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2.oa.s(1) • GROUND WATER QUANTITY A review of the State Engineers records,(Figure 2.04.5-1), indicates that of the wells in the Red Canyon 111 Mine and proposed b2 Mine area, the largest yields are 15 to 20 gallons per minute and are "domestic use only" designation wells. Although no drillers logs are available, it appears that the majority of these wells are producing water from the glacial alluvial cover and not from the bedrock aquifers. The glacial outwash alluvial aquifer is fully saturated in most areas and is recharged by perennial, spring feed streams such as Williams Creek, Cottonwood Creek, and Ward Creek to the south. Since the aquifer is up to 250 feet thick in places and composed of loose gravel and boulder material, it is possible, although not demonstrated, that this aquifer could yield as much as 100 + gallons per minute to a properly developed well. Quantitatively, the bedrock aquifers are much lower in potential • yield. The coal beds are relatively thin, (generally less than ten feet), and rely on secondary fracture porosity to transmit water. It is estimated that these aquifers have permeability on the order of 100 times less than the overlying alluvial glacial outwash materials. Production to a well would-alsobe dependent on the extent of which the well penetrated the more highly fractured zones within the coal bed. The estimated production rate of any well penetrating one or more coal seams would be less than ten gallons per minute. With the exception of the Rollins Sandstone, the sandstone bedrock aquifers are usually thin, (less than 20 feet), very fined grained, highly cemented, and generally unfractured,except where regional joint patterns exist. These sandstones were deposited in lenticular, delta-like bar and lagoon sands are not laterally extensive. The hydraulic potential of these sandstones is limited and does not permit large capacity wells to be predicated or developed in these units. The P,olLins sandstone is the exception and, although it is usually 100 or more feet thick and is very extensive laterally, yields from a well in the Rollins Sandstone