31B - CUP - 1901 NORTH FAIRVIEW ST

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City of Santa Ana Environmental Checklist All new construction in the State of California must comply with the seismic design parameters contained in the 2010 California Building Code (CBC) seismic requirements. Compliance with the CBC standards in the design and construction of the proposed project would reduce impacts related to ground shaking. Additionally, as required in Mitigation Measure GEO -1, the proposed project would comply with all geotechnical recommendations provided in the Geotechnical Exploration Report (Appendix B) to minimize seismic damage and reduce seismic ground shaking impacts. Therefore, potential impacts related to strong seismic ground shaking are less than significant with implementation of Mitigation Measure GEO -1. Mitigation Measure GEO -1: Prior to the issuance of grading or building permits, the City of Santa Ana Planning and Building Agency will ensure that all design criteria and specifications set forth in the Geotechnical Exploration Report will be implemented as a condition of project approval and shown on the appropriate engineering plans and documents. At a minimum the recommendations will include the following: Providing a design capable of withstanding seismic hazards related to strong ground motions. • Earthwork procedures to address soils and subsurface conditions, including liquefaction. • Recommendations for foundations, soils preparations, and slabs design to resist the effects of lateral pressures. a3. Seismic - related ground failure, including liquefaction? Less - than - Significant Impact with Mitigation Incorporated. Soil liquefaction is a phenomenon in which saturated, cohesionless soils layers, located within approximately 50 feet of the ground surface, lose strength due to cyclic pore water pressure generation from seismic shaking or other large cyclic loading. During the loss of stress, the soil acquires "mobility" sufficient to permit both horizontal and vertical movements. Soils that are most susceptible to liquefaction are clean, loose, saturated, and uniformly graded fine- grained sands that lie below the groundwater table within approximately 50 feet below ground surface. The Geotechnical Exploration Report identified liquefaction as a potential geological condition of the project site (Appendix B). Also, according to both Exhibit 5 of the Seismic Safety Element of the City's General Plan and the California Department of Conservation Division of Mines and Geology (CDMG) Seismic Hazards Zone Map for the Anaheim Quadrangle (California Department of Conservation, Division of Mines and Geology 1998), the project site is located within a liquefaction area where historic occurrence of liquefaction or local geological, geotechnical, and groundwater conditions indicate a potential for permanent ground displacements. Historical high groundwater elevations below the project site are as shallow as 15 feet bgs. For preparation of the Geotechnical Exploration Report, nine borings were taken at the project site to measure for depths to groundwater. Groundwater was encountered in all borings at depths below 32 feet bgs. The depth to groundwater ranges between 32.0 and 41.6 feet. Soils at the project site consist of undocumented artificial fill which blankets most the site at depths ranging from 3 -5 feet bgs and Quaternary age fluvial soils which consist predominately of sands of the Santa Ana River drainage. The pre - dominant near - surface material is brown to light yellow brown, thinly bedded to massive, loose to medium dense, dry to moist, fine to coarse sand with varying proportions of silt with sub - rounded to well - rounded gravel. Locally soft to stiff, thinly bedded to laminated, brown to olive brown, moist to wet sandy clayey silts to fat lean clays were also encountered on the project site (Appendix B). The Academy Charter high School 3-38 June 2012 Initial Study /Mitigated Negative Declaration ICF 00914.11 31 B -114