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<br />approximately 2 degrees to the west-southwest. There are three water-bearing lithologic <br />units identified in the permit area. These are in descending order, the Raton Formation, <br />Vermejo Formation, and the Trinidad Sandstone. The Trinidad Sandstone is the only <br />aquifer of regional significance in the area. <br />One coal seam, the Engleville seam, was planned to be mined under the proposed plan. <br />The Engleville seam occurs near the middle of the Vermejo Formation, a 55-foot thick <br />section characterized by alternating beds of shale, siltstone, sandstone, and coal. The <br />coal seam averages about 10 feet in thickness throughout the mine site. <br />Soils on the side slopes of the mine site are shallow, being derived from parent <br />sandstone and shale layers that outcrop in the area. Soils in the permit and adjacent <br />areas are mixtures of two major units, the Ayon and Capulin loam soil units. This type of <br />soil is classified as class IV, a category of soils that requires careful management <br />because of severe limitations that restrict land use options. <br />The primary vegetative community in the permit area consists of a warm season/cool <br />season grassland with scattered trees and shrubs. The adjacent areas have similar <br />vegetation, with Pinon-Juniper predominating amidst grassland. The dominant grasses <br />on the site are blue grams (Bouteloua racilis) and western wheatgrass (Aoropyron <br />smithii). The community also consists of lesser quantities of other grasses, fortis, and <br />cactus. Pinon pine (Pinus edulis) and gambel oak (Quercus ag mbelii) occur in small <br />stands. <br />Pre-mining land use in the 38-acre permit area is primarily pasture and rangeland. <br />Mining began in the permit area in 1893 and has been sporadic since that time. <br />Incidental use of the permit area by wildlife has been noted. Species observed in the <br />area include mule deer, Merriam's turkey, and various small game. Consultation with <br />the Colorado Division of Wildlife indicate other species likely in the area include black <br />bear, mountain lion, and elk. The closest identified eagle nest was located <br />approximately four miles east and 1 mile south of the permit area, as verified in a letter <br />from Mr. James L. Aragon of the Colorado Division of Wildlife, dated August 6, 1987. <br />There are no known threatened or endangered species identified within or in close <br />proximity to the permit area. <br />Description of the Operation and Reclamation Plans <br />The Rimrock Mine permit area is 38.0 acres. Acreage previously approved to be <br />disturbed during the permit term was not to exceed 19.6 acres. Coal was mined at the <br />Rimrock Mine by strip mining methods. Mining was conducted in the Engleville Seam <br />that splits into the upper and lower Starkville seams in the nearby Raton Creek Mines. <br />Under the original permit, it was anticipated that an average of 30,000 tons of coal would <br />be mined annually with a total of 150,000 tons mined over the five-year period. Prior to <br />overburden stripping, topsoil was to have been removed from the pit area and stored in <br />4 <br />