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<br />1 <br />C <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br />Geologist for the area or based on other substantial evidence of a known <br />fault? Refer to Division of Mines and Geology Special Publication 42. <br />Less than Significant Impact. A Geotechnical Investigation Report (Don <br />Solis Engineering, 2006) was prepared for the proposed project.. <br />According to the most recent Alquist-Priolo Zoning Map, no known fault <br />traces are located in the City of Santa Ana. Nonetheless, the project site is <br />located in seismically active Southern California with numerous geologic <br />faults within 50 miles of the City's borders. The most significant faults <br />that may affect the City of Santa Ana are the offshore branch of the <br />Newport-Inglewood system, located approximately nine miles to the <br />southwest, and the Whittier-Elsinore system, located approximately ten <br />miles to the north. Additionally, though further from the City, the San <br />Andreas and Raymond faults could produce large earthquakes. Of all these <br />faults, the Newport-Inglewood system is the one most likely to produce <br />large earthquakes within the next 20 years. The proposed project would <br />not affect subsurface geology or the probability of a seismic event; <br />however, if an earthquake were to occur, the building could sustain <br />damage. Adhering to standard engineering practices and design criteria as <br />contained in the current Uniform Building Code (UBC) relative to seismic <br />and geological hazards, and implementations of recommendations from <br />the Geotechnical Investigation Report, the impacts would be reduced to <br />less than significant levels. <br />A2. Strong seismic ground shaking? <br />Less than Significant Impact. The seismic hazard from ground shaking <br />is typical for the vast majority of areas in Southern California. The <br />greatest potential for a large earthquake comes from the Newport- <br />Inglewood fault, with experts predicting a large damaging earthquake on <br />this fault within the next 20 years. A 7.0 magnitude earthquake on this <br />fault is expected to cause significant and widespread regional damage. <br />However, the implementation of seismic design provisions for structural <br />protection will help minimize threats to life-safety in the event of an <br />earthquake. All structures will be designed in accordance with the seismic <br />design provisions of the UBC to promote maximum safety in the event of <br />an earthquake. Conformance with these standard design parameters would <br />reduce any potential impacts associated with ground shaking to less than <br />significant levels. <br />A3. Seismic related ground failure, including liquefaction? <br />Less than Significant Impact. Liquefaction occurs with the sudden loss <br />of soil strength due to the rapid increase in pore pressure within <br />cohesionless soils as a result of repeated cyclic loading during seismic <br />events. Several conditions must be present for liquefaction to occur <br />including the presence of relatively shallow ground water, generally loose <br />soil conditions, the susceptibility of soils to liquefaction based on grain- <br />size characteristics and the generation of significant and repeated <br />44 <br />Initial Study/Mitigated Negative Declazation <br />Harbor Medical and Retail Center ~ ~ w ~~ <br />July 2008 <br />