Per- and poly-fluoroalkyl substances (PFASs) are a complex and diverse group of highly-fluorinated organic contaminants. PFASs are lipid and water repellent, highly stable, and effective surface-active agents in high temperature environments. The legacy use of PFAS in aqueous film forming foams (AFFF) for firefighting has resulted in widespread environmental contamination at airports, fire training grounds, landfills, and manufacturing facilities. Perfluoralkyl acids (PFAAs), are a subgroup and include chemicals such as PFOS and PFOA that are bioaccumulative, persistent in the environment, and resistant to biodegradation. Polyfluoroalkyl substances can transform into stable PFAAs (i.e. terminal degradation products) during or after remediation. Polyfluoralkyl substances that may transform into PFAAs as referred to as PreFASs. The transformation of PreFASs has the potential to result in the recontamination of remediated soils with regulated PFAAs and jeopardise long-term remediation performance. The aim of this project is to optimise and validate the remediation of PFAS-contaminated soils using soil washing techniques and to assess and validate the sustainability and long-term performance of remediation.
The principal aim of this project is to better understand the fate and transport processes of PFASs in the soil environment in relation to the ex-situ soil washing and the immobilisation process for PFAS-contaminated soil remediation. There are four specific sub aims as below:
- To investigate the soil-water partitioning behaviour and the influence of chemical properties, soil properties, and solution pH on soil–water partitioning coefficients of PFASs,
- To assess the mobilization potential of a broad range of PFASs and PFAA precursors in AFFFs in water-saturated soil conditions for soil washing remediation,
- To assess the long-term leaching behaviour of PFASs in soil immobilized with selected commercial sorbents, and
- To study the transformation behaviour of AFFF-related PFAA zwitterionic precursors in the soil environment.
Research Outputs
Conference Abstracts
Nguyen, T.M.H., Bräunig, J., Thompson, K., Thompson, J., Kabiri, S., Navarro, D. A., Kookana, R. S., Grimison, C., Barnes, C. M., Higgins, C. P., McLaughlin, M. J., Mueller, J. F. Influences of Chemical Properties, Soil Properties, and Solution pH on Soil–Water Partitioning Coefficients of Per- and Polyfluoroalkyl Substances (PFASs). Soil Science Australia, Cairns, Australia, 27 June-2 July 2021.
Nguyen, T.M.H., Braunig, J., Thompson, K., Thompson, J., Kabiri, S., Navarro, D.A., Grimison, C., Barnes, C.M., Higgins, C.P., McLaughlin, M.J. & Mueller, J. Influences of Chemical Properties, Soil Properties, and Solution pH on Soil–Water Partitioning Coefficients of Per- and Polyfluoroalkyl Substances (PFASs), SETAC-AU Conference 2021, Melbourne, Australia, 30 August – 2 September 2021.
Nguyen, T.M.H., Bräunig, J., Kookana, R.S., Kaserzon, S.L., Knight, E.R., Vo, H.N.P., Kabiri, S., Navarro, D.A., Grimison, C., Riddell, N., Higgins, C.P., McLaughlin, M.J. and Mueller, J.F. Assessment of mobilization potential of per- and polyfluoroalkyl substances for soil remediation, Glasgow 22nd World Congress of Soil Science, 31 July-5 August 2022.
Nguyen, H.T.M., Bräunig, J., Barnes, C., Bowles, K. C., Mueller, J. F. Long-term Leaching Behavior of Perfluoroalkyl Acids in Soil Immobilized with Selected Prototype Sorbents. Ecoforum 2022, Newcastle, Australia, 8-10 August 2022.
Awards and Prizes
- 2020 American Chemistry Society Editor Choice Award for Influences of chemical properties, soil properties, and solution pH on soil-water partitioning coefficients of per- and polyfluoroalkyl substances (PFAS).
- 2021 QAEHS HDR Student Best Publication Awards, 3rd place for Influences of chemical properties, soil properties, and solution pH on soil-water partitioning coefficients of per- and polyfluoroalkyl substances (PFASs) in Environmental Science and Technology.
