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Complied with 3!14!1998. Description of the Environment The surface facilities of the mine were located on north-sloping fan terraces at the foot of a spectaculaz, steep hillside formed by steeply-dipping bedrock (the Grand Hogback). The lower terraces of the site, at elevation approximately 5,800 feet, are approximately 150 feet above the Colorado River, and are used as cropland (grass and alfalfa) and for grazing. The base of the steep slopes is used for grazing (sagebrush areas). Geoloev Rock strata dip ranges from 30 to 70 degrees to the west-southwest. Minor folds trending north-south to northwest-southeast occur throughout the region. However, there is little evidence of faulting along the Grand Hogback. The exposed mck 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 stratigraphy of the Mesaverde Group includes interbedded and lenticulaz 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, ofthe Iles Formation, and the upper three members belong to the Williams Fork Formation [see Figure 3.3-3 in the Permit Application Package (PAP)]. The Wheeler coal seam, which was planned to be mined at the Coal Ridge No. 1 Mine, 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. The Wasatch and Ohio Creek formations unconformably overlie the Mesaverde Group. These formations consist of red and buff shale, red sandstone, and red to gray conglomerate and form the ridge bluffs of the Grand Hogback. Quaternary unconsolidated sediments in the mine azea, as represented by surface features, fall into three geomorphic categories: 1) Alluvium: These Quaternary deposits include all sediments associated directly with the active portions of the various stream channels and alluvial fans. 2) Terraces: Sediments associated with the inactive portions of the stream channels, particularly those at much higher levels, have been categorized as Quaternary Terraces. 3) Colluvium: Colluvial deposits aze considered to be loose, heterogeneous rock masses 10 June 1, 2006