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The proposed lease area is characterized by hilly plateau tops • cut by one ephemeral drainage. The elevation ranges from about 7,200 to 7,600 feet. The geologic formations outcropping in the area are the Cliff House Formation of the Cretaceous Mesa Verde Group and the overlying Quaternary alluvial deposits. The coal proposed for mining is coal bed 1 in the Menefee Formation which outcrops about 1~ miles north of the proposed lease area in the Hay Gulch drainage. No quantitative data exists for subsidence on the proposed lease area; however, the surface effects of subsidence have been recorded on Federal lease P-058300 approximately one mile northeast of the proposed lease area. The overburden thickness consistently ranges from 300 to. 400 feet above coal bed 1 throughout the area of the existing leases as well as in the proposed lease area. Subsidence is directly affected by the thickness of the coal seam mined (4 to 6 feet), the i ' overburden thickness, and overburden composition. There are no active faults adjacent to or on the proposed lease area (Zapp, 1949). DIo other geologic hazards are known to exist. No known fossils of significance have been found on or near the proposed lease area. The Mesa Verde Group yields sparse faunas of both marine and non-marine elements. No study exists with specific reference to the botanical fossils • related to the Menefee coals nor on the non-marine invertebrates on the associated units (Fischer, 1981). WATER The topographic surface of this area lies within the mid- section of the Pine Gulch drainage basin. The watershed is steep-sided (with slopes greater than 50$), has intermittent stream flow, and has a dendritic drainage pattern. The 100- year stream flow rate of Pine Gulch is 120 cfs., with an assumed velocity of 4-5 ft/sec. Flow rate was calculated from "Manual For Estimating Flood Characteristics of Natural Flow Streams in Colorado", Colorado Water Conservation Board, 1976. The proposed lease area is not in a major ground water recharge area. Because mining activity in coal bed 1 will be occurring approximately 40 feet above the piezometric surface, which is static water level, there is no indication that the aquifer will be affected by mining operations. VEGETATION The general area consists primarily of pasture and mountain shrub type vegetation along with pinon-juniper. The most prominent shrubs include Gambel oak (Ouercus Qambelii), Mountain mahogany (Cercocarpus montanus), and Utah 7