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• In the Hesperus area, there are 2 coal seams more than 3 feet thick. The upper, the A Coal Seam, is immediately below the Cliff House Sandstone. In outcrops in Hay Gulch, this coal seam is fairly consistent and averages about 5 to 6 feet. The A Coal Seam is mined extensively in the Hesperus area and is probably the most important bed of the area. It is thickest along the walls of Hay Gulch. The next lower bed, which is called the B Coal Seam, lies below the A Coal Seam, and above the massive sandstone that caps the Point Lookout Sandstone. It ranges in thickness from 3 to 5 feet. Cliff House Sandstone. The upper part of the Mesaverde Formation lying above the Menefee Formation is referred to as the Cliff House Sandstone. It consists of interbedded and interlensed sandstone and shale of varying thicknesses. The general character of these barren upper beds • is the same as in the Menefee Formation, except that the sandstone beds are more lenticular and the shale zones are essentially barren of coal. The thickness of the Cliff House Sandstone varies greatly owing to the post-Mesa Uerde erosion, but is originally much in excess of 400 feet. Field evidence suggests a northward truncation of the entire Mesa Verde Formation by post-Cretaceous tilting and subsequent erosion. Structure The structural geology of the permit and adjacent area appears to be quite simple. The sedimentary strata of the Mesaverde Formation are relatively flat line with an average regional dip of 2 to 3 degrees to the south-southwest. Although limited local dips of up to 5 degrees can be found. No faults have been mapped within the permit area or adjacent area. The generalized geologic structural and stratigraphic setting of the area is shown on the Regional Geology Map (Map 5), and Figure 2, Generalized stratigraphic Column. The site specific stratigraphy is • found on the Regional Geology Map (Map 5). 2.04-10