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Mountain Coal Company, L.L.C. Exhibit 51 West Elk Mine ~ Lower Refuse Pile • 4.0 TOPSOIL AND SUBSOIL SALVAGE AND STORAGE ~.1 Topsoil and Subsoil Salvage Topsoil depths were observed in test borings and test pits in the area of the proposed disposal site and found to ranee from 12 inches to 5 feet. A depth of 18 inches, however, would be considered typical. The test borings also indicate subsoil present in sufficient quantities to cover the refuse pile with an additional 36 inches of cover, should the variance have been declined. See Section 23 for a discussion of the materials balance. 4.2 Topsoil Storage Topsoil storage for Phases I through III were located south of the pile construction in the area indicated on Figures LWP-002 through LWP-004. This area contained a long ridge of triangular cross-section with 2H: I V sideslopes, varying in height from 16 to 37 feet. The ends were conical, also with 2H:1 V slopes. The estimated maximum volume of topsoil that was stored in this area was approximately 28,00 cubic yards. Atypical cross-section is provided in Figure LWP-007 in Appendix D. For Phase IV, topsoil was stockpiled on the SO-foot bench constructed in Phase Ill. The topsoil stockpile was a parallelogram shaped cross-section having 2H:IV slopes and a maximum height of 40 fee[. A 10-foot buffer zone was maintained between the toe of the topsoil pile and the edge of the bench. The cross-section of this area may be found in cross section A-A, Figure LWP-Ol 1, in Appendix K. It was estimated that this area had a maximum storage capacity of approximately49,000 cubic yards. ., - a Topsoil storage at the end of Phase IV was on [he east and north benches of the LRP, as shown in Appendix B, Figure 2.OB. To begin construction of Phase V, it was necessary to relocate the stockpiles. Topsoil storage during Phase V construction was along [he western edge of the existing refuse pile [op, as shown in Appendix B, Figure 2.OE. The stockpile had sideslopes no steeper than 2H:1 V. A 3 to 6- inch lift of subsoil was laid down to keep the tupsoil segregated from the underlying coal refuse. Surface water runoff was controlled with the sediment control ditches already in place for the LRP. The topsoil pile was later moved to the North Soil Storage Area (NSSA) An average 9 to 12-inch cover of topsoil will be placed on top of the 9 to 12-inch cover of subsoil. Roughly 13.270-cy of topsoil will be required to reclaim the phase V construction. 4.3 Subsoil Storage A subsoil stockpile lies immediately south of the maximum southern extent of [he pile and west of Sylvester Gulch, and is identified as the Sylvester Gulch Live Subsoil Stockpile ay I. The height of the pile varies with the volume in storage and will vary with each phase: The maximum amount of material that can be stored is estimated to be approximately X8,000 cubic yards. Across-section of [he pile has been prepared showing [he pile at its anticipated maximum height (see figure LWP-008 in Appendix D). Visual monitoring of the subsoil pile will be performed on a monthly basis (and reported in quarterly inspections) to assure that any possible slumping will be repaired as soon as possible. Subsoil was temporarily stored on the northern portion of [he west-facine slope of the lower refuse pile. This subsoil was distributed over the lower portion of the west slope of the LRP for reclamation after a refuse buttress was completed (seeFieure2.0A). 9