9 First American Way - Soils Report

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Lutzky Associates Development, LP - Geotechnical Investlgalion MACTEC Project 4953-03-2631 Sepiember 18,2003 List of Historic Earthquakes Earthquake Distance to Direction to (Oldest to Youngest) Date of Earthquake Magnitude Epicenter Epicenter (Miles) Long Beach March 10,1933 6.4 9 SW Tehachapi July 21,1952 7.5 116 NW San Fernando February 9,1971 6.6 58 NW Whittier Narrows October 1,1987 5.9 28 NW Sierra Madre June 28,1991 5.8 40 N Landers June 28,1992 7.3 87 ENE Big Bear June 28,1992 6.4 67 ENE Northridge January 17, 1994 6.7 53 NW Hector Mine October 16,1999 7.1 132 NE The site could be subjected to strong ground shaking in the event of an earthquake. However, this hazard is common in Southern California and the effects of ground shaking can be mitigated by proper engineering design and construction in conformance with current building codes and engineering practices. Slope Stability The relatively flat-lying topography at the site precludes both stability problems and the potential for lurching (earth movement at right angles to a cliff or steep slope during ground shaking). According to the City of Santa Ana General Plan (1982) and the County of Orange Safety Element (1995), the site is not within an area identified as having a potential for slope instability. Additionally, the site is not located within an area identified as having a potential for seismic slope instability (California Division of Mines and Geology, 1998). There are no known landslides near the site, nor is the site in the path of any known or potential landslides. Liquefaction and Seismic-Induced Settlement Liquefaction potential is greatest where the ground water level is shallow, and submerged loose, fine sands occur within a depth of about 15 meters (50 feet) or less. Liquefaction potential decreases as grain size and clay and gravel content increase. As ground acceleration and shaking duration increase during an earthquake, liquefaction potential increases. 12