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Pitch Reclamation Project Colorado Mined Land Reclamation Board 2009 Annual Reclamation Report ,4.0 MONITORING AND ANNUAL REPORTING 4.1 Slope Movement Vector Analysis Survey monuments were installed at the Pitch Reclamation Project to monitor surficial slope displacement in both the North and South pits. The area east of the North Pit Lake and south of Northing 113,500 is referred to as the south wall of the North Pit; and the area east of the pit lake and north of Northing 113,500 is referred to as the east wall of the North Pit. These walls are identified separately for ease in discussing slope movement and do not imply the presence of a kinematic distinguishing feature at this location. The first group of monitoring points were installed at the east and south walls of the North Pit in 1994. Some of the monuments have been destroyed due to re-grading, while critical ones were replaced with new monuments having different identification numbers. In 1996, six monitoring points were installed to replace points in the North Pit. In 1997, 14 monitoring points were installed to monitor shallow slope movement that was observed on the south wall of the North Pit. In 1998 and 1999, five monitoring points were installed at existing locations including inclinometer collars. In 2000, 11 monitoring points were installed in the North and South pits. A monitoring point was placed at the collar of piezometer P-09 at the east wall of the South Pit in 2001. In 2005, 13 monitoring points were installed to monitoring shallow slope displacement observed on the east wall of the South Pit. There are currently 83 monitoring points in the North and South pits to monitor surficial slope movement. Monument locations are provided on the Slope Displacement Vectors drawing presented in Appendix A. Surveys are usually conducted as close as one year apart as possible, allowing the magnitude of any displacement to be reported as a velocity in terms of ft/year. Surveys of all accessible monuments were conducted on September 28, 2009 with the previous survey performed on October 24, 2008. The surveys are actually conducted over several consecutive days with the median date used to represent the data set. Of the 81 points surveyed in 2009, 41 had annual magnitudes that were greater than survey error during the 2008-2009 monitoring period, as shown on Table 1. By comparison, 47 points had annual magnitudes greater than survey error for the 2007- 2008 monitoring period. Of the 12 additional monuments that were added in 2004 to monitor the slide at the east wall of the South Pit, seven showed displacement greater than survey error. Velocity vectors were calculated for the 41 points and are depicted with green circular symbols and velocity vectors on the Slope Vector Map (Appendix A). Points with a displacement less than the survey error are shown in gray on the 7