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<br /> <br />that the mineralogy of these zones is not unique or homogeneous. Pyrite is found in the oxide zone <br />and, if exposed to weathering, will produce acid. The degree to which it will produce acid depends <br />on the degree of crushing (amount of surface exposure) and the amount of pyrite in discrete segments <br />of the rock mass. Because some parts of the so-called oxide zone have higher pyrite concentrations <br />than others, the degree to which those parts can produce acid and metals depends on their mineralogy, <br />not on CC&V's classification. <br />Also in this section, the operator persists in presenting conclusions about the degree of <br />carbonate available in the rock for neutralizing acid despite the absense of evidence showing that <br />carbonate is actually available. Actual identification of carbonate minerals has been rare. Also, the <br />humidity cell tests indicate that whether carbonate is present or not, it is not doing the job of <br />neutralizing the acid. <br />Section 6.2 refers in part to the strong positive corelation between total sulfur and visual <br />sulfides. In fact, visual estimates of drill core made in the drill core lab are generally higher than <br />sulfide sulfur content. However, the Division is concerned about how pyrite content will be monitored <br />in the ore and waste rock during open pit mining operations. The Division will require a detailed plan <br />to be approved by the Division which explains; (1) how the pyrite content will be accurately <br />determined and at what frequency, and (2) how specific volumes of material will be handled to protect <br />surface and groundwater quality during mining operations. <br />Section 7.2 states that samples containing less 0.62 ~ pyrite will not cause an acid problem <br />because they are encapsulated by silicates. This is not borne out by the humidity cell tests. <br />Section 7.4 states that meteoric rinse test results show that zinc was the only trace metal <br />detected in significant amounts in the samples, with the highest level being 0.54 mg/L Zn. This is <br />incorrect. The highest zinc value was actually 16 mg/L, nearly 3~times higher. In addition, elevated <br />levels of F, Sr and, in one sample, Se, were detected in the leacl~ate. Minor amounts of As, Cu, Mo ~~ p~ <br />and Ni were also detected. <br />Section 8.3, on page 30, states that although the thin section analyses did not detect "liberated" <br />pyrite, drainage pH values and relatively high sulfate and net acidity values indicate that reactive pyrite <br />is present and is oxidizing. From this conclusion, the inferences made comparing "liberated" pyrite <br />in thin sections and acid-generating potential elsewhere in the report is erroneous. <br />APPENDIX 1 <br />There appears to be a Quality Assurutce/Quality Control in the sample results presented. One <br />of the samples was mis-identified, either in the lab or in the field. <br />My copy of the report contains only a single page (page 6) of the McClelland lab report dated <br />July 17, 1993. I am not sure how to interpret this. <br />APPENDIX 8 <br />None of the original reporting sheets from the labs are presented. <br />APPENDIX 9 <br />None of the original reporting sheets from the labs are presented. <br />Detection levels are not low enough for some metals. <br />Despite the above two criticisms, it is evident that some of the leachates exceed water quality <br />standards. Therefore, it is evident that the rocks from which these materials were derived will need <br />