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Note that the lower pit boundary has moved up hill into the <br />drainage, following the approximate outcrop of the Wadqe seam as <br />indicated on Photo A. This gives rise to the existing condition of <br />a backfilled pit which has no natural low wall on its downgradient <br />end and also corresponds to a relatively steep area of the mine <br />(e.g. drainage). Furthermore, a very active set of spoil springs <br />has developed in the area south of the Moffat pond as indicated in <br />photo A. As we talked, this would indicate that the area has some <br />capacity to "freely drain" possibly reducing the potential for a <br />build-up of pore-pressure. However, I am not sure whether this <br />"draining" is in a steady-state condition with any inflow or source <br />of water. <br />Furthermore, during July, I measured the water level in well 215E <br />located approximately as indicated in photo A. As noted in the <br />inspection report dated 7/20/95, 13 feet of water was found in this <br />lower Wadge well. Review of past monitoring indicates that this <br />July water level was: <br />* the highest water level since June of 1986 <br />* the highest July reading since July of 1985 <br />* the highest water level since Moffat mining began <br />* 3 feet higher than the baseline value recorded <br />Please be aware that the pit is still open and to some degree may <br />be acting as a pumping well. I would expect that once the pit is <br />reclaimed that the water levels may rise further, all other <br />conditions being equal. <br />My concern, as I expressed to you, is that given the increase in <br />spoil spring activity nearby, the lack of a low wall in this area, <br />and the somewhat dramatic rise in water level of the adjacent lower <br />Wadge well, this area may be unstable upon final reclamation. I <br />also believe that given the upcoming pit closure, evaluation of <br />possible mitigation to avoid this situation would be appropriate in <br />the near future. One possibility that crossed my mind would be to <br />bring the highwall onto the pit floor prior to pushing spoil into <br />the pit. This may help develop an underdrain that would assist in <br />draining the area. <br />I am requesting your formal opinion as to whether you concur that <br />a potential problem exists. As this mine is changing back to Susan <br />Burgmaier's lead, I wanted to document my concern before moving on <br />to other tasks. If you have questions or would like additional <br />info, let me know. <br />