A Tiny Bit Of PFAS

By Kevin Westerling,
@KevinOnWater

In the most recent edition of Water Innovations, there is not a single article focused on PFAS. That wouldn’t be exceptional if not for the fact that discussion around per- and polyfluoroalkyl substances has so thoroughly dominated the water space lately. And yet, I penned this as an intro to the edition — just “a tiny bit of PFAS” content — because a small portion of PFAS is of the utmost importance in terms of treatment, policy, and cost.

When the U.S. EPA finalized the National Primary Drinking Water Regulation (NPDWR) limiting PFAS in drinking water in April 2024, the maximum contaminant levels (MCLs) were mandated at 4 parts per trillion (ppt) for PFOS and PFOA. The rule also includes new limits for four compounds — an MCL of 10 ppt for PFNA, PFHxS, PFBS, and GenX chemicals. Further, it mandates treatment when a 1.0 “Hazard Index” threshold is reached for mixtures of two or more of PFHxS, PFNA, HFPO-DA, and PFBS compounds.

Those are tiny numbers.

Pursuant to the mandatory monitoring period, utilities must start reporting results three years after promulgation of the rule. Utilities that are above the MCL thresholds must have reduction steps in place and alert consumers of exceedances after five years.

In the water industry, that is not a lot of time.

The American Water Works Association (AWWA), the largest organization of water supply professionals in the world, and the Association of Metropolitan Water Agencies (AMWA), which represents the largest (metropolitan) publicly owned water utilities in the U.S., took notice — and action.

In a joint statement from AWWA CEO David LaFrance and AMWA CEO Tom Dobbins, the pair stated:

“We are concerned ... that EPA did not use the best available data and appropriate processes in developing the PFAS regulation. For example, we question the use of a novel ‘Hazard Index’ in place of a Maximum Contaminant Level for mixtures of certain PFAS, and the issuing of a preliminary determination to regulate certain PFAS simultaneously with the proposed rule.

“The rule significantly underestimates nationwide costs, does not take into account the latest PFAS data, and will add to affordability challenges for many households without achieving the public health outcomes we all seek.

“Scientific process matters, especially when it will set precedent for how EPA develops future drinking water regulations. AMWA and AWWA therefore believe it is prudent to ask a court to verify that EPA constructed the PFAS regulation according to the letter and spirit of the Safe Drinking Water Act, and to give EPA an opportunity to revisit any components of the rule that fell short.”

According to two of the most influential water organizations, the “small” parts of the PFAS NPDWR — low limits combined with a short compliance schedule (court consideration could extend the deadlines) — could have large, and detrimental, impact.

It should be noted that at the outset of their statement, LaFrance and Dobbins express their support for a national PFAS regulation, and even the EPA’s decision to “swiftly pursue development” of the rule. But they also stated the imperative “to maximize public health benefits in a cost-effective manner.”

Did the EPA move too swiftly to meet utilities’ treatment and cost concerns? Maybe just a tiny bit.