PFAS Remediation Under CERCLA: A New Technical Frontier
The designation of PFOA and PFOS as CERCLA hazardous substances in 2024 opened the door to large-scale Superfund remediation projects at PFAS-contaminated sites — military installations, industrial facilities, firefighting training sites, and landfills. For water treatment technology providers, this represents a significant shift in the types of remediation projects being specified and the technical requirements those projects impose.
CERCLA remediation projects are technically demanding in ways that standard drinking water treatment projects are not. Remediation sites often involve highly variable influent concentrations — sometimes orders of magnitude higher than MCL-level contamination — as well as complex matrices that include co-contaminants, high dissolved organic carbon, and competing ions that can impair filter performance. The technology specifications emerging from these projects reflect that complexity.
How Remedial Investigation Findings Are Driving Technology Selection
At Superfund sites, technology selection is driven by the Remedial Investigation/Feasibility Study (RI/FS) process. The RI characterizes the nature and extent of contamination; the FS evaluates treatment alternatives against criteria including long-term effectiveness, reduction of toxicity and mobility, implementability, and cost. For PFAS-contaminated sites, FS evaluations are now required to consider a broader compound set than was typical even two years ago.
Remedial project managers (RPMs) and their technical consultants are increasingly specifying filter technologies that must demonstrate performance across the full PFAS compound spectrum identified in the RI — which at many sites includes short-chain compounds that were either not analyzed in earlier investigations or were detected at concentrations that were previously not actionable. This has created demand for treatment technologies with demonstrated broad-spectrum PFAS removal, evaluated under site-specific matrix conditions rather than standard challenge water.
The practical implication is that technology vendors responding to Superfund remediation RFPs are expected to provide performance data under conditions approximating the site matrix — not just clean water performance data. This is a meaningfully higher bar than what was required in most pre-2024 procurement processes.
Treatment Train Specifications and Media Selection Criteria
Large-scale PFAS remediation projects typically require treatment trains that address multiple contaminant classes simultaneously. At many sites, PFAS co-occurs with chlorinated solvents, heavy metals, or other regulated compounds. The filter media selected for PFAS removal must therefore perform within a treatment train context — not interfere with other treatment processes, not be compromised by co-contaminants, and not create secondary waste streams that complicate the overall site remedy.
Granular activated carbon remains the most commonly specified PFAS adsorbent in Superfund treatment trains, largely because of its extensive regulatory track record and available field data. However, RPMs and technical consultants are increasingly evaluating PFAS-selective adsorbents — including ion exchange resins and newer engineered adsorbents — for applications where GAC performance is insufficient, particularly for short-chain PFAS removal or where high dissolved organic carbon loading reduces GAC efficiency significantly.
Record of Decision Language and Long-Term Compliance
The technology specifications in a Superfund Record of Decision (ROD) have long-term implications because they define the remedy that EPA and the responsible party have agreed to implement. RODs for PFAS-contaminated sites are now being written to include provisions for remedy optimization — specifically, the ability to modify treatment technology if performance does not meet remedial action objectives (RAOs) for the full compound set.
This means that responsible parties and their contractors should be evaluating not just current treatment performance, but adaptability. A treatment system specified today must be capable of meeting RAOs for compounds that may be added to the regulatory list as EPA’s PFAS designation process continues. Technologies that can be upgraded or supplemented — for example, by adding a polishing stage with PFAS-selective media — will be more defensible in ROD negotiations than single-technology solutions with limited adaptability.
Implications for Technology Vendors Responding to Remediation RFPs
Vendors responding to Superfund PFAS remediation RFPs should anticipate several requirements that may not appear in municipal drinking water procurements: site-specific treatability study data; performance guarantees tied to RAOs rather than MCLs; documentation of spent media management under RCRA as well as CERCLA frameworks; and detailed operation and maintenance plans covering the full anticipated remediation period, which at many sites will be measured in decades rather than years.
The financial stakes at Superfund sites are also substantially higher than at typical municipal installations, and the procurement process reflects that. Technical proposals are evaluated with significant rigor, and past performance on comparable remediation projects carries significant weight. Building a documented track record in PFAS remediation — including performance data on short-chain compounds and complex matrices — is becoming a competitive necessity for vendors targeting this market segment.