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5 high-than-normal temperatures maintained in the aeration chamber. These higher temperatures make the waste more readily digestible by the active organisms. The temperature is elevated by a combination of three things: the heat dissipation/transfer of the submerged pump, the energy conversion which takes place during the digestion process, and the retention of both of these heat sources by closed tanks. As the height of the mixed liquor increases in the aeration chamber, a float switch starts the system microprocessor which, in turn, starts the mixed-liquor transfer pump (MLT) and transfers a fixed volume (batch) of mixed liquor to the. clarifier. The MLT pump is controlled by time, and the actual programming allows for two or three minutes ' pump overrun to overflow the MLT into the weir, which skims off the scum and other floatables. These floatables are returned to the- aeration chamber for reprocessing at each batch cycle, or 14 times per 24-hour day. Batch time in the clarifier is determined by the amount of time necessary for the remaining bacteria and dead cells, which flock together once deprived of food and oxygen, to settle, separating the supernatant from the sludge. This time period is sufficient to allow flocculation and settling, but is not long enough to encourage an anaerobic condition. Average time is between 60 and 70 minutes. Coagulants are not needed, nor are they recommended. After settling has occurred, the microprocessor switches on the supernatant transfer pump (SNT) , which pumps the supernatant into the chlorine contact chamber. While the supernatant is in transit, chlorine is injected into the transfer line. By injecting chlorine directly into the transfer line, short circuiting, which can take place when chlorine is injected into the contact tank, is prevented. Chlorine injection is regulated to give maximum pathogen kill with minimum. residual chlorine remaining. All residual chlorine is converted to chlorate during the ozonization stage thus making the discharge completely safe for use in lakes or ponds containing marine life. After the SNT pump transfers the supernatant from the clarifier, the clarifier sludge return (SLR) pump returns the sludge from the clarifier to the aeration chamber for reprocessing. This returning of sludge takes place 14 times in every 24-hour period. The returned sludge, along with the fresh incoming waste, becomes the food source for new cell growth and a carbon source for denitrification, which takes place in the aeration chamber. This returning of 100% of the sludge for reprocessing 14 times per day is the reason the Bio-Pure systems generate very little disposable sludge. Because of this .100% returned-sludge process, the Bio-Pure system is capable of removing an average of 96.4% of nitrates. The 100% returned activated sludge (RAS) provides dead bacterial cells +3 as the carbon source for new cell growth. These new cells utilize the NO3 , along with the PO causing denitrification. The dead