2007-06-29_PERMIT FILE - C1981022A (2)

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Section - 2.50.3 the performance standards under Rule 4.03 aze, therefore, not applicable. Road plan and profile . configuration is shown by a Facilities Detail Map, (Map series 2.05-M3x). Use as a haul road was limited to a short initial period of time during conveyor construction and then occasional use for emergency haulage if the conveyor is down. These limitations on use aze important because road design and construction are to be based on geometric criteria appropriate foz the anticipated volume of traffic and weight and speed of vehicles. A 72-foot wide road with passing sections would not be appropriate for long-term use as a haul road. Given, however the intended short-term and occasional use as a haul road, the haul road width and configuration aze adequate. Long-term and predominant use of the road will be as an access road for transportation of men, equipment, and supplies to and from the mine portals. The road design is consistent with and acceptable for long-term use as an access road. The first segment of the Sanborn Creek Mine haul road extends from the Sanborn Creek Mine portals to the west approximately 1,300 feet. This segment is located north of the relocated railroad grade. A portion of this segment is located on the old railroad sub-grade which is on grade with no embankment slopes and a cut slope to the north. The road continues to the west between the cut slope to the north and the relocated railroad grade to the south. This road segment is relatively flat (< 5 percent grade) and narrow, with one-way traffic from the portals to a turn-out azea neaz the mine water treatment pond and atwo-way passing zone at it's western end. The second segment of the Sanborn Creek Mine Haul Road extends approximately 800 feet from the end of the first section just west of Sanbom Creek to the East Yard. This segment is constructed on fill along the route of the old road entrance to the East Yard with a cut slope on the north side and an embankment on the south. The road embankment was constructed on an old haul road previously used for coal haulage from the old Bear No. ]and 2 Mines to the Somerset Mine. Except for the two-way passing zone at its eastern end, this segment is relatively narrow and limited to one-way • traffic. Road grade for this section is approximately 5 percent. The third segment of the Sanborn Creek Mine haul road extends approximately 1,900 feet from the west end of the second segment at the east end of the East Yard to a point where the road joins the second segment of the main entrance road near the dump station. This road segment traverses the East Yard area and is of sufficient width to allow two-way traffic. This segment also has aturn-out near the East Yard Pond and ties in with the East Yard coal stockpile area. This segment of road is mostly on grade and relatively flat (< 5 percent grade) and open except on it's eastern end where it is confined between the cut slope to the north and the fill embankment on the south. A new access road segment was constructed south of the Sanborn Creek Mine overland conveyor to divert traffic around the East Yard coal stockpile area. The access road extends from the second segment of the main entrance road to the east approximately 1,000 feet where it ties into the third segment of the Sanborn Creek Mine haul road. In this area, a section of the conveyor is elevated as a traffic underpass.. The access road is generally on grade except for a small fill in the tie-in azea on the outslope of the East Yazd. Drainage control measures for the first two segments of the Sanborn Creek Mine haul road include roadside ditches and uoss-culverts as shown on a Facilities Detail Map (Map series 2.05-M3x). Drainage control for both the third segment of the haul road and the associated access road is provided by existing drainage and sedimentation control measures for the East Yard area. The Sanborn Creek Mine haul road and conveyor corridor cross over Sanborn Creek. A 3G-inch diameter steel culvert, placed in the road embankment during construction, is designed to safely pass the 10- year, 24-hour design flow for this ephemera] drainage. The outlet of the .Sanborn Creek culvert crossing ties into an existing Highway Department culvert. A second 36-inch diameter culvert was installed in the haul road near the Somerset Mine portals. This culvert will carry run-off from the • portion of the haul road east of Sanborn Creek and upland areas. Rock or concrete headwalls have been constmcted to protect the inlets of the 36-inch culverts from erosion. A riprap channel was also constructed at the outlet of the second culvert to minimize erosion as illustrated by the Drainage and Sediment Control Map, (Map 2.05-M4). Design calculations for all drainage structures are provided in Exhibit 2A5-E3, Drainage and Sediment Control Plan. TR-43 2.05-26 Revised August 2003