Delaware Public Media

Chemical contamination at Dover base 254,000 times higher than proposed federal limit, study says

Oct 12, 2018

Contamination by toxic PFAS chemicals in ground water at Dover Air Force Base was dramatically higher than federal health limits recommended this year, according to a new analysis from the Union of Concerned Scientists.


The nonprofit compared previously reported testing by the Department of Defense with new proposals on PFAS limits by the Agency for Toxic Substances and Disease Registry, and found contamination by two of the chemicals – PFOA and PFOS – on the base was as high as 2.8 million parts per trillion (ppt), or 254,000 times what the agency deems safe to protect public health.

The results, based on testing in 2016, gave DAFB the fourth-highest level of the two chemicals among 131 U.S. military bases covered by the analysis.

Recognizing that the contamination in water sources can spread to surrounding areas outside military bases, the study noted that there are some 42,000 people who live within three miles of the Dover base.

The UCS study also covered the New Castle Air National Guard Base near Wilmington, where the two chemicals were found at up to 758 times the ATSDR limit. And at the Marine Corps Reserve Training Center, also at Wilmington, the contamination was 176 times greater than the agency recommended.

You can see the UCS' interactive map of contamination at military bases here.

Military bases such as DAFB are hotspots for PFAS contamination because they have used firefighting foam containing the chemicals for years. The chemicals have washed into ground water, and have affected public water systems and private wells in some places.

An interactive map from the Union of Concerned Scientists shows Dover on its list of military bases with high levels of PFAS contamination.
Credit Union of Concerned Scientists

The man-made chemicals, formally called Per- and Polyfluoroalkyl Substances, are linked to illnesses including kidney and testicular cancer, ulcerative colitis, thyroid disease and elevated cholesterol, and are the subject of growing concern by environmental campaigners, nonprofits, and officials in some states.

“As scientific evidence linking PFAS with adverse effects on human health grows, so too does evidence of widespread environmental contamination and human exposure to these chemicals, sometimes at alarming concentrations, especially at or near U.S. military installations,” the UCS report said.

According to the U.S. Environmental Protection Agency, the chemicals are present in some local drinking water supplies, some food packaging, consumer products such as cleaning products and paints, and living organisms such as fish.

In 2016, the EPA set a non-enforceable health advisory limit of 70 ppt for the two chemicals, but campaigners say that’s far too high to protect public health, so they welcomed the June release of the ATSDR report which proposed limits that were seven to 10 times stricter than the EPA’s.

The gulf between the two sets of recommendations surfaced earlier this year in published emails between unnamed EPA and White House officials, urging ATSDR not to release its report because it would cause officials a “public relations nightmare” if they had to explain the difference.

Still, the EPA showed an awareness of public concern on the issue this year, holding a national listening tour of contaminated sites, and promising to look at whether it’s necessary to regulate PFOA and PFOS at a national level.

But campaigners say that even if the EPA decides to set enforceable national standards, it will be years before they become effective, and that local action is imperative to protect the public as soon as possible.

“The concentration of PFAS in the groundwater at Dover is alarming,” said Tracy Carluccio, deputy director of the environmental group Delaware Riverkeeper Network, and a longtime advocate for tighter controls on the chemicals. “These are some of the highest concentrations on the nation. With levels that high, it's clear that release of the compounds has been enormous and testing of drinking water wells in the region needs to occur immediately.

“People could be drinking water contaminated with very high concentrations of these toxic chemicals if their water source is connected to the groundwater pollution plume and they aren't even aware of the threat,” Carluccio said.

She urged the military to stop using firefighting foam that contains the chemicals, and to proactively clean up the existing contamination – which does not naturally break down in the environment. The tight restrictions being advocated by ATSDR and others now being implemented by New Jersey are authoritative benchmarks that the DoD should adopt rather than following the EPA’s advisory limits, she said.

Captain Ashleigh Peck, a spokeswoman for the base, said only one ground water sample was found with a PFOS/PFOA concentration of 2.8 million parts per trillion, and that 290,000 ppt was “more consistent” with other sample collected in the area.

The lower level of 290,000 ppt is some 26,000 times higher than the 11 ppt recommended by ATSDR.

The base converted to a different type of fire fighting foam in its emergency-response vehicles and fire suppression systems in two hangars between 2016 and 2018, she said. The new foam is PFOS free and contains only trace amounts of PFOA.

Peck said neither of the chemicals was detected in any municipal wells either on- or off-base.

“Although PFOS and PFOA are unregulated chemicals that are found in many household products, the Air Force is using a comprehensive approach - identify, respond, prevent - to address the potential for PFOS/PFOA contamination of drinking water, and respond appropriately,” Peck said in a statement.

Nationally, the military has joined the calls for federal regulation of PFAS, saying that it can’t effectively manage the problem without having a single standard for each chemical to comply with.

“EPA must go through the process to establish a maximum contaminant limit under the Safe Drinking Water Act,” said Maureen Sullivan, Deputy Assistant Secretary of Defense for Environment, Safety & Occupational Health, at a presentation to Congress in March this year.

She said the military has begun to remove firefighting foam containing the chemicals from the supply chain, and has made “great strides” in ensuring clean drinking water at its bases.

As of August 2017, the military found the chemicals in 564 public or private water systems outside military bases, among 2,445 tested, Sullivan said. At Dover, one private well was found with the two chemicals above the EPA’s advisory level, DoD data show.

But UCS says the military has not done enough to protect its own personnel, and people who live near bases, from the chemicals. Although some commercial airports have stopped using foam containing PFAS, and the military is looking for alternatives, it has not yet eliminated them.

The military’s efforts to curb the chemicals have been limited by the fact that it measures contamination by the EPA’s standard which underestimates the threat to human health, UCS said.

“While several approved sites have PFAS levels lower than the EPA’s voluntary limit, they may have higher PFAS levels than the ATSDR report suggests are safe,” it said.

Concern about whether the EPA standard properly protects public health, and the distant prospect of any federal regulation, has led some states to set standards that are much stricter than the EPA’s.

New Jersey, for example, is now implementing its first regulation for a PFAS chemical – PFNA – and is weighing tough new standards on PFOA and PFOS that would give the state some of the strictest limits in the country. In Pennsylvania, which follows the EPA’s standards for PFOA and PFOS, Gov. Tom Wolf recently formed an “action team” to manage the issue, and recommend ways of curbing contamination in response to what he said was the absence of federal leadership.

Delaware, too, follows the EPA’s guidelines for PFOS and PFOA, and since 2015 has listed them as hazardous substances under the state’s Hazardous Substance Cleanup Act, said Michael Globetti, a spokesman for the Department of Natural Resources and Environmental Control.

But the state believes the EPA should regulate the chemicals nationally, and has urged it to do so, said Andrea Wojcik of the Office of Health and Risk Communication at the Delaware Department of Health and Social Services.

“Delaware has formally issued concerns to EPA regarding the lack of a regulatory structure for PFAS compounds in public drinking water and has implored them to expedite the process to create one,” Wojcik said.

Despite concern that contamination at the base may affect public water systems or private wells outside it, there are no indications now that any nearby residents are drinking bottled water or treating their systems for PFAS, she said.

She said the DoD samples that showed high PFAS levels were taken from shallow monitoring wells on the base that do not supply water to off-base homes. The results are early warning signs that further testing is warranted, and that is due late this year or in early 2019, she said.

“Without results showing any exceedances of the Health Advisory Level for PFOS/PFOA exist, there is no recommendation for homeowners or public water system owners to take either action at this time,” she said.