Interaction between PFASs and geosynthetic liners: current status and the way forward

This paper gives an overview of the current state of the practice on the interaction between geosynthetic liners and per- and polyfluoroalkyl substances (PFASs). The importance of PFAS chemistry and the need to make a clear distinction between on-site repositories and landfill applications is highlighted, as the liners will be subjected to widely different concentration loadings and types of dominating PFASs. Consequently, the selection of geosynthetic liner components needs to account for these differences and distinguish between the expected exposure conditions. In particular, geomembranes need to be selected carefully as their resin type will dictate their performance. Preliminary hydraulic conductivity test results using unamended and activated carbon amended geosynthetic clay liners indicate they can play a role in minimising the migration of PFAS, although the tests are still ongoing.