Laserfiche WebLink
Mayo and Associates, LC <br />• Formation escarpment, and on the east by the western flanks of Mount Gumrison. Total <br />topographic reliefwithin the study area exceeds 3,000 feet, ranging from approximately <br />6,000 feet along the North Fork of Gunnison River to greater than 9,000 fee[ along the flanks <br />of Mount Gunnison. The land surface in the lease area consists of deeply incised drainages <br />with moderately steep canyon walls capped by narrow mesas in the uppermost elevations. <br />Large mesas exist in the eastern portion of the lease in an area known as the West Flatiron. <br />The area is vegetated primarily by oak brush and other short, bushy, deciduous trees. In the <br />stream bottoms and on some steep north-facing slopes, [he land surface is vegetated with <br />aspen groves interspersed with conifer trees. Much of the land surface is covered with a [hick <br />veneer of soil. Exposures of bare rock at the surface are not common, except fur [he steepest <br />• ridges and the valley of the North Fork of the Gunnison River. The shales and sandstones <br />that make up the rock section in the area are, in many locations, unstable and landslides are <br />common, particularly along north facing slopes of the major stream drainages and on Jumbo <br />Mountain. <br />3.3 Geology <br />The West Elk Mine area is located in the southeast portion of the Piceance Basin, which is <br />one of several Laramide structural and depositional basins of the Colorado Plateau-Rocky <br />Momrtain foreland region. The rocks of the region consist predominantly of interbedded <br />sandstones, shales, and coal beds, which dip gently to the northeast. The main coal beds in <br />the region are located in [he Late Cretaceous Mesaverde Formation (Figure 3). <br />• <br />Characterization of Groundwater Systems ~n the Vicinity of the West Elk Mine, Somerset, Colorado <br />29 January 1999 <br />Page I 1 <br />