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4.3.4 Geotechnical Program <br />A long term, time-domain-reflectometry monitoring program associated with well 4A-5M <br />showed no indication of subsidence in 2005. There has been no indication of subsidence from <br />this well since installation. Subsidence well (3M-TDR) was drilled late in 2003. Two of the four <br />TDR cables in 3M-TDR subsidence well appear to have water infiltration damage. In 2005 <br />readings were again taken and data was gathered from cables two and three. No significant <br />subsidence was detected in 3M-TDR. A change was noted (possibly the bottom 10-20 feet) in <br />cable 3 and verified by a third party instrument. Because cable 2 (located deeper in the well) <br />did not indicate change, it was concluded to be cable failure and not mining related damage. <br />These wells are located between cavities 5H, 6H, and 1A. As a result of only two cables <br />working in 3M-TDR, per the monitoring plan, logging was performed. <br />Well 3M-TDR provides access for additional geotechnical logging information in an area <br />adjacent to extensive cavity mining. In 2005, CCL and temperature logs were performed on <br />3M-TDR indicating no ground movement and continued decrease in temperature (220 to 158 <br />degrees F) following re-completion in 2003 to 2005. Subsidence wells 94-1 M and 88-1 were <br />also logged with no ground movement noted, wells indicated continued elevated temperatures <br />due to previous mining. <br />is- <br />