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4 3.0 SUMMARY AND ASSESSMENT OF ANALYTICAL ACIIIVITIES 3.1 ANALYTICAL i1tESiJLTS The 5eld parameters and analytical results are displayed in Tables 2 and 3, respectively. A discussion of any elevated concentrations or unusual results and comparispn to previous results is provided below. 3.1.1 Surface Water RS-5. Total and WAD ryanide were again below detection (at 20 µg/1) at this location. The nitrate+nitrite concentration was below detection at 0.05 mg/1, which was lbwer than that detected in November (100 µg/1). The calcium concentration (19.6 mgjl) was similar to that of the March sample but approximately half that of the November sample; the copper concentration was again below detection (at 10 µg11). The iron concentration was approximately twice that of the March and November samples. Sodium and zinc concentrations (4.2 and 0.01 mgA, respectively) were nearly identical to those in November and March. 3.1.2 Process Points Total cyanide concentrations were highest in the Collection Pond and above detection in all process point samples. WAD cyanide concentrations were above detection 'in all process point samples except in the Upper Tailings Pond; however, dissolved WAD cyanide was hieher than total WAD ryanide in this sample. In some cases total and/or WAD cyanide concentrations were higher in filtered than in unfiltered samples, and in two samples WAD ryanide was higher than total cyanide. Comparisons of 5ltered and unfiltered samples and of total and WAD ryanide concentrations will be discussed below. Upoer Tailings Pond. In the upper tailings pond filtered samples had higher concentrations than unfiltered samples for both WAD and total cyanide. WAD cyanide concentrations were lower than total ryanide in both 5ltered and unfiltered samples. The higher concentrations in the 5ltered samples may indicate that there are analytical interferences for both WAD and total ryanide in the unfiltered samples. Nitrate+nitrite, calcium, copper, iron, sodium and zinc concentrations were very similar to those in samples froum the March trip, Total metal concentrations were within 10%RPD of dissolved metal concentrations with the exception of iron and zinc values. The higher iron concentration in the unfiltered sample again indicates that colloidal iron is present in the upper tailings pond. Zinc concentrations are very close to the detection limit (0.01 mg/1), but higher concentrations of zinc in all three process points may indicate that colloidal zinc also exists in the upper tailings pond. RCG/Hagler, 13ailly, Inc.