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river valleys, and rolling upland parks. The proposed core holes are situated in the rugged hilly area along the Foidal Creek and Middle Creek drainages east of Twentymile Park. The proposed seismic lines cross through the rolling terrain of Twentymile Park. The area is drained by a dendritic pattern of seasonal drainages that flow into Fish Creek, Foidal Creek and Middle Creek. All of these drainages are tributaries of Trout Creek which flows north to the Yampa River. In Twentymile Park, a dendritic pattern of seasonal drainages flow generally eastward into Fish Creek. Deposition in the project area is largely alluvial with source proveniences in the Flat Tops and Williams Fork Mountains to the south. Dark brown silts and sandy silts several meters thick have accumulated in the Fish Creek drainage bottoms which were observed to contain multiple buried soils. The deposits on the tops and upper slopes of the low ridges in Twentymile Park are thin and consist of a light brown silty loam. Well rounded quartzite cobbles and a few cobbles and small boulders of basalt litter the surface on the tops and upper slopes of the ridges. The cobbles of quartzite are likely sources of toolstone for the prehistoric inhabitants in the area. The rugged hilly areas surrounding Twentymile Park contains thick colluvial deposits on the steep slopes and in the drainage bottoms. Some alluvial deposits have also accumulated in the drainage bottoms as well and aeolian sand shadow deposits have accumulated on the leeward sides of topographic prominences. The project azea is situated at the west edge of a structural syncline underlain by Cretaceous age Lewis Shales and sandstones, coal beds and shales of the Williams Fork Formation. The eastern limb of a structural anticline borders Twentymile Park on the west and small uplifted blocks border it on the east (Tweto 1976). The tops of the high ridges, knobs and hills surrounding Twentymile Park are capped by the thick, light colored Twentymile sandstone. Outcroppings of the Twentymile sandstone in the area are the frequent locations of rock art panels and rockshelters (Pool 1995). The azea contains an abundance of diverse flora and fauna. Flora in the azea vary by elevation and topographic context. Stands of aspen trees and thick shrubs are found at the higher elevations on north facing slopes while sagebrush, grasses, and mixed fortis are found in the pazks and along drainages at the lower elevations and on south facing slopes. Vegetation cover throughout the project area was heavy (80-100%) with very limited ground visibility. Somewhat better ground visibility was found on ridgetops and in disturbed areas in Twentymile Park where the vegetation cover was somewhat less (50-70%). Fauna include a variety of lazge ungulates, black bear, coyote, fox, and several species of small and medium-sized mammals. Numerous avian species also inhabit the area including golden eagles and hawks. The area is presently used for agriculture and coal mining with several ranches and large surface and subsurface coal mines in the area. Large portions of Twentymile Park appear to have been mowed and/or plowed in the past and cattle grazing is ongoing. Reclaimed strip mined areas aze visible in the mountainous areas to the east of Twentymile Park. Several undocumented exploration drill sites are present throughout the area. The project area is rich in 2