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d 3.0 SUMMARY AND ASSESSMENT OF ANALYTICAL ACTIVITIES 3.1 ANALYTICAL RESULTS The field parameters and analytical results are displayed in Tables 2 and 3, respectively. A discussion of any elevated concentrations or unusual results and comparison to November results is provided below. 3.1.1 Surface Water RS-5. The nitrate+nitrite sample was collected but not analyzed because nm cyanide was anticipated at this location based on previous analyses. In November, the tlitrate+nitrite concentration was 100 µg/l. Total and WAD cyanide were again below detection (at 20 µg/1) at this location. The calcium concentration was approximately half that of the November sample; the copper concentration was again below detection (at 10 µgJl). Iron, sodium and zinc concentrations were nearly identical to those in November. 3.1.2 Process Points Total and WAD cyanide concentrations in al] process point samples were abpve detection (at 20 µg/1). Comparisons of filtered and unfiltered samples and of total and WAD cyanide concentrations will be discussed below. Lower Tailings Pond. As anticipated, unfiltered samples had cyanide concentrations (both total and WAD) that were equivalent to or higher than those in filtered samples. However, WAD cyanide concentrations were greater than total cyanide concentrations in both filtered and unfiltered samples from the lower tailings pond (Table 3). This indicates that there is still an analytical problem with the WAD and/or total cyanide deterntinati4ns. For the metals, total concentrations are approximately equal to dissolved concentrations (within "±10%) with the exception of iron. Dissolved iron concentrations are below detection (at 30 µg/1), while total iron concentrations are 370 µgQ. The difference in iron concentrations in the filtered and unfiltered samples indicates that there is considerable irdn present as colloids in the lower tailings pond. LJnoer Tailings Pond. As expected, in the unfiltered sample total cyanide concentrations were higher than WAD cyanide concentrations. However, in the unfiltered sample the WAD cyanide concentration was seven times the total cyanide concenteation, again indicating that analytical problems with the WAD cyanide method at this site. In comparing filtered and unfiltered samples, as expected, the total cyanide concentration in the unfiltered sample was higher than in the filtered sample, but the WAD ryanide concentration in the unfiltered sample was only half that in the filtered sample. This again suggesrts that RCG/Hagler, Badly, Inc