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has presented a subsidence control plan to repair or mitigate damage caused by subsidence for each of the <br />existing structures. Details regarding the subsidence control plan may be found in the approved PAP. A brief <br />summary of the subsidence control measures for each structure follows. <br />County Road No. 33 <br />Mining conducted in the Eastern Mining District (EMD) and longwall panel 12 in the Northern Mining <br />District (NMD) undermined portions of Routt County Road No. 33. TCC conducted daily monitoring of the <br />road when the longwall panels were approaching and undermining the road. When surface observations <br />found the asphalt road surface had buckled or been damaged due to subsidence, TCC temporarily repaired <br />the surface using gravel. Once subsidence monitoring indicated that subsidence had ceased, a permanent <br />asphalt overlay or patch was applied to the damaged road section. This method was successfully used during <br />the mining of Longwall panels 9R, 8R, 7R, 6R and 5R in the Eastern Mining District, and Longwall panel <br />12R in the Northern Mining District. Twentymile Coal Company re-paved segments of Routt County Road <br />No. 33 in the fall of 1999, that had experienced damage due to subsidence of Longwall Panels 5R and 6R. <br />Twentymile Coal Company scaled loose rock from the slope above Routt County Road No. 33 prior to <br />undermining Longwall panel 12R, and placed temporary concrete barriers or chain link meshing along the <br />north side of Routt County Road No. 33, to ensure that rockfall would not reach the road. <br />Union Pacific Railroad <br />When daily monitoring indicates that the track is damaged or the grade has changed, a slow speed restriction <br />will be instituted. Re-leveling and repair of the track occurred in accordance with mitigation plans required <br />by Union Pacific Railroad. <br />Hayden-Gore Pass Powerline <br />TCC notified the utility company 30 days prior to undermining the powerline in addition to the Division's <br />requirement to provide six months notification prior to undermining. TCC monitored the powerline <br />structures daily. The powerline was subsided without interruption or significant damage to the powerline <br />towers. Power company personnel inspected the powerline after subsidence had occurred and found that <br />deformation of the structures was within company specifications and did not require Twentymile Coal <br />Company to conduct repairs. Information regarding subsidence of the Hayden-Gore powerline can be found <br />in the 1997 and 1998 Subsidence Reports. <br />Archer-Hayden _Powerline and Western Area Power Administration and Tri-State and Public Service <br />Powerlines <br />A monitoring plan for the Archer-Hayden powerline was approved by the powerline operator and <br />incorporated into Exhibit 7e-7 of the PAP. No significant damage or interruption of power was experienced <br />during the subsidence of the Archer-Hayden, Western Area Power Administration and Tri-State and Public <br />Service powerlines. <br />Twentymile Coal Company proposes to subside portions of two powerlines with Western Mining District <br />Longwall panels 13L, 14L, 15L, 16L, and 17L in Township 5 North, Range 87 West, Sections 23 and 26. <br />Twentymile Coal Company has undermined and subsided powerlines in the EMD and NMD without any <br />significant damage or disruption of service. Twentymile Coal Company anticipates the powerlines overlying <br />Longwall panels 13L through 17L shall react in the same manner. <br />24