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Pitch Reclamation Project <br />Colorado Mined Land <br />Reclamation Board <br />2008 Annual <br />Reclamation Report <br />inclinometers in P-8 and P-10 remain installed, but are not surveyed on a regular basis. <br />Should surface monuments detect increasing slope movement, data could be collected <br />from these combination piezometers/inclinometers. <br />4.3 Pinnacle Mine Workings Monitoring <br />A concrete plug was constructed in the Pinnacle Adit in September 1995. <br />Authorization for the placement of the Pinnacle Adit plug was requested by Homestake <br />in April 1995, through Technical Revision #4 (TR4) -Pinnacle Adit Closure, Pitch <br />Project, Technics! Revision for Permit #77-4HR (Golder Associates, Inc.). Conditional <br />approval of the Technical Revision request was granted by the Colorado -Division of <br />Minerals and Geology in a letter dated May 26, 1995. <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 continuation <br />of discharge water quality monitoring at the POC (SW-33), monitoring of groundwater <br />resaturation levels, annual spring and seep surveys in areas down-gradient from <br />Pinnacle workings, and monitoring for changes in water quality that could be <br />attributable to resaturation. The stated purpose of the monitoring program is to verify <br />the intended effectiveness of the adit plug. Homestake has continued to monitor the <br />following facets of resaturation through 2008: <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 />In 2009, monitoring the resaturation of the south wall of the North Pit will continue as <br />in 2008. <br /> <br />8 <br />