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Description of the Environment <br /> <br />Location of Permit Area <br /> <br />The Trapper Mine is located in Moffat County, Colorado on lands within: <br /> <br />Township 5 North, Range 90 West <br />Portions of Sections 4, 5, 6, 8 and 9 <br /> <br />Township 5 North, Range 91 West <br />Portions of Sections 1, 4, and 5 <br />All of Sections 2 and 3 <br /> <br />Township 6 North, Range 90 West <br />Portions of Sections 30, 32 and 33 <br />All of Section 31 <br /> <br />Township 6 North, Range 91 West <br />Portions of Sections 21, 25, 26, 27, 28, 29, and 32 <br />All of Sections 33, 34, 35, and 36 <br /> <br />Physiographic Setting <br /> <br />The Trapper Mine extends across the northern slope of the Williams Fork Mountains between <br />elevations of 6,500 ft. and 7,800 ft. The crest of the Williams Fork Mountains forms a long ridge <br />extending east/west at elevations between 7,400 and 7,800 ft. The Yampa River flows generally <br />from east to west a short distance north of the permit area. The Williams Fork River skirts the <br />south side of the mine site and flows into the Yampa River one mile west of the mine. <br /> <br />Geologic Setting <br /> <br />The bedrock at the ground surface in the Trapper Mine permit area is an interbedded sequence of <br />sandstones, siltstones, shale, and coals that are part of the Cretaceous-age Williams Fork <br />Formation. The Williams Fork Formation is part of the regionally extensive Mesa Verde Group. <br />The Williams Fork Formation crops out along a six-mile wide belt that extends along the entire <br />length of the Williams Fork Mountains. Younger unconsolidated alluvial deposits of Quaternary <br />age form a thin mantle on top of the Williams Fork Formation in stream drainages in the permit <br />area and surrounding areas. The alluvium is thickest in the Yampa and Williams Fork River <br />valleys. Structurally, the mine is situated on the south limb of the northwest-plunging Big <br />Bottom syncline. Major faults extend across the region, but none have been found in the permit <br />area. <br /> <br />Coal Seam Stratigraphy <br /> <br />The Williams Fork Formation is stratigraphically subdivided into three units or members. These <br />are, in ascending order, the lower Williams Fork, the Twentymile sandstone, and the upper <br />Williams Fork, with individual thicknesses of 920 ft., 100 ft., and 680 ft., respectively. The coal <br /> <br /> <br />14 <br /> <br />Trapper MineJuly 9, 2013 <br /> <br />