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The lower seam is well exposed to the northwest of the property at the Burnwell Mine (another <br />• 1940's operation which was never permitted since SMCRA). This seam has an average observed <br />thickness of 48 inches. This seam lies approximately 80 feet below the upper seam with inter- <br />bedded sandstone and shale between the seams. On an average, the upper seam lies 100 to 400 <br />feet below the surface of the mesa above Hay Gulch. <br />The King Coal operation predominately mines the upper coal seam from the Menefee during the <br />course of its operations. <br />Ground Water Hydrology <br />Two aquifers have been identified within the area potentially affected by the King Coal operation: <br />the Hay Gulch alluvial aquifer; and, the Point Lookout Sandstone. <br />The Hay Gulch alluvial aquifer, which is adjacent to the operation, averages 20 feet in depth and <br />had a cross sectional area of 25,200 square feet, with an estimated transmissivityof 70,400 gallons <br />per day per foot (gpolft.). The water table surface in this alluvial aquifer varies with seamen from <br />above ground surface to about 3 feet below the surface. The direction of flow in this unconfined <br />system is postulated to be in a downstream direction, parallel to the strike of Hay Gulch. <br />Recharge to the alluvium is from snowmelt and precipitation infiltration, and from the Menefee <br />Formation contact along the north side of Hay gulch. Sampling of this alluvialwater by National <br />King Coal indicates that the water is high in total dissolval solids. The poor quality of the water <br />• makes it unsuitable for domestic and irrigation purposes, but usable for stock watering. <br />An analysis of the probable effects of mining to tha aquifer indicate that very little effects would <br />be noted . Future operations in the Upper Menefee coal seam are not expectedto disrupt aquifers, <br />streams, waters systems, or the small watershed up slope of the mine site. Hydrologic data <br />obtained from existing workings, core drill holes, and other research studies show that the mining <br />operations have had only a mild impact on the water sources of Hay Gulch. The mine is not <br />located in a major groundwater recharge area. Research has shown this portion of the basin has <br />had very little ground water development.. Most of the wells in the general area have been <br />completed in the unconsolidated alluvial gravels and terrace deposited of the La Plata river and <br />its tributaries (including Hay Gulch), or in consolidated aquifers further south (down dip) in the <br />basin. The Point Lookout Sandstone aquifer, nearly 275 feet below the mine floor, to date has <br />been unaffected by mining operations. <br />With the exceptionof a very brief period in early 1986, all mineworkingshave been dry. All coal <br />within the permit area lies above the potentiometric surface of Hay Gulch therefore it is not <br />expected there will be any hydrologic consequences due to mining. <br />Ground water use in the vicinity of the mine is limited Within cone-mile radius of the facilities <br />area, one spring and three water wells have been identified. <br />. The Huntington Springs is located on the north side of Hay Gulch west of the La Plata No. I Mire <br />area (File No. C-87-072). This spring, which may issue from either the IowerMenefee Formation <br />4 <br />