2006-06-02_PERMIT FILE - C1980007A (3)

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West Elk Mane Minnesota Creek. Some burning of the B Seam has occurred along outcrops on Jumbo Mountain and in the Minnesota Creek drainage, predominantly on south and west-facing slopes. B Seam Litholo~ The B Seam typically comprises three coal benches separated by persistent rock partings. The coal benches have been designated in descending sequence as B1, B2, and B3 (Figure 6). All three benches aze present in the permit area with varying thickness. In other azeas of MCC's lease holdings the minable portion of the B Seam occurs at the top of the seam where the Bl and B2 benches aze closely associated and attain sufficient combined thickness. In these areas, the upper coal benches are thinly separated by a parting informally called the "Mazker Parting" and formally designated as the Ml Parting. The M1 Parting in the permit area varies from 0.2' in the north to 29.6' in the south at hole MG-15. Its irregular occurrence may preclude or limit the potential for longwall mining. The M2 Parting is also present in the B Seam within the South of Divide permit area. The M2 Parting develops in the upper section of the B2 coal bench typically 1.5' to 2.0' below the Ml Parting, decreasing the mineable bench of coal to the lower B2 bench. The M2 Parting has been encountered previously in the B Seam reserve in the Jumbo Mountain and Box Canyon leases. Parting composition varies from bone and carbonaceous mudstone on the fringes to fine-grained siltstones and sandstones as the parting thickens. In the Box Canyon reserve, the M2 Parting at 0.5' • or greater in thickness defines the mineable boundary for longwall mining using current technology. Beneath the B2 coal bench, a thick rock parting separates the mineable portion of the B Seam from the lowermost, impure B3 coal bench (Figure 6). Because of its posifion neaz the base of the mining interval, this parting is informally called the "Lower Parting." The underlying B3 coat bench contains numerous bone and shale partings, and as a result, is not of salable quality. This coal bench grades downwazd and laterally into a carbonaceous shale. The contrast in coal quality between the upper, mineable portion of the B Seam and the impure, lower bench is shown in Table 2, along with the average as-shipped quality of the B Seam from the Box Canyon reserve and the E Seam from the South of Divide reserve. Table 2 Average Coal Quality U er Lower Product Quali Parameter B Seam B Seam B Seam E Seam F Seam In situ In situ Actual Projected Actual Moisture (%) 7.7 7.8 8.5 11.1 10.0 Ash (%) 7.1 16.8 9.5 6.5 9.7 BTU (%) 11,900 10,800 11,900 11,700 11,300 Sulfur (%) 0.6 0.4 0.7 0.4 0.5 2.04-23 RevrsedNou~m8er1004 PRIG