2022-02-22_PERMIT FILE - C1980007 (5)

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West Elk Mine 2.04-13 Rev. 11/04- PR10; 07/18- PR15; 01/22- MR459 Denver, Colorado conducted the laboratory analyses. Prior to 1992, several other laboratories performed laboratory analyses. Stratigraphy The general geology of this portion of the southeast Piceance Basin consists of gently north- northeast dipping beds of sandstone, shale, and coal of Upper Cretaceous and early Tertiary age. The main coal beds are found in the Upper Cretaceous Mesaverde Group which is overlain by the early Tertiary Ohio Creek Conglomerate and underlain by the Upper Cretaceous Mancos Shale. Locally, the Mesaverde Formation is about 2,500 feet thick. Figure 4, shows a generalized stratigraphic column. Map 9 shows the geology of the permit area, the coal outcrop line and strike and dip for the F, E, and B Seams. It has been modified after C. R. Dunrud's 1989 geologic map and incorporates more recent geologic mapping data (Intrasearch, Inc. 1993 and 1994). Although Dunrud placed the top of the Upper Coal Member above the F-Seam, MCC uses the top of the F Seam as the top of the member. Stratigraphic cross-sections between drill holes show the subsurface geology through the permit area. The locations of these cross-sections are shown on Map 10. Figure 5A (Cross-Section A-A') crosses the lease area from north to south. Figure 5B (Cross Section B-B') crosses from the Fee land in the north through the Fee land in the south (including Federal leases C-56447 and C-1362. Figure 5C (Cross-Section C-C') crosses lease C-56447 from the north to C-1362 to the south in the eastern area of the leases. Figure 5D (Cross-Section D-D') crosses west to east over C-0117192 through C-044569 to C-56447. Figure 5E (Cross-Section E-E') runs west to east on the northern edge of the South of Divide permit revision area. Figure 5F (Cross-Section F-F') crosses the center of South of Divide permit revision area from west to east. Characteristic lithologic logs have been included for core holes SOM 6, SOM 38, SOM 42, JMB 11, SOW-3, RAV-2, RAV-4B, and RAV-7 (Exhibit 12). Mancos Shale The Mancos Shale, the oldest formation exposed in the Paonia area, consists of a sequence of dark gray to buff marine shale approximately 2,000 to 3,000 feet thick. Mesaverde Formation The Mesaverde Group conformable overlies the Mancos Shale and is comprised in ascending order of these five stratigraphic units; the basal Rollins Sandstone Member, the Lower Coal Member, the Upper Coal Member, the Barren Member, and the Ohio Creek Member.