A comprehensive study on the In-Situ Remediation of PFAS-Impacted Groundwater (Permeable Reactive Barriers (PRBs) Coupled with Treatment-Train Pilots and Long-Term Performance Modelling)

Per- and polyfluoroalkyl substances (PFAS), commonly termed forever chemicals, pose a persistent threat to groundwater systems due to their extreme chemical stability, high mobility, and resistance to conventional remediation technologies. Ex-situ treatment approaches, while effective in controlled environments, are often cost-intensive, energy-demanding, and impractical for large contaminated aquifers. This research paper proposes an innovative composite framework for in-situ remediation of PFAS-impacted groundwater using Permeable Reactive Barriers (PRBs) integrated with treatment-train pilot systems and long-term performance modelling. The study emphasizes interception-based containment, synergistic removal and destruction mechanisms, and predictive longevity analysis through breakthrough curves and media regeneration modelling. Special attention is given to mixedcontaminant scenarios, where PFAS coexist with persistent organic pollutants (POPs), solvents, and inorganic co-contaminants. The proposed framework advances sustainable groundwater remediation by combining engineering feasibility, environmental safety, and policy relevance.