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1 <br /> <br /> Pitch Reclamation Project <br /> Colorado Mined Land <br />' Reclamation Board <br /> 2007 Annual <br /> Reclamation Report <br /> <br />verify the intended effectiveness of the adit plug. Homestake has continued to monitor <br />' the following facets of resaturation through 2007: <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 thl~e property at the Point-of-Compliance SW-33. <br /> In 2008, Homestake will continue tlo monitor the resaturation of the south wall of the <br /> North Pit as done in 2007. <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 2007. 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 snow~melt, and the potential for infiltration with respect to <br /> frozen ground. All "active" spring and seep locations are presented in Figure 3. <br /> Locations of springs and seeps currently designated as "inactive" (no flow or seepage <br /> observed over the past five years)~i,have been removed from Figure 3. Locations of <br /> inactive springs and seeps can be found on maps issued with past reports. A thirteen- <br /> year cumulative summary of th~,e all spring and seep surveys including flow <br /> measurement results is provided as Table 2. <br />' 4.3.2 Groundwater Levels I~ <br />' Seven piezometers were installed I~~ 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 the <br />highest levels in late May or early June. The water levels are sympathetic with <br />' snowmelt and large precipitation events and decrease to stable levels after these <br />events. During 2007, the phreatic surfaces in all piezometers showed a comparatively <br /> <br />14 <br />