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Mr. Allen Sorenson, DRMS 3/6/2009 Page 3 of 4 <br />E. Downgradient Well (MW-5) <br />- June 27, 2007, Notes: Awaiting DL Drilling to install well as contracted. <br />- September 26. 2007, Notes: DL Drilling completed well. <br />- November 19, 2007, Notes: Sampled newly completed well with new bailer. Data in <br />Table 4. <br />- March 11, 2008, Notes: Data in Table 4. <br />- June 18, 2008, Notes: Data in Table 4. <br />- September 15, 2008, Notes: Data in Table 4. <br />- December 17, 2008, Notes: Sample taken, data pending. <br />Five quarters of water monitoring data are not yet available. A proposed temporary <br />baseline for the Downgradient Well (MW-5) is presented in Table 4 <br />Table 4 Downgradient Well - parameters <br />2. Summary of Results <br />Sampling results for all proposed locations are displayed above in Tables 1 through 4. All <br />Tables also include appropriate baselines for each location as well as Colorado agricultural <br />groundwater standards and calculated 99% upper confidence limit for each analyte. <br />Cash Gulch (SW-1) is an ephemeral streambed. Minimal sampling events due to the <br />ephemeral nature of the stream flow have been completed. Dissolved cadmium, copper <br />and zinc exceed Colorado Agricultural Standards. The measured pH mean is lower than <br />those standards. This is likely attributable to the historic mine dumps in the area, <br />significant organic content (pine duff, etc.), and the stagnant nature of the water. MRV <br />suggests that a baseline be established following five (5) quarters of available data for all <br />analytes per TR05 of the permit, that the sampling suite be reduced to the analytes for <br />which five (5) quarters of data is available, or that this sampling point be eliminated from <br />the monitoring plan. <br />• Unnamed Gulch (SW-2) is also an ephemeral streambed. To date, no sampling has been <br />performed as no water was present during quarterly sampling. MRV suggests that a <br />baseline be established following five (5) quarters of available data per TR05 of the <br />permit, or that this sampling point be eliminated from the monitoring plan. <br />Upgradient Well (MW-1) was completed on or about September 27, 2007. No <br />significant change in the water quality has been observed as a result of the completion of <br />this well. Colorado Agricultural Standards are applicable to this well and are proposed to <br />be the permanent baseline for water monitoring at this location. MRV requests that <br />sulfate (as SO4) be eliminated from the required reporting for this location. <br />Cash Mine Pool (CW) water appears to have seasonal variation to water quality. Clearly, <br />and as expected, this represents the most impaired water of the sampled set. The Cash <br />Mine, as a historic mine, with significant depth, stagnant waters, and greater exposed <br />surface area of contact between water, mineralized rock and the atmosphere, is of lower <br />pH and higher metal content than agricultural standards. The proposed baseline, based <br />on the most recent five (5) quarters of data available has a higher dissolved cadmium, <br />2007-8 Mine Water.doc