TECHNOLOGY FOCUS - CERAMICS AND GLASS - Preferred Component: The filter media comprise a bed of coarse round, silica sand having a diameter of 2.5-3.5 mm.    TECHNOLOGY FOCUS - ENVIRONMENT - Preferred Component: The system includes a bioreactor vent pipe outletting the bioreactor interior above a ground surface to an ambient atmosphere; an air pipe inserted through the bioreactor top, through the bioreactor interior, through the filter media and gravel bed. The air pipe is interconnected to an aeration assembly on the ground surface, and is adapted to provide aeration of the sand filter. The aeration assembly has backwash blowers and process blowers. An outlet backwash line is inserted through the bioreactor side wall above the filter media. It is interconnected to a system headworks at the equalization influent inlet. The equalization tank outlet is positioned vertically lower than the equalization tank inlet. The clear well first inlet is positioned vertically lower than the equalization tank outlet. The first pump system pumps a liquid from the clear well interior back up through the clear well first inlet, clear well inlet pipe, into the bioreactor interior, through the gravel bed and sand filter. The reverse flow fills a bioreactor head space in the bioreactor interior above the filter media. The liquid in the filled bioreactor head space flows back through the sand filter into the clear well. Aeration diffusers are in the clear well interior adjacent to the clear well bottom. A process air is interconnected to the air pipe and connected to the aeration diffusers. Remotely controlled electrically activated valves are in the air pipe and process air pipe. They control air flow through the air pipe and process air pipe. The gravel bed is positioned on the underdrain and the filter media positioned on the gravel bed. A check valve is in the equalization tank outlet to prevent a reverse flow from the bioreactor into the equalization tank. A membrane microfiltration unit is attached to the clear well discharge outlet.