2014-12-15_PERMIT FILE - M2014043

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WATER INFORMATION EXHIBIT G (cont) walls will be certified to permanently address evaporation losses if the lined area were not backfilled. The landowners have adequate water available to supply initial makeup water. Their 3 water wells are shown on the PRE-MINING PLAN MAP-EXHIBIT C. TABLE G-WATER WELLS WITHIN 600 was prepared from printouts obtained at the State Engineers office. It lists the wells within 600 feet of the mined area. One well is still listed under DOW name but has no location data. A map showing the Well locations according to the Office of the State Engineer data is also provided labeled MAP EXHIBIT G -WELL MAP. There appears to be 3 water wells on the site, that have been used by the landowners for domestic and agricultural uses . There are 5 monitoring wells owned by Thornton that have been used to monitor groundwater levels associated with their water storage reservoir to the west and 3 monitoring wells on the property to the north. The 4 remaining wells are located outside the mine area and include 2 domestic and 2 irrigation wells. These wells will not be impacted by the mining operation since no dewatering is planned until the slurry walls have been installed. We estimate dust control for the various parts of the operation, i .e. roads, crushing, washing, etc. to be a maximum of 8 ac-ft per year. This water will be obtained from a source approved for that use. No water will be used for reclamation, nor will the revegetated areas be irrigated by the operator. The well permit and Temporary Substitute Supply Plan will explain where Albert Frei & Sons, Inc. , will obtain the water needed by this mine. THE APPENDIX CONTAINS A GROUNDWATER MONITORING PLAN THAT ADDRESSES THE POTENTIAL OFFSITE IMPACTS DUE TO THE PROPOSED SLURRY WALLS . TO THE NORTH IS AN OLD GRAVEL MINE THAT WAS BACKFILLED BY PAT BRODA. THIS MAY HAVE PLACED AN IMPEDIMENT TO GROUNDWATER FLOW ACROSS THAT SITE , THAT MOUNDS GROUNDWATER ON THIS SITE. SINCE THE AREA TO THE NORTH IS FILLED NOW , OUR FILLING ACTIVITIES WILL NOT INCREASE THE SHADOWING ALREADY TAKING PLACE TO THE AREA NORTH OF PHASE 2 . WE DO NOT BELIEVE THERE WILL BE A DOWN GRADIENT PROBLEM ON THE WEST SIDE SINCE THE ENTIRE WESTERN PART OF THE PROPERTY LIES ADJACENT TO A SLURRY DAM OWNED BY THE CITY OF THORNTON THAT MAY BE IMPEDING WATER FLOW OFF THIS SITE . IN ADDITION, THE BULL SEEP FLOWS ALONG THE ENTIRE WEST SIDE OF THE SITE AND ACTS AS A RECHARGE FOR DOWN GRADIENT PROPERTIES .