On December 20, 2019, the United States Environmental Protection Agency (EPA) issued its Interim Recommendations for Addressing Groundwater Contaminated with Perfluorooctanoic Acid (PFOA) and Perfluorooctanesulfonate (PFOS) under federal cleanup programs, such the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Resource Conservation and Recovery Act (RCRA). EPA’s guidance recommends the use of a “screening level” of 40 parts per trillion (ppt) to determine if either PFOA or PFOS is present at a site for purposes of evaluating further remedial action, and EPA’s PFOA and PFOS Lifetime Drinking Water Health Advisory (HAL) of 70 ppt as the site’s “preliminary remediation goal.”
What is the difference between a “screening level” and a HAL?
In its Soil Screening Guidance: User’s Guide, EPA notes that a “screening level” is a tool to identify the presence of contamination at a site and to determine if further action is necessary. Sites that have contaminations below a risk-based “screening level” (40 ppt in EPA’s guidance, noted above) may not warrant further action or study. Exposure above a screening level does not mean that health problems will occur but may be a signal to remediators to further assess the exposure to contamination at a particular site.
In comparison, a HAL, under the federal Safe Drinking Water Act, describes concentrations of contamination at or below which adverse health effects are not anticipated to occur over a certain amount of exposure. The PFOA and PFOS HAL, of 70 ppt is based on a lifetime exposure and serves as a “preliminary remediation goal” that can inform EPA’s development of final cleanup levels at specific sites.
For more information on the 2020 regulatory status of PFAS with the EPA, click here.