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The Lower Coal Bearing (Bowie) Member consists of 260 to 350 feet of interbedded gray shales, <br />thin to thick lenticular beds ofbuff-colored, fine- to medium-grained sandstones, and coals. <br />Three coal horizons exist in this member, the A (Old King) horizon, the B (Somerset) horizon, <br />and the C (Bear) horizon. The A horizon is immediately above the Rollins Sandstone and is not <br />currently mined at any operation in the vicinity. The B horizon contains two coal seams and <br />occurs about 20 to 120 feet above the Rollins Sandstone and will be mined by MCC during this <br />permit term. This horizon has been mined and is currently being mined at the Somerset Mine. <br />The C horizon contains one coal seam that occurs 50 to 100 feet above the B horizon. This <br />horizon has been mined at U.S. Steel's Elk Creek Mine (now within the Sanborn Creek Mine <br />permit azea) and the Beaz No. 1 and 2 Mines, and is currently mined at the Beaz No. 3 Mine. The <br />top of the member is usually capped by a massive buff-colored sandstone up to 90 feet in <br />thickness. This sandstone, however, appears not to be a single persistent bed, but is actually <br />several thick lenticular sandstones occurring at progressively lower stratigraphic horizons from <br />east to west. <br />The Upper Coal Bearing (Paonia) Member consists of 200 to 500 feet of gray shales, <br />interbedded, buff-colored, lenticular sandstones, and coals. The top of this member is generally <br />considered to be capped by a massive, cliff-forming sandstone. Three coal horizons have been <br />identified in the Upper Coal Member, the D (Oliver) horizon, the E (Hawk's Nest) horizon, and <br />the F horizon. The D horizon occurs directly above the massive sandstone of the Lower Coal <br />Bearing Member and contains three seams. This horizon is currently mined in the Orchazd <br />Valley Mine. The E horizon occurs about 130 feet above the D horizon and contains two coal <br />seams. This horizon has been mined at the Hawk's Nest Mine and was mined at the Blue Ribbon <br />Mine. The West Elk Mine plans to mine the E Seam in the future. It will not be mined on <br />Jumbo Mountain because the E Seam is split and comprised of several thin (< 5 ft.) coal benches <br />which are separated by rock partings. The F horizon contains two coal seams and has been <br />mined at the West Elk Mine. At the mine site, the coal is immediately overlain and underlain by <br />shale. Coal seams of the F horizon do not exist to the north of the North Fork of the Gunnison <br />River in thicknesses sufficient for mining. In the Jumbo Mountain azea, the F Seam thins to less <br />than five feet in thickness and is of limited aerial extent. Therefore, MCC does not plan to mine <br />this seam in Jumbo Mountain. <br />Overlying the Upper Coal Member is the Barren Member of the Mesaverde Formation. This unit <br />consists of interbedded sandstones, siltstones, shales, and coals. The unit is not thought to be of <br />marine origin and, as a result, the sandstones and the coals aze highly lenticular, discontinuous, <br />and of limited lateral extent in outcrop. This unit ranges up to 1,500 feet thick and outcrops <br />throughout most of the five-year permit area. <br />The Ohio Creek Member is the uppermost member of the Mesaverde Group. This unit is <br />approximately 700 feet thick and consists primarily of interbedded sandstone, mudstone, and <br />shale. The sandstones range from a few feet to more than 100 feet in thickness and are generally <br />lenticular in nature. Although typically fine to coarse grained, the sandstones may locally be <br />conglomeratic. <br />28 <br />