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1. There are six sediment ponds at the West Elk Mine that treat drainage from the <br /> disturbed area. These ponds function as designed to ensure compliance with <br /> the water quality standards and effluent standards specified in CDPS Permit <br /> No. CO-0038776. <br /> 2. Underground mine water has been pumped to the ground surface, passed <br /> through a polishing pond, and then discharged into Sylvester Gulch at CDPS <br /> outfall 017. As of October 8, 2008, Colorado Water Quality Control Division <br /> is reviewing past exceedances of discharge limitations for iron(potentially <br /> dissolved and total recoverable) at outfall 017. MCC has ceased mine water <br /> pumping at Outfall 017 and is investigating potential corrective measures to <br /> ensure future discharges at Outfall 017 comply with effluent limitations <br /> specified in CDPS Permit No. CO-0038776. <br /> 3. The Division proposes to exempt specific small areas from the use of sediment <br /> ponds for the following reasons: each area is of limited size, ponds and <br /> treatment facilities are not necessary for drainage in each area to meet the <br /> effluent limitations of Rule 4.05.2 and applicable State and Federal water <br /> quality standards for receiving streams, and no mixing of surface drainage with <br /> a discharge from underground workings will occur. The following areas are <br /> exempted: the Sylvester Gulch fan site, an area located downstream from the <br /> MB-5E pond, the 1.2 million gallon water tank, the area surrounding the raw <br /> water intake gallery, the Shaft 3 area,the drill pads utilized at the "thermal <br /> event" area, the drill pads at MVBs, the sites of the former Lone Pine <br /> substation and Lone Pine ventilation fan and associated facilities, the corrals <br /> laydown/staging area, and the Deer Creek Shaft area [4.05.2(3)(b)(i)]. <br /> B. Diversions and Conveyance of Overland Flow <br /> 1. Sediment control ditches have been designed and constructed in compliance <br /> with Rule 4.05.3. Locations are shown on the Map 54 series, and designs can <br /> be found in Exhibit 66. A summary of the designs can be found on Table 44 <br /> in Exhibit 66 of the PAP [4.05.3(2)]. <br /> C. Stream Channel Diversions <br /> 1. The West Elk Mine does not propose any stream channel diversions; <br /> therefore,this section is not applicable. <br /> D. Sedimentation Ponds <br /> 1. Mountain Coal Company has constructed six sediment ponds and two <br /> freshwater ponds. The ponds have been designed, constructed and maintained <br /> in accordance with the requirements of 4.05.6 and 4.05.9. The location of <br /> these ponds can be found on the Map 54 series. The designs of the ponds can <br /> be found in Exhibit 66. The ponds are located as near as practical to the <br /> disturbed area and are not located within perennial streams according to <br /> 4.05.6(1)(b). <br /> 34 <br />