Environmental Protection Agency Sets First-Ever Legally Enforceable Limits for PFAS Chemicals in Drinking Water

In April 2024, the Environmental Protection Agency (EPA) announced the first-ever national, legally enforceable drinking water standards for per- and poly-fluoroalkyl (PFAS) substances. Known as “forever chemicals,” PFAS poses significant risks to public health. Studies have shown links between PFAS and liver damage, thyroid disease, immune system changes, developmental effects or delays in infants and children, higher rates of certain cancers and higher cholesterol levels. The clock has started for water districts to act and protect public health by providing safe, clean drinking water that abides by the new enforceable PFAS limits. 

The New PFAS Limits

Restrictions have been imposed for five individual PFAS: PFOA, PFOS, PFNA, PFHxS and HFPO-DA (also known as “GenX Chemicals.”) There are also rule limits for mixtures of any two or more of four types of PFAS: PFNA, PFHxS, PFBS and “GenX Chemicals.” See the chart below for specific level requirements. The enforceable limits are represented by Maximum Contaminant Levels (MCLs), while the Maximum Contaminant Level Goals (MCLGs) are health-based and non-enforceable.

CompoundFinal MCLGFinal MCL
(Enforceable Levels)
PFOA04.0 parts per trillion (ppt)
PFOS04.0 ppt
PFHxS10 ppt10 ppt
PFNA10 ppt10 ppt
HFPO-DA (“GenX Chemicals”)10 ppt10 ppt
Mixtures containing two or more of PFHxS, PFNA,
HFPO-DA and PFBS
1 (unitless)
Hazard Index
1 (unitless)
Hazard Index

The Timeline for Testing and Treatment

All public water systems must complete initial testing for PFAS chemicals by 2027, followed by ongoing compliance monitoring. Beginning in 2027, public, regulated water districts are responsible for informing the public of the levels of PFAS measured in their drinking water on an ongoing basis.

If testing finds PFAS levels that exceed the legally required standards, the water district must notify the public and act to reduce the levels of PFAS in the drinking water by 2029.

How You Can Test for PFAS and Get Compliant

Technological developments such as granular activated carbon, reverse osmosis and ion exchange systems can filter PFAS appropriately. The EPA has allocated $1 billion to help water districts resolve PFAS in the drinking water, and districts have the flexibility to determine the best solution for their community.

While this all may sound overwhelming, RK Water is ready to support you through the entire process. We can:

– Perform initial PFAS sampling and testing.

– Identify and evaluate the PFAS compounds requiring treatment and identify the appropriate treatment method.

– Evaluate site-specific conditions, sustainability of the treatment method and cost-effectiveness of viable treatment options.

– Perform CAPEX vs. OPEX evaluation of competing treatment options.

– Design, procure and install temporary or long-term treatment system equipment.

– Operate and maintain treatment systems.

– Provide compliance testing and reporting.

– Handle media change-outs and disposal management.

If you’re ready to be at the forefront of enhancing public safety, contact RK Water today!

Additional Resources from the EPA

New PFAS Limits Announcement

PFAS Information Page

General Fact Sheet

General FAQs

FAQs for Drinking Water Primary Agencies