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Mountain Coal Company Exhibit 69 <br />West Elk Mine Sylvester Gulch Facilities <br />The treatment portion of the building will house several pieces of treatment <br />equipment. The equipment will include two 1,000 gpm conventional high-rate <br />flocculation and sedimentation units, chemical feed equipment, and chemical <br />storage equipment. <br />Presedimentation Basin <br />A concrete-lined Presedimentation Basin will be constructed to provide mine <br />water settling prior to treatment. The basin will consist of two cells for <br />redundancy. Each cell will be 16 feet (interior dimension) wide, 78 feet (interior <br />dimension) long, and 12 feet deep (water depth) and there will be a common wall <br />between cells. Two baffle walls are provided in each cell to eliminate flow short- <br />circuiting and to promote even flow distribution. The effluent weir will provide <br />even flow splitting to the subsequent treatment units. Sludge will be collected at <br />one end of the basin and periodically washed to the Sludge Drying Lagoons. <br />Decant Return Basin and Pump Station <br />Liquid decant will be generated at the Sludge Drying Lagoons (see description <br />below) when supernatant, or settled water at the water surface, is withdrawn. As <br />such, a decant return basin will be provided to serve as a flow equalization basin <br />and to return the water to the head of the plant (Presedimentation Basin) for <br />further treatment. The Decant Return Basin will include two submersible pumps. <br />The structure will be a package, buried concrete basin and pump station. Access <br />will be restricted by a lockable access hatch. <br />Sludge Drying Lagoons <br />Sludge generated by the treatment facilities, which will consist primarily of fine <br />grain silt and clay, will be discharged to the Sludge Drying Lagoons. The Sludge <br />Drying Lagoons will reduce the water content of the sludge, therefore reducing <br />the volume of sludge that must be disposed. The total solids percentage of the <br />sludge discharged to the lagoons will typically be 1 to 4 percent. The sludge will <br />be allowed to settle in the lagoons and supernatant (settled water at the water <br />surface) will be withdrawn. The Supernatant will be discharged to the Decant <br />Return Basin. After a sufficient drying period is provided in the lagoons, the <br />dried sludge will be removed by excavating equipment for disposal at an existing <br />refuse pile at the West Elk Mine. <br />Oc(. 1997TRR3r Revised Ma_v 799N MR243 <br />4 <br />