_GENERAL DOCUMENTS - C1981017 (262)

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-13- The Iles Formation consists of two sarndston,, members divided by 'I 1 ,0O!) Foot "tongue" of shale. The lower member, the Cozzette, is a o foot layer of very fine grained silty sandstone, which overlies a 40 foot thick layer of silty to sandy shale. The upper sandstone member of the Iles Formation, known as the Rollins, is 120 feet to 140 feet thick. A shale tongue of 5 feet to 30 feet thickness, and identical to the underlying shale, occlirs :within 11:n'2 Rollins member 25 feet to 75 feet above the base. The Rollins sands:,)-�-: varies in grain from very fine to coarse, but medium texture predominates. .lithin the overlying 'Williams Fork Formation, two sandstone members, 'flown as the Middle and Upper sandstone members, separate thick shale formations. above the sandstone members lie coal sia,ns. ,wove the Rollins formation and the "B" bed or Coal Basin seam is a thick layer of mudstones, sandstones and shales of 370 feet to 425 feet in thickness, known as the Lower Bowie Shale Submember. Bowie shale occurs in the Williams Fork Formation. The Middle sandstorn-i submember ovprli :; ;::>> Lower Bowie shale and is similar in many respects to the Rollins sandstone. It ranges in thickness from 30 f-eet to 130 feet and is fine-to-medium grained, quartzitic to feldspathic, poorly to moderately sorted, vrith a clay matrix at the tol). Directly above the 'Middle sandstone is a coaly, black to gray, sandy siitstone which merges into the overlying coal seam, known as "N" Lreek or Middle Bed Seam. The coal seam ran(j!�s from 5 feet to 20 feet thick, and is ruined from the No. 2 mine entry. The overlying sequence is the Upper Bowie shale submember. It consists of mudstcnes, sandstones, and shales and is around 200 feet thick. Tile upper sandstone submember, which overlies the Upper Bowie shale, is up to 100 feet thick. It is similar to the Rollins and -Middle sandstone, except that grain size is somewhat more ooarse. Above the Upper sandstone_, is the Paonia shale member of the Ailliams Fork Formation. It consists of and includes the Placita and Sunshine Coal Intervals. The coal seams fnlned 3 gal 3asin ar,? the "3" i)ed , id c1i? "'nlddle" bed. The two other seams in Coal 3asin are considered uneconomic to mine usino current mining methods. -jrther information on the geology of the permit area can be found in Vol-rne 4, Chapter III-J of the application. The analyses of roof rock and coal (tne floor inacerj .il is c)a1 ) in Section III-D, `lolume 4, indi,.ate thac the ina"tzrials are generally 'ni ;h in iron and have a nigh so.iijm aasorption ratio (S,4R; - A sample of r-),�f