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The split in the Wolf Creek coal seam was caused by an influx of distal splay deposits from <br />nearby streams which covered the initial peat deposits (lower Wolf Creekl. As the swamp <br />reestablished itself, these distal splay deposits were later covered with more peat (upper Wolf <br />Creek, Gaffke, 19791. Above the upper Wolf Creek coal bed lies about 100 to 150 feet of <br />sandstones, shales, siltstones, and thin coals. Above this interval lies the Sage Creek coal bed <br />which outcrops just to the northwest of the Wolf Creek outcrop and east of the Wadge outcrop <br />in the southern part of the permit area. The Sage Creek coal ranges in thickness from about <br />two feet to five feet. Overlying the Sage Creek coal is about 50 to 65 feet of principally <br />sandstone interbedded with shales and siltstones. This interval of strata, although dominated <br />by sandstone, exhibits some facies changes, extensive lensing and interbedding among the <br />lithological types present. Exhibit 6-5A and 6-56 are overburden isopach maps representing <br />strata to be removed during mining of the selected areas of the Sage Creek and Wolf Creek <br />seams. The Wadge coal seam is immediately above this sequence of strata. <br />The Wadge coal seam, the principal seam to 6e mined, has the most continuous outcrop of any <br />coal seam within the permit area. The outcrop strikes roughly north-south along the eastern <br />half of the permit boundary. The Wadge seam also outcrops in an eroded area located in the <br />central portion of the permit area in Section 22. The Wadge seam, like the Wolf Creek seam, <br />is split into an upper and a lower seam over most of the northern part and a portion of the <br />southern part of the permit area. The depositional processes responsible for this splitting were <br />much the same as those affecting the Wolf Creek seam. The lower Wadge is underlain by <br />mostly shales, silstones, and sandstones, and is about two to three feet thick. A two to five- <br />foot interval of shales and sandstones separates the upper Wadge from the lower Wadge. The <br />upper Wadge is usually about ten feet thick. In areas where the Wadge seam is not split, it is <br />typically 11 to 13 feet thick. West of its outcrop, the Wadge is overlain by 50 to 60 feet of <br />principally sandstone interbedded with shales and siltstones. This interval of strata is very <br />similar to that underlying the Wadge coal seam. However, the shales and siltstones appear to <br />comprise more of the strata above than below the Wadge. The Lennox coal seam is <br />immediately above this sequence of strata. It is usually two to five feet thick, but has been <br />eroded away in some areas. Exhibits 6-4 and 6-5 are overburden isopach maps representing <br />strata to be removed during mining of the Wadge coal seam. <br />The material above the Lennox coal consists of relatively thick sequences of shales, sandy shales, and <br />siltstones which outcrop throughout most of the northwestern and southern portions of the permit <br />area. Sandstones become more prevalent toward the top of this section (Figure 6-21~ The total <br />thickness of these overlying beds is approximately 500 feet. The sandstones are mostly <br />fine to very fine grained, light gray, and well sorted; the shales are commonly silty with some <br />carbonaceous material at varying depths. At the top of this sequence lies the Twentymile <br />sandstone member of the Williams Fork Formation. <br />The Twentymile sandstone outcrops within the western portion of the Seneca II-W lease area, <br />and like the Trout Creek sandstone, is a marine sandstone. The thickness of the Twentymile <br />PR03 7 Revised 01/02 <br />