/27/2016 Under Investigation SLT5S1843223 Lyon Woodfield Project East from intersection of Brentwood Blvd and Nancy Street Brentwood 37.94413936 -121.6933409 Cleanup Program Site Completed - Case Closed 7/17/2000 Soil T0601393596 MAGGIORE PROPERTY 1200 BALFOUR RD Brentwood 94513 37.925863 -121.723886 LUST Cleanup Site Completed - Case Closed 4/4/2003 Gasoline Aquifer used for drinking water supply T0601341021 MAZZEI AUTOMOBILE DEALERSHIP (FORMER)1530 WEST 10TH STREET Antioch 94565 38.01194 -121.82513 LUST Cleanup Site Completed - Case Closed 1/9/2012 Gasoline, Waste Oil / Motor / Hydraulic / Lubricating Other Groundwater (uses other than drinking water) T0601300810 NEW BRIDGE MARINA 6325 BRIDGEHEAD RD Antioch 94509 38.0168421 -121.7509044 LUST Cleanup Site Completed - Case Closed 8/19/2009 Gasoline Aquifer used for drinking water supply T0601300758 OAKLEY BUILDERS SUPPLY 800 MAIN ST Oakley 94561 38.0052385 -121.7444308 LUST Cleanup Site Completed - Case Closed 12/2/1997 Gasoline Soil T0601359797 OLYMPIAN TEXACO STATION 2310 A STREET Antioch 94509 38.00021339 -121.8061272 LUST Cleanup Site Open - Verification Monitoring 6/13/2014 Gasoline Aquifer used for drinking water supply SL185062892 OXY USA, INC. FORMER WILLIAMSON TANK FARM DEER VALLEY ROAD Brentwood 37.93308863 -121.7007116 Cleanup Program Site Completed - Case Closed 2/20/2003 Aquifer used for drinking water supply SL0601327305 PACIFIC GAS & ELECTRIC 5400 NERLOY Oakley 38.004239 -121.749912 Cleanup Program Site Completed - Case Closed 3/23/2010 * Volatile Organic Compounds (VOC)Aquifer used for drinking water supply T0601300747 PANTELL'S MUSIC BOX 407 G ST Antioch 94509 38.0154171 -121.8135982 LUST Cleanup Site Completed - Case Closed 10/15/2013 Gasoline Aquifer used for drinking water supply T0601300779 PECKHAM PROPERTY 3215 18TH ST E Antioch 94509 38.005953 -121.760986 LUST Cleanup Site Completed - Case Closed 1/27/1997 Gasoline Soil T0601300781 PERCY'S RADIATOR 901 A ST Antioch 94509 38.011985 -121.8057 LUST Cleanup Site Completed - Case Closed 2/13/2013 Diesel Aquifer used for drinking water supply T0601391420 PETROL EXPRESS 1800 10TH ST W Antioch 94509 38.012637 -121.82974 LUST Cleanup Site Completed - Case Closed 11/21/2014 Gasoline Aquifer used for drinking water supply T0601300752 PG&E (FORMER CORP. YARD)BUCHANAN RD Antioch 94509 37.9956467 -121.8065358 LUST Cleanup Site Completed - Case Closed 4/28/2000 Gasoline Aquifer used for drinking water supply SL0601394831 PG&E ANTIOCH NATURAL GAS TERMINAL 5900 BRIDGEHEAD ROAD Oakley 38.00961789 -121.7499652 Cleanup Program Site Open - Eligible for Closure 7/10/2018 Benzene, Diesel, Ethylbenzene, Gasoline, Toluene, Total Petroleum Hydrocarbons (TPH), Xylene Aquifer used for drinking water supply, Soil, Soil Vapor, Well used for drinking water supply T0601300787 PG&E ANTIOCH SERVICE CENTER 2111 HILLCREST AVE Antioch 94509 37.99949383 -121.7865157 LUST Cleanup Site Completed - Case Closed 11/4/1992 Waste Oil / Motor / Hydraulic / Lubricating Soil SL205092993 PG&E Antioch Service Yard Northern Parcel SOMERSVILLE AND BUCHANAN RD Antioch 37.99766936 -121.8435717 Cleanup Program Site Open - Remediation 5/24/2017 Trichloroethylene (TCE), Benzene, Diesel, Ethylbenzene, Gasoline, Naphthalene, Toluene, Total Petroleum Hydrocarbons (TPH), Xylene Other Groundwater (uses other than drinking water) T10000009571 PG&E Antioch Service Yard Southern Parcel SOMERSVILLE AND BUCHANAN RD Antioch 94509 37.9967 -121.84419 Cleanup Program Site Completed - Case Closed 12/1/2016 Benzene, Diesel, Ethylbenzene, Gasoline, Toluene, Total Petroleum Hydrocarbons (TPH), Xylene Other Groundwater (uses other than drinking water) SL186102968 PG&E DUTCH SLOUGH DEHYDRATOR STATION 1126 Fetzer Lane Oakley 94561-6004 37.997942 -121.709278 Cleanup Program Site Open - Site Assessment 7/21/2017 Benzene, Diesel, Ethylbenzene, Gasoline, Toluene, Total Petroleum Hydrocarbons (TPH), Waste Oil / Motor / Hydraulic / Lubricating, Xylene Aquifer used for drinking water supply, Soil 4 of 6 Geotracker, October 2019 Contaminated Sites East Conta Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California Global ID Business Name Street Number Street Name City Zip Code Latitude Longitude Case Type Status Status Date Potential Contaminents of Concern Potential Media of Concern SL0601346154 PG&E OAKLEY RD METERING STATION OAKLEY ROAD Antioch 94509 37.997698 -121.759578 Cleanup Program Site Open - Remediation 11/20/2013 Other Petroleum Aquifer used for drinking water supply SL205032990 Pioneer Americas (former KEMWATER & former IMPERIAL WEST)2151 WILBUR AVE Antioch 38.013806 -121.778516 Cleanup Program Site Open - Remediation 1/1/2002 * * CHLORIDE, * * IRON, * * MAGNESIUM, * * MANGANESE, Nitrate Other Groundwater (uses other than drinking water) T0601359254 PRIVATE RESIDENCE PRIVATE RESIDENCE Brentwood 94513 37.93461333 -121.69216 LUST Cleanup Site Completed - Case Closed 11/9/2009 Diesel Aquifer used for drinking water supply T0601300788 PROSPECTS 820 2ND ST Antioch 94509 38.01702695 -121.8173656 LUST Cleanup Site Completed - Case Closed 9/27/2012 Gasoline Aquifer used for drinking water supply T0601358660 RAIN FOR RENT 5301 LIVE OAK AVENUE Oakley 94561 38.0018 -121.74332 LUST Cleanup Site Completed - Case Closed 4/8/2008 Diesel, Waste Oil / Motor / Hydraulic / Lubricating Other Groundwater (uses other than drinking water) SL0601301938 RAVENSWOOD (DELTA LAKES)POINT OF TIMBER RD Brentwood 37.910976 -121.632103 Cleanup Program Site Completed - Case Closed 3/17/2017 SL0601399070 RESERVOIR 50 UNKNOWN Antioch 37.99288211 -121.8419838 Cleanup Program Site Completed - Case Closed 6/24/2003 Under Investigation T0601300784 ROMI'S FOOD AND LIQUOR 418 18TH ST E Antioch 94509 38.0047625 -121.7978116 LUST Cleanup Site Completed - Case Closed 7/27/2010 Gasoline Aquifer used for drinking water supply T0601300793 RUSTY PORT HOLE/BOYDS HARBOR 3895 WILLOW RD Bethel Island 94511 38.0365746 -121.6258179 LUST Cleanup Site Completed - Case Closed 12/3/1997 Gasoline Soil T0601300755 SAVER'S SS 2323 HWY 4 Brentwood 94513 37.9391544 -121.6937351 LUST Cleanup Site Completed - Case Closed 12/2/1997 Gasoline Soil SL0601397127 SCIORTINO WELL AREA BRENTWOOD BLVD Brentwood 37.94803307 -121.6908472 Cleanup Program Site Completed - Case Closed 6/1/2009 Gasoline, Diesel Soil T0601300760 SCOTTO'S AUTO PAINTING 1311 4TH ST Antioch 94509 38.015118 -121.822693 LUST Cleanup Site Completed - Case Closed 12/7/1987 Diesel Soil T0601300774 SHELL 2838 LONE TREE WY Antioch 94509 37.993946 -121.808214 LUST Cleanup Site Completed - Case Closed 2/9/1990 Waste Oil / Motor / Hydraulic / Lubricating Soil T0601300403 SHELL 2010 SOMERSVILLE RD Antioch 94531 38.002688 -121.839233 LUST Cleanup Site Completed - Case Closed 6/10/1997 Gasoline Other Groundwater (uses other than drinking water) T0601306725 SHELL SERVICE STATION CASE #2 2838 LONE TREE Antioch 94509 37.99391333 -121.8081533 LUST Cleanup Site Completed - Case Closed 11/9/2010 MTBE / TBA / Other Fuel Oxygenates Other Groundwater (uses other than drinking water) T0601300771 SHELL SS CASE #1 1800 A ST Antioch 94509 38.004695 -121.806349 LUST Cleanup Site Completed - Case Closed 1/8/1997 Gasoline Aquifer used for drinking water supply T0601300807 SHELL SS CASE #2 1800 A ST Antioch 94509 38.0048494 -121.8061518 LUST Cleanup Site Open - Assessment & Interim Remedial Action 8/3/2017 Gasoline Aquifer used for drinking water supply T0601300768 SHELL SS (EX-TEXAXO/REGAL)2010 Auto Center Drive Antioch 94509 38.00261155 -121.8392458 LUST Cleanup Site Completed - Case Closed 9/3/2014 Gasoline Aquifer used for drinking water supply T0601300803 SILVERA PROPERTY 900 A ST Antioch 94509 38.01124464 -121.8062997 LUST Cleanup Site Open - Remediation 6/8/2011 Gasoline Aquifer used for drinking water supply SL186343607 SR4 BYPASS AUTHORITY DAVIS PROPERTY STATE RT 4 BYPASS AUTHORITY Brentwood 37.93308863 -121.7007116 Cleanup Program Site Completed - Case Closed 5/1/2002 Other Groundwater (uses other than drinking water) SL186172975 TERMO CO SOUTHWEST END OF SAN JOSE AVE Brentwood 37.93308863 -121.7007116 Cleanup Program Site Completed - Case Closed 12/6/2000 Other Groundwater (uses other than drinking water) T0601300748 TERMO COMPANY SAN JOSE AVE Brentwood 94513 37.9340945 -121.6999951 LUST Cleanup Site Completed - Case Closed 10/31/1986 Gasoline Soil SL185522920 TEXACO WELDON & COMPILLI PROPERTY BYRON RD Byron 37.84881851 -121.6225547 Cleanup Program Site Completed - Case Closed 6/18/2014 T0601300770 TOSCO - FACILITY #5963 2701 CONTRA LOMA BLVD Antioch 94509 37.9979626 -121.8219562 LUST Cleanup Site Completed - Case Closed 1/9/2014 Gasoline Aquifer used for drinking water supply T0601300790 UNOCAL #2998 (FORMER)1029 10TH ST Antioch 94509 38.01099872 -121.8194167 LUST Cleanup Site Completed - Case Closed 11/8/2011 Gasoline Aquifer used for drinking water supply T0601300772 UNOCAL #3946 1601 A ST Antioch 94509 38.0063554 -121.8058529 LUST Cleanup Site Completed - Case Closed 11/21/2014 Gasoline Aquifer used for drinking water supply T0601300676 USA GASOLINE CORPORATION 1915 Auto Center Drive Antioch 94531 38.006091 -121.834142 LUST Cleanup Site Open - Remediation 11/22/2011 Gasoline Other Groundwater (uses other than drinking water) SL0601391758 WALTER HANSEN TRUST 1809 A STREET Antioch 38.004497 -121.805555 Cleanup Program Site Open - Verification Monitoring 7/9/2009 * Chlorinated Hydrocarbons Aquifer used for drinking water supply T0601300766 WILLIAM HARLOW 206 OAK ST Brentwood 94513 37.9329756 -121.693715 LUST Cleanup Site Completed - Case Closed 2/12/2016 Gasoline Aquifer used for drinking water supply T0601300792 WOODS YACHT HARBOR 3307 WELLS RD Bethel Island 94511 38.0077788 -121.630247 LUST Cleanup Site Completed - Case Closed 1/17/2002 Gasoline Aquifer used for drinking water supply 5 of 6 Geotracker, October 2019 Contaminated Sites East Conta Costa Subbasin Groundwater Sustainability Plan Contra Costa County, California Global ID Business Name Street Number Street Name City Zip Code Latitude Longitude Case Type Status Status Date Potential Contaminents of Concern Potential Media of Concern T0601300764 WOODY'S SERVICE 1022 4TH ST W Antioch 94509 38.0155341 -121.8186813 LUST Cleanup Site Completed - Case Closed 8/19/2010 Gasoline Aquifer used for drinking water supply Note: Data dowloaded from Geotracker 10/8/2018 6 of 6 Geotracker, October 2019 ECC Subbasin Oil and Gas Wells and Fields APPENDIX 3i X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 3i-1 Oil and Gas Well Status, Vicinity of ECC Subbasin.mxd Appendix 3i-1Oil and Gas Well Status, Vicinity of ECC Subbasin East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Well Status Active (153) Canceled (21) Idle (163) New (4) Plugged (846) ECC Subbasin Boundary Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities; Well Status- California Department of Conservation, California Geologic Energy Management Division, Accesed 10/4/2021 ´0 10.5 Miles Brentwood BixlerGas (ABD) KnightsenGas (ABD) OakleyGas (ABD) Brentwood,East, Gas Sand MoundSlough Gas(ABD) Oakley,South, Gas Livermore ShermanIsland Gas LindseySlough Gas Rio Vista Gas KirbyHill Gas HonkerGas(ABD) Tracy, West,Gas (ABD) RiverBreak Gas RiverIsland Gas Van SickleIsland Gas DutchSloughGas McDonaldIsland Gas X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 3i-2 Oil and Gas Fields, Vicinity of ECC Subbasin.mxd Appendix 3i-2Oil and Gas Fields, Vicinity of ECC Subbasin East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Field Boundary ECC Subbasin Boundary Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities; Field Boundaries- California Department of Conservation, California Geologic Energy Management Division, Accesed 10/4/2021´0 10.5 Miles Individual Surface Water Diversions: Point of Delivery Totals by Tract/Model Subregion and by Calendar Year APPENDIX 4a Appendix 1 Reported Individual Surface Water Diversions: Point of Delivery Totals by Tract/Model Subregion and by Calendar Year (AF, source eWRIMS), East Contra Costa Subbasin Subregion Name Antioch Big Break Oakley Jersey Island Bradford Island Webb Tract Franks Tract Bethel Island Holland Tract and Quimby Island (769 ac) Knightsen (Veale Tract (1362) & Bixler (584)) Palm/ Orwood Byron Tract (RD 800) (ac incl some TODB) Clifton Court Forebay Coney Island South Clifton Court Forebay Brent- wood ECCID Discovery Bay BBID North Year/Sub- region Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 2008 0 0 0 0 0 14,700 0 0 10,500 1,850 3,088 59,709 0 0 0 0 0 0 14 89,861 2009 0 0 0 12,862 0 14,700 0 0 10,500 1,550 38,350 61,774 0 0 2,908 0 0 0 12 142,655 2010 0 22 0 12,862 0 14,700 0 0 13,715 10,166 56,542 61,555 0 3,252 2,908 0 0 1,912 15 177,649 2011 0 18 0 12,862 0 14,700 0 0 13,715 11,741 57,963 59,963 0 3,324 2,908 0 0 1,885 12 179,091 2012 0 30 32 12,862 1 14,700 0 0 14,221 9,173 54,734 62,145 0 3,660 2,905 0 0 1,969 12 176,444 2013 0 0 0 25,531 0 14,700 0 2,273 20,400 10,248 55,869 54,214 0 4,722 5,816 0 0 2,084 18 195,874 2014 0 0 0 11,559 0 0 0 4,258 11,811 7,920 41,225 52,630 0 4,769 4,405 0 0 1,785 18 140,380 2015 0 0 0 11,197 0 1,821 0 2,278 11,211 6,263 37,307 44,702 0 3,687 2,647 0 0 1,605 0 122,719 2016 0 0 0 10,366 3 15,043 0 6,136 21,492 5,894 57,027 31,869 0 4,065 2,174 0 0 1,440 18 155,526 2017 0 0 0 13,074 3 15,624 0 5,192 17,631 5,991 40,982 37,824 0 5,150 3,285 0 0 1,153 2 145,912 2018 0 0 0 13,381 3 1,812 0 3,823 15,720 7,037 41,034 25,954 0 2,283 1,780 0 0 1,357 2 114,184 2019 0 0 0 12,422 3 15,658 0 2,174 23,708 6,563 37,254 30,309 0 4,345 3,409 0 0 1,329 11 137,186 Total Note: There may be errors to these data due to a reporting units problem (gallons vs acre-feet) or duplicate reporting (Michael George, Delta Watermaster, Delta Protection Commission meeting September 17, 2020). Model Documentation APPENDIX 5a East Contra Costa Subbasin Groundwater Sustainability Plan (GSP) East Contra Costa Groundwater- Surface Water Simulation Model (ECCSim) Report September 2021 Prepared by Luhdorff & Scalmanini, Consulting Engineers East Contra Costa Subbasin Groundwater Sustainability Plan East Contra Costa Groundwater- Surface Water Simulation Model (ECCSim) Report September 2021 Prepared For ECC Working Group Prepared By Luhdorff & Scalmanini, Consulting Engineers EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE i TABLE OF CONTENTS INTRODUCTION ........................................................................................................................... 7 Background ...................................................................................................................................... 7 Objectives and Approach ................................................................................................................. 7 Report Organization ......................................................................................................................... 8 MODEL CODE AND PLATFORM ..................................................................................................... 8 Integrated Water Flow Model ......................................................................................................... 8 IWFM Demand Calculator ................................................................................................. 8 C2VSim-Fine Grid ............................................................................................................................. 8 GROUNDWATER FLOW MODEL DEVELOPMENT ............................................................................ 9 ECCSim – Historical Model ............................................................................................................... 9 Model Grid ........................................................................................................................ 9 Nodes and Elements ……………………………………………………………………………………………9 Subregions …………………………………………………………………………………………………………10 Surface Water Bodies…………………………………………………………………………………………11 Model Layers……………………………………………………………………………………………………..11 Land Surface System ....................................................................................................... 11 Precipitation..…………………………………………………………………………………………………….12 Evapotranspiration..…………………………………………………………………………………………..12 Land Use ..………………………………………………………………………………………………………….12 Surface Water System ..................................................................................................... 12 Stream Package .………………………………………………………………………………………………..12 General Head Surface Water Features ……………………………………………………………….13 Surface Water Diversions and Deliveries ……………………………………………………………13 Groundwater System ...................................................................................................... 13 Aquifer Parameters ……………………………………………………………………………………………13 Model Boundary Conditions ………………………………………………………………………………14 Groundwater Pumping ………………………………………………………………………………………14 Tile Drains ………………………………………………………………………………………………………….14 Small Watersheds ............................................................................................................ 15 Initial Conditions ............................................................................................................. 15 Model Calibration .......................................................................................................................... 15 ECCSim – Projected Model ............................................................................................................ 16 EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE ii Projected Hydrology ........................................................................................................ 16 Projected Land Use Changes ........................................................................................... 17 Projected Future Scenarios ............................................................................................. 18 Land Surface System ....................................................................................................... 19 Precipitation ………………………………………………………………………………………………………19 Evapotranspiration …………………………………………………………………………………………….19 Land Use ……………………………………………………………………………………………………………19 Surface Water System ..................................................................................................... 19 Surface Water Features ……………………………………………………………………………………19 Groundwater System ...................................................................................................... 20 Boundary Conditions………………………………………………………………………………………….20 Groundwater Pumping ………………………………………………………………………………………21 Sustainable Yield Run …………………………………………………………………………………………21 Initial Conditions ............................................................................................................. 21 GROUNDWATER FLOW MODEL RESULTS .................................................................................... 21 Aquifer Parameters ........................................................................................................................ 21 Hydraulic Conductivity .................................................................................................... 21 Storage Coefficients ........................................................................................................ 21 Groundwater Levels ........................................................................................................ 22 Groundwater Pumping .................................................................................................... 23 Water Budget ................................................................................................................................. 25 Historical Period, 1997-2018 ........................................................................................... 25 Projected Scenarios, 2019-2068 ..................................................................................... 25 Sustainable Yield Projected Period, 2019-2068 .............................................................. 26 MODEL UNCERTAINTY AND LIMITATIONS ................................................................................... 26 CONCLUSIONS AND RECOMMENDATIONS .................................................................................. 27 Conclusions .................................................................................................................................... 27 Recommendations ......................................................................................................................... 27 REFERENCES .............................................................................................................................. 28 EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE iii LIST OF TABLES Table 3-1 ECCSim Grid Characteristics Table 3-2 Model Subregions within ECCSim Table 3-3 Summary of Small Watersheds Table 3-4 Model Data Output and Related Simulation Periods Table 3-5 Incremental Projected Sea Level Rise Amounts (2019-2068) Table 3-6 Projected Change in Urban Areas Table 3-7 Summary of Projected Future Scenarios Table 3-8 Development of Projected Future Land Surface Process Components Table 3-9 Development of Projected Future Surface Water Systems Components Table 4-1 Summary of Calibrated Aquifer Parameter Values Table 4-2 Summary of Historical and Projected Groundwater Pumping in ECCSim LIST OF FIGURES Figure 3-1 Model Grid and Node Refinement Figure 3-2 Modified Nodes and Elements in ECCSim Figure 3-3 Subregions in ECCSim Figure 3-4 ECCSim Stream Network Figure 3-5 Elevation of The Top of Layer 1 Figure 3-6 Elevation of The Top of Layer 2 Figure 3-7 Elevation of The Top of Layer 3 Figure 3-8 Elevation of The Top of Layer 4 Figure 3-9 Elevation of the Bottom of Layer 4 Figure 3-10 Thickness of Layer 1 Figure 3-11 Thickness of Layer 2 Figure 3-12 Thickness of Layer 3 Figure 3-13 Thickness of Layer 4 Figure 3-14 Simulated Surface Water Features Figure 3-15 Historical Surface Water Diversion Locations Figure 3-16 Area of Delta Drains Figure 3-17 Small Watersheds in ECCSim Figure 3-18 Historical Initial Groundwater Heads - Layer 1 Figure 3-19 Historical Initial Groundwater Heads - Layer 2 Figure 3-20 Historical Initial Groundwater Heads - Layer 3 Figure 3-21 Historical Initial Groundwater Heads - Layer 4 EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE iv Figure 3-22 Map of Groundwater Level Calibration Wells Figure 4-1 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 1 Figure 4-2 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 2 Figure 4-3 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 3 Figure 4-4 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 4 Figure 4-5 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 1 Figure 4-6 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 2 Figure 4-7 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 3 Figure 4-8 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 4 Figure 4-9 Calibrated Specific Yield (Sy) - Layer 1 Figure 4-10 Calibrated Specific Yield (Sy) - Layer 2 Figure 4-11 Calibrated Specific Yield (Sy) - Layer 3 Figure 4-12 Calibrated Specific Yield (Sy) - Layer 4 Figure 4-13 Calibrated Specific Storage (SS) - Layer 1 Figure 4-14 Calibrated Specific Storage (SS) - Layer 2 Figure 4-15 Calibrated Specific Storage (SS) - Layer 3 Figure 4-16 Calibrated Specific Storage (SS) - Layer 4 Figure 4-17 Histogram of Residual (Simulated minus Observed) Groundwater Elevations for All Observations Figure 4-18 Histogram of Average Residual (Simulated minus Observed) Groundwater Elevation by Well Figure 4-19 Simulated vs. Observed Groundwater Elevations, By Layer Figure 4-20 Simulated vs. Observed Groundwater Elevations, By Layer Figure 4-21 Residual (Simulated minus Observed) vs. Observed Groundwater Elevations, By Layer LIST OF APPENDICES Appendix A Groundwater Elevation Calibration Hydrographs Appendix B Water Budget Results EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE v LIST OF ABBREVIATIONS 3D Three-Dimensional AF Acre-Feet AN Above Normal BMP Best Management Practice BN Below Normal C Critical C2VSim California Central Valley Groundwater-Surface Water Simulation Model C2VSim-CG California Central Valley Groundwater-Surface Water Simulation Model – Coarse Grid C2VSim-FG Beta2 California Central Valley Groundwater-Surface Water Simulation Model – Fine Grid CDEC California Data Exchange Center CIMIS California Irrigation Management Information System CVHM Central Valley Hydrologic Model CVP Central Valley Project CWD Chowchilla Water District D Dry DWR California Department of Water Resources ECCSim East Contra Costa Groundwater-Surface Water Simulation Model ET Evapotranspiration ETa Actual ET ETc Crop ET ETo Grass Reference ET ETr Alfalfa Reference ET ETref Reference Crop Evapotranspiration eWRIMS SWRCB Electronic Water Rights Information Management System ft/d Feet Per Day GDE Groundwater Dependent Ecosystem GSA Groundwater Sustainability Agency GSP Groundwater Sustainability Plan GWS Groundwater System HCM Hydrogeologic Conceptual Model IDC Integrated Water Flow Model Demand Calculator IWFM Integrated Water Flow Model Kh Horizontal Hydraulic Conductivity Kv Vertical Hydraulic Conductivity MA Management Area Model Numerical Groundwater Flow Model NOAA NCEI National Oceanic and Atmospheric Administration National Centers for Environmental Information NRCS United States Department of Agriculture Natural Resources Conservation Service PRISM Parameter Elevation Regression on Independent Slopes Model SGMA Sustainable Groundwater Management Act of 2014 EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE vi SS Specific Storage SWRCB State Water Resources Control Board SWS Surface Water System Sy Specific Yield USACE United States Army Corps of Engineers USBR United States Bureau of Reclamation USGS United States Geological Survey W Wet WCR Well Completion Report EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 7 INTRODUCTION This report documents the development and calibration of the East Contra Costa Groundwater-Surface Water Simulation Model (ECCSim), a numerical groundwater flow model developed for the East Contra Costa Subbasin to support preparation of its Groundwater Sustainability Plan (GSP) along with other future potential groundwater management and planning needs. This report includes a summary of the model platform, data sources, model development and calibration, and calibration results. Background To support the preparation of the GSP for the East Contra Costa Subbasin, the Groundwater Sustainability Agencies (GSAs) in the Subbasin elected to pursue development of a numerical groundwater flow model to be able to satisfy GSP regulations requiring use of a numerical groundwater model, or equally effective approach, to evaluate projected water budget conditions and potential impacts to groundwater conditions and users from the implementation of the GSP. The development of ECCSim is intended to support groundwater resources management activities associated with GSP development and implementation. ECCSim utilizes data and the hydrogeologic conceptualization that are presented and described in the East Contra Costa Subbasin GSP to improve the understanding of hydrologic processes and their relationship to key sustainability metrics within the Subbasin. ECCSim provides a platform to evaluate potential outcomes and impacts from future management actions, projects, and adaptive management strategies through predictive modeling scenarios. Objectives and Approach Numerical groundwater models are structured tools developed to represent the physical basin setting and simulate groundwater flow processes by integrating a multitude of data (e.g., lithology, groundwater levels, surface water features, groundwater pumping, etc.) that compose the conceptualization of the natural geologic and hydrogeologic environment. ECCSim was developed in a manner consistent with the Modeling Best Management Practices (BMP) guidance document prepared by the California Department of Water Resources (DWR) (DWR, 2016). The objective of ECCSim is to simulate hydrologic processes and effectively estimate historical and projected future hydrologic conditions in the Subbasin related to groundwater dependent ecosystems (GDEs) and SGMA sustainability indicators relevant to the Subbasin including: 1. Lowering of Groundwater Levels 2. Reduction of Groundwater Storage 3. Depletion of Interconnected Surface Water 4. Water-Quality Degradation The development of ECCSim involved starting with and evaluating the beta version (released 5/1/2018) of DWR’s fine-grid version of the California Central Valley Groundwater-Surface Water Flow Model (C2VSim-FG Beta2) and eventually carving out a local model domain and conducting local refinements to the model structure (e.g., nodes, elements) and modifying or replacing inputs as needed to sufficiently and accurately simulate local conditions in the Subbasin within the model domain. C2VSim-FG Beta2 utilizes the most current version of the Integrated Water Flow Model (IWFM) code available at the time of the ECCSim development. IWFM and C2VSim-FG Beta2 were selected as the modeling platform due to the versatility in simulating crop-water demands in the predominantly agricultural setting of the subbasins, groundwater surface-water interaction, the existing hydrologic inputs existing in the model for the time period through the end of water year 2015, and the ability to customize the existing C2VSim-FG Beta2 model to be more representative of local conditions in the area of the East Contra Costa Subbasin. ECCSim was refined from C2VSim-FG Beta2 and calibrated to a diverse set of available historical data using industry standard techniques. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 8 Report Organization This report is organized into the following sections: • Section 2: Model Code and Platform • Section 3: Groundwater Flow Model Development • Section 4: Groundwater Flow Model Results • Section 5: Model Uncertainty and Limitations • Section 6: Conclusions and Recommendations • Section 7: References MODEL CODE AND PLATFORM The modeling code and platform utilized for ECCSim are described below. As required by GSP regulations, the selected model code is in the public domain. The decision to select the model codes for the ECCSim was based on providing the Subbasin with a modeling tool that can be used for GSP development with sufficient representation of local conditions, while utilizing to the extent possible, previous modeling tools available, including regional models. With this objective in mind, the model tools and platforms described below were determined to be most suitable for adaptation for use in GSP analyses. Integrated Water Flow Model IWFM is a quasi three-dimensional finite element modeling software that simulates groundwater, surface water, groundwater-surface water interaction, as well as other components of the hydrologic system (Dogrul et al., 2017). ECCSim is developed using the IWFM Version 2015 (IWFM-2015) code, which couples a three-dimensional finite element groundwater simulation process with one-dimensional land surface, river, lake, unsaturated zone and small-stream watershed processes (Brush et al., 2016). A key feature of IWFM-2015 is its capability to simulate the water demand as a function of different land use and crop types, and compare it to the historical or projected amount of water supply (Dogrul et al., 2017). IWFM uses a model layering structure in which model layers represent aquifer zones that are assigned aquifer properties relating to both horizontal and vertical groundwater movement (e.g., horizontal and vertical hydraulic conductivity) and storage characteristics (e.g., specific yield, specific storage) with the option to associate an aquitard to each layer, although represented aquitards are assigned a more limited set of properties relating primarily to their role in vertical flow (e.g., vertical hydraulic conductivity). The IWFM-2015 source code and additional information and documentation relating to the IWFM-2015 code is available from DWR at the link below: http://baydeltaoffice.water.ca.gov/modeling/hydrology/IWFM/IWFM- 2015/v2015_0_630/index_v2015_0_630.cfm IWFM Demand Calculator IWFM includes a stand-alone Integrated Water Flow Model Demand Calculator (IDC) that calculates water demands. Agricultural water demands are calculated in IDC based on climate, land use, soil properties, and irrigation method whereas urban demands are calculated based on population and per-capita water use. ECCSim utilizes IDC to simulate root zone processes and water demands. The physically based IDC version 2015.0.0036 (DWR, 2015) is developed and maintained by DWR. C2VSim-Fine Grid The C2VSim-FG Beta2 model utilizes the IWFM-2015 code and represents a refinement of the previous C2VSim-Coarse Grid (C2VSim-CG) model. Refinements made in the development of C2VSim-FG Beta2 include a finer horizontal discretization, an updated aquifer layering scheme, updated precipitation data, EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 9 and an extended simulation period through water year 2015 (DWR, 2018). C2VSim-CG had an average element size of approximately 15 square miles and the average element size for C2VSimFG Beta2 is about 0.6 square miles. The C2VSimFG Beta2 version available from DWR at the time of the initiation of modeling efforts to support GSP preparation for East Contra Costa, was not a calibrated model version. DWR published a calibrated version of the fine grid model on Tuesday December 8th 2020. GROUNDWATER FLOW MODEL DEVELOPMENT This section describes the spatial and temporal (time-series) structure of the model and the input data that was utilized for model development. The model development process utilized data and information that was available at the time of model development. ECCSim – Historical Model The ECCSim historical model simulates the period from October 1993 through September 2018 at a monthly time step, with a calibration period of October 1996 through September 2018. Annual model time periods are based on water years defined as October 1 through September 30. The historical calibration model period extends from water years 1997 through 2018. Water years 1994 through 1996 are not included as part of the historical calibration period, but are simulated to allow the model some time to adjust to the specified initial conditions and spin-up prior to the calibration period starting in October 1996. Model Grid Although ECCSim focuses on the East Contra Costa Subbasin, the model domain was extended outside the subbasin to incorporate a buffer zone including areas within the Tracy, Eastern San Joaquin, and Solano Subbasins and the Pittsburg Plain Basin. The extent of the buffer zone was determined based on the geometry of delta islands, surface water features, the anticipated impact of groundwater pumping, and jurisdictional boundaries. The ECCSim domain, shown in Figure 3-1, encompasses a total of 207,714 acres. All C2VSim-FG Beta2 model features (e.g., nodes, elements, streams, layers) within this domain were initially considered for adoption in the development of the ECCSim structure, but subsequent modifications and refinements made within ECCSim to these model components were made and are described in this report. Nodes and Elements The ECCSim grid contains 1,097 nodes and 1,209 elements (Figure 3-1). The X-Y coordinates for node locations are presented in the UTM Zone 10N, NAD83 (meters) projected coordinate system. The number of nodes and elements within the ECCSim domain were altered from C2VSim-FG Beta2, the spacing and alignment of nodes and elements were constructed for ECCSim to more accurately align with the GSA boundaries, delta island geometry, and surface water features. Figure 3-2 shows the difference between C2VSim-FG Beta 2 and modified nodes and elements in ECCSim. Table 3-1 presents ECCSim grid characteristics. Table 3-1. ECCSim Grid Characteristics. Nodes 1,097 Elements 1,209 Average Element Size (acres) 172 Minimum Element Size (acres) 0.005 Maximum Element Size (acres) 1,252 Subregions 34 Aquifer Layers 4 EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 10 Subregions Model elements are grouped into subregions to assist in the summarization of model results and development of water budgets. ECCSim includes 34 subregions (listed in Table 3-2). The East Contra Costa Subbasin is divided into 19 water balance subregions. Subregions were delineated by subbasin, and also by GSA and area within the Subbasin. While subregions are used as the basis for summarizing model results, the model simulates hydrologic processes and conditions at the resolution of elements or nodes. Figure 3-3 shows the delineation of subregions included within ECCSim. Table 3-2. Model Subregions within ECCSim. Subregion Subbasin/Basin GSA Area 1 East Contra Costa City of Antioch GSA Antioch 2 East Contra Costa Diablo Water District GSA Big Break 3 Oakley 4 East Contra Costa County of Contra Costa GSA Jersey Island 5 Bradford Island 6 Webb Tract 7 Franks Tract 8 Bethel Island 9 Holland Tract 10 Knightsen 11 Orwood 12 South Discovery Bay 13 Clifton Court Forebay 14 Coney Island 15 South Clifton Court Forebay 16 East Contra Costa City of Brentwood GSA Brentwood 17 East Contra Costa East Contra Costa Irrigation District GSA ECCID 18 East Contra Costa Discovery Bay Community Services District GSA Town of Discovery Bay 19 East Contra Costa Byron-Bethany Irrigation District GSA – East Contra Costa BBID North (Byron Division) 20 Tracy Byron-Bethany Irrigation District GSA - Tracy BBID South (Bethany Division) 21 BBID Mountain House Division 22 Tracy County of San Joaquin GSA – Tracy Hammer Island 23 Union Island 24 Victoria Island 25 Woodward Island 26 Bacon Island 27 Mandeville Island 28 Eastern San Joaquin Central Delta Water Agency GSA Venice Island EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 11 Subregion Subbasin/Basin GSA Area 29 Bouldin Island 30 Solano Reclamation District No. 317 GSA Andrus Island 31 Solano County of Sacramento GSA - Solano Twitchell Island 32 Sherman Island 33 Kimball Island 34 Pittsburg Plain Not Applicable Pittsburg Surface Water Bodies ECCSim simulates surface water bodies including: Marsh Creek, Old River, Middle River, San Joaquin River, Big Break, Franks Tract, and Clifton Court Forebay. Surface water bodies simulated in C2VSimFG Beta2 only include the San Joaquin River, which was deemed insufficient for purposes of this GSP, so the ECCSim was developed to include these other afore-mentioned surface water bodies. The surface water bodies included in ECCSim are shown in Figure 3-4. Model Layers The C2VSim-FG Beta2 model layering was adapted for ECCSim purposes to better represent the hydrogeological conceptual model (HCM) of the aquifer system through model layering. Within the ECCSim domain, C2VSim-FG Beta2 delineates three aquifer layers; ECCSim was refined to include four aquifer layers corresponding with key hydrogeologic features identified in the Hydrogeologic Conceptual Model (HCM) for the Subbasin. The aquifer system within ECCSim is broken down into the Shallow Aquifer (layers 1 and 2) and the Deep Aquifer (layers 3 and 4). Using the HCM shallow and deep aquifer zones, the shallow zone is divided into two layers using CVHM’s bottom of layer 1. CVHM’s layer 2 is very similar to the HCM’s delineation of the vertical boundary between the shallow and deep aquifer zones. Since according to the HCM, most of the wells in ECC are completed in the shallow zone, the deep aquifer zone is split into two model layers to account for deeper production and/or public supply wells that extend past the base of the shallow aquifer zone. Generally, layer thicknesses increase to the east. A summary of the model layering is stated below: • Top of Layer 1: Land Surface • Bottom of Layer 1: based on CVHM’s bottom of layer 1, 50 feet below ground surface • Bottom of Layer 2: based on our HCM Zone 1 and 2 Boundary • Bottom of Layer 3: based on the bottom of the max depths of Production and Public Wells and to the east of the ECC Subbasin, consistent with C2VSimFG-Beta2 bottom of model layers 2 and 3 • Bottom of Layer 4: based on the base of freshwater from HCM, considering C2VSimFG and CVHM’s base of model Elevations and thicknesses of ECCSim aquifer and aquitard layers are shown in Figures 3-5 through 3-13. Land Surface System The IWFM Land Surface Process, which includes the IDC, calculates a water budget for four land use categories: 1) non-ponded agricultural crops, 2) ponded agricultural crops (i.e., rice), 3) native and riparian vegetation, and 4) urban areas. The Land Surface Process calculates water demand at the surface, allocates water to meet demands, and routes excess water through the root zone (Brush et al., 2016). The development of land surface system input files is explained in this section. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 12 Precipitation Monthly precipitation time series data for water years 1922 through 2015 were extracted from C2VSim- FG Beta2. Precipitation rates were extracted for all elements and small watersheds included within the ECCSim model domain. Precipitation data within both C2VSim-FG Beta2 and ECCSim is based on Parameter Elevation Regression on Independent Slopes Model (PRISM) by the PRISM Climate Group at Oregon State University. Similar water year types and total annual precipitation for water years 2016-2018 were identified in previous years to bring the model’s precipitation data up to date. Evapotranspiration Monthly evapotranspiration (ET) time series data was extracted from C2VSim-FG Beta2 for water years 1922 through 2015. Evapotranspiration rates for each agricultural crop, urban outdoors, native vegetation, and bare soil was developed for each Subbasin in C2VSim-FG and for each small watershed. The same water years were repeated as used above for precipitation, based on water year types and annual precipitation, to fill in the ECCSim’s missing years’ data between water years 2016-2018. Adjustments to a subset of ET values were made in order to better match actual agricultural demand, as needed. Land Use Land use work involves using land use surveys from 1995, 2014, and 2016 (DWR) to calculate the acreage of land use categories. To be consistent with C2VSim-FG land use parameters, a total of 24 land use groups were spatially joined to the ECCSim model elements. Most of the land use type categories are for irrigated agriculture (non-ponded crops including corn, pasture, grain, etc.), and the remaining categories cover ponded crops (like rice), native and riparian vegetation, and urban land use. To support water budget development for each land use group, the DWR Integrated Water Flow Model Demand Calculator (IDC) was employed using ECCSIM-updated land use and spatially joined ET and root zone input data from C2VSimFG. The IDC was used for the development of root zone and land and water use budget components on a monthly basis for use with the other flow components of IWFM. Surface Water System Due to the complexity of the surface water system in the ECCSim model domain, several approaches were employed to simulate the movement of surface water. The ECCSim model advances the representation of surface water bodies compared to C2VSim and C2VSimFG because the latter only simulated the San Joaquin River. ECCSim includes Marsh Creek, Old River, Middle River, San Joaquin River, Big Break, Franks Tract, Clifton Court Forebay, and the Delta into the simulated surface water system. Figure 3-14 shows the simulated surface water features in the ECCSim model. Stream Package The only surface water body that utilizes the stream package in IWFM is Marsh Creek. Marsh Creek is simulated with stream bed parameters estimated from elevation maps, soil properties, and stream characteristics. Rating curves for Marsh creek were developed using stage and gage data. Stream bed parameters, particularly stream bed conductivity and wetted perimeter, were further refined during the calibration process. Stream inflows for Marsh Creek were estimated based on stream gage data from USGS Station 11337600 (Marsh Creek at Brentwood, CA) and California Data Exchange Center’s MDA Station (Marsh Creek at Dainty Ave). EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 13 General Head Surface Water Features Due to the nature of the engineering, controlled flows, and tidal influence of other surface water bodies in the model domain, the Middle River, San Joaquin River, Old River, Clifton Court Forebay, Franks Tract, and the Delta are simulated using general head boundaries. Similar to the simulation of the Delta in CVHM, general head boundaries were used along these surface water features. The elevations used for the general head inputs along these surface water features were based on stage data and interpolated stages between gaging stations. Stations used for analysis and estimation of the time-series stage (general head) values for nodes along rivers in ECCSim included: Venice Island, Three Mile Slough at San Joaquin River, San Joaquin River at Jersey Point (USGS), San Joaquin River at Antioch, Collinsville on Sacramento River, Middle River at Howard Road Bridge, Middle River at Tracy Blvd, Middle River Above Barrier, Middle River at Union Point, Jones Tract, Middle River at Bacon Island Rd, Old River at Quimbly Island Near Bethel Island, Old River at Coney Island, Old River at Clifton Court Intake, Old River at Delta Mendota Canal, Old River Near Tracy, and San Joaquin River at Prisoners Point Near Termino. Surface Water Diversions and Deliveries Surface water diversions and deliveries are simulated in the model as diversions from a stream node with an assigned delivery destination (water balance subregion). Diversion amounts are based on data received from individual GSA entities, as well as the State Water Resources Control Board Electronic Water Rights Information Management System (eWRIMS) database. Losses associated with surface water deliveries are defined as fractions of each surface water diversion within the model domain and remain constant throughout the simulation period. Recoverable losses occur as seepage of water from the delivery system prior to arrival at the delivery destination. Accordingly, the fraction of recoverable loss represents water that recharges from conveyance losses associated with surface water deliveries. Non-recoverable losses occur from evapotranspiration associated with surface water deliveries. The fraction of non-recoverable loss represents water that does not recharge. The remaining percentage of surface water diversions (after subtraction of recoverable and non-recoverable losses) is considered the delivery fraction. The recoverable loss and non-recoverable loss fractions used in the model were determined based on C2VSim-FG values for diversions in the East Contra Costa and Tracy Subbasins. In ECCSim, surface water diversions are assigned to water balance subregions for water delivery. A total of 86 unique entities that have surface water points of diversion data from eWRIMS were compiled for monthly delivery amounts during the model simulation period. The surface water delivery points of diversion were grouped according to water balance subregion, and combined with GSA-reported purchased water, recycled water, and other surface water sources to provide the water supply for each water balance subregion (groundwater pumping provides the remainder of the water demand, both as reported by GSA entity and estimated for private pumpers). Figure 3-15 shows the locations of historical surface water diversions. Groundwater System The IFWM Groundwater Flow Process balances subsurface inflows and outflows and manages groundwater storage within each element and layer (Brush et al., 2016). The development of groundwater system input files is explained in this section. Aquifer Parameters Initial aquifer parameters were adopted from C2VSim-FG Beta2 and compared to both C2VSim-CG, CVHM values, and qualitatively to the HCM descriptions for appropriateness. Aquifer parameters in ECCSim are EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 14 assigned to each node for each model layer, and were developed to represent subsurface hydrogeologic characteristics. Aquifer parameters were calibrated in groups based on depositional environment for regions that needed adjustment. Depositional environments included Alluvial Plain, Delta Islands, Fluvial Plain, and Marginal Delta Dune as described in the GSP Basin Settings section. Model Boundary Conditions ECCSim utilizes a combination of no-flow boundaries and general head boundary conditions along the model domain’s boundary. No-flow boundaries occur along the western border, and general head boundaries occur along the north, east, and southern model boundaries. General head boundary conductance was determined at each boundary node by layer. Conductance was calculated in each layer based on Kh, distance between boundary nodes, aquifer layer thickness, and the distance from the model boundary (set as 1,000-ft). Transient historical water level boundary conditions were developed using interpreted groundwater elevations from C2VSimFG Beta2. Groundwater elevations from C2VSimFG output over time were assigned to the appropriate corresponding ECCSim layer and node on the northern, eastern, and southern sides of the model domain. Similar water years were repeated as was done for the precipitation and ET records to bring the model forward. Groundwater Pumping Pumping within ECCSim is simulated using a combination of individual wells and elemental pumping. Elemental pumping is calculated internally by the IDC to meet both agricultural and domestic/urban demands after available surface water deliveries have been accounted for. The vertical distribution of pumping by layer in ECCSim was modified based on review of well construction information in DWR’s database of Well Completion Reports (WCR) for wells within the model domain. Agricultural and domestic/urban pumping were distributed vertically based on well construction information data in DWR’s WCR database for respective well types. Individual municipal wells for which GSAs provided monthly pumping records for were simulated directly. Tile Drains Tile drains were incorporated in ECCSim where historic drain maps or direct information from GSAs suggest their location. Figure 3-16 shows the area of drains simulated within the model domain. Information from GSAs supported an estimated depth of either 5 or 8 feet below land surface as the depth of the drains. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 15 Small Watersheds A total of 22 small watersheds were included in ECCSim from C2VSim-FG Beta2 (Figure 3-17). Table 3-3 summarizes the contributions of small watersheds to modeled streams. Minor modifications were made to C2VSim-FG Beta2 small watersheds to properly route water to the water balance subregions in ECCSim by making minor edits to the contributing acreage of small watersheds to better align with model elements along the western boundary. Table 3-3. Summary of Small Watersheds. Water Balance Subregion Fed by Small Watersheds Count of Contributing Watersheds Total Contributing Watershed Acreage 34 5 6,732 1 5 6,631 16 3 12,994 17 1 17,599 19 4 15,782 20 3 16,336 21 1 2,791 TOTAL 22 78,865 Initial Conditions Initial conditions for ECCSim were generated from simulated output from C2VSimCG and the C2VSim- FGC2VSim-FG Beta2 regional models for October 1993 in conjunction with mapped groundwater conditions based on observed groundwater levels and contour interpretation. ECCSim initial Conditions for the unsaturated zone and small watersheds were defined from simulated C2VSim-FGC2VSim-FG Beta2 conditions. Initial water level conditions used in the historical ECCSim runs are shown in Figures 3-18 through 3-21. Model Calibration ECCSim was calibrated through a process of trial and error. The calibration procedure focused on adjusting key model parameter values to improve the fit of simulated data to observed data. The key model parameters included in calibration were aquifer properties and conductance terms associated with surface water features. Aquifer parameters adjusted during calibration included Kh, Kv, Ss, and Sy, which were adjusted from original C2VSimFG aquifer parameters based on depositional environment. Conductance terms associated with streambed properties and simulated surface water features using general head conditions were adjusted during the calibration period to help match shallow groundwater levels in certain areas. Drain elevations were also adjusted in some areas where there was uncertainty about the actual drain elevations and the shallow groundwater levels were not matching observed groundwater levels well. Model results were compared to observed groundwater levels. Observations used to constrain aquifer parameter values included over 3,000 groundwater level observations from 32 wells (Figure 3-22). EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 16 ECCSim – Projected Model ECCSim was used to simulate projected future scenarios including under expected changes in urban growth (land use), and anticipated climate change and sea level rise (hydrology). The projected simulation period runs from WY 2019 through 2068 beginning on October 1, 2018 and ending September 30, 2068, at a monthly time step. The development of the projected future scenarios in ECCSim is described in this section. Projected Hydrology Future hydrology model inputs were projected into the future based on adjustments provided by DWR’s Guidance for Climate Change Data Use During Groundwater Sustainability Plan Development document 1. DWR provides climate change adjustment values for climate data, streamflow data, and sea-level rise information. These adjustments are applied to historical hydrology to achieve a future hydrologic period of 50 years that are representative of hydrology potentially occurring in the future. DWR summarizes the various model outputs and respective timelines, which is repeated in Table 3-4. The most recent fifty-year period of common simulation periods is 1954-2003. Therefore, this historic period was selected to perform the adjustments for developing the future scenario hydrology inputs. Table 3-4. Model Data Outputs and Related Simulation Periods. Model Output Data Simulation Period VIC Precipitation, Reference ET, Unimpaired flows 1915-2011 CalSim II Reservoir outflows, river flows, diversions, deliveries 1921-2003 Common Simulation Period for Models at 2030 and at 2070 1921-2003 (82 years of projected hydrology) In terms of sea-level rise, DWR’s Guidance Document mentions that sea-level rise estimates by the National Research Council (NRC) provide two values of expected sea-level rise as median predicted values for the years 2030 and 2070. These two values are 15 and 45 centimeters, respectively, which translates to about 0.5 to 1.4 feet of sea-level rise. In order to be conservative, the ECCSim’s future scenario will apply these values to the general head values associated with the Delta according to the incremental changes estimated between the simulated future time frame of 2019 to 2068 as specified in Table 3-5. 1 https://water.ca.gov/-/media/DWR-Website/Web-Pages/Programs/Groundwater-Management/Sustainable- Groundwater-Management/Best-Management-Practices-and-Guidance-Documents/Files/Climate-Change- Guidance_Final_ay_19.pdf (accessed 12/10/2020) EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 17 Table 3-5. Incremental Projected Sea Level Rise Amounts (2019-2068). Projected Water Year Projected Sea- Level Rise Incremental Adjustment (ft) Projected Water Year Projected Sea- Level Rise Incremental Adjustment (ft) Projected Water Year Projected Sea- Level Rise Incremental Adjustment (ft) 2019 0 2036 0.65 2053 1.075 2020 0.0455 2037 0.675 2054 1.1 2021 0.091 2038 0.7 2055 1.125 2022 0.136 2039 0.725 2056 1.15 2023 0.182 2040 0.75 2057 1.175 2024 0.227 2041 0.775 2058 1.2 2025 0.273 2042 0.8 2059 1.225 2026 0.318 2043 0.825 2060 1.25 2027 0.364 2044 0.85 2061 1.275 2028 0.409 2045 0.875 2062 1.3 2029 0.455 2046 0.9 2063 1.325 2030 0.5 2047 0.925 2064 1.35 2031 0.525 2048 0.95 2065 1.375 2032 0.55 2049 0.975 2066 1.4 2033 0.575 2050 1 2067 1.425 2034 0.6 2051 1.025 2068 1.45 2035 0.625 2052 1.05 Projected Land Use Changes Urban growth is the main change expected to occur in terms of land use for the future fifty-year time period. Urban growth is expected to change in the Contra Costa County area within the model domain. The projected change in urban acres is provided in Table 3-6. Table 3-6. Projected Change in Urban Areas Area 2016 Urban Area Projected 2026 Urban Area ECC Subbasin 22,596 41,630 Entire Model Domain 30,712 52,593 EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 18 Projected Future Scenarios Five projected future scenarios were simulated to compare possible outcomes. These scenarios include: 1) a Projected Land Use Change scenario; 2) a Projected Land Use Change with Increased Pumping (Sustainable Yield Run); 3) a Projected Land Use Change with Climate Change scenario(s); 4) a Projected Land Use Change with Sea Level Change scenario; and 5) a Projected Land Use Change with Climate Change and Sea Level Change scenario. The projected scenarios with climate change incorporate the 2030 mean climate change scenario adjustment for precipitation, ET, stream inflows, and surface water diversion volumes. Future wet and dry climate change scenarios were also evaluated. The projected scenario with sea-level change uses a ramping up of sea level rise from 0.5 feet in 2030 to 1.5 feet in 2070. All other model inputs are held constant across projected future scenarios. The Projected Land Use Change scenario was chosen as the baseline future projected scenario. The Projected Land Use with Climate Change(s), Projected Land Use Change with Sea Level Rise, and Projected Land Use Change with Climate Change and Sea Level Rise model runs were chosen as sensitivity analysis scenarios. The Projected Land Use Change with Increased Pumping scenario is an attempt to determine the sustainable yield for the East Contra Costa Subbasin, to determine what the sustainable yield of the subbasin might be. Table 3-7 summarizes the differences between each projected future scenario. Table 3-7. Summary of Projected Future Scenarios. Scenario Conditions Projected Land Use Change Projected Land Use Change with Increased Pumping (Sustainable Yield Run) Projected Land Use Change with Climate Change Projected Land Use Change with Sea Level Rise Projected Land Use Change with Climate Change and Sea Level Rise Change in Land Use (Urban Growth) x x x x x Climate Change Adjustment x x Sea Level Rise x x Increased Groundwater Pumping (reducing Surface Water Deliveries) x EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 19 Land Surface System The development of land surface system datasets for projected future scenarios is described below. Precipitation The precipitation amount in each future year was assumed to be equal to the amount in the historical period from 1954-2003. For scenarios with climate change adjustments, the historical precipitation amount was adjusted by using the DWR 2070 median tendency, 2070 wet, and 2070 dry climate change scenario monthly multipliers. Additional information about the development of projected precipitation rates is included in Table 3-8. Table 3-8. Development of Projected Future Land Surface Process Components. Water Budget Component Without Climate Change Adjustments With Climate Change Adjustments (2019-2068) (2019-2068) Precipitation 1954-2003 repeat historical data 1954-2003 historical data adjusted by DWR 2030 central tendency, 2070 wet, and 2070 dry monthly change factors Evapotranspiration 1954-2003 repeat historical data, assuming land use adjusted for projected urban area growth from 2019-2068 1954-2003 historical data adjusted by DWR 2030 central tendency, 2070 wet, and 2070 dry monthly change factors, assuming land use adjusted for projected urban area growth from 2019-2068 Evapotranspiration Evapotranspiration rates were also projected into the future based on historical data from 1954-2003 and projected changes in land use (described in Section 3.3.3.3). Additional information about the development of projected ET rates is included in Table 3-8. Land Use Projected Land Use Change Scenarios Except in areas with urban growth, projected land use acreage in future scenarios was based on 2016 land use from DWR Land Use surveys. In areas with urban growth, agricultural acreage decreases over time with urban expansion in the vicinity of existing urban areas. Table 3-6 describes the changes in urban areas for the subbasin and the model domain. Surface Water System The development of surface water system datasets for projected future scenarios is described below. Surface Water Features Stream inflow volumes and other surface water feature inputs were projected into the future based on historical data from the base period as it corresponds to the projected water year based on water year type. For scenarios with climate change, a climate change adjustment was incorporated into the projections. Additional information about the development of projected stream inflows is included in Table 3-9. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 20 Table 3-9. Development of Projected Future Surface Water System Components. Water Budget Component Without Climate Change Adjustments With Climate Change Adjustments With Sea Level Rise Adjustments (2019-2068) (2019-2068) (2019-2068) Surface Water Inflow - Unimpaired Streams (Marsh Creek) 1954-2003 repeat historical data 1954-2003 historical data adjusted by DWR 2030 central tendency monthly change factors; 2070 wet and 2070 dry monthly change factors were also incorporated 1954-2003 repeat historical data Surface Water Delta Features 1954-2003 repeat historical data 1954-2003 repeat historical data Incremental increase in delta heads based on 2030 and 2070 sea level rises (15 and 45 cm) Surface Water General Head Boundaries (Middle River, Old River, San Joaquin River) 1954-2003 repeat historical data 1954-2003 historical data adjusted by DWR 2030 monthly change factors; 2070 wet and 2070 dry monthly change factors were also incorporated 1954-2003 repeat historical data Surface Water General Head Boundaries (Franks Tract & Clifton Court Forebay) 1954-2003 repeat historical data 1954-2003 repeat historical data 1954-2003 repeat historical data Drains* Repeat historical data Repeat historical data Repeat historical data Diversions* 1954-2003 repeat historical data 1954-2003 historical data adjusted by DWR 2030 monthly change factors; 2070 wet and 2070 dry monthly change factors were also incorporated 1954-2003 repeat historical data *Drains and diversions adjust according to urban growth – drains are removed if urban area extends into drain areas, and diversion amounts increase for urban municipal demand and decrease for removal of agricultural lands as a result of urban growth. Groundwater System The development of groundwater system datasets for projected future scenarios is described below. Boundary Conditions Model boundary general head boundary conditions were developed for use in evaluating potential future conditions in the projected future scenarios. This was completed by matching water year types from the base period of 1997-2018 to the fifty-year period of 1954-2003. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 21 Groundwater Pumping The pumping specifications used for the historical simulation period were retained for the duration of all projected simulations (2019-2068), with the exceptions of the following areas: - Urban areas that rely of groundwater increase municipal pumping according to population growth - Removal of agricultural areas that rely on groundwater due to urban growth results in a decrease in agricultural pumping Sustainable Yield Run The future scenario in which ECCSim is used to estimate the sustainable yield attempts to stress the subbasin at levels not previously experienced. Surface water deliveries were reduced by specified percentages. This allows the model to ramp up the amount of groundwater pumping and it is possible to observe the changes in: groundwater storage, groundwater levels, surface water depletion, and subbasin interflow over a fifty-year time frame. Initial Conditions Initial conditions for projected future simulation in ECCSim were generated from the historical simulation in ECCSim. Initial Conditions for the unsaturated zone, root zone, small watersheds, and groundwater levels were defined as the final conditions of the historical simulation in ECCSim. Generally speaking, the future scenarios are a continuation of the historic simulation period. GROUNDWATER FLOW MODEL RESULTS Calibrated parameter values for the historical model simulation as well as water budgets for both the historical and projected future scenarios in ECCSim are presented in this section. Model calibration involves the adjustment of model parameters to achieve a model that simulates the observed hydrologic system as best possible. Model parameters adjusted during calibration include aquifer parameters, and surface water and drain elevations. The final parameters for the calibrated model are presented in this section. Previous discussion of the calibration process and values was also presented in Sections 3.1 and 3.2. Aquifer Parameters Initial aquifer parameter values assigned to each model element were based on C2VSimFG beta2 reported values. These values were further refined and adjusted during the calibration process. Final calibrated values are presented in Table 4-1. Hydraulic Conductivity The calibrated horizontal hydraulic conductivity (Kh) values range from 0.04 feet per day (ft/d) to 850 ft/d (Table 4-1). The final Kh values in the calibrated model area shown by model layer in Figures 4-1 through 4-4. Calibrated vertical hydraulic conductivity (Kv) values range from 0.0002 ft/d to 52.25 ft/d (Table 4-1). The Kv values in the calibrated model are shown by model layer in Figures 4-5 through 4-8. Storage Coefficients Final specific yield (Sy) values used in the calibrated model range from 0.06 to 0.09 (Table 4-1). Final Sy values in the calibrated model by layer are shown in Figures 4-9 through 4-12. Specific storage (Ss) values used in the calibrated model range from 2.25 x 10-7 ft-1 to 6.00 x 10-5 ft-1 (Table 4-1). Final calibrated Ss values by model layer are shown in Figures 4-13 through 4-16. The calibrated Ss term incorporates elastic storage, inelastic storage, and the compressibility of water. The C2VSim-FG Beta2 model available for use in development of the ECCSim model and at the time of this model report, does not currently include the EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 22 capability to simulate land subsidence. With the inclusion of a subsidence component in future versions of IWFM, which will account for the inelastic storage component, the Ss term can be refined in future versions of ECCSim to include only elastic storage. Table 4-1. Summary of Calibrated Aquifer Parameter Values. Aquifer Parameters Horizontal Conductivity (Kh) Specific Storage (Ss) Specific Yield (Sy) Vertical Conductivity (Kv) Units ft/d ft-1 - ft/d Layer 1 Min 1.00 1.29E-05 0.07 0.05 Max 327.38 6.43E-05 0.11 15.00 Average 35.33 1.88E-05 0.08 2.43 Median 25.00 1.50E-05 0.08 2.00 Layer 2 Min 0.04 4.50E-06 0.07 0.00 Max 327.38 6.43E-05 0.11 2.80 Average 31.77 1.38E-05 0.08 0.46 Median 25.00 7.50E-06 0.08 0.39 Layer 3 Min 0.10 4.50E-07 0.06 0.01 Max 650.00 6.43E-05 0.11 7.00 Average 56.61 9.64E-06 0.08 0.62 Median 25.00 6.75E-06 0.07 0.37 Layer 4 Min 5.75 2.25E-07 0.01 0.14 Max 850.00 7.11E-05 0.11 52.25 Average 100.17 9.77E-06 0.08 2.50 Median 14.10 4.73E-06 0.07 0.19 Groundwater Levels Out of 133 wells with observed groundwater levels in the model domain, a subset of 33 wells was selected for model calibration. Wells were selected to provide a broad representation of the model domain based on the spatial distribution, availability of associated well construction information, depth zone of well completion (e.g., layer 1, 2, 3, or 4), and period of record of available water level data. Simulated and observed groundwater elevations were compared over the 1997 through 2018 calibration period. Well hydrographs of simulated and observed groundwater elevations used for model calibration are included in Appendix A. To quantify model fit between the simulated and observed groundwater levels, residual (simulated minus observed) groundwater levels were calculated for each well. To summarize calibration results, a single model layer was selected to compare to observed water levels. In some cases, a well is constructed across multiple model layers, or no construction details were available to determine where the well was screened. In these cases, a single model layer was chosen for each well based on a qualitative review of the hydrograph. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 23 A histogram of residual groundwater elevations for all observations is shown in Figure 4-17. Residual groundwater levels range from -40 feet to 70 feet, with 72 percent of simulated groundwater elevations within 10 feet of observed and almost 84 percent of simulated groundwater elevations within 20 feet of observed. A review of average residual groundwater elevations by well (Figure 4-18) shows that 14 wells, or 42 percent of total, have an average residual groundwater elevation within 10 feet of observed, while 27 wells, or 82 percent of total, have an average residual groundwater elevation within 20 feet of observed. Average residual groundwater elevations by well range from -34 feet to 34 feet. The relation between observed and simulated groundwater elevations is shown by layer in Figure 4-19. Points plotting above 1-to-1 correlation line represent observations where ECCSim is simulating higher than observed groundwater elevations, while points plotting below the 1-to-1 correlation line represent observations where ECCSim is simulating lower than observed groundwater elevations. In general, points are plotting close to the 1-to-1 correlation line, indicating a good model fit. The relationship between residual and observed groundwater elevations is shown by layer in Figure 4-20. This figure shows that the model generally predicts water levels close to observed in the Upper Aquifer, as the majority of points plot near the origin. The model tends to predict higher than observed levels at lower observed groundwater elevations, while the model tends to predict lower than observed levels at higher observed groundwater elevations. The greatest residuals occur in wells in layers 3 and 4. The spatial distribution of residual errors in the simulated levels are presented by well in Figure 4-21. The East Contra Costa Subbasin is generally well calibrated. Groundwater Pumping Over the historical model period, most of the pumping occurs in the two middle layers (Layers 2 and 3) within the East Contra Costa Subbasin. Approximately 92 percent of pumping occurs in Layers 2 and 3. The proportion and distribution of pumping is maintained for the projected future climate scenarios. The sustainable yield future scenario ramps up the groundwater pumping to determine a higher level of pumping that the ECC Subbasin can sustain without resulting in negative effects including storage depletion, surface water depletion, or reversal of subsurface lateral flow with neighboring subbasins. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 24 Table 4-2. Summary of Historical and Projected Groundwater Pumping in ECCSim. East Contra Costa Subbasin (area 107,596 ac) Model Scenario Model Layer Pumping Amount or Proportion Units Historical Period (1997-2018) Layer 1 319 AF/yr Layer 2 11,699 AF/yr Layer 3 30,835 AF/yr Layer 4 3,602 AF/yr Total Avg Pumping 46,455 AF/yr Total ECC Subbasin Avg Pumping 0.4 AF/ac/yr Layer 1 0.7 % Layer 2 25.2 % Layer 3 66.4 % Layer 4 7.8 % Future Land Use Period (2019-2068) Layer 1 205 AF/yr Layer 2 4,122 AF/yr Layer 3 20,757 AF/yr Layer 4 3,883 AF/yr Total Avg Pumping 28,966 AF/yr Total ECC Subbasin Avg Pumping 0.3 AF/ac/yr Layer 1 0.7 % Layer 2 14.2 % Layer 3 71.7 % Layer 4 13.4 % Future Sustainable Yield2 Period (2019-2068) Layer 1 616 AF/yr Layer 2 7,631 AF/yr Layer 3 59,478 AF/yr Layer 4 4,267 AF/yr Total Avg Pumping 71,992 AF/yr Subbasin Avg Pumping 0.7 AF/ac/yr Layer 1 0.9 % Layer 2 10.6 % Layer 3 82.6 % Layer 4 5.9 % 2 The Sustainable Yield run was developed using a reduction of surface water deliveries by 50%, thereby increasing groundwater pumping without deleterious effects. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 25 Water Budget Groundwater budgets were generated for the East Contra Costa Subbasin for each of the model simulations. Water budget results are presented in the following sections. Historical Period, 1997-2018 The water budget during the historical calibration period simulation was calculated for the 1997-2018 water years from October 1, 1997 through September 30, 2018. Change in groundwater storage shows overall stability over the 21-year historical calibration period. Groundwater leaves the subbasin through drains in amounts that average about 74,800 AFY during the base period. Surface water/groundwater interaction accounts for an average recharge of about 17,800 AF per year. Deep percolation accounts for an average recharge of about 90,000 AF per year. Groundwater pumping accounts for an average discharge of about 46,500 AF per year. Net subsurface outflow accounts for an average of about 8,500 AF per year. There is some uncertainty in subsurface outflow estimates because these calculations depend on a variety of factors inside and outside the subbasin. Detailed historical water budget results for East Contra Costa Subbasin are presented in Appendix B, and groundwater elevation hydrographs at select wells are included in Appendix A. Projected Scenarios, 2019-2068 The water budget during the future projected fifty-year period simulation was calculated for the 2019- 2068 water years from October 1, 2018 through September 30, 2068. Projected Land Use Change Change in groundwater storage shows aquifer storage replenishment as a result of the projected land use change resulting in more urban land in the subbasin. Groundwater leaves the subbasin through drains in amounts that average about 71,200 AFY during the base period. Surface water/groundwater interaction accounts for an average recharge of about 20,300 AF per year. Deep percolation accounts for an average recharge of about 85,000 AF per year. Groundwater pumping accounts for an average discharge of about 46,100 AF per year. Net subsurface outflow accounts for an average of about 7,000 AF per year. Detailed projected water budget results for East Contra Costa Subbasin are presented in Appendix B. Projected Land Use Change with Climate Change Change in groundwater storage shows aquifer storage replenishment as a result of the projected land use change resulting in more urban land in the subbasin. Groundwater leaves the subbasin through drains in amounts that average about 84,000 AFY during the base period. Surface water/groundwater interaction accounts for an average recharge of about 13,900 AF per year. Deep percolation accounts for an average recharge of about 97,000 AF per year. Groundwater pumping accounts for an average discharge of about 34,000 AF per year. Net subsurface outflow accounts for an average of about 11,400 AF per year. Detailed projected water budget results for East Contra Costa Subbasin are presented in Appendix B. Projected Land Use Change with Sea Level Rise Change in groundwater storage shows aquifer storage replenishment as a result of the projected land use change resulting in more urban land in the subbasin. Groundwater leaves the subbasin through drains in amounts that average about 86,500 AFY during the base period. Surface water/groundwater interaction accounts for an average recharge of about 13,300 AF per year. Deep percolation accounts for an average recharge of about 95,700 AF per year. Groundwater pumping accounts for an average discharge of about 29,000 AF per year. Net subsurface outflow accounts for an average of about 13,000 AF per year. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 26 Detailed projected water budget results for East Contra Costa Subbasin are presented in Appendix B. Projected Land Use Change with Climate Change and Sea Level Rise Change in groundwater storage shows aquifer storage replenishment as a result of the projected land use change resulting in more urban land in the subbasin. Groundwater leaves the subbasin through drains in amounts that average about 81,100 AFY during the base period. Surface water/groundwater interaction accounts for an average recharge of about 14,600 AF per year. Deep percolation accounts for an average recharge of about 97,100 AF per year. Groundwater pumping accounts for an average discharge of about 34,000 AF per year. Net subsurface outflow accounts for an average of about 11,400 AF per year. Detailed projected water budget results for East Contra Costa Subbasin are presented in Appendix B. Projected Land Use Change with Wet Climate Change Change in groundwater storage shows aquifer storage replenishment as a result of the projected land use change resulting in more urban land in the subbasin. Groundwater leaves the subbasin through drains in amounts that average about 103,000 AFY during the base period. Surface water/groundwater interaction accounts for an average recharge of about 6,900 AF per year. Deep percolation accounts for an average recharge of about 129,500 AF per year. Groundwater pumping accounts for an average discharge of about 32,600 AF per year. Net subsurface outflow accounts for an average of about 14,800 AF per year. Detailed projected water budget results for East Contra Costa Subbasin are presented in Appendix B. Projected Land Use Change with Dry Climate Change Change in groundwater storage shows aquifer storage replenishment as a result of the projected land use change resulting in more urban land in the subbasin. Groundwater leaves the subbasin through drains in amounts that average about 75,800 AFY during the base period. Surface water/groundwater interaction accounts for an average recharge of about 16,100 AF per year. Deep percolation accounts for an average recharge of about 88,300 AF per year. Groundwater pumping accounts for an average discharge of about 36,100 AF per year. Net subsurface outflow accounts for an average of about 10,000 AF per year. Detailed projected water budget results for East Contra Costa Subbasin are presented in Appendix B. Sustainable Yield Projected Period, 2019-2068 The water budget during the sustainable yield projected period simulation was calculated for the 2019-2068 water years from October 1, 2018 through September 30, 2068. Projected Land Use Change with Increased Pumping Change in groundwater storage shows some aquifer storage replenishment despite increasing the groundwater pumping. Groundwater leaves the subbasin through drains in amounts that average about 56,900 AFY during the base period. Surface water/groundwater interaction accounts for an average recharge of about 19,200 AF per year. Deep percolation accounts for an average recharge of about 96,000 AF per year. Groundwater pumping accounts for an average discharge of about 72,000 AF per year. Net subsurface outflow accounts for an average of about 3,700 AF per year. Detailed projected water budget results for East Contra Costa Subbasin are presented in Appendix B. MODEL UNCERTAINTY AND LIMITATIONS Any groundwater flow model is a simplification of the natural environment, and therefore has recognized limitations. For this reason, uncertainty exists in the ability of any numerical model to completely represent groundwater flow. Some of the uncertainty is associated with limitations in available data. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 27 Considerable effort was made to reduce model uncertainty by improving the calibration of aquifer parameters to better match observed groundwater conditions. The finding and conclusions of this study are focused on a Subbasin scale and use of the model for site- specific analysis should be conducted with an understanding that representation of local site-specific conditions may be approximate and should be verified with local site-specific investigations. The flow model was developed in a manner consistent with the level of care and skill normally exercised by professionals practicing under similar conditions in the area. There is no warranty, expressed or implied, that this modeling study has considered or addresses all hydrogeological, hydrological, environmental, geotechnical or other characteristics and properties associated with the subject model domain and the simulated system. CONCLUSIONS AND RECOMMENDATIONS Based on the calibration of ECCSim to historical conditions for the calibration period from water year 1997 to 2018 and accompanying assessment of model sensitivity, the ECCSim groundwater flow model is suitable for use as a tool to support management of water resources within the East Contra Costa Subbasin. Conclusions ECCSim provides a useful tool for evaluating a wide variety of future scenarios and inform the decision- making process to maintain sustainable groundwater management in the East Contra Costa Subbasin. A numerical model can be a convenient and cost-efficient tool for providing insights into groundwater responses to various perturbations including natural variability and change, and also changes associated with management decisions or other humanmade conditions. However, as with any other modeling tool, information obtained from a numerical model also has a level of uncertainty, especially for long-term predictions or forecasts. The level of uncertainty associated with model simulations are likely to increase the more the scenarios extend beyond the range of historical conditions and processes over which the model was calibrated, such as for long-term predictive scenarios or predictive scenarios with extreme alterations to the hydrologic conditions. Recommendations Future and ongoing updates to ECCSim will be valuable for improving the model performance and verifying the accuracy of the model predictions. Using data from the ongoing monitoring efforts and forthcoming GSP monitoring, ECCSim should be updated periodically, including through extending of the model period and associated inputs. Although the frequency of conducting model updates may depend on a variety of factors, including evaluation of the model performance in predicting future conditions, such an update could initially be considered every five years. This frequency of model update should be adequate and cost effective to test and improve ECCSim periodically with new site-specific and monitoring information. Groundwater elevations, groundwater pumping, rainfall, and stream discharge should be collected on an ongoing basis, to the extent possible, at intervals of at least monthly for pumpage, rainfall, and streamflow, and less frequently (semi-annually at least) for groundwater levels. The new groundwater data should be compared with the respective model simulation results so that the flow model can be verified into the future. If the differences between the measured groundwater data and ECCSim’s predicted results are significant, adjustment and modification may be applied to the model input parameters. ECCSim has been calibrated and verified. It adheres closely to site-specific observed data so that model input parameters are reasonable and appropriate especially within the East Contra Costa Subbasin. Additional model revisions may be conducted in areas outside the East Contra Costa Subbasin as that data is obtained from adjacent GSAs. EAST CONTRA COSTA GROUNDWATER-SURFACE WATER SEPTEMBER 2021 SIMULATION MODEL (ECCSIM) REPORT LSCE 28 Further refinement to ECCSim should be made by addressing key data gaps. The calibrated C2VSimFG model should be evaluated to incorporate any relevant aspects of the model into ECCSim, as appropriate and necessary. In particular, a calibrated land subsidence simulation package should be considered for incorporation into ECCSim. This capability is anticipated with the release of the calibrated C2VSimFG model. Updates to aquifer parameters can be made through incorporation of lithologic information or aquifer testing information developed from new monitoring well construction efforts in the future. Through upcoming GSP-related monitoring, additional groundwater level data can be used to refine boundary condition water levels and improve model calibration. Additional improvements to model calibration can be made by the potential linking of additional well construction information to wells with appropriate monitoring periods of record, and refinements to the simulation of surface water distribution systems. Further refinements to ECCSim can be made by extending the historical base period and ongoing updating of model calibration in preparation for 5-year GSP status/update report. REFERENCES Brush, Charles F., Dogrul, Emin C., and Kadir, Tariq N., 2016, DWR Technical Memorandum: Development and Calibration the California Central Valley Groundwater-Surface Water Simulation Model (C2VSim), Version 3.02-CG, Version 1.1, California Department of Water Resources. California Department of Water Resources (DWR), 2015, Integrated Water Flow Model Demand Calculator (IDC), version 2015.0.0036, Retrieved from: https://water.ca.gov/Library/Modeling-and- Analysis/Modeling-Platforms/Integrated-Water-Flow-Model-Demand-Calculator. California Department of Water Resources (DWR), 2016, Best Management Practices for the Sustainable Management of Groundwater: Modeling, BMP 5. California Department of Water Resources (DWR), 2018. Key Updates to the C2VSim - FG Model. Dogrul, Emin C., Kadir, Tariq N., and Brush, Charles F., 2017, DWR Technical Memorandum: Theoretical Documentation for the Integrated Water Flow Model (IWFM-2015), Revision 630, California Department of Water Resources. SGMA Data Viewer (https://data.cnra.ca.gov/showcase/sgma-data-viewer), downloaded 11/29/20 FIGURES 33 34 1 2 3 4 8 7 6 65 32 31 27 9 26 25 24 14 15 20 19 1313 12 18 11 10 1716 22 23 21 30 29 28 H:\ECCC_SWGW_Tracy\FLOW MODEL\GIS\ECCModel_nodesandelements.mxd Figure 3-1Model Grid and Node Refinement East Contra Costa Groundwater-Surface WaterSimulation Model (ECCSim) Explanation East Contra Costa Subbasin DWR Bulletin 118 Groundwater Subbasins Model Nodes Model Elements Water Balance Subregions 0 1 20.5 Miles ´ !(!(!(!(!(!(!(!(!(!(!(!(!(!(!( !( !(!( !( !(!( !( !( !( !( !(!( !( !( !(!(!( !( !( !( !( !( !( !(!( !( !( !( !(!(!( !( !( !( !( !( !(!(!(!( !( !(!( !( !(!(!(!( !( !( !( !( !( !(!(!(!(!(!(!(!(!( !( !(!( !( !(!(!(!( !( !(!( !( !( !( !( !( !( !( !( !(!( !(!(!(!(!( !( !( !( !( !(!( !( !( !( !(!( !( !(!( !( !( !( !( !( !( !( !(!(!( !(!( !(!(!(!(!( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !(!( !( !( !( !( !( !( !( !( !( !(!(!( !( !( !( !( !(!(!(!(!(!(!(!(!( !(!(!( !(!(!(!( !( !(!(!( !( !(!(!(!(!( !( !( !(!( !( !( !( !( !( !( !( !(!( !( !( !(!( !( !( !(!(!(!(!(!(!(!(!(!(!(!( !( !(!(!(!(!(!( !(!(!(!(!(!(!(!(!(!(!( !(!(!(!(!(!(!( !( !( !( !( !( !( !( !( !(!(!( !( !( !( !( !( !(!( !(!(!( !( !(!( !(!(!(!(!(!(!( !( !( !( !(!(!(!(!(!(!(!(!(!(!(!(!(!(!( !(!(!(!(!(!(!(!( !( !(!( !( !( !( !( !( !( !(!(!( !( !(!( !( !( !(!(!(!(!(!( !( !(!( !( !(!(!(!(!(!( !( !( !(!( !(!(!(!(!( !( !(!(!(!( !(!(!(!(!(!( !(!(!( !(!( !(!(!(!(!( !( !( !( !( !( !(!( !(!( !( !( !( !( !( !(!(!( !(!(!( !( !( !( !( !(!(!(!(!(!( !( !( !( !( !( !(!( !(!(!(!(!(!(!(!(!(!(!( !(!( !(!( !(!( !(!(!(!( !( !( !( !(!(!(!( !( !(!(!( !( !(!( !( !(!(!(!( !(!( !( !( !( !( !(!(!(!(!(!(!( !( !( !( !( !(!(!( !(!(!(!(!( !(!( !(!(!(!(!( !(!( !(!( !( !( !( !(!(!(!( !( !(!( !(!( !(!( !(!(!( !( !(!( !( !(!(!( !(!( !( !( !( !( !(!( !( !(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!( !( !( !( !( !( !(!(!(!(!(!(!(!(!(!(!(!( !(!( !(!( !( !( !( !( !( !(!( !(!(!( !(!( !(!(!( !(!(!( !( !( !( !(!( !(!(!(!( !(!( !( !( !( !( !( !(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!( !( !( !( !( !(!( !(!(!(!( !(!(!(!(!(!(!(!(!(!(!( !( !( !( !( !( !( !( !( !( !( !(!(!( !(!(!( !( !( !( !( !( !(!( !(!(!(!(!(!(!(!(!( !( !( !(!( !(!(!(!( !(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!( !(!( !( !(!( !(!(!(!( !(!(!(!( !(!( !( !(!(!(!(!( !( !( !(!( !( !(!(!(!(!(!(!( !(!(!(!( !( !( !( !( !( !(!(!(!(!(!(!( !(!(!(!(!(!(!( !(!(!(!(!( !( !(!(!(!(!(!(!(!(!(!(!(!( !(!(!(!( !( !(!(!( !(!(!(!(!(!(!(!(!( !(!( !(!(!( !(!(!( !(!( !( !(!( !( !(!(!(!( !(!( !( !(!( !( !( !(!(!(!( !(!(!(!(!( !(!( !( !( !( !(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!( !(!( !(!( !(!(!(!(!(!(!( !(!( !(!(!(!(!( !( !(!(!(!(!(!( !( !(!( !(!(!(!( !(!( !(!( !( !( !( !(!( !(!( !(!( !( !(!(!( !(!(!(!(!( !( !(!(!(!(!(!(!(!(!( !(!(!(!(!(!(!(!(!(!(!(!(!(!(!(!( !( !( !(!(!(!(!( !( !( !( !(!(!(!( !(!( !(!(!( !( !( !( !( !( !( !( !( !( !(!( !( !( !(!( !( !(!(!(!( !(!(!( !( !(!( !(!(!(!(!( !(!(!( !(!( !( !( !(!(!(!( !( !(!(!(!( !( !( !( !( !( !( !( !( !( !(!(!( !( !( !( !( !( !( !(!( !( !( !( !( !( !( !(!( !(!( !(!( !( !( !( !( !( !( !( !( !(!( !(!(!(!( !(!( !(!(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !( !( !(!(!(!( !(!(!(!( !( !( !( !( !( !(!(!(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !( !( !( !( !( !( !(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !( !(!( !(!(!( !( !( !( !( !( !( !( !( !( !(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!(!(!(!( !( !(!(!( !( !( !( !( !( !( !(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!(!(!( !(!(!(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!( !( !( !( !( !( !( !(!(!(!( !(!( !( !( !( !(!( !(!( !( !( !( !( !( !( !( !( !( !(!( !( !( !( !( !( !(!( !(!(!( !( !(!( !(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!(!( !(!( !( !( !( !( !( !( !( !( !( !( !(!(!(!(!(!(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!(!(!( !( !( !( !( !( !( !( !( !( !(!(!(!( !(!( !(!( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !( !(!(!(!( !( !( !( !(!( !( !( !( !( !(!( !( !( !( !(!( !( !( !( !( !( !( !( !( !( !( !(!(!( !( !( !( !( !(!( !(!( !( !(!( !(!( !(!( !( !( !( !( !( !( !( !( !(!( !( !(!( !(!( !(!(!( !(!( !( !( !( !( !(!( !!!!!!!!!!!! !!! !!! !!!! ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!! !! !! !!! !! ! ! ! !!! ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!! !!!!!!!!!!!! !!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !! !!! !!!!!!!!!!!!!!!!!!!!!!!!!! X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.2 Modified Nodes and Elements in ECCSim.mxd Figure 3-2Modified Nodes and Elements in ECCSim East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation !ECC Nodes !(C2VSimFG Nodes ECC Subbasin Boundary ECC Elements Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.3 Subregions in ECCSim.mxd Figure 3-3Subregions in ECCSim East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Subbasin Boundary ECC Subregions Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.4 ECCSim Stream Network.mxd Figure 3-4ECCSim Stream Network East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Simulated Stream Model Boundary ECC Subbasin Boundary Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.5 Elevation of The Top of Layer 1.mxd Figure 3-5Elevation of The Top of Layer 1 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Model Boundary ECC Subbasin Boundary Top of Layer 1Elevation (ft msl)High : 725.011 Low : -70.2741 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.6 Elevation of The Top of Layer 2.mxd Figure 3-6Elevation of The Top of Layer 2 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Model Boundary ECC Subbasin Boundary Top of Layer 2Elevation (ft msl)High : 518.836 Low : -64.1652 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.7 Elevation of The Top of Layer 3.mxd Figure 3-7Elevation of The Top of Layer 3 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Model Boundary ECC Subbasin Boundary Top of Layer 3Elevation (ft msl)High : 17.7188 Low : -261.567 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.8 Elevation of The Top of Layer 4.mxd Figure 3-8Elevation of The Top of Layer 4 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Model Boundary ECC Subbasin Boundary Top of Layer 1Elevation (ft msl)High : -70.377 Low : -661.029 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.9 Elevation of Base of Layer 4.mxd Figure 3-9Elevation of The Bottom of Layer 4 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Model Boundary ECC Subbasin BoundaryBase of Layer 4Elevation (ft msl)High : -187.088 Low : -1965.29 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.10 Thickness of Layer 1.mxd Figure 3-10Thickness of Layer 1 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Subbasin Boundary ECC Model Boundary 50 feet Thickness Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.11 Thickness of Layer 2.mxd Figure 3-11Thickness of Layer 2 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Subbasin Boundary ECC Model Boundary Layer 2 Thickness (ft)High : 600.91 Low : 19.3648 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.12 Thickness of Layer 3.mxd Figure 3-12Thickness of Layer 3 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary Layer 3 Thickness (ft)High : 560.123 Low : 9.5582 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.13 Thickness of Layer 4.mxd Figure 3-13Thickness of Layer 4 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary Layer 4 Thickness (ft)High : 1747.78 Low : 4.05683 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ San Joaquin River Old RiverMar s h C r e e k Clifton Court Forebay X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.14 Simulated Surface Water Features.mxd Figure 3-14Simulated Surface Water Features East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Major Stream in ECCC Surface Water Body Model Boundary ECC Subbasin Boundary Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.15 Historical Surface Water Diversion Locations.mxd Figure 3-15Historical Surface Water Diversion Locations East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Diversion Point Model Boundary ECC Subbasin Boundary Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.16 Area of Delta Drains.mxd Figure 3-16Area of Delta Drains East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation Model Boundary ECC Subbasin Boundary Delta Drains Estimated at 5 ft below Land Surface Delta Drains Estimated at 8 ft below Land Surface Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.17 Small Watersheds in ECCSim.mxd Figure 3-17Small Watersheds in ECCSim East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary Watershed Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.18 Historical Initial Groundwater Heads - Layer 1.mxd Figure 3-18Historical Initial Groundwater Heads - Layer 1 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary Layer 1 GroundwaterHead (ft)High : 92.1844 Low : -32.9363 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.19 Historical Initial Groundwater Heads - Layer 2.mxd Figure 3-19Historical Initial Groundwater Heads - Layer 2 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Subbasin Boundary ECC Model Boundary Layer 2 GroundwaterHead (ft)ValueHigh : 87.0549 Low : -32.9363 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.20 Historical Initial Groundwater Heads - Layer 3.mxd Figure 3-20Historical Initial Groundwater Heads - Layer 3 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary Layer 3 GroundwaterHead (ft)High : 83.9931 Low : -19.1549 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 3.21 Historical Initial Groundwater Heads - Layer 4.mxd Figure 3-21Historical Initial Groundwater Heads - Layer 4 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Subbasin Boundary ECC Model Boundary Layer 4 GroundwaterHead (ft)High : 83.5049 Low : -9.60142 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ !( !( !(!(!( !( !( !(!(!( !( !(!( !( !( !( !( !( !( !( !(!(!( !(!(!( !( !(!(!( !( 5-39 5-22 1 JNJ 1BMW-140 1BMW-343 378097N1215428W001 378644N1215710W001 378823N1215723W001 378849N1214822W001 378871N1215744W001 379059N1215081W001 379143N1215624W001 379153N1215506W001 379513N1215704W001 380170N1218924W001 4AMW-152 5 Binn6 Byer Bethel Island Blossom Well Brentwood MW-14 Deep Brentwood MW-14 Int. Brentwood MW-14 Shallow Creekside MW Knightsen Knightsen School Irrigation (#2) South Park Stonecreek MW-160 Stonecreek MW-300 Stonecreek MW-360 Well #11 (4.61-A) Sources: Esri, HERE, Garmin, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo, © OpenStreetMap contributors, and the GIS User CommunityG:\ECCC_SWGW_Tracy\FLOW MODEL\GIS\ECCModel_CalibrationResiduals.mxd Figure 3-22Map of Groundwater Level Calibration Wells East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California 0 1 20.5 Miles ´ Explanation Wells Used forECCSim ModelCalibrationSimulated ModelLayer !(Layer 1 (12 Wells) !(Layer 2 (6 Wells) !(Layer 3 (6 Wells) !(Layer 4 (7 Wells) ECC IWFM Model ElementsB118 Basin Boundary SJV - East Contra Costa Subbasin X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.1 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 1.mxd Figure 4-1 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 1 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary HydraulicConductivity (ft/day)High : 310.95 Low : 0.0741767 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.2 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 2.mxd Figure 4-2 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 2 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary HydraulicConductivity (ft/day)High : 311.398 Low : -8.61789 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.3 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 3.mxd Figure 4-3 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 3 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary HydraulicConductivity (ft/day)High : 680.254 Low : -20.0458 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.4 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 4.mxd Figure 4-4 Calibrated Horizontal Hydraulic Conductivity (Kh) - Layer 4 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary HydraulicConductivity (ft/day)High : 941.775 Low : -43.5521 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.5 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 1.mxd Figure 4-5 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 1 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary HydraulicConductivity (ft/day)High : 15.913 Low : -0.128456 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.6 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 2.mxd Figure 4-6 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 2 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary HydraulicConductivity (ft/day)High : 2.95215 Low : -0.152939 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.7 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 3.mxd Figure 4-7 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 3 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary HydraulicConductivity (ft/day)High : 7.34655 Low : -0.377785 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.8 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 4.mxd Figure 4-8 Calibrated Vertical Hydraulic Conductivity (Kv) - Layer 4 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Subbasin Boundary ECC Model Boundary HydraulicConductivity (ft/day)High : 55.124 Low : -3.1382 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.9 Calibrated Specific Yield (Sy) - Layer 1.mxd Figure 4-9Calibrated Specific Yield (Sy) - Layer 1 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Subbasin Boundary ECC Model Boundary Specific YeildHigh : 0.114195 Low : 0.0719967 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.10 Calibrated Specific Yield (Sy) - Layer 2.mxd Figure 4-10Calibrated Specific Yield (Sy) - Layer 2 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary Specific YeildHigh : 0.114195 Low : 0.0719967 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.11 Calibrated Specific Yield (Sy) - Layer 3.mxd Figure 4-11Calibrated Specific Yield (Sy) - Layer 3 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Subbasin Boundary ECC Model Boundary Specific YeildHigh : 0.114195 Low : 0.0619967 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.12 Calibrated Specific Yield (Sy) - Layer 4.mxd Figure 4-12Calibrated Specific Yield (Sy) - Layer 4 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary Specific YieldHigh : 0.112849 Low : 0.0437451 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.13 Calibrated Specific Storage (SS) - Layer 1.mxd Figure 4-13Calibrated Specific Storage (SS) - Layer 1 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary Specific StorageHigh : 6.57551e-05 Low : 1.27637e-05 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.14 Calibrated Specific Storage (SS) - Layer 2.mxd Figure 4-14Calibrated Specific Storage (SS) - Layer 2 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Subbasin Boundary ECC Model Boundary Specific StorageHigh : 6.57551e-05 Low : 3.43351e-06 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.15 Calibrated Specific Storage (SS) - Layer 3.mxd Figure 4-15Calibrated Specific Storage (SS) - Layer 3 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Model Boundary ECC Subbasin Boundary Specific StorageHigh : 6.57551e-05 Low : -2.15259e-06 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.16 Calibrated Specific Storage (SS) - Layer 4.mxd Figure 4-16Calibrated Specific Storage (SS) - Layer 4 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation ECC Subbasin Boundary ECC Model Boundary Specific StorageHigh : 7.1532e-05 Low : -2.54884e-06 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ 020040060080010001200‐60 to ‐50‐50 to ‐40‐40 to ‐30‐30 to ‐20‐20 to ‐10‐10 to ‐5‐5 to 00 to 55 to 10 10 to 20 20 to 30 30 to 40 40 to 50 50 to 60 60 to 70 70 to 80Number of Groundwater Elevation  MeasurementsResidual (Simulated minus Observed Groundwater Elevation), feetHistogram of Residual (Simulated minus Observed) Groundwater Elevations for All ObservationsEast Contra Costa Groundwater‐Surface WaterSimulation Model (ECCSim) ReportFigure 4-17 02468101214‐40 to ‐30‐30 to ‐20‐20 to ‐10‐10 to ‐5‐5 to 00 to 55 to 10 10 to 20 20 to 30 30 to 40Number of Calibration WellsAverage Residual By Well (Simulated minus Observed Groundwater Elevation), feetHistogram of Average Residual (Simulated minus Observed) Groundwater Elevation by WellEast Contra Costa Groundwater‐Surface WaterSimulation Model (ECCSim) ReportFigure 4-18 ‐80‐60‐40‐20020406080‐80‐60‐40‐200 20406080Observed Groundwater Elevation (ft, msl)Residual (Simulated Minus Observed Groundwater Elevation), feetLayer 1Layer 2Layer 3Layer 41:1 LineSimulated vs. Observed Groundwater Elevations, By LayerEast Contra Costa Groundwater‐Surface WaterSimulation Model (ECCSim) ReportFigure 4-19 Figure 4-20Simulated vs. Observed Groundwater Elevations By Layer East Contra Costa Groundwater-Surface WaterSimulation Model (ECCSim) Report X:\2018\18-060 City of Brentwood - GSP Development\GIS\Model TM\Figure 4.20 Simulated vs. Observed Groundwater Elevations.mxd Layer 1 Layer 2 Layer 4Layer 3 ‐80‐60‐40‐20020406080‐80‐60‐40‐200 20406080Observed Groundwater Elevation (ft, msl)Residual (Simulated Minus Observed Groundwater Elevation), feetLayer 1Layer 2Layer 3Layer 4Residual (Simulated minus Observed) vs. Observed Groundwater Elevations, By LayerEast Contra Costa Groundwater‐Surface WaterSimulation Model (ECCSim) ReportFigure 4-21 Monitoring Protocols APPENDIX 6a DRAFT EAST CONTRA COSTA SUBBASIN GSP SEPTEMBER 2021 APPENDIX 6A - MONITORING PROTOCOLS LSCE 1 1 MONITORING PROTOCOLS 1.1 Protocols for Measuring Groundwater Levels  Measure depth to water in the well using procedures appropriate for the measuring device.  Equipment must be operated and maintained in accordance with manufacturer’s instructions.  Groundwater levels shall be measured to the nearest 0.1 foot relative to the Reference Point.   For measuring wells that are under pressure, allow a period of time for the groundwater levels to  stabilize. In these cases, multiple measurements shall be collected to ensure the well reached  equilibrium such that no significant changes in water level are observed. Every effort shall be  made to ensure that a representative stable depth to groundwater is recorded. If a well does not  stabilize, the quality of the value shall be appropriately qualified as a questionable measurement.   The groundwater elevation will be calculated using the following equation.  GWE = RPE − DTW  Where:  GWE = Groundwater Elevation in NAVD88 datum  RPE = Reference Point Elevation in NAVD88 datum  DTW = Depth to Water from the reference point   The measurements of depth to water shall be consistent in units of feet, to an accuracy of tenths  of feet or hundredths of feet.   The well caps or plugs shall be secured following depth to water measurement.   Groundwater level measurements are to be made on a semi‐annual basis during periods of  seasonal highs and lows.  1.1.1 Protocols for Recording Groundwater Level Measurements  The field personnel shall record the well identifier, date, time (24‐hour format), RPE, height of the  reference point above or below ground surface, DTW, GWE, and provide comments regarding any  factors that may influence the depth to water readings such as weather, nearby irrigation,  pumping, flooding, potential for tidal influence, or well condition. If there is a questionable  measurement or the measurement cannot be obtained, it shall be noted. Standardized field forms  shall be used for all data collection.   All data shall be entered into the GSP data management system (DMS) as soon as possible. Care  shall be taken to avoid data entry errors and the entries shall be checked by a second person.   Semi‐annual groundwater level data collected from the wells in the CASGEM network will be  submitted to DWR by March 31 (spring data) and October 31 (fall data) by the database manager.     DRAFT EAST CONTRA COSTA SUBBASIN GSP SEPTEMBER 2021 APPENDIX 6A - MONITORING PROTOCOLS LSCE 2 1.1.2 Protocols for Installing Pressure Transducers and Downloading Data  The field personnel must use an electronic sounder or chalked steel tape and follow the protocols  listed above to measure the groundwater level and calculate the groundwater elevation in the  monitoring well to properly program and reference the transducer. It is recommended that  transducers record measured groundwater levels to conserve data storage capacity; groundwater  elevations can be calculated at a later time after downloading.   The field personnel must note the well identifier, the associated transducer serial number,  transducer range, transducer accuracy, and cable serial number.   Transducers must be able to record groundwater levels with an accuracy of at least 0.1 foot.  Professional judgment will be used to ensure that the data being collected is meeting the Data  Quality Objectives (DQO) and that the instrument is capable. Consideration of the battery life,  data storage capacity, range of groundwater level fluctuations, and natural pressure drift of the  transducers shall be included in the evaluation.   The field personnel must note whether the pressure transducer uses a vented or non‐vented cable  for barometric compensation. Vented cables are preferred, but non‐vented units provide  accurate data if properly corrected for natural barometric pressure changes. This requires the  consistent logging of barometric pressures to coincide with measurement intervals.   Follow manufacturer specifications for installation, calibration, data logging intervals, battery life,  correction procedure (if non‐vented cables used), and anticipated life expectancy to assure that  DQOs are being met for the GSP.   Secure the cable to the well head with a well dock or another reliable method. Mark the cable at  the elevation of the reference point with tape or an indelible marker to verify that the cable has  not slipped.   The transducer data shall periodically be checked against manually measured groundwater levels  to monitor electronic drift or cable movement. This shall happen during routine site visits, at least  annually to maintain data integrity.    The data shall be downloaded as necessary to ensure no data is lost. Downloaded data shall be  entered into the GSP DMS following the quality assurance/quality control (QA/QC) program  established for the GSP. Data collected with non‐vented data logger cables shall be corrected for  atmospheric barometric pressure changes, as appropriate. After the field personnel is confident  that the transducer data have been safely downloaded and stored, the data shall be deleted from  the data logger to ensure that adequate data logger memory remains for new data.     DRAFT EAST CONTRA COSTA SUBBASIN GSP SEPTEMBER 2021 APPENDIX 6A - MONITORING PROTOCOLS LSCE 3 1.1.3 Protocols for Groundwater Storage Measurements Groundwater storage shall be determined from groundwater elevation measurements. Groundwater  elevation contours shall be created annually and compared to the groundwater contours generated in the  previous year. The change in groundwater elevation at each monitoring site will also be analyzed on  annual basis to understand where the greatest decline in storage is occurring spatially. For the comparison  of annual groundwater conditions, the highest groundwater elevations recorded in the spring of each year  will be used.   Where groundwater levels indicate a change in storage, storage change in the unconfined to semi‐  confined Shallow Zone will be calculated as follows:  ΔQs = (ΔH) x (Sy) x (A)  Where:  ΔQs = Change in Shallow Zone Storage   ΔH = change in groundwater elevation (or hydraulic head)   Sy = specific yield of the unconfined aquifer  A = surface area of the aquifer   Groundwater storage change in the semi‐confined to confined Deep Zone shall be calculated with the  equation below:  ΔQd = (ΔH) x (Ss x B) x (A)  Where:  ΔQd = Change in deep Zone Storage  ΔH = change in groundwater elevation (or hydraulic head)  Ss = specific storage of the confined aquifer  B = aquifer thickness  A = surface area of the aquifer  1.2 Protocols for Groundwater Quality Measurements including Seawater Intrusion Water quality monitoring of production wells that are part of municipal and other public water systems  are incorporated into the groundwater quality monitoring network. Data from these sources include initial  monitoring and ongoing compliance monitoring. The data is comprised of regulated primary and  secondary drinking water constituents from which a baseline of water quality conditions in the Deep  Aquifer water supply source is derived. Selected key constituents identified as having the potential to  influence sustainable management in the ECC Subbasin are discussed, along with baseline maps and  tables, under Basin Setting Section 3.5.5.  The key constituents are total dissolved solids (TDS), nitrate,  chloride, arsenic, boron, and mercury. While there may be localized constituents of concern, including  point‐source contamination sites, within GSAs, the key constituents are intended to satisfy monitoring for  the water quality degradation sustainability indicator. Annual monitoring of groundwater quality in new  and existing dedicated monitoring wells will include sampling and laboratory analysis of the key  constituents on an annual basis while recognizing that monitoring in the public supply sources may be less  frequent. At the 5‐year periodic evaluation (see Section 6.10), the monitoring frequency and the list of  key constituents will be assessed with respect to sustainable management. At that time, for example,  DRAFT EAST CONTRA COSTA SUBBASIN GSP SEPTEMBER 2021 APPENDIX 6A - MONITORING PROTOCOLS LSCE 4 monitoring frequency in the dedicated wells might be adjusted to coincide with drinking water compliance  monitoring frequency.  During sampling events, field parameters shall be measured and recorded. The field parameters shall  include electrical conductivity at 25 °C (EC) in μS/cm, pH, temperature (in °C), and dissolved oxygen (DO)  in mg/L.   The GSP monitoring program will utilize the following protocols for collecting groundwater quality  samples:   Prior to sampling, the analytical laboratory will be contacted to schedule laboratory time, obtain  appropriate sample containers, and clarify any sample holding times or sample preservation  requirements.   Verify well identification at the monitoring site (the well identifier may appear on the well housing  or the well casing).   In the case of wells with dedicated pumps, samples shall be collected at or near the wellhead  following purging.   Prior to sampling, the sampling port and sampling equipment shall be cleaned to remove any  contaminants. The equipment shall be decontaminated between each sampling locations or wells  to avoid cross‐contamination.   The groundwater elevation in the well shall be measured following appropriate protocols  described above in the groundwater level measuring protocols.   For any well not equipped with low‐flow or passive sampling equipment, an adequate volume of  water shall be purged from the well to ensure that the groundwater sample is representative of  ambient groundwater and not stagnant water in the well casing. Purging three well casing  volumes is generally considered adequate. Professional judgment will be employed to determine  the proper configuration of the sampling equipment with respect to well construction such that  a representative ambient groundwater sample is collected. If pumping causes a well to be  evacuated (go dry), document the condition and allow well to recover to at least 90% of original  water level prior to sampling.   Field parameters of pH, electrical conductivity and temperature shall be collected during purging  and prior to the collection of each sample. Field parameters monitored during the purging of the  well shall stabilize prior to sampling. Measurements of pH shall only be taken in the field;  laboratory pH analyses are typically unachievable due to short hold times. Other parameters, such  as Oxidation‐Reduction Potential (ORP), Dissolved Oxygen (DO) (in situ measurements  preferable), or turbidity, may also be useful for assessing purge conditions. All field instruments  shall be calibrated daily and evaluated for drift throughout the day.   Sample containers shall be labeled prior to sample collection. The sample label must include  sample ID (often well ID), sample date and time, sample personnel, sample location, preservative  used, and analytes and analytical method.  DRAFT EAST CONTRA COSTA SUBBASIN GSP SEPTEMBER 2021 APPENDIX 6A - MONITORING PROTOCOLS LSCE 5  Samples shall be collected under laminar flow conditions. This may require reducing pumping  rates prior to sample collection.   All samples requiring preservation must be preserved as soon as practically possible, ideally at the  time of sample collection. Ensure that samples are appropriately filtered as recommended for the  specific analyte. Entrained solids can be dissolved by preservative leading to inconsistent results  of dissolve analytes. Specifically, samples to be analyzed for metals shall be field filtered prior to  preservation; do not collect an unfiltered sample in a preserved container.    Samples should be chilled and maintained at 4 °C to prevent degradation of the sample. The  laboratory’s Quality Assurance Management Plan shall be followed.   Samples must be shipped under chain of custody documentation to the appropriate laboratory  promptly to avoid violating holding time restrictions.   Groundwater quality samples shall be collected annually in new wells per Table 6‐8.   All data shall be entered into the GSP DMS as soon as possible. Data entries should be checked by  a second person for quality assurance.  1.3 Protocols for Groundwater Pumping Measurements Measurements of groundwater pumping are conducted in all public supply wells but pumping at privately‐ owned domestic and irrigation wells are not monitored. The following protocols shall be followed when  recording groundwater pumping totals:   Groundwater pumping amounts shall be reported in units of acre‐feet on monthly basis.   Amounts are to be determined by a totalizer/flowmeter or calculated using electric consumption  records.    Groundwater pumping totals shall be sourced from the well owner.   Meters shall be periodically checked for accuracy utilizing manufacturers recommendations. If  necessary, meters shall be periodically calibrated according to manufacturer specifications.    All data shall be entered into the GSP DMS annually.   1.4 Protocols for Subsidence Measurements Subsidence in the ECC Subbasin will be evaluated using the available data from UNAVCO PBO stations.  The GSAs will not be responsible for collecting subsidence data. Available subsidence data from the four  selected UNAVCO PBO stations (P256, P230, P248 and P257) will be downloaded annually and entered  into the GSP DMS for inclusion in an Annual Report.  1.5 Protocols for Interconnected Surface Water Measurements Shallow groundwater levels associated with Interconnected surface water measurements will be made by  collecting groundwater elevation measurements  from adjacent (or nested) Shallow and Deep Zone wells.  Protocols for groundwater level measuring and groundwater level recording shall be followed when  measuring and recording groundwater levels.  DRAFT EAST CONTRA COSTA SUBBASIN GSP SEPTEMBER 2021 APPENDIX 6A - MONITORING PROTOCOLS LSCE 6 Vertical hydraulic gradient associated with the groundwater‐surface water system will be calculated   as follows:  Δh = (h1 – h2) / (m1 – m2)  Where:  Δh = vertical gradient  h1 and h2 = groundwater elevation in deep and shallow wells, respectively  m1 and m2 = mid‐point elevations of the screens in deep and shallow wells, respectively  Surface flow data of interconnected surface waters shall be downloaded by the database manager from  public databases for annual reporting. Groundwater elevations, calculated vertical gradients, surface  water flow rates (daily or monthly mean flow in cubic feet per second) and stage of surface water  (elevation relative to NAVD88) shall be entered into the GSP DMS on an annual basis.  Representative Monitoring Sites Minimum Threshold, Measurable Objectives for Chronic Lowering of Groundwater Levels APPENDIX 7a Appendix7a-1Measurable Objectives and Minimum Thresholds- Antioch MW-15 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 7a-1 MO MT Graphic Antioch MW-15.mxd Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities Reference Point of Elevation 4.12 from mean sea level (msl) Perforations (Screen Interval) 5-15 ft bgs Casing Concord Antioch Contra Costa County Solano County San Joaquin County Sacramento County Alameda CountyOld R iver OldRiver San Joaquin River Explanation Water Year Hydrologic Classification 1 1. Source of Water Year Type: https://cdec.water.ca.gov/reportapp/javareports?name=WSIHIST Total Depth 30 ft bgs Measurable Objective: 0.62 ft msl Minimum Threshold: -9 ft msl Note that the MT and MO may be revised as additional data becomes available. Appendix7a-2Measurable Objectives and Minimum Thresholds- 5 Binn East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 7a-2 MO MT Graphic 5Binn.mxd Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities Reference Point of Elevation 23.46 from mean sea level (msl) Perforations (Screen Interval) Unknown Casing Concord Antioch Contra Costa County Solano County San Joaquin County Sacramento County Alameda CountyOld R iver OldRiver San Joaquin River Explanation Water Year Hydrologic Classification 1 1. Source of Water Year Type: https://cdec.water.ca.gov/reportapp/javareports?name=WSIHIST Total Depth 45 ft bgs Measurable Objective: 15.62 ft msl Minimum Threshold: -4 ft msl Appendix 7a-3Measurable Objectives and Minimum Thresholds- BG-2 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 7a-3 MO MT Graphic BG-2.mxd Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities Reference Point of Elevation 62.09 from mean sea level (msl) Perforations (Screen Interval) 22.5-37.5 ft bgs Casing Concord Antioch Contra Costa County Solano County San Joaquin County Sacramento County Alameda CountyOld R iver OldRiver San Joaquin River Explanation Water Year Hydrologic Classification 1 1. Source of Water Year Type: https://cdec.water.ca.gov/reportapp/javareports?name=WSIHIST Total Depth 37.5 ft bgs Measurable Objective: 43.53 ft msl Minimum Threshold: 32 ft msl Appendix7a-4Measurable Objectives and Minimum Thresholds- DWD MW-30 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 7a-4 MO MT Graphic DWD MW-30.mxd Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities Reference Point of Elevation 7.26 from mean sea level (msl) Perforations (Screen Interval) 20-30 ft bgs Casing Concord Antioch Contra Costa County Solano County San Joaquin County Sacramento County Alameda CountyOld R iver OldRiver San Joaquin River Explanation Water Year Hydrologic Classification 1 1. Source of Water Year Type: https://cdec.water.ca.gov/reportapp/javareports?name=WSIHIST Total Depth 30 ft bgs Measurable Objective: 1 ft msl Minimum Threshold: -9 ft msl Note that the MT and MO may be revised as additional data becomes available. Appendix7a-5Measurable Objectives and Minimum Thresholds-ECCID Well #11 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 7a-5 MO MT Graphic Well11 ECCID.mxd Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities Reference Point of Elevation 55.5 from mean sea level (msl) Perforations (Screen Interval) 50-100 ft bgs Casing Concord Antioch Contra Costa County Solano County San Joaquin County Sacramento County Alameda CountyOld R iver OldRiver San Joaquin River Explanation Water Year Hydrologic Classification 1 1. Source of Water Year Type: https://cdec.water.ca.gov/reportapp/javareports?name=WSIHIST Total Depth 100 ft bgs Measurable Objective: 39.51 ft msl Minimum Threshold: 12 ft msl Appendix7a-6Measurable Objectives and Minimum Thresholds- Antioch MW-90 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 7a-6 MO MT Graphic Antioch MW-90.mxd Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities Reference Point of Elevation 4.77 from mean sea level (msl) Perforations (Screen Interval) 75-85 Casing Concord Antioch Contra Costa County Solano County San Joaquin County Sacramento County Alameda CountyOld R iver OldRiver San Joaquin River Explanation Water Year Hydrologic Classification 1 1. Source of Water Year Type: https://cdec.water.ca.gov/reportapp/javareports?name=WSIHIST Total Depth 90 ft bgs Measurable Objective: -1 ft msl Minimum Threshold: -11 ft msl Note that the MT and MO may be revised as additional data becomes available. Appendix7a-7Measurable Objectives and Minimum Thresholds-Brentwood MW-14 Int. East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 7a-7 MO MT Graphic Brentwood.mxd Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities Reference Point of Elevation 72.76 from mean sea level (msl) Perforations (Screen Interval) 285-315 ft bgs Casing Concord Antioch Contra Costa County Solano County San Joaquin County Sacramento County Alameda CountyOld R iver OldRiver San Joaquin River Explanation Water Year Hydrologic Classification 1 1. Source of Water Year Type: https://cdec.water.ca.gov/reportapp/javareports?name=WSIHIST Total Depth 340 ft bgs Measurable Objective: 15.62 ft msl Minimum Threshold: -48 ft msl Appendix7a-8Measurable Objectives and Minimum Thresholds-Bethel-Willow Rd East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 7a-8 MO MT Graphic Bethel-Willow Rd.mxd Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities Reference Point of Elevation 4.69 from mean sea level (msl) Perforations (Screen Interval) 230-260 ft bgs Casing Concord Antioch Contra Costa County Solano County San Joaquin County Sacramento County Alameda CountyOld R iver OldRiver San Joaquin River Explanation Water Year Hydrologic Classification 1 1. Source of Water Year Type: https://cdec.water.ca.gov/reportapp/javareports?name=WSIHIST Total Depth 260 ft bgs Measurable Objective: -3 ft msl Minimum Threshold: -15 ft msl Note that the MT and MO may be revised as additional data becomes available. Appendix7a-9Measurable Objectives and Minimum Thresholds- Stonecreek MW-300 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 7a-9 MO MT Graphic Stonecreek MW-300.mxd Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities Reference Point of Elevation 30.47 from mean sea level (msl) Perforations (Screen Interval) 230-240, 280-290 ft bgs Casing Concord Antioch Contra Costa County Solano County San Joaquin County Sacramento County Alameda CountyOld R iver OldRiver San Joaquin River Explanation Water Year Hydrologic Classification 1 1. Source of Water Year Type: https://cdec.water.ca.gov/reportapp/javareports?name=WSIHIST Total Depth 300 ft bgs Measurable Objective: -1.71 ft msl Minimum Threshold: -37 ft msl Appendix7a-10Measurable Objectives and Minimum Thresholds- 4AMW-357 East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California X:\2018\18-060 City of Brentwood - GSP Development\GIS\Appendix 7a-10 MO MT Graphic 4AM-357.mxd Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities Reference Point of Elevation 11.54 from mean sea level (msl) Perforations (Screen Interval) 307-347 ft bgs Casing Concord Antioch Contra Costa County Solano County San Joaquin County Sacramento County Alameda CountyOld R iver OldRiver San Joaquin River Explanation Water Year Hydrologic Classification 1 1. Source of Water Year Type: https://cdec.water.ca.gov/reportapp/javareports?name=WSIHIST Total Depth 357 ft bgs Measurable Objective: -21.45 ft msl Minimum Threshold: -107 ft msl Comparison of Domestic Wells and Depth to Minimum Threshold APPENDIX 7b !( !(!(!(!(!(!(!( !(!(!(!(!(!( !(!(!( !(!(!(!(!(!(!(!(!(!(!( !( !( !(!(!(!(!(!(!(!(!( !( !( !(!( !( !( !( !(!( Los Vaqueros Reservoir Clifton Court Forebay Antioch Reservoir Marsh Creek Reservoir Contra Loma Reservoir Big Break Franks Tract Old RiverKellogg CreekBrushy CreekMar s h C r e e k San Joaquin RiverX:\2018\18-060 City of Brentwood - GSP Development\GIS\Figure 7.XX Comparison of Domestic Wells and Depth.mxd Appendix7b-1 Comparison of Domestic Wells and Depth to Minimum Threshold East Contra Costa Subbasin Groundwater Sustainability PlanContra Costa County, California Explanation !(Representative Shallow Monitoring Point !(Wells with potential to go dry Domestic wells since 1970 ECC Subbasin Boundary Surface Interpolatedfrom RMS WaterLevel MT Values Depth (ft) < 10 11 - 30 31 - 50 51 - 70 71 - 90 91 - 110 111 - 130 131 - 160 161 - 180 > 180 Data sources: USGS - waterways, DEM; DWR - subbasin boundaries; US Census - cities, Contra Costa County-Legal Delta Boundary 0 1 2 30.5 Miles ´ East Contra Costa Groundwater Sustainability Plan Implementation Budget APPENDIX 9a Category 2020/2022 Annual 5-Year Community Outreach & Education Quarterly GSA meeting (4 times/year, consultant, $200* 2hrs=$1,600). Plus: agendas, meeting notes and setting up meetings. $5,000 Update ECC Online Visualization for public viewing of most recent groundwater levels (2 times/year*$1,000 each) $2,000 Board notifications (quarterly, 2 hours x $200=$400x4=1,600each)$1,600 Intra/Inter subbasin coordination (by GSA only for minimum of range) Newsletters to interested parties and others (by GSA for minimum of range) Update website (by GSA for minimum of range) Total $10,000 ‐ $25,000 GSP Monitoring and Data Management Monitoring1 and Well Maintenance Groundwater Elevation: nine new wells, take manual measurements 2x/yr, check SCADA equipment, maintenance is not expected the first two years and will be costed as the need arises. $4,000 $4,000 Groundwater Quality: nine new wells purged and sampled annually (one person, 3 days of 12 hours each=$7,000) and analyses describe in Section 6 (TDS, nitrate, chloride, arsenic, boron, and mercury, $2,000). $9,000 Total Monitoring and Well Maintenance $13,000 Data Management Data collection from online sources and GSAs. Includes groundwater levels, groundwater extractions, streamflow, water quality (groundwater and surface water), Geotracker, other. $20,000 Data Management System update with data from all sources.$5,000 Data analysis including graphing and upload 2x/yr. to DWR Portal $7,000 Total Data Management $32,000 Total GSP Monitoring and Data Management $45,000 GSP Reporting GSP Annual Reporting2 Prepare excel files of: groundwater extraction (by GSA and methods), surface water supply, total water use, change in storage, and elements guide. $20,000 $10,000 ‐ $20,000 Prepare figures: map of the subbasin and GSA boundaries, groundwater elevation contours by zone (2/yr.), hydrographs for basin-wide wells, map of location and volume of extractions, map of changes in GW storage by aquifer, graph of historical GW use by water year type. $15,000 $8,000 ‐ $15,000 Appendix 9a East Contra Costa Groundwater Sustainability Plan Implementation Budget Category 2020/2022 Annual 5-Year Table 1 Draft East Contra Costa Groundwater Sustainability Plan Implementation Budget Executive summary and narrative describing findings and recommendations for the period.$12,000 $12,000 Upload to Annual Report Module/Report Submittal $3,000 $3,000 Total GSP Annual Reporting $50,000 $33,000 ‐ $50,000 GSP Five Year Update to include: Basin Setting Evaluation: any changes? Evaluate new information from the last 5 years.$30,000 Monitoring Network: evaluation of network and description of data gaps and plan for new facilities if necessary. $40,000 ‐ $75000 Current Groundwater Conditions for each sustainability indicator. Includes update of subbasin model.3 $50,000 ‐ $250000 Evaluation of Sustainability Management Criteria: revisions proposed if necessary. Progress toward meeting sustainability goal. $20,000 ‐ $35,000 Implementation of Projects evaluated $5,000 ‐ $30,000 Other: Relevant Actions taken by GSAs impacting the implementation of the GSP. Enforcement or legal actions by the GSA, GSP amendments to the GSP. $5,000 ‐ $30,000 Outreach and Coordination specific to 5-year update: of GSAs, adjacent subbasins, and others $20,000 ‐$50,000 Total GSP Five Year Update $140,000 ‐  $500,000 Grant Writing $25,000 SGMA: to address comments from DWR on the GSP $15,000 Contingency (10%)10% 3. The minimum modeling amount covers a one-time effort after 5 years to :extend the future scenarios, update surface water deliveries, pumping, precipitation and ET data; recalibration if necessary. Estimate 5 weeks x 40hrs x $200 = $8,000. Includes figure production, report writing for a total of $20,000. The maximum modeling amount is an expanded effort totalling $220,000 1. Assumes that each member agency will continue to monitor its own wells for groundwater levels and quality using its own resources. Only groundwater levels and quality from the nine new monitoring wells, that would not otherwise be conducted by the individual member agencies, is assumed to be covered by the ECC member agencies. 2. Assumes the first annual report covers 2020 to 2022. Summary List of Public Meetings and Outreach APPENDIX 10a Appendix 10a Summary List of Public Meetings and Outreach (as of 08.21.2021) Jurisdiction Topics covered in Outreach Outreach Method Presenter Audience Number of People Date Antioch Notice of Public Hearing Newspaper Scott Buenting General Public 10,000 3/9/17 Antioch Notice of Public Hearing Newspaper Scott Buenting General Public 10,000 3/16/17 Antioch Public hearing and authorization to execute a MOU for GSP development Council Report Scott Buenting General Public 200   3/28/17 Antioch Update on GSA and GSP status Council Report Scott Buenting General Public 200 11/13/18 Antioch Update and First Amendment to GSP MOU Council Report Scott Buenting General Public 200 11/28/17 Antioch Info on how to receive more GSA/GSP/ SGMA info Utility Bill Tracy Shearer General Public 33,000 10/1/19 Antioch Info on how to receive more GSA/GSP/ SGMA info Utility Bill Tracy Shearer General Public 33,000 11/15/19 Antioch GSA Update and Second Amendment to GSP MOU Council Report Scott Buenting General Public 200 1/28/20 Antioch GSA Update Council Report Tracy Shearer General Public 200 10/27/20 Antioch GSP Workshop notification Utility Bill Scott Buenting General Public 33,000 6/1/21 Antioch GSP Workshop notification City Website Scott Buenting General Public 25 6/21/21 BBID GSP development updates BBID webpage on SGMA (https://bbid.org/governance/ groundwater-management/) Nick Janes General Public 300 Ongoing BBID comments sought on GSP development Web posting Nick Janes General Public 300 5/7/2020 BBID GSP development updates Board report Nick Janes General Public 10 6/17/2020 BBID Notice of Public Meeting on Draft ECC GSP Web posting Nick Janes General Public 300 6/26/2020 BBID GSP development updates Board report Nick Janes General Public 10 9/29/2020 BBID Notice of Public Meeting on Draft ECC GSP Web posting Nick Janes General Public 300 11/30/2020 BBID GSP development updates Board report Nick Janes General Public 10 1/19/2021 BBID GSP development updates Board report Nick Janes General Public 10 4/20/21 BBID Notice of Public Meeting on Draft ECC GSP Web posting Nick Janes General Public 300 6/11/2021 BBID GSP development updates Board report Nick Janes General Public 10 6/29/2021  Jurisdiction Topics covered in Outreach Outreach Method Presenter Audience Number of People Date Brentwood BBM, East County MOU, SGMA, GSA, GSP Board Report Eric Brennan General Public 50 3/28/2017 Brentwood GSA MOU and Amendment ‐ SGMA, GSA, GSP, Prop 1 Grant Board Report Eric Brennan General Public 50 12/12/2017 Brentwood Basin Boundary Modification (BBM), SGMA Board Report Eric Brennan General Public 50 5/8/2018 Brentwood SGMA, City's GSA Formation, GSP Development  fifty page views per month closing date 8.16.21  on going 1,650 11/1/2018 Brentwood GSP Development Information Utility Bill  General Public 20,300 10/1/2019 Brentwood BBM, Tracy Subbasin, ECCC Subbasin, GSP Development, San Joaquin Project Agreement  Board Report Eric Brennan General Public 50 10.22.2019 Brentwood GSP Development Information Utility Bill General Public 20,300 11/1/2019 Brentwood SGMA ‐GSP Update Provided SGMA / GSP update to East County Water Management Association Governing Board Meeting Eric Brennan Public water systems 25 5/14/2020 Brentwood GSP Chapters 3 & 4 Website Team General Public 1,000 12/1/2020 Brentwood GSP Chapters 6, 7, 8 ,9 Website Team General Public 1,000 8/18/2021 Brentwood GSP Chapters 1 & 2 Website N/A General Public 1,000  CCC GSP Progress and Draft Chapters Available to review Public Meeting before the CCC Transportation, Water, Infrastructure Committee Ryan Hernandez General Public 17 2/8/2021 CCC Public Review of Section 6 Draft and Survey Website Ryan Hernandez General Public   4/2/2021 CCC Public Notice of Section 6 Draft and Optional Survey District 3 News ‐ Weekly E‐newsletter Supervisor Diane Burgis General Public 1,400  4/8/2021 CCC Public Review Notice of Section 6 and Survey District 3 News ‐ Weekly E‐newsletter Supervisor Diane Burgis General Public 1,400 4/15/2021 CCC Public Review of Section 6 Draft and optional Survey  Website Supervisor Diane Burgis General Public   4/15/2021 CCC Notice of Public Meeting on Draft ECC GSP District 3 News ‐ Weekly E‐newsletter Supervisor Diane Burgis General Public 1,400 6/17/2021 CCC Public Review Notice of Sections 7‐9 and Survey Website Announcement/Content Team General Public   7/22/2021  Jurisdiction Topics covered in Outreach Outreach Method Presenter Audience Number of People Date CCC Public Review Notice of Sections 7‐9 and Survey District 3 News ‐ Weekly E‐newsletter Supervisor Diane Burgis General Public 1,400 7/29/2021 CCC Public Review Notice of Sections 7‐9 and Survey District 3 News ‐ Weekly E‐newsletter Supervisor Diane Burgis General Public 1,400 8/5/2021 CCC GSP Sections 7, 8 and 9 Public Meeting before the CCC Transportation, Water, Infrastructure Committee Ryan Hernandez General Public 16 8/9/2021 CCC Public Review Notice of Sections 7‐9 and Survey District 3 News ‐ Weekly E‐newsletter Supervisor Diane Burgis General Public 1,400 8/12/2021 Diablo WD Getting the public involved Utility Bill  General Public 5,000 10/1/2019 Diablo WD Prop 68 Letter of Support and GSP Update Board Report Dan Muelrath General Public 10 10/23/2019 Diablo WD GSP development status and Amended MOU adoption Board Report Dan Muelrath General Public 10 1/22/2020 Diablo WD DRAFT GROUNDWATER SUSTAINABILITY PLAN AND PUBLIC MEETING Website General Public 50 7/6/2020 Diablo WD Recap of July's public workshop Directors Report Directors Seger and Pastor General Public 10 7/22/2020 Diablo WD GSP Plan Update Board Report  General Public 10 8/26/2020 Diablo WD GSP Update Board Report  General Public 10 10/28/2020 Diablo WD GSP Plan Overview and Update and GSP Policy Board Report  General Public 50 2/17/2021 Diablo WD GSP Protection Board Report  General Public 15 3/10/2021 Diablo WD GSP Survey E‐Newsletter  General Public 5,600 3/17/2021 Diablo WD Public Comment Period for GSP Facebook post linking to article  General Public 200 4/16/2021 Diablo WD GSP Board Report Dan Muelrath General Public 20 5/10/2021 Diablo WD GSP Presentation Sierra Club presentation Dan Muelrath Enviros/NGOs 10 6/10/2021 Diablo WD GSP Public Workshop Website  General Public    Diablo WD GSP Chapter 7, 8, 9 Website  General Public 1,000  Diablo WD GSP Workshop Facebook post  General Public 200  Diablo WD GSP Public Notice posted notice of public meeting  General Public   Diablo WD GSP Public Hearing Notice  Website  General Public 40  Diablo WD GSP Workshop Website  General Public 40  Diablo WD Special Board Meeting regarding groundwater Website  General Public 50   Jurisdiction Topics covered in Outreach Outreach Method Presenter Audience Number of People Date sustainability and future planning efforts  Diablo WD GSA Education Website  General Public 50  Diablo WD GSP Outreach  Website  General Public 50  Diablo WD Groundwater Sustainability Plan Update Website  General Public 50  Diablo WD East Contra Costa Sub basin public workshop  Website  General Public 50  Discovery Bay  Citizen Comments to Draft Chapters 1 & 2 Website Michael Davies General Public 176  Discovery Bay  Overview of GSAs and GSP Website  General Public 176  Discovery Bay  Overview of GSAs and GSP Utility Bill  General Public 6,200  ECCID Basin Boundary Modification 2020 GSP Scope and Budget Working Group Minutes Board Report Pat Corey General Public 50 2/12/2019 ECCID Basin Boundary Modification‐ Update 2020 GSP Scope/Budget approval Board Report Pat Corey General Public 50 3/19/2019 ECCID General GSP plan update Grant Funding Update Board Report Aaron Trott General Public 50 11/19/2019 ECCID General GSP plan update Grant Funding Update Board Report Aaron Trott General Public 50 12/10/2019 ECCID GSP Draft Section 3 open for comment, July 9th Public Workshop/ Outcome review.  Board Report Aaron Trott General Public 50 1/11/2020 ECCID Amended MOU update Board Report Aaron Trott General Public 50 1/14/2020 ECCID DRAFT GROUNDWATER SUSTAINABILITY PLAN AND PUBLIC MEETING Website Announcement/Content Aaron Trott General Public 250 1/15/2020 ECCID Amended and restated MOU Board Report Aaron Trott Agricultural users 8 3/9/2020 ECCID Board update  Board Report Aaron Trott Agricultural users 10 5/12/2020 ECCID GSP development status, Budget Update, Public outreach meeting schedule/ agenda Board Report Aaron Trott General Public 50 6/9/2020  Jurisdiction Topics covered in Outreach Outreach Method Presenter Audience Number of People Date ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 500 7/14/2020 ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 500 8/13/2020 ECCID GSP Draft Section 4 in development, working group update. Board Report Aaron Trott General Public 50 9/8/2020 ECCID ECC Groundwater Sustainability Plan Update Website Announcement/Content Aaron Trott General Public 250 9/15/2020 ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 500 9/16/2020 ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 500 10/12/2020 ECCID GSP Draft Section 4 in development, reviewed elements. Board Report Aaron Trott General Public 50 10/13/2020 ECCID GSP Draft Section 4 near completion, reviewed status and working group update. Board Report Aaron Trott General Public 50 11/10/2020 ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 500 11/12/2020 ECCID Draft Sections 4 Website Update Website Announcement/Content Aaron Trott General Public 250 11/20/2020 ECCID GSP Draft Section 4 Posted for public comment, reviewed budget, and GSP status. Board Report Aaron Trott General Public 20 12/8/2020 ECCID GSP Draft Section 4 Posted for public comment, reviewed budget, and GSP status. Board Report Aaron Trott General Public 20 12/8/2020 ECCID GSP Draft Section 6 in development, reviewed budget, and GSP status. Board Report Aaron Trott General Public 50 1/12/2021  Jurisdiction Topics covered in Outreach Outreach Method Presenter Audience Number of People Date ECCID Draft Sections 6 Website Update Website Announcement/Content Aaron Trott General Public 250 3/1/2021 ECCID GSP Draft Chapter 1‐4 & 6 posted for public comment, GSP Draft Sections 5‐9 in development, Reviewed draft GSP adoption schedule.  Board Report Aaron Trott General Public 50 3/10/2021 ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 500 3/17/2021 ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 500 4/15/2021 ECCID GSP Draft Section 7,8,9 in development, reviewed budget, and GSP status Board Report Aaron Trott General Public 50 5/12/2021 ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 500 5/12/2021 ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 500 6/16/2021 ECCID DRAFT GROUNDWATER SUSTAINABILITY PLAN ANNOUNCEMENT FOR JUNE‐23 PUBLIC MEETING Website Aaron Trott General Public 50 6/18/2021 ECCID Draft Sections 7,8,9 Website Update Request for Chapter Review Aaron Trott General Public 50 6/18/2021 ECCID General GSP status and review June‐23  public outreach Workshop. Board Report Aaron Trott General Public 50 7/14/2021 ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 500 7/14/2021 ECCID Section 10 status review, General GSP status and upcoming September 14 Workshop. Board Report Aaron Trott General Public 50 8/11/2021  Jurisdiction Topics covered in Outreach Outreach Method Presenter Audience Number of People Date ECCID Info on how to receive more GSA/GSP/ SGMA info Utility Bill  General Public 1,500 8/16/2021 ECCID DRAFT GROUNDWATER SUSTAINABILITY PLAN ANNOUNCEMENT FOR SEPTEMBER 14 PUBLIC WORKSHOP Website Aaron Trott General Public 50 8/18/2021 General Public Review Notice and Public Meeting, Sections 1 and 2 East Contra Costa News Team General Public 4,792 6/19/2020 General GSP Public Meeting and Review of Draft Sections 1 and 2 of GSP Brentwood Press Team General Public 100,000 6/19/2020 General GSP Intro to SGMA and the ECC Subbasin and GSP. Status and findings of technical work. Public workshop Team General Public 33 7/9/2020 General Public Review Notice of Sections 3 and 4 East County News Team General Public 4,792 11/21/2020 General Public Review Notice of Section 6 and Survey East County News Team General Public 4,792 4/1/2021 General Notice of Public Meeting on Draft ECC GSP East County News Team General Public 4,792 6/12/2021 General Notice of Public Meeting ECC GSP Brentwood Press Team General Public 100,000 6/18/2021 General Intro to SGMA and the ECC Subbasin and GSP. Status and findings of technical work. Public workshop Working Group, Consultant Team, and Supervisor Burgis General Public 47 6/23/2021 General Public Review Notice Sections 7‐9 and Survey East County News Team General Public 4,792 7/23/2021 General GSP Public Notice of Section 6 Draft and Optional Survey Interested Party List Team Email Interested Parties List 126 4/13/2021 General GSP Intro to SGMA and the ECC Subbasin and GSP. Status and findings of technical work. Public workshop Team General Public 47 6/23/2021 General GSP Public Review of Sections 3 and 4 of Draft GSP Interested Party List Team Email Interested Parties List 132 11/24/2021  Jurisdiction Topics covered in Outreach Outreach Method Presenter Audience Number of People Date          TOTAL  424,413    Notes: Antioch=City of Antioch; BBID=Byron‐Bethany Irrigation District; Brentwood=City of Brentwood; CCC=Contra Costa County; Diablo WD=Diablo Water District; Discovery Bay=Town of Discovery Bay; ECCID=East Contra Costa Irrigation District.  Summary of Public Comments on the Draft ECC GSP and Responses APPENDIX 10b     1 ECC GSP – Section Review ON‐LINE COMMENTS Section Date From Comment Notes 6 05.11.21 Katherine Perez Nototomne Cultural Preservation Presented Information is somewhat clear. Our interest is in protecting Cultural Resources. We need to know if there has been a literature search and if so can you please forward that to us. We would like to offer Mitigation Measures from the perspective of the Native Americans. We would like to see cultural awareness and pre‐construction training from the perspective of Native Americans before any ground disturbance accurse. We would like to see some archaeological testing implemented to determine cultural sensitivity and be included in that process. Etc. Contacted by Lisa Beutler. May be a need for follow‐up. 4 05.11.21 Jody London Contra Costa County I am the Sustainability Coordinator for Contra Costa County, in charge of implementation of the County's Climate Action Plan. The report does not in my opinion do enough to describe the coming reality of drought combined with increased heat and sea level rise.  I find it hard to believe that with expected population increases there will be sufficient conservation to meet water demand.   I didn't see any mention of the Adapting to Rising Tides studies.  It is highly likely that water treatment facilities will be impacted by rising water levels in the delta. Not to mention that Bethel Island and Discovery Bay could be flooded by 2050.    At the time this comment was posted, Section 5 Water Budget was not yet posted that considers climate change and sea level rise. Also, the potential for an increase in salinity baywater intrusion is discuss in Section 3.      2 Section Date From Comment Notes The report also does not discuss the possibility of increasing salinity from the intrusion of waters from the Bay.  My recommendation is the report be reviewed and amended by an entity that is more familiar with the realities of climate change and water supply, like the Pacific Institute.         3  Questions and Comments Received  During East Contra Costa Subbasin Public Workshops  Workshop Date Commenter Comment Response July 9, 2020 Dan Muelrath, Diablo Water District General Manager Has subsidence been documented in the East Contra Costa Subbasin? Not that we know of, but we are still analyzing and gathering data. July 9, 2020 Liz Elias, Attendee Are the GSP Working Group meetings open to the public? Not right now, but the public is invited to attend GSA Board Meetings. That’s something we can take back to the working group. Note, no formal decisions are made at working group meeting. July 9, 2020 Karen Converse, Attendee How were GSAs formed? Was this a “mandated” structure, or did municipalities decide themselves to form a GSA? Not everyone can become a GSA, SGMA requires that an entity has existing land use authority and/or water supply authority. It was determined early by the county, cities, and water districts who was using groundwater and what the boundaries would be. July 9, 2020 Campbell Ingram, Sacramento San Joaquin Delta Conservancy Executive Director Looking into the future at places like the City of Oakley, Bethel Island, etc., how does sea level rise relate to seawater intrusion?  We recognize it’s important to have a monitoring network in place to look at both groundwater levels and water quality. Levels by themselves don’t tell the whole picture. Through modeling, we will look at conditions 50 years out which will include sea level. Modeling will show where there are data gaps and a plan developed for additional monitoring needs. July 9, 2020 Dan Muelrath, Diablo Water District General Manager What about the delta...is the sea water line moving farther inland?  We are looking at groundwater‐surface water interaction, including salinity, through monitoring. If there are areas that have additional salinity occurring as a result of sea level rise or groundwater development activities, that’s something we want to know. It will provide an      4 Workshop Date Commenter Comment Response important piece of information for adaptive management. July 9, 2020 Liz Elias, Attendee What procedures, requirements, precautions will be put in place to prevent developers from overusing the supply and urban development? The GSAs’ powers and authorities are determined locally. DWR likes to emphasize that SGMA is not intended to solve everything, it would not supersede County Plans. GSAs could look at how groundwater pumping would impact the GSP in terms of measurable objectives.  In the County General Plan, there is an urban limit line. How it relates to groundwater and management? Those are the questions we are trying to ask. The GSAs want to track development and want to thoughtfully respond. The cities also have General Plans, I’m not familiar if they have urban limit lines.  July 9, 2020 Campbell Ingram, Sacramento San Joaquin Delta Conservancy Executive Director Subsidence is a problem on the islands due to microbial oxidation, but not due to groundwater management and or depletion. Because these areas are in the basin, it would be good to make that distinction. We have additional information from previously worked with the Water Foundation, DWR, and USGS, on land subsidence on all of California. July 9, 2020 Liz Elias, Attendee Will you monitor private wells? Or is there a way to keep track of what’s happening with that water? The GSAs are trying to use public wells for monitoring, not trying to monitor private wells unless a private well owner volunteers. The GSAs have established a monitoring network to maintain the continued health of the basin, but monitoring private wells is not something we are currently considering. De minimis user (well that pumps less than 2 acre‐feet per year) are exempt from SGMA.      5 Workshop Date Commenter Comment Response  July 9, 2020 Jon Duta, Well Owner I have a small water system (well) that feeds an apartment in a rural area. What kind of restrictions may be placed on my system? Sounds like you are already complying with the county’s well permitting program. The GSAs are looking to maintain the current requirements. No changes are being proposed and we invite you to participate in the future.  Follow‐up Question from John Duta: The well gets tested monthly, would the results be useful for GSP process? Yes, it would be helpful, thank you so much.  July 9, 2020 Liz Elias, Attendee I'm just wondering about the threat of some of the oil drilling that's going on. And there seems to always be accidents associated, and that seems like a threat to groundwater. For oil and gas well drilling, they have to meet criteria in the zoning ordinance such as land use permit. We would need to look into regulations to see if there is anything SGMA would allow us to do anything about that. July 9, 2020 Paul Seger Diablo Water District Director SGMA provides an opportunity to have a public advisory committee, however he hasn’t seen that discussed or brought up. Are people in community interested in participating in a more formal way? Has that been discussed previously? This topic is related to a stakeholder process‐determined by GSAs. GSAs determine how they want stakeholders engaged. The GSAs sent out some surveys last year. They did not receive a lot of responses. The responses received said, “keep me posted when you have something to tell me”. There is no barrier to doing a public advisory committee; it can be accommodated.  Follow‐up Question from Paul Seger: East Bay Municipal District has something like this laid out in their plan, is this something that should be commented by the 20th? You could comment on it. Ryan could bring it up to the GSP Working Group and then work with Lisa on how to go forward.      6 Workshop Date Commenter Comment Response  June 23, 2021 Marylin Tiernan, Diablo Water District I am an Oakley citizen on well and have seen water quality degradation over the past 37 years. It has degraded more recently. The community is very built out. We do have seawater intrusion; I see sea lions in the Delta. Also, my neighbors didn’t know about the meeting—who’s responsible for the outreach? Each GSA is responsible for doing outreach which includes a website, flyers, ads in the newspaper, workshops and so on. We can follow up after the meeting with more information. As for your other questions, we will get to them later in the presentation.   June 23, 2021 Bruce Rank Is Discovery Bay running out of water? Our projections show that nobody will run out of water. We understand it’s an important question because they are 100 percent on groundwater, but our projections show that there is no reason for concern. June 23, 2021 Not recorded  Will the raw data be available in one of the draft versions?  Or the final version?  Interested in the sample space (i.e., density of measurement points, and location of the points). A technical appendix will be posted online on the SGMA website: SGMA Documents & Reports — East Contra Costa County Integrated Regional Water Management (eccc‐irwm.org) June 23, 2021 Marylin Tiernan, Diablo Water District What growth (uncontrolled continued building) was considered in this "plan"?  GSP Section 4 looks at the future demands for each GSA. This takes into account projected growth as defined by the general plans. If the projected growth is inconsistent with what we are seeing, it’s something we can reevaluate as needed. The GSAs have the authority to limit growth that is unsustainable. June 23, 2021 Not recorded Would you test water from private wells as we know it’s bad for residents and clearly affecting people? A commercial well is substantially different from a personal well. We are looking at representative wells in the monitoring network to give an overall picture, but we can do private well testing if people are interested.      7 Workshop Date Commenter Comment Response  June 23, 2021 Not recorded  Will Contra Costa County make reuse of graywater mandatory so that landscaping may still be part of a homeowner/property owner experience and can Contra Costa County demand that new subdivisions have these installed?  Landscaping/gardens actually help groundwater retention based on all the reading I have done. Graywater isn’t something that would show up in the model because it’s a small amount of water, but we know that jurisdictions have plans to implement recycled water. Eventually it will get into the ground. There isn’t anything specific in the GSP on this topic. June 23, 2021 Marylin Tiernan, Diablo Water District  How do future land use planning decisions made by government agencies affect future recharge potential? i.e., impermeable surface increases, reduction of native trees, ground cover, construction of flood control channels in new developments. We know that more urban areas have a flashier system (water moves faster), but we are also trying to implement runoff programs in some developments. The groundwater models include land use changes that are part of the city and County general plans such as conversion of agricultural land to urban which would create more runoff and less recharge. GSAs have a responsibility too—if the GSP identifies a recharge area, but the County comes in with a development plan in the same area, GSAs have the responsibility to work with County to say that impacts sustainability.  The County has urban limit line which limits development in unincorporated portion of the County.   June 23, 2021 Not recorded Will the GSP Working Group meeting agendas with teleconference links be posted on the website going forward?  To Diablo Water District has GSA meetings that are open to the public; we would love to have public participation and hope they attend. Discovery Bay and City of Brentwood have done a lot of outreach      8 Workshop Date Commenter Comment Response date, only minutes have been posted after meetings are held. too. The GSP Working Group is about the data and purposefully kept small.  We do want input from the community though so someone can read the minutes and can then participate through the GSA board.   East Contra Costa Subbasin Communications Plan APPENDIX 10c East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan DECEMBER 2018 Prepared for: East Contra Costa Subbasin GSAs Prepared by: Lisa Beutler, Stantec Kirsten Pringle, Stantec This document was developed with technical support provided by the California Department of Water Resources’ (DWR) SGMA Facilitation Support Services Program and completed by the Communication and Engagement Group of Stantec. iii Table of Contents 1.0 INTRODUCTION AND BACKGROUND ........................................................................... 1  1.1 SGMA BASICS ................................................................................................................. 1  1.1.1 GSAs & GSPs ................................................................................................. 1  1.2 SGMA AND THE EAST CONTRA COSTA SUBBASIN .................................................... 2  1.2.1 East Contra Costa Subbasin ........................................................................... 2  1.2.2 Boundary Modification ..................................................................................... 3  1.2.3 East Contra Costa Subbasin GSP Decision Making ....................................... 3  1.2.4 East Contra Costa Subbasin GSAs ................................................................. 3  2.0 SGMA COMMUNICATIONS AND ENGAGEMENT REQUIREMENTS ........................... 4  2.1.1 Beneficial Users ............................................................................................... 7  2.1.2 Mandated Outreach Activities .......................................................................... 8  3.0 COMMUNICATIONS PLAN OVERVIEW ....................................................................... 10  3.1 PURPOSE ....................................................................................................................... 10  3.2 IMPORTANCE ................................................................................................................ 10  3.2.1 Communication Phases ................................................................................. 11  3.3 SCOPE ............................................................................................................................ 12  3.4 COMMUNICATIONS GOALS ......................................................................................... 12  3.5 COMMUNICATIONS OBJECTIVES ............................................................................... 12  3.6 STRATEGIC APPROACH .............................................................................................. 12  3.7 CONSTRAINTS .............................................................................................................. 12  4.0 INITIAL OUTREACH OPPORTUNITIES ........................................................................ 14  4.1 OUTREACH VENUES .................................................................................................... 14  5.0 AUDIENCE AND MESSAGES ....................................................................................... 16  5.1 AUDIENCES ................................................................................................................... 16  5.1.1 Subbasin Stakeholders .................................................................................. 16  5.1.2 Messages Tied to Decision-Making ............................................................... 17  5.2 TAILORING MESSAGES TO AUDIENCES .................................................................... 17  5.2.1 GSA Boards ................................................................................................... 18  5.2.2 Primary Audiences ........................................................................................ 18  5.3 COMMUNICATIONS AND CHANGE MANAGEMENT ................................................... 21  6.0 RISK MANAGEMENT .................................................................................................... 23  6.1 TECHNICAL, QUALITY, OR PERFORMANCE .............................................................. 24  6.2 PROJECT MANAGEMENT ............................................................................................. 24  6.3 ORGANIZATIONAL / INTERNAL .................................................................................... 24  6.4 EXTERNAL ..................................................................................................................... 25  6.5 HISTORICAL ................................................................................................................... 25  7.0 TACTICAL APPROACHES ............................................................................................ 26  7.1 COMMUNICATIONS COORDINATION .......................................................................... 27  iv 7.2 OUTREACH TOOLS ....................................................................................................... 27  7.2.1 Website .......................................................................................................... 28  7.2.2 Social Media Posts .......................................... Error! Bookmark not defined.  7.2.3 Meeting Calendar .......................................................................................... 29  7.2.4 Outreach Materials ........................................................................................ 29  7.2.5 Interested Parties Database .......................................................................... 30  7.2.6 Outreach Venues Database .......................................................................... 31  7.2.7 Outreach Documentation ............................................................................... 31  7.3 OUTREACH TACTICS .................................................................................................... 32  7.3.1 Communications Workbook ........................................................................... 32  7.3.2 Outreach Survey ............................................................................................ 32  7.3.3 GSA Board Meetings and Workshops ........................................................... 32  7.3.4 Public and Stakeholder Workshops ............................................................... 33  7.3.5 Speakers Bureau ........................................................................................... 33  7.3.6 Existing Outreach Venues ............................................................................. 33  7.3.7 Press Releases and Guest Editorials ............................................................ 34  7.4 ITEMS FOR FUTURE CONSIDERATION ...................................................................... 34  8.0 GSP ADOPTION ............................................................................................................. 35  8.1 GSP ADOPTION PROCEEDINGS ................................................................................. 35  8.1.1 Media Relations, Email, and Social Media .................................................... 35  8.1.2 Public Comment Process .............................................................................. 35  8.1.3 Newspaper Advertisements ........................................................................... 36  8.1.4 Public Hearing to Adopt ................................................................................. 36  8.2 POST ADOPTION PROCEEDINGS ............................................................................... 36  9.0 MEASUREMENTS & EVALUATIONS ........................................................................... 37  9.1 PROCESS MEASURES ................................................................................................. 37  9.2 OUTCOME MEASURES ................................................................................................. 37  10.0 COMMUNICATION GOVERNANCE .............................................................................. 38  10.1 ROLES AND RESPONSIBILITIES ................................................................................. 38  10.1.1 Initial Roles .................................................................................................... 39  11.0 LIST OF APPENDICES ............................................................................................... - 1 -  APPENDIX 1. PUBLIC OUTREACH REQUIREMENTS UNDER SGMA .......................... - 3 -  APPENDIX 2. INTERESTED PARTIES DATABASE?? ......................................................... 1  LIST OF TABLES Table 1. Mandated SGMA Outreach Activities ............................................................................. 8  Table 2. Potential Outreach Venues in the East Contra Costa Subbasin ................................... 14  Table 3. Employers* .................................................................................................................... 20  Table 4. Early Phase Message Elements for Subbasin Stakeholders ........................................ 22  Table 5. Risk Factors .................................................................................................................. 23  LIST OF FIGURES v Figure 1. Map of the East Contra Costa Subbasin ....................................................................... 2  Figure 2. Stakeholder Engagement Requirements by SGMA Phase ........................................... 5  Figure 3. Overview of the Communications Plan Elements ........................................................ 10  Figure 4. Communication Phases ............................................................................................... 11  Figure 5. Core Audience Segments ............................................................................................ 16  Figure 6. Communications Planning Questions .......................................................................... 17  Figure 6. Disadvantaged Communities and Economically Disadvantaged Area, ECC Subbasin ...................................................................................................................... 17  Figure 7. IAP2 Public Participation Spectrum ............................................................................. 26  vi Abbreviations Revision History Revision/Section Title # Date of Release Author Summary of Changes Working Draft September 2018 Beutler N/A Final Draft December 2018 Beutler Incorporates Group and Consultant Edits Description Communications Plan East Contra Costa Subbasin, Sustainable Groundwater Management Act, Working Draft Communications Plan DWR California Department of Water Resources GSA Groundwater Sustainability Agency GSP Groundwater Sustainability Plan PDF Portable Document Format SGMA Sustainable Groundwater Management Act State Board State Water Resources Control Board Subbasin East Contra Costa Subbasin 1 1.0 INTRODUCTION AND BACKGROUND The purpose of this Communication Plan is to assist the GSAs of the East Contra Costa Subbasin with stakeholder outreach and other related actions as required by SGMA. Its chapters identify key stakeholders and provide a high- level overview of near and long-term outreach and engagement strategies, tactics, and tools. The content of this Communications Plan was developed, in part, through discussions with GSA representatives at Groundwater Sustainability Plan (GSP) Coordination Group meetings and a survey sent out to GSA representatives. This Communications Plan was created with technical support provided by DWR’s SGMA Facilitation Support Services Program. 1.1 SGMA BASICS1 After decades of debate, California lawmakers adopted SGMA in 2014. This far-reaching law seeks to bring the state’s critically important groundwater basins into a sustainable regime of pumping and recharge. The change in water management laws has created new obligations for residents and water managers in the Subbasin SGMA required, by June 30, 2017, the formation of locally- controlled GSAs in many of the state’s groundwater basins and subbasins. A GSA is responsible for developing and implementing a GSP. These plans assist the basins in meeting sustainability goals. The primary goal is to maintain sustainable yields without causing undesirable results. 1.1.1 GSAs & GSPs Any local public agency that has water supply, water management, or land use responsibilities in a basin can decide to become a GSA. A single local agency can decide to become a GSA, or a combination of local agencies can decide to form a GSA by using either a Joint Power 1 Sections on SGMA are largely drawn, in whole or in part, from publicly available materials from the Department of Water Resources. For more see: http://www.water.ca.gov/groundwater/sgm. 2 Authority, a memorandum of agreement, or other legal agreement. If no agency assumes this role the GSA responsibility defaults to the County; however, the County may decline.  A GSP may be any of the following (California Water Code Section 10727(b)):  A single plan covering the entire basin developed and implemented by one GSA.  A single plan covering the entire basin developed and implemented by multiple GSAs.  Subject to California Water Code Section 10727.6, multiple plans implemented by multiple GSAs and coordinated pursuant to a single coordination agreement that covers the entire basin. If local agencies are unable to form an approved GSA and/or prepare an approved GSP in the required timeframe, then the basin or subbasin would be considered unmanaged. Unmanaged groundwater basins and subbasins are subject to State Water Resources Control Board oversight. This is true even if the vast majority of the subbasin is covered by a plan. Should intervention occur, the State Water Resources Control Board is authorized to recover its costs from the GSAs. 1.2 SGMA AND THE EAST CONTRA COSTA SUBBASIN 1.2.1 East Contra Costa Subbasin The East Contra Costa Subbasin (DWR Bulletin 118, 5-22.15) (Figure 1) is a medium-priority subbasin within the larger San Joaquin Valley Groundwater Basin. The Subbasin covers the eastern portion of Contra Costa County. The northern boundary (from west to east) of the Subbasin follows the San Joaquin River west until its convergence with the Mokelumne River by Webb Tract. The eastern boundary (from north to south) follows the Old River south until the Contra Cost-San Joaquin-Alameda County intersection. The southern boundary (from east to west) continues to follow the Contra Costa-Alameda County line. The western boundary (from south to north) follows the Diablo Range north up to the section of the San Joaquin River near the City of Antioch. Adjacent subbasins include the Tracy Subbasin on the east and south, which is also part of the larger San Joaquin Valley Groundwater Basin; as well as the Solano Subbasin of the Sacramento Groundwater Basin to the north. Figure 1. Map of the East Contra Costa Subbasin 3 The East Contra Costa Subbasin is drained by the San Joaquin River and west side tributaries; Marsh Creek. The San Joaquin River flows northward into the Sacramento and San Joaquin Delta and discharges into the San Francisco Bay. 1.2.2 Boundary Modification Agencies of the Tracy Subbasin submitted a Basin Boundary Modification Request (BBMR) to DWR in September 2018. In order to better facilitate jurisdictional issues, they requested separation of the Tracy Subbasin into two subbasins along the Old River to form the East Contra Costa and Tracy Subbasins. DWR announced a draft decision to approve the basin boundary modification requests (BBMR) in November 2018. Therefore, the new East Contra Costa Subbasin is the subject of this Plan. 1.2.3 East Contra Costa Subbasin GSP Decision Making The GSAs in the Subbasin intend to work together to meet SGMA requirements and collaboratively prepare a single GSP by January 31, 2022. The GSAs currently meet in regular coordination meetings to discuss GSP development and public outreach and engagement activities. This GSP Coordination Group is comprised of representatives from each GSA within the Subbasin and follows a consensus-based decision-making structure, where each GSA representative receives an equal vote. This Communications Plan is offered for the voluntary use of all the GSAs in the Subbasin. A full schedule including calendared outreach timeframes is provided in Appendix A. should be developed in conjunction with the overall GSP development schedule. An important additional step will be establishing the roles and responsibilities outlined in Section 10 of this Communications Plan. 1.2.4 East Contra Costa Subbasin GSAs Following are the DWR identified GSAs (as of December, 2018):  Byron-Bethany Irrigation District  City of Antioch  City of Brentwood  Contra Costa County  Diablo Water District  Discovery Bay Community Services District  East Contra Costa Irrigation District 4 2.0 SGMA COMMUNICATIONS AND ENGAGEMENT REQUIREMENTS SGMA includes specific requirements for communications and engagement by each planning phase. Figure 2 (next page) illustrates the requirements and provides water code references. The GSP submittal guidelines also describe the outreach and engagement documentation to be submitted with the plan. California Code of Regulations Section 354.10 states that each Plan shall include a summary of information relating to notification and communication by the Agency with other agencies and interested parties including the following: (a) A description of the beneficial uses and users of groundwater in the basin, including the land uses and property interests potentially affected by the use of groundwater in the basin, the types of parties representing those interests, and the nature of consultation with those parties. (b) A list of public meetings at which the Plan was discussed or considered by the Agency. (c) Comments regarding the Plan received by the Agency and a summary of any responses by the Agency. (d) A communication section of the Plan that includes the following: (1) An explanation of the Agency’s decision-making process. (2) Identification of opportunities for public engagement and a discussion of how public input and response will be used. (3) A description of how the Agency encourages the active involvement of diverse social, cultural and economic elements of the population within the basin. (4) The method the Agency shall follow to inform the public about progress implementing the Plan, including the status of projects and actions. A full list of codes and requirements is also provided in Appendix B. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 5 Figure 2. Stakeholder Engagement Requirements by SGMA Phase East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 7 2.1.1 Beneficial Users Pursuant to Section 10723.2 of the California Water Code, each GSA must consider the interests of all beneficial users and users of groundwater within the Subbasin, as well as those responsible for implementing GSPs. Following are the Required Interested Parties for the purpose of mandated outreach:  Holders of overlying groundwater rights, including:  Agricultural users.  Domestic well owners.  Municipal well operators.  Public water systems.  Local land use planning agencies.  Environmental users of groundwater.  Surface water users, if there is a hydrologic connection between surface and groundwater bodies.  The federal government, including, but not limited to, the military and managers of federal lands.  California Native American tribes.  Disadvantaged communities, including, but not limited to, those served by private domestic wells or small community water systems.  Entities listed in Section 109272 that are monitoring and reporting groundwater elevations in all or a part of a groundwater basin managed by the groundwater sustainability agency. 2 CA Water Code § 10927 (2017) Any of the following entities may assume responsibility for monitoring and reporting groundwater elevations in all or a part of a basin or subbasin in accordance with this part: (a) A watermaster or water management engineer appointed by a court or pursuant to statute to administer a final judgment determining rights to groundwater. (b) (1) A groundwater management agency with statutory authority to manage groundwater pursuant to its principal act that is monitoring groundwater elevations in all or a part of a groundwater basin or subbasin on or before January 1, 2010. (2) A water replenishment district established pursuant to Division 18 (commencing with Section 60000). This part does not expand or otherwise affect the authority of a water replenishment district relating to monitoring groundwater elevations. (3) A groundwater sustainability agency with statutory authority to manage groundwater pursuant to Part 2.74 (commencing with Section 10720). (c) A local agency that is managing all or part of a groundwater basin or subbasin pursuant to Part 2.75 (commencing with Section 10750) and that was monitoring groundwater elevations in all or a part of a groundwater basin or subbasin on or before January 1, 2010, or a local agency or county that is managing all or part of a groundwater basin or subbasin pursuant to any other legally enforceable groundwater East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 8 2.1.2 Mandated Outreach Activities Table 1 provides a list of the mandated outreach and the timeframe in which is required. Table 1. Mandated SGMA Outreach Activities Timeframe Item Prior to initiating plan development  Statement of how interested parties may contact the Agency and participate in development and implementation of the plan submitted to DWR.  Web posting of same information. Prior to plan development  Must establish and maintain an interested persons list.  Must prepare a written statement describing the manner in which interested parties may participate in GSP development and implementation. Statement must be provided to:  Legislative body of any city and/or county within the geographic area of the plan  Public Utilities Commission if the geographic area includes a regulated public water system regulated by that Commission  DWR  Interested parties (see Section 10927)  The public Prior to and with GSP submission  Statements of issues and interests of beneficial users of basin groundwater, including types of parties representing the interests and consultation process  Lists of public meetings  Inventory of comments and summary of responses  Communication section in plan that includes:  Agency decision making process  Identification of public engagement opportunities and response process  Description of process for inclusion management plan with provisions that are substantively similar to those described in that part and that was monitoring groundwater elevations in all or a part of a groundwater basin or subbasin on or before January 1, 2010. (d) A local agency that is managing all or part of a groundwater basin or subbasin pursuant to an integrated regional water management plan prepared pursuant to Part 2.2 (commencing with Section 10530) that includes a groundwater management component that complies with the requirements of Section 10753.7. (e) A local agency that has been collecting and reporting groundwater elevations and that does not have an adopted groundwater management plan, if the local agency adopts a groundwater management plan in accordance with Part 2.75 (commencing with Section 10750) by January 1, 2014. The department may authorize the local agency to conduct the monitoring and reporting of groundwater elevations pursuant to this part on an interim basis, until the local agency adopts a groundwater management plan in accordance with Part 2.75 (commencing with Section 10750) or until January 1, 2014, whichever occurs first. (f) A county that is not managing all or a part of a groundwater basin or subbasin pursuant to a legally enforceable groundwater management plan with provisions that are substantively similar to those described in Part 2.75 (commencing with Section 10750). (g) A voluntary cooperative groundwater monitoring association formed pursuant to Section 10935. (Amended by Stats. 2014, Ch. 346, Sec. 5. (SB 1168) Effective January 1, 2015.) East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 9 Timeframe Item  Method for public information related to progress in implementing the plan (status, projects, actions) 90 days prior to GSP Adoption Hearing Prior to Public Hearing for adoption or amendment of the GSP, the GSP entities must notify cities and/or counties of geographic area 90 days in advance. 90 days or less prior to GSP Adoption Hearing  Prior to Public Hearing for adoption or amendment of the GSP, the GSP entities must:  Consider and review comments  Conduct consultation within 30 days of receipt with cities or counties so requesting GSP Adoption or Amendment GSP must be adopted or amended after a Public Hearing. 60 days after plan submission 60-day comment period for plans under submission to DWR. Comments will be used to evaluate the submission. Prior to adoption of fees  Public meeting required prior to adoption of, or increase to fees. Oral or written presentations may be made as part of the meeting.  Public notice shall include:  Time and place of meeting  General explanation of matter to be considered  Statement of availability for data required to initiate or amend such fees  Public posting on Agency Website and provision by mail to interested parties of supporting data (at least 20 days in advance)  Mailing lists for interested parties are valid for 1 year from date of request and may be renewed by written request of the parties on or before April 1 of each year.  Includes procedural requirements per Government Code, Section 6066. Prior to conducting a fee adoption hearing. Must publish notices in a newspaper of general circulation as prescribed. Publication shall be once a week for two successive weeks. Two publications in a newspaper published once a week or oftener, with at least five days intervening between the respective publication dates not counting such publication dates, are sufficient. The period of notice begins the first day of publication and terminates at the end of the fourteenth day, (which includes the first day.) East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 10 3.0 COMMUNICATIONS PLAN OVERVIEW Communication is the process of transmitting ideas and information. According to the Project Management Institute, 75%-90% of a project manager’s time is spent communicating. A Communications Plan provides the purpose, method, messages, timing, intensity, and audience of the communication, then describes who will do the communicating, and the frequency of the communication (see Figure 3.) Figure 3. Overview of the Communications Plan Elements 3.1 PURPOSE The purpose of this Communications Plan is to outline the information and communications needs of stakeholders within the Subbasin and provide a roadmap to meet them. This Communications Plan then identifies how communications activities, processes, and procedures will be managed throughout the project life cycle. 3.2 IMPORTANCE While communications are important in every project, a well-executed communications strategy will be essential to the success of the GSP development and adoption process. The financial and regulatory stakes are high and communication missteps can create project risks. Further, development of a viable GSP will require an on-going collaboration among all the stakeholders, Degrees  Level of Engagement Topics/Messages  Project phase/ Goals/Venues & audience Timing  Project phase/ Goals/Venues & audience Audience  Leverage existing audiences  Multiple audiences Methods/Venues East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 11 both organizational and external. The plan will be comprehensive and consider multiple variables, a range of system elements and project costs and benefits. Stakeholder input will be needed to refine GSP requirements and fully define the water management system, and potential impacts, costs and benefits that may result in managing for sustainability. 3.2.1 Communication Phases Communications are unique for each GSP development phase. Following are Phases where communication messages will be needed. Figure 4. Communication Phases For each Communications Phase, the GSAs also need to determine: 1. Level of Engagement (Degrees) – How much outreach is needed? 2. Topics, Messages – What do people need to know? 3. Timing – When should this occur? Phase I •GSA  Formation •GSP  Organization Phase IIA •GSP  Development Phase IIB •GSP  Coordination  with  Adjacent  Subbasins Phase III •GSP  Adoption Phase  IV •GSP Implementation East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 12 4. Audience – Who are the right people to talk with? 5. Methods/Venues – What is the best method to reach them? 3.3 SCOPE This Communications Plan focuses on formal communication elements. Other communication channels exist on informal levels and enhance those discussed within this plan. This plan is not intended to limit, but to enhance communication practices. Open, ongoing communication between stakeholders is critical to the success of the project. 3.4 COMMUNICATIONS GOALS Development, adoption and implementation of the GSP will require basin external stakeholders, other agencies, staff, managers, and the multiple GSA Boards to evaluate choices, make decisions, and commit resources. The core communications goal is to plan for and efficiently deliver clear and succinct information: (1) at the right time, (2) to the right people, (3) with a resonating message. This is done to facilitate quality decision making and build accompanying public support 3.5 COMMUNICATIONS OBJECTIVES The objectives of this Communications Plan are to present strategies and actions that are:  Realistic and action-oriented  Specific and measurable  Minimal in number (a few well delivered are better than many mediocre efforts)  Audience relevant 3.6 STRATEGIC APPROACH Three primary communications strategies have been identified for the GSP development. 6. Fully leverage the activities of existing groups. This practical approach is cost effective and respectful of the limited time that stakeholders have to participate in collaborative processes. 7. Provide targeted, communications and outreach to opinion leaders in key stakeholder segments. 8. Provide user friendly information and intermittent opportunities through existing communication channels, surveys, and open houses or workshops to allow interested stakeholders (internal and external) to engage commensurate with their degree of interest. 3.7 CONSTRAINTS All projects are subject to limitations and constraints as they must be within scope and adhere to budget, scheduling, and resource requirements. These constraints can be even more challenging in projects with multiple agencies as will be the case with the coordination of East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 13 multiple GSAs. There are also legislative, regulatory, technology, and other organizational policy requirements which must be followed as part of communications management. These limitations must be clearly understood and communicated where appropriate. While communications management is arguably one of the most important aspects of project management, it must be done in an effective and strategic manner recognizing and balancing the multiple constraints. All project communication activities should occur within the project’s approved budget, schedule, and resource allocations. The GSP project managers and the leadership of the participating GSAs should have identified roles in ensuring that communication activities are performed. To the extent possible, to support collaboration and reduce costs, GSA partners should utilize standardized formats and templates as well as project file management and collaboration tools. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 14 4.0 INITIAL OUTREACH OPPORTUNITIES As part of development of this Communications Plan, a neutral, 3rd party facilitator conducted a survey with GSA representatives to collect information on outreach opportunities in the Subbasin. In addition, the facilitator conducted a series of discussions with GSA representatives at GSP Coordination Group meetings. The purpose of these activities was to inform development of this Communications Plan, as well as develop an initial list of outreach opportunities in the Subbasin. The outreach opportunities survey asked GSA representatives to identify potential outreach venues within the Subbasin. The survey was provided in an electronic format to GSA representatives in the Subbasin. Seven GSAs completed the survey. The results of the survey and other discussions with GSA representatives are summarized below. 4.1 OUTREACH VENUES GSA representatives have identified a list of potential outreach venues in the Subbasin, shown in Table 2 below. Note that this is only an initial list of outreach venues. The GSAs will continue to expand this list and develop a full Outreach Venues Database, described in Subsection 7.2.7. Table 2. Potential Outreach Venues in the East Contra Costa Subbasin Organization/Event Name Type of Organization/Event Location Contra Costa County Farm Bureau Agricultural Contra Costa County Brentwood Lions Club Civic/Community Brentwood Discovery Bay Chamber of Commerce Commercial Discovery Bay Oakley Chamber of Commerce Commercial Oakley Discovery Bay Lions Club Civic/Community Discovery Bay Earth Day Event Multiple locations throughout Subbasin Brentwood City Council Government/Municipal Brentwood Brentwood Planning Commission Government/Municipal Brentwood Contra Costa County Board of Supervisors Government/Municipal Contra Costa County Contra Costa County Municipal Advisory Council – Byron and Bethel Island Government/Municipal Contra Costa County Contra Costa County Municipal Advisory Council - Knightsen Government/Municipal Contra Costa County Contra Costa County Transportation, Water, Infrastructure Committee Government/Municipal Contra Costa County Oakley City Council Government/Municipal Oakley East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 15 Building Industrial Association - East Bay Chapter Industrial Contra Costa County Industrial Association of Contra Costa County Industrial Contra Costa County Farmers Market Other Brentwood East County Water Management Association Board Meeting Other Contra Costa County Realtor groups Other Multiple locations throughout Subbasin East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 16 5.0 AUDIENCE AND MESSAGES 5.1 AUDIENCES This Communications Plan anticipates two core audience segments. First is the East Contra Costa Subbasin GSA Boards and the communications among and between themselves. This audience segment is large given that seven GSAs will be working to develop a GSP and each GSA has its own Board and audiences. The second audience is the Subbasin stakeholders, as identified in SGMA. This audience is also large. Many of the stakeholders are shared by the GSA Boards and some of the larger stakeholder segments are also represented on the GSA Boards (see Figure 4). Nearly all of the communications tactics identified in this Communications Plan apply to both segments; however, some strategies apply to one or the other specifically and are so identified. 5.1.1 Subbasin Stakeholders Pursuant to Section 10723.2 of the California Water Code, each GSA must consider the interests of all beneficial users and users of groundwater within the Subbasin, as well as those responsible for implementing GSPs. These interests include the following:  Agricultural users, including farmers, ranchers, and dairy professionals.  Domestic well owners.  Municipal well operators.  Public water systems.  Local land use planning agencies.  Environmental users of groundwater.  Surface water users, if there is a hydrologic connection between surface and groundwater bodies.  The federal government, including, but not limited to, the military and managers of federal lands.  California Native American tribes.  Disadvantaged communities, including, but not limited to, those served by private domestic wells or small community water systems.  Entities monitoring or reporting groundwater elevations in the subbasin As part of the GSA formation process, each GSA was required to provide a list of interested parties developed pursuant to California Water Code Section 10723.2, and explain how these interested parties would be considered in the development and operation of the GSA and development and implementation of the GSP. This list has been augmented by the facilitation and technical teams with input from the GSAs. GSAs should periodically assess their list of beneficial users and develop tactics or activities to refine the list, identify and fill any gaps. GSA  Boards Subbasin Stakeholders Figure 5. Core Audience Segments East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 17 The County of Contra Costa, supported by the Diablo Water District, has established and maintained a mailing list and Interested Parties Database (Appendix B or 2?). 5.1.2 Messages Tied to Decision-Making Communications will be linked to decision making. For each anticipated decision, GSAs should answer the following questions: 1. Who is the stakeholder? a) An impacted party? b) A potential planning partner? c) A potential provider of services or resources? d) A regulator of the activity? (Note: Some stakeholders may be in more than one category.) 2. What is the interest of the stakeholder? How will the stakeholder be affected? What are the stakeholders’ needs? 3. Who is the right messenger for the information? 4. How should the information be delivered? What are the best methods? 5. What is the appropriate timing for the messages? 6. How do we create two-way communication? Figure 6 illustrates some of these ideas. Figure 6. Communications Planning Questions 5.2 TAILORING MESSAGES TO AUDIENCES There are several core stakeholder groups that will require ongoing communications and tailored messaging throughout the planning process. They are:  GSA Boards  Agriculture  Disadvantaged Communities  Municipalities Other stakeholders requiring special consideration include: East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 18  Industrial Users/ Business  Regulators (State and Federal)  Potential Partners  Environmental Organizations  Federal Agencies While all of the stakeholder types are important to engage for development of a GSP, the core stakeholder groups will be most affected by any changes that might be proposed as a result of the GSP(s). 5.2.1 GSA Boards Due to the multiple GSAs in the Subbasin, specific focus is needed on communications to keep them informed, provide consistent updates and information that the Boards can use in their own outreach, and support their decision making. Primary objectives for communications with the GSA Boards are to ensure:  Consistent understanding of the requirements for a GSP and/or GSP coordination  On-going access to current information  Timely notice of any significant developments or decision points that may require changes to policies and/or require some other board action  Confidence that the GSP will be accepted by the GSA’s stakeholders Key communications activities involving the Board include: 1. Providing short and digestible pieces of information to ensure each Board member can quickly articulate to his/her constituents on key matters and remain sufficiently informed so that no decision points are surprises. 2. Provide user-friendly informational materials to be used with public audiences, and will support the Board with their own constituent outreach. 3. Utilize regular Board communications for routine updates and reserve specific Board agenda items for highly significant discussion items. The GSAs have agreed to: 1. Share standardized information that can be used by managers and executives with all of their Boards. 2. Utilize Managers Reports and standing items in Board agendas. 5.2.2 Primary Audiences The following provides an outline of key messages and activities in support of each of the audience types. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 19 5.2.2.1 Agricultural The East Contra Costa Subbasin includes a significant portion of the County’s agriculture footprint. A 2013 report on the Economic Contributions of Contra Costa County Agriculture indicates county-wide agriculture contributes a total of $225.0 million to the local economy, and provides 2,277 jobs in Contra Costa County economy. It was found to have exceptional diversity that provides critical economic stability within agriculture and the broader economy. Humberto Izquierdo, the Contra Costa Agricultural Commissioner, in the annual crop report reported the total gross value of County agricultural crops in 2017 was $120,441,000 which was a decrease of $7,615,000 or 6% from 2016. The report indicates that “in general, demand and prices have remained strong for agricultural crops in Contra Costa County. Crop values vary from year to year due to factors such as production, weather, and market conditions. Some notable changes include an 31% increase in nursery product value and a significant decrease of 43% of field crop values. Approximately 2.5% or 4,861 acres of the total cultivated acreage was farmed organically on 15 farms. Several crop categories exceeded one million dollars in value. These categories in decreasing order include cattle and calves, tomatoes, sweet corn, grapes, miscellaneous vegetables, cherries, rangeland, walnuts, irrigated pasture, field corn, peaches and alfalfa hay. The economic benefit of agricultural production is generally thought to be about three times the gross production value.” GSAs should monitor any agricultural trends within their jurisdiction and make adjustments to tailor messages appropriate to the audience. Messages about the GSP development should feature the overall desirability of a sustainable management approach and describe how the plan will contribute to management certainty and protect against regulatory oversight. In thinking about irrigation users it is also important to remember that one size does not fit all. Where possible, GSAs should leverage existing outreach channels for reaching agricultural stakeholders, such as local Farm Bureaus and the County Agricultural Commissioner. This will be all the more important given the diversity of crop types. 5.2.2.2 Disadvantaged Communities Messages developed for this sector should be tailored and specific to the community. This type of outreach is often best served by use of surrogates and trusted messengers. These messages should be aligned with activities of the Integrated Regional Water Management (IRWM) Plan. Messages about ways to access the increased availability of resources due to grant incentives should also be considered. ECC Subbasin Disadvantaged Communities and Economically Disadvantaged Areas are illustrated in Figure 7. Figure 7. Disadvantaged Communities and Economically Disadvantaged Area, ECC Subbasin. 5.2.2.3 Municipalities Some care will be needed to address any tensions that may arise as GSP implementation actions are developed. Concerns may relate to the relative percentages of use by municipal agencies and the determination of what constitutes the highest and best beneficial uses within the region. A promising interaction with this community would involve collaboration on messaging with the IRWM planning process to achieve mutually beneficial goals. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 20 Municipal agencies have been providing in-kind support to the GSP development process through support for project websites and mailing lists, production of meeting notices, assistance to the planning process from in-house public information professionals, and offering access to physical meeting spaces. Municipalities not already engaged may need assistance in making the case for the need to think at a basin or subbasin scale rather than more local terms. 5.2.2.4 Business and Industry Interests Business and industry interests seek assurances about the availability of water for operations. Following (Table 3) are the top employers in unincorporated Contra Costa County, unlike agriculture, many of the larger employers are outside of the East Contra Costa Subbasin but the employees may live in the subbasin. Table 3. Employers* *Source: America’s Labor Market Information System Database, downloaded via State of California Employment Development Department, March 1, 2018 & County of Contra Costa. Rather than the listed major employers, the primary business interests for this GSP is likely to be the realtor and building industries. Outreach should focus on professional associations. Messages for these audiences should focus on how the GSP development will contribute to sustainability and how these audiences can participate in discussions specific to their interests. 5.2.2.5 Regional/Statewide Interests and Regulators Some degree of uncertainty remains in the overall legal, legislative and regulatory environment as it relates to SGMA implementation. It is in the interest of the Subbasin stakeholders to engage state and federal agencies and regulators throughout the process. These parties may East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 21 have resources to assist the subbasin and a cooperative attitude will build good will in the event that adjustments are needed to achieve SGMA compliance. 5.2.2.6 Potential Agency Partners A variety of collaborations to achieve GSP development goals may be possible. The GSAs should consider the potential for collaboration with non-GSA members and inter/intra-basin (adjacent subbasin(s)) partners, as part of plan deliberations. 5.2.2.7 Environmental Community The focus of messaging for this group being on how the GSP development will contribute to a sustainable regional water portfolio which includes surface water sustainability. Special effort should be made to identify specific topics of interest. For example, as part of GSP development, a list of groundwater dependent species may be created, or impacts to wetlands may be identified. These types of lists would highlight where input from the environmental community might be needed. 5.2.2.8 Federal Government Federal representatives interviewed for the assessment asked to be kept informed of subbasin SGMA activities. These agencies have a direct interest in surface water integration as well as SGMA activities that could impact wetlands restoration efforts or groundwater dependent ecosystems and species. 5.3 COMMUNICATIONS AND CHANGE MANAGEMENT The process of adopting and implementing a GSP will require significant change management. Communications planning should encompass basic change management approaches. Messages should also evolve over time and be tied to the planning process and key decision points. Then, for each audience and each major planning step, communications must do the following: 3. Describe what the actual proposed plan (change) is. 4. Articulate how the change will directly impact the category of stakeholder involved. 5. Outline the methods that will be used to implement the plan (change). 6. Define the costs and benefits of changing and not changing, and what future conditions will be if change does not occur. 7. Consider unintended consequences and others that may also be impacted by the same change then develop a strategy to engage them. 8. Offer opportunities for input and for stakeholders and others to improve the approach. The communications requirements for large changes are often underestimated. Some experts indicate that messages may need to be delivered up to 8 different times to be fully absorbed. Communications needs will also evolve as the GSP planning progresses. Table 4 on the following page provides a sample of early communications that focus on SGMA and groundwater basics. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 22 As part of the GSP planning process, the next phase of communications will also need to communicate the requirements for sustainability and how they are achieved in the context of the Subbasin. Once the GSP begins to be formulated and again as projects are proposed, a message tables, similar to Table 4 and should be developed for each major project phase (see Chapter 3). For the purposes of the GSP required Communication plan these primary messages should be documented and shared with the GSAs for use in developing GSA communications. Table 4. Early Phase Message Elements for Subbasin Stakeholders Element What the Change Is How it will affect the Stakeholder How the change will be Implemented Why it is a good idea Early Phase GSP Development Locally governed GSAs will work together to sustainably manage ground water. The Subbasin /Basin is required to ensure Sustainable Groundwater Management by submitting a sustainability plan by 2022 The plan must be implemented and found to result in sustainable management by 2042. (Unique to audience type) Changes in the current methods of acquiring and utilizing groundwater may occur. May affect future decisions related to crop types and decisions related to conjunctively using surface water. May provide additional project resources to the DAC communities. A collaborative approach is being undertaken to prepare the plan with multiple GSAs coordinating with the __________ (NAME) as the planning organizer. Sustainable and wise use of groundwater allows for the success of future generations and creates greater certainty for today’s beneficial users. Failure to act may result in negative regulatory consequences. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan DEC 2018 23 6.0 RISK MANAGEMENT Risk management is the identification, assessment, and prioritization of risks (defined as the effect of uncertainty on achieving objectives) followed by coordinated, efficient and economical strategies and actions to minimize, monitor, and control the probability and/or impact of negative events. Strategies and actions may also be used to avert risk by leveraging strengths and opportunities. Risks can come from uncertainty in economic factors, threats from project failures (at any phase), regulatory and legal uncertainties, natural causes and disasters (drought, flood, etc.), as well as dissention from adversaries, or events of uncertain or unpredictable circumstances. Several risk management standards have been developed. This analysis utilizes those from the Project Management Institute. Table 5 outlines standardized risk categories and translates them to outreach risks. Table 5. Risk Factors Risk Category Outreach Risk Factors Technical, quality, or performance  Realistic performance goals, scope and objectives Project management  Quality of outreach design  Outreach deployment and change management  Appropriate allocation of time and resources  Adequate support for outreach in project management plans Organizational / Internal  Executive Sponsorship  Proper prioritization of efforts  Conflicts with other functions  Distribution of workload between organizational and consultant teams External  Legal and regulatory environment  Changing priorities  Risks related to political dynamics Historical  Past experiences with similar projects  Organizational relations with stakeholders  Policy and data adequacy  Media and stakeholder fatigue East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan DEC 2018 24 6.1 TECHNICAL, QUALITY, OR PERFORMANCE GSAs in the Subbasin are expected to meet the SGMA requirements related to GSP development. However, a potential concern in this category is fulfilling SGMA requirements for stakeholder outreach and engagement. GSA representatives have previously expressed concern about the degree of engagement that may be expected from their boards. In addition, some GSA representatives may be unfamiliar or inexperienced with conducting outreach, especially on a subbasin-wide scale. Outreach requirements should be an ongoing consideration and currently appears to be underestimated in emphasis at both the Subbasin- and GSA-level. Additional organizational capacity and resources may be required to ensure that stakeholders within the Subbasin are kept informed of GSP development activities and are provided meaningful opportunities to engage in the GSP development process. GSAs should collaborate and work closely with their consultants to identify stakeholders, refine their Interested Parties Databases, conduct a variety of outreach tactics, and maintain documentation of all outreach activities. 6.2 PROJECT MANAGEMENT Project management is currently being delegated to a technical consultant, with oversight from the GSP Coordination Group. The primary concern in this category relates to ensuring that the consultant’s scope and budget meets all the necessary requirements to achieve both technical and outreach goals. The GSP Coordination Group should make sure that adequate resources are being allocated to outreach activities. This includes both the consultant’s time and support, as well as GSA staff time and resources to guide the consultant team. GSAs should evaluate the current resources available for GSP development and outreach activities and consider if additional support is required. Some outreach tools and tactics also require a high level of participation from GSA staff. GSAs should identify where GSA-level resources are most required and plan accordingly. 6.3 ORGANIZATIONAL / INTERNAL One concern in this category is potential competition for resources with other programs or projects. GSA representatives often work on multiple projects or serve other roles within their agency. Staff time or resources may be re-allocated to other projects or programs. Small agencies or water districts also contend with existing constraints on resources. GSA representatives should ensure that organizational resources for SGMA are balanced with other programs. GSAs should also take advantage of funding and technical support services offered through DWR and other state agencies to augment local resources. Another concern in this category is the distribution of workload between the GSA and consultant teams. Clear roles and responsibilities must be defined and continuous interactions in place to ensure successful execution. High-level spokespersons or champions within the GSAs should be identified during the GSP development process. These individuals should be able to discuss Subbasin planning with the media, regulators, or stakeholders, with support from the technical consultant. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan DEC 2018 25 6.4 EXTERNAL The legal and regulatory environment of the GSP development process is complex and evolving. Ongoing issues with surface water deliveries and changing market conditions are outside of the control of the parties. It will be important for mechanisms to be in place that allow for relatively rapid responses to changing conditions. 6.5 HISTORICAL Agencies in the Subbasin have a long and successful history working together to manage water, especially regarding issues related to the Integrated Regional Water Management. Therefore, historical risk factors are considered to be low. One concern in this category may be stakeholder fatigue. Where possible, GSAs should try to leverage existing outreach efforts and communications channels. For example, GSA should attempt to leverage disadvantaged communities outreach activities being conducted as part of the Integrated Regional Water Management program. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 26 7.0 TACTICAL APPROACHES This section describes specific tactical tools and approaches to deliver the activities, messages, and recommendations of the previous chapters. These approaches are based on best communication practices and grounded in the public participation philosophy of the International Association for Public Participation, Public Participation Spectrum as illustrated in Figure 8. The Spectrum represents a philosophy that outreach should match the desired level of input from both the stakeholder and the organizational entity. Figure 8. IAP2 Public Participation Spectrum The level of engagement should be adapted to the type and needs of the stakeholder, as well as the stakeholder’s interest in and nexus to SGMA. Many stakeholders simply seek to be informed, unless there is a potential for significant changes that may include them. Tactics and tools for this group may include fact sheets, website, open houses, briefings to community East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 27 groups such as the Chamber of Commerce or Rotary, and informational items placed in publications they already read. Other stakeholders, such as groundwater pumpers or disadvantaged communities, may seek to be consulted. This group should have access to all the outreach materials, as well be invited to provide comments or written materials and planning concepts. These stakeholders may also participate in focused workshops and/or briefings and should be invited to attend larger public meetings. The development of some GSP features may also require a higher degree of involvement. This would focus on engagement of a subset of stakeholders that may experience significant impacts associated with SGMA. Collaboration opportunities are of a different character than defined in the Spectrum. Collaboration in this GSP development process will focus on working with partners that have mutual goals to achieve those goals together. This will more resemble a partnership than a public engagement activity. 7.1 COMMUNICATIONS COORDINATION Each GSA is required to perform legally mandated outreach activities and the GSP submission guidelines require a minimum level of engagement. The GSAs in the Subbasin should coordinate outreach activities. In addition to efficiency and cost savings (the GSAs can share resources), coordinated communications will allow for consistency in messaging and reduce confusion for stakeholders that may not know what GSA jurisdiction they are in, and/or are in multiple GSA jurisdictions. The following are suggested tools and tactics for communications coordination:  Website  Meeting calendar  Branded informational Flyers, Templates, PowerPoint Presentations, etc.  Periodic newsletter  GSP related mailing lists  Descriptions of interested parties  Issues and interest statements for legally mandatory interested parties  Public workshops  Press releases and guest editorials  Speakers Bureau  Existing group venues  Outreach documentation  Some of these tools and tactics are further described in Sections 7.2 and 7.3. 7.2 OUTREACH TOOLS Outreach tools are used to identify, track engagement with, and disseminate information to stakeholders. This section describes a suite of tools that could be utilized by GSAs in the Subbasin to conduct SGMA outreach activities. GSAs should provide materials in multiple languages. A minimum, outreach materials should be available in Spanish. In 2015, the most East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 28 common non-English language spoken in Contra Costa County, CA was Spanish. 16% of the overall population of Contra Costa County, CA are native Spanish speakers while 2.88% speak Chinese and 2.84% speak Tagalog, the next two most common languages. A common visual identity or branding should be implemented for all printed and electronic informational materials intended for public and stakeholder audiences. 7.2.1 Website An internet website(s) has been established and is utilized to provide background information and context; promote public engagement activities; and develop an Interested Parties Database. In addition, Section 10725.2(b) of the California Water Code states that each GSA must “provide notice of the proposed adoption of the groundwater sustainability plan on its Internet Web site and provide for electronic notice to any person who requests electronic notification.” A website for the ECC Subbasin has been developed by Contra Costa Water District (https://www.eccc-irwm.org/sgma/sgma-news-meetings/). This website will serve as the centralized location for SGMA information within the Subbasin. The GSAs should develop a procedure for maintaining, updating, and sharing the costs associated with the centralized websites. Central points of contact for information about the individual GSAs and the GSP process should be identified on the website. Related to the GSP process the group could designate on knowledgeable individual that could route any requests for information as appropriate. Those GSAs with their own SGMA webpages link to and from the centralized SGMA websites and some provide their own customized information. For those GSAs without their own website, courtesy pages will be provided as an added feature of the central sites. The courtesy pages will all use a single template with the same information to facilitate easy management and updates. Individual GSAs choosing to take advantage of the courtesy pages will be responsible for ensuring that information is current. The page should include a “Last Updated” box to indicate the timeliness of the information. Basic features of the website should include the following:  Background information, including map of the Subbasin  Information on how stakeholders or interested members of the public can get involved  Method to enroll on the Interested Parties Database  Public meeting notices and summaries  Informational materials, including a separate link for Spanish (or other secondary language) materials  Frequently asked questions  Links to GSA webpages  Contact information (name, email, phone) for each GSA point of contact Should a GSA decide to not participate in the central website, a similar website structure could be utilized for the individual GSA. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 29 7.2.2 Meeting Calendar A shared meeting calendar on the GSP website will provide a one-stop shop for stakeholders and assist in preventing meeting conflicts while creating more potential for shared activities. This calendar should include current and scheduled meetings and workshops, as well as serve as the repository for agendas and meeting summaries, along with copies of meeting materials and presentation slides. An integrated project calendar should also be developed that links planning project milestones with communications milestones. The meeting calendar should be incorporated as part of the centralized GSA websites. 7.2.3 Outreach Materials The GSAs should collaboratively develop a suite of Subbasin-level outreach materials. These outreach materials should have a single look and feel to create ongoing consistency and visual recognition by stakeholders. Template materials may be refined or modified by individual GSAs to be fit-for-purpose or incorporate specific GSA-level information, while maintaining the key messages. The use of templates, shared presentations, and flyers will create efficiencies and reinforce messaging across the Subbasin. Outreach materials should evolve over time as the GSP is completed, adopted, and implemented. Potential outreach materials are futher described below. 7.2.3.1 Brochures and Fact Sheets The purpose of these types of documents is to inform the public and stakeholders about a specific issue. Information in these materials should be kept at a high-level and avoid technical jargon, unless defined in the material itself. The materials should also include the address for the Subbasin website(s) and GSA or GSP contact information. The materials can be formatted or printed by each GSA, as needed. Template brochures or fact sheets may be developed to address Subbasin-level issues and incorporate key messages. 7.2.3.2 Presentation Slides Template presentation slides provide visual and text content to verbal presentations. The presentation slides should utilize the key messages and answer basic questions about SGMA and the Subbasin, including:  What is SGMA?  What and when are the major SGMA milestones?  What is a GSA?  Who/where are the GSAs in the Subbasin?  What is a GSP?  What is timeline for developing the East Contra Costa Subbasin GSP?  How can stakeholders and interested members of the public stay involved?  Template presentation slides should be primarily visual with accompanying talking points or notes and avoid technical jargon, unless defined in the presentation. Presentation slides may be posted on the centralized or individual GSA websites to inform stakeholders unable to attend public meetings or workshops. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 30 7.2.3.3 Utility Bill Inserts Many GSA members are or serve as utilities that deliver monthly billing statements to customers. These monthly mailings often have space available to insert additional documents at little or no cost to the GSA (if the utility bill’s total weight does not exceed the base rate for first class U.S. Mail). Utility bill inserts are often a single-sheet of paper cut to fit a standard #10 envelope without folding. GSAs in the Subbasin may utilize inserts as needed to inform their customers about upcoming public meetings and workshops, GSP public comment and adoption proceedings, and other SGMA activities. 7.2.3.4 Other Outreach Materials Other SGMA outreach materials may include, but are not limited to, the following:  Fliers  Letterhead  Comment Cards  Sign-in Sheets 7.2.4 Interested Parties Database SGMA requires each GSA to establish and maintain an Interested Party Database. Section 10723.4 of the California Water Code states that any person may request, in writing, to be placed on a list to receive notices regarding GSP preparation, meeting announcements, and availability of draft plans, maps, and other relevant documents. In addition, each GSP must include a description of interested parties within the Subbasin. The GSP has established an Interested Parties Database (Appendix C) for use by all the GSAs. This shared approach provides efficiencies given the number of shared stakeholders and need for consistent communications within the subbasin. GSAs should also develop a process for new stakeholders to add themselves to the database. A separate procedure has also been added to tailor the list specific to a particular GSA if an issue or topic only affects a subset of the subbasin. Interested Parties may self-select to be added to the database through an electronic form located on the GSA or Subbasin SGMA website, or enroll through written request to their GSA. The Interested Parties Database should seek to fully include beneficial users, consistent with California Water Code Section 10723.2 (see Subsection 2.1.1). Interested Parties Databases should be continually updated throughout GSP development and implementation. GSAs within the Subbasin should utilize their own standard mailing lists for publicly noticed meetings and use the Interested Parties Database as the email and mailing list for sending out notices regarding GSA and GSP related meetings, workshops, and other activities. In addition, newsletters or other information regarding GSP milestones should be distributed using the Database. Contra Costa County has developed a centralized email address [groundwaterinfo@dcd.cccounty.us] that will be used for distributing information and receiving comments. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 31 7.2.5 Outreach Venues Database In addition to conducting targeted outreach to beneficial users, GSA should seek to leverage the activities of existing community groups to conduct broader outreach related to SGMA and GSP development. An initial list of outreach venues has been identified by the GSAs and is provided in Section 4.1. GSAs should expand upon this list and maintain a database of existing civic, non-profit, and other community organizations in the Subbasin. This may include:  Local chambers of commerce  Service clubs (e.g. Rotary Club, Lions Club)  Industry associations (e.g. Industrial Association of Contra Costa County, Local Building Industry Association chapters)  Community fairs or farmers markets  Gatherings of elected officials This Outreach Venues Database should identify the organization name, organization type, typical meeting schedule, and contact information of each potential venue. Each group or organization will require a different level of involvement, depending on the group’s interest in and nexus to groundwater management. The Outreach Venues Database may be used to inform stakeholders, receive feedback on GSP development and implementation, or seek collaboration on addressing existing or emerging issues. 7.2.6 Outreach Documentation Pursuant to Section 354.10 of the California Water Code, the GSP must include a list of public meetings public meetings at which the GSP was discussed or considered by the GSA. In addition, the GSP must describes the GSA(s)’ processes for encouraging the involvement of a diverse elements within the subbasin; and identify opportunities for public engagement in the GSA formation, GSP development, and GSP implementation processes. GSAs should maintain a record of all outreach activities related to SGMA. For this GSP, GSAs will provide documentation on a quarterly basis to the technical consultants for incorporation into a master file. This topic should be included as a standing agenda item on the regularly scheduled meetings of the GSP coordination group. The record should document all outreach activities conducted to all stakeholder audiences including, but not limited to:  Presentations to GSA Boards, city councils, boards of supervisors, or other elected bodies  Presentations to stakeholder or community groups or associations  Presentations at any meeting open to members of the public  Public workshops  Newsletters or other regular methods of communications  Distribution of informational materials, including bill inserts  Media alerts, op-eds, or newspaper postings The information in the outreach record should be used to conduct follow-up with stakeholders and as documentation as part of the GSP. The record should include the date, time, audience, and attendance of each activity. The record may also include a list of upcoming outreach and East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 32 local and regional media contacts. GSAs should develop a process for updating the record and consolidating the outreach records for inclusion in the GSP. 7.3 OUTREACH TACTICS GSAs in the Subbasin should conduct a variety of public outreach activities to inform, engage, and respond to stakeholders and other interested parties during GSP development, adoption, and implementation. These activities function to inform stakeholders about SGMA and the GSP, collect information important to groundwater sustainability planning, and receive feedback on the GSP or other public documents. Regular communication with stakeholders and the public will be a key component to the successful adoption and implementation of the GSP. Some outreach activities identified in this section should be timed with GSP development milestones, while others should be conducted on regular or semi-regular basis. GSAs in the Subbasin should collaboratively develop a stakeholder communications and outreach calendar in association with the overall planning schedule. Outreach tools identified in Section 6.2 should be used promote, conduct, and track implementation of the tactics identified in this section. As described in Subsection 7.2.8, all outreach activities described in this section should be documented. 7.3.1 Communications Workbook A separate East Contra Costa Subbasin Communications Workbook (Appendix D) provides lists of required activities for each GSA. The workbook will also assist in document outreach activities. 7.3.2 Outreach Survey A survey to all interested parties was distributed in November-December 2018. The purpose of the survey was two-fold, first to provide some basic GSP education and second to receive input from the interested parties on any topics or concerns for inclusion in the GSP deliberations. The questions were framed to facilitate input on GSP topics. While limited, input provided during the survey was useful. 7.3.3 GSA Board Meetings and Workshops GSA board meetings are the forum where key GSA decisions are presented, discussed, and decided. Presentations at GSA Board meetings also provide an opportunity to engage with the public and stakeholders in the decision-making process for development of the GSP. GSA representatives should verify with their legal counsel whether their GSA board’s meetings are subject to the Brown Act and may be conducted with existing meetings for that agency’s board or elected body (e.g. city council, board of supervisors, board of directors). The GSP Coordination Group members should provide regular updates to their GSA boards regarding the status of GSP development and public outreach activities. These representatives should assess East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 33 their Board’s level of knowledge regarding groundwater topics early in GSP development process and assess the need for a “groundwater 101” type workshop. 7.3.4 Public and Stakeholder Workshops In support of GSP development, GSAs may host workshops to present technical findings, exchange information with stakeholders, and solicit public and stakeholder feedback on the public draft GSP or other public documents. Workshops may be planned and implemented by individuals GSAs or coordinated as a Subbasin-wide activity. Coordinated workshops will be planned at GSP Coordination Group meetings. At this time, it anticipated that individual Boards will have publicly noticed workshop items as part of their regular Board meeting agendas. The workshops will be primarily informational, with the purpose of informing stakeholder and members of public about the basics of SGMA and the GSP development process. Further opportunities for stakeholders to get involved should be identified at that time. The GSAs should hold additional workshops throughout the GSP planning process to inform stakeholders about and receive feedback on key GSP topics. The timing of these workshops should be aligned with key milestones as identified in the project schedule. 7.3.5 Speaking Engagements Efforts should be made to conduct outreach at events or meetings that already occur (e.g. Farm Bureau meetings, Rotary Club, etc.). The purpose of these presentations is to build and maintain awareness about SGMA and the GSP, encourage participation at public GSP development workshops, and encourage enrollment in the Interested Parties Databases. The GSAs should develop a list of knowledgeable presenters in the event that an organization or other entity would like a presentation. Branded outreach materials, such as template presentation slides and handouts, should be readily available for these presenters. The initial round of presentations should focus on increasing awareness of SGMA and expanding the Interested Parties Database. Speaker engagements should be recorded in the overall outreach record and reported at Coordination Group meetings. 7.3.6 Existing Outreach Venues GSAs should fully leverage the activities of existing groups. A list of potential presentation venues is provided in Section 4.1. This list should be developed into a full Outreach Venues Database, described in Subsection 7.2.7. This database should be referenced when there is a need to deploy information. GSAs may conduct informal outreach with the leaders of such groups to determine the best way to interact. GSAs should also determine what communications channels these groups are using and equally leverage these. For example, GSAs may place articles or event postings in group newsletters at little or no charge. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 34 7.3.7 Press Releases and Guest Editorials At some point in the GSP development and implementation process, it is likely that stakeholders will be asked to make changes and/or financially support a sustainability effort. It will be more productive for the GSAs and their GSP collaboration partners to frame discussions about these changes than to have others, perhaps with less knowledge, do so on their behalf. For that reason, there is a need for press releases and/or guest editorials to offer the media and stakeholders accurate information offered in the context of SGMA. This type of outreach should be closely coordinated as consistency in messages is critical to stakeholder acceptance. GSAs may also use press releases, guest editorials, or media alerts to draw media attention to a significant events or GSP milestones. For example, GSAs may use this tactic to promote a public meeting or workshop or alert stakeholders about release of the public draft GSP. 7.4 ITEMS FOR FUTURE CONSIDERATION This Communications Plan outlines an outreach effort based on project and stakeholder needs and preferences. This document has been prepared as a working draft, living document and should be updated as new information and the GSP development process needs are developed.. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 35 8.0 GSP ADOPTION Adoption of a GSA is governed by California Water Code Section 10728.4 and provides the following requirements: A groundwater sustainability agency may adopt or amend a groundwater sustainability plan after a public hearing, held at least 90 days after providing notice to a city or county within the area of the proposed plan or amendment. The groundwater sustainability agency shall review and consider comments from any city or county that receives notice pursuant to this section and shall consult with a city or county that requests consultation within 30 days of receipt of the notice. Nothing in this section is intended to preclude an agency and a city or county from otherwise consulting or commenting regarding the adoption or amendment of a plan. Potential outreach tactics and key milestones during the GSP adoption phase are described below. These tactics and milestones should be identified early in the GSP development process and included as part of the GSP planning schedule. 8.1 GSP ADOPTION PROCEEDINGS 8.1.1 Media Relations, Email, and Social Media The GSAs should notify the public and stakeholders of availability of the Public Draft GSP via email or print notices, (if already used by a GSA) social media posts, and other communication channels established during the GSP development process. At a minimum, beneficial users and individuals on the Interested Parties Database should be notified. The GSAs may also issue a news release or media advisory in advance of and during the public comment period to alert the public and stakeholders to the availability of the Public Draft GSP. 8.1.2 Public Comment Process Pursuant to California Code of Regulations Section 354.10, the GSP must include a summary of comments regarding the GSP, as well as a summary of any responses to those comments by the GSA. The GSAs in the Subbasin should establish a procedure for receiving and responding to comments on the GSP. This may include a public hearing and/or a formal or informal public comment and response period. Public comments and responses to comments on the GSP should be documented and included either directly in or as an attachment or appendix to the plan. The format for the public comment and response process should be adapted to the type and needs of the stakeholders and best use of available GSA resources. Following the public comment process, the GSAs may hold a series of briefings with GSA boards to present the proposed GSP, describe the development and stakeholder engagement process, and provide an overview of public comments. The GSAs should also establish a collaborative process for addressing stakeholder comments on the GSP. East Contra Costa Subbasin Sustainable Groundwater Management Act Communications Plan Dec 2018 36 8.1.3 Newspaper Advertisements Pursuant to Government Code Section 6066, the GSAs must publish two newspaper advertisements at least five days apart, 14 days prior to a public hearing to adopt the GSP. 8.1.4 Public Hearing to Adopt Pursuant to California Water Code Section 10728.4, adoption of the final GSP must occur after a public hearing. This hearing must be preceded by newspaper advertisements pursuant to Government Code Section 6066 and, if required, notification to the California Public Utilities Commission pursuant to California Water Code Section 10727.8(a). 8.2 POST ADOPTION PROCEEDINGS Following submission of the GSP to State, DWR will hold a 60-day public comment period (California Water Code Section 10733.4(c)) for the public, stakeholders and other interested parties on submitted plans. Comments submitted to the State assist in the DWR evaluation of the submitted GSPs and are relayed to the submitting agency for their reference. Tracy Subbasin Sustainable Groundwater Management Act Communications Plan NOV 2018 37 9.0 MEASUREMENTS & EVALUATIONS A guiding principle for evaluation and measurement of the Communications Plan’s success is to provide regular, unbiased reporting of progress toward achieving goals. Success may be evaluated in several ways, including process measures, outcome measures, and an annual evaluation of accomplishments. Optional evaluation measures are described below. 9.1 PROCESS MEASURES Process measures track progress toward meeting the goals of the Communications Plan. These include:  Level of attendance/ participation in outreach activities  Shared understanding of the overarching aims, activities, and opportunities presented by different planning approaches and project activities  Productive dialogue among participants at meetings and events  Sense of authentic engagement; people understand why they have been asked to participate, and feel that they can contribute meaningfully  Timely and accurate public reporting of planning milestones  Feedback from Coordinating Body and GSA members, regulators, stakeholders, and interested parties about the quality and availability of information materials  Level of stakeholder interest in the GSP development process information 9.2 OUTCOME MEASURES Outcome measures track the level of success of the Communications Plan in meeting its overall goals. Some outcome measures considered for the GSP development process include the following:  Consistent participation by key stakeholders and interested parties in essential activities  Participants have no difficulty locating the meetings, and are informed as to when and where they will be held  Responses from meeting participants that the engagement methods provided for a fair and balanced exchange of information  Feedback from interested parties that they understand how their input is used, where to track data, and what results to expect  The project receives quality media coverage that is accurate, complete and fair Tracy Subbasin Sustainable Groundwater Management Act Communications Plan NOV 2018 38 10.0 COMMUNICATION GOVERNANCE Given the relatively large number of stakeholders and the legal requirements for outreach, some form of coordination and communications governance is recommended. Execution of communications activities can be accomplished by an individual or multiple individuals, and/or include or be solely managed by project consultants. The actual form of the governance is less important than a clear understanding of the roles and responsibilities of those responsible for ensuring required communication. Also essential is a clear chain of command that ensures the elected representatives of GSAs are able to retain communications leadership and guidance. A driving consideration for establishing a communications governance structure is the level of effort associated with required activities and the fact that communications are highly time dependent. That means that communications activities should be occurring that may happen outside of regularly scheduled GSA meetings. In this case delegation with guidance to a communications team is efficient and effective. 10.1 ROLES AND RESPONSIBILITIES This GSP development Communications Plan outlines numerous strategies, activities and tactics. While none are highly complex, there is a requirement for coordination and clarity regarding who will be responsible for executing the tasks. A description of the initial key roles and responsibilities is provided below: Responsible Those who do the work to achieve the task. There is at least one person with a role of responsible, although others can be delegated to assist in the work required. Accountable (also approver or final approving authority) This is the person ultimately answerable for the correct and thorough completion of the deliverable or task, and the one who delegates the work to those responsible. There may only be only one accountable specified for each task or deliverable. Consulted Those whose opinions are sought, typically subject matter experts were people that are impacted by the activity; and with whom there is two-way communication. Informed Those who are kept up-to-date on progress, typically on the launch and completion of the task or deliverable. This is one-way communication. Role Distinction Tracy Subbasin Sustainable Groundwater Management Act Communications Plan NOV 2018 39 There is a distinction between a role and the individual assigned the task. Role is a descriptor of an associated set of tasks that could be performed by just one or many people. In the case of the RACI Chart, the team may list as many people as is logical except for the Accountable role. 10.1.1 Initial Roles Initial communication roles (Table 6) have been identified as follows. Table 6. Initial Communication Roles Task Roles & Responsibilities Timeframe GSP Fiscal Agent and Manager Accountable - City of Brentwood. GSAs responsible for providing necessary materials & input All Project Phases Preparation of Information sheets, flyers and other project related Information Consultant team responsible for preparation with review and approval by GSA representatives All Project Phases Website Site maintained by Contra Costa Water District. GSAs and consultants provide approved content to the site. All Project Phases Maintenance of Interested Parties List Consultant maintains list. GSAs and consultants provide approved additions for the list. All Project Phases Planning Outreach meetings to discuss SGMA and expand Interested Parties list Who?) organizes outreach meetings calendar with leaders of existing groups. Notification is sent by via email (CCC) and if no email DWD sends cards. Consultant provides technical support. GSAs provide assistance with list. Meeting documentation sent back to consultant to record. All Project Phases List of presenters Who? to prepare and organize presenters if an All Project Phases Tracy Subbasin Sustainable Groundwater Management Act Communications Plan NOV 2018 40 Task Roles & Responsibilities Timeframe entity would like a presentation Social Media?? Any GSA with Social Media presence will post GSP notices. DAC and EDA outreach Public workshops Press releases and guest editorials Utility bill insert timing and content Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix B Page - 1 - 11.0 LIST OF APPENDICES Appendix A. – Project Schedule Appendix B. Public Outreach Requirements under SGMA Appendix C. – Interested Parties List Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix B Page - 2 - Appendix A. PROJECT SCHEDULE Project Plans Incorporate outreach based on Legal meeting requirements and mindful of key decision points that require stakeholder input. Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix B Page - 3 - Appendix B. Public Outreach Requirements under SGMA GSP Regulations California Code of Regulations Section Public Outreach Requirement § 353.6. Initial Notification (a) Each Agency shall notify the Department, in writing, prior to initiating development of a Plan. The notification shall provide general information about the Agency’s process for developing the Plan, including the manner in which interested parties may contact the Agency and participate in the development and implementation of the Plan. The Agency shall make the information publicly available by posting relevant information on the Agency’s website. 1. Statement of how interested parties may contact the Agency and participate in development and implementation of the plan submitted to DWR. 2. Web posting of same information. Timing: Prior to initiating development of a plan. § 353.8. Comments (a) Any person may provide comments to the Department regarding a proposed or adopted Plan. (b) Pursuant to Water Code Section 10733.4, the Department shall establish a comment period of no less than 60 days for an adopted Plan that has been accepted by the Department for evaluation pursuant to Section 355.2. (c) In addition to the comment period required by Water Code Section 10733.4, the Department shall accept comments on an Agency’s decision to develop a Plan as described in Section 353.6, including comments on elements of a proposed Plan under consideration by the Agency. 1. 60-day comment period for plans under submission to DWR. Comments will be used to evaluate the submission. 2. Parties may also comment on a GSA’s (or GSAs’) statements submitted under section 353.6 Timing: For GSP Submittal - 60 days after submission to DWR § 354.10. Notice and Communication Each Plan shall include a summary of information relating to notification and communication by the Agency with other agencies and interested parties including the following: (a) A description of the beneficial uses and users of groundwater in the basin, including the land uses and property interests potentially affected by the use of groundwater in the basin, the types of parties representing those interests, and the nature of consultation with those parties. (b) A list of public meetings at which the Plan was discussed or considered by the Agency. (c) Comments regarding the Plan received by the Agency and a summary of any responses by the Agency. (d) A communication section of the Plan that includes the following: 1. Statements of issues and interests of beneficial users of basin groundwater, including types of parties representing the interests and consultation process 2. Lists of public meetings 3. Inventory of comments and summary of responses 4. Communication section in plan that includes:  Agency decision making process  ID of public engagement opportunities and response process  Description of process for inclusion  Method for public information related to progress in implementing the plan (status, projects, actions) Timing: For GSP Submittal – with plan For GSP Development – continuous. [Note: activities should be included in the project schedule and information posted on web.] Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix B Page - 4 - California Code of Regulations Section Public Outreach Requirement (1) An explanation of the Agency’s decision-making process. (2) Identification of opportunities for public engagement and a discussion of how public input and response will be used. (3) A description of how the Agency encourages the active involvement of diverse social, cultural, and economic elements of the population within the basin. (4) The method the Agency shall follow to inform the public about progress implementing the Plan, including the status of projects and actions. § 355.2. (c) Department Review of Adopted Plan (c) The Department (DWR) shall establish a period of no less than 60 days to receive public comments on the adopted Plan, as described in Section 353.8. 1. 60-day public review period for public comment on submitted plan. Timing: After GSP Submittal to DWR – 60 days § 355.4. & 355.10 Criteria for Plan Evaluation The basin shall be sustainably managed within 20 years of the applicable statutory deadline consistent with the objectives of the Act. The Department shall evaluate an adopted Plan for compliance with this requirement as follows: (b) (4) Whether the interests of the beneficial uses and users of groundwater in the basin, and the land uses and property interests potentially affected by the use of groundwater in the basin, have been considered. … (10) Whether the Agency has adequately responded to comments that raise credible technical or policy issues with the Plan. 1. Required public outreach and stakeholder information is submitted, including statement of issues and interests of beneficial users. 2. Public and stakeholder comments and questions adequately addressed during planning process. Timing: For GSP Submittal – with plan For resubmittal related to corrective action – with submittal Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix B Page - 5 - California Water Code California Water Code Section Public Outreach Requirement 10720. This part shall be known, and may be cited, as the “Sustainable Groundwater Management Act.” 10720.3 (a) This part applies to all groundwater basins in the state. … (c) The federal government or any federally recognized Indian tribe, appreciating the shared interest in assuring the sustainability of groundwater resources, may voluntarily agree to participate in the preparation or administration of a groundwater sustainability plan or groundwater management plan under this part through a joint powers authority or other agreement with local agencies in the basin. A participating tribe shall be eligible to participate fully in planning, financing, and management under this part, including eligibility for grants and technical assistance, if any exercise of regulatory authority, enforcement, or imposition and collection of fees is pursuant to the tribe’s independent authority and not pursuant to authority granted to a groundwater sustainability agency under this part. 1. Tribes and the federal government may voluntarily participate in GSA governance and GSP development. Timing: Prior to initiating development of a plan. CHAPTER 4. Establishing Groundwater Sustainability Agencies [10723 - 10724] 10723. a) Except as provided in subdivision (c), any local agency or combination of local agencies overlying a groundwater basin may decide to become a groundwater sustainability agency for that basin. (b) Before deciding to become a groundwater sustainability agency, and after publication of notice pursuant to Section 6066 of the Government Code, the local agency or agencies shall hold a public hearing in the county or counties overlying the basin. 1. Must hold public hearing in the county or counties overlying the basin, prior to becoming a GSA Timing: Prior to becoming a GSA. 10723.2 The groundwater sustainability agency shall consider the interests of all beneficial uses and users of groundwater, as well as those responsible for implementing groundwater sustainability plans. These interests include, but are not limited to, all of the following: (a) Holders of overlying groundwater rights, including: (1) Agricultural users. (2) Domestic well owners. (b) Municipal well operators. (c) Public water systems. (d) Local land use planning agencies. 1. Must consider interest of all beneficial uses and users of groundwater. 2. Includes specific stakeholders as listed. Timing: During development of a GSP. Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix B Page - 6 - California Water Code Section Public Outreach Requirement (e) Environmental users of groundwater. (f) Surface water users, if there is a hydrologic connection between surface and groundwater bodies. (g) The federal government, including, but not limited to, the military and managers of federal lands. (h) California Native American tribes. (i) Disadvantaged communities, including, but not limited to, those served by private domestic wells or small community water systems. (j) Entities listed in Section 10927 that are monitoring and reporting groundwater elevations in all or a part of a groundwater basin managed by the groundwater sustainability agency. 10723.4. The groundwater sustainability agency shall establish and maintain a list of persons interested in receiving notices regarding plan preparation, meeting announcements, and availability of draft plans, maps, and other relevant documents. Any person may request, in writing, to be placed on the list of interested persons. 1. Must establish and maintain an interested persons list. 2. Any person may ask to be added to the list Timing: On forming a GSA. 10723.8. (a) Within 30 days of deciding to become or form a groundwater sustainability agency, the local agency or combination of local agencies shall inform the department of its decision and its intent to undertake sustainable groundwater management. The notification shall include the following information, as applicable: … (4) A list of interested parties developed pursuant to Section 10723.2 and an explanation of how their interests will be considered in the development and operation of the groundwater sustainability agency and the development and implementation of the agency’s sustainability plan. 1. Creates notification requirements that include: a. A list of interested parties b. An explanation of how interests will be considered Timing: On forming a GSA & with submittal of GSP 10727.8 (a) Prior to initiating the development of a groundwater sustainability plan, the groundwater sustainability agency shall make available to the public and the department a written statement describing the manner in which interested parties may participate in the development and implementation of the groundwater sustainability plan. The groundwater sustainability agency shall provide the written statement to the legislative body of any city, county, or city and county located 1. Agencies preparing a GSP must prepare a written statement describing the manner in which interested parties may participate in its development and implementation. 2. Statement must be provided to: a. Legislative body of any city and/or county within the geographic area of the plan b. Public Utilities Commission if the geographic area includes a regulated public water system regulated by that Commission c. DWR d. Interested parties (see Section 10927) Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix B Page - 7 - California Water Code Section Public Outreach Requirement within the geographic area to be covered by the plan. The groundwater sustainability agency may appoint and consult with an advisory committee consisting of interested parties for the purposes of developing and implementing a groundwater sustainability plan. The groundwater sustainability agency shall encourage the active involvement of diverse social, cultural, and economic elements of the population within the groundwater basin prior to and during the development and implementation of the groundwater sustainability plan. If the geographic area to be covered by the plan includes a public water system regulated by the Public Utilities Commission, the groundwater sustainability agency shall provide the written statement to the commission. (b) For purposes of this section, interested parties include entities listed in Section 10927 that are monitoring and reporting groundwater elevations in all or a part of a groundwater basin managed by the groundwater sustainability agency. e. The public 3. GSP entities may form an advisory committee for the GSP preparation and implementation. 4. The GSP entities are to encourage active involvement of diverse social, cultural and economic elements of the affected populations. Timing: On initiating GSP 10728.4 Public Notice of Proposed Adoption, GSP Adoption Pubic Hearing A groundwater sustainability agency may adopt or amend a groundwater sustainability plan after a public hearing, held at least 90 days after providing notice to a city or county within the area of the proposed plan or amendment. The groundwater sustainability agency shall review and consider comments from any city or county that receives notice pursuant to this section and shall consult with a city or county that requests consultation within 30 days of receipt of the notice. Nothing in this section is intended to preclude an agency and a city or county from otherwise consulting or commenting regarding the adoption or amendment of a plan. 1. GSP must be adopted or amended at Public Hearing. 2. Prior to Public Hearing for adoption or amendment of the GSP, the GSP entities must: a. Notify cities and/or counties of geographic area 90 days in advance. b. Consider and review comments c. Conduct consultation within 30 days of receipt with cities or counties so requesting 10730 Fees. (a) A groundwater sustainability agency may impose fees, including, but not limited to, permit fees and fees on groundwater extraction or other regulated activity, to fund the costs of a groundwater sustainability program, including, but not limited to, preparation, adoption, and amendment of a groundwater sustainability plan, and investigations, inspections, compliance assistance, enforcement, and program administration, including a prudent reserve. A groundwater sustainability agency shall not impose a fee pursuant to this subdivision on a de minimis extractor unless Related to GSAs 1. Public meeting required prior to adoption of, or increase to fees. Oral or written presentations may be made as part of the meeting. 2. Public notice shall include: a. Time and place of meeting b. General explanation of matter to be considered c. Statement of availability for data required to initiate or amend such fees d. Public posting on Agency Website and provision by mail to interested parties of supporting data (at least 20 days in advance) Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix B Page - 8 - California Water Code Section Public Outreach Requirement the agency has regulated the users pursuant to this part. (b) (1) Prior to imposing or increasing a fee, a groundwater sustainability agency shall hold at least one public meeting, at which oral or written presentations may be made as part of the meeting. (2) Notice of the time and place of the meeting shall include a general explanation of the matter to be considered and a statement that the data required by this section is available. The notice shall be provided by publication pursuant to Section 6066 of the Government Code, by posting notice on the Internet Web site of the groundwater sustainability agency, and by mail to any interested party who files a written request with the agency for mailed notice of the meeting on new or increased fees. A written request for mailed notices shall be valid for one year from the date that the request is made and may be renewed by making a written request on or before April 1 of each year. (3) At least 20 days prior to the meeting, the groundwater sustainability agency shall make available to the public data upon which the proposed fee is based. (c) Any action by a groundwater sustainability agency to impose or increase a fee shall be taken only by ordinance or resolution. (d) (1) As an alternative method for the collection of fees imposed pursuant to this section, a groundwater sustainability agency may adopt a resolution requesting collection of the fees in the same manner as ordinary municipal ad valorem taxes. (2) A resolution described in paragraph (1) shall be adopted and furnished to the county auditor-controller and board of supervisors on or before August 1 of each year that the alternative collection of the fees is being requested. The resolution shall include a list of parcels and the amount to be collected for each parcel. (e) The power granted by this section is in addition to any powers a groundwater sustainability agency has under any other law. 3. Mailing lists for interested parties are valid for 1 year from date of request and may be renewed by written request of the parties on or before April 1 of each year. 4. Includes procedural requirements per Government Code, Section 6066. Timing: Prior to adopting fees. Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix B Page - 9 - California Government Code CODE PUBLIC OUTREACH REQUIREMENT 6060 Whenever any law provides that publication of notice shall be made pursuant to a designated section of this article, such notice shall be published in a newspaper of general circulation for the period prescribed, the number of times, and in the manner provided in that section. As used in this article, “notice” includes official advertising, resolutions, orders, or other matter of any nature whatsoever that are required by law to be published in a newspaper of general circulation. 6066 Publication of notice pursuant to this section shall be once a week for two successive weeks. Two publications in a newspaper published once a week or oftener, with at least five days intervening between the respective publication dates not counting such publication dates, are sufficient. The period of notice commences upon the first day of publication and terminates at the end of the fourteenth day, including therein the first day. 1. Must publish notices in a newspaper of general circulation as prescribed. 2. Publication shall be once a week for two successive weeks. Two publications in a newspaper published once a week or oftener, with at least five days intervening between the respective publication dates not counting such publication dates, are sufficient. 3. The period of notice begins the first day of publication and terminates at the end of the fourteenth day, (which includes the first day.) Timing: Prior to adopting fees Appendix C - Page 1 Appendix C. Interested Parties HOLDERS OF OVERLYING GROUNDWATER RIGHTS (1) Agricultural Users  Contra Costa County Farm Bureau  East Contra Costa Irrigation District  Contra Costa County Agricultural Commissioner  Ron Nunn Farms  RRS Farms  Dwelley Farms  Mr. Stuart  Ron Nunn  Eugene Mangini,  Marian & Louis Mangini,  Louis Volpone,  David Roche,  Pierina Maggiora,  Reclamation Districts (RD) o RD 799 (Hotchkiss Tract) o RD 800 (Byron Tract) o RD 830 (Jersey Island) o RD 2024 (Orwood and Palm Tracts) o RD 2025 (Holland Tract) o RD 2026 (Webb Tract) o RD 2059 (Bradford Island) o RD 2065 (Veale Tract) o RD 2090 (Quimby Island) o RD 2117 (Coney Island) o RD 2121 (Bixler Tract) o RD 2137 (2) Domestic Well Owners  Mr. Shatting  Mr. Critchfield  Mr. Rozenski  Mr. Larson  Mr. & Mrs. Driscoll  MS. Lomax  Mr. & Mrs. Boro  Mr. & Mrs. Gil  Gang Sun  Ernest Rodriguez  Ernest Dominguez  Ronald Stinnette  Frank Williams  Luis Colmenares  Walter Li  Sengchanh Panyachith  Suzan M Ferrer  Ron & Jean Tennison  Arturo Martinez  Susan Corrie  Esthela Rodriguez  L L G Group  Josefina Torres  Juan Rivera  Agripina Valle  Jennifer Vallis  Jim & Cheryl Hammers  Oscar Hernandez  Jesus Campos  Louden LLC  Lee Munoz  Arcangel Camacho  Profirio Medina  Baymark Financial Inc  Pat Vanden Broek  Margarito Meza  Eric Avalos  Alicia Cruz  Mario Sanchez Gonzale  Esperanza Lopez  Cinda Nagel  Victor Chavez  Tiana Flores  Francisco Sanchez  Mario Cabada  Anna Rivera  Elia Garcia  Jose L. Cabada  Thomas Trimble  Brian Stewart  Tammi Van Alstyne  Lela Peterson  Harvest Time Assembly  Lone Tree Drive Inn  Irma Gamez  Wes Tilton  Claire Keith Appendix C - Page 2  Pedro Guitron  Maria Aguayo  Michael Mcpoland  Randy Peterson  Ian Robertson  Kim Silva  Delta Fence C/O Martin II  Rodney L Kraber  Francisca Sandoval  Daniel Mendoza  Salome Quintanilla  Esperanza Magana  Alice Bloodworth  Michael W Driskill  Christine Curiel  Jim Price Heidolf Property  Tim Bigelow  Kristin Pipkins  Darlene Gonzalez  Marcial Cruz  Gloria Mcgarath  Annette Beckstrand  Josefina Zesati (3) Municipal Well operators or Systems  City of Brentwood  City of Oakley  Discovery Bay Community Services District (4) Public Water Systems.  Aloha Club  Flamingo Mobile Manor SWS  Anchor Marina SWS  Frank's Marina  Angler's Ranch #3 - SWS  Gas N Save  Angler's Subdivision #4  Holland Riverside Marina Water  Bay Standard Water System  Knightsen Community Water Sys  Beacon West Water System  Knightsen Elementary School  Bethel Baptist Church -SWS  Lazy M Marina  Bethel Harbor  Lindquist Landing Marina SWS  Bethel Island Golf Course  Lone Tree Medical & Dental SWS  Bethel Island Mutual Water Co  Mac's Old House  Bethel Market  Marin Food Specialties SWS  Bethel Missionary Baptist  Marina Mobile Manor SWS  Big Oak Mobile Home Park Water  Neighborhood Church SWS  Brentwood Creek Farm - Farm Land LP  New Life Marina  Bridgehead Cafe  Oakley Mutual Water Company  Byron Airport Water System  Orin Allen Youth Rehab Facility  Byron Corners Inc SWS  Orwood Resort  Byron Inn Cafe Water System  Pleasantimes Mutual Water Co  Byron United Methodist Church  Riverview Water Association  Camino Mobile Home Park  Russo's Mobile Park  Cecchini Water Service - Farm Land LP Delete  Sandmound Mutual  Colonia Santa Maria  Sandy Point Mobile Home Park  Country Junction Deli  Sugar Barge Water System  Cruiser Haven Marina - SWS  Sunset Harbor  Delta Bar & Grill  Tess' Farm Market  Delta Mutual Water Company  Tugs Boat House Lounge  Delta Sportsman  Wahl Family Water System  Doc's Marina  Willow Mobile Home Park - SWS  Dutch Slough Water Works  Willow Park Marina - SWS  EBRPD Round Valley Water Sys  Willowest Marina WS  Excelsior Middle School  City Of Antioch  Farrar Park Water System  City Of Brentwood Appendix C - Page 3  Town of Discovery Bay  Contra Costa Water District  Santiago Island Village  Diablo Water District (5) Local Land Use Planning Agencies.  Contra Costa County  City of Oakley  City of Antioch  City of Brentwood (6) Environmental Users of Groundwater  East Bay Regional Park District, Big Break  Dutch Slough Restoration Project  Contra Costa Watershed Forum  Contra Costa County Watershed Program (CWP)  East Contra Costa Habitat Conservancy (7) Surface Water Users (if there is a hydrologic connection between surface and groundwater bodies)  City of Antioch  Contra Costa Water District  East Contra Costa Irrigation District  Byron Bethany Irrigation District (8) The Federal Government (including, but not limited to, the military and managers of federal lands)  U.S. Bureau of Reclamation  US Fish & Wildlife (9) California Native American Tribes  Wilton Rancheria Tribe  Bay Miwok Tribe (10) Disadvantaged Communities All residents on Bethel Island* (11) Entities listed in Section 10927 (monitoring and reporting groundwater elevations in all or a part of a groundwater basin managed by the groundwater sustainability agency).  Statewide Groundwater Elevation Monitoring (CASGEM) data with DWR for Eastern Contra Costa County. (12) Other:  Delta Diablo Sanitary District  Iron House Sanitary District  Knightsen Town Advisory Council Appendix D Workbook - i Appendix D. East Contra Costa Subbasin Communication Plan Workbook East Contra Costa Subbasin Communication Plan Workbook Contents  1. Mandated SGMA Outreach Activities ........................................................................................... ii  2. Beneficial Use.............................................................................................................................. 3  3. Land Use and Property Interests ................................................................................................. 3  4. Meeting Records ......................................................................................................................... 3  5. GSP Plan Comments .................................................................................................................. 4  6. Communications Section ............................................................................................................. 4  7. GSP Checksheet ......................................................................................................................... 5  8. Legally required GSA /GSP Web Posting Requirements ........................................................ - 8 -  9. Outreach Venues ................................................................................................................... - 11 -  Appendix D Workbook - ii 1. Mandated SGMA Outreach Activities Timeframe Item Prior to initiating plan development Statement of how interested parties may contact the Agency and participate in development and implementation of the plan submitted to DWR. Web posting of same information. Prior to plan development Must establish and maintain an interested persons list. Must prepare a written statement describing the manner in which interested parties may participate in GSP development and implementation. Statement must be provided to: Legislative body of any city and/or county within the geographic area of the plan Public Utilities Commission if the geographic area includes a regulated public water system regulated by that Commission DWR Interested parties (see Section 10927) The public Prior to and with GSP submission Statements of issues and interests of beneficial users of basin groundwater, including types of parties representing the interests and consultation process Lists of public meetings Inventory of comments and summary of responses Communication section in plan that includes: Agency decision making process Identification of public engagement opportunities and response process Description of process for inclusion Method for public information related to progress in implementing the plan (status, projects, actions) 90 days prior to GSP Adoption Hearing Prior to Public Hearing for adoption or amendment of the GSP, the GSP entities must notify cities and/or counties of geographic area 90 days in advance. 90 days or less prior to GSP Adoption Hearing Prior to Public Hearing for adoption or amendment of the GSP, the GSP entities must:  Consider and review comments  Conduct consultation within 30 days of receipt with cities or counties so requesting GSP Adoption or Amendment GSP must be adopted or amended at Public Hearing. 60 days after plan submission 60-day comment period for plans under submission to DWR. Comments will be used to evaluate the submission. Prior to adoption of fees Public meeting required prior to adoption of, or increase to fees. Oral or written presentations may be made as part of the meeting. Public notice shall include: Time and place of meeting General explanation of matter to be considered Statement of availability for data required to initiate or amend such fees Public posting on Agency Website and provision by mail to interested parties of supporting data (at least 20 days in advance) Mailing lists for interested parties are valid for 1 year from date of request and may be renewed by written request of the parties on or before April 1 of each year. Includes procedural requirements per Government Code, Section 6066. Prior to conducting a fee adoption hearing. Must publish notices in a newspaper of general circulation as prescribed. Publication shall be once a week for two successive weeks. Two publications in a newspaper published once a week or oftener, with at least five days intervening between the respective publication dates not counting such publication dates, are sufficient. The period of notice begins the first day of publication and terminates at the end of the fourteenth day, (which includes the first day.) Appendix D Workbook - 3 GSP COMMUNICATIONS WORKBOOK California Code of Regulations Section 354.10 states that each Plan shall include a summary of information relating to notification and communication by the Agency with other agencies and interested parties. GSP Submittal Requirements Table 6. GSP Submittal Requirements3 2. Beneficial Use Description of the beneficial use(s) Users of groundwater (as related to the beneficial activity) 3. Land Use and Property Interests Land uses and property interests potentially affected by the use of groundwater in the basin Types of parties representing those interests Nature of consultation with those parties. 4. Meeting Records 3 Guidance Document for the Sustainable Management of Groundwater, Preparation Checklist for GSP Submittal, Department of Water Resources, December 2016 GSP Regulations Section Requirement Description  Article 5. Plan Contents, Sub-article 1. Administrative Information 354.10 Notice and Communicatio n • Description of beneficial uses and users • List of public meetings with dates • GSP comments and responses • Decision-making process • Public engagement process • Method(s) to encouraging active involvement • Steps to inform the public on GSP implementation progress Appendix D Workbook - 4 List of public meetings at which the Plan was discussed or considered by the Agency. DATE LOCATION CONVENER TOPIC(S) 5. GSP Plan Comments DATE AGENCY COMMENTER/ COMMENT RESPONSE 6. Communications Section Agency’s decision-making process Identification of opportunities for public engagement How public input and response will be used How the Agency encourages the active involvement of diverse social, cultural and economic elements of the population Method the Agency follows to inform the public about progress Method the Agency follows to inform the public about implementation, including the status of projects and actions Appendix D Workbook - 5 7. GSP Checksheet Following Is a summary of requirements for Groundwater Sustainability Plans (GSP) that focus on plan elements with some form of decision making or discretionary activity associated with that section of the plan.  Thinking about the community and its interests, what types of questions need to be addressed for this section of the plan to be adequate?  What, if any, minimum standards or best practices should be considered as this plan section is prepared?   Technical and Reporting Standards Issues, Interests, Needs, Options Article 3. 352.2  Monitoring Protocols  • Monitoring protocols adopted by the GSA for data collection and management   Monitoring protocols that are designed to detect changes in groundwater levels, groundwater quality, inelastic surface subsidence for basins for which subsidence has been identified as a potential problem, and flow and quality of surface water that directly affect groundwater levels or quality or are caused by groundwater extraction in the basin        Administrative Information Issues, Interests, Needs, Options Article 5. 354.8(f)  10727.2(g)  Land Use Elements or Topic Categories of Applicable General Plans  • Summary of general plans and other land use plans  • Description of how implementation of the GSP may change water demands or affect achievement of sustainability and how the GSP addresses those effects  • Description of how implementation of the GSP may affect the water supply assumptions of relevant land use plans  • Information regarding the implementation of land use plans outside the basin that could affect the ability of the Agency to achieve sustainable groundwater management    Appendix D Workbook - 6 Administrative Information Issues, Interests, Needs, Options 354.14 Hydrogeologic Conceptual Model • Selection/Description of the Hydrogeologic Conceptual Model    354.18 10727.2(a)(3) Water Budget Information • Description of inflows, outflows, and change in storage  • Quantification of overdraft  • Estimate of sustainable yield  • Quantification of current, historical, and projected water budgets       354.24 Sustainability Goal • Description of the sustainability goal    354.28 10727.2(d)(1)  10727.2(d)(2) Minimum Thresholds • Description of each minimum threshold and how they were established for each sustainability indicator  • Relationship for each sustainability indicator  • Description of how selection of the minimum threshold may affect beneficial uses and users of groundwater  • Standards related to sustainability indicators  • How each minimum threshold will be quantitatively measured   354.44 Projects and Management Actions • Description of projects and management actions that will help achieve the basin’s sustainability goal  • Measurable objective that is expected to benefit from each project and management action  • Circumstances for implementation  • Public noticing  • Permitting and regulatory process  • Time‐table for initiation and completion, and the accrual of expected benefits  • Expected benefits and how they will be evaluated  • • Management of groundwater extractions and recharge   354.44(b)(2) 10727.2(d)(3  • Overdraft mitigation projects and management actions    Appendix D Workbook - 7  The GSP also includes additional planning elements involving descriptions of existing conditions, features, activities and jurisdictional topics.  Those sections are based on existing factual information and should be reviewed for tone, approach, accuracy, and completeness. Thinking about the GSP planning requirements that involve descriptions of existing conditions, features, activities and jurisdictional topics what issues, interests, needs and/or options would you and/or your community like considered in the planning process? Administrative Information Issues, Interests, Needs, Options 354.10 Notice and Communication • Description of beneficial uses and users  • List of public meetings  • GSP comments and responses  • Decision‐making process  • Public engagement  • Encouraging active involvement  • Informing the public on GSP implementation progress   354.20 Management Areas Reason for creation of each management area  • Minimum thresholds and measurable objectives for each management area  • Level of monitoring and analysis  • Explanation of how management of management areas will not cause undesirable results outside the management area  • Description of management areas  Note (may not apply) 354.26 Undesirable Results • Description of undesirable results  • Cause of groundwater conditions that would lead to undesirable results  • Criteria used to define undesirable results for each sustainability indicator  • Potential effects of undesirable results on beneficial uses and users of groundwater   10727.2(d)(5) Surface Water Supply • Description of surface water supply used or available for use for groundwater recharge or in‐lieu use     Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix D Page - 8 - 8. Legally required GSA /GSP Web Posting Requirements GSP Code Section Item to be Posted Responsible Timing  § 353.6. Initial Notification 1. General information about the Agency’s process for developing the Plan 2. Manner in which interested parties may contact the Agency 3. How parties may participate in the development and implementation of the Plan GSP developing agencies Prior to initiating plan development Water Code Section Item to be Posted Responsible Timing  §10725.2(c) 1. In addition to any other applicable procedural requirements, provide notice of the proposed adoption of the groundwater sustainability plan and provide for electronic notice to any person who requests electronic notification. GSA Prior to adoption § 10730 Fees 1. Notice of the time and place of meetings involving imposition or increasing of fees 2. General explanation of the matter to be considered 3. Statement that the data required by this section is available and the method by which to acquire it. Agency imposing or increasing fees Prior to imposing or increasing a fee Government Code Section Item to be Posted Responsible Timing  § 54954.2 Agendas 1. Post Meeting Agenda Requirements a. Direct link must be standalone and cannot only be part of a "contextual" menu which would require users to search for the link on the website - If a direct link is provided, then a second Any local agency subject to Brown Act (Note – only applies to agencies with a website; however, under SGMA After January 1, 2019 72 hours in Advance of a Regular Meeting Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix D Page - 9 - link can be provided in a contextual menu. b. If an agency uses an integrated agenda management platform that is specifically for posting board agenda meetings, then the agency does not have to comply with this requirement if: i. the agency posts a direct link to the platform which contains the agency agenda on its primary website; ii. the current agenda is the first available at the top of the platform; and iii. the agency complies with specific open format requirements. c. Agenda must be in a format that is retrievable, downloadable, index able, and electronically searchable by commonly used Internet search applications. d. Must be platform independent, machine readable, and in a form that is available free of charge to the public so that they may reuse or redistribute the agenda. (For example - PDF) the GSP agencies are required to have a website.) Other - Optional Government Code Section Item to be Posted Responsible Timing  § 6253 Public Records Request 1. Allows for agencies to post documents subject to a Public Records Act request on the web and for the web location to be given as a reference in lieu of the document. frequently requested documents Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix D Page - 10 - a. Provides an exception for individual requestors without internet access Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix D Page - 11 - California Government Code Requirements ‐ Newspapers    CODE PUBLIC OUTREACH REQUIREMENT  6060 Whenever any law provides that publication of notice shall be made pursuant to a designated section of this article, such notice shall be published in a newspaper of general circulation for the period prescribed, the number of times, and in the manner provided in that section. As used in this article, “notice” includes official advertising, resolutions, orders, or other matter of any nature whatsoever that are required by law to be published in a newspaper of general circulation. 6066 Publication of notice pursuant to this section shall be once a week for two successive weeks. Two publications in a newspaper published once a week or oftener, with at least five days intervening between the respective publication dates not counting such publication dates, are sufficient. The period of notice commences upon the first day of publication and terminates at the end of the fourteenth day, including therein the first day. 4. Must publish notices in a newspaper of general circulation as prescribed. 5. Publication shall be once a week for two successive weeks. Two publications in a newspaper published once a week or oftener, with at least five days intervening between the respective publication dates not counting such publication dates, are sufficient. 6. The period of notice begins the first day of publication and terminates at the end of the fourteenth day, (which includes the first day.) Timing: Prior to adopting fees 9. Outreach Venues GSA representatives have identified a list of potential outreach venues in the Subbasin, shown in Table 2 Table 7. Potential Outreach Venues in the Tracy Subbasin  Organization/Event Name Type of Organization/Event Location Contra Costa County Farm Bureau Agricultural Contra Costa County Brentwood Lions Club Civic/Community Brentwood Discovery Bay Chamber of Commerce Commercial Discovery Bay Oakley Chamber of Commerce Commercial Oakley Discovery Bay Lions Club Civic/Community Discovery Bay Earth Day Event Multiple locations throughout Subbasin Brentwood City Council Government/Municipal Brentwood Brentwood Planning Commission Government/Municipal Brentwood Contra Costa County Board of Supervisors Government/Municipal Contra Costa County Contra Costa County Municipal Advisory Council – Byron and Bethel Island Government/Municipal Contra Costa County Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix D Page - 12 - Contra Costa County Municipal Advisory Council - Knightsen Government/Municipal Contra Costa County Contra Costa County Transportation, Water, Infrastructure Committee Government/Municipal Contra Costa County Oakley City Council Government/Municipal Oakley Building Industrial Association - East Bay Chapter Industrial Contra Costa County Industrial Association of Contra Costa County Industrial Contra Costa County Farmers Market Other Brentwood East County Water Management Association Board Meeting Other Contra Costa County Realtor groups Other Multiple locations throughout Subbasin Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix D Page - 13 - Interbasin Coordination under the Sustainable Groundwater Management Act (SGMA) Agencies preparing a Groundwater Sustainability Plan (GSP) under SGMA are encouraged to work with other agencies in adjacent basins to facilitate exchange of technical information, assist with preparation of GSPs, coordinate basin boundary modifications, and conduct outreach to regional stakeholders. Interbasin coordination is also important to ensure that implementation of a GSP will not adversely affect an adjacent basin’s ability to implement is GSP or impede its ability to achieve its sustainability goal. GSAs may develop a voluntary Interbasin Agreement to establish compatible sustainability goals and understanding regarding the fundamental elements of each agency’s GSP. Interbasin agreements should facilitate the exchange of technical information between agencies and include a process to resolve disputes concerning the interpretation of that information. (23 CCR § 357.2). A summary of elements to be included in an interbasin agreement is provided below. Interbasin Coordination Agreement Checklist Interbasin Coordination Agreement Element CA Code of Regulations General Information Identity of each basin participating in and covered by the terms of the agreement. 23 CCR § 357.2 (a)(1) A list of the Agencies or other public agencies or other entities with groundwater management responsibilities in each basin. 23 CCR § 357.2 (a)(2) A list of the Plans, Alternatives, or adjudicated areas in each basin. 23 CCR § 357.2 (a)(3) Technical Information An estimate of groundwater flow across basin boundaries, including consistent and coordinated data, methods and assumptions. 23 CCR § 357.2 (b)(1) An estimate of stream-aquifer interactions at boundaries. 23 CCR § 357.2 (b)(2) A common understanding of the geology and hydrology of the basins and the hydraulic connectivity as it applies to the Agency's determination of groundwater flow across basin boundaries and description of the different assumptions utilized by different Plans and how the Agencies reconciled those differences. 23 CCR § 357.2 (b)(3) Sustainable management criteria and a monitoring network that would confirm that no adverse impacts result from the implementation of the Plans of any party to the agreement. If minimum thresholds or measurable objectives differ substantially between basins, the agreement should specify how the Agencies will reconcile those differences and manage the basins to avoid undesirable results. The Agreement should identify the differences that the parties consider significant and include a plan and schedule to reduce uncertainties to collectively resolve those uncertainties and differences. 23 CCR § 357.2 (b)(4) Conflict Resolution A description of the process for identifying and resolving conflicts between Agencies that are parties to the agreement. 23 CCR § 357.2 (c) Submission to DWR Tracy Subbasin Sustainable Groundwater Management Act Communications Plan SEP 2018 Appendix D Page - 14 - Interbasin Coordination Agreement Element CA Code of Regulations Interbasin agreements submitted to the Department shall be posted on the Department's website. 23 CCR § 357.2 (d) RESOLUTION OF THE CONTRA COSTA COUNTY BOARD OF SUPERVISORS TO ADOPT A GROUNDWATER SUSTAINABILITY PLAN FOR THE EAST CONTRA COSTA SUBBASIN, (5-22.19 SAN JOAQUIN VALLEY) Recitals A. WHEREAS, in August 2014, the California Legislature passed, and in September 2014 the Governor signed legislation creating the Sustainable Groundwater Management Act (“SGMA”) to provide local groundwater sustainability agencies with the authority and technical and financial assistance necessary to sustainably manage groundwater (Wat. Code, §10720, (d)); and B. WHEREAS, SGMA requires sustainable management through the development of groundwater sustainability plans (“GSPs”), which can be a single plan developed by one or more groundwater sustainability agencies (“GSAs”) or multiple coordinated plans within a basin or subbasin (Wat. Code, §10727); and C. WHEREAS, SGMA requires a GSA be formed to manage groundwater in all basins designated by the California Department of Water Resources (“DWR") as a medium or high priority subbasin; and D. WHEREAS, on April 25, 2017, the Contra Costa County Board of Supervisors (“County”) became the groundwater sustainability agency for portions of the Tracy Subbasin that are in Contra Costa County; and E. WHEREAS, the City of Antioch, City of Brentwood, Byron-Bethany Irrigation District, Contra Costa Water District (“CCWD”), Diablo Water District, Discovery Bay Community Services District, and East Contra Costa Irrigation District, were formed as GSAs [except CCWD] for the purposes of sustainably managing groundwater in the Tracy Subbasin within their jurisdictional boundaries that are in Contra Costa County, pursuant to the requirements of SGMA; and F. WHEREAS, the GSAs have the authority to draft, adopt, and implement a Groundwater Sustainability Plan (Wat. Code, §10725 et seq.); and G. WHEREAS, on May 9, 2017, the GSAs entered a Memorandum of Understanding with other GSAs within the Tracy Subbasin along with CCWD for the purpose of jointly developing a single GSP for the portion of the subbasin within Contra Costa County and coordinating sustainable groundwater management in the Subbasin (Wat. Code, §10727(a)(2)); and H. WHEREAS, the Brentwood GSA submitted an Initial Notification to DWR on behalf of all the GSAs to jointly develop a GSP for the Subbasin on February 12, 2018; and 2 I. WHEREAS, on February 11, 2019, the California Department of Water Resources approved dividing the Tracy Subbasin into two subbasins (e.g., East Contra Costa Subbasin and the Tracy Subbasin) thereby creating a separate groundwater basin entirely within Contra Costa County called the East Contra Costa Subbasin, (DWR Basin 5 - 22.19, San Joaquin Valley). J. WHEREAS, on April 13, 2020, the GSAs and CCWD entered into an Amended and Restated Memorandum of Understanding to ensure clarity for future decisions by the Board the reflect DWRs determination that, for purposes of SGMA, the East Contra Costa Subbasin is separate and distinct from other portions of the Tracy Subbasin; and K. WHEREAS, a group (“Working Group”) consisting of the GSAs and CCWD has coordinated in the Subbasin to draft a single GSP; and L. WHEREAS, the County on June 9, 2021, via certified mail, sent the Notice of Intent to adopt a groundwater sustainability plan pursuant to Water Code §10728.4; and M. WHEREAS, on behalf of the GSAs, the Working Group developed the draft GSP and released portions of the draft GSP for public and local agency review during GSP development and released the entire draft on September 7, 2021; and N. WHEREAS, the Working Group reviewed and responded to comments on the draft GSP; and O. WHEREAS, the Working Group released the final GSP on October 15, 2021, which is attached and herby incorporated into this resolution as Exhibit A; and P. WHEREAS, on October 15, 2021, the Working Group recommended each of the GSAs adopt the final GSP for their respective jurisdictions. NOW, THEREFORE, be it RESOLVED, by the Contra Costa County Board o f Supervisors as follows: 1. Contra Costa County is the Groundwater Sustainability Agency for portions of the East Contra Costa Subbasin (DWR Basin 5 -22.19) and hereby adopts the final Groundwater Sustainability Plan dated October 15, 2021, as attached in Exhibit “X”. 2. The California Environmental Quality Act is not applicable to the preparation and adoption of a Groundwater Sustainability Plan, Section 10728.6 of the Public Resources Code. 3 3. Authorizes the Director of Conservation and Development, or designee, to take such actions as may be reasonably necessary to submit the East Contra Costa Groundwater Sustainability Plan to DWR by January 31, 2022. Attachments: Exhibit A – Final East Contra Costa Groundwater Sustainability Plan dated October 15, 2021 East Contra Costa Subbasin Groundwater Sustainability Plan Transportation, Water and Infrastructure Committee Public Meeting November 8, 2021 9:00 AM East Contra Costa Subbasin and SGMA Vicki Kretsinger, Luhdorff & Scalmanini Consulting Engineers •In 2014, the state passed the Sustainable Groundwater Management Act –SGMA •SGMA requires groundwater to be managed by local public agencies called Groundwater Sustainability Agencies –GSA •GSAs are responsible to ensure a groundwater basin is managed sustainably •Sustainable management is conducted through the Groundwater Sustainability Plan -GSP Introduction to SGMA 3 Introduction to SGMA 4 The GSP (Plan) is a plan to ensure that groundwater is sustainably managed over a 50-year planning and implementation horizon 5 Sustainability Indicators Avoiding Groundwater Conditions that Cause Significant and Unreasonable….. What a GSP is and is not 6 East Contra Costa Groundwater Subbasin -has domestic, urban, agricultural and industrial uses, plus groundwater dependent ecosystems Who the GSP affects •affect or change water rights •regulate individual domestic well owners (less than 2 AF or 650,000 gallons) •mitigate pre-existing or native features of groundwater such as water quality 7 The GSP does not : What a GSP is not •Also, it is not: •A land use plan •An environmental restoration plan •A flood control plan •Part of the Delta Conveyance Project 8 What a GSP is 9 The GSP is a plan to: •ensure adequate groundwater supply for all beneficial uses and users in the Subbasin •manage groundwater under climate change, sea level rise, and drought •protect vulnerable users •protect groundwater dependent ecosystems What a GSP is 10 Under SGMA, GSAs have authorities to enact sustainability measures including: •Well monitoring •Metering •Pumping fees (does not apply to de minimis users) •Well spacing restrictions Plan Sections 1.Introduction –Responsible Agencies 2.Plan Area –Water Resources, Land Use Elements, Environment 3.Basin Setting –Hydrogeology, Groundwater and Surface Water Conditions 4.Water Supply –Historical, Current, and Projected 5.Water Budget –Historical, Current and Projected Scenarios 6.Monitoring Networks –Sustainability Indicators 7.Sustainable Management Criteria –Goals 8.Projects and Management Actions –Implemented As-Needed 9.Plan Implementation –Budget and funding 10.Notice and Communication What a GSP is 11 Agency Information •What is a GSA? •ECC GSA Information: 7 GSAs and CCWD •History of coordination and stewardship of East Contra Costa County water resources, including IRWMs and Basin Boundary Modification 13 Sustainability Goal for the ECC Subbasin •To protect and maintain safe and reliable sources of groundwater for all beneficial uses and users. •To ensure current and future groundwater demands are met under climate change. •To establish and protect sustainable yield by achieving measurable objectives set forth in this GSP over the 50-year implementation and planning horizon. •Avoid undesirable results. Groundwater Sustainability Plan Sections 1.Notice of Intent to Adopt (NOI) –Required 90 days prior to adoptions (sent prior to July 1, 2021) 2.Final Public Comment Period on Public Draft of entire GSP –September 7 to October 6, 2021 3.Publish Final GSP –October 15, 2021 4.Adoption –Each GSAs shall adopt the Final GSP (October 15- Dec. 15) 5.Deadline –Submit GSP to state DWR January 31, 2022 Process for Adopting a GSP 14 Why the Plan is Important •Maintain sustainable groundwater management •Protect your well •Maintain local control •Eligibility for benefits •Coordination with other planning processes Key Findings 16 The ECC Subbasin is in a stable condition 1. Chronic Groundwater Level Lowering Not present 2. Groundwater Storage Stable 3. Seawater Intrusion Not present 4. Groundwater Quality No degradation due to pumping 5. Land Subsidence due to groundwater pumping Not present 6. Surface Water Depletion due to groundwater pumping Not Present Key Findings: ECC Subbasin Conditions 17 •The ECC Subbasin has a high amount of naturally occurring salts and minerals •The GSP does not mitigate existing water quality issues, but it does protect and maintain safe and reliable sources of groundwater for all beneficial uses •Accomplished through monitoring, setting minimum thresholds, and developing actions •For more information, see GSP Sections 3 and 7 18 Key Findings: Water Quality Key Finding: Saltwater Intrusion •Saltwater intrusion is NOT present. The ECC Subbasin is not adjacent to a coastal aquifer •There is a potential for future bay water intrusion •Sea level rise •Regulatory changes •Baywater intrusion is being monitored 19 Key Findings: ECC Subbasin Future Conditions 20 •Even under much higher pumping, groundwater storage and levels are sustainable •Well capacity is unaffected GSP Implementation 21 22 GSP Implementation: Monitoring commences now RepresentativeBasin-Wide Monitoring Network –Water Quality 23 Monitoring Network –other basin concerns Groundwater dependent ecosystems Public water systems Delta connections 4 new monitoring sites under state grant 24 Water budget and groundwater flow model A groundwater flow model was developed to evaluate: •Water Budget Components •Future Scenarios •Sustainable Yield 25 Future Scenarios •DWR Produced SGMA Guidance Document o Provides adjustment data for different climate change scenarios o Pick a historic simulation period and apply the adjustments over a 50-year period o Scenarios for far-future 2070 central tendency •Climate Change and Sea Level Rise •Local Management Actions/Projects Predictive Future Model Scenarios 50-year Future Climate Change Management Actions/Projects 26 Modeling Sustainable Yield Sustainable Yield Scenarios •Reduced surface water deliveries and increased groundwater pumping until undesirable results arise for sustainability indicator(s) •Basin outflow and stream depletion indicators affected before storage and water level declines •Sustainable yield on the order of 55 percent higher than historical base period (1997-2018) ECC Subbasin Conditions •Groundwater demand is 15 % of total, rest is surface water •Even under much higher pumping, groundwater storage and levels are sustainable •This provides opportunities to use groundwater conjunctively to provide reliability to the overall supply 27 Deep Zone Shallow Zone Historical perspective Local agencies monitor water levels and water quality to understand groundwater conditions in the subbasin o Have observed regionally stable groundwater conditions 28 Deep Zone Shallow Zone Local Issues 29 Protecting rural domestic users: The GSP seeks to avoid impacts that cause: •a need to lower a well pump to ”chase water,” to replace a pump, or to deepen or replace a well. •wells going “dry” •water level declines due to well pumping interference Section 8-Projects and Management Actions 30 GSAs may develop projects and management actions for sustainability Projects might include: o Groundwater recharge o Conjunctive use of surface water and groundwater o Water exchanges Management Actions might include: o Conservation o Pumping allocations o Well location restrictions Projects and Management Actions Questions? 31 32 More Information •ECC GSP Plan: https://www.eccc-irwm.org/sgma-documents-reports •Email: groundwaterinfo@dcd.cccounty.us TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE 7. Meeting Date:11/08/2021   Subject:RECEIVE the status report on the Letter of Understanding (LOU) for maintenance of PG&E streetlights in Contra Costa County & MONITOR implementation. Submitted For: TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE,  Department:Conservation & Development Referral No.: 14   Referral Name: RECEIVE annual report on the Letter of Understanding with PG&E for the maintenance of PG&E street lights in Contra Costa County.  Presenter: Rochelle Johnson, Department of Public Works Contact: Rochelle Johnson (925)313-2299 Referral History: The Transportation, Water and Infrastructure Committee (TWIC) accepted the 2020 status report regarding the coordination between Cities (Countywide) and PG&E on October 12, 2020. A supplemental report was presented on December 14, 2020. Referral Update: The TWIC requested that Public Works management report annually on the status of street light maintenance coordination efforts with PG&E. Management last reported to the TWIC on October 12, 2020, regarding this item.  Background:  The Letter of Understanding (LOU) dated February 2008, between PG&E and the County, states the commitment of PG&E for open communication, responsive service levels, and actions in resolving issues related to street light performance. Over the past two years, Public Works management has worked with PG&E management to revise the LOU to address current service levels. As of February 25, 2021, Public Works staff is pleased to report that a signed LOU has been received from PG&E. Both Contra Costa County and PG&E will be monitoring service levels provided by PG&E and are prepared to reassess the LOU on a semi-annual basis and revise as needed.  A feature of the LOU is to maintain open communication channels. This is accomplished by conducting regular discussions at Street Light Coordination meetings which include the County, its constituents, and Cities and Towns.  Since the last report period, the Coordination meetings have convened once per quarter. These meetings have included regular attendance by participating agencies. In response to the needs of participating agencies amid the pandemic, the meetings have been hosted by the County via Zoom. Meeting using this platform has been a convenience to participating agencies and also allowed opportunities to review effective practices throughout the County. As agencies move beyond the pandemic, we anticipate that in-person meetings will resume. County staff continually polls Cities and Towns for presentation topics of interest. To date, meeting topics have included: • Decorative LED program and rates for energy use; • Street lights and pole maintenance, wire theft, pole knockdowns and graffiti; • Decorative LED lighting program; • Advanced controls; • Portal service planning ; • Small cell sites; • Letter of Understanding (LOU) Revision Review; and • Improving inventory records management. To support PG&E in addressing related matters, the County has established a relationship with the California Street Light Association (CAL-SLA). This organization has maintained a continued relationship to support the needs of Coordination Meeting Participants. In preparation for this report, Cities and Towns were invited to report any service level concerns. Reported feedback was generally positive with City, Town, and County staff stating that PG&E responsiveness was consistent with the LOU.  PG&E has stated that services levels should continue to improve once Salesforce support is incorporated into their services.  There is an ongoing request for PG&E to provide participating agencies with GIS data of streetlights. The intention of this request is to mitigate inventory and billing discrepancies. PG&E has stated that they are not able to provide this data as the costs are excessive, and that it is anticipated that the implementation of Salesforce should help cleanup inventory and billing discrepancies.  Details of the PG&E billing structure are described in the Electric Schedule, approved by the Public Utilities Commission (PUC) and provided by PG&E. The most recent version is effective March 2021. We have recently learned that the guiding language for determining the responsible party for lights meeting the LS1E criteria inconsistently applied by PG&E. We have confirmed with CAL-SLA, that streetlights identified as LS1E should be maintained by PG&E. Staff will continue to monitor this issue and other issues related to billing and inventory and report findings to the TWIC. The Cities, Towns, and County will continue to monitor overall service levels as detailed in the LOU as well as service needs that at present that have not been included in the LOU. Should it be deemed appropriate, those service needs will be included in future iterations of the LOU. Recommendation(s)/Next Step(s): RECIEVE and COMMENT on the status report on the street light service coordination effort RECIEVE and COMMENT on the status report on the street light service coordination effort between PG&E and the County Public Works Department and Cities for street light maintenance. Fiscal Impact (if any): None. All costs for street lights are funded by County Service Area L-100 and Community Facility District 2010-1. Attachments BO-LOU with PG&E streetlights 4-8-08 Rate Schedule LS1 - PG&E owned lights PGE LOU 2021FINAL_signed U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45482-E Cancelling Revised Cal. P.U.C. Sheet No. 26965-E ELECTRIC SCHEDULE LS-1 Sheet 1 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution APPLICABILITY: This schedule is applicable to PG&E-owned and maintained lighting installations which illuminate streets, highways, and other outdoor ways and places and which generally utilize PG&E’s distribution facilities under the provisions contained b elow. Rates of Class A through Class F service will be applicable as determined in Special Condition 4. TERRITORY: The entire territory served. RATES: The total monthly charge per lamp is equal to the sum of the facility charge and the energy charge. The monthly charge per lamp used for billing is calculated using unrounded facility and energy charges. Monthly facility charges include the costs of owning, operating and maintaining the various facilities for each Schedule LS-1 Class. Monthly energy charges are based on the kWh usage of each lamp. Monthly energy charges per lamp are calculated using the following formula: (Lamp wattage + ballast wattage) x 4,100 hours/12 months/1000 x streetlight energy rate per kilowatt hour (kWh). Ballast wattage = ballast factor x lamp wattage. Total bundled monthly facility and energy charges are shown below. The various ballast wattages used in the monthly energy charge calculations can be found in the Ballast Factor table following the monthly energy charges. Ballast factors are averaged within each grouping (range of wattages). The same ballast factor is applied to all of the lamps that fall within its watt range. Applicant or Customer must provide third party documentation where manufacturer’s information is not available for rated wattage consumption before PG&E will accept lamps for this schedule. Direct Access (DA) and Community Choice Aggregation (CCA) charges shall be calculated in accordance with Condition 17, Billing, below. (T) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 49138-E Cancelling Revised Cal. P.U.C. Sheet No. 48227-E ELECTRIC SCHEDULE LS-1 Sheet 2 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 6090-E-A Issued by Submitted February 26, 2021 Decision Robert S. Kenney Effective March 1, 2021 Vice President, Regulatory Affairs Resolution RATES: (Cont’d.) Facilities Charge Per Lamp Per Month CLASS A B C** D E F $6.849 $7.126 $6.680 $9.331 $9.664 $7.828 LED Program Incremental Facility Charge $0.000 $0.000 $12.768 $0.000 $0.000 Energy Charge Per Lamp Per Month All Night Rates LAMP WATTS kWh per MONTH AVERAGE INITIAL LUMENS All Night Rate Half-Hour Adjustment INCANDESCENTLAMPS*: 58 20 600 $3.751 (I) $0.171 (I) 92 31 1,000 $5.814 (I) $0.264 (I) 189 65 2,500 $12.190 (I) $0.554 (I) 295 101 4,000 $18.942 (I) $0.861 (I) 405 139 6,000 $26.068 (I) $1.185 (I) MERCURYVAPORLAMPS*: 100 40 3,500 $7.502 (I) $0.341 (I) 175 68 7,500 $12.753 (I) $0.580 (I) 250 97 11,000 $18.191 (I) $0.827 (I) 400 152 21,000 $28.506 (I) $1.296 (I) 700 266 37,000 $49.886 (I) $2.268 (I) HIGHPRESSURESODIUMVAPORLAMPS***: 120 Volts 70 29 5,800 $5.439 (I) $0.247 (I) 100 41 9,500 $7.689 (I) $0.350 (I) 150 60 16,000 $11.252 (I) $0.511 (I) 200 80 22,000 $15.003 (I) $0.682 (I) 250 100 26,000 $18.754 (I) $0.852 (I) 400 154 46,000 $28.881 (I) $1.313 (I) 240 Volts 70 34 5,800 $6.376 (I) $0.290 (I) 100 47 9,500 $8.814 (I) $0.401 (I) 150 69 16,000 $12.940 (I) $0.588 (I) 200 81 22,000 $15.191 (I) $0.691 (I) 250 100 25,500 $18.754 (I) $0.852 (I) 400 154 46,000 $28.881 (I) $1.313 (I) _______________ * Closed to new installations per Advice 669-E, effective June 8, 1978. ** Closed to new mixed ownership installations. See Special Condition 4. *** Closed to new installations for all Classes except D per Advice 5652-E U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45484-E Cancelling Revised Cal. P.U.C. Sheet No. 26967-E* ELECTRIC SCHEDULE LS-1 Sheet 3 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution RATES: (Cont’d.) Ballast Factors by Lamp Type and Watt Range Watt Range Ballast Factor Watt Range Ballast Factor MERCURY VAPOR* (T) HIGH PRESSURE SODIUM VAPOR** (T) 1 to 75 31.00% 76 to 125 17.07% 120 Volts 126 to 325 13.69% 1 to 40 25.44% 326 to 800 11.22% 41 to 60 22.93% 801 + 10.34% 61 to 85 21.25% 86 to 125 20.00% (D) 126 + 17.07% | | 240 Volts | 1 to 60 40.49% | 61 to 85 42.16% (D) 86 to 125 37.56% 126 to 175 34.63% METAL HALIDE 176 to 225 18.54% 1 to 85 25.44% 226 to 280 17.07% 86 to 200 20.39% 281 to 380 12.35% 201 to 375 22.93% 381 + 12.68% 376 to 700 18.54% 701 + 13.27% _______________ * Closed to new installations per Advice 669-E effective June 8, 1978 ** Closed to new installations, except for Class D per Advice 5652-E. (T) (T) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 49139-E Cancelling Revised Cal. P.U.C. Sheet No. 48228-E ELECTRIC SCHEDULE LS-1 Sheet 4 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 6090-E-A Issued by Submitted February 26, 2021 Decision Robert S. Kenney Effective March 1, 2021 Vice President, Regulatory Affairs Resolution RATES: (Cont’d.) LIGHT-EMITTING DIODE (LED) LAMPS: 120-240 VOLTS Nominal Lamp Ratings LAMP WATTS*** kWh per MONTH**** A, C, D, E and F Only Energy Rates Per Lamp Per Month Half-Hour Adjustment 0.0-5.0 0.9 $0.169 (I) $0.008 5.1-10.0 2.6 $0.488 (I) $0.022 10.1-15.0 4.3 $0.806 (I) $0.037 (I) 15.1-20.0 6.0 $1.125 (I) $0.051 (I) 20.1-25.0 7.7 $1.444 (I) $0.066 (I) 25.1-30.0 9.4 $1.763 (I) $0.080 (I) 30.1-35.0 11.1 $2.082 (I) $0.095 (I) 35.1-40.0 12.8 $2.401 (I) $0.109 (I) 40.1-45.0 14.5 $2.719 (I) $0.124 (I) 45.1-50.0 16.2 $3.038 (I) $0.138 (I) 50.1-55.0 17.9 $3.357 (I) $0.153 (I) 55.1-60.0 19.6 $3.676 (I) $0.167 (I) 60.1-65.0 21.4 $4.013 (I) $0.182 (I) 65.1-70.0 23.1 $4.332 (I) $0.197 (I) 70.1-75.0 24.8 $4.651 (I) $0.211 (I) 75.1-80.0 26.5 $4.970 (I) $0.226 (I) 80.1-85.0 28.2 $5.289 (I) $0.240 (I) 85.1-90.0 29.9 $5.607 (I) $0.255 (I) 90.1-95.0 31.6 $5.926 (I) $0.269 (I) *** Wattage based on total consumption of lamp and driver. **** Assumptions consistent with tariff, based on 4100 hours of operation for a full year; mid-point in range established by deducting 2.5 watts from highest wattage in range. The energy use calculation is: (high wattage in range-2.5 watts)x( 4,100 hours/12 months/1000) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 49140-E Cancelling Revised Cal. P.U.C. Sheet No. 48229-E ELECTRIC SCHEDULE LS-1 Sheet 5 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 6090-E-A Issued by Submitted February 26, 2021 Decision Robert S. Kenney Effective March 1, 2021 Vice President, Regulatory Affairs Resolution RATES: (Cont’d.) LIGHT EMITTING DIODE (LED) LAMPS: 120-240 VOLTS (Cont’d.) Nominal Lamp Ratings LAMP WATTS*** kWh per MONTH**** A, C, D, E and F Only Energy Rates Per Lamp Per Month Half-Hour Adjustment 95.1-100.0 33.3 $6.245 (I) $0.284 (I) 100.1-105.1 35.0 $6.564 (I) $0.298 (I) 105.1-110.0 36.7 $6.883 (I) $0.313 (I) 110.1-115.0 38.4 $7.202 (I) $0.327 (I) 115.1-120.0 40.1 $7.520 (I) $0.342 (I) 120.1-125.0 41.9 $7.858 (I) $0.357 (I) 125.1-130.0 43.6 $8.177 (I) $0.372 (I) 130.1-135.0 45.3 $8.496 (I) $0.386 (I) 135.1-140.0 47.0 $8.814 (I) $0.401 (I) 140.1-145.0 48.7 $9.133 (I) $0.415 (I) 145.1-150.0 50.4 $9.452 (I) $0.430 (I) 150.1-155.0 52.1 $9.771 (I) $0.444 (I) 155.1-160.0 53.8 $10.090 (I) $0.459 (I) _________________________________ *** Wattage based on total consumption of lamp and driver. **** Assumptions consistent with tariff, based on 4100 hours of operation for a full year; mid-point in range established by deducting 2.5 watts from highest wattage in range. The energy use calculation is: (high wattage in range-2.5 watts)x( 4,100 hours/12 months/1000) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 49141-E Cancelling Revised Cal. P.U.C. Sheet No. 48230-E ELECTRIC SCHEDULE LS-1 Sheet 6 PG&E -OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 6090-E-A Issued by Submitted February 26, 2021 Decision Robert S. Kenney Effective March 1, 2021 Vice President, Regulatory Affairs Resolution RATES: (Cont’d.) LIGHT-EMITTING DIODE (LED) LAMPS: 120-240 VOLTS (Cont’d.) Nominal Lamp Ratings LAMP WATTS*** kWh per MONTH**** A, C, D, E and F Only Energy Rates Per Lamp Per Month Half-Hour Adjustment 160.1-165.0 55.5 $10.408 (I) $0.473 (I) 165.1-170.0 57.2 $10.727 (I) $0.488 (I) 170.1-175.0 58.9 $11.046 (I) $0.502 (I) 175.1-180.0 60.6 $11.365 (I) $0.517 (I) 180.1-185.0 62.4 $11.702 (I) $0.532 (I) 185.1-190.0 64.1 $12.021 (I) $0.546 (I) 190.1-195.0 65.8 $12.340 (I) $0.561 (I) 195.1-200.0 67.5 $12.659 (I) $0.575 (I) 200.1-205.0 69.2 $12.978 (I) $0.590 (I) 205.1-210.0 70.9 $13.297 (I) $0.604 (I) 210.1-215.0 72.6 $13.615 (I) $0.619 (I) 215.1-220.0 74.3 $13.934 (I) $0.633 (I) 220.1-225.0 76.0 $14.253 (I) $0.648 (I) 225.1-230.0 77.7 $14.572 (I) $0.662 (I) 230.1-235.0 79.4 $14.891 (I) $0.677 (I) 235.1-240.0 81.1 $15.209 (I) $0.691 (I) 240.1-245.0 82.9 $15.547 (I) $0.707 (I) 245.1-250.0 84.6 $15.866 (I) $0.721 (I) ____________________ *** Wattage based on total consumption of lamp and driver. **** Assumptions c o nsistent with tariff, based on 4100 hours of oper ation for a full year; mid - point in range established by deducting 2.5 watts from highest wattage in range. The energy use calculation is: (high wattage in range-2.5 watts)x( 4,100 hours/12 months/1000) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 49142-E Cancelling Revised Cal. P.U.C. Sheet No. 48231-E ELECTRIC SCHEDULE LS-1 Sheet 7 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 6090-E-A Issued by Submitted February 26, 2021 Decision Robert S. Kenney Effective March 1, 2021 Vice President, Regulatory Affairs Resolution RATES: (Cont’d.) LIGHT-EMITTING DIODE (LED) LAMPS: 120-240 VOLTS (Cont’d.) Nominal Lamp Ratings LAMP WATTS*** kWh per MONTH**** A, C, D, E and F Only Energy Rates Per Lamp Per Month Half-Hour Adjustment 250.1-255.0 86.3 $16.185 (I) $0.736 (I) 255.1-260.0 88.0 $16.504 (I) $0.750 (I) 260.1-265.0 89.7 $16.822 (I) $0.765 (I) 265.1-270.0 91.4 $17.141 (I) $0.779 (I) 270.1-275.0 93.1 $17.460 (I) $0.794 (I) 275.1-280.0 94.8 $17.779 (I) $0.808 (I) 280.1-285.0 96.5 $18.098 (I) $0.823 (I) 285.1-290.0 98.2 $18.416 (I) $0.837 (I) 290.1-295.0 99.9 $18.735 (I) $0.852 (I) 295.1-300.0 101.6 $19.054 (I) $0.866 (I) 300.1-305.0 103.4 $19.392 (I) $0.881 (I) 305.1-310.0 105.1 $19.710 (I) $0.896 (I) 310.1-315.0 106.8 $20.029 (I) $0.910 (I) 315.1-320.0 108.5 $20.348 (I) $0.925 (I) 320.1-325.0 110.2 $20.667 (I) $0.939 (I) 325.1-330.0 111.9 $20.986 (I) $0.954 (I) __________________________ *** Wattage based on total consumption of lamp and driver. **** Assumptions consistent with tariff, based on 4100 hours of operation for a full year; mid-point in range established by deducting 2.5 watts from highest wattage in range. The energy use calculation is: (high wattage in range-2.5 watts)x( 4,100 hours/12 months/1000) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 49143-E Cancelling Revised Cal. P.U.C. Sheet No. 48232-E ELECTRIC SCHEDULE LS-1 Sheet 8 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 6090-E-A Issued by Submitted February 26, 2021 Decision Robert S. Kenney Effective March 1, 2021 Vice President, Regulatory Affairs Resolution RATES: (Cont’d.) LIGHT-EMITTING DIODE (LED) LAMPS: 120-240 VOLTS (Cont’d.) Nominal Lamp Ratings LAMP WATTS*** kWh per MONTH**** A, C, D, E and F Only Energy Rates Per Lamp Per Month Half-Hour Adjustment 330.1-335.0 113.6 $21.305 (I) $0.968 (I) 335.1-340.0 115.3 $21.623 (I) $0.983 (I) 340.1-345.0 117.0 $21.942 (I) $0.997 (I) 345.1-350.0 118.7 $22.261 (I) $1.012 (I) 350.1-355.0 120.4 $22.580 (I) $1.026 (I) 355.1-360.0 122.1 $22.899 (I) $1.041 (I) 360.1-365.0 123.9 $23.236 (I) $1.056 (I) 365.1-370.0 125.6 $23.555 (I) $1.071 (I) 370.1-375.0 127.3 $23.874 (I) $1.085 (I) 375.1-380.0 129.0 $24.193 (I) $1.100 (I) 380.1-385.0 130.7 $24.511 (I) $1.114 (I) 385.1-390.0 132.4 $24.830 (I) $1.129 (I) 390.1-395.0 134.1 $25.149 (I) $1.143 (I) 395.0-400.0 135.8 $25.468 (I) $1.158 (I) _______________________ *** Wattage based on total consumption of lamp and driver. **** Assumptions consistent with tariff, based on 4100 hours of operation for a full year; mid-point in range established by deducting 2.5 watts from highest wattage in range. The energy use calculation is: (high wattage in range-2.5 watts)x( 4,100 hours/12 months/1000) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 49144-E Cancelling Revised Cal. P.U.C. Sheet No. 48233-E ELECTRIC SCHEDULE LS-1 Sheet 9 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 6090-E-A Issued by Submitted February 26, 2021 Decision Robert S. Kenney Effective March 1, 2021 Vice President, Regulatory Affairs Resolution RATES: (Cont’d.) TOTAL ENERGY RATES Total Energy Charge Rate ($ per kWh) $0.18754 (I) UNBUNDLING OF TOTAL ENERGY CHARGES The total energy charge is unbundled according to the component rates shown below. Energy Rate by Components ($ per kWh) Generation $0.09091 (I) Distribution** $0.05985 (I) Transmission* $0.02377 Transmission Rate Adjustments* (all usage) ($0.00248) (R) Reliability Services* $0.00011 Public Purpose Programs $0.00532 (I) Nuclear Decommissioning $0.00093 Competition Transition Charge $0.00003 Energy Cost Recovery Amount $0.00032 Wildfire Fund Charge $0.00580 New System Generation Charge $0.00298 _________ * Transmission, Transmission Rate Adjustments, and Reliability Service charges are combined for presentation on customer bills. ** Distribution and New System Generation Charges are combined for presentation on customer bills. U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45485-E Cancelling Revised Cal. P.U.C. Sheet No. 30278-E ELECTRIC SCHEDULE LS-1 Sheet 10 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution MORE THAN ONE LIGHT ON A POLE: Where more than one light with a single Customer of Record is installed on a pole, all lights other than the first will be billed on the Class C rate. Not applicable to installations made prior to September 11, 1978. (T) SPECIAL CONDITIONS: 1. TYPE OF SERVICE: (a) PG&E provides basic lighting services with limited standard facilities, pole types and configurations. Only equipment in PG&E’s current standards are eligible for installation under LS-1, except as addressed in Special Condition 12. Current standards are available through PG&E’s Service Planning application process; (b) Applicant or Customer is responsible for lighting pattern layout and coverage for safety considerations; and (c) PG&E reserves the right to supply either “multiple” or “series” service. Series service to new lights will only be made where it is practical from PG&E's engineering standpoint to supply them from existing series systems. 2. ANNUAL OPERATING SCHEDULE: The above rates for All-Night (AN) service assume an average of approximately 11 hours operation per night and apply to lamps which will be turned on and off once each night in accordance with a regular operating schedule agreeable to the Customer but not exceeding 4,100 hours per year. This is also predicated on an electronic type photo control meeting ANSI standard C.136.10, with a turn on value of 1.0 footcandles and turn off value of 1.5 foot candles. Electro mechanical or thermal type photo controls are not acceptable for this rate schedule. 3. OPERATING SCHEDULES OTHER THAN ALL-NIGHT: Rates for regular operating schedules other than full AN will be the AN rate plus or minus, respectively, the half-hour adjustment for each half-hour more or less than an average of approximately 11 hours per night. This adjustment will apply only to lamps on regular operating schedules of not less than 1,095 hours per year, or three hours per night, and may be applied for 24-hour operation. (T) | | (T) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45486-E Cancelling Revised Cal. P.U.C. Sheet No. 43850-E ELECTRIC SCHEDULE LS-1 Sheet 11 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution SPECIAL CONDITIONS: (Cont’d) 4. DESCRIPTION OF SERVICE PROVIDED: The following describes lighting facilities only. Service connection and lighting installation responsibilities and payments, are described in special conditions 7, 8 and 9. PG&E provides several Classes (A, B, C, D, E and F) of LS-1 facilities. The Classes enable fair distribution of facility charges in correlation with PG&E’s cost to maintain each Class. Once installed, PG&E maintains full ownership and maintenance responsibility for all Classes of LS-1. Only equipment included in PG&E’s current standards are eligible for installation under LS-1, except as addressed in Special Condition 12. Current standards are available through PG&E’s Service Planning application process. Class A: Applicable to standard non-decorative luminaires installed on a PG&E distribution pole for illumination of public and private ways. PG&E provides its standard luminaire, control facility, and standard 30” support arm on its existing distribution pole. There is no installation charge for this Class for standard (non-decorative) LED luminaires. Class B: Closed to new installations per Advice 688-E, effective September 11, 1978. This Class is for streetlight installations for which the Customer has paid the estimated installed cost of the luminaire, support arm and control facilities. (T) (T) (N) | | | | | | | | (N) (T) | | | | | | | | | | | (T) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45487-E Cancelling Revised Cal. P.U.C. Sheet No. 35445-E ELECTRIC SCHEDULE LS-1 Sheet 12 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution SPECIAL CONDITIONS: (Cont’d) 4. DESCRIPTION OF SERVICE PROVIDED: (Cont’d.) Class C: Closed to new mixed ownership installations as of March 1, 2006 per Advice 2791-E in compliance with Decision 05-11-005. New Class C installations are applicable to an individual Customer’s second or additional luminaire(s) on a PG&E owned pole. The Class considers that facility charges for the pole are paid through the primary luminaire which is under Class A, D, E or F. PG&E provides its standard luminaire, control facility and a standard 30” bracket if applicable. Customer is responsible for all further costs, see Special Condition 9. For LS-1C fixtures placed in operation prior to March 1, 2006, the customer owns and is responsible to maintain the pole, it’s foundation and any support brackets. PG&E owns and maintains all other components Class D: Applicable to decorative street light fixtures. PG&E provides its standard post top or pendant style fixture and control facility. Customer is responsible for all further costs, see Special Condition 9. Class E: Applicable to street light only poles on a concrete foundation, installed solely for the luminaire. PG&E provides a standard luminaire, control facility and service connection. Customer is responsible for all further costs, see Special Condition 9. Class F: Applicable to embedded street light only poles, installed solely for the luminaire. PG&E provides a standard luminaire, control facility, a standard 30” bracket if applicable. and service connection. Customer is responsible for all further costs, see Special Condition 9. (T) | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | (T) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45488-E Cancelling Revised Cal. P.U.C. Sheet No. 30281-E ELECTRIC SCHEDULE LS-1 Sheet 13 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution SPECIAL CONDITIONS: (Cont’d.) 5. REARRANGEMENT OF FACILITIES: For any relocation, or rearrangement of PG&E’s existing streetlight or service facilities at the request of the Customer and agreed to by PG&E, Customer shall pay PG&E, in advance, PG&E’s estimated total cost of the relocation or rearrangement. 6. SERVICE REQUESTS: Service requests shall be made through PG&E’s Service Planning organization and shall include form 79-1007 or 79-1008 for installations, removals, rearrangements, energizing and de-energizing of streetlight facilities. 7. SERVICE and LIGHTING INSTALLATION RESPONSIBILITIES: The Applicant at its expense shall perform all necessary trenching, backfill and paving, and shall furnish and install all necessary conduit, and substructures, including substructures for transformer installations if necessary, for street light service and circuits, in accordance with PG&E's specifications. Upon acceptance by PG&E, ownership of the conduit and substructures will automatically transfer to PG&E. Riser material is installed by PG&E at the Customer’s expense. Tree trimming is the responsibility of the Applicant. PG&E will furnish and install the underground or overhead service conductor, transformers and necessary facilities to complete the service from the distribution line source subject to the payment provision of special condition 8. PG&E will establish service delivery points in close proximity to its distribution system as follows: (T) | | (T) U 39 San Francisco, California Original Cal. P.U.C. Sheet No. 30282-E ELECTRIC SCHEDULE LS-1 Sheet 14 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 3831-E Issued by Date Filed April 18, 2011 Decision Jane K. Yura Effective June 1, 2011 Vice President Resolution Regulation and Rates SPECIAL CONDITIONS: (Cont’d.) 7. SERVICE and LIGHTING INSTALLATION RESPONSIBILITIES (Cont’d.) OVERHEAD: a) In an overhead area - a single drop will be installed; b) for an overhead to underground system, service will be established in a PG&E box at the base of the pole, or directly to a single light or to the first light of a multiple circuit based on PG&E’s standard design, in the shortest most practical configuration from the connection on the distribution line source. UNDERGROUND: For an underground area, service will be established at the nearest existing secondary box. Where no secondary facilities exist, a new service, transformer and secondary splice box, as required, will be installed in the shortest most practical configuration from the connection on the distribution line source. The Customer shall provide rights of way, clear route and access acceptable to PG&E in accordance with the provisions of Electric Rule 16, and Special Condition 11 below. Line or service extensions not conforming to the foregoing descriptions shall be installed under Special Condition 13. (N) (N) (N) (L) I I I I I I I I I I I I I I I I I I I I I (L) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 30283-E Cancelling Revised Cal. P.U.C. Sheet No. 26971-E ELECTRIC SCHEDULE LS-1 Sheet 15 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 3831-E Issued by Date Filed April 18, 2011 Decision Jane K. Yura Effective June 1, 2011 Vice President Resolution Regulation and Rates SPECIAL CONDITIONS: (Cont’d.) 8. NON REFUNDABLE PAYMENT FOR SERVICE POINT INSTALLATION a) The Applicant shall pay in advance the estimated installed cost of facilities necessary to establish a service delivery point to serve the street light or street light circuit, minus a one-time revenue allowance based on the kWh of energy usage and the distribution component of the energy rate posted in the rate schedule for the lamps installed. The total allowance shall be determined by taking the annual equivalent kWh multiplied by the distribution component, then divided by the cost of service factor used in electric Rule 15.C. b) The allowance may only be provided where PG&E must install service facilities to connect street lights or street light circuits. No allowance will be provided where a simple connection is required, or in the case of a Class A installation. Only lights operating at a minimum on the full 11hour AN schedule shall be granted allowances. Where Applicant received allowances based upon 11 hour AN operation, no billing adjustments, as otherwise provided for in Special Condition 3, shall be made for the first three (3) years following commencement of service. (L) I I I I I I I I I I I I I I I I I I I I I I I I I (L) (L) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45489-E Cancelling Revised Cal. P.U.C. Sheet No. 43851-E ELECTRIC SCHEDULE LS-1 Sheet 16 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution SPECIAL CONDITIONS: (Cont’d.) 9. PAYMENT FOR INSTALLATION OF LIGHTING FACILITIES: See Special Condition 4 for a description of what material PG&E provides for each LS-1 Class (A, B, C, D, E and F). The Customer is responsible for the cost of all additional materials required to complete the installation. Only equipment included in PG&E’s current standards are eligible for installation under LS-1, except as addressed in Special Condition 12. Current standards are available through PG&E’s Service Planning application process. Class A: Unless rearrangement of facilities is required to enable installation, there is no installation charge for this class for standard luminaires. Class B: This Class is closed for new installations. Class C: Effective March 1, 2006, this Class is restricted to new fixtures installed on PG&E owned distribution or streetlight only poles on which the Customer has an existing streetlight installed under another LS-1 Class (A, D, E or F). Customer or Applicant shall pay, in advance, the estimated installed cost of the remaining lighting facilities that PG&E is required to install. Allowances are not applied to street light facilities on the load side of the service delivery point. (D) | | (D) (N) | | | | | | | | | | | | | | | | | | | | | | (N) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45490-E ELECTRIC SCHEDULE LS-1 Sheet 17 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution SPECIAL CONDITIONS: (Cont’d.) 9. PAYMENT FOR INSTALLATION OF LIGHTING FACILITIES (Cont’d.): Class D: Restricted to Decorative Fixtures - Customer or Applicant shall pay, in advance, the estimated installed cost of the remaining lighting facilities that PG&E is required to install. Allowances are not applied to street light facilities on the load side of the service delivery point. For new Class D installations where the Customer requests an LED luminaire, the Customer may choose to pay to PG&E in advance, a non-refundable amount equal to PG&E’s estimated cost difference between the selected LED fixture and PG&E’s most similar HPSV fixture as determined by PG&E. Customers not wishing to pay the estimated cost difference between LED and HPSV for new lighting installations under LS-1D may elect to include new lights under PG&E’s optional LED streetlight replacement program by choosing to pay the Incremental Facility Charge for LS-1D as shown on Sheet 2 of this schedule. LS-1D Customers with existing HPSV fixtures who prefer to not pay the up-front cost for replacement LED fixtures may also elect to participate in PG&E’s optional LED streetlight replacement program by choosing to pay the LS-1D Incremental Facility Charge as shown on Sheet 2. Customers electing to participate in PG&E’s optional LED streetlight replacement program will be eligible for any applicable rebate or incentive available through ratepayer-funded programs intended to increase energy efficiency. Classes E and F: Customer or Applicant shall pay, in advance, the estimated installed cost of the remaining lighting facilities that PG&E is required to install. Allowances are not applied to street light facilities on the load side of the service delivery point. (N) | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | (N) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45491-E Cancelling Revised Cal. P.U.C. Sheet No. 43852-E ELECTRIC SCHEDULE LS-1 Sheet 18 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution SPECIAL CONDITIONS: (Cont’d.) 10. OWNERSHIP: All facilities installed under the provisions of this rate schedule shall be owned, operated and maintained by PG&E. 11. MAINTENANCE, ACCESS, CLEARANCES and ATTACHMENTS a) Maintenance: PG&E shall exercise reasonable care and diligence in maintaining PG&E-owned facilities. For PG&E’s operational efficiency, maintenance and restoration activities may be completed with like for like lighting technology or, at PG&E’s discretion may include updating to PG&E’s current lighting technology at no incremental cost to the Customer . b) Access: The Customer is responsible for maintaining adequate access for PG&E’s standard equipment used in maintaining facilities and for installation of its facilities. PG&E reserves the right to collect additional maintenance costs due to obstructed access or other conditions preventing PG&E from maintaining its equipment with standard operating procedures. Applicant or Customer shall be responsible for rearrangement charges as provided for in Special Condition 5. c) Clearances: The Customer will, at their own expense, correct all access or clearance infractions, or pay PG&E's total estimated cost for PG&E to relocate facilities to a new location which is acceptable to PG&E. Failure to comply with corrective measures within a reasonable time may result in discontinuance of service in accordance with electric Rule 11. Applicant or Customer shall be responsible for managing vegetation to maintain lighting patterns, required clearances and access for maintenance of existing poles and luminaires. d) Attachments: Any attachments to street light poles requested by governmental agencies requires prior approval by PG&E and execution of a license agreement. Unauthorized attachments are subject to removal. (L) | | | | | | | (L) (L)(N) (N) | | | (N) (L)(T) (L) | | | | | | (L) (T) (T) | (T) (N) | | (N) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45492-E Cancelling Revised Cal. P.U.C. Sheet No. 35448-E ELECTRIC SCHEDULE LS-1 Sheet 19 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution SPECIAL CONDITIONS: (Cont’d.) 12. SPECIAL EQUIPMENT: Luminaires, poles, posts and other equipment requested by an Applicant or Customer in addition to or in substitution for PG&E's standard poles, posts, photo controls and equipment, will be provided if such equipment meets PG&E's engineering and operating standards, and if PG&E agrees to do so, provided that the Applicant or Customer pays the cost difference between the equipment normally installed by PG&E and the equipment requested by the Applicant or Customer, plus an additional Cost of Ownership payment as provided for in Section I.3 of electric Rule 2. This provision is also applicable to other special hardware required or requested by the Applicant or Customer or any governmental agency having jurisdiction. 13. LINE EXTENSIONS A. Where PG&E extends its facilities to street light installations in advance of subdivision projects where subdivision maps have been approved by local authorities, extensions will be installed under the provisions of electric Rule 15, except as noted below. B. Where PG&E extends its facilities to street light installations in the absence of any approved subdivision maps, applicant shall pay PG&E’s estimated cost, plus cost of ownership and applicable tax. Standard form contract 62-4527, Agreement to Perform Tariff Schedule Related Work, shall be used for these installations. (L) | | | | | | | | (L) (L)(D) (L) | | | | | | | | | | | | | | | | (L) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 45493-E Cancelling Revised Cal. P.U.C. Sheet No. 40905-E ELECTRIC SCHEDULE LS-1 Sheet 20 PG&E-OWNED STREET AND HIGHWAY LIGHTING (Continued) Advice 5652-E Issued by Submitted October 3, 2019 Decision Robert S. Kenney Effective November 2, 2019 Vice President, Regulatory Affairs Resolution SPECIAL CONDITIONS: (Cont’d.) 14. TEMPORARY DISCOUNTINUANCE OF SERVICE: (Fixture remains in place.) At the request of the Customer, PG&E will temporarily discontinue service to the individual luminaires provided the Customer continues to pay the applicable facility charges and any applicable taxes for the Class of Service as identified in the Rates scection of this Schedule, plus the estimated cost to disconnect and reconnect the light. Upon Customer request for re-energization, PG&E may update the fixtures to current standards 15. CONTRACT: Except as otherwise provided in this rate schedule, or where lighting service is installed in conjunction with facilities installed under the provisions of Rules 15 or 16, standard form contract 62-4527, Agreement to Perform Tariff Schedule Related Work shall be used for installations, rearrangements or relocations. 16. MINIMUM SERVICE PERIOD: Temporary services will be installed under electric Rule 13. 17. BILLING: A Customer’s bill is calculated based on the option applicable to the Customer. Payment will be made in accordance with PG&E’s filed tariffs. Bundled Service Customers receive supply and delivery service solely from PG&E. The customer’s bill is based on the Total Rates and Conditions set forth in this schedule. Transitional Bundled Service Customers take transitional bundled service as prescribed in Rules 22.1 and 23, or take bundled service prior to the end of the six (6) month advance notice period required to elect bundled portfolio service as prescribed in Rules 22.1 and 23. These customers shall pay charges for transmission, transmission rate adjustments, reliability services, distribution, nuclear decommissioning, public purpose programs, New System Generation Charges, the applicable Cost Responsibility Surcharge (CRS) pursuant to Schedule DA CRS or Schedule CCA CRS, and short-term commodity prices as set forth in Schedule TBCC. (L) | (L) (L)(T) | (L)(T) (L)(N) (N) (N) (L) | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | (L) U 39 San Francisco, California Revised Cal. P.U.C. Sheet No. 49145-E Cancelling Revised Cal. P.U.C. Sheet No. 48234-E ELECTRIC SCHEDULE LS-1 Sheet 21 PG&E -OWNED STREET AND HIGHWAY LIGHTING Advice 6090-E-A Issued by Submitted February 26, 2021 Decision Robert S. Kenney Effective March 1, 2021 Vice President, Regulatory Affairs Resolution SPECIAL CONDITIONS: (Cont’d.) 17. BILLING (Cont’d.): Direct Access (DA) and Community Choice Aggregation (CCA) Customers purchase energy from their non-utility provider and continue receiving delivery services from PG&E. Bills are equal to the sum of charges for transmission, transmission rate adjustments, reliability services, distribution, public purpose programs, nuclear decommissioning, New System Generation Charges, the franchise fee surcharge, and the applicable CRS. The CRS is equal to the sum of t he individual charges set forth below. Exemptions to the CRS are set forth in Schedules DA CRS and CCA CRS. DA / CCA CRS Energy Cost Recovery Amount Charge (per kWh) $0.00032 Wildfire Fund Charge (per kWh) $0.00580 CTC Charge (per kWh) $0.00003 Power Charge Indifference Adjustment (per kWh) 2009 Vintage $0.02796 (I) 2010 Vintage $0.03367 (I) 2011 Vintage $0.03518 (I) 2012 Vintage $0.03725 (I) 2013 Vintage $0.03743 (I) 2014 Vintage $0.03746 (I) 2015 Vintage $0.03763 (I) 2016 Vintage $0.03788 (I) 2017 Vintage $0.03791 (I) 2018 Vintage $0.03748 (I) 2019 Vintage $0.02854 (I) 2020 Vintage $0.02300 (I) 2021 Vintage $0.02300 (I) 18. WILDFIRE FUND CHARGE : Th e Wildfire Fund Charge was imposed by California Public Utilities Commission Decisi ons 19-10-056, 20-07-014, 20-09-005, and 20-09-023 and is property of Department of Water Resources (DWR) for all purposes under California law. The Charge became effective October 1, 2020, and applies to all retail sales, excluding CARE and Medical Basel ine sales. The Wildfire Fund Charge (where applicable) is included in customers’ total billed amounts. The Wildfire Fund Charge replaces the DWR Bond Charge imposed by California Public Utilities Co mmission Decisions 02-10-063 and 02-12-082. PGE LOU 2021 Revision FINAL.docx Street Light Service Level Commitment To Contra Costa County [2021] PG&E is committed to delivering a high level of service to street light customers and providing features which enhance community safety. To ensure a high level of responsiveness to street light maintenance issues in Contra Costa County and the 19 Cities, PG&E is committed to the following (for street light facilities maintained by PG&E): 1) Reporting Street Light Problems and Tracking Results PG&E will continue to utilize its web based system where street light service requests and problems can be reported via an on-line request form. PG&E is committed to improving communication during this resolution process. The link for reporting streetlight outages and checking the status of street light outages is: http://www.pge.com/en/myhome/servicerequests/streetlights/single/index.pag. This will be updated as needed to reflect the most up to date reporting method. In addition, street light service requests can be reported through PG&E’s email address: streetlighttrouble@pge.com. This email address is monitored Monday - Friday, 630am - 330pm. For escalated streetlight requests outside of those hours, please report to 800-743-5000. Outages reports are acknowledged via automated email response when received, when case numbers are assigned, and when the street light service request work is completed or resolved. PG&E is committed to improving this system, and developing more robust on-line reporting and tracking systems that will serve to improve communication with all customers. PG&E will provide a one (1) page process flow chart for the resolution process to county staff upon availability. Upon providing this process, PG&E will clarify if email or web based platforms are preferred. *Note that the customer will receive an automated reply and within a few days a tracking number will be received 2) Responding to Street Light Outages a. Response to Reported Street Light Outages PG&E will respond, assess and complete repair of reported street light outages (burnouts) within 14 days of being notified of the outage. b. Outages Resulting from Poles that are "Knocked Down" Where a PG&E owned or maintained street light pole is "knocked down", PG&E will provide an immediate response to the "knock-down", secure the site, and make the situation safe to the public prior to leaving the site. PG&E will complete any remaining required repairs within 90 days. If PG&E, for any reason, will not be able to complete repairs within 90 days PG&E will notify the customer and will provide an estimated date of completion for repairs. If PG&E should become aware of a knocked down pole by customer call or staff inspection, they will notify the County. This will allow for transparency in service provision and improved customer support. PGE LOU 2021 Revision FINAL.docx c. Monthly Report PG&E will provide a monthly report to Contra Costa County which details the status of outages and knocked down poles. This report shall detail the resolution if the matter has not been resolved at the time of the report, the report shall include a proposed timeline and resolution. d. Credit Adjustment In the event that a customer is without service as a result of an inoperable street light beyond fourteen (14) business days, the customer shall notify their PG&E Local Customer Relationship Manager (LCRM) for a service credit. 3) Requesting Street Lights and Shields Installation PG&E will continue to utilize the Customer Connection Online web based system where street lights and shields installation can be reported via the on-line request form. The link for requesting street lights and shields installation is Customer Connections https://www.pge.com/en_US/small-medium-business/building-and- property/building-and-maintenance/building-and-renovation/manage-your- services.page?WT.mc_id=Vanity_CustomerConnections. Shields may also be requested by calling our Customer Connections’ telephone number (1-877-743-7782). PG&E will acknowledge these requests via automated email response when received by the New Business Service Planning representative. PG&E will continue communication of the planning and installation process status via email, provide an estimated date of completion, and inform the customer of the next steps including approval, and installation. Upon receipt of new installation applications, PG&E will contact the applicant within 1-3 business days to advise them of the result and next steps. Any contract information will be submitted via email or regular mail and any costs associated with the planning and installation will be included in the contract. PG&E will give 10 days to sign and return contract to initiate the installation process. The cost of installing any shield (front, back or cul-de-sac) will be forwarded to the customer and included in the provisions of the associated contract. 4) Pole Maintenance, Replacement, Painting, and Cleaning For street light poles that need painting, cleaning due to graffiti, or have rust staining, PG&E will accommodate requests based on the demand of the community. All requests can be forwarded to the email: streetlighttrouble@pge.com or by calling 1(800)743-5000. These services may include time and materials costs at PG&Es expense. PG&E will respond to an initial assessment of the request for street light graffiti removal within 14 days of being notified. Upon notification of painting or rust abatement service need, PG&E will complete the service within 180 days. In the event that there is not an established maintenance schedule, PG&E will provide information to County staff pertaining to pole viability and associated replacement plans on a case by case basis. Any additional devices attached to agency LS2 street light poles must be processed through Customer Connections’ to execute an unmetered pole contract agreement. All lights must have a badge number and lamp sticker that corresponds to PG&E records. PGE LOU 2021 Revision FINAL.docx 5) Billing Improvements PG&E will work with Contra Costa County to explore methods to improve billing and inventory procedures in order to help resolve discrepancies, if any. It is incumbent upon the agency to respond timely to PG&E requests for information such as receiving account number or Service Agreement Identification (SAID), removal/start/ or stop dates etc. It is the agency’s responsibility to inform PG&E of ANY changes to LS2A lights as they are not PG&E owned or maintained. If LS2A  Agency needs to inform PG&E date of power loss and billing will stop.  Agency needs to inform PG&E of the date of restoration and billing will re-start. IF LS1  Agency should inform PG&E of the issue and PG&E can investigate internally for approximate date of removal and restoration and correct billing to field activity. PLEASE NOTE ELECTRIC RULE 17.1 allowing PG&E to back date & bill correct up to 3 years only. https://www.pge.com/tariffs/assets/pdf/tariffbook/ELEC_RULES_17.1.pdf 6) Annual Inventory Update PG&E will make every effort to work with Contra Costa County and Cities to rectify billing conflicts on an on - going basis. This will include providing the agencies with streetlight individual billing data, on an as-needed basis, so that they can conduct their own internal reviews. PG&E will provide a report of what is actively billed. The agency can use the report to cross check against their own inventory and PG&E will make corrections based on their findings. For LS1, PG&E owned and maintained, PG&E will provide the spatial data annually. For LS2A, agency owned and maintained, the spatial data may be purchased through a 3rd party vendor or the agency can purchase through PG&E’s New Revenue Development (NRD) department. Please contact the Local Customer Relations Managers (LCRM) assigned to your agency. 7) On-going Communication and Reporting Quarterly Coordination Meetings As determined by the survey of participating Cities in 2015, PG&E will continue to participate in Quarterly Coordination Meetings in as long as the agenda includes maintenance and repairs of streetlights. On occasion, PG&E may be invited to present evolving and new technologies, features, and services. PG&E will maintain open communication and responsiveness in assisting the County to coordinate and plan for these meetings. TWIC Participation PG&Es Division Sr. Manager or representative of local leadership team or the subject matter expert, will attend the annual Transportation Water and Infrastructure (TWIC) meeting in October to join the County in providing an annual report on coordination efforts. PGE LOU 2021 Revision FINAL.docx 8) Staffing Updates To assist Contra Costa County staff in facilitating communication, PG&E will provide Contra Costa County with a list of key management representatives on an annual basis. Additionally, PG&E will provide an advisement of key staffing. ITEMS FOR FUTURE CONSIDERATION LED and Photocell Group Maintenance and Replacement Program PG&E will establish and perform a group assessment program for the newly converted to LED street lights and photocells by the end of 2026. The life expectancy for LED street lights is approximately 20 years (with warranty of 10 years) and for photocells is 5 years. When the replacement of existing LED infrastructure occurs, PG&E will work closely with Contra Costa County to provide information related to new product choices selected for characteristics related to improved energy efficiency and as technology evolves, reduced glare and control of upward directed light as they become available and are approved for use . PG&E will replace LED street lights as they fail. When group lamp replacements are performed, PG&E will also perform other maintenance work, such as testing and replacement of photocells (as required) and cleaning of glassware, reflector, or refractor. Additionally, PG&E will provide to the County any cleaning schedule available for glassware. Invoice and Billing PG&E will work with Contra Costa County to identify how to simplify invoicing and keep track of inventory in order to resolve issues such as inaccurate inventories and multiple billing. PG&E will address changes to the inventory to not only clarify and reorganize the current information—but to insure that new additions or removals are reflected in the billing documentation. County agrees to adhere to the LS2A rate schedule. ##END## This LOU is a good faith understanding between Contra Costa County, representing the 19 included cities and PG&E. Victor Baker Date Senior Manager – Diablo l North Bay l Sonoma Divisions Pacific Gas and Electric Company (PG&E) 2/25/2021 TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE 8. Meeting Date:11/08/2021   Subject:ACCEPT Final Vision Zero Report draft dated 10/2021 & DIRECT Public Works staff on behalf of the County to incorporate comments & present to the Board Submitted For: TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE,  Department:Conservation & Development Referral No.: 18   Referral Name: Review transportation plans & svcs for specific populations, incl but not limited to County Low Income Transportation Action Plan, Coordinated Human Svcs Transportation Plan for Bay Area, Priorities for Senior Mobility, Bay Point, & CCCounty ATSP  Presenter: Craig Standafer and Jerry Fahy, Department of Public Works Contact: Craig Standafer (925)313-2018 Referral History: Vision Zero was discussed at the October 9, 2017 TWIC meeting as part of a general legislative analysis. It was also discussed at the July 9, 2018 TWIC in the context of the County’s Complete Streets policy. Referral Update: Vision Zero is the mind-set that all fatal and serious injury collisions are preventable through a Safe Systems Approach. A Safe System approach addresses the five elements of a safe transportation system, which are safe road users, safe vehicles, safe speeds, safe roads, and post-crash care. Many municipalities throughout the country, the world, and locally, such as San Francisco and City of Fremont have started a Vision Zero program. The County began this endeavor as a response to a high fatality rate between 2015 and 2017. The CCTA is also developing a Vision Zero program on a higher level program whereas the County’s Vision Zero program focuses on unincorporated roadways. The Vision Zero Program will qualify as the County’s requirement for the Local Road Safety Program that all municipalities in California are required to fulfill to receive Highway Safety Improvement Program (HSIP) grant funding. The Public Works Department launched a Technical Advisory Committee (TAC), made up of representatives of County Public Health, the California Highway Patrol, the CCTA, 511.org, and bicycle advocates. Vision Zero is being managed by Transportation Engineering consultant, Fehr and Peers. This TAC met four times over the course of six months. The TAC produced two documents that are intended to be viewed as a single volume. The Systemic Safety Analysis Report (also called the SSAR), laid out the framework for where, when, and how crashes were occurring on the unincorporated roadways. This document was finalized and accepted by Caltrans. The less “engineering-heavy” Final Vision Zero Report contains some of the same information as the SSAR, but it is expanded to include an action plan for County Public Health, law enforcement, as well as Public Works. In August 2021, Public Works met with representatives of each supervisor district to introduce the Vision Zero project and to give notice that the public draft of the Final Vision Zero Report would soon be circulated. That draft was distributed in early October, and comments have been coming in. The Public Works Department, on behalf of the agencies that assisted in developing the report, plans to give a presentation at the first Board of Supervisor’s meeting in the month of February (date to be announced). At that time, additional comments will be requested for a two-week period. The final report will be introduced for acceptance by the Board under a consent item at the last meeting in the month of March (date to be announced). County acceptance of the report will be required by Summer 2022 in order for Public Works staff to be eligible to submit HSIP grant applications next year. Recommendation(s)/Next Step(s): ACCEPT the draft of the Final Vision Zero Report dated October 2021, and DIRECT Public Works staff, on behalf of the County, to incorporate comments and present to the full Board of Supervisors. Fiscal Impact (if any): There is no fiscal impact to adopting the report. Attachments Vision Zero Report October 2021 Prepared By Contra Costa County Vision Zero FINAL REPORT DRAFT - AS OF Statement of Protection of Data from Discovery and Admissions SECTION 148 OF TITLE 23, UNITED STATES CODE REPORTS DISCOVERY AND ADMISSION INTO EVIDENCE OF CERTAIN REPORTS, SURVEYS, AND INFORMATION — Notwithstanding any other provision of law, reports, surveys, schedules, lists, or data compiled or collected for any purpose relating to this section, shall not be subject to discovery or admitted into evidence in a Federal or State court proceeding or considered for other purposes in any action for damages arising from any occurrence at the location identified or addressed in the reports, surveys, schedules, lists, or other data. Caltrans SSARP Grant ID: SSARPL-5928(133) 2 Contra Costa County Vision Zero Action Plan Acknowledgements Contra Costa County Staff Monish Sen Public Works Senior Traffic Engineer Jerry Fahy Public Works Supervising Civil Engineer Mary Halle Public Works Senior Civil Engineer Jeff Valeros Public Works Associate Civil Engineer Craig Standafer Public Works Civil Engineer Kelly Kalfsbeek Public Works Community and Media Relations Manager Jamar Stamps Conservation and Development Senior Planner Technical Advisory Committee Colin Clarke Contra Costa Transportation Authority Kirsten Riker 511 Contra Costa Captain Ben Moser Contra Costa California Highway Patrol Commander Luz Gomez Building Healthy Communities Manager Contra Costa Health Services Department Dave Campbell Bike East Bay Fehr & Peers Team Meghan Mitman Ryan McClain Ashlee Takushi Terence Zhao 3Contra Costa County Vision Zero Action Plan List of Abbreviations ADA Americans with Disabilities Act AHSC Affordable Housing and Sustainable Communities program ATP Active Transportation Program CAV Connected and Autonomous Vehicle CBO Community-Based Ogranization CCTA Contra Costa Transportation Authority CHP California Highway Patrol CIP Capital Improvement Plan DUI Driving Under the Influence EMS Emergency Medical Services EPC Equity Priority Communities HIN High Injury Network ICP Integrated Connectivity Project ITS Intelligent Transportation Systems KSI Killed or Severely Injured LPI Leading Pedestrian Interval LRSP Local Roadway Safety Plan MTC Metropolitan Transportation Commission NHTSA National Highway Traffic Safety Administration OTS Office of Traffic Safety PHB Pedestrian Hybrid Beacon RIPA Rural Innovation Project Area RRFB Rectangular Rapid Flashing Beacon SRTS Safe Routes to School SSAR Systemic Safety Analysis Report TAC Technical Advisory Committee TCC Transformative Climate Communities program TOD Transit-Oriented Development 4 Contra Costa County Vision Zero Action Plan A pedestrian crossing equipped with a RRFB in downtown Rodeo 5Contra Costa County Vision Zero Action Plan 6 Contra Costa County Vision Zero Action Plan 16 20 38 Chapter 2: Vision and Guiding Principles Chapter 3: Collision History, Risk Factors, and Trends Chapter 4: Countermeasures 56 70 74 Chapter 5: Project Development Chapter 6: Safety Efforts and Programs Chapter 7: Funding 8 Chapter 1: Introduction TABLE OF CONTENTS 82 Chapter 8: Vision Zero Core Elements and the Action Plan 7Contra Costa County Vision Zero Action Plan CHAPTER 1 8 Contra Costa County Vision Zero Action Plan INTRODUCTION 9Contra Costa County Vision Zero Action Plan Contra Costa County is committed to prioritizing safety and decreasing traffic-related deaths and serious injuries on county-maintained roadways. To this end, it participated in the Systemic Safety Analysis Report Program (SSARP), initiated by Caltrans to help local agencies identify systemic and hot spot safety improvement projects by completing a system-wide, multi-year, data-driven analysis of collision data. Between the study years of 2014 and 2018, 2,256 collisions occurred in unincorporated Contra Costa County that resulted in injuries. The number of annual collisions increased by 18%, with collisions resulting in someone being killed or severely injured (KSI) reaching a peak in 2018. The engineering- focused recommendations in the SSAR are a key step forward in curbing the rise in KSI collisions. The SSAR also presents a High Injury Network (HIN) for the County, laying the framework for the development of 11 collision profiles and 35 project locations. A list of top 10 priority projects were selected from the project locations list based on feedback from the community (via an interactive webmap) and from the Technical Advisory Committee (TAC) members. The TAC provided feedback to the project team throughout the SSAR and Vision Zero Plan process. The SSAR identified safety improvement opportunities for all modes of travel through roadway design projects that are relevant to project locations, feasible for implementation, and competitive for grant funding. Additional information from the SSAR can be found in Chapter 4 of this plan. This Vision Zero Plan builds upon the infrastructure- focused work of the SSAR to provide a comprehensive safety strategy for the County that includes a multidisciplinary, holistic approach to safety. Proven countermeasures that are competitive for grant funding are identified and can be implemented through the current and future Capital Improvement Plan (CIP) and key partnerships with safety stakeholders. This section defines the Safe System approach, explains the philosophy underpinning this Vision Zero plan, and provides background on safety work in the County. The Safe System Approach People are killed and seriously injured each day on roads in California and across the U.S. On average, a KSI collision occurs on county roadways once every week. Crashes can irreversibly change the course of human lives, touching victims, their families and loved ones, and society as a whole. Contra Costa County believes all KSIs are unacceptable and 10 Contra Costa County Vision Zero Action Plan is adopting a Safe System approach to improve safety on county roadways. Through collective action on the part of all roadway system stakeholders— from system operators and vehicle manufacturers to law enforcement and everyday users—a Safe System approach anticipates human mistakes with the goal of eliminating 1 Belin, M.-Å., Tillgren, P., & Vedung, E. (2012). Vision Zero- a road safety policy innovation. International Journal of Injury Control and Safety Promotion, 19, 171-179. 2 World Health Organization (2011). Decade of Action for Road Safety 2011-2020. Retrieved from https://www.who.int/roadsafety/ decade_of_action/plan/plan_en.pdf, pg. 9. traditional approach Prevent crashes Improve human behavior Control speeding Individuals are responsible React based on crash history safe system approach Prevent deaths and serious injuries Design for human mistakes/limitations Reduce system kinetic energy Share responsibility Proactively identify and address risks fatal and serious injuries for all road users.1 A Safe System acknowledges the vulnerability of the human body when designing and operating a transportation network, in terms of the amount of kinetic energy transfer a body can withstand. According to the World Health Organization, the goal of a Safe System is to ensure that if crashes occur, they “do not result in serious human injury.”2 A Safe System approach addresses the five elements of a safe transportation system— safe road users, safe vehicles, safe speeds, safe roads, and post-crash care—in an integrated manner and through a wide range of interventions (see Figure 1). 11Contra Costa County Vision Zero Action Plan The Safe System approach to road safety started internationally as part of the Vision Zero proclamation that no one should be killed or seriously injured on the road system.3 Countries adopting the Safe System approach have achieved significant success in reducing highway fatalities, with reductions in fatalities between 50 and 70%.4 The Institute of Transportation Engineers (ITE) and the Road to Zero Coalition’s Safe System Explanation and Framework articulate that to anticipate human mistakes, a Safe System seeks to accomplish the following: • Separate users in a physical space (e.g., sidewalks, dedicated bicycle facilities) Figure 1 The Safe System Approach Source: Fehr & Peers for FHWA 3 Johansson, R. (2009). Vision Zero - Implementing a policy for traffic safety. Safety Science, 47, 826- 831; and Tingvall, C., & Haworth, N. (1999). An Ethical Approach to Safety and Mobility. Paper presented at the 6th ITE International Conference Road Safety and Traffic Enforcement. 6-7 September 1999, Melbourne, Australia. 4 World Resources Institute (2018). Sustainable and Safe: A Vision and Guidance for Zero Road Deaths. Retrieved from https://www.wri.org/publication/ sustainable-and-safe-vision-and-guidance-zero- road-deaths. 12 Contra Costa County Vision Zero Action Plan •Separate users in time (e.g., pedestrian scramble, dedicated turn phases) •Alert users to potential hazards •Accommodate human injury tolerance through interventions that reduce speed or impact force The recommendations in this report have been organized to follow the Safe System approach elements and to reflect the shared responsibility of system planners, designers, and users in support of the County’s safety goals. Two people on horse- back using a crosswalk in Bay Point 13Contra Costa County Vision Zero Action Plan A pedestrian with a dog crossing Danville Boulevard in Alamo 14 Contra Costa County Vision Zero Action Plan About Contra Costa County Contra Costa County occupies the northern part of the East Bay region of the San Francisco Bay Area. The County is primarily suburban and is home to approximately 1,153,600 people.5 Contra Costa County is broadly divided into three sub- regions, and the unincorporated areas include the following communities • West County — Kensington, El Sobrante, North Richmond, Rodeo, Crockett, Port Costa, Bayview-Montalvin Manor, East Richmond Heights, Rollingwood, Tara Hills • Central County — Canyon, Pacheco, Vine Hill, Clyde, Contra Costa Centre (Pleasant Hill BART station), Saranap, Alamo, Blackhawk, Tassajara, Briones, Diablo, Mountain View • East County — Bay Point, Bethel Island, Knightsen, Discovery Bay, Byron The County’s most notable landmark is Mount Diablo, but the County is also well known for its many trails and recreational facilities, including Acalanes Ridge, the Bay Trail, Briones Regional Park, Las Trampas Regional Wilderness, and the Carquinez Strait Regional Shoreline. A majority of the existing roadway network was built with a focus on motor vehicles. Multimodal traffic safety is a growing concern because of the suburban land use patterns in the County, major freeways running through the unincorporated areas, nearby recreational uses, and development occurring throughout the County. 5 Census Bureau American Community Survey (ACS) 2019 1-year estimates. Pedestrian- and bicycle- involved collisions have seen an upward trend in recent years. Historic auto-oriented land use patterns and a focus on reducing vehicle delay/ congestion over multi-modal accessibility and comfort have led to environments throughout the County where walking and bicycling is uncomfortable and safety concerns have arisen. To that end, this plan focuses on holistic interventions to decrease KSI collisions on County-maintained roadways. For demographic context, the County’s total population is 42% White, 18% Asian, 9% Black or African American, 26% Hispanic or Latinx, 0.2% Native Hawaiian and Other Pacific Islander, 0.3% American Indian and Alaskan Native, and 5% of another race or of two or more races. 15Contra Costa County Vision Zero Action Plan CHAPTER 2 16 Contra Costa County Vision Zero Action Plan VISION AND GUIDING PRINCIPLES 17Contra Costa County Vision Zero Action Plan Vision Statement Contra Costa County will have an equitable, sustainable, multimodal transportation system where users of all ages and abilities can travel conveniently, reliably, and free from harm. Bike infrastructure along San Pablo Dam Road 18 Contra Costa County Vision Zero Action Plan Guiding Principles As an equity-focused and community data-driven initiative to proactively implement multimodal transportation safety improvements, this Vision Zero Plan aims to eliminate fatal and severe injuries throughout unincorporated Contra Costa County by 2035. Key elements of this approach include the following: Safety is the highest priority: Motor vehicle collisions should not result in a fatality or serious injury on County roadways. They are preventable and unacceptable incidents. People make mistakes: Errant driver behavior will be taken into consideration for design, construction, operation, and continuous evaluation of roads to determine the impact of such driver behavior on the most vulnerable road users. Safety is a shared responsibility: The goal is to create a roadway system where users, roadway designers, law enforcement, and post-crash care cohesively reinforce safety. A data-driven approach: Ongoing evaluation should continue to identify where and why traffic collisions are occurring and prioritize projects and programs that eliminate fatal and severe collisions. Proactive and reactive data- driven engineering decisions have been and will be made to design and manage roadways to reduce the severity of collisions. Transportation networks must be equitable: The transportation networks in unincorporated Contra Costa County must be equitable to all road users and serve all ages and abilities. Equity Priority Communities6 will be considered as projects are developed. New safety interventions will not worsen equity concerns, especially as it relates to enforcement. Vision Zero will be accountable and transparent: Evaluation through an equity lens will be ongoing. The County strives to be transparent in its communications on roadway designs, prioritizing competing improvements, and use of resources needed to reduce fatal and severe collisions on County roadways. 6 5 4 3 1 2 6 These are formerly called “Communities of Concern” and defined by MTC as census tracts with a significant concentration of underserved populations, such as households with low incomes, people of color, or a combination of additional factors. 19Contra Costa County Vision Zero Action Plan CHAPTER 3 20 Contra Costa County Vision Zero Action Plan COLLISION HISTORY, RISK FACTORS, AND TRENDS 21Contra Costa County Vision Zero Action Plan For the SSAR, five years of the most current crash data available at the time (2014- 2018) were extracted from the Statewide Integrated Traffic Records System (SWITRS) and Transportation Injury Mapping System (TIMS) databases. The datasets include extensive collision detail, such as collision location, type, severity, parties involved, contributing factors, and more. The SSAR provides an in-depth analysis of this crash history data, identifying collision trends, location types, and hot spots for crashes resulting in a death or serious injury. This Vision Zero Report includes key highlights from that effort. Collisions on freeways and other roadways not maintained by the County, within city limits, or on private property were not included in this study.7 7 The exception is the surface section of State Route 4 from the intersection of Marsh Creek Road and Vasco Road eastward to the county line, collisions on which were included for analysis in this study. 22 Contra Costa County Vision Zero Action Plan Pedestrians at the Pleasant Hill/Contra Costa Centre BART Station 23Contra Costa County Vision Zero Action Plan Annual Collision Trends Annual collision trends show a rise in collisions since 2014. The total number of collisions across all modes rose from 413 in 2014 to 486 in 2018. Fatal and severe injury (KSI) collisions dipped in 2016, but show an upward trajectory. Fatal collisions peaked in 2015 and 2018, with 17 and 19 fatalities, respectively. Motor vehicle KSI collisions experienced a dip in 2016 but have increased since then. Bicycle-involved KSI collisions decreased from 2015 to 2016, remained constant between 2016 and 2017, and peaked in 2018 with eight KSI collisions. Pedestrian-involved KSI collisions saw a spike between 2016 and 2017, with KSI collisions jumping from four in 2016 to ten in 2017. Pedestrian and bicycle- involved collisions account for 23% of all KSI collisions. 0 10 20 30 40 50 60 70 80 2014 2015 2016 2017 2018Collisions Year Motor Vehicle Bicycle Pedestrian Figure 2 KSI Collisions by Year and Mode Source: Contra Costa County Systemic Safety Analysis Report (February 2021) 24 Contra Costa County Vision Zero Action Plan Collision Severity Vulnerable road users, including bicyclists and pedestrians, are more susceptible to fatal or severe injury collisions. In terms of collision mode, pedestrian- involved collisions led to the highest percentage of KSI collisions at 30%, with 10% of those collisions being fatal. KSI collisions comprised 10% of motor vehicle collisions and 15% of bicycle-involved collisions. 88%90%85% 70% 9%8% 12% 20% 3%2%3% 10% 50% 55% 60% 65% 70% 75% 80% 85% 90% 95% 100% All Collisions Motor Vehicle Bicycle PedestrianPecent of CollisionsMode Involved Injury Severe Injury Fatal Figure 3 Collision Severity by Mode Source: Contra Costa County Systemic Safety Analysis Report (February 2021) 25Contra Costa County Vision Zero Action Plan Temporal Trends The highest share of motor vehicle and pedestrian- involved KSI collisions occurred overnight (7 PM to 6 AM). Bicycle-involved KSIs occurred most frequently during the morning peak hours, between 6 AM and 10 AM. Figure 4 Motor Vehicle Collisions by Time of Day Source: Contra Costa County Systemic Safety Analysis Report (February 2021) 0 10 20 30 40 50 60 70 80 90 100 0 100 200 300 400 500 600 Overnight (7PM-6AM) Morning Peak (6AM-10AM) Midday (10AM-3PM) Evening Peak (3PM-7PM)KSI CollisionsAll CollisionsTime of Day All Collisions KSI 26 Contra Costa County Vision Zero Action Plan 0 2 4 6 8 10 12 14 16 18 0 5 10 15 20 25 30 35 40 Overnight (7PM-6AM) Morning Peak (6AM-10AM) Midday (10AM-3PM) Evening Peak (3PM-7PM)KSI CollisionsAll CollisionsTime of Day All Collisions KSI 0 1 2 3 4 5 6 7 8 9 10 0 10 20 30 40 50 60 Overnight (7PM-6AM) Morning Peak (6AM-10AM) Midday (10AM-3PM) Evening Peak (3PM-7PM)KSI CollisionsAll CollisionsTime of Day All Collisions KSI Figure 5 Bicycle-Involved Collisions by Time of Day Source: Contra Costa County Systemic Safety Analysis Report (February 2021) Figure 6 Pedestrian-Involved Collisions by Time of Day Source: Contra Costa County Systemic Safety Analysis Report (February 2021) 27Contra Costa County Vision Zero Action Plan Contextual Trends The top violations for motor vehicle KSI collisions were improper turning (33%) and DUI (29%); for bicycle- involved KSI collisions the top violations were unsafe speeds on the part of motorists(28%) and improper turning (28%); and for pedestrian-involved KSI collisions the top violations were pedestrian violations (39%), pedestrian right-of- way violations (18%), and improper turning violations (15%).8 Figure 7 Share of Collisions by Violation Category Source: Contra Costa County Systemic Safety Analysis Report (February 2021) 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% All Collisions KSI All Collisions KSI All Collisions KSI Motor Vehicle Bicycle PedestrianPercent of CollisionsDUI Following Too Closely Improper Passing Improper Turning Other Pedestrian Right of Way Pedestrian Violation Tra c Signals and Signs Unsafe Lane Change Unsafe Speed Wrong Side of Road Vehicle Right of Way 8 A pedestrian violation indicates that a pedestrian is at fault in the collision (e.g. crossing outside of a marked crosswalk or crossing against a do not walk signal), while a pedestrian right-of-way violation indicates that the driver is at fault (e.g. driver enters the crosswalk while a pedestrian has a walk signal). 28 Contra Costa County Vision Zero Action Plan Schoolchildren walking near Walnut Heights Elementary School 29Contra Costa County Vision Zero Action Plan Men were a party to 56% of all collisions, as well as 82% of bicycle-involved collisions and 57% of pedestrian- involved collisions. Figure 8 Sex of Parties and Victims to All Collisions Source: Contra Costa County Systemic Safety Analysis Report (February 2021) 0% 10% 20% 30% 40% 50% 60% Female Male Parties %Victims %Census 30 Contra Costa County Vision Zero Action Plan Figure 9 Sex of Parties and Victims to Bicycle- Involved Collisions Source: Contra Costa County Systemic Safety Analysis Report (February 2021) Figure 10 Sex of Parties and Victims to Pedestrian- Involved Collisions Source: Contra Costa County Systemic Safety Analysis Report (February 2021) 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% Female Male Parties %Victims %Census 0% 10% 20% 30% 40% 50% 60% 70% Female Male Parties %Victims %Census 31Contra Costa County Vision Zero Action Plan For all collision types, Black individuals were disproportionately the victim relative to share of the population, based on census data. Hispanic individuals showed higher rates of pedestrian-involved collisions relative to their share of the population, also based on census data. Figure 11 Race/Ethnicity of Parties and Victims for All Collisions Source: Contra Costa County Systemic Safety Analysis Report (February 2021) ALL 0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50% Asian Black Hispanic White Other Parties %Victims %Census 32 Contra Costa County Vision Zero Action Plan Figure 12 Race/Ethnicity of Parties and Victims for Bicycle- Involved Collisions Source: Contra Costa County Systemic Safety Analysis Report (February 2021) Figure 13 Race/Ethnicity of Parties and Victims for Pedestrian- Involved Collisions Source: Contra Costa County Systemic Safety Analysis Report (February 2021) 0% 10% 20% 30% 40% 50% 60% 70% Asian Black Hispanic White Other Parties %Victims %CensusPED 0% 10% 20% 30% 40% 50% 60% Asian Black Hispanic White Other Parties %Victims %Census 33Contra Costa County Vision Zero Action Plan ! ! !! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! !!! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! !!! ! ! ! ! ! 3101 3101 ·123 ·160 ·242 ·24 ·4 !"80 %&580 %&680 C:\CCC_VZ\basemap\HIN.mxdCountywide High Injur y Network and KSI Collisions !1, 1 High-Injury Network Incorporated Areas • KSI COLLISIONS - HIGH-INJURY NETWORK Figure 14 High-Injury Network and KSI Collisions on County-Maintained Roads in Unincorporated Contra Costa County, 2014-2018 34 Contra Costa County Vision Zero Action Plan High-Injury Network The High-Injury Network (HIN) spotlights roadways with a high concentration of severe injuries and fatalities, providing a comprehensive set of focused locations for countywide consideration in future project or funding decisions. The HIN accounts for 143 miles of roadways, representing 22% of the 662 miles of roadways maintained by the County. A total of 2,174 non-freeway collisions occurred in the study area between 2014 and 2018; the HIN captures 70% (or 1,528) of these collisions. A total of 252 of the 2,174 non- freeway collisions were KSIs; the HIN captures 73% (or 184) of these collisions. Pedestrian using a push button 35Contra Costa County Vision Zero Action Plan Contextual Data and Systemic Analysis A systemic analysis looks at crash history on an aggregate basis to identify high-risk roadway characteristics in locations that have not necessarily seen a high number of collisions. This approach allows the County to proactively apply for grant funding at high-risk locations and carry out safety investments and widespread implementation of projects to reduce potential severe and fatal collisions at these locations. The systemic analysis in the SSAR combined crash history and contextual data on roadway characteristics, as well as input from County staff and Technical Advisory Committee (TAC) members, to produce a set of 11 collision profiles that highlight the most common and severe collisions patterns in the County.Signage at the entrance of Kennedy Grove Recreation Area along San Pablo Dam Road 36 Contra Costa County Vision Zero Action Plan Profile Mode Profile Number Profile Name # of KSIs Modal Share 1 Driving Under the Influence 56 29% 2 Vehicles Crossing into Opposing Lanes on Rural Roads 17 9% 3 Roadway Departure Collisions on Rural Roads 40 21% 4 Broadside Collisions at Urban Intersections with Side Street Stop Control 7 5% 5 Collisions at Signalized Intersections of Major (5+ Lanes) and Minor (3 Lanes or Less) Streets 19 10% 6 Bicycle-Involved Collisions Along Rural Roadways Where Bicycle Facilities Do Not Exist 10 40% 7 Bicycle-Involved Broadside Collisions at Urban Intersections 4 16% 8 Pedestrian-Involved Collisions on Rural Roads Where No Sidewalk or Marked Crosswalks are Present 4 12% 9 Pedestrians Crossing Urban Roadways Midblock Outside Marked Crosswalks 8 24% 10 Pedestrian-Involved Collisions at Signalized Urban Intersections 4 12% 11 Pedestrian-Involved Collisions at Unsignalized Urban Intersections 6 18% List of Collision Profiles 37Contra Costa County Vision Zero Action Plan CHAPTER 4 38 Contra Costa County Vision Zero Action Plan COUNTER- MEASURES 39Contra Costa County Vision Zero Action Plan Curb Extensions Edge Line/ Center Line Rumble Strips Extend Yellow and All-Red Time + Green Bike Lane Conflict Zone Marking Pedestrian Hybrid Beacon Pedestrian Signage Raised Crosswalk Rectangular Rapid Flashing Beacon Reduce Curb Radius Sightline Obstruction Removal Road Diet Roundabout Speed Feedback Signs YOURSPEED Pedestrian- Scale Lighting Widen or Pave Shoulder Raised Median Install High Visibility Crosswalk Pedestrian Path Protected Facility on Intersection Approach Reconfigure or Remove Slip Lane 40 Contra Costa County Vision Zero Action Plan Safe Road Users Safe Speeds Post-Crash Care EmergingTechnologies EquityConsiderations Engineering Countermeasures The County’s SSAR provides in- depth guidance on engineering countermeasures for each collision profile, including decision-making frameworks for safety improvements, detailed descriptions of countermeasures, and the feasibility and implementation considerations for each of the engineering countermeasures. The countermeasures recommended by the SSAR for the various profiles and locations around the County are presented on the facing page, and detailed information for each can be found in the Appendix of the SSAR. Some of the most frequently-used countermeasures are shown below. These countermeasures focus on separating users in space and time to reduce conflicting movements, improving visibility for all users, and reducing kinetic energy transfer in the event of collisions. Non-Engineering Countermeasures The following sections present additional safety countermeasures to include Road Users and Post-Crash Care, supplementing the SSAR’s engineering-focused countermeasures on roadway design and speed reductions. Vehicle design does not fall within the County’s current purview, though opportunities to consider autonomous vehicle planning and intelligent transportation system technologies with future safety efforts are acknowledged. These non-engineering countermeasures are organized into five categories, as shown on the right. 41Contra Costa County Vision Zero Action Plan Transportation safety education plays an important role in shaping and shifting behavior. Many cities such as Seattle, Oakland, and Los Angeles, are including community engagement and education to make streets safer for all. For example, the Los Angeles Vision Zero Dignity-Infused Community Engagement (DICE) approach includes partnerships with local nonprofits, paid outreach work for those experiencing barriers to employment, and both large- and small-scale community engagement events. Public Education Media Campaign A public education media campaign focused on discouraging drinking and driving and/or speeding would complement engineering interventions targeting these risk factors in the County. Campaigns should also include the encouragement of increased awareness of pedestrians and bicyclists at night and appropriate crosswalk behaviors. Targeted education, such as on buses and bus shelters, on billboards, at movie theaters, or on local radio stations, may be directed at vulnerable populations with the help of local partners, and at certain behaviors of drivers, pedestrians, and bicyclists to deter specific collision types. Specific locations on the high-injury network, as well as partnered campaigns with the County’s Public Health Services Safe Routes to School team, may also be appropriate for concentrated educational messages. The County will consider joint efforts with Contra Costa Transportation Authority (CCTA) to develop outreach education campaigns focusing on common violations leading to fatalities and severe injuries, based on the collision profiles identified in the SSAR. Education and outreach campaigns could target the following: •Reducing driving under the influence, as 29% of KSI collisions involved drugs or alcohol. •Providing education around driver behavior, as 33% of motor vehicle KSI collisions were caused by improper turning; the top violations for bicycle-involved KSI collisions were unsafe speeds and improper turning (both 28%). •Encouraging pedestrians to cross in crosswalks and drivers to yield to pedestrians, to complement engineering countermeasures addressing the need for safer crossings, as 39% of KSI collisions were pedestrian violations and 18% of KSI collisions were pedestrian right-of-way violations. Safe Road Users 42 Contra Costa County Vision Zero Action Plan Education Materials on New Roadway Design Changes Temporary demonstrations, like pop-up installations, can physically showcase proposed safety infrastructure and emergency response to the public in a tangible way. Using social media platforms such as NextDoor to prepare and promote materials and videos focused on new types of roadway designs and the County’s major violation issues could direct community conversations for meaningful outcomes. Partner with Local Experts Local partners should serve as community liaisons between the County and the public. Working with community partners and public institutions that have relationships with residents, such as local libraries and the Boys and Girls Clubs of Contra Costa, strengthens the engagement process by building trust and drawing on an established base of stakeholders. Local partners could help tailor the engagement process or incorporate engagement into existing programs and resources to educate people more effectively about roadway safety. Partner with Local Schools on Transportation Safety The County could partner with local schools to promote safe driver behavior. Education campaigns could involve students promoting safer driving to their parents by holding signs during pick- ups and drop-offs. Expanding existing youth programs led by the County’s Health Services presents an opportunity to provide ongoing Safe Routes to School education to all students each year. Office of Traffic Safety (OTS) grants also offer a variety of education programs intended to teach high school students about the dangers of alcohol and driving, including Every 15 Minutes, Sober Graduation, and DUI mock trials. 43Contra Costa County Vision Zero Action Plan The goal of high-visibility enforcement is to promote voluntary compliance with traffic laws and, according to National Highway Traffic Safety Administration (NHTSA) research, it is one of the most effective enforcement strategies for safety outcomes.9 Roadway networks within the County should address the safety of all road users, including those who walk, bike, roll, drive, and ride transit. Roadway design and management should encourage safe speeds, separate users in space and time, reduce kinetic energy transfer, and manipulate crash angles to ensure that collisions do not result in a fatality or serious injury. The SSAR provides engineering design recommendations for traffic calming such as lane narrowing, road diets, advanced yield and stop markings, and speed feedback signs, but these improvements should be complemented with enforcement tactics. Safe Speeds 9 Richard, C. M., Magee, K., Bacon- Abdelmoteleb, P., & Brown, J. L. (2018). Countermeasures That Work: A Highway Safety Countermeasure Guide For State Highway Safety Offices, 2017 (No. DOT HS 812 478). United States. Department of Transportation. National Highway Traffic Safety Administration. https:// www.nhtsa.gov/sites/nhtsa.gov/files/ documents/812478_countermeasures- that-work-a-highway-safety- countermeasures-guide-.pdf. Accessed May 3, 2021. High-Visibility Enforcement High-visibility enforcement is a multifaceted approach to enforcement. This approach involves garnering public attention to traffic safety laws through highly visible patrols, such as checkpoints, saturation patrols, or message boards. OTS provides three grant funding sources to supplement CHP in their high-visibility enforcement. The goal for Get Education and Ride Safe III (GEARS III) is to reduce the number of motorcycle-involved KSI collisions. The goal of the Safer Highways Statewide grant is to reduce the number of alcohol- involved KSI collisions. Lastly, the Regulate Aggressive Driving and Reduce Speed V (RADARS V) grant is aimed at reducing the number of victims killed or injured in speed, improper turning, driving on the wrong side of the road, or reckless driving-related collisions. 44 Contra Costa County Vision Zero Action Plan Automated Enforcement Automated enforcement methods, such as red-light cameras or speed safety cameras, equitably target the specific drivers who are behaving dangerously. A strictly data-driven approach to automated enforcement might place red-light or speed cameras in locations with the highest number of collisions; however, speed safety cameras are not currently allowed in California. The County should monitor potential changes to state legislation for future use of this critical tool, should it become available. Cross-Sector Partnerships Alternatives to law enforcement involve investing in cross-sector partnerships to promote transportation safety. The County could consider the following: • Hiring community partners as Street Safety Ambassadors to canvas corridors with severe traffic fatalities or where communities are experiencing the most traffic stops or tickets for traffic violations. Hiring community members as Street Safety Ambassadors would also serve as an opportunity to build trust between government agencies and the public, since community partners typically have pre- existing relationships in the community. • Hiring social workers, mental health counselors, addiction specialists, and other unarmed, specially trained professionals can supplement traffic enforcement. Partnering with local departments of mental health and public health may de-escalate traffic enforcement by treating traffic safety violations as a public safety issue. 45Contra Costa County Vision Zero Action Plan Post-Crash Care Post-crash care is more than just medical care. It also includes the training and design of emergency vehicles and roadway infrastructure. Post-crash care also includes providing additional resources to the victims and their families such as resources for physical and mental rehabilitation, including support from organizations such as Families for Safe Streets. Emergency Medical Services Response Victims involved in a collision have a higher chance of survival if they can quickly receive medical care. In many cases, law enforcement officers and fire department staff are the first responders to arrive at a collision location. In addition to equipping all first responders with the appropriate training, improving response times for EMS would help improve the chance of survival for collision victims. Collisions can also put the lives of first responders and other road users at risk due to increased congestion during the crash response, which may lead to secondary crashes. The County could work with EMS to improve response times and ensure safety in both arriving at and attending to patients at the scene. Strategies include designing emergency vehicles to be highly visible (e.g., retroreflective striping and chevrons, high-visibility paint, and built-in passive light) and implementing emergency vehicle signal preemption, which allows emergency vehicles to break a normal signal cycle and proceed through an intersection. 46 Contra Costa County Vision Zero Action Plan Bike infrastructure along San Pablo Dam Road 47Contra Costa County Vision Zero Action Plan Trauma Care Effective emergency trauma care can increase crash survival rates by as much as 25%, and an effective trauma care coordination system can reduce fatalities by 50%.10 Contra Costa County could work with EMS and identify funding sources to provide the highest care for victims. Recommended strategies to improve trauma care include providing funding for appropriate first responder equipment (e.g., hydraulic and pneumatic extrication tools), research for and adoption of technology aimed at reducing triage time (e.g., automatic vehicle reporting of severe crashes to EMS, EMS vehicle collision avoidance systems, and geolocation of nearest EMS vehicles), and promotion of federal- and state-certified training programs. Fatal Crash Response Team In the event of a traffic fatality, analysis and evaluation are crucial in addressing the burden of traffic mortality and tracking progress toward eliminating fatalities on County roadways. One strategy would be for a designated person at the County to notify a cross-agency group after each fatal crash, including police, transportation officials, public health officials, and the County Board of Supervisors. This would assist with accurate investigation and documentation of potentially relevant infrastructural and environmental crash factors, while identifying other additional factors that may have contributed to the fatal crash outcome. It can also expedite interventions to improve the crash location/circumstances and address similar risk factor locations and situations. Post-Crash Care 10 Office of Traffic Safety (OTS) (2020). California Highway Safety Plan 2020. Retrieved from https://www.ots.ca.gov/wp- content/uploads/sites/67/2020/02/HSP-Final-back-2-4.pdf. Pg. 106. 48 Contra Costa County Vision Zero Action Plan Policy, Practices and Additional Resources When individuals are injured in collisions, they rely on emergency first responders to quickly locate them, stabilize their injuries, and transport them to medical facilities. Post-crash care also includes forensic analysis at the crash site and traffic incident management, so that traffic flow may be restored as safely and quickly as possible. Policy action through the justice system and appropriate design of roadways to lessen the risk of future crashes can also help inform our safety programs. Crash reporting practices, such as complete data collection and documentation of road user behavior and infrastructure, and sharing data across agencies or organizations (e.g., among police departments, transportation officials, and hospitals) can help lead to a greater understanding of the holistic safety landscape, and thus lead to improved investments in safety. To ensure a crash survivor receives the care needed to recover and restore body and mind to an active life within society, medical rehabilitation with specialists can range from orthopedics, neurosurgery, physical and occupational therapy, and prosthetics to psychology and neuropsychology. Resources for crash survivors, their family, and friends, can be found on the County’s website. Severe and fatal collisions not only affect the victim involved, but their family and friends as well. Across the nation, in Canada, and locally in the San Francisco Bay Area, there are chapters of Families for Safe Streets. This group advocates at the state capitol in Sacramento and works with lawmakers and non-profits like Mothers Against Drunk Driving to share their stories and testify before legislative committees. Supporting victims’ families can come in many forms. World Day of Remembrance for Road Traffic Victims is an annual event held on the third Sunday in November in remembrance of those who have died or have been affected by motor vehicle collisions, and to draw attention to the goal of Vision Zero. 49Contra Costa County Vision Zero Action Plan Creating an equitable framework for all modes of transportation in the county and removing transportation barriers for historically marginalized communities, especially communities of color, should ensure safe and fair transportation options so that all road users have a safe route and access to basic community services. The County will proactively work to address the inequities built into the current transportation system to keep vulnerable members of the community safe.11 Funding and Project Prioritization Ten priority engineering projects were identified and prioritized based on their perceived competitiveness for grant funding and alignment with County priorities, and were ranked by priority by the community. The County can apply for grant funding opportunities, such as California’s Active Transportation Program, prioritize projects that increase safety and travel options for people walking and bicycling and ensure that disadvantaged communities fully benefit from the ATP. California Office of Environmental Health Hazard Assessment’s (OEHHA) CalEnviroScreen and the Metropolitan Transportation Commission’s (MTC) Equity Priority Communities scores show part of Contra Costa County within the 25% most disadvantaged areas, making these priority areas for state and local funding opportunities. EquityConsiderations Culturally- Relevant Engagement Community engagement is not a one-size-fits-all model, as different communities have different needs. By developing culturally relevant engagement strategies that would be available on the County’s website, participants would feel welcomed to participate in conversations about safety. Culturally relevant engagement strategies help education and programming around traffic safety reach a larger audience and be more impactful. For example, including cultural markers of a local community, such as contracting with popular local food vendors to cater engagement activities, may be a creative and welcoming way to engage residents. Meeting people “where they are” to gather input on safety issues at local parks can more effectively engage parents and children, rather than expecting families to attend a meeting at a government building. 11 FHWA (2018). Integrating the Safe System Approach with the Highway Safety Improvement Program. https://safety.fhwa.dot. gov/hsip/docs/fhwasa2018.pdf. Accessed May 3, 2021. 50 Contra Costa County Vision Zero Action Plan Traffic Enforcement Through statistical analysis (traffic volumes, collision data, speed surveys, etc.) and observations and concerns received from citizens and key stakeholders regarding safety, CHP is dedicated to reduce collisions through preventative enforcement based on data- driven concerns and locations. Some agencies are shifting enforcement efforts to equity-based strategies that target specific reckless behaviors posing the highest safety risk while working to mitigate potential inequities in enforcement. Other agencies are looking for opportunities for non-sworn officers to be engaged in transportation enforcement activities, as appropriate. Equity can also be considered in a range of enforcement strategies, including progressive fine structures, analysis of demographic data in traffic citations, community- based alternatives to police enforcement, and investment in social programs that alleviate enforcement burdens. Currently, fine structures, including any proposed changes and base fines for most offenses when a bill becomes law, is set by the Legislature and not CHP. Additional fines, fees, and penalties are assessed by local Counties and the State. CHP should update the County of any changes in implementing any of these suggested equitable enforcement strategies: •Progressive traffic fine structures, such as a sliding scale based on a driver’s income, development of payment plans, or the opportunity for first offenders to take a safety class focusing on driver behavior changes may be considered. •The analysis of available demographic data and the location of traffic citation would help the County understand if traffic enforcement is being implemented universally or if specific communities are experiencing disparities in enforcement. •Assessment of traffic citation demographics and geographic data would help uncover inequities in policing and the enforcement of traffic safety. 51Contra Costa County Vision Zero Action Plan EmergingTechnologies features and technologies (e.g., along key roadways and intersections) to better understand and monitor risk scenarios in partnership with CCTA. •Public crowdsourcing — Online web crowdsourcing platforms, such as UC Berkeley’s SafeTREC Street Story tool (available in English and Spanish), allow anyone to anecdotally report incidents of near misses: https://safetrec.berkeley.edu/ tools/street-story-platform- community-engagement These data points are publicly available for analysis and contain important contextual information based on geographic location (e.g., road conditions, street lighting, and travel mode). Using a platform like Street Story in future projects could also advance community education and engagement around road safety by providing an outlet and way for people to connect around each other’s stories. collection technologies are reducing that limitation. The County could consider using examples of surrogate safety measure technologies to help close the gap and provide key safety insights including the following: •Video data — Video machine learning is an effective means of classifying collisions and collecting near-miss and hard breaking data. Data vendors, such as StreetLight Data, have partnered with Ford Motors to combine multiple datasets, including connected vehicle data, to provide information such as hard braking data. This information can provide the County a deeper understanding of hotspots where motorists need to brake hard to avoid a collision between a pedestrian, bicyclist, or other vehicle. CCTA has purchased StreetLight Data, and the County could consider investing in additional Recent advancements in transportation technology have not only introduced new transportation modes and travel patterns but have also presented opportunities to better understand travel behavior and encourage safe behavior. Crash Risk Indicators Surrogate safety measures, such as “near-miss” collisions, hard braking data, community- reported hazards, and high stress facilities, can provide a fuller understanding of the safety landscape and enable proactive interventions. “Near misses” have historically been difficult to study in practical safety applications due to an overall lack of reported information; however, new data 52 Contra Costa County Vision Zero Action Plan Data Collection, Inventory, and Management Up-to-date data on transportation infrastructure, including roadway characteristics, intersection characteristics, and signs, are valuable for planning and implementing future improvements. With an updated inventory, the County could also allow for the identification of project synergies, such as including a safety countermeasure with a repaving project. Finally, enhanced contextual data supports systemic safety analysis for future safety plans and evaluations. Examples of service providers available to assist with this work include the following: •Mapillary uses crowdsourced or privately provided street-level imagery to extract and map signs, streetlamps, sidewalks, signals, and other objects: https://www. mapillary.com/ •Ecopia uses satellite imagery to extract features such as road centerlines, roadway cross-sections, sidewalks, and more: https://www.ecopiatech.com/ Emerging Vehicle Technologies Safe vehicles are another element of the Safe System approach, and will increasingly add more redundancy or avoidance features in the system. Leveraging connected and autonomous vehicle (CAV) technology and identifying crash-avoidance systems with vehicle manufacturers is key in ensuring vehicles are safe for all road users in the future. The County currently does not have purview to design vehicles, but could take policy and design of County roadways into consideration as vehicle technology advances. Connected Systems and Vehicles Smart signal technology enables agencies to collect data at multiple intersections, providing a high- resolution understanding of how people are using the roadway in real time. Connected vehicles are another part of this system. They wirelessly communicate with other vehicles and infrastructure (like signals) to provide data for instantaneous decision-making (e.g., reporting driver speed or collisions). Data from signals in combination with data from vehicles could allow the County to deploy real time speed-related signal operations, allowing for enhanced safety through adaptable systems. The County should consider upgrades to infrastructure as connected systems and vehicle technology advance. 53Contra Costa County Vision Zero Action Plan DUI Strategies and Considerations The “Collision History, Risk Factors, and Trends” chapter of this report includes the 11 collision profiles from the SSAR that highlight the most common and severe collision patterns on unincorporated County roadways. Safe road users, safe speeds, and safe roads elements can complement the engineering countermeasures listed in the SSAR for all 11 emphasis areas. One profile, driving under the influence (DUI), is a major factor in fatal and severe collisions in the County that will require a full Safe System approach to address. In addition to engineering-focused countermeasures, DUI collisions also require non-infrastructure prevention programs. The County is committed to implementing policy to reduce the rates of driving under the influence. These policies generally fall under three categories: 1.Deterrence policies focus on raising the actual and perceived risk of detection of driving under the influence. These policies should be highly visible to increase awareness of the risks of driving under the influence. Publicized sobriety checkpoints, saturation patrol, and other forms of high-visibility enforcement are effective for safety outcomes. 2.Prevention and education policies focus on mobilizing and educating the community and intervening before driving under the influence takes place. According to NHTSA research, alcohol problem assessment and treatment programs, as well as alcohol intervention in settings such as a doctor’s office, are highly effective strategies for improving safety outcomes.12 3.Limited access policies focus on making underage access to alcohol and drugs more difficult, and seek to limit excessive alcohol consumption. Increasing funding for efforts that focus on prevention and education, such as alcohol problem assessment and treatment programs, would support less-punitive measures to reduce DUI collisions. 12 National Academies of Sciences, Engineering and Medicine (2005). A Guide for Reducing Alcohol-Related Collisions. Retrieved from https://doi. org/10.17226/23419. pg. 106. 54 Contra Costa County Vision Zero Action Plan Danville Boulevard through downtown Alamo 55Contra Costa County Vision Zero Action Plan CHAPTER 5 56 Contra Costa County Vision Zero Action Plan PROJECT DEVELOPMENT 57Contra Costa County Vision Zero Action Plan Project Development The 11 collision profiles provided a blueprint for Contra Costa County to prioritize countermeasures to reduce KSI collisions. Chapter 3 of the SSAR provides an overview of each collision profile, including a description of the profile, a map of the collisions, key statistics, and applicable countermeasures for feasibility and implementation considerations. Potential priority projects are identified in consideration of the 11 collision profiles, along with input from the County team and TAC members. MTC’s Equity Priority Communities are reviewed when prioritizing projects. This is taken into consideration when improvements can be made in underserved communities. Thirty-five priority projects were identified and categorized as Tier Zero, Tier One, and Tier Two as follows: •Tier Zero corresponds to a location the County has recently enhanced or has secured funding to improve, prior to the development of this plan; the County will monitor these locations to identify if the improvements were successful in meeting the County’s safety goals for the projects. •Tier One corresponds to the top ten projects recommended by the SSAR. •Tier Two corresponds to the project locations not identified as Tier Zero or Tier One, but are identified as important locations for future prioritization efforts or those with opportunistic funding measures. The ten Tier One projects are highlighted in the following cutsheets with further detail on project descriptions, related profiles (refer to pg. 37), collision history at the project site, and modal information. Also included are benefit-cost information for each project, which are used to summarize a project’s overall relationship between the relative costs and benefits associated with implementing the projects (e.g. crash reduction). This analysis provides a quantitative measure to help decision makers prioritize projects and apply for grant funding. 58 Contra Costa County Vision Zero Action Plan 3101 3101 ·123 ·160·242 ·24 ·4!"80 %&580 %&680 C:\CCC_VZ\basemap\Project_Locations.mxdCountywide High Injur y Network and KSI Collisions 28 29 27 19 17 3224 31 35 30 21 18 16 22 26 34 33 25 14 13 10 15 9 12 11 8 7 6 5 3 2 1 4 23 20 TIER ZERO PROJECTS5 TIER ONE PROJECTS10 TIER TWO PROJECTS20 Figure 15 Map of Project Locations 59Contra Costa County Vision Zero Action Plan 6 $811,500 $21,277,289 26.22 B/C RATIO TOTAL BENEFITS TOTAL COST NUMBER OF KSI COLLISIONS ADDRESSED TARGET MODES Appian Way / Valley View Road / Sobrante Avenue intersections PROJECT 6 Profiles Addressed 10 114578 Project Statistics This project targets all modes of travel: vehicles, bicyclists, and pedestrians. Flashing beacons, sidewalks extended at corners, and median islands enhance the visibility of pedestrians to drivers, limit pedestrian exposure in an intersection, and provide a space for pedestrians to wait in the median before entering the remaining part of the crossing. A transportation analysis study is also recommended to determine the feasibility of converting to a roundabout or traffic signal. 60 Contra Costa County Vision Zero Action Plan 7 $575,600 TOTAL COST 59.44 B/C RATIO NUMBER OF KSI COLLISIONS ADDRESSED TARGET MODES Byron Highway from Clifton Court Road to the California Aqueduct crossing PROJECT 7 Profiles Addressed 2 3 $32,225,550 TOTAL BENEFITS Project Statistics Widening of the shoulder, as well as installation of vertical motor vehicle barriers, rumble strips (roadways features that cause a vibration and an audible rumbling noise when driven over), and “Do Not Pass” signs are ways to reduce passing conflicts between motor vehicles and bicyclists. The County should coordinate discussions with Caltrans on the SR 239 project. 61Contra Costa County Vision Zero Action Plan 4 $176,400 $12,031,755 68.21 B/C RATIO TOTAL BENEFITS TOTAL COST NUMBER OF KSI COLLISIONS ADDRESSED TARGET MODES Camino Diablo/ Vasco Road Intersection PROJECT 8 Profiles Addressed 5 Project Statistics Updating traffic signal timing and using technology to help drivers navigate busy intersections are improvements to consider in addressing the top collision trends. Installing additional signage to alert drivers to not make a right turn on to Vasco Road from westbound Camino Diablo when their light is red is also recommended. The County should coordinate discussions with Caltrans on the SR 239 project. 62 Contra Costa County Vision Zero Action Plan Canal Road/Bailey Road Intersection and the De Anza Trail crossing at Bailey Road PROJECT 9 Profiles Addressed 10579 4 NUMBER OF KSI COLLISIONS ADDRESSED $301,400 TOTAL COST $13,342,109 TOTAL BENEFITS 44.25 B/C RATIO Project Statistics TARGET MODESThis project targets improvements for vehicles, bicyclists, and pedestrians. A two-way cycle track along Bailey Road from Willow Pass Road to Pittsburg-Bay Point BART Station Access that includes ADA-compliant sidewalks with a buffer zone to the De Anza Trail should be considered. At Canal Road, recommended improvements include installing a northern crosswalk and updating signal timings to ensure enough time is given to vehicles moving through the intersection when the light is red before giving vehicles traveling on the intersecting street a green light. 63Contra Costa County Vision Zero Action Plan 3 $559,300 $14,049,051 25.11 B/C RATIO TOTAL BENEFITS TOTAL COST NUMBER OF KSI COLLISIONS ADDRESSED TARGET MODES Profiles Addressed 1079 Concord Avenue from Walnut Creek Channel to I-680 PROJECT 10 Project Statistics Installing speed feedback signs and extending the left turn lane to hold more vehicles on the westbound approach at Diamond Boulevard are near term improvements. Looking ahead, a partnership with the City of Concord to reduce the number of vehicle lanes to install a protected bike lane and provide additional bicycle and pedestrian improvements is recommended. 64 Contra Costa County Vision Zero Action Plan 2 $904,200 $19,983,535 22.10 B/C RATIO TOTAL BENEFITS TOTAL COST NUMBER OF KSI COLLISIONS ADDRESSED TARGET MODES Profiles Addressed 11479 Danville Boulevard from Jackson Way to La Serena Avenue PROJECT 11 Project Statistics From Jackson Way to Stone Valley Road, the planned single lane roundabout at Orchard Court should be accommodated along with a reduction in vehicle travel lanes through the corridor to Alamo Square Drive. This would also include pedestrian and bicycle improvements at the Stone Valley Road intersection and relocation of bus stops. From Las Trampas to La Serena Avenue, sidewalks should be installed on both sides of the street along with pedestrian enhancements that include flashing beacons, sidewalks extended at corners, median islands, ADA compliant curb ramps, and high-visibility crosswalks. Buffered bike lanes should be installed where missing throughout this corridor. 65Contra Costa County Vision Zero Action Plan Marsh Creek Road from Deer Valley Road to Clayton city limits PROJECT 12 8 NUMBER OF KSI COLLISIONS ADDRESSED $919,300 TOTAL COST $59,847,337 TOTAL BENEFITS 65.10 B/C RATIO Project Statistics TARGET MODES Profiles Addressed 2 3 6 Curve-warning signs, rumble strips, speed feedbacks signs, and other roadway improvements would benefit both motorists and bicyclists. Additional improvements include trimming vegetation and installing lighting to provide more visibility. The project also includes installation of paved pull- out areas for traffic enforcement. 66 Contra Costa County Vision Zero Action Plan San Pablo Avenue from California Street to Merchant Street PROJECT 13 8 NUMBER OF KSI COLLISIONS ADDRESSED $9,777,800 TOTAL COST $36,502,091 TOTAL BENEFITS 3.73 B/C RATIO Project Statistics TARGET MODES Profiles Addressed 2 3 6 8 Along San Pablo Avenue, improvements to consider include a reduction in the number of vehicle travel lanes to provide space for a two-way bicycle and pedestrian path on the north side of the roadway, as well as installing curve-warning signs, speed feedback signs, and additional lighting. 67Contra Costa County Vision Zero Action Plan San Pablo Dam Road from May Road to the Kennedy Grove Entrance PROJECT 14 1 NUMBER OF KSI COLLISIONS ADDRESSED $72,900 TOTAL COST $882,151 TOTAL BENEFITS 12.05 B/C RATIO Project Statistics TARGET MODES Profiles Addressed 2 3 4 5 6 7 9 This project includes multiple improvements along this stretch of San Pablo Dam Road. The intersection with Valley View Road is noted as a hot spot location from residents. Reconfiguring the intersection to have one eastbound receiving lane that would open up to two lanes after Olinda Road, along with roadway and sidewalk improvements, would benefit all road users. Other improvements to consider include installing a roundabout at Tri Lane, installing additional signs to notify drivers when they must share the road with bicyclists, installing enhanced pedestrian crossing near bus stops, and completing a speed study. 68 Contra Costa County Vision Zero Action Plan Willow Pass Road from Port Chicago Highway to Crivello Avenue PROJECT 15 7 NUMBER OF KSI COLLISIONS ADDRESSED $2,437,500 TOTAL COST $40,300,975 TOTAL BENEFITS 16.53 B/C RATIO Project Statistics TARGET MODES Profiles Addressed 4 5 7 9 Reducing the number of vehicle travel lanes along Willow Pass Road between Port Chicago Highway and North Broadway Avenue would allow for protected bike lanes to be installed. Crosswalks that are uncontrolled, meaning a crosswalk where drivers do not have to stop for a stop sign or traffic signal, should be analyzed to ensure they are consistent with the latest best practice guidance for uncontrolled crossings. Lastly, traffic signal timing should be updated to smooth traffic flow and provide pedestrians with a head start when crossing. The head start provides additional times for pedestrians to cross and enhances the visibility of pedestrians to drivers. 69Contra Costa County Vision Zero Action Plan CHAPTER 6 70 Contra Costa County Vision Zero Action Plan SAFETY EFFORTS AND PROGRAMS 71Contra Costa County Vision Zero Action Plan In recent years, efforts to improve transportation safety in the County have included a thorough analysis of collisions and applicable engineering countermeasures through the Systemic Safety Analysis Report (SSAR), as well as grants from the Office of Traffic Safety for enforcement, education, and outreach programs. Contra Costa County Systemic Safety Analysis Report Completed in early 2021, Contra Costa County’s Systemic Safety Analysis Report (SSAR) lays the groundwork and provides the resources necessary for the preparation of successful Highway Safety Improvement Program (HSIP) and other local and federally funded grant applications sought by the County. The study was funded through the SSAR program grant provided by the California Department of Transportation (Caltrans). The SSAR program, initiated by Caltrans, helps local agencies take a strategic approach to identify systemic and hot spot safety improvement projects by completing a system-wide, multi-year, data- driven analysis of collisions. With a focus on engineering interventions, the SSAR includes collision and roadway database development, a review of local collision data, a safety data analysis, collision profile development, safety countermeasure selection, and project development. Programs Under Way The County has several existing programs and grants focused on educating the community on multimodal safety. Chapter 6 includes additional funding sources to consider as the County expands its outreach and educational campaigns. Safe Routes to School The National Center for Safe Routes to School delivers a way for communities to provide education and programs to promote and educate students on walking and biking to school without safety as a barrier. Contra Costa Health Services works with schools and Community Based Organizations (CBO) throughout the County to promote in-class presentations, leadership development, Walk/ Bike to School Days, assemblies, and bicycle rodeos. They also encourage on-campus kiosks promoting safe walking and bicycling. Street Smarts Diablo Region Streets Smarts Diablo is funded through 511 Contra Costa, with funding from the Contra Costa Transportation Authority and the Bay Area Air Quality Management District’s Transportation Fund for Clean Air. This program provides safe walking and bicycling assemblies for students in elementary, middle, and high school. This program currently serves the southwest part of the County. 72 Contra Costa County Vision Zero Action Plan Summer Bike Challenge 511 Contra Costa hosts the annual Summer Bike Challenge, free for people of all ages and abilities. Between June and August, participants bike to as many locations identified in their community as possible, and prizes are awarded at the end of the summer. California Highway Patrol (CHP) Programs California Highway Patrol has various DUI checkpoints set up throughout the County, although they have been less frequent recently due to the COVID 19 pandemic. CHP also uses social media and hosts presentations at schools and at the district attorney’s office warning students of the dangers of driving under the influence. CHP hosts a Start Smart program to inform newly licensed or soon-to- be licensed teenagers and their parents/guardians of the dangers of excessive speed, driving under the influence, and distracted driving. Mothers Against Drunk Driving (MADD) MADD is a non-profit organization seeking to stop drunk driving, support those affected by drunk driving, prevent underage drinking, and strive for stricter impaired- driving policies. In the county, MADD hosts in-person Victim Impact Panels where participants share their stories of how drunk and drugged driving has affected their lives and the lives of their families and friends. The panel is aimed at helping offenders recognize and internalize the lasting and long-term effects of substance- impaired driving. Caltrans Grant Funding The Fixing America’s Surface Transportation (FAST) Act was signed into law on December 4, 2015. Under the FAST Act, the Highway Safety Improvement Program (HSIP) is a federal- aid program focusing on infrastructure projects to achieve significant reductions in fatalities and serious injuries on public roadways. The County applies for HSIP funding annually to improve county-maintained roadways and facilities. Complete Streets Corridor Studies The County’s Transportation Analysis Guidelines outlines Complete Streets implementation measures for existing and future roadways. The County strives to create a connected network of facilities accommodating all modes of travel, increasing connectivity across jurisdictional boundaries, and anticipating existing and future areas of origin and destination. A few recent Complete Streets projects the County has been working on are the Appian Way Complete Streets Project, the Danville Boulevard/Orchard Complete Streets Improvement Project, and the San Pablo Avenue Complete Streets Project. 73Contra Costa County Vision Zero Action Plan CHAPTER 7 74 Contra Costa County Vision Zero Action Plan FUNDING 75Contra Costa County Vision Zero Action Plan Although many candidate projects in the SSAR are well suited for HSIP funding, there are many other potential funding sources that may be available for additional efforts. The following summarizes potential local, state, and federal funding sources related to transportation safety. The County will also continue to look for opportunities to layer safety-related projects onto other capital improvement projects, as well as maintenance projects and through review and approval of private development. Developer Fees California law allows local governments to establish and charge a fee on residential and non-residential development to fund public facilities and to service population growth. Local agencies should update their transportation analysis guidelines to reflect safety improvements for all modes of travel. Public facility fees can be charged to new development based on density and traffic impacts, and can go to a variety of public facilities, including local roadways. Affordable Housing and Sustainable Communities Program (AHSC) The AHSC Program, administered by the Strategic Growth Council and implemented by the Department of Housing and Community Development (HCD), funds land use, housing, transportation, and land preservation projects to support infill and compact development that reduces GHG emissions. This program will assist project areas by providing grants and/ or loans, or any combination thereof, that will achieve GHG emission reductions and benefit Disadvantaged Communities and Low-Income Households though increased accessibility of affordable housing, employment centers, and key destinations via low-carbon transportation. This results in fewer vehicle miles traveled through shortened or reduced trip lengths or mode shifts from Single Occupancy Vehicles to use of transit, bicycling, or walking. The project areas this funding is geared toward are transit oriented development (TOD) Project Areas, Integrated Connectivity Project (ICP) Project Areas, or Rural Innovation Project Areas (RIPA). RAISE Grant The U.S. Department of Transportation is committed to create high-quality jobs, improve safety, protect our environment, and generate equitable economic opportunity for all American’s with their Rebuilding American Infrastructure with Sustainability and Equity (RAISE) grant. Projects will be evaluated based on merit criteria that includes safety, environmental 76 Contra Costa County Vision Zero Action Plan sustainability, quality of life, economic competitiveness, state of good repair, innovation, and partnership. It is one of the few DOT discretionary programs for which regional and local governments can directly compete for multimodal transportation funding. Lifeline Transportation Program The Metropolitan Transportation Commission (MTC) has created the Lifeline Transportation Program to evaluate state and federal funds to provide grants for mobility and accessibility needs in low- income communities across the Bay Area. New guidelines are established for each cycle and the projects must address transportation gaps or barriers identified in community-based transportation plans or other local planning efforts in low- income neighborhoods. Franklin Canyon Road 77Contra Costa County Vision Zero Action Plan SB 1 Funding The U.S. Department of Transportation’s Senate Bill 1 (SB 1), also known as the Road Repair and Accountability Act of 2017, is a landmark transportation investment to rebuild California by fixing neighborhood streets, freeways, and bridges in communities across California and targeting funding toward transit and congested trade and commute corridor improvements. The largest portion of SB 1 funding goes to California’s state-maintained transportation infrastructure. With this funding, Caltrans has a goal of repairing or replacing 17,000 miles of pavement in 10 years, spending $250 million annually for congestion solutions, over $700 million for better transit commutes, and supporting freight improvements. The other portion of SB 1 funding will go to local roads, transit agencies, and expanding the state’s pedestrian and cycle routes. SB 1 funds various grant programs. Local Partnership Program (LPP) The Local Partnership Program’s purpose is to provide local and regional transportation agencies that have passed sales tax measures, developer fees, or other imposed transportation fees, with a funding of $200 million annually from the Road Maintenance and Rehabilitation Account to fund aging infrastructure, road conditions, active transportation, and health and safety benefits projects. LPP funds are distributed through a 50% statewide competitive component and a 50% formulaic component. Both programs are eligible to jurisdictions with voter approved taxes, tolls, and fees dedicated solely to transportation and the competitive program. Local Streets and Roads Program (LSRP) California SB 1 has dedicated approximately $1.5 billion per year appointed by the State Controller (Controller) to cities and counties for basic road maintenance, rehabilitation, and critical safety projects on the local streets and roads system. Cities and counties must submit a proposed projects list adopted at a regular meeting by their board or council that is then submitted to the California Transportation Commission (Commission). Once reviewed and adopted by the Commission, eligible cities and counties receive funding from the Controller and an Annual Project Expenditure Report is sent to the Commission to be transparent with program funding received and expended. 78 Contra Costa County Vision Zero Action Plan Active Transportation Program (ATP) Funding The Active Transportation Program (ATP) was created by Senate Bill 99 to encourage increased use of active modes of transportation such as walking and biking. The goals of the ATP include, but are not limited to, increasing the proportion of trips accomplished by walking and biking, increasing the safety and mobility of non- motorized users, advancing efforts of regional agencies to achieve greenhouse gas reduction goals, enhancing public health, and providing a broad spectrum of projects to benefit many types of users, including disadvantaged communities. SB 1  directs $100 million annually to the ATP, with more than 400 of the funded projects being Safe Routes to School projects and programs that encourage a healthy and active lifestyle throughout students’ lives. Caltrans Sustainable Transportation Planning Grants The Sustainable Transportation Planning Grants include two parts: Sustainable Communities Grants and Strategic Partnerships Grants. The Sustainable Communities Grants have $29.5 million set aside to encourage local and regional planning goals and best practices cited in the Regional Transportation Plan Guidelines. The Strategic Partnerships Grants set aside $4.5 million to identify and address statewide, interregional, or regional transportation deficiencies on the state highway system in partnership with Caltrans. These grants were released for Fiscal Year 2020-21 and applications were due October 17, 2019. Grant announcements were made in June 2020. There is the possibility of another grant on the horizon, but Caltrans has not released any new information yet. Safe Routes to School (SRTS) Funding Safe Routes to School (SRTS) is a program promoting walking and bicycling to school through infrastructure improvements, tools, safety education, and incentives to encourage these modes of travel. Nationally, 10% to 14% of car trips during the morning rush hour are for school travel. SRTS can be implemented at the state, community, or local school district level. Competitive federal funding is available through the Fixing America’s Surface Transportation Act (FAST Act). Depending on the existing infrastructure, SRTS may require that education, transportation, public safety, and city planning agencies coordinate their effort. 79Contra Costa County Vision Zero Action Plan Transformative Climate Communities (TCC) Program The TCC Program funds community-led development and infrastructure projects that strive to make major advances in environmental, health, and economic benefits in California’s most disadvantages communities. Eligible improvements for this funding source include active transportation and public transit projects, transit ridership programs and passes for low-income riders, and encouraging education and planning activities to promote increased use of active modes of transportation. California Office of Traffic Safety (OTS) Grant Programs OTS administers traffic safety grants in the following areas: alcohol impaired driving, distracted driving, drug- impaired driving, emergency medical services, motorcycle safety, occupant protection, pedestrian and bicycle safety, police traffic services, public relations, advertising, and roadway safety and traffic records. 80 Contra Costa County Vision Zero Action Plan A cyclist on the Iron Horse Regional Trail 81Contra Costa County Vision Zero Action Plan CHAPTER 8 82 Contra Costa County Vision Zero Action Plan VISION ZERO CORE ELEMENTS AND THE ACTION PLAN 83Contra Costa County Vision Zero Action Plan The Contra Costa County Vision Zero Plan requires partnerships and collaboration across various jurisdictions, with local organizations, and with the community to be successful. Several strategies have been identified, along with the party/parties responsible for leading the action and supporting agencies. A timeline for implementation is provided, as well as performance metrics. These actions should be periodically revisited, and actions that are successful may be expanded; actions that are not successful will be eliminated and replaced with other strategies. As conditions and strategies evolve, the strategies and supporting elements will evolve as well. The Vision Zero strategies are categorized into three Core Elements: Leadership and Commitment Safe Roadways and Safe Speeds Data-Driven Approach, Transparency, and Accountability 84 Contra Costa County Vision Zero Action Plan A pedestrian crossing the street in Contra Costa Centre 85Contra Costa County Vision Zero Action Plan 1 The TAC will share updates on crash data, resources, current projects, policy evolution, funding opportunities, equity data, emerging issues, and other information. The County’s Public Works Department and Health Services Department will coordinate invites to stakeholders to participate in the TAC, which includes, but is not limited to, Social Services, Economic Development, Contra Costa County Transit Authority (CCCTA, also known as County Connection), Board of Supervisors (BOS), California Highway Patrol (CHP), and other non-profits and community based organizations (CBOs). Routine collaboration between stakeholders and partners will ensure that county-led engineering countermeasures are supported by coordinated efforts led by local and regional partners. Strategies for mutual accountability include conducting briefings and presentations at board and agency meetings, collecting and sharing information on a regular basis, and updating a public-facing database (or scorecard) on the progress toward Vision Zero. Partners • Contra Costa County Staff • CCCTA • BOS • CHP • Non-profit organizations and CBOs Timeline Ongoing Performance Measures Biannual or quarterly meetings, numerical (#) progress on priority projects and safety goals Leadership and Commitment Technical Advisory Committee (TAC) Legislation Education Funding 86 Contra Costa County Vision Zero Action Plan 2 Create a Contra Costa County Vision Zero Plan media kit. The media kit should provide information and resources, and offer educational opportunities to media outlets and member governments about Vision Zero to promote consistent messaging and crash reporting language. As collision updates are developed, promote achievements as well as ongoing efforts. Partners • Contra Costa County Public Works Department • Contra Costa County Health Services Department • CCTA • CHP • Member agencies Timeline Ongoing Performance Measures Number of safety-focused news articles, a reduction in use of the word “accident” in the reporting of collisions, number of transportation safety-related social media posts 3 Use County accounts linked to Facebook, Twitter, NextDoor or other various media outlets to share key elements of the plan, promote achievements, and keep the community updated on policies and project completion. Some examples include the following: • Radio — Radio ads are an effective way of advertising plans and updating the community. Vision Zero San Francisco used radio ad space to share information on the Vision Zero Plan and target speeding in the city. • Bus Banners and Bus Shelter Ads — Various transit agencies have bus stops throughout the County. Banners promoting safety messages and Vision Zero related messages can spread the word to community members far and wide. Bus stops throughout the County have ad space available for use by County staff and approved community service organizations. Public service messages are allowed up to 30 displays for a minimum of 30 days to advertise various efforts. • Movies — Movie-watching is enjoyed by all ages and serves as a great space for advertisements that can reach substantial sections of the community. Partners • Radio stations • Transit agencies • Advertisement agencies Timeline Ongoing Performance Measures Number of ads related to Vision Zero messages 87Contra Costa County Vision Zero Action Plan 4 Collaborate with public school districts and interested charter and private schools to provide additional transportation-related education. Tailor engagement toward middle and high school students, with a focus on empowering youth leaders to promote safe transportation in their own school communities, prioritizing Equity Priority Communities. Partners • County School Districts • Contra Costa County Public Works Department • Contra Costa County Health Services Department • CHP • 511 Contra Costa • Non-profit organizations and CBOs Timeline Ongoing — coordinate with TAC Performance Measures Number of Safe Routes to School projects implemented around the High-Injury Network (HIN) 5 Modify the County’s funding criteria to prioritize safety projects on the HIN and in Equity Priority Communities that address key crash profiles or otherwise reduce KSI crashes; Modify funding to ensure both proactive and reactive safety projects are deployed. Seek opportunities to institutionalize safety projects with other County efforts such as repaving programs and development impact review. Partners • Contra Costa County Public Works Department Timeline Annual (review progress) Performance Measures Percent of available funding awarded to projects on HIN; number of safety projects funded Leadership and Commitment Technical Advisory Committee (TAC) Legislation Education Funding 88 Contra Costa County Vision Zero Action Plan 6 Support legislation to allow use of speed safety cameras and changes to the 85th percentile speed limit setting process for more equitable enforcement and local speed limit setting capacities. Partners • Contra Costa County Public Works Department • Contra Costa County Health Services Department • Member agencies Timeline Within one year of plan adoption Performance Measures Number of additional funding streams identified for safety projects in the County; participation in lobbying efforts in support of these measures The intersection of San Pablo Dam Road and El Portal Drive in El Sobrante 89Contra Costa County Vision Zero Action Plan 7 Contra Costa County Public Works Department, local agencies, and TAC Members should develop guidelines, policies, and resolutions for the County, addressing safety-related aspects of street design, and incorporating Vision Zero and Safe System design principles. They should develop and implement Vision Zero and Safe System training aimed at County staff and elected officials to help encourage adoption and incorporation of these core elements within County programs, policies, and processes. Partners • Contra Costa County Public Works Department • Partnering local agencies and jurisdictions • Caltrans Timeline Start guideline development within one year of plan adoption Performance Measures Implementation of new design standards and monitoring of use; design standards updated to separate users in space and time and reduce kinetic energy transfer Safe Roadways and Safe Speeds 8 Conduct safety demonstrations/ pilot projects to test innovative safety interventions and implement quick-build projects. The 10 priority projects could be considered to implement as pilot projects as part of this action item. Partners • Contra Costa County Public Works Department • Partnering local agencies and jurisdictions • Caltrans Timeline At least one demonstration project per year Performance Measures Number of demonstration projects implemented, including the share of demonstration projects in Disadvantaged Communities and Equity Priority Communities Street and Roadway Design 90 Contra Costa County Vision Zero Action Plan The Bethel Island Bridge under construction 91Contra Costa County Vision Zero Action Plan 9 Conduct and prepare an annual crash analysis, including preparation of crash profiles and comparison of various time periods to better identify trends and progress toward Vision Zero. Analysis should layer available demographic and environmental justice data. Periodically update the HIN and Action Plan to reflect progress being made or develop new strategies if current actions are not achieving the desired results. Partners • Contra Costa County Public Works Department • Contra Costa County Health Services Timeline Annual (review progress); every five years (major plan update) Performance Measures Report safety improvements constructed to the Board of Supervisors on an annual basis, and progress toward Vision Zero; demonstrable and significant KSI reduction 10 Partner with local law enforcement agencies and healthcare providers to provide collision reporting and crash- related injury coding best practices to improve the value of data analysis, emphasizing data collection on speed, impairment, distractions and use of emerging mobility options like e-scooters and ride sharing at KSI collision locations. Partners • Contra Costa County Public Works Department • Contra Costa County Health Services Department • Caltrans • CHP • Healthcare providers Timeline Within two years of plan adoption Performance Measures Number of training sessions held with Law Enforcement and Public Health, incorporation of additional data into the collision dataset Data-Driven Approach, Transparency, and Accountability Data Collection, Monitoring, and Analysis 92 Contra Costa County Vision Zero Action Plan 11 The Public Works Department should work with the Public Health Department to determine how hospital data could be obtained to develop more comprehensive collision records. As hospital data becomes available, incorporate it into the data dashboard to develop performance measures tied to health equity outcomes, and address underreporting. Partners • Contra Costa County Public Works Department • Contra Costa County Health Services Department • Healthcare providers Timeline Within two years of plan adoption Performance Measures Incorporation of Public Health data in collision analytics 12 Leverage technology to better understand core collision factors and surrogate safety measures including collecting automated speed data and conducting near-miss analysis, hard braking hot spots, and hazard/community feedback clusters. Develop and maintain the database. Partners • Contra Costa County • Caltrans • CHP • CCTA • Member Agencies Timeline Within one year of plan adoption Performance Measures Assess surrogate safety measures and document KSI reductions; complete a full review of collision data to identify trends in 2035 93Contra Costa County Vision Zero Action Plan TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE 9. Meeting Date:11/08/2021   Subject:RECEIVE & consider public comments on the draft Flood Control Capital Improvement Plan for fiscal years 2021/2022 to 2027/2028. Submitted For: Brian M. Balbas, Public Works Director/Chief Engineer  Department:Public Works Referral No.: 7   Referral Name: Review issues associated with County flood control facilities.  Presenter: Gus Amirzehni, Department of Public Works Contact: Gus Amirzehni (925)313-2128 Referral History: On September 13, 2021, staff presented the draft Flood Control Capital Improvement Plan for fiscal years 2021/2022 to 2027/2028 (Plan) to the Transportation, Water and Infrastructure Committee. The Committee accepted the Plan, opened a public comment period, and scheduled this public meeting to receive and consider public comments on the Plan. The last Plan was accepted by the Transportation, Water and Infrastructure Committee on November 8, 2018, and adopted by the Board of Supervisors on December 11, 2018. The referral of the Plan to this Committee was approved by the Board of Supervisors on September 18, 2018. Referral Update: During the public comment period, the Plan was shared with community stakeholders and interested parties. A copy of the Plan was also made available for public review at the Contra Costa County Flood Control and Water Conservation District (District) Office and prominently featured on the District website. As of this writing, three information requests were received that resulted in staff offering assistance and providing information related to homeless encampment and localized flooding issues. One comment requested information about an existing project in the Plan. Another comment requested adding environmental enhancements to four Plan projects and adding two new projects for creek widening in Marsh Creek and flood risk reduction in Rheem Creek. The environmental enhancements are not excluded from the Plan and no action is needed. The creek widening project is part of a larger project included in the Plan and no action is needed. The flood risk reduction project will be evaluated and may be considered in future Plan updates. The Plan is a programming document for the funding of capital projects within the District within the next seven fiscal years. It is prepared and updated under the guidance of the District Expenditure Policy and is intended to be a living document updated every two years or as needed. Adoption of the Plan by the Board of Supervisors does not automatically approve capital projects listed in the Plan. Capital projects are subject to separate public review, engineering feasibility analysis, environmental assessment, and final approval by the Board of Supervisors. Recommendation(s)/Next Step(s): RECEIVE and consider public comments on the Plan, ACCEPT the Plan, and RECOMMEND adoption of the Plan by the Board of Supervisors, as the governing board of the District. Fiscal Impact (if any): The Plan recommends 29 projects within the District with a total cost of approximately $56 million over a seven-year period. Approximately $39 million is planned to be directly funded through various flood control funds with no impact to other County funds, and $13 million is planned to come from other local, State, or federal grants. As projects are developed, additional State and federal grants will be sought to augment District funds. Attachments Draft Plan FINAL DRAFT Flood Control Capital Improvement Plan 2021 Update Fiscal Year 2021/2022–2027/2028 CONTRA COSTA COUNTY FLOOD CONTROL AND WATER CONSERVATION DISTRICT 255 Glacier Drive Martinez, CA 94553 www.contracosta.ca.gov/5586/Flood-Control-District November 2021 2021 Flood Control Capital Improvement Plan (FINAL DRAFT) pg. ii TABLE OF CONTENTS 1. INTRODUCTION AND OVERVIEW .......................................................................................................... 1 2. FUNDING CHALLENGES AND PRIORITIES .............................................................................................. 1 3. REVENUE SOURCES ............................................................................................................................... 2 4. 2021 FLOOD CONTROL CAPITAL IMPROVEMENT PLAN........................................................................ 4 5. UNPROGRAMMED FUTURE PROJECTS.................................................................................................. 9 6. FUTURE UPDATES ................................................................................................................................. 9 7. CREDITS ............................................................................................................................................... 10 LIST OF FIGURES: Figure 1: 7-Year CIP Location Map Figure 2: 7-Year CIP Expenditure by Priority LIST OF TABLES: Table 1: 7-Year Flood Control CIP Overall Summary Table 2: 7-Year Flood Control CIP List Table 3: Unprogrammed Future Projects List APPENDICES: Appendix A: Detailed Project Information Appendix B: Unprogrammed Future Projects Details 2021 FLOOD CONTROL CAPITAL IMPROVEMENT PLAN 1. INTRODUCTION AND OVERVIEW The Flood Control Capital Improvement Plan (CIP) is a programming document for the funding of capital flood control projects within the Contra Costa County Flood Control and Water Conservation District (District). The District’s jurisdictional boundary covers the entire Contra Costa County and includes cities in addition to the unincorporated County communities. The flood control infrastructure includes 79 miles of flood control channels, 29 dams and detention basins, and 47 drop structures throughout the County. These facilities are on 4,189 parcels covering over 1,500 acres and provide the regional backbone of flood protection in Contra Costa County. The CIP is prepared in accordance with the District’s Expenditure Policy and presented to the Board of Supervisors for approval. This CIP is intended to be updated often, and it provides a 7-year outlook on the District’s capital activities in support of the regional, long-range development and related flood control plans. It is recognized that local communities have direct interest in the regional flood control projects and that those projects can impact a wide range of stakeholders. Therefore, the District is committed to developing projects in an open, community-based planning process. Furthermore, development of consistent stormwater management strategies in the region requires close coordination between local governments, regulators, as well as developers and landowners. The regional stormwater management strategies include concepts for comprehensive watershed management and resilient and sustainable design integration. To the extent feasible, those strategies and concepts have been incorporated into the development of this CIP. It is the intention of the District to continue to work collaboratively with all stakeholders to coordinate the implementation of regional drainage improvements. Approval of this CIP by the Board of Supervisors does not automatically approve projects for implementation. Flood control projects typically require years of advance planning, coordination, and cooperation between various agencies and community stakeholders. This CIP is prepared as a programmatic, planning-level document that intends to guide the District to program and initiate preliminary engineering work on the identified projects. Each project must undergo its own individual feasibility analysis and environmental assessment. As such, scope, schedule, and cost of each project is preliminary and may change after additional reviews. Some projects may later prove to be infeasible or not cost-effective and may be dropped from subsequent plans. 2. FUNDING CHALLENGES AND PRIORITIES Over the years, the District’s revenues have been constrained by fiscally-restrictive, statewide ballot measures, while the cost of operations and maintenance has increased significantly due to 2021 Flood Control Capital Improvement Plan (FINAL DRAFT) pg. 2 more stringent regulatory requirements and aging facilities. As a result, deferred maintenance has created over $39 million backlog of facility repair and restoration work throughout the District. In 2005, in response to these challenges and increasing demand for more capital improvements, the Board of Supervisors, as the governing Board of the District, established the Flood Control Expenditure Policy to provide overall fiscal programming direction and guidance to staff in developing the District’s capital improvement program. That Policy, generally, dictates that the District establish CIPs and give the highest priority to those projects that preserve the existing infrastructure and extend the useful life of a facility. 3. REVENUE SOURCES Funds for flood control improvements are mainly derived from property tax assessments, development and special benefit fees, and federal and state grants. Property tax and fee assessments are typically collected through various Flood Control Zones, Drainage Areas, and Benefit Assessment Areas. These zones and areas have been established throughout the District over the years. A map of established Drainage Areas and Drainage Zones is shown in Figure 1. The following provides a summary description of funding sources from those zones, areas, and other revenue sources: A. Flood Control Zone Property Tax Assessments Flood Control Zones were established over entire watersheds to fund the design, construction, and maintenance of flood control and water conservation facilities in the watershed. Funding resources vary from Zone to Zone with some Zones having no operating funds. In most cases, funding is not sufficient to maintain existing improvements, construct additional drainage facilities needed to provide the desired level of flood protection, or restore flood control channels to sustainable natural systems 1. There are 14 identified major watershed Flood Control Zones in the District. Ten Flood Control Zones have been formed, but only five generate tax revenue. B. Drainage Area Fees Drainage Areas were formed, as subwatersheds of Flood Control Zones, to provide funding for the construction of drainage improvements needed to mitigate increased storm runoff resulting from development within the subwatershed area2. Drainage Areas typically do not provide funding for ongoing maintenance of the DA improvements. There are 180 Drainage Areas identified in the District representing small watersheds or subwatersheds. Sixty-three of the Drainage Areas have been formed and have an adopted plan and a drainage fee ordinance. These are in areas where development has, is, or will be occurring. As such, revenues from these areas are dependent on the housing and land development economy. 1 Funding discrepancy between Zones is mainly due to Proposition 13, which effectively fixed property tax rates and constrained the District’s ability to raise new revenues. 2 Drainage Areas are analogous to the “Areas of Benefits” or “AOB” that collect revenues and fund transportation projects. kjkjkj kj kj kj kj kj kj kj kj kj kj kj kj kjkj kj kj kj kjkj kj kj kj kj kj kj kj {1}{3B} {2} {9} {7} {8} {12}{11}{6A} {8A} [5][3][1] [27] [10] [115] [139] [232] [227] [222][220] [218][217] [215] [213] [211] [210][209] [207] [130] [127] [122] [121] [118] [110] [109] [108] [107] [106] (108) (109) (55) (104) (56) (73) (107) (105) (46) (67) (9) (8) (10) (48B) (57) (106) (72) (13) (62) (128) (76) (30C) (52C) (89) (87)(30A) (33A) (30B) (75A) (47) (22) (101A) (29H)(40A) (48C) (16) (44B) (88) (52A) (29C) (33C) (78) (37A) (29J) (48D) (29G) (19A) (52B) (15A) (29E)(52D) (33B) (37A) Sources: Esri, HERE, DeLorme, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), swisstopo, MapmyIndia, © OpenStreetMap contributors, and the GIS U ser Community Leg end kj Project Locations [ID #] Dra inage Area s (DA#) Dra inage Zon es {DZ#} Contra Costa County Flo od C ontrol an d Wate r C onservation D istrict 7-Year CIP (2021-2028) Location Map ¯ 0 63 Miles Figure 1 kj kj kjkj{7} {6A} [5] [3] [1] [27] (19A) (73)3rdMarket 6thBrookside 5thParr 1stRichmond14th15thSilver 16th2ndRumrill17th7thPittsburg GiantD a v i l l a MartinFolsomCentral SotoClareRichmondkj kj kj kj kj{3B} [118] [109] [108] [107] [106] (89) (57) (87) (88) (72) (78)(16) (128)(62)I 680S ta te H w y 4 Ta y l o r D e tr oit Muir State Hwy 242WalkwayCenter I ron Hor se6th Contra CostaIdaP a c h e c o S alvioV i k i n g 5thK ik iMe a d o wBIm h o ffElli s P i n eMorelloAvon FStanwell3 r d 2021 Flood Control Capital Improvement Plan (FINAL DRAFT) pg. 4 C. Drainage Area Benefit Assessments Drainage Area Benefit Assessments (DABA) are funds that are typically used on operation, maintenance, and repair of storm drainage facilities in a defined drainage benefit assessment area. There are currently seven DABAs established in the District. D. Drainage Area Tax Assessments Three of the 63 formed Drainage Areas receive a small portion of tax revenue in addition to, or instead of, developer fees. Drainage Area property tax revenue is typically spent on the design, construction, operation, maintenance, repair, rehabilitation, and reconstruction of storm drainage facilities within the Drainage Area. E. Federal and State Grants The District has been successful in seeking and obtaining various state and federal grants for many of its projects in the recent past and continues to pursue those sources actively for future projects. In general, federal and state grants are becoming more competitive and very limited for single-purpose, flood control projects. This is a change from past decades when state and federal grants provided a majority of the District’s capital funding. Most grants now provide assistance to projects that provide grant-specific environmental benefits. This is another incentive for the District to incorporate environmental components to its flood control projects in order to be competitive with state and federal grants. 4. 2021 FLOOD CONTROL CAPITAL IMPROVEMENT PLAN In accordance with its Expenditure Policy, the District sets priorities within three specific program categories in establishing its capital program. These priorities are then balanced with the available funding in given Flood Control Zones or Drainage Areas to ensure the most feasible project delivery. The program categories in order of priority are: 1. System Preservation 2. Public Safety 3. System Expansion Based on the Expenditure Policy framework, a total of 29 projects representing an investment of over $56 million over seven years makeup this plan’s recommended projects. Figure 1 shows the geographic location of the proposed projects. Table 1 below provides an overall summary of recommended projects by funding entity highlighting project locations by watershed/major creek. Each location shown on the list may have several projects in various phases of development and implementation. It must be noted that some of the recommended projects are partially unfunded. Approximately $39 million is planned to be funded through various flood control funds and $13 million is planned to come from other local, State, or federal grants. An additional $4 million will be needed to fully 2021 Flood Control Capital Improvement Plan Table 1. 7-Year Flood Control Capital Improvement Overall Summary (By Fund Source/Creek) Funding Source/Creek FY 2021-22 FY 2022-23 FY 2023-24 FY 2024-25 FY 2025-26 FY 2026-27 FY 2027-28 Totals Flood Control Zone 1 200,000$ 130,000$ 180,000$ 360,000$ 468,000$ 1,640,000$ 420,000$ 3,398,000$ Dry -$ -$ -$ -$ -$ 140,000$ 210,000$ 350,000$ Marsh *200,000$ 130,000$ 180,000$ 360,000$ 468,000$ 1,500,000$ 210,000$ 3,048,000$ -$ Flood Control Zone 3B 695,000$ 5,066,000$ 5,220,000$ 2,830,000$ 190,000$ 20,000$ 40,000$ 14,061,000$ Galindo -$ -$ -$ -$ -$ 20,000$ 40,000$ 60,000$ Grayson *215,000$ 486,000$ 1,540,000$ 2,670,000$ -$ -$ -$ 4,911,000$ Grayson/Murderers *150,000$ -$ -$ -$ -$ -$ -$ 150,000$ Lower Walnut Creek 230,000$ 180,000$ 180,000$ -$ -$ -$ -$ 590,000$ Pine -$ -$ -$ 160,000$ 190,000$ -$ -$ 350,000$ Walnut 100,000$ 4,400,000$ 3,500,000$ -$ -$ -$ -$ Flood Control Zone 6A - San Pablo -$ 20,000$ -$ -$ 20,000$ -$ -$ 40,000$ Flood Control Zone 7 - Wildcat -$ 47,000$ -$ -$ 20,000$ -$ -$ 67,000$ Drainage Area 10 -$ 40,000$ 860,000$ 1,600,000$ -$ -$ -$ 2,500,000$ Drainage Area 13 -$ -$ 300,000$ 450,000$ -$ -$ -$ 750,000$ Drainage Area 46 - Grayson/Murderer's *-$ -$ -$ 528,000$ 626,000$ -$ -$ 1,154,000$ Drainage Area 56 - Antioch 200,000$ 200,000$ 1,067,000$ 817,000$ 99,000$ 102,000$ 102,000$ 2,587,000$ Drainage Area 73 50,000$ -$ -$ -$ -$ -$ -$ 50,000$ Drainage Area 130 102,000$ 91,000$ 187,000$ 227,000$ 1,936,000$ 6,359,750$ 5,758,750$ 14,661,500$ Deer 22,000$ 11,000$ 66,000$ 116,000$ 1,043,000$ 5,143,000$ -$ 6,401,000$ Marsh *-$ -$ -$ -$ 11,000$ 77,000$ 578,000$ 666,000$ Sand Creek 80,000$ 80,000$ 121,000$ 111,000$ 882,000$ 1,139,750$ 5,180,750$ 7,594,500$ Grants 9,596,585$ 1,286,585$ 1,205,585$ -$ -$ -$ -$ 12,088,755$ Lower Walnut Creek 9,335,000$ 1,025,000$ 944,000$ -$ -$ -$ -$ Wildcat 261,585$ 261,585$ 261,585$ -$ -$ -$ -$ Other - Grayson *140,000$ 146,000$ 900,000$ 100,000$ -$ -$ -$ 1,286,000$ Unfunded -$ 273,000$ -$ -$ 34,000$ 2,980,000$ 440,000$ 3,727,000$ Galindo -$ -$ -$ -$ -$ -$ 440,000$ 440,000$ Grayson/Murderer's -$ -$ -$ -$ 34,000$ -$ -$ 34,000$ Marsh -$ -$ -$ -$ -$ 2,980,000$ -$ 2,980,000$ Wildcat -$ 273,000$ -$ -$ -$ -$ -$ 273,000$ Totals 10,983,585$ 7,299,585$ 9,919,585$ 6,912,000$ 3,393,000$ 11,101,750$ 6,760,750$ 56,370,255$ * Multiple funding source. 2021 Flood Control Capital Improvement Plan (FINAL DRAFT) pg. 6 fund the projects. As projects are further developed, efforts will be made to seek additional resources. A more detailed list of all projects within each funding entity, including partially unfunded, is included in Table 2. As stated above, priorities set for each project are based on the framework outlined in the District’s Expenditure Policy. Approximately, 71% of planned capital expenditures will fund system preservation, while 28% will support system expansion in support of flood risk reduction. The remaining 1% will improve public safety. Figure 2 below shows the breakdown of capital expenditures by program priority. Figure 2. 7-Year CIP Expenditure by priority Additionally, detailed information about each project is included in Appendix A. The information provided for each project includes project name, description, justification, cost estimate, funding source(s), program priority, and anticipated expenditure plan category. Each project is assigned a unique number. Projects with numbers from 1 to 99 are located in West County, 100 to 199 are in Central County, and 200 and greater are in East County. Projects are presented in numerical order. Generally, all identified projects are led by the District; however, for the purpose of completeness, this CIP may include some projects that are co-funded by the District, but managed in partnership with other jurisdictions. It must be noted that in addition to capital projects, this CIP also includes several hydraulic, seismic, and condition assessment studies that support capital projects. System Preservation 71% System Expansion 28% Public Safety 1% 2021 Flood Control Capital Improvement Plan Table 2 Sheet 1 of 2 Table 2. 7-Year Flood Control Capital Improvement Project List (By Fund Source) Funding Source ID Project Title FY 2021-22 FY 2022-23 FY 2023-24 FY 2024-25 FY 2025-26 FY 2026-27 FY 2027-28 Totals Flood Control Zone 1 200,000$ 130,000$ 180,000$ 360,000$ 468,000$ 1,640,000$ 420,000$ 3,398,000$ 210 Marsh Creek Reservoir Seismic Assessment -$ 130,000$ 160,000$ -$ -$ -$ -$ 290,000$ 211 Dry Creek Reservoir Seismic Assessment -$ -$ -$ -$ -$ 140,000$ 210,000$ 350,000$ 213 Marsh Creek Reservoir Capacity and Habitat Restoration -$ -$ -$ 100,000$ 468,000$ 1,500,000$ 210,000$ 2,278,000$ 227 Flood Control Zone 1 Facilities Condition Assessment [8360]200,000$ -$ -$ -$ -$ -$ -$ 200,000$ 232 Marsh Creek Reservoir Emergency Spillway Rehabilitation -$ -$ 20,000$ 260,000$ -$ -$ -$ 280,000$ -$ Flood Control Zone 3B 695,000$ 5,066,000$ 5,220,000$ 2,830,000$ 190,000$ 20,000$ 40,000$ 14,061,000$ 107 Grayson and Walnut Creeks Levee Rehabilitation at CCCSD Treatment Plant 140,000$ 146,000$ 900,000$ 100,000$ -$ -$ -$ 1,286,000$ 108 Grayson Creek Channel Fence Rehabilitation -$ -$ -$ 600,000$ -$ -$ -$ 600,000$ 109 Grayson Creek Sediment Removal 75,000$ 340,000$ 640,000$ 1,970,000$ -$ -$ -$ 3,025,000$ 110 Lower Walnut Creek Restoration Project 230,000$ 180,000$ 180,000$ -$ -$ -$ -$ 590,000$ 118 Walnut Creek Sediment Removal - Clayton Valley Drain to Drop Structure 1 100,000$ 4,400,000$ 3,500,000$ -$ -$ -$ -$ 8,000,000$ 121 Kubicek Basin Sediment Removal -$ -$ -$ 50,000$ -$ -$ -$ 50,000$ 122 Pine Creek Dam Seismic Assessment -$ -$ -$ 110,000$ 190,000$ -$ -$ 300,000$ 127 Galindo Creek Improvements -$ -$ -$ -$ -$ 20,000$ 40,000$ 60,000$ 130 Flood Control Zone 3B Channels and Structures Conditions Assessment 150,000$ -$ -$ -$ -$ -$ -$ 150,000$ -$ Flood Control Zone 6A -$ 20,000$ -$ -$ 20,000$ -$ -$ 40,000$ 1 San Pablo Creek Silt Survey -$ 20,000$ -$ -$ 20,000$ -$ -$ 40,000$ Flood Control Zone 7 -$ 47,000$ -$ -$ 20,000$ -$ -$ 67,000$ 3 Wildcat Creek Silt Survey $0 $20,000 $0 $0 $20,000 $0 $0 40,000$ 5 Wildcat Sediment Basin Desilt $0 $27,000 $0 $0 $0 $0 $0 -$ Drainage Area 10 -$ 40,000$ 860,000$ 1,600,000$ -$ -$ -$ 2,500,000$ DA 10 Facility Improvements -$ 40,000$ 860,000$ 1,600,000$ -$ -$ -$ -$ Drainage Area 13 -$ -$ 300,000$ 450,000$ -$ -$ -$ 750,000$ 139 DA 13 Line F-1 Storm Drainage in Alamo -$ -$ 300,000$ 450,000$ -$ -$ -$ 750,000$ -$ Drainage Area 46 -$ -$ -$ 528,000$ 626,000$ -$ -$ 1,154,000$ 106 DA46 Grayson and Murderer's Creek Subregional Improvements -$ -$ -$ 528,000$ 626,000$ -$ -$ -$ Drainage Area 56 200,000$ 200,000$ 1,067,000$ 817,000$ 99,000$ 102,000$ 102,000$ 2,587,000$ 207 Trembath Detention Basin 200,000$ 200,000$ 1,050,000$ 800,000$ -$ -$ -$ 2,250,000$ 209 Develop Revenue Generating Sites at Lindsey Basin -$ -$ 17,000$ 17,000$ 99,000$ 102,000$ 102,000$ 337,000$ 2021 Flood Control Capital Improvement Plan Table 2 Sheet 2 of 2 Funding Source ID Project Title FY 2021-22 FY 2022-23 FY 2023-24 FY 2024-25 FY 2025-26 FY 2026-27 FY 2027-28 Totals -$ Drainage Area 73 50,000$ -$ -$ -$ -$ -$ -$ 50,000$ 10 DA 73 Drainage Plan Update - Richmond 50,000$ -$ -$ -$ -$ -$ -$ -$ Drainage Area 130 102,000$ 91,000$ 187,000$ 227,000$ 1,936,000$ 6,359,750$ 5,758,750$ 14,661,500$ 215 Marsh Creek Supplemental Capacity -$ -$ -$ -$ 11,000$ 77,000$ 578,000$ 666,000$ 217 Deer Creek Reservoir Expansion 22,000$ 11,000$ 66,000$ 88,000$ 894,000$ 5,143,000$ -$ 6,224,000$ 218 Deer Creek Reservoir Expansion - R/W Acquisition -$ -$ -$ 28,000$ 149,000$ -$ -$ 177,000$ 220 Upper Sand Creek Basin Surplus Material 60,000$ 60,000$ 60,000$ -$ -$ -$ -$ 180,000$ 222 Lower Sand Creek Basin Construction 20,000$ 20,000$ 61,000$ 111,000$ 882,000$ 1,139,750$ 5,180,750$ 7,414,500$ -$ Grants 9,596,585$ 1,286,585$ 1,205,585$ -$ -$ -$ -$ 12,088,755$ 110 Lower Walnut Creek Restoration Project 9,335,000$ 1,025,000$ 944,000$ -$ -$ -$ -$ 11,304,000$ 27 Wildcat Creek Fish Passage and Community Engagement -- Phase I 261,585$ 261,585$ 261,585$ -$ -$ -$ -$ 784,755$ Other 140,000$ 146,000$ 900,000$ 100,000$ -$ -$ -$ 1,286,000$ 107 Grayson and Walnut Creeks Levee Rehabilitation at CCCSD Treatment Plant 140,000$ 146,000$ 900,000$ 100,000$ -$ -$ -$ 1,286,000$ Unfunded -$ 273,000$ -$ -$ 34,000$ 2,980,000$ 440,000$ 3,727,000$ 5 Wildcat Sediment Basin Desilt -$ 273,000$ -$ -$ -$ -$ -$ 273,000$ 106 DA46 Grayson and Murderer's Creek Subregional Improvements -$ -$ -$ -$ 34,000$ -$ -$ 34,000$ 127 Galindo Creek Improvements -$ -$ -$ -$ -$ -$ 440,000$ 440,000$ 213 Marsh Creek Reservoir Capacity and Habitat Restoration -$ -$ -$ -$ -$ 2,980,000$ -$ 2,980,000$ Totals 10,983,585$ 7,299,585$ 9,919,585$ 6,912,000$ 3,393,000$ 11,101,750$ 6,760,750$ 56,370,255$ 2021 Flood Control Capital Improvement Plan (FINAL DRAFT) pg. 9 5. UNPROGRAMMED FUTURE PROJECTS Unprogrammed future projects are those that have been scoped, but not yet programmed for funding in the next 7 years. Those projects are expected to be included in future plans for implementation after 2028. Table 3 includes a list of future projects. Details of these projects are included in Appendix B. Table 3. Unprogrammed Future Projects 6. FUTURE UPDATES This CIP is intended to be updated every two years or as needed to provide a multi-year outlook on the District’s capital activities. The next update is expected to be published in two years. Funding Source ID Project Title Cost Flood Control Zone 3B 15,500,000$ 124 Pine Creek Reservoir Sediment Removal and Capacity Restoration 5,500,000$ 125 San Ramon Creek Sediment Removal near San Ramon Bypass 400,000$ 128 Green Valley Creek Improvements up to 1st Crossing of Diablo Road 7,300,000$ 129 Green Valley Creek Improvements Upstream of 2nd Crossing of Diablo Road 2,300,000$ Drainage Area 33A 200,000$ 120 DA 33A Concord Boulevard Culvert Replacement 200,000$ Drainage Area 48B 490,000$ 201 DA 48B Line A at Port Chicago Highway 490,000$ Drainage Area 55 255,000$ 205 Fitzuren Road Remainder Parcel 255,000$ Drainage Area 109 300,000$ 225 DA 109 - Kellogg Creek Project Development 300,000$ Unfunded 57,506,000$ 9 Wildcat / San Pablo Creeks Phase II 13,250,000$ 12 Pinole Creek Habitat Restoration (1135 Project)6,875,000$ 17 Sustainable Capacity Improvement at Rodeo Creek 11,315,000$ 23 Canada di Cierbo Habitat Improvement 3,500,000$ 26 Pinole Creek Capacity Assessment 350,000$ 117 DA 67 - Tice Creek Bypass 2,730,000$ 120 DA 33A Concord Boulevard Culvert Replacement 150,000$ 203 West Antioch Creek Improvements - L Street to 10th Street 5,466,000$ 204 West Antioch Creek Improvements at Highway 4 2,500,000$ 206 East Antioch Creek Marsh Restoration 11,370,000$ Total: 74,251,000$ 2021 Flood Control Capital Improvement Plan (FINAL DRAFT) pg. 10 7. CREDITS Prepared By: Gus Amirzehni, PE Reviewed By: Paul Detjens, PE List of Appendices: Appendix A: Detailed Project Information Sheets Appendix B: Unprogrammed Future Projects Details Appendix A Detailed Project Information CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:San Pablo Creek Silt Survey WORK ORDER:WO TBD PROJECT DESCRIPTION:Perform focused topographic surveys at six predesignated cross section locations to determine the amount of sediment accumulation and to determine the need for channel desilting. Channel desilting, once determined to be needed, would be scoped under a separate CIP entity. PROJECT NEED:The current operations and maintenance manual produced by the Corps requires annual sediment surveys. These surveys are a method to determine channel capacity and are in lieu of a more comprehensive survey and hydraulic model. SUPERVISOR DISTRICT:I AFFECTED AREA:Richmond, North Richmond PROGRAM TYPE:System Preservation PROJECT PRIORITY:4 FUNDING SOURCE(S):Flood Control Zone 6 TOTAL PROJECT COST:$40,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $20,000 $0 $0 $20,000 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:1 Flood Control Zone 6A $0 $20,000 $0 $0 $20,000 $0 $0 November 2021 1 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Wildcat Creek Silt Survey WORK ORDER:9705 PROJECT DESCRIPTION:Perform focused topographic surveys at six predesignated cross section locations to determine the amount of sediment accumulation and to determine the need for channel desilting. Channel desilting, once determined to be needed, would be scoped under a separate CIP entity. PROJECT NEED:The current operations and maintenance manual produced by the Corps requires annual sediment surveys. These surveys are a method to determine channel capacity and are in lieu of a more comprehensive survey and hydraulic model. SUPERVISOR DISTRICT:I AFFECTED AREA:Richmond PROGRAM TYPE:System Preservation PROJECT PRIORITY:4 FUNDING SOURCE(S):FC Zone 7, TBD TOTAL PROJECT COST:$40,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $20,000 $0 $0 $20,000 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:3 Flood Control Zone 7 $0 $20,000 $0 $0 $20,000 $0 $0 November 2021 2 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Wildcat Sediment Basin Desilt WORK ORDER:WO TBD PROJECT DESCRIPTION:Remove accumulated sediment from the Wildcat Creek Sediment Basin and stockpile on adjacent storage site for later off haul. PROJECT NEED:The Wildcat Creek sediment basin is designed to trap sediment and prevent sediment accumulation in more sensitive areas downstream. If it is not periodically desilted, the basin becomes less effective and sediment escapes downstream. SUPERVISOR DISTRICT:I AFFECTED AREA:Richmond PROGRAM TYPE:System Preservation PROJECT PRIORITY:2 FUNDING SOURCE(S):Flood Control Zone 7, Unfunded TOTAL PROJECT COST:$900,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:Basin was last desilted in 2010-2011. $0 $300,000 $0 $0 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:5 Flood Control Zone 7 $0 $27,000 $0 $0 $0 $0 $0 Unfunded $0 $273,000 $0 $0 $0 $0 $0 November 2021 3 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:DA 73 Drainage Plan Update - Richmond WORK ORDER:WO TBD PROJECT DESCRIPTION:Update the Drainage Area 73 Drainage Plan to reflect community needs PROJECT NEED:Drainage Area 73 has an outdated plan, and it does not reflect current drainage needs. In collaboration with the City of Richmond and community stakeholders, this project will develop an updated drainage plan and a list of drainage projects to accommodate current drainage needs. SUPERVISOR DISTRICT:I AFFECTED AREA:Richmond PROGRAM TYPE:Public Safety PROJECT PRIORITY:3 FUNDING SOURCE(S):Drainage Area 73 TOTAL PROJECT COST:$50,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $50,000 $0 $0 $0 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:10 Drainage Area 73 $50,000 $0 $0 $0 $0 $0 $0 November 2021 4 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Wildcat Creek Fish Passage and Community Engagement -- Phase I WORK ORDER:8101 PROJECT DESCRIPTION:Phase 1 of the project is to finalize design and complete CEQA and permitting process to retrofit the existing fish ladder/sedimentation basin to meet CDFW fish passage criteria for anadromous fish species, and to provide a facility that is less likely to clog due to heavy sediment load and trash. Additionally, the proejct will include a modification to a channel control structure to reduce flood risk and a community outreach to raise awareness in the community. PROJECT NEED:The Lower Wildcat Creek Flood Control Channel includes a low flow channel and fish ladder. In 2000 recognizing design deficiencies in the ladder, a Section 1135 investigation was initiated by the ACOE Waterways Experiment Station which ultimately led in 2014 to a preliminary retro-fit design conducted by Northwest Hydraulics Consultants (NHC). This project will develop the final construction documents and 100% PS&E for the fish ladder and sediment basin modofications based on the preliminary design developed by NHC. SUPERVISOR DISTRICT:I AFFECTED AREA:North Richmond PROGRAM TYPE:System Preservation PROJECT PRIORITY:1 FUNDING SOURCE(S):California DWR USRP Grant TOTAL PROJECT COST:$784,775 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):N NOTE:Funding provided by the California Department of Water Resources, Urban Streams Restorration Program grant awarded in 2021. $261,585 $261,585 $261,585 $0 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:27 Grants $261,585 $261,585 $261,585 $0 $0 $0 $0 November 2021 5 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:DA46 Grayson and Murderer's Creek Subregional Improvements WORK ORDER:TBD PROJECT DESCRIPTION:In partnership with the City of Pleasant Hill, the project will identify, design and implement sub-regional drainage improvements in the Grayson / Murderer's Creeks subwatershed. Likely projects are capacity improvements at bridges, floodwalls along sections of creek, and collector storm drains to more efficiently deliver stormwater to the creek. PROJECT NEED:Downtown Pleasant Hill and Poet's Corner areas are identified on the FEMA maps as having moderate flood risk. Area flooded in 1997 and again in 2006. City desires a project to take residents out of the floodplain. Early indications from the Corps study were favorable, but project ultimately did not have a sufficient benefit / cost ratio, or federal funding. This local, smaller project is the result. SUPERVISOR DISTRICT:IV AFFECTED AREA:Pleasant Hill PROGRAM TYPE:System Expansion PROJECT PRIORITY:2 FUNDING SOURCE(S):Drainage Area 46 funds + City of Pleasant Hill funds TOTAL PROJECT COST:$1,188,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:DA46 plan amendment needed before implementation of this project. $0 $0 $0 $528,000 $660,000 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:106 Drainage Area 46 $0 $0 $0 $528,000 $626,000 $0 $0 Unfunded $0 $0 $0 $0 $34,000 $0 $0 November 2021 6 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Grayson and Walnut Creeks Levee Rehabilitation at CCCSD Treatment Plant WORK ORDER:8348 PROJECT DESCRIPTION:Raise levees along Grayson Creek along STA 8+00 to 39+00 LT and Walnut Creek along STA 137+62 to 185+35 to improve level of protection at CCCSD treatment plant. PROJECT NEED:Additional flood protection is desired at the CCCSD Treatment Plant from Grayson Creek and Walnut Creek. This is in addition to the 2007 project that increased flood protection to a 100-year design storm level. SUPERVISOR DISTRICT:V AFFECTED AREA:Martinez area, Unincorporated County PROGRAM TYPE:System Preservation PROJECT PRIORITY:1 FUNDING SOURCE(S):Flood Control Zone 3B and CCCSD TOTAL PROJECT COST:$2,572,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $280,000 $292,000 $1,800,000 $200,000 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:107 Flood Control Zone 3B $140,000 $146,000 $900,000 $100,000 $0 $0 $0 Other $140,000 $146,000 $900,000 $100,000 $0 $0 $0 November 2021 7 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Grayson Creek Channel Fence Rehabilitation WORK ORDER:WO TBD PROJECT DESCRIPTION:Repair Fences along Grayson Creek concrete channel as part of our Creek and Channel Safety Program PROJECT NEED:Existing fence posts are starting to rust and spalling concrete from the channel wall. This project would renovate existing fence posts and fence, rehabilitate the damaged concrete wall, and replace the failing fence with new material. This project would extend the useful life of the protective fenceline, as well as preventing further deterioration of the concrete wall as part of our Creek and Channel Safety Program. SUPERVISOR DISTRICT:IV AFFECTED AREA:Pleasant Hill PROGRAM TYPE:Public Safety PROJECT PRIORITY:3 FUNDING SOURCE(S):Flood Control Zone 3B TOTAL PROJECT COST:$600,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $600,000 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:108 Flood Control Zone 3B $0 $0 $0 $600,000 $0 $0 $0 November 2021 8 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Grayson Creek Sediment Removal WORK ORDER:8334 PROJECT DESCRIPTION:Remove accumulated sediment from Grayson creek between confluence with Walnut Creek to Chilpancingo Parkway (about 9,000 linear feet in selected areas) PROJECT NEED:Remove accumulated sediment to restore design flood capacity of the channel. Exact areas to be desilted will be determined with a pre-design topographic silt survey. SUPERVISOR DISTRICT:IV & V AFFECTED AREA:Pleasant Hill, Pacheco PROGRAM TYPE:System Preservation PROJECT PRIORITY:1 FUNDING SOURCE(S):Flood Control Zone 3B TOTAL PROJECT COST:$3,025,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:Portions of this area was last desilted in 2006. Effort shared with Walnut Creek desilt (#118) $75,000 $340,000 $640,000 $1,970,000 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:109 Flood Control Zone 3B $75,000 $340,000 $640,000 $1,970,000 $0 $0 $0 November 2021 9 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Lower Walnut Creek Restoration Project WORK ORDER:8285 PROJECT DESCRIPTION:Transform Lower Walnut Creek from an antiquated, difficult to maintain, legacy USACE facility into a sustainable, environmentally sensitive facility for the next 50 years. Project includes modification of project levees, acquisition of flowage easements and possible reconfiguration of the channel conveyance to better accommodate sediment and habitat. PROJECT NEED:The Lower Walnut Creek project incorporates a new way of approaching the traditional methods of operating and maintaining a flood control facility. This alternative approach moves away from the single purpose, flood protection USACE design, to a sustainable, environmentally sensitive plan that will restore appropriate floodplains and habitat in the area. SUPERVISOR DISTRICT:V AFFECTED AREA:Martinez, Pacheco, Concord PROGRAM TYPE:System Preservation PROJECT PRIORITY:1 FUNDING SOURCE(S):Flood Control Zone 3B and Regional, State and federal Grant Funds (TBD) TOTAL PROJECT COST:$41,630,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:Signature District project. Prior and future year expenditures not shown. Existing grants received from CDFW and EPA. Anticipated future grants to cover unfunded. $9,565,000 $1,205,000 $1,124,000 $0 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:110 Flood Control Zone 3B $230,000 $180,000 $180,000 $0 $0 $0 $0 Grants $9,335,000 $1,025,000 $944,000 $0 $0 $0 $0 Unfunded $0 $0 $0 $0 $0 $0 $0 November 2021 10 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:DA 10 Facility Improvements WORK ORDER: PROJECT DESCRIPTION:Construct facility improvements along existing drainage lines in order to reduce local flooding risk. Line F improvement recommendations include installing 185 feet of 27-inch pipe and 530 feet of 24-inch pipe to existing drainage pipe to improve conveyance of stormwater from the community between Calmar Vista Road and Danville Boulevard. Line A improvement recommendations include installing retaining walls along 410 feet of earthen channel near Montair Elementary School to minimize bank failure. Line A and A-5 improvement recommendations include installing multiple low-level weirs along the 1,570 feet of earthen channel upstream ofthe retaining walls to capture silt before it can collect in downstream pipes. PROJECT NEED:Improvement recommendations are based on a review of the existing and propsoed DA facilities, several site visits, and input from the Town of Danville to improve drainage conditions in the area. SUPERVISOR DISTRICT:II AFFECTED AREA:Danville PROGRAM TYPE:System Expansion PROJECT PRIORITY:3 FUNDING SOURCE(S):Drainage Area 10 TOTAL PROJECT COST:$2,500,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $40,000 $860,000 $1,600,000 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:115 Drainage Area 10 $0 $40,000 $860,000 $1,600,000 $0 $0 $0 November 2021 11 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Walnut Creek Sediment Removal - Clayton Valley Drain to Drop Structure 1 WORK ORDER:8334 PROJECT DESCRIPTION:Remove accumulated sediment from upland benches in Walnut Creek to restore channel capacity and restore wetlands PROJECT NEED:Remove accumulated sediment to restore design flood capacity of the channel. Exact areas to be desilted will be determined with a pre-design topographic silt survey. SUPERVISOR DISTRICT:IV AFFECTED AREA:Concord, Pleasant Hill PROGRAM TYPE:System Preservation PROJECT PRIORITY:1 FUNDING SOURCE(S):Flood Control Zone 3B TOTAL PROJECT COST:$8,000,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:Effort shared with Grayson desilt (#109) $100,000 $4,400,000 $3,500,000 $0 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:118 Flood Control Zone 3B $100,000 $4,400,000 $3,500,000 $0 $0 $0 $0 November 2021 12 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Kubicek Basin Sediment Removal WORK ORDER:WO TBD PROJECT DESCRIPTION:Remove sediment and restore habitat to ensure basin continues to function as designed PROJECT NEED:The Pine Creek Detention Basin -- now known as the Kubicek Basin -- was designed for sediment storage. This sediment needs to be periodically removed to ensure proper functioning of the basin. Sediment has not been removed since the basin was constructed in the 1970s. SUPERVISOR DISTRICT:IV AFFECTED AREA:Walnut Creek, Concord PROGRAM TYPE:System Preservation PROJECT PRIORITY:3 FUNDING SOURCE(S):Flood Control Zone 3B TOTAL PROJECT COST:$50,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:Prior year expenditures not shown. $0 $0 $0 $50,000 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:121 Flood Control Zone 3B $0 $0 $0 $50,000 $0 $0 $0 November 2021 13 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Pine Creek Dam Seismic Assessment WORK ORDER:8346 PROJECT DESCRIPTION:Hire specialized consultant to assess seismic performance of existing dam and recommend retrofit improvements. Two-phase approach: start with hazard assessment, and proceed to more detailed geotechnical analysis if warranted. PROJECT NEED:This project would identify deficiencies and conduct a retrofit plan, if needed. SUPERVISOR DISTRICT:IV AFFECTED AREA:Walnut Creek, Unincorporated County PROGRAM TYPE:System Preservation PROJECT PRIORITY:3 FUNDING SOURCE(S):Flood Control Zone 3B TOTAL PROJECT COST:$300,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $110,000 $190,000 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:122 Flood Control Zone 3B $0 $0 $0 $110,000 $190,000 $0 $0 November 2021 14 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Galindo Creek Improvements WORK ORDER:WO TBD PROJECT DESCRIPTION:Participate with City of Concord and USACE to construct a stormwater detention basin on Galindo Creek upstream of Ygnacio Valley Road (CSU East Bay Campus). Basin will be created with a modification to the existing headwall. PROJECT NEED:This project would reduce flood risk to properties in the floodplain between Ygnacio Valley and the start of the concrete channel portion of Galindo Creek in the City of Concord. USACE and Concord have completed a federal reconnaissance study. SUPERVISOR DISTRICT:IV AFFECTED AREA:Concord PROGRAM TYPE:System Expansion PROJECT PRIORITY:5 FUNDING SOURCE(S):Flood Control Zone 3B and the City of Concord TOTAL PROJECT COST:$500,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:Assume Concord will be the lead agency for CEQA/permits. Expect larger total project with additional funding by other partners. $500k is max FC Zone 3B contribution. $0 $0 $0 $0 $0 $20,000 $480,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:127 Flood Control Zone 3B $0 $0 $0 $0 $0 $20,000 $40,000 Unfunded $0 $0 $0 $0 $0 $0 $440,000 November 2021 15 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Flood Control Zone 3B Channels and Structures Conditions Assessment WORK ORDER:8353 PROJECT DESCRIPTION:Hire specialized consultants to assess conditions of existing facilities. Two-phase approach: start with initial assessment, and proceed to more detailed assessment as warranted. PROJECT NEED:Need to identify deficiencies and conduct a retrofit plan, if needed. SUPERVISOR DISTRICT:IV & V AFFECTED AREA:Pleasant Hill, Walnut Creek, Concord, and unincorporated. PROGRAM TYPE:System Preservation PROJECT PRIORITY:1 FUNDING SOURCE(S):Flood Control Zone 3B TOTAL PROJECT COST:$915,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $150,000 $0 $0 $0 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:130 Flood Control Zone 3B $150,000 $0 $0 $0 $0 $0 $0 November 2021 16 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:DA 13 Line F-1 Storm Drainage in Alamo WORK ORDER:8303 PROJECT DESCRIPTION:Construct a drainage line that will connect with the existing drainage network and reduce local flooding issues. The newly created drainage line (Line F-1) will consist of a 30-inch pipe that will run parallel to the Iron Horse Trail Corridor from existing line “F” at Las Trampas Road (1300 ft.), to the intersection of South Avenue. From this point the pipe will extend another 150 ft. to the southwest, to the intersection of South Avenue and La Serena Court (Fig.1). Drainage inlet structures will be placed every 250 feet (as per the County criteria) including: 6 inlets on the Iron Horse Trail, 1 manhole on Las Trampas Road, and 2 inlets in the intersection of South Avenue and La Serena Court. PROJECT NEED:To address recurring flooding complications at locations along South Avenue; the intersection of South Avenue and Wayland Lane, and the intersection of South Avenue and La Serena Court. SUPERVISOR DISTRICT:II AFFECTED AREA:Alamo PROGRAM TYPE:System Expansion PROJECT PRIORITY:2 FUNDING SOURCE(S):Drainage Area 13 TOTAL PROJECT COST:$750,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $300,000 $450,000 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:139 Drainage Area 13 $0 $0 $300,000 $450,000 $0 $0 $0 November 2021 17 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Trembath Detention Basin WORK ORDER:8532 PROJECT DESCRIPTION:Design and construct Trembath Detention Basin. Trembath Basin is a new facility. Trembath Basin will be regulated by State Division of Dam Safety. PROJECT NEED:This project is needed to provide flood protection in the lower watershed of East Antioch Creek in accordance with the adopted Drainage Area 56 (DA 56) plan. SUPERVISOR DISTRICT:III AFFECTED AREA:Antioch PROGRAM TYPE:System Expansion PROJECT PRIORITY:2 FUNDING SOURCE(S):Drainage Area 56 (Org 7566) TOTAL PROJECT COST:$12,550,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):YES NOTE:Prior and future year expenditures not shown. $200,000 $200,000 $1,050,000 $800,000 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:207 Drainage Area 56 $200,000 $200,000 $1,050,000 $800,000 $0 $0 $0 November 2021 18 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Develop Revenue Generating Sites at Lindsey Basin WORK ORDER:WO TBD PROJECT DESCRIPTION:Prepare conceptual plans and a cost estimate for the development of the two District-owned remainder parcels near the Lindsey Basin. Market the parcels to generate maximum long-term revenue for the Drainage Area and / or the District. PROJECT NEED:The Lindsey Detention Basin was designed for future re-use of spoil disposal sites as revenue-generating development. This project will facilitate this long-planned development. Project timing is a rough estimate; actual development depends on the commercial real estate market. SUPERVISOR DISTRICT:III AFFECTED AREA:Antioch PROGRAM TYPE:System Preservation PROJECT PRIORITY:5 FUNDING SOURCE(S):Drainage Area funds (Org,7566) TOTAL PROJECT COST:$593,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:Future year expenditures not shown. $0 $0 $17,000 $17,000 $99,000 $102,000 $102,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:209 Drainage Area 56 $0 $0 $17,000 $17,000 $99,000 $102,000 $102,000 November 2021 19 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Marsh Creek Reservoir Seismic Assessment WORK ORDER:8355 PROJECT DESCRIPTION:Hire specialized consultant to assess seismic performance of existing dam and recommend retrofit improvements, if needed. Two-phase approach: start with hazard assessment, and proceed to more detailed geotechnical analysis if warranted. PROJECT NEED:Need to identify deficiencies and conduct a retrofit plan, if needed. SUPERVISOR DISTRICT:III AFFECTED AREA:Brentwood PROGRAM TYPE:System Preservation PROJECT PRIORITY:3 FUNDING SOURCE(S):Flood Control Zone 1 TOTAL PROJECT COST:$330,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):YES NOTE: $0 $130,000 $160,000 $0 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:210 Flood Control Zone 1 $0 $130,000 $160,000 $0 $0 $0 $0 November 2021 20 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Dry Creek Reservoir Seismic Assessment WORK ORDER:WO TBD PROJECT DESCRIPTION:Hire specialized consultant to assess seismic performance of existing dam embankments and recommend retrofit improvements, if needed. Two-phase approach: start with hazard assessment, and proceed to more detailed geotechnical analysis if warranted. PROJECT NEED:Need to identify deficiencies and conduct a retrofit plan, if needed. SUPERVISOR DISTRICT:III AFFECTED AREA:Brentwood PROGRAM TYPE:System Preservation PROJECT PRIORITY:3 FUNDING SOURCE(S):Flood Control Zone 1 TOTAL PROJECT COST:$360,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):YES NOTE: $0 $0 $0 $0 $0 $140,000 $210,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:211 Flood Control Zone 1 $0 $0 $0 $0 $0 $140,000 $210,000 November 2021 21 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Marsh Creek Reservoir Capacity and Habitat Restoration WORK ORDER:8495 PROJECT DESCRIPTION:Assess reservoir condition and habitat condition of impoundment area. Develop restoration plan that: maintains or improves level of flood protection, improves surrounding habitat, is compatible with surrounding state park uses, deals appropriately with accumulated mercury and accommodates mercury that will arrive at the basin in the next 50 years. After proper approvals and CEQA analysis, implement the preferred alternative. PROJECT NEED:Marsh Creek Reservoir was constructed in 1964 as a single-purpose facility and has reduced flood risks. Now nearing a half-century of use, the reservoir has poor water quality (impacted by mercury). With the opening of the state park on surrounding lands, there is an increased pressure to allow public access. A comprehensive restoration plan is needed to guide operations of this facility and development of future projects for the next 50 years. SUPERVISOR DISTRICT:III AFFECTED AREA:Oakley, Brentwood PROGRAM TYPE:System Preservation PROJECT PRIORITY:3 FUNDING SOURCE(S):Flood Control Zone 1, future grant funds TOTAL PROJECT COST:$5,400,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):Yes NOTE:Plan implementation may be delayed depending on other priorities for FC Zone 1 funds, (Future year expenditures not shown.) $0 $0 $0 $100,000 $468,000 $4,480,000 $210,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:213 Flood Control Zone 1 $0 $0 $0 $100,000 $468,000 $1,500,000 $210,000 Unfunded $0 $0 $0 $0 $0 $2,980,000 $0 November 2021 22 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Marsh Creek Supplemental Capacity WORK ORDER:WO TBD PROJECT DESCRIPTION:Raise channel banks, levees and construct floodwalls to improve flood protection PROJECT NEED:A 2010 District study identified the need for additional channel capacity upon ultimate development of the watershed. This project is needed to ensure 100-year storms are contained in the channel without overtopping and flooding adjacent neighborhoods. SUPERVISOR DISTRICT:III AFFECTED AREA:Oakley, Brentwood PROGRAM TYPE:System Expansion PROJECT PRIORITY:3 FUNDING SOURCE(S):Flood Control Zone 1, Drainage Area 130, future grant funds TOTAL PROJECT COST:$3,664,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):YES NOTE:See the 2010 study on file to contain 100-year flood flows and contain 50-year flood flows with freeboard. (Future year expenditures not shown.) $0 $0 $0 $0 $11,000 $77,000 $578,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:215 Drainage Area 130 $0 $0 $0 $0 $11,000 $77,000 $578,000 November 2021 23 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Deer Creek Reservoir Expansion WORK ORDER:8447 PROJECT DESCRIPTION:Excavate the storage area of the existing Deer Creek Reservoir to increase stormwater holding capacity and reduce flood flows downstream PROJECT NEED:This project would increase storage capacity of Deer Creek Reservoir to protect downstream properties from flooding. Work to date has established that it is more beneficial to expand the future storage volume behind the existing dam by selectively excavating the storage area rather than raising the dam. SUPERVISOR DISTRICT:III AFFECTED AREA:Oakley, Brentwood PROGRAM TYPE:System Preservation PROJECT PRIORITY:3 FUNDING SOURCE(S):Drainage Area 130, possible Flood Control Zone 1 TOTAL PROJECT COST:$6,230,600 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):YES NOTE: $22,000 $11,000 $66,000 $88,000 $894,000 $5,143,000 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:217 Drainage Area 130 $22,000 $11,000 $66,000 $88,000 $894,000 $5,143,000 $0 November 2021 24 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Deer Creek Reservoir Expansion - R/W Acquisition WORK ORDER:8463 PROJECT DESCRIPTION:Acquire additional land rights over area currently encumbered only by a flowage easement. This is needed for expansion of the storage area of the Deer Creek Reservoir, located south of Balfour Road in Brentwood. PROJECT NEED:Need to retain additional stormwater in Deer Creek Reservoir to protect downstream properties. Instead of raising the dam, the plan is to expand the storage volume behind the existing dam by selectively excavating the storage area. The existing flowage easement is insufficient to do so; need to upgrade flowage easement into a drainage easement. SUPERVISOR DISTRICT:III AFFECTED AREA:Brentwood PROGRAM TYPE:System Preservation PROJECT PRIORITY:3 FUNDING SOURCE(S):Drainage Area 130, possible Flood Control Zone 1 TOTAL PROJECT COST:$214,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):N/A NOTE: $0 $0 $0 $28,000 $149,000 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:218 Drainage Area 130 $0 $0 $0 $28,000 $149,000 $0 $0 November 2021 25 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Upper Sand Creek Basin Surplus Material WORK ORDER:8517 PROJECT DESCRIPTION:Coordinate removal of Upper Sand Creek Basin material by others, separate from main USCB contract. Includes material removed in advance of construction as well as material removed post construction. Common customers include contractors, developers and other agencies needing high quality fill material. PROJECT NEED:Brokering dirt removal in this way typically represents an excellent value (in cost/yd3) for the District. Interest in material (and thus cost) is highly dependent on the economy. Each cubic yard of material removed gets the basin incrementally closer to its ultimate volume at a reduced cost per cubic yard. SUPERVISOR DISTRICT:III AFFECTED AREA:Antioch PROGRAM TYPE:System Expansion PROJECT PRIORITY:2 FUNDING SOURCE(S):DA 130, FC Zone 1 TOTAL PROJECT COST:$180,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):YES NOTE:Prior and future expenditures not shown. $60,000 $60,000 $60,000 $0 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:220 Drainage Area 130 $60,000 $60,000 $60,000 $0 $0 $0 $0 November 2021 26 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Lower Sand Creek Basin Construction WORK ORDER:8492 PROJECT DESCRIPTION:Construct a 300 ac-ft regional detention basin on Sand Creek. The existing 40 ac-ft basin will be converted into an 300 ac-ft offline basin with new intake structure, primary and emergency spillways, low flow channel and riparian mitigation area. PROJECT NEED:In conjunction with the Upper Sand Creek Basin, this lower basin will reduce stormwater flows in Sand Creek and in Marsh Creek. With the upper basin in place, the 100 year 12 hour flow rate is 1230 cfs. Once completed, the lower basin will reduce this flow rate to 209 cfs, and provide improved flood protection for Brentwood and Oakley. SUPERVISOR DISTRICT:III AFFECTED AREA:Oakley, Brentwood PROGRAM TYPE:System Expansion PROJECT PRIORITY:3 FUNDING SOURCE(S):Drainage Area 130, possible future Federal, State and local grants, Flood Control Zone 1 TOTAL PROJECT COST:$7,414,500 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):YES NOTE: $20,000 $20,000 $61,000 $111,000 $882,000 $1,139,750 $5,180,750 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:222 Drainage Area 130 $20,000 $20,000 $61,000 $111,000 $882,000 $1,139,750 $5,180,750 November 2021 27 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Flood Control Zone 1 Facilities Condition Assessment WORK ORDER:8360 PROJECT DESCRIPTION:Hire specialized consultants to assess conditions of existing facilities. Two-phase approach: start with initial assessment, and proceed to more detailed assessment as warranted. PROJECT NEED:Need to identify deficiencies and conduct a retrofit plan, if needed. SUPERVISOR DISTRICT:III AFFECTED AREA:The Cities of Brentwood and Oakley PROGRAM TYPE:System Preservation PROJECT PRIORITY:1 FUNDING SOURCE(S):Flood Control Zone 1 TOTAL PROJECT COST:$510,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $200,000 $0 $0 $0 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:227 Flood Control Zone 1 $200,000 $0 $0 $0 $0 $0 $0 November 2021 28 / 29 CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Marsh Creek Reservoir Emergency Spillway Rehabilitation WORK ORDER:TBD PROJECT DESCRIPTION:Improve performance of spillway by adding erosion control messure at concrete apron PROJECT NEED:To avoid toe erosion upon use of spill way SUPERVISOR DISTRICT:III AFFECTED AREA:Brentwood PROGRAM TYPE:System Preservation PROJECT PRIORITY:2 FUNDING SOURCE(S):Flood Control Zone 1 TOTAL PROJECT COST:$280,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N): NOTE: $0 $0 $20,000 $260,000 $0 $0 $0 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:232 Flood Control Zone 1 $0 $0 $20,000 $260,000 $0 $0 $0 November 2021 29 / 29 Appendix B Unprogrammed Future Projects Details UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Wildcat / San Pablo Creeks Phase II WORK ORDER:WO TBD PROJECT DESCRIPTION:Channel improvements in Wildcat Creek and San Pablo Creek in the City of San Pablo upstream of BNSF railroad tracks PROJECT NEED:The previous Corps projects stopped at the BNSF railroad. Significant residual flood risk remains in the portions of San Pablo and Wildcat Creeks in the City of San Pablo upstream of the BNSF railroad. This project would consist of the coordination needed with the Corps for expansion of the system upstream. SUPERVISOR DISTRICT:I AFFECTED AREA:San Pablo PROGRAM TYPE:System Expansion PROJECT PRIORITY:5 FUNDING SOURCE(S):City of San Pablo, US Army Corps of Engineers TOTAL PROJECT COST:$13,250,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $0 $0 $0 $0 Future $13,250,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:9 Unfunded $0 $0 $0 $0 $0 $0 $0 $13,250,000 September 2021 1 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Pinole Creek Habitat Restoration (1135 Project) WORK ORDER:8493 PROJECT DESCRIPTION:Improve riparian habitat throughout the limits of the previous Army Corps of Engineers project. Remove possible fish barriers and improve habitat while preserving and expanding flood conveyance. Work within the USACE 1135 Program to ensure federal participation in this project. PROJECT NEED:The Pinole Creek USACE project is dated and single purpose. Center for Ecosystem Management and Restoration has identified Pinole Creek as primary steelhead habitat in the west Contra Costa County. Habitat improvements are needed to ensure migrating steelhead pass successfully through the project area to habitat upstream. SUPERVISOR DISTRICT:V AFFECTED AREA:Pinole PROGRAM TYPE:System Preservation PROJECT PRIORITY:5 FUNDING SOURCE(S):City of Pinole, USACE 1135 Program (75% - $5M limit) TOTAL PROJECT COST:$6,875,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $0 $0 $0 $0 Future $6,875,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:12 Unfunded $0 $0 $0 $0 $0 $0 $0 $6,875,000 September 2021 2 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Sustainable Capacity Improvement at Rodeo Creek WORK ORDER:WO TBD PROJECT DESCRIPTION:Rehabilitate or replace concrete-lined portion of creek to improve conveyance, restore habitat PROJECT NEED:Rodeo Creek is a 1960s era USACE channel, is devoid of most habitat, and is difficult to keep desilted, especially in the lowest reach. A new, more sustainable design of the creek is needed, and it has the potential to serve as a catalyst for further revitalization of the adjacent community. This project would also reduce long term dredging costs. SUPERVISOR DISTRICT:V AFFECTED AREA:Rodeo PROGRAM TYPE:System Preservation PROJECT PRIORITY:3 FUNDING SOURCE(S):Unfunded TOTAL PROJECT COST:$11,315,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $0 $0 $0 $0 Future $11,315,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:17 Unfunded $0 $0 $0 $0 $0 $0 $0 $11,315,000 September 2021 3 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Canada di Cierbo Habitat Improvement WORK ORDER:WO TBD PROJECT DESCRIPTION:Create a mitigation bank for County and District mitigation needs. Acquire right of way, develop restoration plan, implement plan and reap benefits. PROJECT NEED:Public projects often have unavoidable habitat impacts. Often, the remedy is to 'buy in' to a bank which is often located outside of the county. While this provides habitat mitigation, it does little to actually offset the impacts locally. The west part of CCC is underserved for this type of bank. Canada di Cierbo seeks to remedy this and provide quality, local mitigation and habitat improvement. SUPERVISOR DISTRICT:V AFFECTED AREA:Crockett, Unincorporated County PROGRAM TYPE:System Preservation PROJECT PRIORITY:5 FUNDING SOURCE(S):TBD TOTAL PROJECT COST:$3,500,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N): NOTE: $0 $0 $0 $0 $0 $0 $0 Future $3,500,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:23 Unfunded $0 $0 $0 $0 $0 $0 $0 $3,500,000 September 2021 4 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Pinole Creek Capacity Assessment WORK ORDER:TBD PROJECT DESCRIPTION:Assess creek capacity and watershed conditions and develop alternatives for improving flood protection in the area. PROJECT NEED:Watershed conditions have changed significantly with land development projects decreasing flood protection in the area. This project is intended to study watershed and creek conditions and develop alternatives for improving flood protection levels. SUPERVISOR DISTRICT:I AFFECTED AREA:Cities of Hercules and Pinole PROGRAM TYPE:System Preservation PROJECT PRIORITY:5 FUNDING SOURCE(S): TOTAL PROJECT COST:$350,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:Zone 9 (Pinole Creek) is significantly underfunded. Funding for this item is very uncertain. $0 $0 $0 $0 $0 $0 $0 Future $350,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:26 Unfunded $0 $0 $0 $0 $0 $0 $0 $350,000 September 2021 5 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:DA 67 - Tice Creek Bypass WORK ORDER:WO TBD PROJECT DESCRIPTION:Construct 66-inch bypass pipe in Tice Valley Boulevard, Meadow Road and Lancaster to provide a bypass for storm flows in Tice Creek PROJECT NEED:The 2004 completion of the Rossmoor Detention Basin significantly reduced flood risk for this area providing approximately a 20-year level of protection from Tice Creek. This long-planned bypass pipe would provide additional conveyance while allowing Tice Creek to remain in it's natural state. SUPERVISOR DISTRICT:II AFFECTED AREA:Walnut Creek, Unincorporated County PROGRAM TYPE:System Expansion PROJECT PRIORITY:5 FUNDING SOURCE(S):Grant funds, City of Walnut Creek funds, other funds TBD. TOTAL PROJECT COST:$2,730,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $0 $0 $0 $0 Future $2,730,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:117 Unfunded $0 $0 $0 $0 $0 $0 $0 $2,730,000 September 2021 6 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:DA 33A Concord Boulevard Culvert Replacement WORK ORDER:WO TBD PROJECT DESCRIPTION:Replace an undersized 60-inch culvert under Concord Blvd with a 117-inch by 79-inch arch culvert PROJECT NEED:The existing culvert is undersized and stormwater backs up and inundates Concord Blvd. The replacement culvert will be able to pass a 25-year storm event, lessening the risk of flooding on Concord Blvd. This is a cooperative project with the City of Concord. Per the 5-24-2005 JEPA, DA 33A will contribute a maximum of 90% of available funds which is currently approximately $209k. SUPERVISOR DISTRICT:IV AFFECTED AREA:Concord PROGRAM TYPE:System Expansion PROJECT PRIORITY:4 FUNDING SOURCE(S):Drainage Area 33A funds TOTAL PROJECT COST:$350,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $0 $0 $0 $0 Future $350,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:120 Drainage Area 33A $0 $0 $0 $0 $0 $0 $0 $200,000 Unfunded $0 $0 $0 $0 $0 $0 $0 $150,000 September 2021 7 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Pine Creek Reservoir Sediment Removal and Capacity Restoration WORK ORDER:WO TBD PROJECT DESCRIPTION:Remove accumulated sediment in Pine Creek Reservoir to restore design flood storage capacity. Create wetlands in new reservoir bottom as mitigation of impacts. Rehabilitate primary and emergency spillways to extend design life. PROJECT NEED:Another CIP project will first perform a functional assessment to verify continued need for reservoir. If found to still be needed, then this project will restore design functionality and extend the design life. SUPERVISOR DISTRICT:IV AFFECTED AREA:Walnut Creek, Unincorporated County PROGRAM TYPE:System Preservation PROJECT PRIORITY:4 FUNDING SOURCE(S):Flood Control Zone 3B TOTAL PROJECT COST:$5,500,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:Seismic evaluation is covered under a separate CIP entry because seismic work will likely be combined with other dams. $0 $0 $0 $0 $0 $0 $0 Future $5,500,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:124 Flood Control Zone 3B $0 $0 $0 $0 $0 $0 $0 $5,500,000 September 2021 8 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:San Ramon Creek Sediment Removal near San Ramon Bypass WORK ORDER:WO TBD PROJECT DESCRIPTION:Desilt San Ramon Creek downstream of the San Ramon Bypass diversion structure in Alamo to the bypass channel at the San Ramon PP Corridor PROJECT NEED:The San Ramon Creek Bypass Channel has a complex series of weirs allowing both low flows and high flows to continue down San Ramon Creek. Flows between those extremes are bypassed through the bypass system. The grades in San Ramon Creek downstream of the low flow pipe outfall prevent those low flows from passing into San Ramon Creek. This project would allow base flows to remain in the natural channel. SUPERVISOR DISTRICT:IV AFFECTED AREA:District IV PROGRAM TYPE:system Preservation PROJECT PRIORITY:4 FUNDING SOURCE(S):Flood Control Zone 3B TOTAL PROJECT COST:$400,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $0 $0 $0 $0 Future $400,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:125 Flood Control Zone 3B $0 $0 $0 $0 $0 $0 $0 $400,000 September 2021 9 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Green Valley Creek Improvements up to 1st Crossing of Diablo Road WORK ORDER:WO TBD PROJECT DESCRIPTION:Hire specialized consultants to assess conditions of existing facilities. Two-phase approach: start with initial assessment, and proceed to more detailed assessment as warranted. PROJECT NEED:The existing channel is incised and lacks the capacity to pass the 100-year flood event. The project is needed to lower the flood risk to the surrounding neighborhood. SUPERVISOR DISTRICT:II AFFECTED AREA:Danville PROGRAM TYPE:System Expansion PROJECT PRIORITY:4 FUNDING SOURCE(S):Flood Control Zone 3B TOTAL PROJECT COST:$7,300,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $0 $0 $0 $0 Future $7,300,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:128 Flood Control Zone 3B $0 $0 $0 $0 $0 $0 $0 $7,300,000 September 2021 10 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Green Valley Creek Improvements Upstream of 2nd Crossing of Diablo Road WORK ORDER:WO TBD PROJECT DESCRIPTION:Hire specialized consultants to assess conditions of existing facilities. Two-phase approach: start with initial assessment, and proceed to more detailed assessment as warranted. PROJECT NEED:Green Valley Creek at this location has erosion pressures and capacity issues. Past creek improvements stopped just downstream. This project will improve erosion and capacity conditions. SUPERVISOR DISTRICT:II AFFECTED AREA:Danville PROGRAM TYPE:System Preservation PROJECT PRIORITY:5 FUNDING SOURCE(S):Flood Control Zone 3B & Town of Danville TOTAL PROJECT COST:$2,300,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $0 $0 $0 $0 Future $2,300,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:129 Flood Control Zone 3B $0 $0 $0 $0 $0 $0 $0 $2,300,000 September 2021 11 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:DA 48B Line A at Port Chicago Highway WORK ORDER:WO TBD PROJECT DESCRIPTION:Design and Construct 595 LF of 84-inch storm drain crossing Port Chicago Highway near Skipper Drive. This is a portion of DA 48B, Line A. PROJECT NEED:The existing 60-inch pipe under Port Chicago Highway is undersized and in poor condition. Construction of the replacement 84-inch storm drain will extend the service life of the facility and reduce flood risk for the surrounding community. SUPERVISOR DISTRICT:V AFFECTED AREA:Bay Point PROGRAM TYPE:System Preservation PROJECT PRIORITY:5 FUNDING SOURCE(S):Contra Costa County Redevelopment, DA 48B TOTAL PROJECT COST:$490,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE: $0 $0 $0 $0 $0 $0 $0 Future $490,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:201 Drainage Area 48B $0 $0 $0 $0 $0 $0 $0 $490,000 September 2021 12 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:West Antioch Creek Improvements - L Street to 10th Street WORK ORDER:WO TBD PROJECT DESCRIPTION:Design and construct channel improvements from the downstream end of "L" Street Crossing to the upstream end of the 10th Street culverts in conjunction with the City of Antioch PROJECT NEED:The current channel was constructed only to an interim capacity and currently does not contain a 100-year storm event. Bottlenecks include the UPRR arch culvert and the narrow channel through the fairgrounds. This project will need to be constructed prior to constructing the third 10-foot pipe under Highway 4. SUPERVISOR DISTRICT:V AFFECTED AREA:Antioch PROGRAM TYPE:System Expansion PROJECT PRIORITY:5 FUNDING SOURCE(S):Drainage Area 55, City of Antioch, Grants, developer funds (upon development of the fairgrounds) TOTAL PROJECT COST:$5,466,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):NO NOTE:Project needs to proceed before CIP#204. $0 $0 $0 $0 $0 $0 $0 Future $5,466,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:203 Unfunded $0 $0 $0 $0 $0 $0 $0 $5,466,000 September 2021 13 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:West Antioch Creek Improvements at Highway 4 WORK ORDER:WO TBD PROJECT DESCRIPTION:Complete the storm drain system between "L" Street and Fitzuren Road. Work includes a new headwall downstream of "L" Street, one 8' by 10' box culvert under "L" Street, a single 10' diameter storm drain up to and under Highway 4 to connect to the exiting 10' pipes just north of Fitzuren Road. This results in a complete, triple 10' storm drain system. PROJECT NEED:Caltrans / CCTA has constructed a second bore under the highway as part of freeway widening in 2015. This CIP project completes the third bore between Fitzuren Road and "L" Street, and should not be constructed until downstream improvements (W. Antioch Creek at 10th Street, and W. Antioch Creek 10th Street to "L" Street) are constructed. See project #203. SUPERVISOR DISTRICT:III & V AFFECTED AREA:Antioch PROGRAM TYPE:System Expansion PROJECT PRIORITY:5 FUNDING SOURCE(S):Drainage Area 55, City of Antioch, Grants TOTAL PROJECT COST:$2,500,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):YES NOTE:Project should follow construction of project #203. $0 $0 $0 $0 $0 $0 $0 Future $2,500,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:204 Unfunded $0 $0 $0 $0 $0 $0 $0 $2,500,000 September 2021 14 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:Fitzuren Road Remainder Parcel WORK ORDER:WO TBD PROJECT DESCRIPTION:Prepare conceptual plans and facilitate development of three District-owned parcels on Fitzuren Road. Market these parcels for a commercial use, such as a restaurant or neighborhood retail. PROJECT NEED:These parcels were purchased in the 1980s to allow the construction of three large storm drains to carry West Antioch Creek. They were purchased with the intent of developing the unused portion once the storm drains were installed. The storm drain was designed to maximize the unused portion of the parcels and thus maximize the revenue generating potential for the District and DA 55. This project will follow the construction of the final 10' storm drain through the parcel. SUPERVISOR DISTRICT:III AFFECTED AREA:Antioch PROGRAM TYPE:System Expansion PROJECT PRIORITY:5 FUNDING SOURCE(S):Drainage Area 55, Flood Control District TOTAL PROJECT COST:$255,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):YES NOTE:Project should follow construction of project #204. $0 $0 $0 $0 $0 $0 $0 Future $255,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:205 Drainage Area 55 $0 $0 $0 $0 $0 $0 $0 $255,000 September 2021 15 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:East Antioch Creek Marsh Restoration WORK ORDER:WO TBD PROJECT DESCRIPTION:Design and construct marsh and floodplain improvements on East Antioch Creek downstream of Cavallo Road. Includes marina outlet channel (or equivalent), hazardous material clean-up on affected portion of Hickmont site, and three new box culverts under Wilbur Avenue. PROJECT NEED:Provide flood protection in the lower watershed of East Antioch Creek in accordance with the adopted Drainage Area 56 (DA 56) plan SUPERVISOR DISTRICT:V AFFECTED AREA:Antioch PROGRAM TYPE:System Expansion PROJECT PRIORITY:5 FUNDING SOURCE(S):Drainage Area 56 TOTAL PROJECT COST:$11,370,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):Yes NOTE: $0 $0 $0 $0 $0 $0 $0 Future $11,370,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:206 Unfunded $0 $0 $0 $0 $0 $0 $0 $11,370,000 September 2021 16 / 17 UNPROGRAMMED FUTURE CAPITAL IMPROVEMENT PROJECT SUMMARY REPORT PROJECT NAME:DA 109 - Kellogg Creek Project Development WORK ORDER:TBD PROJECT DESCRIPTION:Re-analyze the Kellogg Creek (Drainage Area 109) Plan and develop projects for future implementation PROJECT NEED:The current DA 109 plan is conceptual, and while sufficient to collect funds for improvements, the plan lacks the detail to develop and prioritize projects in the watershed. This effort will re-study the DA 109 plan to define specific projects for implementation, rank those projects, and then begin implementation in priority order. SUPERVISOR DISTRICT:III AFFECTED AREA:Town of Discovery Bay PROGRAM TYPE:System Expansion PROJECT PRIORITY:5 FUNDING SOURCE(S):DA 109 Funds TOTAL PROJECT COST:$300,000 EAST COUNTY HABITAT CONSERVATION PLAN (Y/N):YES NOTE: $0 $0 $0 $0 $0 $0 $0 Future $300,000 PLANNED PROJECT EXPENDITURES AND FUNDING SOURCE(S) PROJECT EXPENDITURES: FUNDING SOURCE(S): FY 21/22 FY 22/23 FY 23/24 FY 24/25 FY 25/26 FY 26/27 FY 27/28 ID:225 Drainage Area 109 $0 $0 $0 $0 $0 $0 $0 $300,000 September 2021 17 / 17 TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE 10. Meeting Date:11/08/2021   Subject:CONSIDER report: Local, Regional, State, and Federal Transportation Issues: Legislation, Studies, Miscellaneous Updates, take ACTION as Appropriate Submitted For: TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE,  Department:Conservation & Development Referral No.: 1   Referral Name: REVIEW legislative matters on transportation, water, and infrastructure.  Presenter: John Cunningham, DCD Contact: John Cunningham (925)655-2915 Referral History: This is a standing item on the Transportation, Water, and Infrastructure Committee referral list and meeting agenda. Referral Update: In developing transportation related issues and proposals to bring forward for consideration by TWIC, staff receives input from the Board of Supervisors (BOS), references the County's adopted Legislative Platforms, coordinates with our legislative advocates, partner agencies and organizations, and consults with the Committee itself. This report includes four sections, 1: LOCAL, 2: REGIONAL, 3: STATE, and 4: FEDERAL . 1. LOCAL Accessible Transportation Strategic (ATS) Plan Update One of the primary recommendations of the ATS Plan (Approved in 2021) was to convene a Task Force to guide the implementation of the plan. The first meeting of the Task Force was held on October 21st, the following is a summary of actions and discussion from that meeting:  Membership Staff discussed the currently empty seat for the low-income community and solicited feedback from the Task Force. Debbie Toth (Choice in Aging) proposed adding another seat to include Mobility Matters who is active in the accessible transportation field in Contra Costa Funding  Measure X: Staff described the Measure X funding source and process to the Task Force. The ATS Plan scored relatively high in the rankings. The Board of Supervisors will take the issue up at their November 16th meeting. If the ATS Plan is approved it is anticipated that funding would be available in Spring 2022. Transportation Network Company (TNC) Access for All (SB 1376): Some funding is available through this recently passed legislation which is meant to address the inaccessibility of the TNC fleet (Lyft, Uber). It is a new program, the amount, availability, and reliability of the funding is still relatively unknown.  Blue Ribbon Transit Recovery Task Force Staff described the intersection between the ATS Plan and this Metropolitan Transportation Commission (MTC) led effort that was initiated in 2020. While the Blue Ribbon effort was initiated with a focus on fixed route transit and safety, it did include recommendations specific to accessible transportation. Those recommendations are similar to the goals of the ATSP, MTC may be looking to Contra Costa as a model for implementation. Next Steps The TF discussed future agenda items which include a presentation on the one-seat ride pilot program, a review of different organizational models and funding mechanisms. The TF also discussed the need to form subcommittees focused on these and other specific ATSP recommendations. 2. REGIONAL No regional report in November. 3. STATE Update The County's legislative advocate will be in attendance at the November meeting. The Committees list of tracked bills is attached.  Proposed Accessible Transportation Legislation from the California Senior Legislature As reported at the October Committee meeting, the California Senior Legislature (CSL) is proposing new legislation to fund and improve accessible transportation statewide. County staff and our legislative advocate have been providing support to the CSL on the topic given the supporting language in our State Legislative Platform (see below). The proposal would create the Accessible Transportation Account (ATA), authorize Consolidated Transportation Services Agencies (CTSAs, authorized under existing law) to oversee expenditures at the local level, and improve the CTSA mechanism. While vehicle registration/license fees are cited as potential revenue sources in the proposal, that specific detail has not yet been finalized.  The origin of the bill was the State's Master Plan for Aging (MPA) process which began in 2019 and was completed in early 2021. The MPA addressed a spectrum of aging issues including housing, caregiving, affordability of aging, fighting isolation, and transportation. The transportation recommendations in the final MPA was an outlier relative to the other topics, the input of the Stakeholder Advisory Committee were disregarded and replaced by non-substantive talking points without explanation or consultation with the Stakeholders. The State's response to the Stakeholder transportation input was unusual not only in its disparate treatment relative to the other topic areas, but also given that the recommendations were relatively modest, strengthening existing statutes and promoting widely accepted best practices. The speculation among staff is that it was the Stakeholders insistence that the State actually fund and implement the recommendations so they don't "sit on a shelf" caused the recommendations to be rejected and rewritten. The frustration with the State's response combined with a legacy of inaction drove several members of the CSL to propose legislation to address the transportation issue. The MPA effort is just the latest transportation recommendations in the aging space to be disregarded by the State, reports in 2005 and 2007 were ignored as well.  Update: The CSL held their annual legislative session in October, from the 26th to the 28th, the legislative proposal was approved.  The proposal is consistent with our adopted State Legislative Platform as follows: The proposal is consistent with our adopted State Legislative Platform as follows: Legislative and/or Regulatory Advocacy Priorities: Transportation for Seniors, Persons with Disabilities Climate Change: SUPPORT efforts to expand eligible expenditures of the Climate Investments to investments in accessible transit/transportation systems (serving seniors, disabled, and veterans) which result in more efficient service and corresponding reductions in greenhouse gas production, and in investments in infrastructure and programs to promote active transportation, particularly bicycling and walking. Human Services: Older Adults: • SUPPORT continued and improved funding to expand services for older adults and people with disabilities. 4. FEDERAL No federal report in November. Recommendation(s)/Next Step(s): CONSIDER report on Local, Regional, State, and Federal Transportation Related Legislative Issues and take ACTION as appropriate. Fiscal Impact (if any): There is no fiscal impact. Attachments 2021 Tracked Legislation TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE 11. Meeting Date:11/08/2021   Subject:REVIEW Communication, News, Miscellaneous Items of Interest to the Committee and DIRECT staff as appropriate. Submitted For: TRANSPORTATION, WATER & INFRASTRUCTURE COMMITTEE,  Department:Conservation & Development Referral No.: N/A   Referral Name: N/A  Presenter: John Cunningham, DCD Contact: John Cunningham (925)674-7833 Referral History: This is a standing item on the TWIC agenda. Referral Update: Communication Received: 10/16/2021 Email From Leland Frayseth (County resident) re: Las Vaqueros Reservoir 275,000 acre-feet - CCWD Board to flounder in Closed Session 10/20/2021 Email from Leland Frayseth (County resident) re: Re: Las Vaqueros Reservoir 275,000 acre-feet - CCWD Board to flounder in Closed Session Recommendation(s)/Next Step(s): RECEIVE information and DIRECT staff as appropriate. Fiscal Impact (if any): N/A Attachments Leland Frayseth 10-16-2021 Email Leland Frayseth 10-20-2021 Email 1 John Cunningham From:Leland Frayseth <leland.frayseth@gmail.com> Sent:Saturday, October 16, 2021 6:10 PM To:Samantha.Arthur@cwc.ca.gov; Alexandre.Makler@cwc.ca.gov; daniel.curtin@cwc.ca.gov; Teresa.Alvarado@cwc.ca.gov; Matthew.Swanson@cwc.ca.gov; Kimberly.Gallagher@cwc.ca.gov; Fern.Steiner@cwc.ca.gov; Jose.Solorio@cwc.ca.gov; cwc@water.ca.gov; Shoemaker, Brianna@DWR; amy.young@water.ca.gov; Cambra, Paul@CWC; Yun, Joseph@DWR; Klopfenstein, Rachael@DeltaCouncil; erik.erreca@deltacouncil.ca.gov; John Cunningham; spalmer@zone7water.com; Bob Wright; Obegi, Doug; Daniel Bacher; Scott Anderson; Rachel Murphy; Kennedy, Kellye J; Jennifer Allen Subject:Las Vaqueros Reservoir 275,000 acre-feet - CCWD Board to flounder in Closed Session Attachments:10.20.21 Special Board Meeting Agenda.pdf; 41_1019.003_Los_Vaqueros_Dam_InspRpt_20181031 _redacted.pdf.pdf Subject:  Las Vaqueros Reservoir 275,000 acre‐feet ‐ CCWD Board to flounder in Closed Session    Dear Commissioners, Staff and the Public,    This is my 42nd letter to the California Water Commission please add this comment to the 20 Oct 2021 meeting agenda  item 9 Water Storage Investment Program: Los Vaqueros Reservoir Expansion Project Continuing Eligibility and  Feasibility Determination (Action Item).  I am a 37 year Contra Costa Water District (CCWD) ratepayer of Los Vaqueros  Reservoir 100,000 and 160,000 acre‐feet that gives me poor water quality, has a longitudinal crack in its crest and never  was filled to 160,000 acre‐feet after being raised in 2012.    I think this item should be pulled from the agenda. There is no way Staff could have determined Los Vaqueros is  feasible or "will advance the long‐term objectives of restoring ecological health and improving water management for  beneficial uses of the Delta."      Every major reservoir in the West is almost empty; there are millions of acre‐feet unused surface storage capacity in the  Colorado and Sacramento River Basins.  There is no water to fill them because you changed the climate by burning fossil  fuels to pump water to the Central Valley and up the Tehachapi Mountains.  That dumped tons of Carbon into the  atmosphere.  Last Spring I told you to embrace the Next California Project to move Central Valley farming the Mississippi  Delta where there is abundant water.    You will dump tons more Carbon into the atmosphere burning diesel fuel for construction and earthmoving equipment  to tear down the 160,000 acre‐feet dam built in 2012 further exacerbating climate change.    I think Lisa Borba and her CCWD Board know the fish are winning in Court that is why they have to meet in Closed  session.  There will be water for fish but no 275,000 acre‐feet reservoir.  My tap water has been particularly nasty this  year while they try to drain that stagnant pool through my kitchen faucet and shower head.    The 275,000 acre‐feet schedule has slipped 5 years since what was on their Prop 1 application. CCWD's Board approved  a plan to buy water from East Bay Municipal District (EBMUD) during the 5 year construction.  EBMUD has no water to  spare Comanche Reservoir and the Mokelumne River are dangerously low pulse flows for salmon are a trickle of what  they should be from the California Data Exchange Format queries I pull.    The Federal Infrastructure Bill has not passed and its prospects look grim, there will be no more federal money for Los  Vaqueros 275,000 acre‐feet.    2 Please Commissioners if this item does not get pulled from the agenda and you do vote on it, vote it down.  I know these  people at CCWD very well, I have been their customer for 37 years. The 275,000 acre‐feet Los Vaqueros project should  be canceled, the project team terminated and migrating salmon should get the water.    Leland Frayseth    CONTRA COSTA WATER DISTRICT SPECIAL MEETING AGENDA Wednesday, October 20, 2021 at 6:00 p.m. 1331 Concord Avenue, Concord – Board Room (in-person) or Via Teleconference (617) 829-7560 CLICK ITEM NUMBER TO VIEW REPORT Pursuant to the authorizations provided in CCWD Resolution 21-017, this meeting may be conducted telephonically or by other electronic means. One or more Directors may attend via electronic means. If participating telephonically, please call into the teleconference up to 10 minutes before the scheduled start time. The Telephonic Meeting Participation Guide is the final page of this Agenda [or click here.] Members of the public may speak on any matter within the jurisdiction of the Contra Costa Water District: in person by filling out a speaker’s card available at the Board Room entrance and giving it to the District Secretary; during the teleconference when comments are requested; or in writing/email sent to and received by the District Secretary by 4:30 p.m. on the meeting day to be read into the record (up to 3 minutes in length). Comments on matters not listed on the agenda will be taken during the “Public Comment” section of the agenda. Comments on matters listed on the agenda will be taken during consideration of that agenda item. The District Secretary may be contacted at (925) 688-8024; vsepulveda@ccwater.com; or 1331 Concord Avenue, Concord, CA 94520. Agendas, agenda-packet materials, and other supporting documents are available at: ccwater.com, 1331 Concord Avenue in Concord, or by calling the District Secretary. A fee may be charged for copies. District facilities and meetings comply with the Americans with Disabilities Act. If special accommodations are needed for you to participate, please contact the District Secretary as soon as possible, but preferably at least two days prior to the meeting. Food will be available for staff and Board members during the hour before the Board meeting. If Board members are present, they will not discuss District business. CALL TO ORDER SAFETY BRIEFING ROLL CALL ADOPTION OF AGENDA PUBLIC COMMENT (Please observe a three-minute time limit) This section of the agenda is provided so that the public may express comments on any item within the District’s jurisdiction not listed on the agenda. Board members can ask questions for clarification, respond to statements or questions from members of the public, refer a matter to staff, or follow Board procedures to direct staff to place a matter of business on a future agenda. The public may express comments on agenda items at the time of Board consideration, per Board President instructions. Special Board of Directors Agenda October 20, 2021 Page 2 CLOSED SESSION 1. Conference with Legal Counsel – Existing litigation pursuant to paragraph (1) of subdivision (d) of Section 54956.9: (PCFFA v. U.S. Department of Commerce, Case No. 1:20-cv-00426-DAD-EPG and California Natural Resources Agency v. U.S. Department of Commerce, Case No. 1:20-cv-00431-DAD- EPG; United States District Court, Eastern District). RECONVENE FROM CLOSED SESSION 2. Report on closed session. ADJOURNMENT The next meeting of the Board of Directors will be a regular meeting on Wednesday, October 20, 2021 commencing at 6:30 p.m. in the Board Room located at 1331 Concord Avenue in Concord and also available via teleconference. Special Board of Directors Agenda October 20, 2021 Page 3 Teleconference Participation Guide • Please call (617) 829-7560 to join the Board meeting, up to 10 minutes before the meeting start time of 6:00 p.m. o You will hear an informational recording welcoming you to the meeting o Disregard the request to announce yourself when you join the conference call o You will hear music while on hold until the meeting begins o Please do not place the call on hold o Place your phone on mute when you are not speaking to reduce background noise o Please call back by dialing the same number if you get disconnected o During the call you may hear several different teleconference announcements o There will be needed pauses during the meeting to allow for teleconference facilitation and participation • During the meeting, you may hear an announcement: “Muted.” This is to prevent unintended background noises, such as dogs barking, sirens, etc., from disrupting the meeting. 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Your comments are appreciated. 1 John Cunningham From:Leland Frayseth <leland.frayseth@gmail.com> Sent:Wednesday, October 20, 2021 8:22 AM To:Samantha.Arthur@cwc.ca.gov; Alexandre.Makler@cwc.ca.gov; daniel.curtin@cwc.ca.gov; Teresa.Alvarado@cwc.ca.gov; Matthew.Swanson@cwc.ca.gov; Kimberly.Gallagher@cwc.ca.gov; Fern.Steiner@cwc.ca.gov; Jose.Solorio@cwc.ca.gov; cwc@water.ca.gov; Shoemaker, Brianna@DWR; amy.young@water.ca.gov; Cambra, Paul@CWC; Yun, Joseph@DWR; Klopfenstein, Rachael@DeltaCouncil; erik.erreca@deltacouncil.ca.gov; John Cunningham; spalmer@zone7water.com; Bob Wright; Obegi, Doug; Daniel Bacher; Scott Anderson; Rachel Murphy; Kennedy, Kellye J; Jennifer Allen Subject:Re: Las Vaqueros Reservoir 275,000 acre-feet - CCWD Board to flounder in Closed Session Attachments:04 - LVRE 275 TAF Project Facilities.pdf; 02.03.21-4 Backstop MOU with EBMUD.pdf Dear Commissioners, Staff and the Public,    I see item 9 is still on the agenda for your meeting this morning so as you vote I want you to have the attached latest Los  Vaqueros schedule and Backstop MOU.  Lisa Borba has not coordinated or gotten sign off from incidental take fish in the  draining Los Vaqueros and Comanche reservoirs, migrating Sacramento and Mokelumne river salmon, steelhead,  fisherwomen and fishermen, EBMUD and CCWD customers who will be impacted by the schedule, Backstop MOU and  reservoir refill.    I have a lot of Department of Water Resources (DWR) public records requests to type in and queue up this morning so I  will miss your meeting but I will watch the recorded video when you publish it.    Leland  2   3     On Sat, Oct 16, 2021 at 6:09 PM Leland Frayseth <leland.frayseth@gmail.com> wrote:  Subject:  Las Vaqueros Reservoir 275,000 acre‐feet ‐ CCWD Board to flounder in Closed Session    Dear Commissioners, Staff and the Public,    4 This is my 42nd letter to the California Water Commission please add this comment to the 20 Oct 2021 meeting agenda  item 9 Water Storage Investment Program: Los Vaqueros Reservoir Expansion Project Continuing Eligibility and  Feasibility Determination (Action Item).  I am a 37 year Contra Costa Water District (CCWD) ratepayer of Los Vaqueros  Reservoir 100,000 and 160,000 acre‐feet that gives me poor water quality, has a longitudinal crack in its crest and  never was filled to 160,000 acre‐feet after being raised in 2012.    I think this item should be pulled from the agenda. There is no way Staff could have determined Los Vaqueros is  feasible or "will advance the long‐term objectives of restoring ecological health and improving water management for  beneficial uses of the Delta."      Every major reservoir in the West is almost empty; there are millions of acre‐feet unused surface storage capacity in  the Colorado and Sacramento River Basins.  There is no water to fill them because you changed the climate by burning  fossil fuels to pump water to the Central Valley and up the Tehachapi Mountains.  That dumped tons of Carbon into the  atmosphere.  Last Spring I told you to embrace the Next California Project to move Central Valley farming the  Mississippi Delta where there is abundant water.    You will dump tons more Carbon into the atmosphere burning diesel fuel for construction and earthmoving equipment  to tear down the 160,000 acre‐feet dam built in 2012 further exacerbating climate change.    I think Lisa Borba and her CCWD Board know the fish are winning in Court that is why they have to meet in Closed  session.  There will be water for fish but no 275,000 acre‐feet reservoir.  My tap water has been particularly nasty this  year while they try to drain that stagnant pool through my kitchen faucet and shower head.    The 275,000 acre‐feet schedule has slipped 5 years since what was on their Prop 1 application. CCWD's Board approved  a plan to buy water from East Bay Municipal District (EBMUD) during the 5 year construction.  EBMUD has no water to  spare Comanche Reservoir and the Mokelumne River are dangerously low pulse flows for salmon are a trickle of what  they should be from the California Data Exchange Format queries I pull.    The Federal Infrastructure Bill has not passed and its prospects look grim, there will be no more federal money for Los  Vaqueros 275,000 acre‐feet.    Please Commissioners if this item does not get pulled from the agenda and you do vote on it, vote it down.  I know  these people at CCWD very well, I have been their customer for 37 years. The 275,000 acre‐feet Los Vaqueros project  should be canceled, the project team terminated and migrating salmon should get the water.    Leland Frayseth    Agenda Item No. 4 Meeting Date: February 3, 2021 Resolution: No AGENDA DOCKET FORM SUBJECT: MEMORANDUM OF UNDERSTANDING WITH EAST BAY MUNICIPAL UTILITY DISTRICT FOR DEVELOPMENT OF BACKSTOP WATER SERVICE DURING LOS VAQUEROS RESERVOIR EXPANSION PROJECT CONSTRUCTION SUMMARY: Implementation of the Los Vaqueros Reservoir Expansion Project (Project) includes increasing the existing reservoir capacity from 160,000 acre-feet up to 275,000 acre-feet. In order to facilitate construction of modifications to the dam and associated facilities, the Los Vaqueros Reservoir will need to be drawn down completely for up to three years. The Contra Costa Water District (District) is evaluating options for securing supplemental water conveyance and/or water supplies during the reservoir outage period to ensure there are no water quality or water supply impacts to the District’s customers as a result of Project construction. One of the most feasible options for supplemental water conveyance is through use of the existing untreated water intertie with East Bay Municipal Utility District (EBMUD). This intertie connects the District’s Los Vaqueros Pipeline to EBMUD’s Mokelumne Aqueduct No. 2 and has a capacity of 155 cubic feet per second. The intertie has been successfully operated to convey water to the District’s Transfer Facility and to the Contra Costa Canal. (Continued on Page 2) FISCAL IMPACT: The current FY21-22 Project budget includes adequate funding for District staff and consultant support for implementation of the MOU. EBMUD is currently providing in-kind services for the Project through the existing Multi-Party Funding Agreement. EBMUD will ultimately seek reimbursement for the costs it incurs to provide Backstop Water Service. It is anticipated that EBMUD’s costs would be reimbursed by the future Los Vaqueros Reservoir Joint Powers Authority (JPA) and the terms for provision of Backstop Water Service and reimbursement would be included in a future Backstop Water Service Agreement. RECOMMENDED ACTION: Authorize execution of the Memorandum of Understanding between the East Bay Municipal Utility District and the Contra Costa Water District for development of Backstop Water Service during Los Vaqueros Reservoir Expansion Project construction. _________________________ Maureen Martin Special Projects Manager _________________________ Marguerite Patil Assistant General Manager _________________________ Stephen J. Welch General Manager MP/MM:wec Attachments: 1) Summary of MOU Principles, 2) Presentation Slides MOU with EBMUD February 3, 2021 Page 2 AGENDA DOCKET FORM SUMMARY (Continued from Page 1): The District and EBMUD have executed several existing agreements that provide for various uses of the untreated water intertie, including: 1) for the delivery of water to either agency through the intertie in the event of an emergency; 2) for diversion of up to 3,200 acre-feet per year of the District’s Central Valley Project (CVP) water at EBMUD’s Freeport Intake on the Sacramento River and conveyance through EBMUD’s system and delivery to the District through the intertie; and 3) for long-term operation and maintenance of the intertie that provides for the sharing of water resources in emergencies or to support planned critical work. The District and EBMUD have developed a new memorandum of understanding (MOU) that establishes the collaborative, good faith effort the agencies will undertake to develop a new agreement to allow for expanded use of the intertie during Project construction. The MOU describes the guiding principles and key actions needed to allow the District to divert its Central Valley Project contract supplies or Los Vaqueros water right water supplies at EBMUD’s Freeport Intake and convey those supplies to the District through the untreated water intertie. The water conveyance and water supply services requested from EBMUD are referred to as “Backstop Water Service”. The Backstop Water Service sought in the MOU is in addition to operations that are allowed under existing agreements between the District and EBMUD. Under most hydrologic conditions, the District would not require Backstop Water Service as the water quality at the District’s Delta intakes would be sufficient to meet water quality delivery goals. The Backstop Water Service would most likely be called upon in two circumstances : 1) during a drought when salinity at the District’s intakes does not meet the District’s salinity goals and fresher water is needed to blend with supplies diverted at the District’s intakes , and 2) to hasten the re- filling of the reservoir following Project construction. In the event of an emergency, other than a drought, EBMUD would provide water according to the terms of other existing agreements. A summary of the key principles included in the MOU are included in Attachment 1. If the results of the analysis described in the MOU confirm that EBMUD can reliably provide Backstop Water Service, the District and EBMUD will develop a final Backstop Water Service Agreement which sets forth mutually acceptable terms and conditions for the provision of Backstop Water Service. If the results of the analysis indicate that EBMUD cannot reliably provide Backstop Water Service, the District would consider other options for supplemental water conveyance and/or water supplies during Project construction. The analysis is anticipated to be completed by Fall 2021. Attachment 1 Summary of MOU Principles 1)The Parties will work together in good faith to analyze EBMUD’s ability to provide Backstop Water Service to CCWD during Project construction and subsequent refill of Los Vaqueros. The Parties will cooperate to identify and analyze issues relevant to the potential provision of such services to CCWD by EBMUD. 2)Parties have agreed to evaluate the following conditions under which Backstop Water Service may be necessary: a.Non-Drought/Non-Emergency Conditions: This scenario is intended to capture CCWD’s potential needs to meet CCWD’s delivered water quality goals, normally provided by Los Vaqueros, under non-emergency conditions during non-drought years. For this purpose, “non-drought years” means hydrologic year types EBMUD would not typically require use of Freeport Regional Water Project nor request voluntary or mandatory water use reductions from its customers. b.Drought/Non-Emergency Conditions: This scenario is intended to capture CCWD’s potential needs to meet CCWD’s delivered water quality goals, normally provided by Los Vaqueros, under non-emergency conditions during drought years. For this purpose, “drought years” means hydrologic year types EBMUD would typically require use of Freeport Regional Water Project and/or request voluntary or mandatory water use restrictions from EBMUD’s customers. c.Refill of Los Vaqueros Reservoir: This scenario is intended to capture the potential to refill Los Vaqueros after construction is completed using Freeport Regional Water Project during “non-drought years” as defined above. 3)Emergency condition scenarios are not expected to be analyzed as part of this work because CCWD’s rights to use EBMUD’s facilities in emergency conditions are defined by existing agreements. 4)The source of supply for Backstop Water Service would be CCWD’s CVP contract or the Los Vaqueros water right. 5)Consistent with the 2016 Principles of Agreement Regarding Wheeling of Water for CCWD through EBMUD Facilities, EBMUD will work together with CCWD on any water rights change(s) necessary for CCWD to divert water appropriated under its CVP Contract and Los Vaqueros water right (Permit No. 20749) at the Freeport Regional Water Project. 6)If EBMUD and CCWD each determine that Backstop Water Service can be provided, the Parties, in coordination with the Los Vaqueros Reservoir Joint Powers Authority as may be necessary, will negotiate in good faith a final written Backstop Water Service Agreement which sets forth mutually acceptable terms and conditions for the provision of Backstop Water Service. 7)The Parties agree that EBMUD shall be entitled to reimbursement for the costs it incurs to provide Backstop Water Service to CCWD, and such right to reimbursement shall be assured in any final Backstop Water Service Agreement. 8)EBMUD will continue to provide documentation of labor and services expended to CCWD to document its in-kind services provided to the Project as described in the Multi-party Agreement. AGENDA ITEM NO. 4 BACKSTOP MOU WITH EBMUD BOARD OF DIRECTORS MEETING FEBRUARY 3, 2021 Attachment 2 BACKSTOP MOU WITH EBMUD Background •CCWD and the East Bay Municipal Utility District (EBMUD) have an existing untreated water intertie •Connects Los Vaqueros Pipeline & Mokelumne Aqueduct No. 2 •Capacity is 155 cubic feet per second (cfs) •Intertie operates in both directions FEBRUARY 3, 2021 BOARD OF DIRECTORS MEETING AGENDA ITEM NO. 4 2 EBMUD-CCWD Intertie 350 cfs capacity 250 cfs capacity 250 cfs capacity 155 cfs capacity 39 cfs capacity 160 TAF capacity Transfer Pipeline 200 cfs fill 400 cfs release capacity Old River Pipeline 320 cfs capacity BACKSTOP MOU WITH EBMUD Background •2002 -EBMUD and CCWD entered into an agreement for the delivery of water to either agency in the event of an emergency •2004 -EBMUD and CCWD entered into an agreement for wheeling up to 3,200 acre-feet per year of CCWD’s Central Valley Project (“CVP”) water through the Freeport Regional Water Project (FRWP) •2007 -EBMUD and CCWD entered into an agreement for long- term operation and maintenance of the untreated water intertie that provides for the sharing of water resources in emergencies or to support planned critical work FEBRUARY 3, 2021 BOARD OF DIRECTORS MEETING AGENDA ITEM NO. 4 3 BACKSTOP MOU WITH EBMUD Background •2011, 2013, & 2014 -EBMUD wheeled water through the raw water intertie for delivery to CCWD •2016 -EBMUD and CCWD adopted Principles of Agreement Regarding Wheeling of Water for CCWD through EBMUD Facilities that expressed the parties’ commitment to: •work together to develop an agreement for additional use of the intertie for mutual benefit •seek permits needed to divert CCWD’s Los Vaqueros water right water at FRWP •explore the possibility of using the Los Vaqueros Reservoir to store water for EBMUD FEBRUARY 3, 2021 BOARD OF DIRECTORS MEETING AGENDA ITEM NO. 4 4 BACKSTOP MOU WITH EBMUD Construction of Los Vaqueros Dam Raise •To construct dam raise, the site adjacent to the dam foundation will need to be dry, and the reservoir will need to be drained •During dam construction, the District would not have access to the water quality and emergency supplies normally provided by Los Vaqueros Reservoir •District is seeking Backstop Water Service during this period to ensure no water quality or water supply impacts to District customers FEBRUARY 3, 2021 BOARD OF DIRECTORS MEETING AGENDA ITEM NO. 4 5 BACKSTOP MOU WITH EBMUD Backstop Water Service •The District is seeking a backup source of high-quality water •Could be needed during construction of the dam raise if the Delta is too salty to meet District’s water quality delivery goals •This situation would typically occur during a drought and/or during re-fill of the reservoir •Provisions for conveyance and/or supplies during droughts and during re-fill of the reservoir are not covered in existing agreements with EBMUD FEBRUARY 3, 2021 BOARD OF DIRECTORS MEETING AGENDA ITEM NO. 4 6 BACKSTOP MOU WITH EBMUD FEBRUARY 3, 2021 BOARD OF DIRECTORS MEETING AGENDA ITEM NO. 4 7 Water quality blending during droughts Wheeling of 3.2 TAF/year of CCWD CVP Water Planned Critical Work and Non- Drought Emergencies Existing Intertie O&M Agreement Existing Freeport Agreement New LVE Backstop Agreement BACKSTOP MOU WITH EBMUD Emergency Supplies •Emergency condition scenarios are not expected to be analyzed as part of this work because that is covered by existing agreements •The source of supply for Backstop Water Service would be the District’s Central Valley Project (CVP) contract or Los Vaqueros water right FEBRUARY 3, 2021 BOARD OF DIRECTORS MEETING AGENDA ITEM NO. 4 8 BACKSTOP MOU WITH EBMUD Next Steps •EBMUD and CCWD conduct analyses to determine that Backstop Water Service can be provided under the desired conditions •A final Backstop Water Service Agreement will be drafted which sets forth mutually acceptable terms and conditions for the provision of Backstop Water Service •EBMUD will be entitled to reimbursement (funded by JPA) for the costs it incurs to provide Backstop Water Service to CCWD FEBRUARY 3, 2021 BOARD OF DIRECTORS MEETING AGENDA ITEM NO. 4 9 BACKSTOP MOU WITH EBMUD Next Steps (cont.) •EBMUD will work together with CCWD on any water rights change(s) necessary for CCWD to divert water appropriated under its CVP Contract and Los Vaqueros water right at Freeport FEBRUARY 3, 2021 BOARD OF DIRECTORS MEETING AGENDA ITEM NO. 4 10 4 CONTRA COSTA WATER DISTRICT Staff Report DATE: September 8, 2021 TO: Operations and Engineering Committee FROM: Stephen J. Welch SUBJECT: Los Vaqueros Reservoir Expansion Project – Facilities Update INTRODUCTION The Contra Costa Water District (District) continues to conduct planning, permitting, cost estimating, and design of Phase 2 Los Vaqueros (LV) Reservoir Expansion Project (LVE Project) facilities, consistent with the Multi-Party Agreement with the Local Agency Partners (LAPs), the Funding Agreement with the California Water Commission (CWC) and the proposed Assistance Agreement with the United States Bureau of Reclamation (Reclamation) approved by the Board on June 16, 2021. The purpose of this report is to provide an overview of the new facilities and upgrades at the Transfer Facility and to provide an update on the LV Dam Expansion design schedule. RECOMMENDATION Receive report and comment. DISCUSSION The LVE Project includes the design and construction of several new conveyance facilities, modifications to existing conveyance facilities and expansion of the LV Dam (see Exhibit A). The District continues to progress a variety of facilities planning, design and cost estimating to support the project and to refine the planned timeline (see Exhibit B). The focus of this report is to provide an update on the planned Expanded Transfer Facility and the Transfer Pump Station upgrades, which will be the hub of all water deliveries for the LVE Project. This report also provides an update on the schedule for California Division of Safety of Dams (DSOD) approval of the application for the expanded reservoir. Existing Transfer Facility The existing Transfer Facility, constructed as part of the original LV Project, consists of: 1) Transfer Pump Station, a 200 cubic-feet per second (cfs) pump station to fill the LV Reservoir, and 2) Transfer Reservoir, a four million gallon (MG) steel tank. The Transfer Facility is the conveyance hub that directs diversions from Old River Pump Station and Middle River Pump Station to fill and Operations and Engineering Committee LVE Project - Facilities Update September 8, 2021 Page 2 release water from the LV Reservoir, delivers water to the Contra Costa Canal (Canal), and for water deliveries for the East Bay Municipal Utilities District intertie. Transfer Reservoir provides operational storage and is the hydraulic control to prevent over-pressurizing the LV Pipeline. Expanded Transfer Facility The LVE Project will construct new facilities within the existing Transfer Facility site to deliver water to the Transfer-Bethany Pipeline for conveyance to the California Aqueduct and the LAPs. The Expanded Transfer Facility includes a new Transfer-Bethany Pump Station, a new flow control station (Flow Control Station No. 3), and a new 10 MG Transfer Reservoir No. 2. The new pump station will have a design capacity of 300 cfs, consisting of seven 50 cfs pumps designed to meet maximum pumping demands with one of the pumps out of service for routine maintenance or an unplanned outage. The new pump station will convey water to the Transfer-Bethany Pipeline that is either diverted from Old River, Middle River or pumped from the Canal through the proposed Neroly High Lift Pump Station. Water released from the Expanded LV Reservoir will flow through Flow Control Station No. 3 by gravity to the Transfer-Bethany Pipeline for delivery to the California Aqueduct. The new flow control station will be similar to the two existing flow control stations designed and constructed with the original LV Project to control releases from the LV Reservoir and deliveries to the Canal. The new Transfer Reservoir No. 2 will be constructed adjacent to the existing Transfer Reservoir and will operate in parallel to balance flows during LVE operations. The District completed operational modeling and determined the new reservoir should be 10 MG to provide sufficient operational storage for the variety of LVE operations while protecting against potential overflow or reservoir-draining events. Modeling evaluated use of multiple intakes and pump stations at maximum anticipated capacities, time needed for operational decisions in reaction to events, systematic adjustments to changing demands, and emergency shutdowns. Transfer Pump Station Upgrades The existing 200 cfs Transfer Pump Station, consisting of four 50-cfs pumps, will be upgraded to deliver water to the elevated water surface of the expanded LV Reservoir. Upgrades will be designed to meet planned LVE operations and provide operational flexibility to meet changing conditions and water supply demands. The existing pumps will be replaced with pumps capable of delivering 200 cfs to the expanded reservoir with one pump out of service. Variable frequency drives are also planned to enable pumping through the full range of reservoir levels while matching the combined flows from the other pump stations. Matching flows will simplify operations and provide flexibility as adjustments are made to other facility operations. Los Vaqueros Dam Expansion Design Final design of the expanded LV Dam is needed to secure approval from the DSOD, prior to the CWC award of the full funding agreement. The timing of the CWC award has been extended to Operations and Engineering Committee LVE Project - Facilities Update September 8, 2021 Page 3 allow the LAPs to complete formation of the LV Reservoir Joint Powers Authority and to enter into the other agreements that are also needed prior to full funding, anticipated in Summer 2022 at the earliest. DSOD has reviewed progressive design submittals and participated in meetings with the District’s Technical Review Board. The 90-percent dam expansion design plans and specifications were submitted in June. DSOD recently notified the District that the lead project engineer has been promoted to a position working on other projects and that DSOD is in the process of hiring a replacement, which will result in a delay as the new engineer is on-boarded. Working with DSOD, the District has revised the design review schedule to align with DSOD’s resources and meet the anticipated CWC approval timeframe. The following is an updated summary of the key dam review and approval milestones:  DSOD Comments on 90-percent Dam Design November 2021  Submit 100-percent Dam Design February 2022  DSOD Approval of Dam Expansion May 2022 FISCAL IMPACT Staff, consulting services and agency fees are funded by existing agreements with the CWC and LAPs. The District has proposed Amendment No. 3 to the Multi-Party Agreement with the LAPs to fund activities in 2022 and is working with Reclamation to finalize the Assistance Agreement to provide matching funds for costs incurred from January 1, 2021 through December 20, 2022. The Fiscal Year 2022 budget includes sufficient funds to cover anticipated expenditures. The District continues to monitor work progress to ensure the consultant work does not exceed the funds available. SW/RM/CH:mc Exhibits: A – LVE Project Facilities B – LVE Project Schedule C – Presentation Slides Exhibit A LVE Project Facilities Exhibit B LVE Project Schedule AGENDA ITEM NO. 4 LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE OPERATIONS AND ENGINEERING COMMITTEE SEPTEMBER 8, 2021 Exhibit C LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE AGENDA ITEM NO. 4 Project Facility Activities •Detailed design of several facilities is progressing to meet the LVE Project schedule •Pumping Plant No. 1 Replacement •Transfer-Bethany Pipeline •Los Vaqueros (LV) Dam Expansion •Plans for new and upgraded facilities continue to be evaluated to confirm the LVE Project scope and cost SEPTEMBER 8, 2021 OPERATIONS AND ENGINEERING COMMITTEE 2 LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE AGENDA ITEM NO. 4 LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE AGENDA ITEM NO. 4 Existing Transfer Facility •Hub of the LV system operation for diversions and deliveries to storage and the Canal •Transfer Pump Station can deliver up to 200 cubic feet per second (cfs) to the existing LV Reservoir •4 million gallon (MG) reservoir provides operational storage and hydraulic control SEPTEMBER 8, 2021 OPERATIONS AND ENGINEERING COMMITTEE 4 LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE AGENDA ITEM NO. 4 Expanded Transfer Facility •New facilities located within the existing Transfer Facility •Transfer-Bethany Pump Station •Transfer Reservoir No. 2 •Flow Control Station No. 3 SEPTEMBER 8, 2021 OPERATIONS AND ENGINEERING COMMITTEE Flow Control Station No. 3 Transfer-Bethany PS 5 LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE AGENDA ITEM NO. 4 Transfer-Bethany Pump Station •Deliver 300 cfs through the Transfer-Bethany Pipeline to the CA Aqueduct •Meet design capacity with one pump out of service •Include Variable Frequency Drives to efficiently match flows and simplify operations •New electrical feed, substation and electrical building SEPTEMBER 8, 2021 OPERATIONS AND ENGINEERING COMMITTEE 6 LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE AGENDA ITEM NO. 4 Transfer Reservoir No. 2 •10 MG reservoir will operate in parallel with existing Transfer Reservoir •Provides operational storage and hydraulic control to balance operations •Sized to prevent overflow or draining under normal and emergency operating conditions SEPTEMBER 8, 2021 OPERATIONS AND ENGINEERING COMMITTEE 7 LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE AGENDA ITEM NO. 4 Flow Control Station No. 3 •Controls LV releases to Transfer-Bethany Pipeline for conveyance to CA Aqueduct •Dual sleeve valve provides redundancy, matching existing District flow control stations •Design to minimize surge potential, applying lessons from original LV Project SEPTEMBER 8, 2021 OPERATIONS AND ENGINEERING COMMITTEE 8 LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE AGENDA ITEM NO. 4 Transfer Pump Station Upgrades •Replace pumps, motors and electrical equipment •Deliver 200 cubic-feet per second to the highest reservoir level SEPTEMBER 8, 2021 OPERATIONS AND ENGINEERING COMMITTEE 9 •Meet design capacity with one pump out of service •Install variable frequency drives to efficiently match other LVE operations •Install additional surge protection LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE AGENDA ITEM NO. 4 Los Vaqueros Dam Expansion •Complete design and obtain Division of Safety of Dams (DSOD) approval prior to full funding agreement •DSOD staffing changes have slowed review of 90 percent design •Final design planned for February 2022 •DSOD Approval anticipated in May 2022 •Revised schedule meets LVE Project objectives SEPTEMBER 8, 2021 OPERATIONS AND ENGINEERING COMMITTEE 10 LOS VAQUEROS RESERVOIR EXPANSION PROJECT –FACILITIES UPDATE AGENDA ITEM NO. 4 Fiscal Impact •Funding for ongoing work is included in project agreements: •Multi-Party Agreement Amendment No. 3 •CWC Early Funding Agreement •Pre -Construction Agreement with Reclamation SEPTEMBER 8, 2021 OPERATIONS AND ENGINEERING COMMITTEE 11