The Department of Defense’s (DoD’s) goal to use per- and polyfluoroalkyl substance (PFAS)-free firefighting formulations requires that existing firefighting systems that have previously contained PFAS-based agents be cleaned prior to use with PFAS-free formulations. With a large amount of foam delivery systems in aircraft hangars and on firefighting vehicles, replacing or cleaning this equipment would be very costly. Development of a method to remove all trace elements of the current firefighting agent from its existing systems, thereby eliminating the need to replace equipment, would be a substantial cost savings for the DoD.
In 2020, ESTCP began funding a group of projects that will demonstrate and validate environmentally sustainable methods for cleaning firefighting delivery systems in aircraft hangars or on firefighting vehicles as well as any rinsate or residue derived from the cleaning process. Described below are the six projects that were selected for funding.
- At Duke University, Dr. Marc Deshusses and his team will demonstrate the use of supercritical water oxidation (SCWO) for the complete destruction of PFAS in a variety of relevant waste streams. The PFAS destruction efficacy will be quantified and optimized under a range of operating conditions. The results of this demonstration will provide a cost-effective, scalable treatment option that has the ability to co-treat all types of wastes. (Project Overview)
- Dr. Selma Mededovic at DMAX Plasma, LLC and her team will demonstrate the operation of a mobile plasma treatment system for the treatment of AFFF rinsate from firefighting delivery systems. This technology does not need chemical additions and produces no residual waste that will limit future liability. (Project Overview)
- At Colorado School of Mines, Dr. Chris Bellona and his team will demonstrate the use of propylene glycol as a co-solvent to remove residual AFFF constituents from tanks and lines of firefighting delivery systems. In addition, they will optimize a nanofiltration process for separating the PFAS and co-solvent mixtures. This demonstration will provide a cost-effective approach for cleaning out older firefighting equipment for use with new, PFAS-free firefighting agents. (Project Overview)
- Mr. Ian Ross from Arcadis and his team will demonstrate the use of a biodegradable cleaning reagent as an effective cleaning option to remove entrained PFAS from fire suppression systems and associated infrastructure. The results of this demonstration will provide an optimized, standardized cleaning method to remove PFAS from existing infrastructure across DoD. (Project Overview)
- At CDM Smith, Inc., Dr. Kent Sorenson and his project team will demonstrate the use of the treatment solution, PerfluorAd®, as a functional precipitate to enhance the cleanout of firefighting delivery systems and the resulting rinsate. This demonstration will provide a low-cost, sustainable process for cleaning firefighting delivery systems with little waste production. (Project Overview)
- Dr. Matthew Magnuson from the U.S. Environmental Protection Agency (USEPA) and his team will provide data, information, and best practices on the efficacies of decontamination techniques for firefighting systems and how to manage the decontamination solutions containing PFAS. The project results will include a standardized decontamination framework based on a toolbox of options utilized across the DoD aviation firefighting community. (Project Overview)
Summaries of these demonstration projects are available on the SERDP and ESTCP website and all reports originating from these efforts will be available from the project webpages.
