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Pitch Reclamation Project <br />Colorado Mined Land <br />Reclamation Board <br />2008 Annual <br />Reclamation Report <br />likely a result of snowmelt and runoff from surrounding sources originating between the <br />Pinnacle plug and the PP-01 monitoring point. Once the snowmelt period is over the <br />flow rate at PP-01 decreases and stabilizes at normal levels. <br />4.3.4 Radium and Uranium Concentrations at PP-01 <br />Dissolved radium 226 and total uranium have been monitored at PP-01 since March <br />1994. After construction of the Pinnacle Adit plug in September 1995, both the <br />dissolved radium 226 and total uranium concentrations have stabilized at reduced <br />concentrations. A graph of the radium and uranium concentrations at PP-01 is <br />provided as Figure 6. During 2008, total uranium and dissolved radium 226 levels <br />remained at the reduced concentrations observed over the preceding twelve-year <br />period. <br />4.4 Sediment Control Embankment <br />The safety and efficiency of the sediment embankment is monitored with a network of <br />surface and subsurface systems. There are five (5) permanent survey monuments <br />where any physical movement of the embankment can be measured and nine (9) <br />piezometers have been installed to monitor the phreatic surface within the <br />embankment. Five of the piezometers were installed during the initial construction in <br />1980, and four of the piezometers were completed in the core of the embankment in <br />2001. The 2008 monument survey was pertormed on October 24 and results indicate <br />the amount of vertical movement is minimal and within the range of survey instrument <br />error. No significant vertical displacement has occurred since the initial settlement <br />following construction. <br />Because of the increase in the snow pack and higher runoff in 2008, the piezometers <br />in the embankment were monitored more frequently during the peak snow melt in late <br />May and June. The water level of Piezometer P1 in the upstream face of the <br />embankment fluctuated with the increase in the pond level, increasing in late May, <br />falling back to normal levels as the pond water level decreased by mid-July. Seepage <br />observed on the downstream face of the embankment in June 2000, and discussed in <br />the 2000 and 2001 annual reports, has not reappeared following the repair work <br />conducted in 2001. In 2008, during peak runoff, Piezometers P3 and P4 deviated from <br />historic levels then fell back to normal levels by the end of June. The water level in <br />Piezometer P4 has risen from an average water level elevation of 9832.7 ft. amsl, and <br />a maximum water level elevation of 9835.3 ft. in 2005 to an average water level of <br />9833.0 and a maximum water level elevation of 9837.7 in 2006. The average water <br />• <br />10 <br />