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• -5 • DESCRIPTION OF THE ENVIRONMENT The Trapper Mine is located on the northern slope of the Williams Fork moun- tains between approximately 6,500 and 7,500' elevation. The Yampa River flows generally west to east to the north of the permit area, while the Williams Fork River flows into the Yampa from the south, and is located south of the permit area. Land uses in the area consist of rangeland, wildlife habitat, and agriculture. Cattle and sheep are grazed in the Williams Fork mountains and on the toe- slopes of the mountains in the spring and fall. Dryland wheat is cultivated in favorable areas on the colluvial toe-slopes of the Williams Fork mountains. Native hay and some dryland wheat is cultivated on the soils of the Yampa and Williams Fork River valleys. The Williams Fork mountains provide habitat and migration routes for the large game ungulates, elk and mule deer. Raptors, several species of game birds, and numerous smaller mammals are found in the Williams Fork mountains, and surrounding areas. The Trapper Mine is located on the north-facing slope of the Williams Fork moun- tains. The crest of the Williams Fork mountains forms a Long ridge running east-west at elevations between 7,400 and 7,700 feet. The mine is located on a near dip-slope, with the strata dipping slightly more than the slope of the topography. Two recognized bedrock formations outcrop in the immediate vicinity of the mine; the Williams Fork formation of the Mesa Verde Group, and the Lewis Shale for- mation. Unconsolidated alluvial deposits are found in the valleys of the Yampa and Williams Fork Rivers, and portions of several ephemeral drainages adjacent to the mine area. The Williams Fork formation is conformably overlain by the Lewis Shale formation. The coal seams being recovered at the Trapper Mine (R, I, L, Q, 4 rider, and R rider) exist wholly within the Williams Fork formation. The williams Fork formation is stratigraphically subdivided into three units. They are, in ascending order, the Lower Williams Fork, the Twenty Mile Sand- stone, and the Upper Williams Fork members,~with individual thicknesses of 920', X00' and 680' respectively. The Upper williams Fork member is the only bedrock strata proposed to be disturbed by mining. No major faults have been identified in the vicinity of the mine, which lies on the south Limb of the Big Bottom Syncline. Trapper Mine is situated on the north slope of the drainage divide between the Yampa River and a major Yampa River tributary, the Williams Fork River. Drain- ages within and adjacent to the permit area (on the north-facing slope) run south to north down the slope and are dendritic in pattern. Within the permit area are portions of the following drainages: Coyote, Noname, Johnson, Pyeatt, and Flume. These drainages are ephemeral and flow primarily in response to snowmelt and/or heavy rains. All of these ephemeral drainages discharge eventually into the Yampa River.