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- 6 - <br />' ance: the upper coal member, the top of which was defined by <br />Woodward-Clyde Consultants as coinciding with the top of the <br />F seam, and the barren member which overlies it. The upper <br />coal member is approximately 220 feet thick, and the barren <br />member is about 1,500 feet thick. <br />The upper coal member is composed of shales, siltstones, <br />sandstones, and three persistent economic coal seams, known <br />as the D, E, and F seams. The barren member includes sand- <br />, stones, siltstones, and shales with a few scattered lenticu- <br />lar coal seams. A schematic geologic section of the area is <br />' shown on Plate 2. <br />I The Mesaverde Formation at the site area dips general- <br />ly three to five degrees to the north - northeast. The <br />structure of the coal seams is very similar, showing only <br />' minor variations. No major faults are known to exist within <br />the vicinity of the project area. <br />No detailed measurement of joints has been carried out. <br />' The Atlantic Richfield Company, Synthetic Crude and Mineral <br />Division, compiled data on fractures and joints on the proper- <br />' _ ty. They came to the conclusion that two important joint <br />sets exist on the site. They trend generally north-south and <br />east-west, and they dip near vertically. This evaluation <br />agrees closely with other available data on jointing within <br />' the Mesaverde Formation. <br />There are few data available on the character and thick- <br />, ness of the soil cover. It is known from the previous in- <br />vestigations that most soils on the site are of colluvial <br />' origin. They have been derived from the underlying bedrock <br />and have a character of clayey, sandy, or silty soils. Frag- <br />1 <br />ceo+~raro ea+w~mw, n+c. <br />