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The New Horizon Mine 2 area will encompass approximately 808.3 acres with the approval of PR- <br />OS. Approximately 653.5 acres will be disturbed due to mining or related activities at Mine 2. The <br />majority of this findings document pertains to the Mine 2 area since the activities at Mine 1 have <br />ceased with the exception of water monitoring. <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 primarily for irrigated and non-irrigated farmland which <br />produces alfalfa and pasture grasses. <br />Both mines are 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 azea range from a high <br />of 5,795 feet (MSL) in the northeast part to a low of 5,560 feet in the southeast part along Tuttle <br />Draw for a total relief of about 235 feet. <br />Climate <br />The regional climate of the New Horizon azea is typical of intermountain regions. It is chazacterized <br />by cold winters, hot summers, low rainfall, and short growing seasons. The mine receives <br />approximately 12 inches of precipitation in an average year. The majority of the precipitation falls <br />between October and May. <br />Regional Geology <br />The New Horizon Mines aze located neaz the axis of the Nucla Syncline (San Miguel Syncline), a <br />shallow, broad synclinal fold running northwesterly for 65 tniles. No evidence of faults has been <br />observed in drill holes at New Horizon Mine 2 azea. The Nucla Syncline is 10 to 15 miles southwest <br />of the major regional geologic feature of the azea, the Uncompahgre uplift. The region lies in the <br />Dolores River basin. The mines aze located two to four miles northeast of the San Miguel River. <br />Gently rolling terrain traverses the area and [he mine occupies a predominantly southwestern <br />exposure. <br />The mines are located in the Nucla-Naturita coal field. The coal is found in late Cretaceous <br />sediments. The youngest Cretaceous rocks in the azea consist of Mancos shale, a dazk grey marine <br />shale, present only on isolated hilltops south of the town of Nucla. Two hundred feet of Dakota <br />sandstone outcrops extensively along the axis of the Nucla syncline. This formation consists of a <br />yellowish-gray, fissile sandstone and conglomeratic sandstone interbedded with dark grey shale and <br />coal. There aze two coal seams within 100 feet of the base of the Dakota. The lower Cretaceous unit <br />in the area, the Burro Canyon Formation, is sepazated from the Dakota by an unconformity. The <br />Burro Canyon is comprised of white, grey and light brown sandstones and conglomerates <br />interbedded with green and purplish shales, siltstones, mudstones and thin beds of limestone. This <br />formation has a maximum thickness of 200 feet and outcrops on rites of canyons west and northwest <br />of the mine. This formation is difficult to differentiate from the Dakota in this azea and is commonly <br />considered hydrogeologically sirnilaz. The Jurassic Morrison Formation is composed of 250 feet to <br />600 feet of varicolored siltstones and mudstones with beds of limestone and sandstone. <br />