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Pitch Reclamation Project Colorado Mined Land Reclamation Board — 2012 Annual Reclamation Report (TR4) — Pinnacle adit Closure, Pitch Project, Technical Revision for Permit #77 -4HR (Golder Associates, Inc.). Conditional approval of the Technical Revision request was granted by the Colorado Division of Minerals and Geology, in a letter dated May 26, 1995. The intention of the plug was to partially seal the Pinnacle adit and allow the historical underground working and adjacent area to resaturate. The resaturation of the workings was expected to re- establish a geochemically reducing environment and lower the solubility of uranium and radium within the underground workings of the Pinnacle Mine. The Division's approval of TR -4 required Homestake to monitor the effects of resaturation in the Pinnacle workings for five years or until hydrologic conditions stabilized. Components in the Monitoring Plan outlined in TR4 (Section 4.0), included continuation of discharge water quality monitoring at the POC (SW -33), monitoring of groundwater resaturation levels, annual spring and seep surveys in areas down - gradient from Pinnacle workings, and monitoring for changes in water quality that could be attributable to resaturation. The stated purpose of the monitoring program is to verify the intended effectiveness of the adit plug. Homestake has continued to monitor the following facets of resaturation through 2012: • Survey of springs and seeps; • Groundwater levels in piezometers installed in the area of the Pinnacle workings; • Water quality and flow from the Pinnacle adit at sampling point PP -01; and • Monitor discharges from the property at the CDPS permit POC SW -33. As in 2012, monitoring the resaturation of the south wall of the North Pit will continue in 2013. 4.3.1 Spring and Seep Monitoring Spring and seep surveys were conducted to monitor changes in shallow groundwater conditions due to construction of the Pinnacle Adit plug. These surveys have been conducted annually since July 1995 and were repeated in 2012. In general, flow from some springs and seeps increased for a brief period after the adit plug installation and have declined to a steady state since the spring of 1997. Small variances noted since 1997, are believed to be attributable to a variety of conditions including precipitation, depth of snow pack, timing of snowmelt, and the potential for infiltration with respect to frozen ground. All "active" spring and seep locations are shown in Figure 3. Springs and seeps currently designated as "inactive" (no flow or seepage observed over the past five years) are not shown, but can be found on maps issued with past reports. A new spring (IC -12) was found and monitored in 2008. Its flow rate was consistent with the other springs. Table 1 shows spring and seep data, including flow measurements, from 1995 to the present. Spring IC -4 has experienced an increased flow over the past couple of years due to higher snow packs at the site since 2005. The flow in IC -4 and all springs decrease rapidly during the early summer months to a point where there is little to no flow in the fall. Monitoring of springs and seeps will continue in 2013. 4.3.2 Groundwater Levels Seven piezometers were installed in the area of the Pinnacle underground mine workings to monitor the piezometric surface within the area behind the adit plug. The piezometers are identified as P4 through P10. Piezometer P7 was installed as a replacement for P6, which was lost during plug grouting /construction. The locations of these piezometers are provided in Figure 3. All six piezometers fluctuate seasonally with the highest levels in late May or early June sympathetic with snowmelt. A hydrograph of the piezometer water levels is provided as Figure 4. Piezometers located within the Pinnacle workings include P -4 and P -5. P -9 is located downgradient of the Pinnacle workings and also Pitch 2012 Reclamation Report 04 -16 -13 Doc 18