1996-06-25_GENERAL DOCUMENTS - C1980007

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will be mined by MCC during this permit term. This horizon has been mined and is currently being mined at the Somerset Mine. The C horizon contains one coal seam that occurs 50 to 100 feet above the B horizon. This horizon has been mined at U.S. Steel's Elk Creek Mine (now within the Sanborn Creek Mine permit area) and the Bear No. 1 and 2 Mines, and is currently mined at the Bear No. 3 Mine. The top of the member is usually capped by a massive buff-colored sandstone up to 90 feet in thickness. This sandstone, however, appears not to be a single persistent bed, but is actually several thick lenticular sandstones occurring at progressively lower stratigraphic horizons from east to west. The Upper Coal Bearing (Paonia) Member consists of 200 to 500 feet of gray shales, interbedded, buff-colored, lenticular sandstones, and coals. The top of this member is generally considered to be capped by a massive, cliff-forming sandstone. Three coal horizons have been identified in the Upper Coal Member, the D (Oliver) horizon, the E (Hawk's Nest) horizon, and the F horizon. The D horizon occurs directly above the massive sandstone of the Lower Coal Bearing Member and contains three seams. This horizon is currently mined in the Orchard Valley Mine. The E horizon occurs about 130 feet above the D horizon and contains two coal seams. This horizon has been mined at the Hawk's Nest Mine and was mined at the Blue Ribbon Mine. The West Elk Mine plans to mine the E Seam in the future. It will not be mined on Jumbo Mountain because the E Seam is split and comprised of several thin (< 5 ft.) coal benches which are separated by rock partings. The F horizon contains two coal seams and has been mined at the West Elk Mine. At the mine site, the coal is immediately overlain and underlain by shale. Coal seams of the F horizon do not exist to the north of the North Fork of the Gunnison River in thicknesses sufficient for mining. In the Jumbo Mountain area, the F Seam thins to less than five feet in thickness and is of limited aerial extent. Therefore, MCC does not plan to mine this seam in Jumbo Mountain. Overlying the Upper Coal Member is the Barren Member of the Mesaverde Formation. This unit consists of interbedded sandstones, siltstones, shales, and coals. The unit is not thought to be of marine origin and, as a result, the sandstones and the coals are highly lenticular, discontinuous, and of limited lateral extent in outcrop. This unit ranges up to 1,500 feet thick and outcrops throughout most of the five-year permit area. The Ohio Creek Member is the uppermost member of the Mesaverde Group. This unit is approximately 700 feet thick and consists primarily of interbedded sandstone, mudstone, and shale. The sandstones range from a few feet to more than 100 feet in thickness and are generally lenticular in nature. Although typically fine to coarse grained, the sandstones may locally be conglomeratic. The Mesaverde Formation is unconformably overlain by the Tertiary Age Rudy or Wasatch Formation. This formation consists of red to buff-colored shales, red sandstones, and red to gray conglomerates. The sediments of this formation are weathered volcanic rocks. The alluvium of the North Fork of the Gunnison River consists of Quaternary Age deposits of mixed coarse sand, cobbles and boulders. These coarse sediments are composed primarily of igneous and metamorphic rock types, and have their source area in the headwaters and upper reaches of the North Fork. This coarse alluvium is capped by finer sands and silts. The North Fork alluvium in the area of the Hawk's Nest, Bear, West Elk and Somerset Mines is fairly narrow in width and is between 50 and 70 feet thick. About a mile below the 8