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City of Pleasanton—Hidden Canyon Residences and Preserve Draft EIR Geology, Soils, and Seismicity FirstCarbon Solutions 3.6-27 https://adecinnovations.sharepoint.com/sites/PublicationsSite/Shared Documents/Publications/Client (PN-JN)/2148/21480016/EIR/3 - Draft EIR/21480016 Sec03-06 Geology.docx to the direct or indirect loss, injury, or death involving landslides induced from strong seismic shaking. The implementation of Mitigation Measure (MM) GEO-1 would require a design-level geotechnical investigation and the review of the proposed project ’s detailed structural, civil, and landscaping plans by a qualified Geotechnical Engineer prior to the issuance of any grading or building permits to ensure required recommendations are incorporated into the design. The qualified Geotechnical Engineer would provide additional findings on any seismic or subsurface hazards that could directly or indirectly result in the destruction to property or risk the injury or death of individuals residing on the project site, including landslide hazards, and shall provide comments and recommendations on any design measures that would be required to be incorporated into the proposed project to reduce impacts related to landslides. Implementation of MM GEO-1 would require City verification of the incorporation of recommended design features by the qualified Geotechnical Engineer prior to the issuance of any building or grading permits. With MM GEO-1, the proposed project would not directly or indirectly generate the risk of loss, injury, or death involving seismically induced landslides. Level of Significance Before Mitigation Potentially significant impact. Mitigation Measures MM GEO-1 Design-level Geotechnical Study Prior to the issuance of any building or grading permits, a design-level geotechnical investigation on the project site and review of detailed site plans shall be performed by a qualified Geotechnical Engineer. The design-level geotechnical investigation could incorporate a variety of field methods and would include (but not be limited to) the following items: • Evaluating the lateral extent and depth of colluvial soils. • Performing a seismic refraction survey to determine shear wave velocities at deeper depths. • Analyzing and developing slope grading and engineered buttress fill design criteria. • Evaluating upslope sources of water. • Evaluating the Site Classification for Seismic Design. • Estimating appropriate minimum building setbacks from the face of fill slopes. The qualified Geotechnical Engineer would be required to demonstrate that implementation of the recommendations would reduce potential impacts associated with liquefaction and landslide potential to below a level of significance in conformance with the standards in the California Building Standards Code (CBC). The applicant would be required to incorporate all recommended design features into project building plans, for review and approval by the City Engineer prior to the issuance of any building or grading permits.