HomeMy WebLinkAboutMINUTES - 06272000 - C5 TO: BOARD OF SUPERVISORS ''"'
FROM: MAURICE M. SHIU, PUBLIC WORKS DIRECTOR
DATE: JUNE 27, 2000
SUBJECT: APPROVE THE CHRISTIE ROAD SLIDE REPAIR PROJECT AND ADOPT THE CEQA
NEGATIVE DECLARATION, HERCULES AREA. PROJECT NO. 0672-6R6351-98.
CDD-CP#00-37.
Specific Request(s) or Recommendation(s) & Background & Justification
I, RECOMMENDED ACTION:
APPROVE the Christie Road Slide Repair Project, and
FIND, on the basis of the initial study and all comments received, that there is no substantial
evidence that the project will have a significant effect on the environment, and
ADOPT the Negative Declaration in compliance with the California Environmental Quality Act
(the custodian of which is the Public Works Director who is located at 255 Glacier Drive,
Martinez), and
DIRECT the Director of Community Development to file a Notice of Determination with the
County Clerk, and
Continued an Attachment: X SIGNATURE". U1 ,
RECOMMENDATION OF COUNTY ADMINISTRATOR
RECOMMENDATION OF BOARD COMMITTEE
—APPROVE —OTHER
SIGNATURES :
ACTION OF BOARD ON JUNE 27, 2000 APPROVED AS RECOMMENDED OTHER
VOTE OF SUPERVISORS
_X_ UNANIMOUS(ABSENT NONE I hereby certify that this is a true and correct
AYES: NOES: — copy of an action taken and entered on the
LC:df ABSENT: ABSTAIN:--__ minutes of the Board of Supervisors on the
G:1GrpData\EngSvc\ENVIRO\2000projects\CEQAoniy\BoardOrdersl date shown.
BOChristieRoadSlide
Orig.Div: Public works(Engineering Services Division)
Contact: K. Emigh, Design JUNE 27, 2000
cc: County Administrator ATTESTED:
Attn: E. Kuevor PHIL BATCHELOR, Clerk of the Board of
Auditor-Controller Supervisors and Count Administrator
Community Development--S.Casillas p y
PW Accounting
Construction
L.Chavez, Eng. Services By
Deputy
SUBJECT: APPROVE THE CHRISTIE ROAD SLIDE REPAIR PROJECT AND ADOPT THE CEQA
NEGATIVE DECLARATION, HERCULES AREA, PROJECT NO. 0672-6R6351-98,
CDD CP# 00-37:
DATE: JUNE 27, 2000
FACE: 2
1. Recommgnded Action (continued):
AUTHORIZE the Public Works Director to arrange for payment of a $25 fee to Community
Development for processing, and a $25 fee to the County Clerk for filing the Notice of
Determination, and
DIRECT the Public Works Director to arrange for the $1,250 Fish and Game filing fee to be
transferred to the County Clerk.
li. FINANCIAL IMPACT:
The estimated cost of the project is $400,000. The project will be 60% FEMA funded, 20%
State Office of Emergency Services funded, and 20% Local Road Funds funded.
1111E REASONS FOR RECOMMEN DATIONIBACKGROUND:
The project will address three areas of bank instability between Christie Road and Rodeo
Creek. The first two areas will be addressed by relocating the roadway away from the slide
areas and the third area will be repaired by constructing a retaining wall between the road and
Rodeo Creek.
The project is needed to stabilize the failing banks and roadway.
The project has been determined to be in compliance with the General Plan. A Negative
Declaration of environmental significance pertaining to this project was published on 5/9/00.
The Board has considered the Negative Declaration together with all comments received
during the public review period.
IV. CQNSS QUENCES OF NEGATIVE ACTION:
Delay in approving the project will result in a delay of design and construction and may
jeopardize funding.
CONTRA PUBLIC WORKS DEPARTMENT
COSTA INITIAL STUDY
COUNTY OF ENVIRONMENTAL SIGNIFICANCE
PROJECT#11+672-6R6351-88
CP#00-37
PROJECT NAME: Christie Road Slide Repair Project
PREPARED BY: Leigh Ch DATE: 5/4/00
APPROVED BY: DATE. to)
RECOMMENDATIONS:
() Categorical Exemption (Class) (X) Negative Declaration
() Environmental Impact Report Required () Conditional Negative Declaration
The project will not have a significant effect on the environment. The recommendation is
based on the following; There Is no substantial evidence that the project or any of its aspects
may cause a significant effect on the environment{Sec. 15063(b)(2)).
What changes to the project would mitigate the Identified Impacts N/A
USGS Quad Sheet Briones Valley Base Map Sheet# Gg, G10 Parcel# N/A
GENERAL CONSIDERATIONS:
1. Location: The Christie Road slide areas are located along Christie Road above Rodeo
Creek In central Contra Costa County. Christie Road Is the only access to several homes
(Figures 1-4).
2. Project Description:
Christie Road Is located above the northeastern bank of Rodeo Creek. The project will address
three areas of bank Instability between Christie Road and Rodeo Creek. The first two areas will
not be repaired. Instead, sine there is available area, the road will be relocated eastward toward
the B1uriington Northern Santa Fe (BNSF) Railroad tacks and away from the sloughing bank. The
road relocation will extend approximately 1100 feet and will require minor roadway excavation, the
placement of base rock,the placement of asphalt concrete, extension of a cross culvert, and minor
shoulder grading.
The third slide area is an imminent threat to Christie Road and there is no suitable area to relocate
the road away from the sloughing bank (the railroad is closer to the creek in this location). To
prevent further erosion of the roadway Into the creek, the slide will be repaired by constructing a
retaining wall longitudinally along Christie Road between the road and Rodeo Creek.The retaining
wall will be located parallel to Christie Road in a flat benched area created by the sloughing
material. The benched area is located approximately 20 feet below road grade. The retaining wall
will be approximately 9 feet high and will be located approximately 35 feet from the edge of the
road and 15 feet from the top of bank of Rodeo Creek. The wall will be approximately 295 feet long
and the piles for the wall will be approximately ?3 feet deep. Earthen fill will be
Christie Road Slide Repair Project-Initlai Study 7
Project No.17672-6116351-98,CP -37
Page 2 of 3
placed behind the retaining structure at a 2.1 slope up to road level.
Two petroleum pipelines run roughly perpendicular to the proposed retaining wall. One of these
pipelines runs approximately 10 feet below the road and has been abandoned and capped. The
second pipeline Is active and runs approximately 23 feet under the project roughly in the middle
of the proposed retaining wall. The retaining wall will be installed such that the plies of the wall
straddle the gas line. The owner of the pipeline will be notified of the proposed project and
schedule, and a representative from the company will be on-site during all construction activities
occurring near the pipeline.
As a result of coordination with the Northwest Information Center at Sonoma State University, the
County will retain a qualified archaeologist to monitor any excavated material as it is stockpiled on
the road. In addition,the County will Incorporate the requirement into the contract specification that
fill Imported for use behind the retaining wall will either be obtained from a known clean borrow site
or alternative borrow sites will be researched to ensure that no cultural resources will be impacted.
Results of soil and water sampling conducted at the project site indicate that groundwater that
could be encountered during construction, or collected by a subdrain system installed as a
component of the retaining wall project, may contain detectable levels of TEHd (diesel fuel). The
diesel fuel is suspected to be the result of the nearby petroleum pipelines. If groundwater is
encountered during construction It will either be treated prior to release into the creek or off-hauled
to a qualified treatment and/or storage facility.
Rather than installing a subdrain system behind the retaining wall that could potentially collect and
concentrate water containing detectable levels of TEHd, the County will install heavy gauge filter
fabric behind the retaining wall. The fabric will retain soil particles in place as groundwater
continues to flow through the soil. Based on this design (groundwater flow through the soil and
retaining wall similar to existing conditions, rather than collection and concentration of groundwater
In a subdrain system),the existing hydrology at the project site will not change significantly due to
the project. As a result,TEHd contamination levels entering Rodeo Creek will not be significantly
impacted by the project. The County will forward the results of the soil and water sampling to the
owners of the nearby pipelines and the owner of the property (the railroad).
Construction activities associated with the retaining wall and road relocation will impact the
minimum amount of riparian vegetation necessary; however, some tree and shrub removal will be
necessary (approximately 8 trees may require removal). All trees that require removal will be
replaced at a 3:1 ratio with like species up to one-gallon In size. The replacement trees will be
planted within the backfilled area above the retaining wall and will be maintained for a period of
three years and monitored for a period of five years.
California red-legged frog are known to occur near the project site. The Federal Emergency
Management Agency (FEMA) has consulted with the U.S. Fish and Wildlife Service (USFWS)
regarding red-legged frog at the project site. Based on the consultation, the project has been
determined to be Not Likely To Adversely Affect(NLTAA)the continued existence of the red-legged
frog. This determination has associated avoidance and minimization measures that must be
implemented in order to be valid. The measures include. Installation of silt fencing or other
sediment barriers to prevent soil from entering the creek; properly maintaining heavy equipment
to ensure that oils and other fluids do not leak and enter the creek; conducting work between July
1 and November 1; retaining a biologist to survey the project site and adjacent areas within 48
hours prior to the start of construction; and notifying USFWS If frogs are found during the pre-
construction survey. Although the County(through FEMA)has obtained the NLTAA determination
Christie Road Slide Repair Project-lnitlal Study
Prot No.0872-686351-98,CP 0-37
Page 3of3
from USFWS, in order to avoid potential construction delays associated with identifying frogs on
the project site, the County will obtain an lncldertbl take penriit from the USFWS to allow any
identified frogs to be legally relocated from the project site.
The project is located within the California Department of Fish and Game's (CDFG)jurisdiction.
Public Works Department staff will coordinate with staff from CDFG to obtain a Streambed
Alteration Agreement prior to implementation of the project. The County will comply with all the
conditions negotiated for the permit. The project is not within the U.S. Army Corps of Engineers
jurisdiction. As a result,Water Quality Certification from the Regional Water Quality Control Board
is not required; however, the County will apply for a Waiver of Waste Discharge Requirements
under the Porter-Cologne Water Quality Control Act from the Regional Board.
The existing road is the only access to several homes beyond the project site;therefore, access
beyond the project site must be maintained at all times to ensure that residents and emergency
services are not isolated by the project. At least one lane of Christie Road and/or additional
area Immediately adjacent to Christie Road will be open at all times for through traffic. Since.
Christie Road is located=within the Burlington Northern Santa Fe Railroad right of way, if
required by the railroad, the County will obtain a right of entry from the railroad in order to
conduct the repair work associated with the retaining wall and road relocation.
3, Does It appear that any feature of the project will generate significant public
concern? []yes M no [] maybe (Nature of concern):
4. Will the project require approval or permits by otherthan a County agency? (X] yes
a no Agency Name(s) California Department of Fish and Game (Streambed Alteration
Agreement), California Regional Water Quality Control Board (Porter-Cologne Waiver of
Waste Dlscharge Requirements), U.S. Fish and Wildlife Service (Section 7 Consultation),
Federal Emergency Management Agency(NEPA Categorical Exclusion).
5. Is the project within the Sphere of Influence of any city? No
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Environmental Checklist Form
1. Project Title: Christie Road Slide Repair Project
2. Lead Agency Name and Address: Contra Costa County Community .Development
Department
651 Pine Street,North Wing-4th Floor
Martinez, CA 94553
3. Contact Person and Phone Number: Leigh Chavez(925) 313-2366
4. Project Location: The subject site is located along Christie Road above
Rodeo Creek in central Contra Costa County. The
road is the only access to several homes.
5. Project Sponsor's Name/Address: Contra Costa County Public Works Department
6. General Plan Designation: Public and Semi-Public(Christie Road is located within
the Burlington Northern Santa Fe Railroad Right of
Way)
7. Zoning: Local Road
8. Description of Project:
Christie Road is located above the northeastern bank of Rodeo Creek. The project will address three
areas of bank instability between Christie Road and Rodeo Creek. The first two areas will not be
repaired. Instead, since there is available area, the road will be relocated eastward toward the
Burlington Northern Santa Fe Railroad tracks and away from the sloughing bank. The road
relocation will extend approximately 1100 feet and will require minor roadway excavation, the
placement of base rock, the placement of asphalt concrete, extension of a cross culvert, and minor
shoulder grading.
The third slide area is an imminent threat to Christie Road and there is no suitable area to relocate
the road away from the sloughing bank (the railroad is closer to the creek in this location). To
prevent further erosion of the roadway into the creek, the slide will be repaired by constructing a
retaining wall longitudinally along Christie Road between the road and Rodeo Creek. The retaining
wall will be located parallel to Christie Road in a flat benched area created by the sloughing material.
The benched area is located approximately 20 feet below road grade. The retaining wall will be
approximately 9 feet high and will be located approximately 35 feet from the edge of the road and
15 feet from the top of bank of Rodeo Creek. The wall will be approximately 295 feet long and the
piles for the wall will be approximately 23 feet deep. Earthen fill will be placed behind the retaining
structure at a 2:1 slope up to road level.
Two petroleum pipelines run roughly perpendicular to the proposed retaining wall. One of these
pipelines runs approximately 10 feet below the road and has been abandoned and capped. The
second pipeline is active and runs approximately 23 feet under the project roughly in the middle of
the proposed retaining wall. The retaining wall will be installed such that the piles of the wall
straddle the gas line. The owner of the pipeline will be notified of the proposed project and
schedule, and a representative from the company will be on-site during all construction activities
occurring near the pipeline.
As a result of coordination with the Northwest Information Center at Sonoma State University,the
County will retain a qualified archaeologist to monitor any excavated material as it is stockpiled on
the road. In addition,the County will incorporate the requirement into the contract specification that
fill imparted for use behind the retaining wall will either be obtained from a known clean borrow
site or alternative borrow sites will be researched to ensure that no cultural resources will be
impacted.
Results of soil and water sampling,conducted at the project site indicate that groundwater that could
be encountered during construction,or collected by a subdrain system installed as a component of
the retaining wall project, may contain detectable levels of TEHd(diesel fuel). The diesel fuel is
suspected to be the result of the nearby petroleum pipelines. If groundwater is encountered during
construction it will either be treated prior to release into the creek or off-hauled to an appropriate
treatment and/or storage facility.
Rather than installing a subdrain system behind the retaining wall that could potentially collect and
concentrate water containing detectable levels of TEHd,the County will install heavy gauge filter
fabric behind the retaining wall. The fabric will retain soil particles in place as groundwater
continues to flow through the soil. Based on this design(groundwater flow through the soil and
retaining wall similar to existing conditions,rather than collection and concentration of groundwater
in a subdrain system),the existing hydrology at the project site will not change significantly due to
the project. As a result,TEHd contamination levels entering Rodeo Creek will not be significantly
impacted by the project. The County will forward the results of the soil and water sampling to the
owner of the pipeline and the owner of the property(the railroad).
Construction activities associated with the retaining wall and road relocation will impact the
minimum amount of riparian vegetation necessary;however, some tree and shrub removal will be
necessary (approximately 8 trees may require removal). All trees that require removal will be
replaced at a 3:1 ratio with like species up to one-gallon in size. The replacement trees will be
planted within the backfilled area above the retaining wall and will be maintained for a period of
three years and monitored for a period of five years.
California red-legged frog are known to occur near the project site. The Federal Emergency
Management Agency (FEMA) has consulted with the U.S. Fish and Wildlife Service (USFWS)
regarding red-legged frog at the project site. Based on the consultation, the project has been
determined to be Not Likely To Adversely Affect (NLTAA) the continued existence of the red-
legged frog. This determination has associated avoidance and minimization measures that must be
implemented in order to be valid. The measures include; installation of silt fencing or other
sediment barriers to prevent soil from entering the creek;properly maintaining heavy equipment to
ensure that oils and other fluids do not leak and enter the creek;conducting work between July 1 and
November 1;retaining a biologist to survey the project site and adjacent areas within 48 hours prior
to the start of construction; and notifying USFWS if frogs are found during the pre-construction
survey. Although the County (through FEMA) has obtained the NLTAA determination from
USFWS, in order to avoid potential construction delays associated with identifying frogs on the
project site, the County will obtain an incidental take permit from the USFWS to allow any
identified frogs to be legally relocated from the project site.
The project is located within the California Department of Fish and Game's(CDFG)jurisdiction.
Public Works Department staff will coordinate with staff from CDFG to obtain a Streambed
Alteration Agreement prior to implementation of the project. The County will comply with all the
conditions negotiated for the permit. The project is not within the U.S. Army Corps of Engineers
jurisdiction. As a result,Water Quality Certification from the Regional Water Quality Control Board
is not required; however, the County will apply for a Waiver of Waste :Discharge Requirements
under the Porter-Cologne Water Quality Control Act from the Regional Board.
The existing road is the only access to several homes beyond the project site; therefore,access
beyond the project site must be maintained at all times to ensure that residents and emergency
services are not isolated by the project. At least one lane of Christie Road and/or additional area
immediately adjacent to Christie Road will be open at all times for through traffic. Since Christie
Road is located within the Burlington Northern Santa Fe Railroad right of way, if required by the
railroad,the County will obtain a right of entry from the railroad in order to conduct the repair
work associated with the retaining wall and road relocation.
9. Surrounding Land Uses and Setting: Land surrounding the project area consists of
undeveloped and agricultural uses.
10. Other public agencies whose approval is required (e.g., permits, financing approval, or
participation agreement): Regional Water Quality Control Board Porter-Cologne Waiver of
Waste Discharge Requirements, California Department of Fish and Game (Streambed
Alteration Agreement),U.S.Fish and Wildlife Service(Section 7 Consultation)
ENVIRONMENTAL FACTORS POTENTIALLY AFFECTED:
The environmental factors checked below would be potentially affected by this project, involving
at least one impact that is a "Potentially Significant Impact" as indicated by the checklist on the
following pages.
Land Use and _ Transportation/ Public Services
Planning Circulation — Utilities & Service
Population&Housing — Biological Resources Systems
Geological Problems Energy & Mineral i Aesthetics
_ Water Resources — Cultural Resources
_ Air Quality ,_,.,. Hazards — Recreation
Mandatory Findings of — Noise No Significant
Significance Impacts Identified
4
DETERMINATION
On the basis of this initial evaluation:
✓ I find that the proposed project COULD NOT have a significant effect on the environment,
and a NEGATIVE DECLARATION will be prepared.
I find that although the proposed project could have a significant effect on the environment,
there will not be a significant effect in this case because the mitigation measures described
on an attached sheet have been added to the project. A MITIGATED NEGATIVE
DECLARATION will be prepared.
_.. I find that the proposed project MAY have a significant effect on the environment, and an
ENVIRONMENTAL IMPACT REPORT is required.
I find that the proposed.project MAY have a significant effect(s)on the environment,but at
least one effect (I) has been adequately analyzed in an earlier document pursuant to
applicable legal standards,and(2)has been addressed by mitigation measures based on the
earlier analysis as described on attached sheets, if the effect is a "potentially significant
impact"' or "potentially significant unless mitigated." An ENVIRONMENTAL IMPACT
REPORT is required,but it must analyze only the effects that remain to be addressed.
I find that although the proposed project could have a significant effect on the environment,
there WILL NOT be a significant effect in this case because all potentially significant effects
(a)have been analyzed adequately in an earlier EIR pursuant to applicable standards and(b)
have been avo" ed or mitigated pursuant to that earlier EIR,including revisions or mitigation
m s imposea upon the proposed project. /t d
I It 11A
^igture Date
QQQ QLnvmw&EMsLgprxaent Dennaauirnent
Printed Name For
5
SOURCES
In the process of preparing the Checklist and conducting the evaluation, the following references
(which are available for review at the Mantra Costa County Community Development Department,
651 Pine Street 5th Floor-North Wing,Martinez)were consulted:
I. Contra Costa Resource Mapping System-Quad Sheet Panels for$riones valley and Benicia
Quadrangles,CA
2.. The(Reconsolidated)County General Plan(July 1996) and Draft EIR on the General Plan
(September 1990)
3. Contra Costa County Important Farmland Map 1998,California Department of Conservation
Division of hand Resources Protection, 1999
4. Field reviews and/or Project Description(including coordination with Design Engineer)
5. Soil Survey of Contra Costa.County, Soil Conservation Service,9/77
6. Contra Costa County Flood Insurance Rate Zone Information Map
7. State of California Hazardous Waste and Substances Sites List,April 1998
8. Geotechnical Investigation on Christie Road Slide Repair,T'errasearch,Inc. 1/17/00
9. Sail and Groundwater Analysis, Subsurface Consultants,Inc.,3/23/00
10. Leigh Jordan,Northwest Information Center,California State University Sonoma,Pers,com.
2/18/00)
11. Edward Wylie,U.S.Army Corps of Engineers,pers. com. 3/31/99
12. FEMA Listed Species Consultation documentation(2/1/00)
EVALUATION OF ENVIRONMENTAL IMPACTS:
Potentially
Significant
Potentially Unless Leas than
significant Mitigation significant No
lit Iatsmmfion It>lt
I. AESTHMCS. Would the proposal:
a. Have a substantial adverse effect on a _
scenic vista?(Source#1,2,4)
b. Substantially damage scenic resources,
including,but not limited to,trees,rock
outcroppings,and historic buildings within
a state scenic highway?(Source##1,2,4)
C. Substantially degrade the existing _ _
visual character or quality of the site and
its surroundings?(Source#1,2,4)
d. Create a new source of substantial light X
or glare which would adversely affect
day or nighttime views in the area?
Source#4)
6
SUMMARY: The retaining wall will be located parallel to Christie Road in a flat benched area
created by the sloughing material. The benched area is located approximately 20 feet below road
grade. The retaining wall will be approximately 9 feet high and will be located approximately 35
feet from the edge of the road. The wall will be approximately 295 feet long. Earthen fill will be
placed behind the retaining structure at a 2:1 slope up to road level. The wall itself will be
difficult to see from Christie Road since the top of the wall will be approximately 10 feet below
road grade.
Construction activities associated with the retaining wall will impact the minimum amount of
vegetation necessary to complete the retaining wall. There are approximately three trees located
in the slide area that will require removal to facilitate construction of the retaining wall. These
trees include a bay tree(approximately 6"dbh)and two willow trees(approximately 2"dbh). In
addition,along Christie Road at the edges of the proposed retaining wall, several trees border the
slide. Approximately five of these trees(3 —5"dbh coast live oak trees)may require removal in
order to construct an access road into the slide area and to tie the wall back into the areas
adjacent to Christie Road. Every effort will be made to retain as many trees in place as feasible.
All trees that are removed as a result of the construction activity will be replaced at a 3:1 ratio in
the backfilled area above the retaining wall. A representative from the County will be onsite
during tree removal to determine the actual number of trees removed for replacement purposes.
In order to minimize a damage to any additional trees that will not require removal,but may be
impacted by construction, contract specifications will include protective measures such as clean
trimming of roots and limbs. Removal of the trees will not have a substantial adverse effect on
scenic resources. The three trees in the slide zone appear to have been displaced by the slide
activity. The bay tree is the most visible of the three trees in the slide area. Due to the
displacement,the base of the tree is approximately 10 feet below the road;therefore,the tree is
not highly visible from the road. The bay tree,in particular,is leaning relatively severely and
may not survive if left in place,based on the displacement. The additional five trees that are
located along Christie Road that may require removal as a result of construction of the access
roads,are surrounded by many additional trees; therefore,removal of these trees will not
significantly alter the visual quality of the project area.
The visual quality of the road realignment areas will not change significantly as a result of the
project. The area is dominated by annual grasses and coyote brush(Baccharis sp.). Removal of
these grasses and shrubs will not significantly impact the aesthetics of the project site. All
exposed areas will be seeded with a mix including native grasses and wildflowers following
completion of the project.
Construction equipment will be visible temporarily during construction of the retaining wall and
relocation of the roadway,however this is a minor and short-term impact,ending upon
completion of the project. Building the retaining structure and relocated road will not create a
permanent source of significant new light or glare.
7
Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
t iltion Im2a lm2aut
II. AGRICULTURAL RESOURCES: In determining
whether impacts to agricultural resources are
significant environmental effects,lead agencies
may refer to the California Agricultural Land
Evaluation and Site Assessment Model(1997)
prepared by the California Dept.Of Conservation
as an optional model to use in assessing impacts
on agricultural and farmland. Would the project:
a.' Convert Prime Farmland,Unique Farmland,
or Farmland of Statewide Importance
(Farmland),as shown on the maps prepared
pursuant to the Farmhand Mapping and Monitoring
Program of the California Resources Agency,
to non-agricultural use?(Source#1,3)
b. Conflict with existing zoning for X
agricultural use,or a Williamson
Act contract?(Source#1,2)
C. Involve other changes in the existing
environment which,due to their location
or nature,could result in conversion of
Farmland,to nonagricultural use?(source#1,2,3,4)
The project will not impact any locally or statewide important farmland. The land
immediately adjacent to the project consists of undeveloped and agricultural land. The Contra.Costa
County Important Farmland Map (1998) identifies the project as being within"grazing land". in
addition, the County Resource Mapping System identifies a number of agricultural preserves
surrounding the project area. However, the area where the wall will be installed consists of very
steep slopes that are not suitable for grazing, and the areas where the mad will be relocated are
positioned between the steep slopes above Rodeo Creek and the Burlington Northern Santa Fe
Railroad trach,therefore,no grazing occurs in the area. No agricultural preserves are located in the
immediate vicinity of the project.
III. AIR QUALITY. Where available,the
significance criteria established by the
applicable air quality management or air
pollution control district may be relied upon
to make the following determinations.
Would the project:
a. Conflict with or obstruct implementation _
of the applicable air quality plan?
(Source#2,4)
8 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
jmnact Incorporation Im ac Imact
b. Violate any air quality standard or X —
contribute to an existing or projected
air quality violation?(Source#2,4)
C. Result in a cumulatively considerable _ _ X
net increase of any criteria pollutant for
which the project region is non-attainment
under an applicable federal or state ambient
air quality standard(including releasing
emissions which exceed quantitative
thresholds for ozone precursors)?
(Source#2,4)
d. Expose sensitive receptors to substantial o X
pollutant concentrations?(Source#2,4)
e. Create objectionable odors affecting a _ X v
substantial number of people?
(Source#2,4)
S LtY: Short-term emissions and objectionable odors may be generated during
construction; however,they will be minor and temporary. In order to minimize impacts due to
construction activities,contract specifications will stipulate the use of properly tuned and
muffled equipment and the elimination of unnecessary idling of equipment when not in use.
Implementation of dust control practices including general watering of exposed areas and/or use
of chemical stabilizers will also minimize air quality impacts. The minor temporary
deterioration of ambient air quality at the construction site will have no potentially adverse long-
term impacts to air quality. No permanent air quality impacts due to vehicle traffic will be
generated by the project since no additional trips will be generated by the installation of the
retaining wall and relocation of the roadway. Installation of the retaining wall and relocation of
the roadway will not increase the capacity of Christie Road.
IV. BIOLOGICAL RESOURCES. Would the project:
a. have a substantial adverse effect, either _ X
directly or through habitat modifications,
on any species identified as a candidate,
sensitive, or special status species in local
or regional plans,polices,or regulations, or
by the California Department of Fish and
Game or U.S.Fish and Wildlife Service?
(Source#1,2,4,12)
b. Have a substantial adverse effect on any _ X _.
riparian habitat or other sensitive natural
community identified in local or regional
plans,policies,regulations or by the California
9 Potentially
Significant
Potentially Unless Loss than
Significant Mitigation Significant No
1t Incomgration 1M2V1 1nm=
Department of Fish and Game or US Fish
and Wildlife Service?(Source#1,2,4)
C. Have a substantial adverse effect on
federally protected wetlands as defined
by Section 404 of the Clean Water Act
(including,but not limited to,marsh,vernal
pool,coastal,etc.)through direct removal,
filling,hydrological interruption,or other
means?(Source#1,2,4)
d., Interfere substantially with the movement _ X
of any native resident or migratory fish or
wildlife species or with established native
resident or migratory wildlife corridors,or
impede the use of native wildlife nursery sites?
Source#1,2,4,12)
e. Conflict with any local policies or
ordinances protecting biological resources,
such as tree preservation policy or ordinance?
Source#2)
f Conflict with the provisions of an _
adopted Habitat Conservation Plan,
Natural Community Conservation Plan,
or other approved local,regional,or
state habitat conservation plan?
Source#2)
SUMMA : The retaining wall will be installed above the creek;therefore,no dewatering will
be necessary. Since the retaining wall will be constructed above the creek, spring and winter rain
salmon(Oncorhynchus tshawytscha),steelhead(Oncorhynchus mykfss),and other fish and
aquatic species,will not be impacted by the project. In addition,there are substantial
downstream migration barriers that prohibit migratory fish passage.
Red-legged frog(Rana aurora draytonii)are known to occur near the project site. As a
component of the environmental review under the National Environmental Policy Acct(NEPA),
the Federal Emergency Management Agency(FEMA)has conducted consultation with
representatives from the U.S. Fish and Wildlife Service(USFWS)regarding red-legged frog.
Based on the consultation,the project has been determined to be Not Likely To Adversely Affect
(NLTAA)the continued existence of the red-legged frog. This determination has associated
avoidance and minimization measures that must be implemented during construction of the
retaining wall in order to be valid. The measures include: 1) silt fencing or ether sediment
barriers will be placed to prevent soil from entering the creek during construction,2)heavy
equipment working near the water will be properly maintained such that oils and other fluids do
not leak and enter the creek, 3)work will be conducted between July 1 and November 1 or until
10 Potentially
Significant
Potentially Unless Cess than
Significant Mitigation Significant No
Im4act Ino-a oration I tt Imnact
the first fall rain producing 0.25 inch of rain occurs, 4)a qualified biologist(approved by
USFWS)will survey the project site and adjacent areas within 75 meters (246 feet)upstream and
downstream within 48 hours prior to the start of construction, 5)if red-legged frogs are present,
the County must notify USFWS. Per the FEMA consultation, all construction activities will be
stopped until the issue has been coordinated and resolved with USFWS. Although the County
(through FEMA)has obtained the NLTAA determination from USFWS, in order to avoid
potential construction delays associated with identifying frogs on the project site,the County will
obtain an incidental take permit from the USFWS to allow any identified frogs to be legally
relocated.from the project site. Based on the implementation of the avoidance and minimization
measures required by the consultation between USFWS and FEMA, and the fact that the County
will obtain an incidental tape permit from USFWS to allow red-legged frogs to be legally
relocated, impacts to red-legged frogs will be less than significant.
Construction activities associated with the project will impact the minimum amount of riparian
vegetation feasible. However, some tree and shrub removal may be necessary. In the area where
the retaining wall will be installed, approximately one bay(approximately 6"dbh) and two
willow trees(approximately 2"dbh)will require removal. In addition, approximately five coast
live oak trees(3—5"dbh) along Christie Road on the perimeter of the proposed wall may require
removal in order to construct an access road down the steep banks into the slide area and in order
to tie the wall back into the area adjacent to the road. Any trees that require removal will be
replaced at a 3:1 ratio with like species up to one gallon in size. The replacement trees will be
planted within the backfilled area above the retaining wall. The newly planted trees will be
maintained for a period of three years and monitored annually for a period of five years. At the
conclusion of the five year monitoring period,a survival rate of 75%will be required. If the
survival rate has not been achieved,additional plantings will occur. In order to minimize
damage to any additional trees that may be impacted by construction,contract specifications will
include protective measures such as clean trimming of roots and limbs. Activites associated with
the relocation of the roadway will impact non-native annual grasses and coyote brush shrubs.
Areas exposed as a result of the relocation of the roadway,as well as installation of the retaining
wall,will be seeded with a mix including native grasses and wildflowers.
Orange construction fencing will be installed to delineate the limits of construction impact at the
retaining wall location. The fencing will serve to isolate environmentally sensitive areas(ESAs)
from construction activities. The ESA fencing will be installed at the expected limits of
construction impact as delineated on the construction plans.
Activities associated with construction of the retaining wall will occur within California
Department of Fish and Game's jurisdiction. Public Works Department staff will coordinate
with staff from the agency regarding the project, and the appropriate agreement will be obtained
prior to implementation of the project. The County will comply with all conditions negotiated
for the agreement. According to a representative from the U.S. Army Corps of Engineers(pers.
11 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
IMMt Xn mgration
comm. E. Wylie, 3/31/99), construction of the retaining wall will not occur within Corps
jurisdiction. As a result,Water Quality Certification from the Regional Water Quality Control
Board is not required;however,the County will apply for a Waiver of Waste Discharge
Requirements under the Porter-Cologne Water Quality Control Act.
V. CULTURAL RESOURCES. Would the project:
a. Cause a substantial adverse change in the — X
significance of a historical resource as
defined in§15064.5?(Source#1,10)
b. Cause a substantial adverse change in the —
significance of an archaeological resource
pursuant to §1 5064.5?(Source#1,10)
C. Directly or indirectly destroy a unique i
paleontological resource or site or unique
geologic feature?(Source#1,10)
d. Disturb any human remains, including
those interred outside of formal cemeteries?
(Source#1,10)
IT, ; A records search conducted by the Northwest Information Center(NWIC)at
Sonoma State University indicated a moderate possibility of identifying Native American
resources in the project area. Based on this possibility,the KWIC researcher recommended
further study. Following further coordination with KWIC representatives(pens. comm.. L.
Jordan,2/18/00),it was agreed that in the case of a highly unstable site such as the Christie Road
Slide Repair project where field review would be potentially dangerous,it is appropriate for the
County to retain a qualified archaeologist to monitor any excavated material as it is stockpiled on
the road. Therefore,contract specifications for the project will require that a qualified
archaeologist be available during all excavation activities,including any excavation associated
with the roadway relocation,to monitor for potential cultural resources.
As a component of the environmental review under NEPA,the County is conditioned to confirm that
any fill material used for the project is taken from previously disturbed locations. If it is necessary
to utilize previously undisturbed sites,they must be reviewed by an archaeologist to ensure that no
cultural resources are impacted. The fill behind the retaining wall and any necessary access roads
may be obtained from a known"clean"(archaeological resource-free)borrow site along Cummings
Skyway. The borrow site has been determined to be clean since it consists of fill placed several
years ago as part of an earlier project. The contract specifications for the project will indicate that
if it becomes necessary to obtain fill material from the surrounding area or other previously
undisturbed borrow area,the County will be notified by the contractor and will immediately contact
12 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
jet Incorporation Inract l=act
NWIC for additional archaeological and historical research regarding the proposed borrow area.
In addition,the Resident Engineer for the project will receive instruction regarding identification
of archaeological and historical resources in the field.
VT. GEOLOGY AND SOILS-Would the
project?
a.' Expose people or structures to potential
substantial adverse effects,including the
risk of loss,injury,or death involving:
1.Rupture of a known earthquake fault,
as delineated on the most recent Alquist-
Priolo Earthquake Fault Zoning Map
issued by the State Geologist for the
area or based on other substantial evidence
of a known fault? Refer to Division of Mines
and Geology Special Publication 42.
(Source#1,2.,5,8)
2. Strong-seismic ground shaking? _ _
3. Seismic-related ground failure,including
liquefaction?(Source#1,2,5,8)
4.Landslides?(Source#1,2,5,8)
b. .Result in substantial soil erosion or the loss X _
T of topsoil?(Source#1,5,8)
C. Be bated on a geologic unit or soil that is r _
unstable,or that would become unstable as
a result of the project,and potentially result
in on-or off-site landslide,lateral spreading,
subsidence,liquefaction or collapse?
(Source#1,2,5,8)
d. Be located on expansive soil,as defined in
Table 18-1-B of the Uniform Building Code
(1994),creating substantial risks to life or
property?(Source#1,2,8)
e. Have soils incapable of adequately supporting X
the use of septic tanks or alternative waste
disposal systems where sewers are not available
for the disposal of waste water?(Source#N1A)
13 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
(g=t b22mgmjim 1=10t iMRact
Based on aerial photo documentation,the geotechnical consulting firm hired to review
the project site(Terrasearch)concluded that indications of the main slide(where the retaining wall
will be installed) occurred as early as 1982 when a small scarp can be identified on the photo.
Increased slope failure was observed in 1990, and by 1998, the slide appeared to be approximately
as severe as current conditions. Construction of the retaining wall and relocation of the roadway will
not expose people to adverse effects due to seismic activity. The Hayward Fault is located 6.8 miles
to the west and the Concord Fault is located 7.5 miles to the east of the project site. Both faults are
listed as active by the Alquist-Priolo Earthquake Fault Zones Act. The closest fault is the Franklin
Fault which is located approximately 1 mile from the project site. There are no active earthquake
fault zones at or in the immediately vicinity of the project site.
According to the Contra Costa County Soil Survey, soils in the vicinity of the project consist of
Altamont clay(15-30%slopes),Clear Lake clay, and Millsholm loam(30-50%slopes). Altamont
clay(15-30%slopes)is typically found on rolling hills,runoff is medium,and the hazard of erosion
is moderate where the soil is bare. This soil type is primarily used for range and dryland grain or
grain hay. Clear Lake clay is typically used for dryland small grain and volunteer hay production,
and runoff is very slow with no hazard of erosion where the soil is tilled and exposed. Millsholm
loam(30-50% slopes) is found on steep slopes; runoff is rapid and the hazard of erosion is high
where the soil is bare. Although the exact location of the main slide cannot be pinpointed on the Soil
Survey maps, it is highly likely,based on the extent of the erosion, the slide is located within the
Millshohn loam soil area. Bedrock beneath the slide area consists ofBriones Sandstone.
Grading and excavation associated with the retaining wall and roadway relocation will result in a
minor change in topography and temporarily increase the exposure of soils to wind erosion.
However, this is an insignificant and temporary impact. Adherence to standard dust control and
erosion control practices,including,but not limited to,general watering of exposed areas and/or use
of chemical stabilizers will minimize impacts. In addition, in order to address the highly erodible
soils in the retaining wall location,contract specifications will require the installation of silt fencing
or other effective sediment barrier below the raining wall construction area to prevent soil from
entering the creek due to construction activities. These measures will be incorporated into the
construction contract.
Superficial grading of the project area is not expected to result in unstable earth:conditions or change
geographical substructures. Exposure of people or property to geologic hazards is not expected to
increase as a result of the project. All areas left exposed due to construction of the retaining wall and
relocation of the roadway will be seeded with a mix including native grasses and wildflowers upon
completion of the project in order to stabilize exposed soil.
14 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
lmnact Incorporation impact Impact
VIS. HAZARDS AND HAZARDOUS MATERIALS -
Would the project:
a. Create a significant hazard to the public
or the environment through the routine
transport,use,or disposal of hazardous
materials?(Source#1,2,4,7,8,9)
b. Create a significant hazard to the public
or the environment through reasonably
foreseeable upset and accident conditions
involving the release of hazardous materials
into the environment?(Source#1,2,4,7,8,9)
C.. Emit hazardous emissions or handle
hazardous or acutely hazardous materials,
substances,or waste within one-quarter mile
of an existing or proposed school?
(Source#1,2)
d. Be located on a site which is included on a r i X
list of hazardous materials sites compiled
pursuant to Government Code Section 65862.5
and,as a result,would it create a significant
hazard to the public or the environment? 4
(Source#1,2,7)
e. For a project located within an airport land � � � X
use plan or,where such a plan has not been
adopted,within two miles of a public airport
or public use airport,would the project result in
a safety hazard for people residing or working in
the project area. (Source#2)
f. For a project within the vicinity of a private � � � X
airstrip,would the project result in a safety
hazard for people residing or working in the
project area? (Source#2)
g. Impair implementation of or physically
interfere with an adopted emergency response
plait or emergency evacuation plan?
(Source#1,2)
h. Expose people or structures to a significant _ X
risk of loss,injury or death involving wildland
fires,including where wildlands are adjacent
to urbanized areas or where residences are
intermixed with wildlands? (Source#1,2)
SUMMARY: The firm hired to review the project site for geotechnical issues(Terrasearch, Inc,
1/17100)identified petroleum hydrocarbon odors in three of the four borings taken near the
15 Potentially
Significant
Potentially Unless Fess than
Significant Mitigation Significant No
jet WOUNrat
project site. The borings were positioned in a linear pattern extending from the slide area, across
Christie Road and beyond the railroad. The boring taken within the slide area did not have a
petroleum hydrocarbon odor;however, the boring taken at the edge of Christie Road had a strong
odor at 6 meters(20 feet)below ground surface. In addition,the slide area is currently being
used as an illegal dumping ground for what appears to be typical household garbage,including
furniture,mattresses,used paint cans and other general garbage.
Based on these data and the presence of the garbage dump,the County hired Subsurface
Consultants (3/00)to perform follow-up soil and groundwater analysis at the project site to
determine if potentially hazardous substances were present. According to Subsurface's analysis,
concentrations of contaminants in the soil were relatively low and do not pose a significant
human health risk. However,results of the groundwater analysis suggest that groundwater
potentially encountered during construction or through a subdrain collection system may contain
detectable concentrations of TEHd(diesel fuel). The diesel fuel in the groundwater is suspected
to be the result of the nearby petroleum pipelines. Therefore, if groundwater is encountered
during construction,it will either be treated prior to release into the creek or off-hauled to an
appropriate treatment and/or storage facility. The specific treatment method utilized, such as
filtering the water through activated charcoal,will be at the discretion of the contractor.
However, if the contractor elects to treat the groundwater on site,contract specifications will
require that chemical testing of treated groundwater using US Environmental Protection Agency
(USEPA)Test Method 8015m(appropriate for testing of petroleum contamination)will be
implemented in order to ensure that the treatment process was effective. If the contractor elects
to off haul the groundwater for treatment, contract specifications will require the contractor
identify the appropriate treatment facility for approval by the Public Works Department.
Rather than installing a subdrain system behind the retaining wall that could potentially collect
and concentrate water containing TEHd,the County will install heavy gauge filter fabric behind
the retaining wall. The fabric will retain soil particles in place as groundwater continues to flow
through the soil. Groundwater will flow through the soil and retaining wall similar to existing
conditions, rather than collecting and concentrating in the subdrain system. Based on this design,
the existing hydrology at the project site will not change significantly. As a result,contamination
levels entering Rodeo Creek will not be significantly impacted by the project. The County will
forward Terraseach,Inc. and Subsurface Consultants' findings regarding the potentially
contaminated soil and groundwater to the operators of the nearby petroleum pipelines as well as
the railroad, since it is the property owner.
The project has the potential to release hazardous substances, such as accidental petroleum spills
from equipment, during construction. Per the contract specifications, standard construction
safety practices will,be followed during construction to ensure no accidental release of hazardous
substances or increase the potential for exposure to these substances.
16 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
Imp cz Incorporation IM= Impact
No interference with an emergency evacuation or response is expected to result from the project.
The majority of the work will occur within the slide area. Christie Road is rural and has minimal
traffic. Access to the homes at the end of Christie Road will be maintained at all times. Traffic
control measures around the work area will minimize the potential for accidents. Standard
specifications for the project will require installation of sufficient warning signs regarding the
construction and associated work hours.
VITT. HYDROLOGY AND WATER QUALITY-
Would the project:
a. Violate any water quality standards or _ X
waste discharge requirements?(Source#2,4,6,9)
b. Substantially deplete groundwater supplies X _
or interfere substantially with groundwater
recharge such that there would be a net
deficit in aquifer volume or a lowering
of the local groundwater table level(e.g.,
the production rate of pre-existing nearby
wells would drop to a level which would not
support existing land uses or planned uses
for which permits have been granted)?(Source#1,2,4,6)
C. Substantially alter the existing drainage X
pattern of the site or area,including through
the alteration of the course of a stream or river,
in a manner which would result in substantial
erosion or siltation on-or off-site?(Source#4,6)
d. Substantially alter the existing drainage i
pattern,of the site or area,including through
the alteration of the course of a stream or
river,or substantially increase the rate or
amount of surface runoff in a manner which
would result in flooding on-or qff site?
(Source#1,4,6)
e. Create or contribute runoff'water which X
would exceed the capacity of existing or
planned storm water drainage systems or
provide substantial additional sources of
polluted runoff?(Source#1,4,6)
f. Otherwise substantially degrade water X
quality?(Source#4,6,9)
g. Place housing within a 100-year flood X
hazard area as mapped on a federal Flood
Hazard Boundary or Flood Insurance Rate
Map or other flood hazard delineation map?
(Source#1,2,6)
17 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant NO
Immt lnor2mfion Irn= I1LlFg&.l
h. Place within a 100-year flood hazard area _ X _
structures which would impede or redirect
flood flows?(Source#1,4)
i. Expose people or structures to a significant
risk of loss,injury or death involving flooding,
including flooding as a result of the failure
of a levee or dam?(Source#1,2,4,6)
j, Inundation by seiche,tsunami,or mudflow?
(Source#1,4)
SUDIA.RY: The slides are located adjacent to Rodeo Creek. According to the Contra Costa
County Flood Control District Flood Insurance Rate Zone Information Map and the Resource
Mapping System,the project site is located in a floodplain. Neither the retaining wall nor the
relocated roadway will increase exposure of people or property to flooding. The wall will not
impair the flow of water;nor will it alter the course or flow of floodwaters. Installation of the
retaining wall-will reduce the amount of material entering the creek as a result of sliding;
therefore,the potential for flooding in and near the project area will be reduced. The amount of
surface water in Rodeo Creek will not change significantly as a result of the project. The minor
amount of additional impervious surfaces that the relocated road will add is insignificant. In
addition,building the retaining wall will not adversely affect the quantity or quality of surface
water, ground water or public water supply.
Measures will be undertaken in the design and construction of the retaining wall and the
relocation of the roadway to avoid adverse impacts to water quality. Contract specifications will
require the installation of silt fencing or other effective sediment barrier below the retaining wall
construction area to prevent soil from entering the creek due to construction activities. Contract
specifications will require the storage, servicing and fueling of construction equipment on the
road rather than in the slide area. Standard construction safety practices will be incorporated into
the project to reduce the possibility of a spill of gasoline,oil,or other pollutant that could have a
significant impact on water quality. In addition,stockpiled materials will be located far enough
from the banks of the channel to prevent construction materials from entering the creek.
Results of groundwater studies near the main slide area indicate that groundwater that could be
encountered during construction may contain detectable levels of TEHd(diesel fuel). If
groundwater is encountered during construction, it will either be treated prior to release into the
creek or off-hauled to an appropriate treatment and/or storage facility The specific treatment
method utilized, such as filtering the water though activated charcoal,will be at the discretion of
the contraction. However, if the contractor elects to treat the groundwater on site, contract
specifications will require that chemical testing of treated groundwater using USEPA Test
Method 8015m(appropriate for testing of petroleum contamination)will be implemented in
order to ensure that the treatment process was effective. If the contractor elects to off-haul the
18 Potentially
Significant
Potentially Unless less than
Significant Mitigation Significant No
t Ing2MgMtion fact imml
groundwater to an appropriate treatment or storage facility,contract specifications will require
the contractor identify the facility for approval by the Public Works Department.
Rather than installing a subdrain system behind the retaining wall that could potentially collect
and concentrate water containing detectable levels of TEHd,the County will install a heavy
gauge filter fabric behind the retaining wall. The fabric will retain soil particles in place as
groundwater continues to flow through the soil. Groundwater will flow through the soil and
retaining wall similar to existing conditions,rather than collecting and concentrating in the
subdrain system. Based on this design,the existing hydrology at the project site will not change
significantly. As a result,contamination levels entering Rodeo Creek will not be significantly
impacted by the project. The County will forward Subsurface Consultants' findings regarding
the potentially contaminated groundwater in the retaining wall location to the operators of the
nearby petroleum pipelines as well as the railroad, since they are the property owners.
Total disturbance due to construction of the retaining wall and relocation of the roadway will be
less than five acres. At the completion of the project, all disturbed areas will be stabilized
through the use of hydroseeding with a mix including native grasses and wildflowers and/or
erosion control blanketing, as appropriate.
The project site is not within Corps jurisdiction(pens. com. E. Wylie, 3/31/99); therefore, a
Corps permit and State Water Quality Certification will not be necessary;however,the County
will obtain a Waiver of Waste Discharge Requirements under Porter-Cologne from the Regional
Water Quality Control Board.
IX. LAND USE AND PLANNING-Would
the project:
a. Physically divide an established community?
(Source#2,4)
b. Conflict with any applicable land use plan, W _. ...3x.
policy,or regulation of an agency with
jurisdiction over the project(including,but
not limited to the general plan,specific plan,
local coastal program,or zoning ordinance)
adopted for the purpose of avoiding or
mitigating an environmental effect?
(Source#1,2,4)
C. Conflict with any applicable habitat _ X
conservation plan or natural community
conservation plan? (Source#1,2,4)
19 Potentially
Significant
Potentially Unless Less than
significant Mitigation Significant No
t I=m=Qn InwirA IM2V-t
The retaining wall will be constructed immediately adjacent to Christie Road in
order to stabilize the highly unstable slope. Left unchecked, the slide would likely continue to
move farther southwest,ultimately making Christie Road impassable. Constructing the retaining
wall will minimize further damage to Christie Road; thereby allowing for continued access to the
homes at the end of Christie Road. Capacity of the roadway as a result of the project will not
increase as a result of the project. In the two areas that will be addressed by relocating the
roadway,there is sufficient mom to ensure continued access by simply moving the road farther
away from the sloughing slopes. The project will not result in a substantial alteration of the
present or.planned land use of the area. The County General Plan defines Christie Road as a
local road with the existing land use surrounding the project being primarily agricultural. Since
Christie Road is located within the Burlington Northern Santa Fe Railroad right of way,if
required by the railroad,the County will obtain a right of entry from the railroad in order to
conduct the repair work associated with the retaining wall and road relocation.
The project is consistent with the County General Plan Transportation and Circulation Elements
Roadway and Transit Goals#5-A(To provide a safe, efficient and balanced transportation
system), Goal 5-B (To coordinate the provision of streets, roads,transit and trails with other
jurisdictions),Policy#5-9(Existing circulation facilities shall be improved and maintained by
eliminating structural and geometric design deficiencies). Repairing the road will not result in an
increase in population,displacement of people, or create a demand for additional housing.
X. MI ERAL RESOURCES-Would the
project:
a. Result in the loss of availability of a known Ji_ _
mineral resource that would be of value to
the region and the residents of the state?
(Source#1,2)
b. Result in the loss of availability of a locally-
important mineral resource recovery site
delineated on a local general plan, specific
plan or other land use plan? (Source#1,2)
SL504AR'Y, During construction,the project will use paving materials (i.e., asphalt),wood
products, concrete and other materials derived from natural resources;however,the project will
not significantly impact these resources. The use of oil and gasoline to operate the machinery for
construction purposes is negligible and of a short-term,temporary nature. In order to minimize
impacts due to construction activities,contract specifications will stipulate the elimination of
unnecessary idling of equipment when not in use.
20 Potentially
Significant
Potentially 'Unless Less than
Significant Mitigation Significant No
Impact lncration l=Nt ac
XI. NOISE-Would the project result in:
a. Exposure of persons to or generation of a X
noise levels in excess of standards established
in the local general plan or noise ordinance,
or applicable standards of other agencies?
(Source#2,4)
b. Exposure of persons to or generation of
excessive ground borne vibration or ground
borne noise levels?(Source#4)
C. A substantial permanent increase in X
ambient noise levels in the project vicinity
above levels existing without the project?
(Source#2,4)
d. A substantial temporary or periodic increase
in ambient noise levels in the project vicinity
above levels existing without the project?
(:source#2,4)
e. For a project located within an airport land X
use plan or,where such a plan has not been
adopted,within two mites of a public airport
or public use airport,would the project
expose people residing or working in the
project area to excessive noise levels?
(Source#N/A)
f. For a project within the vicinity of a private _ X
airstrip,would the project expose people
residing or working in the project area to
excessive noise levels?(Source#N/A)
SUMMARY: The dominant source of noise in the project area is produced by vehicles already
using Christie Road as well as trains on the adjacent railroad. Installation of the retaining wall
and relocation of the roadway will not increase the capacity of Christie Road. The existing road
is the only access to the homes beyond the slide area,therefore the ambient noise levels
associated with routine use of the road will remain the same.
Construction of the project will increase the noise level temporarily;however,there are no
sensitive receptors in the vicinity of the project. In general, construction activities produce noise
levels of 86 dBA at 50 feet which is well below the threshold of pain of 120-140 dBA. bile
installation activities associated with the retaining wall will occur over a period of approximately
two weeks. The piles will be installed through a drill and cast-in-place process(rather than pile
driving)that will reduce the amount of noise associated with the installation. Activities
associated with relocation of the roadway will have comparable noise levels to normal road
21 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
jet lneotzmWQn I IM21MI
overlay or reconstruction projects. Although the pile drilling activities will produce some ground
vibration, sensitive receptors are located far enough away from the project site that vibration will
not create a significant impact. Contract specifications will require the use of properly tuned and
muffled equipment to minimize other noise due to construction. Working hours will be limited to
7.30 am. to 5:00 p.m. Monday through Friday, unless modified upon written approval by the
resident engineer,to reduce construction noise levels. These working hours will be incorporated
as part of the construction contract.
XII. POPULATION AND HOUSING-
Would the project:
a. Induce substantial population growth in an __ _ _ IL
area,either directly(for example,by proposing
new homes and businesses)or indirectly(for
example,through extension of roads or other
infrastructure)?(Source#2,4)
b, Displace substantial numbers of existing
housing,necessitating the construction of
replacement housing elsewhere?
(Source#2,4)
C. Displace substantial numbers of people, ._
necessitating the construction of replacement
housing elsewhere?(Source#2,4)
The proposed project is located along an existing roadway. Installation of the
retaining wall and relocation of the roadway will not affect available capacity of Christie Road
and will,therefore,not induce population growth. The project will not result in the displacement
of any homes or residents. The project will not result in a change in the location,distribution,
density or growth rate of human population in the area. The project will not affect existing
housing, or create a demand for additional houses. The project will not require the removal of
any homes or the displacement of any people.
XIII. PUBLIC SERVICES
a. Would the project result in substantial
adverse physical impacts associated with
the provision of new or physically altered
governmental facilities,need for new or
physically altered governmental facilities,
the construction of which could cause significant
environmental impacts,in order to maintain
22 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
(Moe lncot =tion [mnact Impact
acceptable service ratios,response times or
other performance objectives for any of the
public services(Source#2,6}:
1. Fire Protection? X
2. Police Protection? X
3. Schools? ~_ _ X
4. Parks? X
5. Other Public facilities? X
The project is located within the Rodeo Fire Protection District and the John
Swett Unified School District. The retaining wall will be installed adjacent to the existing
roadway.and will not increase the capacity of Christie Road. Cance constructed,the new
retaining wall will not increase the need for fire or police protection, schools,parks or other
governmental services. In addition,relocation of the roadway will not increase the capacity of
Christie Road,nor will it increase the need for public services. During construction of the
retaining wall and relocation of the roadway, access will be maintained to the homes at the end of
Christie Road at all times. The majority of the work will be conducted in the main slide area;
therefore,heavy equipment will not block the entire roadway. Residents and emergency service
vehicles will be able to drive around the construction areas at all times.
The County currently maintains Christie Road and periodic maintenance of road improvements
will continue to be performed by the County.
XIV. RECREATION-
a. Would the project increase the use of X _
existing neighborhood and regional parks
or other recreational facilities such that
substantial physical deterioration of the
facility would occur or be accelerated?
(Source#1,2,4)
b. Does the project include recreational _ X
facilities or require the construction or
expansion of recreational facilities which
might have an adverse physical effect on
the environment? (Source#1,2,4)
SLTIV gARY: The County Resource Mapping System and the field reviews did not identify any
recreational opportunities in the immediate project area. There is a combination trail(hiking and
riding) identified by the Resource Mapping System that appears to parallel Rodeo Creek on the
opposite bank; however, the project will not impact recreational activities on the trail.
24 Potentially
significant
Potentially Unless Less than
Significant Mitigation Significant No
tmnact tncarooration Llm Itmpact
on the relatively small number of truck trips generated and the limited number of days over which
the trips will occur,the impact due to the transportation of fill is less than significant.
Christie Road is a local road that is the only access to several homes beyond the project site. The
project consists of installing a retaining wall to stabilize an existing sliding roadway and relocating
the roadway in two other unstable areas where it is feasible. There will be no substantial increase
to the width of the roadway,therefore, the project will not increase the capacity of Christie Road,
nor will it increase traffic on Christie Road. Although there will be additional traffic generated by
construction of the retaining wall and relocation of the roadway due to construction vehicles, the
traffic will be temporary and insignificant. The existing road and/or the area immediately adjacent
to the existing road will be kept in service during the project for resident and emergency services
access to the homes beyond the project site. At least one lane of Christie Road and/or additional area
immediately adjacent to Christie Road will be open at all times.
Following completion of the road relocation, reflective markers or pavement delineators will be
installed to clearly define the appropriate travel way along the newly relocated road.
The project will not alter waterborne,rail or air traffic as no water or air transportation facilities are
located in the immediate vicinity of the project area, and the project will not impact the railroad.
XVI. UT IMS AND SERVICE SYSTEMS -
Would the project:
a. Exceed wastewater treatment requirements X
of the applicable Regional Water Quality
Control Board? (Source#N/A)
b. Require or result in the construction of new �X_
water or wastewater treatment facilities
or expansion of existing facilities,the
construction or which could cause significant
environmental effects?(Source#N/A)
C. Require or result in the construction of new _ X
storm water drainage facilities or expansion
of existing facilities,the construction of which
could cause significant environmental effects?
(Source#N/A)
d. Have sufficient water supplies available to X
serve the project from existing entitlement
and resources,or are new or expanded
entitlement needed?(Source#N/A)
e. Result in a determination by the wastewater X
treatment provider which serves or may serve
23 Potentially
significant
Potentially Unless Less than
Significant Mitigation Significant No
[MRt Inc-2mon i'on I pact Impact
Surrounding land uses in the immediate vicinity of the project consist of undeveloped and
agricultural land.
XV. 'IR NSPORTATIOMRAFFIC-Would
the project;
a. Cause an increase in traffic which is
substantial in relation to the existing traffic
load and capacity of the street system (i.e.,
result in a substantial increase in either the
number of vehicle trips,the volume to capacity
ratio on roads,or congestion at intersections)?
(Source#1,2,4)
b. Exceed,either individually or cumulatively, X
a level of service standard established by
the county congestion management agency
for designated roads or highways?
(Source#1,2,4)
C. Result in a change in air traffic patterns, _ X
including either an increase in traffic levels
or a change in location that results in substantial
safety risks?(Source#N/A)
d. Substantially increase hazards due to a design _ X
feature(e.g., sharp curves or dangerous inter-
sections)or incompatible uses(e.g., farm
equipment)?(Source#1,2,4)
C. Result in inadequate emergency access? — _
(Source#1,2,4)
f. Result in inadequate parking capacity? — m X
(Source#NIA)
g. Conflict with adopted policies,plans,or — i __
programs supporting alternative transportation
(e.g.,bus turnouts,bicycle racks)?
(Source#2)
SUIVIMARY: Construction of the retaining wall will require importation of fill in order to backfill
the area behind the retaining wall. Approximately 2200 cubic yards of fill(or 183 truck loads)will
be required to adequately construct the retaining wall. The fill is expected to be imported over a
period of approximately 10 days,therefore,truck trips generated along Highway 4 and Christie Road
are expected to be approximately 20 trips a day over the 10 day period. Truck traffic will be required
to access Christie Road from eastbound Highway 4 and exit Christie Road to eastbound Highway
4;therefore,no left turns will be negotiated to access or exit the project site. Truck trips associated
with the potential off haul of groundwater encountered during construction will be negligible. Based
25 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
1111Mt Ing mfign 1M= IMRW
the project that it has adequate capacity to serve
the project's projected demand in addition to the
provider's existing commitments?(Source#N/A)
f. Be served by a landfill with sufficient
permitted capacity to accommodate the
project's solid waste disposal needs?
(Source#N/A)
g. Comply with federal,state and local statutes _A-L
and regulations related to solid waste?
(Source#N/A)
SIAS0RY: There is an abandoned petroleum pipeline running approximately perpendicular to
Christie Road on the edge of the slide area. The line will be cut off and recapped near the
roadway in order to facilitate construction of the retaining wall. In addition,there is an active
petroleum pipeline running under the project site,approximately in the middle of the slide area.
The retaining wall will be installed such that the piles of the wall straddle the gas line. The
owner of the pipeline will be notified regarding the proposed project and schedule, and a
representative from the pipeline company will be on-site during all construction activities
occurring near the petroleum line.
XVII. MANDATORY FINDINGS OF SIGNIFICANCE-
a. Does the project have the potential to degrade _ X
the quality of the environment, substantially
reduce the habitat of a fish and wildlife species,
cause a fish or wildlife population to drop below
self-sustaining levels,threaten to eliminate a
plant or animal community,reduce the number
or restrict the range of a rare or endangered
plant or animal or eliminate important examples
of the major periods of California history or
prehistory?
b. Does the project have impacts that are indiv- X
idually limited,but cumulatively considerable?
("Cumulatively considerable"means that the
incremental effects of a project are considerable
when viewed in connection with the effects of
past projects,the effects of other current projects,
and the effects of probable future projects)?
C. Does the project have environmental effects , _
which will cause substantial adverse effects on
26 Potentially
Significant
Potentially Unless Less than
Significant Mitigation Significant No
j t 1ncgMWtipn lnwaet jsts=
human beings,either directly or indirectly?
S M ARY:
The retaining wall will be difficult to see from Christie Road since to the top of the wall will be
approximately 10 feet below road grade. Construction activities associated with the retaining wall
will impact the minimum amount of vegetation necessary to complete the retaining wall;however,
approximately eight trees may require removal. All trees that are removed as a result of the
construction activity will be replaced at a 3:1 ratio in the backfilled area above the retaining wall.
Therefore, aesthetic impacts due to the project are less than significant.
California red-legged frog are known to occur near the project site,however,consultation between
FEMA and USFWS has resulted in a Not Likely To Adversely Affect determination for the project.
The avoidance and minimization measures required as a result of the consultation will reduce the
potential impact due to the project to a less than significant level. In addition,in order to minimize
potential construction delays due to identifiring frogs on the project site,the County will obtain an
incidental take permit from the USFWS to allow any identified frogs to be legally relocated from
the project site.
As a result of coordination with the Northwest Information Center,at Sonoma State University,the._
County will retain a qualified archaeologist to monitor any excavated material as it is stockpiled on
the road. In addition,the County will incorporate the requirement into the contract specification that
fill imported for use behind the retaining wall will either be obtained from a known clean borrow
site or alternative borrow sites will be researched to ensure that no cultural resources will be
impacted.
According to Subsurface Consultants, results of groundwater analysis suggest that groundwater
potentially encountered during construction or through a subdrain collection system may contain
detectable concentrations of TEHd. Groundwater encountered during construction will either be
treated prior to release into the creek or off-hauled to an appropriate treatment and/or storage facility.
The County will install a heavy gauge filter fabric behind the new retaining wall. The fabric will
retain soil particles in place as groundwater continues to flow through the soil. Based on this design,
the existing hydrology at the project site will not change significantly and contamination levels
entering Rodeo Creek will not be significantly impacted by the project. The County will forward
Terrasearch,.Inc. and Subsurface Consultants' findings regarding the potentially contaminated soil
and groundwater to the operators of the nearby petroleum pipelines as well as the railroad.
Contract specifications will require the installation of silt fencing or other effective sediment
barrier below the retaining wall construction area to prevent soil from entering the creek due to
construction activities. Contract specifications will require the storage, servicing and fueling of
27 Potentially
significant
Potentially Unless Less than
Significant Mitigation significant No
IrOgnt incorporation jet Im m
construction equipment on the road rather than in the slide area. Standard construction safety
practices will be incorporated into the project to reduce the possibility of a spill of gasoline,oil,
or other pollutant that could have a significant impact on water quality. In addition, stockpiled
materials will be located far enough from the banks of the channel to prevent construction
materials from entering the creek.
Truck trips generated along Highway 4 and Christie Road are expected to be approximately 20 trips
a day over the 10 day period. Truck traffic will be required to access Christie Road from eastbound
Highway 4 and exit Christie Road to eastbound Highway 4;therefore,no left tunas will be negotiated
to access or exit the project site. Truck trips associated with the potential ofd haul of groundwater
encountered during construction will be negligible. used on the relatively small number of truck
trips generated and the limited number of days over which the trips will occur,the impact due to the
transportation of fill is less than significant. Christie Road is a local road that is the only access to
several homes beyond the project site. Although there will be additional traffic generated by
construction of the retaining wall and relocation of the roadway due to construction vehicles, the
traffic will be temporary and insignificant. At least one lane of Christie Road and/or additional area
immediately adjacent to Christie Road will be open at all times.
There is an active petroleum pipeline running under the project site, approximately in the middle
of the slide area. The retaining wall will be installed such that the piles of the wall straddle the
gas line. The owner of the pipeline will be notified regarding the proposed project and schedule,
and a representative from the pipeline company will be on-site during all construction activities
occurring near the petroleum line.
As discussed in Sections II(Agricultural Resources),III(Air Quality),VI(Geology and Soils),IX
(Land Use and Planning),X(Mineral Resources),XI(Noise),XII(Population and Housing),XIII
(Public Services),XIV(Recreation),and XVI(Utilities and Service Systems),the proposed project
will not result in substantial adverse effects on human beings,either directly or indirectly.
g\enviro\200OProjects\ChristieRdS fide\NPGDEC
Dennis M.Berry,AICP
Co M m u n ity Contra o ntra Community Development Director
Development Cost.
Department County
County Administration Building MAYO 8 2000
651 Pine Street ;
4th Floor,North Wing •+ '
Martinez,California 94553-0095 S.L. WEIR. COUNTY CLERIC
C NIRA COS A COUNTY
Phone: B DEPUTY
NOTICE OF PUBLIC REVIEW AND INTENT TO ADOPT A PROPOSED NEGATIVE
DECLARATION
County File #CP 00-37
Pursuant to the State of California Public Resources Code and the "Guidelines for
implementation of the Califomia Environmental Quality Act of 1970" as amended to date, this is
to advise you that the Community Development department of Contra Costa County has
prepared an initial study on the following project.
CHRISTI,E ROAD SLIDE REPAIR PROJECT, County File# CPOO-37: Christie Road is located
above the northeastern bank of Rodeo Creek. The project will address three areas of bank
instability between Christie Road and Rodeo Creek. The first two areas will not be repaired.
Instead, since there is available area, the road will be relocated eastward toward the Burlington
Northern Santa Fe Railroad tracks and away from the sloughing bank. The road relocation will
extend approximately 1100 feet and will require minor roadway excavation, the placement of
base rock, the placement of asphalt concrete, extension of a cross culvert, and minor shoulder
grading.
The third slide area is an imminent threat to Christie Road and there is no suitable area to
relocate the road away from the sloughing bank (the railroad is closer to the creek in this
location). To prevent further erosion of the roadway into the creek, the slide will be repaired by
constructing a retaining wall longitudinally along Christie Road between the road and Rodeo
Creek. The retaining wall will be located parallel to Christie Road in a flat benched area created
by the sloughing material. The benched area is located approximately 20 feet below road
grade. The retaining wall will be approximately 9 feet high and will be located approximately 35
feet from the edge of the road and 15 feet from the top of bank of Rodeo Creek. The wall will be
approximately 295 feet long and the plies for the wall will be approximately 23 feet deep.
Earthen fill will be placed behind the retaining structure at a 2:1 slope up to road level.
Two petroleum pipelines run roughly perpendicular to the proposed retaining wall. One of these
pipelines pins approximately 10 feet below the road and has been abandoned and capped. The
second pipeline is active and runs approximately 23 feet under the project roughly in the middle
of the proposed retaining wall. The retaining wall will be installed such that the piles of the wall
straddle the gas line. The owner of the pipeline will be notified of the proposed project and
schedule, and a representative from the company will be on-site during all construction activities
occurring near the pipeline.
As a result of coordination with the Northwest Information Center at Sonoma State University,
the County will retain a qualified archaeologist to monitor any excavated material as it is
stockpiled on the road. In addition, the County will incorporate the requirement into the contract
specification that fill imported for use behind the retaining wall will either be obtained from a
Page 1 of 3
Office Hours Monday-Frday:8:00 a.m.-5:00 p.m.
Office is closed the 1 st, 3rd&5th Fridays of each month
known clean borrow site or alternative borrow sites will be researched to ensure that no cultural
resources will be impacted.
Results of soil and water sampling conducted at the project site indicate that groundwater that
could be encountered during construction, or collected by a subdrain system installed as a
.component of the retaining wall project, may contain detectable levels of TEHd (diesel fuel).
The diesel fuel is suspected to be the result of the nearby petroleum pipelines. If groundwater is
encountered during construction it will either be treated prior to release into the creek or off-
hauled to an appropriate treatment and/or storage facility.
Rather than installing a subdrain system behind the retaining wail that could potentially collect
and concentrate water containing detectable levels of TEHd, the County will install heavy gauge
filter fabric behind the retaining wall. The fabric will retain soil particles in place as groundwater
continues to flow through the soil. Based on this design (groundwater flow through the soil and
retaining wall similar to existing conditions, rather than collection and concentration of
groundwater in a subdrain system), the existing hydrology at the project site will not change
significantly due to the project. As a result, TEHd contamination levels entering Rodeo Creek
will not be significantly impacted by the project. The County will forward the results of the soil
and water sampling to the owner of the pipeline and the owner of the property(the railroad).
Construction activities associated with the retaining wall and road relocation will impact the
minimum amount of riparian vegetation necessary; however, some tree and shrub removal will
be necessary(approximately 8 trees may require removal). All trees that require removal will be
replaced at a 3:1 ratio with like species up to one-gallon in size. The replacement trees will be
planted within the backfilled area above the retaining wall and will be maintained for a period of
three years and monitored for a period of five years.
California red-legged frog are known to occur near the project site. The Federal Emergency
Management Agency (FEMA) has consulted with the U.S. Fish and Wildlife Service (USFWS)
regarding red-legged frog at the project site. Based on the consultation, the project has been
determined to be Not Likely To Adversely Affect (NLTAA) the continued existence of the red-
legged frog. This determination has associated avoidance and minimization measures that
must be implemented in order to be valid. The measures include: installation of silt fencing or
other sediment barriers to prevent soil from entering the creek, properly maintaining heavy
equipment to ensure that oils and other fluids do not leak and enter the creek; conducting work
between July i and November 9; retaining a biologist to survey the project site and adjacent
areas within 48 hours prior to the start of construction; and notifying USFWS if frogs are found
during the pre-construction survey. Although the County (through FEMA) has obtained the
NLTAA determination from USFWS, in order to avoid potential construction delays associated
with identifying frogs on the project site, the County will obtain an incidental take permit from the
USFWS to allow any identified frogs to be legally relocated from the project site.
The project is located within the California Department of Fish and Game's (CDFG)jurisdiction.
Public Works Department staff will coordinate with staff from CDFG to obtain a Streambed
Alteration Agreement prior to implementation of the project. The County will comply with all the
conditions negotiated for the permit. The project is not within the U.S. Army Corps of Engineers
jurisdiction. As a result, Water Quality Certification from the Regional Water Quality Control
Board is not required; however, the County will apply for a Waiver of Waste Discharge
Requirements under the Porter-Cologne Water Quality Control Act from the Regional Board.
Page 2 of 3
The existing road is the only access to several homes beyond the project site; therefore, access
beyond the project site must be maintained at all times to ensure that residents and emergency
services are not isolated by the project. At least one lane of Christie Road and/or additional
area immediately adjacent to Christie Road will be open at all times for through traffic. Since
Christie Road is located within the Burfington Northern Santa Fe Railroad right of way, if
required by the railroad, the County will obtain a right of entry from the railroad in order to
conduct the repair work associated with the retaining wall and road relocation.
Project Location: The Christie Road slide areas are located along Christie Road above Rodeo
Creek in central Contra Costa County. Christie Road is the only access to several homes..
The proposed project will not result in any significant impacts. A copy of the negative
declaration and all documents referenced in the negative declaration may be reviewed in the
offices of the Community Development Department, and Application and Permit Center at the
McBrien Administration Building, North Vying, Second Floor, 851 Pine Street, Martinez, during
normal business hours.
Public Comment Period — The period for accepting comments on the adequacy of the
environmental documents extends to Friday, June 9, 2000. Any comments should be in writing
and submitted to the following address:
Debbie Chamberlain, Principal Planner
Contra Costa County Community Development Department
651 Pine Street, North Wing, 4'h Floor
Martinez, CA 94553
Any questions regarding the project itself, should be directed to:
Leigh Chavez (925) 313-2366
Contra Costa County Public Works Department
255 Glacier Drive
Martinez, CA 94553
LC
g:tEn9SvciENVIRO\2000projectetChrietiertdSllde\Notice of Public Review.doc
Cc: County Clerk's office(2 copies)
Public Works—L.Chavez,Engineering Services
Page 3 of 3
j• �/�j Department
Maurice M.Shiu
Contra ' Public • �orks epa ent Public Works Director
Costa R.Mitch Avalon
255 Glacier Drive Deputy-Engineering
County Martinez,CA 94553-4825
Telephone: (925)313-2000 Jacqueline James
FAX: (925)313-2333 Acting Chief of Admin.Svcs.
June 14 2000 Patricia R.McNamee
Deputy-Operations
Mr. D.R. Quinn
Kinder Morgan Energy Partners, L.P.
1100 Town & Country Road
Orange, California 92868
Our File: Christie Road Slide Repair Project
Project Number: 0672-686351-98
Kinder Morgan File Reference#99-073-2
Dear Mr. Quinn:
Thank you for your comments on the Christie Road Slide Repair Project Negative Declaration
(CP#00-37). Following are responses to your comments:
1. Comment noted. The SFPP, L.P. Area Manager will be notified at least one week prior to
commencement of work near the pipeline.
2. Comment noted. This provision will be accommodated during the construction phase of the
work.
3. Comment noted. This provision will be accommodated during the construction phase of the
work.
SFPP, L.P. will be required to locate their 8-inch, high pressure refined petroleum product
pipeline during the design phase of the project as depth measurement to the pipeline will be
necessary in determining .the final design parameters. In addition, under the Underground
Service Alert (USA) regulations, the pipeline will also have to be located prior to any
construction. For further correspondence regarding the project, please contact Mr. Kevin Emigh
at (925) 313-2233 or kemiahO-ow.co.contra-costa.ca.us. Thank you.
Sincerely,
Lei Chavez
Planner
Engineering Services
LC:drf
G:\GrpData\EngSvc\ENVI RO\2000Projects\ChdstieMassSlide\RespKinderMorgan
Cc M.S. Rounds,SFPP, L.P.
K. Emigh, Design
C.Sellgren, Engineering services
KINDER ORGAN
ENERGY PARTNERS,L.P.
SPPP, L.P.
Operating Partnership June 5,2000
ENG 4-2-1 (13.87- 8) '
File Reference#99-073-2ar..
Ms.Leigh Chavez
Contra Costa County
Public Works Department
255 Glacier Drive
Martinez,CA 94553
RE: Christie Road Erosion Repair--Stabilization of the failed banks of Rodeo Creek
County File#00-37
Dear Mr.Chavez:
This is in reply to the "Notice Of Public Review And Intent To Adopt A Proposed Negative Declaration" that
concerns the proposed Christie Road slide repair project.
As you are aware SFPP'L.P. operates and maintains an 8-inch high pressure refined petroleum product pipeline at
the location where the proposed retaining wall will cross this facility.
In the interest of public safety and pipeline protection the following provisions must be considered in the design and
construction of the retaining wall:
1. Notify SFPP Area Manager, Mr. M.S. Rounds at(503) 224-3390 at least one week prior to commencement of
work near the pipeline. Mr. Rounds will arrange to have a pipeline representative present during pothole and
other site work near the pipeline.
2. Expose the 8-inch pipeline by hand excavation at point of the retaining wall crossing to determine exact
pipeline location prior to excavations utilizing power equipment. Pothole work must be performed by hand and
in the presence of a pipeline representative.
3. Provide a minimum 3 feet horizontal clearance between the piles and the 8-inch pipeline and a minimum 2 feet
clearance between the bottom of the retaining wall and top of the 8-inch pipeline.
1100 Town& Country Road Orange, California 92868 714/560-4400 714/560-4601 Fax
`5"
If you have any questions 1 can be reached at(714) 560-4940 and include the file reference number above with all
correspondence.
Sincerely,
,Y' `� j
D.R. Quinn
DRQIH:drgAeftm1WG4-2-1M-073-2,
cc: Ms.Bill Fernandez
Assooiate Civil Engineer
Design Division
Costa County
Public Works Department
255 Glacier Drive
Martinez,CA 94553-4897
M.S.Rounds
Contra Public Works Department Maurice Shia
Public woorr ks Director
Costa 255 Glacier Drive R.Mitch Avalon
Count-- Martinez,CA 94553-4825 Deputy-Engineering
_✓ Telephone: (925)313-2000 Jacqueline James
FAX: (925)313-2333 Acting Chief of Admin.Svcs.
Patricia R.McNamee
June 14, 2000 Deputy-Operations
Mr. Lester Nickleberry
1015 Christie Road
Martinez, CA 94553
Our File: Christie Road Slide Repair Project
Project Number: 0672-6R6351-98
Dear Mr. Nickleberry:
Thank you for your comments on the Christie Road Slide Repair Project Negative
Declaration (CP#00-37). Following are responses to your comments (see your attached
letter for corresponding question numbers):
1. The construction activites will have no significant impact to Rodeo Creek since the
repair will take place on the upper bench of the eroded area, and no water control
measures will be necessary. The design of the ultimate repair measure will not
divert or collect groundwater; instead, groundwater will be allowed to flow through
the implemented repair measure uninterrupted, similar to existing conditions.
Because the design of the repair measure will not significantly alter the existing
hydrology in the vicinity of the project site, the project will not affect well systems in
the area. Groundwater encountered during construction may be temporarily treated
prior to release into the creek or off-hauled to an appropriate treatment and/or
storage facility. However, the amount of groundwater collected during the treatment
or off-haul process will not have a noticeable effect on the groundwater supply in the
vicinity of the project site, and will; therefore, not impact well systems in the project
vicinity.
2. Relocation of a portion of the roadway (east of the main slide area adjacent to the
two smaller slides) will occur in September of 2000. Construction of the repair in the
main slide area will be conducted in the spring/summer of 2001.
3. Traffic control measures will be implemented during construction of the repair;
however, no lengthy delays are anticipated. Approximately 20 truck trips a day over
a 10 day period are expected during the project; however, truck traffic will be
required to access Christie Road from eastbound Highway 4 and exit Christie Road
to eastbound Highway 4; therefore, no left turns will be negotiated to access or exit
the project site (i.e`., traffic will not be delayed as trucks attempt to turn left to or from
Christie Road). The approximately 20 trucks trips a day are expected to be
staggered throughout the work day and, therefore, should not be centered around
any particular time of the day. Other construction-generated traffic (i.e., construction
crew members accessing site, etc.) is expected to be minimal. Based on the
directional requirements imposed on truck traffic, the limited amount of trips
generated as a result of the construction activites, and the temporary nature of the
repair activity, traffic impacts to Christie Road are expected to be minimal.
If you have any further questions, please call me at (925) 313-2366 or the design
engineer, Kevin Emigh, at (925) 313-2233. Thank you.
W&?ince ely,
Le Chavez
Planner
Engineering Services
LC:drf
G:\GrpData\EngSvc\ENVIR0\2000 projects\ChristleMassSlide\RespNickleberry.doc
cc K. Emigh,Design
C.Seligren, Engineering Services
[ENVIR
ecrvveb
4 A
UN 12 2000
June 9, 2000 NM A1�
Debbie Chamberlain, Principal Planner
Contra Costa County Community Development Dept.
651 Pine Street, North Wing,, 4`h Floor
Martinez CA 94553
Re: Christie Road Slide Repair Project
This project raises my concern for those residents that primarily use Well Systems as
their only means of supplying water to their residence. Will the repairs have any
sigmifrcant impact to the creels and its current water flow during the entire project?
I am a home owner,and my home is on a Well System.
Also, what is the proposed date to begin construction, and will the construction project
cause delays on leaving Christie Road in the a.m fours and returning in the p.rn. hours.?
Thank you,
r
Lester Nickleberry
June 9,2000 CUN 2Debbie Chamberlain,Principal Planner �`" A4,, N7'A� �
Contra Costa County Community Development rept. w'
651 Pine Street,North Wing, 4`h Floor
Martinez, CA 94553
Re: Christie Road Slide Repair P roject
Concerns:
This project raises my concern for those residents that ptimarily use Wei) �
Systems as their only means of supplying water to their residence. Will
construction have any affect on our Well Systems?
"hank you,
I- Nlckleber