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10 <br /> It was determined if a seed was provided for the flocs, we could achieve acceptable settling rates. <br /> initially, 9 tailin was used as the seed particle, it was determined that the WWTP could be economically <br /> converted to a lime system. It was determined that the goal really was to enlarge the same process that <br /> was in the WWTP building and that it was not necessary to perform this treatment inside a building. If a <br /> little settling was good, then a lot of settling was better, and it was felt this could be accomplished on a <br /> tailing pond. This would solve almost all of the operational problems, replacing a thickener with passive <br /> settling, and removing most of the operational manpower. <br /> In retrospect, this seems so obvious that one wonders why it took so long to make the <br /> determination. But in fact, everyone involved with the WWTP, including,the regulatory agencies, was <br /> focused on a process that fit the conventional wisdom of treatment plants. Convincing the regulatory <br /> agencies that the Company was not evading some obligation or responsibility by moving treatment to the <br /> tailing ponds and shutting down the WWTP was a large hurdle. With the tentative blessing of the State, a <br /> test of the new treatment system was begun. <br /> The water pool on the tailing pond farthest downstream, into which virtually all water reported, <br /> became the treatment system. Working with a local limestone kiln, baghouse dust was utilized to raise the <br /> water pool pH. This kiln dust was a low grade quicklime which, because the kiln was coal fired, also <br /> provided flyash which served as the seed particle for flocculation. The water pool contained 5.5x101 m9, <br /> which was raised to pH 10.8 to provide manganese removal. The water was decanted from the pond <br /> using existing decant facilities, and since the decant line discharged near the WWTP, the sulfuric acid <br /> pipeline and ph controls were available for neutralization. Lime addition began in the summer of 1985. <br /> The cost of raising the pH of the water pool was approximately $300,000. <br /> By October, 1985 it was proven this was a concept that was working and in fact, so much settling <br /> time was available that water quality was better than that from the WWTP. This system is now permitted <br />