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Introduction <br />This report is for the period from January 1, 2013 through June 30, 2013. 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 prior reporting period, mining was completed in the 2 West Mains. The 2 <br />West Mains turn into the B -15 headgate which was advanced about 300 feet. The B -14 <br />headgate was completed and the B -13 panel was mined out. The B -16 headgate was <br />advanced about 2,000 feet. Mining to the north in the 2 North Mains began during the <br />period with a advance of about 350 feet in two entries. <br />Visual Inspection of known historic and modern landslides. <br />A visual inspection of all known historic and modern landslides was conducted during <br />May and June 2013 by Brad Lindsay, Rock Logic Consulting LLC. Mr. Lindsay's report <br />is attached. Twelve cracks were observed. Most of the newly identified cracks overlay <br />the B -13 panel. Many, but not all the cracks roughly follow the surface topography. <br />Cracks were found on steep surfaces, along ridge lines and in flat meadows and range <br />from less than an inch to 24 inches wide. Cracks over the B -10, B -11 and B -12 panels <br />continue to heal. <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 />During the period Springs 7 -9, 7 -10 and 8 -5, Pond and Spring 20 and 7 -1 and Pond 18- <br />1 and 83 were potentially impacted or re- impacted. Potentially impacted or re- impacted <br />means the mine workings or angle of draw of the mine workings passed under the <br />monitoring point during the reporting period. No influence to any hydrologic monitoring <br />points was observed during this period. <br />Results of Subsidence Survey Monitoring <br />The results of the May and June 2013 monitoring are attached. As in the past, the <br />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. Subsidence <br />-2- <br />