West Tisbury investigates PFAS contamination

West Tisbury is co-operating with the state’s Department of Environmental Protection to investigate a private well contaminated with per- and polyfluoroalkyl substances (PFAS). 

According to West Tisbury health agent Omar Johnson, the testing was handled by the state. The well tested 50 parts per trillion for PFAS, when the state’s recommended amount is 20 parts per trillion. The resident living in the contaminated area was advised to get a water filter for the home.

WCAI reported earlier this month that other private wells on the Cape and Islands were also contaminated with PFAS.

“There have not been any other detects [in West Tisbury] at this point,” Johnson said. “We’re still in the process of reaching out. Not only to everyone in the vicinity, but in other areas we think might be of concern.”

Johnson listed the fire station, the public safety building, the schools in town, and neighbors near the West Tisbury dump as places he encouraged to get tested. He said the people in these areas are following or plan to follow his recommendation, and are requesting PFAS testing kits from the state. The state has allocated 40 tests to West Tisbury, according to Johnson. 

Johnson said he has been working closely with Angela Gallagher from DEP and West Tisbury Fire Chief Greg Pachico to look at the PFAS situation in West Tisbury. Johnson has gone door to door to the residents near the contaminated area, to warn them about the issue. 

West Tisbury’s town hall, public library, and school have been tested so far, and have not shown PFAS detection, according to Johnson. 

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.

“I’m just trying to be thorough,” Johnson said. The PFAS testing program in West Tisbury has been going on for about a month and a half now. 

So far, it is uncertain where the PFAS originated. 

This is not the first time PFAS has been discovered in private wells on the Island. In 2018, PFAS contaminants, believed to be from firefighting foam used at Martha’s Vineyard Airport, were discovered in neighborhoods south of the airport.

The airport has paid to have filtration systems installed on wells where PFAS compounds were found at concentrations above 20 parts per trillion. The airport has worked with Tetra Tech, an environmental engineering company, to periodically test the wells, as well as sample wells drilled to monitor for PFAS in the groundwater.

Tetra Tech is planning to do a comprehensive site assessment at the end of 2022 to investigate the potential spread of PFAS into the groundwater and soil.

Meanwhile, the airport, which is still required by the Federal Aviation Administration to use firefighting foam, has installed a system to contain the contaminants during training exercises.

Johnson said the current incident is “highly unlikely” to have a connection to the airport, because of the distance from the detect. 

“It could be an isolated incident, but that has not been determined yet,” Johnson said. “DEP is still doing their testing and investigation … I’m still waiting to see a broad picture of the extent of the contamination.” 

Detecting the source of PFAS can be difficult because the chemical compounds are found in nonstick cookware, waterproof coatings for textiles and paper products, and various electronics.

Although there is a possibility of PFAS spreading through the Island’s natural and artificial water systems, Johnson said, without further testing it is unclear how much of a factor this is.