A guidance document was created for Transport Canada (TC) personnel and their environmental consultants and contractors to assist with decision-making in the management of TC per- and polyfluoroalkyl substances (PFAS)-impacted wastes. The key objectives of the guidance as drafted included:

1. A description of applicable legislation/policies and regulatory requirements as they relate to management of PFAS wastes from federal operations in Canada;
2. Waste management options for solid and liquid PFAS waste, including information on landfills and incinerators in Canada; and,
3. Development of a best-practices framework that can be used to guide decision-making regarding the management of PFAS wastes.

Background/Objectives. Loss of a concentrated aqueous film-forming foam resulted in per- and polyfluoroalkyl substances (PFAS) impact to infrastructure and nearby surface water. The infrastructure included a domestic/industrial sewer system and a stormwater system which service numerous industrial facilities. The sewer and stormwater systems were subsequently isolated to prevent further impact to the environment.

The sewer and stormwater systems were washed out sequentially using water flushes, sodium hydroxide and a specially formulated alcohol-based biodegradable solvent.

Approximately 6 million liters (ML) of wastewater and 6 ML of stormwater were collected and contained in 20m3 capacity tanks (isotainers), including the waste from the washing the sewer/stormwater systems. The objective of the project was to treat collected water to a concentration of less than 0.25 μg/L Sum of PFAS (28 compounds) as measured by total oxidizable precursor (TOP) assay. The project is the first example of use of ozofractionation for PFAS and for performance of a remediation system to be validated using TOP assay.

Approach/Activities. The combination of high organic load and PFAS from the foam concentrate in the collected waters and waste created a complex treatment challenge. Each isotainer contained a differing spectrum of organics, inorganics and variable PFAS concentrations. Isotainers containing the wash water from cleaning the sewer and stormwater systems with the caustic and solvent were also treated. Two companies teamed up to design and install an innovative ozofractionation treatment process. Ozofractionation utilizes ozone to create a stream of bubbles that separate and concentrate PFAS in a foam fraction that is created at the top of a series of vessels and separated as a PFAS concentrate. The high surface area created by ozone micro-nano bubbles allowed effective removal of PFAS to the foam fraction. The ozone provided the oxidative capacity to break down the organic load of the sewage. The process also efficiently handled and separated suspended solids. The primary waste generated from the process is a highly concentrated aqueous PFAS stream. The system was designed for a treatment capacity of 5,000 L/hr, and, given the urgent nature of the application, a full-scale system, was designed, installed and commissioned in four weeks.

Results/Lessons Learned. The ozofractionation process demonstrated the ability to treat high PFAS concentrations up to 4,000 ug/L as well as much lower PFAS concentrations whilst also handling the high organic load and other co-contaminants of the mixture of raw domestic and industrial sewage. A reduction of greater than 99.9% as measured by sum of PFAS (28), TOP assay, was routinely achieved. The system reliably removed long-chain and short-chain PFAS down below 2 μg/L. To reach the final treatment objective, a membrane filtration system was installed to reduce concentrations reliably below 0.25 μg/L TOP assay.

Ian Ross, Senior Technical Director and Global, In Situ Remediation Technical Lead/Global PFAS Lead, Arcadis UK Ian Ross, Ph.D., is a Senior Technical Director and Global, In Situ Remediation Technical Lead/Global PFAS Lead at Arcadis from Leeds, West Yorkshire, UK.

His focus for the last four years has been on solely on PFAS after initially working on options for perfluorooctane sulfonate (PFOS) management in 2005 after the Buncefield Fire in the UK. He has was part of the team authoring and reviewing the CONCAWE PFAS guidance document and has published several articles on PFAS analysis, site investigation and remediation, including a recent book chapter on PFASs management.

He has been focussed on the bioremediation of xenobiotics for over 26 years as a result of three applied industrially sponsored academic research projects. At Arcadis he has worked designing and implementing innovative chemical, physical and biological remediation technologies.

He has evaluated the fate and transport, biodegradation potential and treatment options for contaminants including hydrocarbons, chlorinated solvents, nitroaromatics, PFAS, lindane (hexachlorocyclohexane), polychlorinated biphneyls (PCBs), Aldrin, Dieldrin and dichlorodiphenyltrichloroethane (DDT).

He has experience with multiple physical, chemical and biological treatment technologies and has won several national and international remediation awards for designing their application.

A turnkey, modular, ion exchange resin system was provided to treat per- and polyfluoroalkyl substances (PFAS)-contaminated, investigation-derived waste (IDW) that also contained part per million (ppm)‐levels of petroleum, oil, and lubricants (POLs); chlorinated solvents; and, dissolved metals. The system was designed to process 10,000-gallon batches at Eielson Air Force Base in Fairbanks, Alaska. Unit operations include sorbent media for free product removal, back-washable granular activated carbon (GAC) filtration, ion exchange to remove iron and other fouling agents, and two types of specialized ion exchange resins for PFAS removal.

The system was installed in an international shipping container for ease of transport, and started treating water in October 2017. This presentation will describe the design, installation, start-up, operation, and lessons learned, and will review the first several months of operating data. This effective mobile system design could be “standardized” to serve as a tool for managing PFAS-bearing IDW at military bases around the world.

Dale Wynkoop, Global Director of Sales and Applications, Emerging Compounds Treatment Technologies
Dale Wynkoop is the Global Director of Sales and Applications of ECT2 (Emerging Compounds Treatment Technologies). ECT2 is an equipment company focused on developing and commercializing treatment technologies for emerging, difficult-to-treat contaminants. Dale’s responsibilities include: business development, marketing and new product development.

Dale has been in the water treatment industry since 1993 and joined ECT2 in 2017 to lead the commercialization of ECT2’s synthetic media technologies for the sustainable treatment of PFAS, 1,4-dioxane, and other emerging contaminants. He received his B.S. in Mechanical Engineering from The Ohio State University in 1988.