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Non-Water Release Corrective Action Plan <br />North County Recycling Center and Sanitary Landfill <br />AU24.1294.00 | Non-Water Release Corrective Action Plan Update 9 <br />October 2024 <br />performance than previous procedures, including Bray and Rathje (1998). <br />The refuse cross-sections were analyzed to calculate the yield acceleration (ky) to achieve a <br />pseudo-static factor of safety equal to 1.0. The results of the pseudo-static slope stability <br />analysis are presented on Figures B-1 and B-2 (Appendix B) and are summarized in Table 3. <br />TABLE 3 <br />PSEUDO-STATIC SLOPE STABILITY ANALYSIS <br />FIGURE NO. DESCRIPTION OF ANALYSIS YIELD ACCELERATION, KY <br />B-1 Section A-A’ 0.10g <br />B-2 Section B-B’ 0.097g <br /> <br />Based on the yield acceleration values provided above, permanent seismic displacement <br />calculations were performed for the refuse prism cross sections in accordance with the <br />procedures described above. The results are presented in Appendix B, Figures B-3 and B-4. <br />The results of the calculations indicate negligible to approximately 1 centimeter of permanent <br />dynamic displacement of the refuse prism from the design PGA (which is greater than the MCE <br />design event) for the two cross sections analyzed indicating that the landfill is stable under <br />dynamic conditions. Therefore, significant dynamic displacement of the refuse prism is not a <br />reasonably foreseeable impact at this site. <br />4.1.5.4 Dynamic Landfill Final Cover System Analysis <br />Review of Detail 2, Sheet 5 of 5, Liner System Details, Preliminary Closure and Post-closure <br />Maintenance Plan, (Shaw, 2010) indicates that the final cover slopes for the landfill will be at an <br />inclination no steeper than 3:1 (horizontal to vertical) and consist of the following (from top to <br />bottom): <br />• 2-foot thick operations layer <br />• Geocomposite drain <br />• 60 mil HDPE geomembrane, double-sided textured <br />• Geosynthetic clay liner (GCL) <br />• 6-inch thick subgrade preparation layer <br />Review of the boring logs for the site indicates the predominant soil on the site ranged from a <br />silty sand to a sandy silt with some clay. The soil parameters used for the cover soil and <br />geosynthetic interfaces are presented in Table 2. <br /> <br />Review of the interface friction values (Table 2) indicate that the most critical interface is <br />between the geocomposite and the 60 mil double-sided textured HDPE. To evaluate the