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6.1 E Page 8 PhOPUSI>ll WURK PROCkA1i, SC'1iF.Dl:Lii AND 6[IDCE:T FOR TpF, pR£$EIiYf: Ai R6DN'OOU 5190RES MARCH 2OU7 a Ma�mitude 7.9 cvent on the San Andreas I'ault{similar to the 1906 earthquake)would result in violent(MMI-IX) shaking at the site. A sibmif cant seismic event on one of the sevcral active faults (San Andreas, F-Iayward-Rod�ers Cree1�, Concord,and Calaveras)within the region(which would almost ecrtainly occur at some time over the lifetune of the project) may result in direct{e.g., shak.ing-related damage to buildings and other improvements) and/or indirect impacts(e.g., earthquake-induced settletnents or liquefaction) to the completed project. :E3ased on ABA the project site is subject to a moderate to high hazard for Iiquefaction. b. Approach.Baseline would prepare fhe Geology, 5oils and Seismicity subsection. The analysis would describe the existing regional and site-specific geologic setting,evaluate potential i�npacts iu comparisoii to Redwood City's CEQA significance criteria,and draft practicat mitigation meas�.ires to mitigate identified significant impacts,where appropriate. In preparation of the Geology and Soils subsecnon of the E1R for the proposed project,the following tasks would be completed: • Peer review afgeotecknical report. Peer review and evaluate the Treadweil and Rollo geotech- nicat reasibility study for completeness. • Describe gL�ologic conditiuns. Describe the regional and site-specific geologic and seismic conditions for the projects,based on r.eview of available geotechnical reports and other technical reports for the project sites. • Identify sources uf regio�zal earthquakes. Identify potential sources of regional earthquakes and describe expected levels of seisrnic shaking(and related potential for ground failure) at the project site. • Describe potential seisnzic impact,s.I7escribe potential seismic impacts related to the proposed projects, incluc3ing fault rupture, seismic shaking and earthquake-induced liquefaction. • Contluct a site reco�uzaissance. Conduct a reconnaissance to verify geologic and soil.s conditions and visually inspect conditions at the project site. • Describe soi!cofiditzons. Describe soii condifions(inclnding erosion hazards and shrink-swell potential)at the project site on the basis of Natural Resozzrce Conservation Service mapping and available geotechnica] investigation for the project site. • Describe lor,�al policie�s. Describe existing local policies from the Safety Element of the Redwood City General Plan that address soils and geology. Based on our understanding of the project area, anticipated impacts relating to geology, soils, and seismicity may incl.ude seismic shaking,erosion,differential compaction, and landslide.The following tasl<s would be completed as part of the impacts analysis: • Describe seismic impaccts. Potential seismic impacts,including ground rupture and seismic shaking,would be described. The maxi�num expected earthquake on nearby active faults would likely cause very strong to violent seismic sllaking at the project site. • Descrihe geoteclanical impact.s. Evaluate the details of the proposed project for comptiance with local ordinances and requirements and standard geotechnical principles, including the Field Act for Publie Schools,which mandates building practices to enhance structural safety of public schools. Any potential iznpacts associated with soi] instability would be described. Practical mitigation measures would be drafted that would reduce or eliminate any identitied potential impacts related to geologic, soils, or expected seismic conditions. (:1Da.emontx+�d Jniu�gS�aPaxxmai�3ncnl SnimgslTCO�pursry In�m1e�Piies50LK il',Revittd Scope nnd Nnugei es Canrnn Auuclunmi.doc 5