2003-01-27_GENERAL DOCUMENTS - C1981022

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tributary of the North Fork and provides both domestic and agricultural supplies of water. Bear Creek, Ells Creek and Sanbom Creek are intermittent streams. Coal Gulch, the unnamed drainage, A, B and C Gulches, Hawk's Nest Creek, Hoopla Gulch, Bazdine Canyon and Thompson Creek are all ephemeral drainages that flow to the North Fork. The North Fork River Basin contains a developed water supply providing agicultural water to the fruit-growing region of the North Fork Valley. The North Fork River enters the main stem of the Gunnison River approximately 30 miles southwest of the Somerset Mine. The drainage basin of the North Fork is mountainous, bounded to the west by the Raggeds, the Ruby Range, to the east by the Huntsman Ridge, to the South by the West Ells Mountains, and to the North by Grand Mesa. Elevations in the basin range from 13,058 feet atop Mt. Owen in the Ruby Range, to 5,100 feet at the confluence of the North Fork with the Gunnison River. The town of Somerset, Colorado, immediately adjacent to the Somerset Mine site, is at an elevation of 6,045 feet. Ground reconnaissance during 1978, 1979 and 1980 identified Ells No. 1 Spring as the only location with ground water surfacing within the original Somerset permit area, and this had a flow rate of less than one gallon per minute. It is concluded that there is no lazge ground water reservoir in the area. Western Slope Cazbon identified and monitored 11 springs within or adjacent to the Sanborn East Tract. Monitoring records aze available from 1983 through 1987. Somerset Mining Company, now Oxbow Mining, LLC, resumed monitoring these springs in July 1992. Springs 1 through 6 aze located along the north boundary of the Sanborn East Tract in the northern portion of Section 2. Springs 7 through 11 are located along the southern boundary of the new tract. The locations of the springs are shown on Map 2.04-M5. The topography of the region is characterized by steep canyons cut by the North Fork of the Gunnison River and its tributaries, with several remnant alluvial terraces above the valley of the North Fork. Proceeding downstream below Somerset, Colorado, the canyon widens. At Paonia, Colorado, the canyon has given way to a broad alluvial plain with interspersed remnant alluvial terraces. The coal to be mined is located in the Somerset Coal Field. The strata exposed in the Somerset Coal Field consist of the Mancos Shale and the coal-bearing Mesaverde Formation of Upper Cretaceous Age, and of the Ohio Creek Conglomerate, the Wasatch Formation and the Quartz Monzonite Porphyry of Early Tertiary Age. Coal is mined from the Mesaverde Formation, a 2,500 foot thick sequence of sedimentary strata overlain by the Ohio Creek Conglomerate and underlain by the Mancos Shale. The strata in the Sanborn Creek and Elk Creek Mines permit azea dip three to five degrees north-northeast within the permit area, but vanes locally. The Mesaverde Formation contains two coal bearing members. The Somerset Mine mined coal from the B-2 seam of the lower coal bearing (Bowie) member of the Mesaverde Formation. The Sanborn Creek and Sanbom Creek East additions to the mine will extract coal from the B and C seams of this member. The Lower Coal member ranges from 260 to 350 feet thick in the Somerset Coal Field and beazs three minable coal seams. This member consists of interbedded