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- 30- 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 Urchard Valley Mine were initially dry, but after allowing these holes to recover some accumulated water, up to 300 gallons 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 ARCU on the Barren member of the i~1esaverde Formation in September, 1975. The preliminary transmissivity obtained for this member was calculated to be 2.46 g/d/ft. Also, ARCO performed a preliminary aquifer test on a fractured area in the "F" seam which yielded a transmissivity of 16.68 g/d/ft. 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 and Somerset Mines also indicate that the coal seams in the region are poor aquifers with very low transmissivities. The "B-2", "E" and "F" seams were observed to weep sliyhtly at fresh cut faces, while mine entry walls a short distance from the face were dry. The sandstone and siltstone roof strata in the 81ue Ribbon, Hawk's Nest and Somerset mines also weep for short periods of tune following mining and eventually dry up. The Hawk's Nest Mine workings in the "E" seam are dry even though these workings are within 600 feet of the North Fork, are below the level of the North Fork, and are parallel to the North Fork. These in-mine obervations indicate that the "B-2", "E" and "F" coal seams and their roof strata are not significant regional aquifers. Observations of mining within the "C" seam at the Bear No. 1 and No. 2 mines and of mining within the "D" seam at the Orchard Valley Mine indicate that the "C" and "D" seams and their asociated roof strata also are not significant regional aquifers. If the coals and their roof strata were aquifers, these strata would have continued to weep throughout the life of these mines.