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11 <br /> at 568 I/s, and has been successfully tested at double that rate. Operational costs of this system are <br /> approximately S0.05/m3 treated. <br /> It would be nice to report that this solved all issues including snowmelt bypass, but it did not. The <br /> snowmelt bypass provisions are still required. Beginning in 1986, although we needed the snowmelt <br /> bypass provision to remove excess water in the spring time, it was found the new treatment system met <br /> "all season" standards even during snowmelt bypass. The snowmelt bypass provision remains in our <br /> permit, but now, rather than utilizing it for quality considerations, it is utilized exclusively for flow <br /> considerations in the spring. Although discharge can be performed at an acceptable average flow rate <br /> through out the year, it is not prudent to do so in the fall and early winter due to the unpredictability of the <br /> snow fall. It is possible to discharge at a high rate, have a "dry" winter, and have depleted the process <br /> water supply to the point that mill operations would be restricted. The solution has been to keep the <br /> discharge flow rate at a reasonably low level to accommodate the stream during the winter, releasing more <br /> 1 treated water in the spring. With all discharges now meeting the "all season" standards, this has an <br /> overall smaller impact on the stream. Discharges now pass EPA's Whole Effluent Toxicity Test. <br /> Discharges now routinely meet the 30-day total recoverable limits of 1.0 mg/kg iron, 0.044 mg/kg copper, <br /> 1.0 mg/kg manganese, 0.17 mg/kg zinc. Aquatic studies and fishermen indicate the stream is returning to <br /> a cold water fishery; something it has not been for well over one hundred years. <br /> Future Issues <br /> There are number of issues that remain to be addressed, and a number of opportunities from which <br /> advantage may be taken. Although treatment costs have dropped significantly from the original costs, <br /> cost cutting remains as a goal. Liquid CO2 has been tested as a pH modifier, but has not yet been pursued <br /> due its creation of minor turbidity problems. Future modifications will address both the issues of lime <br /> efficiency and a method to better handle the voluminous lime hydroxide sludge. Shortcircuiting is of <br />