2008-09-05_PERMIT FILE - C1981012A (2)

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feet (the elevation of the bottom of the airshaft and slope entries) allowing entry into and • exploration of the mine. Initial pumping capacity is planned at 4,000 gpm. Location of the pumping system is shown on Map 11 -Surface Facilities and Roads East Portal. At this rate dewatering may take from 6-9 months dependent on actual quantities of water encountered. After dewatering to 7162' elevation, pumping will continue to occur from pumps located underground and the temporary system will be removed. Prior to mine closure, mine water quality allowed discharge directly into the Purgatoire River with no treatment. Since closure, mine water samples have been periodically extracted from the East Portal airshaft and a borehole into the mine workings (NEW-2 and NEW-4 of the hydrologic monitoring plan). Sample results collected at these sites indicate that direct discharge can be resumed in compliance with NPDES permit limitations. Additional samples will be collected at the pumphead and analyzed for the parameters listed in the NPDES permit renewal application, page 10 items 26 and 28 (Exhibit 22 of the New Eik permit). No discharge to the Purgatoire River will occur until confirmation of satisfactory test results. NECC has submitted an application to modify the NPDES permit to allow diverting the mine water though a treatment pond prior to discharge into the Purgatoire River. Pond 001 will be constructed for this purpose. Figure 5 provides design criteria and proposed cross-sections for pond 001. The location of pond 001 is shown on Map 13 Sediment • and Surface Water Control Plan -East Portal. Coal processing waste (from sediment pond clean-0ut) and remnant coal stockpile debris will be removed from the pond site and disposed of at the Development Waste Pile prior to pond construction. This material will not be used in pond embankment construction. Pond 001 will continue to receive mine water once mining operafions are resumed. Future water production is expected to range from 125 to 300 gpm, but is dependent on mine production and conditions encountered. Mine water will be retained in the pond only as necessary for compliance with NPDES permit limitations. Any excess pond capacity may be used for water storage to supplement mining and preparation plant operations only to the extent allowed by water rights leased by NECC. (5) T~soil A majority of the disturbance at the New Elk Mine occurred prior to existing regulations on salvaging topsoil. As such, only a limited amount is available for reclamation. The exception to this is the refuse TR-49 2.05-19 (Revised 02-15-07)