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<br />we believe that most of the carbonate ions will react with the hydrogen ions prior to leaving <br />the mineralized area. <br />CC&V is in agreement with Dr. Posey that the reaction equations are valid only for purposes <br />of investigating causes or control of acid generation. The static and dynamic tests likely give <br />better approximations of some field conditions. However, the degree to which they represent <br />actual and all field conditions is not well known, especially in terms of estimating the effect <br />on drainage of rock matrices surrounding the overburden. <br />Dr. Posey continues "The reactions shown for K-feldspars and sericite dissolution are also <br />equilibrium reactions. The conversion of K-spar to sericite and quartz is a high temperature <br />reaction and cannot be used to depict the Cresson situation. The dissolution of sericite by <br />hydrogen ions and water (reaction [8]) is so slow as to be insignificant. Furthermore, <br />because this is a charge balanced equilibrium reaction, it does not depict the fate of the <br />potassium ion, and its potential effect on metal acidity. In reality, the addition of sulfuric <br />acid to the feldspars and micas in natural open systems, if solution pH is low enough, will <br />release potassium, aluminum and silica to solution. Dissolved Al+', at least, may cause <br />problems for aquatic life." <br />We would ask Dr. Posey, in tum, how he explains supergene alteration of the existing <br />Cresson rock material. The process of supergene alteration is well documented in a variety <br />of geologic publications. The petrographic evidence presented in Appendix 4 of the Volume <br />X submission supports the existence of feldspar and sericite dissolution in the supergene or <br />weathering environment in response to pyrite dissolution. The supergene process that is <br />occurring in the Cresson deposit has been summarized by Dr. Russell Honea who has <br />preformed most of the petrography on the Cresson samples and the summarization is <br />included in Appendix 4 of the Volume X submission. <br />Representation of Deep Core Holes. <br />Aluminum hydroxide will form in a reducing environment (oxygen poor), but AI(OH}r is <br />soluble in either acid or base environments. Aluminum criteria are not included in Cripple <br />Creek water-quality standards. <br />Dr. Posey questions the validity of the assumption that two deep holes are representative of <br />the deeper portions of the diatreme and that there is carbonate present. In this context he <br />states "Section 5.1 states that the 2 deep cores are 'representative' of the entire diatreme at <br />depth. The text states also that the cores contain 3 to 6`% carbonate, even though the <br />carbonate minerals were not identified. These statements are not adequate, as expressed in <br />the DMG's reviews of Amendment 6 submittals. Firstly, there is no rational statistical <br />reason to accept that two cores into the deeper part of the diatreme are representative of the <br />entire mineralized portion of the diatreme..." <br />Dces Dr. Posey have a hypothesis as to why there could be sufficient variation in mineralogy <br />to cause the two drill holes to be unrepresentative? We presume Dr. Posey familiar with the <br />15 <br />