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Tract Delineation Report - 2003 The MCC WFT LBA Page 3 • The WFT has been delineated to include all potentially recoverable coal reserves in the B seam lying within the WFT as described above. All seams aze included in the event that any present a mineable portion within the WFT. The competitive lease application submitted by the MCC identified an area of approximately 923 acres more or less. In September of 2003, development in the 22LW gateroads and bleeders revealed that a portion of the WFT would indeed be unmineable. Due to that discovery, BLM and MCC agreed to amend the legal description to drop some lands in section 24, which resulted in an approximate acreage of 689. The minerals in the tract aze managed by BLM.while the surface estate is managed by the U.S.F.S. YV. ~eoloeie Data. Stratigr~hy. The tract is underlain by the Upper Cretaceous Mesaverde Formation and the Tertiary . Wasatch Formation, The Wasatch crops out on West Flatiron Mesa on the tract. In this area, the Mesaverde Formation contains two members, the upper member, called the barren member, is approximately 1500 feet thick consisting of interbedded sandstones and shales with a few prominent sandstone beds. This member comprises the majority of the exposed stratigraphy on the tract. The lower member, called the coal member, is about 500 to 700 feet thick which has at its base the Rollins Sandstone underlain by the Mancos Shale. The Upper and Lower Coal Members of the Mesaverde Formation contain the coal beds. The upper coal member contains approximately 220 feet of shales, siltstones, sandstones and three persistent coals recognized as the D, E and F seams. • The lower coal member consists of interbedded sandstones, siltstones, shales and coal. The member averages 270 feet and contains three recognized persistent coals, the A, B and C seams. The principle potentially mineable coal seam within the WFT azea is the "B" seam. Other seams within the tract, A, C, E, D, and F, are considered too thin (less than 8 feet) and discontinuous to mine. The "B" seam is approximately 50 feet above the Rollins sandstone. The seam occurs in three separate benches which coalesce to the west, northwest and southwest to thicknesses of 20 feet or greater. The benches begin to show partings in the west half of the WFT and drill hole data indicates that no single bench of the seam is thicker than 9 feet beyond the west boundary. In mine development does indicate this trend may fluctuate to the east, thus providing potential for mineable coal reserves. The "D" seam is approximately 250 feet above the "B" seam and consists of upper and lower splits, each less than 8 feet thick, and they are considered untnineable. Structural Settine. The Paonia-Somerset coal field is located in the southeastern end ofthe Piceance Basin. The area is bounded by Laramide structural and physiographic features: Grand Mesa to the north, Gunnison Uplift to the south, the Elk and West Elk Mountains to the east, and the Gunnison River drainage and Uncompahgre Plateau to the west. Structural GeoloQV and Geoloeic Hazazds. In the area of the WFT, the Mesaverde Formation strikes N75E to N85E and dips 4 to 7 degrees to the northeast. Landslide deposits are common throughout the azea. Unstable colluvial materials exist in the North Fork drainage. Their potential effect on an . underground mining operation such as the West Elk mine is expected to be negligible.