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normal stress) and 36 degrees (under high normal stress) in the stress range expected along <br /> critical stability failure surfaces in the VLF. Weighting the internal friction angle to the normal <br /> stress levels expected along critical failure surfaces results in an internal friction angle of 38 to <br /> 40 degrees. The test results are presented in Appendix B. Shear tests were also conducted in <br /> nominal '/-inch ore materials. The test results from the '/-inch ore resulted in an internal angle <br /> of friction of 39 degrees,which is similar to the 1'/z-inch ore test results. These shear test results <br /> indicate that an angle of internal friction between 38 to 40 degrees can be used for ore that is <br /> nominally sized between 1%a and 3/ inches. These test results are within the range of published <br /> shear strength data for rock fill materials(Leps 1970), where the internal friction angles range <br /> between 39 to 50 degrees for similar sized materials under similar normal stresses. Based on the <br /> results of the shear tests conducted on the Cresson ore and published data, an internal friction <br /> angle of 40 degrees is suitable for the stability analyses. The in-place net density of the material <br /> is modeled at 110 pcf, which is consistent with that submitted previously to the DBMS. <br /> 4.11 Reclamation/Closure <br /> At closure, the Phase 5 VLF will need to be detoxified via rinsing. After detoxification, the <br /> Phase I, 11, 1II, IV, and 5 VLF side slopes will be regraded to overall 2.5H:1 V slopes. The <br /> reclaimed Phase 5 VLF configuration is shown on Drawing A600. <br /> 38 <br />