2014-05-12_PERMIT FILE - C2010089 (5)

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Well Permit # Distance, Ft. 11801 2754 116113 2530 179418 3970 83553 4365 74597 4098 253099 4350 BBA's work shows that the closest permitted well ( #116113) would be expected to see a drawdown after 20 years of 0.62ft. Much farther away, permitted well ( #83553) would be expected to see a drawdown of 0.53 ft after 20 years of pumping. BBA reports that these levels of drawdowns are insignificant and represent less than 1% of the available drawdown. None of the permitted wells are located within 600 ft. of PW -001 and no waiver of the 600 ft. statutory limit would be necessary from the State Engineer's office. BBA's report is contained in its entirety in Appendix 2.05.6(3) -la. 3) Impact of Spoil Material on Groundwater Flow and Recharge. The mine pit floor will remain open only until the coal has been removed. The pit width will be about 110 ft wide as it is at the adjacent New Horizon Mine. At NHN, each pit advance will take about 2 months so the pit floor is only exposed for a few weeks at a time at most. Water levels in the bed rock zones (overburden, coal, and underburden) will decline in response to the pit face advancement to the north. The bedrock strata will be exposed along 3 sides. The pit side walls will be covered in a relatively short period of time by the advancing backfill and reclamation. Irrigation of the areas to the east, north and west of the permit area will continue unabated throughout the mine life and thereafter and' will continue to recharge the bedrock zones in those areas. Monitor hole GW -N8 (see Figure 2.05.6(3) -2a, Appendix 2.05.6(3) -2) experienced a water level decline of about 12.2 ft. in the overburden and coal zone in response to the mining at the old Peabody Nucla Mine. Following backfill and reclamation of the old Peabody highwall (in early 1992), the bedrock zone (OB and Coal) water level at GW -N8 has recovered about 10 ft or 80% of its decline in a period of less than 20 years. This indicates, that following mining the water level in the bedrock zones immediately adjacent to the mined out area that experienced decline will recover. Within the permit area, and south of Meehan Draw (see Map 2.04.7 -1), the structural attitude at NHN (see Map 2.04.7 -2) is such that irrigation and precipitation water percolating through the reclaimed backfill material will drain to the south along the path of least resistance and issue as spring(s) tributary to Tuttle Draw. To the north of Meehan Draw, any water percolating through the backfill could pond against the "low- wall" and eventually saturate the backfill and issue as springs tributary to Meehan Draw just as the irrigation return water now does. The reclamation plan, (area north of Meehan Draw), is dry land pasture with no irrigation. Figure 2.05.6(3) -1 is a generalized north -south cross - section showing the down gradient drainage through the NHN Mine backfill material. The backfill overburden material at NHN Mine will be placed in the mine pit areas using 3 techniques: 1) cast blasting, 2) end dumping of trucks from Section 2.05.6(3) Page 15 November 2011