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t ` • • <br />William J. Carter December 1, 1998 <br />Re: 1998 Annual Subsidence Report <br />Also during 1997, the azea along the ridge between Hawksnest Creek and Bardine Canyon was <br />mined, as well as the lower elevations of Hawksnest Creek in the azea of projected longwall panel <br />number 1. The extreme eastern limit of mineable coal has been reached in these areas. Fourth, 5'~, <br />6'~, and 7's North were completed under the ridge. Pillars were extracted in 5~' North. Sixth and 7~' <br />North will become the gate entries for longwall panel number 2. Gate entries for longwall panel <br />number 1 encountered the rock split in the coal that defines the eastern mining limit. Combined with <br />the shortening of this panel by the mining limit, and the results of the ]ongwall subsidence evaluation <br />by Dr. John F. Abel, Jr., longwall panel number 1 will be mined by room and pillar methods. <br />During 1998 development of longwall panel gate roads continued throughout the year. Due to mine <br />ventilation conditions while waiting completion of the ventilation shaft, the eastern half of the mine <br />was temporarily sealed, and longwall panel development progressed in gate road entries of 18, 19, <br />20, and 2l North. Following completion of the ventilation shaft in July, the seals were breached and <br />development was started in 8'~ North. The longwall equipment was installed in the panel between 18 <br />and 19 North, and longwall mining began on August 26, 1998. <br />On August 31, September 8, September 14, September 21, September 29, October 5, October 12, <br />November 1, and November 30 visual inspections directly above the active longwall panel between <br />18 and 19 North were made. No visual indication of subsidence was evident during any of the <br />inspections. <br />On November 1, a final visual inspection of the pemrit area from Elk Creek to Thompson Creek was <br />made during part of the annual wildlife monitoring. No visible indication of recent mass movement <br />was apparent and no new mass movement features were noted during the inspection. <br />Sincerely, <br />~ (~ <br />Thomas C. Anderson, P.E. <br />Environmental Coordinator <br />2 <br />XBOw <br />