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EXHIBIT A
<br />structures to potential substantial adverse effects from rupture of a known earthquake fault that is
<br />delineated on an Alquist-Priolo Earthquake Fault Zoning Map or any other known fault. (Initial Study,
<br />pp. 29-30)
<br />9.6.1.2 Exposure to Potential Risk of Loss, Injury, or Death — Seismic Ground Shaking
<br />Threshold: Would the Project expose people or structures to potential substantial adverse effects,
<br />including the risk of loss, injury or death involving strong seismic ground shaking?
<br />Finding: Less than significant impact. (DEIR, p. 2-6; Initial Study, p. 30)
<br />Facts in Support of Finding: The Project site is located within the seismically active region of Southern
<br />California. The principal seismic hazard that could affect the site is ground shaking resulting from an
<br />earthquake occurring along several major active or potentially active faults in Southern California. As
<br />discussed above, the closest active faults are the Elsinore Fault and the Newport -Inglewood -Rose Canyon
<br />Fault Zone that are both located approximately 10 miles from the Project site. Movement along these
<br />faults, or other regional faults, could result in seismic ground shaking on the Project site.
<br />However, structures built in the City are required to be built in compliance with the California Building
<br />Code (CBC [California Code of Regulations, Title 24, Part 2]), as included in the City's Municipal Code
<br />as Chapter 8, Article 2, Division 1, which regulates all building and construction Projects within the City
<br />and implements a minimum standard for building design and construction that includes specific
<br />requirements for seismic safety, excavation, foundations, retaining walls and site demolition. Because the
<br />Project must be constructed in compliance with the CBC and the City's Municipal Code, which would be
<br />verified through the City's plan check and permitting process, the proposed Project would result in a less
<br />than significant impact related to strong seismic ground shaking.
<br />9.6.1.3 Exposure to Potential Risk of Loss, Injury, or Death — Seismic -Related Ground
<br />Failure, Including Liquefaction
<br />Threshold: Would the Project expose people or structures to potential substantial adverse effects,
<br />including the risk of loss, injury or death involving seismic -related ground failure, including liquefaction?
<br />Finding: Less than significant impact. (DEIR, p. 2-6; Initial Study, pp. 30-31)
<br />Facts in Support of Finding: Soil liquefaction is a phenomenon in which saturated, cohesionless soil
<br />layers, located within approximately 50 feet of the ground surface, lose strength due to cyclic pore water
<br />pressure generation from seismic shaking or other large cyclic loading. During the loss of stress, the soil
<br />acquires "mobility" sufficient to permit both horizontal and vertical movements. Soil properties and soil
<br />conditions such as type, age, texture, color, and consistency, along with historical depths to ground water
<br />are used to identify, characterize, and correlate liquefaction susceptible soils. Soils that are most
<br />susceptible to liquefaction are clean, loose, saturated, and uniformly graded fine-grained sands that lie
<br />below the groundwater table within approximately 50 feet below ground surface. Lateral spreading is a
<br />form of seismic ground failure due to liquefaction in a subsurface layer. The California Geological Survey
<br />Seismic Hazard Zones Orange Quadrangle map shows the Project site is within a liquefaction zone.
<br />However, exploratory borings at the Project site identified groundwater at approximately 110 feet below
<br />the ground surface, and borings on the Project site did not encounter groundwater to the maximum depth
<br />of 85 feet that was explored. Likewise, the groundwater wells that are located near the Project site identify
<br />Resolution No. _
<br />Certification of the Magnolia at the Park EIR
<br />75E-65
<br />Page 27 of 71
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