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• 2.05.6(6) <br />No pre-subsidence survey is proposed for the power line support towers <br />located along Terror Creek because they are located in a limited extraction <br />zone. A pre-subsidence survey has been done for Bruce Park dams, see <br />Volume X. The pre-subsidence survey consists of a Geotechnical Data <br />Report for the Bruce Park Dam and an Addendum to that report both <br />presented in Volume X. The geotechnical reports present geologic mapping <br />and subsurface geotechnical data for the main dam and saddle dam. An <br />additional pre-subsidence inspection of the Bruce Park dams, Bruce Park <br />Landslide and the surrounding area was preformed by YEH and Associates, <br />Inc. during 2007. Their report is presented in Volume IIIA, Tab 22. <br />(f)(v)(B) Monitoring <br />See tables on pages 2.05-121 and 2.05-122. <br />The hydrologic monitoring program will continue. At least quarterly <br />monitoring will be performed. Surface streams, ponds, springs and <br />groundwater will continue to be monitored. The results of the monitoring will <br />be observed for abrupt changes in water levels, flows or quality which might <br />indicate mining impact. <br />The Operator has set up a subsidence network over the first five B-Seam <br />longwall panels to gain as much information as possible to compare actual <br />data with the subsidence predictions presented in Volume IIIA, Exhibits15, <br />17 and 21. Additionally, the actual subsidence data will be utilized to check <br />the design and effectiveness of limited extraction zones. <br />At the request of the DRMS and UDSA-FS the Operator installed eight <br />subsidence monuments in the limited extraction zone along Hubbard Creek <br />(monuments 17-A through 17-H). These monuments will be utilized to verify <br />that subsidence does not occur along the limited extraction zone. Six of the <br />monuments were installed during 2001 prior to the November 2002 longwall <br />start-up in panel D-7. Two of the monuments 17-G & 17-H will be installed in <br />2009 prior to the initiation of mining in Panel B-9. At the request of the <br />DRMS the Operator has identified twenty (20) subsidence monuments to <br />• measure settlement over superimposed multi-seam extraction as follows: <br />TR-65 2.05 - 118 - 12/09