How water utilities can prepare to comply with new EPA PFAS regulations

EPA’s proposed rule regulating PFAS in drinking water is here; here’s what water utilities need to know.

In March 2023, the US Environmental Protection Agency (USEPA) announced the proposed National Primary Drinking Water Regulation (NPDWR), expected to be complied with at entry points to distribution systems, for six PFAS, or per- and polyfluoroalkyl substances. These man-made chemicals are used in a variety of water, heat, and oil-resistant products, like non-stick cookware and firefighting foams. Highly anticipated, the proposed rule includes not just PFOA and PFOS, the two most commonly found PFAS compounds, but also four other compounds: PFNA, PFHxS, PFBS, and GenX chemicals.

As these contaminants are found everywhere - including in many surface waters, groundwaters, water sources near fire-fighting facilities, and waters impacted by upstream wastewater discharges - this regulation will affect a large number of water utilities. With the USEPA expected to finalize NPDWR in 2024, utilities have little time to put together a clear plan for compliance and to seek funding.

In this Q&A, Garver Water Practice Leader Zaid Chowdhury, PhD, PE, BCEE, author of American Water Works Association's Activated Carbon: Solutions for Improving Water Quality, distills the 400-page proposed rule into what utilities need to know about how they will be affected, and what actions they need to take.

What does the regulation entail and how will it affect water utilities?

As expected, the NPDWR requires water utilities to limit concentrations of PFOA, PFOS, and four additional compounds. The maximum contaminant level (MCL) for both PFOA and PFOS are set at four parts per trillion (ppt) or 4.0 nanograms per liter (ng/L). This concentration is what the USEPA believes people can reliably measure. And at this low level, many water utilities will be impacted by this rule.

It is worth noting that during the comment period for this rule, many stakeholders submitted feedback to USEPA. American Water Works Association (AWWA), for example, submitted comments on behalf of the water industry, pointing out that the implementation of the rule as proposed faces a number of obstacles, including cost, limited resources for technology installation, and supply chain issues. AWWA advocated for an MCL of 10 ng/L instead of 4 ng/L, finding that this MCL would be both protective and affordable.

USEPA has addressed submitted comments in the rule and sent it to the Office of Management and Budget. It is expected that USEPA has addressed AWWA’s comment specifically in some way, shape, or form in the rule. When the rule is finalized, we will know for certain. In the meantime, utilities should plan for a MCL of 4 ng/ L.

For the four additional compounds - PFNA, PFHxS, PFBS, and GenX - utilities must adhere to a Hazard Index (HI), calculated using this formula: 

Formula image

In this formula, the numerators are the concentration of the respective compounds in ng/L and the denominators are the USEPA-specified health-based water concentration (HBWC) in ng/L. The calculated HI must be below 1.0 at the entry point to the distribution system.

Water utilities will need to analyze finished water at points of entry into the distribution system and measure the concentration of these six compounds. Depending on what they find, they may need a general engineering study to determine the best course of action for any new treatment system. Those who find their levels are within regulation will still need to monitor and continue to prove that their numbers are below the standard the USEPA has set. Basically, everyone will have to do something to comply with this rule.

How is this regulation expected to evolve? 

There are thousands of PFAS compounds in our environment. USEPA currently has approved methods for analyzing approximately 40 specific PFAS compounds. They are employing these methods now to assess the national occurrence of 29 different PFAS compounds at the entry points to distribution systems as a part of the fifth Unregulated Contaminant Monitoring Rule (UCMR5). This monitoring is expected to be complete by the end of 2025.

At the same time USEPA is collecting occurrence data from the nation’s water utilities, toxicologists at USEPA are researching and quantifying the risk of additional PFAS compounds. Through this research, they’ve developed the reference dose (RfD), or maximum allowable oral amount of a toxic substance, for toxic compounds. These are expressed in mg/kg-day, or the daily dose in milligrams per kilograms of body weight. USEPA expects poisonous effects if a compound is taken in at the level of the RfD.

Reference doses, along with the occurrence of the compounds in our environment, form the backbone of any regulation. And the lower the RfD, the higher the toxicity of the compound.

The following table shows the RfD of relevant compounds and the date that the RfD was made public. Note that USEPA has changed RfDs over time as more information became available.




























Compounds with regulation under the proposed rule: PFOA, PFOS, PFNA, PFHxS, PFBS, and Gen X chemicals. Compounds without regulation: PFBA and PFDA.

The RfDs for the compounds without proposed regulations are as low or lower than those covered by the proposed NPDWR. So, the compounds without regulation are as toxic as the compounds with regulation, or more so. Therefore, in future revisions of the rule, it is likely USEPA will add more compounds to the regulated list. 

Finally, note that the HI approach streamlines future rulemaking, as USEPA can add more terms to the HI calculation. Bottom line: as USEPA justifies that regulation can meaningfully reduce the risk of compounds that appear widely in our waters through UCMR5 and possibly later UCMRs, expect more compounds to be regulated.

What steps should utilities take to be prepared for, and in compliance with, the regulation, and when?

While no action is required from water utilities until USEPA finalizes NPDWR, it would be prudent for utilities to begin taking these steps now.  

Step one for utilities is to determine the characteristics of their finished water - not their source water - to see where they are with respect to the proposed rule. The NPDWR allows the use of any data collected since 2019, as long as appropriate methods were utilized. Whether using previously collected data or not, setting up monitoring at any entry point into the distribution system and measuring the concentration of these six compounds is the first step. If the utility is already performing UCMR5 monitoring, that data could be used for this purpose.  

If a utility needs a new treatment system, step two is to begin lining up funding immediately. A new treatment system usually takes two to three years from concept to operation. This rule probably will not allow for that much time. Utilities will likely have around 18 months. Lining up funding as soon as possible, whether in capital improvement plans or through grant applications, will be crucial.  

While working on funding, utilities should begin with a general engineering study to help select the treatment technology that best fits their needs. GAC adsorption, anion exchange, nanofiltration, and reverse osmosis are considered the best available technologies (BAT) for PFAS removal. 

How much will compliance cost? How can utilities acquire funding?

USEPA has estimated the cost of this new rule to be approximately $1 billion per year. But AWWA estimates the yearly cost could be two to three times that estimate.

The Bipartisan Infrastructure Law set aside $9 billion for PFAS-impacted drinking water systems. The process for the dispersal of federal funding to utilities will vary from state to state. The best way forward for now is to explore and learn as much about what the funding process may look like in your area. Click here to view an EPA fact sheet.

How can Garver help?

We bring lessons from a wealth of water treatment experience, from the early days of applying granular activated carbon for disinfection byproduct control to today, developing process trains to meet water utilities’ needs to both meet long-standing water quality and new PFAS removal goals. As regulations and PFAS removal technologies change, it is important to keep up to date, which I have done as a member of AWWA’s Technical Advisory Workgroup, an editorial board member for AWWA’s Water Science Journal special PFAS issue, and project technical advisor for all of Garver’s PFAS related projects.  

Garver is ready to help water utilities identify the best treatment technology for their site-specific needs, and we have experience designing the treatment systems needed. We can also assist water utilities with the development and implementation of a monitoring program to assess their status with respect to this rule.  

Our funding experts have years of experience identifying federal, state, and local government funding opportunities for water projects and for PFAS. They are ready to help water utilities create the funding strategy that best suits their needs, and they can assist clients with everything, from finding the right programs to submitting complete applications to implementing awarded funding.  

We also have strong working relationships with academia and researchers in this field. For example, Garver is a member of the Nanotechnology Enabled Water Treatment (NEWT) Center at Arizona State University and Rice University. We can leverage our membership to provide our clients with more efficient evaluation of potential treatment technologies at less cost.  

Garver’s four Water Design Centers, Water Technology Team, and local teams provide personalized, dedicated service to our water utility clients as well as the high levels of expertise and resources necessary to help them best prepare to comply with this rule.  

To learn more about the new PFAS standard and what utilities need to do to comply, contact Garver Water below.  

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