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-za- <br />Water quality analysis for the Stevens Gulch well water indicates good quality <br />water, with none of the parameters exceeding the recommended drinking water <br />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 water quality standards for drinking water. <br />Occurrences of ground water have been noted in the Mesa Verde Formation from <br />information obtained from drilling, experience in the mines, and from the <br />presence of springs and seeps in the region. This information also indicates <br />that the only potential regional bedrock aquifer in the general area is the <br />laterally continuous Rollins sandstone. The laterally discontinuous <br />lenticular sandstones within the upper part of the Mesa Verde Formation <br />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 outcrop <br />areas (i.e, sandstones are cliff formers) and the narrowness of the stream <br />valleys, the Rollins sandstone receives little recharge, except in the area <br />under the North Fork of the Gunnison River and its associated alluvial <br />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 to <br />recover some water accumulated, up to 300 gallons, in the casing. However, <br />this amount of water is insufficient to provide a desirable well yield. This <br />indicates that recharge along outcrops and subcrops above the level of the <br />North Fork is insufficient to sustain ground water wells developed in the <br />Rollins Sandstone. The only domestic use of the water from the Rollins <br />sandstone is from wells along the North Fork near the Hawk's Nest Mines. The <br />water quality elsewhere is considered too saline for domestic use (Prince and <br />Arrow, 1974). <br />Preliminary aquifer tests were performed by WECC on the Barren member of the <br />Mesa Verde Formation in September, 1975. The preliminary transmissivity <br />obtained for this member was calculated to be 2.46 g/d/ft. Also, WECC <br />performed a preliminary aquifer test on a fractured area in the "F" seam which <br />yielded a transmissivity of 16.68 g/d/ft. Another "F" seam well completed in <br />an unfractured area in the coal seam was dry. These aquifer tests indicate <br />that the "F" seam and the lenticular sandstones of the Barren member are poor <br />aquifers at best, as ground water flow is mainly concentrated in fractured <br />rock. <br />Observations made underground by the staff of the Division at the Blue Ribbon, <br />Hawk's Nest, Mt. Gunnison and Somerset Mines also indicate that the coal seams <br />in the region are poor aquifers at best with very low transmissivities. The <br />"B-2", "E" and "F" seams were observed to weep slightly at fresh cut faces, <br />while mine entry walls a short distance from the face were dry. The sandstone <br />