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Introduction <br />This report is for the period from January 1, 2011 through June 2011. Mine <br />Construction of the Bowie No. 2 Mine began during May of 1997, with coal production <br />beginning during August 1997. <br />The mining permit application for the Bowie No. 2 Mine requires the operator to submit <br />the results of the subsidence monitoring programs and the results of the visual <br />inspections of known modern and historic landslides within the permit and adjacent <br />area for stability in June and December of each year and report these results to the <br />Division within 30 days of the end of the reporting period. <br />The Operator is also required to inspect these landslides, both modern and historic, <br />monthly for six months immediately after retreat mining occurs. This same inspection <br />routine is applied to any spring or pond in the immediate proximity of retreat mining. <br />During the reporting period, mining continued in the 2 West Mains. The headgate and <br />tailgate for the B -10 Panel were completed. The B -10 longwall advanced approximately <br />500 feet and the tailgate for the B -11 Panel was advanced about 2000 feet. <br />Visual Inspection of known historic and modern landslides. <br />Because of limited mining advance during the first half of 2011, no visual inspections of <br />known historic and modern landslides were performed. <br />Increased Inspection activity associated with retreat mining. <br />Accessible subsidence cracks are repaired during coal exploration events and are <br />monitored by both coal exploration supervisors and hydrologic monitoring technicians. <br />No intensive survey of subsidence effects was performed during the period. Therefore, <br />Map 27 -C is not enclosed. During this period Spring 21 was potentially impacted or re- <br />impacted. Potentially impacted or re- impacted means the mine workings or angle of <br />draw of the mine workings passed under the monitoring point during the reporting <br />period. No influence to any hydrologic monitoring points was observed during this <br />period. <br />Results of Subsidence Survey Monitoring <br />The results of the May 2011 monitoring are attached. As in the past, the survey was <br />performed by Cragg Surveying using GPS methods. <br />Analysis of Subsidence Data <br />The following table presents an analysis of the subsidence survey data. Subsidence <br />survey requirements are shown on PAP pages 2.05 -163 and 164. Following is a <br />summary of the survey data collected during the period. <br />-2- <br />