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characteristics of the soil in the area is primarily due to slope and topography. Deeper soils are located in the valley bottoms and at the foot of slopes while the shallower soils occupy the steeper side slopes. Geology The Coal Ridge No. 1 Mine plans to extract coal from the lower portion of the Williams Fork Formation in the southern end of the Grand Hogback. The Grand Hogback trends east-southeast in the vicinity of the proposed mine with the rock strata dipping to the south-southwest at an average of 60 degrees. Although the rock strata dip ranges from 30 to 70 degrees, there is little evidence of faulting along the Grand Hogback. Minor folds trending north-south to northwest-southeast occur throughout the region. The exposed rock sequence in the permit area is Jurassic through Tertiary in age and includes (proceeding from the base to the top, oldest to youngest) the Morrison Formation, Dakota Sandstone, Mancos Shale, the coal-bearing Mesaverde Group, and the Wasatch and Ohio Creek formations. The Mancos Shale forms strike valleys along the Grand Hogback, including the proposed facility area. It consists of two marine shale members separated by a limestone member and is at least 4,000 feet thick in the mine area. The Mesaverde Group conformably overlies the Mancos Shale and ranges in thickness from 4,760 feet near South Canyon to 4,895 feet near New Castle (Collins, 1979). The Group's stratigraphy includes interbedded and lenticular sandstones, shale, siltstone, and coal beds. In ascending order (oldest to youngest), the Group contains (1) the Corcoran Sandstone, a marine shale sequence, and the Rollins Sandstone; (2) the Bowie (coal-bearing) member; (3) the Paonia (coal-bearing) member; and (4) the Upper (non-coal bearing) member. The Corcoran and Rollins Sandstones are the bottom and top, respectively, of the Iles formation, and the upper three members belong to the Williams Fork formation (see Figure 3.3-3 in the permit application). Williams fork Formation The two coal-bearing members of interest in the mine area are the Bowie and Paonia members. The Bowie member is about 1,000 feet thick near South Canyon and 960 feet thick near New Castle and consists of four general units. They are, in ascending order: (1) a coal-bearing shale unit 450 feet thick (containing the Lower Wheeler, Wheeler, and the D Coal Seams); (2) a sandstone unit (Middle Sandstone) 50 to 150 feet thick, similar texturally and mineralogically to the Rollins sandstone; (3) a 200-foot-thick shale unit which contains thin coal seams, including the Allen and possibly the Anderson, near South Canyon; and (4) and Upper Sandstone unit 50 to 150 feet thick, also similar in composition to the Rollins Sandstone. The Wheeler Coal Seam to be mined by the Coal Ridge No. 1 operation is in the Williams Fork Formation within the Bowie member. Coal seams in the Bowie member are the most continuous of any of the Mesaverde coals. Their cumulative thickness is 33 to 54 feet and average 41 feet. At the top of this J'