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2.04.6(3) Exhibit 8, Drill Hole Logs, and is graphically shown on the Geologic Cross Section (Map 7). Topographic locations of the geologic cross sections, along with site specific geology including coal outcrops are found on the Geology/Hydrology Map (Map 6). Site-Saecific Geology The C Coal Seam roof consists of 5 to 12 feet of shale, overlain by massive sandstone. The B Coal Seam roof consists of interbedded shale and sandstone. In general, the C Seam roof material is reasonably competent, but is subject to deterioration when exposed to the cycles of moisture attendant with mine ventilation. For this reason, 6 to 12 inches of top coal are sometimes left to prevent shale exposure. The B Seam roof material is generally more competent than the C Seam roof and typically no top coal is left. The floor of the C Coal Seam is characterized by 5 to 12 feet of interbedded sandstones and shales. The floor is sufficiently competent for the operation of mining equipment. Therefore, no • bottom coal is left. The floor of the B Coal Seam is coal since the seam is over 20 feet thick. The overburden above the C and B Coal Seams vary from a few hundred feet near the north edge of the permit boundary to over 1,500 feet in areas near the south central portion of the permit area. Coal or rider seams above the C and B Coal Seams include the identified D, E, and F Coal Seams, all in the Upper Coal Member. The D Coal Seam is variable in thickness, but averages only about 3 feet in thickness. The E Coal Seam averages about 7 feet in thickness. The F Coal Seam averages about 6 feet in thickness. Above the F Coal Seam, there are about 5 minor rider coal seams. The A Coal seam, which is relatively thin, is located below the B Seam. Coal Ouality The coal seams to be mined from the Bear No. 3 Portals will be the C and B Coal Seams; the quality of the seams appear to be quite uniform • 2.04-20 Rev. 09-26-94