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EXHIBIT 60E <br /> SUBSIDENCE EVALUATION <br /> FOR THE SOUTHERN PANELS, APACHE ROCKS WEST, <br /> & SUNSET TRAIL MINING AREAS <br /> 1.0 INTRODUCTION <br /> This exhibit describes longwall panel subsidence processes that have been observed from studies <br /> above longwall panels mined in Mountain Coal Company,LLC's(MCC)West Elk Mine and from <br /> other similar operations and studies. The subsidence information obtained from longwall mining <br /> to date in the West Elk Mine has been used to project subsidence processes, amounts, and effects <br /> to the Southern Panels, Apache Rocks West, and Sunset Trail mining areas within MCC's permit <br /> and affected area boundaries. This document is intended to comply with the Colorado Division of <br /> Reclamation, Mining and Safety(DRMS) Regulations for Coal Mining, as revised September 14, <br /> 2005,under Section 2.05.6, Mitigation of 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 longwall mining area <br /> of the South of Divide coal leases within the permit area. Since these areas are being mined <br /> together, it is logical to consider them together in one report. Most of the report is "as contained" <br /> in the Exhibit 60B prepared by C. Richard Dunrud of Wright Waters Engineers, Inc. (WWE) in <br /> March 2006 for the South of Divide mining area. Maximum projected mining was planned into <br /> the Dry Fork mining area in E-seam longwall panels E2 to E6 to the east permit area boundary and <br /> under the upper areas of Dry Fork, a tributary to Minnesota Creek, and the upper areas of Deep <br /> Creek. Panels E1, E7, E8, and E9 remain within the boundaries of the South of Divide mining area <br /> previously evaluated. <br /> WWE further updated Exhibit 60E to reflect the maximum projected areal extent of potential <br /> longwall mining within the potentially mineable coal reserves of the Dry Fork mining area. MCC's <br /> projected E-seam mining has not changed and continues to reflect the best available information <br /> (including exploration and actual E-seam mining data) regarding the mineable E-seam coal. <br /> However,during ongoing longwall panel development,additional mineable coal has been and may <br /> be found to exist beyond the projected E-seam longwall panel shown on permit Map 51. If <br /> mineable coal is found beyond the projected longwall panel and is within the Maximum Projected <br /> Areal Extent area, MCC may continue mining within this area. <br /> The 2015 update addressed a revised longwall panel layout in the two-seam mining area known as <br /> the Apache Rocks West panels that was addressed in the original Exhibit 60 (May 1995). In <br /> addition, the update evaluated the subsidence due to two-seam mining in the Southern Panels <br /> mining area as shown in Figure 1. The 2018 update evaluated the subsidence associated with <br /> longwall mining of the E-seam in the Sunset Trail mining area. WWE analyzed the proposed <br /> layout for longwall panels SS 1 through SS4 as shown in Figure 1. The 2020 update was performed <br /> 831-032.912 Wright Water Engineers, Inc. <br /> December 2020 <br />