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Cripple Creek & Victor Gold Mining Company Squaw Gulch Valley Leach Facility Design <br />a side slope of 1.6H:1 V was selected as the maximum ore side slope for the VLF that <br />would provide a FOS of 1.0 or greater. <br />Stability analyses were performed on the configuration of the ore shown on Drawing <br />A100 and with the piezometric surface conditions presented above. A total of 6 critical <br />stability sections were selected for the stability analyses. The locations of the stability <br />analyses are shown on Drawings A700 and A710. The majority of the slopes within <br />the VLF are buttressed by upsloping ground and will have enhanced stability. <br />Stability analysis results for each of the critical stability sections are summarized in <br />Table 5. The output from the stability analyses are presented in Appendix E.2. <br />As presented in Table 5, the stability sections indicate that the FOS values exceed the <br />prescriptive values outlined in Section 1.4 and are 1.3 and 1.5 or greater for <br />operational and reclaimed static conditions, respectively, and 1.0 and 1.1 or greater for <br />design accelerations of 0.14g and 0.08g, respectively. It is important to note that the <br />FOS values reported represent the operational ore side slopes varying between <br />1.6H:1 V and 2.5H:1 V. At reclamation, the ore side slopes will be regraded to a flatter <br />side slope of 2.5H:1 V, which will increase the overall long -term stability of the facility. <br />5.2 Settlement <br />5.2.1 PSSA Foundation <br />Settlement calculations were completed for the PSSA along the PSSA embankment. <br />Settlement calculations were not conducted for the PSSA bottom since it will be sited <br />on a prepared bedrock surface. Settlement along the PSSA embankment slope was <br />calculated using the numerical model Plaxis V8.2 (Plaxis 2007). Plaxis is a two - <br />dimensional, finite element program that is used to analyze the response of <br />geomaterials under applied loads. The PSSA embankment settlement was calculated <br />by "constructing" the embankment within the model and applying the ore loading from <br />the VLF. The embankment materials were modeled as a fine - grained rockfill with a <br />unit weight of 120 pcf and a stiffness of 4,375 psi. The rockfill unit weight was based <br />on typical values that have been measured for compacted rockfill materials at the site. <br />The rockfill stiffness was based on typical values encountered for the construction of <br />rockfill embankments and dams, as presented in Hunter and Fell (2003). The results of <br />the PSSA embankment settlement calculations are presented in Appendix C.7. The <br />results of the analyses indicate that the anticipated settlements along the PSSA <br />embankment will likely range from 0.6 to 9 inches under the applied ore loading. <br />These settlements are considered minor and are not anticipated to damage the PSSA <br />liner system. <br />5.2.2 VLF Foundation <br />Settlement calculations for the VLF foundation were primarily focused on the regraded <br />SGOSA slopes, since these slopes are anticipated to deform under the maximum ore <br />Project No.: 74201125G0 Page 30 <br />1 September 2011 <br />amec° <br />