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~• 7. Spread topsoil to an even depth of 12" to 18" as called for by the MdcR plan. <br />8. Seed and mulch as called for by the MdcR plan. <br />9. Leave all areas free draining and provide erosion protection for seed on <br />steep slopes as required by the MdcR plan. <br />V. <br />A. GeneraL• <br />Three (3) critical areas outside of the Landslide Boundary were investigated for <br />past reclamation stability. These include the main access road at Station 40+00, <br />the freshwater and runoff ponds, and the road through the rock cut. ':Material <br />properties assumed for the past reclamation state were the same as those cited in <br />Section IV-C herein. <br />B. Reclamation at Access Road, Station 40+00: <br />Station 40+00 is a critical cross section of the proposed access road. It lies outside <br />the landslide boundary but is characterized by natural slopes of approximately 2:1 <br />or steeper (Refer to Exhibit 7). As opposed to those areas within the Landslide <br />Boundary, the natural soils in this location appear to be unsaturated. For this <br />reason, dewatering has not been planned for this area. <br />Stabilities were investigated assuming this section to be returned to its <br />approximate original contours with backfill material compacted to 85% of the <br />maximum Standard Proctor Density. The minimum Factor of Safety obtained for <br />this case was 2.11; this is high enough to ensure post reclamation stability in this <br />cross section. <br />The recommended procedure for returning this cross section to its approximate <br />original contours is consistent with previously cited backfill measures. The <br />bituminous concrete pavement and shotcrete structures should be removed and <br />disposed and the section should be backfilled in uniform layers approximately 8" in <br />thickness. Each layer should be compacted to 85% of maximum Standard Proctor <br />Density. The area should be evenly covered with topsoil to a minimum depth of 12" <br />to 18" to bring the final grade to its approximate original contours. Seeding and <br />mulching should be according to the M6cR plan. <br />C. Reclamation of Freshwater and Runoff Ponds: <br />The proposed freshwater ponds and various runoff ponds are located in naturally <br />flat portions of the project FW#1 and MB#1 are located on a large natural bench <br />(at an approximate elevation of 6300) above the valley floor and approximately 200 <br />feet below the proposed portal bench. bIB#2 end MB#3 ere located on the valley <br />floor at an approximate elevation of 6100. No potential slope stability problems <br />are expected once these relatively flat contours have been regained. <br /> <br />11 <br />