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11 estimated and makes it difficult to assess whether total cyanide concentrations were higher than WAD ryanide concentrations in a sample, although total cyanide was clearly higher than WAD ryanide in the collection impoundment sample. Resampling of the tailings impoundments for total cyanide analyses is not recommended because, even though the values are estimated, the October 1993 concentrations do fall within previously measured values. - Core Laboratories noticed that acceptance criteria for tailings impoundment lab duplicates were not met after the 14-day holding time for cyanide had elapsed, but conducted reanalyses for total cyanide on these samples. The reanalyses are estimated values only because of exceedence of recommended holding times. - Core Laboratories analyzed well sample M-9 for total cyanide two days beyond the 14-day holding time and reported a total ryanide concentration below the detection limit of 20 µg/1. This resulted in the rejection of this value. However, unlike well M-13, well M-9 has never had a measured total or WAD ryanide concentration that was above detection. Consequently, resampling is not necessary. - High spike recovery percentages (above control limits) were reported far both total and WAD ryanide analyses for the collection impoundment sample. Core Laboratories ascribes this to the dilution required far sample color. Dilution of another aliquot of the sample prior to spike addition would have circumvented this problem. - Core Labs was requested to perform spike recovery analyses on unfiltered process point samples and to evaluate all total and WAD ryanide analyses on the three process point samples before the 14-day holding timE: elapsed so that meaningful reanalyses can be conducted. However, rechecks were conducted after the ]4-day holding time had elapsed, resulting in estimated data. RCG/Hagler Bailty