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Mountain Coal Company Exhibit 69 <br />West Elk Mine Sylvester Gulch Facilities <br />• approximately 25 feet wide will occur over approximately 1,200 feet of the <br />distribution line routings. Topsoil salvage and excavation/fill quantities associated <br />with construction of the distribution line support structures are discussed in the <br />paragraphs below. <br />Roads <br />r 1 <br />U <br />Road construction includes construction of approximately 4,600 feet of new 24-foot wide <br />access/haul road to the substation and shaft sites, widening (to 24 feet from 14 feet) and <br />upgrade of approximately 5,000 feet of the existing Sylvester Gulch access road to haul <br />road standards, and construction of approximately 11,000 feet of new 14-foot wide light <br />use road to provide maintenance access to the existing water tank and new transmission <br />and distribution power lines. All roads will be designed and built in accordance with <br />Colorado Mined Land Reclamation Board (CMLRB) Rule 4.03 and American Association <br />of State Highway and Transportation Officials (AASHTO) standards for grade, <br />sideslopes, berming, drainage, and erosion and sediment control practices. A three foot <br />high guazdrail will be built along approximately 2,900 feet of the shaft site access road. <br />Safety berms will be constructed for embankments not protected by guardrail. <br />The road to access the shafts site will be built to haul road specifications and will be <br />surfaced with 8 inches of compacted road base. Light-use roads will be surfaced with 8 <br />inches of compacted road base. Roadway ditches and cross drain culverts will be built to <br />carry the peak flow from the 10-year, 24-hour storm event. Culverts for road crossings of <br />Sylvester Gulch and major tributaries will be built to carry the peak flow from the 100- <br />year, 24-hour storm event. Culvert and ditch designs are included in Exhibit 66. <br />Svlvester Gulch Road Modification <br />The upgraded and modified Sylvester Gulch road will have an average grade of <br />7.6% with a maximum grade of 10%. Typical cut slopes will be 2:1. Embankment <br />fill slopes will vary from 2:1 to as steep as 0.5:1 at engineered embankment <br />locations. Approximately 1,700 feet of engineered embankments will be built in <br />order to avoid Sylvester Gulch channel relocations and minimize impacts on <br />Sylvester Gulch wetland and riparian areas. Two slide aeeas and one uphill wetland <br />area are cut by this road alignment. Slope stability analyses have been performed for <br />these areas indicating minimum safety factors of 1.3 in all areas. Approximately <br />2,000 cubic yards of the existing subsoil pile located at the current intersection of the <br />main hauUaccess road and the Sylvester Gulch Road will also be excavated as pan of <br />the road realignment. This material will be moved to a different subsoil pile or <br />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 />I • <br />$ Nav. /996PR07R; Revised May /997MR216: <br />RevsedJul. 1997MR219 <br /> <br />