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affected by Trapper mining because the mining extends only to the top of the drainage divide and not into the Horse Gulch drainage. Detailed discussions of selected groundwater quality constituents are presented in the Annual Hydrologic Reports (Appendix W). These discussions take into account all of the most recent data along with the historical information. Impacts to adjudicated wells (see Map M31) A discussion of groundwater inflow impacts to adjudicated wells can be found on pages 4-226a through 4-226d. One First White Sandstone well, W-1406-78, exists north of the Colt and Browning Pits. This well is approximately 3700 feet north of the edge of Browning Pit (Appendix V, Part D). The First White Sandstone crops out north of the northern end of the Browning pit. The southern limit of the First White Sandstone is approximately 1100 feet north of the northern end of Browning pit (Appendix V, Part D). 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 significant 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. This well was sealed and abandoned in 2006. No water quality impacts were ever noted at this site. Second White Sandstone well 85775-A exists west and north of the Colt and Browning pits. The Second White Sandstone aquifer exists only in the far northern portion of mining in the Browning and Colt pit areas. 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. The Second White Sandstone does not exist in the Derringer, Enfield, or Flintlock pits. The Second White Sandstone is probably not saturated in the area of the Ashmore pit in the Pyeatt or Flume Gulch drainages. Therefore, wells completed in this aquifer are not expected to be impacted by the Trapper Mine. Third White Sandstone wells 93848 and 031820 are documented to be located in the area of the Colt and Browning pits. Well 031820 does not still exist. Little if any effect at well 93848 is expected. The physical location of the well relative to the subsurface strike and dip of the coal seams in the Browning and Colt pits makes contact with any leachates virtually impossible. No Second or Third White Sandstone wells exist within one mile north of the permit boundary in the Pyeatt Gulch area. Significant drawdowns in the Third White Sandstone to the north of the mine are not expected because drainage of groundwater to the north end of the mine, due to the increase in permeability in the backfill aquifer, will likely moderate water level changes in the Third White Sandstone aquifer north of the mine. Significant natural water-level changes have been observed in the Third White Sandstone aquifer at wells GC-2, GP-9 and P-8 due to wet and dry cycles. These natural changes are likely to mask any water-level changes due to mining. The OR (92425, 89740) and KLM (88592, W606) wells in the eastern portion of the permit should not be impacted due to their distance from mining. Wells 226553F, 226554F and 22100F are completed below the Twentymile Sandstone and should not be impacted by Trapper mining operations. 4-238h