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that are greater than 1.0 mg/l in 2013. Several of these wells are located away from mining and <br />contain natural levels of NH3 concentrations. All of the NH3 concentrations observed in 2013 are <br />within the natural range of this constituent at Trapper Mine. <br />All of the 2013 NO3 values were below the drinking water standard of 10 mg/l. Well P -3 has <br />historically contained nitrate concentrations above 10 mg/1 but this well was dry during the 2013 <br />sampling. <br />3.5 OTHER CONSTITUENTS <br />The major constituents other than bicarbonate and carbonate are presented on pages B -111 <br />through B -163. Declines in sodium concentrations at well GF -7 occurred from 1989 to 1996 with <br />slightly higher values in recent years. Sodium concentrations are much smaller in backfill well GF- <br />11. The SAR values observed in 2013 in water in the Trapper wells were very similar to recently <br />observed and natural values at Trapper Mine. None of the 2013 SAR values indicate a significant <br />trend in this parameter. <br />The heavy metals with a "t" subscript by their symbol represent total measurements, while <br />the others are dissolved concentrations. The "tr" subscript for iron indicates total recoverable iron. <br />Dissolved and total concentrations are similar for most of the heavy metals, except for iron <br />concentrations in some wells where the total values are significantly greater. <br />Iron concentrations have varied over large ranges near the mine pits and at distant wells but <br />no consistent trends have been observed. Levels of aluminum, barium, boron, phosphate and <br />manganese have also varied over significant ranges but no consistent trends have been observed. <br />Arsenic, cadmium, chromium, copper and lead concentrations have been low with a few exceptions. <br />Trapper Mining Company 3 -9 <br />2013 Annual Report <br />