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<br />The New Horizon North (NHN) Mine is located three miles northwest of the town of Nucla, in <br />western Montrose County, Colorado. The mine area lies within the southeastern section of the <br />Colorado Plateau Physiographic Province. The region is characterized by broad, fairly smooth- <br />surfaced sandstone plateaus and mesas, with gently dipping slopes dissected by deep canyons. <br />Elevations at the site range from 5,790 feet (MSL) in the northeast corner of the permit area to <br />5,540 feet (MSL) at the southern end of the equipment corridor, for a total topographic relief of <br />250 feet. Permit Map 2.04.5-1 illustrates the topography and geology of the area surrounding the <br />area to be mined. <br /> <br />With respect to regional coal resources, this area lies within the Nucla-Naturita Coal Field of the <br />San Juan River Coal Basin. The coal is found in late Cretaceous sediments. The youngest <br />Cretaceous rocks in the area are Mancos shale, a dark gray marine shale, forming the isolated <br />hilltops south of the town of Nucla. The Mancos shale overlies the Dakota sandstone. Two <br />hundred feet of Dakota sandstone outcrops extensively along the axis of the Nucla syncline. <br />This formation consists of a yellowish-gray, fissile sandstone and conglomeratic sandstone <br />interbedded with dark gray shale and coal. There are two coal seams within 100 feet of the base <br />of the Dakota. The lower Cretaceous unit in the area, the Burro Canyon Formation, is separated <br />from the Dakota by an unconformity. The Burro Canyon is comprised of white, gray and light <br />brown sandstones and conglomerates interbedded with green and purplish shales, siltstones, <br />mudstones and thin beds of limestone. This formation has a maximum thickness of 200 feet and <br />outcrops on rims of canyons west and northwest of the mine. The Burro Canyon formation is <br />difficult to differentiate from the Dakota in this area and is commonly considered <br />hydrogeologically similar. The Dakota Sandstone unit covers most of the surface in the area; <br />however, in deeper canyons to the west along the lower reaches of Tuttle Draw, Coal Canyon, <br />and the San Miguel River, the Jurassic Morrison Formation and older strata are exposed. The <br />Morrison Formation is composed of 250 feet to 600 feet of varicolored siltstones and mudstones <br />with beds of limestone and sandstone. <br /> <br />Structurally, the NHN Mine site is located near the axis of the northwest-trending Nucla <br />Syncline. This syncline is a shallow, broad, structurally simple fold bounded by gently dipping <br />flanks. The syncline rests between the Uncompahgre Uplift to the northeast and the Paradox <br />Valley Anticline to the southwest. Strata within the permit area strike at N 26˚ W, and dip at <br />approximately 2˚ westward. WFC proposes to mine the Lower Dakota (LDx) Seam, and the <br />upper seam when it is available and of sufficient quality. Overburden thicknesses range from <br />approximately 10 feet, near “Meehan Draw” to slightly over 90 feet at the former Nucla Mine <br />highwall that will be exposed when mining begins. A general columnar geologic section is <br />provided in the permit application with Figure 2.04.6-1. <br /> <br />Ground Water – Sections 2.04.5 and 2.04.7 of the permit <br /> <br />Topography, lithology, and structural trends each play a principal role in controlling the quality, <br />quantity and flow characteristics of the regional ground water regime in the direct vicinity of <br />WFC's New Horizon North (NHN) Mine Area. The geology of this region is complex. <br />Consequently, the ground water system is difficult to interpret. Understanding the affect the <br />NHN Mine may have on the local and regional ground water supply relies on understanding the <br /> <br /> <br /> <br />7 <br /> <br />