2013-10-17_PERMIT FILE - C1982056A (4)

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11. After the 19 -Right Longwall Panel has been completed, visual inspections and postmining instrument surveys will be performed on a once - monthly basis for an additional three months. After this three month period, and if visual inspections and instrument surveys show no further subsidence, the monitoring program for the 19 -Right Panel will cease. 12. A daily report will be forwarded to the representative of the owners of the powerlines. A 69KV powerline, owned by Yampa Valley Electric Association, parallels RCR27. This powerline is supported on wooden "H" structures, and will be visually inspected on a daily basis for indications of differential settling, or any damage to poles, cross -bars, or components. Inspections will commence when longwall mining approaches within 500 feet of the nearest structure and will continue until the longwall face is approximately 1,000 feet past the structures. Union Pacific Railroad (formerly Denver & Rio Grande) - Monitoring of the track overlying Panels 17- and 18 -Right will commence once the longwall face is within 300 feet of the track, and it will continue until the face is 1,500 feet past the track. The monitoring will include surveying track elevations and coordinates at points on the rail, and surveying monuments located adjacent to the track. In the event there are grade changes which could disrupt rail traffic, the railroad tracks will be repaired accordingly. The anticipated repair would focus on re- leveling the track and /or having a slow -speed restriction during the time period that the track is affected. Monitoring and repair of the track will occur until mining of Panels 17- and 18 -Right of the NMD have been completed. Fish Creek and the Associated AVF — Fish Creek will be surveyed before and after mining of Panels 17- and 18 -Right to define the premining and postmining channel profiles. The postmining profile will be compared with the baseline (premining) survey information to determine if there are unanticipated changes resulting from the undermining of the creek. The surveys will be performed during low -flow periods prior to and following completion of mining. In addition to surveying premining and postmining longitudinal profiles, TCC will survey any major pool areas that develop over the panels. TCC will utilize the hydrologic monitoring plan presented in Exhibit 4e -8 to assess any impacts from subsidence on Fish Creek. In general, the details of the plan are as follows: The monitoring plan will utilize alluvial wells and surface water monitoring sites as upstream and downstream sites. For example, existing upstream sites AVF -13 and SW -13 will continue to operate as the upstream sites. Surface Site SW -15 and associated Well AVF -15 will be lost following the mining of the 17 -Right Longwall Panel. Existing surface Site 305 and associated alluvial Well 008 -AU 3, will replace SW -15 and AVF -15, respectively as the new downstream monitoring locations. Alluvial Well 008 - AU -3 will be monitored quarterly for water level and field parameters, and semi - annually for full -suite water quality parameters (Exhibit 14 -6). Surface Site 305 will be monitored monthly for flow (March through September), and semi - annually for field parameters and full -suite water quality parameters. The results of stream surveys and ongoing monitoring will be incorporated into the appropriate semi - annual subsidence reports. Given that premining and postmining surveys and ongoing monitoring during undermining of Fish Creek fully confirmed projections of both subsidence and related effects on Fish Creek for the NMD, TCC is not proposing further surveys for affected portions of Fish Creek in the WMD. As part of the ongoing hydrologic monitoring program, however, TCC will monitor flow and water quality upstream and downstream of the WMD at Surface Site 16A and Alluvial Well 006 AY -1, and Surface Site SW13 and Alluvial Well AVF -13, respectively. The results of the relevant ongoing hydrologic monitoring will be incorporated into the appropriate semi - annual subsidence reports. Stock Ponds - Stock ponds that fall within the projected subsidence area(s) will be inspected prior to and following completion of the mining in the corresponding area(s), for any evidence of damage or changes in configuration. Any cracks in the pond embankments or catch basins will be repaired and any obvious changes in pond configuration will be addressed through repairs or reconstruction, as appropriate. PR09 -08 2.05 -191.7 04/29/09