2012-02-28_REVISION - M1980244 (95)

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(Figure 5 -4) show 0 -4 water level peaks per year. The high and low water levels in SG- 04PZ from 2007 -2011 (hand measurement only) broadly correspond to the highs and lows of SGMW -3B for both pressure transducer and hand measurements. The timing and magnitude of the peaks for the shallow monitor well and the piezometer are related to the melting and infiltration of the snow in the spring months and the precipitation events in the summer and fall months. The variably saturated conditions in the shallow monitor well (SGMW -3B) and the dry conditions in the co- located deeper monitor well (SGMW- 3A) suggest a downward gradient and that the shallow bedrock ground water is captured by the Diatreme at this location. The dry conditions in SGMW -5 also indicate that the granites adjacent to the Diatreme are drained. A comprehensive analysis of the horizontal and vertical ground water flow and ground water gradients in the Diatreme and the adjacent granites for the Cresson Project area, and specifically Grassy Valley is presented in "Cresson Project Hydrogeochemical Evaluation" dated February 2012 and prepared by ABC. Water quality conditions for SGMW -3B and SG -04PZ are provided in Tables 5 -6 and 5- 8. Shallow alluvium (SG -04PZ) and shallow bedrock (SGMW -3B) ground waters in Squaw Gulch are characterized as calcium- sulfate water, similar to the surface waters. Data in Tables 5 -6 and 5 -8 show a median pH value of 4.81 SU in the alluvium (SG- 04PZ) and a median pH value of 5.88 SU in the shallow bedrock (SGMW -3B). Median nitrate values are 4.31 mg/L as N in the alluvium and 0.51 mg/L as N in the shallow bedrock. Median sulfate values are 423 mg/L in the alluvium and 595 mg/L in the shallow bedrock. Time series plots of the pH, nitrate, and sulfate data are provided in Figure 5 -5. Compiled data and statistics for aluminum, manganese, and zinc, which are common geochemical indicators in the Diatreme, are provided in Tables 5 -6 and 5 -8. The water quality data indicate relatively stable concentrations for aluminum, manganese, and zinc at SGMW -3B and SG -04PZ since 2001 and 2007, respectively. Deeper ground water quality data in the Diatreme (SGMW -3A) and the granite (SGMW -05) are absent due to the dry conditions created by the Diatreme drainage. Other trace metals are analyzed as part of the monitoring program. Median values for arsenic, chromium, lead, mercury, selenium, and silver in the ground waters at SGMW -3B and SG -04PZ were less than the analytical detection limits. Median concentrations of cadmium, copper, and nickel at SG- 5 SGMW -3B showed elevated manganese values in 1998 -2000. These values decreased in 2001 and have remained relatively stable through 2011. 'Cripple Creek & Victor Gold Mining Company Cresson Project Hydrologic Evaluation for Mine Life Extension 2 19