ARCHIVED REPORTS LEC APPLICATION FOR CERTIFICATION

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San Andreas, and Greenville Faults. The California Department of Conservation Division of Mines and Geology (CDMG) Open File Report 92-1 reports that the Calaveras, Hayward, San Andreas, and Greenville, have a strike-slip style of faulting. Approximate distances, and anticipated earthquake magnitudes, associated with the Maximum Credible Earthquake are presented below (Jennings, 1994; Mualchin and Jones 1992): Approximate Distance Maximum Credible Fault Name From Site(mi) Earthquake Magnitude Calaveras 39 7.25 Hayward 48 7.25 San Andreas 69 8 Greenville 30 7.25 Seismic design should be performed in accordance to the 2007 California Building Code (ICBO, 2007). The project structural engineer should assess the need for seismic response spectra for design of the project as required by applicable codes. 4.6 SEISMIC HAZARDS 4.6.1 Liquefaction Seismic liquefaction occurs when excess pore pressures are generated in loose, saturated, generally cohesionless soil during earthquake shaking, causing the soil to experience a partial to complete loss of shear strength. Such a reduction/loss of shear strength can result in both settlement and horizontal movement (lateral spreading) of the soil mass. Analysis of the liquefaction potential for sediments beneath the site follows procedures outlined by Idriss and Boulanger. Based on the relatively loose sandy soil and shallow groundwater conditions, our analyses indicate the potential for liquefaction to occur in the areas explored is considered to be moderate. Liquefiable zones are anticipated to be restricted to isolated pockets of loose,near-surface,sandy soils. Geotechnical investigations,which will be completed to support project design and construction,should evaluate areas that may be subject to seismically induced settlement. Standard design and construction techniques can then be used to mitigate the potential for damage due to seismically induced settlement. It is anticipated over-excavation of approximately 5 feet and recompaction as engineered fill will reduce the risk of damage to structures from differential settlement associated with liquefaction to tolerable levels. Recommendation for the extent of over-excavation and compaction characteristics of the engineered fill should be provided in the design-level geotechnical report. 4.6.2 Seismic Settlement Seismic settlement generally occurs when relatively loose to medium dense cohesionless soils come to a more compact or dense state under earthquake shaking. The settlement can occur as a result of liquefaction or in dry soils. Due to the relatively dense state and material properties of the soil at the site, we judge that significant seismic settlement is unlikely to occur in the areas explored. 4.6.3 Ground Surface Rupture The site is not mapped in an "Earthquake Fault Zone" (CGS, 1997). Based upon this information, the probability of ground surface rupture along a fault trace is considered to be low at the site. IMProject No.5593-01-05 C A R LT O I,i 7/29/2008 g Engineering Inc . NCPA GFS.doc