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introduced to the mine water at the static mixer, as <br /> flocculant and water enter the 2 ,000 gal . dynamic mixing <br /> tank. <br /> Flocculated water gravity flows from the tank to the 020 <br /> pond through a pipe, which extends from an upper story <br /> of the wash plant, to the pond. The pond is indicated <br /> on Map II-B-7. <br /> The pond is used as a "finishing" or clarification pond <br /> for the -200 mesh solids. <br /> The 020 pond is presently under-utilized. It was <br /> originally designed to provide sediment control for the <br /> underground storage bunkers, on which construction has <br /> been delayed. On proceeding with construction and <br /> installation of the storage bunkers, Mid-Continent will <br /> review adequacy of the pond for sediment control, given <br /> its usage as a finishing pond. If necessary, at that <br /> time, Mid-Continent will provide additional sediment <br /> control facilities for run-off from the storage bunkers. <br /> As indicated on Attachment 2 , the 020 pond has a volume <br /> of 39, 830 ft3 . Retention time, assuming an inflow of <br /> 1,000 gpm, is 4 . 92 hours. <br /> As indicated in Table 1, the average volume of solids to <br /> the 020 pond is estimated at 36 tons per month; or 429 <br /> tons per year. <br /> The pond will be cleaned, as necessary, so that sediment <br /> load does not exceed 60% of volume. Sludge removed from <br /> the pond will be disposed in the approved refuse disposal <br /> area. <br /> The system is equipped with automatic alarms and shut- <br /> off devices. The control panel is located in the <br /> preparation plant. Instrumentation for the treatment <br /> plant includes indicator lights for hyroclone pump, <br /> agitators and flocculant feeder, local on/off switches <br /> for pumps and agitators and motor trips. <br /> After treatment in the plant and "finishing" in the 020 <br /> pond, the mine water will be discharged from outfall 020 <br /> into Coal Creek. <br /> Water treatment alternatives. Mid-Continent proposes <br /> installation of a system which would allow a number of <br /> alternatives for treatment of mine drainage. The <br /> pipeline which now extends to the preparation plant area <br /> allows us, on permit permission, and with the <br /> installation of some additional piping, to manage mine <br /> 4 <br />