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period, as shown on Table 1. By comparison, 41 points had annual displacement <br />magnitudes greater than survey error for the 2009-2010 monitoring period. Of the <br />13 additional monuments that were added in 2005 to monitor the slide at the east <br />wall of the south pit, 8 showed displacement greater than survey error. Velocity <br />vectors were calculated for the 31 points and are depicted with green circular <br />symbols and velocity vectors on the Slope Displacement Vectors drawing presented <br />as Appendix A. Points with a displacement less than the survey error are shown in <br />gray on the map. All monitoring points are shown on the summary table located on <br />the Slope Displacement Vectors drawing presented as Appendix A. Displacement <br />for monitoring points where displacement was not detected, or was less than <br />calculated survey error is indicated as "ND" or non-detectable (SRK Consulting Inc. <br />2011). <br />Slope displacements for the monitoring points within survey error during the 2009 - <br />2010 monitoring period have either decreased, or consistent with the displacements <br />observed during the 2008 - 2009 period. The current displacements for all the <br />monitoring stations were, on average, approximately 5% less than the displacements <br />during the previous monitoring period. From previous reports, the 2007 - 2008 <br />period saw an increase in displacement which was possibly a result of a higher than <br />average rainfall over that period. The increased displacement was observed <br />primarily in the northeast corner of the north pit and the small slump feature above <br />the east wall of the south pit. The current maximum displacement at the northeast <br />corner of the north pit is 0.42 ft/year at MP-69, which had a displacement of 0.62 <br />ft/year during the previous monitoring period. Displacement at the slump above the <br />east wall of the south pit also appears to have slowed. At the slump, the current <br />maximum displacement is 1.00 ft/year at monitoring point S-4, which had a <br />displacement of 0.72 ft/year during the previous monitoring period. <br />During 2008, repairs were made to improve drainage at the slump above the east <br />wall of the South Pit. In the fall of 2010, additional survey monitoring points were <br />added in the South Pit, and some were replaced because they were compromised by <br />slope movement, resulting in a net gain of 2 monitoring points. Also in 2010, the <br />tension cracks were graded closed on the bench and on parts of the slope adjacent <br />to the bench that were accessible to the backhoe. The bench was also crowned <br />longitudinally across the slump to promote drainage. These maintenance measures <br />will be continued as needed to optimize drainage from the area of slope <br />displacement. <br />Pitch Reclamation Project <br />Colorado Mined Land <br />Reclamation Board <br />2010 Annual <br />Reclamation Report <br />17