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Mountain Coal Company Exhibit 69 <br />West Elk Mine Sylvester Gulch Facilities <br />Other features of the shaft sites include a permanent topsoil storage pile above the <br />exhaust shaft bench, a permanent retaining wall and stairway between the two shaft <br />benches, a third benched area below the intake shaft bench for construction staging, a <br />stormwater surge basin above the site, Clearwater diversion ditches and culverts to the <br />north and south of the site, access/haul roads to the various benches, stotTrtwater/ <br />sediment control ditches within the site, and a lined sediment control pond located at the <br />lower end of the site. <br />The total disturbed area for the shafts site benches, including local roadwork and drainage <br />facilities, and the sedimentation pond, but excluding local roadwork, the topsoil storage <br />pile, is approximately 8.9 acres and a small 0.05 acre wetland will be filled in. <br />Excavation of approximately 84,200 cubic yards of material will be required, of which <br />approximately 29,000 cubic yards is topsoil to be salvaged and stockpiled. All of the <br />55,500 cubic yards of subsoil excavated, plus approximately 105,000 cubic yards of <br />imported material will be used as fill material for the shaft site benches and sediment <br />pond berms. Imported material will come from other areas of the project, or from off site, <br />as needed. All of the benches at the shafts site will be surfaced with a 20-inch layer of <br />compacted subbase and base totaling approximately 11,400 cubic yards. <br />Topsoil <br />A permanent topsoil storage pile with a maximum storage volume of 46,000 cubic <br />yards will be located above the shaft benches. The volume of this stockpile is <br />adequate to store an average 24 inch topsoil depth stripped from the shaft site <br />disturbed area of 8.9 acres plus additional topsoil generated during road building. <br />Harvestable timber within the site, typically 8" to 12" dbh, will be cut and removed. <br />The remaining brush will be crushed and/or stripped and shredded and incorporated <br />into the topsoil. The topsoil storage pile will be mulched and hydroseeded as soon <br />as possible after completion of the stockpile. Sediment and drainage control for the <br />topsoil storage pile will be achieved through the use of Clearwater diversion ditches, <br />straw bales, silt fence, etc., where appropriate, until vegetation is reestablished, <br />warranting removal of the temporary measures. Runoff from the topsoil storage pile <br />will be tributary to the sediment control pond for the site. <br />Retaining_Wall <br />The retaining wall between the intake shaft and exhaust shaft benches will be <br />constructed with polymer geogrid reinforcement (e.g., TensarT"') and segmental <br />block facing units (e.g., KeystoneTM walls or equivalent) similar to other recent <br />construction at the West Elk Mine. Retaining wall dimensions are approximately <br />35 feet high by 380 feet long. A three foot high guardrail will be installed along the <br />top of the retaining wall and a four foot wide steel staircase will provide far foot <br />traffic between the two benches. Guardrail will also be installed along the south <br />2 Nov. 199h PR07R; Revived Mnv 1997 MR2Ih <br />Revived Ju/. 1997 MRll9; Revised Jtme 2003 MR297 <br />