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4 <br />3.0 SUMMARY AND ASSESSMENT OF ANALYTICAL ACTIVITIES <br />3.1 ANALYTICAL RESULTS <br />The field parameters and analytical results are displayed in Tables 2 and 3, respectively. A <br />discussion of any elevated concentrations or unusual results and comparison to previous <br />results is provided below. <br />3.1.1 Surface Water <br />RS-5. RS-5 had a lower conductivity than the April sample, which is reflected in slightly <br />lower concentrations of calcium and sodium. Total and WAD cyanide were again below <br />detection (at 20 µg/1) at this location. Iron concentrations were the highest rrleasured thus <br />far for the third-party monitoring. Under the oxidizing and near-neutral pH conditions of <br />the stream, it is likely that much of the iron is in the colloidal or suspended form. <br />3.1.2 Process Points <br />Total cyanide concentrations were again highest in the Collection Pond and were above <br />detection in all process point samples. WAD tyanide concentrations were above detection <br />in all process point samples and were the highest measured in the upper and lower tailings <br />impoundment samples thus far for the third-party monitoring trips. However,liJAD cyanide <br />was higher than total cyanide in both tailings impoundment samples. <br />Upper Tailings Pond. WAD cyanide concentrations were approximately five times higher <br />than total cyanide concentrations in the upper tailings impoundment samples. Core <br />Laboratories noticed this discrepancy after the 14-day holding time for cyanide had elapsed <br />(see Appendix E), but conducted reanalyses of both total and WAD cyanide oni the samples. <br />The recheck (Table 3) analyses showed approximately equal concentrations of total and <br />WAD cyanide in the upper tailings impoundment samples, but these results are invalid <br />because of the exceedence of EPA holding times. Calcium and sodium concentrations are <br />higher than they were in April, which is likely a reflection of increased evaporation as <br />reflected in a higher conductivity value in May. Temperature and pH were alsd significantly <br />higher in May, which likely reflects decreased concentrations of COZ in the impoundment <br />water. Copper and iron concentrations were approximately half that of the April sampling. <br />The lower metal concentrations are most likely due to increased pH values. <br />RCG/Hagler, Bailly, Inc <br />