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6 nitrate+nitrite and phosphorous. It is possible that samples with higher alkalinities may require more preservative to reach the desired preservation pH values. 3.0 SUMMARY AND ASSESSMENT OF ANALYTICAL ACTIVITIES 3.1 Analytical Results The field parameters and analytical results are displayed in Tables 3 and 4, respectively. A discussion of any elevated concentrations or unusual results is provided below. RS-5. The total aluminum and silver concentrations (160 and 30 µg/1, respectively) are relatively high for a stream with a pH as high as 7.96. Total aluminum concentrations are over three times the detection limit Total silver concentrations are three times the detection limit. Without knowing mere about natural background conditions, it is impossible to determine the cause cf these metal values. Cadmium concentrations were below detection at 5µg/1. Process Points. Total cyanide concentrations in the lower tailings pond, upper tailings pond and the collection pond/duplicate were 0.58, 0.24 and 8/7.9 mg/1, respectively. WAD cyanide concentrations were 0.56, 0.2 and 7.9/7.8 mg/1, respectively in these same process points. Dissolved copper concentrations were 1.72, 2.33 and 17.4/18.9 mg/1 in the lower tailings, upper tailings and collection ponds, respectively. Field and Rinse Blank. The field blank (BMRI DI water) had somewhat elevated concentrations of iron (80 µg/1), silica (34.5 mgp) and zinc (20 µg/I). The rinse blank had somewhat elevated concentrations of iron (30 µg/I), but they were below those in the field blank. Groundwater Wells. Well M-13 had a cyanide concentration of 30 µg/l, which is above the detection limit of 20 µg/1; WAD cyanide was below detection. According to Core Laboratories, 20 µg/t is the appro~dmate practical quantitation limit (PQL). The instrument detection limit for this vety sensitive colorimetric technique is approximately 5 µg/I (personal communication, Lyn Benkers, Core Laboratories, 4/15/93). This well also had a silver concentration (60 µg/I) that was higher than that of the other wells or RS-S. Dissolved copper concentrations in well M-12 (20 µg/l) were higher than in the other wells, which were below detection in copper. RCG/Hagler, Bailly, Inc.