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monitoring program is to verify the intended effectiveness of the adit plug. <br />Homestake has continued to monitor the following facets of resaturation through <br />2010: <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 2010, monitoring the resaturation of the south wall of the North Pit will continue <br />in 2011. <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 2010. In general, flow <br />from some springs and seeps increased for a brief period after the adit plug <br />installation and have declined to a steady state since the spring of 1997. Small. <br />variances noted since 1997, are believed to be attributable to a variety of conditions <br />including precipitation, depth of snow pack, timing of snowmelt, and the potential for <br />infiltration with respect to frozen ground. All "active" spring and seep locations are <br />shown in Figure 3. Springs and seeps currently designated as "inactive" (no flow or <br />seepage observed over the past five years) are not shown, but can be found on <br />maps issued with past reports. A new spring (IC-12) was found and monitored in <br />2008. Its flow rate was consistent with the other springs. Table 2 shows spring and <br />seep data, including flow measurements, from 1995 to the present. <br />4.3.2 Groundwater Levels <br />Seven piezometers were installed in the area of the Pinnacle Mine to monitor the <br />piezometric surface within the workings area behind the adit plug. The piezometers <br />are identified as P4 through P10. Piezometer P7 was installed as a replacement for <br />P6, which was lost during plug grouting/construction. The locations of these <br />piezometers are provided in Figure 3. All six piezometers fluctuate seasonally with <br />the highest levels in late May or early June sympathetic with snowmelt. A hydrograph <br />of the piezometer water levels is provided as Figure 4. It should be noted that the <br />Pitch Reclamation Project <br />Colorado Mined Land <br />Reclamation Board <br />2010 Annual <br />Reclamation Report <br />20