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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 subsidence processes that have been observed from studies above longwall <br />panels mined in Mountain Coal Company, LLC's (MCC) West Elk Mine and from other similar <br />operations and studies. The subsidence information obtained from mining to date in the West Elk <br />Mine has been used to project subsidence processes, amounts, and effects to the Southern Panels, <br />Apache Rocks West, and Sunset Trail mining areas within MCC's permit and affected area <br />boundaries. This document is intended to comply with the Colorado Division of Reclamation, <br />Mining and Safety (DRMS) Regulations for Coal Mining, as revised September 14, 2005, under <br />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 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 Exhibit <br />60B prepared by C. Richard Dunrud of Wright Waters Engineers, Inc. (WWE) in March 2006 for <br />the South of Divide mining area. Maximum projected mining was planned into the Dry Fork <br />mining area in E -seam longwall panels E2 to E6 to the east permit area boundary and under the <br />upper areas of Dry Fork, a tributary to Minnesota Creek, and the upper areas of Deep Creek. Panels <br />E1, E7, E8, and E9 remain within the boundaries of the South of Divide mining area previously <br />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 panel development, additional mineable coal has been and may be found <br />to exist beyond the projected E -seam mining shown on permit Map 51. If mineable coal is found <br />beyond the projected mining and is within the Maximum Projected Areal Extent area, MCC may <br />continue mining within this area. Throughout Exhibit 60E, the maximum projected areal extent <br />of longwall panels are also included as part of the longwall panels for which subsidence is being <br />evaluated. <br />The 2015 update addressed a revised panel layout in the two -seam mining area known as the <br />Apache Rocks West panels that was addressed in the original Exhibit 60 (May 1995). In addition, <br />the update evaluated the subsidence due to two -seam mining in the Southern Panels mining area <br />as shown in Figure 1. The 2018 update evaluates the subsidence associated with mining of the E- <br />831-032.816 Wright Water Engineers, Inc. <br />October 2018 <br />