Per- and polyfluoroalkyl substances (PFAS) are a class of contaminants of emerging concern that can harm both ecosystems and human health. These anthropogenic compounds contain carbon-fluorine bonds, which make them stable and persistent in the environment, earning them the nickname “forever chemicals.” PFAS regularly migrate from sources of contamination, including fire training areas at military sites and airports, PFAS manufacturing sites, land-applied wastewater biosolids, and landfills. PFAS can be found at low levels in soils and water far from any likely source.

There are currently no binding federal regulations for PFAS. However, the EPA has begun the process of designating several PFAS as hazardous substances. This designation would likely restrict the ways in which state departments of transportation (DOTs) handle and dispose of impacted materials. The objective of this synthesis was to document current state DOT practices for identifying locations of potential PFAS contamination and for mitigating the impacts of PFAS related to highway construction and maintenance operations.

Information for this study was gathered through a literature review, a survey of state DOTs, and follow-up interviews with selected DOTs. Case examples of eight state DOTs provide additional information on identifying and mitigating PFAS impacts on highway construction projects and maintenance operations.

The report is available.