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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.