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classification from this table that best matches the materials in terms of description. The native <br /> alluvial material is best classified as sand and gravel with a mixed grain size. From the SME <br /> table, sand and gravel with a mixed grain size has an internal angle of friction of 45 degrees and <br /> no cohesion. Given the height of slopes involved, no overburden was assumed. <br /> The post-mined slope in both maximum mining condition and reclamation condition was <br /> modelled. The WRL at construction slopes and final slopes was also modeled. Both were <br /> analyzed using Bishop's Method of Slices in GALENA software. The phreatic surface from a <br /> local water table was assumed to be well below the excavation and reclamation slopes. The <br /> piezometric surface was assumed to be along the natural drainage surface, at the bottom of the <br /> WRL, since it is free-draining. A seismic model was developed and analyzed for the WRL as it <br /> is uphill of a public road. <br /> Mined Slope <br /> The post-mined slope was modeled in two conditions: immediately at the end of mining and <br /> following reclamation (Figure 16). At the end of mining, this true highwall will exist in a <br /> combination of large size colluvium and competent gneiss bedrock or as exclusively bedrock. <br /> The active highwall—a total of 25-feet high—will have an overall slope angle of 2.OH:LOV, <br /> with maximum individual bench angles of 0.1H:1.OV, or near vertical. Where it occurs, the <br /> colluvium covers the gneiss at an average depth of 160 feet. Therefore, geotechnical information <br /> such as joint orientation will not be obtained until over 10 years into the life of the mine. At that <br /> stage, the Young Ranch Resource Quarry will begin submitting geotechnical reports as required <br /> by the Division as do other quarries in the state. Until that time, the geotechnical stability of the <br /> gneiss will be based on textual values as those used in this analysis. <br /> The second condition of the post-mining slope is when it has been backfilled with crusher fines <br /> and reclaimed. At that stage, it will have an overall slope of 2.OH:LOV and a localized slope of <br /> the same amount. The crusher fines material properties are based on Lewicki experience with <br /> crushed rock in this area. <br /> Young Ranch Resource <br /> December 2021 RULE-6.5 a Lewicki& Associates <br />