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-1- The proposed refuse disposal area is underlain by the Poison Canyon and Raton Formations with surficial colluvial deposits. The soils are moderately deep to shallow, depending on the slope, and consist of channery silty clay loam. The vegetative communities consist of conifer-shrub and oak shrub. The region is characterized by a semiarid climate. The prevailing wind is from the southwest and average annual precipitation is 16.92 inches. The length of the growing season in the area varies from 90 to 110 days. Vegetative communities in the area of the mine can be separated into two physiognomic types; the low grassland and riparian communities along the valley bottom containing the Purgatoire River, and forest communities dominating the slopes of the river valley. Communities on the north facing slope and the river valley were inventoried and found to contain four distinct vegetative communities at the New Elk 14ine area; a Ponderosa Pine-Douglas fir oak community, a Ponderosa pine-oak community, a grassland community, and a riparian willow carr community. The Ponderosa pine-Douglas fir-oak community is found on the north facing slope above the mine facilities at elevations above 7,600 feet. The overstory consists of mature Ponderosa pine and Douglas fir with interspersed Pinon pine and Rocky Mountain juniper. The dominant shrub species is Gambel's oak. Cover is relatively sparse (12%) and productivity is low (63 lb/acre). The Ponderosa pine-oak community occurs on the north facing slopes above 1,500 feet on the eastern two-thirds of the permit area. Pure Ponderosa pine stands are interspersed with Gambel's oak, Pinon pine, and Rocky Mountain juniper. Cover is low (4%) as is productivity (44 lb/acre). The grassland community was inventoried at the Golden Eagle Mine, on a plateau above the river at 7,200 feet elevation, since no undisturbed grassland communities could be found at the New Elk Mine. Dominant species were blue grams, and western wheatgrass with many minor graminoids and fortis. Sage and snakeweed were the dominant shrubs. Cover was moderate (18%) as was productivity (560 lb/acre). The willow carr riparian community is located in the Purgatoire River drainage at an elevation of 7,400 feet at the New Elk Mine. The dominant species was willow with a diverse graminoid and forb understory. Cover is high (43%) as is productivity (2,140 lb/acre). Soils in the area range from very shallow on the steep side slopes to deep, well drained looms with a dark colored surface layer found in the valley bottom along the Purgatoire River.