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analysis of the horizontal and vertical ground water flow and ground water gradients in <br />the Diatreme and the adjacent granites for the Cresson Project area, and specifically <br />Grassy Valley is presented in "Cresson Project Hydrogeochemical Evaluation" dated <br />February 2012 and prepared by ABC. <br />The timing and magnitude of the peaks in water level in the monitor wells, piezometers, <br />and boreholes appear to be related to the melting and infiltration of the snow in the spring <br />months and the precipitation events in the summer and fall months. <br />Water quality conditions for monitor wells GVMW -8A, GVMW -8B, GVMW -9A, <br />GVMW -22A, GVMW -22B, GVMW -23B, GVMW -23B, and GVMW -24A in the lower <br />reaches of Grassy Valley are provided in Tables 6 -24 to 6 -29. Time series plots for pH, <br />nitrate, and sulfate are provided in Figure 6 -13. Shallow alluvium ground water is <br />generally characterized as calcium- sulfate water, similar to the surface waters. Shallow <br />and deeper bedrock ground waters (when present) also are characterized as calcium - <br />sulfate waters. <br />The data in Tables 24 to 28 show median field pH values in the shallow bedrock and <br />deeper bedrock to range from 6.0 SU to 7.91 SU. Median nitrate values range from <br /><0.05 mg/L as N to 1.52 mg/L as N. Median sulfate values range from 16.4 mg/L to 83 <br />mg/L. Time series plots are provided in Figure 6 -13. <br />Compiled data and statistics for aluminum, manganese, zinc, which are common <br />geochemical indicators in the Diatreme, also are provided in Tables 6 -24 to 6 -28. The <br />water quality data indicate that aluminum, manganese, and zinc concentrations have been <br />low and or less than detection for the shallow and deep bedrock monitor wells. There are <br />no water quality data for piezometers or boreholes completed in the alluvium in the lower <br />reaches of Grassy Valley. Other trace metals are analyzed as part of the monitoring <br />program. Median values for arsenic, cadmium, chromium, copper, lead, mercury, nickel, <br />selenium, and silver in the ground waters in the shallow and deep bedrock monitor wells <br />were less than or very close to the analytical detection limits. Trace metal data also are <br />provided in Tables 6 -24 to 6 -28. <br />6.4.3.4 MLE2 Impacts to Ground Waters <br />MLE2 will develop WHEX in the upper reaches of Grassy Valley and the ECOSA in the <br />middle reaches of Grassy Valley. WHEX will remove most of the alluvium and bedrock <br />'Cripple Creek & Victor Gold Mining Company <br />Cresson Project Hydrologic Evaluation for Mine Life Extension 2 <br />38 <br />