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the North Fork consists of mixed sand, cobbles, and boulders capped by finer sands and silts. <br />The quantity of groundwater produced from the alluvial deposits is dependent upon the thickness <br />and extent of the deposit. <br />Evidence shows that groundwater movement is controlled largely by fractures and topography. <br />The West Elk Mine's experience in mining the F and B Seams indicates that groundwater inflows <br />are associated with fractures and are seasonal. As discussed in the previous section of this <br />document, a fault system was encountered while development mining in the B Seam, which <br />produced as much as 8,000 gpm of groundwater 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 of the North Fork of the Gunnison River and its tributaries. No private, <br />commercial, or industrial wells are presently located within or down-gradient adjacent the permit <br />area, other than the infiltration gallery which supplies domestic water for the town of Somerset <br />and mine water for Oxbow Mining. <br />A description of the surface water system can be found in Section 2.04.7 of the permit document. <br />Supporting information is contained in Map 34, which illustrates the drainages associated with <br />the WEM coal lease area, Map 37, which delineates the location of all known springs on the coal <br />lease area, and Map 36, which shows the reservoirs and irrigation ditches associated with the <br />Minnesota Creek Basin. <br />A description of the surface water occurrence and mining impacts on adjacent areas can be found <br />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 the <br />Gunnison River. Lone Pine Gulch and Gribble Gulch are ephemeral streams draining the <br />northern portion of the permit area. Sylvester Gulch has perennial flows 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 permit area. Deep Creek drains <br />the eastern portion of the permit area. Minnesota Creek enters the North Fork of the Gunnison <br />River near Paonia. The overall drainage exhibits a dendritic drainage pattern with steep <br />channels. Horse Creek, South Prong of the East Fork, and Deep Creek are perennial streams. <br />Lick Creek, Upper Dry Fork, upper Sylvester Gulch and Gribble Gulch are ephemeral streams. <br />Minnesota Reservoir controls much of the flow in the lower Dry Fork of Minnesota Creek, and <br />Beaver Reservoir controls the flow in the East Fork of Minnesota Creek. Lone Pine Gulch has <br />no evidence of recent flow; therefore, no gaging station has been constructed. Even when all of <br />the six gaged watersheds were found to be flowing, Lone Pine Gulch showed no flow or <br />evidence of flow. Raven Creek flows through the extreme northeast corner of the permit area, <br />but a permit stipulation expressly forbids mining activities to expand the affected area into the <br />riparian zone of the creek. <br />There are three different types of springs within the permit area: alluvial, colluvial, and bedrock <br />springs. A study of the groundwater system at the West Elk Mine by Mayo & Associates found <br />83 different springs within the existing permit area in 1999. From the identified springs, 65% of <br />the cumulative discharge volume comes from superficial springs in alluvium and/or colluvium. <br />11