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L <br /> The mine is located within the southeast portion of the Colorado Plateau. The region is <br /> characterized by broad, fairly smooth surfaced plateaus and mesas with gently dipping slopes <br /> dissected by steep canyons. Surface elevations at the New Horizon Mine 2 area range from <br /> a high of 5,760 feet (MSL) in the northeast part to a low of 5,642 feet in the southeast part <br /> along Calamity Draw for a total relief of about 118 feet. <br /> Climate <br /> The regional climate of the New Horizon area is typical of intermountain regions. It is <br /> characterized by cold winters, hot summers, low rainfall, and short growing seasons. The <br /> mine receives approximately 12 inches of precipitation in an average year. The majority of <br /> the precipitation falls between October and May. <br /> Regional Geology <br /> The New Horizon Mine 2 is located near the axis of the Nucla Syncline (San Miguel <br /> Syncline), a shallow, broad synclinal fold running northwesterly for 65 miles. No evidence <br /> of faults has been observed in drill holes at New Horizon Mine 2 area. The Nucla Syncline <br /> is 10 to 15 miles southwest of the major regional geologic feature of the area, the <br /> Uncompahgre uplift. The region lies in the Dolores River basin. The mines are located <br /> two to four miles northeast of the San Miguel River. Gently rolling terrain traverses the <br /> area and the mine 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 consist of Mancos shale, a dark grey <br /> marine shale, present only on isolated hilltops south of the town of Nucla. Two hundred <br /> feet of Dakota sandstone outcrops extensively along the axis of the Nucla syncline. This <br /> formation consists of a yellowish-gray, fissile sandstone and conglomeratic sandstone <br /> interbedded with dark grey shale and coal. There are two coal seams within 100 feet of the <br /> base of the Dakota. The lower Cretaceous unit in the area, the Burro Canyon Formation, <br /> is separated from the Dakota by an unconformity. The Burro Canyon is comprised of white, <br /> grey and light brown sandstones and conglomerates interbedded with green and purplish <br /> shales, siltstones, mudstones and thin beds of limestone. This formation has a maximum <br /> thickness of 200 feet and outcrops on rims of canyons west and northwest of the mine. This <br /> formation is difficult to differentiate from the Dakota in this area and is commonly <br /> considered hydrogeologically similar. The Jurassic Morrison Formation is composed of 250 <br /> feet to 600 feet of varicolored siltstones and mudstones with beds of limestone and <br /> sandstone. <br /> The New Horizon Mine 2 primarily produces coal from the Lower Dakota coal seam and <br /> will utilize the Upper Dakota coal seam when the seam is thick enough and of sufficient <br /> quality. The lower Dakota coal seam at New Horizon Mine 2 ranges in thickness from 4.2 <br /> feet to 6.9 feet and is 99 feet above the top of the Burro Canyon Formation. The coal dips <br /> 4.5° SW along a strike of N 45°W. <br /> 5 <br />