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• floors is presented in Tabs 7 and 16 of this PAP. The terrain is characterized by barren and sparsely brush covered southwestward facing cliffs where the more resistant sandstone outcrops end broad west- and northeast-facing moderately sloping sideslope benches and ridges that are deeply ineised. The long sloping landiorms of these areas roughly coincide with the strike and dip of the underlying bedrock. Roundetl shale knobs, ridges, and benches ere common in the west central end northern third of the mine site area and along the northern haul road. Deeply incised long, north-south trending drainages surrounded by very steep sitleslopes and escarpments bisect the central portion of the study area. Shorter, deeply incised northwest southeast trentli ng drainages dissect steeply sloping sandstone bedrock controlled topography in the southwest, northwest, and eastern portions of the study area. stratieraohv. The study area is in an area of high relief, having eroded in Cretaceous sedimentary rocks (Bass et al., 1955). The oldest formation that outcrops within [he Yoast permit area is the Iles Formation of the Mesave rde Group. The Iles Formation of late Cretaceous age outcrops along the southwestern end south easternmost boundary of the permit area. It is capped by the Trout Creek sandstone member, a fine-grained, • glauconitic sandstone interbedded with carbonaceous shale stringers. The Trout Creek sandstone is approximately 100 feet in thickness. The Trout Creek sandstone was deposited in a surf zone end near shore environment (Gaffke, 1979). The rocks underlying the Trout Creek sandstone consist of alternating beds of shales, sandstones, end thin coals. The coal beds are part of the lower coal group of the Mesaverde Group end range in thickness from epproxime rely 0.5 feet [0 2.0 fee[, ih ese underlying rocks outcrop immediately to the east of the Trout Creek sandstone outcrop. The Williams Fork Formation overlies the Trout Creek sandstone and outcrops throughout most of the mine area. The Lowermost unit of the 4illiams Fork Formation contains the coal beds that ere of interest et the Yoest Mine site. These coal beds are part of the middle coal group of the Mesaverde Group; the Wolf Creek coal is the lowest coal bed in the middle coal group (Figure 2). The Wolf Creek bed, which outcrops in the southeastern portion of the permit area and also south of the permit area, is typically [2 to 18 feet Shirk (Table 1) and is underlain by fine-grained sandstones, shales, mudstones, and thin coals (Gaffke, 1979). The Wolf Creek coal formed from peat deposited in a swamp • environment. Above the upper Yolf Creek coal bed lies about 150 [0 215 feet of sandstones, shales, siltstones, end thin coals. This interval of strata, although 7