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More than 1,400 gallons of firefighting foam filled with toxic PFAS - forever chemicals - spilled into the environment when a fire suppression system at an airplane hangar in Maine went off by accident. As Nick Song from Maine Public reports, the incident brings up concerns about these older fire systems found in airport hangars throughout the U.S.
NICK SONG, BYLINE: David Page is a retired Bowdoin College chemistry professor. He lives only a few minutes away from the Brunswick Executive Airport, a former naval air base whose facilities are now rented out to businesses.
DAVID PAGE: That's Hangar 4 there, with the big doors.
SONG: Like other hangars of its size, Hangar 4 is required to have a fire suppression system. But in late August, Hangar 4's system accidentally discharged, filling the hangar and three aircraft inside with 4 to 5 feet of firefighting foam. It seeped into ponds and waterways nearby. Cleanup trucks with bright red chemical containers spent days vacuuming it up, but the area still revealed high levels of PFAS.
PAGE: There are a lot of drains that go into the stormwater system, which empties into a chain of ponds that we're headed up to right now. And I think - yeah, you can see there's a lot of activity. I think this is it.
SONG: This area already had high levels of contamination because of military activity around the site. Built in the '70s, Hangar 4 still has its original fire suppression system, which uses AFFF or aqueous film-forming foam. The product contains PFAS and has long been the industry standard for fire suppression in airplane hangars.
PAGE: Anywhere you have stored legacy firefighting foam concentrate in any form, you're going to have this problem, you know, potentially occur.
SONG: Matthew Klingle is the director of Bowdoin College's environmental studies program. He says the Navy and the 3M company invented the foam in the 1960s as a way to put out fuel-based fires.
MATTHEW KLINGLE: You've got a burning aircraft on the tarmac. You go out there, you spray it with this, it envelops it - this foam - and it puts out the fire just like that.
SONG: PFAS can seep into drinking water, be picked up by wildlife and exist almost indefinitely. Scientists have linked the chemicals to causing cancer and other serious health risks. Pierce Lushinsky designs fire suppression systems for hangars. He says many states have begun restricting the sale and nonemergency use of AFFF.
PIERCE LUSHINSKY: I know certain manufacturers are not even making the legacy foams anymore that contain PFAS.
SONG: Industry fire standards for airplane hangars changed in 2022 to encourage alternatives, but it may be challenging to phase these systems out. New foams without PFAS are out there, but Lushinsky says it's not an easy swap.
LUSHINSKY: You can't just take the old foam out of the tank and put the new foam in. They have very different physical material properties, so there's different equipment that is required to get those foams to flow and mix with the water and actually achieve the same performance as what the older legacy foams could attain.
SONG: Installation can cost hundreds of thousands of dollars, so many owners don't update their hangars' fire system until they're forced to do so by local building codes. And while industry safety standards are updated every few years, widespread adoption on the local level usually lagged behind.
LUSHINSKY: You know, if you're not being forced to replace it, if it works, why am I spending the money?
SONG: As a result, Lushinsky says there are hundreds of these legacy systems in hangars across the U.S. that have yet to be decommissioned. Beyond the chemicals, Professor Page says these legacy fire systems are unreliable.
PAGE: Virtually all of the discharges of foam have been accidental, and that's another reason why these systems are not really appropriate.
SONG: When these systems go off, it's almost always by accident. A report from the University of Maryland found that 99% of the time, there isn't even a fire, and these accidental releases are getting more frequent. They now happen, on average, about once a month.
For NPR News, I'm Nick Song. Transcript provided by NPR, Copyright NPR.
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