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When mining was in progress,water utilized for mine operations was obtained from a well <br /> in the Stevens Gulch Well Field. There has not been any detectable impact to the <br /> groundwater/surface water regime in this well field since pumping began at the site. <br /> Dewatering has occurred at the Bowie No. 1 Mine, but the extent is believed to be <br /> insignificant. Mine inflows may be derived from fractures associated with perched aquifers <br /> within the overlying Mesaverde, surficial alluvial/colluvial sediments, and stream flows <br /> associated with fracture systems, as well as from dewatering of the coal aquifer itself. In <br /> 1983, approximately 300,000 gallons of water flowed into the mine from perched, <br /> discontinuous, water bearing sandstones overlying the D seam. A Division inspection in <br /> March 1986 documented inflows of 200 gallons per day. This inflow gradually slowed <br /> once this perched aquifer was completely dewatered.Inflows during 1991 failed to produce <br /> over 3 gpm for any significant period of time. Because the portals at the Bowie No. I Mine <br /> were sealed in 2001 and the West Mine portals were sealed in 2000, there is no current <br /> information on mine inflows. <br /> BRL established an extensive monitoring system to monitor water levels in <br /> colluvial/alluvial deposits in the permit area and in the alluvium of streams overlying mine <br /> entries. No significant water level fluctuations were noted in conjunction with mine <br /> inflows. Mine inflows in the mains underlying East Roatcap Creek averaged less than 1 <br /> gpm from 1987 to 1993. <br /> The coal aquifer has been studied extensively, and this insignificant aquifer has yet to make <br /> a visible contribution to mine inflows. <br /> Surface Water <br /> The Bowie No. I Mine area will not significantly affect the local surface water hydrology <br /> or the regional hydrology. Sediment control measures will ensure protection to stream <br /> quality. No mine water will discharge from the portals and no water will be withdrawn <br /> from the creek. Clean water diversions above the main facilities minimize surface water <br /> runoff through the site. Mine inflows under and adjacent to the creek are predicted to be <br /> insignificant. Discussions of sediment control measures, subsidence impact mitigation, <br /> water augmentation plans, and surface water inflow predictions follow. <br /> Disturbed area drainage from the West Mine, ROM, East Mine, and loadout area were <br /> collected and treated at each site. Four sediment ponds collected disturbed area drainage <br /> from the mine benches. Another pond controlled sediment generated by the underground <br /> development waste pile. One pond controlled drainage from the ROM stockpile area. Two <br /> ponds collect drainage from the disturbed areas of the loadout, truck scales, and highway <br /> coal stockpile area. The mine operator has applied for and/or obtained the appropriate <br /> NPDES permits. Effluent quality from the remaining sedimentation ponds is monitored to <br /> determine permit compliance. <br /> 26 <br />