Demonstration System Tour: Property TRF2

Technologies: SeptiTech and Bottomless Sand Filter

For more information on trickling filters: This type of technology is designed and manufactured by several companies. Please see vendor website for this particular system at www.septitech.com.

Year Installed: June 2003

Site Description:

• 9,000 sq ft lot, 2-bedroom house, 2-4 residents, seasonal use (design flow: 300 gallons per day)
• Wetlands within 200 ft of system
• Glacial till soils
• Limiting factors: Water table within 38” of the surface; Adjacent to Green Hill Pond
• Public water supply
• Previous system: cesspool

System Treatment Train:

Wastewater flows by gravity through a building sewer (A) from the house into a septic tank (B) where solids separation occurs. Wastewater then flows from the septic tank into the trickling filter (C), where four pumps are located. The first pump doses wastewater to the top of media pillows containing polystyrene beads. Wastewater trickles through the media and flows by gravity back into the sump area of the tank. This recirculation process will reoccur several more times. A second pump transfer some effluent to the head works of the septic tank for denitrification (D), and a third pump transfers accumulated sludge to the inlet of the septic tank (E). Treated final effluent is pressure dosed by a fourth pump to a bottomless sand filter (F) for final dispersal and treatment. All these processes are controlled by a programmable logic control that time doses all the events.