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<br />Derr Pit Project <br />DRMS 112 Permit <br />Temporary Stockpile Seed Application Rate * <br />(#PLS/acre) % in mix <br />Slender wheatgrass 2.8 #PLS/ac 25 <br />Smooth bromegrass 3.9 #PLS/ac 30 <br />Pubescent wheatgrass 4.2 #PLS/ac 30 <br />Sand dropseed 0.03 #PLS/ac 5 <br />Crested wheatgrass 0.6 #PLS/ac 10 <br />Totals 11.53 #PLS/ac 100 <br />* Application rate is for drilling the seed. If seed is to be broadcast, the application <br />rate will be doubled. <br />The seed mix for final reclamation as described above does not require fertilizer as <br />recommended by the local NRCS office in Greeley, Colorado <br /> <br />Water – General Requirement <br /> <br />To minimize the effect on the prevailing hydrologic balance, the operator shall: <br />a. Comply with all applicable Colorado water laws. <br />b. Comply with all applicable Federal and State water quality laws and regulations. <br />c. Comply with all Federal and State requirements for dredge and fill. <br />d. Re-grade and backfill all sediment and siltation structures after mining is <br />completed. <br /> <br />Groundwater – Specific Requirements <br /> <br />The operation will not affect groundwater quality on or off the site. The operation will <br />comply with State groundwater quality standards. Due to the absence of sources of <br />potential pollutants, groundwater quality monitoring is not required in this operation. <br /> <br />The mining and reclamation will affect the groundwater table surrounding the mine site. <br />Proposed mitigation efforts to minimize these impacts are a recharge pond along the <br />southeast corner of the property to maintain groundwater levels during the mining, and <br />a perimeter drain if needed to convey groundwater around the lined reservoir after the <br />slurry wall is installed. <br /> <br />The depth to groundwater has been measured on a monthly basis in piezometers <br />located on the interior and exterior of the proposed slurry wall alignment since October <br />2006. Groundwater depths will continue to be measured and recorded at monthly <br />intervals in each piezometer to establish what the seasonal groundwater levels are. <br />These measurements will be used as a benchmark for maintaining the groundwater <br />levels in subsequent years. The triggers that would require the perimeter drain to be <br />installed are as follows: <br />