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to <br />ryanide spike recoveries performed on samples with det.ctable cyanide concentrations that <br />may have analytical interferants. Therefore, the oily intporGant QA/QC anal}~sis that used <br />Battle Mountain samples was the total ryat»cte spike analysis on the unfiltered itpF~er tailings <br />pond sample. The result for this spike recovery analysis was 87%, which is ~~vithin the <br />acceptable guidelines for spike recoveries for cyanide (75-].25%). 'The unfiltered upper <br />tailings pond total ryanide concentration reported in the Analytical Report is 680 u,g/I, while <br />the original value reported in the Quality- Control Report is only 220 µg/1 I;page 26). <br />According to Core Laboratories (personal) cotnmtirtication, T yn Benkers, 7/1.5/93)), this is <br />because thc: sample was diluted 1:3, and the actu<d analyzed concensation (not corrected <br />for dt7utionl was reported. The spike added was 80 µ,g/1 and the analyzed value was 290 <br />µg/1. The original value is 220 µg/1, and the %R is 87%. Given the problems with WAD <br />and total c:yar»de and the noted differences in cyanide concentrations in filtered and <br />unfiltered samples, it would be important 1:o conduct spike recoveries on every process point <br />sample, especially unfiltered samples. <br />3.4 LABORATORY TURNAROUND 'I7ME <br />The laboratory turnaround time was ;somewha.t improved for this sampling. Core <br />Laboratories received the samples on Aprt7 29, 1'993. The date of the Analytical Report <br />from Core Laboratories was May 27, 199:1, which is a turnaround time of slightly under one <br />tnontt:. <br />4.0 CONCLUSIONS AND RECOMMENDATIONS FOR FUTURE <br />SAIVIPLING <br />- Groundwater well samples were collected on this monitoring trip, and all <br />cyanide concentrations were below detection: <br />- WAD cyanide concentrations were higher than total concentrations in both <br />unfiltered and filtered lower tailings pond samples. Tots] cyanide <br />concentrations were higher in filtered titan unfiltered sample:: for both the <br />upper tailings pond and the lower tailings pond samples. WAD cyanide <br />concentrations were also higher in filtered than in unfiltered samples at these <br />same locations. These xesultsutdicate that fairly significant analytical <br />problems still exist with cyanide determinations in samples from the site. <br />Given the problems with W,AD anti totid cyanide and the noted differences <br />in• ryanide concentrations in fitere;d and unfiltered samples, it would be <br />important to conduct spike recoveries on every process point sample, <br />especially unfiltered samples. <br />RCG/Hagler, liailly, lac <br />