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<br />• Geotechnically stable <br />• Erosionally stable [sedi ent is not <br />transported past the footprint of the <br />area in quantities greater than <br />surrounding terrain - based on routine <br />observations and sediment control <br />management practices under the standard <br />operating practices of CC&V(G)] <br />• Can be revegetated, or covered with talus-like rock <br />• Safe for approved post-mining land use" <br />GAI completed static and pseudo-static slope stability evaluations of <br />the amended SGOSA, as proposed. Three critical facial cross sections <br />were chosen for structural analysis of the SGOSA. For the pseudo- <br />static analyses, the 0.8g peak ground acceleration (PGA) seismic <br />coefficient was used, as approved by the Division for Amendment No. 7. <br />The 0.8g PGA was accepted by the Division for application to "non- <br />hazardous" facilities (i.e. facilities which do not contain hazardous <br />materials, such as cyanide), which include the Valley Leach Facility <br />after detoxification, SGOSA and AGOSA. The slope stability <br />conclusions for the three critical facial cross sections are <br />summarized On Drawing #2 of Appendix 6. As stated on this drawing, <br />the minimum static Factor of Safety (FOS) for the reclaimed (2.SH:1V) <br />slopes exceeds 1.6 and the minimum pseudo-static FOS exceeds 1.3. <br />GAI also evaluated the stability of the first 300-foot thick end <br />dumped lift to be placed at angle-of-repose within the SGOSA. The <br />static FOS exceeded 1.0 for this lift. The GAI analyses of the SGOSA, <br />as presented in Appendix 6 to the Amendment No. 8 application, are <br />viewed as consistent with previously approved structural evaluations <br />and designs by the Division. In my opinion GAI has complied with <br />normally accepted standards of structural design and stability <br />evaluation. Further these design and evaluation conclusions are <br />faithfully summarized by CC&VG within Section 5.7.1.4 "Stability" on <br />page 59 of the "Project Description" within Volume I of the Amendment <br />No. 8 application. <br />Arequa Gulch Overburden Storage Area (AGOSA) <br />CC&VG states that the AGOSA will remain essentially the same under the <br />Amendment No. e application, as currently amended under the Amendment <br />