(Credit: MPCA)The Minnesota Pollution Control Agency (MPCA) has purchased new technology to remove and destroy bulk concentrations of per- and polyfluoroalkyl substances (PFAS) from contaminated water in the environment. This fall, the state will deploy the technology in the East Metro area as part of the ongoing work to address PFAS contamination affecting the drinking water for roughly 174,000 residents. The system is paid for with funds from the 3M settlement.
According to the Environmental Working Group (EWG), the known extent of contamination of American communities with the toxic fluorinated compounds known as PFAS continues to grow at an alarming rate, with no end in sight. As of March 2019, at least 610 locations in 43 states are known to be contaminated, including drinking water systems serving an estimated 19 million people.
The process works in two parts. The first technology, surface activated foam fractionation (SAFF), injects outdoor air into contaminated water, turning PFAS into foam that can be separated from the water. The foam is then removed, PFAS levels are significantly reduced, and the water is returned to the environment. The PFAS concentrate then goes to the Defluoro unit, a second technology where the carbon-fluorine bonds (the backbone of PFAS chemicals) are broken through electrochemical oxidation. Both technologies are mobile and work without adding any chemicals back into the surface or groundwater.
Australian-based OPEC Systems, Ltd. designed the SAFF technology. US-based Aecom designed the Defluoro unit.
With fewer than 20 systems in existence, the SAFF technology is in high demand across the globe for its ability to separate PFAS from water safely and quickly. Minnesota is the first state government in the country to purchase and implement it. The SAFF unit will deploy at Tablyn Park in Lake Elmo for the first round of testing on groundwater and surface water. It will likely move to other testing locations over the next one to two years. The Defluoro unit will be staged at the former Washington County landfill location.
