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4.3.1. Impacts to Adjudicated Wells Isee Trapper Permit C-81-010 Mao M31) One First White Sandstone well, W-1406-78, exists north of the historic Colt and Browning Pits. This well is approximately 3700 feet north of the edge of Browning Pit (see Permit C-81-010 Appendix V, Part D). The First White Sandstone crops out north of the northem end of the Browning pit. The southern limit of the First White Sandstone is approximately 1700 feet north of the northern end of Browning pit. Impacts from mining would either have to be transmitted from the Second or Third White Sandstone through shales to the First White Sandstone aquifer, or through direct contact of surface impacted waters with the First White Sandstone aquifer. It is unlikely that an adequate vertical connection exists between the Second and/or Third White Sandstone, and the First White Sandstone, to result in negative impacts. A very limited potential exists for surface water runoff derived from spoil springs to contact the First White Sandstone although no sign cant spoil springs have yet been identified in this area. During 1988, First White Sandstone monitoring well, GLUX-1, was established to evaluate water quality in this aquifer downgradient of the Colt and Browning pit areas. Permit C-81-010 Map M52 depicts the actual location. No water quality impacts have been shown as this site. The GLUX-1 well will be abandoned following approval of this SL-7 document. Second White Sandstone well 85775-A exists west and north of the Colt and Browning pits. The Second White Sandstone aqu'rfer outcrops to the north of mining in the Browning and Colt pits area. Well 85775-A is located approximately two miles from this mining. A noticeable drawdown from the Browning pit mining did not develop at this well. Therefore, it is likely that the Trapper Mine does not impact this well. Third White Sandstone wells 93848 and 151991 are located 3,600 and 3,000 feet from the northern extent of historic Browning Pit mining. These wells will likely not be impacted by mining operations that occurred in Browning and Colt pits, ending in 1993. The strike and dip of the HI coal seams indicates that both wells are completed above the H coal seam. Therefore, it is likely that these wells will not have direct communication with ground water that flows through the backfill aquifer in the Browning and Colt pits. In the alternative, assuming good contact between the HI backfill area and wells 931)48 and 151991, estimated travel times of 20 and 16 years, respectively, were obtained. A gradient of 0.067 ft/ft was obtained for the 1996 HI aquifer water-level elevation map in this area and the use of an average permeability of 0.5 ft/day along with an effective porosity of 0.1, were used to obtain this travel time over the 3,600 and 3,000 foot distances, respectively. In the unlikely event that contact between these wells and the Browning and Colt Pit backfill aquifer should occur, water quality of the wells would not be degraded to the point it is no longer suitable for current uses.