_GENERAL DOCUMENTS - C1981017 (234)

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north of Road A about one half mile west of the mine gate. The back wall of the stockpile varies in height from twenty to about fifty feet above the floor. The wall approaches vertical in places, and is covered by semi-consolidated coal fines. The floor of the facility is approximately three quarters of an acre in size. It too is covered in coal fines, with an average depth estimated at two feet. The pad is graded slightly to the south, toward Road A. Surface runoff from the area is directed to the Road A drainage ditch, which eventually reports to ponds located near the warehouse. Runoff is generated from the overland conveyor bench located immediately above the back wall, and from uphill areas. This runoff flows in an uncontrolled manner across the conveyor corridor and over the side of the back wall, causing large erosional gullies to form in the coal fines and in the underlying material . Surface flows continue across the pad bench, causing erosion of the coal fines, and transportation of these materials off the bench. Eventually, flow from approximately 90% of the bench area flows off the bench via a large gully that has developed above Road A. Stockpile M is located immediately below (south of) Road A, and just west of the warehouse area. The back wall forms the outside edge of Road A, and is characterized by steep, nearly vertical slopes on the order of thirty to fifty feet in height. The slopes are composed of Mancos Shale overlain by coal fines. The back wall exhibits gully erosion, but no large scale instability. The floor of the facility appears to be alluvial in origin, and is covered by an estimated depth of twelve inches or less of coal materials. Drainage from this facility is toward three ponds located in the south east corner of the stockpile area. There is not a defined drainage ditch or channel, so the runoff is generally heavily sediment laden. A berm composed of alluvial soils surrounds the facility on the south and west sides. The proposed reclamation concept is to restore the approximate original topography of both stockpile areas by accomplishing a moderate amount of grading work. The coal materials at each area would be pushed against the respective back walls. Beginning above the B stockpile, dozers would push material from north to south, reducing the height of the back wall by pushing it onto the bench to form a slope on the order of 2H: 1V. Grading would continue at the southern edge of the facility, which is immediately above Road A. The steep slope along Road A would be graded out to a shallower configuration. The outside portion of Road A would be pushed down onto the M stockpile floor to ameliorate the steepness of the back wall . Again, a 2H:1V slope angle is the goal . However, mass balance calculations will need to be done to ensure sufficient cut material is available to achieve this goal . The remnant of each bench would be ripped to enhance plant growth and encourage infiltration. Drainage channels will be constructed at each stockpile location in 4