GENERAL49556 - Laserfiche WebLink

Home Browse Search

McClane Canyon is located in the Book Cliffs area just north of the Grand Valley. This area is northeast of the Garmesa Anticline and on the southern flank of the Piceance Basin. Local strata strike north-northwestward and dip to the northeast into the Piceance Basin between 2 and 3 degrees. The surface geology of the permit area is made uo of the Mesa Verde GroUD of Upper Cretaceous Age, the Wasatch Formation of Lower Tertiary Age, and alluvium and colluvium of Quaternary Age. The Mount Garfield Formation consists of fine grained to medium grained sandstones, gray shales, and coal bearing zones. 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 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 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 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 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. Saturation of the Cameo seam occurs at about 5580 ft. elevation. 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 alluvial valley floor downstream from McClane Canyon are utilized for irrigated cropland (alfalfa). McClane Canyon contains an ephemeral channel which is tributary to East Salt Creek. The proposed surface disturbance for the McClane Canyon Mine is entirely within the McClane Canyon drainage basin with the exception of the sediment pond, lower portion of the access road, and the proposed haul road, which are situated on the East Salt Creek alluvial valley floor. -4-