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9 <br /> It was quickly determined that the issue of "wet" years vs "dry" years did not matter. There was <br /> far more water to treat than anticipated. The shutdown year of 1983 was the first full year the Climax <br /> Mine had been shut down since 1923. These current cutbacks and shutdowns put severe strains on the <br /> discharge system. The WWTP was performing.as good as it could, but there was great concern as <br /> personnel tried to cope with the excess water that required treatment. The State was unhappy because <br /> the Company was continuously in an Emergency bypass situation simply to maintain the stability of the <br /> tailing ponds. It was obvious to everyone that an expansion of the WWTP was required, but the cost <br /> estimates were well over $20 million. Faced with poor markets for molybdenum, the Company was not <br /> eager to invest that amount of money in treatment facilities. <br /> In 1985, research was begun on how best to enlarge the WWTP. Actual measurements of flows <br /> showed a need to treat at least 315 I/s to be able to maintain a water balance and that wet year flows <br /> would be in the range of 440 to 568 I/s. It appeared feasible to utilize the mill facilities from both a <br /> volume and chemical standpoint, and the only drawback was this solution did not take into account the old <br /> mine drainages in the tailing area. Settling rates were the key to making the thickeners work, and work <br /> focused on that issue. <br /> Settling was originally considered in the early 1970's prior to deciding on ion-exchange and <br /> ElectroClear methods. It was discarded due to the temperature characteristics of the water, which hovers <br /> close to freezing most of the time. In the hottest months of summer, July and August, water temperature <br /> rises to 4°C. Most of the year, it is 1°C, and in the coldest months, the water temperature is -1*C. To <br /> utilize lime hydroxide precipitation, it would be necessary to effectively settle the precipitates. <br /> Unfortunately, research indicated that when the water was at its coldest temperature, the density of it <br /> changed sufficiently that it approached the density of the light hydroxide floc particles. This created a <br /> settling problem and concern that in the winter time, settling could not be achieved. <br />