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~! <br />The following pages describe these points in more detail. <br />1. Problem: <br />"Representative" analyses of waste rock from the Cresson pit <br />indicate a potential for Qeneration of acid and dissolved <br />metals (Acid Rock Drainage - ARD) in excess of table value <br />standards. Whether this generated acid and metal will be able <br />to meet surface and groundwater standards is not known. <br />Previously, the company has provided "letter reports" <br />concluding there is no potential for ARD generation. These <br />letter reports have been deemed inadequate for the following <br />reasons. <br />1. The letter reports disagree with all of the <br />consultants reports. <br />2. The letter reports disagree with DMG evaluations. <br />3. The letter reports were not prepared by persons <br />qualified in the subject matter, as required by the <br />regulations. <br />Solution: <br />CC&V must quantify the probable amounts of ARD that will be <br />released to surface and groundwater. <br />If it cannot be demonstrated that the ARD will meet surface <br />water quality standards, and ground water quality conditions <br />set by the Division, then the operator should revise their <br />environmental protection plan to meet the standards and <br />conditions. <br />Notes: <br />In previous assessments, we compared dissolved metals and pH <br />results with Table Value Standards. This method was employed <br />because TVSs were either in place at the time of the <br />evaluation or because we assumed that Temporary Modifications <br />will remain in place, at most, for the life of the mine only; <br />afterwards, the temporary mods should revert to TVS. <br />Groundwater compliance values, set by DMG, will^ n place for <br />good. <br />Given this situation, I see no need to compare leach test <br />results to the current temporary modifications because the /~ <br />temporary mods, by definition, must expire. Unless }cou~ec3-de ~/ <br />otherwise, =l-wi-11- not revise the previous assessments. <br />However, depending on the outcome of the CC&V/CDPHE <br />litigation, we may have to re-evaluate the surface water <br />quality standards against which we base our assessment. Even <br />so, this will not change the values against which we will <br />judge the groundwater standards. And please note: I assume <br />2 <br />