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sample locations are shown on Exhibit 9-4, Postmine Topsoil and Spoil • <br />Sample Locations. <br />The mean topsoil replacement depth for the July 1984 through August 1986 <br />reclamation period was 1.54 feet. Fourth, the actual topsoil <br />replacement volume was determined to be 324.9 acre feet (1.54 feet x <br />211.0 acres). Fifth, the actual quantity of topsoil salvaged during the <br />July 1984 through August 1986 period was determined to be 345.9 acre <br />feet (324.9 acre feet replaced plus 21.0 acre feet stockpiled). Lastly, <br />the actual volume of topsoil salvaged (345.9 acre feet) was compared to <br />the projected topsoil salvage volume (301.5 acre feet). The difference <br />(345.9 - 301.5) is 44.4 acre feet or 14.7 percent (44.4 acre feet/301.5 <br />acre feet). Consequently, the proposed topsoil salvage depths presented <br />in the July 1984 topsoil balance should be increased by 14.7 percent for <br />the remaining life-of-mine topsoil salvage area. These adjusted topsoil <br />salvage depths and associated volumes for each soil map unit are <br />presented for each five year mine block in Tables 9-4-4 and 9-4-5. <br />Topsoil volume figures presented in Tables 9-4-4 and 9-4-5 have been <br />adjusted for 1) soil inclusions in map units and 2) brush clearing. <br />Unsuitable topsoil inclusions at Seneca comprise from 0 to 15 percent of <br />the various map units and generally include sandstone and shale outcrop <br />areas and soils with greater than 40 percent coarse fragment contents. <br />Second, "brush" (Gambel's oak, service berry, chokecherry, mountain big <br />sagebrush and aspen) clearing techniques utilizing a standard dozer <br />blade typically results in an approximate three-inch topsoil loss. <br />Topsoil Replacement Area <br />Topsoil will be replaced on the areas shown on Exhibit 9-3, Topsoil <br />Balance Plan which were all disturbed by mining after the Colorado Rules <br />and Regulations were approved (July, 1976). Pre-law haul roads which <br />are still being utilized are also included for topsoil replacement. <br />Topsoil will not be replaced within the high water line of permanent <br />postmine impoundments. <br />9-34 Revised 10/01/86 <br />