SUPPLEMENTARY INFORMATION: ( printed page 29426)

Table of Contents

I. General Information

A. What is the EPA proposing?

B. Does this action apply to me?

II. Background

A. PFAS

B. PFAS Regulatory History

C. What are the 2024 PFAS NPDWR requirements related to PFOA and PFOS?

D. Why is the EPA proposing to provide more time for systems to achieve the MCL compliance deadlines for PFOA and PFOS?

E. Why is the EPA not proposing to provide more time for systems to achieve the MCL compliance deadlines for other contaminants covered by the 2024 PFAS NPDWR?

III. National Exemptions Framework

A. Exempting Public Water Systems From the PFOA and PFOS MCL Compliance Dates Under SDWA 1416

B. Statutory Authority

C. SDWA 1416 Evaluation and Proposed Findings

1. Water System Exemption Eligibility

2. Proposal To Grant Water System Exemptions

D. National Exemptions Framework Implementation and Primacy Considerations

1. PFOA and PFOS Federal Exemptions Process and Requirements

a. Exemptions Process and Timing

b. PFOA and PFOS Exemption Requirements

i. PFOA and PFOS Reduction Control Measures

ii. Public Notification Requirements

iii. Consumer Confidence Report Requirements

2. Primacy Considerations

IV. Economic Analysis

A. Baseline

B. Economic Analysis for the Proposed Rule

V. Public Participation

A. Request for Comment on the Proposed Rule

B. Written Comments

C. Participation in Virtual Public Hearing

VI. Statutory and Executive Orders Reviews

A. Executive Order 12866: Regulatory Planning and Review and Executive Order 13563: Improving Regulation and Regulatory Review

B. Executive Order 14192: Unleashing Prosperity Through Deregulation

C. Paperwork Reduction Act (PRA)

D. Regulatory Flexibility Act (RFA)

E. Unfunded Mandates Reform Act (UMRA)

F. Executive Order 13132: Federalism

G. Executive Order 13175: Consultation and Coordination With Indian Tribal Governments

H. Executive Order 13045: Protection of Children From Environmental Health & Safety Risks

I. Executive Order 13211: Actions That Significantly Affect Energy Supply, Distribution, or Use

J. National Technology Transfer and Advancement Act (NTTAA)

K. Consultations With the National Drinking Water Advisory Council (NDWAC)

VII. References

I. General Information

A. What is the EPA proposing?

The EPA proposes a federal exemption pursuant to SDWA 1416, including 1416(f) and 1450(a)(1), that would extend the compliance deadlines for the MCLs for PFOA and PFOS from April 26, 2029, to April 26, 2031, for systems that apply (see section III of this preamble for additional details). The Agency welcomes public comment to inform how the EPA proceeds with finalizing the proposal.

B. Does this action apply to me?

Entities potentially affected by this action include those that are subject to the 2024 Per- and Polyfluoroalkyl Substances (PFAS) National Primary Drinking Water Regulation (NPDWR), namely public water systems (PWSs) and those state and Tribal agencies responsible for drinking water regulatory development and enforcement. These PWSs include community water systems (CWSs) and non-transient non-community water systems (NTNCWSs). 89 FR 32532, April 26, 2024. A PWS, as defined in 40 CFR 141.2, provides water to the public “for human consumption through pipes or . . . other constructed conveyances, if such system has at least fifteen service connections or regularly serves an average of at least twenty-five individuals daily at least 60 days out of the year.” See also SDWA 1401(4)(A). A PWS is either a CWS or a non-community water system (NCWS). A CWS, as defined in 40 CFR 141.2, is “a public water system which serves at least 15 service connections used by year-round residents or regularly serves at least 25 year-round residents.” A NTNCWS is a type of NCWS, and the definition in 40 CFR 141.2 for a NTNCWS is “a public water system that is not a [CWS] and that regularly serves at least 25 of the same persons over 6 months per year.” The following table provides examples of the regulated entities under this rulemaking:

This table is not intended to be exhaustive but rather provides a guide for readers regarding entities likely to be regulated by the proposed rule. This table includes the types of entities that the EPA is now aware could potentially be regulated by this rulemaking. To determine whether your entity is regulated by this rulemaking, this notice of proposed rulemaking should be carefully examined. If you have questions regarding the applicability of this rulemaking to a particular entity, consult the person listed in the FOR FURTHER INFORMATION CONTACT section.

II. Background

A. PFAS

PFAS are a large class of thousands of synthetic chemicals that have been in use in the United States and around the world since the 1940s (USEPA, 2024a). The unique properties of PFAS, including thermal- and chemical-stability and the ability to repel water and stains, are pertinent to a variety of commercial, industrial, and consumer products (USEPA, 2024a). PFAS generally break down slowly due to their strong carbon-fluorine bonds, which contribute to their environmental persistence (USEPA, 2024b). Exposure to certain PFAS, including PFOA and PFOS, can lead to accumulation in tissues, including the liver and kidneys, and blood (ATSDR, 2021; Domingo and Nadal, 2019; Fromme et al., 2009; USEPA, 2024c; USEPA, 2024d). Humans can be exposed to PFAS, including PFOA and PFOS, via ingestion of contaminated food and drinking water, inhalation, and dermal contact. A wide range of consumer products contain PFOA and PFOS, and exposures can occur outdoors and indoors, including occupational settings, among other routes (ITRC, 2023; USEPA, 2024a). Some population groups may be more sensitive to the harmful health effects of certain PFAS include pregnant and lactating woman, children, and infants. Studies indicate that PFOA and PFOS exposure above ( printed page 29427) certain levels may result in adverse health effects, including developmental effects to fetuses during pregnancy or to breast- or formula-fed infants, cancers, immunological effects, cardiovascular effects, and liver damage, among others (USEPA, 2024c, USEPA, 2024d, ATSDR, 2021; USEPA, 2021a; USEPA, 2021b).

This proposal applies to two specific PFAS: PFOA and PFOS. The manufacturing and use of these compounds have largely been voluntarily phased out in the United States; however, small quantities of PFOA may still be produced, imported, and used by some companies, and limited uses of PFOS are ongoing (ITRC, 2023). Due to their use, persistence and physicochemical properties, these compounds are known to be present across different environmental media and existing evidence demonstrates multiple pathways for human exposure (NCSL, 2025; USEPA, 2024a; USEPA, 2024b). Additionally, other PFAS precursors degrade to PFOA and/or PFOS in the environment, further contributing to their persistence and exposure risk (Buck et al., 2011; Conder et al., 2008; Liu and Mejia Avendaño, 2013).

B. PFAS Regulatory History

SDWA 1412(b)(1)(B)(i) requires the EPA to publish a Contaminant Candidate List (CCL) every five years. The CCL is a list of contaminants that are known or anticipated to occur in PWSs, are not currently subject to any proposed or promulgated NPDWRs, and that may require future regulation under SDWA. By listing contaminants on the CCL, the EPA may obtain data to better understand their potential occurrence and health impacts, although this listing does not itself impose requirements on PWSs. The EPA listed PFOS and PFOA on the 2009 and 2016 CCLs to identify these contaminants as a priority for regulatory decision making (USEPA, 2009; USEPA, 2016).

The EPA uses the Unregulated Contaminant Monitoring Rule (UCMR) to collect data for contaminants that are anticipated to be present in drinking water and do not have regulations under SDWA. Under the UCMR, PWSs are required to monitor for priority unregulated contaminants every five years, and the Agency makes the results publicly available. As part of the third and fifth UCMR (UCMR 3 and UCMR 5, respectively), water systems collected monitoring data for PFAS, including PFOA and PFOS (USEPA, 2012; USEPA, 2021c).

On February 20, 2020, the EPA made preliminary determinations to regulate PFOA and PFOS. The EPA then made final positive regulatory determinations to regulate PFOA and PFOS in March 2021 (USEPA, 2021d). On March 29, 2023, the EPA proposed an NPDWR for PFOA and PFOS (USEPA, 2023a). On April 26, 2024, the EPA finalized an NPDWR for PFOA and PFOS (USEPA, 2024b).

C. What are the 2024 PFAS NPDWR requirements related to PFOA and PFOS?

The 2024 PFAS NPDWR established Maximum Contaminant Level Goals (MCLGs) for PFOA and PFOS at zero (0) and MCLs at 4.0 nanograms per liter or parts per trillion (ng/L or ppt) for both compounds (40 CFR 141.50(a)(24) and (25); 40 CFR 141.61(c)(2)(vi) and (c)(2)(vii)). The 2024 PFAS NPDWR listed feasible treatment technologies for PWSs that can be used to comply with those MCLs (40 CFR 141.61(d) and (e)).

The EPA also finalized public “Right-to-Know” provisions in the 2024 PFAS NPDWR, which include public notification (PN) and Consumer Confidence Report (CCR) requirements (see 40 CFR part 141 subparts O and Q). CWSs are required to prepare and deliver to its customers an annual CCR that reports detectable levels of PFOA and PFOS and provides health effects language in the case of MCL violations (40 CFR 141.151(a) and (d)). Additionally, MCL violations require Tier 2 PN, or notification provided as soon as practicable but no later than 30 days after a system learns of an MCL violation (40 CFR 141.203). Additionally, violations related to monitoring and testing procedures ( e.g., a system failing to monitor) require Tier 3 PN, or notice no later than one year after a system learns of the violation (40 CFR 141.204).

To demonstrate compliance with the MCLs, the EPA also finalized monitoring and reporting requirements for PWSs (40 CFR 141.902 and 141.904). PWSs are required to sample each entry point using a monitoring regime based on the EPA's Standard Monitoring Framework for Synthetic Organic Contaminants (SOCs). As part of these requirements, PWSs must complete their initial monitoring, which may include the use of recent, previously acquired monitoring to satisfy some or all of the initial monitoring requirements by April 26, 2027 (40 CFR 141.900(b)(2); 40 CFR 141.902(b)(1)(xi)). To demonstrate that finished drinking water does not exceed the MCLs for PFOA and PFOS, PWSs are required under the 2024 PFAS NPDWR to conduct compliance monitoring for PFOA and PFOS at a frequency based on these sample results. PWSs are required to report to primacy agencies the results of all initial and compliance monitoring results to ensure compliance with the 2024 PFAS NPDWR.

Under the 2024 PFAS NPDWR, the EPA exercised its authority under SDWA 1412(b)(10) to allow a two-year nationwide capital improvement extension to comply with the MCLs. All systems are required to comply with the MCLs by April 26, 2029 (40 CFR 141.900(b)(4); 40 CFR 141.903).

D. Why is the EPA proposing to provide more time for systems to achieve the MCL compliance deadlines for PFOA and PFOS?

The EPA is proposing to exempt eligible systems from the 2024 NPDWR PFOA and PFOS MCL compliance deadlines, and instead extend these deadlines to provide greater regulatory flexibility and support for addressing these PFAS in drinking water, all while prioritizing both short-term and long-term public health protection. In evaluating the need for these extensions, the Agency considered compounding implementation challenges facing PWSs, including in small, rural, and disadvantaged communities, and other factors that may ease the implementation burden for many systems, and the communities they serve, if they had more time to comply. These include: the time it takes to implement capital improvement projects; certified operator availability to build and operate treatment systems; financial limitations, including the time it takes to determine and secure funding to construct capital improvements; availability of monitoring data to inform capital improvement decisions; broader strategies to address PFAS, such as source water protection, PFAS treatment technology improvements and innovation; and the ability for the EPA to provide a broader number of systems with technical assistance to support rule compliance.

E. Why is the EPA not proposing to provide more time for systems to achieve the MCL compliance deadlines for other contaminants covered by the 2024 PFAS NPDWR?

In a separate action, the EPA is proposing to rescind the MCLs and associated provisions for perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), hexafluoropropylene oxide dimer acid (HFPO-DA) and the Hazard Index that includes these PFAS and perfluorobutane sulfonic acid (PFBS). Accordingly, this proposal only applies to two specific PFAS: PFOA and PFOS. ( printed page 29428)

III. National Exemptions Framework

A. Exempting Public Water Systems From the PFOA and PFOS MCL Compliance Dates Under SDWA 1416

Since promulgation of the 2024 PFAS NPDWR, the EPA has become aware that many systems may be unable to comply with the MCLs by the current 2029 compliance date and may seek the EPA's approval of an exemption pursuant to SDWA 1416(f) before states have obtained primacy. Considering that similar circumstances are currently impacting the majority of systems seeking to achieve MCL compliance, to streamline the exemptions process and manage the potentially large number of exemption requests, the EPA proposes a national rule to govern the process for systems to request and obtain a two-year federal exemption from compliance with the PFOA and PFOS MCLs in states, territories, and Tribes that have not obtained primacy for those MCLs. An exemption under SDWA 1416 is an appropriate mechanism to provide this additional time to systems that meet the statutory criteria for an exemption. Exemptions can help ensure that systems which are unable to comply with the PFOA and PFOS MCLs by the compliance date will have the opportunity to obtain the technical and financial resources necessary to take the steps needed to comply with the rule “as expeditiously as practicable” but not later than three years after the otherwise applicable compliance date (SDWA 1416(b)(2)(A)). Although the statute allows up to three years, this proposed federal exemption will provide an appropriate federally-implemented bridge for systems to come into compliance as “expeditiously as practicable” while states adopt and begin implementation of the rule. See section III.C of this preamble for more on the EPA's findings. Once states have obtained primacy, they can determine whether to provide additional exemptions, consistent with SDWA 1416(a) and (b), if individual water systems are still unable to comply by the federally extended compliance date.

B. Statutory Authority

SDWA 1416(a) and (b) authorizes states with primary enforcement authority to exempt any system that meets specified criteria in SDWA 1416(a) from any requirement respecting any MCL or treatment technique (TT) requirement of an applicable NPDWR. If a state grants an exemption, it must prescribe a schedule for compliance not to exceed three years and may include a schedule for the implementation of control measures, after providing notice and an opportunity for a public hearing on the schedule. SDWA 1416(f) provides that if a state does not have primacy, the Administrator has the same authority to exempt a PWS from any MCL or TT requirement of an applicable NPDWR “under the same conditions and in the same manner” as a state would be authorized to grant exemptions if it had primacy. Additionally, SDWA 1450(a)(1) provides that the Administrator is authorized to prescribe such regulations as are necessary or appropriate to carry out their functions under this title.

While section 1416 has typically been used to authorize exemptions by primacy agencies on a case-by-case basis, nothing in the statute expressly forecloses a more streamlined exemption-by-rule approach, just as permitting requirements under other programs often provide for both individual permits and permits-by-rule. Because it is possible that there will be a large number of requests for additional time for compliance with the PFOA and PFOS MCLs before states obtain primacy, a national rule to streamline the statutory process for providing additional time is appropriate.

The EPA recognizes that the exemption process under SDWA section 1416 requires a number of findings before authorizing additional time for compliance, some of which are amenable to a categorical approach and some of which are not. As a result, the EPA has designed this proposed exemption-by-rule process to provide categorical findings (see section III.C of this preamble), where possible, but also to require water systems to individually request the exemption by providing system-specific information to the EPA in order for the exemption to apply on a case-by-case basis. This combination of categorical findings and system-specific application both meets the statutory requirements for exemption eligibility under SDWA section 1416 and streamlines the process for issuing exemptions to the extent possible. The EPA is seeking public comment on this proposed national framework and the Agency's use of authority under SDWA 1416 in this streamlined fashion.

C. SDWA 1416 Evaluation and Proposed Findings

In accordance with the EPA's authority to grant exemptions under SDWA 1416(f) and to prescribe such regulations as are necessary or appropriate to carry out this authority as provided under SDWA 1450(a)(1), in this rulemaking the EPA proposes an “exemption by rule” for systems in states that have not obtained primacy for 40 CFR part 141 subpart Z under which eligible systems may individually request, submit system-specific information, and obtain a two-year federal exemption from the requirements related to these MCLs until April 26, 2031. As described in section III.B of this preamble, SDWA 1416(f) provides that the Administrator has the same authority to exempt a PWS from any MCL or TT requirement of an applicable NPDWR “under the same conditions and in the same manner” described in SDWA 1416(a) and (b) as a state would be authorized to grant exemptions if it had primacy.

1. Water System Exemption Eligibility

As required under SDWA 1416(a), a water system may be exempt from the requirements of an MCL upon a finding that: (1) Due to compelling factors (which may include economic factors, including qualification of the PWS as a system serving a disadvantaged community pursuant to SDWA 1452(d)), the PWS is unable to comply with such contaminant level or TT requirement, or to implement measures to develop an alternative source of water supply; (2) The PWS was in operation on the effective date of such contaminant level or TT requirement, or, for a system that was not in operation by that date, only if no reasonable alternative source of drinking water is available to such new system; (3) The granting of the exemption will not result in an unreasonable risk to health (URTH); and (4) Management or restructuring changes (or both) cannot reasonably be made that will result in compliance with this title or, if compliance cannot be achieved, improve the quality of the drinking water. For water systems subject to the rule requirements, the EPA evaluated these criteria and proposes to find pursuant to 40 CFR 142.58(a) that any PWS is eligible for the two-year federal PFOA and PFOS MCLs exemption from April 26, 2029 until April 26, 2031 if it meets the proposed information requirements in 40 CFR 142.58(b), is located in a state, territory, or Tribe that does not have primacy for 40 CFR part 141 subpart Z, was in operation on or prior to June 25, 2024, and does not have a variance from the requirements of the PFOA and PFOS MCLs.

Unable To Comply With the PFOA and PFOS MCLs Due to Compelling Factors

Through the inclusion of SDWA 1416 exemption provisions, Congress recognized that PWSs may not be able to achieve compliance with the MCLs by the dates prescribed under SDWA 1412(b)(10). Exemptions provide ( printed page 29429) systems that are unable to comply due to compelling factors more time to achieve compliance, including small and rural systems that might experience particular hardship due to economies of scale and technical expertise challenges. In the Agency's evaluation of the first statutory exemption eligibility criterion, regardless of system size and location, the EPA evaluated new information available since the 2024 PFAS NPDWR and considered several compelling factors, including those related to economic, technical, and logistical limitations and proposes that collectively they support a finding that some water systems that exceed the PFOA and PFOS MCLs may be unable to comply with those MCLs by the current compliance date of April 26, 2029.

The first compelling factor that the EPA evaluated relates to capital improvements for implementing the PFOA and PFOS MCLs. In the 2024 NPDWR, the EPA determined that there are multiple Best Available Technologies (BATs) for PFOA and PFOS that are listed in table 1 to paragraph (a) of 40 CFR 142.62 (USEPA, 2024e); these technologies continue to currently be widely available. Though the EPA does not require treatment technology or any specific action to achieve MCL compliance, and a very small subset of systems may select non-treatment options, the EPA anticipates the majority of systems that will be required to take action to address levels of PFOA and PFOS exceeding the MCLs will need to make capital improvements and install one of these BATs. Both as part of the 2024 PFAS NPDWR and in accordance with 40 CFR 142.5 for this proposed rulemaking, the EPA considered the types of capital improvement activities that could reasonably be undertaken and the time necessary to conduct these activities, consistent with financial consequences to ratepayers, in order to choose and implement one of the PFAS removal BATs. Moreover, in the promulgation of the 2024 PFAS NPDWR, the EPA's evaluation of these capital improvement activities led to a determination that a two-year capital improvement extension, the allowable time provided under SDWA 1412(b)(10), was necessary for water systems to achieve MCL compliance given the information available at that time. Since promulgation of that rule, the EPA has further assessed current circumstances and has found that, in addition to factors that have become evident since the promulgation of the 2024 PFAS NPDWR, many of the capital improvement considerations justifying allowing the additional two years under SDWA 1412(b)(10) are still significant issues for water systems; therefore, there are compelling reasons why some water systems will need additional time for MCL compliance under SDWA 1416(f) exemption authority. Specifically, the record since the 2024 PFAS NPDWR includes current evidence of escalating construction and equipment costs in the intervening years. According to the U.S. Bureau of Labor Statistics (USBLS), inflation in construction materials for PWS equipment increased by over 20 percent between 2024 and 2025 alone (USBLS, 2025). There is also new evidence of ongoing volatility in global steel markets that may create procurement uncertainty and affect the timely ability of water systems to maintain and upgrade treatment facilities to comply with the PFOA and PFOS MCLs (NUCA, 2025; Reuters, 2025). Additionally, supply chain disruptions continue to delay procurement of specialized filtration media for PFAS treatment technologies which leads to longer-than-anticipated development times and higher-than-expected capital cost increases (AWWA, 2025).

Another compelling factor shown by new information available since the 2024 PFAS NPDWR is workforce challenges, specifically related to having a sufficient number of qualified personnel necessary to operate the advanced treatment facilities that remove PFAS in drinking water (AWWA, 2025; NRWA, 2024; USGAO, 2024). The EPA acknowledges that though there are overall workforce issues in the drinking water treatment sector beyond those specific to PFAS, this is only further exacerbated by the need for operators with higher-level qualifications. Without these more advanced operators, even if water systems are able to plan and install the PFAS removal treatment technologies, they may not have an adequate workforce to actually operate the new systems. Moreover, the American Water Works Association's (AWWA's) 2025 State of the Industry Report highlights the critical challenges associated with the water workforce, including retirements, recruitment and retainment difficulties, and specialized skill needs, such as those needed for treating PFAS (AWWA, 2025). Without additional time through the federal exemptions, some systems that exceed the PFOA and PFOS MCLs are unlikely to be able to secure the necessary skilled personnel or enhance the expertise of existing operators by the current compliance date for the PFOA and PFOS MCLs.

Financial limitations are also a compelling factor that many water systems face in achieving MCL compliance. Regulation of PFOA and PFOS in PWSs is estimated to result in significant health benefits, however, the costs, which are likely to be ultimately born by the ratepayers for these systems, are considerable. According to the AWWA's 2025 State of the Water Industry Report, financing of capital improvements for both essential upgrades and new treatment technologies, such as those used for treating PFAS, is the greatest challenge identified by water systems of all sizes. Additionally, less than half of the water systems surveyed in AWWA's 2025 Report are confident in their ability to fund the costs through rates and fees and stated that determining how to fund these improvements will require identifying and evaluating the full range of funding sources while balancing the costs to customers (AWWA, 2025). Therefore, though many water systems are able to fully meet the requirements of the rule, some water systems may face financial hardship and economic challenges and other compelling circumstances in the short-term, making them unable to comply with the regulation by the current compliance date.

The EPA also evaluated a number of other considerations that, when combined with the previously discussed capital improvement, workforce challenges, and financial hardship, are likely to significantly influence water systems' ability to comply with the MCLs by 2029. Moreover, when collectively considering the cumulative effects of these compelling factors and other considerations, water systems are much more likely to effectively and successfully implement and maintain compliance with the PFOA and PFOS MCLs when granted additional time provided through the federal exemptions.

First, exemptions would allow systems more time and flexibility to determine and comprehensively evaluate all of their financial assistance and funding options for capital improvements, making the most cost-effective decisions for their customers and water system financial sustainability. This time will be particularly beneficial for small, rural and disadvantaged systems with less expertise in undertaking these activities. Specific to supporting water systems with these activities, exemptions would also allow the EPA to offer assistance through the Agency's PFAS OUTreach ( printed page 29430) (PFAS OUT) and Tackling Emerging Contaminants (TEC) Real Water Technical Assistance (RealWaterTA) initiatives to a much greater number of systems needing financial and technical aid to achieve compliance with the PFOA and PFOS MCLs. The EPA's PFAS OUT initiative specifically supports communities in addressing PFAS and will continue to work directly with water systems by connecting them with the available funding, tools, and technical assistance opportunities to facilitate capital improvements and comply with the drinking water standards. Furthermore, additional time would allow for state-offered technical assistance or the EPA's TEC RealWaterTA initiative to directly impact more communities. The RealWaterTA initiative aims to further the administration of the noncompetitive Emerging Contaminants in Small or Disadvantaged Communities grant (EC-SDC) by helping small or disadvantaged communities assess and address emerging contaminants and PFAS in their drinking water, connect to federal funding through the Infrastructure Investment and Jobs Act (IIJA), evaluate engineering alternatives, and comply with the PFOA and PFOS MCLs (USEPA, 2026). Systems will also benefit in their ability to achieve compliance from other EPA RealWaterTA offerings, such as Water Engineering Support. With more time provided through these exemptions, a greater number of water systems would realize the benefits of these EPA programs, offsetting the resources they would have previously needed to independently utilize in determining this information.

Another consideration related to the EPA's proposed two-year exemption by rule is treatment technology improvements and innovation after the promulgation of the 2024 PFAS NPDWR, including the current and future availability of more cost-effective PFAS removal technologies. By allowing more time through the exemptions, the EPA expects that emerging technologies not previously designated as BATs will become better understood and may become more widely available. Some of these emerging technologies have been demonstrated at the bench-scale but have not yet been proven at the full scale or are not yet commercially available (AWWA, 2023), while others have been, or are currently being, demonstrated at the full scale and providing more time will facilitate the identification of performance gaps so they can be better implemented. Examples of these promising technologies may include alternative sorbents and exchange media, separation methods such as foam fractionation, and innovative destructive technologies. Advances may also occur in managing treatment residuals (USEPA, 2024b).

Powdered activated carbon (PAC) is another non-BAT technology that has been shown in bench- and pilot-scale testing to be able to effectively remove some PFAS, specifically long chain PFAS such as PFOA and PFOS (up to >99 percent removal) (USEPA, 2023b). Use of this technology may be more cost-efficient for certain systems, particularly in the short-term, as it does not require upfront infrastructure costs and can be integrated into the existing treatment system (Kentucky Energy and Environment Cabinet, 2025). The effectiveness of PAC for PFAS treatment is dependent on case-by-case scenarios at individual PWSs, since percent removal depends on many factors such as PAC dosage, PAC particle size, contact time, and influent water organic carbon (USEPA, 2023b). However, if a water system already has PAC installed for other purposes such as taste and odor, the system may be able to enhance its PAC dose to easily and rapidly reduce PFOA and PFOS concentrations (Nakazawa et al., 2023; Alameddine et al., 2025). In addition, PAC may be particularly effective for systems that require modest percent removals due to marginal MCL exceedances (Crone et al., 2019; USEPA, 2018), and, given that the current results of the UCMR 5 demonstrate that approximately 15 to 20 percent of UCMR 5 systems are exceeding the PFOA and/or PFOS MCLs at levels slightly higher than the MCLs, these systems and other non-UCMR systems with similar levels may specifically benefit from additional time as this alternative technology continues to be investigated for full-scale performance effectiveness and becomes more widely implemented.

Similarly, at the time of the 2024 PFAS NPDWR promulgation in April 2024, the EPA provided that the NSF/American National Standards Institute (NSF/ANSI) standard for PFOA and PFOS removal in point-of-use and point-of-entry (POU and POE) devices did not meet the PFOA and PFOS MCLs set through the 2024 PFAS NPDWR. However, the EPA also stated in the 2024 PFAS NPDWR that it anticipates that POU and POE devices will eventually comply with the MCLs (USEPA, 2024b). Though the NSF/ANSI standard is not yet revised to assure the POE and POU certified devices will consistently reduce PFOA and PFOS levels to below the MCLs, the EPA is aware that the NSF/ANSI Drinking Water Treatment Unit Joint Committee Task Group is currently continuing the process to update their standards to align with the 2024 PFAS NPDWR (NSF, 2024). Therefore, the EPA continues to reasonably expect that allowing more time for MCL compliance through exemptions will result in greater flexibility and the availability of POU and POE devices as both an additional and lower-cost compliance option, specifically for very small water systems and certain NTNCWS such as schools, factories, office buildings, and hospitals that provide their own water. These cost savings could be substantial, with the EPA estimating that the annual cost savings per household for POU treatment instead of centralized granular activated carbon (GAC) treatment for systems serving 500 or fewer, which account for over 60 percent of all water systems subject to the rule requirements, would be a minimum of 40 percent to as much as a 72 percent savings (USEPA, 2024f).

The EPA also considered the availability of initial monitoring data for PFOA and PFOS, which all systems are required to collect by April 2027 under the requirements of the 2024 PFAS NPDWR and will be used to make informed decisions on treatment needs for many PWSs across the country. This includes data collected under UCMR 5, which requires all PWSs serving 3,300 or more people, and a representative sample of smaller systems, to monitor for 29 PFAS, including PFOA and PFOS. Sampling under UCMR 5 concluded in December 2025, with the final dataset available in 2026 (USEPA, 2021c). Systems with previously acquired data through state or other appropriate monitoring, and those that have participated in UCMR 5, are expected to have reduced initial monitoring costs as these systems may use these monitoring results to support implementation of monitoring requirements of the 2024 PFAS NPDWR in accordance with 40 CFR 141.902(b)(1)(vi).

Having access to their initial monitoring data will allow many utilities to have a complete understanding of PFOA and PFOS occurrence in their systems and whether capital improvements are necessary to comply with the MCLs. For systems that will need to make capital improvements, their full individual system results, once collected, will provide systems with information to determine the most efficient technology solution and secure capital improvement funding which can take a ( printed page 29431) significant amount of time. Moreover, once this funding is secured, additional time to actually implement the capital improvement steps and achieve MCL compliance will be necessary. Thus, the PFOA and PFOS exemptions would allow for more initial monitoring data to be collected, including the complete UCMR 5 dataset to be available, allowing water systems to use this data in making the most fully informed and cost-efficient decisions regarding PFOA and PFOS treatment needs tailored to local water quality conditions.

An additional consideration the EPA evaluated relates to the broader strategies announced by the EPA to protect drinking water sources from PFAS before entering PWSs (USEPA, 2025a; USEPA, 2025b). The EPA has announced the development of effluent limitations guidelines (ELGs) for certain PFAS that will help stop PFAS from entering drinking water systems and hold facilities that are discharging these contaminants into surface water accountable. By stopping PFAS from entering source waters, the forthcoming ELGs are expected to minimize the occurrence of PFAS in drinking water sources, as well as other environment matrices, thereby reducing the cost burden for downstream water systems and the cost-of-living for community members served by those systems (USEPA, 2025a; USEPA, 2025b). The additional time for these efforts to be implemented may allow for any decreases in contamination to be realized in response to these source reduction efforts and may ultimately preclude the need for installing costly treatment technologies or impact decisions on the water systems' most effective treatment technology selection.

In this proposed rulemaking, the EPA proposes to find that some PWSs that exceed the MCLs under 40 CFR part 141 subpart Z may be impacted by one or more of the compelling factors identified earlier in this section and, as a result will be unable to comply with the PFOA and PFOS MCLs by April 26, 2029. Under this proposal, any such system must submit a statement that it cannot comply with the PFOA and PFOS MCLs due to compelling factors. For any water systems requesting the two-year federal exemption, the proposed rule requires the submission of such statement in 40 CFR 142.58(b). The EPA requests comment on this proposed finding, as well as these and other compelling factors, and supporting information the Agency should consider in taking final action on this proposal.

Public Water System in Operation on Date of Rule Promulgation or New System Has No Reasonable Alternative

The second statutory exemption eligibility criterion for systems requires that a PWS be in operation on the effective date of the maximum contaminant level ( i.e., June 25, 2024) or, if it was not in operation at that time, has no reasonable alternative source of drinking water. As part of the 2024 PFAS NPDWR, the EPA determined that approximately 66,000 PWSs would be subject to the rule requirements (USEPA, 2024b; USEPA, 2024e). All of these systems meet SDWA 1416(a)(2) exemption eligibility criterion because they were in operation at that time. Systems seeking the two-year federal exemption under this proposed rulemaking would be required to provide the EPA with the date of their initial system operations pursuant to 40 CFR 142.58(b). Systems that initiated operations following June 25, 2024, would not be eligible for a federal exemption under this rule without demonstrating that no reasonable alternative source of drinking water is available to the system. An exemption may be available to such a system under the existing regulations for case-by-case exemptions issued by the EPA (see 40 CFR 142.50 through 142.57).

Unreasonable Risk to Health (URTH)

The third statutory exemption eligibility criterion requires that the granting of the exemption will not result in an URTH. Based on Congress including exemption provisions in SDWA with the clear intention that they be used to address systems that may need additional time to achieve compliance, Congress necessarily contemplated that the customers of these systems would be exposed to drinking water above the MCL for the period of the exemption and there would be some risk to health present. The limitation that Congress imposed on this excess exposure is that it will not constitute an “unreasonable” risk to health. SDWA provides no definition of an URTH; nor does it prescribe criteria for making this determination. In contrast, the statute expressly defines health-based MCLGs and feasibility-based MCLs. In particular, an MCLG is defined explicitly as “the maximum level of a contaminant in drinking water at which no known or anticipated adverse health effects would occur, allowing for an adequate margin of safety” which is the same as a no risk level. Therefore, Congress has left to the EPA's judgment the determination of what factors to consider and the determination of how much risk above the MCLs and MCLGs is “unreasonable” for the exemption time period.

While a two-year exemption from the PFOA and PFOS MCLs poses a risk to health, the EPA proposes that, for purposes of implementing SDWA 1416 exemption provisions, this risk is not “unreasonable” for systems with concentrations below 12 ppt for both PFOA and PFOS. However, the EPA notes that this should not create a presumption that concentrations greater than this do or would result in an URTH. In accordance, the EPA seeks comment on whether the risk to human health that may occur due to this amount of exposure (12 ppt) to a previously unregulated contaminant, over a limited period of time, is unreasonable. This concentration is within the average range of current state PFOA and PFOS standards (USEPA, 2024e). Additionally, this level would have the ancillary benefit of assisting in the identification of the highest risk systems, and the communities they serve, to prioritize implementing long-term compliance actions. In this proposed rulemaking, the EPA is requesting comment on the proposal to use this level in assessing whether there is an URTH and any other levels the Agency should consider when evaluating SDWA 1416(a)(3) exemption criteria.

For systems seeking an exemption with any most recent PFOA and PFOS sampling result(s) at or above 12 ppt, the EPA proposes to find that a two-year exemption would not present an URTH if, as a condition of the exemption, these systems would have to implement interim control measures during the two-year exemption period to mitigate the additional health risks that may occur as a result of the exemption. These measures, pursuant to 40 CFR 142.59, are intended to reduce and provide information on PFAS exposures for consumers of these water systems. Proposed control measures include installation, operation, and maintenance of POU and/or POE devices, providing alternative water sources, making water filtration pitchers available, implementing source water controls, providing public education materials on reducing PFAS from various sources including drinking water, and conducting community outreach activities. Please see section III.D.1.b.i of this preamble for more information on these proposed control measure actions and exemption requirements. The EPA acknowledges that these mitigation actions may not reduce PFOA and PFOS to either the MCLs or below 12 ppt; however, the EPA expects they can ( printed page 29432) significantly reduce concentrations of these and other PFAS in drinking water and inform consumers of steps they can take to reduce PFOA and PFOS exposures from drinking water and other sources of PFAS. Furthermore, these interim control measures are only intended to improve public health protection during the brief two-year exemption period so that the exemption would not result in an URTH while water systems work towards implementation of compliance technologies or other non-treatment compliance strategies to ensure compliance with the PFOA and PFOS MCLs by the end of the proposed exemption period (April 26, 2031).

Under SDWA, as well as the proposed national exemptions rulemaking, an “unreasonable risk” determination applies only to PWSs in the context of evaluating SDWA 1416(a) criteria and their ability to achieve compliance with NPDWRs. The EPA acknowledges that there are risks to human health due to PFOA and PFOS and that holding polluters accountable is a priority. In an April 2024 announcement, the EPA emphasized that it is taking action to “hold polluters accountable” and to “establish a clear liability framework that ensures the polluter pays and passive receivers are protected” (USEPA, 2025b). Accordingly, the EPA announced in May 2024, “Drinking water systems are passive receivers of PFOA and PFOS. Polluters can contaminate the surface waters or aquifers that these systems rely on to provide the drinking water to their communities” (USEPA, 2025a), and the EPA intends to continue to use its regulatory and enforcement tools to hold polluters accountable. Wherever feasible, and particularly in cases where a polluter who caused PFAS contamination can be readily identified, the EPA intends to reduce costs to PWSs by making those responsible for PFAS contamination bear the burden of cleanup, and as needed, provide alternate water to communities, rather than shifting that responsibility to the communities that rely on those systems. The “unreasonable risk” standard under SDWA 1416 governs whether allowing additional time for PWSs to come into compliance will ensure that persons served by PWSs facing risks from ongoing contamination will not be “unreasonably” burdened in light of the costs and feasibilities associated with compliance by water systems with a new drinking water standard. It is not a standard relevant to ensuring that polluters are held accountable or otherwise liable for past or ongoing contamination under enforcement authorities.

Of note, the “unreasonable risk” finding under SDWA 1416 differs fundamentally from a potential “substantial endangerment” finding under SDWA 1431. An “unreasonable risk” in the context of determining whether a water system may qualify for an exemption from compliance under SDWA 1416 assumes a level of risk to the persons served by the PWS but balances that risk with other factors such as feasibility of treatment, cost, and timeline, so that the risk associated with a compliance delay is not deemed unreasonable over the time-limited exemption period. By contrast, SDWA 1431 authority does not require any findings regarding cost or feasibility. Thus, any regulatory interpretation of “unreasonable risk” under SDWA 1416 is limited to PWSs seeking compliance exemptions and is irrelevant to actions already taken or to be taken under potential substantial endangerment findings, including those against polluters. Therefore, this proposed action, including the proposed finding that mitigation measures are not necessary for a two-year exemption to meet the statutory requirement that “granting of the exemption will not result in an unreasonable risk to health” if PFOA and PFOS concentrations are below 12 ppt, does not apply to any PFAS releases or to any EPA enforcement actions taken in the past, nor does it limit any actions the EPA may take against those entities in the future. Indeed, if the Agency finds that contamination within the exemption timeframe may present an imminent or substantial endangerment to immediate and/or long-term health, the EPA does have authority to act as “deem[ed] necessary in order to protect the health of such persons” under SDWA 1431(a). As previously requested, the Agency welcomes public comment on the proposed URTH finding when evaluating SDWA 1416(a)(3) exemption criteria, and whether the risk to human health that may occur due to exposure to PFOA or PFOS at levels less than 12 ppt, over a limited period of time, is unreasonable.

Management and Restructuring

The fourth statutory exemption eligibility criterion under SDWA 1416(a)(4) requires that management and restructuring changes (or both) cannot reasonably be made by the water system that will result in compliance with the MCL or, if compliance cannot be achieved, improve the quality of the drinking water. In evaluating this statutory exemption eligibility criterion, in accordance with 40 CFR 142.20(b)(1)(i), the EPA considered the following measures: (1) Consideration of rate increases, accounting changes, the appointment of a state-certified operator under the State's Operator Certification program, and contractual agreements for joint operation with one or more PWSs; (2) Activities consistent with the State's Capacity Development Strategy to help the PWS acquire and maintain technical, financial, and managerial capacity to come into compliance with the Act; and (3) Ownership changes, physical consolidation with another PWS, or other feasible and appropriate means of consolidation which would result in compliance with the Act.

As described earlier in this section, the EPA forecasts that the large majority of all systems exceeding the PFOA and/or PFOS MCLs will install advanced treatment technologies in order to come into compliance. Therefore, for most systems unable to comply, implementing management and restructuring changes will not be sufficient to result in compliance with the MCLs. Additionally, as previously stated and discussed in the 2024 PFAS NPDWR preamble, the process for new installation of advanced PFAS drinking water treatment technologies, including the procurement, planning, construction, and piloting activities that must be undertaken, takes several years to be completed in the most cost-effective and efficient manner. The EPA proposes to find that, for some water systems that exceed the MCLs, management and restructuring changes supporting the ability of the system to install and use advanced treatment, such as rate increases and new system operators and owners, cannot reasonably be made in time to result in compliance with the MCLs by the current compliance date. Similarly, the state capacity development programs, that small and disadvantaged systems frequently participate in, also can take several years to effect significant results and would not be able to reasonably impact compliance with the MCLs.

To achieve compliance with the PFOA and PFOS MCLs, the EPA anticipates that some water systems will seek to restructure, such as entering into water system partnerships or physically consolidating or connecting with another nearby water system. Though these types of actions and agreements are feasible, they can take many years to be implemented, often involving major infrastructure projects to interconnect, intergovernmental and other business agreements, financing steps, and community engagement activities (California State Water Resources ( printed page 29433) Control Board, 2024). Moreover, as a result of this complex process, this will be a more viable and carefully implemented option for water systems granted additional time under the federal exemption.

Pursuant to 40 CFR 142.20(b)(1)(i), the EPA also considered the availability of Drinking Water State Revolving Fund (DWSRF) assistance and other federal and state programs that are reasonably likely to be available within the period of the exemption to implement the measures discussed previously associated with management and restructuring changes and to support compliance with the PFOA and PFOS MCLs. Funding mechanisms provided to states help offset costs borne by ratepayers when systems are forced to adopt more advanced technologies to address emerging contaminants. The EPA finds that in accordance with the regulation, funding for capital improvement projects and other rule compliance activities is likely to be available within the period of the exemption. The EPA notes that funding is also likely to be available prior to the period of the exemption which will support activities and projects continuing to be undertaken within the period of the exemption. More specifically, IIJA funds currently available include billions of dollars to specifically support addressing emerging contaminants, like PFAS, in drinking water, particularly the installation of capital improvements such as treatment facilities. Though the EPA recognizes these funds are already appropriated and will be allotted to states prior to the period of the exemption, given the lengthy time associated with the overall capital improvements process, the use of the funds and the infrastructure projects and activities the funds support is expected to continue to be undertaken during the period of the exemption. Moreover, allotted funds that are not used by a state will be reallotted to eligible states over subsequent years that align with the exemption period. In the case of IIJA funds appropriated for emerging contaminants such as PFAS, this means that additional funding will flow to states with demonstrated need for emerging contaminant funding. For other federal funding sources likely to be available within the period of the exemption, such as those non-IIJA funds available through the DWSRF, EPA grants, and the United States Department of Agriculture (USDA) Rural Development funding program, though the EPA is unable to confirm the future amounts of these other funding sources during the period of the exemption, based on past availability, the EPA anticipates there are likely to be additional available funds during the period of the exemption. The EPA further notes that there have been billions of dollars made available to water systems as part of finalized private liability settlement agreements with PFAS dischargers (USDCSC, 2025). These funds, as well as any others from future settlement agreements, may also be available during the period of the exemption. Therefore, the EPA expects there will be available funding within and prior to the period of the exemption, and the exemptions will support the time necessary for systems to determine and obtain these funds in the best way to lessen financial impacts on their consumers and align with their capital improvement plans and state priorities.

2. Proposal To Grant Water System Exemptions

SDWA 1416(b)(2)(B) states that no exemption shall be granted unless the PWS establishes that they are taking all practicable steps to meet the MCL. It also provides that the system must demonstrate at least one of the following three criteria: (1) The system cannot meet the standard without capital improvements which cannot be completed prior to the date established pursuant to SDWA 1412(b)(10); (2) In the case of a system which needs financial assistance for the necessary improvement, the system has entered into an agreement to obtain such financial assistance or assistance pursuant to SDWA 1452, or any other federal or state program is reasonably likely to be available during the period of the exemption; or (3) The system has entered into an enforceable agreement to become part of a regional water system.

As described in section III.C.1 of this preamble, the EPA expects that nearly all water systems exceeding the PFOA and PFOS MCLs will need to make capital improvements to achieve compliance with the standard and, due to compelling factors and other considerations detailed previously, many of these systems will not be able to make these improvements prior to April 26, 2029. According to AWWA's 2025 State of the Industry Report, numerous water systems will need financial assistance to make these improvements (AWWA, 2025). The EPA proposes to find that federal or state funding programs, such as the DWSRF, EPA grant programs, and USDA Rural Development, are reasonably likely to be available for those water systems in need of financial assistance during the period of the exemption, including a significant amount of IIJA funding that is both currently and anticipated to be available prior to the exemption period for the capital improvement projects being undertaken during the exemption period. Therefore, based upon some systems not being able to fully make capital improvements prior to April 26, 2029, the likelihood that many systems that exceed the MCLs will need financial assistance in order to make the required capital improvements, and the known and expected availability of federal and state funding to support rule compliance, under this proposal, a water system that exceeds the PFOA or PFOS MCLs and provides the EPA with the required information under 40 CFR 142.58(b) will meet SDWA 1416(b)(2)(B) criteria and will qualify for the federal exemption.

D. National Exemptions Framework Implementation and Primacy Considerations

Under the proposed national exemption framework and process, all systems without a variance from the PFOA and PFOS MCL requirements, those in operation on or before June 24, 2024, and those located in states that do not have primacy for the PFOA and PFOS MCLs are eligible for the two-year exemption upon submission of a request documenting its qualification for the exemption to the EPA. To request the federal exemption, the proposed rule requires a water system to directly notify the EPA that it is seeking an exemption and provide the Agency with information according to the proposed requirements of 40 CFR 142.58(b) by November 16, 2026. The EPA proposes that the exemption would be granted by operation of the rule if the water system meets the proposed requirements and unless the exemption is terminated by the EPA upon a finding that the system has failed to comply with the requirements of the exemption. For systems granted the exemption, PFOA and PFOS MCL compliance must be achieved by April 26, 2031.

1. PFOA and PFOS Federal Exemptions Process and Requirements

a. Exemptions Process and Timing

As discussed in section III.C.1 of this preamble and in accordance with 40 CFR 142.58(a), the EPA proposes that all water systems within states that do not have primacy for 40 CFR part 141 subpart Z, were in operation as of June 25, 2024, and do not have a variance from the PFOA and PFOS MCL requirements and that meet the other criteria in the rule are eligible for a ( printed page 29434) federal PFOA and PFOS MCL exemption from April 26, 2029 through April 26, 2031. Per 40 CFR 142.58(a), any eligible water system will be exempt from the PFOA and PFOS MCL requirements upon providing the EPA with required information under 40 CFR 142.58(b) including: (1) Water system information ( i.e., Public Water System Identification Number [PWSID], water system name, contact information, and, if defined as a wholesale system according to 40 CFR 141.2, a list of all consecutive system(s) through which water is distributed, or if defined as a consecutive system according to 40 CFR 141.2, a list of the wholesale system(s) providing finished water); (2) Initial date of system operations; (3) A statement that the system cannot comply with the PFOA and PFOS MCLs by April 26, 2029, due to economic or other compelling factors, that an alternative water source is not available to meet the PFOA and PFOS MCLs, and the system cannot reasonably make management changes or restructure to meet the requirements of the rule; (4) A statement that the system is taking all practicable steps to meet the standard. The statement must also include that the system cannot meet the standard without capital improvements which cannot be completed prior to April 26, 2029; or, in the case of a system that needs financial assistance for necessary improvements, that the system has entered into an agreement to obtain such financial assistance (or assistance pursuant to SDWA 1452) or any other federal or state program is reasonably likely to be available during the period of the exemption; or the system has entered into an enforceable agreement to become part of a regional PWS; (5) Most recent sample result(s) for PFOA and PFOS; and (6) For water systems with any PFOA or PFOS results equal to or exceeding 12 ppt, selection of and certification that at least two interim control measures described in section III.D.1.b.i of this preamble and in 40 CFR 142.59 will be implemented during the exemption period to ensure no URTH. Water systems will be required to submit this information to the EPA no later than 180 days following rule promulgation.^[1] The EPA will provide details on the process for submitting information concurrent with final rule promulgation.

In accordance with 40 CFR 142.58(c), only those eligible water systems submitting an exemption request and required information under 40 CFR 142.58(b) would be exempt from PFOA and PFOS MCL requirements. The EPA proposes that an exemption for a water system may be terminated if the system fails to comply with the requirements or conditions of the exemption, including implementation of control measures required for applicable water systems prescribed under 40 CFR 142.59 and detailed in section III.D.1.b.i of this preamble. For all systems that are covered by the federal exemption, the EPA proposes (per 40 CFR 141.58(c)(2)) that the schedule for compliance to meet the PFOA and PFOS MCLs is April 26, 2031. As discussed earlier in this section, the EPA's proposed finding that the exemption would not result in an URTH is based, in part, on the limited effect of a two-year exemption. For all systems without an exemption, MCL compliance is required by April 26, 2029, pursuant to 40 CFR 141.900(b)(4). Water systems that seek to obtain additional exemptions beyond the two-year federal exemption period may request their primacy agency to grant an exemption for up to one additional year under the provisions of SDWA 1416(a). Further, in accordance with SDWA 1416(b)(2)(C), for smaller water systems (those serving ≤3,300 population) that need financial assistance for necessary improvements, primacy agencies may grant renewals of the exemption not to exceed six more years to achieve compliance with the PFOA and PFOS MCLs.

b. PFOA and PFOS Exemption Requirements

i. PFOA and PFOS Reduction Control Measures

SDWA 1416(a)(3) requires that the granting of an exemption will not result in an URTH. As described in section III.C.1 of this preamble, to evaluate this requirement and ensure that the exemption will not result in an URTH, the EPA proposes that systems with any measured result(s) for PFOA or PFOS equal to or greater than 12 ppt must implement PFOA and PFOS reduction control measures in order to be covered by the exemption.

The EPA proposes six control measure options that applicable water systems could select and implement to reduce PFOA and PFOS concentrations and provide information for consumers to decrease their exposure to PFAS. Control measures are not required to reduce concentrations to levels as low as the MCLs or achieve MCL compliance, rather they are intended to temporarily decrease concentrations of PFOA and PFOS and associated exposure during the period of the exemption until longer term and more effective solutions can be implemented to achieve MCL compliance. In accordance with 40 CFR 142.59, these measures include providing water pitchers and filters certified to reduce PFOA and PFOS concentrations, delivering alternative water supplies with lower levels of PFOA and PFOS, installing, operating, and maintaining POU or POE devices certified to decrease PFOA and PFOS concentrations, implementing actions and plans to decrease PFOA and PFOS levels in sources of drinking water, distributing written public education materials to consumers on PFOA and PFOS exposure sources, and conducting community educational outreach activities on PFOA and PFOS in drinking water. The EPA proposes to require water systems with any PFOA or PFOS result(s) greater than or equal to 12 ppt to select and implement at least two of these control measures during the period of the exemption from April 26, 2029, through April 26, 2031, and make each of the two control measures a water system selects available for all customers. Additionally, the EPA proposes that the two control measures selected cannot solely include public education materials and public outreach activities. In determining which control measures to implement, water systems should seek to implement those with the greatest public health protection based on their site-specific conditions. The EPA is requesting comment on these six control measures and if there are other measures the Agency should consider.

Water Filtration Pitchers

The EPA proposes pitcher filters as a short-term control measure option to reduce PFOA and PFOS. For the purposes of 40 CFR part 142 subpart F, the EPA proposes to define a pitcher filter under 40 CFR 142.2 as a non-plumbed filtration device, which consists of a gravity fed water filtration cartridge and a filtered drinking water reservoir, that is certified by an ANSI accredited certifier to reduce PFAS in drinking water. Pitcher filters are not considered POU or POE devices, which are defined in 40 CFR 141.2. Though there are currently no pitcher filters certified to reduce PFOA and PFOS to the MCLs; there are approximately 20 pitcher devices that have been certified by an ANSI accredited certifying ( printed page 29435) organization to meet either the current (2022) or previous ANSI/NSF 53 standard, which require these devices to demonstrate a reduction of PFOA and PFOS concentrations to at least 20 or 70 ppt, respectively. Some of the accredited certifying organizations as well as pitcher device companies have also stated that the devices can achieve reduction to levels below 20 ppt (WQA, 2023; USEPA, 2024g; 4Patriots, 2024). Moreover, the 2022 total PFAS reduction ANSI/NSF 53 standard sets a combined limit of 20 ppt for seven PFAS, including PFOA and PFOS. Therefore, it is reasonable to assume PFOA and PFOS concentrations in filtered water will be below 20 ppt considering the other five PFAS as part of the combined limit. The EPA is also allowing the use of pitcher filters that have been certified under the older NSF/ANSI standard requiring PFOA and PFOS to 70 ppt. The EPA believes that even for these filters, the majority will reduce concentrations to below 20 ppt in most cases. This is because pitcher filters have been found to be generally effective in removing PFOA and PFOS, often with removal efficiencies greater than 50 percent and as high as 99+ percent in some cases (Herkert et al., 2020; Mulhern et al., 2021; Teymoorian et al., 2024; and Zarębska et al., 2025). Based on the EPA's 2024 occurrence analyses supporting the Economic Analysis (EA), and the UCMR 5 data reported through October 2025, the vast majority of PWS samples exceeding 4.0 ppt are below 40 ppt.^[2] Hence, even a pitcher filter with only 50 percent average removal efficiency will reduce water consumed to below 20 ppt in most cases. For modelling purposes, the EPA is assuming that filters reduce PFOA and PFOS to 20 ppt.

Additionally, as noted in section III.C.1 of this preamble, NSF/ANSI is currently continuing the process to update their standards to align with the 2024 PFAS NPDWR (NSF, 2024); thus, the EPA anticipates that at the time of the exemption period, devices will likely be able to achieve PFOA and PFOS reduction to levels as low as the PFOA and PFOS MCLs. For systems that elect to implement pitcher filters as a control measure, in accordance with 40 CFR 142.59(c) any devices must be certified by an ANSI accredited certifier to meet the ANSI/NSF standard (currently ANSI/NSF standard 53). Additionally, water systems will be required to provide pitcher devices, two years of replacement filters, and instructions for their use and maintenance to consumers served by the system upon request and make these available at all drinking water tap locations in NTNCWSs.

Alternative Water Supplies

Another option for systems required to implement control measures is the provision of alternative water supplies. Alternative water supplies may include temporarily switching to a new source with lower levels of PFOA and PFOS or blending of water supplies to reduce PFOA and PFOS concentrations where the source change would not be a change that could “reasonably be made that will result in compliance.” For example, water systems could take these actions to temporarily reduce PFOA and PFOS to lower levels, but it would not achieve lower levels required for long-term MCL compliance. Alternative water supplies may also include the distribution of bottled water. For systems electing to utilize bottled water as a condition of the PFOA and PFOS exemption, the PWS must follow the requirements prescribed in 40 CFR 142.62(g). In summary, this includes either: (1) developing a monitoring program for bottled water, with reasonable assurances that it meets all MCLs; or, (2) obtaining certification from the bottled water company that the product has been taken from an approved source (as defined in 21 CFR 129.3(a)), the bottled water company has conducted monitoring (in accordance with 21 CFR 129.80(g)(1) through (3)), and the bottled water does not exceed other MCLs. Additionally, the water system is responsible for delivering a sufficient amount of bottled water to every person supplied by the water system.

Point-of-Use and Point-of-Entry Devices

A third option the EPA proposes for water systems to choose as a condition of the exemption is the installation and maintenance of POU or POE devices to reduce PFOA and PFOS concentrations in drinking water. In accordance with 40 CFR 141.2, POE devices are treatment devices applied to the drinking water entering a house or building to reduce contaminants in the drinking water distributed throughout the house or building. A POU device is defined in 40 CFR 141.2 as a water treatment device physically installed or connected to a single fixture, outlet, or tap to reduce or remove contaminants in drinking water.

As discussed in section III.C.1 of this preamble, the NSF/ANSI standard for PFOA and PFOS removal in POU and POE devices does not currently meet the PFOA and PFOS MCLs. However, for the purposes of these PFOA and PFOS exemptions, there are numerous POU and POE devices that have been certified to meet the ANSI/NSF 53/58 standards and reduce PFOA and PFOS concentrations in drinking water to 20 or 70 ppt. Additionally, several of the POU and POE providers or accredited certifying organizations have stated that the devices can achieve PFOA and PFOS reduction lower than 20 ppt (WQA, 2023; USEPA, 2024g). Similar to water pitcher filters discussed earlier in this section, the EPA expects that filters can reduce to levels below 20 ppt during much of their use and also, that during the exemption period, devices will likely be able to achieve PFOA and PFOS reduction to levels as low as the PFOA and PFOS MCLs (NSF, 2024). Accordingly, use of these devices will likely reduce concentrations of PFOA and PFOS in drinking water and associated exposures to consumers during the period of the exemption.

For systems that elect to implement POU or POE devices as one of the control measures, the EPA proposes to apply the requirement of 40 CFR 142.62(h) that any device chosen must be certified by an ANSI accredited certifier to meet the ANSI/NSF standard. PWSs must also meet the requirements of 40 CFR 142.62(h). To summarize, these requirements include: (1) the PWS must operate and maintain the POU and/or POE treatment system; (2) prior to POU and/or POE device installation, the PWS must have an approved monitoring plan to ensure public health protection equivalent to that provided by central water treatment; (3) the PWS must apply effective technology under an approved plan and the microbiological safety of the water must be continuously maintained; (4) certification of performance, field testing, and, if not already included in the certification process, an engineering design review of the POU or POE devices; (5) the design and application of the POU or POE devices must consider the potential for increasing concentrations of heterotrophic bacteria in water treated with activated carbon; and (6) buildings connected to the system also have sufficient POU or POE devices that are properly installed, maintained, and monitored such that all consumers will be protected. The EPA is seeking comment on whether it should not apply some or all of these requirements to POU and POE devices selected as one of the control measures to establish that ( printed page 29436) the exemption will not result in an URTH.

Source Water Controls

Determining the cause(s) of contaminants and reducing their concentrations in sources of drinking water can be more cost-effective and sustainable than installing treatment technologies and continuously treating contaminated drinking water. The EPA has many resources and funding programs that can assist drinking water systems in conducting and updating Source Water Assessments (SWAs) and planning and implementing investigations of PFAS contamination sources during the exemption period. These include the EPA's Drinking Water Mapping Application to Protect Source Water (DWMAPS), the EPA's Funding Integration Tool for Source Water (FITS), EC-SDC grant program, and the EPA's RealWaterTA program described previously in section III.C.1 of this preamble. There may also be resources available at the state level to support these types of source water assessment and funding activities addressing sources of PFAS.

The EPA's DWMAPS can be utilized to help investigate known or potential sources of PFAS contamination (USEPA, 2025c). Specifically, DWMAPS is an online mapping tool that drinking water utilities can employ to update SWAs and protection plans. SWAs involve compiling an inventory of existing/potential sources of contamination within a system's source water area, determining the susceptibility of the system to contamination, determining where source water controls may be necessary, and distributing the results to the local stakeholders for further action (USEPA, 2025d). Although continuous updating of a SWA is not required, some water systems voluntarily update or evaluate their assessment through actions such as delineating their source water protection area with updated geospatial data and utilizing advanced hydrological and hydrogeologic fate and transport models and new data on emerging contaminants (URI, 2022; USEPA, 2025e).

Federal funding for initiatives that protect source water can be identified by using the EPA's FITS tool (USEPA, 2025f). For more information on FITS and examples of previously funded projects, visit https://www.epa.gov/​sourcewaterprotection/​fits. This funding may support measures such as projects that trap or treat contaminated water before reaching source water, develop maps or models that display PFAS concentrations, and PFAS monitoring training and equipment, for example. Water systems can also contact Source Water Protection Coordinators at the EPA Regional Offices to get more information and connect with funding programs (USEPA, 2025g).

Additionally, drinking water systems are often passive receivers of contaminants discharged by facilities upstream of the water system and can have little control of the quality of their source waters. As discussed in section III.C.1 of this preamble, the EPA is exploring and has announced regulatory strategies, such as ELGs, to protect drinking water sources from PFAS and hold polluters accountable for PFAS contamination. States may also set discharge limits through other regulatory mechanisms, including National Pollutant Discharge Elimination System (NPDES) permits.

Therefore, the EPA proposes that another option water systems may choose as a control measure is to develop actions to reduce PFOA and PFOS in the sources of drinking water. For systems that elect source water controls as a control measure, in accordance with 40 CFR 142.59(d) as proposed, the water system would need to certify one of the following requirements: (1) A direct agreement with an entity directly discharging PFOA and PFOS into the drinking water systems' source water(s) that establishes reduction of the PFOA and PFOS discharges; (2) Source water(s) of the system are subject to the regulations that reduce PFOA and PFOS discharges in the source water(s); (3) A source water assessment to identify and address known and potential non-point and point sources of PFOA and PFOS; or (4) Funding or technical assistance to implement source water assessment planning or activities focused on addressing and reducing PFOA and PFOS.

Public Education Materials

Public education of the sources and exposure pathways for PFOA and PFOS is a very important component of reducing risk by increasing consumer awareness of the potential health impacts and steps consumers can take to reduce these impacts. While these materials will not directly reduce PFOA and PFOS in drinking water in the same manner as some of the other proposed control measures ( i.e., pitcher filters, POU and POE devices), providing consumers information will allow them to better understand what PFAS (including PFOA and PFOS) are and possible exposure from drinking water, as well as other potentially significant sources of exposure. Moreover, with this information, consumers can decrease their overall exposure to PFOA and PFOS both during and beyond the exemption period.

As proposed, PWSs selecting written public education materials as a control measure would be required to ensure the materials include, at a minimum, content covering the following: (1) general explanation of PFAS, including PFOA and PFOS; (2) health effects of PFAS, particularly PFOA and PFOS and including specific information for pregnant people, infants and children that may be impacted during critical life stages; (3) possible sources of PFAS, including PFOA and PFOS, including drinking water, consumer products, environmental and occupational factors, proximity to commercial and industrial sites, among others; (4) consumer steps to reduce PFOA and PFOS exposure from drinking water and other sources of PFAS; (5) analytical results for PFOA and PFOS in the systems' drinking water; and (6) actions the water system is taking to address PFOA and PFOS, and any other PFAS, in drinking water. If the EPA finalizes this requirement, the EPA intends to develop guidance and example public education materials that water systems may use to meet this requirement.

To streamline the process for materials distribution, the EPA proposes that these materials are provided to water system customers concurrent with the delivery and timing requirements for CCRs (40 CFR 141.152) and PNs (40 CFR 141.204(b)(1)). This would include annually or biannually in CCRs, depending on population served by the water system, and annually (for all water system sizes) as part of Tier 3 PN (which may be provided in a CCR pursuant to 40 CFR 141.204(b)(2)). Additionally, to better ensure consumers that may be at greater risk of exposure during the exemption period, including pregnant people and those in critical life stages, are made aware of this educational information, the EPA is also proposing that the materials must be provided to relevant organizations within the water system's service area. Relevant organizations include local public health agencies, Women, Infant, and Children (WIC) and Head Start Programs, public and private hospitals and medical clinics, pediatricians, and obstetricians, gynecologists and midwives.

Community Outreach Activities

Similar to written public education materials, public outreach activities are a key mechanism for informing consumers about PFOA and PFOS in drinking water and other sources of ( printed page 29437) PFAS. Moreover, these types of activities allow the water system to directly communicate with their consumers and provide information on the actions the system is taking to address PFOA and PFOS in drinking water. Additionally, like written public education materials, these activities are not explicitly reducing PFOA and PFOS in drinking water compared to other proposed control measures; however, it will allow consumers greater awareness about their potential exposure and more information to make better-informed choices related to their total PFAS exposure.

For systems that elect to conduct community outreach activities as a control measure, the EPA proposes that the activities must include a discussion of PFOA and PFOS sampling results at the water system, short-term mitigation steps the system is taking to reduce PFOA and PFOS in drinking water, long-term actions the system is taking to achieve PFOA and PFOS MCL compliance, steps consumers can take to reduce PFOA and PFOS exposure from drinking water and other sources of PFAS, and information on how to obtain a pitcher filter certified to reduce PFOA and PFOS in drinking water as discussed earlier in this section and required under 40 CFR 142.59(c). The types of community outreach activities the water system can choose to conduct include public meetings, participation in community events, contacting customers directly via phone, text, email or door hanger, or social media campaigns. Water systems must conduct at least two of these activities within six months following the beginning of the exemption period ( i.e., by October 26, 2029) and every six months until the end of the exemption period ( i.e., April 26, 2031).

ii. Public Notification Requirements

As part of SDWA and in accordance with the requirements of 40 CFR part 141 subpart Q, the PN Rule establishes requirements that PWSs must follow regarding the form, manner, frequency, and content of a public notice. The requirement to provide PN under certain specified circumstances is an integral part of the public health protection and consumer Right-to-Know provisions of SDWA. Owners and operators of PWSs are required to notify persons served when they fail to comply with the requirements of the NPDWR; have a variance or exemption from the drinking water regulations; or are facing other situations posing a risk to public health. Under the PN Rule, the notification requirements are based on the tier to which a violation or situation is assigned. The EPA specifies three categories, or tiers, of PN requirements, to account for the seriousness of the violation or situation and any potential adverse health effects that may occur.

The PN Rule specifies the NPDWR violations and other situations that require the water systems to provide public notice, including if a system is operating under an exemption issued under SDWA 1416 or a system fails to comply with the requirements of any schedule that has been set under an exemption (table 1 to 40 CFR 141.201, appendix A to 40 CFR part 141 subpart Q). Systems operating under an exemption granted under SDWA 1416, 40 CFR 141.204(a)(3) and (b)(1) require that Tier 3 PN be issued not later than one year after the water system begins operating under the exemption. Following the initial notice, the water system must then repeat the notice annually for as long as the exemption continues. The proposed rule does not treat a federal PFOA and PFOS exemption differently for tiering purposes, consistent with existing PN Rule requirements. The EPA requests comment on whether it should require a Tier 2 notice for systems operating under an exemption of the PFOA and PFOS MCLs and require systems to provide the notice within 30 days of beginning to operate under the exemption.

Public notices for systems operating under an exemption must include specific information required by 40 CFR 141.205(b)(1) including: (1) An explanation of the reasons for the exemption; (2) The date on which the exemption was issued; (3) A brief status report on the steps the system is taking to install treatment, find alternative sources of water, or otherwise comply with the terms and schedules of the exemption; and (4) A notice of any opportunity for public input in the review, or renewal, of the exemption. This information is required to be included in an initial public notice of the PFOA and PFOS exemption issued no later than April 26, 2030, and repeated annually for the period of the exemption. Additionally, for systems required to implement control measures, a status update on those measures must be included according to 40 CFR 141.205(b)(1)(iii). The EPA requests comment on additional content requirements for the Tier 3 PN of PFOA and PFOS exemptions.

When a water system fails to comply with the terms and conditions of an existing exemption, 40 CFR 141.203(a) and (b)(1) require that Tier 2 PN be issued as soon as practicable, but no later than 30 days after the system learns of the violation. As required by 40 CFR 141.205(b)(2), public notices of an exemption violation must contain information according to 40 CFR 141.205(a).

iii. Consumer Confidence Report Requirements

CWSs must prepare and deliver to its customers a CCR annually or biannually (beginning January 1, 2027, for systems serving populations of 10,000 or greater) in accordance with requirements in 40 CFR part 141 subpart O. CCRs provide customers with information about their local drinking water quality as well as information regarding the water system's compliance with drinking water regulations. If a system is operating under the terms of an exemption issued under SDWA 1416, as required by 40 CFR 141.153(c)(2) and (g), the report must include the definition “Variances and Exemptions: State or EPA permission not to meet an MCL or a treatment technique under certain conditions”, and contain the following information: (1) An explanation of the reasons for the exemption; (2) The date on which the exemption was issued; (3) A brief status report on the steps the system is taking to install treatment, find alternative sources of water, or otherwise comply with the terms and schedules of the exemption; and (4) A notice of any opportunity for public input in the review, or renewal, of the exemption. For CWSs that choose to opt-in to the proposed PFOA and PFOS exemptions, this information would be required to be included in CCRs between April 26, 2029, and April 26, 2031. Additionally, for systems required to implement proposed control measures under 40 CFR 142.59, a status update on those measures must be included according to 40 CFR 141.153(g)(3).

2. Primacy Considerations

As discussed in section III.B of this preamble, SDWA 1416(f) authorizes the EPA Administrator to exempt PWSs from MCL requirements if the state, Tribe, or territory (collectively referred to as “state” for the purposes of this section) does not have primacy for the new or revised NPDWR. To facilitate a streamlined approach for PFOA and PFOS MCL exemptions and to reduce the burden on primacy agencies, the EPA is proposing this national exemption framework that would allow the Agency to provide MCL exemptions to PWSs during the time period prior to when a state obtains primacy.

Once a state obtains primacy for the 2024 PFAS NPDWR, the EPA will no longer be authorized to issue MCL ( printed page 29438) exemptions for PWSs in that state. Therefore, if the EPA finalizes and issues the proposed MCL exemptions before a state obtains primacy, and the state wishes to continue the federal exemptions after gaining primacy, then those primacy agencies must incorporate the EPA-issued exemptions into their adopted state regulations and primacy applications. States may also decide not to allow the federal exemptions to continue after obtaining primacy, as states can choose to be more stringent. As such, the EPA encourages states to notify their water systems whether they plan to allow the proposed federal exemptions to continue after gaining primacy for the 2024 PFAS NPDWR. Additionally, some state laws may prohibit exemptions from drinking water requirements for PWSs; in those states, the EPA's proposed exemptions would have no effect, regardless of whether the state has primacy. Further, a state does not need to have primacy for the Variance and Exemption regulation (40 CFR part 142 subpart C) to continue to allow the proposed federal MCL exemptions for PFOA and PFOS.

IV. Economic Analysis

This section summarizes the Economic Analysis (EA) supporting document (USEPA, 2025h) for this proposed rulemaking. The EA presented here, and in the EA supporting document (USEPA, 2025h), fulfills the Executive Order 12866: Regulatory Planning and Review requirements to estimate the potential costs and benefits associated with this action.

The EPA largely relied on the EA conducted for the 2024 PFAS NPDWR which is described in the Federal Register for the 2024 PFAS NPDWR (USEPA, 2024b), and the Economic Analysis for the Final Per- and Polyfluoroalkyl Substances National Primary Drinking Water Regulation (USEPA, 2024e) and Appendices (USEPA, 2024h). For the estimation of quantified benefits and costs, the EPA utilized a variant of its SafeWater modeling platform, the SafeWater Multi-Contaminant Benefit-Cost (MCBC) model.^[3]

A. Baseline

In its Guidelines for Preparing Economic Analyses, the EPA characterizes the baseline as a reference point that reflects the world without the regulation (USEPA, 2024i); this baseline is the starting point for estimating the potential incremental benefits and costs of this proposed rule. For this rulemaking, the Agency selected as the baseline the previously analyzed, Option 1a, found in the Federal Register for the 2024 PFAS NPDWR finalized in April 2024 because this action solely focuses on the MCLs for PFOA and PFOS (USEPA, 2024b).^[4]

For detailed information on the data and assumptions used to develop the baseline (Option 1a in the 2024 PFAS NPDWR), see the Economic Analysis for the Final Per- and Polyfluoroalkyl Substances National Primary Drinking Water Regulation (USEPA, 2024e) and Appendices (USEPA, 2024h). The EPA made the following adjustments to the 2024 analysis of Option 1a to facilitate its use as the baseline: (1) the Agency updated the dollar year for all monetized values from the 2022 dollars used in the 2024 PFAS NPDWR analysis to 2024 dollars using the gross domestic product (GDP) implicit price deflator,^[5] and (2) the EPA added two additional years to the period of analysis, resulting in a total of 84 periods, mirroring the two-year exemption to the compliance schedule under this proposal. As explained earlier in this section, the EPA is using the estimated total benefits and costs of Option 1a to characterize the baseline as this action solely focuses on the MCLs for PFOA and PFOS. The baseline total benefits and costs will be subtracted from the estimated total benefits and costs for this proposed rule to determine the incremental impact of moving from the baseline to SDWA 1416 revised 2024 PFAS NPDWR. The updated baseline monetized annualized benefits and costs are shown in Exhibit IV-1 of this preamble. Note these values are discounted at both 3 percent and 7 percent.^[6] In addition to the summary exhibit presented here, see Table 3-3 in the Economic Analysis for the Proposed Rule Extending the Compliance Date for the PFOA and PFOS Maximum Contaminant Levels (USEPA, 2025h) for the undiscounted and discounted (both 3 percent and 7 percent) estimated baseline benefits and costs for each of the 84 years in the period of analysis.

The annualized quantified national expected value baseline cost is $1,626 million (in 2024 dollars discounted at 3 percent) and $1,636.6 million (in 2024 dollars discounted at 7 percent). These estimates represent costs for both the PWS and primacy agency. The annualized baseline quantified benefit estimate is $1,478.8 million at a 3 percent discount rate and $968.6 million at a 7 percent discount rate. These quantified benefits reflect the avoided future adverse health outcomes attributable to PFOA and PFOS reductions and co-removal of additional ( printed page 29439) disinfection byproduct (DBP) contaminants due to actions undertaken to comply with the MCLs for PFOA and PFOS. The quantified benefits are estimated using a cost-of-illness approach. In the national analysis, the EPA quantified three PFOA and PFOS related health endpoints: changes in birth weight, cardiovascular disease, and kidney cancer (renal cell carcinoma). The Agency's quantified values also represent reductions in cases of bladder cancer associated with reductions in DBPs which result from PFOA and PFOS treatment.

The quantified baseline results in Exhibit IV-1 of this preamble are not representative of all benefits and costs anticipated under the baseline. Due to occurrence, health, and economic data limitations, there are several adverse health effects associated with PFOA and PFOS (and other co-occurring PFAS) exposure and costs associated with treatment that the EPA could not estimate quantitatively. As part of the 2024 PFAS rulemaking, the EPA qualitatively discussed additional adverse health effects, including reproductive effects, such as decreased fertility; increased high blood pressure in pregnant women; developmental effects or delays in children, including accelerated puberty, bone variations, or behavioral changes; increased risk of some cancers, including prostate, kidney, and testicular cancers; reduced ability of the body's immune system to fight infections, including reduced vaccine response; interference with the body's natural hormones; and increased cholesterol levels and/or risk of obesity. With regard to non-quantified costs, baseline cost estimates may be underestimated because the EPA could not estimate the impact of the co-occurrence of other non-regulated PFAS and contaminants that would reduce the useful life of the filter media used for GAC and/or ion exchange treatment. In addition, the EPA could not estimate the degree to which PWSs required to treat would in the future decide to handle the spent filtration media as hazardous waste.^[7]

B. Economic Analysis for the Proposed Rule

The annualized cost and benefit estimates described in the baseline represent a stream of values which occur over the 84-year period of analysis used for the assessment of the regulatory impacts. This rule proposes to use SDWA 1416 authority to allow all water systems to opt into a federal exemption by rule that would allow systems to delay compliance with the PFOA and PFOS MCLs of 4.0 ppt for two years. In addition, this rule would require systems with PFOA or PFOS monitoring data at or above 12 ppt to implement two of the regulatorily identified control measures ^[8] during the period of the exemption (effectively periods 7 and 8 of the periods of analysis, or the two years from April 2029 to April 203(1). In the EPA's benefit-cost model, both the costs of treating for PFOA and/or PFOS at PWS entry points which exceed the MCLs, as well as the resultant benefits, measured as a reduction in medical costs from fewer negative health outcomes, are pushed out two years. The “time value of money” can be understood as the perceived value of a dollar decreasing as the length of time one must wait to receive that money increases, given potential inflation and opportunity costs. When considering the timing of cost outlays and calculating the present value of a stream of impacts made into the future, which have been estimated in constant year dollars, the “time value of money” is accounted for by reducing, or discounting, the estimated future payments so they represent the current value of a dollar. Similarly, benefit receipts in the future have a lower value to people than current benefits because of the “time value of money.” Because the proposed rule treatment costs and benefits accrue two years in the future, these costs and benefits must be discounted two additional years which results in a decrease in the net present value and annualized costs and benefits of the proposed rule. Specifically, this time value differential is accounted for in the analysis by the application of the 3 percent and 7 percent discount rates to the stream of estimated undiscounted costs and benefits.

In the analysis of this proposed rule, all 2024 PFAS NPDWR Option 1a regulatory requirements remain the same except for the shift in the MCL compliance date. Therefore, the time profile for the costs associated with initial administration of the rule, and sampling and report costs remain the same. Only the cost associated with the installation and operation of the PFAS treatment technology are delayed by two years resulting in a reduction in its net present value, which in turn reduces the estimated annualized cost for this proposed rulemaking. Likewise, because the estimated benefits from PFOA and PFOS reductions are dependent on the timing of treatment, all benefits under this proposed rule are shifted into the future by two years resulting in a lower net present value and lower annualized benefits estimates. The EPA also assumes that all systems exceeding either the MCL for PFOA or PFOS will opt into the proposed exemption process. The two-year shift in compliance produced by the proposed exemption scenario (apart from the exemption administrative costs, and the mitigation cost and impact to health endpoints) would result in cost savings and forgone benefits. The EPA also (1) developed primacy agency burden hours and costs associated with reading and understanding the regulatory changes, developing and participating in trainings, and conducting oversight; (2) estimated PWS burden hours and costs associated with reading and understanding the rule, participating in trainings, reviewing PFOA and PFOS sampling data, planning and opting into the exemption program, updating systems' CCRs and issuing exemption PNs; and (3) estimated PWS (with PFOA or PFOS monitoring samples of 12 ppt or above) costs associated with implementing control measures for the two years covered by the exemption. The Agency assumed for costing purposes that all systems implementing control measures would conduct public education and make pitcher filters available to customers. These two control measures are the most likely to be selected by implementing PWSs (apart from system specific circumstances that the EPA has insufficient data to characterize nationally), because they represent the least cost alternatives and are administratively the least complex. As part of the assessment of public education and pitcher filter costs, the EPA used data inputs from the Lead and Copper Rule Improvements (LCRI) EA (USEPA, 2024j). The LCRI rulemaking required similar public education ( printed page 29440) activities and pitcher filter programs under some of the regulatory scenarios covered in the rulemaking. For additional detailed information on the unit cost information the EPA used in the analysis of this proposed rule, see the Economic Analysis for the Proposed Rule Extending the Compliance Date for the PFOA and PFOS Maximum Contaminant Levels, Chapter 5 (USEPA, 2025h).

Because of a lack of national level data regarding the effectiveness of public education activities geared towards the prevention of PFAS exposure, the EPA is not able to quantitatively assess the degree to which this control measure requirement would reduce the potential forgone benefits associated with the two-year exemption delay at PWSs exceeding either the MCLs for PFOA or PFOS. In the case of making pitcher filters available to customers during the two years of the exemption, the EPA was able to estimate a reduction in forgone benefits by relying on two assumptions which in large part drive the estimated results. In the absence of specific data, the EPA used the estimated 20 percent pitcher filter customer use rate from the LCRI EA (USEPA, 2024j), which implicitly assumes drinking water customers are equally concerned about the exposure effects from PFAS and lead. Also, in order to estimate the reduction in drinking water PFOA and PFOS at households, the EPA assumed that 100 percent of drinking water at households using pitcher filters would not exceed 20 ppt of PFOA and/or PFOS.^[9] Given the 20 ppt threshold assumption, pitcher filter control measure benefits may be underestimated. The directional impact from utilizing the 20 percent pitcher filter customer use rate is less clear. Because the EPA lacks PFAS specific information of pitcher filter use rates, the 20 percent assumption pulled from the LCRI EA (USEPA, 2024j) could be an over- or under-estimate of the pitcher filter use rate in the case of PFAS and therefore using the 20 percent value may result in either an under- or over-estimate of the mitigation benefits. For additional detailed information on the benefits data the EPA used in the analysis of this proposal, see the Economic Analysis for the Proposed Rule Extending the Compliance Date for the PFOA and PFOS Maximum Contaminant Levels, Chapter 6 (USEPA, 2025h).

The quantified incremental national estimated annualized costs and benefits under this proposed rule are shown in Exhibit IV-2.^[10]

The expected quantified annualized costs savings resulting from the implementation of this proposed rule is $90.2 million, in 2024 dollars, discounted at 3 percent, and $188.2 million discounted at 7 percent. The estimated quantified forgone benefits are $79.3 million (discounted at 3 percent), and $105.7 million (discounted at 7 percent). The same level of health protection from PFOA and PFOS and co-occurring DBPs is reached when compared to the baseline; however, because of the two-year delay in achieving the health protection, which is only partially offset by the quantified control measure requirements, the net present value of the health improvements is lower, reducing the calculated annualized value.

As discussed in the regulatory baseline section (the 2024 PFAS NPDWR Option 1a), the Agency cannot say with certainty the degree to which the nonquantifiable health endpoint benefits may decrease as a result of this action. Likewise, the Agency cannot say with certainty the degree to which the non-quantified PWS filter media disposal costs would decrease.

In addition to the sources of uncertainty affecting the baseline and the benefit and cost estimates which are discussed in detail in sections 4.5, 5.1.2, 5.7, 6.1.2, and 6.8 of the 2024 PFAS NPDWR EA document (USEPA, 2024e), seven additional sources of uncertainty should be considered as part of a review of SDWA 1416 exemptions proposed rule quantified impacts. These are:

1. The EPA assumes that 100 percent of systems with MCL exceedances opt into the exemption process. Although this assumption overestimates the number of systems opting into the exemption process, the system-specific nature of this decision (being based on treatment in place, capital management planning, financial projections, availability of technology venders, PFOA and PFOS occurrence, and customer preference) and the lack of data prevents the Agency from making a reliable national level estimate as to the number of systems opting into the exemption process. Therefore, the EPA ( printed page 29441) relied on economic theory in assuming that systems, like other firms, make decisions based on cost minimization,^[11] but some systems may still choose to implement treatment on a faster than required schedule. Some systems may install treatment prior to April 2029 because of the public health protection provided by PFAS treatment, customer concerns, state regulations, or other system specific factors. Therefore, the EPA's estimated cost savings and forgone benefits for this action would be overestimated. Additionally, some systems, particularly larger systems considering pitcher filters for exemption mitigation, may also find control measure requirements to be more costly than implementing the long-term treatment option, again resulting in the overestimation of cost savings and forgone benefits for this proposed rule.

2. The EPA assumes that treatment technology effectiveness and the cost of implementing treatment technology remain constant over the period covered by the exemptions. By allowing more time through the exemptions, the EPA expects that emerging technologies will become better understood and may become more widely available, improving average treatment efficacy and potentially lowering implementation and operations and maintenance costs. Because the EPA is unable to develop new technology implementation unit cost and efficacy estimates, the calculated cost savings may be underestimated.

3. There may be uncertainty in the estimated number of systems with PFOA and PFOS levels at or above 12 ppt triggering the proposed rule requirement for PFAS control measures during the period of the exemption. This may result in either an under- or over-estimate of the proposed rule's cost savings and forgone benefits.

4. The choice of public education and pitcher filters is assumed for all systems required to conduct control measures. This assumption could result in under- or over-estimates of both cost savings and forgone benefits.

5. The Agency could not provide an estimate of the effectiveness of public education activities in reducing PFAS exposure, underestimating control measure benefits which results in an overestimate of forgone benefits for the proposed rule.

6. The assumption that 20 percent of drinking water system customers will utilize PWS provided pitcher filters for 100 percent of their drinking water needs at home (rates which could be affected by public education control measures), could result in under- or over- estimates in the costs and benefits of the control measure requirements and likewise result in either an under- or over-estimate of total rule cost savings ^[12] or total rule forgone benefits.

7. The EPA assumes that when pitcher filters are used in households as a control measure, they only achieve a reduction in PFOA and PFOS to 20 ppt (the 2022 NSF/ANSI Standard 53 limit for PFOA and PFOS). For systems using devices certified under the 2022 NSF/ANSI Standard, assuming a fixed reduction level may underestimate mitigation benefits. The 2022 total PFAS reduction Standard 53 sets a combined limit of 20 ppt for seven PFAS, including PFOA and PFOS. Therefore, it is reasonable to assume PFOA and PFOS concentrations in filtered water will be below 20 ppt considering the other five PFAS as part of the combined limit. The EPA is also allowing the use of pitcher filters that have been certified under the older NSF/ANSI standard requiring PFOA and PFOS to 70 ppt. The EPA believes that even for these filters, the majority will reduce concentrations to below 20 ppt in most cases. This is because pitcher filters have been found to be generally effective in removing PFOA and PFOS, often with removal efficiencies greater than 50 percent and as high as 99+ percent in some cases (Herkert et al., 2020; Mulhern et al., 2021; Teymoorian et al., 2024; and Zarębska et al., 2025). Based on the EPA's 2024 occurrence analyses supporting the EA, and the UCMR 5 data reported through October 2025, the vast majority of PWS samples exceeding 4.0 ppt are below 40 ppt. Hence, even a pitcher filter with only 50 percent average removal efficiency will reduce water consumed to below 20 ppt in most cases. Therefore, assuming that filters reduce PFOA and PFOS only to 20 ppt may understate the protection they actually provide for the majority of time they are used as a short-term control measure and, in turn, may underestimate the control measure benefits under the proposed rule. The EPA requests the submission of additional data and comment on these six new sources of uncertainty, particularly the cost and treatment effectiveness of pitcher filters used to reduce PFAS exposures.

The EPA concludes that the proposed rule should yield annualized cost savings of $90.2 million with forgone benefits of $79.3 million, when discounted at 3 percent, and yield cost savings of $188.2 million with forgone benefits of $105.7 million, when discounted at 7 percent.

The EPA also acknowledges that a number of the long-term forgone benefits of increased PFAS exposure—such as premature mortality, higher medical expenses, lost productivity due to illness, and other reductions in welfare (measured in willingness-to-pay) which are linked to developmental and reproductive toxicity, immune system suppression, liver damage, thyroid disruption, and elevated risk of cancers—remain unquantified.^[13] The EPA estimated cost savings also do not account for the potential reduction in used filter media disposal costs.

V. Public Participation

A. Request for Comment on the Proposed Rule

The EPA seeks public comment on this proposal that provides additional compliance time meet the PFOA and PFOS MCLs for exempted systems. Specifically, the EPA seeks public comment and data on:

• The proposed national PFOA and PFOS exemption framework and the Agency's use of authority under SDWA 1416 in this streamlined fashion. ( printed page 29442)
• The proposed compelling factors, other unidentified factors, and supporting information the Agency should consider when evaluating SDWA 1416(a)(1) exemption criteria.
• If there are any other levels, aside from 12 ppt PFOA or PFOS, the Agency should consider when evaluating SDWA 1416(a)(3) exemption criteria.
• Whether the risk to human health that may occur due to exposure to PFOA or PFOS at levels less than 12 ppt, over a limited period of time, is unreasonable.
• The suitability of the six control measures identified that systems at or exceeding 12 ppt for PFOA or PFOS must select and implement during the exemption period from April 26, 2029, through April 26, 2031. The control measures include providing water pitchers and filters certified to reduce PFOA and PFOS concentrations, delivering alternative water supplies with lower levels of PFOA and PFOS, installing and maintaining POU or POE devices certified to decrease PFOA and PFOS concentrations, implementing actions and plans to decrease PFOA and PFOS levels in sources of drinking water, distributing written public education materials to consumers on PFAS exposure sources, and conducting community educational outreach activities on PFAS in drinking water, as described in section III.D.1.b.i of this preamble.
• For PWSs selecting POU or POE devices as a control measure requirement, whether the requirements of40 CFR 142.62(h) should apply.
• The proposed Tier 3 PN designation of operating under an exemption of the PFOA and PFOS MCLs and whether a Tier 2 notice should be required.
• Additional information that should be included in the Tier 3 PN of PFOA and PFOS MCL exemptions aside from requirements already specified under section III.D.1.b.ii of this preamble.
• The proposed estimated cost savings and forgone benefits from the EA for this action, including SDWA 1416 exemptions proposal, and possible alternative provisions, for example, other PFOA or PFOS reduction control measures.
• Additional data and comment on the seven additional proposed rule specific sources of uncertainty for this rule's quantified impacts, as described in section IV.B of this preamble. The EPA would particularly appreciate public comment on the cost and treatment effectiveness of pitcher filters used to reduce PFAS exposures. The Agency also asks for comment and relevant data on the assumption, used in the EA, that 20 percent of drinking water system customers would choose to use pitcher filters during the two-year exemption period.
• The assumption used in the EA that all systems exceeding either the MCL for PFOA or PFOS will opt into the proposed exemption process when the relative cost of required mitigation measures (required only for those systems with PFOA or PFOS sample results at or above 12 ppt) and other policy concerns could prompt systems to install long-term compliance technology ahead of required deadlines.
• The anticipated Paperwork Reduction Act burdens associated with this rulemaking.

B. Written Comments

Submit your comments, identified by Docket ID No. EPA-HQ-OW-2025-1742, at https://www.regulations.gov (our preferred method), or the other methods identified in the ADDRESSES section. Once submitted, comments cannot be edited or removed from the docket. The EPA may publish any comment received to its public docket. Do not submit to the EPA's docket at https://www.regulations.gov any information you consider to be Confidential Business Information (CBI), Proprietary Business Information (PBI), or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission ( i.e., on the web, cloud, or other file sharing system). Please visit https://www.epa.gov/​dockets/​commenting-epa-dockets for additional submission methods; the full EPA public comment policy; information about CBI, PBI, or multimedia submissions; and general guidance on making effective comments.

C. Participation in Virtual Public Hearing

The EPA will hold a public hearing on July 7, 2026, to receive public comment and present on the proposed rule. The hearing will be held virtually from approximately 11:00 a.m. to 7:00 p.m. eastern time, or at the conclusion of public testimony, whichever is sooner. The EPA will begin pre-registering speakers for the hearing upon publication of this document in the Federal Register . To attend and register to speak at the virtual hearing, please use the online registration form available at https://www.epa.gov/​sdwa/​proposed-pfoa-and-pfos-compliance-extension-rule. The last day to pre-register to speak at the hearing will be July 1, 2026. On July 6, 2026, the EPA will post a general agenda for the hearing that will list pre-registered speakers in approximate order at: https://www.epa.gov/​sdwa/​proposed-pfoa-and-pfos-compliance-extension-rule. The number of online connections available for the hearing is limited and will be offered on a first-come, first-served basis. To submit visual aids to support your oral comment, please contact PFASNPDWR@epa.gov for guidelines and instructions. Registration will remain open for the duration of the hearing itself for those wishing to provide oral comment during unscheduled testimony; however, early registration is strongly encouraged to ensure proper accommodations and adequate timing.

The EPA will make every effort to follow the schedule as closely as possible on the day of the hearing; however, please plan for the hearings to run either ahead of schedule or behind schedule. Please note that the public hearing may close early if there are no more people awaiting the opportunity to provide comment.

The EPA encourages commenters to provide the EPA with a copy of their oral testimony electronically by submitting it to the public docket. Oral comments will be time limited to allow for maximum participation, which may result in the full statement not being heard. Therefore, the EPA also recommends submitting the text of your oral comments as written comments to the rulemaking docket. Written statements and supporting information submitted during the comment period will be considered with the same weight as oral comments and supporting information presented at the public hearing.

Please note that any updates made to any aspect of the hearing are posted online at https://www.epa.gov/​sdwa/​proposed-pfoa-and-pfos-compliance-extension-rule. While the EPA expects the hearing to go forward as set forth earlier in this section, please monitor our website at: https://www.epa.gov/​sdwa/​proposed-pfoa-and-pfos-compliance-extension-rule to determine if there are any updates. The EPA does not intend to publish a document in the Federal Register announcing updates.

If you require any accommodations such as language translation, captioning, or other special accommodations for the day of the hearing, please indicate this as part of your registration and describe your needs by June 30, 2026. The EPA may not be able to arrange ( printed page 29443) accommodations without advance notice. Please contact PFASNPDWR@epa.gov with any questions related to the public hearing.

VI. Statutory and Executive Orders Reviews

Additional information about these statutes and Executive Orders can be found at https://www.epa.gov/​laws-regulations/​laws-and-executive-orders.

A. Executive Order 12866: Regulatory Planning and Review and Executive Order 13563: Improving Regulation and Regulatory Review

This action was determined by OMB to be a significant regulatory action as defined under section 3(f)(1) of Executive Order 12866. Accordingly, it was submitted to OMB for review. Any changes made in response to OMB recommendations have been documented in the docket. The EPA prepared an analysis of the potential costs and benefits associated with this action. This analysis, Economic Analysis for the Proposed Rule Extending the Compliance Deadline for the PFOA and PFOS Maximum Contaminant Levels (USEPA, 2025h) is available in the docket and discussed in section IV of this preamble.

B. Executive Order 14192: Unleashing Prosperity Through Deregulation

This action is expected to be an Executive Order 14192 deregulatory action. The expected quantified annualized cost savings is $189 million, in 2024 dollars, at a 7 percent discount rate and an in-perpetuity time horizon. Details on the estimated cost savings of this proposed rule can be found in the EPA's analysis of the potential costs and benefits associated with this action, see Chapter 4 and Appendix A Table A-1 of the Economic Analysis for the Proposed Rule on Extending the Compliance Deadline for the PFOA and PFOS Maximum Contaminant Levels (USEPA, 2025h).

C. Paperwork Reduction Act (PRA)

The information collection activities for this proposed rule will be submitted for final approval to OMB under the PRA. The Information Collection Request (ICR) submission is dependent on the requirements of the final rule promulgation. The EPA developed an ICR document for this proposal, assigned the EPA ICR number 7817.01. You can find a copy of the ICR in the docket for this rulemaking; it is also summarized here. Section 7.3 of the EA provides information on the proposed rule collection.

The proposed rule ICR being considered would cover information collection burden and cost associated with the existing 2024 Final PFAS NPDWR ICR (OMB control number 2040-0307, the EPA ICR #: 2732.02), as modified by the proposed rescission rule ( Rescission of Regulatory Determinations and Removal of Related Provisions for Four PFAS Substances (PFHxS, PFNA, HFPO-DA (GenX), and the mixture of these three PFAS plus PFBS) ( EPA-HQ-OW-2025-0654; the EPA ICR #: 7818.01) and this proposed national exemption framework for the three year period from April 2026 to April 2029, or until such time as the burden and costs from the proposed rule are added to the total operational burden and cost of the national drinking water program under the Information Collection Request for the Disinfectants/Disinfection Byproducts, Chemical, and Radionuclides Rules (OMB control number 2040-0204) and the Information Collection Request for the Public Water System Supervision Program (OMB control number 2040-0090). The EPA notes that a portion of the burden and cost estimates reported under this ICR, specifically compliance monitoring burden and costs, are also reported in the ICR for the Rescission of Regulatory Determinations and Removal of Related Provisions for Four PFAS Substances (PFHxS, PFNA, HFPO-DA (GenX), and the mixture of these three PFAS plus PFBS) (EPA-HQ-OW-2025-0654; the EPA ICR #: 7818.01) because each of these actions modifies the same underlying rule ( i.e., the 2024 Final PFAS NPDWR) and covers the same three years after promulgation ( i.e., April 2026 to April 2029). If the EPA takes final action in both rulemaking efforts, the Agency will prepare and submit a unified final rule ICR under one of the collections established for the proposed rules (either the EPA ICR #7817.01 or 7818.01) covering the final regulatory requirements that will be applied to the respondents in the three years following the final rules' promulgation, as applicable. This information collection does not require respondents to disclose confidential information.

Respondents/affected entities: The respondents/affected entities are PWSs and primacy agencies.

Respondent's obligation to respond: The collection requirements are mandatory under SDWA (42 U.S.C. 300g-7). Under this proposed rule, pursuant to SDWA 1416(f) and 1450(a)(1), the EPA is proposing an “exemption by rule” for systems in states that have not obtained primacy for 40 CFR part 141 subpart Z under which eligible systems may request and obtain a two-year federal exemption from the requirements related to the PFOA and PFOS MCLs until April 26, 2031. Water systems are only subject to the conditions of the exemption if they request it to be granted.

Estimated number of respondents: For the first three years after publication of the rule, information requirements apply to an average of 22,233 respondents annually, including 22,177 PWSs and 56 primacy agencies.

Frequency of response: Varies. Details can be found in the ICR for the proposed rule and Chapter 4 of the EA.

Estimated burden: 330,265 hours (per year) on average. Of these hours, 91,454 hours (per year) are attributed solely to the new requirements imposed by this proposal. Burden is defined at 5 CFR 1320.3(b).

Total estimated cost: $89.3 million per year (simple average over three years), of which $14.8 million, for an average of $4.9 million per year (simple average over three years) is attributed solely to the new requirements of this proposal.

An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB control number. The OMB control numbers for the EPA's regulations in 40 CFR are listed in 40 CFR part 9.

Submit your comments on the Agency's need for this information, the accuracy of the provided burden estimates and any suggested methods for minimizing respondent burden to the EPA using the docket identified at the beginning of this rule. The EPA will respond to any ICR-related comments in the final rule. You may also send your ICR-related comments to OMB's OIRA using the interface at www.reginfo.gov/​public/​do/​PRAMain. Find this particular information collection by selecting “Currently under Review—Open for Public Comments” or by using the search function. OMB must receive comments no later than June 22, 2026.

D. Regulatory Flexibility Act (RFA)

The EPA certifies that this action will not have a significant economic impact on a substantial number of small entities under the RFA. In making this determination, the EPA concludes that the impact of concern for this proposed rule is any significant adverse economic impact on small entities and that the agency is certifying that this proposed rule will not have a significant economic impact on a substantial number of small entities because it has no new net burden on the small entities subject to the rule. The proposed rule ( printed page 29444) extends the existing PFOA and PFOS MCL compliance deadlines and this allowance of additional time to meet the PFOA and PFOS MCLs may, in fact, relieve regulatory burden if systems are able to make more cost-effective decisions or reduce concentrations of these PFAS such that the costs of drinking water treatment are defrayed in part or whole. For small systems that decide not to take the exemption there will be no cost increase as a result of this rule. Although water systems are not required to seek SDWA 1416 exemption, for those water systems that do request the exemption there will be an increase in administrative costs; however, this increase in costs will be minimal and more than offset by the cost savings to the system of delayed implementation associated with the installation of the compliance technology, resulting in an overall cost savings to small PWSs participating in the exemption. Details on the estimated cost savings of this proposed rule can be found in the EPA's analysis of the potential costs and benefits associated with this action (section IV of this preamble). The estimated annualized total cost savings for small PWSs, defined under SDWA as those serving 10,000 or fewer persons, is estimated to be $15.7 million at the 3 percent discount rate and $32.2 million at the 7 percent discount rate, in 2024 dollars. These estimated small system savings represent approximately 17.1 percent (at the 7 percent discount rate) to 17.4 percent (at the 3 percent discount rate) of total proposed rule estimated annualized savings. The EPA has therefore concluded that this action will have no net, or possibly relieve, regulatory burden for all directly regulated small entities.

E. Unfunded Mandates Reform Act (UMRA)

This action does not contain an unfunded mandate as described in UMRA, 2 U.S.C. 1531-1538, and does not significantly or uniquely affect small governments. The action imposes no new enforceable duty on any state, local or Tribal governments or the private sector.

F. Executive Order 13132: Federalism

This action does not have federalism implications. It will not have substantial direct effects on the states, on the relationship between the national government and the states, or on the distribution of power and responsibilities among the various levels of government.

G. Executive Order 13175: Consultation and Coordination With Indian Tribal Governments

This action does not have Tribal implications as specified in Executive Order 13175. The proposed actions will not have substantial direct effects on one or more Tribes, change the relationship between the Federal Government and Tribes, or affect the power and responsibilities between the Federal Government and Indian Tribes. The proposed actions only seek to extend the compliance timeframe for the PFOA and PFOS MCLs and the compliance requirements in this proposed rulemaking are not different than those promulgated for PFOA and PFOS in the 2024 PFAS NPDWR. Water systems are only subject to the conditions of the exemption if they request it to be granted. Additionally, Tribes assuming primacy may choose not to allow the federal exemption and/or elect to issue exemptions under their SDWA 1416 authority. Thus, there is no new burden on Tribes or Tribal governments, and Executive Order 13175 does not apply to this action.

H. Executive Order 13045: Protection of Children From Environmental Health & Safety Risks

The EPA interprets Executive Order 13045 as applying only to those regulatory actions that concern environmental health or safety risks that the EPA has reason to believe may disproportionately affect children, per the definition of “covered regulatory action” in section 2-202 of the Executive Order. This action is not subject to Executive Order 13045 because it does not disproportionally diminish protections for children's health. The proposed rule discussed in this document strictly deals with providing more time to comply with the PFOA and PFOS MCL standards; the underlying MCLs and health-based MCLGs remain unchanged. This exemptions proposal, which requires eligible systems at or above a concentration threshold of 12 ppt each for PFOA and PFOS to implement control measures, ensures that the exemption will not result in an URTH over the two-year period. This action is also not subject to the EPA's Policy on Children's Health for these same reasons.

I. Executive Order 13211: Actions That Significantly Affect Energy Supply, Distribution, or Use

This action is not a “significant energy action” because it is not likely to have a significant adverse effect on the supply, distribution or use of energy. The public and private water systems affected by this action do not, as a rule, generate power. This action does not regulate any aspect of energy distribution as the water systems that are proposed to be impacted by this rule already have electrical service.

J. National Technology Transfer and Advancement Act (NTTAA)

This rulemaking does not involve technical standards. Voluntary consensus standards are technical standards utilized in regulatory and procurement activities. Since this rule is procedural and does not establish or involve technical standards, NTTAA requirements are not triggered.

K. Consultations With the National Drinking Water Advisory Council (NDWAC)

In accordance with SDWA 1412(d), “the Administrator shall consult with . . . the National Drinking Water Advisory Council” prior to proposing and promulgating a regulation under SDWA 1412. Consultation with the NDWAC is not required because this rule is being promulgated under SDWA 1416. Nonetheless, in order to solicit input to inform its decision, the Agency consulted with the NDWAC during the Council's July 28, 2025, virtual meeting. A summary of the NDWAC recommendations is available in the docket for this proposed rule (USEPA, 2025i).

VII. References

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Kentucky Energy and Environment Cabinet. 2025. PFAS Drinking Water Rule Implementation. Kentucky Division of Water. Presenters: Sarah Caywood & Jackie Logsdon. Available at: https://eec.ky.gov/​Environmental-Protection/​Water/​Protection/​DocsRegForum/​02-PFASImplementationUpdate.pdf.

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Nakazawa, Y., Kosaka, K., Yoshida, N., Asami, M., and Matsui, Y. 2023. Long-term removal of perfluoroalkyl substances via activated carbon process for general advanced treatment purposes. Water Research, 245, 120559. https://doi.org/​10.1016/​j.watres.2023.120559.

National Conference of State Legislatures (NCSL). 2025. Per- and Polyfluoroalkyl Substances (PFAS) | State Legislation and Federal Action. Available at: https://www.ncsl.org/​environment-and-natural-resources/​per-and-polyfluoroalkyl-substances.

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OMB. 2023. Circular No. A-4. Regulatory Analysis. Washington, DC: OMB. Available at: https://bidenwhitehouse.archives.gov/​wp-content/​uploads/​2023/​11/​CircularA-4.pdf.

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USEPA. 2021b. Human Health Toxicity Values for Hexafluoropropylene Oxide (HFPO) Dimer Acid and Its Ammonium Salt (CASRN 13252-13-6 and CASRN 62037-80-3). Also Known as “GenX Chemicals.” EPA-822R-21/010. Available at: https://www.epa.gov/​system/​files/​documents/​2021-10/​genx-chemicals-toxicity-assessment_​tech-edited_​oct-21-508.pdf.

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Zarębska, M., Bajkacz, S., Malorna, K., & Torchała, K. 2025. Effectiveness of pitcher and bottle filters to remove poly-and perfluoroalkyl substances (PFAS) from drinking water. Science of The Total Environment, 976, 179327. https://doi.org/​10.1016/​j.scitotenv.2025.179327.

For the reasons set forth in the preamble, the EPA proposes to amend 40 CFR part 142 as follows:

1. The authority citation for part 142 continues to read as follows:

Authority: 42 U.S.C. 300f, 300g-1, 300g-2, 300g-3, 300g-4, 300g-5, 300g-6, 300j-4, 300j-9, and 300j-11.

2. Amend § 142.2 by adding in alphabetical order the definition for “Pitcher filter” to read as follows:

3. Add §§ 142.58 and 142.59 to subpart F to read as follows:

4. Amend § 142.62 by revising paragraph (h)(7) to read as follows:

91 FR 29425