Understanding PFAS in Wastewater: Sources, Contamination, Mitigation



The water cycle is multi-faceted and complex, but also interconnected. This relationship is especially pronounced when considering the connection between water and wastewater treatment plants. Water utilities rely on upstream wastewater treatment plants (WWTPs) to replenish water source supplies and maintain quality. After treating and distributing that water to their customers, the same water goes to the local WWTP and is discharged back into the environment for the next community to drink. The cycle continues.


Every community in the country relies on their upstream neighbors to be good stewards of water quality, and both water and wastewater treatment facilities are equally responsible for water stewardship. While water plants ensure drinking water is potable, WWTPs ensure it’s of high quality for the downstream community to treat and use.


WWTPs receive all kinds of contaminants and are equipped to treat most impurities that wastewater contains to produce high-quality effluent that downstream water plants can easily treat. But not everything. Of particular concern is PFAS (per- and polyfluoroalkyl substances). PFAS has essentially infiltrated Earth’s life cycles, meaning it has no single source and can come from anywhere.


Being on the receiving end of a community’s wastewater, WWTPs have no choice but to accept these contaminants. While there are no federal regulations for WWTPs to remove PFAS yet, WWTPs’ existing relationship with downstream community water quality may cause friction between communities as water treatment plants may soon become required to remove six PFAS compounds from their drinking water sources once the EPA’s proposed maximum contaminant levels (MCLs) are finalized.


It doesn’t stop there. The EPA’s PFAS Roadmap not only includes regulations for the water we drink but goes on to propose regulating PFAS concentrations in biosolids and wastewater effluent to close the contamination loop. So, as towns address their drinking water PFAS concentrations, a new set of Clean Water Act PFAS regulations may come out and restart the process for wastewater. This may prompt the need to find funding sources, potentially raise rates, and continually communicate PFAS health concerns to consumers.


In this article, we’ll explain how PFAS contaminates water supplies and how districts, boards, and towns can mitigate their exposure to ensure they are prepared for potential upcoming drinking and wastewater PFAS regulations.


Understanding PFAS

PFAS is the umbrella term for a family of thousands of human-made chemicals that were heavily used in industrial and consumer products for over 80 years. They are commonly found in household products like non-stick cookware, stain-resistant fabrics, and firefighting foams. The same characteristics that make them desirable in industrial and consumer products are, unfortunately, what make them difficult to remove as they contaminate the water, air, and soil.

Because of their chemical composition, conventional water and wastewater treatment do not consistently treat, remove, or decompose this “forever chemical” family, allowing PFAS to persist and harm the health of humans and ecosystems.

The chemical family’s bio-persistence and widespread use have also led it to be one of the most prevalent unregulated water contaminants in water and wastewater treatment plants. This has led federal and state agencies to propose PFAS MCLs well below the concentrations in water sources today.

Given PFAS’ resistance to treatment and the EPA’s upcoming drinking water regulations, most water utilities across the US will have to fund, procure, and operate additional water treatment technologies to meet these new Safe Drinking Water Act (SDWA) requirements. To add to the complexity, PFAS come from more than one source and can enter water supplies in multiple manners.

How Does PFAS Enter Municipal Wastewater?

PFAS enters the environment through various pathways. When the chemical was first mass-produced to make “miracle products” like Teflon, companies such as DuPont proceeded to discharge wastewater containing PFAS chemicals. This practice placed many forms of PFAS into the environment for the surrounding areas to absorb. However, this chemical family has gone on to be used in various consumer and industrial applications, and its discharge is not the only source of contamination at municipal WWTPs.

Industrial Runoff

Industrial runoff is the primary culprit of PFAS contamination in the US. Industries that are most known for using PFAS in their processes are:

·     Aerospace

·     Automotive

·     Construction

·     Electronics

From leaks, improper disposal, and lack of regulatory guidelines, PFAS has found its way from these industrial facilities into the air, water, and soil that make up our environment. Due to scrutiny and research pertaining to PFAS’ health effects on fence line communities, many legacy manufacturers have ceased direct discharge of PFAS and production of PFAS products. However, their products are still in circulation and continue to impact WWTPs.

Consumer Products

Consumer products use PFAS for a host of reasons. Cookware brands incorporate them to offer non-stick products, clothing brands rely on them to provide the latest rainproof jackets, and food packaging uses them to store your takeout meal. In the case of PFAS-laden products like shampoos and conditioners, PFAS goes down millions of drains every day, making its way directly to WWTPs. These products also inevitably end up in landfills and waterways, causing PFAS to leach into groundwater and impact water sources, where the cycle continues.

Aqueous Firefighting Foam

Commonly used to contain fires sourced from hazardous, flammable liquids like jet fuel and gasoline, aqueous firefighting foam (AFFF) employs PFAS to block the flow of oxygen to a fire and prevent it from reigniting afterward. While it is quite effective in this application, it contaminates the soil it encounters, subsequently reaching the groundwater and air. To reduce the use of AFFF, fire districts and state governments have created alternative fire suppressants, trained on clean-up procedures after use, and continuously educate firefighters on its health and environmental impacts.

Groundwater Contamination

Industrial runoff, consumer products, and AFFF all contribute to PFAS groundwater contamination via usage, discard, and discharge. This is primarily done through:

·     Landfill Leaching

·     Wastewater Discharge

·     Deploying AFFF

After reaching water sources, this PFAS contaminated water goes through the water treatment process and is distributed to water utility consumers for cooking, cleaning, and drinking. After going down the drain, this PFAS contaminated wastewater makes its way to the local WWTP.

As we stated earlier, almost all US WWTPs are unequipped to treat PFAS, leading it to go through the treatment process unscathed. This highlights WWTPs’ place inclosing the contamination gap as our nation fights PFAS contamination. It’s also why the EPA has pointed to WWTPs as a potential regulation point for the nation’s PFAS approach.

Impact of Wastewater Pollution

WWTP performance affects the health and economies of local and downstream communities. Without clean water to source from, communities become burdened with higher drinking water treatment costs, health hazards at recreational sites, and damage to ecosystems. Downstream communities depend on their upstream neighbors to be stewards of their own environment and those around them. When neighbors communicate expectations and mutual water challenges, they can positively impact water quality, water resources, and the cost of treatment.

When this communication breaks down, the results can have long and short-term effects on public health and the environment. When not treated correctly, wastewater pollution can:

·     Cause damage to aquatic ecosystems with bacteria.

·     Create hypoxic zones that suffocate aquatic life.

·     Spread water-borne illness to those who come into contact.

·     Increase the chemical and energy demand required to meet SDWA standards.


Mitigation Strategies

Although there is uncertainty that PFAS will be regulated at WWTPs, the current intricate relationship between water and wastewater plants and the EPA’s PFAS Roadmap suggest that a comprehensive regulatory framework may emerge. With this in mind, it’s advantageous for WWTPs to follow in the footsteps of proactive water providers that benefitted from getting ahead of PFAS regulations.


Fortunately, PFAS removal and destruction technology are commercially available, and WWTPs can rely on the same technologies that water utilities may come to use. These include granular activated carbon (GAC), advanced ion exchange (AIX), and reverse osmosis (RO). However, each of these methods will come at a significant capital and operational cost to utilities nationwide.


If you suspect that your wastewater system’s effluent or biosolids may contain PFAS, you may want to seek help from a legal professional with experience in water contamination litigation to explore whether you may be able to seek to hold PFAS manufacturers accountable for the costs of wastewater treatment. SLEnvironmental Law Group focuses exclusively on water contamination cases and works on a contingency fee, meaning that your utility only incurs legal expenses if a favorable outcome is achieved. Contact SL Environmental Law Group today to learn more about the available strategies to address contamination concerns.