Most parts of Delaware now have drinking water that meets strict new federal health limits for toxic ‘forever chemicals’ but a few places exceeded the limits when they were tested over the last year, and some residents worry that they are still vulnerable to illnesses linked with the chemicals because they drank the water long before PFAS became a public-health concern.
Recent data from the U.S. Environmental Protection Agency shows that only 6 percent of 3,172 samples taken from public water systems around the state in 2023 and 2024 contained PFAS chemicals. But a smaller share of samples – 2.5 percent – showed PFAS at a higher level that some experts say threatens public health.
Dr. Jerry Kauffman, director of the University of Delaware’s Water Resources Center, and a long-time advocate for strict health limits on PFAS in drinking water, called the 6 percent level for any PFAS presence “reassuring” but said the 2.5 percent of samples showing the chemicals above 14-21 parts per trillion (ppt) are “an urgent cause for concern.”
Those locations include a sample taken at Suez Water’s Stanton plant on Oct. 26, 2023 when PFOA, one of six PFAS chemicals now regulated by the EPA, was found at 24.4 ppt, according to the data from a continuing national series of tests called the Uncontaminated Monitoring Rule 5 (UCMR5). The same chemical was found at 23.1 ppt in an Artesian Water well at Caravel Farms on May 6, 2024.
In April, the EPA finalized regulations that set an unexpectedly strict 4 ppt national limit for the chemicals PFOS and PFOA in drinking water but gave utilities until 2029 to install filters that would allow them to comply. In a landmark action that marked the first national regulation of ‘forever chemicals’, the agency also set strict health limits for four other commonly occurring chemicals in the class. By 2029, utilities are also required to tell the public about any parts of their systems that don’t meet the PFAS standards.
The federal action followed regulations by some states in response to growing public concern that the chemicals were linked an array of illnesses including some cancers, ulcerative colitis, elevated cholesterol, impaired immune response to vaccines, and developmental problems in young children. Delaware was poised to set its own limits, as specified by a state law in 2021, but will now comply with the federal standards because they require stricter standards than the state law would have done.
State Rep. Debra Heffernan, lead sponsor of the bill, said most Delawareans are now protected from the regulated PFAS chemicals in drinking water but are still exposed via many other products such as some food packaging that use the chemicals.
“People are getting exposure not just from drinking water but from so many sources. Even if every water system meets this MCL people would still have exposure to these contaminants from other sources."Democratic State Rep. Debra Heffernan believes that most Delawareans are still exposed to PFAS chemicals outside of just drinking water.
“People are getting exposure not just from drinking water but from so many sources. Even if every water system meets this MCL people would still have exposure to these contaminants from other sources,” said Heffernan, an environmental toxicologist in her professional life.
State officials acknowledged that PFAS remains present in some water systems, but said they aren’t yet able to quantify the number of systems or the degree of contamination because the tests are not complete.
“The UCMR5 data is illustrating some presence of PFAS in drinking water in some of our systems,” said Sandi Spiegel, environmental health director for the Division of Public Health. “The extent is not completely identified, nor is how severe it might be. We’re getting that data now, and we’re providing funding for the monitoring and sampling so that we can identify how to best help the public-water treatment systems put in mitigation to remove PFAS from drinking water.”
But Spiegel said officials have identified systems with the greatest need for PFAS mitigation, and the state is applying for federal funding to help them.
DHSS and DNREC work together to respond to PFAS in drinking water. That includes providing funding to water systems and reaching out to disadvantaged communities who are on private wells, providing free in-home treatment where warranted.
For homes with private wells where officials find PFOA and PFOS at above the EPA’s new health levels, the agencies provide point-of-use mitigation, said Todd Keyser, a hydrologist with DNREC’s Division of Waste and Hazardous Substances.
Whether a homeowner is served by a public system or a private well where PFAS is found, he or she can add a filter to their home plumbing such as a carbon filter with reverse osmosis, which cost in the range of $1,000 to $6,000, Spiegel said.

For public water systems, the cost of installing filtration is much higher, and will result in a steep statewide bill for protecting the public from PFAS in drinking water. Spiegel said she has seen funding requests from utilities for $200,000 up to $90 million. “The cost of effectively mitigating PFAS is going to be an expensive lift,” she said.
While the federal data show most Delaware drinking water systems now meet the new health standards, state testing of surface water indicates that PFAS is still a problem in some water bodies. A recent DNREC report on testing of 83 samples around the state in 2022 found PFAS in six creeks that warranted further investigation.
And private wells, from which about 200,000 people, or a fifth of Delaware’s population, get their drinking water, are not regulated, said UD’s Kauffman. Those wells are exposed to possible PFAS contamination unless their owners install the right filters.
Meanwhile, water utilities that have PFAS in their untreated water at above the federal health limits have either installed filters, or are in the process of doing so, Kauffman said. Those that have already installed the filters include the investor-owned Artesian Water that supplies water to some 300,000 people in all three Delaware counties, and the much smaller New Castle Municipal Services Commission serving about 2,200 residents.
Other utilities include the City of Newark’s South Wellfield and Veolia Delaware that are expected to start operating their new filtration in 2025, while some utilities with double-digit PFAS levels will be “racing” to install filters, helped by unprecedented federal infrastructure funding, Kauffman said.
Testing for PFAS at public water systems around the U.S. has been conducted by certified EPA contractors including Delaware-based PFAS Solutions, a nonprofit. Its president, Seetha Coleman-Kummala, called the EPA’s new PFAS limits “shockingly low” but said they are needed to protect public health from chemicals that are linked to a long list of serious illnesses.
“Would I like to drink water that’s more than four parts per trillion?” she asked. “No, if I have a choice. We have a grandchild. Would I like to mix his formula with water above the limit? No. I think this is a dilemma that’s in front of us.”
Still, Coleman-Kummala predicted that some people will continue to drink water that exceeds the new EPA limits for PFOA, PFOS, and the other four regulated chemicals for up to five more years until the limits become effective.
It will take time and money to install the right filtration, and most water suppliers will have to do so because the limits are so low, she said.
But Coleman-Kummala urged people not to panic, and not to lose confidence in public water supplies that mostly already meet the new EPA limits.
“If people lose confidence in the quality of the drinking water, they are going to go to bottled water... It really is important that people don’t panic, and that we all act with a level head."Delaware-based PFAS Solutions president Seetha Coleman-Kummala advises people not to lose confidence in public water supplies.
“If people lose confidence in the quality of the drinking water, they are going to go to bottled water, and trust me, bottled water has a much higher carbon footprint and creates plastic waste. It really is important that people don’t panic, and that we all act with a level head,” she said.
In New Castle, the city-owned utility installed PFAS filters on its wells starting in 2014 after finding PFOA and PFOS in its untreated water at levels that were sharply higher than the health guidelines then set by the EPA, and even higher than the new enforceable limits. The city’s water has met the federal standards since then, and officials aim for a “non-detect” level for each of them, said Jay Guyer, the commission’s Water Utility Manager.
He said there are no firm conclusions about the source of the contamination but there has been speculation that it originated from the nearby Air National Guard Base where the military – as it did at many other bases around the country -- used fire-fighting foam containing PFAS, which then washed into aquifers and has remained there for decades. In 2014, PFAS chemicals were found in groundwater near the base, and in two nearby water systems at levels exceeding federal guidelines at the time, according to the U.S. Agency for Toxic Substances and Disease Control.
Even if their water is now free of PFAS, some New Castle residents worry that they previously consumed PFAS without suspecting it, and may now be exposed to illnesses that are linked to the ‘forever chemicals’ – so-named because they don’t break down in the environment, and accumulate in the body long after their use or production has ended.
Gene and Joanne Small lived less than a mile from the base for 44 years until 2014, and raised their two children there. Now Gene, 86, has a series of illnesses including kidney disease, congestive heart failure, and cirrhosis of the liver even though he was never a heavy drinker. He had part of his thyroid gland removed because of a goiter that had grown there, while his daughter who now lives in Arizona had thyroid cancer.
Gene has no proof that any of the conditions is related to PFAS in his water, and none of his doctors have linked the two, but now that he knows the aquifer beneath the air base was contaminated with PFAS, he wonders whether that was the cause.
“Well, something had to cause it; not sure what it is,” Small said in an interview at a New Castle apartment where the couple moved in 2014. “I don’t have any medical proof but it very well could be a cause. For fear of lawsuits and everything else, a doctor is not going to give you a definite unless he has that right there on paper to prove it.”

In 2019, the couple had their blood and urine tested for PFAS as part of a national survey by the Centers for Disease Control of people who live near current or former military bases that had the chemicals in their drinking water. They were among 214 participating New Castle County residents in 134 households.
For Joanne, now 82, the tests showed three kinds of PFAS in her system at well above the national average levels, while Gene’s readings were below the average for most of the chemicals tested.
“I can just imagine how much of the U.S. population has all these problems, and have no clue where it came from,” Joanne said.
Their house near the air base had a filter supplied by Artesian to treat for hard water but not for PFAS. The company did not respond to a request for comment.
At Asbury United Methodist Church, just across Route 13 from the air base, Pastor Tracy Mooney said she has been saddened by what seems to be high rates of illness and death among church members during her eight years there.
Fifty-three congregants have died since 2016, and although many were elderly, Mooney wonders if their illnesses had anything to do with PFAS. Possible sources include nearby sites identified by DNREC, or the nearby East Basin Road Groundwater Site, a Superfund site where PFAS and other contaminants were found, leading to its designation to the National Priorities List in 2023.
“We have no proof of anything nor could I tell you whether they wouldn’t have gotten the same condition if the water wasn’t contaminated. All I know is that for years the water was highly contaminated,” she said.
In their report on the 2019 PFAS testing, the CDC/ATSDR said the maximum concentrations of PFOS and PFOA in the New Castle municipal system were 2,300 ppt and 440 ppt, respectively. In the Artesian system, those chemicals were found at a maximum of 1,800 ppt and 140 ppt, respectively. All the levels were dramatically higher than either the past federal health guidelines or the current enforceable limits. Both utilities “mitigated” the contamination in 2014, the CDC said.
“It drained me,” Mooney said. “Then I started looking into it, and found that six out of 15 sites sampled by DNREC were here in New Castle. I thought, ‘Well that’s weird. Out of all of Delaware, six of them were in a three-mile area.’ So then I started looking into it, and I find out there’s an EPA Superfund site. It seemed that something’s up here. Maybe the health issues we have here are connected to this.”
Rollin Shepheard, one of Mooney’s congregants, has lived nearly all of his 62 years in New Castle, and still lives in the Penn Acres development where Gene and Joanne Small lived until 2014. He’s unaware of any problem with his own health but recalls growing up drinking public water without a thought that it might be contaminated, and now wonders if he had been drinking PFAS all along.
“As a child in New Castle area, all we had to drink was water, and we drank lots of it; there was no money for sodas. It’s a major concern,” he said.
One of Shepheard’s two daughters – who was raised in the neighborhood and now lives with her family a few blocks away – has complications from diabetes, while one of his brothers has recently been diagnosed with colorectal cancer, he said. Another brother, 16 years older, died of bone marrow cancer.
“I’ve lived here for almost 40 years in this neighborhood. I’ve actually seen lots of neighbors pass away from cancer,” said Shepheard, a retired telecommunications systems engineer.
Kathy Wayne, another member of the church, faulted the State of Delaware for not doing more to educate the public about PFAS and other contaminants in the environment.
“Does anybody know that they should be testing their water? There’s [a] lack of education; there’s [a] lack of information to the general public. Yes, people are aware of what PFAS are, and that it could affect them but then it stops."Kathy Wayne, a member of Asbury United Methodist Church, doesn't think Delaware is doing enough to educate the public about PFAS and other contaminants.
“Does anybody know that they should be testing their water?” Wayne asked. “There’s lack of education; there’s lack of information to the general public. Yes, people are aware of what PFAS are, and that it could affect them but then it stops. They don’t know where to go or how to proceed because nobody has communicated with them. I think the government has done a poor job, and especially here in Delaware because there are so many chemical companies.”
In Kent County, PFAS chemicals were found in an aquifer beneath Dover Air Force Base thousands of times above health limits in some places in tests starting in 2016. The chemicals are still present on base, and at three off-base locations, a base spokesperson said in an email in mid-October.
“Although we previously sampled the properties around the site, we are preparing to resample the properties that had some level of contamination,” said Christina Camp, the spokesperson. “This will give us a current site picture of possible migration of PFAS off-base.”
Until now, the military’s PFAS actions at Dover have included the installation of Point of Entry Systems (POETS) at nearby properties that have been affected by use of PFAS on the base; an agreement with the City of Dover to add impacted properties to the city water supply, and a remedial investigation into the extent of PFAS in soil and groundwater under the federal Superfund Act.
Nine so-called POETS systems were installed on private off-base properties within six months of the DoD’s response plan for affected properties, and the systems have been “highly effective” in removing PFAS from drinking water, the Air Force said.
The military is also planning to replace two drinking water wells for off-base properties by drilling into a deeper aquifer where the chemicals have not been detected.
“Most wells in the surrounding area are in a deep, confined aquifer, which limits PFAS impacts,” Camp said. “For impacted wells located in the shallow, surficial aquifer, the Air Force installed treatment systems, and we are assessing possible long-term solutions” including deeper wells in confined aquifers or connecting to municipal systems."