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<br /> <br /> <br />The youngest strata in the proposed mine area are located in the Lewis <br />Shale Formation. The massive marine shale unit is stratigraphically;situated <br />about 200 feet above the Twentymile Sandstone. Near the base of the <br />Lewis Shale is the Fish Creek Coal Seam. Previous surface mining <br />operations near the northwest corner of the proposed permit area have <br />removed a portion of the Fish Creek Coal Seam. <br />Structurally, the proposed mine is situated along the southeast flank <br />of the Twentymile Park Syncline. This structural feature generally trends <br />northeast-southwest and is doubly plunging forming a structural basin. <br />The strata in the mine area generally dip to the northwest at about 5.7°. <br />No major faults have been identified in the mine area. <br />Generally, the topography in the mine area consists of gently rolling hills. <br />Flatter topography is evident in the valleys of the major streams draining <br />the area (Fish Creek and Foidel Creek). Several prominent cliffs have <br />formed where massive sandstone units, such as the Twentymile Sandstone, <br />outcrop. Like the structure,the overall topography generally dips toward <br />Fish Creek, which represents the approximate center of the Twentymile <br />Park Basin. In the mine area, the structural dip is greater than the <br />topographic dip. <br />The applicant has determined the geochemical characteristics of the roof, <br />floor, and coal strata within the mine area. The results of this analysis <br />are presented in Table 13 of the permit application. No acid-farming, <br />toxic-forming, or alkalinity-producing materials have been identified. <br />/ep <br />cc: Jim Pendleton <br />