Laserfiche WebLink
<br /> <br />The Williams Fork Formation is divided into three hydrologic units: The <br />Sandstone Facies, which underlies the "A' coal seam and is generally <br />equivalent to the Trout Creek Sandstone and the upper portion of the Iles <br />Formation; the Siltstone and Coal Facies, which consists of the interbedded <br />coal, silts tone, and shale strata of the Lower Williams Fork Formation; and <br />the upper Sandstone Facies of the Upper Williams Fork Formation. <br />A fourth hydrologic unit is the alluvium of the White River and its <br />tributaries. The maximum thickness of the White River Alluvium near the <br />permit area was found to be 37 feet. Groundwater in the alluvium occurs in an <br />unconfined condition. <br />No major usage of groundwater in or adjacent to the permit area has been <br />defined by the permittee. Due to the generally low yield and poor quality of <br />aquifers in the region, high groundwater usage would be unusual. Recharge of <br />the bedrock aquifers occurs primarily at higher elevations north of the permit <br />area through infiltration of precipitation in outcrop areas. Discharge is <br />primarily through seeps where aquifers are erosionally exposed along the White <br />River. <br />Western fuels has developed an alluvial well field near the confluence of <br />Scullion Gulch and the White River. This alluvial water is used for mine <br />operations. In 1984, Kenney Reservoir was completed above Rangely, Colorado. <br />Kenney Reservoir impounds the White River through the southern portion of the <br />permit area, inundating Western Fuels-Utah's alluvial well field, and its <br />alluvial monitoring wells. Since the alluvial surface is almost completely <br />submerged by the reservoir, recharge to the well field is now instantaneous. <br />Movement of the Mesa Verde groundwater is controlled by the Red Wash Syncline <br />and major fracture zones located along Red Wash, Scullion Gulch, and the White <br />River. Groundwater in the northwest part of the permit area moves down dip to <br />the Red Wash Syncline. Within the central and southern portion of the permit <br />area, groundwater flows south to the White River. <br />Surface water drainage patterns in the area are incised and dendritic. <br />Scullion Gulch and Red Wash flow primarily in response to direct <br />precipitation. The White River is a perennial stream receiving discharge <br />from the permit and adjacent areas. The majority of flows in the White <br />River occur hetween May and July in response to snowmelt. <br />Soils in the area include the Cushman, Forelle, Pinelli, Potts, Satanka and <br />Worfka series, which are developed on ridge tops, ridge sideslopes, and in <br />valley fans. Underdeveloped soils such as Colorado, Haverson alkali phase, <br />Kinnear, Moyerson, Redcreek, Rentsac, and Turley variant occur on low <br />floodplains, extreme ridge tops, and upper ridge sideslopes. <br />Eight plant communities have been identified in the permit area to be affected <br />by surface operations and facilities. Vegetation communities consist of <br />juniper woodland, juniper woodland-big sagebrush, big sagebrush, big <br />sagebrush-wheatgrass, western wheatgrass, Colorado wildrye, cheatgrass-annual <br />forb, and big sagebrush-greasewood. These communities comprise a mosaic <br />controlled by soil type, topography, and past and present land uses. <br />Principal land use has been sheep winter range, resulting in overgrazing of <br />much of the permit area. The area is now characterized by a predominance of <br />disturbed vegetation types that are successional or dysclimactic in character. <br />-4- <br />