2009-08-07_REPORT - C1996083 (2)

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Introduction This report is for the period from January 2009 through June 2009. Mine Construction of the Bowie No. 2 Mine began during May of 1997, with coal production beginning during August 1997. The mining permit application for the Bowie No. 2 Mine requires the operator to submit the results of the subsidence monitoring programs and the results of the visual inspections of known modern and historic landslides within the permit and adjacent area for stability in June and December of each year and report these results to the Division within 30 days of the ends of the reporting periods. The operator is also required to inspect these landslides, both modern and historic, monthly for six months immediately after retreat mining occurs. This same inspection routine is applied to any spring or pond in the immediate proximity of retreat mining. No longwall mining occurred during the period. The 2"d East Mains were completed during the period. Development for the B-8 panel was nearing completion by the end on the reporting period. Development of the B-9 headgate and tailgate were ongoing at the end of the reporting period. Visual Inspection of known historic and modern landslides. A visual inspection of all known historic and modern landslides was conducted during June, 2009 by Brad Lindsay, Rock Logic Consulting LLC. Mr. Lindsay's report is attached. No new subsidence cracks were noted. Increased Inspection activity associated with retreat mining. Accessible subsidence cracks are repaired during coal exploration events and are monitored by both coal exploration supervisors and hydrologic monitoring technicians. The accessible visual results of the subsidence effects associated with the Bowie No. 2 Mine are overlain on Map 27-C Subsidence Features. Map 27-C is enclosed. During this period springs 34-10, 34-22, 34-23 and 34-25 were impacted or re-impacted by the development of the D-8 panel. Potentially impacted or re-impacted means the mine workings or angle of draw of the mine workings passed under the monitoring point during the reporting period. No influence to any hydrologic monitoring points was observed during this period. Results of Subsidence Survey Monitoring The results of the May and June 2009 monitoring are attached. As in the past, the survey was performed by Cragg Surveying using GPS methods. Analysis of Subsidence Data The following table presents an analysis of the subsidence survey data. Following is a summary of the survey data collected during the period. Development of the B-8 panel occurred near Hubbard Creek and Dove Gulch. -2-