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III. Description of the Environment <br />A. General and Affected Area <br />The New Horizon Mine 1 permit block encompasses approximately 98.6 acres that have been <br />reclaimed. This area is commonly referred to as the Rice tract. Revegetation sampling was <br />initiated on this tract in 2006 and the initial results indicated that it would not achieve the Phase <br />III revegetation success standards. On June 20, 2012, the Mine 1 area was incorporated into the <br />New Horizon North Mine (Permit No. C-2010-089), which is also operated by ERMR. The <br />Division has not, as of this writing, received an application requesting removal of the Mine 1 <br />acreage from this permit, so the affected area is presently double -bonded. <br />The New Horizon Mine 2 permit block encompasses approximately 818.19 acres. Approximately <br />736.6 acres was disturbed for mining or related activities. The majority of this findings document <br />pertains to the Mine 2 area, since the activities at Mine 1 are documented in the New Horizon <br />North permit, C2010-089. <br />The topography is gently sloping with a few small ridges and swales. Most of the land surrounding <br />the permit area is agricultural and is used for irrigated and non -irrigated farmland that generally <br />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 northeast <br />of the San Miguel River. Gently rolling terrain traverses the area and the mine occupies a <br />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 shale, <br />comprising the isolated hilltops south of the town of Nucla. The Mancos shale overlies the Dakota <br />sandstone. Two hundred feet of Dakota sandstone outcrops extensively along the axis of the Nucla <br />syncline. This formation consists of a yellowish -gray, fissile sandstone and conglomeratic <br />sandstone interbedded with dark gray shale and coal. There are two coal seams within 100 feet of <br />the base of the Dakota. The lower Cretaceous unit in the area, the Burro Canyon Formation, is <br />separated from the Dakota by an unconformity. The Burro Canyon is comprised of white, gray <br />and light brown sandstones and conglomerates interbedded with green and purplish shales, <br />0 <br />