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10 <br />ryanide spike recoveries performed on samples with detectable cyanide concentrations that <br />may have analytical interferants. Therefore, the only important QAJQC analysis that used <br />Battle Mountain samples was the total ryanide spike analysis on the unfiltered upper tailings <br />pond sample. The result for this spike recovery analysis was 87%, which is within the <br />acceptable guidelines for spike recoveries for cyanide (75-125%). The unfiltered upper <br />tailings pond total ryanide concentration reported in the Analytical Report is 680 µg/1, while <br />the original value reported in the Quality Control Report is only 220 µg/1 (page 26). <br />According to Core Laboratories (personal communication, Lyn Benkers, 7/15/93)), this is <br />because the sample was diluted 1:3, and the actual analyzed concentration (not corrected <br />for dilution) was reported. The spike added was 80 µg/1 and the analyzed value was 290 <br />µg/l. The original value is 220 µg/l, and the %R is 87%. Given the problems with WAD <br />and total cyanide and the noted differences in ryanide concentrations ih filtered and <br />unfiltered samples, it would be important to conduct spike recoveries on every process point <br />sample, especially unfiltered samples. <br />3.4 LABORATORY TURNAROUND TII14E <br />The laboratory turnaround time was somewhat improved for this sampling. Core <br />Laboratories received the samples on April 29, 1993. The date of the Analytical Report <br />from Core Laboratories was May 27, 1993, which is a turnaround time of slightly under one <br />month. <br />4.0 CONCLUSIONS AND RECOMMENDATIONS FOR FUTURE <br />SAMPLING <br />- Groundwater well samples were collected on this monitoring trip, and all <br />cyanide concentrations were below detection. <br />- WAD ryanide concentrations were higher than total concentrations in both <br />unfiltered and filtered lower tailings pond samples. Total ryanide <br />concentrations were higher in filtered than unfiltered samples for both the <br />upper tailings pond and the lower tailings pond samples. WAD cyanide <br />concentrations were also higher in 5ltered than in unfiltered samples at these <br />same locations. These results indicate that fairly significant analytical <br />problems still etdst with cyanide determinations in samples front the site. <br />- Given the problems with WAD and total ryanide and the noted differences <br />in. ryanide concentrations in 5tered and unfiltered samples, it would be <br />important to conduct spike recoveries on every process point sample, <br />especially unfiltered samples. <br />RCG/Flagler, Bailly, Inc <br />