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SAN LEANDRO SHORELINE DEVELOPMENT DRAFT EIR <br />CITY OF SAN LEANDRO <br />GEOLOGY, SOILS, AND SEISMICITY <br />amplification. This is considered a significant impact. Impacts and related mitigations for potential <br />liquefactions hazards are addressed in Impact GEO-3. <br />The Project site is flat; there is no potential for landslide impacts. <br />Impact GEO-1: The Project could expose people or structures to potential substantial adverse effects, <br />including the risk of loss, injury, or death involving strong seismic ground shaking, seismic -related ground <br />failure, including liquefaction and lateral spreading. <br />Mitigation Measure GEO-1: Require geotechnical reports for all development within the Project site, as <br />required by the San Leandro Municipal Code Section 7-12. The geotechnical reports shall consider the <br />potential earthquake related impacts of strong ground shaking amplification due to the soft <br />underlying sediments, as identified in this DEIR. Seismic ground motion parameters shall be provided <br />in the geotechnical reports in accordance with CBC requirements. The building plans shall incorporate <br />all design and construction criteria specified in the report(s). The geotechnical engineer shall sign the <br />improvement plans and approve them as conforming to their recommendations prior to issuance of <br />building permits. The geotechnical engineer shall also assume responsibility for inspection of the work <br />and shall certify to the City, prior to acceptance of the work that the work performed is adequate and <br />complies with its recommendations. The geotechnical engineer of record shall prepare letters and as - <br />built documents to document their observances during construction and to document that the work <br />performed is in accordance with the project plans and specifications. As required by the City of San <br />Leandro, all construction activities shall meet the CBC regulations for seismic safety (i.e. reinforcing <br />perimeter and/or load bearing walls, bracing parapets, etc.). t4 In addition, all project -related grading, <br />trenching, backfilling and compaction operations shall be conducted in accordance with the City of <br />San Leandro Engineering Department's Standard Plans. All improvements shall conform to regulations <br />for seismic safety contained in the CBC. <br />Significance After Mitigation: Less than significant. <br />GEO-2 The Project could result in substantial soil erosion or the loss of topsoil. <br />Soil Erosion or Loss of Topsoil <br />Proper drainage and control of runoff is important in controlling erosion and flooding both during and <br />after construction. Surface drainage ditches and storm drains must be regularly maintained to continue <br />functioning as designed. In addition, proper drainage and erosion control during grading is necessary to <br />14 Seismic design provisions of the CBC generally prescribe minimum lateral forces, applied statistically to the structure and <br />combined with the gravity forces of dead and live loads. The CBC -prescribed lateral forces generally are substantially smaller than <br />the expected peak forces that would be associated with a major earthquake. Therefore, when built according to CBC standards, <br />structures are anticipated to (1) resist minor earthquakes without damage; (2) resist moderate earthquakes without structural <br />damage but with some nonstructural damage; and (3) resist major earthquakes without collapse but with some structural as well <br />as nonstructural damage. Conformance to the current building code standards does not guarantee that significant structural <br />damage will not occur in the event of a maximum magnitude earthquake; but it is reasonable to expect that a well-designed and <br />well -constructed structure would not collapse or cause loss of life in a major earthquake. <br />PLACEWORKS 4.5-11 <br />