PFAS (Per- and Polyfluoroalkyl Substances) are a class of over 4,700 synthetic fluorinated compounds. Their key feature is a fluorine-carbon (C–F) bond, one of the strongest in chemistry, which makes PFAS highly resistant to heat, chemical breakdown, and environmental degradation. This durability means PFAS persist indefinitely in water, soil, and living organisms—hence the name “forever chemicals.”

In 2024, the EPA finalized Maximum Contaminant Levels (MCLs) for several PFAS:

PFOA and PFOS: Set at 4 parts per trillion (ppt) each.

GenX (HFPO-DA) and PFBS: Regulated individually at higher ppt thresholds.

PFNA and PFHxS: Addressed in a combined hazard index approach.

These levels are extremely low, reflecting the toxicity of PFAS even in trace concentrations.

Utilities must monitor and treat water to meet these limits.

PFAS contamination occurs through several pathways:

Industrial discharges from manufacturing plants.

Wastewater treatment plant effluent, which returns PFAS-laden water to rivers.

Firefighting foam (AFFF) runoff from military bases and airports.

Landfill leachate and biosolids applied to agricultural fields.

Atmospheric deposition from PFAS released through factory emissions.

Once PFAS reach surface water or groundwater, they spread widely and infiltrate municipal supplies.

There is no single “perfect” technology, but leading options include:

Granular Activated Carbon (GAC): Effective for long-chain PFAS like PFOA and PFOS, but less efficient for short-chain compounds such as GenX.

Ion Exchange (IX): Strong-base anion resins can remove both long- and short-chain PFAS, but resin fouling and PFAS-concentrated brine disposal remain challenges.

Reverse Osmosis (RO) and Nanofiltration (NF): RO provides comprehensive removal of nearly all PFAS, while NF is more energy-efficient but less effective on short-chain PFAS. Both generate brine waste streams requiring careful disposal.

Advanced Oxidation Processes (AOP) and Electrochemical Oxidation: These methods can potentially degrade PFAS at the molecular level, but they are energy-intensive and still emerging technologies.

Carver Water often engineers integrated systems (e.g., GAC + RO + IX polishing) to balance cost, efficiency, and waste management.

This depends on the method:

Adsorptive methods (GAC, IX): PFAS are captured in the media, which then becomes hazardous waste requiring regeneration or high-temperature incineration.

Membrane methods (RO, NF): PFAS are concentrated into a brine waste stream, typically 15–25% of the treated water volume. Brine disposal (deep well injection, evaporation ponds) is costly and tightly regulated.

Destructive methods (AOP, Electrochemical): Aim to break down PFAS into less harmful byproducts. However, incomplete degradation can lead to toxic intermediates, and these technologies are still under optimization.

According to Bluefield Research, U.S. utilities will spend over $3 billion annually by 2030 on PFAS remediation technologies. Drivers include:

-Growing public health awareness.

-New state and federal mandates under the Safe Drinking Water Act.

-Federal grants funding PFAS technology pilots.

-Legal liabilities faced by manufacturers and utilities.

This makes PFAS the next major challenge for U.S. water utilities.

Ultra-low regulatory limits (parts per trillion) require highly sensitive monitoring and treatment.

Short-chain PFAS removal remains technically difficult.

Disposal of PFAS waste (spent media, brine) is costly and environmentally sensitive.

High operational costs for advanced technologies like RO and AOP.

Uncertainty around future regulation—EPA is expected to expand its list of regulated PFAS compounds.

Carver Water’s role is to help utilities choose the right mix of technologies, secure funding, and manage ongoing compliance.