Laserfiche WebLink
• <br />Minutes, April 22-Z3, 1992 <br />resolve the problems a <br />monitoring, a focus on <br />make appropriate permit <br />faith efforts were taken <br />DF~FT z8 <br />Subject To Board Approval <br />t the site, including investigations, expanded <br />environmental protection and a commitment to <br />modifications. He said the operator feels good <br />to resolve the problems at the site. <br />Mr. Andre Duchane provided a detailed discussion of the the occurrence <br />of problems at the site and provided some clarifications, regarding the <br />operator's responses. He discussed the ore bodies, approximately 12 <br />million tons, from the east and west pits. Mr. Duchane discussed the <br />dual lined tailings system, stating that this includes high density <br />polyurethane. He stated that the magnitude of the problem was <br />realized, after ice thawed ai: the site. Mr. Duchane said consultants <br />contacted in March of 1992 suggested that the CyTox chemical would be <br />effective in reducing the cyanide concentrations to acceptable levels. <br />He discussed the operator's experiments with different cyanide <br />detoxification tests. <br />Mr. Duchane assured the Beard that if the Division or operator <br />perceives further problems at the site, the plant will be closed. He <br />answered questions from the Board. <br />Mr. Carl Ellers addressed the Board briefly and assured the Board of <br />the operator's commitment to work with the Division and the community <br />of San Luis to resolve problems and assure a safe operation at the site. <br />In response to an inquiry from Mr. Johnson, Mr. Massey clarified that <br />the operator was in agreement with all of the items listed by the <br />Division as requirements for abatement. <br />At this time, the Board heard presentations provided by the objectors. <br />Ms. Helen Sigmund, an attorney representing the Costilla Conservancy <br />District, stated that they wanted to address points made during <br />presentations by the Division and the operator. Ms. Sigmund presented <br />EXHIBIT C, the resume of Dr. David Hyatt, an expert chemist, and <br />lysimeter reports in relation to water samples taken from the site. <br />Dr. Hyatt said he had an opportunity to review tapes from earlier <br />hearings, during which he presented technical information. He <br />discussed the fact that no documentation presented or that he had <br />reviewed showed levels of cyanide at the permitted levels. Therefore, <br />Dr. Hyatt suggested that the mine has possibly never operated within <br />compliance levels. <br />Dr. Hyatt stated that the elevations of cyanide levels in the tailings <br />dre dangerous and that implications from the non-operating treatment <br />system are that cyanide is probably going out into the tailings dam. <br />In discussing the operator's use of CyTox to detoxify the cyanide, Dr. <br />Hyatt stated that it is not known, from the limited amount of testing, <br />whether the chemical will eliminate the high levels of cyanide in the <br />water. However, he said that the although this may reduce the levels <br />of cyanide in the water, the cyanide will be transformed into iron <br />cyanide solids and will settle, in high concentrations, in the tailings <br />