A Canadian township uses dewatering units to achieve septage disposal compliance - Case Study
In 2002, Ontario, Canada's legislature and the Ministry of Environment (MOE) produced a policy paper announcing their intent to eliminate the land application ofuntreated septage. While 90% of residents in Ontario used local sanitary sewers to dispose of their waste and therefore were unaffected by the policy, there were still more than one million residents in rural areas using septic tanks.
Haulers across Ontario were left in a bind, scrambling to find methods to treat and dispose of the scptagc. It was up to the local municipalities and the private haulers to come up with alternate methods to treat and dispose of the scptagc. For the small town of Eganvillc (population 3,455), located in Bonncchcrc Valley, the solution was found in Gcotubc dewatcring containers.
The Gcotubc idea originally was presented by an Eganvillc resident. Don Bishop, a Gcotubc manufacturer's representative. understood the benefits of dewatcring technology and recognized the potential for a scptagc treatment application in his hometown.
In Fall 2004, at the Eganvillc Wastewater Treatment Plant (WWTP), Bishop presented a dewatcring and containment demonstration for community leaders and public officials.
'The municipal leaders were impressed with the simplicity and cost-effectiveness of the Gcotubc technology,' Bishop said. 'The next step was to conduct further testing.'
The Eganvillc township first trial-tested Gcotubc dewatcring technology in a small pilot project, processing about 21,000 gal of septic tank waste in July 2005. A Gcotubc unit measuring 22 ft by 22.5 ft was filled and allowed to dewater through the winter months. Moisture continued to drain from the septage material. At the conclusion of the pilot test, the solids content of the septage in the unit had risen from 3% to almost 40%.
The dewatering outcome was expected; the quality improvement of the septage material, however, was a huge surprise. The pathogen content of the solids declined significantly. This most likely was due to the composting effect of holding the waste inside the Geotube container. Not only did the unit successfully dewater the septage, the lab results of both the effluent and retained solids were impressive.
The effectiveness of dewatering containers, along with the simplicity and affordability of the technology, encouraged Bonnechere Valley to implement these units as a long-term solution for the treatment of septage and biosolids from the WWTP.