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EXHIBIT 60E <br />SUBSIDENCE EVALUATION <br />FOR THE SOUTH OF DIVIDE AND DRY FORK MINING AREAS <br />1.0 INTRODUCTION <br />This exhibit describes subsidence processes that have been observed from studies above longwall <br />mining panels in Mountain Coal Company, LLC's (MCC) West Elk Mine and from other similar <br />operations and studies. The subsidence information obtained from the current West Elk Mine <br />area has been used to project subsidence processes, amounts, and effects to the South of Divide <br />and Dry Fork mining areas within MCC's permit and affected area boundary. This document is <br />intended to comply with the Colorado Division of Reclamation, Mining and Safety (DBMS) <br />Regulations for Coal Mining, as revised September 14, 2005, under Section 2.05.6, Mitigation of <br />the Impacts of Mining Operations. <br />This report was updated by Tetra Tech September 2007 and was added to the approved permit <br />document as Exhibit 60E to include the Dry Fork lease mining area with the mining area of the <br />South of Divide coal leases within the permit area. Since these areas are being mined together, it <br />is logical to consider them together in one report. Most of the report is "as contained" in the <br />Exhibit 60B prepared by C. Richard Dunrud of Wright Waters Engineers, Inc. (WWE) in March <br />2006 for the South of Divide mining area. Planned and maximum projected mining into the Dry <br />Fork mining area will occur in E-seam longwall panels E2 through. E6 to the east permit area <br />boundary and under the upper areas of Dry Fork, a tributary to Minnesota Creek, and the upper <br />areas of Deep Creek. Panels E1, E7, E8, and E9 remain within the boundaries of the South of <br />Divide mining area previously evaluated. <br />WWE further updated Exhibit 60E to reflect the maximum projected areal extent of potential <br />longwall. mining (also referred to as the Projected Potential Mining Area shown on MCC's <br />permit Map 51 and shown as dashed lines on the east end of longwall panels E2 through E6 in <br />Figure 1) within the potential mineable coal reserves of the Dry Fork mining area. MCC's <br />projected E-seam mining, as depicted with solid lines in Figure 1, has not changed and continues <br />to reflect the best available information (including exploration and actual E-seam mining data) <br />regarding the mineable E-seam coal. However, during ongoing panel development, additional <br />mineable coal has been and may be found to exist beyond the projected E-seam mining shown on <br />permit Map 51. If mineable coal is found beyond the projected mining and is within the <br />Projected Potential Mining Area, MCC may continue mining within this area. Throughout <br />Exhibit 60E, the maximum projected areal extent of longwall panels (the dashed lines on Figure <br />1) are also included as part of the longwall panels for which subsidence is being evaluated. <br />The geologic and mining conditions in the Dry Fork area are nearly identical to the South of <br />Divide area (Agapito, 2005). Therefore, no change was needed in the subsidence model prepared <br />831-032.810 Wright Water Engineers, Inc.