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groundwater inflows are associated with fractures near the subcrop and are seasonal. As <br /> discussed in the previous section of this document, a fault system was encountered while <br /> development mining in the B Seam, which produced as much as 8,000 gpm of groundwater <br /> inflow to the mine. <br /> Groundwater use in the general area around the West Elk Mine is confined to shallow wells in <br /> the alluvium and Rollins Sandstone of the North Fork of the Gunnison River and its tributaries. <br /> No private, commercial, or industrial wells are presently located within the permit area. <br /> A description of the surface water system can be found in Section 2.04.7 of the permit <br /> document. Supporting information is contained in Map 34, which illustrates the drainages <br /> associated with the WEM coal lease area. Map 37, which delineates the location of all known <br /> springs on the coal lease area, and Map 36, which shows the reservoirs and irrigation ditches <br /> associated with the Minnesota Creek Basin. <br /> A description of the surface water occurrence and mining impacts on adjacent areas can be <br /> found in the "Probable Hydrologic Consequences of Mining" section of this document, and the <br /> "Cumulative Hydrologic Impact Study" document for this mine area. <br /> All of the streams draining the West Elk Mine permit area are tributaries to the North Fork of <br /> the Gunnison River. Lone Pine Gulch and Gribble Gulch are ephemeral streams draining the <br /> northern portion of the lease area. Sylvester Gulch is a perennial stream in its lower reaches <br /> through the mine area. Minnesota Creek and its tributaries, Horse Creek, South Prong, Lick <br /> Creek, Dry Fork, and East Fork, drain the southern portion of the coal lease area. Minnesota <br /> Creek enters the North Fork of the Gunnison River near Paonia. The overall drainage exhibits <br /> a dendritic drainage pattern with steep channels. Horse Creek and South Prong of the East <br /> Fork of Minnesota Creek are perennial streams, while Lick Creek, Upper Dry Fork, Sylvester <br /> Gulch and Gribble Gulch are ephemeral streams. Minnesota Reservoir controls much of the <br /> flow in the lower Dry Fork of Minnesota Creek, and Beaver Reservoir controls the flow in the <br /> East Fork of Minnesota Creek. Lone Pine Gulch has no evidence of recent flow; therefore, no <br /> gaging station has been constructed. Even when all of the six gaged watersheds were found to <br /> be flowing, Lone Pine Gulch showed no flow or evidence of flow. <br /> There are three different types of springs within the permit area including alluvial, colluvial, <br /> and bedrock springs. A study of the groundwater system at the West Elk Mine by Mayo & <br /> Associates showed that 83 different springs have been identified within the existing permit <br /> area. From the identified springs, 65% of the cumulative discharge volume comes from <br /> superficial springs in alluvium and/or colluvium. Only 5% of the discharge comes from units <br /> of the Upper and Lower Coal member. The flow rates of these springs are highly seasonal <br /> with peak flows occurring during wet weather conditions. <br /> Reservoirs and stock ponds also occur within or near the permit area. Minnesota Reservoir, <br /> on the Dry Fork of Minnesota Creek, is centrally located within the coal lease area. Beaver <br /> Reservoir on the East Fork of Minnesota Creek is located near the southwestern boundary of <br /> the coal lease area. <br /> 14 <br />