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B. Surface Monitoring <br />' Mirror data during the 2nd Quarter 2008 were collected between April and June, 2008. The #100 <br />Control Point on the site continues to show an average rate of displacement of about 0.023 <br />feet/year, or 0.27 inches/year. This rate is the same as that included in the 1 st Quarter 2008 Report. <br />' At Sylvester Gulch, the #50 Control Point showed consistent horizontal movement (about 0.5 feet <br />' since spring of 2005) and an uncharacteristic increase in vertical movement (about 5 feet over the <br />same time period). Consequently, the readings in Sylvester Gulch are questionable. <br />As stated in the last quarterly report, 16 mirrors were selected for monitoring at an increased <br />frequency of every two weeks during the spring and possibly summer months. The increased <br />frequency started with readings on March 27`h and 28''. <br />Furthermore, 12 new mirrors were installed on C-1 Conveyor. They are labeled 155 through 166. <br />Movement plots were not included in the last quarterly report because only the initial set of readings <br />had been collected at that time. Sufficient data now exist such that plots have been included in this <br />report. <br />¦ Main Mine Site Surface Mirrors <br />Increasing displacements were recorded during the 2nd Quarter 2008 at the following mirror <br />' locations: <br />' #3 & #89 Portal #1 <br />#134, #135 & #136 Slope Above Material Storage Bench <br />#130 & #131 MSB Access <br />t #97 S-1 Conveyor <br />#93 Toe of Slope, North of Micropiles <br />' For the most part, these locations were identified as showing increased displacement in the 1 st <br />Quarter 2008 Report. Mirrors #93 and #97 showed uncharacteristic jumps between the May and <br />' June readings. These mirrors will continue to be watched to see if the jumps are indicative of <br />increased movement or surveying errors. <br />The new mirrors on C-1 Conveyor are all generally moving together in a northeast direction and <br />have shown almost 2 inches of displacement since late March. The movements appear to be close to <br />the precision of the measuring instrument and they will continue to be watched closely. <br />Sylvester Gulch Surface Mirrors <br />Mirror data were collected in Sylvester Gulch during the 2nd Quarter 2008. The following mirrors <br />showed increasing displacements: <br />#3 <br />Barr Engineering Company <br />06/26-031 <br />West Slope Middle <br />2nd Quarter 2008 <br />Geotechnical Monitoring