COMPLIANCE INFO_JTD 9/3/2025 - Laserfiche WebLink

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3-11 the FSL property was made to determine which fault had the greatest impact on ground motions at the FSL site. Based on the results of this seismic characterization, it was determined the MCE is characterized by:  A near-field event of 6.90 Moment Magnitude (MW) on the Great Valley 7 Fault, located approximately 59.33 km away from the FSL site, generating a peak horizontal ground acceleration (PHGA) of 0.1351g (expressed as acceleration of gravity “g”).  A far-field event of 8.05 MW on the N. San Andreas Fault (SAO+SAN+SAP+SAS) system, located approximately 132.99 km away from the FSL site, generating a PHGA of 0.0970g. The peak ground motion response at the FSL site was estimated using empirical attenuation relationships taken from the Pacific Earthquake Engineering Research Center - 2014 Next Generation Attenuation West-2 Model. 3.1.3 Seismic Displacement Analyses Analyses of seismic displacements using the Mw 6.90 and the Mw 8.05 MCE events were performed to evaluate displacement / disturbance to the FSL final cover system (refer to Seismic Characterization Report in Appendix A). The results of the final cover analyses under the MCE peak ground motion, yielded displacements ranging from approximately 0.16-inches to 3.9-inches for localized displacement to the final cover system; and approximately 0.003-inches to 0.08-inches for displacement to the entire final cover system. The estimated displacements are considered “de minimis” damage, as it is less than one foot. However, this minimal displacement could cause some minor damage to the final cover system. The estimated theoretical displacements are considered minimal; however, for conservative purposes, the following assumptions were made to assess the FSL final cover system corrective action / repair costs:  Area of landfill disturbed conservatively assumed equal to 2-acres or 87,120-square feet.  Average depth beneath the disturbed landfill area conservatively assumed equal to 10-feet (ft) beneath a 5.0-ft ET final cover, for a total depth of 15-ft.  One-half (1/2) of the disturbed final cover soil is commingled with waste, and therefore deemed to be “dirty” final cover soil requiring landfilling as waste.  One-half (1/2) of disturbed final cover soil is “clean” cover soil and can be re-used for final cover repair / restoration.  Excavation, sorting, and separately stockpiling the disturbed waste mass and “dirty” final cover soil from the “clean” final cover soils is required.  Re-landfilling of waste and “dirty” final cover soils is required.  Replacement of the disturbed area with ET final cover soils (1.5-ft foundation soil layer, 3.5-ft ET soil layer) is required.  Placement of mulch and hydro-seeding of the repaired final cover area are required. It was assumed that on-site borrow soils would be used for the final cover repair. A corrective action cost of $569,071 was estimated for the Earthquake Causal Event. The cost breakdown is provided on Table 1 with stated assumptions and quantity takeoffs.