Laserfiche WebLink
build within the pile and cause the water to migrate laterally to a <br /> small seepage area at the edge of the site. There have been no <br /> visible flows from the pile toe and mid-section underdrain. <br /> 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 /> There will be no uncontrolled mine water discharge after mining <br /> is complete that will significantly degrade surface water or <br /> groundwater. The operation plan indicates most water used for <br /> dust control will be adsorbed on the coal and carried from the <br /> mine, thereby minimizing the quantity to be treated. Any <br /> discharge will be treated in the sedimentation ponds and <br /> discharged as specified in the NPDES permit. <br /> The required ground water monitoring plan for the West Elk <br /> Mine is described in Exhibit 71 for the South of Divide and Dry <br /> Fork lease areas, and in Table 5, Section 2.04 of the permit <br /> application for other areas. MCC monitors water quality and <br /> water levels in 27 wells in the permit area. Monitoring wells are <br /> completed in the following stratigraphic units (in ascending <br /> order): the B-seam, the E-seam, a stratigraphic interval between <br /> the E and F seams, the F-seam, the Barren Member, and <br /> Quaternary alluvium. More than one well is completed in most of <br /> the stratigraphic units. Sampling occurs seasonally(three times a <br /> year). Parameters monitored include: water level, pH, <br /> conductivity, temperature, total dissolved solids, total suspended <br /> solids, total iron, and total manganese. <br /> Underground or mine water is permitted for discharge at the <br /> following locations: Sylvester Gulch fan site, sediment pond <br /> MB-1, the Sylvester Gulch mine water treatment facility, Lone <br /> Pine Gulch and Minnesota Creek. The Lone Pine discharge has <br /> been discontinued, and the portals have been sealed. Mine water <br /> is discharged through the main portals to MB-5E and from the <br /> mine water treatment facility to Sylvester Gulch. Quality <br /> parameters appear to be such that B-seam mine water will be <br /> suitable for treatment and discharge under current NPDES/CDPS <br /> permit requirements to the North Fork of the Gunnison River. <br /> The quality of mine water from the E-seam workings can be <br /> expected to be similar to water from the B-seam workings, based <br /> on the similar depositional origin of these two seams. <br /> 45 <br />