Next Steps in Regulating PFAS

This article originally appeared in WQP June 2020 issue as "Regulatory Determination"

In the U.S. EPA’s National PFAS (per- and polyfluoroalkyl substances) Action Plan, published February 2019, the agency identified the water treatment industry as a part of the solution. It stated: “If you find PFAS in your drinking water, certain PFAS can be reduced or removed through the use of in-home point-of-use (POU) or point-of-entry (POE) water filters. It is important to keep in mind that any in-home treatment device should be certified by an independent party.”

One year after announcing its PFAS Action Plan, EPA provided an update on its progress. Notable updates on addressing PFAS in drinking water included developing laboratory methods for detecting and identifying PFAS in drinking water through EPA Method 533 and the regulatory determination of perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA).

The EPA is following the process laid out in the Safe Drinking Water Act (SWDA) for evaluating currently unregulated contaminants to determine how it should be regulated. The EPA has multiple options for setting enforceable and unenforceable regulations. For example, there is currently a lifetime health advisory for combined PFOS and PFOA in drinking water at 70 parts per trillion (ppt). This is an unenforceable regulation meant to provide guidance and is based on health effects information to estimate acceptable drinking water levels for the contaminant.

Considering PFAS Regulations

To begin the path to publishing a national primary drinking water regulation for PFOS and PFOA, the EPA has considered three
key criteria:

1. The contaminant may have an adverse effect on the health of persons;
2. The contaminant is known to occur or there is a substantial likelihood that the contaminant will occur in public water systems with a frequency and at levels of public health concern; and
3. In the sole judgement of the EPA administrator, regulation of such contaminant presents opportunity for health risk reduction for people served by public water systems.

As stated in the agency’s report, the EPA has decided to move forward with regulatory determination of PFOS and PFOA to regulate both contaminants under the Safe Drinking Water Act (SDWA). This was the next step towards setting an enforceable regulation. Through a primary drinking water regulation, the EPA will have two options. The first is through a maximum contaminant level (MCL) and the second is through a treatment technique rule (TTR).

An MCL is the most common national primary drinking water regulation. It sets the highest contaminant level allowed in drinking water. There is also a maximum contaminant level goal (MCLG), like a health advisory, which focuses on setting a level solely on health effect research. The MCLG is not enforceable but is used to help set the MCL which will also consider the costs and benefits of the proposed level; any increased health risk to the general public as a result of the new MCL; and other relevant factors.

For instance, the agency will look at technologies to achieve compliance that are affordable for systems serving less than 10,000 people. The agency may adjust the level to reconcile cost of treatment and maximize the reduction of health risks.

If an MCL is impractical because there is not a feasible way to measure the contaminant concentration, either economically or technically, the EPA can develop a TTR. For example, the Lead and Copper Rule sets up monitoring and testing at the tap, treatment (i.e. corrosion control), and reporting requirements.

PFAS Action Plan Next Steps

In the 2020 PFAS Action Plan Update, the EPA said it will continue to investigate other PFAS chemicals as it simultaneously moves forward with PFOS and PFOA. Under the SDWA, the agency is required every five years to issue a list of unregulated contaminants for public water systems to monitor and report back occurrence data following the EPA’s guidelines. This is called the Unregulated Contaminant Monitoring Rule (UCMR). Under the recent National Defense Authorization Act for Fiscal Year 2020, the EPA will include PFAS in its upcoming UCMR cycle.

Looking ahead, the EPA will be reviewing its proposal for regulating PFOS and PFOA and public a call for comments will immediately follow. Under the SDWA, once a new national primary drinking water regulation goes into effect there is a three-year period for systems to come into compliance. The EPA administrator or states can extend this period for another two years. All existing regulations are reviewed by the EPA every six years.