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The North Fork is a highly developed water supply which provides agricultural water to the fruit-growing region of the North Fork Valley. The North Fork enters the main stem of the Gunnison River approximately 30 miles southwest of the Sanborn Creek 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 Elk 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 Sanborn Creek Mine site, is at an elevation of 6,045 feet. Ground reconnaissance during 1978, 1979 and 1980 identified Elk No. 1 Spring as the one location with ground water surfacing within the original Somerset permit area, with a flow rate of less than one gallon per minute. It is concluded that there is no significant shallow ground water reserve in the area. Western Slope Carbon identified and monitored 11 springs within or adjacent to the Sanborn East Tract. Monitoring records are available from 1983 through 1987. Somerset Mining Company resumed monitoring these springs in July 2992. Springs 1 through 6 are located along the north boundary of the new 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 drawing E8-3286. The topography of the region is characterized by steep canyons cut by the North Fork 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, 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 Wasatch Formation and underlain by the Mancos Shale. The strata in the Somerset Permit area dip three to five degrees north-northeast. 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 Sanborn 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 bears three minable coal seams. This member consists of interbedded and lenticular sandstones, siltstones and coals, and is overlain by a massive sandstone 25 to 225 feet thick which lies directly on the C seam and marks the bottom of the upper coal member. Sanborn Creek Mine 7 Permit Revision No. 3