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Iles formation conformably overlies the Mancos shale and makes up the • lower part of the Mesaverde group. The lower two-thirds of the formation con- sists of approximately 1,000 feet of massive sandstones interbedded with sandy shales, shales, and coal beds. The upper one-third of the formation consists of approximately 500 feet of shales capped by a 100-foot-thick, white, massive sandstone called the Trout Creek sandstone member. The Meadows No. 1 mine removed Pinnacle seam coal from this formation. Map 4A provides information on drill hole locations, geologic setting prior to reclamation, and the dip and strike of the coal seams. Much of the coal has been removed by strip mining operations. The coal seams strike from slightly east of north (approximately 5 degrees) to slightly west of south. The Williams Fork formation makes up the upper Mesaverde group and confor- mably overlies the Iles formation. The formation is approximately 1,100 feet • thick and is made up of a sequence of sandstones, shales, and coal beds. The formation is divided into a lower member, consisting chiefly of thin sandstones, shales, and several coal beds; a middle member consisting of a white, massive sandstone called the Twentymile sandstone; and an upper member consisting of sandstone, shale, and coal. The Lewis shale conformably overlies the Williams Fork formation and con- sists of dark grey to blue homogeneous marine shale. Coal Previously published reports indicate between 20 and 40 measurable coal seams to be within the Williams Fork and Iles formations. These reports, substantiated by field investigation and mining, have illustrated that there are three uniformly correlatable seams in the Williams Fork and two seams in the Iles in the area of the Sun Coal property. These seams in descending order are - 66 - (Rev. 5/86)