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<br />Arequa Gulch and slightly higher. That is to be expected for iron throughout the volcanic <br />caldera. <br />CC&V has added graphs for lead, mercury, nickel, selenium, and silver as attachments to <br />this response. Most of these may be characterized as showing AccuLabs data within the <br />general range of, or below AG-1 concentrations and the ICP detection limit above the <br />detection limits used to measure most AG-1 samples. AccuLabs data for lead show <br />AccuLabs less-than values in the range of AG-1. AccuLabs data for mercury, also less-than <br />values, is in the lower part of the AG-1 range. Nickel data for the humidity cells is well <br />below the range in nickel concentrations in Arequa Gulch (AG-1). Selenium concentrations <br />in the humidity cell extracts aze, on occasion, above the maximum (<0.01) reported for AG- <br />1. Silver concentrations for humidity cell extracts measured by AccuLabs aze less than <br />values below the average for AG-1. <br />Manganese concentrations in the humidity cell extracts aze lower than Arequa Gulch as aze <br />zinc concentrations in the extracts. <br />OMLR's Conclusions. <br />Dr. Posey concludes "If CC&V [is] allowed to proceed with their proposed waste and spent <br />ore disposal plans, albeit not yet approved by the DMG, it is likely that water discharging <br />from the site will not meet water quality standards. Also, it is likely that water which filters <br />into the spent ore and waste rocks will dissolve metals and generate acid that, once <br />dischazged to groundwater, will not meet ambient groundwater quality criteria." <br />"It is incumbent upon CC&V to prepaze for the Division a reclamation plan to prevent the <br />generation and release of acid and toxic materials. Capping of the heap and waste rock pile <br />would be acceptable provided the caps are sufficiently impermeable to slow the generation <br />and release of acid and toxic materials to meet water quality compliance criteria. The simple <br />monitoring plan, as proposed in the document under review, is not an acceptable solution to <br />the likely generation of acid and toxic substances." <br />CC&V's Conclusions. <br />It remains CC&V's position that the water quality measured from extracts derived from the <br />humidity-tell-tested cores is quite similaz to the measured water quality in Arequa Gulch. <br />Therefore CC&V sees no reason to provide any proposals for reclamation that are in addition <br />to the revegetation requirements that already exist. These requirements include replacement <br />of soils. We have provided comparisons between the quality of the extracts drawn from the <br />humidity cells and the results of analyses of Arequa Gulch. We have demonstrated that <br />water quality of the two sources differ very little. It is CC&V's belief that drainage from the <br />overburden destined for Arequa Gulch will not be distinguishable from baseline drainage <br />quality. <br />Dr. Posey's comparisons of humidity cell effluent should focus on ambient water quality <br />first, and then on Table Value Standazds where these aze higher (in concentration) than <br />22 <br />