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spring and late summer/early fall. <br /> The mine is located in the White River Basin, which is the eastern portion of the larger Uinta <br /> Basin. The mine lies within the interbedded sandstone and siltstone strata of the Mesaverde <br /> Group in the Williams Fork Formation. The Mesaverde Group consists of the Lower Iles <br /> Formation and the Upper Williams Fork Formation, which are separated by the Trout Creek <br /> Sandstone. The Williams Fork Formation is further divided into upper and lower members. <br /> The Lower Williams Fork Member contains coal bearing seams "A" through "H." The "B" <br /> and "D" seams will be recovered at the Deserado Mine. <br /> The dip of the Mesaverde Group within the permit area is controlled by the asymmetric Red <br /> Wash Syncline, which strikes northwest southeast. Dips vary from 7 degrees in the southern <br /> part of the permit area, horizontal at the synclinal axis, to as much as 70 degrees on the north <br /> flank of the syncline. The coal and sandstone beds outcrop along this steep northern flank. <br /> Structure and local topography are the main factors that control ground water movement in the <br /> area. <br /> The Williams Fork Formation is divided into three hydrologic units: The Sandstone Facies, <br /> which underlies the "A" coal seam and is generally equivalent to the Trout Creek Sandstone <br /> and the upper portion of the Iles Formation; the Siltstone and Coal Facies, which consists of <br /> the interbedded coal, siltstone, and shale strata of the Lower Williams Fork Formation; and the <br /> upper Sandstone Facies of the Upper Williams Fork Formation. <br /> A fourth hydrologic unit is the alluvium of the White River and its tributaries. The maximum <br /> thickness of the White River Alluvium near the permit area was found to be 37 feet. <br /> Groundwater in the alluvium occurs in an unconfined condition. <br /> No major usage of groundwater in or adjacent to the permit area has been defined by the <br /> permittee. Due to the generally low yield and poor quality of aquifers in the region, high <br /> groundwater usage would be unusual. Recharge of the bedrock aquifers occurs primarily at <br /> higher elevations north of the permit area through infiltration of precipitation in outcrop areas. <br /> Discharge is primarily through seeps where aquifers are erosionally exposed along the White <br /> River. <br /> The operator had originally developed an alluvial well field near the confluence of Scullion <br /> Gulch and the White River to supply water for mine operations. In 1984, Kenney Reservoir <br /> was completed above Rangely, Colorado. Kenney Reservoir impounds the White River <br /> through the southern portion of the permit area, inundating much of the alluvial well field. <br /> Because the alluvial surface is almost completely submerged by the reservoir, recharge to the <br /> alluvium is now instantaneous. Due to inundation of the well field by the reservoir, and due to <br /> high salinity of the alluvial well water, the operator now pumps water directly from the White <br /> River into an adjacent lagoon, and from there, water is pumped to the mine's raw water <br /> storage tank. . Only one alluvial well, Qal-5, located at the mouth of Scullion Gulch, remains <br /> in use as a monitoring well. <br /> 10 <br />