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Introduction <br />This report covers the 200 period from July 2001 through December 2001. Mine Construction of <br />the Bowie No. 2 Mine began during May of 1997, with coal production beginning during August <br />1997. Some additional information concerning the first half of 2002 is also included. <br />The mining permit application for the Bowie No. 2 Mine requires the operator to submit the <br />results of the subsidence monitoring programs and the results of the visual inspections of known <br />modern and historic landslides within the permit and adjacent area for stability in June and <br />December of each year and report these results to the Division within 30 days of the ends of the <br />reporting periods. <br />The operator is also required to inspect these landslides, both modern and historic monthly For <br />six months immediately after retreat mining occurs. This same inspection routine is applied to <br />any spring or pond in the immediate proximity of retreat mining. <br />Visual Inspection of known historic and modem landslides. <br />A visual inspection of all known historic and modern landslides was conducted during November <br />2001 by David A. Jenkel, 2768 Compass Drive, Suite 101, Grand Junction, CO 81506. No new <br />or rejuvenated landslides were found during this inspection. These sites aze regulazly inspected <br />by Bowie personnel during gob vent borehole construction and reclamation efforts. <br />Increased Inspection activity associated with retreat mining. <br />Photographs of the more recent subsidence cracks aze attached to this report. Accessible <br />subsidence cracks were repaired during coal exploration events and are monitored by both coal <br />exploration supervisors and hydrologic monitoring technicians. The accessible visual results of <br />the subsidence effects associated with the Bowie No. 2 Mine aze overlain on Map 27 - <br />Subsidence which is attached to this report. During this period, 18 hydrologic monitoring points <br />were impacted or re-impacted by mining activities. Four of these sites were monitoring wells, <br />two of which were destroyed. Twelve of the points were springs, of which only 4 (S-4, S-4a, S- <br />5, S-Sa) aze consistent producers of water. Two of the points are man-made ponds associated <br />with the four producing springs, Pond 4 and Pond 5. No impacts to any of these hydrologic <br />monitoring points were observed during this period (other than the destruction of DH-57 and <br />DH-57a. <br />Results of Subsidence Survey Monitoring <br />The results of the November 2001 monitoring aze attached. As in the past, the survey was <br />performed by Cragg Surveying using GPS methods. <br />