Down the Drain but Not Forgotten: PFAS Compliance in Wastewater

Per- and polyfluoroalkyl substances in wastewater are among the most significant and fastest-moving emerging environmental compliance challenges manufacturers will confront. 

While early legal attention focused on PFAS in drinking water, federal and state legal frameworks have flowed downstream into wastewater discharges regulated principally under the Clean Water Act, analogous state laws and their implementing regulations.

Those wastewater obligations do not operate in isolation: the same PFAS a facility discharges or monitors can trigger liability under the Resource Conservation and Recovery Act, the Comprehensive Environmental Response, Compensation, and Liability Act, the Toxic Substances Control Act, and a growing body of analogous state laws.

This article focuses on manufacturers’ wastewater obligations under the CWA and explores how these responsibilities connect to broader, cross-statute liability.

Like a (waste) water park, manufacturers’ compliance obligations stream from several directions at once and are evolving daily, so proactive risk management is critical. 

Pfail to plan, plan to pfail. 

PFAS-Specific Limits Contemplated for Wastewater Dischargers 

EPA has not yet set PFAS-specific industrial wastewater discharge limits under the CWA; however, the agency is studying how much PFAS enters publicly owned treatment works (POTWs) from industrial (and domestic) sources.

On July 1, 2026, EPA issued new draft guidance (Docket ID No. EPA-HQ-OW-2026-2509) to reduce risks from PFOA and PFOS in biosolids. 

Although the guidance addresses residuals rather than effluent, it signals the regulatory pressure building on the discharge side and previews source-control expectations.

The guidance signals the regulatory pressure building on the discharge side and previews source-control expectations.

EPA appears to be focused on industrial wastewater sources as contemplated under proposed CWA pretreatment requirements, rather than the treatment plants that receive their wastewater. 

For example, EPA has indicated it will pursue effluent limitation guidelines (ELGs) for PFAS chemical manufacturers and metal finishers with the express goal of stopping PFAS at the source. 

These ELGs remain at the proposed/development stage, however, and their pace, scope and ultimate survival are subject to shifting federal priorities, so manufacturers should continue to monitor. 

Wastewater Discharge Permitting and Monitoring Becomes the Front Line 

In the absence of numeric federal limits under the CWA, wastewater discharge permitting has become a leading focus of EPA and states.

Through the National Pollutant Discharge Elimination System program, EPA has encouraged state permitting authorities to require PFAS monitoring, identify industrial sources, and impose upstream pretreatment or best management practices where appropriate.

EPA’s finalized analytical Method 1633 for wastewater (which measures 40 PFAS) now provides the technical backbone for these monitoring requirements and is increasingly written into permits.

Pretreatment Pressure  

For manufacturers that discharge to POTWs, CWA pretreatment programs are the most immediate pressure point.

Under those programs, POTWs hold broad authority (e.g., through local permits, ordinances, and enforcement actions) to regulate the industrial users that send wastewater their way.

For manufacturers that discharge to POTWs, CWA pretreatment programs are the most immediate pressure point.

To date, PFAS pretreatment has leaned on BMPs rather than hard numeric discharge limits.

However, with several states reporting PFAS load reductions of more than 90 percent through robust pretreatment programs, treatment plants now have both the incentive and precedent to impose aggressive source control on their upstream industrial contributors.

The State Patchwork: Sampling, Monitoring & Reporting 

Predictably, state CWA programs have generally moved faster than the federal government, creating a patchwork that complicates life for any manufacturer operating in more than one jurisdiction. 

Connecticut (and other states) impose sampling and reporting requirements on significant industrial users to build the data foundation to support the imposition of future permit limits. 

Connecticut’s Department of Energy and Environmental Protection is incorporating PFAS monitoring conditions into water discharge permits.

On July 6, 2026, DEEP’s Water Permitting and Enforcement Division issued the PFAS Roadmap for Industrial Discharges 2.0, updating its 2023 NPDES & Pretreatment Roadmap to outline key regulatory trends for PFAS monitoring, effluent limits and reporting for known or suspected PFAS discharges across its permitting programs.

Connecticut’s DEEP is incorporating PFAS monitoring conditions into water discharge permits.

This, together with Connecticut’s broader PFAS statutory program (including product phase-outs), signals where enforceable requirements are likely headed. 

Michigan, Wisconsin, Maine, New York, and others already require PFAS-specific monitoring and discharge minimization plans, and in some cases impose numeric effluent limits (e.g., for individual PFAS compounds such as PFOS and PFOA).

With differing standards/requirements in multiple states, this divergence can translate directly into greater operational complexity, higher compliance costs, and broader litigation exposure. 

Cross-Statute Liability 

On top of the state patchwork, manufacturers need to prepare for cross-statute liability.

Simply put, the same PFAS a facility discharges in wastewater can create exposure under other federal and state laws.

Under the federal Emergency Planning and Community Right-to-Know Act, more than 200 PFAS are now subject to annual Toxics Release Inventory reporting, and EPA has eliminated the de minimis exemption for PFAS (materially increasing the reporting burden).

A separate one-time PFAS reporting rule under TSCA Section 8(a)(7) was finalized in 2023; EPA proposed amendments in November 2025 that, if finalized and as relevant here, would narrow reporting by exempting byproducts and impurities. 

Byproduct and impurity determinations often arise from process streams, treatment residuals, and other PFAS-bearing wastewater-related materials.

The same PFAS a facility discharges in wastewater can create exposure under other federal and state laws.

These amendments are not yet final, so manufacturers should monitor EPA’s proposed amendments and continue to preserve records supporting their PFAS waste-stream determinations.  

Most consequentially, EPA’s 2024 designation of PFOA and PFOS as CERCLA hazardous substances exposes manufacturers to potential investigation and cleanup liability for releases associated with wastewater discharges and PFAS-bearing sludge or biosolids sent off site for disposal or land application. 

The CERCLA rule has been challenged in court, and EPA has issued an enforcement-discretion policy signaling it will focus on major PFAS manufacturers and industrial dischargers rather than passive receivers such as POTWs and water utilities.  

Additional Risks

Manufacturers should also watch RCRA.

EPA proposed to list several PFAS as hazardous constituents and to confirm that its RCRA corrective-action authority reaches emerging contaminants like PFAS, developments that could expand cleanup and waste-handling obligations at manufacturing facilities.

The biosolids connection is practical as much as regulatory: PFAS in industrial wastewater can flow into treatment residuals, spent filters, sludges and other waste streams, potentially implicating obligations under RCRA. 

Upstream source control and careful waste characterization may reduce downstream disposal, land-application and corrective-action risk. 

Taken together, these initiatives suggest an integrated federal approach that reaches manufacturers through permitting, reporting, pretreatment, residuals management, and potential cleanup obligations. 

These initiatives suggest an integrated federal approach reaching manufacturers throughout the entire process.

Finally, manufacturers should be aware of two more liability risks.

First, the CWA’s citizen-suit provision allows plaintiffs to enforce permit terms and monitoring or reporting requirements directly against dischargers, making accurate PFAS sampling and disclosure (under, e.g., the TSCA Section 8(a)(7) rule) a litigation-sensitive obligation.

Second, state cleanup and property-transfer liability regimes can impose remediation obligations that operate independently of, and sometimes reach further than, federal CERCLA (an important consideration for any facility with historical PFAS use).

Those state legal risks can arise where PFAS-containing wastewater or residuals were routed to POTWs, landfills, land-application sites or other disposal locations and later become the focus of investigation, cleanup, cost recovery or transaction diligence. 

What Manufacturers Should Do Now 

In a landscape this fluid, proactive risk management is essential.

Manufacturers should work with experienced technical and legal advisers to develop a privileged PFAS risk management plan.

A sound RMP identifies (as early as possible) and characterizes PFAS in process streams, raw materials and waste/wastewater discharges (both looking forward and backward); scrutinizes the sampling and effluent obligations that EPA/states are beginning to impose; and can help coordinate compliance obligations across multiple federal and state legal frameworks. 

Chart a course now before the PFAS wastewater discharge floodgates fully open. 

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For more information about Shipman’s manufacturing practice, please contact Alfredo Fernández at 860.251.5353 or [email protected].