From 2008 to 2014, Antea Group participated in a source investigation of per- and polyfluoroalkyl substances (PFAS) in water and soil, tasked with completing a U.S.-based region-wide survey of potential PFAS sources for a confidential client. PFAS has been identified in soil, sediment, surface water and groundwater in various locations around the globe and within the U.S., and these detections may be coincidental with Class B AFFF use such as in firefighting training exercises or in large quantity to extinguish fires. Given that certain types of aqueous film-forming foam, or Class B AFFF, have a fluorochemical-based surfactant that is known to contain PFAS, AFFF was suspected as a potential source of PFAS.
Antea Group surveyed personnel from local municipal and private industrial fire departments and firefighting training facilities, such as refineries and airports, regarding their use and knowledge of firefighting foams. Our team then ranked firefighting training sites and fire sites where Class B AFFF is or was used for their potential to release PFAS to the environment based on several criteria, including: the types and amounts of AFFF used, the frequency of use, the site environmental setting, potential migration pathways to the environment, and the presence of nearby receptors such as water supply wells and surface waters.
Based on the site ranking, several firefighting training and fire sites where Class B AFFF was discharged were identified as potential PFAS sources and selected for further investigation. Antea Group completed these additional investigation activities including site reconnaissance, in-depth interviews, and sampling of potentially affected media including groundwater, soil, surface water or sediments.
Antea Group found that PFAS were present in the environment above background at sites where Class B AFFF was discharged repeatedly in training exercises or where large amounts of AFFF was utilized on Class B fires. In many cases, PFAS in surface water or groundwater were at concentrations above the available state or federal screening or advisory levels for drinking water, so it was important for the client to have that full visibility in order to take corrective action.