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monitor wells, two are in the diatreme and the remainder are in the granite bedrock. The <br />wells range in depth from 30 to 200 feet bgs. Ground water levels in shallow bedrock <br />monitor wells vary from 6.88 to 53.95 feet below measuring point. Deeper bedrock <br />ground water monitoring wells (defined as greater than 200 feet) include ten in Upper <br />Grassy Valley, of which one is in the diatreme and the remainder are in the granite <br />bedrock. Ground water levels in the deeper bedrock monitor well vary from 185.88 to <br />218.65 feet below measuring point to dry ( >800 feet below measuring point). The timing <br />and magnitude of the peaks in water level in the monitor wells, piezometers, and <br />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. Note that many of <br />the shallow and deeper bedrock wells are dry in Upper Grassy Valley, likely due to the <br />drainage of bedrock water into the diatreme. <br />Shallow alluvium ground water in Upper Grassy Valley is generally characterized as a <br />sodium- sulfate water. Shallow and deeper bedrock ground waters (when present) are <br />characterized as sodium - bicarbonate to calcium - sulfate waters. Median field pH values <br />for the shallow bedrock and deeper bedrock range from 5.74 to 6.72. Median nitrate <br />values range from 0.60 mg/L -N to 10.7 mg/L -N. Median sulfate values range from <10 <br />mg/L to 118.5 mg/L. Median field pH values for the alluvium range from 6.05 to 6.21. <br />Median nitrate values to range from 0.08 mg/L -N to 2.2 mg/L -N. Median sulfate values <br />to range from 31.6 mg/L to 78.5 mg/L. <br />There are 14 boreholes screened in shallow, alluvial /colluvial materials in Middle Grassy <br />Valley. These monitoring sites range in depth from 23 to 52 feet bgs. Ground water <br />levels in alluvial boreholes are generally shallow at 9.83 to 51.5 feet below measuring <br />point. There are six monitor wells screened in shallow bedrock (defined as less than 200 <br />feet in depth) in the Middle Grassy Valley of which three are in the diatreme and the <br />remainder are in the granite bedrock. The wells range in depth from 50 to 185 feet bgs. <br />Ground water levels in shallow bedrock monitor wells vary from 5.21 to 194.33 feet <br />below measuring point. There are 13 deeper bedrock ground water monitoring wells <br />(defined as greater than 200 feet) in Middle Grassy Valley of which six are in the <br />diatreme and the remainder are in the granite bedrock. Ground water levels in the deeper <br />bedrock monitor well vary from 102 to dry at >750 feet below measuring point. As with <br />Upper Grassy Valley, the timing and magnitude of the peaks in water level in the monitor <br />wells, piezometers, and boreholes appear to be related to the melting and infiltration of <br />the snow in the spring months and the precipitation events in the summer and fall months. <br />Cripple Creek & Victor Gold Mining Company <br />Cresson Project Mine Life Extension 2 <br />4 -17 <br />