While industry waits for cost-effective complete destruction technologies for soil and groundwater contamination by PFAS compounds (the “forever chemicals” that have become one of the critical emerging environmental contaminant issues of recent times), site owners are driven to risk management approaches, preventing the further migration of existing impacts. In October of 2023, in Northern Alberta, a world-first injection of a specifically-engineered PFAS sorption media based on modified clay was successfully carried out to block migration of relatively high concentrations of PFAS compounds in groundwater along a preferential pathway with major access/infrastructure issues. This talk explains the technique, details the lessons learned – and as a special bonus for GeoEnviroPro – presents the latest available data on long-term performance.