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are predicted to fill with water up to a maximum elevation equal to the portal <br /> elevation over a time period of less than 22 years. <br /> In addition to salt loading of streams, PSCM activities are predicted to result <br /> in the following impacts: <br /> Spoil leachate from the reclaimed surface mine pits will continue to load <br /> alluvial ground water with salts in the Little Grassy, Grassy, and Cow Creek <br /> drainages. As the alluvial/colluvial water quality closely mirrors the quality <br /> of the stream, a degradation (i.e. increase in TDS) is expected to be observable <br /> in alluvial monitoring wells down-gradient of the mine site. The Division has <br /> previously found that in portions of the Little Grassy Creek drainage that are <br /> in contact with previously disturbed lands, TDS increase over baseline <br /> conditions is observable (Seneca II Mine findings). <br /> The potentiometric surface of the Trout Creek Sandstone will continue to be <br /> depressed by the mine operator's pumping of water from this unit in their <br /> supply well located in the mine facilities area. The pumping rate will be <br /> subject to PSC's water rights associated with this well. PSCM predicts no <br /> impacts to potential aquifers above the Trout Creek Sandstone from pumping <br /> the well, based on the presence of thick intervening shale beds that act as <br /> aquicludes. <br /> Removing coal in the underground workings will cause ground water inflow <br /> into the mine void, resulting in drawdown of the potentiometric surface in the <br /> Wadge coal seam around the perimeter of the workings. The drawdown will <br /> extend into beds immediately above and below the coal seam. Maximum <br /> inflow of ground water into the workings is predicted to be 75 gallons per <br /> minute, including less than 2 gallons per minute of predicted spoil leachate <br /> inflow from surface mine pits that are up dip from the underground workings. <br /> Section 2.05 .6(3)(b)(iii) of the permit application contains an analytic <br /> simulation of the drawdown for three points in time after commencement of <br /> underground mining: 2 years, 5 years (end of first permit term), and 35 years <br /> (30 years after first permit term), with no mining beyond the current non-treat <br /> room and pillar proposal. Figure 2.05.6-F4.2 in the permit application shows <br /> predicted drawdown contours for the Wadge coal potentiometric surface. The <br /> contours indicate drawdown at the location of the seam's outcrop on the <br /> northeast flank of the Fish Creek Anticline will exceed 50 feet during the <br /> initial five-year permit term, and then will recover to a drawdown of less than <br /> 5 feet after mining ceases. The Wadge coal seam at this location is within the <br /> Trout Creek Sandstone-Twentymile Sandstone outcrop belt that has been <br /> reported as contributing to Grassy Creek flows (page 38 of U. S. Geological <br /> Survey publication titled Evaluation of the upper part of the Mesaverde <br /> Group, Northwestern Colorado, Water-Resources Investigations Report 90- <br /> 4020, by S.G. Robson and Michael Stewart). Seepage out of the outcrop belt <br /> was reported as contributing approximately 20% of Grassy Creek's instream <br /> 16 <br />