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-16- Faults which cut through the mine pits may, however, transmit small quantities of water from the Upper Sandstone member to the mine pits. This has occurred in Wyoming Fuel's Pit 1, and is expected to occur in Pit 2. 4(yoming Fuel has estimated inflows in Pit 2 to be between 0 and 10 gpm. No wells have been completed into the Upper Shale member of the Pierre Shale to date due to its salinity and the low yields. No seeps or springs eminate from the Pierre Shale within the general area. Ground water occurs in both the Sudduth coal seam and the lenticular sandstones of the Coalmont Formation. Wyoming Fuel has conducted two aquifer tests (slug tests) on two different monitoring wells, lA and 5C, completed in the Sudduth coal seam. The aquifer test conducted by and for Wyoming Fuel indicates that the Sudduth coal is a poor aquifer, except in areas of faulting where there is an increased secondary permeability. The Sudduth coal seam is the only rock strata within the lower Coalmont Formation with a large enough areal extent to be considered a regional aquifer. Flow within this aquifer is controlled by the dip of the coal bed. Regional flow within the coal is downdip to the axis of the Bourg Syncline and the Johnny Moore Syncline, and then down the plunge of the synclinal axes. The coal seam is overlain and underlain by confining silts tone and shale strata which act as aquitards and aquicludes. The confining layers restrict the coal recharge zone to a narrow outcrop and subcrop band and also produces the artesian conditions observed in monitoring wells. No permitted water wells are completed within the Sudduth coal seam. The lower Coalmont Formation which overlies the Sudduth coal consists of interbedded and lenticular calcareous sandstones and siltstones. Ground water within this stratum is localized in the lenticular sandstones. The siltstones which intertongue with the lenticular sandstones act as aquitards which restrict the vertical and horizontal movement of ground water to and from these sandstones. Wyoming Fuel has conducted both laboratory permeability tests on core samples and slug aquifer tests on monitoring holes completed in the lower Coal Formation. The laboratory tests indicate that both the sandstones and siltstones have very low permeabilities, 0.05 and 0.02 millidarcies, respectively. Slug tests conducted by Wyoming Fuel at well sites 1B and 5C yielded higher permeabilities, 1.09 millidarcies, or 0.02 gpd/f t2 for 1B and 0.01 gpd/f t2 for 5C. The higher permeabilities measured in the aquifer tests were attributed to the higher secondary (fracture) porosities within the bore hole. Higher permeabiliLles were measured for this strata in pumping tests conducted by Kerr Coal Company and the U.S.G.S. (0.37 to 7.5 gpd/ft , respectively). Kerr also noted that fractures greatly increase the aquifer's permeability and that the sandstones, in the absence of fractures, have low permeabilities. The only permitted water well in the area is completed in a 26 foot lenticular sandstone of the Coalmont Formation, This water well is located in section 35, T9N, R78W and is owned by the Kerr Coal Company. This sandstone tapped by the Kerr well is strati graphically higher than the strata which will be disturbed during mining at the Kerr, Wyoming Fuel, and Bourg mines.