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7.A. - Page 26 settlement, and slope instability). The geotechnical report is subject to City Building Official approval prior to the issuance of grading and building permits. (DTPP EIR p. 16-4) The required contents of the geotechnical report are described in DTPP 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. iii) Liquefaction is a process whereby strong ground shaking causes loose, saturated, unconsolidated sediments to lose strength and behave as a fluid. The site-specific geotechnical report required for the project (see item ii above) will also address liquefaction potential. iv) The project site is relatively flat; therefore, no impacts from landslides are anticipated. In conclusion, the Downtown Precise Plan EIR concluded that while the DTPP area could be subject to moderate to high susceptibility to ground shaking and liquefaction, the City's routine grading and building permit regulations provide reasonable assurances that the project will incorporate the design and engineering refinements necessary to reduce the impact of DTPP facilitated development to a less-than-significant level, requiring no additional mitigation. b. The project shall be subject to Downtown Precise Plan EIR Mitigation 16-3, which shall be required as a condition of project approval. The mitigation requires the applicant to prepare an erosion control plan subject to City approval and consistent with the required San Mateo County Stormwater Pollution Prevention Plan (SWPPP) Best Management Practices. The plan shall be implemented during construction and will reduce the potentially significant impact on soil erosion and sedimentation to a less-than-significant level. The proposed amendments would not alter requirement for new development to comply with the DTPP EIR mitigation measures; therefore, no new impacts are anticipated. c. No changes to geologic substructures are expected to occur as a result of project implementation or the amendments to the DTPP. As described in item (a) above, the proposed project will comply with all local and State codes and regulations, and project design will incorporate City-approved geotechnical recommendations for site development. Therefore, this impact is considered less than significant. Project plans (Sheets CI.O and Ll.l, 4/26/13) indicate proposed areas of cut and fill near the intersection of Middlefield and,Iefferson to reduce the grade and to facilitate pedestrian movement at the intersection. d. The Downtown Precise Plan EIR (p. 16-6) determined that development within the DTPP area may be subjected to hazards from expansive soils, representing a potentially significant impact. Mitigation 16-1 requires that the geotechnical report required by the City Building Official include an analysis of expansive soil hazards and recommended stabilization measures. Implementation of these measures, combined with conformance with standard California Building Code and other applicable State and local regulations (all of which will be required as conditions of approval for the project) will reduce the potential effect of expansive soils to a less-than-significant level. In addition, the DTPP EIR (p. 16-8) also noted that development occurring under the DTPP would be subject to damage due to the presence of corrosive soils within the DTPP area. Mitigation 16-2 specifies that burzed metal infrastructure have cathodic protecting using a sacrificial anode system that conforms to Part VII (G) of the City's water system design criteria and standard specification details Section 02661. Additionally, concrete mixes must conform to Caltrans specifications for Protection of Reinforcement Against Corrosion Due to Chlorides, Acids, and Sulfates as outlined in Memo to Designers 10-5, January 2002. These measures, which shall be required as conditions of approval for the project, will reduce the potential impacts of corrosive soils on the project to a less- than-significant level. e. There would be no use of septic tanks or alternative wastewater disposal systems for the project. No impact will occur. 17