Test the Water

Langan at the Forefront on PFAS-Contaminated Drinking Water

Federal and state agencies are adopting stringent drinking water standards to protect against risks associated with PFAS, increasing the need for effective PFAS water treatment solutions. While regulations may vary from agency to agency, the goal remains the same for water purveyors: support the community by identifying and implementing effective and economical remedies for PFAS-contaminated drinking water. These efforts often begin with PFAS due diligence, where utilities and project teams evaluate potential contamination risks and determine appropriate treatment strategies.

Key Takeaways

• PFAS water treatment is critical to meet evolving drinking water standards and protect public health.
• Common technologies, including granular activated carbon (GAC), ion exchange, and membrane filtration, are used to remove PFAS.
• Effective system design requires careful evaluation of site conditions, water quality, and long-term operational needs.
• Langan’s experience evaluating and implementing PFAS treatment solutions helps support effective treatment system design and long-term performance.

What Is PFAS Water Treatment?

PFAS water treatment refers to the processes used to remove or reduce per- and polyfluoroalkyl substances from drinking water using specialized technologies. Because PFAS are highly persistent and resistant to conventional drinking water treatment methods, utilities rely on approaches such as adsorption, ion exchange, and membrane filtration to achieve required water quality standards.

PFAS presents many challenges that must be considered when designing and operating PFAS-removal treatment systems. The chemicals are highly soluble, have both hydrophobic and hydrophilic properties, and contain strong intermolecular bonds, all of which limit many treatment technologies. While tried-and-true treatment methods exist, they can be costly to install, operate, and maintain, including management of PFAS waste. Additionally, stringent drinking water standards require treatment methods to reduce PFAS to nearly non-detectable levels. To navigate these obstacles, involved parties should engage a consultant with knowledge and experience in PFAS treatment.

Common PFAS Water Treatment Technologies

Designing these water treatment systems for PFAS is not a one-size-fits-all approach, however, three technologies are typically used to help remove PFAS from drinking water:

• • • Granular Activated Carbon (GAC): Uses porous carbon media to adsorb PFAS compounds from water, making it one of the most widely used treatment methods for drinking water systems.
    • Ion Exchange Treatment: Uses synthetic resins with charged sites that attract and bind PFAS molecules, often providing higher capacity and selectivity for certain PFAS compounds.
    • High-Pressure Membrane Systems (e.g., Reverse Osmosis): Uses semi-permeable membranes to physically separate PFAS from water, achieving very low concentrations but generating a concentrated waste stream.

An experienced environmental team understands the importance of conducting a thorough evaluation of possible treatment options based on site conditions, system demand, water quality, and operation and maintenance feasibility.

PFAS Water Treatment Solutions with Langan

Langan is well-versed in narrowing down potential options and enlisting its in-house treatability team to perform pilot studies, pinpoint the appropriate technology, derive system design criteria, and identify potential challenges related to the proposed treatment alternative. The firm’s multidisciplinary approach allows teams to implement the design holistically and in sync with contractors, and develop operation, maintenance, and monitoring documentation to support future system management. By participating in this process, engaging a consultant with experience navigating the PFAS regulatory framework, and communicating with residents and regulators, water purveyors are better prepared to address community concerns about PFAS.

Kimberly Semon, PE, LEED GA, has over 10 years of experience in chemical, environmental, and water engineering. Her expertise includes treatment of emerging contaminants in groundwater, groundwater hydrology, water resource planning and management, environmental oversight, and subsurface remedial design and implementation. She is also well-versed in New York City and State regulatory programs, including the Brownfield Cleanup Program and Voluntary Cleanup Program.

PFAS Water Treatment FAQs

What removes PFAS from water?

PFAS can be removed from water using specialized treatment technologies such as granular activated carbon (GAC), ion exchange resins, and high-pressure membrane systems like reverse osmosis. These methods work by capturing or separating PFAS from water, as conventional treatment processes are not effective at removing these compounds.

What are the limitations of PFAS water treatment technologies?

While effective at removing PFAS from water, many treatment technologies do not destroy the compounds and instead concentrate them in filtration media or waste streams that require additional management. These systems can also be costly to install and operate, and performance may vary depending on water chemistry, PFAS concentrations, and system design.

Why are PFAS hard to remove from water?

PFAS are difficult to remove because they are highly stable and resistant to degradation, due in part to the strength of the carbon–fluorine bond. Their unique chemical properties, including both hydrophobic and hydrophilic characteristics, allow them to persist in water and limit the effectiveness of many conventional treatment methods.