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WORKPLAN Zone 7,Legacy Partners,and/or Kiewit. This scope assumes that the reports that have been prepared for Legacy and Kiewitt will be sufficient such that no additional information is required to evaluate the feasibili:y of different types of development across the site. If required,a separate scope and fee will be prepared to develop additional information required for the planning process. The previous surface mining and excavation activities have resulted in challenging soils characteristics across the site. The geology and soils section of the E.IR will include mapping to depict areas of unstable soils and other hazards that will inform the planning process. The section will include recommendations for construction and project design solutions to compensate for known site conditions. According to the Pleasanton General Plan the site is not located in an Alquist Priolo earthquake fault zone and is not located in a liquefaction zone. However,the Plan Area is identified as being subject to levels of groundshaking that will be sever to violent. Key issues to be evaluated in the FIR include soil stability characi--eristics,the seismicity of the local area,the presence of any nearby existing fault lines and their potential effect on site development,the erodibility of soils,and the expansive characteristics of site soil. Existing published information (soil reports and maps,additional geotechnical reports,other data) will be used. No additional soils or other field geological analyses will be conducted. Mitigation measures will be developed,as appropriate. Hazardous Materials:The Specific Plan area has been mined extensively and other activities in the Specific Plan area include the Pleasanton Garbage Service and asphalt batch plant. The former Kaiser/Hansen quarry site is included by the State on its list of hazardous waste and substances sites, commonly known as the"Cortese list."The potential hazardous wastes listed for the quarry site include hydrocarbons,motor oil,diesel,and fuel oil and additives. Soil and groundwater investigations have been conducted in recent years by the owners of land within the Specific Plan area to determine the nature and extent of hazardous wastes present. As a result of this and follow-up corrective actions by the quarry operators,most of the FPSP area has been determined by the County to require no further action.MBA will review the previous documentation and will identify areas where additional study may be required.The FIR will include mitigation to ensure that future development performs site-specific analysis and remediation commensurate with the intended future use. Hydrology and Water Quality: The Plan area includes a complex chain of Lakes partially within the jurisdiction of Zone 7 Water Agency.The Chain of Lakes provides flood protection through the detention of storm flows and metered releases to Arroyo Mocho and Arroyo Las Positas. The quality of surface water and groundwater is affected by past,current,and ultimately proposed land uses within the Plan Area watersheds as well as by the composition of geologic materials in the vicinity. The Zone 7 Storm Management Master Plan identifies regional capital improvements that remove the Plan Area from the FE MA 100-year flood - ...--., .-._...--- - _ __ _ - _ --._...._...___ _ _ GATES sASSOCIATES