“Remediation of AFFF-Impacted Fire Suppression Systems Using Conventional and Closed-Circuit Desalination Nanofiltration” by Dr. Christopher Bellona (ESTCP Project ER20-5369) 

The objectives of ER20-5369 were to (1) develop and evaluate a rinsing procedure for removal of PFAS from AFFF delivery equipment, and (2) evaluate the use of a closed-circuit high-pressure nanofiltration/reverse osmosis (CCNF/RO) system for the concentration and treatment of AFFF residuals. An AFFF delivery pipe was obtained and employed in lab-scale rinsing experiments designed to evaluate rinsing chemistries and the desorption of PFAS. Pilot-scale experiments with a CCNF/RO system were used to select a candidate membrane for demonstration testing and evaluate the impact of operating conditions on PFAS separation and concentration. Clean-out of a firetruck was subsequently performed at Tyndall Air Force Base to evaluate both the developed rinsing procedure and the treatment and concentration of AFFF rinsing residuals. This presentation will provide an overview of the use of RO and NF for PFAS separations and residual concentrations, challenges in removing residual PFAS from AFFF delivery equipment, and results and lessons learned from the demonstration firetruck cleanout. 

“Demonstration and Validation of Environmentally Sustainable Methods to Effectively Remove PFAS from Fire Suppression Systems” by Dr. Johnsie Lang (ESTCP Project ER20-5364) 

The overall objective of this project was to develop methods for effectively removing entrained PFAS from existing fire suppression infrastructure, including characterization tools for examining PFAS impacted surfaces. Fire suppression systems, such as fixed hangar systems and aviation rescue and firefighting (ARFF) vehicles, are known to be impacted by residual PFAS absorbed to internal surfaces as a result of the legacy and ongoing use of Class B firefighting foams, such as AFFF. When fire suppression systems are transitioned to fluorine free foam (F3) without appropriate cleaning, residual PFAS have been shown to contaminate the replacement F3. For DoD to reduce PFAS liability, a field-proven protocol is required to remove PFAS entrained on surfaces to prevent contamination of new foams. This presentation will discuss the methods developed. First, laboratory work was conducted to evaluate PFAS residuals on hangar piping exposed to AFFF for a prolonged period, as well as optimize removal methods. Next, optimized cleaning methods were demonstrated in the field on an ARFF vehicle and a fixed fire suppression system. These methods will provide a basis for wider application at DoD facilities and other sites. 

Dr. Christopher Bellona is an associate professor in the Department of Civil and Environmental Engineering at the Colorado School of Mines in Golden, Colorado. His area of expertise is the removal of contaminants by physico-chemical treatment processes for many applications, including water and wastewater treatment, potable water reuse and remediation. His recent research projects have been funded by the DoD, USEPA, Bureau of Reclamation, National Science Foundation, Water Research Foundation and private industry. Dr. Bellona has served as the primary investigator (PI) or co-PI of various research projects evaluating technologies for the removal of PFAS, including adsorbents (activated carbon, ion-exchange, novel materials), membranes (nanofiltration and reverse osmosis), and destructive methods (plasma, UV-based reductive processes). He has published more than 45 peer-reviewed publications and presented his research at numerous national and international conferences. Dr. Bellona has a bachelor’s degree in environmental science from Western Washington University and master’s and doctoral degrees in environmental science and engineering from the Colorado School of Mines. 

Dr. Johnsie Lang serves as a technical expert at Arcadis in Raleigh, North Carolina. Her primary research areas include solid waste, PFAS and harmful algal blooms (HABs). She has authored over a dozen peer-reviewed publications and participated in research funded by ESTCP, National Science Foundation, the Air Force Civil Engineer Center (AFCEC), Hinkley Center for Solid and Hazardous Waste Management and various industrial sponsors. Her Oak Ridge Institute for Science and Education (ORISE) postdoctoral fellowship at USEPA resulted in a deep understanding of various analytical methods used to measure emerging contaminants in the environment. Recently, Dr. Lang has focused her efforts on developing a method for removing residual PFAS from fire suppression systems during foam transition. In addition, she serves as a technical advisor for several site investigations on PFAS at US Army installations and assists various industrial and commercial clients with understanding PFAS impacts at their facilities. Dr. Lang received her bachelor’s and master’s degrees in environmental health engineering and her doctoral degree in civil engineering from North Carolina State University.