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Mountain Coal Company Exhibit 69 <br />West Elk Mine Sylvester Gulch Facilities <br />or relocated on the same pile. The existing drainage ditch will be restored such that <br />drainage from the subsoil pile continues to flow to existing MB-2R. <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 <br />and stockpiled. Total fill requirements are approximately 97,000 cubic yards of <br />which 7,200 cubic yards will come from excavated material and approximately <br />89,800 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 />The new access/haul road to the shafts site will have an average grade of 7.4% with <br />a maximum grade of ]0%. 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 <br />to approximately 70 degrees. Typical embankment fill slopes will also be 2:1, but <br />will be steepened to 1.5:1 for approximately 300 feet adjacent to the sediment pond <br />and lower bench at the shafts site in order to minimize encroachment on the <br />sediment pond. Embankment slopes for the Sylvester Gulch crossing will be 1:1 <br />(see below). Total excavation for this road, up to the return shaft and including the <br />Sylvester Gulch crossing (see discussion below), is 40,000 cubic yards of which <br />approximately 17,000 cubic yards is topsoil which will be salvaged and stockpiled. <br />Approximately 115,000 cubic yards of fill is required for this section of the <br />access/haul road, of which 23,000 cubic yards will come from excavated material <br />and 92,000 cubic yards 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 shaft sites. Construction of the embankment will utilize a geogrid <br />reinforced earth design, or similar, built at approximately 1:1 slope. Three foot high <br />guardrail 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-year, 24-hour peak flow from the upstream <br />watershed. <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 />9 Nov. /996 PR07R; Revived Mnv 1997 MR216 <br />Revie~ed Jul. 1997 MR279; Revie~ed June 1003 MR297 <br />