31B - CUP - 1901 NORTH FAIRVIEW ST

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City of Santa Ana Discussion Would the project: Environmental Checklist a. Expose people or structures to potential substantial adverse effects, including the risk of loss, injilay, or death involving. a1. Rupture ofa known earthquake fault, as delineated on the most recent Alquist - Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area or based on other- substantial evidence ofa known farrlt?RefertoDivision of Mines and Geology Special Publication 42, Less - than - Significant Impact The Alquist - Priolo Act requires the California State Geologist to identify areas in the state that are at risk from surface fault rupture. These areas are known as Earthquake Fault Zones. As described in the Geotechnical Exploration Report prepared for the proposed project (Appendix B), the project site is not located within a mapped Alquist- Priolo Earthquake Fault Zone, and there are no known surface traces of any active, potentially active, or inactive faults crossing through or extending toward the project site. The nearest fault zone is the Newport Inglewood, which is associated with potentially active faults in the vicinity of Newport Beach and the Los Angeles Basin and is located approximately 8.6 miles to the southwest of the proposed project site (Appendix B). As a result, the potential for a surface rupture to occur at the project site is low. Therefore, potential impacts related to rapture of a known earthquake fault are less than significant. a2. Strong seismic ground shaking? Less - than - Significant Impact with Mitigation Incorporated. As discussed in Vl.al, the proposed project is not located within or adjacent to a fault zone. However, because the proposed project is located within a seismically active region, in fairly close proximity to several major active faults, the project site is likely to experience strong ground shaking during the lifespan of the proposed project. The Newport - Inglewood Fault Zone (8.6 miles distant) is of most concern to the project site. In addition, the San Andreas (43 miles distant) and Raymond Faults (30 miles distant) are also proximate and could affect Santa Ana (City of Santa Ana 1982). Earthquake intensities experienced at the project site would vary depending upon the earthquake's magnitudes, distance between the project site and the fault, and the types of materials underlying the project site. According to the Land Use Element of the City's General plan, the greatest potential for earthquake damage is expected to come frorn a large earthquake along the Newport - Inglewood fault. A magnitude 7 earthquake along this fault would be expected to cause significant damage regionally. In preparation of the Geotechnical Exploration Report, a site- specific evaluation of the peak ground accelerations associated with the event having a 2% probability of being exceeded in 50 years and the maximum magnitude event on the fault system. Based on the site - specific ground motion evaluation, the results of the analyses suggest that the site specific design Peak Horizontal Ground Acceleration (PHGA) is approximately 0.38g based on the site - specific Maximum Considered Earthquake (MCE) PHGA of 0.57g. The ground motions were determined using the site - specific criteria per the 2010 CBC. In addition to this information, the Geotechnical Exploration Report provides recommendations that have been developed based on the engineering properties of the onsite soils and their anticipated behavior during and after construction. The Academy Charter High School 12 3 37 tune 20 Initial Study /Mitigated Negative Declaration ICF 0092011 31 B -113