Darwin’s world-first PFAS and leachate treatment plant reaches a milestone
10 November, 2023
It has been one year since the Water & Carbon Group (WCG) officially commissioned the $13 million Shoal Bay Leachate Treatment Plant for the City of Darwin. The plant uses WCG’s patented LEEF (Low Energy Evaporative Fractionation) System® to remove per- and poly-fluoroalkyl substances (PFAS) and is believed to be the first permanent facility treating PFAS in leachate, coupled with biological and ecological treatment.
The facility has been a breakthrough in the removal of toxic PFAS synthetic chemicals, using an approach that is one-of-a-kind, and a remarkable success in removing the so-called ‘forever chemicals’.
The Shoal Bay Waste Management Facility receives more than 180,000 tonnes of waste each year from 164,000 residents who live in the greater Darwin region. Due to the region’s high rainfall, the facility also generates large volumes of leachate that must be treated and kept out of the surrounding environment, which includes ecologically important habitat.
After being awarded the contract by City of Darwin, WCG designed and engineered the LEEF System® after finding there was nothing ‘off-the-shelf’ that was feasible. The patented process uses foam-fractionation to remove PFAS from the leachate. Since its commissioning, the plant has exceeded expectations and is setting a new standard for efficient and feasible solutions to PFAS contamination, reducing PFAS to extremely low levels, and taking the ‘forever’ out of forever chemicals.
David Leinster, WCG’s Wastewater & Solutions Development Manager, said in full production the plant was processing up to 140,000 litres of leachate each day.
“What sets this plant apart is its ability to produce a very small, PFAS enriched waste stream without the use of chemical additives. It operates with low energy and operational requirements and eliminates the need for costly pre-treatment. This contrasts with more conventional methods like reverse osmosis, which tend to be more costly,” said David.
“In addition to removing PFAS, the plant integrates biological and ecological treatment processes in a closed loop system. We’re seeing some phenomenal results with regulatory requirements not only being met but exceeded,” he said.
Lord Mayor Kon Vatskalis said City of Darwin’s treatment plant at Shoal Bay Waste Management Facility sets a new Australian standard for dealing with leachate.
“City of Darwin is leading the country with this technology, and I am proud that the Shoal Bay Waste Management Facility features an Australian-first approach in reducing the threat of PFAS.
“Leachate and PFAS are problems faced by all Australian waste management facilities, and we now have a solution that protects our environment and meets the requirements of the Northern Territory Environment Protection Authority,” Mr Vatskalis said.
Nick Fewster, Executive Manager of Environment and Waste Services at City of Darwin emphasized the importance of addressing leachate and PFAS concerns in waste management facilities.
“Leachate, and PFAS within leachate, is an issue for all waste management facilities. Our commitment at the City of Darwin was to tackle these contaminants using an innovative approach to protect the local environment and the community.
“Investment in this innovative leachate and LEEF System PFAS treatment technology has enabled City of Darwin to treat large volumes of leachate generated in a high rainfall environment. We’re proud to say that this achievement positions Darwin as a global leader in leachate and PFAS treatment,” said Nick.
Jim Hunter, CEO of the Water & Carbon Group, said the leachate treatment plant and the LEEF System® had achieved, if not exceeded, all project targets and had reduced operational costs to below budget.
“It’s an extremely efficient and effective solution in addressing the City of Darwin’s leachate challenges,” Mr Hunter said.
“It’s a great result and I couldn’t be prouder of our team who designed, constructed and continue to operate the system on a daily basis to ensure it delivers the best results.”
The future for LEEF is going global with the Water & Carbon Group set to commission its first operational LEEF System® in the US in early 2024 with US waste giant Waste Connections at their Bethlehem Landfill in Pennsylvania.