Laserfiche WebLink
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 10 <br />October 2024 <br />stability of the proposed landfill cover system, a stability analysis was performed for the landfill <br />slopes at an inclination of 3:1 (horizontal to vertical). The analysis used the infinite slope <br />method using the soil parameters presented in Table 2. The analysis assumed a potential <br />failure plane through the most critical interface on the slope. The yield acceleration (ky) was <br />calculated for the slope cover configuration. The calculations are presented in Figure B-5 <br />(Appendix B) and summarized in the following Table 4: <br /> <br />TABLE 4 <br />COVER SYSTEM SLOPE STABILITY RESULTS <br /> FIGURE NO. KY <br />Failure along most critical slope cover interface B-5 0.15g <br /> <br />Based on the yield acceleration value provided above, permanent seismic displacement <br />calculations (Figure B-6, Appendix B) were performed for the cover system in accordance with <br />the procedures described in Bray, et. al, 1998 for cover stability analysis. The results of the <br />calculations indicate less than 1 inch of permanent dynamic displacement under the loading of <br />a PGA of 0.15g (which is greater than the MCE design event). In accordance with CalRecycle’s <br />BMPs, 2010, Table 2, page 5, this magnitude of displacement is considered de minimus for <br />ground motion and the cost for corrective action is not required. <br />Based on our calculations, significant impacts resulting from dynamic displacement of the final <br />cover under loading greater than the predicted MCE event are considered outside of the <br />definition of a reasonably foreseeable impact. <br />4.1.6 Summary of Impacts from Seismic Hazards <br />In summary, the potential for impacts to the NCRCSL from ground rupture, seiche, tsunami, <br />liquefaction/dynamic settlement, or refuse/cover system slope failure resulting from the design <br />MCE is considered negligible and outside the definition of a reasonably foreseeable impact. <br />4.2 Precipitation Impacts <br />Storms causing damage to the cover, exposure of waste, clogging of the drainage system, <br />erosion or failure of slopes, are all possible due to excessive amounts of water. Therefore, <br />excessive precipitation is a foreseeable casual event that can affect a landfill. Landfills are <br />required to maintain systems to control run-on and run-off due to precipitation throughout the <br />active and post-closure period. The standard for Class III Landfills, such as the NCRCSL, is to <br />design for a 100-year, 24-hour storm event, which is defined as a one percent chance of <br />occurring in any one given year (1/100 = 0.01 = 1%). <br />The data from the National Oceanic and Atmospheric Administration (NOAA) Atlas 14 <br />Precipitation Maps (see Appendix C) was reviewed to see if the point precipitation values have <br />changed since the original NWRCAP was prepared. Upon review, most of values remained the