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_ __ - _ aN-~ ._. Anticipated mining in the ground water general area include both surface and underground mines (see Figure 3). They are as follows. 1) Trapper Mining Inc. - Trapper Mine, CMLRD Permit No. C-010-81 2) Empire Energy Corporation - Eagle No. 5 and No. 9 Mine - CMLRD File No. C-044-81 3) Energy Fuels Coals, Inc. - Sugarloaf Mine, CMLRD File No. C-060-83 Description of the Existing Environment Regional Geology The geologic formations exposed in the general area are of Late Cretaceous and Tertiary Age. In ascending order, the formations are; the Mancos Shale, the Iles and Williams Fork Formations of the Mesaverde Group, Lewis Shale, Lance formation and the Browns Park Formation. The Mancos Shale is a thick (over 4,000 feet) homogenous light-gray and dark-gray fossiliferous marine shale with interbedded sandstone and limestone beds. This formation is the oldest unit exposed in the area. The sandstones of the Mancos Shale are generally thin-bedded, fine-grained, tan, fossiliferous, and form resistant ledges in the basal and upper parts of the formation. The overall area, where the Mancos Shale is exposed, is characterized by rolling hummocky topography. The Mesaverde Group is approximately 2,100 feet thick and conformably overlies the Mancos Shale. It consists of the Iles Formation and Williams Fork formation. The Iles Formation is the lower formation and is approximately 1,400 feet thick. It consists of interbedded light-brown to white, massive, medium to fine-grained, ledge-forming sandstones, brown to black carbonaceous shale, Sandy shale and coal beds. The coal beds are generally thin and discontinuous, and are not mined in the general area. The sandstone at the base of the Iles Formation is the Tow Creek sandstone. The Trout Creek sandstone caps the top of the Iles Formation. These two sandstones form prominent cliffs and are used in the general area as stratigraphic marker beds. The Trout Creek sandstone averages 61 feet thick in the general area. The Williams Fork Formation conformably overlies the Trout Creek sandstone (Figure 5). This formatton is over 1,700 feet thick in the general area. The Williams Fork Formation has been divided into three units. The lower unit is called the lower coal group. This unit contains sandstones, shales and coal which are characteristic of continental deposit formed in transitional to lower delta plain environments. Economically important coal seams found in the lower coal group are the "C", "E" and "F" seams. The "F" seam is being mined at the Eagle No. 5 Mine. The Trapper Mine is mining no coal seams in this group, and the proposed Sugarloaf Mine has plans to mine all strippable seams in this group.