What to know about PFAS in Delaware: local impacts, risks, and what’s being done

PFAS are found in a wide range of products and environments, and once released, they don’t go away easily. (Photo by FREEPIK)

Between new treatment efforts in Stanton and ongoing concerns about contamination in the Christina River, PFAS have emerged as a growing concern in Delaware, raising questions about health, accountability, and cleanup.

So, what are PFAS? And why do they matter?

PFAS—short for per- and polyfluoroalkyl substances—are a class of human-made chemicals used in products like nonstick cookware, waterproof clothing, and firefighting foam. They’re known as “forever chemicals” because they don’t break down easily and can accumulate in the human body and environment.

Where PFAS are showing up in Delaware

A recent Delaware Currents article identified the Christina River as a “hotspot” for both legacy contaminants and PFAS. This includes areas in Wilmington and the surrounding Christina Basin, such as the Brandywine River, Red Clay and White Clay creeks, Shellpot Creek, and several smaller tributaries.

The Delaware Department of Natural Resources and Environmental Control (DNREC) has been tracking contamination through its Watershed Approach to Toxics Assessment and Restoration (WATAR) program.

The DNREC said that between 2013 and 2018, it “collected a comprehensive set of sediment, surface water and fish tissue samples from watersheds across the state.”

In a statement to Delaware Live, DNREC wrote that its 2015 evaluation of the Christina Basin “identified the tidal Brandywine River and lower tidal Christina River as an area that was more impacted when compared to other areas. As such, additional investigation and source control actions have occurred since that time in an attempt to reduce the associated impacts to aquatic life and human health.”

PFAS were not part of that 2015 assessment, but DNREC has since expanded its scope. The agency said it is now investigating “drinking water, groundwater, wastewater, soil, sediment, fish tissue, air, biosolids, etc. in an attempt to characterize PFAS impacts and to help prioritize resources.”

The agency emphasized that “it’s not a surprise to DNREC scientists that PFAS concentrations are elevated in some of the industrialized areas of the state where legacy contamination is also greater.”

Who is most at risk?

Some Delawareans may be more vulnerable than others. According to the Delaware Division of Public Health (DPH), “children, pregnant individuals, and low-income communities may face heightened risks due to factors such as developing physiology, increased exposure through water and food, and limited access to mitigation resources.”

Laura Matusheski, spokesperson for DPH, cited peer-reviewed EPA research showing that PFAS exposure may lead to “reproductive effects such as decreased fertility or increased high blood pressure in pregnant women and developmental effects or delays in children, including low birth weight, accelerated puberty, bone variations, or behavioral changes.”

A new treatment plant in Stanton

One of the most visible responses to PFAS in Delaware is the new Veolia PFAS treatment facility, which opened in Stanton earlier this summer. It provides filtered drinking water for more than 100,000 residents in New Castle County and is expected to meet federal PFAS standards ahead of schedule.

“Yes, the new Stanton PFAS treatment facility is expected to significantly reduce public health concerns in the area by removing PFAS from the water supply,” said Matusheski. “DPH will measure its impact through ongoing water quality testing and health monitoring.”

Environmental attorney James L. Ferraro Jr., who represents public water systems nationwide, called the plant “a positive” step. 

“Some of our clients would look very similar to that,” he said. “They were totally caught off guard with this. They didn’t even know PFAS was in the water. They didn’t even know what PFAS was until the recent past.”

Ferraro said the treatment facility is likely using granular activated carbon, “generally one of the three treatment technologies that can filter out PFAS” and noted that even at $35 million is pretty cheap for facilities of this size. 

“Sometimes you’re seeing a moderately sized community looking at a nine-figure bill” to build or upgrade their treatment systems,” he said.

Why are PFAS so hard to control?

PFAS are found in a wide range of products and environments, and once released, they don’t go away easily.

“PFAS are just so ubiquitous, not only in the United States, but around the globe. Unfortunately, you find PFAS now in the most remote places,” Ferraro explained. “It’s in 98-plus percent of the human population’s blood at some level.” 

Some of the most concentrated PFAS “point sources,” he said, include military bases, airports, and fire training facilities, largely due to the historic use of aqueous film-forming foam (AFFF) in firefighting.

Industrial facilities are also major contributors to the PFAS problem, such as the DuPont company.

“DuPont is a huge company in Delaware,” Ferraro said. “They’re a big defendant in the [national PFAS litigation]. Some of those point sources are industrial facilities that are either manufacturing PFAS or building a product where PFAS is used in high concentrations, and it’s discharged into a local water source.”

After reaching out to DuPont’s communication team about these claims, their spokesperson stated, “DuPont de Nemours has never manufactured PFOA, PFOS or firefighting foam.”

That claim is technically true because of a corporate restructuring. In 2015, the original DuPont—E.I. du Pont de Nemours—spun off its performance chemicals business into a new company, Chemours, transferring PFAS-related products, manufacturing facilities, and environmental liabilities to the new entity.

In 2019, DuPont de Nemours was formed as part of a corporate merger and reorganization, separate from the legacy company. The original DuPont has since been renamed EIDP, Inc., and is now part of Corteva Agriscience.

Still, DuPont’s long-standing presence and influence in Delaware remain significant. According to the company’s website, “has used science and technology to empower the world with essential innovations” for over 115 years. Among those innovations,  the discovery of Teflon (PTFE) in 1938, a nonstick coating that became one of the most commercially successful and environmentally persistent PFAS compounds.

In June 2023, Chemours, DuPont de Nemours, and Corteva announced a $1.185 billion settlement to resolve PFAS-related drinking water claims from public water systems across the U.S. The agreement covers systems with PFAS detections or those required to monitor under EPA rules, including many AFFF. Under the deal, Chemours contributed 50% of the settlement fund, while DuPont and Corteva split the remaining half.

The companies denied any wrongdoing but said the settlement was intended to “comprehensively resolve” litigation and avoid prolonged legal battles.

What’s the state doing about it?

Delaware agencies say they are working aggressively to understand and address the threat.

DNREC is prioritizing its response using “an exposure and data-driven approach.” That means focusing first on how humans are most likely to encounter PFAS, especially through drinking water.

“DNREC (and DPH) has focused on ensuring that drinking water sources (surface water and groundwater) are being evaluated and that water is being effectively treated to minimize that exposure,” DNREC wrote in a statement. 

Cleanup is complex, and officials caution that remediation will take time.

“All of the watershed sources of toxic compounds present in the water body must be identified and controlled,” DNREC explained. “Otherwise, an ‘in-water’ remedial action would be re-contaminated in a short period of time.”

What about long-term health risks?

Unlike some pollutants, PFAS are still actively manufactured. That puts them in a different category from legacy contaminants like PCBs or dioxins, which have been banned for decades.

Still, the long-term health effects of PFAS are not fully understood, and DNREC says the science is evolving. 

“The overall point is that PFAS likely interact in some ways with other legacy contaminants, and at a minimum co-exist with legacy contaminants, with the potential to cause human and ecological health impacts. The science around PFAS and its relationships with other chemicals in the environment is still in its infancy.” 

Ferraro said lawsuits have aimed to hold major polluters accountable and to help cover treatment costs for water systems like Stanton’s.

“There’s been some settlements on behalf of 3M and DuPont and a few others that compensate public water systems who participated for costs like this,” he said. 

What residents should know

As PFAS concerns rise nationally, Ferraro warned that blame is sometimes misplaced.

“Some people intuitively would think, ‘Okay, this government entity, this public water system- maybe they did something that put this in the water,’” he said. “That point in that direction is misguided; they didn’t put this in the water. The people who put this in the water and hid the dangerousness are the 3M and DuPonts of the world.”

He urged residents to stay informed and to recognize the steps their local systems are taking to respond. 

“It doesn’t happen overnight. It takes a lot of planning, engineering, and design. And there are also some federal dollars out there to address some of these costs.”

Federal standards are driving local action

PFAS regulation is gaining traction at the national level, and that’s directly affecting how Delaware communities respond. In April 2024, the U.S. Environmental Protection Agency (EPA) finalized a national drinking water standard for six PFAS compounds. Two of the most common (PFOA and PFOS) are now regulated at just 4 parts per trillion, the lowest level detectable by current technology.

“Once those are final, all the states have to basically abide by those federal standards, or they could go lower,” said Ferraro. “It’s going to be binding on not only Delaware, but every public water system in the country.”

The EPA initially set a compliance deadline of 2029, but extended it to 2031 to give communities more time to test, plan, and build treatment infrastructure. 

Delaware is also receiving substantial federal support to help meet those goals. According to DPH, the EPA recently awarded $19.4 million through its Emerging Contaminants Grant to help small or disadvantaged communities in the state install PFAS treatment systems. DPH also receives around $7.6 million annually through the Drinking Water State Revolving Fund for PFAS mitigation.