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• 2008 Production and Geologic Conditions <br /> The Bowie No. 1 Mine suspended operations during December, 1997 and remained <br /> idle throughout the 2008 calendar year. <br /> Operation Unit Descriptions <br /> Bowie No. 1 Mine has no operating units to report on during the 2008 calendar year. <br /> Subsidence Impacts - 2008 <br /> Selected subsidence monitoring stations established over the Pitkin Mesa pipeline were <br /> monitored in June and December of 2008. <br /> Wide-Spaced Monitoring Grid Station Summary <br /> Through technical revision number 45, the DRMS approved a reduction in subsidence <br /> monitoring. The wide spaced subsidence monuments, Sites 6, 14, 15, 16, DH 55, DH <br /> 65, DH 66, DH 68, 81, 82, 83 and 95 were not monitored during 2008. <br /> Pitkin Mesa Pipeline <br /> Seven subsidence monitoring stations were established at locations along the Pitkin <br /> Mesa Pipeline which overlies Panel C. Panel C development commenced in October <br /> with twenty-four crosscuts completed by January 1, 1993. Panel C was mined utilizing <br /> a partial extraction design intended to preclude the development of subsidence in order <br /> • to protect the pipeline. The subsidence monitoring stations along the pipeline are <br /> depicted on Map No. 2-5. The stations were surveyed twice in 2008; June 24 and <br /> December 2. The results of this survey are appended to this report. The 2008 survey <br /> was conducted by Cragg Surveying. The Cragg survey will provide consistent survey <br /> values in the future, which will show that this area is stable. Surveys will continue <br /> approximately semi-annually until stability is documented. <br /> Visual Monitoring 2008 <br /> Visual subsidence monitoring is accomplished by periodic "walkovers" of recently mined <br /> areas within the present permit area. Walkovers are generally done in conjunction with <br /> survey monitoring due to the seasonal accessibility of the area. During the 2008 <br /> monitoring season, visual monitoring consisted of visual inspections done while <br /> performing survey monitoring and water monitoring. <br /> Visual monitoring is concentrated over areas of retreat mining with particular emphasis <br /> on areas mined under low overburden. Since the mine has now been idled in excess of <br /> 5 years, there are no areas of particular emphasis on which to concentrate visual <br /> inspections. <br /> Projected Subsidence Impacts -2009 <br /> Subsidence impacts during 2009 are projected to be minimal based upon subsidence <br /> patterns established to date. No mining is currently projected for 2009. <br /> 1 <br />