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McClane Canyon is located in the Roan Cliffs area just north of Grand Valley. This area is northeast of the Garmess Anticline and on the southern flank of the Piceance Basin. Local strata strike north-northwestward and dip to the northeast into the Piceance Basin at approximately 2 degrees. The coal to be mined is within a graben which is bounded by two high-angle faults. The Mount Garfield Formation is the coal bearing formation in the Book Cliffs Coal Field. The Mount Garfield Formation consists of the fine grained and medium grained sandstones and gray shales. The Sego Sandstone underlies the Mount Garfield Formation. Overlying the Mount Garfield Formation is the Hunter 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 will be 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 coal 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 anorthwest-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 channel gradually cut through the sedimentary strata to the point where the stream channel intersected the Cameo coal seam on its way southward to the Colorado River. 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. Boreholes drilled below the Cameo seam were dry to a depth of 200 feet, indicating that saturated sandstone strata are approximately 210 feet below the Cameo seam. Alluvial ground water exists within the East Salt Creek alluvial valley floor. The East Salt Creek Valley contains an intermittent stream channel which is named East Salt Creek. No other alluvial valley floors have been identified within or adjacent to the permit area. A majority of the East Salt Creek alluvial valley floor is used for grazing land along with the adjacent upland areas. Portions of the AVF downstream from McClane Canyon are utilized for irrigated cropland (alfalfa). -2-