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There are no users or beneficial uses for the relatively small amount of ground <br />water that is currently moving through the bedrock zones toward the cropline <br />to the southwest. Recharge from irrigation (the major source of recharge) will <br />continue to the east, north and west of the NHN permit area as it currently <br />does. Irrigation water that now infiltrates into the bedrock zones at NHN will <br />be diverted around the mining area in a HDPE pipeline. Seepage out of the <br />northward advancing high-wall will be diminished from what is currently <br />being experienced from the old Peabody high-wall because the annual recharge <br />from irrigation water flowing across the permit area will be eliminated. Based <br />on WFC’s estimated maximum pit inflow rate, the extent of the 1 foot <br />drawdown contour is projected to be about 760 feet from any point in the pit. <br />This would result in a short term impact of minimal significance. Wells <br />proximate to mining areas are completed in deeper units and are not likely to <br />be injured. WFC will monitor the bedrock zones and pit discharge in order to <br />refine the extent of drawdown. The hydrological monitoring program should <br />provide reasonably accurate measurements of the effects of mining. While <br />there are no known uses for the shallow bedrock zone water, WFC (as <br />described in the water augmentation plan), has a 114 acre foot consumptive use <br />right on the Colorado Cooperative Company ditch which could be used to <br />mitigate any potential impact on groundwater or surface water right users from <br />pit inflow drawdown. <br /> <br />2) Impact on groundwater rights. There are no existing groundwater rights within <br />the permit area or within a 1 mile radius. The only well with an adjudicated <br />water right was the Peabody Coal Company Nucla Mine Shop Well. <br />According to WFC this well has been abandoned. There are no ponds that <br />would be removed by mining. Two permitted wells (Well Permits <br />#253229/Meehan Well and #163178/Glassier Land) will be mined through. <br />The Meehan Well is under an option to purchase and the Glassier Land is <br />under lease. Both of these wells are Morrison Formation completions and will <br />be plugged appropriately prior to mining. No impacts are expected to any <br />known groundwater rights. <br /> <br />3) Impact of spoil material on groundwater flow and recharge. Following mining <br />the water level in the Dakota Formation bedrock zones immediately adjacent to <br />the mined out area will experience decline. The water levels are expected to <br />recover as indicated by data from at least one well at the adjacent New Horizon <br />Mine. Monitor hole GW-N8 (see Figure 2.05.6(3)-2a, Appendix 2.05.6(3)-2) <br />experienced a water level decline of about 12.2 ft. in the overburden and coal <br />zone in response to the mining at the old Peabody Nucla Mine. Following <br />backfill and reclamation of the old Peabody highwall (in early 1992), the <br />bedrock zone (OB and Coal) water level at GW-N8 has recovered about 10 ft <br />or 80% of its decline in a period of less than 20 years. The impact of the <br />backfill material on the localized groundwater flow and recharge is not <br />considered significant. The groundwater from the Dakota bedrock zones has <br />not been used to date because of poor quality and low production potential. <br /> <br /> <br /> <br />27 <br /> <br />