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0 / Method <br />of <br />1 N <br />Typical steps in a seismic slope stability analysis include: <br />1. A site-specific seismic hazard evaluation to determine the MPEs for faults that can <br />impact the site and corresponding magnitude of peak horizontal ground <br />acceleration (kora,) and acceleration time history. <br />2. A pseudo -static slope stability analysis using the PCSTABL computer program to <br />determine the yield acceleration (ky1eld). <br />3. If kms is greater than ky;eld, a site response analysis using the SHAKE computer <br />program to determine an average horizontal equivalent acceleration (HEA) time <br />history for the critical failure mass associated with the yield acceleration. <br />4. A Newmark analysis, which involves the double -integration of the average HEA <br />values that are in excess of the yield acceleration, to determine the permanent <br />displacement. <br />The analysis presented herein satisfies Paragraph (f)(5)(D) of Section 21750 of 27 CCR. As <br />discussed below, for Module 1 of FSL, since kms is significantly lower than ky1eid, <br />performing Steps 2 and 3 were not required. <br />40 4.3 Seismic Hazard Evaluation <br />EMCON/OWT used the consulting services of Dr. Norman Abrahamson, who is a <br />renowned Engineering Seismologist, to perform a site-specific seismic hazard evaluation <br />for the design of Module 1 at FSL. Dr. Abrahamson's seismic hazard report is presented <br />in Attachment 2. <br />Table 1 below presents a summary of MPE ground motions from the various faults that <br />can impact the FSL site. As can be seen from Table 1, the kms value is 0.054g. <br />Table 1 — MPE <br />Ground Motions for the North County Site <br />Fault <br />Closest Distance <br />(km) <br />MPE <br />Magnitude <br />Median Horizontal <br />PGA (g) <br />Central Valley Coast Range <br />62 <br />6.5 <br />0.052 <br />Greenville <br />76 <br />6.3 <br />0.028 <br />Calaveras <br />96 <br />6.6 <br />0.027 <br />Hayward <br />106 <br />7.0 <br />0.033 <br />San Andreas <br />135 <br />8.0 <br />0.054 <br />® \\SACRFPI\COMMON\sacDP\2002\PRJ\PJ8\83\835608.2bz.doc EMCs®w®w% Inc. <br />Rev. 0, 07/31/02 <br />4-2 <br />