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Groundwater has been monitored to observe the effects of mining in the alluvial <br />aquifer of Mann Draw. Water quality has been measured in the alluvium both <br />upgradient in Well 336 (upgradient of the impacts of mining) and downgradient <br />of the reclaimed mine area in Well 30C. As would be expected, there has been <br />some degradation of water quality at the downgradient site. Sodium, chloride, <br />sulfate, and total dissolved solids show increased levels downgradient of the <br />disturbance area. However, the concentrations of these constituents have <br />stabilized or even decreased over the last several years. Total dissolved solids, for <br />example, have decreased from a high of 2240 mg/l in 1984 to values averaging <br />1120 mg/l during 1997 and 1998 at the downgradient monitoring location. <br />Upgradient water chemistry is much more variable than the water leaving the site. <br />In fact, the upgradient well was dry for most of the sampling events in the 1990s, <br />and held measurable water again only in 1995 through 1998. The hydrochemistry <br />of the upgradient water fluctuates with the volume of water flowing through the <br />system. <br />The groundwater leaving the Bourg site has experienced the effects predicted in <br />the probable hydrologic consequences. There is an increase in total dissolved <br />solids (TDS) and a shift from a sodium bicarbonate to a sodium sulfate water. <br />This change has not created impacts because there are no water wells in the Mann <br />Draw alluvium between the Bourg Mine and the Canadian River and the <br />contribution of Mann Draw water to the total flow in the Canadian River alluvium <br />is insignificant. <br />No spoils springs or seeps have been identified.. <br />The conclusion is that there is no evidence of significant impacts to either surface <br />water or groundwater from the reclaimed Bourg Mine. Mining and reclamation <br />were done to minimize disturbance to the hydrologic balance in the mine and <br />adjacent areas. Surface water runoff has been controlled and mitigated through <br />the use of sedimentation ponds and revegetation of disturbed areas. All sediment <br />ponds were removed in 1988. There are no significant impacts to groundwater <br />because there are no identified downgradient groundwater receptors, and <br />increased concentrations of sodium, sulfate, and total dissolved solids at the <br />downgradient monitoring location have attenuated over time. <br />Summary and Conclusions <br />Based upon a review of the mine permit, the applicant's bond release application, <br />and site inspections, the Division finds that Flatiron Companies has successfully <br />completed all surface coal mining reclamation operations in accordance with the <br />approved reclamation plan and met all requirements of the Act and the Rules. <br />Bourg Mine 9 Final Bond Release <br />Permit No. C-8l-o? I January I8, 2000 <br />