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7 <br />Lower Tailings Pond. As was the case for the upper tailings impoundment samples, Core ~. <br />Laboratories did not notice that WAD cyanide concentrations were higher than total cyanide <br />until after the 14-day holding time had elapsed. The samples were rerun and found to have <br />approbmately equal concentrations of WAD and total cyanide. However, as discussed <br />above, these values are not valid. The results for the April sampling also showed that WAD <br />cyanide concentrations were higher than total cyanide, and the rechecks of those samples <br />also showed lower concentrations upon reanalysis. Althoughwidely-acknowledged problems <br />associated with the analysis of WAD cyanide would tend to cast more doubt on the WAD <br />cyanide values, it is impossible to discern without further analytical work whether the total <br />or the WAD cyanide concentrations (or either) in the tailing impoundment samples is <br />correct. Concentrations of calcium, copper, iron, sodium and zinc were similar to those <br />measured during the April sampling, although calcium and sodium concentrations were <br />higher in May. <br />Collection Pond. Both total and WAD cyanide concentrations were the highest measured <br />since the November third-party sampling trip. Unlike in the tailings impoundment samples, <br />the WAD cyanide concentration was not higher than the total cyanide concentration. The <br />collection pond again had the highest measured cyanide concentrations of the process point <br />locations. Concentrations of calcium, copper, iron, sodium and zinc were slightly lower than <br />but similar to those measured in April. <br />3.1.3 Groundwater Samples <br />Groundwater Wells. Both total and WAD cyanide concentrations were again below <br />detection (at 20 µg/1) in all groundwater samples. Metals concentrations will'be discussed <br />below. <br />MM=9. M-9 again had the highest calcium and sodium concentrations of the three <br />groundwater samples. Calcium, copper, iron, sodium and zinc concentrations were very <br />similar to those measured in April, with copper, iron and zinc concentrations again al] below <br />detection. <br />M-12. Copper, iron and zinc concentrations were also below detection in M-12. Calcium <br />and sodium concentrations were similar to those in well M-13 and lower than those in well <br />M-9. <br />M-13. Duplicate samples were again taken at well M-13, in part because of the cyanide hit <br />in the November sampling. Total and WAD cyanide were both below detection. Duplicate <br />analyses were all within ±20%RPD, although the iron values were within 17%. Copper and <br />zinc concentrations were below detection. Iron concentrations were significantly above <br />detection; concentrations in the April samples (filtered) were below detection. The iron <br />measured in M-13 is most likely in the colloidal or suspended form. <br />RCG/Hagler, Bailty, Inc <br />