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<br />different than that of waste rock from underground mining and that underground-mined rock <br />has, for the most part, higher sulfur concentrations than the Cresson rock. It is not at all <br />clear that wet-dry cycles will significantly change between in situ bedrock and overburden <br />piles. It is not at all clear that bacterial effects will vary or that freeze-thaw cycles will <br />affect the overburden any more than they do the bedrock. Further, bacteria may play a role <br />only under low pH conditions that generally do not exist in the District. CC&V has yet to <br />see data that indicate the Cresson overburden will act differently than the undisturbed rocks <br />because of these factors. <br />Dr. Hyatt confirms the following conclusion: "In some cases, waters which had contacted <br />the Cresson materials were of comparable quality with respect to acidity and trace metals to <br />the naturally occurring water from Arequa Gulch. In other cases, particularly the waters <br />contacting higher sulfide materials, the efFluents were more acidic (had lower pH levels) <br />and/or contained higher levels of trace elements (most typically zinc) than the Arequa Gulch <br />water." This, of course, is the basis of CC&V's planned operations where the higher sulfide <br />materials are handled separately and additional management practices are to be employed in <br />the single geographical area in which the potential for transport of water is present. <br />Equally important is Dr. Hyatts' conclusion that "Data presented on the laboratory simulated <br />release of acid and metals taken from sites in the vicinity of the Cresson project suggest that <br />they behave much like some of the (higher sulfur) Cresson materials. Earlier reports on the <br />Cresson project have suggested that there is no significant evidence of highly acidic <br />discharges from existing waste materials in proximity to the project (such as these waste <br />rocks) even though these materials have been exposed to ambient oxidation and leaching for <br />relatively long times." This conclusion is exactly correct in that the majority of the so-called <br />"waste rock" (or low grade ore) from the underground mining operations is ore with higher <br />sulfide concentrations -and yet there is no measurable impact on the surface waters of the <br />District as a result of these waste rock piles. <br />Dr. Hyatt does note that, in his opinion, the discussion of water-quality monitoring is <br />limited. CC&V agrees that such discussion in the material reviewed by Dr. Hyatt is limited. <br />In part that is because most all elements of our water quality monitoring program are <br />described elsewhere in materials provided [he OMLR. In particular Dr. Hyatt notes that <br />"there is little discussion of the need or plans for monitoring waters from the disposal areas <br />where highest sulfur materials are stored." He hypothesizes that "In case of the Ironclad and <br />Globe Hill pits, drainage or seepage would appear to enter Squaw Gulch." He specifically <br />suggests that monitoring of water draining from the Ironclad and Globe Hill Mines into <br />Squaw Gulch might well be monitored. <br />The OMLR is aware that no Flows have been detected at the base of the Ironclad -Globe Hill <br />overburden storage area since large-scale mining has been conducted in the area. Further, <br />water seldom accumulates in either the Globe Hill or Ironclad mines, which are relatively <br />small in comparison to many other mines. Nonetheless CC&V has two monitoring wells <br />located in Squaw Gulch which the OMLR has inspected. Dr. Hyatt did not have this <br />3 <br />