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i Introduction <br />This report is for the period from July 2010 through December 2010. Mine Construction <br />of the Bowie No. 2 Mine began during May of 1997, with coal production beginning <br />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 ends of the reporting periods. <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 />Mining of B-Seam rooms located west of the North Mains was completed during July. <br />Mining in the 1 st West Mains was completed during the period. During the last quarter <br />of the year Mining began in the 2 West Mains and the headgate and tailgate for the B- <br />10 Panel. <br />Visual Inspection of known historic and modern landslides. <br />• Because of limited mining advance during the second half of 2010, no visual <br />inspections of 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 no monitoring points were potentially <br />impacted or re-impacted. Potentially impacted or re-impacted means the mine workings <br />or angle of draw of the mine workings passed under the monitoring point during the <br />reporting period. No influence to any hydrologic monitoring points was observed during <br />this period. <br />Results of Subsidence Survey Monitoring <br />The results of the August, September and November 2010 monitoring are attached. As <br />in the past, the survey was performed by Cragg Surveying using GPS methods. <br />Analysis of Subsidence Data <br />The following table presents an analysis of the subsidence survey data. Following is a <br />summary of the survey data collected during the period. <br />• <br />-2-