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Pitch Reclamation Project <br />Colorado Mined Land <br />Reclamation Board <br />is 2009 Annual <br />Reclamation Report <br />The intention of the plug was to partially seal the Pinnacle Adit and allow the area <br />around the mine workings to resaturate. The resaturation of the workings was <br />expected to re-establish a geochemically reducing environment and lower the solubility <br />of uranium and radium within the underground workings of the Pinnacle Mine. The <br />Division's approval of TR4, required Homestake to monitor the effects of resaturation in <br />the Pinnacle workings for five years or until hydrologic conditions stabilized. <br />Components in the Monitoring Plan outlined in TR4 (Section 4.0), included <br />continuation of discharge water quality monitoring at the POC (SW-33), monitoring of <br />groundwater resaturation levels, annual spring and seep surveys in areas down- <br />gradient from Pinnacle workings, and monitoring for changes in water quality that could <br />be attributable to resaturation. The stated purpose of the monitoring program is to <br />verify the intended effectiveness of the adit plug. Homestake has continued to monitor <br />the following facets of resaturation through 2009: <br />• Survey of springs and seeps; <br />• Groundwater levels in piezometers installed in the area of the Pinnacle <br />workings; <br />• Water quality and flow from the Pinnacle Adit at sampling point PP-01; and <br />• Monitor discharges from the property at the CDPS permit POC SW-33. <br />As in 2009, monitoring the resaturation of the south wall of the North Pit will continue <br />in 2010. <br />4.3.1 Spring and Seep Monitoring <br />Spring and seep surveys were conducted to monitor changes in shallow groundwater <br />conditions due to construction of the Pinnacle Adit plug. These surveys have been <br />conducted annually since July 1995 and were repeated in 2009. In general, flow from <br />some springs and seeps increased for a brief period after the adit plug installation and <br />have declined to a steady state since the spring of 1997. Small variances noted since <br />1997, are believed to be attributable to a variety of conditions including precipitation, <br />depth of snow pack, timing of snowmelt, and the potential for infiltration with respect to <br />frozen ground. All "active" spring and seep locations are shown in Figure 3. Springs <br />and seeps currently designated as "inactive" (no flow or seepage observed over the <br />past five years) are not shown, but can be found on maps issued with past reports. A <br />new spring (IC-12) was found and monitored in 2008. Its flow rate was consistent with <br />the other springs. Table 2 shows spring and seep data, including flow measurements, <br />from 1995 to the present. <br />10