2009-09-21_GENERAL DOCUMENTS - C1981010

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Description of the Environment Location of Permit Area The Trapper Mine is located in Moffat County, Colorado on lands within: Township 5 North, Range 90 West Portions of Sections 5 and 6 Township 5 North, Range 91 West Portions of Sections 1, 4, and 5 All of Sections 2 and 3 Township 6 North, Range 90 West Portions of Sections 30 and 32 All of Section 31 Township 6 North, Range 91 West Portions of Sections 21, 25, 26, 27, 28, 29, and 32 All of Sections 33, 34, 35, and 36 Ph sib aphic Setting The Trapper Mine extends across the northern slope of the Williams Fork Mountains between elevations of 6,500 ft. and 7,800 ft. The crest of the Williams Fork Mountains forms a long ridge extending east/west at elevations between 7,400 and 7,800 ft. The Yampa River flows generally from east to west a short distance north of the permit area. The Williams Fork River skirts the south side of the mine site and flows into the Yampa River one mile west of the mine. Geologic Setting The bedrock at the ground surface in the Trapper permit area is an interbedded sequence of sandstones, siltstones, shale, and coals that are part of the Cretaceous-age Williams Fork Formation. The Williams Fork Formation is part of the regionally extensive Mesa Verde Group. The Williams Fork Formation crops out along a six-mile wide belt that extends along the entire length of the Williams Fork Mountains. Younger unconsolidated alluvial deposits of Quaternary age form a thin mantle on top of the Williams Fork Formation in stream drainages in the permit area and surrounding areas. The alluvium is thickest in the Yampa and Williams Fork River valleys. Structurally, the mine is situated on the south limb of the northwest-plunging Big Bottom syncline. Major faults extend across the region, but none have been found in the permit area. Coal Seam Stratigraphy The Williams Fork Formation is stratigraphically subdivided into three units or members. These are, in ascending order, the lower Williams Fork, the Twentymile sandstone, and the upper Williams Fork, with individual thicknesses of 920 ft., 100 ft., and 680 ft., respectively. The coal Trapper Mine 11 September 21, 2009