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P9 also decreased from levels over the past four years. Only P6 showed an increase <br />over the maximum water levels in 2009 and 2008 and similar to 2007. This may also <br />due to silt built in the standpipe and will be monitored closely in 2011. <br />Based upon the 2010 monitoring data and embankment inspections, it appears that <br />the cutoff trench and clay blanket reconstruction performed in 2001 have addressed <br />the previous localized perched zone and related seepage through the embankment <br />core, thus, allowing the embankment to function as designed. <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 2010 report is provided in electronic Adobe Acrobat© Portable <br />Document Format on the CD attached to this report. <br />4.5 Waste Rock Dumps <br />The waste rock dumps were inspected monthly in 2010, except when winter <br />conditions prohibited access, in accordance with the recommended monitoring <br />program. As a result of the site manager's death, the water level measurements in <br />the rock dump piezometers were not documented until May. However, the historical <br />water levels in the piezometers show little fluctuations during the winter months. The <br />visual inspections conducted in 2010 indicate stable conditions for the Indian Creek <br />and Tie Camp waste rock dumps. <br />Once again in 2010, a few of the piezometers became plugged with silt and required <br />flushing with high pressure water to get the probe down to the water. Each <br />piezometer behaves differently and their flushing requires experience to be <br />successful. The water levels in the rock dump piezometers in 2010 continued to <br />show normal seasonal fluctuations when the silt was not an issue. Prior to October <br />2001, data was not obtained from Piezometer IC10600 due to the presence of a <br />gravel obstruction that blocked the passage of the piezometer. Additionally, in 2007, <br />the local elk herd destroyed the stand-pipe casing in Piezometer IC 10370 and <br />consequently caused the upper part of the borehole soil to collapse into the <br />piezometer casing. This resulted in approximately six feet of rock debris being <br />introduced into the bottom of the piezometer, rendering it non-functional until the fall <br />of 2009 when the obstruction was cleared from the bottom of the casing by high <br />pressure flushing. This allowed us to remedy that problem and to begin using the <br />Piezometer IC10370 as part of the monitoring system. Piezometer IC10300 was <br />also flushed in 2009 to remove the silt in the casing. This was a problem again in <br />Pitch Reclamation Project <br />Colorado Mined Land <br />Reclamation Board <br />2010 Annual <br />Reclamation Report <br />24