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ENGEO <br /> INCORPORATED <br /> <br /> <br />5150.100.101 <br />May 2, 2008 Page 9 <br />5.4.3 2007 CBC Seismic Design Parameters <br /> <br />Using the USGS website Seismic Design Values for Buildings, Ground Motion Parameter <br />Calculator, we provide the 2007 CBC seismic parameters using the ASCE 7.5 and 2006 IBC <br />calculation modules. <br /> <br />TABLE 1 <br />2007 CBC Seismic Parameters <br />Coefficient Value <br />Mapped MCE Spectral Response Acceleration at Short Periods, SS 1.985 <br />Mapped MCE Spectral Response Acceleration at a Period of 1 second, S1 0.745 <br />Site Class C <br />Long-period Transition Period, TL 8 sec <br />MCE, 5% Damped, Spectral Response Acceleration at Short Periods <br />Adjusted for Site Class Effects, SMS 1.985 <br />MCE, 5% Damped, Spectral Response Acceleration at a Period of 1 second <br />Adjusted for Site Class Effects, SM1 0.969 <br />Design, 5% Damped, Spectral Response Acceleration at Short Periods, SDS 1.324 <br />Design, 5% Damped, Spectral Response Acceleration at a Period of <br />1 second, SD1 0.646 <br /> <br />5.4.4 Seismically Induced Landsliding <br /> <br />Seismically induced landslides are triggered by earthquake ground shaking. The risk of this <br />hazard is generally greatest in the winter when groundwater levels are highest and surficial soils <br />are saturated. As with all slopes in the region, this risk is also present at the site to varying <br />degrees depending on the slope conditions and time of year. As noted above, the hillside located <br />to the southwest of the site is within a preliminary State of California Seismic Hazard Zone for <br />areas that may be susceptible to seismically induced landsliding. <br /> <br />Siting of the proposed structures in accordance with the recommendations provided in this report <br />is intended to mitigate the potential for adverse impacts from seismically induced landsliding.