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1 Pitch Reclamation Project March 2003 <br />2002 Annual Reclamation Report Page 3 <br />' 3.1 Revegetation and Regrading <br />The site of the RTP was backfilled and recontoured in 2001 with final grading and revegetation in <br />2002. The steep embankment behind the RTP site was graded to reduce the slope and prevent <br />sloughing. A total of 1,000 lodgepole pine and 200 spruce trees were planted on the recontoured <br />area formerly occupied by the RTP. An illustration of the planting activity is provided in Figure 2. All <br />' work was conducted in accordance with applicable conditions in the Radioactive Materials License <br />and the Pitch Reclamation Project Procedures Manual. <br />4.0 MONITORING AND ANNUAL REPORTING <br />4.1 Slope Movement Vector Analysis <br />Survey monuments have been installed on the east and south walls of the North Pit to monitor <br />surticial slope movement. For clarity in this report, the area east of the pit lake and south of <br />Northing 113,500 is referred to as the south wall of the North Pit; and the area east of the pit- lake <br />and north of Northing 113,500 is referred to as the east wall of the North Pit. This differentiation is <br />for ease in discussing slope movement and does not imply that there is a kinematic distinguishing <br />feature at this location. The original group of monitoring points was installed in 1994 with additional <br />monitoring points established in 1996, 1997, 1998, and 1999. No new monuments have been <br />installed since 1999. Monument locations are provided on the Slope Velocity Vectors Map <br />presented in Appendix A. Surveys are usually conducted as close to one year apart as possible, <br />allowing the magnitude of displacement to be reported as a velocity in terms of ft/year. <br />Surveys of all accessible monuments were conducted on July 11, 2001 and September 20, 2002. <br />Although the survey interval is greater than one year, slope movement is not typically observed in <br />the late summer months, so the data should be representative of annual displacement. Of the 61 <br />points surveyed in both years, only 12 had magnitudes that were greater than survey error, as <br />shown on Table 1. By comparison, 37 points had magnitudes greaterthan survey error reported in <br />2001. Velocity vectors were calculated for the 12 points and are depicted with green circular <br />symbols and velocity vectors on the Slope Velocity Vector Map provided as Appendix A. Points with <br />a displacement less than the survey error are shown in gray on the map. <br />All the total displacement values are less than or equal to 0.26 ft/year. The lack of measurable <br />slope displacement data suggests that the stability of the North Pit slopes has stabilized to less than <br />0.5 ft/year. The reduced displacement rates are most probably related to the additional soil material <br />placed at the toe of the East Wallin 1996 and decreased groundwater levels in response to several <br />years of relatively low precipitation. It is possible that in future years with above average <br />precipitation, some increase in displacement may occur due to saturation ofthe slopes. However, it <br />is anticipated that any increased displacement would be in the range of one-half foot per year. <br />Overall, the potential for catastrophic failure remains extremely low. <br />2002_ RECLAMATION RPT.DOC <br />