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October 11, 2011 Page 1 <br />NEW ELK COAL COMPANY <br />SUBSIDENCE CONTROL, MONITORING, AND MITIGATION PLAN <br />1.0 INTRODUCTION <br />Agapito Associates, Inc. (AAI) has performed an analysis to predict mining- induced <br />subsidence over projected multi -seam room - and - pillar panel workings to be mined in the Blue, <br />Apache, and Allen Seams at the New Elk Mine (New Elk) for the TR58 mine plan. AAI has also <br />prepared control, monitoring, and mitigation plans for surface structures that may be affected by <br />mining- induced subsidence above the aforementioned multi -seam workings. <br />New Elk plans to mine the Blue, Apache, and Allen Seams in different areas of the mine <br />using retreat room - and - pillar mining with planned subsidence. At selected locations, pillar <br />extraction panels from the Blue, and one of either the Apache or the Allen Seams, are projected <br />to overlap. The TR58 mine plan has seven -entry production panel projections, with entry widths <br />of 20 feet (ft). The pillar and panel dimensions vary according to cover depth. Ninety-ft -wide <br />(center -to- center) pillars are projected to be the preferred size. The panel lengths are variable, <br />and inter -panel barrier widths are equal to the widths of panel pillars. Inter -panel barriers and <br />panel pillars will be mined during retreat. Ideally, the plan would result in full extraction of the <br />production and barrier pillars. The planned extraction thickness for multi -seam workings with <br />vertical overlap, within the permit boundary, is 5 ft in all the seams given that the total thickness <br />in these workings is less than 5 ft. The planned sequence of multi -seam mining is top -to- bottom; <br />the Blue Seam first, followed by either the Apache or the Allen Seam. <br />This report presents subsidence control, monitoring, and mitigation plans for the gas <br />wells, pipelines, and ancillary structures. Similar plans for structures such as houses and roads <br />are also discussed. The structures to be protected are shown on the attached drawing. Table 1 <br />identifies the approximate depth to the Allen Seam (the deepest of the multi -seam targets) <br />corresponding to the sites shown in Map 20, Sheets 1 -3. Other structures, such as the mine plant <br />buildings, the San Isidro -St. Francis Church and the Vigil School, are outside the mining limit of <br />influence. <br />It should be noted that in lieu of protecting structures, it may be possible to negotiate <br />agreements with structure owners to take certain structures out of service, fully subside them, <br />and repair or replace the structures after subsidence is no longer active. The feasibility of such <br />an approach would depend on the value of the structure as compared to that of the resource, <br />would require the cooperation of structure owners, and would have to be evaluated on a case -by- <br />case basis. <br />Agapito Associates, Inc. <br />