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Consequences of Mining" section of this document and the "Cumulative <br /> Hydrologic Impact Study" document for this mine area. <br /> The ground water systems relevant to mining activities in the region are the <br /> alluvial deposits associated with streams and the Mesaverde Formation. Ground <br /> water use in the general area around the West Elk Mine is confined to shallow <br /> wells in the alluvium and Rollins Sandstone of the North Fork of the Gunnison <br /> River and its tributaries. <br /> The west Elk Mine's experience in mining the F and B seams indicates that <br /> ground water inflows are associated with fractures near the subcrop and are <br /> seasonal. Evidence suggests; that ground water movement is controlled largely <br /> by fracture patterns and topography. <br /> There are seven categories of potential aquifers that occur in the Somerset <br /> Coal Field. These are: 1) the alluvial and terrace deposits associated with <br /> the North Fork of the Gunnison River; 2) the localized, shallow alluvium along <br /> creeks tributary to the North Fork; 3) the discontinuous, lenticular and <br /> laminar sandstones of the Mesaverde Formation; 4) the Rollins Sandstone; <br /> 5) the coal seams; 6) shallow colluvial surficial deposits; and 7) fracture <br /> zones in bedrock. <br /> The most continuous sandstone aquifers of any significance in the region are <br /> the Rollins Sandstone and the massive sandstone separating the upper and lower <br /> Coal members of the Mesaverde Formation. However, the latter massive <br /> sandstone produces very little water, as evidenced by the dryness of the Bear <br /> Mine and the lack of springs associated with this unit. The Mesaverde <br /> Formation tends to be dry, or the rock units are of such a low permeability, <br /> they yield insufficient water for sustained use or mine discharge. The <br /> sandstones are lenticular and discontinuous and are usually highly cemented. <br /> A description of the surface: water system can be found in Section 2.04 .7 of <br /> the permit application. Supporting information is contained in Map 34, which <br /> illustrates the drainages associated with the WEM coal lease area, Map 37 and <br /> 37A, which delineates the location of all known springs on the coal lease <br /> area, and Map 36, which shows the reservoirs and irrigation ditches associated <br /> with the Minnesota Creek Basin. <br /> A description of the surface water occurrence and mining impacts on adjacent <br /> areas can be found in the "Probable Hydrologic Consequences of Mining" section <br /> of this document, and the "Cumulative Hydrologic Impact Study" document for <br /> this mine area. <br /> All of the streams draining the West Elk Mine permit area are tributaries to <br /> the North Fork of the Gunnison River. Sylvester Gulch, Lone Pine Gulch, and <br /> Gribble Gulch are ephemeral streams draining the northern portion of the lease <br /> 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 <br /> area. Minnesota Creek enters the North Fork of the Gunnison River near <br /> Paonia. The overall drainage exhibits a dendritic drainage pattern with steep <br /> channels. Horse Creek and South Prong of the East Fork of Minnesota Creek are <br /> perennial streams, while Lick Creek, Upper Dry Fork, Sylvester Gulch and <br /> 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 <br /> the flow in the East Fork of Minnesota Creek. Lone Pine Gulch has no evidence <br /> of recent flow; therefore, no gaging station has been constructed. Even when <br /> all of the six gaged watersheds were found to be flowing, Lone Pine Gulch <br /> showed no flow or evidence of flow. <br /> Geolocry - Rules 2.04 .5 and 2.04 .6 <br /> The applicant describes the geology of the permit and adjacent area in <br /> Section 2 .04 .5 of the permit application. Additional information is detailed <br /> on Map 9 and 9A, which details the geology of the lease area, as well as the <br /> coal outcrop line and the strike and dip for the F and B seams. Stratigraphic <br /> cross-sections are shown on Maps 10, 11, 11A, and 12 . <br /> 6 <br />