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West Elk Mine <br />• Since 1992, coal qualiryhas been determined from laboratory analyses by Commercial Testing and <br />Engineering Laboratories of Denver, Colorado. Prior to 1992, several other laboratories performed <br />laboratory analyses. <br />Stratigraphy <br />The general geology of this portion of the southeast Piceance Basin consists of gently north- <br />northeastdipping beds of sandstone, shale, and coal of Upper Cretaceous and eazly Tertiary age. <br />The main coal beds aze found in the Upper Cretaceous Mesaverde Group which is overlain by the <br />early Tertiary Ohio Creek Conglomerate and underlain by the Upper Cretaceous Mancos Shale. <br />Locally, the Mesaverde Formation is about 2,500 feet thick. Figure 4 shows a generalized <br />stratigraphic column. Map 9 shows the geology of the permit azea, the coal outcrop line and strike <br />and dip for the F, E, and B-Seams. It has been modified afrer C. R. Dunrud's 1989 geologic map <br />and incorporates more recent geologic mapping data (Intraseazch, Inc. 1993 and 1994). Although <br />Dunrud placed the top of the Upper Coal Member above the F-Seam, MCC uses the top of the F- <br />Seam as the top of the member. <br />stratigraphic cross-sections between drill holes show the subsurface geology through the permit <br />azea. The locations of these cross-sections are shown on Map 10. Figure SA (Cross-Section A-A') <br />crosses the entire lease area from north to south. Figure SB (Cross Section B-B') crosses the initial <br />mining azea (including Federal leases D-044569 and C-0117192) from west to east. Figure SC <br />(Cross-Section C-C') crosses the Jumbo Mountain lease tract (COC-5458) from south to north. <br />• Figure SD (Cross-Section D-D') crosses the Jumbo Mountain lease tract from west to east and is a <br />continuation of the east-west Section B-B' which crosses the initial mining area. Figure SE (Cross- <br />Section E-E') runs down Sylvester Gulch north to south, crossing that portion of the Apache Rocks <br />permit revision azea. Figure SF (Cross-Section F-F') crosses the Apache Rocks permit revision area <br />in a west-east direction. <br />Characteristic lithologic logs have been included for core holes SOM 6, SOM 38, SOM 42, JMB <br />1, SOW-3, RAV-2, RAV-4B, and RAV-7 (Exhibit 12). <br />Mancos Shale <br />The Mancos Shale, the oldest formation exposed in the Paonia area, consists of a sequence of dark <br />gray to buff marine shale approximately2,000 to 3,000 feet thick. <br />Mesaverde Formation <br />The Mesaverde Group conformable overlies the Mancos Shale and is comprised in ascending order <br />of these five stratigraphic units; the basal Rollins Sandstone Member, the Lower Coal Member, the <br />Upper Coal Member, the Barren Member, and the Ohio Creek Member. <br />• <br />2.04-] 6 Revised Jun. 1995 PR06: 1/98 PR08 <br />