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Pitch Reclamation <br />Project Colorado Mined <br />Land Reclamation Board <br />2006 Annual Reclamation <br />Report <br /> <br />I • <br />quality that could be attributable to resaturation. The stated purpose of the <br />monitoring program was to verify the intended effectiveness of the adit plug. <br />Homestake has continued to monitor the following facets of resaturation through <br />2006: <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 Point-of-Compliance SW-33. <br />In 2007, Homestake will continue to monitor the resaturation of the south wall of the <br />North Pit as done in 2006. <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 2006. 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 />presented in Figure 3. Locations of springs and seeps currently designated as <br />"inactive" (not observed over the past five years) have been removed from Figure 3. <br />Locations of inactive springs and seeps can be found on maps issued with past <br />reports. A twelve-year cumulative summary of the all spring and seep surveys <br />including flow measurement results is provided as Table 2. <br />4.3.2 Groundwater Levels <br />Seven piezometers were installed in the area of the Pinnacle Mine to monitor the <br />piezometic surtace 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 />13 <br />