2011-01-13_REVISION - C1981038 (8)

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documented inflows of 200 gallons per day. This inflow gradually slowed once this perched aquifer was completely dewatered. Inflows during 1991 failed to produce over 3 gpm for any significant period of time. Because the portals at the Bowie No. 1 Mine were sealed in 2001 and the Bowie No. 1 West Mine portals were sealed in 2000, there is no current information on mine inflows. BRL has established an extensive monitoring system to monitor water levels in colluvial/alluvial deposits in the permit area and in the alluvium of streams overlying mine entries. Permeability tests on colluvium in the East Roatcap Creek drainage averaged 7.2xl 02 ft/day. No significant water level fluctuations have been noted in conjunction with mine inflows. Mine inflows in the mains underlying East Roatcap Creek averaged less than 1 gpm from 1987 to 1993. The permeability of the coal aquifer was measured in 1986 at 1.4x102ft/day. This insignificant aquifer has yet to make a visible contribution to mine inflows. BRL imported water for dust suppression from their wells in Steven's Gulch. In 1983, for example, the operator estimated that approximately 6.24 million gallons of water is consumed as moisture on the coal, 0.5 million gallons is consumed through increased humidity in the ventilation air, and less than 0.5 million gallons is lost through seepage into the floor of the mine. Surface Water - The Bowie No. 1 Mine area will not significantly affect the local surface water hydrology or the regional hydrology. Sediment control measures will ensure protection to stream quality. No mine water will discharge from the portals and no water will be withdrawn from the creek. An overland ditch will divert water into West Roatcap Creek thus bypassing the Bowie No. 1 West Mine site. Clean water diversions above the main facilities minimize surface water runoff through the site. Mine inflows under and adjacent to the creek are predicted to be insignificant. A brief discussion of sediment control measures, subsidence impact mitigation, surface water inflow predictions and water augmentation plans follow. The Bowie No. 1 mine plan is designed to minimize the impacts of the project on the surface water hydrology of the region. Disturbed area drainage from the East Mine benches, parking area, west portal fill, and loadout site is collected and treated on the site. Four sediment ponds collect disturbed-area drainage from the mine benches. Another pond controls sediment generated by the underground development waste pile. One pond controls drainage from the run-of-mine stockpile area, and two ponds collect drainage from the disturbed areas of the loadout, truck scales, and highway coal stockpile area. The West Mine portal bench area drained to one sedimentation pond except for exempted portions of the fill face which had a small area exemption waiver. With the reclamation work at the West Mine portal bench area, the backfilled and graded area now drains to two sedimentation ponds. A system of lined and unlined ditches conveys waters from the disturbed areas to the ponds. The mine operator has applied for and/or obtained the appropriate NPDES permits. Effluent quality from the sedimentation ponds will be monitored to determine permit compliance. Subsidence effects have the potential to impact any or all springs, seeps, and ponds within the affected permit area. In order to protect water resources but still allow mining, the operator has developed a subsidence damage preventative mine plan, subsidence repair procedures, a water replacement plan, and an intensive monitoring system. 29