Navy contractors were scheduled Thursday to begin testing well water from homes around Naval Support Activity Mechanicsburg in Hampden Township as part of an ongoing investigation into hazardous chemicals known as PFAS.
The substances, a chemical family known as perfluoroalkyl and polyfluoroalkyl compounds, were previously used in a type of firefighting foam common to U.S. military bases.
In 2016, the Environmental Protection Agency issued a health advisory regarding two specific PFAS — perfluorooctanoic acid, or PFOA, and perfluorooctane sulfonic acid, or PFOS — finding that exposure of over 70 parts-per-trillion, either to one substance or the two in combination, is linked to developmental disabilities in children, hormonal imbalances, an increased risk for certain cancers and other health problems.
Testing at NSA Mechanicsburg is a comparatively small part of the military’s ongoing effort to track down PFAS exposure nationwide. High levels have most often been found in water supplies around bases where firefighting foam was frequently used to put out aircraft fires, which is not an issue at the Mechanicsburg naval depot.
“If we were a major airfield or something like that, we would’ve been a much higher priority,” said Cathy Mulhearn, the environmental director for NSA Mechanicsburg.
The depot’s fire department used to use the foam in training, but stopped doing so about 20 years ago, Mulhearn said. Since then, the foam has been used rarely and only for serious fires. A map of the base, which the Navy displayed during its public awareness event at the Park Inn on Wednesday night, showed every site of possible foam use, down to a lawn mower fire several years ago.
Runoff from the base generally flows northwest, according to Navy maps, with the initial testing area set in roughly a mile radius from the drainage zone.
The area encompasses about 2,500 homes, according to the Navy, but the vast majority of these get their water from a public utility, either the Pennsylvania American Water Co. or Suez Water. NSA Mechanicsburg itself also gets its on-base water from Pennsylvania American Water and Suez.
Only 95 homes are believed to use ground water from wells that could have PFAS exposure. Roughly half of these homeowners had responded to the Navy as of Wednesday night to schedule testing.
“If there is a problem, they’ll be on bottled water within 24 hours and we’ll go from there,” Navy spokesman Chris Cleaver said.
Long-term solutions, according to the EPA, would either be to hook up the affected owner to utility water, or to install an on-site filter for the home’s well in cases where utility lines can’t be run. The Navy would pay for this expense.
Foam and concerns
Joseph Woodward, an operations director for Pennsylvania American Water, said the utility has tested its water lines in the area and found PFAS levels nowhere near the 70 ppt limit. Water for customers in the area comes from one of two treatment plants, one of which draws water from the Conodoguinet Creek, and the other from the Yellow Breeches Creek, Woodward said. Neither site is in the exposure area for NSA Mechanicsburg.
It’s possible that the PFAS-containing foam was also used when the depot’s fire department was called out to assist in surrounding areas of Cumberland County.
Al Bienstock, president of the Hampden Township Board of Supervisors, said the municipality is working with surrounding fire companies to figure out what calls the Navy’s trucks responded to and where the foam may have been used, although records are limited.
The township’s volunteer fire department uses foam that doesn’t have PFAS, Bienstock said.
“At this point, it’s important enough to care about, but not to panic about,” he said.
Because the foam may have been used outside the military bases being tested by the U.S. Department of Defense, states — including Pennsylvania — have been taking action of their own.
Late last year, Gov. Tom Wolf announced the creation of a state task force on PFAS, which devised a plan to test 400 water sources across the state believed to be potential contamination sites.
These include areas around military bases, civilian airports, fire training sites, known locations of truck fires per PennDOT, and manufacturing plants for metal plating and electronics, processes that can cause PFAS contamination. PFAS can also be found in Teflon-based products and some clothing.
Because the chemicals weren’t previously classified by the EPA as hazardous, “we don’t know who’s been using the chemicals, and that’s part of the problem,” said Lisa Daniels, director of the Bureau of Safe Drinking Water for the state Department of Environmental Protection.
The wider issue is that the PFAS chemical family includes potentially thousands of compounds, Daniels said. The EPA advisory covers two, PFOA and PFOS, which are believed to be the most problematic because they have the longest half-life, and thus stay in the ground longer.
“There is still a lot of work going on to figure out if there should be a health advisory on the other chemicals,” Daniels said. “There’s less research available on those other chemicals.”
Pennsylvania officials have expressed dissatisfaction with the EPA’s research and regulatory pace. The 2016 advisory is just that, an advisory, and for the most part not legally binding.
Pennsylvania law allows the state to take some action based off a federal advisory, but most states want the EPA to issue an official regulation called a maximum contamination level, which would carry more legal power to require testing and remediation.
The state DEP and Department of Health are working with toxicologists to develop a state-level MCL, Daniels said, which is allowed by state law but has not been done before, since Pennsylvania typically just incorporates federal rulings.
“It’s the first time we’ve done it, but Gov. Wolf was just not comfortable with the idea that the EPA could take five to 10 years” to finalize an MCL, Daniels said.
Previous Department of Defense testing has identified several sites in Pennsylvania with elevated PFAS levels. In central Pennsylvania, this includes Letterkenny Army Depot near Chambersburg, as well as the Air National Guard site at Harrisburg International Airport near Middletown.