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• claystones and clay-shales, accumulated in poorly drained swamps in overbank <br />or flood bank areas. Some coal deposits may have been developed in <br />abandoned channels. The thickest coal beds were formed in more stable parts <br />of the swamp. <br />The area in Sec. 25 and Sec. 26, T3N, R64W has coal that is representative of <br />deposition in broad swamp areas. Occasional clay and silty clay partings within <br />the lower 2 ft. of coal bed may have resulted from sediment laden waters <br />breaking through levees (crevasse splays) and depositing fine to medium <br />grained sand in the overbank/swamp area. The occurrence of partings may <br />indicate proximity of the coal "crop" or boundary. Coal thickness in the <br />proposed B-Pit area averages 7.0 ft.. <br />In the Laramie Formation, seven coal seams have been identified to exist in the <br />Denver Basin. The coal seam being mined is the No. 7 seam, which is <br />stratigraphically the highest or youngest seam in the Laramie coal group. The <br />No. 7 seam is the only coal seam that appears to be present in the lower <br />Laramie at the mine site. <br />The geologic formations of major interest that will be affected during proposed <br />mining activities are the unconsolidated eolian sands and the underlying <br />Laramie Formation clays, clay-shales, claystones, sands and the uppermost coal <br />• seam. <br />The Laramie sandstone and Fox Hills sand stone (Laramie-Fox Hills aquifer) <br />lie approximately 210 foot below the expected maximum depth of mining and <br />should not be affected by mining activities <br />• <br />41 <br />