Geosynthetic Barriers for PFAS containment: current options, historical precedents and new materials

Abstract

Every modern landfill, containment facility and construction and infrastructure site utilizes geosynthetic materials across a broad range of applications. The relatively recently identified need to contain sites and materials containing and contaminated with Per- and polyfluoroalkyl substances (PFASs) has caused increasing interest, research and materials development in the geosynthetics field. How well will the existing materials contain PFASs? Are the technical specifications and material compositions that have worked for similar applications in the past suitable for PFASs or are new materials necessary? This presents an overview of what is in the “solution toolbox” today and the best available options. The economics and realistic performance levels are also presented as a contribution to the ongoing discussion of appropriate regulatory requirements. This presentation includes references for the testing of both geomembrane (thick plastic sheet, and GCL (Geosynthetic Clay Liners) and “GCL-similar” materials specific to PFAS containment. The permeation rates, adsorption rates, effectiveness at retaining absorbed PFAS materials are compared, both as a comparison to similar past performance and as estimates of what can be expected in the future for newly developed materials. These materials have a broad and impressive track record as civil engineering barriers, however, even with the best practices and materials, some of the proposed regulatory requirements may not be attainable, and certainly not without significant expense.