More than two billion litres of PFAS (Per- and polyfluoroalkyl substances) contaminated groundwater has been treated by Enviropacific in the past nine years. And that’s just skimming the surface of the amount of contamination throughout Australia, according to Sagar Adhikari.
The General Manager of Enviropacific’s water division says the specialist environmental service has refined an effective treatment process since it began treating PFAS-contaminated water in 2013 and consistently achieves water quality well below discharge criteria.
However, a commitment to preventing, stopping, and reversing environmental damage means the company continues to look for advanced treatment methods.
Sagar says Enviropacific’s subsidiary company Membrane Systems Australia, in partnership with the University of South Australia, has patented technology that will change the way PFAS-contaminated water is treated.
“This technology does full destruction of PFAS on site,” he says. “It strips PFAS from contaminated water and the resultant by-product. It’s a huge advantage compared to what’s been done in the past.”
PFAS have been used in a variety of applications over time. Because they don’t fully break down naturally, they persist in low levels almost everywhere in the environment, according to the Australian Government PFAS Taskforce website. It states that increased levels of PFAS can be found near sewage treatment plants, landfills, and places where fire-fighting foams have been used, including mining operations, fuel refineries, airports, and fire-training grounds.
The taskforce was set up in 2016 to guide the government’s response to rising concerns about PFAS and related health issues. The Department of Defence has its own PFAS Investigation and Management Program which, as of January 2022, had spent $540.2 million in the past six years on PFAS remediation. State and territory governments throughout Australia are also conducting their own investigations into contamination.
Sagar says Enviropacific is working to remediate many defence sites of legacy PFAS. The treatment includes conducting groundwater sampling and testing to determine not just the PFAS contamination but other water pollutants including total suspended solids, hydrocarbons, and ammonia.
He says the company’s intellectual property has developed over the past 10 years, with lessons learned from each project allowing site specific treatment plants to be designed by Enviropacific engineers.
While the use of activated carbon and ion exchange is a proven method to remove PFAS from water, Sagar says the process produces a contaminated by-product that is either transferred to landfill or destroyed using thermal desorption.
He describes it as contaminated water being fed into a “black box”, which contains PFAS absorption medium. The water at the end of the treatment is clean but the PFAS is stored in the bed and over time it becomes saturated and is thrown away.
Membrane Systems Australia technology uses a process to strip the PFAS absorption medium of PFAS so the absorption medium can be reused. The concentrated PFAS goes through another process which breaks the carbon-fluorine bond in PFAS, and the products of destruction will be fluoride and carbon dioxide with minimal waste.
While the technology doesn’t completely end the need to replace the bed, at some point it will no longer be able to be regenerated, Sagar says it is minimising the volume of waste that goes off site.
He says the technology has been in development for several years and was recently successfully applied at what is believed to be one of Australia’s biggest PFAS remediation projects.
“The patented technology within the PFAS removal system currently treats up to 2ML/day of contaminated ground water and successfully removes greater than 99 per cent of both short and long chain PFAS precursors in a single pass,” he says.
“Undetected levels are being achieved once the water has passed through its polishing stage.”
He says the project consists of a feed tank, two containerised patented technology pods and a filtrate tank on a relatively small footprint. The system can be scaled to treat from 100kl/day to 2ML/day while still removing more than 99 per cent of PFAS contaminants.
The system can also be used to remove other contaminants including trichloroethene (TCE), pesticides, herbicides, and hydrocarbons.
Sagar says the resultant water is suitable for irrigation or use as potable water subject to local approvals.
“We’re the only ones using this technology,” he says. “Most conventional technologies are batch process that aren’t physically capable of treating large volumes of water. Our system is a continuous process, is completely sustainable and it’s available now.”
For more information, visit: www.enviropacific.com.au