What to do with vast stockpiles of PFAS-laden firefighting foam?

Millions of litres of firefighting foam that contain high levels of per- and polyfluoroalkyl substances (PFAS) are sitting in stockpiles. Much of this leftover material has been there for decades, held in storage at fire stations, airports, oil facilities and chemical manufacturing plants in the US. Until now, there hasn’t been an acceptable method to rid the world of these stashes of aqueous film-forming foams (AFFF), but the Us-based R&D organisation Battelle is set to tackle this.

The non-profit has proven that its new technology based on supercritical water oxidation – affectionately dubbed the PFAS Annihilator – completely destroyed stores of PFAS-laden AFFF in a recent deployment that was funded by Greenfire, a US firefighting products company. By forming a thin film that coats the fuel and starves fire of oxygen, these foams that have been used for decades are remarkably good at suppressing diesel, propane, petrol and jet fuel fires.

In the past, runoff from AFFF was not contained during firefighting training sessions or when extinguishing actual fires, allowing the PFAS chemicals that do not degrade in the environment to leach into soil and groundwater. Now, recent government regulations involving PFAS mean that many of the military sites, fire training centres and airports that have relied on AFFF for more than 50 years have been directed to stop using these products, and stockpiles have built up.