2014-01-24_PERMIT FILE - C2010089 (5)

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Mr. Wayne I. Schieldt Page 2 of 7 June 21, 2012 according to the standards of the Colorado Division of Reclamation Mining and Safety ( "DRMS "). According to the information provided, DRMS requires that a sediment control pond be built at each point where surface water leaves the mining permit boundary. These ponds capture and control the water for a specific period of time to allow the sediment to settle. Consumptive use of water at the NHM consists of evaporation, dust suppression, and indoor and outdoor water use at the mine offices. You indicated that there are currently eight sedimentation ponds that have depletions from evaporation. Mining at the NHM area will require construction of three additional ponds. Two of the ponds designated as Ponds 7 and 12 will expose groundwater. For the purpose of this SWSP, you have proposed to replace the net evaporation from the on- channel ponds and replace the gross evaporation from the off - channel ponds. The unit evaporation rate per acre for both the on- channel and off - channel ponds is outlined in the attached Tables 10 and 11. Computation of the unit evaporation rate under this SWSP was reduced during the ice covered period. You have assumed the ice covered period to occur during the months of January and December, based on the average temperatures of 26.3 °F for January and 28 °F for December; using the averages from the Norwood and Uravan weather stations. However, for the purpose of this SWSP, the Applicant shall replace the net/gross evaporation depletions from the exposed ground water surface area that may occur during the assumed ice covered period (the months of January and December) for any time that the ponds are not completely covered by ice. The surface area and the associated evaporation amounts for each of the ponds are identified in the attached Table 12. Table 12 also shows the drainage location for each pond so replacement can be made to the right drainage in the event of a senior call on those tributaries. Based on the movement of the mining area within the NHM, the maximum evaporation is estimated to occur between 2014 through 2018. Thus the maximum evaporation for this period is estimated at 39.64 acre - feetlyr. Dust suppression is the main industrial use of water at the mine which is considered 100% consumptive. Western Fuels indicated the dust suppression amount for future mining of NMH will most likely be similar to the amounts that have occurred since 1998. The attached Table 9 shows the minimum, maximum, and average monthly amounts of dust suppression from 1998 to 2008. The average dust suppression amount for this period is identified as 38.44 acre - feetlyr. The indoor and outdoor water needs for the office and maintenance facilities have been supplied by the Town of Nucla, however with the movement of the mining area to the NHNM area and the Cyprus Mine area, the indoor and outdoor water supply will be from a well or a series of wells that are identified in the water court application in case no. 2010CW208. You assumed that future potable water use from the wells will be the same as the potable water use provided by the Town of Nucla. Total potable water requirements at the NHM were estimated to be 0.61 acre -feet per year (0.40 acre -feet for indoor use and 0.21 acre -feet for irrigation use). The total potable consumptive use was estimated to be 0.22 acre -feet per year (0.06 acre -feet from indoor use and 0.17 acre -feet from irrigation use). The lagged effect of these wells is shown on the attached Table 13. The wells used for indoor and outdoor purposes will be pumping from the Brushy Basin Formation, which is below the coal seam. According to an analysis impacts report prepared by Mr. Christopher Sanchez of Bishop - Brogden Associates, Inc. ( "BBA "), the potential point of impact for the NHNM area will be Tuttle Draw, which is below the Holder and Charlie Rice Ditches, but above the R &H Development Ditch and for the Cyprus area, the lagged effect from well pumping would impact Calamity Draw above the Richards Waste Ditch. The Integrated Decision Support System Alluvial Water Accounting ( "IDS AWAS ") stream depletion model was used to determine the lagged depletions of these wells to Tuttle Draw and Calamity Draw. The aquifer characteristics used in the model for both the NHNM area and