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May 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 prepared subsidence control, monitoring, and <br />mitigation plans for surface structures over projected room - and - pillar panels to be mined in <br />either the Allen or the Apache seam at the New Elk Mine (New Elk). <br />New Elk plans to mine the Allen or Apache seams in different areas of the mine using <br />development -only room -and- pillar mining with no anticipated subsidence. Nine -entry <br />production panels are currently projected, with an entry width of 20 feet (ft). The pillar and <br />panel dimensions vary according to cover depth. The panel lengths are variable, and inter -panel <br />barrier widths are equal to the widths of panel pillars. No pillar extraction is planned. The <br />planned extraction thickness in the Allen seam varies from 5 to 6.5 ft; the planned extraction <br />thickness in the Apache seam varies from 4 to 5 ft. Multi -seam mining involving the Allen and <br />Apache seams is not anticipated at this time. <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 permit Map 20. Table 1 <br />identifies the approximate depth to the Allen seam (the deeper of the two seams) corresponding <br />to the sites shown in Map 20, Sheets 1 -3, dated April 20, 2011. Other structures near the mine <br />site such as the mine plant buildings, the San Isidro -St. Francis Church and the Vigil School <br />located on both the north and south side of SH 12 are outside the limit of influence of mining. <br />2.0 BACKGROUND INFORMATION <br />The renewable resource lands existing in the form of the Purgatoire River and associated <br />alluvial valley floor are unlikely to be impacted by this mining plan. The location of this <br />renewable resource is shown on Map 20. The description of the renewable resource lands has <br />been completed and is shown in Exhibit 8. The current mining plan under the Purgatoire River <br />and associated alluvial valley floor are development -only workings and do not have any retreat <br />panels. All maps and exhibits referenced in this report may be found in the New Elk permit <br />document C1981012 (current permit). <br />No subsidence features were observed in the Refuse Disposal Area (RDA). According to <br />available mine maps and discussions with long -time mine personnel, this area was undermined <br />as part of the Allen Mine in the early 1960s using room - and - pillar mining methods, and recovery <br />was less than 50 %. The Refuse Disposal Area will be located over the far northeast part of the <br />mined area which has been only partially undermined. The Refuse Disposal Area will be located <br />from 320 to 900 feet over the old workings. <br />Agapito Associates, Inc. <br />