Fluorosurfactants have been used effectively in firefighting foams since the 1960’s. However, increased concern by regulators and the public over the impact of per- and polyfluoroalkyl substances (PFAS) is changing the way firefighting foams are managed and regulated. Newly developed foams known as C6 foams, are proposed as ‘environmentally improved’ replacements, yet these replacements still contain significant amounts of short-chain PFAS, six perfluorinated carbons and less, that are currently regulated in several countries.

Foam users have been turning to fluorine free foams (F3) to maintain effective fire protection while better managing environmental liabilities, reputational risk and possible 3rd party litigation. The increased extinguishment performance of the new generation F3 have made them viable alternatives to fluorosurfactants for many applications and are currently in use as training foams, aviation applications in hangars and helipads, and chemical and bulk fuel storage systems. Recent independent tests evaluating the performance of F3 by LASTFIRE to extinguish increasingly larger diameter fires have been very successful in Europe (2017) and more recently at the Dallas Fort Worth Airport (2018).

Successful foam transition takes a well-developed, site-specific strategy. Some of the considerations associated with foam transition include:

Maintaining compliance with fire protection regulations and insurance accreditation;
Competent foam selection based on independent certifications, performance testing and analytical testing for composition;
Maintaining a functional fire suppression system to protect human health and assets;
Understanding of the design basis and operational knowledge of existing equipment;
Compatibility assessment of system components with new foam;
Effective decontamination of existing equipment to remove residual PFAS and prevent cross-contamination of new foam;
Proper planning for containment and disposal of waste generated during transition;
Effective secondary containment, and inspection and maintenance procedures are required; and,
Proportioning testing to establish performance of new foam.

Observations, results, data, and lessons learned from foam transition projects will be presented for various fire protection applications ranging from aviation hangars, to bulk fuel storage and chemical manufacturing.

From an environmental perspective, effective cleanout of residual PFAS from previous aqueous film forming foams (AFFF) usage is critical for a successful transition. Contamination of new foam from residual can render it no longer PFAS-free, creating future liabilities. While every system is different and requires assessment, water rinses alone have often been found to be ineffective. Biodegradable, nontoxic solvents have been developed and applied to piping and tank systems to achieve greater PFAS removal, which have greatly improved the mass removal of PFAS from a stainless-steel tank over that of water alone. Total oxidisable precursors (TOP) assay used to test flush water for PFAS content has highlighted the limitations of using only the standard PFAS analysis on foam-impacted fluids.

Ian Ross, Senior Technical Director, Arcadis UK
Ian Ross, PhD, is a senior technical director with Arcadis and the company’s global PFAS lead. He has focused on remediation for more than 25 years, designing and implementing innovative chemical, physical, and biological remediation technologies. He is currently focused on risk management and remediation of PFAS, with more than 14 years of experience working on PFAS projects.

Wood was contracted by the European Commission, Directorate-General for Environment (DG ENV) and by the European Chemicals Agency (ECHA) to provide services on 1) the use of per- and polyfluoroalkyl substances (PFAS) and fluorine-free alternatives in fire-fighting foams (the ‘DG ENV study’); and, 2) the assessment of alternatives to PFAS-containing fire-fighting foams and the socio-economic impacts of substitution (the ‘ECHA study’). Under the DG ENV Study, Wood assessed the use of PFAS and fluorine-free alternatives in fire-fighting foams, looking specifically at their volumes of use, their functionality, their emissions to the environment, and the costs for remediation of soil and water due to environmental release. Specifically, they evaluated 1) the potential hazard (and risk, to the extent possible) of fluorine-free alternatives, with regard to human health, the environment and humans exposed via the environment; 2) the cost and technologies for remediation of soil and water for both “long chain” and “short chain” PFAS and for the fluorine-free alternatives; and, 3) the above points for both foams already on the market and installed in fire-fighting systems (both fixed and mobile), as well as foams not yet in use.

Under the ECHA Study, they assessed the technical feasibility, economic feasibility and availability of alternatives to PFAS-containing fire-fighting foams and the socio-economic impacts of substitution, including a workshop with various industry stakeholders (including producers and users of fire-fighting foams) to gather input on use and replacement.

The intent of the work product is to gather and provide information as a basis for a decision on the appropriate regulatory measure to control the risks associated with the use of PFAS in fire-fighting foam.

Shalene Thomas, Emerging Contaminant Program Manager, Wood
Shalene Thomas, PMP, is the Emerging Contaminant Program Manager for Wood. She has more than 20 years of experience in environmental consulting that includes 11 years of experience supporting per- and polyfluoroalkyl substance (PFAS) evaluations. She has extensive program and project management, human health risk assessment, data management, GIS and 3D visualization and animation experience and has supported state, federal and industrial clients with PFAS evaluations. She serves as Wood’s PFAS Work Group Lead and has supported PFAS projects in 32 different states in nine of the ten US Environmental Protection Agency regions as well as in Australia and Canada.

Per- and polyfluoroalkyl substances (PFAS) pose many challenges for environmental managers, industry and environmental practitioners, due in part to their complex chemistry, poorly defined toxicology and environmental persistence and mobility. Firefighting foams containing PFAS (known as aqueous film forming foams [AFFF]) are a major contributor to ground and surface water contamination resulting from their routine use at airports, military facilities, and fire training areas. These AFFF materials contain many individual PFAS compounds, may be made by different manufacturers and have variable product composition.

Because AFFF mixtures are composed of numerous individual chemicals, analytical characterization using existing commercial methods is a significant challenge. The identity of many individual chemicals may not be known, standards may not be available and the mixture may contain many non-target chemicals (such as glycols and other surfactants). Currently, the standard laboratory approach for measuring PFAS can only quantitate 38 or so individual chemicals, using solid phase extraction and liquid chromatography/tandem mass spectrometry (LC/MS/MS). Other techniques are being developed and refined to expand this list and better understand the types of chemicals present. In particular, the total organic fluorine (TOF) analysis and total oxidizable precursor analysis (TOPA) provide additional insight into the composition of a PFAS mixture like AFFF. TOF helps evaluate whether the mass of fluorine containing organic chemicals is being identified using the standard PFAS analysis or whether large portions of material are not being quantified. TOPA degrades certain PFAS molecules that are not quantifiable under existing methods and converts them into terminal PFAS products, most of which are included in the standard analytical suite. Quantitative time of flight (QToF) analysis yields a qualitative structural analysis of which PFAS chemicals are most prevalent in a mixture.

An adequate characterization of AFFF product is key for managing existing stocks and for making decisions about maintenance and replacements. This presentation describes a tiered, analytically driven approach to provide a cost effective and scalable method for characterization of AFFF stock, based on the investigation and analysis of 274 AFFF product samples. Specifically, we use a PFAS analytical screening process of increasing sophistication to identify the product PFAS composition, with emphasis on identification of products that are most likely to contain those individual PFAS compounds considered to be the most toxic. The results of this screening process can aid in ranking which PFAS stocks pose the greatest risk and should be more carefully managed.

Heather Lanza, GHD
Heather Lanza has been working with PFAS for over five years in both the US and Australia. She has been extensively involved in multiple PFAS site investigations across Australia, where she has assisted in the development of sampling analysis and quality plans, field collection of abiotic media and biota, reporting for detailed site investigations, and she has led or assisted in the development of human health risk assessments (HHRA) and environmental risk assessments.

Heather has extensive experience in HHRA development for PFAS impacted sites. Her work through many stages of the projects has enabled a clear understanding of the site-specific requirements for each unique location, and she has participated in the stakeholder engagement component of many of the projects to date, including presenting the results of the assessments to relevant stakeholders, including community members.

Heather’s approach to PFAS requires acknowledgement of the potential issues, whilst highlighting the uncertainty in the current scientific evidence and looks to provide the client some context and balance in the face of often knee-jerk reactions to PFAS issues.