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2 L The water is drawn from this tank by Redux' process pump. This pump will take the untreated stream and pressurize it to 60 psi . The water will them flow into an air dissolving tank <adt> which is used to control the injection of air into the waste water. The adt has flow control valves and regulators for the incoming air and a continuous air bleed system which rids the system of air which does not dissolve into the water. There is also an emergency air pressure relief system to prevent pipeline damage in the event that the system pressure surpasses 125 psi. Coming out of the air dissolve tank the water continues through a pressurized reaction zone called a serpentine. This section of pipe uses velocity to further mix the coagulant chemical and the water. Following the serpentine the water flows across the main flow control valve. This valve is what maintains system pressure and the flow rate of the DAF system. On the down side of the flow control valve the water is at atmospheric pressure. A flocculant chemical is then added to draw together the coagulated contaminants so they may be readily floated in the clarifier. The water flows into the bottom of the clarifier and the air which was in solution is now coming out of solution forming millions of minute air bubbles. These air bubbles attach to the flocculated particles and lift them to the upper portion of the clarifier where it is dispositioned for further treatment called dewatering. The treated water, which is in the lower portion of the clarifier gravity flow out a pipe and caught in a tank where is pumped the next part of the process. (see attachment "B" ) The water is transferred to a sand filter for final polishing. Polishing is a term used to describe the removal of fine particulate which may not float to the top of the clarifier and become entrained in the treated water exit line. The removal of these particulate provide for a high quality effluent which is more than adequate for reuse. The sand filter is designed to handle the full flow rate with a margin of excess for safety. The sand filter will typically operate at a psi range of 10 to 15. When the pressure begins to exceed 15 the system operator will put the filter into backwash mode to clean the bed of sand. Its operating principles are very similar to the type used on domestic swimming pools. The backwash water is piped back to the dirty water storage tanks where the water will be retreated. Coming out of the sand filter the water is then stored in an above ground polyethylene tank until required to be used for the washing of trucks.