The historical use of fire-fighting foam at the Royal Australian Air Force (RAAF) Base Tindal led to groundwater contamination with various per- and polyfluroroalkyl substances, commonly known as PFAS. These compounds are commonly found in fire retardants and several other products, including food packaging, non-stick pots and pans, water and stain repellent clothing, etc. Due to their water solubility and persistent nature, they can end up in groundwater and require treatment. The contamination has been identified off the base and impacted a bore that is used to blend with the Katherine Town Water supply.
The Australian Department of Defence (Defence) contracted ECT to tackle this difficult project because of its proven ion exchange resin technology and experience delivering turnkey, modular solutions to address similar PFAS challenges. ECT provided a 200-gpm (3.2 L/sec) system that could consistently meet the project objective to produce treated water with PFAS concentrations to non-detect (i.e., less than the limit of reporting).
ECT’s PFAS-removal system, a supplement to the existing drinking water treatment plant in Katherine, included pretreatment filtration to remove solids, and specialized ion exchange resin for PFAS removal. ECT installed the system in international shipping containers, which allowed for easier transportation from the U.S. to Australia, and rapid, “plug and play” onsite readiness. By manufacturing the system in ECT’s central fabrication shop, ECT’s engineers worked directly with structural, mechanical, electrical and instrumentation trades to ensure quality, efficient construction. This also facilitated operational debugging prior to shipment and translated to faster onsite readiness. ECT worked cooperatively with Defence and the Northern Territory Power and Water Corporation to efficiently install and start up the PFAS-removal system once it was in Australia.
Defence accelerated the delivery schedule by five weeks by air-freighting the system from Maine in the U.S. to Darwin, Australia in an Antonov An-124 transport plane. The entire design, fabrication, shipping and installation process took less than four months. The system went online in late October 2017 and is meeting all project objectives, including non-detect effluent for all 28 PFAS compounds.