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-34- During mining, fine coal processing waste from the wash plant is pumped as a slurry into abandoned mine workings. The water which is decanted from the slurry disposal areas is recycled back to the wash plant in a closed system. This system prevents the build up of degraded water within the mine and the contamination of surface and ground water systems. The coarse coal processing waste is disposed of in an approved disposal site adjacent to the Delta County Landfill near Hotchkiss. This disposal site is located in the "dobes", a sparsely vegetated exposure of the Mancos Shale. The Mancos Shale at the disposal site is saline and is composed of shales and silty shales with very low permeabilities. Disposal of coal processing wastes within this site will not affect the quantity or quality of ground water, given the impermeability of the site materials and the lack of ground water at the site. Compacted waste will be covered with the required 4 feet of non-toxic cover. Surface Water The Hawk's Nest Mine surface facilities are located along the North Fork and the mine workings extend below small ephemeral tributaties to the IVorth Fork. The mines will minimally impact the quality and quantity of surface water tributary to and water within the North fork of tiie Gunnison River. The sediment and drainaye control system has been desiyned to minimize the impacts of the mining operation on the quality and quantity of surface water. This system consists of lj a series of diversions upslope of the disturbed areas to route undisturbed drainage away from the surface facilities, 2) a series of diversions and collection culverts to route surface water from disturbed areas to treatment areas, and 3j five sediment ponds to treat water from disturbed areas prior to discharge to surface streams. This sediment and drainage system has been designed to handle the 10-year, 24-hour peak flow storm event. All of the sediment ponds will satisfactorily retain both sediment storage and inflow volumes. Quality and quantity of surface water retained in sediment ponds will be impacted due to evaporative loss. These impacts will be minimal since water will be discharged after a short retention time and will meet NPDES effluent limitations at the tune of discharge. The Hawk's Nest Mine will slightly impact the quantity of surface water through the diversion of surface water to underground workings. The existing mine experiences continuous mine inflows beneath Hawk's Nest Creek and Coal bank Gulch. The rates of inflows fluctuate seasonally with the highest inflows lagging behind the period of the highest surface flows in the overlying streams. These inflows are minor, varying between a few gallons per minute to a trickle over the entire fracture length. To date, no inflows have occurred in workings which have been subjected to complete subsidence by pillaring and long walling.