EPA has released draft interim groundwater screening levels and preliminary remediation goals (PRG) for PFAS where the groundwater is a current or potential source of drinking water. These draft levels are only for two PFAS compounds, PFOA and PFOS.
For a quick background on PFAS, see our prior blog post, “Fast Facts: What is PFAS?”
The draft interim screening level is 40 parts per trillion (ppt) for each compound individually. As stated by EPA, “screening” is “the process of identifying and defining areas, contaminants, and conditions at a particular site that may warrant further attention.” They are not technically cleanup levels per se, but indicate that further risk assessment activities are warranted.
The draft PRG is set at the current health advisory level of 70 ppt for PFOA and PFOS combined. EPA states that PRGs can be adjusted based on site-specific information, but also: “In situations where groundwater is being used for drinking water, EPA expects that responsible parties will address levels of PFOA and/or PFOS over 70 ppt.”
It’s important to note that this PRG is applicable only where no state or tribal drinking water standard or other applicable or relevant and appropriate requirements (ARARs) exist. For states that set their own drinking water standard or set a standard for PFAS compounds other than PFOA and PFOS, the state criteria would be used to establish the PRG.
While the screening level and PRG are by no means drinking water standards established under the Safe Drinking Water Act, it will be interesting to see how these draft values from EPA will affect regulatory developments in states, like Michigan, that are working towards setting their own maximum contaminant levels (MCLs) for PFAS compounds. It will also be interesting to see the Department of Defense’s reaction, as it has recently communicated its position that the unacceptable risk for cleanup of groundwater impacted by PFOA and PFOS is approximately 380 ppt—more than five times than what EPA has proposed.
EPA first announced that it was developing groundwater cleanup recommendations in May 2018, following its national PFAS leadership summit. EPA confirmed that it was taking this action in its PFAS Action Plan, released on February 14. EPA also has stated it is reviewing designating PFOA and PFOS as CERCLA hazardous substances, and it is notable that EPA has released these draft values before making that designation.
Additionally, EPA’s prior statements were related generally to groundwater, but the draft levels the agency announced on April 25 appear to only pertain to groundwater that is or could be used as drinking water. Importantly, EPA only has an approved PFAS analytical method for drinking water; it is reportedly working on methods for other matrices, including groundwater, but the agency has yet to publish other methods for review.
The draft interim screening levels and PRGs are available for public comment for 45 days, with the comment period expiring on June 10, 2019.
