"The Eco Machine is enclosed in a greenhouse kept at a constant 80°F throughout the year. A screen over the glass closes at night to retain heat. Andrew Posner, Operations Manager, performs all the tests required of a small wastewater treatment plant and reports that the system consistently meets its goals: BOD<30, TSS<30, TN<10 as well as state standards for heavy metals.

Wastewater entering the system flows into a 16,600 gallon blending tank. From there it is pumped to a splitter box where water is directed into one of six treatment trains. Each train contains four tanks, 6 feet high and 6 feet in diameter capable of holding 1,100 gallons. Tanks are open at the top with floating racks constructed of PVC, holding an array of plants (usually 8 or 9 different species). Depending on the nutrients available, one plant tends to dominate in each tank.

After traveling through those four tanks, which takes about half a day, the wastewater hits a clarifier - an 11 foot tank that holds about 6,000 gallons. There bacteria and other debris settle out within three hours. Clean water runs by gravity to a sand filter and then into a constructed wetland, planted with tropical plants such as cana lilies and banana trees. Posner describes harvesting bananas, grown with the treated wastewater, in the middle of a Massachusetts winter.

After the wetland, water runs into a UV disinfection unit and is discharged to a leachfield a quarter of a mile away. Stringent regulations were imposed by the state of Massachusetts as a condition for the facilities' permit due to concerns for nearby wetlands. To date, the AEES has met them all.

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