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Sandstone. The Williams Fork Formation is further divided into upper and lower members. The <br /> Lower Williams Fork Member contains coal bearing seams "A" through "H." The "B" and "D" <br /> seams will be recovered at the Deserado Mine. The B seam is presently being mined; the D <br /> seam is no longer being mined. <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 part <br /> of the permit area, horizontal at the synclinal axis,to as much as 70 degrees on the north flank of <br /> the syncline. The coal and sandstone beds outcrop along this steep northern flank. Structure and <br /> local topography are the main factors that control ground water movement in the 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 and <br /> the upper portion of the Iles Formation; the Siltstone and Coal Facies,which consists of the <br /> interbedded coal, siltstone, and shale strata of the Lower Williams Fork Formation; and the upper <br /> 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 was <br /> completed above Rangely, Colorado. Kenney Reservoir impounds the White River through the <br /> southern portion of the permit area, inundating much of the alluvial well field. Because the <br /> alluvial surface is almost completely submerged by the reservoir, recharge to the alluvium is now <br /> instantaneous. Due to inundation of the well field by the reservoir, and due to high salinity of the <br /> alluvial well water,the operator now pumps water directly from the White River into an adjacent <br /> lagoon, and from there, water is pumped to the mine's raw water storage tank. Only one alluvial <br /> well, Qal-5, located at the mouth of Scullion Gulch,remains in use as a monitoring well. <br /> The Red Wash Syncline and associated major fracture zones located along the Red Wash, <br /> Scullion Gulch and the White River control movement of the Mesaverde groundwater. <br /> Groundwater in the northwest part of the permit area moves down dip to the Red Wash Syncline. <br /> Within the central and southern portion of the permit area, groundwater flows south to the White <br /> River. <br /> Surface water drainage patterns in the area are incised and dendritic. Scullion Gulch and Red <br /> Wash flow primarily in response to direct precipitation. The White River is a perennial stream <br /> v <br />