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III IIIIIIIIINIIIII <br />999 <br />RCGjHagler, Bailly, Inc. <br />PO Drawer O <br />Boultler, Colorado 80306-1906 <br />303/449-5515 • Fax 3031443-5684 <br />January 21, 1994 <br />Harry H. Posey, Ph.D. <br />Reclamation Specialist <br />Division of Minerals and Geology <br />Colorado Department of Natural Resources <br />1313 Sherman St., Rm. 215 <br />Denver, CO 80203-2273 <br />Dear Dr. Posey: <br />~;~ <br />,,. ./qN ~41~94 <br />., <br />I have addressed the issues identified in your December 31, 1993 letter regarding the <br />Draft Summary Report for the October 1993 third-party monitoring trip and changed the <br />Summary Report accordingly. Please find enclosed the amended Summary Report for <br />the October 1993 trip. <br />The first two issues in your letter addressed violation of laboratory QA/QC criteria. As <br />you state, the acceptance criteria for duplicate analyses were not met for total cyanide <br />analysis of both upper and lower tailings impoundment samples. In addition, reanalysis <br />of these samples took place after the recommended 14-day holding time. These <br />conditions led to identification of total cyanide values far the upper and lower tailings <br />impoundment samples as "estimated" values. As I now state in the report, exceedence <br />of the holding time results in values that, if anything, are lower than the actulal values in <br />the sample. However, the measured total cyanide values are well above detection limits <br />and fall within previously measured values for the upper and lower tailings impoundment <br />samples, and I do not feel, therefore, that the data are "rejected" or that resaunpling and <br />reanalysis will be necessary. <br />In the case of total cyanide analysis of the groundwater sample from well M-9, the <br />analyzed value is below detection. Because cyanide analyses conducted past the holding <br />time may be lower than actual sample concentrations, this total cyanide measurement is <br />rejected. However, because there has never been a cyanide "hit" in well M-9, resampling <br />is not recommended. I do recommend, however, that the Division check the past three <br />months of sampling results from well M-9 to confirm that no recent cyanide hits have <br />occurred. Table 3 has been amended to include a footnote about the exceedence of <br />holding time for total cyanide determination for sample M-9. <br />1 <br />Management Economic. antl Technical Counsel • Principal Offices Throughout the Worlo <br />