AgdaPkt 2014-10-06 Closed and Joint with SA

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7.3.B. - Page 63 Summary of Impacts Potentially Less than Significant Less than Significant With Mitigation Significant No Impact Incorporated Impact Impact c) Be located on a geologic unit or soil that is unstable, or that would become X unstable as a result of the project, and potentially result in on- or off -site landslide, lateral spreading, subsidence, liquefaction, or collapse? d) Be located on expansive soil, as defined in Table 18 -1 -B of the Uniform X Building Code, creating substantial risks to life or property? e) Have soils incapable of adequately supporting the use of septic tanks or X alternative wastewater disposal systems where sewers are not available for the disposal of wastewater? Documentation: a. z) The Downtown Precise Plan project area is located within the seismically active San Francisco Bay Area. The significant earthquakes that occur in the Bav Area are generally associated with crustal movement along well - defined, active fault zones of the San Andreas Fault system, which trends in a northwesterly direction. The project site is located approximately five miles northeast of the San Andreas Fault. Two other major active faults in the area are the Hayward Fault, located about 14 miles northeast of the project site, and the San Gregorio -Seal Cove Fault, located about 13 miles to the west. (DTPP program EIR p. 16 -1) The project site is not within an Alquist - Priolo Earthquake Fault Zone (DTPP program EIR p. 16 -1); therefore, there is no known potential for fault rupture on the site. it) The project site lies in a seismically active region and is subject to ground shaking from an earthquake along major active regional faults. This is common to virtually all development in the San Francisco Bay Area. Development on the site will be subject to review and approval by the City and shall be designed and constructed in accordance with all applicable seismic standards adopted by the City of Redwood City, including the California Building Code (CBC), which requires that a site - specific geotechnical investigation be conducted and report prepared by a licensed professional. The site - specific geotechnical report must provide measures to reduce potentially significant geologic hazards (e.g., expansive and corrosive soils, differential settlement, and slope instability). The geotechnical report is subject to City Building Official approval prior to the issuance of grading and building permits. (DTPP program EIR p. 16 -4) The required contents of the geotechnical report are described in DTPP program EIR Mitigation 16 -1 and on EIR page 16 -6. Techniques and standards for effective geotechnical practices are widely known and accepted. Individual measures for particular sites and projects are typically specified at a detailed level of design. The City routinely requires such geotechnical /geologic investigations and specifications, and a significant record exists demonstrating the effectiveness of such design and engineering requirements in adequately addressing potential soil and geologic issues. Under the City's grading permit and building permit regulations, an individual development project cannot be given final approval without project compliance with geotechnical.'geologic requirements. These requirements and related City inspection and verification procedures before project occupancy provide reasonable assurances that the project will incorporate the design and engineering refinements necessary. A site - specific preliminary geotechnical report for the proposed project was prepared (Preliminary Geotechnical Evaluation; Treadwell & Rollo; December 12, 2013). The report provides preliminary conclusions and recommendations regarding the following geotechnical issues to be considered during project planning and design: • soil and groundwater conditions • site seismicity and seismic hazards (specifically liquefaction) • probable foundation types • probable temporary shoring types for the partial basement (lower garage level) • settlement behavior • floor slab report • 2013 California Building Code (CBC) seismic design criteria • construction considerations 14