Per- and polyfluoroalkyl substances, collectively known as PFAS, have contaminated sites across Australia wherever firefighting foam was used extensively. The chemicals don’t break down naturally, accumulate in organisms, and persist in groundwater for decades. Australian researchers are testing methods to degrade PFAS or sequester it safely, with some techniques showing promise in controlled conditions.

The Contamination Legacy

PFAS contamination clusters around RAAF bases, civilian airports, and industrial sites where aqueous film-forming foam (AFFF) was used for fire suppression. Williamtown, Katherine, Oakey, and dozens of other sites face ongoing contamination affecting surrounding communities and agriculture.

The chemicals’ stability—the very property that made them useful for firefighting—makes environmental cleanup extraordinarily difficult. PFAS molecules contain carbon-fluorine bonds, among the strongest in chemistry. Breaking these bonds requires significant energy or specialised catalysts.

Traditional remediation approaches like bioremediation don’t work; microorganisms can’t metabolise PFAS. Excavation and disposal simply moves the problem elsewhere. Effective solutions must destroy PFAS molecules or permanently immobilise them.

Electrochemical Degradation Tests

Researchers at RMIT University are testing electrochemical methods that apply electrical current to contaminated water, breaking down PFAS molecules into simpler, less harmful compounds. Laboratory results show near-complete degradation of several PFAS variants within hours under optimised conditions.

The technology works by generating reactive species—free radicals and other highly reactive molecules—that attack PFAS molecules’ carbon-fluorine bonds. Unlike thermal destruction methods that require high temperatures, electrochemical approaches operate near room temperature, reducing energy demands.

Scaling from laboratory benchtop to field applications presents challenges. The electrochemical cells require careful design to maintain efficiency with real contaminated water containing various dissolved substances. Electrode materials degrade over time and need replacement. Capital and operating costs for treating large volumes remain uncertain.

Photocatalytic Approaches

University of Queensland researchers are investigating photocatalysis—using light and catalyst materials to break down PFAS. The approach uses titanium dioxide or similar materials that, when illuminated with UV light, generate reactive oxygen species that attack contaminants.

Initial results demonstrate PFAS degradation rates comparable to electrochemical methods. The advantage is simpler equipment with fewer moving parts. Disadvantages include the need for UV light sources and slower reaction rates in turbid water where light penetration is limited.

Field trials at a former RAAF base have begun, treating contaminated groundwater pumped through a reactor vessel containing photocatalyst particles under UV illumination. The system operates continuously, treating several thousand litres daily. Results over the coming months will indicate whether laboratory performance translates to practical remediation.

Activated Carbon and Sequestration

When degradation isn’t feasible, sequestration offers an alternative. Activated carbon and ion exchange resins can adsorb PFAS from water, concentrating it for disposal or further treatment. This doesn’t destroy PFAS but removes it from drinking water and prevents environmental spread.

Several contaminated sites already use this approach for water treatment. The technology is mature and reliable. The challenge is managing spent carbon or resins containing concentrated PFAS. Current practice involves incineration at high temperatures, which is expensive and has its own environmental considerations.

Researchers at Monash University are developing materials that bind PFAS more selectively and with greater capacity than standard activated carbon. Their experimental resins show promising performance, but manufacturing costs need reduction before commercial viability. Still, incremental improvements in adsorption efficiency could substantially reduce treatment costs.

Bioremediation Research Continues

Despite conventional wisdom that microorganisms can’t degrade PFAS, some researchers haven’t given up. Macquarie University scientists are investigating bacterial strains that show limited ability to break down certain PFAS compounds under specific conditions.

The degradation rates are extremely slow—weeks to months rather than hours—and only affect particular PFAS variants. But any biological pathway represents potential for optimisation through genetic engineering or selective breeding of bacterial strains. This remains speculative, but the potential payoff of a low-energy biological remediation method justifies continued investigation.

Thermal Treatment Methods

High-temperature incineration destroys PFAS effectively but requires temperatures above 1,000°C and sophisticated scrubbing systems to prevent fluoride gas emissions. Portable incineration units have treated contaminated soil at some sites, but costs are prohibitive for large-scale groundwater or soil remediation.

Alternative thermal methods under investigation include supercritical water oxidation and plasma treatment. Both can break down PFAS at lower temperatures than incineration, potentially reducing costs. Pilot facilities are testing these approaches, but operational data remains limited.

The Regulatory Environment

Australian drinking water guidelines for PFAS have tightened as health research reveals lower safe exposure levels. This increases the number of sites requiring remediation and raises treatment standards. Technologies that achieved acceptable results three years ago may no longer meet current guidelines.

Defence Department sites face particular scrutiny given their responsibility for much of the contamination. Funding for research and remediation at Defence sites has increased, though community groups argue it remains inadequate given the problem’s scale. Legal settlements with affected communities have exceeded $200 million to date, with more claims pending.

Progress Toward Practical Solutions

None of the technologies under development offer cheap, quick fixes. PFAS remediation will remain expensive and slow regardless of technical advances. But research is progressively identifying methods that work under field conditions, not just in laboratories.

The most promising near-term applications combine approaches: using adsorption to concentrate PFAS from large water volumes, then applying degradation techniques to smaller volumes of concentrated contaminant. This reduces the volume requiring expensive treatment while still destroying PFAS rather than just relocating it.

Site-specific conditions strongly influence which techniques work best. Groundwater chemistry, contaminant concentrations, soil types, and regulatory requirements all affect technology selection. Australia’s research efforts are generating a toolkit of approaches rather than a single solution, which matches the problem’s diversity.

What Communities Can Expect

Affected communities want timelines and assurances. Researchers struggle to provide these honestly. Current remediation efforts will take decades, not years. Technologies improving today will help, but PFAS contamination will outlast political terms and funding cycles.

The more optimistic scenario involves proven remediation techniques reducing contamination to acceptable levels at high-priority sites—drinking water sources, agricultural areas, residential communities—within a decade. Complete remediation of all contaminated sites is unrealistic given current technology and available funding.

Research continues on prevention strategies too. PFAS-free firefighting foams exist and are gradually replacing AFFF where required. This prevents new contamination but doesn’t address existing legacy pollution.

Australian PFAS research has achieved modest successes: laboratory techniques that work, pilot programs demonstrating field applicability, and growing understanding of how different PFAS compounds behave in Australian soils and groundwater. Translating this into large-scale cleanup remains the challenge ahead.