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Page 10 Water Quality Whirlwind Mine May 5, 2009 Water samples collected at the Whirlwind Mine sump are of the sodium bicarbonate type. The water quality dataset for the sump is generally consistent in concentrations with exception of the June 2008 sample that showed a high pH (10.0) and low bicarbonate and relatively high sulfate. This is likely related to the recent application of shot-crete on the sump roof and walls. PR Spring PR Spring water quality is of the sodium bicarbonate type. An examination of the water quality results and comparison of these data with historic data (Table 2) indicate that the recent (2007 and 2008) data collected by EFR for PR Spring is within the concentration ranges of historical data. The origin and hydraulic connection of PR Spring water will be further evaluated after reconnaissance of the Packrat Mine. This will occur after EFR re-establishes ventilation in the Packrat Mine, possibly in 2010. More discussion of PR Spring water is provided below. Lumsden Creek Surface water associated with Lumsden Creek is of the calcium bicarbonate type. This is consistent with the water type at DP Springs, but different than water quality at PR Spring which is a sodium bicarbonate type. Water quality results for sample sites Lumsden Creek UP and Lumsden Creek DN for data presented in Table 2, did not differ dramatically with exception of the levels of arsenic, uranium, and Ra-226/Ra- 228. Arsenic in the Lumsden Creek UP and Lumsden Creek DN samples showed average concentrations of 0.010 and 0.036 mg/L, respectively. Uranium metal concentrations in the Lumsden Creek UP and Lumsden Creek DN samples showed average concentrations of 0.026 and 0.077 mg/L, respectively. Uranium activity in the Lumsden Creek UP and Lumsden Creek DN samples showed average concentrations of 2.0 and 54.2 pCi/L, respectively. Ra-226 and Ra-228 activity in the Lumsden Creek UP and Lumsden Creek DN samples showed average activity levels of 0.3 and 12.6 pCi/L, respectively. Field parameters, total dissolved solids (TDS), and metals in the Lumsden Creek UP versus the Lumsden Creek DN samples were not appreciably different. Arsenic may show a slight increase at the Lumsden Creek DN site compared to the Lumsden Creek UP site. However, the most obvious impact to water quality (of parameters analyzed) as a result of the Dutchman Mine waste rock are the radionuclide elements of uranium and radium. A comparison of the Lumsden Creek UP and Lumsden Creek DN analytical results to samples collected at similar locations by the BLM in 1993 (Table 2) showed generally as good or better water quality in the June and December 2008 samples than in 1993. TDS concentrations in the June and December 2008 samples were approximately 100 mg/L less than the 1993 samples. Concentration differences may be related to concentration or dilution due hydrologic regime (flow paths, residence time, and the presence or absence of geologic media), and field and laboratory methods used. The Lumsden Canyon Mouth sample was interpreted to have been collected at the same location as past "Lumsden Canyon Spring - Upper Contact" samples. Comparison of the December and June 2008 samples with previous samples at this location show that TDS is elevated from a 1993 average concentration of 562 mg/L to an average 2007/2008 concentration of 670 mg/L. Other than the initial samples from monitoring well MW-W 1, 1993 samples from Lumsden Mine No. 2, and the Dolores River, the Lumsden Canyon Mouth samples have the highest TDS of sample sites in the Whirlwind Weans032709.doc