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Talus slope stability. Talus slope stability may be affected in local areas where borrow <br /> is obtained. Friction angles for coarse grained rock fills has been analyzed by Maraehi'for <br /> - various confining stresses. For low confining stresses, typically less than 100 psi,similar <br /> to the Lake Emma area,friction angles may be on the order of 45*(Appendix I-B). IN nite <br /> slope stability analysis, therefore, indicates that excavations steeper than 1 horizontal to I <br /> vertical will probably exhibit ravelling until a slope develops that is similar to that which <br /> currently exists. By limiting the height of cuts large slope movement should not occur. <br /> Excavation of talus slopes will be done in such a manner that all vertical faces will be less <br /> than 10 feet. Slope movement associated with this height of slope, even if they occur, <br /> should not jeopardize the outlet by plugging the canal. As shown on the Exhibit CO map, <br /> the only talus slope nearby the diversion is located to the west of the channel. <br /> Access road. The access road is pre-existing and serves other patented claims in the <br /> area. It will therefore remain open following reclamation of Lake Emma. <br /> Terry Tunnel <br /> The Terry Tunnel area will be reclaimed and revegetated at the end of the life-of-mine <br /> operations. As part of the reclamation program, all trash and refuse at the site will be <br /> removed or buried. Refuse existing at the surface will be picked up and placed in the <br /> existing ponds for burial. If necessary, the pond excavations ar the site will be enlarged to <br /> facilitate burial. All refuse and trash will be buried with at least two feet of material prior to <br /> revegetation. Suitable material is available at the Terry Tunnel site for covering the refuse <br /> and trash to be buried Material will be made available primarily by excavating and grading <br /> of the pond areas and embankment sideslopes. A main priority for reclamation at the Terry <br /> Tunnel site will be to reclaim the site without further disturbance of undisturbed areas for <br /> borrow or plant materials. <br /> Revegetation of this area will be conducted after final grading. Fertilizer and mulch will be <br /> used as amendments. The seeding techniques and amendments to be used will be the same <br /> as described above for Lake Emma, except it is known that existing materials used as <br /> revegetation media are low in plant nutrients,and for that reason specific fertility testing of <br /> the final graded surface will be conducted just prior to revegetation. Analyses of samples <br /> will be conducted by the State Soils Testing Laboratory at Colorado State University. <br /> Revegetation will employ the "Alpine Mix' seed mixture(at approximately 120 seeds per <br /> square foot, broadcast)and specific seeding methods described laser in Table E-3. The <br /> mixture differs slightly from the mix proposed for the Lake Emma area owing to a <br /> difference in elevations. <br /> The road up Eureka Gulch is public and will remain in place after final reclamation. <br /> American Tunnel <br /> Upon final redamation,the portal entrance at the American Tunnel will be sealed to prevent <br /> drainage(see Exhibit G). Disturbed areas within the current permit area will be reclaimed <br /> and revegetated. Surface facilities will be dismantled and removed from the site. Final <br /> reclamation of the American Tunnel site is not expected to take place for many years. After <br /> surface facilities have been dismantled and removed, and all other materials removed or <br /> tMaraehi,DA,Chan,CX..Seed,HB.,and Duncan,J.M. 1969.Strength and deformation characteristics <br /> of rock fill materials, report No. TE-695 to State of California, Dept. Water Resources, University of <br /> California,Berkeley. <br /> J <br /> Consolidated Permit Application E:5 1-13-87 <br />