Principal Environmental Scientist
Dr. Toase is a Principal Environmental Scientist at Ventia where manages R&D and provides technical advice on complex remediation projects. Prior to working at Ventia, she worked for the NSW EPA as their Principal Technical Advisor. She completed a PhD in Geochemistry in 2015 at Macquarie University, Sydney.
PRACTITIONER WORKSHOP PANELIST
PRACTITIONER WORKSHOP #1: Advances in Treatment of PFAS-Impacted Environmental Media
Immobilization of PFAS impacted soil: the chemistry of immobilization, analytical challenges and key performance indicators for long-term performance
Per- and poly-fluoroalkyl substances (PFAS) are synthetically produced highly-fluorinated organic compounds. PFAS are lipid and water repellent, highly stable and are effective surface-active agents in high temperature environments. These unique physio-chemical characteristics account for their widespread use in Aqueous Film Forming Foams (AFFF), household products, semiconductors, hydraulic fluids, photolithography and the textiles industry.
Legacy PFAS contamination exists in soil, sediment, biota and surface and ground water. However, PFAS have also been detected in landfill leachate, wastewater and sewerage sludge. PFAS are highly mobile, resistant to environmental degradation and have been shown to bioaccumulate in the ecosystem. As PFAS are naturally resistant to degradation by hydrolysis, biotransformation and abiotic reduction, the management of waste and soil contaminated with PFAS is highly challenging.
The majority of remediation technologies applicable to PFAS remain in developmental stages, however immobilization techniques have emerged as a popular treatment technique in the USA and Australia.
This presentation provides a background on the chemistry of immobilization and presents some of the challenges associated with immobilising PFAS impacted soil and waste. Analytical challenges, mechanisms for re-solubilisation and key performance indicators for long-term immobilization efficacy are also discussed.