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Possible development of surface cracking where the overburden is less than 500 feet thick and the soil cover <br />is thin. <br />The predicted maximum possible worst case subsidence for the various structures and renewable resource lands is <br />summarized on Table 79, Maximum Predicted Worst Case Subsidence on Structures and Renewable Resource Lands. <br />A summary of the anticipated degree of subsidence impacts on structures and renewable resource lands is presented <br />on Table 80, Anticipated Degree of Subsidence Impact on Structures and Renewable Resource Lands Based on <br />Maximum Predicted Worst Case Subsidence. <br />The following is a description of the worst possible consequences of subsidence on the structures and renewable <br />resource lands identified on Table 78, Inventory of Structures and Renewable Resource Lands, which may occur as a <br />result of mining in the planned permit area. <br />Structures <br />Mine Facilities (Not Undermined). The mine facilities located at or adjacent to the portal areas for the No. 5, No. 5A, <br />and No. 9 Mines will not be undermined. Since these structures will not be undermined and are outside the area of <br />influence of surface subsidence resulting from the planned underground mining, they will not be impacted by <br />subsidence. <br />Mine Facilities (Presently Undermined). The mine facilities within the Permit Area that are presently undermined, or <br />that will be undermined, are located over development entries (mains and sub -mains) which are designed to remain <br />stable for the life of the mine. These areas have been protected against subsidence damage by assuring that sufficient <br />coal has been left in-place as pillars to prevent or minimize subsidence in these areas. In addition, areas of Trapper <br />Mining, Inc.'s surface mining operation which have been previously mined and reclaimed have been partially <br />undermined. The Trapper Mining reclaimed areas that have been undermined, were undermined without any material <br />damage. Given these considerations, no subsidence impacts have occurred or are anticipated for these structures and <br />areas. <br />Mine Facilities (To Be Undermined). The mine facilities under which proposed mining will be conducted include <br />MCM's underground F -Seam and P -Seam workings. Proposed mining will undermine underground mine workings in <br />both the No. 5 and No. 9 Mines, however, none of the No. 9 Mine workings have been undermined to date, so <br />potential impacts would be limited to any future mining. The MCM surface facilities that would be undermined <br />include Sedimentation Ponds SH -P1, SH -P2 and the associated Old Shop and storage area (reclaimed in 2008), a rock <br />dust tank, the contractor staging area, the Storage and Wood Shop, and the Okie Plaza well. Based on MCM's site- <br />specific experience, mining -related surface subsidence is not expected to significantly impact sedimentation ponds or <br />general facilities areas, however, there may be some limited reduction in surface elevations over the mined -out areas. <br />The MCM surface facilities that would be undermined by potential future operations in the E -Seam include: 1) Old <br />Shop and storage area; 2) Ponds SH -P1 and SH -P2 and associated ditches SH -D2 and SH -D3; 3) Rock -dust tank; 4) <br />contractor staging area; 5) Storage and Wood Shop; and 6) Okie Plaza Well. The Old Shop and storage area, rock <br />dust tank, and Storage and Wood Shop, and associated disturbance areas have been reclaimed. Ponds SH -P1 and SH - <br />P2 and ditches SH -D2 and SH -D3 will be monitored closely during subsidence. Pre- and post -subsidence surveys and <br />monthly inspections between surveys will be conducted. Any damage will be promptly repaired. No facilities except <br />an empty water tank are located at the contractor staging area, so no effects are anticipated. The Okie Plaza Well will <br />not be undermined until a revision is approved by the Division for elimination or replacement of this monitoring well. <br />The underground workings to be undermined will be underground development entries. The No. 5 Mine mains and <br />sub -mains will be located over development entries (mains and sub -mains) of the No. 6 Mine. The No. 6 Mine <br />development entries are designed to remain stable for the life of the mine. These areas are protected against <br />subsidence damage by assuring that sufficient coal has been left in- place as pillars to prevent subsidence in these <br />areas. They are located outside the angle of draw of the planned mining. Therefore, there will be no subsidence <br />impact on the existing workings. <br />TR14-36 2.05-51 Revised 03/10/14 <br />