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West E[k Mine Representative samples-of the B-Seam coal, overburden, roof, and floor strata have been collected and analyzed from core holes drilled within the mine petzrtit azea, and elsewhere azound the lease holdings. The location of these holes are shown on Map 8 and the analytic results are presented in Exhibit 13. Stratigraphic cross-sections and geochemical analyses indicate that these results are representative of the existing conditions throughout the West Elk coal lease azea. Table 3 Recoverable Reserves (MM Tons) Reserves B-Seam* E-Seam** Total Federal Leases 89 62 151 Fee 3 0 3 Total 92 62 154 Assumptions: All reserve estimates based upon MCC's 1998 Long Range Mine Plan dated June 1997. ` Coal weight@ 861bs.lft.', 8 ft. minimum miningheight, 12 ft. maximum miningheight. "' Coal weight@ 82 lbs./ft.', 8 ft. minimum mining height, 1 I ft. maximum mining height. .i B-Seam Roof and Floor Core examination and actual observed conditions suggest that the B-Seam has the most competent roof rocks of the three mined or minable seams. Immediately overlying the B-Seam is from 1 to 2 feet of a dark gray mudstone. This lithology is generally competent, but may locally be weakened where slickensides, fossils, or joints disrupt bedding continuity and rock strength. Above this fine- grained "cap rock", a widespread sandy unit occurs which forms the main roof of the B-Seam. This sandstone typically provides good anchorage for roof bolts and forms a strong beam above the mined entries. Locally, this sandy unit may be weakened by jointing or thin, fine-grained laminations, which commonly occur near the unit's base. B-Seam roof conditionshave historically been excellent. From 1 to 2 feet of top coal is commonly left urtmined in the roof to improve roof conditions by eliminating air slaking, which can weaken the immediate roof shale over time. In leaving top coal, sulfur in the coal product is also reduced by avoiding higher concentrations of sulfur that occur neaz the top of the seam. The base of the B-Seam is predominately comprised of siltstone and shale. Because all of the lower coal bench (B3) is left urtmined and in place for quality reasons, floor conditions of the normal mining interval are generally excellent. On occasion, floor conditions degrade when mining inadvertently encounters the lower claystone parting (Figure 6). 2.Q4-29 Revised Jun. 1995PR06; Revised Jan. /998 PROS