PFAS Forensics: Best Practices for Unwinding Complex PFAS Sources

Michael Eberle, TRC presented Whose PFAS is it? Tips for Forensic Evaluations. Evaluation of the relative composition of individual PFAS compounds in surface water and groundwater samples can be an effective method to identify the source(s) of PFAS in these media. Comparison of chemical fingerprints in samples collected from surface water bodies and groundwater located downstream and downgradient of contaminated sites may appear to be the same simply because of the suite of analytes chosen for fingerprinting but fate and transport mechanisms (e.g., commingling, persistence, sorption, dilution) must be considered during source identification. PFAS fate and transport properties, including precursor transformation and sorption of PFAS to solids was examined in regard to the resulting fingerprints.
Matthew Dunn, TetraTech presented Precursor PFAS: A New Fluorinated Feedback Loop. Matt focused on methods and approaches that can help improve the efficacy of forensic approaches, including how the use of time weighted average data from passive samplers provides a broader and more representative set of data for forensics. Use of fate and transport models to understand pathways, distances, and fates of chemicals was discussed, and the importance of environmental meta data. Lastly, examples from published research displayed how environmental processes on small and large scales can impact source attribution studies.
Note: This webinar is presented for informational purposes. The views expressed do not necessarily reflect those of each of the NEWMOA-member states, and the strategies and technologies discussed should not be considered an endorsement by NEWMOA or its members.