2016-01-07_PERMIT FILE - C2010089A (11)

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installed by the permittee and domestic wells within the surrounding area are shown on Map 2.04.7-8. Analyses and programs integral to the Water Rights Plan are presented in several sections of the permit. A review of these sections is appropriate. Pit inflow volumes and pit pumpage drawdown projections are discussed and presented in Probable Hydrologic Consequences at the end of this section. Impacts of mining discharges on downstream water quality and the shallow ground water quality for water use considerations are also presented in Probable Hydrologic Consequences at the end of this section. Specific ground and surface water monitors for the purpose of verifying draw -downs and changes related to water rights in stream - flow volumes will be agreed to with DRMS. Finally, the detailed water rights plan which integrates the above -referenced information is presented in Appendix 2.05.6(3) -la. Water Rights Protection and Mitigation Plan The following discussion briefly summarizes the approach to the water rights plan. All ground and surface water rights within 1 mile radius of the New Horizon North Mine have been documented. Pit inflow and pit pumpage drawdown analyses were performed and tabulated. Drawdowns and pit bottom elevations were compared against water righted well production zone elevations to determine which wells could potentially be impacted by the mining induced drawdowns. Similarly, surface water rights within the one - foot drawdown contours were identified as those surface water rights which could potentially be impacted by the mining induced drawdowns. Drawdown depletion rates were then estimated at the different surface water right locations and replacement rates were determined for each. Calculations were performed to estimate industrial uses of surface water and evaporative losses from the sediment ponds receiving runoff from the mining areas. An augmentation plan was then developed for augmenting these surface water losses during each month of the irrigation period and storing water during the winter months, (see Table 12 in Appendix 2.05.6(3) -lb, WRS, LLC Report on Water Augmentation Plan). Calculations were performed for Tuttle, Coal Creek Canyon and the San Miguel River to determine if mine discharges would diminish receiving water quality to the extent that surface water rights would be injured. Table 2.05.6(3)-2 (presented in a succeeding discussion in this section) shows the results of the calculations which were conducted by weight averaging TDS content (by flow in cfs) of the mine discharges and the receiving waters. Presently, there are no surface water rights (or users) of the irrigation runoff water primarily because there is no practical way to divert the water in the stream bottoms by means of gravity flow to upland tillable areas in either Tuttle Draw or Coal Creek Canyon. The effect on the quality of San Miguel varies from about 5% TDS during low flow (irrigation season) to 0.4% TDS during periods of high flow (non -irrigation season). This was determined not to be a significant impact and no mitigation is required. Section 2.05.6(3) Page 8 Sept. 2015 (TR -11)