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February 4, 2009 <br />Pg. 3 <br />• The report refers to mineral acids and occasionally refers to these as solution-based <br />compounds. Is this synonymous with mineral acidity or does it refer to something else? <br />The validity of the data for Deadman Gulch is in question considering that the neutral pH data <br />was measured in the Spring of 2008, when dilution may be considerable, whereas data in Table <br />A-1 shows Deadman Gulch pH in the range of 2.6 to 3.72 in June and Sept 1998-99. Please <br />provide an explanation for the substantial variation in the pH measurements. If the 1.998-99 <br />data cannot be discounted, then please comment on the validity of the conclusions drawn in the <br />first paragraph on pg. 12 regarding potential interactions of Deadman Gulch water with the <br />alluvial material. <br />Pg. 12: The report states that the material encountered in Well B is "native alluvium." Please <br />explain what is meant by "native alluvium." <br />Pg. 12: The report states that the material encountered in Well B has "reducing zone <br />characteristics." To support the statement it is said that the material still contains un-leached <br />mineral character. Please explain in greater detail the minerals that show unleached mineral <br />character. In support of this assertion, were data collected from which to calculate a redox <br />potential, such as dissolved oxygen, Fe(II)/Fe(III) couple, Nitrite/Nitrate, N03/NO2/NH4? <br />Furthermore, Tables A-5 and A-15 indicate that concentrations of pyritic sulfur in the alluvium <br />are below detection limits. It is unusual for shallow alluvium to possess reducing zone <br />characteristics. Please elaborate on the characteristics of the alluvium that warrant the <br />statement that it contains "reducing zone characteristics." <br />Pg. 13: In reference to the statement "... Well B was found to be a reflection of alluvium and <br />rhyolite ground water that has been in contact for `prolonged' periods in order to gain a more <br />acidic and mineralized character", please provide the basis for this conclusion and explain the <br />attributes of water that indicate it has been contact for prolonged periods, especially in light of <br />the fact that the site does not appear to have a monitoring well dedicated exclusively to the <br />rhyolite ground water. <br />Pg. 14: In reference to the statement that "... the mineralization observed in the well cannot <br />physically have been released by the amount of flow + waste rock mineral contribution in that <br />setting", please explain in greater detail the basis for this conclusion. It has been documented <br />in studies of waste rock that oftentimes the bulk of sulfide oxidation occurs in a relatively thin <br />surficial layer available to diffusion of atmospheric oxygen. In light of this, is the waste rock <br />still an implausible source of loading to Well B? <br />Pg. 14: In reference to the statement "Furthermore, analytical results from waste roc]{ solid <br />analysis(+SPLP potential, ABA etc.) were compared to the Well B water chemistry." Please <br />explain the evaluation and conclusions of this. comparison. <br />• Pg. 14: Please define what is meant by "geologic-formation related ground water resources at- <br />depth".