2012-10-29_PERMIT FILE - M2012045 (6)

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EXHIBIT "G" 6.4.7 Water Information: (1) Impact to ground water: The proposed operation is a mining operation with developed water resource and other disturbed areas reclaimed as rangeland as the post mining land use. The operation will have some degree of impact to the ground water flow regime, but not to ground water quality or to unauthorized uses of ground water, i.e. water rights. The depth to ground water varies from approximately 7.5 feet on the south to approximately 30 feet deep on the north edge of the proposed permit boundary. According to the Design Report, Appendix IV, "The ground water is tributary to the Arkansas River and generally flows from west to east through the alluvium. Dewatering practices at the Freemont gravel mine may induce a local gradient to the southwest, but generally the ground water gradient at the Central Reservoir" (Phase One) "trends from the west - northwest to the east - southeast toward the Arkansas river." They go onto to state, "Upon completion of the reservoir, groundwater will most likely raise somewhat and mound on the west side of the reservoir and slurry wall. Additionally, a groundwater "shadow" may be created on the eastern side of the reservoir, where groundwater levels may drop below present levels." (2)(a) If the operation is expected to directly affect surface or ground water systems, then locate water structures facilities, etc. on Exhibit "C ": All such structures and facilities have been placed on Exhibit "C" to the best of the Operator /Applicant's knowledge. (b) Identify all known aquifers: The only known aquifer is the alluvial aquifer into which the Operation will mine. A portion of the proposed Operation will impact a Well Head Protection Area (Portions of Section 31 and all portions of the Operation is Section 6) as identified in the Colorado Department of Public Health and Environment (CDPHE) in the Avondale Wellhead Protection Plan. The impacted area is to the north and west of the Avondale well field and is separated from the well field by Chico Creek on the east and the Arkansas River on the south. It is unlikely that the proposed Operation will impact the quantity or quality of ground water flowing to the Avondale well field given the nature of the mining operation, the installation of slurry walls and zoned perimeter dam, and that Chico Creek borders the Operation on the east and the Arkansas River is south of the operation. Comments received from CDPHE by the Pueblo County Planning Department via e -mail on April 12, 2007 recommended that the "...following items be considered during your (The Pueblo County Planning Commission) review." 1. "That the location of Avondale's wells, and the delineated area of their water source, be included on the maps so that those who review it know its location." (Please see Appendix III) 2. "That the Stonewall Springs Quarry be required to have a detailed Spill Prevention and Response Plan." The Applicant/Operator has committed to such a plan. 3. "Best Management Practices to minimize the surface runoff of any potential contaminates should be included in a Stromwater Management Plan." The Applicant/Operator has committed to such a plan. A review of the domestic and irrigation well applications filed with the Office of the State Engineer (SEO) into this alluvial aquifer, generally states that water rights were filed on all unnamed aquifers. According to SEO records available to the Operator /Applicant, no wells were completed below the alluvial aquifer in or adjacent to the proposed Operation (According to SEO records, the maximum well depth is 59 feet.) Nor will any aquifers below the hard claystone bedrock be affected by the proposed mining or reclamation operations. (c) Provide a plan showing how water from de- watering operations or from runoff from disturbed areas, stockpiles, and operating surfaces will be managed to protect against pollution of surface and ground water, both during and after operations: The Operation will need to dewater the areas enclosed by the slurry walls so that the operation may be dry mined In addition, the Operation will obtain a discharge permit in order to construct the zoned perimeter dam. A