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Mountain Coal Company Exhibit 69 West Elk Mine Sylvester Gulch Facilities The facilities design criteria for the dewatering and treatment systems are summarized in Table 1. TABLET FACILITIES DESIGN CRITERIA Parameter Design Value Treatment Design Flow 2,000 gpm Hydraulic Design Flow 4,000 gpm Number of Treatment Process Trains 2 Treatment Design Flow per Train 1,000 gpm Hydraulic Design Flow per Train 2,000 gpm Design Influent Total Suspended Solids 1,000 mg/L Effluent Total Suspended Solids <25 mg/L Facilities Description Following is a description of the individual components of the Mine Dewatering and Treatment Facilities. Dewatering Pump Station and Treatment Building The Dewatering Pump Station and Treatment Building contains both the mine pumping equipment and the mine water treatment equipment. The Dewatering Pump Station portion of the building will consist of two 2,000 gallon per minute (gpm) deep well vertical turbine pumps. One deep well pump will be stored as a back-up/spare and the other will be mounted at the surface of the 18-inch cased borehole and will have a column depth of approximately 600 feet. The hole has been completed to the operational sump in the northeast corner of the LONE Tailgate. This operational sump will serve as the pump system wetwell. The pumps will discharge to three possible locations: the presedimentation basin, the recirculation borehole(s), and/or the treatment equipment. The recirculation borehole is a 12-inch cased borehole (already completed per MR 212) that is located approximately 100 feet south of the pump boreholes. The borehole is within the building footprint and will recirculate water through the sump. There are two 20-inch cased boreholes (completed per MR212) that will serve as alternate recirculation boreholes and/or boreholes for water level indicators. These holes are located near the dewatering borehole. Oc(. 1997TR83; Revised Mw /99R MR243 3