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Minnesota Reservoir results in a decrease in total suspended solids (TSS) <br /> or turbidity, a slight increase in temperature, dissolved oxygen(DO), and <br /> total dissolved solids (TDS). The increase in TDS is most likely a result <br /> of evaporation losses. There is a slight increase in alkalinity and, as a <br /> result, a slight increase in pH. In all likelihood, these changes are also a <br /> result of evaporation losses. All of the changes in water quality observed <br /> are what would be expected as a result of impounding water in a shallow <br /> reservoir in a semi-arid climate. <br /> There are three different types of springs within the permit area including <br /> alluvial, colluvial, and bedrock springs. Eighty-three springs have been <br /> identified within the permit area. Recent data indicate that 65 percent of <br /> the discharge originates from alluvium and/or colluvium, and 35 percent <br /> have bedrock formation as their source. Only 5 percent of discharge <br /> comes from the Upper and Lower Coal Series. The flow rates of these <br /> springs are highly seasonal, with peak flows occurring during wet <br /> weather conditions. Measurements indicate that spring flows generally <br /> decrease from a high in the early summer to a low in the fall. A number <br /> of the springs are ephemeral, indicating that their sources are small <br /> localized aquifers (i.e. landslide deposits, colluvium, lenticular <br /> sandstones, etc.). There are a total of nineteen(19) decreed spring water <br /> rights on or near the West Elk Mine permit area. <br /> Wetlands have also been identified within the permit area. Based on <br /> inspection of conventional and infra-red aerial photographs and <br /> reconnaissance-level field investigation, there are estimated to be <br /> approximately 77 acres of wetlands in the permit area. Most of the <br /> wetlands are found in drainage channels, although there are small, <br /> isolated wetlands on the hillsides where springs and seeps occasionally <br /> emerge as a result of landslides/sumps. <br /> 2. Probable Hydrologic Consequences <br /> Section 2.05.6(3) of the permit application contains the applicant's prediction <br /> of the probable hydrologic consequences from mining and reclamation <br /> activities at the West Elk Mine. <br /> During the first two permit terms, the operator mined the F-seam. During the <br /> third through fifth permit terms, MCC mined the B-seam exclusively. <br /> Activity in these seams involve longwall mining methods, with very little or <br /> no activity in the F-seam. During the sixth permit term MCC conducted <br /> development and longwall mining in the B-seam and E-seam. During the <br /> current permit term, MCC will be conducting development and longwall <br /> mining in the E-seam. <br /> The Probable Hydrologic Consequences section of the permit is divided into <br /> two main subsections: Groundwater Effects and Surface Water Effects. <br /> 42 <br />