Public briefed on PFAS contamination

Further study needed to formulate regulatory standards.

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Ron Myrick of Tetra Tech briefed the public on the airport's PFAS investigation and proposed remediation plans. - Lucas Thors

Updated Jan. 31

Members of the public met with Ron Myrick of Tetra Tech to get information regarding per- and polyfluoroalkyl substances (PFAS), and measures to mitigate further contamination of groundwater and soil.

Residents of roads like Coffins Field, Waldrons Bottom Road, and Vineyard Meadow Farms who live south of the airport were in attendance at the meeting in the MVY terminal. The audience of around 20 people also included airport commissioners and other members of local government.

After initial tests, 26 wells on those roads have tested positive for PFAS, with 13 of them being at or above the 70 parts per trillion guideline set by environmental regulators. Many of the homes are getting bottled water while the airport consultant works on plans to install carbon-based filtration systems for some of the properties.

PFAS is a chemical compound used for fighting Class B petroleum fires, often involved in aircraft. Myrick said the chemical is mixed with water and other compounds, then administered as a foam that smothers petroleum fires.

Myrick told Islanders regulatory standards for PFAS and other long-chain compounds have yet to be determined, and Tetra Tech is still gathering information about toxicity levels and ways of containing and disposing of the chemicals.

“PFAS is still an emerging contaminant,” Myrick said. “We are going to be sending information to the Massachusetts Department of Environmental Protection [MassDEP] on a monthly basis, and hopefully soon there will be well-defined standards for dealing with PFAS.”

Myrick presented a response action plan that will monitor PFAS presence in wells, groundwater, and soil, and contain chemicals that have already been dispersed.

The health advisory provided by the MassDEP dictates 70 ppt as the regulatory limit for PFAS content, but Myrick said properties with wells testing higher than 20 ppt are being offered bottled water and a filtration system, if necessary.

Chairman of the airport commission Bob Rosenbaum asked Myrick if precautions can be taken at home to prevent consuming contaminated water, such as boiling a pot of water to be used for drinking.

Myrick said that because the chemicals are water-soluble, boiling water will actually make the concentration higher. “By boiling water, you are taking away water as it evaporates, while the chemicals stay in the pot,” Myrick said. “So if you start with a full pot of water and end with a half pot, you have effectively doubled the chemical concentration.”

Myrick also gave background information on PFAS and the history of its use. PFAS has been manufactured since the 1940s. Its unique physical and chemical properties impart oil and water repellency, temperature resistance, and friction reduction to a broad range of consumer products. You may find PFAS in nonstick cookware, waterproof coatings for textiles and paper products, and various electronics.

The compound is resistant to degradation, so it persists in the natural world and even within our bodies, Myrick said.

“These chemicals are everywhere — they have been for a long time — It was only until recently that you could even test for them,” he said. “They aren’t just in water, they are in the food we eat.”

Long periods of exposure to PFAS, or high concentrations of it, are toxic and can affect developing fetuses, thyroid, liver, kidneys, hormone levels, and the immune system. The chemicals have also been known to create a cancer risk, Myrick said.

Myrick explained how the aqueous film-forming foam substances (AFFF) spread through soil and groundwater and into private wells.

“The chemicals that get into the groundwater are not the foam itself,” Myrick said. “The AFFF foam dissolves, and the chemicals are diluted with rainwater, then they can enter storm drain systems.”

Since the topography of Martha’s Vineyard is far from flat, Myrick said the direction of groundwater flow is difficult to predict. This means the scope of testing for PFAS contamination must be larger.

“We are going to be looking at lots of areas. If we think there might be some contamination, we will do a preliminary test,” Myrick said. “If we find PFAS above guideline levels, we will figure out the best way to remove it.”

Private wells around the Island are dug at different depths, which means some wells in the same area may encounter different levels of contamination.

Myrick said Tetra Tech is testing wells at various depths to determine where higher concentrations of the chemicals are located.

In the near future, Myrick said he would keep communication open with affected households and continue to monitor PFAS levels.

Hopefully, Myrick said, MassDEP will draft regulatory standards by winter of 2019 dictating risk-based standards, and by that time, another public session can be held to provide new information.

PFAS expert Dr. Wendy Heiger-Bernays has also been hired through a federal grant to conduct a toxicity and risk assessment report. Email Heiger-Bernays at whb@bu.edu with any questions, or call 617-358-2431.

Myrick is also available at ron.myrick@tetratech.com, or at 508-786-2363.

Updated to provide more details from Wednesday’s meeting. -Ed.