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EPP Adequacy Review No. 2 3 19 March 2010 <br />Schwartzwalder Mine File No. M-1977-300 <br />SECTION 8. GROUNDWATER INFORMATION <br />3) Operator states on pg 8-7 "Two bedrock wells are proposed for drilling in 2010, MW 13 and <br />MW 14." Please indicate the proposed locations of these wells on a map, and please provide <br />proposed total depths and locations/depths of screened intervals. <br />4) Operator states on pg 8-37 "Ralston Creek does not appear to be in strong hydraulic connection <br />with the Schwartzwalder Mine based on stream flow rates, mine pumping rates, and isotopic <br />comparison of mine water and surface water." <br />DRMS does not agree with this statement. Considering the elevated concentrations of uranium <br />and molybdenum in the mine pool, adverse impacts to Ralston Creek could result from relatively <br />small inflow rates that might not be discernible in the streamflow or isotopic data. Please <br />provide an evaluation of possible seepage from the mine pool to the alluvium. <br />5) Operator states on pg 8-41 "These results indicate that mine pool is not contributing loading to <br />Ralston Creek at this location." This issue requires further analysis to more thoroughly assess <br />any connection between the mine pool, the regional ground water gradient and possible hydraulic <br />communication along the Schwartz trend. A lack of geochemical evidence for a connection at <br />present should not be taken as irrefutable evidence that a connection does not or will not exist in <br />the future under conditions of hydraulic equilibrium. <br />SECTION 9. GROUNDWATER QUALITY <br />6) Operator states on page 9-49: "Water seeping into the upper levels of the mine is impacted by <br />acid rock drainage..." This statement conflicts with the statement on pg 6-1 "No acid-forming <br />materials exist on site." <br />The locations, compositions, quantities, and potential impacts of the acid-generating materials of <br />the mine area do not appear to be well characterized. The water seeping into the upper levels of <br />the mine is described as having pH as low as 2.7, uranium up to 150 mg/L, copper up to 19 <br />mg/L, and total dissolved solids as high as 11,000 mg/L (pg. 9-49). This is not something that <br />can be easily dismissed. Please provide a more complete characterization of the acid-generating <br />materials, including the possible scenario that, with the workings in a flooded condition, the <br />acid-generating materials are exposed in an unsaturated condition and perhaps preferentially <br />weathered and may be contributing a larger share of loading to the mine pool than in an un- <br />flooded condition. <br />7) Ground water and surface water monitoring: Phosphorus can exert an important influence on <br />uranium speciation and mobility in natural waters. Although P is not a regulated parameter, the <br />operator must include total P or P04 in all future ground water and surface water samples. <br />8) The statement on pg 9-3 that the drinking water standards are not considered to be directly <br />applicable to the alluvial monitoring wells or to groundwater in the underground void because <br />these are not direct sources of drinking water supply is not appropriate. The mine pool and local