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Mountain Coal Company Exhibit 69 <br />West Elk Mine Sylvester Gulch Facilities - <br /> <br />No active channel relocation is required, and the total wetland impact caused by the <br />road upgrade estimated to be 0.44 acres. Wetland impacts will be mitigated <br />according to a plan approved by the U.S. Army Corps of Engineers. <br />Retained slopes will be of a geogrid reinforced earth design, or similar, built at <br />varying slope. Total excavation for this road section is approximately 15,600 cubic <br />yards of which approximately 8,400 cubic yards is topsoil which will be salvaged and <br />stockpiled. Total fill requirements are approximately 97,000 cubic yards of which <br />7,200 cubic yards will come from excavated material and approximately 89,800 <br />cubic yards will be imported or come from other portions of the project. <br />Approximately 1700 feet of three foot high guardrail will be installed on this section <br />of road. <br />Ventilation Facility Road <br />• <br />The new access/haul road to the shafts site will have an average grade of 7.4% with <br />a maximum grade of 10%. Typical cut slopes will be 2:1 except where the road <br />parallels the shafts site. Cuts in this location will be in rock and will be steepened to <br />approximately 70 degrees. Typical embankment fill slopes will also be 2:1, but will <br />be steepened to 1.5:1 for approximately 300 feet adjacent to the sediment pond and <br />lower bench at the shafts site in order to minimize encroachment on the sediment <br />pond. Embankment slopes for the Sylvester Gulch crossing will be 1:1 (see below). <br />Total excavation for this road, up to the return shaft and including the Sylvester <br />Gulch crossing (see discussion below), is 40,000 cubic yazds of which approximately <br />17,000 cubic yards is topsoil which will be salvaged and stockpiled. Approximately <br />115,000 cubic yards of fill is required for this section of the access/haul road, of <br />which 23,000 cubic yards will come from excavated material and 92,000 cubic yards <br />will be imported or come from other portions of the project. <br />A 75 foot high (maximum) embankment will be built for the crossing of Sylvester <br />Gulch. The height of this embankment is dictated by the slope of the road required <br />to access the shag sites. Construction of the embankment will utilize a geogrid <br />reinforced earth design, or similaz, built at approximately 1:1 slope. Three foot high <br />guazdrail totaling approximately 700 feet will be installed along both sides of this <br />embankment. Fill required for the embankment crossing is included above. A <br />structural plate arch culvert, approximately 250 feet long will be placed in Sylvester <br />Gulch, designed to carry the 100-yeaz, 24-hour peak flow from the upstream <br />watershed. <br />~~ <br />Approximately 400 feet of retaining wall will be built where the road parallels the <br />intake shaft bench. The retaining wall will be constructed with polymer geogrid <br />reinforcement (e.g., TensazrM) and segmental block facing units (e.g., KeystonerM <br />walls or equivalent) similar to the retaining wall between the intake shaft and exhaust <br />shaft benches. A three foot high guardrail will be placed at the top of this retaining <br />9 Nov. /996 PR07R; RevitedM°y 1997MR216; <br />RevisedJuL l997MR219 <br />