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within the Blue Ribbon Mine since the mine workings are all topographically above the Rollins Sandstone. The Biue Ribbon Mine may affect the quantity of ground water in strata which overlies the mine workings. Only minor discontinuous lenticular and interbedded sandstones have been identified through drilling above the permit and adjacent areas. Most of these sandstones are dry, while others support localized perched aquifers. These strata may be dewatered into the mine 1) through faults and fractures, and/or 2) through conduits created by subsidence. Fractured roof conditions have produced mine inflows at the Blue Ribbon Mine. To date, these inflows have been few, have been short in duration and have involved relatively minor amounts of water. The characteristics of these inflows indicate that the source of water has a limited recharge area and has a limited storage capacity (i.e., limited thickness and areal extent). The water flowing from these fractures most likely originates from overlying perched aquifers in lenticular sandstones and from the fractures themselves. The pulling of coal pillars within the mine may produce subsidence. The subsidence may impact the overlying water-bearing strata with the Mesaverde Formation. However, no overlying strata are used for water supplies and no significant spring flows to date have been observed emanating from these strata. The potential future use of the lenticular sandstones for water supplies is limited by: 1) the steepness of the stream valley slopes, 2) the depth of drilling, 3) the low well yields which are expected from the tight, fine-grained sandstones, and 4) the limited recharge areas of lenticular sandstones. The Blue Ribbon Mine will not affect the quality of water in the overlying strata. The E coal seam is not an aquifer. The mine workings are dry, except in a few areas of fracturing. Impacts from Coal Mine Waste Disposal on Ground Water During 1984 and 1985, the mine bench at the Blue Ribbon Mine was stabilized by rebuilding the mine bench with an engineered fill of underground coal mine waste. This material was obtained from Mountain Coal Company's West Elk Mine. Rock underdrains were placed in and under the coal mine waste to channel spring water and seepage from the coal mine waste fill. During 1986, it is estimated that the underdrains discharged 1.37 acre-feet. In subsequent years, the flow has generally decreased. During 1991, the underdrains discharged 0.035 acre-feet. The conductivity of the discharge from the north -25