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-6- General Description of the Existing Environment The proposed operation is located in southwestern Colorado approximately 22 miles southwest of Pagosa Springs (Figure 1). Elevation of the area is approximately 6,400 feet. The proposed permit area lies in the upper rim of the San Juan Basin. The San Juan Basin is an asymmetric structural basin in northwestern New Mexico and southwestern Colorado. The surficial geology of the area consists of sedimentary rocks of marine and non-marine origin. Coal seams to be mined are in the lower Fruitland Formation. This formation is composed of interbedded sandstone, siltstone, shale, carbonaceous shales, and coal. Three coal seams of economic importance are found in this formation. Mining operations will remove the two upper seams. Ground water occurs in the sandstones of the Fruitland Formation, the Pictured Cliffs Formation, and in the alluvium associated with Stollsteimer Creek. The permit and adjacent areas of the mine are located within the Stollsteimer Creek Drainage Basin, which is tributary to the Piedra River. Deep Creek is the major ephemeral tributary draining the Permit Revision No. 2 area. The yearly amount of precipitation received at the mine site can be expected to range from 15" to 20". Rainfall accounts for 15 to 45% of the precipitation, with the majority occurring during the early summer/spring (May) and during late summer (August and September). Mean annual temperatures range between 45°F and 48°F. Maximum mean temperatures occur between May and September and average 73oF. The average minimum mean temperature during the same period is 43°F. Frost-free days range from 75 to 115 days. Wind direction is predominantly from the southwest. Soil types within the proposed permit area include the following mapping units; Carracas variant - Peney variant, Celacy variant loam, Nunn variant loam, and a paralithic clay shale - sandstone - carbonaceous shale - rock outcrop complex. The paralithic material is unsuitable for reclamation purposes, all other mapped soil units have suitable topsoil material with recommended stripping depths ranging from 14 to 72 inches. The Deep Creek area of Permit Revision No. 2 contains three vegetative communities; mixed brush-conifer, sparse pinyon-juniper, and riparian. The riparian community is found immediately adjacent to the Deep Creek drainage and is distinguished by species requiring mesic conditions; cottonwood trees and a variety of fortis and grasses. The mixed brush-conifer type occurs on the colluvial toe slopes above the Deep Creek drainage and is dominated by Gambels oak, ponderosa pine, yellow sweetclover, and b]ue grams. The sparse pinyon-juniper type occurs on the steep and south facing slopes above the mixed brush-confier type. The pinyon-juniper type is dominated by pinyon pine, Gambels oak, mountain mahogany, and bitterbrush.