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very small. A decreasing trend in sodium had been observed at well GP-6 until a small <br /> increase in the last three years. Declines in sodium concentrations at well GF-7 occurred <br /> from 1989 to 1996 with slightly higher values the last three years. Sodium concentrations <br /> are much smaller in backfill well GF-11. The SAR values observed in 1999 in water in the <br /> Trapper wells was very similar to recently observed and natural values at Trapper Mine. <br /> None of the 1999 SAR values indicate a significant trend in this parameter. <br /> The heavy metals with a T' subscript by their symbol represent total <br /> measurements, while the others are dissolved concentrations. Dissolved and total <br /> concentrations are similar for most of the heavy metals, except for iron concentrations in <br /> some wells where the total values are significantly greater. <br /> Iron concentrations have varied over large ranges near the mine pits and at distant <br /> wells but no consistent trends have been observed. Levels of aluminum, barium, boron, <br /> phosphate and manganese have also varied over significant ranges but no consistent <br /> trends have been observed. Arsenic, cadmium, chromium, copper and lead concentrations <br /> have been low with a few exceptions. Copper concentrations in wells GB-5 and GE-3 have <br /> been higher mainly prior to mining. Early on, a few elevated lead concentrations were also <br /> observed in wells GE-1 and GE-2. Molybdenum, nickel, selenium and vanadium <br /> concentrations have stayed low, except for a slightly higher selenium value in well P-3. <br /> The laboratory indicated that the selenium value is an estimate due to matrix interference. <br /> The recent radium 226 values have been low. <br /> • <br /> 3-11 <br />