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wells, etc. completed in aquifers will be accomplished using cement or other suitable sealant. The sealant <br />will be placed in the hole from the bottom to within ten feet of the surface. Surface plugs used to <br />complete the permanent sealing of holes, wells, etc. will be selected and used only if the CDRMS gives <br />prior approval. All associated surface sites will be reclaimed following the cessation of mining. SP will <br />submit to the CDRMS a proof of compliance report containing pertinent information on permanent <br />sealing of any hole, well, etc. within 60 days of completion of such activities. <br />Ground Water Quantity The backfilling and grading of spoil materials is accomplished with dozers and <br />scrapers (see Tab 20, Backfilling and Grading). Procedures outlined in Tab 20 will assure the eventual <br />re -saturation of the disturbed areas (pits) by creating greater porosities and hydraulic conductivities due to <br />the characteristics of the excavated materials and material swell. In addition to the backfilling methods, <br />topsoiling and revegetation plans outlined in Tabs 21(Minesoil Reconstruction), and 22 (Revegetation <br />Plan), will enhance the potential for establishing reclaimed areas that exhibit similar or greater infiltration <br />rates and recharge capacities than premining conditions. Reseeding and mulching of redistributed topsoil <br />will augment moisture retention and infiltration rates of the reclaimed areas. Mechanical manipulation of <br />the regraded spoil and topsoil in areas that become compacted during mining (disking with an offset disk <br />or deep ripping) will further aid the infiltration and percolation of moisture into the root zone and <br />downward into the water table. <br />Excess ground water inflow to the pits will be removed by pumping the water into sediment ponds. <br />Design criteria for each sediment pond (both existing and proposed), is presented in Tab 13 (Facilities). <br />Each pond is designed to contain and treat runoff from a 10 -year, 24-hour storm event plus additional <br />storage capacity for water pumped from mine pits. <br />Surface Water Quality Design criteria for each sediment pond is outlined in Tab 13 (Facilities). Each of <br />the sediment ponds is designed to prevent additional contributions of sediment to stream -flow outside the <br />permit area and incorporates detention times sufficient to assure that all applicable effluent standards will <br />be met. Ponds 005, 006, 009, 015, 016, and 017 have been approved for retention as permanent <br />impoundments to support the approved postmining land use. Other ponds will be reviewed prior to final <br />bond release, and will either be removed and reclaimed, or a revision(s) will be submitted requesting <br />approval of retention as permanent impoundments. <br />SP incorporated sediment ponds 015, 016, and 017 in the Dry Creek and Sage Creek drainages in a <br />renewal application for the existing NPDES Permit (CO -0000221). All terms and agreements specified in <br />the permit will be adhered to during the mining operation. It is not anticipated that treatment of pond <br />discharges will be required to meet applicable effluent standards. <br />RN06 2 12/05/16 <br />