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Pitch Reclamation <br />Project Colorado Mined <br />• Land Reclamation Board <br />2006 Annual Reclamation <br />Report <br />4.4 Sediment Control Embankment <br />The safety and efficiency of the sediment embankment is monitored with a network <br />of surface and subsurface systems. There are five (5) permanent survey <br />monuments where any physical movement of the embankment can be measured <br />and nine (9) piezometers have been installed to monitor the phreatic surface within <br />the embankment. Five of the piezometers were installed during the initial <br />construction in 1980, and four of the piezometers were completed in the core of the <br />embankment in 2001. The 2006 monument survey was performed on October 1 <br />and results indicate the amount of vertical movement is minimal and within the range <br />of survey error. No significant vertical displacement has occurred since the initial <br />settlement following construction. <br />Snow melt in the spring of 2006 was substantially down as compared to 2005, when <br />water stored in the sediment pond reached an elevation of 9893.5 ft amsl (6.5 ft <br />below the spillway). During 2006, the maximum water elevation in the pond was <br />recorded at 9889.5 ft. amsl with the average elevation maintained at 9884.9 ft amsl. <br />Seepage that was observed on the downstream face of the embankment in June <br />2000, and discussed in the 2000 and 2001 annual reports, has not reappeared <br />following the repair work conducted in 2001. The monuments and piezometers will <br />continue to be monitored in 2007. <br />A Sediment Embankment Report is submitted annually to the Colorado Division of <br />Water Resources (CDWR) providing the results of the embankment-monitoring <br />program. The 2006 report is provided in electronic Adobe Acrobat© Portable <br />Document Format on the CD attached to this report. <br /> <br />4.5 Waste Rock Dumps <br />The waste rock disposal areas were inspected monthly during 2006, except when <br />winter conditions prohibited access, in accordance with the recommended monitoring <br />program. Inspection results indicate stable conditions for the Indian Creek and Tie <br />Camp Creek waste rock dumps. Seven (7) piezometers were measured monthly to <br />monitor seasonal phreatic surface fluctuations for both the Indian Creek and Tie <br />Camp waste rock dumps. The piezometer measurement results indicate normal <br />seasonal fluctuations in the depths to water similar to those observed in past years. <br />Following the dry conditions of 2001 through 2004, the seasonal fluctuations <br />18 <br />