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III. AFFECTED ENVIRONMENT A detailed description of the existing environment can be found in the West Elk Mine and Reclamation Plan, 1991, West Central Coal EIS, 1979, Uinta Southwest Utah Coal EIS, 1983 Coal Unsuitability Report for the Bookcliff and Paonia/Somerset Coal Planning Areas within the Uncompahgre Basin Planning Area, 1989, the Uncompahgre Basin Resource Management Plan EIS, 1989, and the Amended Land and Resource Management Plan -Grand Mesa, Uncompahgre and Gunnison Narional Forests, 1991. A brief description of the specific resources that are within the Box Canyon Tract is detailed below. A. Minerals The Box Canyon Tract lies in the Paonia-Somerset coal field which contains medium to high coal development potential deposits. The main coal beds within the area are found in the Upper Cretaceous Mesaverde Formation, which is overlain by the early Tertiary Wasatch Formation and underlain by the Upper Cretaceous Mancos Shale. The two principle mineable coal seams are in ascending order, the "B" and "E/D" seams. Other seams within the tract, A, C, and F, are considered too thin (less than 6 feet) and discontinuous to mine. Tfie Upper B seam ranges in thickness from 9 to 16 feet. The average analysis of the coal seam is 5.66°h moisture, 7.66% ash, 0.57% sulfur and 12,975 Btu's per pound. The tract contains an estimated 67 million tons of in-place 8 coal seam reserves. The D/E seam ranges in thickness from 6 to 12 feet. A large portion of the D/E reserves are not mineable because of coal thickness and known conditions of poor roof and/or partings creating difficulties with extraction. The D/E seam analytical data averaged around as follows: 9.31 °h ash, 6.45°~ moisture, 0.57°,6 sulfur and 12,162 Btu's. The tract contains an estimated 17 million tons of in-place D/E seam reserves. The total in-place coal reserves are approximately 84 million tons of which 37 million tons are recoverable. Outcropping on the tract is the Tertiary Wasatch Formation, Upper Cretaceous Mesaverde Formation and Quaternary deposits. The Quaternary deposits are an unsorted mixture of soil and rock formed by various mass-wasting processes as landslides, earth flows, soil creep and debris avalanches. They also include river deposits and slope colluvium as well as Quaternary unconsolidated deposits derived from the Wasatch Formation. The coal bearing sedimentary strata of the Mesaverde Formation is relatively flat lying with a regional dip of 3.5 degrees to the north-northeast. Local dips of up to 7.0 degrees are also found. Exploration drilling on and in the area of the tract is not adequate to precisely locate the trace of any fault or other finite structural feature within the tract. However, USGS Map C-115, compiled by R. Dunrud shows lineaments visible from aerial photography along Sylvester Gulch and parallel to several drainages. The overburden overlying the B seam in the application area ranges from 250 feet at the northern boundary of the tract to approximately 2,200 feet under West Flatiron Mesa. The potential for the discovery of conventional resources of oil and gas under the leased area is very slight. Dry wells have been drilled to the Dakota Sandstone a few miles to the southwest and to the northwest of the permit area. There is a possibility of finding methane in the coal seams. There are no ail and gas leases located on or near the application area. B. Vegetation The vegetation of the application lands is comprised of scrub oak and sagebrush with an understory of grasses. There are stands of aspen and Engelmann spruce-Douglas fir on the upper north facing slopes. The grasses and mountain shrubs that have been identified are western wheatgrass, Indian ricegrass, oak brush, serviceberry, chokecherry, sagebrush, mountain brome and junegrass. There is a unique riparian zone within the Box Canyon drainage. A Gambel oak, hawthorne and chokecherry community is present for the first 1 /3 mile. A small grove of narrow-leaf cottonwood Page 5