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ranges from a low of approximately 6,130 feet in the Big Bottom area to a high of about 7,400 feet in the Williams Fork Mountains. The entire operation is located in Moffat County, Colorado. The permit surface area covers 6,363 acres, including 375 acre:a of federal owner- ship, 1,979 acres of state land, and 4,009 of private property. Life-of-mine minerals ownership of coal to be mined includes 512 acres of federal coal, 1,312 acres of state coal, and 350 acres of private coal. The mineral acreages do not include the old workings of the No. 5 and 9 Mines. The permit area is shown by Findings Figure 2. The USGS 7.5 minute Quadrangle maps of Round Bottom and Castor Gulch, Colorado, show the areas covered by this permit. Geology The axis of the Williams Fork anticline passes through the western edge of the proposed permit area (Findings Figure 3). The Williams Fork anticline is asymmetric, with its steepest dip on the west flank where it dips into the Round Bottom syncline. The east limb dips into the Big Bottom syncline. The orienta- tion of the fold axis is approximately NNW. Several faults have been identified within the permit area. Geologic formations within the vicinity of the mine are, in ascending order, the Marcos Shale, the Iles and Williams Fork Formations of the Mesaverde Group, and the Lewis Shale (See Findings Figure 4). These strata were all deposited in the late Cretaceous Period. Generally, the strata within the permit area dip to the north at approximately 7 to 10 degrees. Quaternary alluvial deposits exist in the valleys of the Yampa and Williams Fork Rivers. The Mancos Shale consists of over 5,300 feet of marine shale, with minor interbeds of sandstone and limestone. The Iles Formation overlies the Marcos Shale and underlies the Williams Fork Formation. The strata consist of a massive marine shale between two massive medium- to fine-grained sandstones, the Tow Creek and the Trout Creek sandstones. The Trout Creek sandstone outcrops in the southern part of they permit area along the valley walls of the Yampa River and Williams Fork River. The Trout Creek sandstone is a regional marker. bed at the top of the Iles Formation. The Williams Fork Formation overlies the Trout Creek sandstones of the Iles Formation (See Figure 4). The Williams Fork Formation consists of massive sandstones and shales, and of interbedded and lenticular shales, siltstones, sandstones and coals. The Twentymile Sandstone is a massive [sandstone and is used ae a key marker bed within the region, The Middle Sandstone and White Sandstone are two significant members of the Williams Fork Formation which are laterally extensive in the permit and adjacent areas. Several coal seams are located within the Williams Fork Formation which are minable by underground methods. These include the C, E, F, H and P seams and the Hart seam (See Figure 4). The E seam is being mined in the Eagle No. 6 Mine, the F seam was mined in the Eagle No. 5 Mine, and the P seam was mined at the Eagle No. 9 Mine between 1977 and 1985. Previous mining within the permit area includes the Fields Mine, which operated in the E seam during the 1930'x; the Wise Mine and Wise Hill No. 2 operated in the C seam during the 1940's and :L950's. Previous mining operations in the Hart seam were the Leo White and Baker Mines during the 1930's and the Wise Hill Nos. 3 and 4 in the 1970'x. 6