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The topography is gently sloping with a few small ridges and swales. Most of the land <br />surrounding the permit area is agricultural and is used for irrigated and non - irrigated farmland <br />that generally produces alfalfa or pasture grasses. <br />The mine is located within the southeastern portion of the Colorado Plateau. The region is <br />characterized by broad and fairly smooth surfaced plateaus and mesas with gently dipping slopes <br />which are dissected by steep canyons. Surface elevations at the New Horizon Mine 2 area range <br />from a high of 5,795 feet (MSL) in the northeast part to a low of 5,555 feet in the northwest part <br />along Tuttle Draw for a total relief of about 240 feet. <br />B. Geology and Topography <br />The New Horizon Mine is located near the axis of the Nucla Syncline (San Miguel Syncline), a <br />shallow, broad synclinal fold running northwesterly for a length of 65 miles. No evidence of <br />faulting was observed in drill holes at New Horizon Mine 2 area. The Nucla Syncline is 10 to 15 <br />miles southwest of the major regional geologic feature of the area, the Uncompahgre uplift. The <br />region lies in the Dolores River basin. The mine is located between two and three miles <br />northeast of the San Miguel River. Gently rolling terrain traverses the area and the mine <br />occupies a predominantly southwestern exposure. <br />The mine is located in the Nucla - Naturita coal field. The coal is found in late Cretaceous <br />sediments. The youngest Cretaceous rocks in the area are Mancos shale, a dark gray marine <br />shale, comprising the isolated hilltops south of the town of Nucla. The Mancos shale overlies the <br />Dakota sandstone. Two hundred feet of Dakota sandstone outcrops extensively along the axis of <br />the Nucla syncline. This formation consists of a yellowish -gray, fissile sandstone and <br />conglomeratic sandstone interbedded with dark gray shale and coal. There are two coal seams <br />within 100 feet of the base of the Dakota. The lower Cretaceous unit in the area, the Burro <br />Canyon Formation, is separated from the Dakota by an unconformity. The Burro Canyon is <br />comprised of white, gray and light brown sandstones and conglomerates interbedded with green <br />and purplish shales, siltstones, mudstones and thin beds of limestone. This formation has a <br />maximum thickness of 200 feet and outcrops on rims of canyons west and northwest of the mine. <br />The Burro Canyon formation is difficult to differentiate from the Dakota in this area and is <br />commonly considered hydrogeologically similar. The Jurassic Morrison Formation below is <br />composed of 250 feet to 600 feet of varicolored siltstones and mudstones with beds of limestone <br />and sandstone. <br />The New Horizon Mine 1 produced coal from both the upper and lower Dakota coal seams. The <br />upper Dakota coal seam ranged in thickness from 1.6 feet to 3.3 feet and was separated from the <br />lower Dakota seam by 7 to 11 feet of interbedded sandstone and shale. The lower Dakota seam <br />varies in thickness from 5.9 feet to 7.9 feet. The base of the lower Dakota coal is 83 feet above <br />the top of the Burro Canyon Formation. The coal dips 10 to 20 southwest and strikes N 25 0W to <br />N 45° W. <br />The New Horizon Mine 2 primarily produces coal from the Lower Dakota coal seam and utilizes <br />the Upper Dakota coal seam when the seam is thick enough and of sufficient quality. The lower <br />10 <br />