Hundreds of gallons of chemical foam used to fight fires have spilled out of the Army Aviation Support Facility and into the South Burlington wastewater treatment system, according to Vermont National Guard officials.
Col. Jacob Roy of the Vermont National Guard said work is underway to contain the spill and remove the foam from all affected areas.
“To our knowledge, it has not made it into any other water system,” he said in an interview. “So we will work directly with (the South Burlington water treatment plant) to ensure that we get everything cleaned up to satisfactory standards.”
The spill began around 9 or 10 p.m. Thursday, Roy said, when the building’s fire suppression system was set off by a mechanical failure. There is “no indication of a fire or any hazards that triggered it,” he said.
The 800 gallons of foam first spread through the building — located at the north end of the Burlington International Airport — and later moved through the building’s drainage system to the wastewater treatment plant, Roy said.
No one was at the aviation facility — which includes a hangar, aircraft maintenance areas, and administrative and classroom spaces — at the time of the spill, Roy said. It is unclear how much damage was done to the facility, he said, and a full investigation won’t be possible until the foam is removed.
The substance that was spilled, aqueous film-forming foam, is used to fight high-hazard flammable liquid fires. It is often found in areas where significant amounts of flammable liquids are regularly used, such as aircraft hangars, according to a report from the Interstate Technology and Regulatory Council.
The foam contains a group of synthetic chemicals called per- and polyfluoroalkyl substances. These chemicals, commonly known as PFAS, can have cancerous health effects on humans and wildlife, according to the report.
Foam spills can be more damaging to the environment than other chemical spills, according to the report, because PFAS cannot be removed from water using conventional wastewater treatment processes.
Robert Fischer, the water quality superintendent for South Burlington, said the spill won’t harm the wastewater treatment facility on Airport Parkway because staff have already stopped contaminated water from entering the parts of the system it could damage. The facility’s chemist has already tested water samples, Fischer said, and “everything is looking fine.”
“I don’t believe it’ll have much impact on the facility, or on the aquatic macroinvertebrates or fish in the river,” he said. “But it is a cancer causing agent, and it’s been released into the environment, so we can’t take this lightly.”
Fischer said he found out about the spill around 8 a.m. Friday when his staff noticed foam coming into the facility. Around the same time, he said, officials from the Vermont National Guard began to contain the spill and reported it to the state Department of Environmental Conservation.
The National Guard contracted Republic Services, a recycling and waste solutions company based in Williston, to lead the clean up, Fischer said. The company is using vactor trucks — or what Fisher describes as a “wet dry vac on wheels” — to vacuum up the foam and transport it to a toxic disposal area.
“(Republic Services officials) are actively retrieving the spill as best they can,” Fischer said. “And I made some operational changes here to compensate for everything. And that’s all we can do.”
Roy said the Vermont National Guard will release updates as more information about the progress of the clean up becomes available.