Delaware officials updated a list of sites where they are testing for so-called forever chemicals, naming 15 locations where aquifers supplying public water systems are being sampled for the toxic substances.
The sites include Red Clay Calf Run in New Castle County, Dover Air Force Base in Kent County, and Bayside at Selbyville in Sussex County. The list of sites also includes the Sussex County town of Blades where earlier testing of source water found a high PFAS content that was removed after treatment, according to the Department of Natural Resources and Environmental Control.
At each site, scientists are looking for chemicals including PFOA and PFOS, two of the most common kinds of PFAS which number in the thousands in total. PFAS are subject to increasingly strict regulations across the country amid gathering evidence of their links to serious illnesses including some cancers, immune and developmental problems, and elevated cholesterol.
The state is due to release overall results by the end of the year but any communities where the chemicals are found at levels that exceed local or national health standards are expected to be notified right away.
“It’s very important that no people are put at risk from drinking contaminated water,” said State Rep. Debra Heffernan (D-Brandywine Hundred), who was the chief sponsor of last year’s law to set enforceable standards for the two kinds of PFAS in Delaware. “So I believe they will make sure that if there is any emergency action that needs to take place, based on preliminary levels, that they will do that.
“It’s very important that no people are put at risk from drinking contaminated water. So I believe they will make sure that if there is any emergency action that needs to take place, based on preliminary levels, that they will do that."Debra Heffernan, Democratic State Rep.
“DPH and DNREC are charged with protecting our environment and protecting public health, and if they know that any residents are being exposed to harmful chemicals, they will have to make sure they’ll take action to make sure that nobody is exposed,” she said.
The sampling project is among the requirements set by HB 8, which was signed into law last October. The law also led to Delaware proposing its own health standards for PFOA and PFOS after years of following a federal guideline that many advocates for stricter standards said was too high to adequately protect public health.
In June, the U.S. Environmental Protection Agency published new “Health Advisory Values” for the two chemicals that were sharply lower than both its previous guideline, and the levels that Delaware officials proposed just three months earlier.
The Division of Public Health proposed PFOA in drinking water should be no higher than 21 parts per trillion (ppt) for PFOA and 14 ppt for PFOS. Those levels are much higher than the new levels of 0.004 ppt and 0.02 ppt, respectively, advocated – though not required – by the EPA.
If the EPA levels eventually become enforceable limits, Heffernan’s bill requires Delaware to adopt them if they are lower than the state-mandated standards.
But since the federal guidelines are only advisory for now, Delaware will adopt its own standards, Heffernan said.
The EPA’s level “is not an enforceable limit, and why I felt we needed our own enforceable limit, not waiting for EPA, was because we need a goal,” she said.
The big difference between the state and federal levels shows that Delaware needs to ensure that whatever health levels – formally known as Maximum Contaminant Limits or MCLs – the state chooses to adopt are truly protective of public health, including sensitive populations like young children, Heffernan said.
“What it shows for Delaware is that what we need to do is to re-evaluate on a periodic basis, maybe yearly, to make sure our levels in the state are protective of human health, and we need to make sure we are looking at all the new data,” she said.
Dustyn Thompson, director of the Delaware Sierra Club, urged officials to explain why the federal advisory limit is so much stricter than Delaware’s proposed regulation.
“What’s the reason for the discrepancy and what are we going to do about the discrepancy?” Thompson asked.
The number and location of sites in DNREC’s updated list shows that “they clearly understand the problem,” Thompson said. “They know where the danger zones are. They are clearly not cherry-picking areas that are not going to come back with PFAS contamination.”
He cited the Sussex County town of Blades – where PFAS chemicals have already been detected in public water – and the Dover Air Force Base, as chemical hotspots where more remediation may be needed.
The current sampling program will add to understanding of the status of PFAS in Delaware after testing by the U.S. Geological Survey in December 2018 found PFAS in 16 out of 30 public water systems across the state.
Two of the wells tested by USGS exceeded the old federal standard, and others topped much stricter standards set by New Jersey, a national leader in PFAS regulation that some advocates have said should be a template for Delaware’s efforts to regulate the chemicals.
In the current testing program, the number and spread of sites confirms that PFAS – formally known as per- and polyfluoroalkyl substances -- are a widespread problem and a threat to public health in Delaware, Heffernan said.
“The list points to what we know, is that PFAS is a pervasive statewide problem in ground water, drinking water and surface water,” she said. “I’m not surprised at the number of sites because I know it’s a statewide problem.”
Heffernan said she’s trying to get more information from DNREC on how the sites were chosen.
“I am glad to see that EPA has set the most stringent health advisory levels possible, one cannot be too careful with the health of the public. And Delaware is setting drinking water standards for these carbon fluorine compounds that are some of the most protective in the nation.”Dr. Jerry Kauffman, Director of the University of Delaware’s Water Resources Center
The man-made chemicals have been used in a wide range of consumer products including non-stick cookware, carpets, clothes and paint since the 1940s. They don’t break down in the environment – explaining their nickname ‘forever chemicals’ – and accumulate in the human body where they can cause a range of serious health conditions including reduced fertility and decreased vaccine response.
Contamination of drinking water sources with PFAS is especially widespread on military bases, including Dover Air Force Base, where firefighting foam containing the heat-resistant chemicals was used for years, and washed off into aquifers.
The widespread use and stability of the chemicals means that most people have been exposed to them, largely through drinking water or food, DNREC said in a work plan on the testing program.
In October last year, the agency began to sample residential drinking water wells that had been impacted by PFAS from aquifers.
Dr. Jerry Kauffman, Director of the University of Delaware’s Water Resources Center, welcomed the updated testing program, as well as the tough federal standards.
“I am glad to see that EPA has set the most stringent health advisory levels possible, one cannot be too careful with the health of the public,” he said. “And Delaware is setting drinking water standards for these carbon fluorine compounds that are some of the most protective in the nation.”
