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Pitch Reclamation Project <br />Colorado Mined Land <br />Reclamation Board <br />2008 Annual <br />Reclamation Report <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 2008. 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 snowmelt, and the potential for infiltration with respect to <br />frozen ground. All "active" spring and seep locations are presented in Figure 3. <br />Springs and seeps currently designated as "inactive" (no flow or seepage observed <br />over the past five years) are not shown, but can be found on maps issued with past <br />reports. Anew spring (IC-12) was found and monitored in 2008. Its flow rate was <br />consistent with the other springs. Table 2 shows spring and seep data, including flow <br />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 />piezometic 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 2008, in spite of the increase snowpack and rainfall, the phreatic <br />surfaces in all piezometers showed a comparatively normal spring cycle. The water <br />level data indicates a relatively constant levels or gradual upward trends that have <br />been observed since 2000. A hydrograph of the piezometer water levels is provided <br />as Figure 4. <br />4.3.3 Pinnacle Adit Flow <br />The flow rate from the Pinnacle Adit at PP-01 has been monitored since November <br />1993. The flow from the adit remains in a seasonal pattern of high flows during the <br />short period of spring melt in late May or early June and stable flows of less than 10 <br />gallons per minute (gpm) throughout the year. The measured peak flow for the 2008 <br />season was 40.7 gpm on June 10, 2008. A hydrograph of the Pinnacle Adit flow at <br />PP-01 is provided as Figure 5. The spike in flows observed at PP-01 each spring are <br /> <br />9 <br />