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ii. Mitigation of Groundwater Impacts - <br />The applicant anticipates no degradation of groundwater quality <br />during mining. The applicant will treat any mine water effluent <br />as necessary to meet water quality standards prior to discharge <br />and there will be no uncontrolled mine water discharge after <br />mining is complete which might otherwise degrade surface <br />streams or groundwater. The operation plan indicates most <br />water used for dust control will be absorbed on the coal and <br />carried from the mine, thereby minimizing the quantity to be <br />treated. Any discharge will be delivered and treated in the <br />sedimentation ponds and discharged as specified in the NPDES <br />permit. <br />To monitor the changes in water quantity and quality, the West <br />Elk Mine has an extensive ongoing Hydrologic Monitoring <br />Plan. Eighteen wells are currently being monitored in the <br />alluvium, the Barren Member, the F Seam, the B Seam and E <br />Seam. Two wells were been added to the monitoring program <br />in Jumbo Mountain but monitoring has since been discontinued. <br />A nineteenth well will be added in the B-seam down-gradient of <br />any mine water sumps developed in as part of the Box Canyon <br />permit revision. Sampling occurs at these wells seasonally <br />(three times a year). Parameters monitored include, water level, <br />pH, conductivity, temperature, total dissolved solids, total <br />suspended solids, total iron, and total manganese. <br />The quality of mine water discharges from the B Seam has <br />proven to be similar to those from [he F Seam. Underground or <br />mine water is permitted for discharge at the following locations: <br />Sylvester Gulch fan site, sediment pond MB-1, MB-2R, the <br />Sylvester Gulch mine water treatment facility, Lone Pine Gulch <br />and Minnesota Creek (not in service). Mine water is discharged <br />through Lone Pine mine water discharge pipe from the NW <br />panels sealed sump. Quality parameters appear to be such that <br />B Seam mine water will be suitable for treatment and discharge <br />under current NPDES/CPDES permit requirements to the North <br />Fork of the Gunnison River. <br />'t'he quantity of groundwater flows which would be potentially <br />discharged is low. Testing to date indicates the permeabilities in <br />and near the B Seam to be low. Water in storage, based on <br />testing in the B Seam and experience in the F Seam, is of low <br />quality. Fractures, from existing data, appear to be less <br />extensive and less open with increased depth and contact the <br />40 <br />