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-25- <br />Stevens Gulch. Pumping tests conducted by Colorado Westmoreland <br />Incorporated at the Orchard Valley Mine indicate that the Stevens Gulch <br />alluvium could support a pumping rate of 28 gpm. The .Bear Mine and <br />Terror Creek Loadout use some water drawn from wells completed in the <br />alluvium along the North Fork of the Gunnison River. <br />Water quality analysis for the Stevens Gulch well water indicates good <br />quality water,.with none of the parameters exceeding the recommended <br />drinking water standards. <br />The water quality for the Hubbard Creek well water is fair to poor and <br />contains total dissolved solids and sodium levels which at times exceed <br />secondary mater quality standards for drinking water. <br />Occurrences of ground water have been noted in the Mesa Verde Formation <br />from information obtained from drilling, experience in the mines, and <br />from the presence of springs and seeps in the region. This information <br />also indicates that the only potential regional bedrock aquifer in the <br />general area is the laterally continuous Rollins sandstone. The <br />laterally discontinuous lenticular sandstones within the Upper Mesa <br />Verde Formation support only localized ground water flows. <br />Recharge to the Rollins sandstone occurs along outcrops, along subcrops <br />beneath stream alluvium and in the channels of the North Fork and its <br />tributaries. However, due to the steepness of the topography in the <br />outcrop areas (i.e, sandstones are cliff formers) and the narrowness of <br />the stream valleys, the Rollins sandstone receives little recharge, <br />except in the area under the North Fork of the Gunnison River and its <br />associated alluvial deposits. <br />Some recharge to the Rollins sandstone may come indirectly from the <br />percolation of snowmelt and precipitation downward through faults and <br />fractures. Drill holes which penetrated the Rollins sandstone near the <br />Orchard Valley Mine were initially dry, but after allowing these holes <br />to recover some water accumulated, up to 300 gallons, in the casing. <br />However, this amount of water is insufficient to provide a desirable <br />well yield. This indicates that recharge along outcrops and subcrops <br />above the level of the North Fork is insufficient to sustain ground <br />water wells developed in the Rollins. The only domestic use of the <br />water from-the Rollins sandstone is from wells along the North Fork <br />near the Hawk's Nest Mines. The water quality elsewhere is considered <br />too saline for domestic use (Prince and Arrow, 1974). <br />Preliminary aquifer tests were performed by WECC on the Barren member <br />of the Mesa Verde Formation in September, 1975. The preliminary <br />transmissivity obtained for this member was calculated to be 2.46 <br />g/d/ft. Also, WECC performed a preliminary aquifer test on a fractured <br />area in the "F" seam which yielded a transmissivity of 16.68 g/d/ft. <br />Another "F" seam well completed in an unfractured area in the coal seam <br />was dry. These aquifer tests indicate that the "F" seam and the <br />lenticular sandstones of the Barren member are poor aquifers at best, <br />as ground water flow is mainly concentrated in fractured rock. <br />~- <br />_.. _ .. <br />.. <br /> <br />