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Evidence shows that groundwater movement is controlled lazgely by fracture and topography. <br />The West Elk Mine's experience in mining the F and B Seams indicates that groundwater inflows <br />aze associated with fractures near the subcrop and aze seasonal. As discussed in the previous <br />section of this document, a fault system was encountered while development mining in the B <br />Seam, which produced as much as 8,000 gpm of groundwater inflow to the mine. <br />Groundwater use in the general area azound 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 aze presently located within or down-gradient adjacent the permit <br />azea, 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 azea, Map 37, which delineates the location of all known springs on the coal <br />lease azea, 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 azea aze 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 azea. Sylvester Gulch is a perennial stream in its lower reaches <br />through the mine azea. Minnesota Creek and its tributaries, Horse Creek, South Prong, Lick <br />Creek, Dry Fork, and East Fork, drain the southern portion of the permit azea. Minnesota Creek <br />enters the North Fork of the Gunnison River neaz Paonia. The overall drainage exhibits a <br />dendritic drainage pattern with steep channels. Horse Creek and South Prong of the East Fork of <br />Minnesota Creek are perennial streams, while Lick Creek, Upper Dry Fork, Sylvester Gulch and <br />Gribble Gulch are ephemeral streams. Minnesota Reservoir controls much of the flow in the <br />lower Dry Fork of Minnesota Creek, and Beaver Reservoir controls the flow in the East Fork of <br />Minnesota Creek. Lone Pine Gulch has no evidence of recent flow; therefore, no gaging station <br />has been constructed. Even when all of the six gaged watersheds were found to be flowing, Lone <br />Pine Gulch showed no flow or evidence of flow. Raven Creek flows through the extreme <br />northeast corner of the permit azea. It is encompassed by the permit and lease boundaries but a <br />stipulation expressly forbids mining such thak the affected azea would include the riparian zone <br />of the creek. <br />There are three different types of springs within the permit azea including alluvial, colluvial, and <br />bedrock springs. A study of the groundwater system at the West Elk Mine by Mayo & <br />Associates found 83 different springs within the existing permit azea in 1999. From the <br />identified springs, 65% of the cumulative dischazge volume comes from superficial springs in <br />alluvium and/or colluvium. Only 5% of the discharge comes from units of the Upper and Lower <br />Coal member. The flow rates of these springs aze highly seasonal with peak flows occurring <br />during wet weather conditions. <br />30 <br />