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Compiled data and statistics for aluminum, manganese, zinc, which are common <br />geochemical indicators in the Diatreme, also are provided in Tables 6 -5 to 6 -12. The <br />water quality data indicate that aluminum, manganese, and zinc concentrations have been <br />low and or less than detection for the alluvium and shallow and deep bedrock monitor <br />wells. Other trace metals are analyzed as part of the monitoring program. Median values <br />for arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, and silver in <br />the ground waters in the alluvium and shallow and deep bedrock monitor wells were less <br />than or very close to the analytical detection limits. Trace metal data also are provided in <br />Tables 6 -5 to 6 -12. <br />6.4.3.2 Middle Grassy Valley <br />Table 6 -4 and Figure 2 -2 provide the details and location of the monitor wells and <br />boreholes in the middle reaches of Grassy Valley. Ground water levels in alluvium <br />(boreholes) are generally shallow at 9.83 to 51.5 feet below measuring point bmp. <br />Ground water levels in shallow bedrock monitor wells vary from 5.21 to 194.33 feet <br />bmp. Ground water levels in deeper bedrock monitor wells vary from 102 feet bmp to <br />dry ( >750 feet bmp). CAM -1C, CAM -1D, WL -1C, WL -1D, GW -20, and several <br />OSABH locations have been dry or have very limited sample data since installation. <br />Figures 6 -7 and 6 -8 show the pressure transducer calculated depths to water in the middle <br />reaches of Grassy Valley. A comprehensive analysis of the horizontal and vertical <br />ground water flow and ground water gradients in the Diatreme and the adjacent granites <br />for the Cresson Project area, and specifically Grassy Valley is presented in "Cresson <br />Project Hydrogeochemical Evaluation" dated February 2012 and prepared by ABC. <br />As with the upper reaches of Grassy Valley, the timing and magnitude of the peaks in <br />water level in the monitor wells, piezometers, and boreholes in the middle reaches appear <br />to be related to the melting and infiltration of the snow in the spring months and the <br />precipitation events in the summer and fall months. <br />Water quality conditions for monitor wells GVMW -4A, GVMW -4B, GVMW -6A, <br />GVMW -7A, GVMW -7B, GVMW -10, CAM -1A, CAM1B, COB -1A, COB -1B, and WL- <br />1A in the middle reaches of Grassy Valley are provided in Tables 6 -13 to 6 -22. Water <br />quality conditions for the boreholes OSABH -1, OSABH -2, OSABH -4, and OSABH -6 in <br />the upper reaches of Grassy Valley are provided in Table 6 -23. Time series plots for pH, <br />nitrate, and sulfate are provided in Figures 6 -9 to 6 -11. Shallow alluvium ground water is <br />generally characterized as calcium - sulfate water, similar to the surface waters. Shallow <br />'Cripple Creek & Victor Gold Mining Company <br />Cresson Project Hydrologic Evaluation for Mine Life Extension 2 <br />36 <br />