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09/09/2013 Impact: Impact 15-1: Geotechnical Hazards Associated with Project Excavation and Grading. The project's proposed excavation and grading activities have the potential to destabilize existing buried utilities and building foundations, or to create conditions that would potentially compromise the safety or stability of proposed project improvements. The project applicant's preliminary geotechnical investigations (Lowney Reports I and II; and Cornerstone Earth Group, March 2008) made initial assessments of these conditions, but a design-level geotechnical investigation will be needed to adequately address all grading and excavation activities on the development site. Without such a study--and without the associated supervision of an engineering geologist or geotechnical engineer during project grading and construction--the safety and long-term stability of existing and proposed project improvements cannot be assured. Mitigation: Mitigation 15-1. As recommended by the project's preliminary geotechnical investigations, prior to City issuance of grading permits for individual project construction phases, the applicant shall be required to retain a registered engineering geologist or geotechnical engineer to prepare detailed, design-level geotechnical investigations to guide the design of all project grading and excavation activities. The detailed, design-level geotechnical investigations shall be performed for each of the structures proposed for the development site. Subsurface conditions shall be explored and laboratory tests conducted on selected soil samples to establish strength parameters for the design of excavations, retained slopes and fill placement, and to determine the corrosive potential of both Bay mud and imported fill on foundation elements and buried utilities. Recommendations from the investigations shall be incorporated into all plans for project grading, excavation, soil support (both temporary and long-term) and utility construction, to the satisfaction of the City Engineer. The detailed, design-level investigations, relevant recommendations, and all associated project grading, excavation and foundation plans, shall be subject to review and approval by an independent engineering geologist or geotechnical engineer retained by the City Engineer at applicant expense. In addition, the project civil engineer shall certify to the City Engineer (e.g., through plan submittal for City review) that all relevant provisions of the investigations have been incorporated into the grading, excavation and construction plans, and all earthwork and site preparation shall be performed under the direct supervision of a registered engineering geologist or geotechnical engineer. Finding: Implementation of Mitigation 15-1 would reduce the potential excavation and grading impacts to a less-than-significant level. Facts in Support of Finding: Implementation of Mitigation 15-1 would reduce potential excavation and grading impacts to a less-than-significant level by requiring detailed, site-specific geotechnical investigations and solutions prepared by a registered engineering geologist or geotechnical engineer, with review and approval authority by the City Engineer. These facts are described in Draft EIR chapter 15 (Geology and Soils) on pages 15-1 through 15-15, which is hereby incorporated by reference. ATTY/RES0.2901/STANFORD EIR CERTIFICATION RESO.#15294 REV:09-10-13 VR MUFF#100 Page 17 of 55