Treating PFAS with Containerized Water Treatment Systems at a Royal Australian Air Force (RAAF) Base
Historical use of aqueous film forming foam at Royal Australian Air Force (RAAF) Base Tindal in the Northern Territory, Australia has led to per- and polyfluoroalkyl substances (PFAS) contaminating the local aquifer, which supplements the nearby community’s drinking water supply during the dry season. The remote location of the site and the scarcity of waste disposal and treatment facilities necessitated the use of an innovative process for PFAS remediation in order to minimize the amount of waste generated. As part of its response to the contamination, the Australian Department of Defence engaged ECT2 to provide dual containerized water treatment systems and a central regeneration facility to enable media reuse.
ECT2 first installed a 200 gpm modular water treatment system at each of the the two main groundwater source areas on the RAAF Base property. Maximum influent PFAS concentrations in the two areas are up to 40-50 ug/l. Regenerable ion exchange (IX) resin is used to remove PFAS compounds from the water using a lead/lag/polish treatment train arrangement.
The regeneration facility, installed adjacent to one of the water treatment systems, utilizes ECT2’s patented regeneration process which removes PFAS from the IX resin using a solvent-brine blend. Following media regeneration, the regenerant is recovered and the PFAS is superloaded into a highly concentrated solid waste.
Over 18 months and 815 million liters of PFAS-contaminated water treated, there have been no detections of PFOS, PFOA, or PFHxS in exceedance of the Health Based Guidance Values in the water discharged from either of the treatment systems. A stringent controls and remote monitoring scheme allows the plants to operate 24/7 with a combined uptime of 99.4%. Owing to the innovative process design and regenerable IX resin technology, waste generation has been limited to approximately 1 liter per 10,000,000 liters of PFAS-contaminated water treated.