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The split in the Wolf Creek coal seam was caused by an influx of distal splay deposits from • nearby streams which covered the initial peat deposits (lower Wolf Creekl~ As the swamp reestablished itself, these distal splay deposits were later covered with more peat (upper Wolf Creek, Gaffke, 19791. Above the upper Wolf Creek coal bed lies about 100 to 150 feet of sandstones, shales, siltstones, and thin coals. Above this interval lies the Sage Creek coal bed which outcrops just to the northwest of the Wolf Creek outcrop and east of the Wadge outcrop in the southern part of the permit area. The Sage Creek coal ranges in thickness from about two feet to five feet. Overlying the Sage Creek coal is about 50 to 65 feet of principally sandstone interbedded with shales and siltstones. This interval of strata, although dominated by sandstone, exhibits some facies changes, extensive lensing and interbedding among the lithological types present. The Wadge coal seam is immediately above this sequence of strata. The Wadge coal seam, the principal seam to be mined, has the most continuous outcrop of any coal seam within the permit area. The outcrop strikes roughly north-south along the eastern half of the permit boundary. The Wadge seam also outcrops in an eroded area located in the central portion of the permit area in Section 22. The Wadge seam, like the Wolf Creek seam, is split into an upper and a lower seam over most of the northern part and a portion of the southern part of the permit area. The depositional processes responsible for this splitting were much the same as those affecting the Wolf Creek seam. The lower Wadge is underlain by mostly shales, silstones, and sandstones, and is about two to three feet thick. A two to five- • foot interval of shales and sandstones separates the upper Wadge from the lower Wadge. The upper Wadge is usually about ten feet thick. In areas where the Wadge seam is not split, it is typically 11 to 13 feet thick. West of its outcrop, the Wadge is overlain by 50 to 60 feet of principally sandstone interbedded with shales end siltstones. This interval of strata is very similar to that underlying the Wadge coal seam. However, the shales and siltstones appear to comprise more of the strata above than below the Wadge. The Lennox coal seam is immediately above this sequence of strata. It is usually two to five feet thick, but has been eroded away in some areas. Exhibits 6-4 and 6-5 are overburden isopach maps representing strata to be removed during mining of the Wadge coal seam. The material above the Lennox coal consists of relatively thick sequences of shales, sandy shales, and siltstones which outcrop throughout most of the northwestern and southern portions of the permit area. Sandstones become more prevalent toward the top of • 7 Revised 9/98