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-8- 2. Description of the Environment The mine site is located at an elevation of approximately 5800 feet. Land use within the permit and adjacent areas is grazing and wildlife habitat. Grazing is generally confined to the lower-lying canyon bottom lands. The upland area consists of steep slopes and rugged topography and is primarily used by wildlife. Some irrigated agriculture is practiced in the East Salt Creek Valley which is adjacent to the permit area. Munger Canyon is located in the Roan Cliffs just north of Grand Valley. This area is northeast of the Garmesa Anticline and on the south flank of the Piceance basin. Local strata dip in the northeast into the Piceance basin at one to three degrees and strike north-northwest. No faults have been identified in the Munger Canyon mine plan area. The adjacent McClave Canyon t4ine (north of the proposed Munger Canyon Mine) is located within a graben structure which is bounded by two large, high angle displacement faults. The Mount Garfield Formation is the coal-bearing formation in the Book Cliffs Coal Field. The Mount Garfield Formation consists of fine-grained and medium grained sandstones and gray shales. The Sego Sandstone underlies the Mount Garfield Formation and the Hunter Formation overlies it. Included within the Hunter Formation are the massive cliff-forming sandstones which 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 Upper Carbonera and Cameo seams will be mined at the Munger Canyon Mine. No major bedrock aquifers of regional extent have been identified in the permit and adjacent area by the applicant. Drilling has indicated that the Cameo coal seam becomes increasingly saturated downdip from it's outcrop in Munger Canyon. The Cameo seam subcrops below the East Salt Creek alluvium. This indicates that East Salt Creek, several miles from the mine, is the recharge source for the Cameo coal seam. Some local lenticular strata of limited extent have been identified above the Cameo seam which contain perched ground water. Underground mining activities at the Munger Canyon Mine will be updip and away from the saturated zone in the Cameo seam (see Figure 4.4-1 of Volume III of the application). Alluvial ground water exists within the East Salt Creek alluvium. The East Salt Creek Valley contains an intermittent stream channel. Munger Canyon contains an ephemeral channel which is tributary to East Salt Creek. Ground water in the alluvium and colluvium of Munger Canyon is at depths greater than 40 feet and thus is too deep to support subirrigation of crops. Ephemeral tributaries to Munger Canyon will be undermined during the 5-year permit period and life-of-mine. Two ephemeral tributaries to Big Salt Wash; Buniger and Stove Canyons, will also be undermined during the 5-year permit period and life-of-mine.