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B. Surface Mirrors <br />Main Mine Site Surface Mirrors <br />Portal #1: <br />Increases in movement at mirrors #3 and #89 were recorded during the 2°d quarter 2006. Although <br />this movement is down on the maximum displacement measured at these two locations during <br />2005, a generally increasing displacement trend is noticed. <br />These mirrors should continue being monitored in subsequent months of 2006. The movement <br />correlates well with increased ground water levels measured at this location as discussed in Section <br />A. It is recommended that the horizontal drains located in this azea be cleaned out with a high <br />pressure hose to ensure that debris is not restricting their drainage capacity. <br />Material Storaee Bench: <br />Mirror #130 located along the MSB access road is continuing to show increasing rates of <br />displacement. This mirror has accumulated almost 0.5 feet of movement during 2006. in addition, <br />the mirrors #134, #135 and #136 located above the MSB aze showing increasing displacements <br />during the 2°d quarter 2006. Movements in this area are totaling 6, 18 and 12 feet respectively.. <br />It is suggested that this movement is correlated to pooling ground water within the fill and <br />t colluvium material on the MSB as a result of ground water flowing through the neaz surface <br />colluvium (from above -causing instability also) and underlying F-Coal seam that both dischazge at <br />this location. An engineering design for a dewatering trench at the MSB that will help alleviate the <br />' high ground water levels, and subsequent movement at this location is cuarently under review by <br />MCC. <br />' Micro Piles• <br />Mirror #112 has shown a significant increase in the movement measured during the 2nd quarter <br />' 2006. However, based on the historical monitoring data, this movement is expected to "bounce <br />back" during the second half of 2006. This mirror is located in an area of the main landslide that is <br />currently experiencing elevated ground water levels. It is recommended that this mirror and the <br />' piezometers in this azea (as discussed in Section A) be monitored in both the 3'd and 4`" quarters <br />2006. <br />Cl Convevor• <br />Mirrors #144 and #141 are showing increasing rates of displacement and since the 4's quarter, 2005 <br />movement of these mirrors has totaled approximately .OS feet. This azea is critical to the operations <br />at the mine, and its stability will be reviewed during the 2006 annual structural inspection to <br />determine if any remedial action is required to ensure the safe and continua] operation of mine <br />infrastructure. <br />Barr Engineering Company 2n° Quarter 2006 <br />06/26-031 Geotechnical Monitoring <br />