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HomeMy WebLinkAboutMINUTES - 04052011 - D.1PDF Return D. 1 To:Board of Supervisors From:Catherine Kutsuris, Conservation & Development Director Date:April 5, 2011 Contra Costa County Subject:Wind Energy Conversion Systems Ordinance Amendment APPROVE OTHER RECOMMENDATION OF CNTY ADMINISTRATOR RECOMMENDATION OF BOARD COMMITTEE Action of Board On: 04/05/2011 APPROVED AS RECOMMENDED OTHER Clerks Notes: VOTE OF SUPERVISORS AYE:John Gioia, District I Supervisor Gayle B. Uilkema, District II Supervisor Mary N. Piepho, District III Supervisor Karen Mitchoff, District IV Supervisor Federal D. Glover, District V Supervisor Contact:Will Nelson, (925) 335-1208 I hereby certify that this is a true and correct copy of an action taken and entered on the minutes of the Board of Supervisors on the date shown. ATTESTED: April 5, 2011 David Twa, BY:June McHuen , Deputy RECOMMENDATION(S): A. OPEN the public hearing on proposed Ordinance No. 2011-04. B. RECEIVE testimony and CLOSE the public hearing. Agenda http://64.166.146.245/agenda_publish.cfm?id=&mt=ALL&get_... 1 of 4 5/10/2021, 12:03 PM RECOMMENDATION(S): (CONT'D) C. FIND, for purposes of compliance with the California Environmental Quality Act (CEQA) and the State and County CEQA Guidelines, that the proposed zoning text amendment is exempt from CEQA pursuant to CEQA Guidelines § 15061(b)(3). D. FIND that the proposed zoning text amendment, which modifies various sections of County Code Chapter 88-3 - Wind Energy Conversion Systems, is consistent with the County General Plan. E. ADOPT Ordinance No. 2011-04, revising development standards for residential and commercial wind energy conversion systems. F. DIRECT Department of Conservation & Development staff to file a Notice of Exemption with the County Clerk. FISCAL IMPACT: None. BACKGROUND: Introduction This is a hearing to consider a proposed zoning text amendment that would modify several sections of County Code Chapter 88-3 – Wind Energy Conversion Systems. Chapter 88-3 regulates development of Commercial and Residential wind energy conversion systems (WECS), more commonly known as 'wind turbines.' The proposed zoning text amendment includes: modifications to definitions and permitting procedures; the addition of a permitting mechanism that would allow the County to approve reductions to the minimum setback requirements for Commercial WECS; elimination of certain aesthetic standards for Commercial WECS; elimination of restrictions on hours of operation for Residential WECS; and the addition of several development standards for Residential WECS. The proposed zoning text amendment would apply to all unincorporated areas of Contra Costa County. Background The County’s WECS ordinance was adopted in 1985, at approximately the same time that the first commercial wind farms were being commissioned in the Altamont Pass Wind Resources Area (APWRA) that covers parts of Contra Costa and Alameda counties. The major elements of the ordinance are permitting requirements and procedures, development standards for commercial and residential WECS, and site reclamation requirements. The ordinance has never been updated. In September 2008 and February 2009 the Department of Conservation & Development received Land Use Permit (LUP) applications from two wind farm operators (NextEra Energy Resources and Pattern Energy) seeking to repower existing wind farms ("repower" means to remove obsolete turbines and related infrastructure, such as electrical collection lines, and replace them with new turbines and infrastructure) in the southeast portion of the County adjacent to Los Vaqueros Reservoir and Vasco Caves Regional Preserve. Given the heights of modern turbines, both applicants were concerned that adherence to the current setback regulations for Commercial WECS could render their projects infeasible. Staff indicated that it would study the issue and propose amendments to the WECS ordinance to provide relief from the setbacks requirements if such relief proved justified and appropriate. The proposed zoning text amendment does include the addition of a mechanism to provide relief from setback requirements. In December 2009 the Department was approached by Bergey Windpower Company, which manufactures small wind turbines for residential and agricultural use, requesting that the ordinance’s restriction on hours of operation for Residential WECS be deleted. Staff indicated that it would review the merits of this request. The proposed zoning text amendment does include a deletion of the hours of operation restriction. On January 1, 2010, Government Code §§ 65893–65899 (Gov’t Code Article 2.11) became effective. This statute regulates “‘small wind energy systems’ designed for onsite home, farm, and small commercial use.” The stated legislative intent of the statute is as follows: "It is the policy of the state to promote and encourage the use of distributed renewable energy systems and to limit obstacles to their use, and it is the intent of the Legislature that local agencies encourage the installation of distributed renewable energy systems by removing obstacles to, and minimizing costs of, permitting distributed renewable energy systems." The statute provides counties with authority to adopt ordinances regulating small wind energy systems. The statute establishes permitting procedures and requirements and prescribes development standards pertaining to minimum parcel size, maximum height, maximum setbacks, maximum noise levels, view obstruction, and system design, among other things. Ordinances adopted after the statute’s effective Agenda http://64.166.146.245/agenda_publish.cfm?id=&mt=ALL&get_... 2 of 4 5/10/2021, 12:03 PM date must be consistent with the statute, while ordinances adopted prior to the effective date are exempt. Contra Costa County’s WECS ordinance is exempt from the statute. However, because one of the stated goals of the statute is to “facilitate the implementation of consistent statewide standards to achieve the timely and cost-effective installation of small wind energy systems,” staff proposes changes to the WECS ordinance that will make it more, but not entirely, consistent with the state law. During review of the WECS ordinance, staff noticed that certain sections could benefit from minor reorganization and changes in wording. Thus, minor modifications that clarify and add specificity to the text of the existing ordinance are included in the legislation. The attachment titled, "Explanation of Proposed Amendments to County Code Chapter 88-3" provides a detailed explanation of each proposed modification to the ordinance. On January 25, 2011, the County Planning Commission considered the proposed zoning text amendment and voted 5-0 to recommend that the Board of Supervisors adopt the amendment as proposed by staff. California Environmental Quality Act Compliance Amendments to zoning ordinances qualify as projects under CEQA and are therefore subject to CEQA review. However, the Department has determined, with certainty, that adoption of the proposed modifications to County Code Chapter 88-3 will not have a significant effect on the environment and are exempt from CEQA pursuant to CEQA Guidelines Section 15061(b)(3), which reads as follows: "A project is exempt from CEQA if the activity is covered by the general rule that CEQA applies only to projects which have the potential for causing a significant effect on the environment. Where it can be seen with certainty that there is no possibility that the activity in question may have a significant effect on the environment, the activity is not subject to CEQA." The facts supporting the Department’s determination are as follows: 1. Many of the proposed ordinance modifications are nonsubstantive and are proposed only for the purpose of clarifying or adding specificity to the text. 2. Many of the proposed ordinance modifications have been proposed for the purpose of achieving consistency with California Government Code §§ 65893–65899. In passing this statute, the State Legislature found that wind energy, when converted to electricity, reduces the state’s dependence on nonrenewable energy resources, reduces air and water pollution associated with burning fossil fuels, and reduces greenhouse gas emissions, all of which are environmentally beneficial. 3. Several of the proposed ordinance modifications, such as the five-decibel reduction in the noise limit for Residential WECS and the additional development standards for Residential WECS, would tighten regulations already aimed at reducing or eliminating environmental impacts. 4. There are only two regulatory areas, setbacks and site aesthetics, where the proposed modifications may be construed as making the ordinance weaker or increasing the likelihood of occurrence of an environmental impact. The modifications to these areas do not automatically confer any additional rights or entitlements upon a property owner or project applicant. The changes in these areas relate only to Commercial WECS, which themselves require approval Land Use Permits and are therefore subject to CEQA review. Any potential environmental impacts associated with Commercial WECS projects would be addressed through project-specific CEQA review processes, and would be subject to mitigation if found to be significant. County General Plan Consistency WECS and wind farms are discussed in policies 3-68 through 3-71 of the General Plan’s Land Use Element, and in policies 8-49 through 8-51 of the Conservation Element. Most of these policies discuss wind energy projects on a macro scale. The only policy that discusses the WECS ordinance itself is Policy 8-51, which reads as follows: "All new wind turbine applications shall comply, at minimum, with the site-specific criteria included in the wind energy conversion systems regulations in the County Ordinance Code." Policy 8-51 is the only policy that has any bearing on the proposed ordinance modifications. This policy only discusses the WECS ordinance in broad terms and does not mention any of the ordinance’s specific requirements. Therefore, the proposed modifications to the ordinance are found to be consistent with this policy and by extension are found to be consistent with the General Plan. Agenda http://64.166.146.245/agenda_publish.cfm?id=&mt=ALL&get_... 3 of 4 5/10/2021, 12:03 PM Summary and Conclusion Contra Costa County’s WECS ordinance has not been updated since its adoption in 1985. Since then, wind turbine technology has advanced significantly, focused studies have resulted in much better understanding of the impacts of wind turbines on avian species, and the State of California has adopted policies requiring procurement of a significant portion of its electricity from renewable sources. To achieve its goal of reducing reliance on fossil fuels, the state has also passed legislation aimed at streamlining the permitting process for small wind energy systems. All of these factors are taken into account in the proposed modifications to the WECS ordinance. Additionally, the Department has found the proposed modifications to be consistent with the goals and policies of the County General Plan and determined with certainty that adoption of the proposed modifications will not result in a significant impact on the environment. For these reasons, staff recommends that the Board of Supervisors adopt the proposed zoning text amendment modifying County Code Chapter 88-3. CONSEQUENCE OF NEGATIVE ACTION: If the Board of Supervisors does not adopt the proposed amendments to County Code Chapter 88-3, then the text of the Wind Energy Conversion Systems ordinance will remain in its current form. CHILDREN'S IMPACT STATEMENT: No impact. CLERK'S ADDENDUM Speakers: Terrence Cantorna, Tres Vaueros; Eric Zell, NextERA Energy; Brad Olson, East Bay Regional Park District. CLOSED the public hearing; FOUND for purposes of compliance with the California Environmental Quality Act (CEQA) and the State and County CEQA Guidelines, that the proposed zoning text amendment is exempt from CEQA pursuant to CEQA Guidelines § 15061(b)(3); FOUND that the proposed zoning text amendment, which modifies various sections of County Code Chapter 88-3 - Wind Energy Conversion Systems, is consistent with the County General Plan; ADOPTED Ordinance No. 2011-04, revising development standards for residential and commercial wind energy conversion systems; and DIRECTED Department of Conservation & Development staff to file a Notice of Exemption with the County Clerk. AgendaQuick©2005 - 2021 Destiny Software Inc., All Rights Reserved Agenda http://64.166.146.245/agenda_publish.cfm?id=&mt=ALL&get_... 4 of 4 5/10/2021, 12:03 PM EXPLANATION OF PROPOSED AMENDMENTS TO COUNTY CODE CHAPTER 88-3 Ordinance text proposed for deletion is indicated by strikethrough; text proposed for insertion is indicated by underline. All ordinance text, whether existing or proposed, appears in italics. Explanations of the proposed changes appear after the ordinance text. Section 88-3.206 Definitions. (1) “Commercial WECS” means two or more a WECS on one parcel or adjoining parcels under common ownership constructed for the purpose of generating electricity for sale to a public or private utility or to an offsite consumer. The changes to Section 88-3.206 are proposed for the purpose of describing Commercial WECS more accurately. (2) “Exterior project boundary” means all property lines that define the boundaries of a parcel upon which at least one Commercial WECS is constructed. If a Commercial WECS project involves two or more contiguous parcels, then “exterior project boundary” means the property lines that define the outside edge of the entire conglomeration of parcels. Section 88-3.602(a) of the current WECS ordinance, which establishes the setback requirements for Commercial WECS, states that setbacks shall be measured from “exterior project boundaries.” However, no definition of the term is provided. Setbacks are typically measured from lot lines, but wind farm developers have suggested that the exterior project boundary can also mean the boundaries of easements adjacent to and associated with a wind farm. This definition is proposed for the purpose of eliminating confusion over the base measurement point for setbacks. (2 3) “Machine Height” means the height of the tower and vertical distance measured from grade at the base of a WECS to the highest vertical extension of the WECS., including the uppermost extension of any blades. The below-grade portion of the foundation is excluded when measuring machine height. These changes are proposed for the purpose of clarifying the definition of “height” and making it generally consistent with Government Code § 65894(3), which defines “(small wind energy) system height.” (3 4) “Residential WECS” means one a WECS on a parcel of land when that is used only as an accessory to an allowable residential or agricultural use and has a rated capacity of not more than 50 kilowatts. The 50-kilowatt limitation is proposed in order to achieve consistency with Government Code § 65894(2), which defines a “small wind energy system.” Other minor changes are proposed for the purpose of improving readability. (5) “Tower Height” means the vertical distance measured from grade at the base of a WECS to the top of the fixed portion of the WECS, excluding the wind turbine. The below-grade portion of the foundation is excluded when measuring tower height. This new definition is proposed for the purpose of achieving consistency with Government Code § 65894(4). (4 6) “Wind energy conversion system” and “WECS” mean a machine, such as a wind turbine or windmill, which that converts the kinetic energy in the wind into a usable form of mechanical or electrical energy. These terms “WECS” includes all parts of the conversion system and the tower upon which the system is installed, but does not include power transmission equipment. The changes to the definition of “WECS” are proposed in order to improve the ordinance’s readability. Section 88-3.402 Use Permit – Required for Commercial WECS. No A person shall may not establish, maintain, or expand a Commercial WECS without first obtaining a land use permit as specified in this chapter, Title 8, and Chapter 26-2. Section 88-3.404 Use Permit – Residential WECS Exempted. A Residential WECS is exempt from the provisions of this chapter, except for rotor safety, tower access, electromagnetic interference, noise, and aesthetic standards. A Residential WECS may operate only between the hours of eight a.m. and six p.m. (a) A land use permit is not required to establish, maintain, or expand a Residential WECS. (b) A person may not establish, maintain, or expand a Residential WECS without first obtaining a building permit as specified in Title 7. (c) A Residential WECS must comply with the rotor safety, tower access, electromagnetic interference, noise, and aesthetic standards specified in this chapter, and must comply with the additional Residential WECS standards specified in Section 88-3.622. The changes proposed to Sections 88-3.402 and 88-3.404 are not substantive; their purpose is to clarify the text by making it more direct. Section 88-3.602 Commercial WECS Setback Requirements. (a) Setbacks from adjacent parcels. A minimum WECS setback of three times overall machine height (measured from grade to the top of the structure, including the uppermost extension of any blades) or five hundred feet, whichever is greater, shall be maintained from exterior project boundaries. (b) Setbacks from offsite residence(s) on adjacent parcels. In all cases, regardless of parcel areas, a minimum WECS setback of one thousand feet, from any existing legal offsite residence(s) or general plan designated residential areas, shall be maintained. (a) Except as provided in subsection (b) of this section, a Commercial WECS must be set back from each line of the exterior project boundary, and from each public right-of-way, a distance equivalent to three times the machine height or 500 feet, whichever is greater. (b) A proposed Commercial WECS that does not meet the minimum setback requirements of subsection (a) may be approved only if the following findings are made in addition to the findings required under Section 88-3.418: (1) The proposed Commercial WECS will not pose a significant danger to adjacent land uses due to toppling or blade-throw. 2 (2) The proposed Commercial WECS will not pose a significant danger to a public or private right-of-way due to toppling or blade-throw. (3) A reduced setback is necessary in order to avoid or reduce the severity of an environmental impact or to significantly increase the ability to utilize the kinetic energy of the wind resource. (c) Notwithstanding the provisions of subsections (a) and (b), a Commercial WECS must be set back at least 1,000 feet from all existing legal offsite residences and from all general plan- designated residential areas. Subsections (a) and (c) contain the original text of the ordinance. The only substantive change to these subsections is that subsection (a) now specifies that setbacks must also be maintained from public rights-of-way. The major change to the text of this code section is the addition of subsection (b), which establishes a mechanism to approve setback reductions for Commercial WECS where no such mechanism currently exists. Staff considered the following six factors in making the recommendation to add this mechanism to the ordinance. 1. Turbine Size When the WECS ordinance was adopted it was rare for turbine heights to exceed 200 feet. Because the setback requirement for Commercial WECS is three times the total machine height or 500 feet, whichever is greater, setbacks normally would have been between 500 and 600 feet. However, modern turbines approach 430 feet in total height, meaning that the minimum setback requirement for these turbines is nearly 1,300 feet. Such deep setbacks are not always necessary, such as when WECS projects abut one another. When other factors such as turbine spacing requirements and protection of avian species come into play, unnecessarily deep setbacks can cause significant difficulty in siting turbines. 2. Turbine Spacing Requirements The turning rotors of wind turbines create turbulence in the wind flow. Wind turbines do not operate as efficiently in turbulent wind and maintenance costs increase due to the vibration. Thus, turbines should be spaced far enough apart both laterally and axially to allow dissipation of the turbulence before the wind passes the next turbine. Rotor size is one of the main determinants of the spacing between turbines. The spacing requirement is generally a function of rotor diameter, which means that as turbines have become larger, the minimum distances required between them have become greater. As a rule of thumb, the minimum lateral spacing is two rotor diameters and the minimum axially spacing is seven rotor diameters. For the largest turbines, this equates to minimum spacing of approximately 660 feet laterally and 2,300 feet axially. The minimum spacing and setback requirements can combine to restrict turbine siting and layout options considerably. 3. Impacts on Avian Species The impact of wind turbines on avian species was largely unknown when the first turbines were installed in the APWRA, but is better understood today thanks to a concerted effort to study the issue. It is estimated that between 1,700 and 4,700 birds are killed annually by turbines in the APWRA. Many of these are raptors, including protected species such as golden eagles and red- tailed hawks. Reducing bird kills has now become a primary consideration when determining turbine locations. As a result of recent studies, flight paths and behaviors can be modeled and 3 areas where turbines would be most harmful to birds can be identified. Flexible setback regulations would help wind farm developers to avoid high-risk areas, thereby reducing avian mortality. 4. Reduced Hazards Associated With Modern Wind Turbines Setbacks help to protect nearby properties against potential hazards associated with wind turbines, specifically toppling (a turbine falling over) and blade throw (detachment of a turbine blade or fragment thereof). To guard against toppling, a setback of 1.1 to 1.25 times the height of the turbine is usually sufficient. However, turbine blades and blade fragments can be thrown great distances. Several studies, including the California Energy Commission’s (CEC) “Permitting Setback Requirements for Wind Turbines in California,” suggest a relationship between turbine height and potential blade throw distances. Calculations of example turbines used to evaluate the maximum attainable throw distance show a drop in the maximum throw distance with increasing turbine size. For large turbines of at least 325 feet (100 meters) in total height, the maximum throw range is estimated to be approximately equal to the turbine height for a full blade and 2.5 times the turbine height for a blade fragment. For smaller wind turbines the blade throw distances are estimated to be approximately 2.8 and 5.5 times the turbine height for a full blade and blade fragments, respectively. Thus, the County’s current setback requirement is consistent with the estimated throw distance for large turbines. However, the same CEC study also found that the probability of the type of failure that could lead to blade throw is within the range of 1-in-1000 per turbine per year. The Department is currently processing two LUP applications that together propose removal of 529 small and obsolete turbines and installation of 53 to 71 large modern turbines. By applying the failure probability cited in the CEC study to the proposed projects, one could conclude that a blade or blade fragment would be thrown from the new turbines, as a whole, once every 14 to 18.8 years. Because the current setbacks cover the anticipated blade throw distance, for this to be of consequence the throw would have to occur from a turbine that was granted a setback reduction. A conservative estimate, based on the proposed turbine layouts, is that 17 out of 53 turbines or 22 out of 71 turbines would not comply with the County’s existing setback regulations. For those 17 or 22 turbines, the incidence of blade throw would be once every 58.8 or 45.4 years, respectively. Because the lifespan of a modern wind farm is anticipated to be approximately 30 years, it is statistically unlikely that any of the proposed turbines for which a setback had been granted would throw a blade or blade fragment prior to being decommissioned at the end of its useful life. 5. Setback Regulations in Other California Counties Staff has reviewed the WECS setback requirements for Alameda, Kern, Merced, Riverside, San Diego, Santa Barbara, and Solano counties and found that while there are many characteristics common to the regulations, the setbacks themselves vary greatly. Excluding Merced County, the common characteristics are: (1) setback distances are based primarily on a multiplier of the total WECS height; (2) setbacks are measured from property lines or project boundaries, dwellings, and rights-of-way; and (3) mechanisms exist for granting setback reductions. Merced County is unique in that the setbacks for WECS are the same as those for regular buildings and structures in agricultural zones, being as shallow as 15 feet, but may be increased if it is determined by the planning commission or planning director that additional setbacks are necessary to make the use compatible with surrounding properties and uses. 4 Despite the common characteristics, the range in the required setback distances is wide. For instance, in Santa Barbara County the height multiplier for setbacks from property lines is 1.0, while the multiplier in San Diego County is 4.0 or 9.0 depending on conditions. Riverside County has the most comprehensive regulations and setbacks there range from a multiplier of 1.1 from some property lines to a fixed distance of ⅔-mile from a stretch of State Route 111 designated as a scenic resource. Alameda and Solano counties have adopted requirements that are very similar to Contra Costa’s, yet both allow for setback reductions. Staff found that the minimum setback distances specified in Contra Costa County’s existing WECS ordinance are consistent with the distances required by several other counties, including those with the largest wind farms in the state. The major difference is that Contra Costa’s existing ordinance lacks a mechanism to allow setback reductions. Thus, inclusion of such a mechanism would bring the County’s ordinance more into line with the requirements of other California counties. 6. California Renewables Portfolio Standard The California Renewables Portfolio Standard (RPS) established by the state legislature in 2002 and accelerated in 2006 required investor-owned utilities and electric service providers to increase procurement from eligible renewable energy resources until they reached 20 percent by 2010. In September 2009 Governor Schwarzenegger signed Executive Order S-21-09 directing the California Air Resources Board to adopt regulations requiring 33 percent of electricity sold in the state to come from renewable sources by 2020. Electricity produced by wind farms in Contra Costa County is sold to PG&E, which has not yet met the RPS requirements. Allowing more flexibility in wind farm design could help to increase electrical generation, which in turn would move the state closer to its renewable energy procurment goals. In light of these factors, staff proposes that the WECS ordinance be amended to allow setback reductions for Commercial WECS if all three of the supplemental LUP findings enumerated in subsection (b) can be met (these findings would be in addition to the seven standard LUP findings required to approve a Commercial WECS project). The first two findings are concerned with safety and are self-explanatory; they require confirmation that Commercial WECS with reduced setbacks would not pose a significant danger to adjacent land uses or public or private rights-of-way due to toppling or blade throw. The third finding requires confirmation that a setback reduction is necessary to avoid or reduce the severity of an environmental impact or to significantly increase the ability to capture and convert the energy in the wind. The purpose of the third finding is to ensure that a public benefit is realized, in the form of either reduced environmental degradation or increased production of renewable energy, in return for granting a setback reduction. Section 88-3.612 Noise. No WECS shall create noise which exceeds a maximum of sixty-five dBA as measured at the lot line. Measurement of sound levels shall not be adjusted for, or average with, non-operating periods. In the event noise exceeds this standard, the WECS operator shall take all measures necessary to meet this standard, which may include discontinued operation of one or more WECS. A site-specific noise study may be required to confirm compliance with the sixty-five dBA noise standard. Variances from this standard may be granted along property boundaries adjacent to existing or approved WECS where existing residences or general plan designated residential areas will not be adversely affected. 5 (a) Except as provided in subsection (b) of this section, a Commercial WECS may not generate or emit any noise at any time that exceeds a maximum level of 65 decibels (dBA), as measured at each line of the exterior project boundary. (b) A Land Use Permit issued for a Commercial WECS may authorize a maximum noise level that exceeds the level specified in subsection (a) if the Commercial WECS is adjacent to an already- existing or approved Commercial WECS and upon a finding that existing legal offsite residences and general plan-designated residential areas will not be adversely affected. (c) A Residential WECS may not generate or emit any noise at any time that exceeds a maximum level of 60 decibels (dBA), as measured at each line of the parcel upon which the Residential WECS is installed. (d) The measurement of Commercial or Residential WECS noise levels may not be adjusted for, or averaged with, periods of non-operation of the WECS. A site-specific noise study may be required to confirm compliance with the applicable noise standard. If noise generated or emitted by a Commercial or Residential WECS exceeds the applicable standard, the WECS operator must take measures necessary to comply with the standard, which may include discontinued operation of one or more WECS. The 65-decibel limitation specified in subsection (a) is carried over from the existing ordinance. The 60-decibel limitation in subsection (c) is proposed in order to achieve consistency with Government Code § 65896(b)(4) and represents a 5-decibel decrease from the County’s current standard for Residential WECS, meaning Residential WECS would now have to be quieter. The language in subsection (d) is carried over from the existing ordinance, with minor changes to improve readability. Most of the language in subsection (b) is taken from the existing ordinance. However, subsection (b) changes the mechanism for permitting an exceedance of the maximum noise level for Commercial WECS from a variance to an additional LUP finding. This additional finding would be similar to the supplemental LUP findings that would be used to approve reduced setbacks in that it would be applicable only if a proposed project did not comply with the noise standard. The reason for this change is that the findings to approve a variance, which are specified in Government Code § 65906 and County Code § 26-2.2006, are nonspecific and inflexible. The Department desires a specific finding to be made in order to allow a noise level exceedance and the best way to accomplish this is through adoption of a new LUP finding explicitly worded for this purpose. Section 88-3.618 Site Aesthetics. (a) Each WECS (towers and blades) structures and fencing shall must be of a nonreflective, and unobtrusive color. (b) All WECS, buildings, and structures related to a WECS shall must be sited to minimize visual impact to residences within one mile, adjacent roadways, and County scenic routes. This may require relocation of one or more WECS. The proposed changes in subsection (a) are non-substantive except for deletion of the requirements related to fencing. The reason for the deletion is that in practice the regulation is moot. All existing and proposed WECS project sites in Contra Costa County are owned by entities other than the wind farm operators and these entities have typically installed fencing for purposes, such as livestock containment, that are not necessarily related to the WECS projects. 6 Regarding the proposed changes to subsection (b), when the WECS ordinance was adopted turbines were relatively short and it was feasible to reduce their visibility by locating them behind ridges and in topographic low spots. However, two things have occurred that make compliance with the existing ordinance both improbable and perhaps undesirable. First, many turbine models are now 400+ feet in height with rotor diameters in excess of 300 feet, which makes it nearly impossible to minimize their visibility. Second, studies of avian flight patterns and behavior have shown that one way to minimize avian mortality is to avoid topographic low spots such as valleys, saddles, and ravines when siting turbines. Thus, attempting to reduce the visibility of turbines by placing them in these low spots could inadvertently exacerbate the severity of biological impacts. Section 88-3.622 Additional Residential WECS Standards. (a) Parcel size. The minimum size of a parcel on which a Residential WECS may be installed is one acre. A Residential WECS need not be on the same parcel as the primary residential or agricultural use, but the parcels must be under common ownership. Subsection (a) is proposed for adoption in order to achieve general consistency with Government Code § 65896(b)(1). The Government Code also requires the parcel to be outside of an “urbanized area” as defined by the U.S. Census Bureau and does address ownership. The Department chose not to include the “urbanized area” requirement because it is based on population density, which can change rapidly. The ownership clause is intended to provide flexibility for owners of multiple parcels. As the County currently has no minimum parcel size requirement for Residential WECS, adoption of this change would constitute a tightening of regulations. (b) Tower height. The maximum tower height for a Residential WECS located on a parcel with an area between one and five acres is 80 feet. The maximum tower height for a Residential WECS located on a parcel larger than five acres is 100 feet. Subsection (b) is proposed for adoption in order to achieve consistency with Government Code § 65896(b)(2). The County Code does not restrict the height of Residential WECS. Therefore, adoption of this change would constitute a tightening of regulations. (c) Hours. A Residential WECS may operate during all hours. County Code § 88-3.404 currently limits the operating hours for Residential WECS from 8:00 a.m. to 6:00 p.m. The purpose of this restriction is to limit potential noise impacts. However, Government Code § 65896(b)(4) limits noise from small wind energy systems to 60 decibels, which is 5 decibels lower than the County’s current standard for Residential WECS. If the proposed changes to County Code § 88-3.612 are adopted, then the County’s noise standard will be the same as the state’s, which constitutes a tightening of the County’s standard. The 60-decibel limit adopted by the state is presumed to be sufficiently low to mitigate potential noise impacts, especially when combined with the new minimum parcel size requirement of one acre. Therefore, staff has proposed deletion of the hours of operation restriction from County Code § 88-3.404 and proposes adoption of subsection (c) in order to affirm that deletion. (d) Capacity. The rated capacity of a Residential WECS may not exceed 50 kilowatts. Subsection (d) is proposed for adoption in order to achieve consistency with Government Code § 65894(2). As the County currently has no capacity limitation for Residential WECS, adoption of this change would constitute a tightening of regulations. 7 (e) Setback. A Residential WECS must be set back, from each property line of the parcel upon which the Residential WECS is located, a distance equivalent to the machine height of the Residential WECS. Subsection (e) is proposed for adoption in order to achieve consistency with Government Code § 65896(b)(3). The County currently requires compliance with the setbacks for the zoning district in which a Residential WECS is proposed. Thus, adoption of this change would constitute a tightening of regulations in instances where the height of the Residential WECS exceeded the minimum setback requirements for the zone, which would be almost all instances. 8