PFAS Perspectives: Navigating the PFAS Seas: Charting Your Course Amidst the Recent Wave of PFAS Regulations

Authors:

Kyle McDonald, CES, Project Scientist, Trihydro Corporation

Fritz Krembs, P.E., P.G., Engineering Specialist, Trihydro Corporation

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For those navigating the ever-changing sea of per- and polyfluoroalkyl substances (PFAS) developments, it may seem like the wave has finally crashed ashore.? In recent months, the United States Environmental Protection Agency (USEPA) released a series of significant announcements with wide-ranging implications, including finalizing highly anticipated maximum contaminant levels (MCLs) and hazardous substance designations under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA; also known as Superfund).? Alongside these major rulings, the USEPA has issued additional guidance and policies to clarify their implementation.? In this issue of PFAS Perspectives, we dive into the murky depths to help NORA members stay afloat amid these recent federal developments.

Anchoring Regulations: Finalization of MCLs for PFAS Compounds

On April 26, 2024, the USEPA published final PFAS MCLs in the Federal Register, making the rule effective on June 25, 2024.? This significant Safe Drinking Water Act (SDWA) development concerns the National Primary Drinking Water Regulation (NPDWR) for six PFAS compounds: PFOA, PFOS, PFNA, HFPO-DA, PFHxS, and PFBS.? The final rule aims to place further controls on PFAS as outlined in the USEPA’s? PFAS Action Planand Strategic Roadmap, which together aim to better prevent and manage human health and the environment.?

The NPDWR includes legally-enforceable MCLs and non-enforceable MCL Goals (MCLGs).? MCLs set the maximum allowable concentration of a contaminant in public drinking water systems, while MCLGs represent the level at which there is no known or expected risk to human health. ?While MCLGs are generally set to lower, more stringent levels, MCLs are intended to consider logistical challenges, such as the types and costs of available treatment technologies and analytical detection limits.? Promulgated MCLs require public drinking water systems to complete initial monitoring for these PFAS compounds by 2027 and to implement processes to prevent these contaminants from exceeding the MCLs by 2029.?Non-compliance can lead to potential USEPA enforcement actions.?

USEPA has set final individual MCLs for five PFAS compounds: PFOA and PFOS at 4 parts per trillion (ppt) each and PFHxS, PFNA, and HFPO-DA (commonly referred to as Gen-X) at 10 ppt each.? Additionally, the MCLs include a Hazard Index (HI) approach to regulate cumulative exposures. This approach requires calculating a Hazard Quotient (HQ) for four co-occurring PFAS (PFNA, PFHxS, PFBS, and HFPO-DA), with the HI being the sum of HQs for the four constituents. If the cumulative HI equals or exceeds 1, MCL compliance conditions are violated, necessitating corrective actions.? Notably, PFBS is included only in the mixture HI approach and does not have an individual MCL.?

This final ruling marks a significant regulatory development, originating from USEPA’s examination of potentially regulating certain PFAS chemicals over two decades ago.? Federal health-based standards for PFAS have been a moving target over the past fifteen years fluctuating from sub-parts per billion levels (2009 non-enforceable health advisory levels) down to the parts per quadrillion level (2022 interim updated health advisory level).? Stakeholders and state agencies have awaited these criteria, which provide standards for PFAS, though USEPA periodically reviews NPDWRs and may adjust MCLs based on new scientific evidence.?

A 2023 US Geological Survey (USGS) study estimates that at least 45% of the country’s tap water may have detectable PFAS and data from the ongoing Fifth Unregulated Contaminant Monitoring Rule (UCMR5) indicate that 10% of the responding public water systems (PWSs) have reported concentrations of PFAS exceeding the newly regulated MCLs.? The UCMR5 program requires sampling for 29 PFAS compounds in PWS’s across the country with final results expected by 2026. Compliance costs are also anticipated to be substantial with a 2023 American Water Works Association (AWWA) study estimating costs to exceed $3.8 billion annually to treat PFOA and PFOS to 4 ppt, which is refuted by USEPA in the final ruling as “substantially overestimated.”?

The USEPA evaluated Best Available Technologies (BAT) to comply with the new MCLs and identified granular activated carbon (GAC), ion exchange (IX), and high-pressure membrane separation via reverse osmosis or nanofiltration (RO/NF) for drinking water treatment. Many of these technologies are additionally appropriate with other matrices, such as groundwater and landfill leachate, though complex chemistries complicate their efficacies. The USEPAs BAT evaluation concludes that while these technologies are generally effective for removing newly regulated PFAS compounds from drinking water streams, they lead to PFAS-concentrated residuals that require disposal or destruction.

Casting a Wide Net: Implications of PFAS Designations under CERCLA

Shortly after the issuance of final MCLs, on May 8, 2024, USEPA designated PFOA and PFOS (and their salts and structural isomers), as hazardous substances under CERCLA, effective July 8, 2024. This ruling has broad implications for release notifications, transportation manifesting, and reporting under other regulations like the Clean Water Act and the Toxics Release Inventory.? The designation aims to hold “significant polluters” accountable and increase transparency about these compounds’ release.?

CERCLA grants USEPA authority to require potentially responsible parties (PRPs) to investigate and cleanup contaminated sites and to pursue cost recovery and contributions under joint and several liability.? In the past, these compounds required USEPA and other authorized agencies to prove “imminent and substantial” danger to public health or the environment before responding to releases.? The finalization of this designation eliminates that requirement for PFOA and PFOS, enabling response to a broader range of releases.? The designation of a hazardous substances does not, in and of itself, require further investigation or cleanup, but the rule is expected to impact existing and closed CERCLA sites via the five-year review process, with the possibility of re-opening formerly closed CERCLA sites and delays for sites nearing closure.? Many states adopt CERLCA hazardous substances into their own cleanup statutes, potentially mandating state-level remediation of PFOA and PFOS.? While the USEPA’s CERCLA listing is separate from the drinking water standards codified with drinking water MCLs, the CERLCA ruling states that the MCLs may be applicable or relevant and appropriate requirements (ARARs) for cleanup at contaminated sites.?

The designation includes mandatory reporting of releases over the reportable quantity (RQ) of 1 pound or more over a 24-hours to the National Response Center.? It also affects real estate transactions and mergers by resuming the suspended rulemaking of the Standards and Practices for All Appropriate Inquiries regulations and requiring covenant warranties for Federal property transactions.?

The USEPA’s PFAS Enforcement Discretion and Settlement Policy, released alongside the CERCLA designations, aims to hold “major PRPs” accountable while exempting “passive receivers” where equitable factors do not support seeking response action or costs.? This includes various entities such as community water systems, publicly-owned treatment works, municipal facilities, and farmland owners who’ve applied PFAS-laden biosolids.? The enforcement discretion may be extended to additional entities based on factors like governmental status, public service role, involvement in PFAS activities, and manufacturing or industrial use of PFAS.? Importantly, the policy is just that – a policy – and it does not hold equivalent weight of a codified regulation allowing for future deviations.? Additionally, the USEPA’s enforcement policy holds no bearing on preventing private party torts, litigation, or cost recovery actions under the new CERCLA ruling.

EPA has stated that the CERCLA ruling does not evaluate costs when designating hazardous substances.? However, direct and indirect costs resulting from enforcement of the CERCLA ruling were included in the final regulation.? USEPA estimates that nationwide notification of PFOA and PFOS releases may cost $2,658 per release ($1.63 million annually) and indirect costs for response at non-National Priorities List (NPL) sites may range between $327,000 to $18.1 million per year.? This is in stark contrast to estimates provided by the US Chamber of Commerce that private sector CERCLA liabilities may cost between $700 to $800 million per year, and could exceed $17 billion in total.?

The CERCLA listing does not classify PFOA or PFOS as hazardous constituents or hazardous wastes under the Resource Conservation and Recovery Act (RCRA), but mandates hazardous materials classification of the two chemicals for the purpose of transportation under the U.S. Department of Transportation (USDOT).? In response to petitions by the University of California Berkeley, the Public Employees for Environmental Responsibility (PEER), and the governor of New Mexico, RCRA hazardous constituent listings for PFOA, PFOS, and seven additional PFAS compounds were proposed by USEPA on February 8, 2024.?

The potential listing of a compound as a RCRA hazardous constituent does not by itself immediately impose regulatory requirements; however, RCRA hazardous constituents are cited by reference in several sections of federal hazardous waste regulations.? If finalized, a primary near-term impact of the hazardous constituent rule would involve consideration for further investigation and cleanup at more than 1,700 RCRA hazardous waste treatment, storage, and disposal facilities (TSDF) with solid waste management units (SWMUs) currently being addressed under the RCRA corrective action program.?? The worst-case scenario for this is the potential to re-elevate sites nearing completion of RCRA corrective actions back to an assessment and evaluation stage.? Further, the listing as a hazardous constituent sets the stage for potential longer-term reclassification of select PFAS compounds as a hazardous waste; a designation with significant implications across various sectors.? The process of reclassification to a hazardous waste requires USEPA to consider several factors specified under 40 CFR 261.11(a)(3) including whether the hazardous constituent represents a substantial hazard if improperly managed.? The timing of these subsequent steps remains uncertain and are dependent upon finalization of the currently proposed hazardous constituent rule. ??

Sailing in a Fog: No Lifeline in USEPA’s Destruction and Disposal Guidance

While the MCL and CERCLA rulings have garnered well-deserved attention, another significant development was recently released by USEPA.? On April 8, 2024, the USEPA updated its Interim PFAS Destruction and Disposal Guidance. This update builds on the original December 2020 guidance by incorporating recent treatment efficacy data, addressing public comments, and outlining persisting data gaps.? In the document, USEPA prioritizes ongoing research to achieve efficient PFAS destruction and minimize environmental release.

Despite over three years of additional data, a definitive solution for PFAS waste management remains elusive. The 2024 Guidance evaluates three existing technologies (incineration, landfilling, and deep-well injection) and suggests interim storage with controls may be warranted for site-specific considerations rather than use of any of these three existing technologies. It also introduces information on four promising, but not yet commercially available emerging destructive technologies (mechanochemical degradation, electrochemical oxidation, gasification and pyrolysis, and supercritical water oxidation).?

While the 2024 Guidance does not endorse any specific approach, it does outline a methodical process for assessing disposal and destruction options by providing a framework for case-by-case technology evaluation, considering efficacy, available analytical methods, field screening, and impacts on vulnerable communities.? The USEPA emphasizes selecting technologies that minimize risk to human health and the environment.? Additionally, by identifying key data gaps, USEPA sets the stage for future research, essential given the anticipated volume of PFAS-contaminated waste needing management.?

MALCOLM – Can you place the compass image and do a text wrap somewhere within this section?

Scanning the Open Seas: The Broader PFAS Perspective

There are other state and federal regulatory initiatives making headway beyond those already discussed.? For example, in January of this year, the USEPA released three analytical methods to better measure PFAS in environmental samples.? Perhaps the most significant is the finalization of Method 1633 for PFAS analysis in non-drinking water samples.? Method 1633 is applicable for wastewater, groundwater, surface water, biosolids, soils, and other matrices and will be the go-to method for most compliance sampling purposes.? In tandem with Method 1633, USEPA finalized Method 1621 for adsorbable organic fluorine (AOF) in aqueous matrices allowing for broad screening of thousands of PFAS compounds.? Additionally, draft Method OTM-50 for analysis of PFAS in air from stationary sources was released in January marking a significant step towards regulating PFAS in air emissions and better understanding incomplete combustion byproducts from thermal destruction technologies.

Furthermore, in November 2023, USEPA incorporated a new Toxic Substance Control Act (TSCA) provision requiring commercial entities that have manufactured or imported chemical substances and mixtures that contain PFAS compounds, including as byproducts or impurities, to submit one-time reports of their products retroactive to 2011.? The TSCA reporting requirement is intended to characterize sources, quantities, and types of PFAS compounds used in the country and represents a significant regulatory obligation to the business community, including many entities previously unaffected by TSCA regulations.? The reporting window opens in November 2024 and closes in May 2025.

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Throughout 2024, we will be tracking rule development on other regulatory fronts as well, such as potential for hazardous waste designation proposals under RCRA. Stay tuned for more insights as we continue to navigate the evolving realm of PFAS in our future PFAS Perspectives series.?

Contact Info:

Kyle McDonald, CES, Project Scientist, Trihydro Corporation

Fritz Krembs, P.E., P.G., Engineering Specialist, Trihydro Corporation