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Elevation on the mine property ranges from about 6,500 feet in the valley where <br />Engleville Gulch flows out of the permit area to 6.900 feet in the southeast comer of the <br />property. The permit area lies within the Engleville Gulch watershed, whose resident <br />stream is an ephemeral tributary of the Purgatoire River. Engleville Gulch headwaters <br />are on the northern flank of Fisher's Peak to the southeast of the mine permit area The <br />climate is semi-arid with annual precipitation of 13" to 15" <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. Actual acreage <br />disturbed was 12.62 acres. Coal was mined at the Rimrock Mine by strip mining <br />methods. Mining was conducted in the Engleville Seam that splits into the upper and <br />lower Starkville seams in the nearby Raton Creek Mines. The Engleville seam occurs <br />near the middle of the Vermejo Formation. a 55-foot thick section characterized by <br />alternating beds of shale, siltstone. sandstone, and coal. The coal seam averages <br />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. These <br />soils are 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 PirSon-Juniper predominating amidst grassland. The dominant grasses <br />on the site are blue grams (Bouteloua rg acilis) and western wheatgrass (Agropvron <br />smithii . The community also consists of lesser quantities of other grasses, fortis, and <br />cactus. Pirlon pine (Pinus edulis) and gambel oak ( uercus ambeGi occur in small <br />stands. <br />Pre-mining land use in the 38-acre permit area was primarily pasture and rangeland <br />Pre-law coal mining began in the permit area in 1893. Incidental use of the permit area <br />by wildlife has been noted. Species observed in the area include mule deer, Merriam's <br />turkey. and various small game <br />Under the original permit, it was anticipated that an average of 30,000 tons of coal <br />would be mined annually with a total of 150,000 tons mined over the five-year period. <br />Prior to overburden stripping, topsoil was to have been removed from the pit area and <br />stored in accordance with the Division's requirements. Each mine working area was <br />held to about 1.5 acres in size and was to be completely restored and re-vegetated <br />(seeded) before stripping in another area began. No more than 1.5 acres was to have <br />been exposed at one time The initial boxcut overburden material was to have been <br />used to reclaim the last 1.5 acre stripped area, providing for only temporary stockpiling <br />of overburden material from the initial cut. The remaining disturbances, comprised of a <br />sediment pond and one haul road, were not to be reclaimed, but were proposed to be <br />left in stable condition at the request of the landowner <br />Sediment and drainage control, when necessary. was accomplished by diversion <br />