Southwest Regional Sales Manager
Mr. Perlow has spent the last two years living in Australia installing, starting up and operating the world’s first PFAS remediation system utilizing regenerable ion exchange resin. While in Australia he participated in building 9 PFAS remediation systems. Since returning to the United States, he was been working to help educate and evaluate sites for clients with PFAS impacts. Prior to living in Australia, Jim worked as professional environmental engineer and professional geologist for 18 years in the environmental consultant and wastewater sectors.
Innovative Waste Minimisation During PFAS Contaminated Water Remediation
INTRODUCTION: As part of its response to per- and poly-fluoroalkyl substances (PFAS) contamination resulting from the historical uses of aqueous film forming foam (AFFF), the Australian Department of Defence (Defence) completed a detailed environmental site investigation of an area of over 150 square kilometres, incorporating RAAF Base Tindal and private land in the vicinity of the Defence property. The investigation identified that PFAS contamination had entered groundwater and migrated offsite towards the Katherine River. RAAF Base Tindal is located in the Northern Territory, approximately 17 kilometres from Katherine and 330 kilometres from Darwin. The location of the property makes it critical that any equipment and consumables needed, or waste removed from the property, are carefully considered as it is logistically challenging to transport products to and from the property, particularly during the wet season. In addition, waste disposal and treatment facilities are limited in the NT.
APPROACH: ECT2 has installed a water treatment system at each of the two main groundwater source areas on the Tindal property; the Fire Training Area (FTA) and the Fire Station Area (FSA). The central regeneration system is located alongside the FTA water treatment system and serves both the FTA and the FSA. Contaminated groundwater is extracted from wells located within each of the plumes and is pumped to the two individual treatment systems. PFAS concentrations of up to 50ug/l are being treated at the Fire Station Area and up to 40ug/l at the FTA. Regenerable ion exchange (IX) resin is being used to remove PFAS compounds from the water using a lead/lag/polish treatment train arrangement.
RESULTS AND DISCUSSION: The FTA treatment system was commissioned in December 2018 and the FTS system was commissioned in March 2019. The use of multiple extraction wells has allowed contaminated water to be extracted from various combinations of wells, providing operators with the ability to maximise PFAS mass removal from the well network, thereby optimising the remediation efforts. Treated effluent quality has been consistent at both the FTA and FSA, consistently below the level of reporting (LOR) for all 28 PFAS compounds being monitored. The use of IX resin proven to have a high capacity for the removal of PFAS, combined with the unique resin regeneration technology, has resulted in the generation of minimal PFAS waste, while treating approximately 580,000 gallons of water per day. The lead/lag configuration of the resin vessels, multiple electronic failsafe features and remote monitoring capabilities has helped facilitate 98% uptime during 24/7 operations.
CONCLUSIONS: The application of innovative technology at RAAF Base Tindal has proven effective at consistently providing a very high level of PFAS removal, while minimizing PFAS waste generation to less than 1 gallon of waste per million gallons treated. This has helped avoid passing along the problem for future generations to resolve and has greatly diminished the reliance subsequent thermal desorption/destruction, which requires significant transportation and energy use.
What is Really in Aqueous Film Forming Foam and Does it Matter?
INTRODUCTION: Per- and polyfluoro¬alkyl substances (PFAS) contamination as a result of historical uses of aqueous film forming foam (AFFF) is a significant concern for military, aviation, fire authorities, bulk fuel storage owners and other similar entities. The primary triggers to manage PFAS contamination in water are perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonic acid (PFHxS) as these are the PFAS compounds most commonly found in legacy AFFFs that were used prior to the change in training, storage and use practices in the early to mid-2000s. These historical PFAS compounds have been replaced with shorter or longer chain compounds, or with modified structures, including ether linkages. These new compounds may result in unanticipated PFAS contamination, especially given that their toxicological impacts are not yet well understood. This is a concern particularly when managing waste water from current fire training activities, hangar foam tests or unintended releases and other similar activities.
APPROACH: As a result of requests to manage waste water from activities using a variety of foam products, ECT2 has undertaken laboratory research into the makeup of these foams to determine the PFAS compounds that can be identified, and the precursors which may degrade into PFAS of concern. The foam products were procured from manufacturers and mixed in accordance with their instructions for use; generally, 1%, 3% or 6%. The mix was then analysed using LC-MS-MS, with further dilution occurring to enable accurate analysis where necessary. The foam/water mix was also trialed in column testing using multiple ion exchange (IX) resins and granular activated carbons (GAC) to examine the ability of these treatment media to remove PFAS, including the shorter chains and precursor compounds.
RESULTS AND DISCUSSION: Initial analysis of foam concentrates identified a range of precursors which degrade to PFAS compounds of primary concern, as well as a number of long and short chain compounds which were not able to be identified. The columns tests demonstrated that the IX resin and GAC systems required for management of waste water from fire training activities, hangar foam tests and the like require EBCTs far in excess of those needed to manage the relatively dilute concentrations normally found in surface and ground water. These extended EBCTs point to the need for high-capacity absorbent media to reduce the need for treatment plants requiring large footprints and the associated high capital and O&M costs.
CONCLUSIONS: Caution is required when making assumptions about the content of the “newer” foams currently in use. It is not always accurate to assume that these foams do not include PFOS, PFHxS and PFOA, as active ingredients include compounds which may degrade into these compounds if not managed appropriately. Sustainable onsite treatment processes are available, and if appropriate research is conducted, will manage waste water from foam training activities in a manner which is effective, efficient and economical.