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-23- Water quality analysis for the Steven's Gulch well water indicates good quality water, with none of the parameters exceeding the recommended drinking water standards. The water quality for the Hubbard Creek well water is fair to poor and contains total dissolved solids and sodium levels which exceed secondary water quality standards for drinking water. Occurrences of ground water have been noted in the Mesaverde Formation from information obtained from drilling, experience in the mines, and from the presence of springs and seeps in the region. This information also indicates that the only potential regional bedrock aquifer in the general area is the laterally continuous Rollins sandstone. The laterally discontinuous lenticular sandstones within the Upper Mesaverde Formation support only localized ground water flows, and are considered to be insignificant in terms of the overall hydrologic balance. Recharge to the Rollins sandstone occurs along outcrops, along subcrops beneath stream alluvium and in the channels of the North Fork and its tributaries. However, due to the steepness of the topography in the outcrop areas (i. e, sandstones are cliff formers) and the narrowness of the stream valleys, the Rollins sandstone receives little recharge, except in the area under the North Fork of the Gunnison River and its associated alluvial deposits. Some recharge to the Rollins sandstone may come indirectly from the percolation of snowmelt and precipitation downward through faults and fractures. Drill holes which penetrated the Rollins sandstone near the Orchard Valley Mine were initially dry, but after allowing these holes to recover, some accumulated up to 300 gallons of water in the casing. However, this amount of water is insufficient to provide a desirable well yield. This indicates that recharge along outcrops and subcrops above the level of the North Fork is insufficient to sustain ground water wells developed in the Rollins. The only domestic use of the water from the Rollins sandstone is from wells along the North Fork near the Hawk's Nest Mines. The water quality elsewhere is considered too saline for domestic use (Prince and Arnow, 1974). Preliminary aquifer tests were performed by WECC on the Barren member of the Mesaverde Formation in September, 1975. The preliminary transmissivity obtained for this member was calculated to be 2.46 g/d/ft. Also, WECC performed a preliminary aquifer test on a fractured area in the "F" seam which yielded a transmissivity of 16.68 g/d/f t. Another "F" seam well completed in an unfractured area in the coal seam was dry. These aquifer tests indicate that the "F" seam and the lenticular sandstones of the Barren member are poor aquifers at best, as ground water flow is mainly concentrated in fractured rock. Observations made underground by the staff of the Division at the Blue Ribbon, Hawk's Nest, Mt. Gunnison, Somerset and Orchard Valley Mines also indicate that the coal seams in the region are Poor aquifers with very low transmissivities. The "B-2'i, "E" and 'F" seams were observed to weep slightly