Volume I Walnut Creek BART Transit Village Draft EIR. for the City of Walnut Creek

Transcription

1 Volume I Walnut Creek BART Transit Village Draft EIR for the City of Walnut Creek SCH # July 18, 2012 Draft EIR

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3 July 18, 2012 Draft EIR Volume I Walnut Creek BART Transit Village Draft EIR for the City of Walnut Creek Prepared By: 1625 Shattuck Avenue, Suite 300 Berkeley, California Tel: Fax: In Association With: AECOM Illingworth & Rodkin

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5 TABLE OF CONTENTS 1. INTRODUCTION REPORT SUMMARY PROJECT DESCRIPTION ENVIRONMENTAL EVALUATION AESTHETICS AIR QUALITY CULTURAL RESOURCES GEOLOGY AND SOILS HAZARDS AND HAZARDOUS MATERIALS HYDROLOGY AND WATER QUALITY LAND USE AND PLANNING NOISE POPULATION, HOUSING, AND EMPLOYMENT PUBLIC SERVICES AND RECREATION TRANSPORTATION AND TRAFFIC UTILITIES AND SERVICE SYSTEMS GREENHOUSE GAS EMISSIONS ALTERNATIVES CEQA-REQUIRED ASSESSMENT CONCLUSIONS REPORT PREPARATION REFERENCES i

6 TABLE OF CONTENTS Appendices Appendix A: Appendix B: Appendix C: Appendix D: Appendix E: Appendix F: Appendix G: Appendix H: Appendix I: NOP and Comments Air Quality Data Geotechnical Report Phase I Environmental Site Assessment Noise Data Memorandum of Understanding/Cooperative Policing Agreement: BART Police Department and Walnut Creek Police Department Greenhouse Gas Emission Data Water Supply Assessment Traffic Data ii

7 BART CITY OF WALNUT CREEK TRANSIT VILLAGE DRAFT EIR TABLE OF CONTENTS List of Figures Figure 3-1 Aerial View of Existing Development on the Project Site Figure 3-2 Proposed Mixed Use Transit-Oriented Development Figure 3-3 Proposed Site Plan Ground Level Figure 3-4 South Buildings Cross-Section Figure 3-5 North Buildings Cross-Section Figure 3-6 East Buildings Cross-Section Figure 3-7 Proposed Stormwater Treatment Facilities Figure 3-8 Proposed Circulation Improvements Figure 3-9 Project Phasing Figure Walnut Creek BART Station, Figure Existing Parking BART Garage, Figure Scenic Corridors and Significant Views in Walnut Creek Figure Required Building Setbacks Figure Designated Gateways Figure View Northwest from North California Boulevard at Ygnacio Valley Road Figure View North from Ygnacio Valley Road at Oakland Boulevard Figure View from the BART Platform Figure Location of Transit Village Relative to Interstate Figure Maximum Increased Cancer Risk for 70-Year Exposure at Transit Village Receptor Locations Figure Archaeologically Sensitive Areas Figure Potentially Historic Resources Figure Regional Faulting and Seismicity Figure Mapped Landslides and Slopes Greater than 15 Percent in Walnut Creek Figure Liquefaction Susceptibility Figure Threat to People from Wildland Fire Figure Watersheds in the Vicinity of the Project Site Figure Flood Prone Areas iii

8 TABLE OF CONTENTS Figure Dam Failure Inundation Hazard Area Figure General Plan 2025 Land Use Designations Figure Core Area Building Height Limits Figure Proposed Building Heights in Relation to Measure A Limits Figure Land Use/Noise Compatibility Figure Noise Measurement Locations Figure Fire Stations and Fire Service Areas in Walnut Creek Figure Parks and Special-Use Areas in Walnut Creek Figure BART Access Hierarchy Figure Site Location Figure Existing Vehicular Access Points at Project Site Figure Study Intersections Figure Existing Bus Routes Figure County Connection Route 4 Free Downtown Shuttle Figure BART Station Auto Parking Existing Capacities, Restrictions, and Fees Figure Patron Drop-off and Pick-up and Taxi Zone Parking Areas Figure Significance Criteria Classification Figure Project Site Plan Figure Pedestrian Circulation Figure Bus Circulation Figure Bicycle Circulation Figure Automobile Circulation Figure Mitigation Measure TRAFFIC-3 Reconfiguration of Pedestrian Crossing of Ygnacio Valley Road Right-In-Only Access iv

9 BART CITY OF WALNUT CREEK TRANSIT VILLAGE DRAFT EIR TABLE OF CONTENTS List of Tables Table 2-1 Summary of Impacts and Mitigation Measures Table 3-1 Project Buildout by Phase Table 4-1 Cumulative Projects Table Ambient Air Quality Standards for Criteria Pollutants Table Attainment Status of Criteria Pollutants in the San Francisco Air Basin Table Ambient Air Quality Monitoring Summary Table Regional Project-Level Criteria Air Pollutant Thresholds Table Average Daily Air Pollutant Emissions From Construction (Pounds Per Day) Table Regional Air Pollutant Emissions in Table Mitigated Construction Risk Summary Off-site Receptors Table On-Site Community Risk Summary Table Variation in Maximum Cancer Risk (per million) at the Receptor Location with the Highest Overall Cancer Risk for a 70-Year Exposure Table Maximum Computed Cancer Risk From Interstate 680 or Bus Traffic Table Maximum PM2.5 Concentrations Table On-Site Cumulative Community Risk Summary Table Groundborne Vibration Impact Criteria Table Definitions of Acoustical Terms Table Typical Sound Levels Table Reaction of People and Damage to Buildings for Continuous/Frequent Intermittent Vibration Levels Table Summary of Noise Measurements Table Vibration Source Levels for Construction Equipment Table ABAG Projections 2009 Population, Households, and Employment Forecasts for Walnut Creek v

10 TABLE OF CONTENTS Table Required Land Dedication per Unit Table Walnut Creek Public School Enrollment Trends Table Signalized Intersection Level of Service Definitions Table Unsignalized Intersection Level of Service Definitions Table Freeway Level of Service Definitions Table Walnut Creek BART Station Services Aggregate Headways Table BART Capacity Utilization at Peak Load Point Table County Connection Existing Bus Routes and Frequencies Table Existing County Connection Bus Ridership Walnut Creek BART Station Table Approved Projects Table Intersection Operations Baseline Conditions Table Ygnacio Valley Road Delay Index Summary Baseline Conditions Table Freeway Operations Baseline Conditions Table Intersection Operations Future Baseline Conditions Table Ygnacio Valley Road Delay Index Summary Future Baseline Conditions Table Freeway Operations Future Baseline Conditions Table Intersection Operation Significance Criteria Table Mode Split Summary Table Walnut Creek Transit Village Project Land Uses Trip Generation By Mode Table Intersection Operations Baseline plus Walnut Creek Transit Village Project Table Ygnacio Valley Road Delay Index Summary Baseline Conditions Scenarios Table Freeway Operations Baseline plus Walnut Creek Transit Village Project vi

11 BART CITY OF WALNUT CREEK TRANSIT VILLAGE DRAFT EIR TABLE OF CONTENTS Table Intersection Operations Future Baseline plus Walnut Creek Transit Village Project Table Ygnacio Valley Road Delay Index Summary Future Baseline Conditions Scenarios Table Freeway Operations Future Baseline plus Walnut Creek Transit Village Project Table Parking Supply Comparison Proposed versus Required Table EBMUD Demand and Supply Projections Table Walnut Creek WTP Demands (MGD) Table Wastewater Generation Table Greenhouse Gases and Their Relative Global Warming Potential Compared to CO Table Summary of Global Climate Change Risks to California Table Walnut Creek Community GHG Emissions by Sector Table Project-Related GHG Emissions Table 5-1 Comparison of Project Alternatives To the Proposed Project As Mitigated Table 5-2 Comparison of Impacts and Required Mitigation for the Project and Alternatives vii

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13 1 INTRODUCTION This Draft Environmental Impact Report (Draft EIR) has been prepared in accordance with the California Environmental Quality Act (CEQA) with the City of Walnut Creek as the lead agency. This Draft EIR assesses the potential environmental consequences of implementing the proposed Walnut Creek BART Transit Village Project (Project), and identifies mitigation measures and alternatives to the proposed Project that would avoid or reduce significant impacts. This Draft EIR is intended to inform City decisionmakers, other responsible agencies, and the general public as to the nature of the Project. A. Environmental Review Process Pursuant to State CEQA Guidelines Section 15063, the City of Walnut Creek determined that the proposed Project could result in potentially significant environmental impacts and that an EIR would be required. In compliance with Section of the California Public Resources Code, the City circulated a Notice of Preparation (NOP) of an EIR for the proposed Project to the Office of Planning and Research (OPR) State Clearinghouse and interested agencies and persons on January 20, 2009 for a 30-day review period. The NOP and scoping process solicited comments from identified responsible and trustee agencies, as well as interested parties regarding the scope of the Draft EIR. Appendix A, of this Draft EIR contains the NOP as well as the comments received by the City in response to the NOP. This Draft EIR will be available for review by the public and interested parties, agencies, and organizations for a 45-day comment period. During the comment period, the public is invited to submit written or comments on the Draft EIR and/or requested entitlements to the City of Walnut Creek Community Development Department. Written comments should be submitted to: Chip Griffin, Associate Planner City of Walnut Creek 1666 North Main Street 1-1

14 INTRODUCTION Walnut Creek, CA Fax: Following the close of the 45-day comment period, a Final Environmental Impact Report (Final EIR) will be prepared, which will respond to substantive comments received on the Draft EIR that are related to the potential environmental consequences of the Project. The Final EIR will be available for public review before being considered for certification as adequate by the Walnut Creek City Council. After the City Council certifies the Final EIR, it will also consider the Project itself, which it may approve, deny, or approve with conditions. The City Council may require the mitigation measures specified in this Draft EIR as conditions of Project approval, and it may also require other feasible mitigation measures. Alternately, the City Council may find that the mitigation measures are outside the jurisdiction of the City to implement, or that there are no feasible mitigation measures for a given significant impact. In the latter case, the City Council may nonetheless determine that the Project is necessary or desirable due to specific overriding considerations, including economic factors, and may approve the Project despite an unavoidable, significant impact. B. Report Organization This Draft EIR is organized into the following chapters: Chapter 1: Introduction. Provides an overview describing the Draft EIR document. Chapter 2: Report Summary. Summarizes environmental consequences that would result from implementation of the Project, describes recommended mitigation measures, and indicates the level of significance of environmental impacts before and after mitigation. 1-2

15 INTRODUCTION Chapter 3: Project Description. Describes the Project in detail, including the Project site location and characteristics, Project objectives, and the structural and technical elements of the proposed action. Chapter 4: Environmental Evaluation. Provides a description of the existing environmental setting, an analysis of the potential direct, indirect, and cumulative environmental impacts of the proposed Project, and presents recommended mitigation measures to reduce their significance. Chapter 5: Alternatives to the Proposed Project. Considers three alternatives to the proposed Project: a Reduced Density Alternative, under which a total of 367 dwelling units would be constructed on-site but outside of the Diesel Particulate Matter (DMP) exceedance area; an Equal Density / Reconfigured Site Plan Alternative, under which the proposed site plan would be modified to accommodate a total of 596 dwelling units on-site but outside of the Diesel Particulate Matter (DMP) exceedance area; and a No Project Alternative involving continued operation of existing on-site uses. Chapter 6: CEQA-Required Assessment Conclusions. Discusses growth inducement, unavoidable significant effects, and significant irreversible changes as a result of the Project. Chapter 7: Report Preparation. Identifies the preparers of the Draft EIR. Chapter 8: References. Identifies organizations and Persons Consulted. 1-3

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17 2 REPORT SUMMARY This summary presents an overview of the proposed Project and conclusions of the analysis contained in Chapters 4.0 through 4.13 of this Draft EIR. This summary also identifies areas of controversy and alternatives to the Project. For a complete description of the Project, please see Chapter 3, Project Description. For a discussion of Project alternatives, please see Chapter 5 of this Draft EIR. A. Proposed Project Walnut Creek Transit Lifestyle Associates, LLC, the Project Applicant, is proposing to construct and operate a mixed-use transit-oriented development on a 16.5-acre site surrounding the Walnut Creek BART station (the Project ). The proposed Project would be predominantly residential, with some ground floor commercial, retail, flex space, and office space. The Project would also involve circulation improvements, landscaping, and construction of new parking facilities. The principal components of the Project are: Residential Component: A maximum of 596 units would be constructed in four four-story buildings (over underground parking) on the site. One pair of buildings would be located in the northern portion of the site, and a second pair would be situated in the eastern portion of the site. The north buildings would contain a maximum of 358 residential units and the east buildings would contain a maximum of 238 units. Residential units would be provided on all floors; however, the ground floors would contain a mixture of residential, commercial, retail, and flex space. Commercial/Retail Component: A total of approximately 22,000 gross square feet (gsf) of retail and commercial space would be provided in newly constructed buildings on the site. This space would consist of approximately 13,300 gsf of general commercial/retail space catering to people living and working on the site and in the surrounding neighborhood, as well as roughly 8,650 gsf of transit serving retail, catering to BART and CCCTA bus riders. Retail/commercial space would be located primarily on the ground floors of the proposed buildings and oriented toward areas with the most pedestrian, bicycle, and vehicular traffic. 2-1

18 REPORT SUMMARY Flex Space: The Project also includes approximately 16,700 gsf of flex space, adaptable to residential, residential amenity space, live/work space, or commercial/retail use in consideration of prevailing market conditions. This flex space would be equivalent to about 17 dwelling units and would be located on the ground floors of the four buildings proposed for construction on-site. Office Space: A new office facility would be constructed in the southern portion of the Project site to be leased and occupied by BART Police. The new facility would be incorporated into the new parking structure. The facility would provide approximately 4,000 square feet of office space that would be leased to BART Police. Parking Facilities: The Project would provide parking facilities for the use of transit riders, residents, and patrons of the commercial and flex spaces. In order to maintain parking capacity, the existing BART parking structure would be preserved and restriped and a new parking garage would be built on the western section of the site. The Project will replace existing BART surface parking spaces at a 1:1 ratio and increase the parking count by up to an additional 100 parking spaces. This would be accommodated through a combination of restriping the existing garage and the construction of additional spaces in the new garage to provide a total of up to 948 BART parking spaces in addition to those available in the existing BART parking garage. The new structure would have five levels, including one below-grade level and four above-grade levels. Parking for BART Police vehicles would be included among the spaces in the proposed structure. Parking for residents and commercial patrons would be provided in below grade and ground level parking lots incorporated into the four mixed-use buildings6. A total of 854 spaces would be provided, with 511 spaces incorporated into the north buildings and 343 spaces in the east buildings. Additionally, the Project proposes replacement of existing motorcycle parking at a 1:1 ratio. CCCTA Bus Terminal: The existing 11-bay CCCTA bus terminal would be relocated and expanded as part of the proposed Project. A new 15-bay 2-2

19 REPORT SUMMARY bus terminal would be constructed on the west side of the BART tracks, adjacent to the existing BART parking structure. The new bus terminal would be incorporated into the new parking structure, located at ground level. Vehicle Circulation Improvements: The Project would involve six key improvements for vehicle circulation on and adjacent to the site. These would be private improvements in the public right of way. The intersection of Pringle and Riviera Avenues would be reconstructed and a three way stop control would be installed. An existing driveway on North California would be reconstructed to connect with the existing driveway which runs north of the existing BART parking structure, allowing vehicle, bicycle, and pedestrian access through the site between North California Boulevard and Riviera Avenue. Three existing on street parking spaces would be removed from the west side of North California Boulevard to allow for construction of the new entry drive. North California Boulevard would be widened along its west side to construct a service loading zone for the proposed east buildings and potential new bus stop for the Walnut Creek trolley. No street parking would be removed to accommodate the new loading zone. The existing mid-block entry/exit driveway from Ygnacio Valley Road would be reconfigured to allow vehicle access to the proposed new parking structure. The reconfiguration would result in clearer separation of vehicle, bicycle, and pedestrian traffic flows for improved safety. Vehicle access to the underground garages below the proposed North and East Buildings would be provided. A new access drive would be constructed on North California Boulevard to accommodate vehicle access to the new underground parking facility below the east buildings. No street parking would be removed to accommodate this new access drive. Along the south side of Pringle Avenue, all existing parallel parking spaces would be removed and a new access drive would be 2-3

20 REPORT SUMMARY constructed to provide vehicle access to the new underground parking facility below the north buildings and to accommodate bicycles. Pedestrian Circulation and Amenities: The proposed Project would involve improvements to facilitate pedestrian circulation on the site and to and from surrounding locations. Two pedestrian paseos would be constructed to provide direct access to BART fare gates from Pringle Avenue and Northern California Boulevard. The paseos would be landscaped and contain a variety of paving textures and public art. A new signalized, ADA-compliant pedestrian crossing would also be installed at mid-block on North California Boulevard. Additionally, pedestrian access would be provided under the BART line on either side of the station, where vehicle traffic would generally be limited to emergency and service vehicles. Bicycle Circulation and Amenities: The existing bike lanes on both sides of North California Boulevard would be maintained, and the proposed Project would provide direct access to the BART station for bicyclists traveling south on North California Boulevard by way of a new rightin/right-out access point for bicyclists and autos. Additionally, the new signalized pedestrian crossing at mid-block on North California Boulevard would give cyclists safe access to the existing northbound bicycle lane from the Project site. Bicycle access to the station would also be provided from Ygnacio Valley Road, as well as from Pringle Avenue and Riviera Avenue, via the driveway north of the existing BART structure. Bike parking at the existing BART station would be enhanced to include a publicly accessible bicycle pavilion. The facility would be located adjacent to the BART platform and east of the fare gates, as either a free standing structure or integrated into the ground floor of the proposed East Buildings. Bike parking for the residents of the new units would be incorporated inside the respective buildings at either the ground floor or in the garage in designated bike parking areas. 2-4

21 REPORT SUMMARY B. Areas of Controversy The following is a discussion of issues that are likely to be of particular concern to agencies and interested members of the public during the environmental review process. This list does not necessarily identify all areas of concern, but attempts to capture those that are likely to generate greatest interest based on the input received during the scoping process. Traffic and Transportation. Development of the Project would result in new vehicle trips to and from the Project site, which has the potential to impact operations at intersections and along roadways segments in the surrounding area. As there are several other projects proposed or approved concurrently in the Core Area of Walnut Creek, cumulative traffic impacts that could result from development of the Project in combination with other reasonably foreseeable projects in the vicinity are of particular concern. The Project would also substantially alter circulation within the site and could potentially result in vehicle/pedestrian/bicycle conflicts. Air Quality. Construction activities associated with the Project have the potential to temporarily impact local air quality through the generation of fugitive dust and toxic air contaminants from construction vehicles and equipment. As the San Francisco Bay Area Air Basin is in nonattainment for O3, PM2.5, and PM10, and as there are several other projects proposed or approved concurrently in the Core Area of Walnut Creek, cumulative air quality impacts that could result from construction of the Project in combination with other reasonably foreseeable projects in the vicinity are of particular concern. The proposed Project would place sensitive receptors near I-680, a busy freeway with trucks that emit diesel particulate matter (DPM), long term exposure to which could result in increased risk of cancer. Noise. The Project site is located within an urbanized area where ambient noise levels are generally high due to traffic volumes and BART train operations. The Project would locate residences near the BART tracks and I-680. Additionally, noise from construction activities could result in 2-5

22 REPORT SUMMARY ambient average noise levels above the standards established in General Plan 2025 during the construction phase of the Project. Aesthetics. Development of the Project has the potential to adversely affect views along two scenic corridors established in General Plan 2025 in order to protect views of Mount Diablo and surrounding open space. Development of the Project would also substantially alter the visual character of the Project site, which is located at the intersection of Ygnacio Valley Road and North California Boulevard, an important gateway to the community. C. Significant Impacts and Mitigation Measures Under CEQA, a significant impact on the environment is defined as a substantial, or potentially substantial, adverse change in any of the physical conditions within the area affected by the project, including land, air, water, minerals, flora, fauna, ambient noise, and objects of historic and aesthetic significance. The proposed Project has the potential to generate significant environmental impacts in a number of areas; however, as shown in Table 2-1, all significant impacts would be reduced to a less-than-significant level if the mitigation measures recommended in this Draft EIR are implemented. Table 2-1 is organized to correspond with the environmental issues discussed in chapters 4.1 through 4.13, and identifies environmental impacts; significance prior to mitigation; mitigation measures; and significance after mitigation. For a complete description of potential impacts and suggested mitigation measures, please refer to the specific discussions in Chapters 4.1 through CEQA allows environmental issues for which there is no likelihood of a significant impact to be scoped out during the EIR scoping process, and not analyzed further in the EIR. As described in detail in Chapter 4.0 of this Draft EIR, the Project would have no significant impact on agricultural, mineral, or biological resources due to existing conditions in the Project site and surrounding areas. These issues have therefore not been analyzed further in this Draft EIR. 2-6

23 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES Significance Significance Before With Significant Impact Mitigation Mitigation Measures Mitigation AESTHETICS The Project would not result in any significant project-specific or cumulative impacts to aesthetics and therefore no mitigation measures are required. AIR QUALITY AQ-1: Project demolition and construction activities could gener- S AQ-1: The Project shall comply with the following BAAQMD LTS ate fugitive dust, specifically PM10. Though these emissions would Best Management Practices (BMPs) for reducing construction emis- not exceed BAAQMD standards, BAAQMD nonetheless recom- sions: mends, and the City requires, that all proposed projects implement 1. All exposed surfaces (e.g. parking areas, staging areas, soil piles, BAAQMD s Basic Control Measures for fugitive dust control dur- graded areas, and unpaved access roads) shall be watered two ing construction. times per day. 2. All haul trucks transporting soil, sand, or other loose material off-site shall be covered. 3. All visible mud or dirt track-out onto adjacent public roads shall be removed using wet power vacuum street sweepers at least once per day. The use of dry power sweeping is prohibited. 4. All vehicle speeds on unpaved roads shall be limited to 15 mph. 5. All roadways, driveways, and sidewalks to be paved shall be completed as soon as possible. Building pads shall be laid as soon as possible after grading unless seeding or soil binders are used. PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-7

24 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significant Impact Significance Before Mitigation Mitigation Measures AQ-1 continued 6. Idling times shall be minimized either by shutting equipment off when not in use or reducing the maximum idling time to 5 minutes (as required by the California airborne toxics control measure Title 13, Section 2485 of California Code of Regulations [CCR]). Clear signage shall be provided for construction workers at all access points. 7. All construction equipment shall be maintained and properly tuned in accordance with manufacturer s specifications. All equipment shall be checked by a certified mechanic and determined to be running in proper condition prior to operation. 8. Construction equipment shall not be staged adjacent to existing residences or sensitive receptors. 9. A publicly visible sign with the telephone number and person to contact at the Lead Agency regarding dust complaints will be posted. This person shall respond and take corrective action within 48 hours. The Air District s phone number shall also be visible to ensure compliance with applicable regulations. AQ-2: Use of heavy off-road and on-road construction equipment S AQ-2: The construction contractor shall implement the following would produce substantial emissions of TACs and PM2.5, which measures to reduce construction exhaust emissions during grading would exceed the BAAQMD off-site community risk and hazards and construction activities: threshold of significance. This would be a significant impact. The construction contractors shall use Level 2 Diesel Particulate Filters for construction equipment over 75 horsepower. A list of construction equipment by type and model year shall be maintained by the construction contractor on-site. Significance With Mitigation LTS PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-8

25 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significance Significance Before With Significant Impact Mitigation Mitigation Measures Mitigation AQ-2 continued The construction contractor shall ensure that all construction equipment is properly serviced and maintained to the manufacturer s standards to reduce operational emissions. The construction contractor shall limit nonessential idling of construction equipment to no more than five consecutive minutes. AQ-3: Operation of the Project would expose sensitive receptors S AQ-3: For those residential units where the cancer risk is predicted LTS residing in Phase II of the Project to unhealthy levels of TACs, to be in excess of the threshold, the applicant shall install Minimum particularly DPM, emitted by vehicle traffic on Interstate 680 adja- Efficiency Reporting Value (MERV) filters with a rating sufficient cent to the Project site. This would result in a significant impact. to achieve compliance with the BAAQMD threshold for each unit or install a filtration system that achieves an equivalent percent reduction in particulate concentrations. MERV 11 filters have a particle size removal efficiency that results in a 65 percent to 80 percent reduction of particulates in the 1.0 to 3.0 micron range and will be required for those units where the cancer risk is the greatest. Assuming installation of a MERV-11 filter system that removes at least 65 percent of the DPM/PM2.5 inside of residential units and an outdoor exposure of 3 hours per day for residents, the excess cancer risk for the maximum exposed individual (MEI) would be reduced from 18 in a million to 7.8 in a million. Prior to final Project approval, a filtration system shall be specified that will reduce DPM/PM2.5 concentrations at each residential unit where the cancer risk is predicted to be significant (i.e. above 10 in a million). Because the air quality study was intended as a worst case analysis PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-9

26 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significant Impact Significance Before Mitigation Mitigation Measures AQ-3 continued and a more refined analysis that includes more detailed Project design, such as unit locations, ventilation, and more accurate move-in date, may find that a different number units will require such filtration (or different filtration), this measure may be refined if, prior issuance of building permits, the Project Applicant conducts a subsequent refined evaluation of air quality and air filtration system specifications and demonstrates that an alternative air filtration system or its application to a different number of residential units would continue to ensure that health risks remain below the thresholds set forth by the BAAQMD or the City with regard to exposure to toxic air contaminants. To ensure long-term maintenance and replacement of the MERV filters in the residential units, the owner/property manager shall maintain and replace the filters in accordance with the manufacturer s recommendations. The rental representative shall also provide notification to all affected tenants of the potential health risk from Interstate 680 and shall inform renters of increased exposure to DPM from Interstate 680 when the windows are open. Significance With Mitigation CULTURAL RESOURCES The Project would not result in any significant project-specific or cumulative impacts to cultural resources and therefore no mitigation measures are required. GEOLOGY AND SOILS The Project would not result in any significant project-specific or cumulative impacts to geology hazards and soils, and therefore no mitigation measures are required. PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-10

27 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significance Significance Before With Significant Impact Mitigation Mitigation Measures Mitigation HAZARDS AND HAZARDOUS MATERIALS The Project would not result in any significant project-specific or cumulative impacts to hazards or hazardous materials, and therefore no mitigation measures are required. HYDROLOGY AND WATER QUALITY The Project would not result in any significant project-specific or cumulative impacts to hydrology and water quality, and therefore no mitigation measures are required. LAND USE AND PLANNING The Project would not result in any significant project-specific or cumulative impacts to land use and planning and therefore no mitigation measures are required. NOISE NOISE-1: The Project proposes residential units in an area where S NOISE-1: Sound-rated building construction shall be used to LTS noise levels are considered conditionally acceptable, resulting in a achieve acceptable indoor noise levels (45 dba Ldn, 50 dba Lmax in potentially significant impact. The site design locates primary out- bedrooms, and 55 dba Lmax in other rooms) in residential units door activity areas in shielded courtyards. Exterior noise levels throughout the site. Building sound insulation treatments include, would be 65 dba Ldn or less, assuming the shielding provided by but are not limited to sound retardant windows and doors, resilient the structure surrounding the primary outdoor use areas, meeting wall constructions, heavy siding and roofing materials (e.g. stucco, the normally acceptable noise level standard. The following mit- Hardi-plank), ventilation silencers, and gasketing. All residential igation measure reduces interior noise to an acceptable level. units in the Project shall require mechanical ventilation or a sound attenuating zee duct to allow for air circulation while windows are closed for noise control. The specification of these treatments PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-11

28 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significant Impact Significance Before Mitigation Mitigation Measures NOISE-1 continued shall be developed during the architectural design of the buildings and shall be summarized in a report. This report shall be submitted and approved by the building department prior to issuance of building permits. NOISE-2: Noise generated by construction activities is anticipated S NOISE-2: Develop a construction mitigation plan in close coordination to exceed ambient average noise level limits by more than 5 dba with adjacent noise-sensitive land uses so that construction Leq for a period exceeding one year. activities can be scheduled to minimize noise disturbance. The construction mitigation plan shall consider the following available controls to reduce construction noise levels as low as practical. The following measures, when applicable, shall be included to reduce noise from construction activities to below the impact threshold level of 5 dba Leq above the ambient: Significance With Mitigation LTS Equip all internal combustion engine-driven equipment with mufflers, which are in good condition and appropriate for the equipment. Construction equipment must be well maintained. Utilize quiet models of air compressors and other stationary noise sources where technology exists. Quiet equipment typical generate noise levels 5 dba lower than that of comparable equipment. Locate stationary noise-generating equipment as far as feasible from sensitive receptors (e.g., residences, BART platform, sensitive personnel areas) when these receptors adjoin or are within 200 feet of a construction Project area. PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-12

29 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significance Significance Before With Significant Impact Mitigation Mitigation Measures Mitigation NOISE-2 continued Prohibit unnecessary idling of internal combustion engine. Construct fences using plywood or material bearing the same sound attenuating effectiveness as plywood between portions of the construction sites and sensitive receptors, such as residences and public areas, including the plaza and the BART Station itself. Route construction related traffic along major roadways and as far as feasible from sensitive receptors. Ensure that construction activities (including the loading and unloading of materials and truck movements) are conducted in accordance with the hours restrictions set forth in Municipal Code section (f) and do not exceed 5 dba Leq above ambient noise levels. Residences or noise-sensitive land uses adjacent to the construction site should be notified of the construction schedule in writing. Designate a construction liaison that would be responsible for responding to any local complaints about construction noise. The liaison would determine the cause of the noise complaints (e.g. starting too early, bad muffler, etc.) and institute reasonable measures to correct the problem. Conspicuously post a telephone number for the liaison at the construction site. PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-13

30 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significance Before Mitigation Significance With Mitigation Significant Impact Mitigation Measures POPULATION, HOUSING, AND EMPLOYMENT The Project would not result in any significant project-specific or cumulative impacts to population, housing, or employment and therefore no mitigation measures are required. PUBLIC SERVICES AND RECREATION The Project would not result in any significant project-specific or cumulative impacts to the provision of school services and therefore no mitigation measures are required. TRANSPORTATION AND PARKING TRAFFIC-1: The addition of Project traffic at the Parkside Drive/Buena Vista Avenue intersection would cause the intersection to operate at LOS F, resulting in a potentially significant impact during the PM peak hour under Future Baseline plus Project Conditions. S TRAFFIC-1: As the intersection would eventually operate at unacceptable conditions, and meet the criteria of the CA MUTCD Peak Hour Traffic Volume Signal Warrant with and without the addition of the proposed Project, the CA MUTCD criteria suggest the intersection be signalized. However, both the Walnut Creek traffic signalization ordinance and the CA MUTCD also provide that engineering judgment must be brought to bear on the decision to implement and timing of implementation of a traffic signal. The CA MUTCD offers a list of alternatives to traffic control signals for consideration, including (but not limited to) the following: Relocating the stop line(s) and making other changes to improve the sight distance at the intersection; Adding one or more lanes on a minor-street approach to reduce the number of vehicles per lane on the approach; Revising the geometrics at the intersection to channelize vehicular movements and reduce the time required for a vehicle to complete a movement, which could also assist pedestrians; and LTS PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-14

31 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significance Significance Before With Significant Impact Mitigation Mitigation Measures Mitigation TRAFFIC-1 continued Installing a roundabout. Due to the anticipated cumulative volume increase at this location, the implementation of any of these alternatives would continue to result in unacceptable operations. The City Traffic Engineer has considered all factors, and has likewise considered the fact that modeling done for this EIR suggests no other form of traffic control device will mitigate this impact as effectively as the installation of a traffic signal. In light of this, the City Traffic Engineer concurs with the suggested installation of a traffic signal at this location, when the warrant is satisfied. Since the impact of the Project itself will not immediately necessitate the installation of a traffic signal, but rather, will make a cumulatively considerable contribution to the future need for a signal at this intersection, it is appropriate to mitigate this future impact through the following measures: Project Applicant shall pay the Traffic Impact Fee assessed against the Project. Project Applicant shall likewise fund biennial monitoring (i.e., every two years) of the performance of this intersection until issuance of building permits for Phase III of Project construction. The City will program the signalization of this intersection into the list of projects eligible for construction funding through the use of Traffic Impact Fees. PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-15

32 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significance Significance Before With Significant Impact Mitigation Mitigation Measures Mitigation TRAFFIC-2: The addition of Project traffic at the Parkside S TRAFFIC-2: As the intersection would eventually operate at unac- LTS Drive/Hillside Avenue intersection would result in a potentially ceptable conditions, and meet the criteria of the CA MUTCD Peak significant impact during the PM peak hour under Future Baseline Hour Traffic Volume Signal Warrant with and without the addi- plus Project Conditions. tion of the proposed Project, the CA MUTCD criteria suggest the intersection be signalized. However, both the Walnut Creek traffic signalization ordinance and the CA MUTCD also provide that engineering judgment must be brought to bear on the decision to implement and timing of implementation of a traffic signal. The CA MUTCD offers a list of alternatives to traffic control signals for consideration, including (but not limited to) the following: Relocating the stop line(s) and making other changes to improve the sight distance at the intersection; Adding one or more lanes on a minor-street approach to reduce the number of vehicles per lane on the approach; Revising the geometrics at the intersection to channelize vehicular movements and reduce the time required for a vehicle to complete a movement, which could also assist pedestrians; and Installing a roundabout. Due to the anticipated cumulative volume increase at this location, the implementation of any of these alternatives would continue to result in unacceptable operations. The City Traffic Engineer has considered all factors, and has likewise considered the fact that PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-16

33 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significant Impact Significance Before Mitigation Mitigation Measures TRAFFIC-2 continued modeling done for this EIR suggests no other form of traffic control device will mitigate this impact as effectively as the installation of a traffic signal. In light of this, the City Traffic Engineer concurs with the suggested installation of a traffic signal at this location, when the warrant is satisfied. Significance With Mitigation Since the impact of the Project itself will not immediately necessitate the installation of a traffic signal, but rather, will make a cumulatively considerable contribution to the future need for a signal at this intersection, it is appropriate to mitigate this future impact through the following measures: Project Applicant shall pay the Traffic Impact Fee assessed against the Project. Project Applicant shall likewise fund biennial monitoring (i.e., every two years) of the performance of this intersection until issuance of building permits for Phase III of Project Construction. The City will program the signalization of this intersection into the list of projects eligible for construction funding through the use of Traffic Impact Fees. PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-17

34 REPORT SUMMARY TABLE 2-1 SUMMARY OF IMPACTS AND MITIGATION MEASURES (CONTINUED) Significance Significance Before With Significant Impact Mitigation Mitigation Measures Mitigation TRAFFIC-3: Safety is a concern for the on-site pedestrian route S TRAFFIC-3: The channelized right-in-only site access from Yg- LTS between Hillside Avenue and the BART station entrance. The nacio Valley Road is recommended to be reconfigured to reduce the existing unsignalized crossing of the channelized right-in-only site risk to pedestrians. The recommended configuration is shown in access is considered less than ideal, as motorists exiting Ygnacio Figure , which would position the lane splitting off the right- Valley Road may approach the proposed crosswalk at excessive in-only site access to enter the proposed new parking structure speed. The greater width of the crossing as proposed by the Project slightly farther downstream, allowing the crossing to be limited to would increase pedestrian exposure to this hazard, and the more the width of one lane, as well as allowing it to be oriented more acute angle would make pedestrians and motorists less visible to perpendicular to oncoming traffic, as in its present configuration. each other. The mitigation would also include the installation of yield-topedestrians signage. UTILITIES AND SERVICE SYSTEMS The Project would not result in any significant impacts to solid waste disposal services; therefore, no mitigation measures are necessary. GREENHOUSE GAS EMISSIONS GHG-1: GHG emissions generated by the proposed Project would LTS GHG-1: Mitigation Measure AQ-2, described in Chapter 4.2 of LTS not exceed BAAQMD s per capita GHG threshold for operation- this EIR, would reduce construction equipment exhaust emissions related GHG emissions. This would be a less than significant im- during grading and construction activities and would also reduce pact. However, BAAQMD encourages implementation of construction-related GHG emissions. measures to reduce construction-related emissions to the maximum extent practicable. PS = Potentially Significant; S = Significant; LTS = Less than Significant; SU = Significant and Unavoidable 2-18

35 3 PROJECT DESCRIPTION Walnut Creek Transit Lifestyle Associates, LLC, the Project Applicant, is proposing to construct and operate a mixed-use transit-oriented development on a 16.5-acre site surrounding the Walnut Creek BART station (the Project ). This chapter provides a detailed description of the proposed Project, including the location, setting, and characteristics of the Project site, the Project objectives, the principal Project features, Project phasing and approximate construction schedule, as well as required permits and approvals. A. Project Location and Setting 1. Regional Location The Project site is located in the City of Walnut Creek, in central Contra Costa County. Walnut Creek is located approximately 23 miles east of San Francisco, at the foot of Mt. Diablo, as shown in Figure 1-1 in Chapter 1 of this EIR. Regional access to the Project site is provided by Interstate 680 (I-680), adjacent to the Project site, State Highway 24, and by Bay Area Rapid Transit District (BART) commuter train service. 2. Local Setting The Project site, owned by BART, is located at 200 Ygnacio Valley Road. The Walnut Creek BART Station is located near the center of the Project site, and its rail line bisects the site on a southwest to northeast axis, as shown in Figure 1-2 (see Chapter 1, Introduction). The site is bounded by Pringle Avenue to the north, North California Boulevard to the east, Ygnacio Valley Road to the south, and I-680 along the western edge of the site. The site occupies the prominent crossroad of North California Boulevard and Ygnacio Valley Road, a gateway to the rest of the city. Adjacent to the southwest corner of the site there is access to I-680 via Ygnacio Valley Road. Residential neighborhoods are located on the west side of the freeway. 3-1

36 PROJECT DESCRIPTION 3. Existing Site Character The 16.5-acre Project site currently serves as a public transportation hub for Walnut Creek and surrounding communities, with the Walnut Creek BART station and an eleven-bay Contra Costa County Transit Authority (CCCTA) bus terminal located near its center. The site is entirely built out and the majority of its surface area is given over to parking facilities, including a threestory BART parking structure with roof-top podium parking and four large surface parking lots. The existing BART garage provides a total of 1,241 parking spaces on four levels, including a roof-top podium level. The surface parking lots provide a total of 848 parking spaces on-site. Additionally, there are 19 BART patron drop off spaces, five taxi spaces, and 20 motorcycle parking spaces provided along the internal roadway which runs west of the BART line and south of the existing BART garage. Figure 3-1 shows an aerial view of the Project site with existing development, access points, and internal driveways. Opened in 1973, the Walnut Creek BART station is a concrete structure built on two levels. The station's ticket vending area, fare gates, and bicycle storage lockers are located at ground level, connected to two elevated train platforms by stairways, escalators, and an elevator. Central portions of the train platforms are covered by overhead canopies that provide protection from weather. A large electrical sub-station is located underneath the tracks in the northeast portion of the site. A total of 130 bicycle parking spaces are available around the station entrance, with 66 spaces on wave racks near the fare gates and 64 in secured bicycle lockers housed within the BART station. The CCCTA bus terminal is an open air structure, located to the east of the BART rail line, aligned perpendicularly to it. Buses enter the site either at the Ygnacio Valley Road entrance or from Riviera Avenue, exiting the site either through an egress point along North California Boulevard or an egress point on Pringle Avenue. Two internal roads provide access to on-site parking areas. An S-shaped road runs between Riviera Avenue and Ygnacio Valley Road 3-2

37 PROJECT DESCRIPTION Pringle Avenue Pedestrian Access Way 680 Riviera Avenue (417 Spaces) (36 Spaces) Existing BART Garage (1,241 Spaces) (82 Spaces) North California Boulevard (269 Spaces) (44 Spaces) Internal Roadways Full Access (in/out) Ygnacio Valley Road CCCTA Bus Terminal Right-in-only Access Right-out-only Access Bicycle Racks Bicycle Lockers Taxi Zone BART Patron Drop-off/ Pick Up Spaces ( # ) Existing Parking Spaces NORTH Feet Source: The Planning Center DC&E, FIGURE 3-1 AERIAL VIEW OF EXISTING DEVELOPMENT ON THE PROJECT SITE

38 PROJECT DESCRIPTION south of the existing BART parking structure, while a J-shaped road runs north of the BART garage and curves around the eastern surface parking lots with access points at Riviera Avenue, Ygnacio Valley Road, and North California Boulevard. B. Project Objectives In coordination with the Walnut Creek City Council, the Applicant has developed the following Project objectives: Enhance the role of the site as a regional transportation hub; Provide access and circulation to and through the site that works for all modes of transportation; Ensure visual and physical connections of the Project with the City of Walnut Creek; Create an attractive, mixed-use residential neighborhood with retail uses that cater to future residents, transit riders, and surrounding uses; Consistent with the transit-oriented policies in SB 375, BART s Transit Oriented Development Policy, and the City s General Plan 2025, capitalize on the proximity to BART by maximizing the residential density; Provide various features of value to residents, transit riders, and users, potentially including amenities such as programmable public plazas/urban open space, publicly accessible views of Mt. Diablo, public art, rentable meeting room/commercial space, car-share program, and shuttle service to downtown Walnut Creek. C. Project Components The Applicant proposes to redevelop existing on-site surface parking lots with a mixed-use residential and commercial complex as shown in Figure 3-2. The 3-4

39 PROJECT DESCRIPTION Proposed New Parking Structure and Bus Terminal South Building Patron Drop-Off/Pick-Up/ Taxi Loading Zone Existing BART Garage North Buildings BART Station East Buildings Source: MVE & Partners, FIGURE 3-2 PROPOSED MIXED USE TRANSIT ORIENTED DEVELOPMENT CONCEPT

40 PROJECT DESCRIPTION proposed Project would be predominantly residential, with some ground floor commercial, retail, flex space and office space. The Project would also involve circulation improvements, landscaping, and construction of new parking facilities. The principal components of the Project are described below. The proposed Project would not include upgrades or improvements to the BART station. 1. Residential Component A maximum of 596 units would be constructed in four four-story buildings (over underground parking) on the site. As shown in Figure 3-2, one pair of buildings would be located in the northern portion of the site, and a second pair would be situated in the eastern portion of the site. The north buildings would contain a maximum of 358 residential units and the east buildings would contain a maximum of 238 units. Project site plans, reproduced below as Figure 3-3, indicates residential units on all floors; however, the ground floors would contain a mixture of residential, commercial, retail, and flex space. Figures 3-4 through 3-6 show cross-sections of the south, north, and east buildings. As shown, building heights would not exceed 50 feet above ground level (not including acceptable vertical penetrations). All residential units would be rental apartments. The Project Applicant shall comply with the City s Inclusionary Housing Ordinance.. 1 The Project would contain approximately 6,670 gross square feet (gsf) of residential amenity space, providing fitness rooms and indoor common areas to residents. 1 City of Walnut Creek, Ordinance No.2095, Walnut Creek Municipal Code, Title 10, Chapter 2, Part III, Article 9 "Inclusionary Housing,

41 PROJECT DESCRIPTION PHASE I EXISTING BART PARKING STRUCTURE PHASE II PHASE III Source: MVE & Partners, FIGURE 3-3 PROPOSED SITE PLAN - GROUND LEVEL

42 PROJECT DESCRIPTION Source: MVE & Partners, FIGURE 3-4 SOUTH BUILDING CROSS SECTION

43 PROJECT DESCRIPTION Section A Section B Source: MVE & Partners, FIGURE 3-5 NORTH BUILDINGS CROSS - SECTION

44 PROJECT DESCRIPTION Section A Section B Source: MVE & Partners, FIGURE 3-6 EAST BUILDINGS CROSS - SECTION

45 PROJECT DESCRIPTION 2. Commercial/Retail Component A total of approximately 22,000 gsf of retail and commercial space would be provided in newly constructed buildings on the site. This space would consist of approximately 13,300 gsf of general commercial/retail space catering to people living and working on the site and in the surrounding neighborhood, as well as roughly 8,650 gsf of transit serving retail, catering to BART and CCCTA bus riders. As shown in Figure 3-3, retail/commercial space would be located primarily on the ground floors of the proposed buildings and oriented toward areas with the most pedestrian, bicycle, and vehicular traffic. 3. Flex Space The Project also includes approximately 16,700 gsf of flex space, adaptable to residential, residential amenity space, live/work space, or commercial/retail use in consideration of prevailing market conditions. This flex space would be equivalent to about 17 dwelling units and would be located on the ground floors of the four buildings proposed for construction on-site. 4. Parking Facilities The Project would provide parking facilities for the use of transit riders, residents, and patrons of the commercial and flex spaces. In order to maintain parking capacity, the existing BART parking structure would be preserved and restriped and a new parking garage would be built on the western section of the site. The Project would replace existing BART surface parking spaces at a 1:1 ratio and increase the parking count by up to an additional 100 parking spaces. This would be accommodated through a combination of restriping the existing garage and the construction of additional spaces in the new garage to provide a total of up to 948 BART parking spaces in addition to those available in the existing BART parking garage. The new structure would have five levels, including one below-grade level and four above-grade levels as shown in Figure 3-6. Parking for BART Police vehicles would be included among the spaces in the proposed structure. Parking for residents and commercial patrons would be provided in below grade and ground level parking lots incorporated into the four mixed-use 3-11

46 PROJECT DESCRIPTION buildings, as pictured in Figures 3-5 and 3-6. A total of 854 spaces would be provided, with 511 spaces incorporated into the north buildings and 343 spaces in the east buildings. Additionally, the Project proposes replacement of existing motorcycle parking at a 1:1 ratio. 5. CCCTA Bus Terminal The existing 11-bay CCCTA bus terminal would be relocated and expanded as part of the proposed Project. As shown in Figures 3-3 and 3-4, a new 15- bay bus terminal would be constructed on the west side of the BART tracks, adjacent to the existing BART parking structure. The new bus terminal would be incorporated into the new parking structure, located at ground level. 6. BART Police Facility A new office facility would be constructed in the southern portion of the Project site to be leased and occupied by BART Police. The new facility would be incorporated into the new parking structure, as shown in Figure 3-3. The facility would provide approximately 4,000 square feet of office space that would be leased and occupied by BART Police. 7. Relocated Patron Drop-off/Pick-up Facility and Taxi Loading Zone The existing patron drop-off/pick-up facility and taxi loading zone, currently located south of the existing BART parking structure, would be relocated to the north of that structure. The driveway north of the existing BART parking structure would be widened from approximately 25 feet to a proposed width of 40 feet to accommodate these features. The widened driveway would also provide auto and pedestrian access. 8. Stormwater Management A network of bio-retention areas and flow-thru planters connected to the City s storm sewer system would be constructed around the perimeter of the Project site, as shown in Figure 3-7. This would provide in-ground filtration of stormwater and reduce the volume of run-off flowing into the storm sewer system. Landscaping and pervious pavers would also be used throughout the 3-12

47 PROJECT DESCRIPTION NORTH Feet Pringle Avenue NOT PART OF PROJECT Proposed Parking Structure NOT PART OF PROJECT North Buildings Ygnacio Valley Road East Buildings North California Boulevard Source: MVE & Partners, FIGURE 3-7 CONCEPTUAL STORMWATER TREATMENT PLAN

48 PROJECT DESCRIPTION site to provide bio-filtration and natural drainage of runoff from the new structures. The Project would meet or exceed all provisions set forth under C.3 of the Municipal Regional Stormwater NPDES Permit. Stormwater runoff from the BART station and the existing parking structure currently flows into the City storm sewer system. The Project does not propose changes to treatment of stormwater runoff from these structures. 9. Vehicle Circulation Improvements The Project would involve six key improvements for vehicle circulation on and adjacent to the site, as shown in Figure 3-8. These would be private improvements in the public right of way. First, in order to accommodate vehicle access to the patron drop-off/pick-up facilities adjacent to the BART station, the intersection of Pringle and Riviera Avenues would be reconstructed. This would involve the installation of a three-way stop control. Second, an existing driveway on North California would be reconstructed to connect with the existing driveway which runs north of the existing BART parking structure, allowing vehicle, bicycle, and pedestrian access through the site between North California Boulevard and Riviera Avenue. Three existing on street parking spaces would be removed from the west side of North California Boulevard to allow for construction of the new entry drive. Third, North California Boulevard would be widened along its west side to construct a service loading zone for the proposed east buildings and potential new bus stop for the Walnut Creek trolley. No street parking would be removed to accommodate the new loading zone. Fourth, the existing mid-block entry/exit driveway from Ygnacio Valley Road would be reconfigured to allow vehicle access to the proposed new parking structure, as shown in Figure 3-8. The reconfiguration would result in clearer separation of vehicle, bicycle, and pedestrian traffic flows for improved safety. 3-14

49 PROJECT DESCRIPTION 1 6 Existing BART Parking Garage 7a b Full Access (in/out) Pedestrian Access Source: The Guzzardo Partnership, Pringle/Riviera Intersection Reconfigured 2. New Access Drive Constructed 3. North California Boulevard Widened for Services Loading Zone 4. Mid-Block Access Drive Reconfigured 5. New Vehicle Access to Access to Underground Parking (East Buildings) 6. New Vehicle Access to Access to Underground Parking (North Buildings) 7. Pedestrian Paseos Constructed 8. New Signalized Pedestrian Crossing Installed FIGURE 3-8 PROPOSED CIRCULATION IMPROVEMENTS

50 PROJECT DESCRIPTION Additionally, vehicle access to the underground garages below the proposed North and East Buildings would be provided as shown in Figure 3-8. A new access drive would be constructed on North California Boulevard to accommodate vehicle access to the new underground parking facility below the east buildings. No street parking would be removed to accommodate this new access drive. Finally, along the south side of Pringle Avenue, all existing parallel parking spaces would be removed and a new access drive would be constructed to provide vehicle access to the new underground parking facility below the north buildings and to accommodate bicycles. 10. Pedestrian Circulation and Amenities The proposed Project would involve improvements to facilitate pedestrian circulation on the site and to and from surrounding locations, as shown in Figure 3-8. Two pedestrian paseos would be constructed to provide direct access to BART fare gates from Pringle Avenue and Northern California Boulevard. The paseos would be landscaped and contain a variety of paving textures and public art. A new signalized, ADA-compliant pedestrian crossing would also be installed at mid-block on North California Boulevard. Additionally, pedestrian access would be provided under the BART line on either side of the station, where vehicle traffic would generally be limited to emergency and service vehicles. 11. Bicycle Circulation and Amenities The existing bike lanes on both sides of North California Boulevard would be maintained, and the proposed Project would provide direct access to the BART station for bicyclists traveling south on North California Boulevard by way of a new right-in/right-out access point for bicyclists and autos. Additionally, the new signalized pedestrian crossing at mid-block on North California Boulevard would give cyclists safe access to the existing northbound bicycle lane from the Project site. Bicycle access to the station would also be provided from Ygnacio Valley Road, as well as from Pringle Avenue and Riviera Avenue, via the driveway north of the existing BART structure. Bike parking at the existing BART station would be enhanced to include a publicly accessible bicycle pavilion. The facility would be located adjacent to the 3-16

51 PROJECT DESCRIPTION BART platform and east of the fare gates, as either a free standing structure or integrated into the ground floor of the proposed East Buildings. Bike parking for the residents of the new units would be incorporated inside the respective buildings at either the ground floor or in the garage in designated bike parking areas. 12. Tree Removal and Replacement There are currently 69 trees on the Project site, including three Valley Oaks classified as highly protected trees under the City of Walnut Creek Tree Protection Ordinance (Walnut Creek Municipal Code, Title 3, Chapter 8). The proposed Project would preserve these three Valley Oak trees on-site. The other 66 unprotected trees would be removed and replaced with a variety of climate appropriate species. 13. Water Supply The Project site is located within the East Bay Municipal Utility District (EBMUD) service area and EBMUD would supply water for the Project. Existing infrastructure would be preserved in place and extensions would be installed to supply water to the Project site. Extensions would not encroach on undisturbed areas. 14. Sanitary Sewer Service The Central Contra Costa Sanitary District (CCCSD) provides wastewater collection and treatment service for Walnut Creek. Sanitary wastewater generated on the Project site would be treated by CCCSD at a wastewater treatment plant located near Martinez. Existing infrastructure would be preserved in place and extensions would be installed to channel effluent from the Project site. Extensions would not encroach on undisturbed areas. 15. Other Utilities (Gas, Electricity, Communications, and Cable) Gas and electricity would be supplied to the Project site by Pacific Gas & Electric (PG&E). Telephone service would be provided by AT&T and other providers. Cable television service would be available from a number of providers, including Comcast. Additionally, a photovoltaic cell (PVC) array is 3-17

52 PROJECT DESCRIPTION proposed for installation on the roof of the new parking structure. The PVC panels would use anti-reflective glass which absorb sunlight and have approximately half the reflectance of standard residential glass. The PVC panels would also have limited rotational angles in order to avoid the potential for reflecting the sun s rays upon any ground plane position or surrounding roadways. Electricity produced by the panels would serve the systems in the proposed parking structure. Any extra electricity generated would go back to the local electrical distribution grid. D. General Plan and Zoning Amendments Required Project implementation would require the following amendments to the City of Walnut Creek General Plan 2025 and Zoning Ordinance. 1. Amendments to the Walnut Creek General Plan The Project would require a General Plan amendment to allow for construction and operation of the proposed mixed use residential buildings on the eastern portion of the site. East of the BART tracks, the Project site is currently designated Public/Semi-Public. The applicant has requested that the General Plan land use designation for this portion of the site be changed to Mixed Use Residential Emphasis. Additionally, the Core Area Height Limit for the portion of the site east of the BART tracks would need to be amended to allow for construction of buildings up to 50 feet tall. West of the BART tracks, the current Mixed Use Residential Emphasis land use designation would remain unchanged, as would the current Core Area Building Height of 50 feet. 2. Amendments to the Zoning Ordinance Project implementation would also require the re-zoning of the site, currently zoned Community Facility (CF) in its entirety. The applicant has requested a re-zoning of the whole site to Planned Development (PD). Additionally, a 3-18

53 PROJECT DESCRIPTION Zoning Ordinance Building Height Map amendment would be required to increase the building height limit to 50 feet from its current limit of 35 feet. 2 E. Development Agreement In order to provide vested development rights for the Project and memorialize certain public benefits to be offered by Project Applicant, the City, the Project Applicant, and BART are considering entering into a Development Agreement. F. Tentative Map The subdivision map for the Property currently consists of a historic residential subdivision that pre-dates the BART station. The Project includes a tentative map that would remove these outdated parcels and reconfigure the parcelization to make it consistent with the proposed Project. The tentative map is proposed to include four parcels. The Project would be developed on three of the parcels, with the existing BART station and parking garage on the fourth parcel. G. Project Phasing The Project is proposed to be constructed in three phases starting in The anticipated construction schedule includes some overlap of phases and completion of construction activities is expected in Table 3-1 illustrates the Project s phasing concept, indicating the number of residential units to be built and the number of parking spaces to be provided, as well as the approximate gross square footages of commercial, retail, office, and flex space to be 2 Building height limits in the zoning code allow for extensions up to 12 feet above the roof line for, among other features, non-occupiable mechanical equipment structures on the roof. 3-19

54 PROJECT DESCRIPTION TABLE 3-1 PROJECT BUILDOUT BY PHASE Phase I (15 Months) Phase II (31 Months) Phase III (25 Months) Total (71 Months) Office Space 4,000 sf 0 0 4,000 sf Commercial/Retail Space 0 6,500 sf 6,800 sf 13,300 sf Transit Serving Retail Space 0 2,200 sf 6,450 sf 8,650 sf Flex Space 0 3,320 sf 13,385 sf 16,705 sf Residential Units Relocated and New BART Parking Spaces New Residential/Retail Parking Spaces Source: MVE & Partners, constructed. The activities and components associated with each phase are described below, together with the anticipated duration. 1. Phase I Phase I of Project construction would take place primarily in the southern portion of the site. This phase would involve the construction of the new parking structure and CCCTA Bus terminal as well as the new BART Police facility. The existing surface parking lot, patron drop-off and pick-up facility, and taxi zone currently in the southern portion of the site would be demolished to make way for new construction. The relocated patron drop-off / pick-up facility and taxi zone would also be built during this phase, prior to demolition of the southern parking lot. To accommodate them, the driveway and sidewalks immediately north of the existing parking structure would be widened as described above. Clearing and demolition activities during this phase of the Project would require off-hauling approximately 6,600 cubic yards of material, while excavation activities would result in a net volume of approximately 29,000 cubic yards of material removed from the site. The 3-20

55 PROJECT DESCRIPTION Phase I construction area is shown in Figure 3-9. Phase I would be completed in approximately 15 months, with staging for this phase within the boundaries of this Phase. During this phase of Project construction, the existing BART parking structure would be re-striped using compact parking space dimensions so as to provide up to 63 permanent additional parking spaces for BART patrons. 2. Phase II Phase II of Project construction would take place in the northern portion of the site, as shown in Figure 3-9. This phase would see the construction of the north buildings, the reconstruction of the Pringle Avenue and Riviera Avenue intersection, and the addition of the new entry drive on North California Boulevard. Landscaping and installation of the stormwater management features associated with the north buildings would also take place during this phase of construction. As the new BART parking structure, which replaces all of the existing surface BART parking, would be operational by the start of Phase II, a surface parking lot on the eastern portion of the site would be available for use as a staging area. The existing surface parking lot in the northern portion of the site, west of the BART tracks, would be demolished to make way for new construction, as would the 82-space surface lot immediately to the east of the BART station. Additionally, 36 surface parking spaces under the BART alignment would also be removed to make way for the new access drive on North California Boulevard. During this phase of the Project, clearing and demolition would require offhauling approximately 12,100 cubic yards of material, and excavation for the underground parking garages would result in a net volume of 74,000 cubic yards of material removed from the site. Phase II would be completed in approximately 31 months. 3. Phase III Phase III of Project construction would involve the construction of the east buildings, the widening of North California Boulevard, the addition of the new mid-block pedestrian crossing, and the reconfiguration of the entry/exit 3-21

56 PROJECT DESCRIPTION Existing BART Parking Garage PHASE 1 PHASE 2 Pringle Avenue BART Station PHASE 3 PHASE 2 STAGING Ygnacio Valley Road North California Boulevard NORTH Source: The Guzzardo Partnership, FIGURE 3-9 PROJECT PHASING

57 PROJECT DESCRIPTION driveway from Ygnacio Valley Road described above. Landscaping, pedestrian and bicycle circulation improvements, and installation of stormwater management features for the eastern portion of the Project would also take place during this phase of construction, which is anticipated to last 25 months. The Phase III construction area is shown in Figure 3-9. The existing surface parking lots in the eastern portion of the site would be demolished to make way for new construction during this phase. In total, Phase III clearing and demolition would require off-hauling approximately 12,200 cubic yards of material, while excavation for underground parking garages would result in a net volume of 48,200 cubic yards of material removed from the Project site. H. Required Permits and Approvals 1. City of Walnut Creek Permits and Approvals The City permits and approvals listed below would be required for Project implementation. The Project may also require approvals by other Responsible Agencies at the State and local levels, including BART, the Regional Water Quality Control Board (RWQCB), and the Bay Area Air Quality Management District (BAAQMD). 3 These agencies may rely on this EIR in determining CEQA compliance for their discretionary actions. Amendments to the Walnut Creek General Plan Amendment of the Zoning Ordinance Building Height Map Rezoning of the Project site Development Agreement (optional) Tentative Map Approval Design Review Approval (at each development phase) Building Permits Demolition, Grading, and Excavation Permits Tree Removal Permit 3 Under CEQA, the term Responsible Agency includes all public agencies, other than the Lead Agency, which have discretionary approval authority over aspects of the Project for which the Lead Agency has prepared an EIR. 3-23

58 PROJECT DESCRIPTION 2. BART Permits and Approvals Approval by the BART Board of Directors 3-24

59 4.0 ENVIRONMENTAL EVALUATION This section of the Draft EIR is made up of 13 chapters which evaluate the direct, indirect, and cumulative environmental impacts of the proposed Walnut Creek BART Transit Village Project by examining the following environmental issues: Aesthetics Air Quality Cultural Resources Geology and Soils Hazards and Hazardous Materials Hydrology and Water Quality Land Use and Planning Noise Population, Housing, and Employment Public Services and Recreation Transportation and Traffic Utilities and Service Systems Greenhouse Gas Emissions A. Environmental Issues Scoped Out As described in Chapter 2 of this Draft EIR, CEQA allows environmental issues for which there is no likelihood of significant impact to be "scoped out" during the EIR scoping process, and not analyzed further in the EIR. Given that the Project site is currently almost entirely built out and that it is located in the highly urbanized Core Area of Walnut Creek, the Project would have no impact on agricultural or mineral resources and these issues have therefore not been analyzed further in this Draft EIR. Additionally, due to the extent of development on the Project site and in its vicinity, the intensity of human activity in the Core Area, and the fact that natural biological communities have by and large been replaced with nonnative and ornamental plantings, the Project site has low to poor wildlife habitat value. The City's General Plan 2025 EIR determined that most of the special-status animal species known or suspected to occur in Walnut Creek 4-1

60 ENVIRONMENTAL EVALUATION are bird species that forage in the remaining undeveloped areas of the city and that essential breeding habitat is absent from the Walnut Creek sphere of influence. Further, there are no wetlands and no riparian habitat on or adjacent to the Project site that could be adversely affected by development of the proposed Project. Therefore, given existing conditions on the Project site and in the surrounding area, development of the proposed Project would have no significant impact on biological resources and this issue has also not been analyzed further in this Draft EIR. Potential conflicts with policies and regulations pertaining to the protection of trees are addressed in Chapter 4.7 of this Draft EIR. B. Chapter Organization Each chapter in this section is organized into the following subsections: Regulatory Framework provides an overview of federal, State, regional and local laws and regulations relevant to each environmental issue. Existing Conditions describes current conditions with regard to the environmental issue, and in some cases future conditions without the Project, providing a baseline against which the impacts of the Project can be compared. Standards of Significance explains the quantitative or qualitative standard or conditions used to compare the existing setting with and without the Project to determine whether the impact is significant. These standards are based primarily on the CEQA Guidelines, and may reflect established health standards, ecological tolerance standards, public service capacity standards, and guidelines established by agencies or experts. Impact Discussion describes potential Project impacts and cumulative impacts and why each impact was found to be significant or less than significant. Cumulative Impacts Analysis analyzes impacts that the proposed Project may have when considered in addition to other past, present and reasonably foreseeable projects. (See further discussion below.) 4-2

61 ENVIRONMENTAL EVALUATION Summary of Impacts and Mitigation Measures numbers and lists identified impacts, and presents measures that would mitigate each impact. In each case, the significance following mitigation is also explained. C. Cumulative Impact Analysis A cumulative impact consists of an impact created as a result of the combination of the project evaluated in the EIR, together with other reasonably foreseeable projects causing related impacts. Section of the CEQA Guidelines requires an EIR to discuss cumulative impacts of a project when the project's incremental effect is cumulatively considerable. Where the incremental effect of a project is not cumulatively considerable, a Lead Agency need not consider that effect significant, but must briefly describe its basis for concluding that the incremental effect is not cumulatively considerable. Where the cumulative impact caused by the project's incremental effect and the effects of other projects is not significant, the EIR must briefly indicate why the cumulative impact is not significant. The cumulative discussions in Chapters 4.1 through 4.13 explain the geographic scope of the area affected by each cumulative effect (e.g. immediate project vicinity, city, county, watershed, or air basin). The geographic area considered for each cumulative impact depends upon the impact that is being analyzed. For example, in assessing aesthetic impacts, only development within the vicinity of the Project would contribute to a cumulative visual effect because the Project site is only visible within the vicinity of the site. In assessing macro-scale air quality impacts, on the other hand, all development within the air basin contributes to regional emissions of criteria pollutants, and basin-wide projections of emissions is the best tool for determining the cumulative effect. The CEQA Guidelines provide two approaches to analyzing cumulative impacts. The first is the list approach, which requires a listing of past, present 4-3

62 ENVIRONMENTAL EVALUATION and reasonably anticipated future projects producing related or cumulative impacts. The second is the projections-based approach wherein the relevant growth projections contained in an adopted general plan or related planning document designed to evaluate regional or area-wide conditions are summarized. A reasonable combination of the two approaches may also be used. The cumulative impact analysis in this Draft EIR relies on a projections-based approach supplemented by an understanding of past, present, and reasonably foreseeable future projects in the vicinity of the Walnut Creek BART Transit Village Project site that, when considered with the effects of the Project, may result in cumulative effects. The cumulative analysis discussions contained in Chapters 4.1 through 4.13 include a discussion of the growth projections and references to specific projects as relevant to the impact analysis. Specific projects referenced include approved or pending projects in the vicinity of the Transit Village Project site that are anticipated to be constructed and occupied by Specific projects referenced are shown in Table

63 ENVIRONMENTAL EVALUATION TABLE 4-1 CUMULATIVE PROJECTS Size No. Project Name Location Commercial Square feet Residential Units Residential 1 Pleasant Creek Homes 1935 Barkley Avenue 10 2 Paragon Apartments 141 North Civic Drive North Main Apartments (former WC Motor Lodge) 1960 North Main Street The Arroyo Apartments 1250 Arroyo Way Walden Park Commons El Oak Road 55 6 E lan (formerly Riviera Homes) 1605 Riviera Avenue 38 7 Villagewalk Condos Lacassie Avenue 11 8 Bonanza Heritage Condominiums 1874 & 1882 Bonanza St 1826 Sharpe Ave Ygnacio 235 Ygnacio Valley Road Walker-Sierra Townhomes 1241 Walker Avenue 4 11 Overlook Homes 2245 Overlook Drive 8 12 Cole Terrace Subdivision/Condominiums 1756 Cole Ave Parkview Condos 1665 Carmel Drive 7 14 Homestead Terrace Homes 1279 Homestead Ave 8 15 Holcomb Court Condos 15 Holcomb Court 2 16 Overlook Town Homes 2725 Overlook Drive 6 17 Lincoln Avenue Triplex 1229 Lincoln Avenue 2 18 Almond Lofts 1960 and 1972 Almond Avenue 1600 Oakland Boulevard 9 19 Howard Oaks Subdivision 2361 and 2373 Walnut Boulevard 3 Commercial / Office 20 Nordstrom Remodel / Expansion 1200 Broadway Plaza 18,

64 ENVIRONMENTAL EVALUATION TABLE 4-1 CUMULATIVE PROJECTS (CONTINUED) Size Commercial No. Project Name Location Square feet 21 Neiman Marcus 1196 Broadway Plaza 50, Dirito Brothers Volkswagen Walnut Creek 2020 North Main Street 29, John Muir Medical Center Master Plan Amendment (Phase 4) 1601 Ygnacio Valley Road 443, Hour Fitness/Chick-Fil-A 2800 N. Main Street 47,343 Residential Units 25 Co-op Site Retail Development 1510 Geary Road 35, Shadelands Gateway Ygnacio Valley Road and Oak Grove 246, Safeway Remodel 600 South Broadway 25, Broadway Plaza Long Range Master Plan 300,000 Mixed Use 29 The Village 1500 Newell Avenue 38, Walnut Creek BART Transit Village 200 Ygnacio Valley 22, Walnut Creek BART Transit Village (Office) 4,000 Walnut Creek BART Transit Village (Flex space) 16,705 Total 1,275,538 1,388 Source: City of Walnut Creek,

65 4.1 AESTHETICS This chapter discusses the existing aesthetic character of the Project site and its surroundings, evaluating the potential impacts to aesthetics associated with development of the Project. The following evaluation assesses visual character, scenic vistas, scenic highways, light, and glare. A. Regulatory Framework This section summarizes key State and city regulations and programs related to aesthetics at the Project site. There are no federal regulations pertaining to aesthetics that apply to the Project. 1. State Regulations a. California Scenic Highway Program The California Scenic Highway Program, maintained by the California Department of Transportation (Caltrans), protects scenic State highway corridors from changes which would diminish the aesthetic value of lands adjacent to the highways. A 14-mile segment of Interstate 680 (I-680) from the Alameda County line north to State Route 24 (SR-24) is an officially designated Scenic Highway under the Program, providing views of Mount Diablo. 1 The segment of I-680 which runs to the west of the Project site is not a designated Scenic Highway. b. Solar Rights Act The 1978 California Solar Rights Act establishes the legal right to a solar easement, defines which solar energy systems are covered by its provisions, and limits local governments from adopting ordinances that would unreasonably restrict the use of solar energy systems. 2 Reasonable restrictions, includ- 1 California Department of Transportation California Scenic Highways Program, accessed on December 7, Database of State Incentives for Renewables and Efficiency (DSIRE), accessed on May 30,

66 AESTHETICS ing those made based on aesthetic considerations, include those that do not significantly increase the cost of the system or significantly decrease its efficiency. In general, restrictions are deemed reasonable under California law so long as they do not result in cost increases exceeding $2,000 or performance decreases of more than 20 percent. 3 The Solar Rights Act also provides that Cities shall approve applications for solar energy systems through nondiscretionary permits and that review shall be limited to whether the system meets all health and safety requirements. 2. Local Policies and Regulations a. Walnut Creek General Plan 2025 General Plan 2025 provides guidance to help new development achieve the quality desired by the community, regulating development intensity, building height, building setback, and building stepbacks. Pursuant to Measure A, the Building Height Freeze Initiative, General Plan 2025 establishes maximum height limits for buildings in the Core Area of the city, including the Project site. General Plan 2025 also identifies scenic views, scenic corridors, landmarks, and gateways to be preserved and protected. The Built Environment chapter of General Plan 2025 includes the following goals, policies, and actions pertaining to urban form and visual character: GOAL 13. Maintain and enhance high quality building design and urban design. Policy Maintain urban design and architectural standards for evaluating the scale, appearance, and compatibility of new development proposals. Action During the City s review processes, confirm that the project design will be compatible with adjacent uses. 3 California Civil Code Sections 714 et seq

67 AESTHETICS Action Consistently apply the City s Design Review Guidelines and periodically examine and revise as needed. Action Review and maintain the building setback map for the Core Area, and amend the zoning ordinance as necessary. Policy Regulate building placement and upper-floor stepbacks along important streets in the Core Area. Action Establish building setbacks along specifically designated streets. Action Use policies to encourage developers of new buildings to include public plazas, courtyards, significant landscaping, or other public amenities that are visible and accessible from the street. Action Develop a comprehensive plan for siting and developing public and publicly accessible spaces and plazas in the Core Area. Action Use policies to encourage new and existing commercial development to incorporate accessible roof gardens, ground-level public plazas, public courtyards and passageways, landscaping, public art, and other desired public amenities beyond those specified during the normal City review process. Policy Coordinate the building heights allowed under the general plan, zoning ordinance, and Measure A. Action Allow increases in height, up to the Measure A height limits, for developments that provide exceptional public amenities such as accessible roof gardens, ground-level public plazas, creek orientations, public courtyards and passageways, land

68 AESTHETICS scaping, public art, and other desired public amenities beyond those specified during the normal City review process. GOAL 16. Maintain and enhance Walnut Creek s identity and sense of place. GOAL 17. Enhance the entrances to the City. Policy At all major entrance points to the city develop welcoming gateways that emphasize the unique qualities of Walnut Creek. Action At each gateway, install similarly themed gateway designs. Action Prepare design guidelines for areas and properties adjacent to the gateways to the city. GOAL 18. Preserve and enhance the visual amenity provided by the open space, hills, and creeks. Policy Preserve and enhance the urban connections to scenic views that are so important to residents and visitors. Action Identify and map specific public vistas and views. Action Develop guidelines to preserve and enhance notable public view corridors. Action Preserve and enhance the offsite visual appearance of open space lands, particularly the views from other vantage points in the city. GOAL 19. Enhance the urban design quality of the Core Area and its subareas. Policy Use specific plans and precise plans for subareas within the Core Area

69 AESTHETICS Policy Improve directional signage for pedestrians and vehicles in the Core Area. Action Design and implement a comprehensive Core Area directional sign program that shows shuttle stops; parking garage locations, capacities, and availability; orients residents and visitors; and shows optimal routes for getting to key cultural, shopping, and civic destinations in the city. GOAL 26. Develop a comprehensive, integrated plan to preserve the natural environment in the built environment. Policy Preserve and add to the City s tree canopy. b. Zoning Ordinance Contained in Title 10, Chapter 2 of the Walnut Creek Municipal Code, the City's Zoning Ordinance identifies specific zoning districts within the city and describes the development standards that apply to each district. The Project site is currently zoned Community Facility (CF). In the CF district, minimum lot area, lot width, frontage, depth, setback, landscaping, and parking requirements are determined in the approval of a Conditional Use Permit. The Applicant has requested that the entire property be re-zoned to Planned Development so as to allow the specific uses and site configuration proposed. c. Design Review Title 10, Chapter 2, Section of the Walnut Creek Municipal Code establishes a Design Review Commission to conduct design review of development, including architectural standards and site planning controls. The Design Review process is intended to promote quality architectural design, site planning, and landscape development. The process is aimed at improving and augmenting other development controls included in the Walnut Creek Planning and Building Ordinances. The City's 1996 Design Review Guidelines, prepared by the Planning Division and the Public Information Office under direct review by the Walnut 4.1-5

70 AESTHETICS Creek Design Review Commission, contains guidelines intended to assist applicants in understanding the standards of design that will be used to evaluate and review projects proposed for Design Review approval. The Design Review Guidelines address site relationships, landscape design, off-street parking design, fencing and screening, architecture, signage, and special environmental constraints. The following standards, among others from the Design Review Guidelines, would apply to the proposed Project: Chapter 2 I. General Architectural Guidelines 1. Architectural design shall be compatible with the developing character of the neighboring area. 2. Diversity of architectural design shall be encouraged within the City. 3. Multiple buildings on the same site shall be designed to create a cohesive visual relationship between the buildings. 4. Exterior building design and detail on all elevations shall be coordinated with regard to color, types of materials, number of materials, architectural form, and detailing to achieve harmony and continuity of design. 5. Commercial and residential buildings shall be sited to provide functional, livable outdoor spaces, and public spaces which enhance the use of the building and, to the greatest extent possible, the neighboring buildings. 7. Exterior materials shall be durable and of high quality. Highly reflective materials in general are discouraged. 9. The visibility of roof-top equipment should be minimized by grouping all plumbing vents, ducts, and roof-top mechanical equipment away from the public view. II.C. Multiple-Family Residential 1. New multiple-family residential development shall respect the scale and character of the adjacent residential neighborhood through attention to 4.1-6

71 AESTHETICS views, building scale and orientation, proximity to adjacent uses, location of driveways, noise, lighting and landscape. 2. Building facades should be articulated by using color, arrangement, or change in materials to emphasize the facade elements. 5. All trash enclosures shall be constructed of sturdy, opaque materials (with trash receptacles screened from view) which are in harmony with the architecture and materials of the main buildings. IV. City Gateways 1. The appearance and prominence of city gateways shall be improved through the use of appropriate signage, landscaping, setbacks, and building design to signal a transition into the City's Core Area. 2. Sites located at prominent gateway locations shall be required to provide additional landscaping treatment and may be required to provide special design amenities, such as public art. 3. City designed projects should take advantage of gateway locations to create a sense of entry by the use of improvements such as landscaping, building corner setbacks, special lighting, public art, or other design amenities. 4. Rear service yards, product storage areas, and parking lots adjacent to highways shall be totally screened to improve the appearance of sites at the city Gateways, scenic corridors, and from the highways. 5. Buildings shall be designed with a continuous architectural finish on all sides of the structure (see Architecture Guidelines) when they are visible and/or prominent from a number of street and highway of vantage points. The Project Applicant has prepared Project-specific Design Review Guidelines (the Transit Village Design Guidelines ) that further refine the Citywide Design Review Guidelines within the context of this site

72 AESTHETICS d. Public Art Master Plan The Public Art Master Plan provides guidelines for public art in Walnut Creek and is intended to encourage the inclusion of public art in development projects. The master plan identifies public art zones throughout the city, discusses the roles of the Design Review Commission and Art Commission, identifies criteria and processes to be used in the selection of artwork, and recommends funding sources. The master plan envisions artworks such as fountains, large-scale sculpture, or landscape elements integrated into plaza areas, building exteriors, or streetscapes in the Core Area, where the Project site is located. To implement this master plan, the City has adopted a Public Art Ordinance, Title 10, Chapter 10 of the Walnut Creek Municipal Code, which requires payment of a public art fee or installation of public art on-site, for development projects. B. Existing Conditions This section describes the existing visual character of the Project site and its vicinity, the scenic resources present in the surrounding area, and the light, glare, and shadow conditions on the Project site and immediately adjacent properties. 1. Visual Character a. Project Site The dominant visual features of the Project site in its existing condition are the elevated BART tracks that bisect the site and the station building. Figure shows a view of the station building and elevated tracks today. On either side of the elevated tracks are covered platforms with roofs 47 feet above ground level at their highest point. Constructed in , the station building is a grey concrete structure with red colored metallic roofing and porticos. The station building is located under the elevated tracks, connecting the BART platforms to ground level. Pedestrian access to the station building is provided via concrete sidewalks, and the floor of station building is covered with terra cotta tiles

73 AESTHETICS Another important visual feature of the Project site is the existing four-level BART parking garage, which includes a roof-top podium, located immediately west of the station building between the BART tracks and I-680. Pictured in Figure 4.1-2, the existing BART garage is a red brick structure with large sections of the facade open to the air, providing site lines to and from the upper parking levels. The highest point of the parking garage (55 feet above ground level) is the tower at the southeast corner of the building which houses a stairwell and elevators connecting upper parking levels with the ground. Between the BART garage and the station building there is a pedestrian corridor made of red brick paving stones, which is also used as an emergency vehicle corridor. At either end of the corridor, bollards prevent entry of vehicles, except emergency vehicles, ensuring pedestrian safety. The remainder of the Project site is built out with an 11-bay Central Contra Costa Transit Authority (CCCTA) bus terminal and four surface parking lots for BART patrons. The bus terminal extends perpendicularly out from the eastern entrance to the BART station with a red metallic portico similar in design to the porticos of the station building. A landscaped berm is located along the southern edge of the Project site between the parking lot and the street level sidewalks along Ygnacio Valley Road. The berm partially screens the parking lot. Elsewhere, the perimeter of the Project site is landscaped, and the asphalt surface parking lots contain some small landscaped islands and ornamental trees. Pedestrian connections to the site are provided via concrete steps leading up to the CCCTA bus terminal from the intersection of Ygnacio Valley Road and North California Boulevard and by way of a footbridge and steps up from the intersection of Pringle Avenue and North California Boulevard. b. Surrounding Area The Project site is located in the Core Area of Walnut Creek, a highly urbanized sector of the city that includes Downtown Walnut Creek and the highrise office buildings of the Golden Triangle area located to the north of the BART station. As described in Chapter 3 of this Draft EIR, an elevated segment of I-680 runs along the western perimeter of the Project site, and to the 4.1-9

74 AESTHETICS Figure Walnut Creek BART Station, 2011 Figure Existing Parking BART Garage,

75 AESTHETICS north and northeast there are two clusters of high-rise buildings dating from the mid-1980s. 4 The cluster of buildings directly to the north is composed of six main towers rising as high as ten stories. The design of these buildings features stepbacks on the upper floors, creating a terraced effect. Concrete and mirrored glass are the predominant building materials, although marble and steel are also used on the building surfaces. A smaller cluster of four office buildings ranging in height from 2 to 10 stories lies across North California Boulevard, to the east of the Project site. These buildings reflect a variety of styles, but maintain an overall theme of grey or neutral colors, expressed in exposed concrete, stucco, and metal trim. A large sunken plaza is located at the northeast corner of the intersection of North California Boulevard and Ygnacio Valley Road, and comprises the open space amenity for this cluster of buildings. A commercial area defined primarily by various auto dealerships and a big-box retail store lies southeast of the Project site. Ygnacio Valley Road separates the Project site from a residential area containing residential structures and small-scale professional office buildings. The residential buildings include three bungalow style single-family homes of varying ages and architectural styles. The multi-family residential and office buildings are two- and three-story structures with wood shingle siding and sloped roofs. This area contains numerous mature trees between the buildings and along the street frontage. Some of these trees have grown to heights of 30 feet or more. Further along Ygnacio Valley Road, to the west of Oakland Boulevard, there is a four-story, terraced office building with distinctive red-brown tiles and prominent windows. The setback area in front of the building is landscaped and planted with ornamental trees. The building stepbacks also contain plantings. 4 City of Walnut Creek: History, history/default.asp, accessed on September 22,

76 AESTHETICS 2. Scenic Resources a. Scenic Corridors and Views General Plan 2025 establishes scenic corridors and significant views that are integral to the city's identity and sense of place. As shown in Figure 4.1-3, significant views include urban views, panoramic views, and views of Mount Diablo. Scenic corridors are important roadways in the city, generally affording views of Mount Diablo or surrounding open space. Ygnacio Valley Road, which runs along the southern perimeter of the Project site, is designated a scenic corridor, as is the segment of the elevated BART tracks between Highway 24 and Pleasant Hill/Contra Costa Centre BART Station, which passes through the site. There is also a significant view of Mount Diablo from a point northwest of the Project site on Buena Vista Avenue. In order to protect views from along the Ygnacio Valley Road scenic corridor, General Plan 2025 and the Walnut Creek Municipal Code establish major setbacks of between 20 and 30 feet for buildings fronting portions of North California Boulevard and North Civic Drive, as shown in Figure b. Gateways General Plan 2025 identifies gateways to the community, including landmarks, nodes, or views that define an arrival point in Walnut Creek. Gateways promote local identity and strengthen Walnut Creek's sense of place. The intersection of Ygnacio Valley Road and North California Boulevard at the southeastern edge of the Project site is identified as a vehicular gateway, as shown in Figure Located at the confluence of these two important roadways and easily visible from I-680, the Project site serves as a symbolic entry point into the city and provides an introduction to Walnut Creek as it is viewed from a moving vehicle. c. Scenic Highways As described above, a segment of I-680 ending at SR-24 is designated a Scenic Highway under the CalTrans Scenic Highway Program. This segment is located less than 1 mile south of the Project site. However, the segment of I- 680 which runs immediately to the west of the Project site is not a designated California Scenic Highway

77 AESTHETICS NORTH Mile Source: Walnut Creek General Plan 2025, FIGURE SCENIC CORRIDORS AND SIGNIFICANT VIEWS IN WALNUT CREEK

78 I-680 Chapter 4, Built Environment CITY OF WALNUT CREEK AESTHETICS I-680 Buena Vista Ave Civic Dr Ygnacio Valley Rd Lafayette Walnut Blvd Hwy 24 Olympic Blvd Building Setbacks Minor - 0' to 10' (2' average) Moderate - 10' to 20' (15' average) Major - 20' to 30' (25' average) Highways Major Roads City Limit Planning Area Boundary Alamo NORTH Miles Source: Walnut Creek General Plan 2025, Miles Base Map Data: January 16, 2004 Figure 11. Building Setbacks FIGURE REQUIRED BUILDING SETBACKS 4-26 Walnut Creek General Plan 2025 April 4, 2006

79 AESTHETICS NORTH Mile Source: Walnut Creek General Plan 2025, FIGURE DESIGNATED GATEWAYS

80 AESTHETICS 3. Light and Glare Light pollution refers to all forms of unwanted light in the night sky around and above us, including glare, light trespass, sky glow, and over-lighting. Excessive light and glare can also be visually disruptive to humans and nocturnal animal species, and often reflects an unnecessarily high level of energy consumption. Light pollution has the potential to become an issue of increasing concern as new development contributes additional outdoor lighting installed for safety and other reasons. Existing sources of nighttime light in the vicinity of the Project site include those common to urban areas, such as street lights, parking lot lights, building lighting, vehicle headlamps, and interior lighting visible through windows. Sources of light on the Project site itself include lighting in the BART garage, the station building, and on the elevated platforms, as well as light standards installed in the surface parking lots and the CCCTA bus terminal area. The existing light standards installed in the surface parking lots are approximately 20 feet tall and provide extensive illumination throughout the Project site. The BART station operates over 20 hours a day. The first train on the northbound platform is scheduled for 4:59 a.m.; its last departure is 1:03 a.m. The westbound platform schedule is similar with its first train departing at 4:20 a.m. and the last one at 12:17 a.m. For this reason, station lighting is maintained during nighttime hours, except for a period of approximately four hours when the station is closed, in accordance with BART safety standards for its trains and passengers. Lighting in the parking garage and parking lots remain on continually during nighttime hours. CCCTA buses operate between 5:30 a.m. and 9:30 p.m. Monday through Saturday, with limited Sunday service. Nighttime lighting at the bus terminal is maintained for the terminal so as to ensure the safety of passengers and vehicles in accordance with CCCTA standards. The principal source of glare on the Project site is light reflecting off the windshields of cars parked in the surface lots around the BART station during daytime hours. The metallic trim on the station building, porticos, and bus

81 AESTHETICS terminal is painted and treated so as to prevent glare. Off-site sources of glare include windows in the office buildings to the north and northeast, as well as light reflecting off the windshields of vehicles on surrounding roadways and I-680. C. Standards of Significance The proposed Project would result in a significant aesthetic impact if it would: 1. Substantially degrade the existing visual character or quality of the site and its surroundings. 2. Have a substantial adverse effect on a scenic vista. 3. Substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic buildings within a State scenic highway. 4. Create a new source of substantial light or glare which would adversely affect day or nighttime views in the area. D. Impact Discussion 1. Substantially degrade the existing visual character or quality of the site and its surroundings. As described in Chapter 3 of this EIR, the proposed Project would involve the redevelopment of four surface parking lots around the Walnut Creek BART station and the construction of four mixed-use residential buildings and a new parking structure containing a BART Police facility. Two pedestrian paseos would provide direct access to the BART fare gates from Pringle Avenue and North California Boulevard. Benches and seating elements would be provided for pedestrians in the paseos, and distinctive paving materials and public art installations would enhance the pedestrian realm. Where the paseos intersect with on-site driveways, bollards would be provided for pedestrian safety, and throughout the site pedestrian scale lighting and light

82 AESTHETICS ribbons would increase safety and improve wayfinding. At the corner of Ygnacio Valley Road and North California Boulevard, identified in General Plan 2025 as a gateway to the city, a grand staircase, and fountain feature are proposed. The conceptual landscaping plan for the site includes a rain garden, planters, and ornamental trees. Figure shows an existing view of the Project site from its southeastern corner at the intersection of Ygnacio Valley Road and North California Boulevard contrasted with a visual simulation of the site at buildout of the Project. Development of the Project would alter the viewshed such that the grey concrete walls of the BART station and I-680 flyover would no longer be visible from this vantage point. In their place, the viewshed would contain the proposed East Buildings and a pedestrian paseo leading to the BART fare gates. Figure shows an existing view of the principal vehicular entry point onto the Project site from Ygnacio Valley Road and Oakland Boulevard, together with a visual simulation of a view from the same vantage point at development of the Project. As shown, from this location the current viewshed contains the existing CCCTA bus terminal and landscape elements on the site, as well as office buildings on the east side of North California Boulevard. At buildout, this viewshed would contain the East Buildings and the proposed replacement parking structure, as well as new landscaping features and architectural elements. As demonstrated in Figures and 4.1-7, construction of these and other elements of the proposed Project would add visual interest to the site. The Project is subject to the City s planning process, which allows Project applicants to seek modifications to City regulations. In this regard, the Project Applicant seeks certain amendments to City regulations governing aesthetic issues such as building height, setback, and floor area ratio, as discussed in detail in Chapter 4.7 of this EIR. The Project s conformance to the amended regulations would ensure that the visual character and quality of the Project site is consistent with community standards. Additionally, as part of the

83 AESTHETICS EXISTING VIEW VIEW WITH PROPOSED PROJECT (SIMULATION) Source: MVE & Partners, Inc., FIGURE VIEW NORTHWEST FROM NORTH CALIFORNIA BOULEVARD AT YGNACIO VALLEY ROAD

84 AESTHETICS EXISTING VIEW VIEW WITH PROPOSED PROJECT (SIMULATION) Source: MVE & Partners, Inc., FIGURE VIEW FROM YGNACIO VALLEY ROAD AT OAKLAND BOULEVARD

85 AESTHETICS design review process, the Project is subject to review and approval by the Design Review Commission, which evaluates proposed projects for conformance to the City s Design Guidelines. The Design Review Commission may also approve the proposed Transit Village Design Guidelines which are being prepared through a number of City staff and developer-led community workshops to address the architectural elements of the Project as well as its landscape framework, public open spaces, pedestrian paseos, and adjacent streets and sidewalks. 5 Implementation of the Transit Village Design Guidelines and review and approval by the Design Review Commission would ensure that the Project realizes General Plan Built Environment Goal 13 to maintain and enhance high-quality building design and urban design. The Project, thus, would not result in a substantial degradation of the visual character or quality of the site. Therefore, a less-than-significant impact would result. 2. Substantial adverse effect on a scenic vista. As described above and shown in Figure 4.1-3, General Plan 2025 identifies three scenic vistas in the vicinity of the Project site: views eastward along Ygnacio Valley Road; views from and along the elevated BART tracks; and views of Mount Diablo from a point northwest of the Project site on Buena Vista Avenue. Development of the Project would result in a significant impact if it would substantially and adversely affect any of these scenic vistas. General Plan 2025 includes provisions to protect views eastward along Ygnacio Valley Road, including the requirement for building setbacks shown in Figure Along the eastern boundary of the Project site, major setbacks of 20 to 30 feet are required along a segment of North California Boulevard extending north from Ygnacio Valley Road, and on both sides of Ygnacio Valley Road eastward from I-680 moderate setbacks of 10 to 20 feet are required. Project Applicant seeks to reclassify these setbacks from major to moderate along North California Boulevard in through a General Plan amendment proposed by the Project. Therefore, compliance with these regu- 5 City of Walnut Creek website, April 18, Walnut Creek BART Transit Village Design Guidelines (DRAFT), depts/cd/planning/bart_tod.asp, accessed on May 31,

86 AESTHETICS lations governing building setbacks would ensure that views along the Ygnacio Valley Road scenic corridor are not adversely affected from buildout of the Project. General Plan 2025 designates the BART alignment as a scenic corridor as it passes through the city, and as such, identifies views of open space and hills from and along the BART tracks as scenic resources. As shown in Figure 4.1-8, Mount Diablo is visible from the elevated platforms of the Walnut Creek BART station. Construction of the proposed East Buildings would alter the existing view, framing the peak of Mount Diablo between the two proposed buildings. While construction of the proposed East Buildings would partially obstruct views of the foothills of Mount Diablo, as shown in Figure 4.1-8, by framing the view of Mount Diablo, design of the Project would highlight the peak for disembarking BART passengers and patrons waiting on the platforms. Unobstructed views of Mount Diablo and surrounding open space from all other portions of the designated scenic corridor along the BART alignment would remain unchanged with development of the Project. Additionally, design of the proposed Project, including the East Buildings and the pedestrian paseo linking the entrance to the BART station and the intersection of Ygnacio Valley Road and North California Boulevard would be subject to design review for the purpose of improving and augmenting development controls included in the Walnut Creek Planning and Building Ordinances. Specifically, Chapter 1.I.A of the Design Review Guidelines requires that significant view corridors be incorporated into the new development, 6 and the Transit Village Design Guidelines include the following design recommendations: Use landscape to reinforce the visual axis to Mount Diablo without blocking views from above or below. To emphasize this vista, provide a single row of deciduous trees with an open form and upright canopy. 6 City of Walnut Creek, Design Review Guidelines, page

87 AESTHETICS EXISTING VIEW VIEW WITH PROPOSED PROJECT (SIMULATION) Source: MVE & Partners, Inc., FIGURE VIEW FROM THE BART PLATFORM

88 AESTHETICS Develop a linear landscape feature that spans the length of the paseo and reinforces the Mount Diablo vista. Such a feature should include detailed paving, seating, and planting. Provide an informal gateway where the paseo originates at BART Plaza. Tie this element conceptually to the experience of the train arrival. For example, a fog fountain that emits fog when trains arrive or disembark. This element should not block views to Mount Diablo. 7 Therefore, compliance with the Design Review Guidelines and the Transit Village Design Guidelines, which must conform to General Plan 2025, would ensure that impacts to views from the designated Scenic Corridor along the BART alignment would be less than significant. The Project site is within the viewshed of Mount Diablo as seen from the Buena Vista Avenue viewpoint identified in General Plan 2025; however, buildout of the Project would not adversely affect protected views from that vantage point. The Buena Vista Avenue viewpoint is located at a higher topographic elevation than the Project site, and compliance with Measure A building height limit incorporated into the General Plan and Zoning Ordinance would ensure that the proposed structures would not obstruct views of Mount Diablo as seen from Buena Vista. Overall, development of the proposed Project would result in a less-thansignificant impact on scenic vistas in Walnut Creek. 3. Substantially damage scenic resources, including, but not limited to, trees, rock outcroppings, and historic buildings, located within a state scenic highway. As described above, although the segment of I-680 that runs immediately to the west of the Project site is not a designated California Scenic Highway, less 7 City of Walnut Creek website, April 18, 2012 Walnut Creek BART Transit Village Design Guidelines (DRAFT), depts/cd/planning/bart_tod.asp, accessed on May 31,

89 AESTHETICS than 1 mile to the south of the site, I-680 is designated as a Scenic Highway as it meets SR-24 in order to preserve views of Mount Diablo. This State Scenic Highway designation is reflected in General Plan 2025, which identifies the view of Mount Diablo from I-680 at SR-24 as a scenic resource, as shown in Figure However, given that the Project site is located 0.7 miles to the north of this view corridor and does not enter the viewshed of Mount Diablo from the stretch of I-680 which is a designated Scenic Highway, buildout of the Project would not adversely affect views of Mount Diablo from points along this designated Scenic Highway segment. As such, there would be no impact with respect to substantially degraded views from a Scenic Highway. 4. Create a new source of substantial light or glare which would adversely affect day or nighttime views in the area. a. Light With buildout of the Project, existing sources of nighttime light associated with the BART station, the elevated tracks, and the parking garage would remain on-site. New sources of light added with buildout would include exterior lighting on the proposed buildings, in the paseos and open spaces, and inside of the new parking garage and the relocated CCCTA bus terminal. The existing approximately 20-foot tall light standards illuminating the surface lots would be removed as the proposed buildings and other Project features are constructed in their place. As a result, buildout of the Project would result in a change in illumination intensity and lighting patterns, but not an increase in intensity as compared to existing conditions on the Project site. The proposed Transit Village Design Guidelines developed by City staff and the Project Applicant for the Project indicate that site lighting would be designed so as to maintain uniform light levels along streets and in plaza areas as required to conform with City standards. The City s Design Review Guidelines, to which Project Applicant will also conform, require exterior lighting of the building and site be designed so that light is not directed off the site and mounting height of fixtures in smaller parking lots or service areas does not exceed 16 feet. According to the Transit Village Design Guidelines, up lighting would be minimized in order to reduce dark sky pollution, and LED wall

90 AESTHETICS sconces and light ribbons would be installed for wayfinding on-site. In general, light levels on the Project site would provide adequate illumination for visibility but would be controlled to prevent light from spilling into on-site residential buildings. Lights in areas of pedestrian circulation around the BART station and residential buildings would be on a control circuit to reduce the amount of light after hours. Project light design would be subject to design review and evaluated to ensure compliance with the proposed Transit Village Design Guidelines. As such, potential light pollution resulting from development of the Project would be minimized to the maximum extent practicable and associated impacts would be less than significant. b. Glare With buildout of the proposed Project, the existing on-site BART surface parking lots would be redeveloped and vehicle parking would be relocated to new parking structures. While there would be roof-top parking on the podium level of the new parking structure, overall the principal existing source of glare, light reflecting off vehicle windshields, would be reduced with development of the proposed Project. Windows in the proposed buildings would be a new potential source of glare added to the Project site; however, pursuant to the Design Guidelines proposed for the Project, the use of highly reflective materials is discouraged 8 and design review for the Project would ensure that glare from the proposed development is minimized to the maximum extent practicable. The Project applicant is considering installing photovoltaic cells (PVCs) on the roof of the proposed BART parking structure. glare from light reflecting off the PVCs upon any ground plane position or surrounding roadways, including I-680, Ygnacio Valley Road, and North California Boulevard would 8 This provision is proposed to be carried over from the City s existing Design Review Guidelines, adopted July

91 AESTHETICS be reduced to the maximum extent practicable. Overall, light and glare impacts from development of the proposed Project would be less-than-significant. E. Cumulative Impacts This section analyzes potential cumulative impacts to aesthetics that could occur from a combination of the proposed Project with other reasonably foreseeable projects in the surrounding area. The geographic scope of this analysis is taken as the Core Area of Walnut Creek. A cumulative impact would be considered significant if, taken together with past, present and reasonably foreseeable projects in the Core Area, it would result in a substantial adverse effect on a designated scenic vista, a degradation of the view from a scenic highway, exposure of people on- or off-site to substantial light or glare, or if it would result in a substantial degradation of the visual quality or character of Walnut Creek's Core Area. As described above, General Plan 2025 identifies Scenic Corridors and Significant Views in Walnut Creek, as well as landmarks and gateways important to the city's character and sense of place. General Plan 2025 and the Walnut Creek Municipal Code contain provisions to protect these scenic resources from substantial adverse effects, including building height limits for the Core Area, setback requirements for buildings along Ygnacio Valley Road and adjacent streets, applicable development standards from the Zoning Ordinance, and other architectural standards and site planning controls implemented through the design review process. Continued implementation of these existing regulations would ensure that cumulative impacts to designated scenic resources and visual quality in Walnut Creek would be less than significant. A 14-mile segment of I-680 east of SR-24 is a designated California Scenic Highway and recognized in General Plan 2025 as a Scenic Corridor. Development in the Core Area would also be subject to the same existing regulations for building height, setbacks, development intensity, and other architectural standards and site planning controls described above. Continued im

92 AESTHETICS plementation of these existing regulations would ensure that cumulative impacts to view from the scenic highway segment would be less than significant. Potential light and glare impacts from development of cumulative projects in the Core Area would be addressed through design review. Development in the Core Area would be subject to design review as established in the Municipal Code, and the Design Review Commission would evaluate potential light and glare impacts against the evaluation criteria contained in the Design Review Guidelines proposed for the Project in order to ensure that impacts are reduced to the maximum extent practicable. Therefore, overall cumulative impacts related to light and glare would be less than significant. F. Impacts and Mitigation Measures The Project would not result in any significant project-specific or cumulative impacts related to aesthetics and therefore no mitigation measures are required

93 4.2 AIR QUALITY This chapter examines the potential air quality impacts associated with development on the Project site as proposed for the Walnut Creek BART Station Transit Village. This chapter is based on the methodology recommended by the Bay Area Air Quality Management District (BAAQMD) and modeling conducted using the California Emissions Estimator Model (CalEEMod) and U.S. Environmental Protection Agency s (US EPA) Industrial Source Complex (ISCST3) dispersion model. In addition, long-term on-site community risk and hazard impacts are based on an analysis prepared by Illingworth & Rodkin, Inc. (I&R) in February CalEEMod output files are included in Appendix B1, the Construction Health Risk Assessment Report and ISCST3 dispersion modeling files are included in Appendix B2, and the I&R on-site community risk and hazards appendices are included in Appendix B3. Both short-term construction emissions as well as long-term effects related to the ongoing operation of the Project are discussed. The analysis contained herein focuses on air pollution from regional emissions and localized pollutant concentrations. Emission refers to the actual quantity of pollutant, measured in pounds per day. Concentration refers to the amount of pollutant material per volumetric unit of air. Concentrations are measured in parts per million (ppm) or micrograms per cubic meter (µg/m 3 ). A. Regulatory Setting This section summarizes key federal, State and City statutes, regulations and policies that would apply to the Project. Ambient air quality standards (AAQS) have been adopted at State and federal levels for criteria air pollutants. AAQS are the levels of air quality considered to provide a margin of safety in the protection of the public health and welfare. They are designed to protect those sensitive receptors most susceptible to further respiratory distress, such as asthmatics, the elderly, very young children, people already weakened by other disease or illness, and persons engaged in strenuous work or exercise. Healthy adults can tolerate occasional exposure to air pollutant concentrations considerably above these minimum standards before adverse effects are observed. In addition, both the State and federal governments regulate the release of toxic air contaminants (TACs). The Project site is in the 4.2-1

94 AIR QUALITY San Francisco Bay Area Air Basin (SFBAAB) and is subject to the rules and regulations imposed by BAAQMD, as well as the California AAQS adopted by the California Air Resources Board (CARB) and National AAQS adopted by the US EPA. 1. Federal Laws and Regulations The Clean Air Act (CAA) was passed in 1963 by the U.S. Congress and has been amended several times. The 1970 Clean Air Act amendments strengthened previous legislation and laid the foundation for the regulatory scheme of the 1970s and 1980s. In 1977, Congress again added several provisions, including nonattainment requirements for areas not meeting National AAQS and the Prevention of Significant Deterioration program. The 1990 amendments represent the latest in a series of federal efforts to regulate the protection of air quality in the United States. The US EPA regulates emission sources that are under the exclusive authority of the federal government, such as aircraft, ships, and certain types of locomotives. The agency has jurisdiction over emission sources outside State waters (i.e. beyond the outer continental shelf) and establishes various emission standards, including those for vehicles sold in states other than California. Automobiles sold in California must meet the stricter emission standards established by CARB. 2. State Laws and Regulations The CAA allows states to adopt more stringent standards or to include other pollution species. The California Clean Air Act (California CAA), signed into law in 1988, requires all areas of the State to achieve and maintain the California AAQS by the earliest practical date. The California AAQS tend to be more restrictive than the National AAQS, based on even greater health and welfare concerns. Federal and State air quality standards are shown in Table a. California Air Resources Board CARB, which is part of the California Environmental Protection Agency, is responsible for meeting the State requirements of the federal CAA, administering the California CAA, and establishing the California AAQS. The 4.2-2

95 BART TRANSIT VIALLGE DRAFT EI R AIR QUALITY TABLE AMBIENT AIR QUALITY STANDARDS FOR CRITERIA POLLUTANTS Pollutant Averaging Time California Standard Federal Primary Standard Major Pollutant Sources Ozone (O3) Carbon Monoxide (CO) Nitrogen Dioxide (NO2) 1 hour 0.09 ppm * 8 hours ppm ppm 1 hour 20 ppm 35 ppm 8 hours 9.0 ppm 9 ppm Annual Average ppm ppm 1 hour 0.18 ppm ppm Motor vehicles, paints, coatings, and solvents. Internal combustion engines, primarily gasoline-powered motor vehicles. Motor vehicles, petroleum-refining operations, industrial sources, aircraft, ships, and railroads. Sulfur Dioxide (SO2) Annual Average * * a 1 hour 0.25 ppm ppm 24 hours 0.04 ppm * a Fuel combustion, chemical plants, sulfur recovery plants, and metal processing. Suspended Particulate Matter (PM10) Suspended Particulate Matter (PM2.5 ) Annual 20 µg/m 3 * Dust and fume-producing construction, industrial, and agricultural operations, Arithmetic Mean combustion, atmospheric photochemical reactions, and natural activities (e.g. wind-raised 24 hours 50 µg/m µg/m 3 dust and ocean sprays). Annual 12 µg/m 3 15 µg/m 3 Dust and fume-producing construction, industrial, and agricultural operations, Arithmetic Mean combustion, atmospheric photochemical reactions, and natural activities (e.g. wind-raised 24 hours * 35 µg/m 3 dust and ocean sprays)

96 CITY OF LAFAYETTE THE TERRACES OF LAFAYETTE DRAFT EI R AIR QUALITY TABLE AMBIENT AIR QUALITY STANDARDS FOR CRITERIA POLLUTANTS (CONTINUED) Lead (Pb) Pollutant Averaging Time California Standard Federal Primary Standard Monthly 1.5 µg/m 3 * Quarterly * 1.5 µg/m 3 3-Month Average * 0.15 µg/m 3 Major Pollutant Sources Present source: lead smelters, battery manufacturing & recycling facilities. Past source: combustion of leaded gasoline. Sulfates (SO4) 24 hours 25 µg/m 3 * Industrial processes. Visibility Reducing Particles 8 hours ExCo =0.23/km visibility of 10 miles a No Federal Standard Visibility-reducing particles consist of suspended particulate matter, which is a complex mixture of tiny particles that consists of dry solid fragments, solid cores with liquid coatings, and small droplets of liquid. These particles vary greatly in shape, size, and chemical composition, and can be made up of many different materials such as metals, soot, soil, dust, and salt. Hydrogen Sulfide 1 hour 0.03 ppm No Federal Standard Hydrogen sulfide (H2S) is a colorless gas with the odor of rotten eggs. It is formed during bacterial decomposition of sulfur-containing organic substances. Also, it can be present in sewer gas and some natural gas, and can be emitted as the result of geothermal energy exploitation. Vinyl Chloride 24 hour 0.01 ppm No Federal Standard Notes: ppm: parts per million; µg/m 3 : micrograms per cubic meter * Standard has not been established for this pollutant/duration by this entity. a On June 2, 2010, a new 1-hour SO2 standard was established and the existing 24-hour and annual primary standards were revoked. Source: California Air Resources Board (CARB), Ambient Air Quality Standards, Vinyl chloride (chloroethene), a chlorinated hydrocarbon, is a colorless gas with a mild, sweet odor. Most vinyl chloride is used to make polyvinyl chloride (PVC) plastic and vinyl products. Vinyl chloride has been detected near landfills, sewage plants, and hazardous waste sites, due to microbial breakdown of chlorinated solvents

97 AIR QUALITY California CAA, as amended in 1992, requires all air districts in the state to endeavor to achieve and maintain the California AAQS. CARB regulates mobile air pollution sources, such as motor vehicles. The agency is responsible for setting emission standards for vehicles sold in California and for other emission sources, such as consumer products and certain off-road equipment. CARB established passenger vehicle fuel specifications, which became effective on March CARB oversees the functions of local air pollution control districts and air quality management districts, which in turn administer air quality activities at the regional and county level. CARB also monitors ambient air quality throughout the State. CARB highlights the potential health impacts associated with proximity to common air pollution sources so that those issues are considered in the planning process. In 2005, CARB made recommendations regarding the siting of new sensitive land uses near freeways, truck distribution centers, rail yards, marine ports, dry cleaners, gasoline dispensing stations, and other air pollution sources. These advisory recommendations include general setbacks or buffers from air pollution sources. b. Criteria Air Pollutants and Ambient Air Quality Standards The federal and California Clean Air Acts establish AAQS for criteria air pollutants. The National AAQS established seven criteria pollutants: carbon monoxide (CO), ozone (O3), nitrogen dioxide (NO2), particulate matter with a diameter less than 10 microns (PM10), particulate matter with a diameter less than 2.5 microns (PM2.5), sulfur dioxide (SO2), and lead (Pb). The California AAQS are more stringent than the corresponding federal standards and incorporate additional standards for sulfates, hydrogen sulfide, vinyl chloride, and visibility reducing particles. Carbon Monoxide (CO) is a colorless, odorless, toxic gas produced by incomplete combustion of carbon substances, such as gasoline or diesel fuel. CO is a primary criteria air pollutant. CO concentrations tend to be the highest during winter mornings with little or no wind, when surface-based inversions trap the pollutant at ground levels. CO is emitted 4.2-5

98 AIR QUALITY directly from internal combustion engines, and motor vehicles operating at slow speeds are the primary source of CO in the SFBAAB. Emissions are highest during cold starts, hard acceleration, stop-and-go driving, and when a vehicle is moving at low speeds. New findings indicate that CO emissions per mile are lowest at about 45 mph for the average light-duty motor vehicle and begin to increase again at higher speeds. When inhaled at high concentrations, CO combines with hemoglobin in the blood and reduces its oxygen-carrying capacity. This results in reduced oxygen reaching the brain, heart, and other body tissues. This condition is especially critical for people with cardiovascular diseases, chronic lung disease, or anemia, as well as fetuses. Even healthy people exposed to high CO concentrations can experience headaches, dizziness, fatigue, unconsciousness, and even death. 1 The SFBAAB is designated under the California and National AAQS as being in attainment of CO criteria levels. 2 Reactive Organic Gases (ROGs) are compounds composed primarily of hydrogen and carbon atoms. Internal combustion associated with motor vehicle usage is the major source of hydrocarbons. Other sources of ROGs include evaporative emissions from paints and solvents, the application of asphalt paving, and the use of household consumer products such as aerosols. Adverse effects on human health are not caused directly by ROGs, but rather by reactions of ROGs to form secondary pollutants such as O3. There are no AAQS established for ROGs. However, because they contribute to the formation of O3, the BAAQMD has established a significance threshold for this pollutant. Nitrogen Oxides (NOX) are a byproduct of fuel combustion and contribute to the formation of O3, PM10, and PM2.5. The two major components of NOX are nitric oxide (NO) and nitrogen dioxide (NO2). The 1 Bay Area Air Quality Management District (BAAQMD), California Environmental Quality Act Air Quality Guidelines, Appendix C: Sample Air Quality Setting. 2 California Air Resources Board (CARB), Area Designations: Activities and Maps, accessed on February 16,

99 AIR QUALITY principal component of NOx produced by combustion is NO, but NO reacts with oxygen to form NO2, creating the mixture of NO and NO2 commonly called NOX. NO2 acts as an acute irritant and, in equal concentrations, is more injurious than NO. At atmospheric concentrations, however, NO2 is only potentially irritating. There is some indication of a relationship between NO2 and chronic pulmonary fibrosis. Some increase in bronchitis in children (two and three years old) has also been observed at concentrations below 0.3 ppm. NO2 absorbs blue light; the result is a brownish-red cast to the atmosphere and reduced visibility. NO is a colorless, odorless gas formed from atmospheric nitrogen and oxygen when combustion takes place under high temperature and/or high pressure. The SFBAAB is designated as an attainment area for NO2 under the National AAQS and California AAQS. 3 Sulfur Dioxide (SO2) is a colorless, pungent, irritating gas formed by the combustion of sulfurous fossil fuels. It enters the atmosphere as a result of burning high-sulfur-content fuel oils and coal and from chemical processes at chemical plants and refineries. Gasoline and natural gas have very low sulfur content and do not release significant quantities of SO2. When SO2 forms sulfates (SO4) in the atmosphere, together these pollutants are referred to as sulfur oxides (SOx). Thus, SO2 is both a primary and secondary criteria air pollutant. At sufficiently high concentrations, SO2 may irritate the upper respiratory tract. At lower concentrations and when combined with particulates, SO2 may do greater harm by injur- 3 California Air Resources Board (CARB), Area Designations: Activities and Maps, accessed on February 16,

100 AIR QUALITY ing lung tissue. 4 The SFBAAB is designated as an attainment area for SO2 under the California and National AAQS. 5 Suspended Particulate Matter (PM10 and PM2.5) consists of finely divided solids or liquids such as soot, dust, aerosols, fumes, and mists. Two forms of fine particulates are now recognized and regulated. Inhalable coarse particles, or PM10, include the particulate matter with an aerodynamic diameter of 10 microns (i.e. 10 millionths of a meter or inch) or less. Inhalable fine particles, or PM2.5, have an aerodynamic diameter of 2.5 microns or less (i.e. 2.5 millionths of a meter or inch). Some particulate matter, such as pollen, occurs naturally. In the SFBAAB most particulate matter is caused by combustion, factories, construction, grading, demolition, agricultural activities, and motor vehicles. Extended exposure to particulate matter can increase the risk of chronic respiratory disease. PM10 is of concern because it bypasses the body s natural filtration system more easily than larger particles, and can lodge deep in the lungs. PM2.5 poses an increased health risk because the particles can deposit deep in the lungs and contain substances that are particularly harmful to human health. Motor vehicles are currently responsible for about half of particulates in the SFBAAB. Wood burning in fireplaces and stoves is another large source of fine particulates. 6 Both PM10 and PM2.5 may adversely affect the human respiratory system, especially in people who are naturally sensitive or susceptible to breathing problems. These health effects include premature death and increased 4 Bay Area Air Quality Management District (BAAQMD), 2011, California Environmental Quality Act Air Quality Guidelines, Appendix C: Sample Air Quality Setting. 5 California Air Resources Board (CARB), 2011, Area Designations: Activities and Maps, accessed on February 16, Bay Area Air Quality Management District (BAAQMD), 2011, California Environmental Quality Act Air Quality Guidelines, Appendix C: Sample Air Quality Setting

101 AIR QUALITY hospital admissions and emergency room visits (primarily the elderly and individuals with cardiopulmonary disease); increased respiratory symptoms and disease (children and individual with asthma); and alterations in lung tissue and structure and in respiratory tract defense mechanisms. 7 Diesel particulate matter (DPM) is classified by CARB as a carcinogen. The SFBAAB is designated as nonattainment under the California AAQS for PM10 and nonattainment under both the California and National AAQS for PM Ozone (O3) is commonly referred to as smog and is a gas that is formed when ROGs and NOX, both by-products of internal combustion engine exhaust, undergo photochemical reactions in the presence of sunlight. O3 is a secondary criteria air pollutant. O3 concentrations are generally highest during the summer months when direct sunlight, light winds, and warm temperatures create favorable conditions to the formation of this pollutant. O3 poses a health threat to those who already suffer from respiratory diseases as well as to healthy people. O3 levels usually build up during the day and peak in the afternoon hours. Short-term exposure can irritate the eyes and cause constriction of the airways. Besides causing shortness of breath, it can aggravate existing respiratory diseases such as asthma, bronchitis, and emphysema. Chronic exposure to high ozone levels can permanently damage lung tissue. O3 can also damage plants and trees and materials such as rubber and fabrics. 9 The SFBAAB is des- 7 South Coast Air Quality Management District, Guidance Document for Addressing Air Quality Issues in General Plans and Local Planning. 8 California Air Resources Board (CARB), Area Designations: Activities and Maps, accessed on February 16, Bay Area Air Quality Management District (BAAQMD), California Environmental Quality Act Air Quality Guidelines, Appendix C: Sample Air Quality Setting

102 AIR QUALITY ignated as nonattainment of the 1-hour California AAQS and 8-hour California and National AAQS for O3. 10 Lead (Pb) is a metal found naturally in the environment as well as in manufactured products. The major sources of lead emissions have historically been mobile and industrial sources. As a result of the phase-out of leaded gasoline, metal processing is currently the primary source of lead emissions. The highest levels of lead in air are generally found near lead smelters. Other stationary sources are waste incinerators, utilities, and lead-acid battery manufacturers. Twenty years ago, mobile sources were the main contributor to ambient lead concentrations in the air. In the early 1970s, the EPA set national regulations to gradually reduce the lead content in gasoline. In 1975, unleaded gasoline was introduced for motor vehicles equipped with catalytic converters. The EPA banned the use of leaded gasoline in highway vehicles in December As a result of the EPA s regulatory efforts to remove lead from gasoline, emissions of lead from the transportation sector and levels of lead in the air decreased dramatically. 11 The SFBAAB is designated as in attainment of the California and National AAQS for lead. 12 c. Toxic Air Contaminants (TACs) Public exposure to TACs is a significant environmental health issue in California. In 1983, the California Legislature enacted a program to identify the health effects of TACs and to reduce exposure to these contaminants to protect public health. The California Health and Safety Code section 39655(a) 10 California Air Resources Board (CARB), Area Designations: Activities and Maps, accessed on February 16, Bay Area Air Quality Management District (BAAQMD), California Environmental Quality Act Air Quality Guidelines, Appendix C: Sample Air Quality Setting. 12 California Air Resources Board (CARB), Area Designations: Activities and Maps, accessed on February 16,

103 AIR QUALITY defines a TAC as an air pollutant which may cause or contribute to an increase in mortality or in serious illness, or which may pose a present or potential hazard to human health. A substance that is listed as a hazardous air pollutant pursuant to Section 112(b) of the federal Clean Air Act (42 United States Code Section 7412[b]) is a toxic air contaminant. Under State law, the California Environmental Protection Agency (Cal/EPA), acting through CARB, is authorized to identify a substance as a TAC if it determines that the substance is an air pollutant that may cause or contribute to an increase in mortality or serious illness, or may pose a present or potential hazard to human health. California regulates TACs primarily through AB 1807 (Tanner Air Toxics Act) and AB 2588 (Air Toxics Hot Spot Information and Assessment Act of 1987). The Tanner Air Toxics Act sets forth a formal procedure for CARB to designate substances as TACs. Once a TAC is identified, CARB adopts an airborne toxics control measure for sources that emit designated TACs. If there is a safe threshold for a substance (i.e. a point below which there is no toxic effect), the control measure must reduce exposure to below that threshold. If there is no safe threshold, the measure must incorporate best available control technology to minimize emissions. To date, CARB has established formal control measures for 11 TACs, all of which are identified as having no safe threshold. Air toxics from stationary sources are also regulated in California under the Air Toxics Hot Spot Information and Assessment Act of 1987 (Assembly Bill 2588). Under AB 2588, TAC emissions from individual facilities are quantified and prioritized by the air quality management district or air pollution control district. High priority facilities are required to perform a health risk assessment (HRA) and, if specific thresholds are exceeded, are required to communicate the results to the public through notices and public meetings

104 AIR QUALITY By the last update to the TAC list in December 1999, CARB had designated 244 compounds as TACs. 13 Additionally, CARB has implemented control measures for a number of compounds that pose high risks and show potential for effective control. The majority of the estimated health risks from TACs can be attributed to relatively few compounds, the most important being particulate matter from diesel-fueled engines. In 1998, CARB identified DPM as a TAC. Previously, the individual chemical compounds in diesel exhaust were considered TACs. Almost all diesel exhaust particles are 10 microns or less in diameter. Because of their extremely small size, these particles can be inhaled and eventually trapped in the bronchial and alveolar regions of the lungs. BAAQMD s Community Air Risk Evaluation (CARE) program was initiated in 2004 to evaluate and reduce health risks associated with exposures to outdoor TACs in the Bay Area. Based on the annual emissions inventory of TACs for the SFBAAB, DPM was found to account for approximately 80 percent of the cancer risk from airborne toxics. The highest DPM concentrations occur in the urban core areas of eastern San Francisco, western Alameda, and northwestern Santa Clara counties. The major contributor to acute and chronic non-cancer health effects in the SFBAAB is acrolein (C3H4O). Major sources of acrolein include on-road mobile sources and aircrafts near freeways and commercial and military airports. 14 d. Bay Area Air Quality Management District In 1955, the California Legislature created BAAQMD. The agency is primarily responsible for assuring that the national and California AAQS are attained and maintained in the SFBAAB. BAAQMD regulates air quality within Walnut Creek. BAAQMD is responsible for many other activities, including: 13 CARB, California Air Resources Board (CARB). Final Staff Report: Update to the Toxic Air Contaminant List. 14 Bay Area Air Quality Management District (BAAQMD), Community Air Risk Evaluation Program, Phase I Findings and Policy Recommendations Related to Toxic Air Contaminants in the San Francisco Bay Area

105 AIR QUALITY Adopting and enforcing rules and regulations concerning air pollutant sources. Issuing permits for stationary sources of air pollutants. Inspecting stationary sources of air pollutants. Responding to citizen complaints. Monitoring ambient air quality and meteorological conditions. Awarding grants to reduce motor vehicle emissions. Conducting public education campaigns. e. Air Quality Management Planning Air quality conditions in the SFBAAB have improved significantly since the BAAQMD was created in The BAAQMD prepares air quality management plans (AQMPs) to attain ambient air quality standards in the SFBAAB. The BAAQMD prepares Ozone Attainment Plans (OAPs) for the National O3 standard and Clean Air Plans for the California O3 standard. The BAAQMD prepares these AQMPs in coordination with the Association of Bay Area Governments (ABAG) and the Metropolitan Transportation Commission (MTC). The most recent adopted comprehensive plan is the 2010 Bay Area Clean Air Plan, which was adopted on September 15, 2010, and incorporates significant new scientific data, primarily in the form of updated emissions inventories, ambient measurements, new meteorological episodes, and new air quality modeling tools. The purpose of the 2010 Clean Air Plan is to: 1) update the Bay Area 2005 Ozone Strategy in accordance with the requirements of the California Clean Air Act to implement all feasible measures to reduce O3; 2) consider the impacts of O3 control measures on PM, TAC, and greenhouse gases (GHGs) in a single, integrated plan; 3) review progress in improving air quality in recent years; and 4) establish emission control measures to be adopted or implemented in the 2010 to 2012 timeframe. The 2010 Clean Air Plan also provides 15 Bay Area Air Quality Management District (BAAQMD), California Environmental Quality Act Air Quality Guidelines, Appendix C: Sample Air Quality Setting

106 AIR QUALITY the framework for SFBAAB to achieve attainment of the California AAQS. Areas that meet AAQS are classified attainment areas, while areas that do not meet these standards are classified nonattainment areas. Severity classifications for O3 range from marginal, moderate, and serious to severe and extreme. The attainment status for the SFBAAB is shown in Table The SFBAAB is currently designated as a nonattainment area for California and National O3, California and National PM2.5, and California PM10 AAQS. 3. Local Policies Chapter 4, Built Environment, of the Walnut Creek General Plan 2025 includes the following policies relevant to the quality of the air in Walnut Creek. Goal 31 Strive to meet state and federal air quality standards for the region. Policy 31.1 Work with the Bay Area Air Quality Management District (BAAQMD) and the County in promoting better air quality. Policy 31.2 Consider additional land use and development criteria, standards, and decisions that have positive impacts on air quality and quality of life in general. Policy 31.3 Proactively manage local air quality issues. B. Existing Conditions This section describes existing conditions related to air quality in Walnut Creek and the Project area. 1. San Francisco Air Basin The BAAQMD is the regional air quality agency for the SFBAAB, which comprises all of Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, and Santa Clara counties; the southern portion of Sonoma County, and the southwestern portion of Solano County. Air quality in this area is

107 AIR QUALITY TABLE ATTAINMENT STATUS OF CRITERIA POLLUTANTS IN THE SAN FRANCISCO AIR BASIN Pollutant State Federal Ozone 1-hour Nonattainment Nonattainment Ozone 8-hour Nonattainment (serious) Classification revoked (2005) PM10 Nonattainment Unclassified PM2.5 Nonattainment Nonattainment CO Attainment Attainment NO2 Attainment Attainment SO2 Attainment Attainment Lead Attainment Attainment Sulfates Attainment Unclassified All others Unclassified Unclassified Source: California Air Resources Board (CARBP), Area Designations: Activities and Maps, accessed on February 16, determined by such natural factors as topography, meteorology, and climate, in addition to the presence of existing air pollution sources and ambient conditions. 16 a. Meteorology Walnut Creek s meteorological conditions are warm and mainly dry in the summers, and mild and moderately wet in the winters. Marine air has a moderating effect on the climate throughout much of the year, as Walnut Creek 16 Bay Area Air Quality Management District (BAAQMD), California Environmental Quality Act Air Quality Guidelines, Appendix C: Sample Air Quality Setting

108 AIR QUALITY lies within the coastal valleys of the SFBAAB. Winds flow through the Golden Gate from the Pacific Ocean, but direct flow into Walnut Creek is impeded by the East Bay Hills. Marine air is mostly blocked from the area until late afternoons or on days when deep marine inversions develop with strong on-shore flows. b. Wind Patterns Sea breezes and terrain effects influence air quality in Walnut Creek. Winds from the west-southwest are most prevalent during spring and summer afternoons. These are the breezes that travel from the Pacific Ocean through gaps in the East Bay hills. When the ocean breeze is weak, winds become light and variable. In addition, nighttime drainage flows typically develop. On clear nights with light winds, inversions develop in the coastal valleys, separating the surface wind flow from winds aloft. The drainage flow is usually light and stable, flowing towards the Carquinez Strait. Wind speeds in these Coastal Valleys are generally low, about 5 miles per hour on average. Because the Walnut Creek area lies downwind of urban areas, air pollution is transported into the area. c. Temperature Temperatures in Walnut Creek are typical of the Bay Area s inland coast valleys that are minimally affected by exposure to sea breezes. Typical summer temperatures are in the 80s to low 90s F during the day and mid 50s F at night. Typical winter temperatures are in the 50s F during the day and 30s to low 40s F at night. Walnut Creek receives about 20 to 25 inches of annual precipitation, with most of it occurring in the winter months. d. Air Pollution Potential When combined with localized air pollutant emissions, the clear skies with relatively warm conditions that are typical in summer elevate ground-level ozone (O3) levels. Air quality standards for O3 traditionally are exceeded in parts of the SFBAAB when relatively stagnant conditions occur for periods of several days during the warmer months of the year. Weak wind flow patterns combined with strong inversions substantially reduce normal atmospheric

109 AIR QUALITY mixing. Key components of ground-level O3 formation are sunlight and heat; therefore, significant O3 formation only occurs during the months from late spring through early fall. Because of the meteorological conditions that are conducive to a build-up of air pollutants and the transport of air pollutants into the area from both urbanized portions of the Bay Area and the Central Valley, pollution potential is relatively high. Pollutants emitted in the Walnut Creek area, along with some transport from urban or industrial areas, can contribute to localized air quality problems. The light winds that are common in winter can combine with surface-based inversions caused by cold air near the surface, which traps pollutants such as particulates (e.g. wood smoke) and carbon monoxide. This can lead to localized high concentrations of these pollutants. 2. Existing Ambient Air Quality BAAQMD monitors air quality conditions at over 30 locations throughout the Bay Area. The closest monitoring station to the Project site is located in the City of Concord. Criteria pollutants monitored include O3, CO, NO2, SO2, PM10, and PM2.5. The gaseous pollutants (i.e. O3, CO, NO2, and SO2) are monitored continuously while particulate matter (i.e. PM10 and PM2.5) are sampled for 24 hours every sixth day. A summary of the data recorded at the Concord station is shown in Table for the period 2007 through Table also shows the number of days per year that air pollutant levels exceeded National or California AAQS in Concord. Exceedances of O3 (1- or 8-hour concentrations) were recorded at the Concord station each year. The data show occasional violations of the California AAQS for PM10 and reoccurring violations of the National AAQS for PM2.5. The federal PM10, CO, SO2, and NO2 standards have not been exceeded in the last five years in the Project vicinity. 3. Sensitive Receptors Sensitive receptors are people who are particularly susceptible to the adverse effects of air pollution. CARB has identified the following people who are

110 AIR QUALITY TABLE AMBIENT AIR QUALITY MONITORING SUMMARY Pollutant/Standard Ozone (O3) State 1-Hour 0.09 ppm State 8-hour 0.07 ppm Federal 8-Hour > ppm Max. 1-Hour Conc. (ppm) Max. 8-Hour Conc. (ppm) Carbon Monoxide (CO) State 8-Hour > 9.0 ppm Federal 8-Hour 9.0 ppm Max. 8-Hour Conc. (ppm) Nitrogen Dioxide (NO2) State 1-Hour 0.18 (ppm Max. 1-Hour Conc. (ppm) Sulfur Dioxide (SO2) State 24-Hour 0.04 ppm Max. 24-Hour Conc. (ppm) Coarse Particulates (PM10) State 24-Hour > 50 µg/m 3 Federal 24-Hour > 150 µg/m 3 Max. 24-Hour Conc. (µg/ m3 ) Fine Particulates (PM2.5) Federal 24-Hour > 35 µg/m 3 Max. 24-Hour Conc. (µg/m 3 ) Number of Days Threshold Were Exceeded and Maximum Levels During Such Violations Notes: ppm: parts per million; µg/m 3 : or micrograms per cubic meter * = insufficient data Data obtained from the Concord-2975 Treat Boulevard Monitoring Station. Source: CARB California Air Resources Board (CARB) Air Pollution Data Monitoring Cards (2007, 2008, 2009, 2010, and 2011)

111 AIR QUALITY most likely to be affected by air pollution: children, the elderly, the acutely ill, and the chronically ill, especially those with cardio-respiratory diseases. Residential areas are also considered sensitive receptors to air pollution because residents (including children and the elderly) tend to be at home for extended periods of time, resulting in sustained exposure to any pollutants present. Other sensitive receptors include retirement facilities, day care facilities, hospitals, and schools. Both National and California AAQS were developed with the intent to protect sensitive receptors from the adverse impacts of air pollution. C. Standards of Significance 1. CEQA Thresholds The Project would have a significant effect on the environment with respect to air quality if it would: 1. Conflict with or obstruct implementation of the applicable air quality plan. 2. Violate any air quality standard or contribute substantially to an existing or projected air quality violation. 3. Result in a cumulatively considerable net increase of any criteria pollutant for which the Project region is nonattainment under an applicable federal or state ambient air quality standard (including releasing emissions which exceed quantitative thresholds for ozone precursors). 4. Expose sensitive receptors to substantial pollutant concentrations. 5. Create objectionable odors affecting a substantial number of people. The City notes that the purpose of this EIR is to identify the significant effects of the Project on the environment, not the significant effects of the environment on the Project. (South Orange County Wastewater Authority v. City of Dana Point (2011) 196 Cal.App.4th 1604, ; City of Long Beach v. Los Angeles Unified School Dist. (2009) 176 Cal.App.4th 889, 905.) While identifying the environmental effects of attracting development and people to an area

112 AIR QUALITY is consistent with CEQA s legislative purpose and statutory requirements, identifying the effects on the Project and its users of locating the Project in a particular environmental setting is neither consistent with CEQA's legislative purpose nor required by the CEQA statutes. Appendix G of the Guidelines is a sample checklist form that is suggested for use in preparing an initial study, and which the City has employed to assist in the preparation of this Draft EIR (see Guidelines, 15063, subd. (f)). However, a few of the questions on the form concern the exposure of people or structures to environmental hazards and could be construed to refer to not only the Project's exacerbation of environmental hazards but also the effects on users of the Project and structures in the Project of preexisting environmental hazards. To the extent that such questions may encompass the latter effects, the questions do not relate to environmental impacts under CEQA and cannot support an argument that the effects of the environment on the Project must be analyzed in a Draft EIR. (Ballona Wetlands Trust v. City of Los Angeles (2011) 201 Cal.App.4th 455, ) Accordingly, while the City provides the following informational analysis of threshold 4 taken from Appendix G of the CEQA Guidelines, and includes proposed mitigation measures consistent with that analysis, that the Guidelines language in threshold 4 above is not an example of an environmental effect caused by development, but instead is an example of an effect on the Project caused by the environment. Analysis of this information is provided for informational purposes and for full disclosure, but is not required under CEQA. 2. BAAQMD Project-Level Thresholds The BAAQMD adopted CEQA Guidelines in June 2010, which were revised in May ,18 Methodology and thresholds for criteria air pollutant im- 17 On March 5, 2012, the Alameda Superior Court issued a ruling in California Building Industry Association v. Bay Area Air Quality Management District (Superior Court Case No. RG ). Pursuant to the Court s order, the Court found that the adoption of the BAAQMD s CEQA Guidelines was a project requiring CEQA review. No CEQA review was conducted for the CEQA Guidelines prior to their adoption and so the Court has ordered that BAAQMD set aside the Guidelines pending completion of that review. Although the thresholds have been set aside until an

113 AIR QUALITY pacts and community health risk, as set forth in the BAAQMD Guidelines, are utilized in this Draft EIR. The following screening thresholds and significance criteria would be applicable to the proposed Project. If a project exceeds the screening thresholds, it would be required to conduct a full analysis using the significance criteria set forth in the BAAQMD Guidelines: a. Criteria Air Pollutants i. Regional Significance Criteria BAAQMD s criteria for regional significance for projects that exceed the screening thresholds are shown in Table Significance criteria for both the construction and operational phases of the Project are shown. ii. Local CO Hotspots Congested intersections have the potential to create elevated concentrations of CO, referred to as CO hotspots. The significance criteria for CO hotspots are based on the California AAQS for CO, which is 9.0 ppm (8-hour average) and 20.0 ppm (1-hour average). However, with the turnover of older vehicles, introduction of cleaner fuels, and implementation of control technology, the SFBAAB is in attainment of the California and National AAQS, and CO environmental evaluation is conducted, BAAQMD s significance criteria, as outlined in their CEQA Guidelines, are supported by extensive studies and analysis (see gov/divisions/planning-and-research/ceqa-guidelines/tools-and-methodology. aspx). Accordingly, pursuant to its discretion under CEQA Guidelines section (b) ( lead agencies may exercise their discretion on what criteria to use ), and the recent holding in Citizen for Responsible Equitable Environmental Development v. City of Chula Vista (2011) 197 Cal.App.4th 327, , ( [t]he determination of whether a project may have a significant effect on the environment calls for careful judgment on the part of the public agency involved, based to the extent possible on scientific and factual data. ) the City has decided that the BAAQMD CEQA thresholds are based on substantial evidence and therefore can still be applied to the proposed Project. 18 Bay Area Air Quality Management District (BAAQMD), 2011 (Revised). California Environmental Quality Act Air Quality Guidelines. Appendix C: Sample Air Quality Setting

114 AIR QUALITY Table REGIONAL PROJECT-LEVEL CRITERIA AIR POLLUTANT THRESHOLDS Pollutant Construction (lbs/day) Average Daily (lbs/day) Operational Maximum Annual (tpy) Reactive Organic Gases (ROGs) Oxides of Nitrogen (NOx) Coarse Inhalable Particulate Matter (PM10) Fine Inhalable Particulate Matter (PM2.5) 82 (exhaust) (exhaust) PM10/PM2.5 Fugitive Dust BMPs a N/A N/A Notes: BMPs = Best Management Practices N/A = Not Applicable a Construction activities are required to implement BAAQMD s Best Management Practices (BMPs) for fugitive dust control. Source: BAAQMD Bay Area Air Quality Management District. 2011, May (Revised). California Environmental Quality Act Air Quality Guidelines. concentrations in the SFBAAB have steadily declined. Because CO concentrations have improved, BAAQMD does not require a CO hotspot analysis if the following criteria are met: The Project is consistent with an applicable congestion management program established by the County Congestion Management Agency for designated roads or highways, the regional transportation plan, and local congestion management agency plans The Project would not increase traffic volumes at affected intersections to more than 44,000 vehicles per hour The Project traffic would not increase traffic volumes at affected intersections to more than 24,000 vehicles per hour where vertical and/or hori

115 AIR QUALITY zontal mixing is substantially limited (e.g. tunnel, parking garage, bridge underpass, natural or urban street canyon, below-grade roadway). 19 iii. Odors BAAQMD s thresholds for odors are qualitative, and do not consider odors generated from use of construction equipment and activities to be objectionable. For operational phase odor impacts, a project that would result in the siting of a new source of odor or exposure of a new receptor to existing or planned odor sources should consider odor impacts. As set forth in BAAQMD s 2011 Guidelines, certain odor screening thresholds have been established for land uses that have the potential to generate substantial odor complaints, including wastewater treatment plants, landfills or transfer stations, composting facilities, confined animal facilities, food manufacturing, and chemical plants. There are no screening thresholds for projects that are residential or mixed use in nature, since these types of developments do not typically result in the generation of substantial odor complaints. b. Community Risk and Hazards The California Office of Environmental Health Hazard Assessment (OEHHA) has developed exposure assumptions for typical types of sensitive receptors. OEHHA recommends a 70-year lifetime exposure period for determining residential cancer risks. BAAQMD policy for CEQA purposes is to judge impacts based on the 70-year exposure. According to OEHHA, exposure durations of 9 years and 30 years may also be evaluated as supplemental information to show the range of cancer risk based on residency periods. The U.S. EPA considers 9 years to be the estimate of average residence time, 30-years to be the high-end of residence time, and 70-years to be representative of a lifetime exposure. The 70-year exposure period ensures that a person residing in the vicinity of a freeway for a lifetime would be included in the evaluation. The lifetime (or 70-year exposure) has been the historical benchmark for comparing facility impacts on sensitive receptors. OEHHA 19 Bay Area Air Quality Management District (BAAQMD), 2011 (Revised). California Environmental Quality Act Air Quality Guidelines

116 AIR QUALITY recognizes that although it is not likely that most people will reside at a single residence for 70 years, it is common that people will spend their entire lives in a major urban area, where continual exposure is likely. BAAQMD s significance thresholds for local community risk and hazard impacts apply to both the siting of a new source and to the siting of a new receptor. Local community risk and hazard impacts are associated with TACs and PM2.5 because emissions of these pollutants can have significant health impacts at the local level. For assessing community risk and hazards, sources within a 1,000-foot radius are considered. Sources are defined as freeways, high volume roadways (with volumes of 10,000 vehicles or more per day or 1,000 trucks per day), and permitted sources. 20 Interstate 680, Ygnacio Valley Road, California Boulevard, and Main Street are roadways with more than 10,000 vehicles a day. 21 There also are eight stationary sources consisting of emergency diesel generators and gasoline stations within a 1,000- foot radius of the site. i. Siting a New Receptor: Project-Level Community Risk Project-level emissions of TACs or PM2.5 from individual sources within 1,000 feet of the Project that exceed any of the thresholds listed below are considered a potentially significant community health risk: Non-compliance with a qualified Community Risk Reduction Plan; 22 An excess cancer risk level of more than 10 in one million, or a noncancer (i.e. chronic or acute) hazard index greater than 1.0 would be a significant impact; 20 Bay Area Air Quality Management District (BAAQMD), 2011 (Revised). California Environmental Quality Act Air Quality Guidelines. 21 Average daily traffic volumes were derived based on the traffic report prepared by Fehr and Peers. 22 There is no Community Risk Reduction Plan applicable to the project, so this threshold is inapplicable

117 AIR QUALITY An incremental increase of greater than 0.3 micrograms per cubic meter (μg/m 3 ) annual average PM2.5 from a single source would be a significant cumulatively considerable contribution. 23 ii. Siting a New Receptor: Cumulative Community Risk Cumulative sources represent the combined total risk values of each of the individual sources within the 1,000-foot evaluation zone. A project would have a cumulatively considerable impact if the aggregate total of all past, present, and reasonably foreseeable future sources within a 1,000-foot radius from the fence line of a source or location of a receptor, plus the contribution from the Project, exceeds the following: Non-compliance with a qualified Community Risk Reduction Plan; or An excess cancer risk levels of more than 100 in one million or a chronic non-cancer hazard index (from all local sources) greater than 10.0; or 0.8 μg/m 3 annual average PM iii. Construction Risk The Threshold of Significance for construction-related local community risk and hazard impacts is the same as for Project operations: excess cancer risk level of more than 10 in one million, or a non-cancer (i.e. chronic or acute) hazard index greater than 1.0. BAAQMD has adopted screening tables for air toxics evaluation during construction. 25 Construction-related TAC and PM impacts are addressed on a case-by-case basis, taking into consideration the specific construction-related characteristics of each project and proximity to off-site receptors, as applicable Bay Area Air Quality Management District (BAAQMD), 2011 (Revised). California Environmental Quality Act Air Quality Guidelines. 24 Bay Area Air Quality Management District (BAAQMD), 2011 (Revised). California Environmental Quality Act Air Quality Guidelines. 25 Bay Area Air Quality Management District (BAAQMD), Screening Tables for Air Toxics Evaluations during Construction. 26 Bay Area Air Quality Management District (BAAQMD), 2011 (Revised). California Environmental Quality Act Air Quality Guidelines

118 AIR QUALITY D. Impact Discussion This section provides a discussion of the potential impacts related to air quality that could occur as a result of the Project. 1. Project Impacts a. Would the Project violate any air quality standard or contribute substantially to an existing or projected air quality violation? i. Impacts of Construction BAAQMD s approach to the CEQA analysis of construction impacts is to address construction impacts in the following manner: Ensure appropriate control measures are implemented to reduce fugitive emissions of PM10 and PM2.5; Compare average daily exhaust emissions of NOx, PM10, and PM2.5 and exhaust and evaporative emissions of ROGs to significance thresholds; and Evaluate exposure of sensitive receptors to construction activities with respect to community risk thresholds that include cancer risk, non-cancer risk, and annual PM2.5 concentrations (see Impact c [ii]). a) Construction-Related Regional Criteria Air Pollutants Project construction would require demolition, grading, excavation, paving, and construction of new buildings. Although construction activities would be temporary, they have the potential to cause both air quality nuisance and health impacts, and possibly cause localized air quality violations due to PM10 emissions. Off-road construction equipment is also a source of NOx emissions, which can contribute to regional levels of O3 and particulate matter in the region. Paints and solvents used in construction can produce temporary ROG emissions. As described below, the BAAQMD CEQA Air Quality Guidelines identify thresholds to judge temporary construction impacts of criteria air pollutant emissions during construction

119 AIR QUALITY Although the construction schedule and Project designs are preliminary, construction activities are anticipated to begin in 2013 and take place in three, non-overlapping, phases with completion in Construction period emissions were modeled for each construction phase using the California Emissions Estimator Model (CalEEMod), version Although, this model has not yet been integrated with the latest CARB emission factors for on-road (EMFAC2011) and off-road (OFFROAD2011) sources, CalEEMod represents the most up to date tool for quantifying impacts in CEQA documents. Construction equipment mix and phasing was provided by the Project Applicant. Except where noted, default model inputs were used to predict annual construction emissions in terms of tons per year. The load factors for construction equipment were adjusted downward by 33 percent to be consistent with the latest CARB modeling guidance used in the OFFROAD2011 emissions model. Average daily emissions were determined by dividing the annual emissions by the estimated number of construction days for each construction phase. Annual and daily construction emissions and the CalEEMod model output are provided in Appendix B1. Preliminary estimates of daily construction emissions from the different build out phases of the Project were predicted. These emissions are reported in Table As shown in Table 4.2-5, emissions from construction equipment exhaust do not exceed the BAAQMD daily thresholds. However, BAAQMD recommends implementing all of the Basic Control Measures it has identified in its Guidelines whether or not construction-related emissions exceed the thresholds. PM10 is typically the most significant source of air pollution from the dust generated from construction. The amount of dust generated during construction would be highly variable and is dependent on the size of the area disturbed at one time along with the amount of activity, the equipment being operated, soil conditions and meteorological conditions. If uncontrolled, PM10 and PM2.5 levels downwind of actively disturbed areas could possibly exceed State standards. Consequently, construction-related criteria pollutant emissions are less than significant; however, the City requires the implementation of BAAQMD s Basic Control Measures in accordance with BAAQMD s recommendation, as set forth in Impact AQ

120 AIR QUALITY TABLE AVERAGE DAILY AIR POLLUTANT EMISSIONS FROM CON- STRUCTION (POUNDS PER DAY) Description Reactive Organic Gases Nitrogen Oxides Exhaust Particulate Matter (PM10) Exhaust Fine Particulate Matter (PM2.5) Phase I 35 lbs/day 48 lbs/day 2 lbs/day 2 lbs/day Phase II 39 lbs/day 44 lbs/day 2 lbs/day 2 lbs/day Phase II 30 lbs/day 34 lbs/day 2 lbs/day 2 lbs/day BAAQMD Significance Threshold 54 lb/day 54 lb/day 82 lb/day 54 lb/day Exceeds Threshold No No No No Source: CalEEMod, Version Average daily emissions are based on the annual construction model run and divided by the total number of construction days. Air quality modeling is based on the construction schedule and construction equipment use provided by the Project applicant. Pursuant to the Project Applicant, construction of Phase I, Phase II, and Phase III would not overlap. i. Impacts of Operations The BAAQMD significance thresholds are for O3 emissions of precursor pollutants (ROGs and NOx) and particulate matter exhaust emissions (PM10 and PM2.5). Project direct and indirect emissions are computed and compared to the BAAQMD regional thresholds. CO is addressed through the potential for violations of ambient air quality standards at congested intersections affected by the Project (see Impact c [iii]). a) Operational Phase Regional Criteria Air Pollutants The Project would add new traffic trips, which would lead to increased emissions of air pollutants. In addition, there would be area source emissions from heating of space and water, cooking, and use of landscape equipment

121 AIR QUALITY All stationary sources of air pollution that could be part of the Project have been identified. 27 Vehicle emissions were calculated using the CalEEMod with the Project land uses and trip generation forecasts made by AECOM (see Chapter 4.11 of this EIR) for buildout of the Project in The total square footages for the various land uses (e.g. residential, office, retail, etc.) were input to the model. Trip generation rates in CalEEMod were adjusted to reflect the traffic study predictions that take into account the mix of uses, retail pass-by trips, and transit usage. CalEEMod predicts emissions from area sources such as natural gas combustion, fireplaces, and use of consumer products and paints. Default values in the model were used with the following exceptions: All residences were assumed to use natural gas for space and water heating; All fireplaces were assumed to be fueled by natural gas and there would be no wood burning; and No woodstoves would be included in the Project. ROG content limits for Architectural Coatings would be 150 grams per liter, per BAAQMD s Compliance Advisory for New Architectural Coatings Requirements, issued Feb 15, Stationary sources of criteria air pollutants could include emergency standby generators to provide some electricity during power outages or natural gas-fired boilers used for heating of air and/or water. Such sources would require permits from the BAAQMD. Emergency generators would be used infrequently and usually only for short periods of time for testing. Emissions associated with this type of use would be minor and very small compared to those generated by Project traffic. Emissions from the existing BART generator were modeled for the community risk assessment and the results are provided in Appendix B3. Emissions from natural gas-fired boilers would also be small, but are accounted for in CalEEMod of area sources that account for emissions from space and water heating

122 AIR QUALITY Annual and average daily air emissions predicted with full buildout of the proposed Project in 2018 are reported in Table and compared against BAAQMD thresholds. This table shows that emissions of regional air pollutants (i.e. O3 precursor pollutants and particulate matter) would be below the significance thresholds contained in the BAAQMD CEQA Air Quality Guidelines. As a result, the Project would have a less-than-significant impact on regional air quality. b. Would the Project result in a cumulatively considerable net increase of any criteria pollutant for which the Project region is nonattainment under an applicable federal or state ambient air quality standard (including releasing emissions which exceed quantitative thresholds for ozone precursors)? With respect to criteria air pollutants, the development of the Project was not found to result in any short-term or long-term air quality impacts. Project direct and indirect emissions were calculated and compared to BAAQMD thresholds and not found to have a cumulatively considerable net increase of O3 precursor pollutants, PM10 or PM2.5. Localized emissions from cumulative traffic conditions were not found to cause or contribute to a violation of an ambient air quality standard. Under the BAAQMD CEQA Guidelines, significant cumulative impacts to air quality do not result from projects that have less-than-significant impacts and do not conflict with regional clean air planning efforts. In addition, as discussed in Subsection d below, the Project would not conflict with regional clean air planning efforts and would not otherwise have significant impacts on air quality. In fact, since the proposed Project would be an urban infill mixed-use transit-oriented development, vehicle trips generated from the Project are projected to be lower than traditional development in Walnut Creek due to the proximity to regional transit and on-site commercial uses. This would support regional planning initiatives to reduce vehicle miles traveled (VMT) and associated air quality impacts. Therefore, this would result in a less-than-significant cumulative impact

123 AIR QUALITY TABLE REGIONAL AIR POLLUTANT EMISSIONS IN 2018 Description Project Annual Emissions Project Average Daily Emissions BAAQMD Project Significance Thresholds Reactive Organic Gases Nitrogen Oxides 9 tons/year 5 tons/year Exhaust Particulate Matter (PM10) 0.21 tons/year Exhaust Particulate Matter (PM2.5) 0.18 tons/year 50 lbs/day 27 lbs/day 1.2 lbs/day 1.0 lbs/day 10 tons/year or 54 lbs/day 10 tons/year or 54 lbs/day 15 tons/year or 82 lbs/day 10 tons/year or 54 lbs/day Exceeds Threshold? No No No No Source: CalEEMod, Version Average daily emissions are based on the annual operational model run and divided by 365 days per year. c. Would the Project expose Sensitive Receptors or the General Public to Substantial Pollutant Concentrations? i. CO Hotspots CO emissions from traffic generated by the Project would be the pollutant of greatest concern at the local level. Since 1998, CO emissions in the Bay Area region have remained below State and federal standards. Monitoring data from all ambient air quality monitoring stations in the Bay Area indicate that existing carbon monoxide levels are currently below national and California ambient air quality standards. Monitored CO levels have decreased substantially since 1990 as newer vehicles with greatly improved exhaust emission control systems have replaced older vehicles. The Bay Area has been designated as an attainment area for the CO standards. The highest measured level in Concord (the closest monitoring station to the Project site) during the past three years is 1.24 ppm for eight-hour averaging periods

124 AIR QUALITY Even though current CO levels in the Bay Area are well below ambient air quality standards and there have been no exceedances of CO standards in the Bay Area since 1991, elevated levels of CO still warrant analysis. CO hotspots (occurrences of localized high CO concentrations) could still occur near busy congested intersections. Recognizing the relatively low CO concentrations experienced in the Bay Area, the BAAQMD s CEQA Air Quality Guidelines state that a project would have a less-than-significant impact if it would not increase traffic volumes at affected intersections to more than 44,000 vehicles per hour. The busiest intersections affected by traffic increases from the proposed Project would be along Ygnacio Valley Road, which would have total peak hour traffic volumes of less than 20,000 vehicles. Since intersections affected by the Project would have volumes less than the threshold of 44,000 vehicles per hour, the impact of the Project related to localized CO concentrations would therefore be less than significant. ii. Off-Site Community Risk and Hazards from Construction Activity The proposed Project could result in elevated concentrations of diesel particulate matter (DPM) and PM2.5 in the vicinity of sensitive land uses during construction activities. Sensitive land uses in the vicinity of the Project include residential areas to the south across Ygnacio Valley Road and to the west beyond Interstate 680. A construction risk assessment was conducted for DPM and PM2.5 generated by the Project pursuant to BAAQMD s guidance methodology. BAAQMD has developed screening thresholds for assessing potential health risks from construction activities. 28 For cancer risk and PM2.5 exposure, receptors would have to be located approximately 600 feet from the Project boundary to fall below BAAQMD s screening thresholds. The screening distance for chronic hazards is about 65 feet. There are no sensitive receptors within 65 feet of the proposed construction areas. Since receptors are located 28 Bay Area Air Quality Management District (BAAQMD)2010. Screening Tables for Air Toxics Evaluation During Construction

125 AIR QUALITY within 600 feet of the Project, a construction health risk assessment (HRA) was conducted to evaluate cancer risk and PM2.5 exposure. Construction sources evaluated in the HRA included off-road construction equipment (e.g. excavators, scrapers, loaders, bulldozers, backhoes, forklifts, and water trucks). In addition, on-road haul trucks, support vehicles (pickups), and workers commuting to the Project site were included in the evaluation. Using air dispersion models, exposure concentrations at sensitive receptors (both adult and child residents) were estimated. Excess lifetime cancer risks and acute and chronic non-cancer hazard indexes were calculated based on the mitigated construction scenario, with use of Diesel Particulate Filters (Level 2) for off-road equipment greater than 75 horsepower (hp). These risks were then compared to the significance thresholds identified in the BAAQMD CEQA Guidelines. Results of the HRA indicate that the incremental cancer risk for a sensitive receptor (child resident), to the south of the Project site during the construction period, based on the maximum concentration for a 70-year-lifetime, 24- hour outdoor exposure duration, is 9.3 x 10-6 (roughly 9 per million), which is less than the significance threshold of 10 per million. For non-carcinogenic effects, the hazard index identified for each toxicological endpoint totaled less than one. Therefore, acute and chronic non-carcinogenic hazards are within acceptable limits. In addition, PM2.5 annual concentrations are below the BAAQMD significance thresholds with mitigation incorporated. The results are summarized in Table The results of this HRA, with respect to community risk during the construction period, indicate that the Project impact would be less than significant with implementation of Mitigation Measure AQ-2 (listed below) requiring use of Diesel Particulate Filters (Level 2) for off-road equipment greater than 75 horsepower

126 AIR QUALITY TABLE MITIGATED CONSTRUCTION RISK SUMMARY OFF-SITE RECEPTORS Period Cancer Risk Child Cancer Risk Adult Chronic Hazard Acute Hazard PM2.5 Construction: x x BAAQMD Threshold 10 x x ug/m 3 Exceeds Threshold No No No No No Sources: ISCST3 air dispersion model. iii. On-Site Community Risk and Hazards In addition to construction-related health risks to the neighboring community, on-site health risks and hazards imposed by existing sources (e.g. stationary sources and traffic on adjacent streets and freeways) on the sensitive receptors of the Project (i.e. residents in the mixed-use rental apartments) were evaluated pursuant to BAAQMD s methodology. This analysis is provided for informational purposes only, but as described above, it is not required under CEQA. BAAQMD has developed screening thresholds for assessing potential health risks from stationary and mobile sources. Sources located within 1,000 feet of the proposed Project would be included in BAAQMD s screening thresholds. To evaluate nearby sources, BAAQMD s database of existing sources and freeway and surface street screening tables for Contra Costa County were used. Stationary sources near the Project site were identified using the BAAQMD Stationary Source Screening Analysis Tool. 29 A Risk and Hazard Stationary Source Inquiry Form was filled out to identify sources within 1,000 feet of 29 BAAQMD Stationary Source Screening Analysis Tool can be accessed from BAAQMD s website at Research/CEQA-GUIDELINES/Tools-and-Methodology.aspx

127 AIR QUALITY the Project site. This form was submitted to BAAQMD and they provided screening risk and hazard levels as well as screening multipliers to adjust risks from diesel engines and gasoline stations. This list is included in Appendix B3. Eight stationary sources were identified with emissions from emergency diesel generators and gasoline stations. For one source (the BART emergency diesel generator), BAAQMD provided emissions data used in the screening dispersion model to predict cancer risks from that source. According to BAAQMD records, the BART station includes a 475-horsepower generator. This generator is located in the center of the existing BART parking structure. The nearest residences for the proposed Project would be the Phase II residences about 190 feet north of the generator. The SCREEN3 model was used with default SCREEN3 screening methodology, BAAQMD default generator screening source parameters, and emissions based on BAAQMD inventory data. The effects of building downwash were included in the modeling. Cancer risk from this generator was computed at 0.2 excess chances per million. Modeling assumptions are included in Appendix B3 and a summary of the results for all stationary sources within 1,000 feet of the Project is provided in Table Mobile sources identified within 1,000 feet of the proposed Project include Interstate 680, Ygnacio Valley Road, North California Boulevard, and Main Street. Ygnacio Valley Road is a busy arterial roadway near the Project site with over 10,000 average daily traffic trips (ADT). According to the traffic analysis performed for the Project, there are almost 37,000 daily trips (twoway) adjacent to the Project site. The number of daily trips is anticipated to increase to almost 48,000 daily trips with approved projects and the proposed Project by Phase III residents would be about 70 feet or further from this roadway and Phase II residences would be over 500 feet away. North California Boulevard has about 15,000 daily trips and traffic is estimated to increase to almost 17,000 daily trips with the approved and the proposed Projects by The BAAQMD provides screening tables that indicate

128 AIR QUALITY TABLE ON-SITE COMMUNITY RISK SUMMARY Source Lifetime Cancer Risk a Chronic Hazard Acute Hazard PM2.5 California Plaza at Walnut Creek b Legacy Partners III b Xtra Oil Company b NA c Target Corporation # b Pacific Bell Corporation b USA Gas # b 0 SF BART District 0.20 d b SRS Development b Ygnacio Valley Rd e 7.3 <0.02 < North California Blvd e 0.7 <0.02 < Main Street e 0.2 <0.02 < I-680 f BAAQMD Individual Threshold 10 x ug/m 3 Exceeds Threshold Yes No No Yes a Lifetime cancer risk reported in excess cases per million, applying an age-sensitivity weighting factor to reflect the greater sensitivity of infants and small children to cancer causing TACs. b Acute Hazard Indexes for each stationary source within 1,000 feet of the Project were determined to be less than significant by BAAQMD and therefore not provided. c NA = Not Applicable. d Modeled using SCREEN3 and BAAQMD provided emissions data (Appendix B3). e Data obtained from BAAQMD Roadway Analysis Tables. f Data obtained from BAAQMD Google Earth Highway tool (Link 1079) interpolated at 120 feet. Sources: Air Quality and Health Risk Assessment (Illingworth & Rodkin, 2012 Appendix B3); SCREEN3 air dispersion model; BAAQMD,

129 AIR QUALITY predicted community risk impacts that roadways pose. 30 Interpolations of 50- and 100-foot screening risks from these tables indicate cancer risk would be less than 7.3 chances per million at Phase III residences and 1.4 per million at Phase II residences. Cancer risks from North California Street would be 1.4 per million or less at Phase II and III residences. Cancer risks from N. Main Street would be much lower. Table shows that the acute and chronic hazards would be well below the BAAQMD significance thresholds, for all stationary and mobile sources. The screening level cancer risk and PM2.5 concentration for Interstate 680 exceed the BAAQMD significance thresholds of 10 in a million and 0.30 µg/m 3. As described below, a risk assessment was conducted for emissions from Interstate 680 and bus operations from the relocated transfer area on the Project site. The proposed Project would place sensitive receptors near Interstate 680, a busy freeway with trucks and other vehicles that emit TACs. TAC emissions from Interstate 680 traffic include DPM emissions, organic TAC compounds, as well as fine particulate matter with a diameter of 2.5 microns or less or PM2.5, which is a regulated air pollutant. The health risk assessment considers local conditions such as source strength and meteorological conditions. The Project would include residential units approximately 120 feet or further from Interstate 680. Figure shows the proposed Transit Village and its proximity to Interstate 680. The residents closest to Interstate 680 would be those located in the westernmost portion of the Phase II development. In addition to TAC emissions from Interstate 680, transit buses serving the BART station traveling within the Transit Village area and accessing the new bus facility at the BART station are currently predominantly diesel fueled and would contribute to local DPM emissions in the Phase II and Phase III 30 BAAQMD Roadway Analysis Tables can be accessed from BAAQMD s website at GUIDELINES/Tools-and-Methodology.aspx

130 AIR QUALITY Phase II Phase I Phase III Source: Illingworth & Rodkin, Inc, FIGURE LOCATION OF TRANSIT VILLAGE RELATIVE TO INTERSTATE 680

131 AIR QUALITY residential areas of the Project. TAC emissions from on-site travel of local transit buses and emissions from Interstate 680 traffic were considered in this analysis. The BAAQMD CEQA Air Quality Guidelines consider exposure of sensitive receptors to air pollutant levels that result in an unacceptable cancer risk or hazard to be significant. For cancer risk, which is the main concern with diesel particulate matter, the BAAQMD considers an increased risk of contracting cancer that is 10 in 1 million chances or greater to be significant. In addition to the cancer risk from TACs, the BAAQMD considers that an incremental increase of PM2.5 of greater than 0.3 micrograms per cubic meter (μg/m 3 ) from a single source to cause significant adverse health effects. iv. Analysis of Site-Specific DPM Cancer Risk Future health risks from exposure to diesel particulate matter and other TACs emitted from Interstate 680 traffic and local bus service was predicted. Calculation of these health risks involves estimations of current and future vehicle emission rates, traffic levels, and dispersion modeling of emissions. Potential health risks were calculated at locations of the proposed residential units. Residential units will be in buildings of up to four stories within the Phase II and III development areas. These buildings would have mixed-use, commercial/retail and residential, on some of the lower levels, with residential units in the upper levels. Diesel particulate matter emissions from vehicles, particularly large diesel trucks and buses, are anticipated to decrease in the future. CARB has continually updated regulations and emission standards since identifying DPM as a carcinogen. CARB has adopted and implemented a number of regulations for stationary and mobile sources to reduce emissions of DPM. Several of these regulatory programs affect medium and heavy duty diesel trucks that represent the bulk of DPM emissions from California highways. These regulations include the fleet rule for transit agencies (affecting transit vehicles and urban buses), the solid waste collection vehicle (SWCV) rule, regulations affecting in-use public and utility fleets, and the heavy-duty diesel truck and bus regula

132 AIR QUALITY tions. Since this analysis assessed the risk of proposed residences to future exposures, the lower future emissions due to ongoing implementation of these regulations were factored into the model. This analysis involved development of future DPM and other TAC emissions for traffic on Interstate 680 and for the transit buses traveling within the Project site using the latest version of CARB s emission factor model (EM- FAC2011). The model was used with default vehicle information for Contra Costa County. DPM emissions are projected to decrease in the future due to state and federal vehicle emission standards and other CARB regulatory requirements. These emission reductions are reflected in the EMFAC2011 emissions data when evaluating emissions for future time periods. New CARB regulations require on-road diesel trucks to be retrofitted with particulate matter controls or replaced to meet new 2010 engine standards that have much lower DPM and PM2.5 emissions. This regulation will substantially reduce these emissions between 2013 and 2023, with the greatest reductions occurring between 2014 through While new trucks and buses will meet strict federal standards, this measure is intended to accelerate the rate at which the fleet either replaced by cleaner vehicles on the road or retrofitted to meet similar standards. With this regulation, older more polluting trucks would be removed from the roads much more quickly. CARB anticipates a 45 percent reduction in DPM emission from trucks in 2014 with this regulation. The requirements for diesel trucks, phased in for future years, depend on the model year of the trucks. Since this analysis assesses the risk of proposed residences to future exposures, the lower future emissions were taken into account. Emission factors were developed for 2017, the first year of occupancy, 2020, and 2025 using the EMFAC2011 model with default model vehicle fleet age distributions for Contra Costa County. The EMFAC2011 results were then adjusted based on the traffic volume and mix on Interstate 680 reported

133 AIR QUALITY by Caltrans. 31 Average daily traffic volumes were based on Caltrans data for Interstate 680 for 2010 and were increased by 0.4 percent per year to account for future traffic conditions. Average hourly traffic distributions for Contra Costa County freeways and roadways were developed using the EMFAC model, 32 which were then applied to the site-specific average daily traffic volumes to obtain hourly traffic volumes and emission projections for Interstate 680. An average freeway speed of 60 mph was used for all hours except two hours in the morning and evening peak periods. Average travel speeds of 35 mph in the morning and 50 mph in the evening for southbound traffic and the opposite pattern for northbound traffic were used for the peak periods, based on data from the Contra Costa Transportation Authority. 33 For the transit buses travelling through the Project site, DPM emissions were also calculated with the EMFAC2011 model using the urban bus emission factors for Contra Costa County. Although other transit systems serve the Walnut Creek BART Station, the predominant system is the CCCTA, so this service was reviewed in this Draft EIR. About 95 percent of the County s buses are diesel fueled buses and all of the County Connection diesel buses utilize particulate filters and have NOx controls. 34 Currently the average bus fleet age is about 9 years and by 2015 the average age of County Connection buses will be 2 to 3 years. Emissions were calculated for 2017 with EM- FAC2011 assuming the minimum model year for the buses was For future years beyond 2017, the emissions were assumed to be the same as 2017 since the County will continue to upgrade the bus fleet with newer low emitting buses in the future. There will be about 310 buses accessing the Project 31 Caltrans, based on 2010 Average Annual Daily Truck Traffic on the California State Highway System: 32 The Burden output from EMFAC2007, CARB s previous version of the EMFAC model, was used for this since the current web-based version of EMFAC2011 does not include Burden type output with hour by hour traffic volume information. 33 Contra Costa Transportation Authority, Draft 2011 Congestion Management Program Monitoring Report. 34 Personal communication with Scott Mitchell, County Connection Director of Maintenance, February 17,

134 AIR QUALITY site on a daily basis during the week, with fewer buses on weekends. Emissions were calculated for buses traveling along on-site bus routes while traveling to and from the proposed new bus facility. The buses were assumed to travel at an average speed of 15 mph within the site and 5 mph through the bus facility. Based on current operating conditions, buses were assumed to operate between 6:00 a.m. and 8:00 p.m. on a daily basis. This represents the time period when the majority of the buses are operating. Dispersion Modeling. Dispersion modeling was conducted using the EPA s ISCST3 dispersion model along with hourly meteorological data to calculate screening-level TAC concentrations at the locations of proposed residential units in the Project. The ISCST3 dispersion model is a BAAQMD recommended model for use in refined modeling analysis of CEQA projects. 35 The ISCST3 model calculates pollutant concentrations at receptors located in areas of flat or complex terrain from a variety of emission source types including point, area, volume, and line sources. The model was run using regulatory default dispersion options and urban dispersion coefficients due to the urban nature of the Project site and vicinity. Since there is some variation in terrain elevation between emission sources and receptor locations at the Project site the model was run using local terrain data obtained from USGS. In particular, terrain elevations were used since the section of Interstate 680 adjacent to the Project is elevated above the local terrain and due to minor variations in elevations within the Project site. The meteorological data used for the modeling was a four-year data set (2002 to 2005) of hourly meteorological data from the BAAQMD s monitoring station in Concord, California, which was obtained from the BAAQMD s website. The meteorological conditions at the monitoring station, located about 3 miles from the Project site, are reasonably representative of those at the Project site. Other inputs to the model included Project site geometry (based on site plans) and TAC and PM2.5 emission factors obtained from the EM- FAC2011 model. TAC and PM2.5 emissions from vehicles on Interstate 35 Bay Area Air Quality Management District (BAAQMD), Recommended Methods for Screening and Modeling Local Risks and Hazards. Version

135 AIR QUALITY 680 and from on-site bus trips the site were modeled as a series of line sources (i.e. volume sources along a path) representing the vehicle travel routes. Since the new bus facility will be located under the new parking structure it will only be open to the outside at the east and west ends of the facility. Therefore, emissions from the bus facility were modeled as volume sources located at the east and west bus facility structure openings. Since there will be multi-story residential units, each location of residential receptors was modeled at heights of 1.5, 4.6, 7.6, and 10.7 meters (5, 15, 25, and 35 feet) above ground level to assess the variation in TAC and PM2.5 concentrations with height. Cancer Risk. Using the modeled long-term average DPM and total organic gas concentrations, the individual cancer risks were computed using the most recent methods used by BAAQMD 36 and the California Office of Environmental Health Hazard Assessment (OEHHA) 37. The factors used to compute cancer risk is highly dependent on modeled concentrations, exposure period or duration, and the type of receptor. The exposure level is determined by the modeled concentration; however, it has to be averaged over a representative exposure period. The averaging period is dependent on many factors, but mostly the type of sensitive receptor that would reside at a site. This assessment assumed long-term residential exposures consistent with OEHHA assumptions and BAAQMD CEQA guidance. The increase in individual cancer risks for potential future residents at the Project site were computed from modeled TAC concentrations using the methods recommended by OEHHA for continuous exposure beginning in 2017 (the first year of occupancy for Phase II) for a 70-year lifetime exposure and a 30-year exposure. Consistent with BAAQMD guidance, residential exposure was assumed to be outdoors and continuous for Bay Area Air Quality Management District (BAAQMD), Air Toxics NSR Program Health Risk Screening Analysis (HSRA) Guidelines. 37 Office of Environmental Health Hazard Assessment (OEHHA), Air Toxics Hot Spots Program Risk Assessment Guidelines, Air Toxics Hot Spots Program Guidance Manual for Preparation of Health Risk Assessments

136 AIR QUALITY hours per day at a breathing rate of 302 liters per kilogram of body weight (L/kg-day). The cancer risk calculations reflect use of BAAQMD s most recent cancer risk calculation method, adopted in June The cancer risk calculations were based on applying age sensitivity weighting factors for each emissions period modeled to reflect the greater sensitivity of infants and small children to cancer causing TACs. Maximum increased cancer risks from Interstate 680 traffic were highest for the third story Phase II residential units, with the cancer risks to receptors at the first and second stories being slightly lower than those on the third story. The highest health risk would occur at the third story Phase II residential units closest to Interstate 680 in the building at the northwest portion of the Transit Village. Maximum increased cancer risks from on-site bus trips were highest for the first story Phase II residential units, with the cancer risks at the second, third, and fourth level receptors being lower than those of the first level units. The highest health risk from on-site bus travel would occur at the first level residential units closest to Interstate 680 in the building at the northwest portion of the Transit Village. This location has the highest number of buses passing by it. Table shows the variation in the maximum increased cancer risk from Interstate 680 traffic and from on-site bus travel with the Phase II residential floor stories at the location of maximum cancer risks. Increased cancer risks to residents at the Project site from mobile source TAC emissions range from 0.4 to 18.0 cancer cases per million for a 70- year exposure. The highest cancer risks would occur at the Phase II residential units in the building closest to Interstate 680. Table shows the maximum and cumulative increased cancer risk from Interstate traffic and from on-site bus travel for the Project for both 70- and 30-year exposure periods for the Phase II and Phase III residential developments. Over the course of a 70-year lifetime exposure, the incremental risk for the maximally exposed individual (MEI), representing the residential unit with the highest exposure to TACs from Interstate 680, is calculated at about 18.0 excess cancer cases per million people. Cancer risk at all other proposed residences would be less, because the TAC concentrations

137 AIR QUALITY TABLE VARIATION IN MAXIMUM CANCER RISK (PER MILLION) AT THE RECEPTOR LOCATION WITH THE HIGHEST OVERALL CANCER RISK FOR A 70-YEAR EXPOSURE Residential Floor Story (Phase II) First Receptor Height 5 feet (ground) Cancer Risk From I-680 Traffic Cancer Risk From On-Site Bus Travel Second 15 feet Third 25 feet Fourth 35 feet Source: Illingworth & Rodkin, TABLE MAXIMUM COMPUTED CANCER RISK FROM INTERSTATE 680 OR BUS TRAFFIC Source/Exposure Type I-680 Traffic Maximum Increased Cancer Risk (per million) Phase II Phase III Residences Residences 70-Year On-Site Exposure Year On-Site Exposure On-Site Bus Travel 70-Year On-Site Exposure Year On-Site Exposure Maximum Single Source (70-Year On-Site Exposure ) BAAQMD Single-Source Threshold 10.0 Exceeds Significance Threshold Yes No Source: Illingworth & Rodkin,

138 AIR QUALITY decrease further from the freeway and the freeway is the largest contributor to risk. The cancer risk for residences proposed in Phase III from any single source would all be under 10 in 1 million. Figure shows the maximum increased cancer risk from Interstate 680 traffic and on-site bus travel at each of the residential unit receptor locations at the Project site. Under the BAAQMD CEQA Guidelines, an incremental risk of greater than ten cases per million from a single emissions source at the Maximally Exposed Individual would result in a significant impact. Phase II of the Project would result in a lifetime cancer risk for the maximally exposed individual that would exceed 10 in 1 million. Although this is not an impact for purposes of CEQA purposes, as described above, the City considers this to be a significant impact that will be mitigated pursuant to Mitigation Measure AQ-3. Proposed residences in Phase III would have less-than-significant cancer risks. It should be noted that the standard exposure assumptions used in the risk assessment are very conservative. The incremental cancer risk is based on a continuous 70-year, 24-hour outdoor exposure, whereas the average period of US residency at any one location is approximately 9 years and the 90 th percentile of US residency (used by the USEPA as reasonable maximum exposure estimates) is 30 years. 38 The US Census Bureau indicates that the average person will move 11.7 times in a lifetime 39 and data collected for the Walnut Creek area show that 34 percent of the people in renter-occupied units moved within the 5-year period from 2006 to Studies also have indicated that the typical person spends approximately 87 percent of the time indoors, 5 percent outdoors, and 7 38 U.S. Environmental Protection Agency (USEPA), Handbook for Implementing the Supplemental Cancer Guidance at Waste and Cleanup Sites. Website: 39 US Census Bureau, Calculating Migration Expectancy Using ACS Data. Website: 40 US Census Bureau, Geographic Mobility by Selected Characteristics for Walnut Creek City, California. Website: factfinder2.census.gov/

139 AIR QUALITY Excess Health Risk Zone Excess Health Risk from Interstate 680 Traffic Excess Health Risk From On-Site Bus Travel Source: Illingworth & Rodkin, Inc, FIGURE MAXIMUM INCREASED CANCER RISK FOR 70-YEAR EXPOSURE AT TRANSIT VILLAGE RECEPTOR LOCATIONS

140 AIR QUALITY percent of the time in vehicles. 41 Indoor air concentrations will be lower than outdoor air concentrations, resulting in a lower incremental cancer risk than was calculated. In addition, the California diesel reduction program will result in cleaner burning diesel engines and emission controls, resulting in further reductions in DPM and lower estimated cancer risks. With implementation of the mitigation measures proposed in Section F of this chapter, including Mitigation Measures AQ-1 and AQ-2, which require compliance with BAAQMD BMPs for reducing construction emissions, and Mitigation Measure AQ-3, which requires the installation in Phase II buildings of air filters or a ventilation system capable of at least 65 percent of the DPM/PM2.5, the incremental cancer risk for all receptors at the Project site would be less than significant. Potential non-cancer health effects due to chronic exposure to DPM were not estimated since the concentration threshold for non-cancer effects is considerably higher than concentrations that would result in significant cancer risks that were described above. The chronic inhalation reference exposure level (REL) for DPM is 5 µg/m 3. The maximum predicted annual DPM exposure is 0.04 µg/m 3. Thus, the Hazard Index (HI), which is the annual DPM concentration divided by the REL, would be 0.008, which is much less than the HI significance criterion of 1.0. PM2.5. In addition to evaluating the health risks from TACs, potential impacts from PM2.5 emissions from vehicles traveling on Interstate 680 and on-site bus travel were evaluated. The BAAQMD has adopted a significance threshold of an annual average PM2.5 concentration greater than 0.3 µg/m 3. The same basic modeling and analysis approach that was used for assessing TAC impacts was used in the modeling of PM2.5 concentrations from Interstate 680 and from on-site bus travel. PM2.5 emissions from all vehicles traveling on Interstate 680 were used, because both gasoline and 41 U.S. Environmental Protection Agency (USEPA), National Human Activity Pattern Survey (NHAPS): A Resource for Assessing Exposure to Environmental Pollutants

141 AIR QUALITY diesel powered vehicles produce PM2.5. As discussed previously, BAAQMD screening tools were used to assess the significance of PM2.5 exposure from local roadways and stationary sources. The PM2.5 concentrations were below BAAQMD significance thresholds for local roadways and stationary sources. The maximum annual average PM2.5 concentrations for emissions from Interstate 680 and on-site bus travel was found to occur at the same locations as the maximum DPM concentrations at the Project site. Table summarizes the maximum-modeled annual average PM2.5 concentrations in the Phase II and Phase III residential areas for Interstate 680 traffic and for on-site bus travel. The highest average annual modeled concentration from Interstate 680 was 0.08 µg/m 3. Concentrations at all other receptor locations in the Project site would be less than this highest value. Since annual PM2.5 concentrations are not predicted to exceed 0.3 µg/m 3 from any single source, the impact associated with PM2.5 exposure would be less than significant. BAAQMD has also identified thresholds for exposure to cumulative sources. These would be a combination of busy roadways or stationary sources located within 1,000 feet of the Project site. The contributions of these cumulative sources at Phase II and Phase III areas are also shown in Tables and The cancer risk caused by the cumulative source would be well below the threshold of 100 excess cancer cases per million identified by BAAQMD. The cumulative PM2.5 annual concentrations at each location would also be below the threshold of 0.8 µg/m 3 identified by BAAQMD. d. Would the Project create or expose a substantial number of people to objectionable odors? Odors are assessed based on the potential of the proposed Project to result in odor complaints. This could result by the proposed Project creating objectionable odors or placing people near sources of objectionable odors. There could be temporary odors generated by construction activities, but these are not expected to cause objectionable odors. The Project would

142 AIR QUALITY TABLE MAXIMUM PM2.5 CONCENTRATIONS Maximum Increased PM2.5 Concentrations (μg/m 3 ) Phase II Phase III Source/Exposure Type Residences Residences I-680 Traffic On-Site Bus Travel 0.01 <0.01 BAAQMD Single-Source Threshold 0.3 Exceeds BAAQMD Threshold No No Source: Illingworth & Rodkin, 2012 and BAAQMD, include a mix of uses that could place new residences near localized sources of odors. An example would be the Phase III mixed-use building that includes residences and restaurants. While this mix of uses is common in urban areas, odor complaints can occur. Some people find odors from restaurants objectionable, while others find them pleasant. In some cases, restaurant cooking odors have resulted in complaints. However, any new restaurants in the mixed-use buildings will be designed to ensure that kitchen exhaust ventilation systems are installed in accordance with the California Retail Food Code (Health & Safety Code sec et seq.) and other applicable regulations. Therefore, the Project would have a less than significant impact because it would not create substantial objectionable odors affecting a substantial number of people. e. Would the Project conflict or obstruct implementation of the applicable air quality plan? The BAAQMD is the regional agency responsible for overseeing compliance with State and federal laws, regulations, and programs within the SFBAAB. The BAAQMD, with assistance from ABAG and MTC, has prepared and implements plans to meet the applicable laws, regulations, and programs. The most recent air quality management plan is the Bay Area 2010 Clean Air

143 AIR QUALITY Plan. 42 In formulating compliance strategies, BAAQMD relies on planned land uses established by local general plans. Land use planning affects vehicle travel, which in turn affects region wide emissions of air pollutants and GHG. The proposed Project would require a General Plan Amendment to change the land use designations for the Project site. The General Plan 2025 designates the west side of the proposed Project site (west of the BART tracks) as Mixed-Use Residential and the east side as Public/Semi-Public. This is because development of only the western portion of the site was under consideration at the time the General Plan update process in A General Plan amendment is proposed to expand the mixed-use designation to the eastern portion of the site. Although the amendment to the General Plan would change land use assumptions built into the Clean Air Plan, the projected growth caused by the Project would not exceed the amount of growth projected under the City s 2025 General Plan. Please refer to Chapter 4.9 of this EIR for additional discussion of Project population growth in relation to General Plan 2025 and ABAG growth Projections. Furthermore, the Project is not expected to cause an increase in population or substantially affect the rate of regional vehicle miles traveled (VMT) growth in a manner that would be inconsistent with regional clean air planning efforts. Vehicle trips generated from the Project are projected to be lower than traditional development in Walnut Creek due to the proximity to regional transit and on-site commercial uses. In addition, the City s General Plan 2025 EIR found that the General Plan policies include transportation control measures (TCMs) consistent with those identified in the 2005 Clean Air Plan prepared by BAAQMD, ABAG, and MTC, which are consistent with those contained in the current 2010 Clean Air Plan. The proposed Project would support, rather than hinder, implementation of the air quality control measures included in the latest 42 Bay Area Air Quality Management District (BAAQMD), Bay Area 2010 Clean Air Plan

144 AIR QUALITY Clean Air Plan by, for example, including elements that enhance transit, bicycle, and pedestrian modes of transportation. One of the key principles of these regional planning goals is to increase the amount of housing in urbanized parts of the Bay Area, in order to accommodate the region s residential demand. The proposed Project would provide high-density housing in an urbanized part of the Bay Area that is directly served by local and regional transit and has a mix of land uses to promote walking and bicycling. The proposed Project would include features and implementing measures that are consistent with Clean Air Plan control measures. The proposed Project would result in a less-than-significant impact with respect to Clean Air Plan consistency. E. Cumulative Impacts This section analyzes potential impacts related to air quality that could occur from a combination of the proposed Project with other past, present, and reasonably foreseeable projects within the SFBAAB. Any project that produces a significant project-level regional air quality impact in an area that is in nonattainment adds to the cumulative impact. Due to the extent of the area potentially impacted from cumulative project emissions (the air basin), a project is cumulatively significant when project-related emissions exceed the BAAQMD emissions thresholds shown in Table As described above, the proposed Project would have construction and operational emissions that are less than the BAAQMD emission thresholds. In addition, CO hotspots associated with Project operation would be below BAAQMD screening thresholds and also would be cumulatively less than significant. With respect to community risk and hazards, a project would have a cumulative considerable impact if the aggregate total of all past, present, and foreseeable future sources within a 1,000-foot radius from the fence line of a source, or from the location of a receptor, plus the contribution from the Project, exceeds the following:

145 AIR QUALITY Non-compliance with a qualified risk reduction plan; or An excess cancer risk levels of more than 100 in one million or a chronic non-cancer hazard index (from all local sources) greater than 10.0; or 0.8 μg/m3 annual average PM2.5. On-site health risk assessment results are shown in Table and indicate that the cumulative cancer risk for a resident of the Project due to the combined impact of all stationary and mobile sources within 1,000 feet of the Project, based on the maximum ground-level concentration for a 70-year, 24-hour outdoor exposure duration, is 43 x 10-6 (roughly 43 per million), which is less than the significance threshold of 100 per million for cumulative source screening. In addition, PM2.5 annual 1-hour concentrations are below the BAAQMD cumulative significance thresholds. Therefore, the Project s onsite cumulative air quality impacts due to stationary and mobile sources with respect to on-site risk and hazards would be less than significant. F. Impacts and Mitigation Measures With the implementation of Mitigation Measures AQ-1 through AQ-4, the Project would not result in any significant project-specific or cumulative impacts with respect to air quality. Impact AQ-1: Project demolition and construction activities could generate fugitive dust, specifically PM10. Though these emissions would not exceed BAAQMD standards, BAAQMD nonetheless recommends, and the City requires, that all proposed projects implement BAAQMD s Basic Control Measures for fugitive dust control during construction. Mitigation Measure AQ-1: The Project shall comply with the following BAAQMD Best Management Practices (BMPs) for reducing construction emissions:

146 AIR QUALITY TABLE ON-SITE CUMULATIVE COMMUNITY RISK SUMMARY Source Cancer Risk PM2.5 Interstate On-Site Bus Traffic Ygnacio Valley Road North California Blvd Main Street Stationary Sources Sum of All Sources BAAQMD Cumulative Threshold 100E Exceeds Threshold No No *Actual risks and PM2.5 concentrations are less than these values, because the highest MEI number was used in this table for each source whereas the MEI will vary depending on location relative to the sources. Source: Illingworth & Rodkin, All exposed surfaces (e.g. parking areas, staging areas, soil piles, graded areas, and unpaved access roads) shall be watered two times per day. 2. All haul trucks transporting soil, sand, or other loose material off-site shall be covered. 3. All visible mud or dirt track-out onto adjacent public roads shall be removed using wet power vacuum street sweepers at least once per day. The use of dry power sweeping is prohibited. 4. All vehicle speeds on unpaved roads shall be limited to 15 mph

147 AIR QUALITY 5. All roadways, driveways, and sidewalks to be paved shall be completed as soon as possible. Building pads shall be laid as soon as possible after grading unless seeding or soil binders are used. 6. Idling times shall be minimized either by shutting equipment off when not in use or reducing the maximum idling time to 5 minutes (as required by the California airborne toxics control measure Title 13, Section 2485 of California Code of Regulations [CCR]). Clear signage shall be provided for construction workers at all access points. 7. All construction equipment shall be maintained and properly tuned in accordance with manufacturer s specifications. All equipment shall be checked by a certified mechanic and determined to be running in proper condition prior to operation. 8. Construction equipment shall not be staged adjacent to existing residences or sensitive receptors. 9. A publicly visible sign with the telephone number and person to contact at the Lead Agency regarding dust complaints will be posted. This person shall respond and take corrective action within 48 hours. The Air District s phone number shall also be visible to ensure compliance with applicable regulations. Significance after Mitigation: Adherence to the BAAQMD Basic Control Measures for reducing construction emissions of PM10 and PM2.5 would ensure that ground-disturbing activities would not generate a significant amount of fugitive dust. There would be a less than significant impact in this regard. Impact AQ-2: Use of heavy off-road and on-road construction equipment would produce substantial emissions of TACs and PM2.5, which would exceed the BAAQMD off-site community risk and hazards threshold of significance. This would be a significant impact

148 AIR QUALITY Mitigation Measure AQ-2: The construction contractor shall implement the following measures to reduce construction exhaust emissions during grading and construction activities: The construction contractors shall use Level 2 Diesel Particulate Filters for construction equipment over 75 horsepower. A list of construction equipment by type and model year shall be maintained by the construction contractor onsite. The construction contractor shall ensure that all construction equipment is properly serviced and maintained to the manufacturer s standards to reduce operational emissions. The construction contractor shall limit nonessential idling of construction equipment to no more than five consecutive minutes. Significance after Mitigation: Use of diesel particulate filters as required by Mitigation Measure AQ-2, would reduce TAC and PM2.5 below BAAQMD s off-site community risk and hazard levels. As shown in Table 4.2-7, the impact would be reduced to a less-than-significant level. Impact AQ-3: Operation of the Project would expose sensitive receptors residing in Phase II of the Project to unhealthy levels of TACs, particularly DPM, emitted by vehicle traffic on Interstate 680 adjacent to the Project site. This would result in a significant impact. Mitigation Measure AQ-3: For those residential units where the cancer risk is predicted to be in excess of the threshold, the applicant shall install Minimum Efficiency Reporting Value (MERV) filters with a rating sufficient to achieve compliance with the BAAQMD threshold for each unit or install a filtration system that achieves an equivalent percent reduction in particulate concentrations. MERV 11 filters have a particle size removal efficiency that results in a 65 percent to 80 percent reduction of particulates in the 1.0 to 3.0 micron range and will be required for those units where the cancer risk is the greatest. Assuming installation of a

149 AIR QUALITY MERV-11 filter system that removes at least 65 percent of the DPM/PM2.5 inside of residential units and an outdoor exposure of 3 hours per day for residents, the excess cancer risk for the maximum exposed individual (MEI) would be reduced from 18 in a million to 7.8 in a million. Prior to final Project approval, a filtration system shall be specified that will reduce DPM/PM2.5 concentrations at each residential unit where the cancer risk is predicted to be significant (i.e. above 10 in a million). Because the air quality study was intended as a worst case analysis and a more refined analysis that includes more detailed Project design, such as unit locations, ventilation, and more accurate move-in date, may find that a different number units will require such filtration (or different filtration), this measure may be refined if, prior issuance of building permits, the Project Applicant conducts a subsequent refined evaluation of air quality and air filtration system specifications and demonstrates that an alternative air filtration system or its application to a different number of residential units would continue to ensure that health risks remain below the thresholds set forth by the BAAQMD or the City with regard to exposure to toxic air contaminants. To ensure long-term maintenance and replacement of the MERV filters in the residential units, the owner/property manager shall maintain and replace the filters in accordance with the manufacturer s recommendations. The rental representative shall also provide notification to all affected tenants of the potential health risk from Interstate 680 and shall inform renters of increased exposure to DPM from Interstate 680 when the windows are open. Significance After Mitigation: Less-than-significant. Use of MERV filters with a rating of 11 or equivalent filtration system will reduce DPM/PM2.5 concentrations up to 65 percent. With implementation of this measure, the impact of vehicle traffic along Interstate 680 will be less than significant

150 AIR QUALITY

151 4.3 CULTURAL RESOURCES This chapter describes the regulatory framework and existing conditions on the Project site related to cultural resources, and the potential impacts of the Project on cultural resources. Cultural resources include historically and architecturally significant resources, as well as archaeological and paleontological resources. A. Regulatory Framework This section described the policies and regulations that apply to cultural resources in Walnut Creek. 1. Federal Regulations a. National Historic Preservation Act The National Historic Preservation Act of 1966 established the National Register of Historic Places (National Register) as the official designation of historical resources, including districts, sites, buildings, structures, and objects. For a property to be eligible for listing in the National Register, it must be significant in American history, architecture, archaeology, engineering, or culture, and must retain integrity in terms of location, design, setting, materials, workmanship, feeling, and association. Resources less than 50 years in age, unless of exceptional importance, are not eligible for the National Register. Though a listing in the National Register does not prohibit demolition or alteration of a property, CEQA requires the evaluation of project effects on properties that are listed in the National Register. 2. State Regulations a. The California Environmental Quality Act (CEQA) Section of the CEQA Guidelines states that a project that may cause a substantial adverse change in the significance of a historical resource is a project that may have a significant effect on the environment. The CEQA Guidelines define four ways that a property can qualify as a historical resource for purposes of CEQA compliance: 4.3-1

152 CULTURAL RESOURCES The resource is listed in or determined eligible for listing in the California Register of Historical Resources, as determined by the State Historical Resources Commission. The resource is included in a local register of historical resources, as defined in Section (k) of the Public Resources Code, or identified as significant in a historical resource survey meeting the requirements of Section (g) of the Public Resources Code, unless the preponderance of evidence demonstrates that it is not historically or culturally significant. The lead agency determines the resource to be significant in the architectural, engineering, scientific, economic, agricultural, educational, social, political, military, or cultural annals of California, as supported by substantial evidence in light of the whole record. The lead agency determines that the resource may be a historical resource as defined in Public Resources Code Sections (j) or (CEQA Guidelines Section ) which means, in part, that it may be eligible for the California Register. In addition, Public Resources Code Section and Section of the CEQA Guidelines specify lead agency responsibilities to determine whether a project may have a significant effect on archaeological resources. If it can be demonstrated that a project will damage a unique archaeological resource, the lead agency may require reasonable efforts for the resources to be preserved in place or left in an undisturbed state. Preservation in place is the preferred approach to mitigation. The Public Resources Code also details required mitigation if unique archaeological resources are not preserved in place. Section of the CEQA Guidelines specifies procedures to be used in the event of an unexpected discovery of Native American human remains on non-federal land. These provisions protect such remains from disturbance, vandalism, and inadvertent destruction, establish procedures to be implemented if Native American skeletal remains are discovered during construc

153 CULTURAL RESOURCES tion of a project, and establish the Native American Heritage Commission (NAHC) as the authority to identify the most likely descendant and mediate any disputes regarding disposition of such remains. b. California Register of Historic Resources (California Register) The California Register establishes a list of properties to be protected from substantial adverse change (Public Resources Code Section ). The State Office of Historic Preservation (OHP) has determined that buildings, structures and objects 45 years or older may be of historical value. A historical resource may be listed in the California Register if it meets any of the following criteria. It is associated with events that have made a significant contribution to the broad patterns of California s history and cultural heritage. It is associated with the lives of persons important in California s past. It embodies the distinctive characteristics of a type, period, region, or method of construction, or represents the work of an important creative individual, or possesses high artistic value. It has yielded or is likely to yield information important in prehistory or history. The California Register includes properties that are listed or have been formally determined eligible for listing in the National Register, State Historical Landmarks and eligible Points of Historical Interest. Other resources that may be eligible for the California Register, and which require nomination and approval for listing by the State Historic Resources Commission, include resources contributing to the significance of a local historic district, individual historical resources, historical resources identified in historic surveys conducted in accordance with OHP procedures, historic resources or districts designated under a local ordinance consistent with the procedures of the State Historic Resources Commission, and local landmarks or historic properties designated under local ordinance

154 CULTURAL RESOURCES Additionally, for a resource to be eligible for the California Register of Historic Resources, it must retain sufficient integrity to be recognizable as a historical resource and to convey its significance. c. Title 14, Penal Code, Section 622 ½ According to Penal Code Section 622 ½, anyone (except the owner) who willfully damages or destroys an item of archaeological or historic interest or value is guilty of a misdemeanor. d California Historical Building Code, California Code of Regulations, Title 24, Part 8 The California Historical Building Code (CHBC) (as set forth in Sections to of Division 13, Part 2.7 of Health and Safety Code and as subject to the rules and regulations set forth in 24 CCR Part 8), provides regulations and standards for the rehabilitation, preservation, restoration (including related reconstruction) or relocation of historical buildings, structures, and properties deemed by any level of government as having importance to the history, architecture, or culture of an area. The City of Walnut Creek has adopted the 2010 CHBC as part of its Municipal Code. e. Health and Safety Code Section 7052 and Section 7052 of the Health and Safety Code states that the disinterment of remains known to be human, without authority of law, is a felony. Section requires that construction or excavation be stopped in the vicinity of discovered human remains until the county coroner can determine whether the remains are those of a Native American. If determined to be Native American, the coroner must contact the NAHC. f. California State Senate Bill 18 Senate Bill (SB) 18, which went into effect January 1, 2005, set forth requirements for local governments (cities and counties) to consult with Native American tribes to aid in the protection of traditional tribal cultural places 4.3-4

155 CULTURAL RESOURCES through local land use planning. 1 The intent of SB 18 is to provide California Native American tribes an opportunity to participate in local land use decisions at an early stage of planning for the purpose of protecting, or mitigating impacts to, cultural places. The purpose of involving tribes at these early planning stages is to allow consideration of cultural places in the context of broad local land use policy prior to individual site-specific, project level land use designations are made by a local government. g. Public Resources Code Section 5097 Public Resources Code Section 5097 specifies the procedures to be followed in the event of the unexpected discovery of human remains on non-federal public lands. The disposition of Native American burials fall within the jurisdiction of the NAHC, which prohibits willfully damaging any historical, archaeological, or vertebrate paleontological site or feature on public lands. 3. Local Regulations a. Walnut Creek General Plan 2025 The Walnut Creek General Plan 2025 Built Environment chapter contains the following goals, policies, and actions related to the protection of cultural resources. These policies require records searches for development projects recognizing the potential for discovery of archaeological resources, and call for preservation, restoration, and compatible reuse of historically significant structures and sites. GOAL 16. Maintain and enhance Walnut Creek s identity and sense of place. Policy Foster the preservation, restoration, and compatible reuse of architecturally significant structures and sites. Action Develop an inventory and map of architecturally significant properties and landmarks. 1 SB 18 amends Government Sections (GC) , 65092, and 65560, while adding GC sections , and

156 CULTURAL RESOURCES GOAL 24. Protect and conserve archaeological and paleontological resources. Policy Review the potential for the presence of archaeological and paleontological resources and remains in or near identified archaeological sites. Action Require (a) review by the California Archaeological Inventory, Northeast Information Center, Sonoma State University, of all major new projects and all projects of any size within 660 feet of a site identified on the City s map of sensitive archaeological sites, and (b) add appropriate mitigations as conditions of project approval as may be recommended by the California Archaeological Inventory. Action Require developers to halt all work if cultural resources are encountered during a project, and to retain a qualified archaeologist to evaluate and make recommendations for conservation and mitigation. GOAL 25. Maintain and enhance Walnut Creek s historic resources. Policy Foster the preservation, restoration, and compatible reuse of historically significant structures and sites. Action Develop an inventory and map of historically significant properties. Action Develop a historic preservation plan and supporting ordinances

157 CULTURAL RESOURCES B. Existing Conditions This section provides an overview of the history of Walnut Creek and of resources of historical significance that may be affected by the proposed Project. 1. Paleontological Resources Paleontological resources (fossils) are the remains and/or traces of prehistoric plant and animal life exclusive of human remains or artifacts. Fossil remains such as bones, teeth, shells, and wood are found in the geologic deposits (rock formations) in which they were originally buried. Paleontological resources represent a limited, non-renewable, sensitive scientific and educational resource. The potential for fossil remains at a location can be predicted through previous correlations that have been established between the fossil occurrence and the geologic formations within which they are buried. For this reason, knowledge of the geology of a particular area and the paleontological resource sensitivity of particular rock formations, make it possible to predict where fossils will or will not be encountered. A search of the University of California Museum of Paleontology Specimen Search database indicated that there are no known resources within the City of Walnut Creek. 2 The closest recorded paleontological specimens are located in Mount Diablo State Park, approximately 10 miles to the east of the Project site. 2. Archaelogical Resources Archaeological investigations in and around Walnut Creek indicate a period of continuous habitation lasting nearly 4,000 years, from possibly 2000 BC to 1700 AD. 3 In the late prehistoric and early historic periods, the San Francisco 2 University of California Museum of Paleontology, Specimen Search, accessed on October 20, Fredrickson, D.A., Changes in Prehistoric Exchange Systems in the Alamo Locality, Contra Costa County, California. In Toward a new Taxonomic Framework for Central California Archaeology: Essays by James A. Bennyhoff and David A

158 CULTURAL RESOURCES Bay area was occupied by scores of small, independent Native American tribelets belonging to five language groups. The Bay Miwok people occupied eastern Contra Costa County north of Mount Diablo, from around Walnut Creek east to the Sacramento-San Joaquin Delta. Circa 1776, it is estimated that approximately 1,700 Bay Miwok inhabited the whole of this territory. 4 A Bay Miwok tribelet was centered along San Ramon Creek west of Mount Diablo, and may have had their central village in the Walnut Creek area. Each tribelet was an independent and sovereign nation of 200 to 400 people that controlled a defined territory 8 to 12 square miles in area, and which contained a number of families in several more or less permanently inhabited villages. The Bay Miwok believed that Mount Diablo was a sacred place, and the mountain was featured prominently in their mythology. Prehistoric archaeological resources in the Walnut Creek area include habitation sites, burial sites and burial mounds, lithic scatters, shell middens, shell and earth middens, bedrock mortars, and cupule boulders. Typically, these sites are located in stream valleys, including those of Walnut Creek, Las Trampas Creek, Tice Creek, and San Ramon Creek. A records and literature search performed at the Northwest Information Center of the California Historical Resources Information System (CHRIS) for the General Plan 2025 included a review of maps, records, National Register listings, the State of California Historic Landmarks register and county and city registers for historic sites. The search revealed that 15 prehistoric cultural resource sites have been recorded and that another two sites have been identified, but not officially recorded within present day Walnut Creek city limits. The specific locations of these archaeological sites are recorded in CHRIS, but are kept confidential to prevent looting or vandalism of the sites. The Project is located in an area considered highly sensitive for archaeological resources, as shown in Figure Fredrickson, assembled and edited by R.E. Hughes, pages Contributions of the University of California Archaeological Research Facility, No. 52, Berkeley. 4 Levy, R. Eastern Miwok Handbook of North American Indians, Volume 8 (Washington, D.C.: Smithsonian Institution, 1978), pages

159 Buena Vista Ave CITY OF WALNUT CREEK CULTURAL RESOURCES Pleasant Hill Concord BART Treat Blvd Oak Grove Rd Bancroft Rd Geary Road N Main St Ygnacio Valley Rd Boundary Oak Lime Ridge Open Space I-680 Civic Dr Proposed Project Site Heather Farm Walnut Ave Castle Rock Rd BART Hwy 24 Lafayette Walnut Blvd Shell Ridge Open Space Olympic Blvd Rudgear Rd Tice Valley Blvd I-680 Rossmoor Pkwy Low Sensitivity Moderate Sensitivity High Sensitivity Highways Major Roads City Limit Planning Area Boundary Creek Miles NORTH Mile Base Map Data: January 16, 2004 Source: Walnut Creek General Plan 2025 EIR Alamo Note: The boundaries of the sensitivity areas are based on hand-edited maps prepared by Stephen Byrne, M.S., RPA, of Garcia and Associates, San Anselmo. The sensitivity area boundaries correspond to a variety of elevation levels, ridge lines, urbanization edges, and jurisdictional boundaries depicted on the following USGS 7.5' quadrangle maps used: Walnut Creek (1995), Las Trampas Ridge (1980), and Clayton (1994). FIGURE ARCHAEOLOGICALLY SENSITIVE AREAS

160 CULTURAL RESOURCES 3. Historical Resources a. Local Historical Context In 1772, the Spanish began exploring the inner coastal region of California. The Bay Miwok were the first of the Eastern Miwok to undergo missionization, with the first recorded Bay Miwok converts coming from the Saclan tribelet to Mission San Francisco in The first baptisms of Bay Miwok occurred between 1805 and Many Bay Miwok tribelets later disappeared due to the combined effects of missionization and epidemics, which killed thousands in the first half of the nineteenth century. 7 When Mexico became independent from Spain in 1822, the Spanish missions were secularized and their lands redistributed to private individuals by way of land grants. Large parcels were developed into cattle ranches maintained by Mexican grantees. Four land grants were awarded in the Walnut Creek area: Rancho San Ramon (1826), Rancho Arroyo de las Nueces y Bolbones (1834), Rancho Cañada del Hambre (1842) and Rancho Las Juntas (1844). 8 These four grants converged at what later became downtown Walnut Creek. Lands around the Project site were part of Rancho Las Juntas, which encompassed the area west of downtown Walnut Creek. 9 The first European settlement in present day Walnut Creek was established in 1849, during the California Gold Rush. Settlement continued with the admission of California into the Union in 1850, and in 1862, a US Post Office 5 Levy, R. Eastern Miwok in Handbook of North American Indians, Volume 8 (Washington, D.C.: Smithsonian Institution, 1978, page Levy, R. Eastern Miwok in Handbook of North American Indians, Volume 8 (Washington, D.C.: Smithsonian Institution, 1978, page Levy, R. Eastern Miwok in Handbook of North American Indians, Volume 8 (Washington, D.C.: Smithsonian Institution, 1978, page Rovanpera, Brad, Years in Pictures: An Illustrated History of Walnut Creek (Carlsbad, California: Heritage Media Corporation), page Emanuels, George, 1984, Walnut Creek Arroyo de las Nueces, Walnut Creek, California: Self published

161 CULTURAL RESOURCES was established and the community was named Walnut Creek. 10 The first trains arrived in Walnut Creek in In 1909, the Oakland & Antioch Railway Company built a commuter line and by 1913, there was electrified interurban service between Walnut Creek and Oakland. 12 In 1937, the new Caldecott Tunnel officially opened, allowing quicker and easier trips between Walnut Creek and Oakland. A year earlier, the San Francisco-Oakland Bay Bridge had been completed, allowing motorists to drive directly to San Francisco without having to transfer to a ferry in Oakland. By 1941, however, regular Oakland-Walnut Creek commuter rail service had ended. 13 Walnut Creek s population boomed after the Second World War, spurred by the same factors that propelled suburban growth nationally. Farmland surrounding the old village was developed as tract houses, shopping centers and highways. The city s location at the junction of two major highways, Highway 24 and Highway 21 (later Interstate 680), made it an ideal location for retail development. Rail links with Oakland and San Francisco once again accompanied growth, and in 1973 the Bay Area Rapid Transit (BART) Concord Line was extended to Walnut Creek, reestablishing commuter rail service. 14 Between 1975 and 1985, over 6.5 million square feet of new commer- 10 City of Walnut Creek website history/timeline.asp. 11 City of Walnut Creek website history/timeline.asp. 12 City of Walnut Creek, California, Forging the Future Yesterday & Today (Walnut Creek, California Golden Anniversary ), by Fred A. Sanders, mayor, Newell B. Case, Francis X. Driscoll, Douglas R. Page, Robert I Schroder, Councilmen anonymous. 13 Emanuels, George, Ygnacio Valley Walnut Creek, California. Self published, page BART Chronology. Website history.pdf accessed April 10,

162 CULTURAL RESOURCES cial space was constructed in Walnut Creek, much of it around the BART station. 15 b. Federally and State Recognized Historic Resources The Project site is currently almost entirely built out, containing the Walnut Creek BART station and associated parking facilities and roadways. The oldest structure on the Project site is the station building, which dates from Development in the vicinity of Project site includes office towers constructed in the 1970s and 1980s to the north, and office buildings constructed more recently to the east of the site. To the south, across Ygnacio Valley Road, there are retail and residential buildings generally constructed in the last 30 years. None of the structures on or adjacent to the Project site are listed on either the National Register or the California Register. The National Register requires that buildings be 50 years or older prior to eligibility for listing (unless they are determined to be of exceptional importance), while the State Office of Historic Preservation (OHP) has determined that buildings, structures and objects 45 years or older may be of historical value and therefore eligible for inclusion on the California Register. As such, given the age of buildings and structures on and adjacent to the Project site, there are no structures likely to be eligible for inclusion on the National Register or the California Register. c. Locally Recognized Historic Resources Using baseline information from an inventory of historic resources sponsored by the Contra Costa County Planning Department in 1975, the City of Walnut Creek has developed a list of historic and potentially historic buildings within its jurisdiction. As shown in Figure 4.3-2, there are two potentially historic buildings in proximity to the Project site: Stan s Brick House 15 Rovanpera, Brad, Walnut Creek: A Look Back, pictorial chronicle compiled for the City of Walnut Creek, page

163 I-680 CITY OF WALNUT CREEK CULTURAL RESOURCES I-680 Buena Vista Ave 2 1 Lafayette Proposed Project Site Civic Dr Ygnacio Valley Rd 3 Walnut Blvd Hwy Olympic Blvd Potentially Historic Sites 1. Stan s Brick House (Le Virage Restaurant) 2. Howard Residence 3. Chapel, St. Paul s Episcopal Church 4. Leech Home and Office 5. Women s Club of Walnut Creek Building 6. Old Fire Station (Havana Restaurant) 7. Valley Mercantile 8. Lawrence Meat Company 9. Dr. Eckley s (Tudor Architecture) 10. Schroder Insurance Company 11. California Water Service Company 12. Old Mortuary (Crogans) 13. Christian Science Church 14. Rogers Hotel 15. Dole House 16. Masonic Temple (Home Chef) 17. First Commercial Building (La Fogata) 18. Veterans' Memorial Building 19. Walnut Creek Southern Pacific Depot 20. Marshall Residence 21. Casa Christina Alamo Highways Major Roads City Limit Planning Area Boundary 20 Miles NORTH Miles Base Map Data: January 16, 2004 Source: Walnut Creek General Plan 2025 EIR FIGURE POTENTIALLY HISTORIC RESOURCES Miles

164 CULTURAL RESOURCES (formerly Le Virage Restaurant), located at 2211 North Main Street, and St. Paul s Episcopal Church, located at 1924 Trinity Avenue, approximately one block south of the Walnut Creek BART station. C. Standards of Significance The proposed Project would result in a significant cultural resources impact if it would: 1. Cause a substantial adverse change in the significance of a historical resource as defined in Section Cause a substantial adverse change in the significance of an archaeological resource pursuant to Section Directly or indirectly destroy a unique paleontological resource or site, or unique geologic feature. 4. Disturb any human remains, including those interred outside of formal cemeteries. D. Impact Discussion This section analyzes potential project-specific and cumulative impacts to cultural resources. 1. Cause a substantial adverse change in the significance of a historical resource as defined in Section A records search conducted during the preparation of the General Plan 2025 EIR revealed that there are no listed National Register properties, California Historical Landmarks, or locally-designated historical landmarks on or adjacent to the Project site. Although the City of Walnut Creek's historic built environment has been only partially inventoried, as described above, none of the existing structures on the Project site, including the BART station building and platforms, would be considered historically significant based on the

165 CULTURAL RESOURCES age criteria of either the SOHP or the National Register. In addition, no portion of the existing BART facilities would be deemed to be of exceptional importance such as to otherwise justify their inclusion on the National Register. Development in the vicinity of the Project site is generally 30 to 40 years old, the office towers to the north of the Project site having been built in the 1970s and 1980s, and the retail and residential buildings south of the Project site having been constructed in the 1970s or later. General Plan 2025 identifies two potentially significant historic resources in proximity to the Project site: Stan's Brick House (formerly Le Virage Restaurant), located at 2211 North Main Street and St. Paul's Episcopal Church, located at 1924 Trinity Avenue, approximately one block south of the Walnut Creek BART station. However, given the distance between the Project and these resources, and the scope of the Project, the significance of these historical resources would not be adversely affected by the Project. Therefore, development of the Project would not adversely affect the significance of any relevant historical resources and impacts would be less than significant. 2. Cause a substantial adverse change in the significance of an archaeological resource pursuant to Section The Project site is not included on the City's list of archaeologically sensitive sites, and as the site has been significantly disturbed, the likelihood that as-yetundiscovered archaeological resources are present on-site is low. Nevertheless, the Project site is located in an area of high archaeological sensitivity, with 15 sites of identified Native American artifacts and burial deposits in relatively close proximity, and as such the potential for uncovering as-yetundiscovered archaeological resources still exists, particularly during the excavation activities required for construction of the proposed buildings. Implementation of existing General Plan policies and actions would reduce potential adverse impacts to archaeological resources. Policy 24.1 requires

166 CULTURAL RESOURCES that the City review development proposals for potential impacts to archaeological resources and Action requires developers to halt all work if cultural resources are encountered during Project construction, and to retain a qualified archaeologist to evaluate and make recommendations for conservation and mitigation. Therefore, continued implementation of existing General Plan policies as well as compliance with applicable State standards described above in section A, Regulatory Framework, of this chapter, would ensure that impacts to archaeological resources from development of the Project would be less than significant. 3. Directly or indirectly destroy a unique paleontological resource or site, or unique geologic feature. The Project site is already almost entirely built out and contains no unique geological features. As described above, a search of the University of California Museum of Paleontology Specimen Search database indicated that there are no known paleontological resources within the City of Walnut Creek or on the Project site. Additionally, existing General Plan 2025 policies and actions described above, including Policy 24.1 and Action , would prevent adverse changes to as-yet-undiscovered paleontological resources to the maximum extent practicable, as would compliance with applicable State regulations described above in section A, Regulatory Framework, of this chapter. Therefore impacts to paleontological resources associated with development of the proposed Project would be less than significant. 4. Disturb any human remains, including those interred outside of formal cemeteries. The Project would have a significant environmental impact if it would disturb or destroy human remains, including those interred outside formal cemeteries or in Native American burial grounds. Although the Project site is already almost entirely built out, construction of the Project would involve excavation to a depth of 12-feet and as a result, the possibility that as-yetundiscovered human remains could be disturbed exists

167 CULTURAL RESOURCES During the preparation of this EIR, the City of Walnut Creek followed standard procedures required under Senate Bill 18 and invited consultation with local Native American groups. The Planning Center DC&E, the preparer of this EIR, sent letters to the following tribes: the Amah/Mutsun Tribal Band; the Indian Canyon Mutsun Band of Costanoan; the Muwekma Ohlone Tribe of the San Francisco Bay Area; and the Ohlone Indian Tribe. The City did not receive requests for consultation from any of these Native American groups. While there are no known human remains on the Project site, applicant is required to adhere to the existing State regulations and local policies, including those described above in Section A, Regulatory Framework, of this chapter, which would prevent disturbance or destruction of human remains to the maximum extent practicable. As such, associated impacts to human remains from buildout of the Project would be less than significant. E. Cumulative Impacts Cumulative impacts would occur when a series of actions leads to the loss of a substantial type of site, building, or resource. For example, while the loss of a single historic building may not be significant to the character of a neighborhood or streetscape, continued loss of such resources on a project-by-project basis could constitute a significant cumulative effect. This is most obvious in historic districts, where destruction or alteration of a percentage of the contributing elements may lead to a loss of integrity for the district overall. Changes to the setting or atmosphere of an area, for example, by adding modern structures on all sides of a historically significant building, thus altering the aesthetics of the streetscape, would create a significant impact. Destruction or relocation of historic buildings would also significantly impact the setting. As there are no historic structures and no known archaeological resources, paleontological resources, or human remains on the Project site, buildout of the proposed Project would not create or contribute to a cumulative impact

168 CULTURAL RESOURCES on cultural resources. Additionally, the existing federal, State, and local regulations and policies described throughout this chapter serve to protect any asyet-undiscovered cultural resources in Walnut Creek. Continued compliance with these regulations and implementation of existing policies, including applicable General Plan 2025 policies, would preclude impacts to historical, archaeological, and paleontological resources and to human remains to the maximum extent practicable. Therefore, in combination with past, present, and reasonably foreseeable projects, the proposed Project would result in a lessthan-significant cumulative impact with respect to cultural resources. F. Impacts and Mitigation Measures The Project would not result in any significant project-specific or cumulative impacts to cultural resources and therefore no mitigation measures are required

169 4.4 GEOLOGY AND SOILS This chapter provides an overview of existing geologic conditions within the Project site, and evaluates the potential for the proposed Project to result in significant direct and indirect environmental impacts related to geology and soils. A. Regulatory Framework 1. State Regulations a. Alquist-Priolo Earthquake Fault Zoning Act The Alquist-Priolo Earthquake Fault Zoning Act was passed in 1972 to mitigate the hazard of surface faulting to structures used for human occupancy. 1 The main purpose of the Act is to prevent the construction of buildings used for human occupancy on top of active faults. The Act only addresses the hazard of surface fault rupture and is not directed toward other earthquake hazards, such as ground shaking or landslides. 2 The law requires the State Geologist to establish regulatory zones (known as Earthquake Fault Zones or Alquist-Priolo Zones) around the surface traces of active faults, and to issue appropriate maps. 3 The maps are then distributed to all affected cities, counties, and State agencies for their use in planning and controlling new or renewed construction. Generally, construction within 50 feet of an active fault zone is prohibited. b. Seismic Hazards Mapping Act The Seismic Hazards Mapping Act, passed in 1990, addresses non-surface fault rupture earthquake hazards, including liquefaction and seismically-induced 1 Called the Alquist-Priolo Special Studies Zones Act until renamed in California Geological Survey, Alquist-Priolo Earthquake Fault Zones, accessed on May 25, Earthquake Fault Zones are regulatory zones around active faults. The zones vary in width, but average about ¼-mile wide. rghm/ap/index.htm, accessed on May 25,

170 GEOLOGY AND SOILS landslides. 4 Under this Act, seismic hazard zones are mapped by the State Geologist to assist local governments in land use planning. The Act states that it is necessary to identify and map seismic hazard zones in order for cities and counties to adequately prepare the safety element of their general plans and to encourage land use management policies and regulations to reduce and mitigate those hazards to protect public health and safety. 5 Section 2697(a) of the Act states that cities and counties shall require, prior to the approval of a project located in a seismic hazard zone, a geotechnical report defining and delineating any seismic hazard. 6 c. California Building Code The California Building Code (CBC), known as the California Building Standards Code, is included in Title 24 of the California Code of Regulations. The CBC incorporates the International Building Code, a model building code adopted across the United States. The CBC is updated every three years, and the current 2010 CBC took effect January 1, The 2010 CBC has been adopted for use by the City of Walnut Creek according to Chapter 9 of Title 9 of the Walnut Creek Municipal Code. Through the CBC, the State provides a minimum standard for building design and construction. The CBC contains specific requirements for seismic safety, excavation, foundations, retaining walls, and site demoli- 4 California Geological Survey, Alquist-Priolo Earthquake Fault Zones, accessed on May 25, California Public Resources Code, Division 2, Chapter 7.8, Article 7.8, Section 2691(c). 6 California Geological Survey-SHZP: About the Maps, conservation.ca.gov/cgs/shzp/pages/shmpdisclaimer.aspx, accessed on May 25, Welcome to the CGS Seismic Hazard Zonation Program (SHZP) Data Access Page, =All&Version=5&Browser=Netscape&Platform=Win, accessed on May 25,

171 GEOLOGY AND SOILS tion. It also regulates grading activities, including drainage and erosion control Local Regulations and Policies a. City of Walnut Creek General Plan 2025 The Safety and Noise chapter of the General Plan 2025 contains numerous policies and actions pertaining to geologic and seismic hazards. These policies and actions are intended to minimize the potential for loss of life, physical injury, and property damage resulting from seismic shaking and other geologic hazards. GOAL 1. Protect life and property from geologic hazards. Policy 1.1. Reduce the potential effects of seismic and other geologic hazards, including slope instability. Action Identify areas prone to seismic and other geologic hazards, including slope instability. Action Action Action Establish minimum road widths and clearances around structures at risk from known geologic hazards. Review and update the existing maps of geologic hazards. Require appropriate mitigations for new development or redevelopment in areas prone to seismic and other geologic hazards. Policy 1.2. Limit development within high-risk geologic areas to a maximum density of one dwelling unit per 20 acres. Action Identify high risk areas after taking into account soil stability, history of soil slippage, proximity 7 California Building Standards Commission, 2011, 2010 California Building Standards Administrative Code California Code of Regulations, Title 24, Part

172 GEOLOGY AND SOILS to earthquake faults, slope grade, accessibility and drainage conditions, and continue to assign low intensity uses, not exceeding a density of one dwelling unit per 20 acres, to such areas. Action Action Action Action As updated seismic hazard zone maps become available, incorporate them into the General Plan. Identify areas where surface ruptures are most likely to occur and cause damage to human-made structures, such as dams. For development proposals submitted in areas near earthquake fault zones listed under the Alquist-Priolo Act, require a geotechnical evaluation to identify hazard mitigation measures needed to reduce the risk to life and property from earthquake-induced hazards. For development proposals submitted in areas near high or very high liquefaction susceptibility areas, require a geotechnical evaluation to identify hazard mitigation measures needed to reduce the risk to life and property from earthquake-induced hazards. b. Walnut Creek Municipal Code Title 9, Chapter 9, Article 1 of the Walnut Creek Municipal Code establishes procedures and requirements for grading, excavation, and filling activities within the city in order to protect public health and safety, including through the reduction or elimination of the hazards of earth slides, mud flows, rock falls, undue settlement, and erosion. This section of the Municipal Code includes specific Best Management Practices (BMPs) for soil stabilization and erosion control

173 GEOLOGY AND SOILS B. Existing Conditions This section includes comprehensive analysis of the geotechnical conditions and soil resources located on the Project site. Three geotechnical reports were prepared for the Project by Kleinfelder, Inc., the applicant s geotechnical engineer. 8,9,10 The geotechnical reports are included in this Draft EIR in Appendix C. ENGEO, Inc., a geotechnical and hydrologic engineering firm, prepared a peer review of the Klienfelder reports, and also prepared this section of the Draft EIR. a. Site Soils and Bedrock Geology The Project site is located in the California Coast Ranges, approximately 5 miles west of Mount Diablo. According to published geologic maps, the bedrock formations underlying the Project site is the Monterey Formation, which consists primarily of sandstone and siltstone. The sandstone unit is locally known as the Sobrante Sandstone. The western portion of the site is mapped as Quaternary Alluvium, which consists of silts, sands, and gravels. The bedrock formations are striking to the northwest and dip angles toward the northeast between 74 and 80 degrees. Subsurface conditions are based on exploratory borings performed by Kleinfelder (2006 and 2004). In general, soil was encountered overlying bedrock at depths between 6 and 15 feet. In some cases, artificial fill was also encountered at depths between 5 and 14 feet. The artificial fills were presumably placed on the site primarily during construction of the BART station and adjacent parking areas. 8 Kleinfelder, Inc., Preliminary Geotechnical Investigation Report, Pinnacle at Walnut Creek Apartments, Walnut Creek, California, July 28, 2004, File No /RPT. 9 Kleinfelder, Inc., Preliminary Geotechnical Investigation Report, BART Transit Village East Parcel, Walnut Creek, California, August 4, 2006, File No /GEO. 10 Kleinfelder, Inc., Status of Soil and Groundwater Sampling and Testing for Sulfides and Sulfates, BART Transit Village, Walnut Creek, California, August 11, 2006(a), File No /GEO

174 GEOLOGY AND SOILS Clayey soils were identified on the site, which have moderate to high shrinkswell potential. Alternate wetting and drying of these soils as a result of moisture changes can result in significant changes in soil volume. In turn, this can cause heaving and cracking of slabs-on-grade, pavements, and structures founded on shallow foundations. Atterberg limits testing, including liquid limit and plastic limit testing, is another type of physical properties test used to determine the plasticity index and the potential for soil expansion. Soils with a plasticity index of 12 and above are considered to be expansive. Soils on site were found to have a plastic index range from 15 to b. Regional Faulting, Seismicity, and Related Seismic Hazards The Working Group on California Earthquake Probabilities estimates that the 30 year probability of a magnitude 6.7 or greater earthquake striking the San Francisco Bay area is 63 percent. 12 No active faults are known to pass directly through or near the Project site; however, an earthquake of moderate to high magnitude generated within the San Francisco Bay area could cause considerable ground shaking at the site. The degree of shaking is dependent on the magnitude of the event, the distance to its zone of rupture and local geologic conditions. The most active seismic sources in the vicinity of the Project site are the Concord and Calaveras faults (strike-slip faults) and the blind Mount Diablo thrust fault, located approximately 4, 7, and 5 miles southwest of the site, respectively. As shown in Figure 4.4-1, maximum earthquakes have been estimated for the Concord and Calaveras faults and Mount Diablo thrust fault 11 Kleinfelder, Inc., Preliminary Geotechnical Investigation Report, Pinnacle at Walnut Creek Apartments, Walnut Creek, California, July 28, 2004, File No /RPT. Kleinfelder, Inc., Preliminary Geotechnical Investigation Report, BART Transit Village East Parcel, Walnut Creek, California, August 4, 2006, File No /GEO Working Group on California Earthquake Probabilities, 2008, The Uniform California Earthquake Rupture Forecast, Version 2, of/2007/1437/

175 COLLAYOMI Lake HUNTING CREEK - BERRYESSA G R E A T V A L L E Y F A U L T DUNNIGAH HILLS BEAR MOUNTAINS TAHOE - SIERRA FRONTAL ccity ity of OF Walnut WALNUT creek CREEK WalnU t CREEk BART Ba RTRANSIT t t RansIVILLAGE t llage DRAFT DRa F t EIR GEOLOGY AND SOILS HOE - SIERRA FRONTAL GEYSER PEAK ALEXANDER-REDWOOD HILL MAACAMA Yolo El Dorado Sonoma Napa Alpine Alpine BENNETT VALLEY RODGERS CREEK Sacramento Amador TOLAY WEST NAPA CORDELIA SAN ANDREAS GREEN VALLEY VACA BEAR MOUNTAINS Calaveras Solano POINT REYES Marin HAYWARD CONCORD G R E A T V A L L E Y F A U L T ANTIOCH San Joaquin BEAR MOUNTAINS MELONES Tuolumne Tuolumne San Francisco Contra Costa CARNEGIE CORAL HOLLOW MIDWAY SAN GREGORIO San Mateo Alameda GREENVILLE SAN JOAQUIN Stanislaus Mariposa SILVER CREEK CALAVERAS Mariposa MONTE VISTA SHANNON SAN ANDREAS ZAYANTE SAN JOSE Santa Cruz SARGENT BERROCAL Santa Clara ORTIGALITA Merced SAN ANDREAS VERGELES nor t H Miles ORTIGALITA FIGURE Regional Faulting and SeiS micity

176 GEOLOGY AND SOILS at Mw 6.9, Mw 6.7, and Mw 6.7, respectively. 13,14 Although the aforementioned faults all pose potential seismic risks, the likelihood of surface fault rupture appears to be low because of their distance from the Project site. c. Landslides The Project site is relatively flat, sloping gently from approximately 182 feet above Mean Sea Level (MSL) datum on the southwest portion of the site to 168 MSL datum on the northeast portion of the site. Additionally, as shown on Figure 4.4-2, regional landslide mapping does not identify any landslide features or any historically mapped landslides on the Project site. 15 d. Liquefaction Soil liquefaction is a phenomenon where saturated, cohesionless, loose soils experience a temporary, but essentially total, loss of shear strength when subjected to the reversing cyclic shear stresses caused by earthquake ground shaking. A shown in Figure 4.4-3, the Project site is identified as having very low liquefaction susceptibility. Additionally, liquefiable soils were not identified in the Kleinfelder Report. e. Unstable Geologic Unit No unstable geologic units were encountered on site or are known to occur adjacent to the Project site Mw is an earthquake magnitude scale that is based on the total energy released, known as the seismic moment, in an earthquake and is not based on seismometer readings Working Group on California Earthquake Probabilities, 2008, The Uniform California Earthquake Rupture Forecast, Version 2, of/2007/1437/. 15 City of Walnut Creek, Walnut Creek General Plan 2025, Figure 4: Mapped Landslides and Slopes Greater than 15 percent, page Kleinfelder, Inc., Preliminary Geotechnical Investigation Report, Pinnacle at Walnut Creek Apartments, Walnut Creek, California, July 28, 2004, File No /RPT. Kleinfelder, Inc., Preliminary Geotechnical Investigation Report, BART Transit Village East Parcel, Walnut Creek, California, August 4, 2006, File No /GEO

177 GEOLOGY AND SOILS Proposed Project Site Base Map Date: January 16, 2004 NORTH Miles Source: Walnut Creek General Plan 2025 EIR FIGURE MAPPED LANDSLIDES AND SLOPES GREATER THAN 15 PERCENT IN WALNUT CREEK

178 GEOLOGY AND SOILS Proposed Project Site Base Map Date: January 16, 2004 NORTH Miles Source: Walnut Creek General Plan 2025 EIR FIGURE LIQUEFACTION SUSCEPTIBILITY

179 GEOLOGY AND SOILS C. Standards of Significance The Project would have a significant impact with regard to geology and soils if it would: 1. Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving: 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. Strong seismic ground shaking. Seismic-related ground failure, including liquefaction. Landslides. 2. Result in substantial soil erosion or the loss of topsoil. 3. Be located on a geologic unit or soil that is 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. 4. 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. 5. Have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of wastewater. D. Impact Discussion This section discusses potential land use impacts of the Project with respect to exposure to seismic and soils hazards. The construction of the proposed site structures should be designed with sound engineering judgment and the latest California Building Code (CBC) requirements as a minimum, taking into consideration the proposed use of the structures to be constructed

180 GEOLOGY AND SOILS 1. Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving: a. 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 Publication 42. As explained above, no known active faults have been mapped at the locations on or adjacent to the Project site, and the site is not located within an Alquist-Priolo Earthquake Fault Zone. 17 The potential for ground rupture is considered low at the Project site and therefore the associated impacts would be less than significant. b. Strong seismic ground shaking. Although the closest active fault to the Project site is located more than 4 miles away, an earthquake of moderate to high magnitude generated within the San Francisco Bay area could cause considerable ground shaking at the Project site. The effects of earthquake-related ground shaking could include possible damage to structures, changes in groundwater levels, and damage to streets and utilities. However, compliance with the latest California Building Code requirements would ensure the proposed structures would be able to: (1) resist minor earthquakes without damage, (2) resist moderate earthquakes without structural damage but with some nonstructural damage, and (3) resist major earthquakes without collapse but with some structural as well as nonstructural damage. Therefore, with adherence to existing regulations, impacts from development of the proposed Project associated with seismic ground shaking are considered less than significant. c. Seismic-related ground failure, including liquefaction. As described above and shown in Figure 4.4-3, the Project site is located in an area of very low susceptibility to liquefaction hazards. Soil investigations encountered clay and clayey soils, which are generally not susceptible to liq- 17 City of Walnut Creek, Walnut Creek General Plan 2025, Figure 2: Area Faults, page

181 GEOLOGY AND SOILS uefaction, and as such the impacts associated with liquefaction hazards are considered less than significant. d. Landslides. As described above, the Project site is relatively flat and there are no historically mapped landslides on the Project site. As shown in Figure 4.4-2, the Project site does not contain any slopes with gradients greater than 15 degrees, which would be considered susceptible to sliding. As such, there is no hazard due to landslides on the site and, therefore, there would be no impact. 2. Substantial soil erosion or the loss of topsoil. Substantial soil erosion or loss of topsoil during construction could undermine structures and minor slopes on the Project site; however, compliance with existing regulatory requirements, including the requirements of the SWRCB Construction General Permit ( DWQ) described in detail in Chapter 4.6, Hydrology and Water Quality, of this Draft EIR, to implement erosion control Best Management Practices (BMPs) would reduce impacts from the loss of topsoil to the maximum extent practicable. Typical soil stabilization BMPs include hydroseeding and short-term biodegradable erosion control blankets, silt fences or some kind of inlet protection at downstream storm drain inlets, post-construction inspection of all drainage facilities for accumulated sediment, and post-construction clearing of all drainage structures of debris and sediment. Therefore, adherence to existing regulatory requirements would ensure that impacts associated with substantial erosion and loss of topsoil resulting from buildout of the proposed Project would be less than significant. 3. Be located on a geologic unit or soil that is 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

182 GEOLOGY AND SOILS No unstable geologic units were encountered during geotechnical investigations of the site performed by Kleinfelder. 18 Likewise, the Project would not cause any on-site geologic units to become unstable. As described above, the Project site is identified as having very low liquefaction susceptibility and no unstable geologic units were encountered on site or are known to occur adjacent to the Project site. Therefore, associated impacts from development of the Project would be less than significant. 4. 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. As described above, geotechnical investigations of the Project site encountered soils with a plastic index ranging between 15 and 26. As such, soils on the Project site are moderate to highly expansive. However, the proposed Project would be subject to the California Building Code regulations and provisions described above, as adopted and enforced by the City of Walnut Creek during plan review and before issuing building permits. The CBC contains specific requirements for seismic safety, excavation, foundations, retaining walls and site demolition, and also regulates grading activities, including drainage and erosion control. Compliance with the existing regulations and provisions would ensure that the Project impacts would reduce potential impacts to a less-than-significant level. 5. Have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of wastewater. The Project does not propose the use of septic tanks. Wastewater from the Project would be discharged into the existing sanitary sewer system in Walnut Creek. As such, there would be no impact from the Project associated with 18 Kleinfelder, Inc., Preliminary Geotechnical Investigation Report, Pinnacle at Walnut Creek Apartments, Walnut Creek, California, July 28, 2004, File No /RPT. Kleinfelder, Inc., Preliminary Geotechnical Investigation Report, BART Transit Village East Parcel, Walnut Creek, California, August 4, 2006, File No /GEO

183 GEOLOGY AND SOILS soils adequate for the use of septic tanks or alternative wastewater disposal systems. E. Cumulative Impacts This section analyzes potential geological impacts that could occur from a combination of the proposed Project with other past, present, and reasonably foreseeable projects in the near vicinity. The list of projects considered in this section is shown in Chapter 4, and the geographic scope of this analysis is taken as the City of Walnut Creek. Given the distance of known active faults from Walnut Creek, the risk of fault rupture within the city limit is minimal. Additionally, all development in Walnut Creek would be subject to California Building Code requirements and provisions, and compliance with these requirements and provisions would minimize cumulative impacts from development associated with ground-shaking, liquefaction, and expansive soils to the maximum extent practicable. Similarly, the requirements and provisions of the City's Grading Ordinance would apply to all development in Walnut Creek, and implementation of stipulated BMPs would minimize cumulative impacts associated with soil erosion and loss of topsoil to the maximum extent practicable. As the Project site is not located on an unstable geologic unit or in an area at risk of landslides, buildout of the Project would not create a project-level impact or contribute to an associated cumulative impact either. Overall, cumulative impacts associated with development of the proposed Project in combination with other past, present, and reasonably foreseeable projects in the surrounding area would result in a less-than-significant cumulative impact with respect to geologic hazards and soils

184 GEOLOGY AND SOILS F. Impacts and Mitigation Measures The Project would not result in any significant project-specific or cumulative impacts to geological hazards and soils, and therefore no mitigation measures are required

185 4.5 HAZARDS AND HAZARDOUS MATERIALS This chapter discusses existing conditions on the Project site and in the vicinity and potential impacts of the Project related to hazardous materials, airport hazards, emergency response plans and wildland fires. Potential Project impacts related to fire protection services other than wildland fires are discussed in Section 4.10, Public Services and Recreation. A. Regulatory Framework This section summarizes existing federal, State, regional, and local policies and regulations that apply to hazards and hazardous materials. 1. Federal Programs and Regulations The following federal agencies oversee hazards and hazardous materials concerns. a. Environmental Protection Agency The United States Environmental Protection Agency s (EPA) laws and regulations ensure the safe production, handling, disposal and transportation of hazardous materials. Laws and regulations established by the EPA are enforced in Contra Costa County by the California EPA. b. U.S. Department of Transportation Transportation of chemicals and hazardous materials are governed by the United States Department of Transportation (DOT), which stipulates the types of containers, labeling, and other restrictions to be used in the movement of such material on interstate highways. c. Occupational Safety and Health Administration The Occupational Safety and Health Administration (OSHA) oversees administration of the Occupational Safety and Health Act, which requires: specific training for hazardous materials handlers; provision of information to employees who may be exposed to hazardous materials; and acquisition of material safety data sheets (MSDS) from materials manufacturers. Material safety data sheets describe the risks, as well as proper handling and procedures 4.5-1

186 HAZARDS AND HAZARDOUS MATERIALS related to particular hazardous materials. Employee training must include response and remediation procedures for hazardous materials releases and exposures. 2. State Programs and Regulations a. California Health and Safety Code and Code of Regulations California Health and Safety Code Chapter 6.95 and 19 California Code of Regulations Section 2729 set out the minimum requirements for business emergency plans and chemical inventory reporting. These regulations require businesses to provide emergency response plans and procedures, training program information, and a hazardous material chemical inventory disclosing hazardous materials stored, used, or handled on site. A business which uses hazardous materials or a mixture containing hazardous materials must establish and implement a business plan if the hazardous material is handled in certain quantities. b. California Environmental Protection Agency One of the primary agencies that regulates hazardous materials is the California Environmental Protection Agency (CalEPA), which is authorized by the EPA to enforce and implement federal hazardous materials laws and regulations. The Department of Toxic Substance Control (DTSC), a department of the CalEPA, protects California and Californians from exposure to hazardous waste, primarily under the authority of the federal Resource Conservation Recovery Act (RCRA) of 1976 and the California Health and Safety Code. 1 DTSC requirements include the need for written programs and response plans, such as Hazardous Materials Business Plans (HMBPs). DTSC programs include dealing with aftermath clean-ups of improper hazardous waste management, evaluation of samples taken from sites, enforcement of regulations regarding use, storage and disposal of hazardous materials, and encouragement of pollution prevention. 1 Department of Toxic Substances Control website gov/informationresources/dtsc_overview.cfm#overview_of_dtsc, accessed on May 25,

187 HAZARDS AND HAZARDOUS MATERIALS c. California Division of Occupational Safety and Health (Cal OSHA) Like OSHA at the federal level, Cal OSHA is the responsible state-level agency for ensuring workplace safety. Cal OSHA assumes primary responsibility for the adoption and enforcement of standards regarding workplace safety and safety practices. In the event that a site is contaminated, a Site Safety Plan must be crafted and implemented to protect the safety of workers. Site Safety Plans establish policies, practices, and procedures to prevent the exposure of workers and members of the public to hazardous materials originating from the contaminated site or building. d. California Fire Code (2010) California Code of Regulations, Title 24, also known as the California Building Standards Code, contains the California Fire Code (CFC), included as Part 9 of that title. Updated every three years, the CFC includes provisions and standards for emergency planning and preparedness, fire service features, fire protection systems, hazardous materials, fire flow requirements, and fire hydrant locations and distribution. e. The California Department of Transportation The California Department of Transportation (Caltrans) manages more than 50,000 miles of California's highway and freeway lanes, provides inter-city rail services, permits more than 400 public-use airports and special-use hospital heliports and works with local agencies. Caltrans is also the first responder for hazardous material spills and releases that occur on those highway and freeway lanes and inter-city rail services. f. State Water Resources Control Board The San Francisco Bay Regional Water Quality Control Board (RWQCB) is authorized by the State Water Resources Control Board (SWRCB) to enforce provisions of the Porter-Cologne Water Quality Control Act of This act gives the San Francisco RWQCB authority to require groundwater investigations when the quality of groundwater or surface waters of the State is threatened and to require remediation of the site, if necessary

188 HAZARDS AND HAZARDOUS MATERIALS 3. Materials-Specific Programs and Regulations a. Asbestos-Containing Materials (ACM) Regulations State-level agencies, in conjunction with the federal EPA and OSHA, regulate removal, abatement, and transport procedures for asbestos-containing materials. Releases of asbestos from industrial, demolition, or construction activities are prohibited by these regulations and medical evaluation and monitoring is required for employees performing activities that could expose them to asbestos. Additionally, the regulations include warnings that must be heeded and practices that must be followed to reduce the risk for asbestos emissions and exposure. Finally, federal, State, and local agencies must be notified prior to the onset of demolition or construction activities with the potential to release asbestos. b. Polychlorinated Biphenyls (PCBs) The U.S. EPA prohibited the use of PCBs in the majority of new electrical equipment starting in 1979, and initiated a phase-out for much of the existing PCB-containing equipment. The inclusion of PCBs in electrical equipment and the handling of those PCBs are regulated by the provisions of the Toxic Substances Control Act, 15 U.S.C et seq. (TSCA). Relevant regulations include labeling and periodic inspection requirements for certain types of PCB-containing equipment and outline highly specific safety procedures for their disposal. The State of California likewise regulates PCB-laden electrical equipment and materials contaminated above a certain threshold as hazardous waste; these regulations require that such materials be treated, transported, and disposed accordingly. At lower concentrations for non-liquids, regional water quality control boards may exercise discretion over the classification of such wastes. c. Lead-based Paint (LBP) Cal OSHA s Lead in Construction Standard is contained in Title 8, Section of the California Code of Regulations. The regulations address all of the following areas: permissible exposure limits (PELs); exposure assessment; compliance methods; respiratory protection; protective clothing and equipment; housekeeping; medical surveillance; medical removal protection 4.5-4

189 HAZARDS AND HAZARDOUS MATERIALS (MRP); employee information, training, and certification; signage; record keeping; monitoring; and agency notification. 4. Local Programs and Regulations a. Walnut Creek General Plan 2025 The Safety and Noise Chapter of General Plan 2025 contains the following goals, policies, and actions related to hazardous materials and emergency response. GOAL 3. Reduce dangers from hazardous materials. Policy 3.1. Policy 3.2. Policy 3.3. Policy 3.4. Facilitate the proper disposal of hazardous materials. Prioritize safety needs of non-industrial land uses. Incorporate hazardous materials abatement provisions in zoning and subdivision decisions and entitlement permits. Work with federal and State authorities to ensure that any transport of hazardous materials through Walnut Creek is at the highest standard of safety. Action Designate hazardous material carrier routes that direct hazardous materials away from populated and other sensitive areas. Policy 3.5. Require that soils, groundwater, and buildings affected by hazardous material releases from prior land uses, and lead and asbestos potentially present in building materials, will not have the potential to adversely affect the environment or the health and safety of residents. Action Require an environmental investigation for hazardous materials when reviewing applications for new development in former commercial or industrial areas. Policy 3.6. Require that new development and redevelopment protect public health and safety from hazardous materials

190 HAZARDS AND HAZARDOUS MATERIALS Action Require environmental investigations stipulated by State and County regulations for potential hazardous material releases from prior uses, as well as for lead and asbestos present in building materials. GOAL 6. Provide quick response to disasters. Policy 6.1. In the event of a disaster, strive to reduce injury, loss of life, and property damage. Action Prepare and adopt a list and map of evacuation routes. b. Emergency Operations Plan The City of Walnut Creek has prepared an Emergency Operations Plan (EOP) that identifies and allocates resources in response to emergencies, from preparation through recovery. The EOP identifies the City s emergency planning, organizational, and response policies and procedures and how they would be coordinated with emergency responses from other levels of government. 2 B. Existing Conditions This section described existing conditions on the Project site and in the surrounding area related to hazardous materials, airport hazards, and wildland fires. 1. Hazardous Materials a. Transport, Use, and Disposal of Hazardous Materials Operation of the BART station involves minimal use of hazardous materials. There are no maintenance or storage yards for BART trains on-site; however, machinery lubricants and cleaning supplies are used for routine operation and 2 Walnut Creek General Plan Chapter 6, Safety and Noise, page

191 HAZARDS AND HAZARDOUS MATERIALS maintenance are stored on-site. The traction power substation has two transformers, each containing 1,195 gallons of dielectric oil. The substation also contains batteries below the Hazardous Materials Business Plan (HMBP) reporting threshold. The four-level parking structure has a diesel generator with a 50-gallon fuel tank, which is also below the HMBP reporting threshold. Additionally, vehicles traveling through the Project site or parked onsite are another source of hazardous substances. Small quantities of petrochemicals and other fluids that leak from vehicles are present on the paved surfaces of the Project site and on surrounding roadways. b. Known Hazardous Materials Sites In 2003, a Phase 1 Environmental Site Assessment (Phase 1 ESA) was completed for the portion of the Project site west of the BART tracks excluding the existing BART parking garage. This 10-acre portion of the Project site was used for residential purposes from at least 1921 to approximately Subsequently, in 1970, the portion of the Project site west of the BART tracks between Pringle Avenue and Ygnacio Valley Road was cleared and graded to allow for development of the Walnut Creek BART station. Since the early 1970s, the western portion of the Project site has been developed with a four-level parking structure; parking lots; and internal roadways for the BART station. The Phase 1 ESA was performed by SECOR International in compliance with the American Society for Testing and Materials (ASTM) Standard Practice for Environmental Site Assessments: Phase 1 Environmental Site Assessment Process, Designation E Based on site reconnaissance, review of regulatory agency lists and files, review of the history of the property, and interviews with people familiar with the history and past uses of the site, the Phase 1 ESA determined that there was no presence or likely presence of hazardous substances or petroleum products which would indicate an existing release, 3 SECOR International Inc., Phase 1 Environment Site Assessment for B.R.E. Properties, Inc., and Walnut Creek Transit Village Lifestyle Associates, LLC. See Appendix D of this Draft EIR

192 HAZARDS AND HAZARDOUS MATERIALS past release, or material threat of release of hazardous substances on the Project site. Additionally, a search of the DTSC Envirostor database was conducted to check for contaminated sites in the vicinity of the Project site. The Envirostor database includes lists of the following site types: Federal Superfund Sites, State Response Sites, Voluntary Cleanup Sites, School Cleanup Sites, Corrective Action Sites, and Tiered Permit Sites. Envirostor provides the site name, site type, status, address, any restricted use and/or recorded deed restrictions, past use(s) that caused contamination, potential contaminants of concern, site history, and planned and completed activities. As of November 2011, there were no sites in the Envirostor database within one-half mile of the Project site. 4 Envirostor also gives access to the SWRCB Geotracker database which contains records of Leaking Underground Storage Tanks (LUST) and Spills, Leaks, Investigation, and Cleanups sites (SLIC). As of November 2011, there was one open case for a LUST site within 1000 feet of the Project site. This LUST site is 115 feet to the southeast of the Project site, on the opposite side of Ygnacio Valley Road from the Project site, and located at 265 Ygnacio Valley Road. 5 This is the location of a Shell station that has leaked gasoline into groundwater. The site had been serving as a gas station since the 1950s and available data indicate that this case began in 2001; however, the leakage may have begun prior to this date. A monitoring plan has been established for this site and monitoring reports are published semi-annually. The distances from the two nearest monitoring wells from the Project site were approximately 130 feet and 150 feet, with both monitoring wells located to the southeast of the Project site. The most recent monitoring report, dated January 2012, indicates that the groundwater was located at a depth of 13.5 to 18.7 feet below 4 California Department of Toxic Substances (DTSC), Envirostor Database accessed on November 11, State Water Resources Control Board (SWRCB), Geotracker Database accessed on November 11,

193 HAZARDS AND HAZARDOUS MATERIALS the test well heads and was flowing towards the southeast and therefore directly away from the Project site Airport Hazards The nearest public use airport, Buchanan Field Airport, located at 550 Sally Ride Drive in Concord, California, is approximately 5 miles north of the Project site. The comprehensive Airport Land Use Plan for Contra Costa County indicates that the airport s outer safety zone, Safety Zone 4, ends approximately 5,000 feet from the edge of the southern most runway, or about 4 miles north of the Project site. 7 There are no private airstrips in the vicinity of the Project site. 3. Wildland Fire Hazard Walnut Creek is surrounded by extensive areas of hillside open space, which pose a wildland fire risk. Wildland fire hazard is a product of several factors, including weather, slope, fuel (vegetation, ground cover, building materials), access to fire suppression services, and water supply and water pressure. The California Department of Forestry and Fire Protection (CDF) has mapped the relative fire risk in areas of significant population, based on development density and proximate fire threat. Levels of risk are indicated as Little or No Threat, Moderate, High, Very High and Extreme. As shown in Figure 4.5-1, the Project site is located in an area of high threat to people from wildland fires; however, this is principally because CDF maps wildland fires to include a 1.5-mile buffer. The Project site is located in a highly urbanized area and is not surrounded by woodlands or vegetation which would provide fuel load for wildfires. 6 Conestoga-Rovers & Associates, Groundwater Monitoring Report Fourth Quarter 2011: 265 Ygnacio Valley Road, Walnut Creek, California, Reference No , /T PDF, Accessed on June 4, Contra Costa County Airport Land Use Compatibility Plan, Chapter 3 Buchanan Field Airport Policies, page

194 Buena Vista Ave CITY OF WALNUT CREEK HAZARDS AND HAZARDOUS MATERIALS Pleasant Hill Concord BART Treat Blvd Oak Grove Rd Geary Road N Main St Bancroft Rd Ygnacio Valley Rd Boundary Oak Lime Ridge Open Space Heather Farm Proposed Project Site I-680 Civic Dr Walnut Ave Castle Rock Rd Hwy 24 BART Lafayette Walnut Blvd Olympic Blvd Shell Ridge Open Space Rudgear Rd Tice Valley Blvd I-680 Rossmoor Pkwy Threat to People From Wildland Fire Moderate High Very High NORTH Alamo Miles Source: Department of Forestry and Fire Protection, 2003 Extreme Highways Major Roads Planning Area Boundary Note: See text for further explanation of threat categories. FIGURE THREAT TO PEOPLE FROM WILDLAND FIRE

195 HAZARDS AND HAZARDOUS MATERIALS The Contra Costa County Fire Protection District (CCCFPD) provides fire protection services to Walnut Creek and surrounding unincorporated areas of Contra Costa County, including areas of potential wildland fire hazard. The CCCFPD endeavors to minimize fire risk through its weed-abatement program, which covers all wildland areas within the County s jurisdiction. The CCCFPD also works with Mt. Diablo State Park and the San Ramon Valley Fire District in addressing wildland fire hazards. C. Standards of Significance The proposed Project would have a significant impact regarding hazards and hazardous materials if it would: 1. Create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials. 2. 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. 3. Emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within ¼-mile of an existing or proposed school. 4. Be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code Section and, as a result, create a significant hazard to the public or the environment. 5. Be located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, result in a safety hazard for people residing or working in the Project area. 6. Be within the vicinity of a private airstrip, result in a safety hazard for people residing or working in the Project area. 7. Impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan

196 HAZARDS AND HAZARDOUS MATERIALS 8. Expose people or structures to a significant risk of loss, injury or death involving wildland fires, including where wildlands are adjacent to urbanized areas or where residences are intermixed with wildlands. D. Impact Discussion This section discusses potential project-specific and cumulative impacts related to hazardous materials, airport hazards, emergency response plans, and wildland fires. 1. Create a significant hazard to the public or the environment through the routine transport, use, or disposal of hazardous materials. Based on the current and historical land uses at the Project site and the results of the Phase I ESA, it is unlikely that construction workers or the public could be exposed to hazardous materials as a result of Project demolition or construction activities. Project pre-construction would involve the excavation and removal of existing parking lot asphalt. DHS does not consider hardened bulk waste asphalt to be a hazardous waste. Disposal of nonhazardous waste is regulated by the RWQCB. Waste asphalt from the site could be disposed of at a disposal facility that is permitted to accept waste asphalt or could be recycled at an asphalt batch plant. Compliance with applicable federal, State, and local regulations would ensure that potential impacts to workers or the public from the discovery of hazardous materials, including ACMs, LBs, and PCBs during demolition of on-site structures, are minimized to the maximum extent practicable. Construction of the proposed Project would involve the use and handling of small amounts of hazardous materials (e.g. diesel gasoline, fertilizers, etc.). Construction activities at the Project site would also involve the use of petroleum-based fuels for maintenance and construction equipment, which would be transported to the site periodically by vehicle and would be present temporarily during construction. Implementation of federal Occupational Safety and Health Administration (OSHA) and California OSHA regulations would reduce the potential health risk of on-site construction to the maximum ex

197 HAZARDS AND HAZARDOUS MATERIALS tent practicable. Therefore, impacts related to the routine transport, use, or disposal of hazardous materials associated with Project demolition and construction activities would be less than significant. During the operational phase of the Project, common cleaning substances, building maintenance products, batteries, paints and solvents, and similar items would be stored, used, and disposed of in the four mixed-use buildings and the office space that would be leased and occupied by BART Police. These potentially hazardous materials, however, would not be of a type or occur in sufficient quantities on-site to pose a significant hazard to public health and safety or the environment. In addition, the transport, use, and disposal of hazardous materials are extensively regulated by the governmental agencies described above in section A, Regulatory Framework. Compliance with the regulations under their respective jurisdictions would be required of all activities involving hazardous materials on site. Consequently, associated impacts from development of the Project would be less than significant. 2. 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. During the construction phase of the Project, limited quantities of hazardous materials such as gasoline, diesel, hydraulic fluid, etc., may be transported and used at the Project site. Any potential spill of such materials would be contained and addressed in compliance with the Storm Water Pollution Prevention Plan (SWPPP) for the Project. 8 As described above, compliance with applicable federal, State, and local regulations would ensure that potential impacts to workers or the public from the accidental discovery of hazardous materials, including ACMs, LBPs, and PCBs during demolition of on-site structures, are minimized to the maximum extent practicable. 8 See chapter 4.6 Hydrology and Water Quality, of this Draft EIR for further discussion of the SWPPP required for the Project

198 HAZARDS AND HAZARDOUS MATERIALS While operation of the Project would involve the storage, use, and disposal of common cleaning substances, building maintenance products, batteries, paints and solvents in the proposed mixed-use buildings and the office space that would be leased and occupied by BART Police, these potentially hazardous substances would not be of a type or occur in sufficient quantities on-site to pose a significant hazard to public health and safety or the environment. Additionally, operation of the Project would locate residences and businesses in close proximity to the BART station, which has a traction power substation with two transformers, each containing 1,195 gallons of dielectric oil. This substation contains batteries that are below the Hazardous Materials Business Plan (HMBP) reporting threshold. Additionally, the parking garage has a diesel generator with a 50 gallon fuel tank, also below the HMBP reporting threshold. The storage, use, and disposal of these materials would be subject to the federal, State, and local regulations listed above in section A, Regulatory Framework. Compliance with these regulations, which is required under the law, would ensure that the risk of accidents and spills are minimized to the maximum extent practicable. Consequently, overall, associated impacts would be less than significant. 3. Emit hazardous emissions or handle hazardous or acutely hazardous materials, substances, or waste within ¼-mile of an existing or proposed school. There are no schools located within a quarter mile of the Project site. The closest school, Buena Vista Elementary, is located 0.5 miles from the Project site at 2355 San Juan Avenue, west of I-680. Additionally, as described above, the Project would not involve the storage, handling, or disposal of hazardous materials that would pose a significant risk to the public. Therefore, there would be no impact related to hazardous emissions or hazardous material handling within ¼-mile of a school

199 HAZARDS AND HAZARDOUS MATERIALS 4. Be located on a site which is included on a list of hazardous materials sites compiled pursuant to Government Code Section and, as a result, create a significant hazard to the public or the environment. As described above, on the basis of the Phase 1 ESA and records searches of the Envirostor and Geotracker databases, it was determined that the Project site is not on a list of hazardous materials sites. However, 115 feet to the south of the Project site, at 265 Ygnacio Valley Road, gasoline from an underground storage tank at a Shell station has leaked into the groundwater. A monitoring plan for the 265 Ygnacio Valley Road site has been prepared under the supervision of the RWQCB, and recent monitoring reports indicate no substantial adverse change in analytical data or pollutant concentrations at the site. Groundwater under 265 Ygnacio Valley Road flows to the southeast and therefore directly away from the proposed Project site. As such, continued implementation of the monitoring plan and continued compliance with applicable federal, State, and local regulations would ensure that associated impacts are reduced to the maximum extent practicable. Therefore, buildout of the proposed Project would not create a significant hazard to the public or the environment by virtue of location in proximity to a known hazardous materials site. Impacts would be less than significant. 5. Be located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, and result in a safety hazard for people residing or working in the Project area. Buchanan Field Airport, the nearest public use airport, is located approximately 5 miles north of the Project site. Given the distance from the nearest public use airport, the Project would not be subject to any airport safety hazards. The Project would also not have an adverse effect on aviation safety or flight patterns. Thus, there would be no impact related to public airport hazards

200 HAZARDS AND HAZARDOUS MATERIALS 6. Be within the vicinity of a private airstrip and result in a safety hazard for people residing or working in the Project area. There are no private airstrips in the vicinity of the Project site and therefore no impact related to private airstrip hazards. 7. Impair implementation of or physically interfere with an adopted emergency response plan or emergency evacuation plan. Buildout of the proposed Project would result in changes to current circulation through the site for emergency vehicles, cars, buses, bicycles, and pedestrians; however, no physical components that would interfere with the ability to implement emergency response are proposed. Project plans include fire and emergency access through all phases of construction and operation. 9 Compliance with the provisions of the 2010 California Fire Code and the 2010 California Building Code would ensure that buildout of the Project would result in a less-than-significant impact with respect to interference with an adopted emergency response plan or emergency evacuation plan. 8. Expose people or structures to a significant risk of loss, injury or death involving wildland fires, including where wildlands are adjacent to urbanized areas or where residences are intermixed with wildlands. As described above and shown in Figure 4.5-1, the Project site is not located in an area designated by CDF as Extreme or Very High threat to people from wildland fire. Although CDF maps designate the Project site and its vicinity as an area of High threat, this is principally because CDF maps wildland fires to include a 1.5-mile buffer. The Project site is located in a highly urbanized area and is not surrounded by woodlands or vegetation which would provide fuel load for wildfires. The CCCFPD conducts a weed-abatement program throughout its jurisdiction to minimize fire risk in wildland areas, and the CCCFPD also cooperates with Mt. Diablo State Park and the San Ramon Valley Fire District in addressing wildland fire hazards. Continuation of these initiatives would ensure that the risk of wildland fires is reduced to the 9 Walnut Creek Lifestyle Associates, Walnut Creek Transit Village Project Plans, McLarand Vasquez Emsiek & Partners, Inc

201 HAZARDS AND HAZARDOUS MATERIALS maximum extent practicable. As such, overall, the risk of loss, injury, or death resulting from wildland fire would be less than significant. E. Cumulative Impacts This section analyzes potential impacts related to hazards and hazardous materials that could occur from a combination of the proposed Project with other past, present, and reasonably foreseeable projects in the near vicinity. The list of projects considered in this section is shown in Chapter 4.0, and the geographic scope of this analysis is taken as the City of Walnut Creek. Past, present, and reasonably foreseeable projects in the area around the Project site are generally residential, mixed-use, and commercial developments. Development of these cumulative projects would involve increased storage, use, and disposal of common cleaning substances, building maintenance products, batteries, paints and solvents; however, these potentially hazardous materials would not be of a type or occur in sufficient quantities to pose a significant hazard to public health and safety or the environment. While cumulative development in the vicinity of the Project site would bring more residents, shoppers, and employees into the area, compliance with existing federal, State, and local regulations and standards would ensure that risks associated with the transport, storage, use, and disposal of hazardous materials and waste would be reduced to the maximum extent practicable. As described above, there are no Federal Superfund Sites, State Response Sites, Voluntary Cleanup Sites, School Cleanup Sites, Corrective Action Sites, or Tiered Permit Sites in the vicinity of the Walnut Creek BART station. While there is one known leaking underground storage tank site currently under assessment by the SWRCB at 265 Ygnacio Valley Road, a monitoring plan has been established for this site and recent monitoring reports indicate no substantial adverse change in analytical data or pollutant concentrations at the site. Continued implementation of the monitoring plan and continued compliance with applicable federal, State, and local regulations would ensure that associated impacts are reduced to the maximum extent practicable and

202 HAZARDS AND HAZARDOUS MATERIALS that development of cumulative projects would not expose a significant number of additional people to substantial risk. The closest airport or private airstrip to Walnut Creek is Buchanan Field Airport, located approximately 5 miles north of the Walnut Creek BART station. Given the distance of this airport from the vicinity of the Project site, the increased average daily population that would result from development of cumulative projects would not adversely affect airport hazards. Development in Walnut Creek is subject to the City's Municipal Code, which incorporates the provisions of the 2010 California Fire Code and the 2010 California Building Code. Compliance with these standards and regulations would ensure that buildout of cumulative projects would result in a less-thansignificant impact with respect to interference with an adopted emergency response plan or emergency evacuation plan. The Project site and its surrounding area are not designated as areas of Extreme or Very High threat to people from wildland fires, and as such the area is not considered to contain substantial forest fire risks or hazards. Additionally, the CCCFPD conducts a weed-abatement program throughout its jurisdiction to minimize fire risk in wildland areas, and also cooperates with Mt. Diablo State Park and the San Ramon Valley Fire District in addressing wildland fire hazards. Continuation of these initiatives would ensure that the cumulative risk of wildland fires is reduced to less-than-significant levels. Consequently, buildout of the proposed Project in combination with past, present, and reasonably foreseeable projects in the near vicinity would not result in a significant cumulative impact. Cumulative impacts associated with hazards and hazardous materials would be less than significant. F. Impacts and Mitigation Measures The Project would not result in any significant project-specific or cumulative impacts to hazards or hazardous materials and therefore no mitigation measures are required

203 4.6 HYDROLOGY AND WATER QUALITY This chapter discusses the regulatory environment, existing conditions and impacts of the Project related to hydrology and water quality. A. Regulatory Environment 1. Federal Regulations a. Federal Emergency Management Agency 1 The Federal Emergency Management Agency (FEMA) administers the National Flood Insurance Program (NFIP) to provide subsidized flood insurance to communities that comply with FEMA regulations limiting development in floodplains. FEMA also issues Flood Insurance Rate Maps (FIRMs) that identify which land areas are subject to flooding. These maps provide flood information and identify flood hazard zones in the community. The design standard for flood protection is established by FEMA. FEMA s minimum level of flood protection for new development is the 100-year flood event, also described as a flood that has a 1-in-100 chance of occurring in any given year. Additionally, FEMA has developed requirements and procedures for evaluating earthen levee systems and mapping the areas affected by those systems. 2 Levee systems are evaluated for their ability to provide protection from 100- year flood events and the results of this evaluation are documented in the FEMA Levee Inventory System (FLIS). Levee systems must meet minimum freeboard standards and must be maintained according to an officially adopted maintenance plan. Other FEMA levee system evaluation criteria include structural design and interior drainage. 1 Federal Emergency Management Agency s website, gov/hazard/flood/index.shtm, accessed on December 23, Federal Emergency Management Agency (FEMA), Guidelines and Specifications for Flood Hazard Mapping Partners, viewrecord.do?id=2206, accessed on December 23,

204 H YDROLOGY AND WATER QUALITY b. Clean Water Act The U.S. Environmental Protection Agency (EPA) is the lead federal agency responsible for water quality management. The Clean Water Act (CWA, codified at 33 U.S.C. Sections ) of 1972 is the primary federal law that governs and authorizes water quality control activities by the EPA, as well as the states. Various elements of the CWA address water quality, and they are discussed below. Wetland protection elements, including permits to dredge or fill wetlands, are administered by the U.S. Army Corps of Engineers under Section 404 of the CWA. Under Section 401 of the CWA, an applicant for a Section 404 permit to discharge dredged or fill material into waters of the United States must first obtain a certificate from the appropriate State agency stating that the fill is consistent with the State s water quality standards and criteria. In California, the authority to either grant water quality certification or waive the requirement is delegated by the State Water Resources Control Board (SWRCB) to its nine Regional Water Quality Control Boards (RWQCBs). Under federal law, the EPA has published water quality regulations under Volume 40 of the Code of Federal Regulations (40 CFR). Section 303 of the CWA requires states to adopt water quality standards for all surface waters of the United States. As defined by the CWA, water quality standards consist of two elements: (1) designated beneficial uses of the water body in question and (2) criteria that protect the designated uses. Section 304(a) requires the EPA to publish advisory water quality criteria that accurately reflect the latest scientific knowledge on the kind and extent of all effects on health and welfare that may be expected from the presence of pollutants in water. Where multiple uses exist, water quality standards must protect the most sensitive use. In California, the EPA has designated the SWRCB and its RWQCBs with authority to identify beneficial uses and adopt applicable water quality objectives

205 HYDROLOGY AND WATER QUALITY c. National Pollutant Discharge Elimination System The National Pollutant Discharge Elimination System (NPDES) permit program was established by the CWA to regulate municipal and industrial discharges to surface waters of the United States, including discharges from municipal separate storm sewer systems (MS4s). Federal NPDES permit regulations have been established for broad categories of discharges, including pointsource municipal waste discharges and nonpoint-source stormwater runoff. NPDES permits generally identify effluent and receiving water limits on allowable concentrations and/or mass emissions of pollutants contained in the discharge; prohibitions on discharges not specifically allowed under the permit; and provisions that describe required actions by the discharger, including industrial pretreatment, pollution prevention, self-monitoring and other activities. 2. State Regulations a. Porter-Cologne Water Quality Control Act The Porter-Cologne Water Quality Control Act (Porter-Cologne Act, codified in Division 7 of the California Water Code) of 1969 is California s statutory authority for the protection of water quality. Under the Act, the State must adopt water quality policies, plans, and objectives that protect the State s waters for the use and enjoyment of the people. Such waters of the State include streams, groundwater, isolated wetlands, and other bodies of water that are not under federal jurisdiction as waters of the United States (under the Clean Water Act). These waters include those which are not tributary to navigable waterways. The Act sets forth the obligations of the SWRCB and RWQCBs to adopt and periodically update water quality control plans (Basin Plans). Basin Plans are the regional water quality control plans required by both the CWA and Porter-Cologne Act in which beneficial uses, water quality objectives, and implementation programs are established for each of the nine regions in California. The Act also requires waste dischargers to notify the RWQCBs of their activities through the filing of Reports of Waste Discharge (RWD) and authorizes the SWRCB and RWQCBs to issue and enforce waste discharge requirements 4.6-3

206 H YDROLOGY AND WATER QUALITY (WDRs), NPDES permits, Section 401 water quality certifications, or other approvals. 3 b. State Water Resources Control Board (SWRCB) In California, the SWRCB has broad authority over water quality control issues for the State. The SWRCB is responsible for developing statewide water quality policy and exercises the powers delegated to the State by the federal government under the CWA. Other State agencies with jurisdiction over water quality regulation in California include the California Department of Health Services (DHS) for drinking water regulations, the California Department of Pesticide Regulation, the California Department of Fish and Game (DFG), and the Office of Environmental Health and Hazard Assessment. Regional authority for planning, permitting, and enforcement is delegated to the nine RWQCBs. The regional boards are required to formulate and adopt water quality control plans for all areas in the region and establish water quality objectives in the plans. The City of Walnut Creek is within the jurisdiction of the San Francisco Bay RWQCB (Region 2). The San Francisco Bay RWQCB adopted a Water Quality Control Plan for the San Francisco Bay Basin (the Basin Plan) that designates beneficial uses, establishes water quality objectives, and contains implementation programs and policies to achieve those objectives for all waters addressed through the Basin Plan. 4 c. California Fish and Game Code The California Department of Fish and Game (CDFG) protects streams, water bodies, and riparian corridors through the streambed alteration agreement 3 Porter-Cologne Water Quality Act s website permitting/porter.html, accessed December 23, San Francisco Bay RWQCB, 2007, Water Quality Control Plan (Basin Plan) for the San Francisco Bay Basin, accessed on November 10,

207 HYDROLOGY AND WATER QUALITY process under Section 1601 to 1606 of the California Fish and Game Code. The Fish and Game Code stipulates that it is unlawful to substantially divert or obstruct the natural flow or substantially change the bed, channel or bank of any river, stream or lake without notifying the CDFG, incorporating necessary mitigation and obtaining a streambed alteration agreement. CDFG s jurisdiction extends to the top of banks and often includes the outer edge of riparian vegetation canopy cover. d. SWRCB Construction General Permit ( DWQ) Construction activities that disturb one or more acres of land that could impact hydrologic resources must comply with the requirements of the SWRCB Construction General Permit ( DWQ, adopted on September 2, 2009, and effective July 1, 2010). Under the terms of the permit, applicants must file a complete and accurate Notice of Intent with the SWRCB. Applicants must also demonstrate conformance with applicable best management practices (BMPs) and prepare a Storm Water Pollution Prevention Plan (SWPPP), containing a site map that shows the construction site perimeter, existing and proposed buildings, lots, roadways, stormwater collection, and discharge points, general topography both before and after construction, and drainage patterns across the project site. The operative Construction General Permit ( DWQ), requires stormwater pollution prevention controls, including the imposition of minimum BMPs and the development and implementation of Rain Event Action Plans for certain sites. e. The Water Conservation Act of 2009 (Senate Bill X7 7 (2009)) 5 New mandatory requirements, per state law (SB-X7 7), mandate the reduction of per capita water use and agricultural water use throughout the state by 20 percent by accessed January 12, 4.6-5

208 H YDROLOGY AND WATER QUALITY f. State Updated Model Landscape Ordinance (Assembly Bill 1881 (2006)) 6 The updated Model Landscape Ordinance requires cities and counties to adopt landscape water conservation ordinances by January 31, 2010 or to adopt a different ordinance that is at least as effective in conserving water as the updated Model Ordinance (MO). The City of Walnut Creek adopted its own Water Conservation Ordinance, which the City Council found to be at least as effective in conserving water as the updated MO, on February 7, g. Sanitary District Act of 1923 The Sanitary District Act of 1923 (Health and Safety Code Section 6400 et seq.) authorizes the formation of sanitation districts and enforces the Districts to construct, operate, and maintain facilities for the collection, treatment, and disposal of wastewater. 7 The Act was amended in 1949 to allow the Districts to also provide solid waste management and disposal services, including refuse transfer and resource recovery. Walnut Creek is within the Central Contra Costa Sanitary District, which is discussed in further detail in chapter 4.12, Utilities and Service Systems, of this Draft EIR. 3. Local Regulations a. Contra Costa County Regulations i. Contra Costa Clean Water Program Together with 18 other incorporated cities in Contra Costa County, Walnut Creek has joined with the Contra Costa Flood Control & Water Conservation District and the County in the Contra Costa Clean Water Program (CCCWP) initiative. Members of the program are regulated waste dischargers under an NPDES Permit issued by San Francisco Bay RWQCB, and are responsible for municipal storm drain systems and watercourses that they own or operate. As part of the permitting process, dischargers must submit a Stormwater Management Plan that describes a framework for management of 6 accessed January 12, California Health and Safety Code, calawquery?codesection=hsc, accessed on November 18,

209 HYDROLOGY AND WATER QUALITY stormwater discharges during the term of the permit. 8 Additionally, members are subject to Provision C.3, New Development and Redevelopment Performance Standards, and have developed a Hydromodification Management Plan (HMP) to reduce the hydromodification impacts of stormwater discharges from certain development projects within their jurisdictions. ii. Contra Costa County Flood Control and Water Conservation District The mission of the Contra Costa County Flood Control and Water Conservation District (FC District) is to provide flood protection facilities while protecting environmental resources. 9 The FC District carries out its responsibility by planning and constructing the major storm drainage facilities in Flood Control Zones (entire watershed areas) and in Drainage Areas (subwatershed areas). The FC District collects, analyzes, and reports on rainfall and storm runoff data from a system of rain gauges and several stream flow meters. b. City of Walnut Creek Policies and Regulations i. General Plan 2025 General Plan 2025 contains the following goals, policies, and actions related to hydrology and water quality: Policy Require that commercial projects comply with the City s performance standards for fire, police, parks, water, flood control, and sanitary sewer facilities. Chapter 4 GOAL 32. Meet or exceed State and federal water-quality standards. Policy Support regional, State, and federal clean water efforts. Action Implement the Stormwater Management Plan. 8 Contra Costa Clean Water Program, permits.html, accessed on November 10, Contra Costa County Flood Control District, accessed on November 10,

210 H YDROLOGY AND WATER QUALITY Action Enforce the National Pollution Discharge Elimination System (NPDES) permit regulations. Action Seek Regional Water Quality Control Board NPDES exemptions for low- and moderate income housing and transit village projects. Action Prohibit development in areas particularly susceptible to erosion and sediment loss. Action Prepare information-and-action handouts on water-quality best management practices and provide this information with project application packets. Policy In redevelopment projects in the Core Area, evaluate the desirability of specific, off-site, source-control measures. Policy Maximize infiltration of rainwater into the soil, where appropriate. Action Reduce the amount of impervious surfaces in new development and redevelopment. Action Require that impervious surfaces not drain directly into storm drains. Policy Reduce the transport of urban runoff and surface pollutants offsite. Action Verify the effectiveness of stormwater treatment facilities. Action Verify, through the commercial, industrial, and illicit discharge inspection programs, that interior floor drains are connected to the sanitary sewer system. Policy Encourage preservation of natural water bodies and drainage systems

211 HYDROLOGY AND WATER QUALITY Action Retain natural water bodies and leave drainage systems undisturbed while allowing construction of adjacent creek walks. Action Prioritize onsite impacts and their mitigations. Action Require participation in offsite or regional programs including stream restoration that provide water-quality benefits within the same watershed, wherever development and/or redevelopment projects disturb natural water bodies or drainage systems. Policy Reduce pollutant loading in the wastewater system. Action Apply best-management practices to discharges to the sanitary sewer. Action Establish a pesticide-reducing protocol for city parks. ii. Walnut Creek Municipal Code a) Flood Damage Prevention Title 9, Chapter 12 of the Walnut Creek Municipal Code establishes flood damage prevention measures, which seek to promote the public health, safety, and general welfare, and to minimize losses due to flooding. This ordinance restricts or prohibits uses that are dangerous due to water or erosion hazards or result in damaging increases in erosion, flood heights, or velocities. The ordinance also includes provisions for controlling alteration of natural protective barriers, such as floodplains and stream channels, and development activities, such as filling, grading, and dredging. The construction of flood barriers, which unnaturally divert flood waters or increase flood hazards in other areas, is also restricted or prohibited. b) Stormwater Management and Discharge Control Title 9, Chapter 16 of the Walnut Creek Municipal Code establishes stormwater management and discharge control measures to protect and enhance the 4.6-9

212 H YDROLOGY AND WATER QUALITY water quality in the City of Walnut Creek s watercourses pursuant to the Porter-Cologne Water Quality Control Act. The ordinance is intended to minimize non-stormwater discharges and pollution caused by stormwater runoff from development. Discharges to the City s stormwater system from spills, dumping, or disposal of materials are also regulated. This ordinance specifies the conditions under which C.3-compliant stormwater control plans and SWPPPs must be prepared and implemented. B. Existing Conditions 1. Hydrology of the Project Site and Surrounding Area The Project site is located within the Walnut Creek watershed as shown in Figure The Project site is almost entirely developed with impervious surfaces and stormwater drains into the City s storm sewer system through multiple inlets located throughout the Project site. The City s storm sewer system, in turn, drains into Walnut Creek, approximately 0.5 miles to the east of the site, and eventually discharges into Suisun Bay, 10.5 miles to the north. Other major water bodies in the vicinity of the Project site include Mallard Reservoir, located approximately 7.5 miles to the north of the site, Briones Reservoir, approximately 7 miles to the west, and Lafayette Reservoir, approximately 4 miles to the southwest of the site. On average, the Walnut Creek receives 21 inches of rain annually, with the majority of the rainfall occurring between October and April. 10 Analysis of long-term precipitation records indicate that wetter and drier cycles lasting several years are common in the region. More severe rainstorms occur approximately once every three years. 10 Contra Costa County Flood Control and Water Conservation District, General Hydrologic Analysis Procedures

213 HYDROLOGY AND WATER QUALITY Pleasant Hill Pine Creek Concord BART Treat Blvd Walnut Creek Watershed Project Site Geary Road I-680 N Main St Civic Dr Walnut Creek Heather Farm Bancroft Rd Ygnacio Valley Rd Walnut Ave Oak Grove Rd Pine Creek Galindo Creek Watershed Boundary Oak Lime Ridge Open Space Castle Rock Rd Hwy 24 BART Walnut Blvd Little Pine Cr eek Lafayette Olympic Blvd San Ramon Creek Watershed Shell Ridge Open Space Rudgear Rd Tice Valley Blvd Las Trampas Creek Watershed I-680 Creek Rossmoor Pkwy Creek Watershed Boundary Highways Major Roads NORTH Miles Alamo City Limit Walnut Creek Sphere of Influence Source: Walnut Creek General Plan 2025 EIR, FIGURE WATERSHEDS IN THE VICINITY OF THE PROJECT SITE

214 H YDROLOGY AND WATER QUALITY The Project site is situated over the Ygnacio Valley Groundwater Basin. The primary groundwater units in the basin consist of Quaternary Alluvium. Aquifers in the basin are hydrologically connected to the Sacramento River. 11 Exploratory borings performed by Kleinfelder (2006 and 2004) 12,13,14 indicate that groundwater beneath the Project site ranges in depth from between approximately 15 to 30 feet below ground surface, with the shallowest depth to groundwater in the northwestern portion of the site. 2. Water Quality Stormwater runoff is the principal source of pollution entering surface and ground waters in the San Francisco Bay region. 15 During periods of heavy precipitation, stormwater carries pollutants and sediments into streams, rivers, reservoirs, or marshes either directly or via storm sewer systems. Nonstorm discharges, including irrigation water, accidental spills, and washdown water, also pick up sediments and contaminants from land surfaces and transport these pollutants into surface and ground water. Typical pollutants include oil, grease, or antifreeze leaking from cars or trucks; paint or paint products; leaves or yard waste; pesticides, herbicides, or fertilizers from yards and gardens; solvents and household chemicals; animal wastes, litter, or sewer leakage; and construction debris such as fresh concrete, mortar, or cement. 11 SECOR International Inc., Phase 1 Environment Site Assessment for B.R.E. Properties, Inc., and Walnut Creek Transit Village Lifestyle Associates, LLC. See Appendix D of this Draft EIR. 12 Kleinfelder, Inc., Preliminary Geotechnical Investigation Report, Pinnacle at Walnut Creek Apartments, Walnut Creek, California, File No /RPT. 13 Kleinfelder, Inc., Preliminary Geotechnical Investigation Report, BART Transit Village East Parcel, Walnut Creek, California, File No /GEO. See Appendix C of this Draft EIR. 14 Kleinfelder, Inc., 2006a. Status of Soil and Groundwater Sampling and Testing for Sulfides and Sulfates, BART Transit Village, Walnut Creek, California, File No /GEO. See Appendix C of this Draft EIR. 15 San Francisco Bay Conservation and Development Commission, Final Staff Report, Water Quality Protection and Nonpoint Source Pollution Control in San Francisco Bay, page

215 HYDROLOGY AND WATER QUALITY The Project site is located in the Core Area of Walnut Creek, a highly urbanized environment with substantial areas of impervious surface, including roadways, parking lots, roofs, and buildings. Generally in the Core Area, stormwater runoff flows into the storm drain system and is directed northward, through channels and culverts, eventually discharging into Suisun Bay. Runoff is not treated in the storm sewer system prior to discharge, and therefore stormwater can potentially convey pollutants to Suisun Bay. Suisun Bay is included on the most recent EPA 303(d) list of water quality limited segments, and Total Maximum Daily Loads (TMDLs) have been developed for a variety of pollutants, including furan compounds, mercury, nickel, PCBs, chlordane, DDT, and dieldrin. 16 TDMLs establish the maximum amount of a given pollutant that can enter a waterbody without exceeding water quality standards set pursuant to applicable federal and State regulations. 17 TDMLs are implemented through NPDES permits issued to point source dischargers, such as municipal storm drain systems and publicly owned treatment works. 3. Flooding Flooding in Walnut Creek has primarily been caused by the combination of heavy winter rains and drainage facilities with limited conveyance capacity. The greatest flood damage was caused by a flood which occurred on April 2, 1958, when over 4 inches of rainfall was recorded during a two-day period on already saturated soils. Areas of the City subject to historic flooding include areas along Walnut Creek, Las Trampas and Grayson-Murderers creeks, and San Ramon creek, primarily at the confluence of these waterways in the downtown area. Over the years, most of the creeks and major flood control facilities in Walnut Creek have been improved to adequately handle the State Regional Water Quality Control Board, The 303(d) List of Impaired Water Bodies, programs/tmdls/303dlist.shtml, accessed on June 7, United States Environmental Protection Agency, Total Maximum Daily Loads (303d), ater.epa.govllaw sregellaw sguldancelcw altjrdvovervlew oflrrdl.cfm, accessed on June 7,

216 H YDROLOGY AND WATER QUALITY year floods (defined as a runoff event with a 1 percent annual chance of occurring in any particular year, or an anticipated frequency of once every 100 years). The Project is not located in a General Plan 2025-designated Flood Prone Area, as shown in Figure The current Flood Insurance Rate Map (FIRM) prepared by the Federal Emergency Management Agency (FEMA) shows the area of the Project as Zone X, an area determined to be outside of the 0.2 percent annual chance floodplain. The proposed Project is not located within an identified dam failure inundation hazard area as shown in Figure The elevation of the area and distance from Suisun Bay preclude potential inundation by coastal hazards such as tsunamis, extreme high tides, or future sea level rise. C. Standards of Significance The proposed Project would result in significant adverse impacts if it would: 1. Violate any water quality standards or waste discharge requirements. 2. Substantially deplete groundwater supplies 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). 3. Substantially alter the existing drainage 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, siltation, or flooding on- or off-site. 18 Association of Bay Area Governments, DamInundation/, accessed on December 28,

217 Buena Vista Ave CITY OF WALNUT CREEK HYDROLOGY AND WATER QUALITY Pleasant Hill Pine Creek Concord BART Treat Blvd Project Site Geary Road I-680 N Main St Civic Dr Walnut Creek Heather Farm Bancroft Rd Ygnacio Valley Rd Oak Grove Rd Walnut Ave Boundary Oak Lime Ridge Open Space Castle Rock Rd Hwy 24 Little Pine Cr eek BART Lafayette Walnut Blvd Olympic Blvd Shell Ridge Open Space Rudgear Rd Tice Valley Blvd I-680 Rossmoor Pkwy NORTH Alamo Miles 100-Year Flood Zones Natural creek Channel Highways Major Roads City Limit Walnut Creek Sphere of Influence Source: Walnut Creek General Plan 2025 EIR, FIGURE FLOOD PRONE AREAS

218 HYDROLOGY AND WATER Martinez AB 242 Concord AB 242 Pleasant Hill Clayton Project Site 680 Lafayette Walnut Creek Dam Failure Inundation Areas Areas that can be inundated by any one of: 5 different dams 4 different dams. Moraga 3 different dams 2 different dams 1 dam only Urbanized Area Danville NORTH Source: ABAG, Shaded to show topographical relief FIGURE DAM FAILURE INUNDATION Scale: 1 inch HAZARD = 1.34 miles AREA

219 HYDROLOGY AND WATER QUALITY 4. Create or contribute runoff water, which would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff. 5. Otherwise substantially degrade water quality. 6. Place housing within a 100-year flood hazard area as mapped on a Federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map. 7. Place within a 100-year flood hazard area structures which would impede or redirect flood flows. 8. 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. 9. Inundation by seiche, tsunami, or mudflow. D. Impact Discussion 1. Violate any water quality standards or waste discharge requirements. The Project would have a significant environmental impact if it would violate water quality standards and waste discharge requirements set out in NPDES Permit CA , issued to CCCSD, or the Municipal Regional Stormwater NPDES Permit (CAS612008) in force for Walnut Creek. Violation could occur if the Project would substantially increase pollutant loading levels in the sanitary sewer system, either directly, through the introduction of pollutants generated by industrial or other land uses, or indirectly, through stormwater pollution. According to the terms of NPDES permit CA , the CCCSD implements and enforces a pretreatment program for effluent discharged into Suisun Bay. CCCSD also complies with the RWQCB Monitoring and Reporting Program and administers a Pollutant Minimization Program for ongoing reductions in pollutant loadings to the treatment plant and the receiv

220 H YDROLOGY AND WATER QUALITY ing waters. The Project would involve construction and operation of residential and commercial uses and would not involve industry likely to substantially increase pollutant loading levels in the sanitary sewer system. Additionally, in compliance with the SWRCB Construction General Permit and the Walnut Creek Municipal Code, a SWPPP would be prepared for the Project detailing the methods for preventing the pollution of stormwater with sediment, petrochemicals, or other pollutants associated with construction activities or equipment. Further, implementation of Municipal Regional Stormwater NPDES Permit Provisions C.3 BMPs described in chapter 3 of this EIR, including bio-swales, flow-through planters, and permeable paving treatments throughout the Project site, would provide natural filtration of stormwater, reducing the volume of contaminants entering the City's storm sewer system. Therefore, development of the Project would not violate established water quality standards or waste discharge requirements. A less-than-significant impact would result. 2. Substantially deplete groundwater supplies 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. The Project would have a significant environmental impact if it would result in a net deficit in aquifer volume or a lowering of the local groundwater table level. The Project would not draw on groundwater to supply the proposed residential and commercial uses, relying instead on East Bay Municipal Utilities District (EBMUD) water supplies sourced primarily from the Mokelumne River. Given the shallow depth to groundwater in the northwestern Phase II portion of the site, temporary dewatering activities would likely be required subject to issuance of permits from the RWQCB. Post-construction, a basement-level, under-slab drainage layer would be constructed and, subject to a RWQCB dewatering permit, groundwater seepage would be removed with sumps would be used to prevent hydrostatic uplift

221 HYDROLOGY AND WATER QUALITY Additionally, as described in chapter 3 of this EIR, the Project would include a variety of stormwater management features, such as bio-retention areas, flow-through planters, and permeable pavers, which would allow for natural filtration and improved groundwater recharge in comparison to existing conditions. As such, compliance with applicable dewatering and C.3 regulations would ensure that development of the Project would result in a less-thansignificant impact to groundwater resources. 3. Substantially alter the existing drainage 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, siltation, or flooding on- or off-site. The Project would result in a significant environmental impact if it would require modifications to drainage patterns that could to lead to substantial erosion of soils, siltation, or flooding. Such drainage pattern changes could be caused by grade changes, the exposure of soils for periods of time during which erosion could occur, or alterations to creekbeds. The Project would not involve the direct modification of any watercourse; however, grading and excavation would be required to prepare the site for construction of the Project. Pursuant to the SWRCB Construction General Permit, a SWPPP would be prepared and implemented for the Project to ensure that erosion, siltation, and flooding are prevented to the maximum extent practicable during Project construction. Additionally, compliance with provisions of the Walnut Creek Municipal Code pertaining to grading and excavation would further reduce the potential for erosion, siltation, and flooding as a result of construction activities. As explained in chapter 3 of this EIR, at buildout, the Project would provide a network of bio-retention areas, flow-through planters, and permeable pavers throughout the site. Compliance with C.3 standards for stormwater treatment and the applicable provisions of the Walnut Creek Municipal Code would ensure that post-construction runoff volume and velocity do not exceed pre-construction levels. Additionally installation of the proposed

222 H YDROLOGY AND WATER QUALITY stormwater treatment facilities would improve infiltration and natural drainage on the site, thereby reducing the potential for erosion, siltation, or flooding. Overall, construction and operation of the Project would not result in substantial erosion, siltation, or flooding either on- or off-site and associated impacts would thus be less than significant. 4. Create or contribute runoff water, which would exceed the capacity of existing or planned stormwater drainage systems or provide substantial additional sources of polluted runoff. Prior to commencement of construction activities, a SWPPP would be drawn up to comply with the requirements of the SWRCB Construction General Permit. Implementation of the SWPPP would ensure adverse impacts related to stormwater pollution from Project construction activities would be less than significant. Provision C.3 of San Francisco Bay Region NPDES Permit requires that developments creating or replacing 1 acre of impervious surface detain or infiltrate runoff so that peak flows and durations match pre-project conditions. As described in Chapter 3 and shown in Figure 3-10, the Project would include various stormwater management features, such as bio-retention areas, flow-thru planters, and pervious pavers. The total amount of stormwater treatment area would exceed that required for compliance with the C.3 provisions. Most of the existing site is currently impervious, consisting primarily of paved parking areas. The Project would reduce the total amount of impervious surface and correspondingly reduce the volume of run-off flowing into the storm sewer system. As such, adverse impacts related to stormwater capacity and pollution from Project operation would also be less than significant. 5. Otherwise substantially degrade water quality. The principal source of water pollutants from the Project would be stormwater runoff containing lawn chemicals or petrochemicals from roadways on

223 HYDROLOGY AND WATER QUALITY the Project site. As described above, the Project would provide a network of bio-retention areas, flow-through planters, and permeable pavers throughout the site in compliance with the stormwater control provisions of the Contra Costa County Clean Water Program and the Walnut Creek Municipal Code. Implementation of these stormwater management BMPs would increase the total area available on-site for stormwater treatment in comparison to existing conditions and provide more natural filtration of pollutants from stormwater runoff before it enters the storm sewer system. As such, buildout of the Project would improve the treatment of stormwater on-site and reduce stormwater pollution on-site. Therefore, impacts would be less than significant. 6. Place housing within a 100-year flood hazard area as mapped on a federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map. As described above, the Project site is not located within a 100-year Flood Zone, as identified by FEMA or General Plan ,20 As a result, no impact would occur. 7. Place within a 100-year flood hazard area structures which would impede or redirect flood flows. As described above, the Project site is not located within a 100-year Flood Zone, as identified by FEMA or General Plan ,22 As a result, no impact would occur. 19 FEMA Flood Map, 06013C0289F. 20 Walnut Creek General Plan 2025, Safety, and Noise Element, Figure 5, Flood Zones. 21 FEMA Flood Map, 06013C0289F. 22 Walnut Creek General Plan 2025, Safety, and Noise Element, Figure 5, Flood Zones

224 H YDROLOGY AND WATER QUALITY 8. 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. As shown on Figure 4.6-3, the Project site is not located in a dam failure inundation hazard area. The closest dam to the Project site is the Lafayette Reservoir Dam, located roughly 4 miles to the southwest. A two-phase safety review conducted between 2005 and 2008 demonstrated that the dam is stable and safe for both long-term static and short-term seismic conditions, including the Maximum Credible Earthquake (MCE). The risk of dam failure is therefore very low, and as a result, impacts from buildout the proposed Project would be less than significant. 9. Inundation by seiche, tsunami, or mudflow. The Project site is not located close to a large body of water, tidal or otherwise, that could result in inundation by seiche or tsunami. The Project site is located approximately 27 miles east of the Pacific Ocean, approximately 14 miles east of San Francisco Bay, and more than 10 miles south of Suisun Bay. The closest large body of water is the Lafayette Reservoir, located roughly 4 miles to the west of the Project site. Given its distance from these bodies of water, the Project site is not at risk of inundation in the event of tsunami or seiche. Additionally, as detailed in chapter 4.4 of this EIR, there are no slopes with gradients of 15 percent or more on or adjacent to the Project site. As such, the Project site is not at risk of inundation in the event of mudslide. Overall, buildout of the Project would result in no impact related to inundation by seiche, tsunami, or mudslide. E. Cumulative Impacts This section analyzes potential cumulative impacts to hydrology and water quality that could occur from a combination of the proposed Project with other reasonably foreseeable projects in the surrounding area. The geographic scope of this analysis is taken to be the Walnut Creek Watershed. Cumulative impacts would be significant if development associated with the Project together with other projects in the Walnut Creek Watershed would substan

225 HYDROLOGY AND WATER QUALITY tially and adversely affect water quality, increase risk of damage, loss, injury, or death due to flooding, or increase stormwater runoff or erosion. As described above, the proposed Project would not increase stormwater runoff or erosion, put a greater number of people and structures within areas at risk of dam or levee inundation, create new significant impacts associated with the placement of structures in Special Flood Hazard Areas, or result in degraded water quality. Overall, the proposed Project would promote improved water quality on the Project site and in the surrounding area. The Project would therefore not contribute to an associated cumulative impact. Additionally, the aforementioned federal, State, and local regulations would apply equally to all development in the Walnut Creek Watershed, and continued compliance would ensure that cumulative impacts are reduced or avoided to the maximum extent practicable. As such, buildout of the proposed Project together with other cumulative projects in the Walnut Creek Watershed would result in a less-than-significant cumulative impact. F. Impacts and Mitigation Measures The Project would not result in any significant impacts to water quality; therefore, no mitigation measures are necessary

226 H YDROLOGY AND WATER QUALITY

227 4.7 LAND USE AND PLANNING This chapter describes the regulatory framework and existing conditions related to land use in the vicinity of the Project, and the potential land use and policy consistency impacts of the Project. A. Regulatory Framework This section describes land use plans and policies relevant to the proposed Project. 1. Contra Costa County Growth Management Regulations In 1988, Contra Costa County voters approved Measure C, designed to foster cooperation between municipalities and the County on transportation and growth issues that cross city boundaries. Measure C established a countywide half-cent sales tax to be collected for 20 years, through 2008, in order to fund roadway and transportation system improvements. The Contra Costa County Transportation Authority distributes sales tax revenues collected under the measure to jurisdictions that implement the required growth management goals, policies, and actions adopted as part of their general plans. In 2004, County voters approved Measure J, extending the growth management requirements of Measure C through Bay Area Rapid Transit District (BART) Policies a. Transit-Oriented Development (TOD) Policy In 2005, the Bay Area Rapid Transit (BART) District's Board of Directors adopted a Transit-Oriented Development (TOD) Policy that aims to promote high-quality, more intensive development on and near BART stations. BART's TOD Policy articulates the following goals: Increase transit ridership and enhance quality of life at and around BART stations by encouraging and supporting high quality transitoriented development within walking distance of BART stations. Increase transit-oriented development projects on and off BART property through creative planning and development partnerships with local communities

228 LAND USE AND PLANNING Enhance the stability of BART s financial base through the value capture strategies of transit-oriented development. Reduce the access mode share of the automobile by enhancing multimodal access to and from BART stations in partnership with communities and access providers. 3. City of Walnut Creek Policies and Regulations a. Walnut Creek General Plan 2025 i. General Plan Land Uses General Plan 2025 guides development in Walnut Creek over the course of its 20-year planning horizon. The Built Environment chapter of General Plan 2025 regulates land use within the city limit, establishing specific land use designations to express the desired pattern of development. Two land use designations currently apply to the Project site, as shown in Figure The portion of the site west of the BART tracks is designated Mixed Use Residential Emphasis (MU-R), while the portion to the east of the tracks is designated Public/Semi-Public (PU). The Mixed Use Residential Emphasis designation is intended to encourage ground floor retail uses with residential and/or office space on the floors above. 1 The primary use must be residential, and commercial uses are limited to a maximum floor area ratio (FAR) 2 of 0.3. Allowable FAR for residential uses is from 1.5 to 2.5, which General Plan 2025 determines to be equivalent to a residential population density of between 47.9 to 79.5 people per net acre. The Public/Semi-Public land use designation encompasses facilities serving the general good, including BART stations, the civic center, fire stations, government buildings, libraries, public schools, privately owned communityserving recreational facilities and public 1 City of Walnut Creek, 2006, General Plan 2025, page Floor area ratio (FAR) is an expression of building intensity, indicating the ratio of gross building floor area (excluding areas designated for parking, etc) to net lot area, both expressed in square feet

229 Buena I-68 City CITY of OF Walnut WALNUT Creek CREEK Walnut Creek BART Bart TRANSIT transit VILLAGE Village DRAFT DraF t EIR eir LAND USE AND PLANNING General Plan Land Use Map City of Walnut Creek 2025 Legend Single Family Very Low (SFVL) du/ac Single Family Low (SFL) du/ac Single Family Medium (SFM) du/ac Single Family High (SFH) du/ac Multifamily Low (MFL) du/ac Multifamily Medium (MFM) du/ac Multifamily Medium High (MFMH) du/ac Multifamily Very High (MFVH) du/ac ProJeCt site Multifamily Special High (MFSH) du/ac Mixed Use - Residential Emphasis (MU-R) Density Varies Mixed Use - Pleasant Hill BART Station Area Specific Plan Mixed Use - Commercial Emphasis (MU-C) Density Varies Mixed Use - Golden Triangle (MU-GT) Density Varies Open Space - Agriculture (OS/A) 0.1 du/ac Open Space - Recreation (OS/R) Service Commercial (SC) Auto Sales and Service (AS) General Retail (GR) Public/Semi Public (PU) Hospital (HO) Pedestrian Retail (PR) Office (OF) Business Park (BP) Highways Major Roads City Limit Planning Area Boundary Sphere of Influence The official copy of the General Plan Land Use Map is kept at the Community Development Department and is available to the public during all regular business hours. This is one of several General Plan maps that affect development in Walnut Creek and which should be consulted. The General Plan text is itself an integral part of the land use plan for the city and must also be consulted. The City of Walnut Creek is not responsible for use of this map beyond its General Plan purposes. source: Walnut Creek general Plan 2025 north Miles FIGURE F igure GENERAL PLAN e xisting 2025 LAND l and USE u se DESIGNATIONS d esignations

230 LAND USE AND PLANNING utility stations and yards. 3 The allowable FAR for this land use designation is determined on a case-by-case basis, not to exceed ii. Core Area Building Height Limits In 1985, Walnut Creek voters approved Measure A, the Building Height Freeze Initiative. Measure A established height limits for new development throughout the city, freezing building height based on the operative zoning ordinance on the date the initiative was approved. Measure A height limits are incorporated into General Plan 2025, as well as the City's Planning and Zoning Ordinance, and can be modified only with voter approval. 5 In conformance with Measure A, General Plan 2025 establishes building height limits for the city's Core Area, as shown in Figure Building height limits for residential districts and areas outside the Core Area are established in the Zoning Ordinance. As shown in Figure 4.7-2, a maximum building height of 50 feet presently applies to the portion of the Project site west of the BART tracks. East of the BART tracks, maximum building height is limited to 35 feet; however, the original Measure A limitation, which set as the ceiling the heights established in the Zoning Ordinance as of the date of the Measure s passage, indicated that the maximum height for the entire BART site was 50 feet. iii. Growth Management Program Walnut Creek has had commercial growth management regulations, in various forms, for more than 25 years. Community concern over excessive traffic congestion and the construction of a number of large commercial office buildings in downtown Walnut Creek in the 1970s and 1980s originally prompted the restriction of commercial development in the city. Growth Limitation Implementation Regulations were incorporated into the City's General Plan in 1993, limiting commercial development in the city to no more than 75,000 3 City of Walnut Creek, 2006, General Plan 2025, page City of Walnut Creek, 2006, General Plan 2025, page City of Walnut Creek, 2006, General Plan 2025, page

231 Chapter 4, Built Environment CITY OF WALNUT CREEK LAND USE AND PLANNING I-680 PROJECT SITE North Main St Civic Dr Ygnacio Valley Rd BART North California Blvd Lafayette BART Mount Diablo Blvd Hwy 24 I-680 Olympic Blvd Height Limits (in feet) / BART City Limit Alamo Planning Area Boundary Newell Ave NORTH South Main St ,600 Feet Source: Walnut Creek General Plan 2025, Miles Base Map Data: April 1, 2005 Data Source: City of Walnut Creek Figure 10. Core Area Height Limits Height limits shown in this figure apply to the Core Area only. The height limits found in the Zoning Ordinance apply to residential districts and areas outside the Core Area. FIGURE Walnut Creek General Plan 2025 CORE AREA BUILDING HEIGHT LIMITS April 4, 2006

232 LAND USE AND PLANNING square feet of net new floor area per year, metered in two-year increments. 6 General Plan 2025, adopted by the City Council in 2006, maintained the established limitations on commercial growth. Community facilities serving the public and the larger community good are exempt from the Growth Management Program, as is commercial development within the Shadelands Business Park. iv. Building Setbacks Along specifically designated streets, General Plan 2025 regulates a minimum setback distance from the right-of-way and a minimum amount of open area between the building and the right-of-way. General Plan 2025 requires a moderate setback of between 10 to 20 feet for lots with frontage on Ygnacio Valley Road. A moderate setback is required along North California Boulevard, except for the lots along approximately 400 feet of North California Boulevard from Ygnacio Valley Road to the north, where a major setback of between 20 to 30 feet is required. v. Building Stepbacks General Plan 2025 also regulates building stepbacks in some areas to preserve views of Mount Diablo and surrounding open space areas; however, there are no stepback regulations which apply to the Project site. vi. Goals, Policies, and Actions Relevant General Plan 2025 goals, policies, and actions intended to guide land use in the city are listed below: GOAL 3. Encourage housing and commercial mixed-use development in selected locations that enhances pedestrian access and reduces traffic. 6 City of Walnut Creek, Growth Management Program, accessed on December 1,

233 LAND USE AND PLANNING Action Encourage mixed-use development at and near the Walnut Creek and Pleasant Hill BART Stations. GOAL 5. Require that infill development is compatible with its surroundings. Policy 5.1 Require infill development to be compatible with adjacent and nearby uses. GOAL 8. Allow development consistent with the density ranges of the General Plan 2025 land use map. Policy 8.1 Require that residential projects be developed within the established minimum and maximum density ranges. GOAL 9. Manage the community s orderly growth. Policy 9.1 Mete out the amount of commercial development allowed annually. Action Limit the amount of commercial development permitted citywide, outside of the Shadelands Business Park, to no more than 75,000 square feet per year from 2006 through 2015, allotting no more than 150,000 square feet in any 2-year period. Action Allow unallocated commercial development square footage to be carried over to the next development cycle

234 LAND USE AND PLANNING GOAL 10. Coordinate the location, intensity, and mix of land uses with transportation resources. Policy 10.1 Support the development of medium and high-density office, residential, and local service retail near and around the Walnut Creek and Pleasant Hill BART Stations. Action Apply land use designations that encourage transit oriented development around the BART stations and in the Core Area. Policy 10.2 For specific sites where traffic congestion could be significantly improved and view corridors would not be adversely impacted, consider supporting a change to Measure A height limits. GOAL 11. Create a balanced, safe, and efficient regional and subregional transportation system. Policy 11.2 Implement Measure C and plan for the implementation of Measure J. Action Demonstrate compliance with all components of the Measure C (1988) and Measure J (2004) Growth Management Program. Action At a minimum, comply with the Measure C adopted standards for Level of Service at intersections along Basic Routes. Policy 11.3 Require that new development pay its share of costs associated with growth. GOAL 12. Make more efficient use of the regional and subregional transportation system. Policy 12.2 Support infill and redevelopment in existing urban areas. GOAL 13. Maintain and enhance high quality building design and urban design

235 LAND USE AND PLANNING Action Allow increases in height, up to the Measure A height limits, for developments that provide exceptional public amenities such as accessible roof gardens, ground-level public plazas, creek orientations, public courtyards and passageways, landscaping, public art, and other desired public amenities beyond those specified during the normal City review process. Action For specific sites that offer good potential for mixed-use development (e.g., former Co-op site [1510 Geary Road] or the Palos Verde Mall), facilitate community discussion about increasing the Measure A height limits. 4. Walnut Creek Housing Element The City s adopted Housing Element describes both how Walnut Creek plans to meet the projected housing needs of all economic segments of the community and the City s fair share allocation of regional housing needs. The Housing Element contains policies and programs that pertain to high density urban infill housing such as the proposed Project. The Housing Element also addresses the provision of housing for city residents, including affordable, mixed-use, and infill housing, and includes an analysis of whether Walnut Creek has provided adequate sites to meet its Regional Housing Needs Assessment (RHNA) obligations. The following goals, policies, and actions are contained in the existing Walnut Creek Housing Element: GOAL 1: To promote the availability of housing types for all economic segments of the community consistent with the infrastructure and service capacities of the City. Policy 1: Encourage a mix of land uses and residential densities in the downtown Core Area to increase the supply of housing; Program 1.1: Maintain General Plan designations for highdensity residential housing and Mixed Use Res

236 LAND USE AND PLANNING idential and Mixed Use Commercial districts in the Core Area; Policy 3: Encourage housing and commercial mixed-use development in selected locations that enhances pedestrian access and reduces traffic [sic], particularly in the Core Area, and near public transit. Program 3.1: Develop new zoning designations that are consistent with the newly established Mixed Use Land Use Categories and require that new development includes a residential component in the Mixed Use/Residential Emphasis land use categories. Identify key properties, such as the BART Transit Village, for mixed use development. 7 Policy 10: Provide an adequate supply of residentially zoned land at sufficient densities to accommodate existing and future housing needs. GOAL 2: To encourage energy conservation and green building policies and practices in residential development. Policy 18: Encourage the incorporation of energy conservation design features in existing and future residential development. Policy 19: Encourage the use of sustainable and green building design in new and existing housing in compliance with the legislation in AB32 and SB375 GOAL 3: Strive to meet Walnut Creek's regional housing needs. 7 City of Walnut Creek, 2009, Walnut Creek Housing Element

237 LAND USE AND PLANNING Policy 20: Strive to meet Walnut Creek's share of regional housing needs. Program 20.1: Work to attempt to produce 1,958 dwelling units between January 1, 2007 and June 30, 2014, the City's share of the region's housing needs as estimated by ABAG. 5. City of Walnut Creek Municipal Code a. Zoning Ordinance Contained in Title 10, Chapter 2 of the Walnut Creek Municipal Code, the City's Zoning Ordinance implements the land use goals, policies, and actions established in General Plan The Zoning Ordinance identifies specific zoning districts within the city and describes the development standards that apply to each district. The Project site is zoned Community Facility (CF). Permitted uses under this zoning designation include cultural institutions, colleges and schools, day care facilities, government offices, public transit terminals, and public safety facilities. In the CF district, maximum density is capped at an FAR of 2.0 and actual density is determined on a case-by-case basis in conjunction with the approval of a Conditional Use Permit. Minimum lot area, lot width, frontage, depth, setback, landscaping, and parking requirements are likewise determined in the approval of a Conditional Use Permit. b. Tree Preservation Ordinance The City's Tree Preservation Ordinance, contained in Title 3, Chapter 8 of the Municipal Code, applies to any tree that has a single perennial stem of 28 inches or larger in circumference, or has multiple perennial stems with an aggregate circumference of 40 inches or more, when measured at 4.5 feet above natural grade. Under the ordinance, a tree also includes a tree of any size which is part of a grove. A Tree Removal Permit is required to cut down, destroy, or remove any tree subject to the Ordinance, and in general, tree removal is only permitted when the burden of preserving the tree outweighs the benefit to the public. The Ordinance also establishes measures to protect trees to be preserved on-site during construction activities. Activities

238 LAND USE AND PLANNING such as excavation, construction, or soil compaction within the dripline of a tree protected by the ordinance require a Dripline Encroachment Permit. Additionally, the Ordinance designates the following species as Highly Protected Trees: Valley oak, blue Oak, coast live oak, California black oak, canyon live oak, interior live oak, madrone, California buckeye, California black walnut, and grey pine. The removal of a Highly Protected Tree can be authorized only if the burden to the applicant in preserving the tree would greatly outweigh the benefit to the public and if preserving the tree would severely reduce the scale or feasibility of the development. 6. Public Art Master Plan The Public Art Master Plan provides guidelines for public art in Walnut Creek and is intended to encourage the inclusion of public art in development projects. The Master Plan identifies public art zones throughout the city, discusses the roles of the Design Review Commission and Art Commission, identifies criteria and processes to be used in the selection of artwork, and recommends funding sources. The Master Plan envisions artworks such as fountains, large-scale sculpture, or landscape elements integrated into plaza areas, building exteriors, or streetscapes in the Core Area, where the Project site is located. The Project site is identified as a priority site in the Public Art Master Plan. The City has adopted a Public Art Ordinance, Title 10, Chapter 10 of the Walnut Creek Municipal Code, which requires payment of a public art fee in the amount of one percent of the construction cost of the completed development project for all private development projects in the Core Area of 25,000 square feet or more, or installation of public art on-site. 7. City of Walnut Creek 2011 Bicycle Plan The City s 2011 Bicycle Plan is discussed in Chapter 4.11, Transportation and Parking, of this Draft EIR

239 LAND USE AND PLANNING B. Existing Conditions 1. Surrounding Land Uses and Context The proposed Project site occupies a strategic location in Walnut Creek and serves as a gateway to the community. With the Walnut Creek BART station and a Central Contra Costa Transit Authority (CCCTA) bus terminal onsite, it plays a role as a transportation hub, providing easy access to downtown and the office buildings of the Golden Triangle. a. North of the Project Site Located immediately to the north of the proposed Project site is a cluster of high-rise office buildings and smaller businesses built in the 1980s, known as the Golden Triangle. Collectively, these buildings house approximately 1.7 million square feet of leasable space and account for 23 percent of the total available market for office space in Walnut Creek. 8 b. East of the Project Site Across North California Boulevard, to the east of the Project site, is another cluster of office buildings (Ygnacio Center). South of these buildings, and southeast of the Project site, is a large retail store. c. South of the Project Site The area immediately to the south of the proposed Project site, across Ygnacio Valley Road, contains residences, offices and a gas station. Further south, is an area of single-family homes, rental apartments, and offices. The Walnut Creek Presbyterian Church is also located in this area, at 1801 Lacassie Avenue, as is St. Paul s Episcopal Church, at 1924 Trinity Ave. d. West of the Project Site Interstate 680 (I-680) runs parallel to the western perimeter of the site, and farther to the west, on the opposite side of the freeway, are residential neigh- page AECOM, January 2009, Draft Walnut Creek Transit Village Market Study,

240 LAND USE AND PLANNING borhoods characterized by duplexes and single-family homes, as well as a Seventh Day Adventist church. 2. Existing Uses on the Project Site The proposed Project site comprises 16.5 acres of land in the Core Area of Walnut Creek. At the center of the site lies the Walnut Creek BART station, completed in In addition to the station amenities inside the fare gates, the station complex includes a BART Police substation, a ticket office, and bicycle parking pods. The elevated BART tracks bisect the site from southwest to northeast, and there is an 11-bay CCCTA bus terminal on-site to the east of the BART tracks. The remainder of the site is given over to parking facilities, including a four-level parking structure (three stories with podium parking on the roof) to the west of the station, as well as four surface parking lots. There is an internal roadway linking the on-site parking areas with the four driveways around the periphery of the site. 3. Existing Trees A Tree Survey Plan, prepared by Guzzardo Partnership, Inc., identified 69 existing trees on the Project site. The trees were classified according to their suitability for preservation based on size, species, and condition. Twentyeight are listed as Good, 27 Moderate, and 14 Poor. Three of the 69 trees are Highly Protected Trees, all of which are Valley oaks. As described in Chapter 3, Project Description, of this EIR, these three trees would be preserved on the Project site. C. Standards of Significance The proposed Project would result in a significant land use impact if it would: 1. Physically divide an established community. 2. Conflict with any applicable land use plan, 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 ordi

241 LAND USE AND PLANNING nance) adopted for the purpose of avoiding or mitigating an environmental effect. 3. Conflict with any applicable habitat conservation plan or natural community conservation plan. D. Impact Discussion 1. Physically divide an established community. As described above, the proposed Project site is currently dominated by parking facilities and bisected by the elevated BART tracks. There are residential neighborhoods west of Interstate 680 and to the south across Ygnacio Valley Road. The proposed Project would not divide an existing community as the surrounding neighborhoods are already separated from the Project site by Interstate 680 and arterial roads, and the proposed Project would not exacerbate this separation. Many of the features proposed by the Project would improve linkages with surrounding uses. The residences and shops to be housed in the mixed use buildings of the proposed Project would provide greater continuity of development in the area, and the pedestrian paseos, the public plazas and the crosswalk on North California Boulevard would create a more inviting pedestrian environment for people as they move to and from the site in all directions. As a result, the proposed Project would result is a less-than-significant impact on the division of an established neighborhood. 2. Conflict with any applicable land use plan, policy or regulation of an agency with jurisdiction over the Project (including, but not limited to the general plan, specific plan or zoning code) adopted for the purpose of avoiding or mitigating an environmental effect. a. Contra Costa County Regulations As described above, Contra Costa County voters approved Measure C and Measure J in 1988 and 2004, respectively, to fund roadway and other transportation improvements. The construction and operation of the proposed Project would increase funds from the sales tax generated at uses on the Project site. Implementation of growth management goals, policies, and actions

242 LAND USE AND PLANNING specified by the County is a prerequisite for receipt of Measure C/J funding. Walnut Creek fulfills these requirements through Goals 11 and 12 of the Built Environment chapter of General Plan Policies and actions related to transportation and Measures C and J are discussed in Chapter 4.11, Transportation and Parking. b. BART Transit-Oriented Development Policy As described in Section A2 above, BART's TOD Policy seeks to promote high-quality, more intensive development on and near BART stations. The proposed Project is consistent with the TOD Policy because it would locate 596 dwelling units immediately adjacent to the Walnut Creek BART station and because many of its future residents would be expected to ride BART for commute or recreational trips instead of driving. c. Walnut Creek General Plan 2025 As discussed above, the western portion of the proposed Project site is designated Mixed Use Residential Emphasis (MU-R), while the portion to the east of the BART tracks is designated Public/Semi-Public use in the Walnut Creek General Plan. The applicant has requested a General Plan Amendment to change the land use designation for the site to extend the Mixed Use Residential Emphasis designation to the whole of the Project site. The proposed Project is consistent with Goal 3 of the General Plan, which seeks to encourage housing and commercial mixed-use development in the vicinity of the Walnut Creek BART station. The Project is also consistent with General Plan 2025 Goal 5, requiring that infill development be compatible with its surroundings; Goal 9, calling for orderly growth management; and Goals 11 and 12, calling for a balanced, safe, and efficient regional and sub-regional transportation system. The Project is also consistent with General Plan Policy 18.1, which seeks to preserve and enhance urban connections to scenic views. As discussed in response to criteria 2 in Chapter 4.1, Aesthetics, the proposed design of the East

243 LAND USE AND PLANNING Buildings would preserve a scenic view eastward from the BART platform that would result in a less-than-significant impact to scenic views. d. Walnut Creek Housing Element The City's adopted Housing Element describes how Walnut Creek plans to meet the projected housing needs of all economic segments of the community and the City s fair share allocation of regional housing needs. The Housing Element includes the policies listed in Section A.4., above, that pertain to high-density urban infill housing such as the proposed Project. The Housing Element also addresses the provision of housing for city residents, including affordable, mixed-use, and infill housing, and includes an analysis of whether Walnut Creek has provided adequate sites to meet its Regional Housing Needs Allocation (RHNA) obligations. The proposed Project is consistent with Policy 1 and Program 1.1 of the Housing Element because it proposes a variety of housing types within the Project site. As discussed in the Project Description of this EIR, the Project would comply with the City s Inclusionary Housing Ordinance, which currently requires payment of an in-lieu fee for rental apartments or other measures deemed by the City to be in compliance with the Ordinance. Alternatively, the Project Applicant may propose to include affordable units onsite in exchange for a direct financial contribution from the City or a form of assistance specified in Chapter 4.3 (commencing with Section 65915) of Division 1 of Title 7 of the Government Code. In this case, the applicant has requested to pay in-lieu fees instead of providing affordable units. The in-lieu fee is $15 per square foot of residential space. The proposed Project is consistent with Policy 3 of the Housing Element because it proposes higher density residential and commercial mixed-use development in the Core Area of downtown Walnut Creek. The proposed Project site is located in the Core Area, at the intersection of two major thoroughfares (Ygnacio Valley Road and North California Boulevard), and is located adjacent to Interstate 680 and the existing Walnut Creek BART station. It proposes to offer ample pedestrian access and is located in a

244 LAND USE AND PLANNING regional transit hub. The proposed Project is also consistent with Program 3.1, which specifically identifies the BART Transit Village as a key property for mixed use development. The proposed Project is consistent with Policy 10 of the Housing Element insomuch as it seeks a rezone from Community Facilities to a Planned Development in order to host a mixed-use development with a residential emphasis. This change would thus facilitate the furtherance of Policy 10, to provide an adequate supply of residentially zoned land at sufficient densities to accommodate existing and future housing needs. The proposed Project conforms to Goal 2 and subsequent Policies 18 and 19 of the Housing Element because it would be required to be constructed in accordance with the 2010 California Green Building Standards Code, as adopted in Title 9, Chapter 21, of the Walnut Creek Municipal Code, and landscaped in accordance with the City s Water Efficient Landscaping Ordinance, as set forth in Title 10, Chapter 2, of the Walnut Creek Municipal Code. In adhering to these ordinances and codes, the proposed Project would realize the shared vision of these facets of the Housing Element, which look to encourage energy conservation and green building practices in residential development. The proposed Project is consistent with Goal 3, Policy 20, and Program 20.1 of the Housing Element because it proposes 596 residential units in Walnut Creek that would count towards fulfilling the construction of the City s share of regional housing needs. As discussed in Chapter 4.9, Population, Housing, and Employment, of this Draft EIR, the proposed Project would increase the number of dwelling units located within the city without displacing existing dwelling units or residents. The proposed Project would not conflict with the Housing Element and would result in a less-than-significant impact

245 LAND USE AND PLANNING e. Zoning Ordinance The entire Project site is currently zoned as a Community Facility in the Zoning Ordinance. The Zoning Ordinance sets the maximum allowable height of buildings at 50 feet for the portion of the site west of the BART line, and caps heights at 35 feet on the portion of the site east of the BART line. As noted in the Title 10 of the Municipal Code, antennas, chimneys, mechanical equipment, and small architectural element are not to be included as building height provided they do not exceed a height of twelve feet above the roof, and when combined, do not occupy more than twenty-five percent of the horizontal roof area. 9 The purpose of the public/semi-public designation and the 35-foot height limit on the eastern portion of the proposed Project site was to prevent potential blockage of scenic vistas from the BART platform looking east toward the mountains. However, the height limit of 50 feet established by Measure A takes precedence over the heights set in the current Zoning Ordinance. The applicant has requested that the entire property be re-zoned to Planned Development so as to allow the specific uses and site configuration proposed. Figure shows the elevation of the proposed buildings in relation to the 50-foot Measure A height limit applicable to the Project site. As shown, the roofs of the buildings would not exceed the 50-foot limit. Additionally, rooftop appurtenances would not occupy more rooftop area than allowed or extend more than 12 feet above roof level. Further, as described in Chapter 4.1 of this EIR, design of the Project would preserve scenic views of Mount Diablo from the BART platforms. Consequently, the proposed Project would not conflict with the Zoning Ordinance and would result in a less-thansignificant impact. f. Tree Preservation Ordinance Pursuant to the Tree Preservation Ordinance, the applicant has submitted a Tree Survey Plan and applied for a Permit to remove 66 trees from the Project site. The three Highly Protected Valley oaks would remain on-site and 9 City of Walnut Creek Municipal Code, Title 10, Section , 39b

246 LAND USE AND PLANNING 50 HEIGHT LIMIT EXHIBIT Source: MVE & Partners, FIGURE PROPOSED BUILDING HEIGHTS IN RELATION TO MEASURE A LIMITS

247 LAND USE AND PLANNING would require protection in full compliance with the Ordinance during the construction period. The Walnut Creek Tree Preservation Ordinance describes the required actions necessary to protect the existing trees during the construction period. Actions include the installation of temporary fencing at the dripline of each protected tree during the construction period; installation of all utility services and drainage lines and irrigation lines outside of the dripline of each tree. Additionally, except as permitted by a Dripline Encroachment Permit, none of the following activities would occur within the dripline of any Highly Protected Tree: mechanical excavation; construction or installation of any structure, foundation or paving; intentional or incidental soil compaction; application of fill soil 4 inches or greater. Full compliance with Walnut Creek Tree Preservation Ordinance stipulations regarding preservation and maintenance of existing trees would result in a less-than-significant impact to the three Highly Protected Valley Oaks within the Project site. g. Public Art Master Plan The Project would comply with the requirements of the Public Art Master Plan and implementing ordinance by providing art on-site. The Applicant has held a series of meetings with the Arts Council for determination of appropriate art locations and potential forms of artistic impressions to be installed as required. The estimated public art budget for the Project is $1.1 million dollars. 3. Conflict with any applicable habitat conservation plan or natural community conservation plan. The proposed Project site is located in the Core Area of Walnut Creek and both the Project site and the surrounding area are highly developed. There are no habitat conservation plans or natural community conservation plans in force which would apply to the proposed Project, 10 and therefore, there would be no impact with regard to conservation plan conflicts. 10 City of Walnut Creek, 2005, Walnut Creek General Plan 2025 EIR, page

248 LAND USE AND PLANNING E. Cumulative Impacts This section analyzes potential impacts related to land use that could occur from a combination of the proposed Project with other past, present, and reasonably foreseeable projects in the surrounding area. Cumulative projects considered in this analysis are situated within 2 miles of the Project site and are listed in Table 4-1, in Chapter 4, Environmental Evaluation. Cumulative impacts would occur if development associated with the Project together with other cumulative projects listed would physically divide an existing community or conflict with applicable land use plans, policies, or regulations or with an adopted conservation plan. Buildout of the proposed Project would result in 596 new residential units, approximately 22,000 square feet of new commercial space, and 16,700 square feet of new flex space for commercial or residential use over a period of 5 years from 2013 to As described above, the City s Growth Management Program limits the total amount of commercial development in Walnut Creek to 75,000 square feet per year, metered in two-year increments. New development projects must apply for and receive an allocation of total permitted commercial square footage. In recent years, the City of Walnut Creek has not met or exceeded this cap. 11 Additionally, continued implementation of the Growth Management Program would ensure that the cumulative total of commercial development in Walnut Creek does not exceed the standard established in General Plan As discussed above, the proposed Project would not conflict with any applicable land use plans, policies, or regulations, as amended in conjunction with the Project. In addition, the proposed Project would not physically divide an existing community, nor would the proposed Project conflict with an adopted habitat conservation plan. Because the proposed Project would result in less-than-significant impacts to land use in the vicinity of the Project site and 11 Chip Griffin, Associate Planner, Personal Communication with The Planning Center DC&E, February 9,

249 LAND USE AND PLANNING the proposed Project would be consistent with established County and City land use plans and policies, a less-than-significant impact would occur. F. Impacts and Mitigation Measures The Project would not result in any significant project-specific or cumulative impacts related to land use and planning and therefore no mitigation measures are required

250 LAND USE AND PLANNING

251 4.8 NOISE This chapter describes the existing noise and vibration setting on the Project site and in the surrounding area; and analyzes the potential noise and vibration impacts that could result from construction and operation of the Project. Included in this chapter is background information on noise and vibration, a brief summary of the regulatory framework that pertains to the Project, and a presentation of noise monitoring surveys made at the site. A. Regulatory Framework Federal, State, and local regulatory criteria have been developed to minimize noise and vibration exposure at sensitive land uses. This section describes the regulatory framework related to noise and vibration in the vicinity of the Project site. 1. Federal Standards The Federal Transit Administration (FTA) has identified vibration impact criteria for sensitive buildings, such as high-tech manufacturing, residences, and institutional land uses near rail transit and railroads. The vibration impact criteria are in terms of the velocity of the ground expressed on the decibel scale. As employed by the FTA, the reference velocity is 1 x 10-6 in./sec. Root Mean Square (RMS) 1, which equals 0 VdB, and 1 in./sec. equals 120 VdB. The abbreviation VdB is used in this document for vibration decibels to reduce the potential for confusion with sound decibels. The thresholds for residences and buildings where people normally sleep are 72 VdB for frequent events (more than 70 events of the same source per day), 75 VdB for occasional events (30 to 70 vibration events of the same source per day), and 80 VdB for infrequent events (less than 30 vibration events of the same source per day). Table summarizes the FTA s vibration impact criteria for sensitive buildings, residences, and institutional land uses near rail transit and railroads. 1 RMS velocity is defined as the average of the squared amplitude of the signal

252 NOISE TABLE GROUNDBORNE VIBRATION IMPACT CRITERIA Groundborne Vibration Impact Levels (VdB re 1 µinch/sec, RMS) Land Use Category Frequent Events Occasional Events Infrequent Events Category 1 Buildings where vibration would interfere with interior operations. Category 2 Residences and buildings where people normally sleep. 65 VdB 65 VdB 65 VdB 72 VdB 75 VdB 80 VdB Category 3 Institutional land uses with primarily daytime use. 75 VdB 78 VdB 83 VdB Note: An event refers to the passing of a train. Frequent events (more than 70 events of the same source per day), occasional events (30 to 70 vibration events of the same source per day), infrequent events (less than 30 vibration events of the same source per day) Source: U.S. Department of Transportation, Federal Transit Administration, Transit Noise and Vibration Impact Assessment, May 2006, FTA-VA State Standards Multi-family housing in the State of California is subject to the environmental noise limits set forth in the 2010 California Building Code (Chapter 12, Appendix Section ). The noise limit is a maximum interior noise level of 45 dba Ldn (technical terms are defined in Section B). Where exterior noise levels are projected to exceed 60 dba Ldn at the façade of a building, a report must be submitted with the building plans describing the noise control measures that have been incorporated into the design of the Project to meet the noise limit

253 NOISE 3. Local Regulations a. Walnut Creek General Plan 2025 The Safety and Noise Chapter of General Plan 2025 sets forth the policies and actions to assess and control environmental noise. It likewise provides quantitative standards for exterior noise that are identified as normally acceptable, conditionally acceptable, or unacceptable levels, as shown in Figure Goal 8. Provide compatible noise environments for new development, redevelopment, and condominium conversions. Policy 8.1 Policy 8.2 Apply the noise and land use compatibility table and standards to all residential, commercial, and mixed-use proposals, including condominium conversions. Address the issue of residences affected by intermittent urban noise from sources such as heating, ventilating, and airconditioning equipment, and by outdoor maintenance activities such as parking lot sweeping and early morning garbage collection. Action For new multi-family residential projects and for residential component of mixed-use development, use a standard of 65 Ldn in outdoor areas, excluding balconies. Action Strive for a maximum interior noise level of 45 Ldn in all new residential units. Action For new downtown mixed-use development or for new residential development affected by noise from BART or helicopters, ensure that the maximum noise levels do not exceed 50 Lmax in bedrooms and 55 Lmax in other rooms. 2 2 General Plan 2025 contains a typographical error which is corrected here. Action established that maximum noise levels must not exceed 50 Lmax in bedrooms and 55 Lmax in other rooms, not 50 Ldn in bedrooms and 55 Ldn in other rooms

254 NOISE Figure Land Use/Noise Compatibility Source: Walnut Creek General Plan 2025, page Goal 9. Control excessive noise sources in existing development. Policy 9.1 Control all residential and commercial noise sources to protect the existing noise environment

255 NOISE Action Require the evaluation of noise mitigation measures for projects that would cause a substantial increase in noise. Policy 9.2 Strive to reduce traffic noise levels in existing residential areas. Action Action Install quiet pavement surfaces for repaving projects, where feasible. Control vehicle-related noise. b. Walnut Creek Municipal Code Walnut Creek regulates noise in Title 4, Chapter 6, Article 2 of the Municipal Code. The Municipal Code does not establish quantitative noise limits. Municipal Code section (f) addresses construction or repair of buildings and prohibits the following: [t]he erection, construction, demolition, alteration, or repair of any building, structure or residence that requires a permit, or the excavation of any earth, fill, streets, or highways that requires a grading permit, other than between the hours of 7:00 a.m. and 6:00 p.m. on weekdays, which are not holidays, or those precise hours of operation enumerated in individual building and grading permits. B. Sound Terminology There are several noise measurement scales that are used to describe noise in a particular location. A decibel (db) is a unit of measurement that indicates the relative amplitude of a sound. The zero on the decibel scale is based on the lowest sound level that the healthy, unimpaired human ear can detect. Sound levels in decibels are calculated on a logarithmic basis. Each 10-decibel increase in sound level is perceived as approximately a doubling of loudness over a fairly wide range of intensities. There are several methods of characterizing sound. The most common in California is the A-weighted sound level (dba). All sound levels in this report 4.8-5

256 NOISE are A-weighted, unless reported otherwise. This scale gives greater weight to the frequencies of sound to which the human ear is most sensitive. Because sound levels can vary markedly over a short period of time, a method for describing either the average character of the sound or the statistical behavior of the variations must be utilized. Most commonly, environmental sounds are described in terms of an average level that has the same acoustical energy as the summation of all the time-varying events. This energyequivalent sound/noise descriptor is called Leq. An hour is the most common period of time over which average sound is measured, but it can be measured over any duration. Since sensitivity to noise increases during the evening and at night, when excessive noise can interfere with the ability to sleep, 24-hour descriptors have been developed that incorporate artificial noise penalties added to quiet-time noise events. The Day/Night Average Sound Level, Ldn, is a measure of the cumulative noise exposure in a community, with a 10 db addition to nocturnal (10:00 p.m. - 7:00 a.m.) noise levels. Technical terms are defined in Table Representative outdoor and indoor noise levels are shown in Table Effects of Noise The thresholds for speech interference indoors are approximately 45 dba if the noise is steady and approximately 55 dba if the noise is fluctuating. Outdoors the thresholds are roughly 15 dba higher. Steady noise above 35 dba and fluctuating noise levels above roughly 45 dba have been shown to affect sleep. 3 Causes for annoyance include interference with speech, radio and television, house vibrations, and interference with sleep and rest. The Ldn as a measure of noise has been found to provide a valid correlation of noise level and the percentage of people annoyed. The threshold for annoyance from vehicle noise is about 55 dba Ldn. At an Ldn of about 60 dba, approximately 8 3 Karl D. Kryter, The Effects of Noise on Man, Second Edition

257 NOISE TABLE DEFINITIONS OF ACOUSTICAL TERMS Term Decibel, db Definitions A unit describing the amplitude of sound. The number of complete pressure fluctuations per second Frequency, Hz above and below atmospheric pressure. Decibel level as measured using the A-weighting filter network which de-emphasizes the very low and very high frequency components of the sound in a manner similar to the A-Weighted Sound Level, dba frequency response of the human ear and correlates well with subjective reactions to noise. All sound levels in this report are A-weighted, unless reported otherwise. L01, L10, L50, L90 Equivalent Noise Level, Leq Day/Night Noise Level, Ldn Lmax, Lmin Ambient Noise Level Intrusive Source: Illingworth & Rodkin, Inc., The A-weighted noise levels that are exceeded 1%, 10%, 50%, and 90% of the time during the measurement period. The average A-weighted noise level during the measurement period. The average A-weighted noise level during a 24-hour day, obtained after addition of 10 decibels to levels measured in the night between 10:00 pm and 7:00 am. The maximum and minimum A-weighted noise level during the measurement period. The composite of noise from all sources near and far. The normal or existing level of environmental noise at a given location. Noise which intrudes over and above the existing ambient noise at a given location. Relative intrusiveness depends on amplitude, duration, frequency, time of occurrence and tonal or informational content as well as the prevailing ambient noise level. percent of the population is highly annoyed. When the Ldn increases to 70 dba, the percentage of the population highly annoyed increases to about 20 to 25 percent of the population. There is, therefore, an increase of about two percent per decibel of increased noise between an Ldn of 60 to 70 dba

258 NOISE TABLE TYPICAL SOUND LEVELS Outdoor Sound dba Indoor Sound Threshold 140 Civil Defense Siren (100') 130 Jet Takeoff (200') 120 Pain Threshold 110 Diesel Pile Driver (100') Train Horn (100 ) 90 Rock Music Concert Boiler Room Printing Press Plant Very Loud Freight Cars (50') 80 Vacuum Cleaner Freeway (200 ) Expressway (100') Light Aircraft Light Traffic (100') Large Transformer (200') 70 In Kitchen With Garbage Disposal Running 60 Data Processing Center 50 Department Store Moderately Loud Quiet Neighborhood 40 Private Business Office Soft Whisper (5') 30 Quiet Bedroom Quiet 20 Recording Studio 10 Source: Illingworth & Rodkin, Inc., Threshold of Hearing 2. Groundborne Vibration Ground vibration consists of rapidly fluctuating motions or waves with an average motion of zero. Several methods are typically used to quantify the amplitude of vibration including Peak Particle Velocity (PPV) and Root Mean Square (RMS) velocity. PPV is defined as the maximum instantaneous 4.8-8

259 NOISE positive or negative peak of the vibration wave. RMS velocity is defined as the average of the squared amplitude of the signal. PPV and RMS vibration velocity amplitudes are used to evaluate human response to vibration. Table displays human annoyance and the effects on buildings resulting from continuous vibration. As discussed previously, annoyance is a subjective measure and vibrations may be found to be annoying at much lower levels than those shown, depending on the level of activity or the sensitivity of the individual. To sensitive individuals, vibrations approaching the threshold of perception can be annoying. Low-level vibrations frequently cause irritating secondary vibration, such as a slight rattling of windows, doors or stacked dishes. The rattling sound can give rise to exaggerated vibration complaints, even though there is very little risk of actual structural damage. In high noise environments, which are more prevalent where groundborne vibration approaches perceptible levels, this rattling phenomenon may also be produced by loud airborne environmental noise causing induced vibration in exterior doors and windows. Construction activities can cause vibration that varies in intensity depending on several factors. Pile driving and vibratory compaction equipment typically generate the highest construction related groundborne vibration levels. Because of the impulsive nature of such activities, the use of the peak particle velocity descriptor (PPV) has been routinely used to measure and assess groundborne vibration and almost exclusively to assess the potential of vibration to induce structural damage and the degree of annoyance for humans. The two primary concerns with construction-induced vibration, the potential to damage a structure and the potential to interfere with the enjoyment of life, are evaluated against different vibration limits. Studies have shown that the threshold of perception for average persons is in the range of 0.2 to 0.3 mm/sec (0.008 to inches/sec), PPV. Human perception to vibration varies with the individual and is a function of physical setting and the type of 4.8-9

260 NOISE TABLE REACTION OF PEOPLE AND DAMAGE TO BUILDINGS FOR CONTINUOUS/FREQUENT INTERMITTENT VIBRATION LEVELS Velocity Level, PPV (in/sec) Human Reaction Effect on Buildings 0.02 Barely perceptible Vibration unlikely to cause damage of any type to any structure 0.08 Distinctly perceptible Recommended upper level of the vibration to which ruins and ancient monuments should be subjected 0.1 Strongly perceptible Virtually no risk of damage to normal buildings 0.3 Strongly perceptible to severe Threshold at which there is a risk of damage to older residential dwellings such as plastered walls or ceilings Threshold at which there is a risk of damage to newer residential structures Severe - Vibrations 0.5 considered unpleasant Source: Transportation- and Construction-Induced Vibration Guidance Manual, California Department of Transportation, June vibration. Persons exposed to elevated ambient vibration levels such as people in an urban environment may tolerate a higher vibration level. Architectural damage can be classified as cosmetic only, such as minor cracking of building elements, while structural damage may threaten the integrity of a building. Safe vibration limits that can be applied to assess the potential for damaging a structure vary by researcher and there is no general consensus as to what amount of vibration may pose a threat for structural damage to a building. Construction-induced vibration that can be detrimental to the building is very rare and has only been observed in instances where the structure is in a high state of disrepair and the construction activity occurs immediately adjacent to the structure. Railroad and transit operations (i.e. BART) are potential sources of substantial ground vibration depending on distance, the type and the speed of trains, and the type of track. Human response to ground vibration has been corre

261 NOISE lated best with the velocity of the ground. The velocity of the ground is expressed on the decibel scale. The reference velocity is 1 x 10-6 inch/second RMS, which equals 0 VdB, and 1 inch/second equals 120 VdB. The abbreviation VdB is used in this document for vibration decibels to reduce the potential for confusion with sound decibels. One of the problems with developing suitable criteria for groundborne vibration is the limited research into human response to vibration and, more importantly, human annoyance inside buildings. The U.S. Department of Transportation, Federal Transit Administration has developed rational vibration limits that can be used to evaluate human annoyance to groundborne vibration. These criteria are primarily based on experience with rapid transit and commuter rail systems. C. Existing Conditions 1. Noise The Papadimos Group analyzed the existing noise conditions at the Project site in An ambient noise survey was completed by Illingworth & Rodkin, Inc., in 2009, as a part of the peer review of the Papadimos Group report and to confirm the applicability of the baseline measurements. The Project site adjoins I-680 and is transected by the BART line. These two transportation corridors are the most significant sources of noise affecting the Project site and surrounding areas. Vehicular traffic on local major roadways, including Ygnacio Valley Road and North California Boulevard, also contribute to existing noise levels at the site. Noise levels were monitored in 2006 over a period of 24 hours or more at three locations on the Project site and in surrounding areas. Short-term attended measurements were made at six additional locations. The locations of noise measurements are shown in Figure and the results of the noise surveys are summarized in Table and the locations are further defined following the table

262 NOISE Pringle Avenue A Riviera Avenue B North California Boulevard 4 5 Ygnacio Valley Road C NORTH Feet Source: Papademos Group, FIGURE NOISE MEASUREMENT LOCATIONS