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-2- <br />Introduction <br />This report is for the period from July 1, 2015 through December 31, 2015. Mine <br />Construction of the Bowie No. 2 Mine began during May of 1997, with coal production <br />beginning during August 1997. <br /> <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 area <br />for stability in June and December of each year and report these results to the Division <br />within 30 days of the end of the reporting period. <br /> <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 /> <br />During the reporting period, mining was completed in panel B-17. Development in the <br />north mains continued during the period. The north mains were advanced about 480 <br />feet. Panel 18 tailgate was advanced approximately 2,000 feet. <br /> <br />Visual Inspection of known historic and modern landslides. <br />A visual inspection of all known historic and modern landslides was conducted during <br />November 20, 2015 by Brad Lindsay, Rock Logic Consulting LLC. Mr. Lindsay’s report <br />is attached. One new crack was observed over Panel B-17. <br /> <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 />Spring 6-6 was potentially impacted by Panel B-17during July 2015. Pond 6-5 was <br />potentially impacted by the B-18 headgate during October 2015. Potentially impacted <br />or re-impacted means the mine workings or angle of draw of the mine workings passed <br />under the monitoring point during the reporting period. No influence to any hydrologic <br />monitoring points was observed during this period. <br /> <br />Results of Subsidence Survey Monitoring <br />The Pitkin Mesa Pipeline surveys were conducted in September and November. <br />Monitoring points PL-11 and PL-12 which are located over panel 15 showed some <br />addition downward movement. The Terror Creek and Terror Creek transmission line <br />tower survey was performed June. The transmission line towers were not surveyed <br />during the second quarter. Monitoring results are attached. As in the past, the survey <br />was performed by Cragg Surveying using GPS methods.