Closed-Loop Thermochemical Destruction of PFAS for Water and Land Systems at Prairie Island Indian Community

Testing Lasting PFAS Solutions

PFAS are long-lasting compounds with strong carbon-fluorine bonds, making them resistant to breaking down in the environment. In Minnesota, PFAS have been detected in groundwater and private wells, particularly in shallow sand and gravel aquifers influenced by historical industrial releases.

Within the Prairie Island Indian Community’s land management context, PFAS circulates in a land-water-vegetation cycle, rather than remaining confined to drinking water. Peer-reviewed studies document PFAS uptake into plant tissues when irrigated with contaminated water or grown on impacted soils. Biomass harvesting (traditional foods and medicines for Tribal resident use, buffalo grazing, etc.) therefore function as a concentration step rather than a destructive one. Similarly, PIIC’s controlled prairie burn practices do not maintain the controlled temperature and residence time required for verified defluorination and can redistribute fluorinated compounds into smoke or ash. Without a strategy for permanent breakdown of PFAS, removal methods risk redistributing it across the environment rather than eliminating it entirely.

The research will test a closed-loop treatment strategy that combines PFAS concentration from water and plant materials with catalytic microwave-assisted pyrolysis and fluorine mass-balance verification. If successful, the work will provide decision-ready scientific evidence to help PIIC and other Minnesota communities evaluate remediation approaches that eliminate, rather than merely transfer, PFAS.

Project Goals

• Create a verification-grade dataset documenting fluorine partitioning during thermochemical treatment of PFAS-laden sorbent and plant-derived matrices informed by field conditions at PIIC
• Develop a set of clearly articulated feasibility benchmarks that define what constitutes defensible thermochemical mineralization in PIIC’s land-based contexts
• Co-develop a technical briefing for PIIC Land and Environment staff and other leadership, shared in the context of their existing land stewardship, soil health, vegetation management and fire practices