PFAS are a group of manmade fluorinated chemicals that have been manufactured and used in a variety of industries since the 1940’s. PFAS are persistent in the environment and the human body, and there is evidence that exposure to PFAS can lead to adverse health effects as well as ecological risks. PFAS are considered to be contaminants of emerging concerns, with regulatory standards that are evolving due to new science, detection capabilities, and transport pathways. The Environmental Protection Agency has issued Health Advisories at parts per trillion levels in drinking water for two PFAS compounds (PFOA, PFOS), and many State Environmental Agencies are regulating additional PFAS compounds as well as lowering groundwater standards for PFOA and PFOS. Without Federal Maximum Contaminant Level standards for PFAS compounds, States have regulated various PFAS compounds at varying standards. Many of the States regulating PFAS in drinking water have just as stringent standards for groundwater. Additionally, large industrial PFAS air deposition areas exist, with no Federal guidance yet on soil leaching standards, leaving Transportation Agencies to evaluate the risk and liability of relocating PFAS-impacted soil.
DOT agencies like New Hampshire DOT are, or will likely be, navigating problems pertaining to PFAS due to the following situations: DOT owned legacy sites with PFAS impact; road construction and improvement through soil in areas with PFAS aerial deposition; increased assessment and analytical cost for soils to be graded, cut, or excavated; storage and disposal of spoil materials from road way maintenance in areas with PFAS aerial deposition; and, PFAS impact in dewatered construction groundwater and the requisite parts per trillion treatment goals.
A Synthesis Project is needed to document the status of PFAS regulation, various aspects of the impacts of PFAS on Transportation Agencies and provide a reference document for Transportation Agencies.
A Synthesis Project of this scale is beyond most DOT capabilities, in terms of available personnel and expertise. Given all of the emerging elements of PFAS, especially analytical methods and uniform soil and groundwater health criteria, a national perspective PFAS reference document will be invaluable at this juncture as an essential basis for DOT policy formulation regarding PFAS management.
The anticipated scope of the Synthesis Project based on the available information in the literature should include:
- A brief overview of PFAS chemistry, nomenclature, properties, industrial development and applications;
- A status of the U.S. and international regulatory environment for PFAS as it pertains to Transportation Agencies, particularly in light of EPA PFAS Action Plan (February 2019);
- A summary of products used by Transportation Agencies which are known or suspected to contain PFAS;
- A survey of historical and current practices regarding the procurement, storage, use, removal and disposal of PFAS-containing products and soil material;
- Transportation agency guidance for the procurement, storage, use, removal and disposal of PFAS-containing products and soil material;
- Assessment of replacements to PFAS-containing products;
- A screening tool to determine potential areas of concern for PFAS during the NEPA process;
- Quality assurance considerations for sampling and analysis for PFAS;
- Guidance for geotechnical explorations in known or suspected PFAS-impacted areas;
- Disposal or relocation and treatment options for waste construction water or soil impacted by PFAS;
- On-site remediation technology options for PFAS-impacted Construction dewatering and migration in soil for various PFAS compounds; and
- Recommendations for further research related to PFAS and Transportation Agency Practices.
Environmental Division in State DOTs
TRB ADC60 Committee, TRB AFP40 Committee
National Academies of Sciences, Engineering, and Medicine 2017. Use and Potential Impacts of AFFF Containing PFASs at Airports. Washington, DC: The National Academies Press. https://doi.org/10.17226/24800.
Literature from the Environmental Protection Agency, New Hampshire Department of Environmental Services, Interstate Technology & Regulatory Council