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C Formation which contains massive cliff-forming sandstones that outcrop along the canyon walls of East Salt Creek. The Mount Garfield Formation contains four coal zones;the Loma,Carbonera,Cameo,and Palisade zones. The Cameo seam is mined at the McClane Canyon Mine. The occurrence of ground water within and adjacent to the McClane Canyon Mine permit area is controlled primarily by the combination of local topography, stratigraphy and geologic structure. Drilling has indicated that the Cameo seam becomes increasingly saturated downdip (northeast) from its outcrop along the side slopes of the East Salt Creek drainage basin. This is depicted on Figure 4.2-3 of Volume II of the permit application. As can be seen on the figure,the saturated zone extends downdip towards the northeast along a northwest-southeast trending line. The outcrop line of the coal as well as the East Salt Creek drainage, run roughly north-south in the vicinity of the permit area. Recharge to the Cameo coal seam occurs in an area where the coal seam subcrops in the East Salt Creek alluvium approximately two miles north of the McClane Canyon Mine permit area. The subcrop of the coal seam along East Salt Creek was created as the stream gradually cut through the sedimentary strata to the point where the stream channel intersected the Cameo coal seam. The underground workings of the McClane Canyon Mine extend roughly eastward into the Cameo seam from a point where the coal seam outcrops in McClane Canyon. McClane Canyon is a small tributary canyon to the East Salt Creek drainage. In addition to the saturated portions of the Cameo seam, some local lenticular strata of limited extent situated above the Cameo seam have been found to contain ground water perched within the strata. Saturation of the Cameo seam occurs at about 5580 ft.elevation. East Salt Creek is an intermittent stream tributary to the Colorado River. The East Salt Creek Valley has been designated as an alluvial valley floor(AVF), with both undeveloped rangeland and irrigated hayland mapped on the AVF in the vicinity of the mine. Existing and proposed surface disturbances associated with the mine are located in the McClane Canyon drainage basin upstream from the AVF boundary, with the exception of office trailer facilities and the lower portion of the access road, which are situated within the boundaries of the AVF. The climate in the region is semi-arid. Prevailing winds at or near ground level at the mine are dictated by the orientation of the deeply incised McClane Canyon. The annual average precipitation within the permit area increases with elevation from approximately 10 inches along East Salt Creek, up to 15" on the ridges above 7000 feet. Soils in the permit area are well drained to excessively well drained and have formed in alluvial or colluvial sediments. Soils are deepest in the valley bottoms and become shallower along the canyon sideslopes where they intersperse with bare rock. Most of the soils are rated fair to good as sources of topsoil for reclamation. Limitations exist for subsoils in the alluvial deposits along valley bottoms due to high sodium content. Vegetation types within and adjacent to the permit area are broadly classified as lower montane. Three primary vegetation types occur in the permit and adjacent area. A greasewood shrubland type occupies the flat terrain along the East Salt Creek drainage where soils are deep, well drained and often very sodic and moderately saline. Shadscale shrubland borders the greasewood shrubland along the dry,steep, south facing slopes in the shallower soils which are interspersed with rock outcrops. Juniper woodland is found along the ridge tops and steep north and west facing slopes of shallow soils and rock outcrops. These vegetation types are common to western Colorado and Utah. Current and historical land use within the permit area is livestock grazing and wildlife habitat. Cattle are run seasonally within the rangelands and grazeable woodlands. 7