What Happened to PFAS Re-Openers?

The inclusion of PFOA and PFOS to the CERCLA hazardous substances list in 2024 prompted more than a few organizations and industry concerns for “re-openers” at sites on the National Priorities List (NPL). A primary concern was that EPA would “re-open” the existing decision documents (Record of Decisions [RODs], Explanations of Significant Differences [ESDs] and ROD Amendments) to add PFOA and /or PFOS as “contaminants of concern” upon completion of a Five-Year Review (FYR), thus requiring additional remedial actions to address those PFAS. This was particularly significant for sites in the postremedial Operations and Maintenance (O&M)/Long Term Monitoring (LTM) stages of the CERCLA process. Nearly all of these sites are subject to FYRs, which are conducted by EPA to document that the completed remedial actions continue to be protective of the human and ecological receptors identified in the CERCLA decision document. Based on the number of industries now suspected as having managed per- and polyfluoroalkyl substances (PFAS) in some capacity, a great number of the sites are potentially subject to the re-opener scenario. But do we see recent evidence of this occurring?

EPA, or other Federal Agencies with authority to implement CERCLA, prepare a sizeable number of FYRs annually, and according to EPA Superfund Remedial Annual Accomplishment Reports for FY2021 through FY 2025, they averaged about 269 FYRs per year, or over 1,300 FYRs over the last five years (Superfund Accomplishments Report Fiscal Year 2025 | US EPA). Interesting side note: EPA currently reports 1,248 NPL sites have reached the Construction Completion stage (Construction Completions at National Priorities List (NPL) Sites – by Number | US EPA), which ties in well with the reported number of FYRs from the last five years.

AlterEcho has been reviewing FYRs published by EPA over the last few years to determine how the PFOA and PFOS CERCLA designations may impact NPL sites moving forward. There are numerous examples where EPA has included site-specific recommendations in FYRs for additional PFAS characterization and monitoring, mostly for groundwater, and this started before PFOA and PFOS were added as hazardous substances. However, in order to be considered a “re-opener” resulting from the FYR process, PFOA and PFOS would need to be added as site-related contaminants of concern (COCs) to an ESD or ROD Amendment. Since EPA tracks “contaminants” at Superfund sites only after they are included in a ROD, ESD, or ROD Amendment, AlterEcho searched EPA’s Superfund Enterprise Management System (SEMS) database, entering PFOA and PFOS as “contaminants” into the system. That search resulted in only 15 NPL sites with PFOA and/or PFOS as contaminants (or COCs). [Please note, while AlterEcho conducted a search for PFOA and PFOS as COCs in EPA’s SEMS database to determine the link between NPLwww.alterecho.comsites and PFOA/PFOS, it is possible that PFOA and PFOS have yet to be entered into SEMS for certain sites].

Excluding Federal Facility sites where PFAS have been investigated to a greater extent than at private/PRP-led sites, there are only three sites where PFOA and/or PFOS have been added as COCs through ESDs or ROD Amendments. These three sites are all in the Northeast and include the Valmont TCE Site in Pennsylvania (VALMONT TCE SITE (FORMER – VALMONT INDUSTRIAL PARK) | Superfund Site Profile | Superfund Site Information | US EPA), the New Hampshire Plating Company in New Hampshire (NEW HAMPSHIRE PLATING CO. | Superfund Site Profile | Superfund Site Information | US EPA) and the Old Wilmington Road Groundwater Contamination site in Pennsylvania (OLD WILMINGTON ROAD GW CONTAMINATION | Superfund Site Profile | Superfund Site Information | US EPA).

There are also a few sites that were more recently listed on the NPL, where PFOA and/or PFOS are included as COCs in RODs, such as the Blades Groundwater Site in Delaware (BLADES GROUNDWATER | Superfund Site Profile | Superfund Site Information | US EPA) and a “new” Operable Unit at a site that has been on the NPL since the 1980s: the Landfill & Resource Recovery, Inc. (L&RR) site in Rhode Island (LANDFILL & RESOURCE RECOVERY, INC. (L&RR) | Superfund Site Profile | Superfund Site Information | US EPA). However, PFOA and PFOS were not added to the Blades and LR&R sites as a result of and ESD or ROD Amendment, and are therefore not considered “re-openers.”

AlterEcho’s search also revealed several sites that were added to the NPL over the last five years where PFAS are currently being investigated, but the sites are in the “pre-ROD” stage, so EPA does not appear to be tracking PFOA and PFOS at those sites as COCs. Examples here include the Galey & Lord Plant site in South Carolina (GALEY AND LORD PLANT | Superfund Site Profile | Superfund Site Information | US EPA) and the East Basin Road Groundwater site in Delaware (EAST BASIN ROAD GROUNDWATER | Superfund Site Profile | Superfund Site Information | US EPA). When RODs are prepared for these sites and other newly-listed sites, PFOA and/or PFOS will likely be included as COCs, but again, they will not be considered “re-openers.”

Finally, AlterEcho’s review found eight Federal Facilities on the NPL where PFOA and/or PFOS are listed as COCs. It appears that PFOA and/or PFOS were added as COCs through various decision documents, including ESDs and CERCLA Non-time Critical Removal Actions. The low number of Federal Facility sites with PFOA and PFOS identified as COCs may seem surprising based on the relatively significant PFAS investigations that have taken place at Department of Defense (DoD) facilities, particularly Air Force sites. However, DoD has followed the CERCLA pre-remedial (Preliminary Assessment/Site Inspection) and remedial (Remedial Investigation [RI]/Feasibility Study [FS]) process in its PFAS investigations, and few of those sites have even reached the FS stage. Once the decision documents have been contemplated at those sites, we should see an increase in PFOA and PFOS listed as COCs at these Federal Facilities.

So, what does the small number (three) of private Superfund re-opener sites tell us? It is likely attributable to a few factors. First, it appears EPA’s decision for adding PFOA or PFOS as COCs is based on known impacts to human health and the environment. At sites where PFAS have been detected above regulatory standards or screening levels, but there are well managed land use controls preventing human exposures, it does not appear that EPA is moving forward with decision document revisions, at least at this time. Second, the extent of any PFAS contamination in site environmental media and potential human/ecological exposures are still being investigated at several Superfund sites, thus EPA does not have sufficient data to make a decision regarding decision document revisions. Third, preparing an ESD or ROD Amendment can require considerable Agency resources (in addition to subsequent RD/RA resources), so EPA is probably looking closely at its resources versus the need to protect against PFOA and PFOS exposures. One could also envision that the uncertainty prior to the August 18, 2026 U.S. Court of Appeals for the District of Columbia Circuit upholding EPA’s listing of PFOA and PFOS as hazardous substances contributed to less re-openers. But, it’s more likely the first three scenarios discussed above that have limited the number of re-openers. As EPA receives and reviews additional PFAS data currently being collected at dozens (maybe hundreds) of NPL sites, it is likely that we will see additional ESDs and ROD Amendments. However, they should be expected to trickle in, not be the onslaught that many predicted a few years ago.