Well Testing Reveals PFAS Contamination At Polpis Property

Two more private wells on Nantucket have tested above the state’s public drinking water standard for the so-called “forever chemicals” known as PFAS. One well, located on Bassett Road in Polpis, isn’t near any previous wells that have tested above the 20 parts per trillion (ppt) standard, also known as the Massachusetts Maximum Contaminant Level (MMCL), providing further evidence that the pattern of contamination is far more widespread than initially thought.

“This, you know, frankly, was not a place we expected to see PFAS contamination, so it really speaks to the importance of getting your well tested,” town environmental contamination coordinator Andrew Shapero said. “We should by no means consider the extent of PFAS contamination on the island to be delineated. We should expect that we're going to get more detects, unfortunately, and so we really need to be getting the word out.”

The test result comes on the heels of multiple tests conducted by the Massachusetts Department of the Environment (MassDEP) that showed PFAS levels so high they exceeded the state’s imminent hazard threshold of 90 ppt. The wells with imminent hazard detections were also outside of known hotspots, but far from the new detection in Polpis.

Shapero announced the Polpis detection as a part of a review of the Nantucket Health Department’s PFAS testing efforts at a Board of Health meeting last Thursday. Since May, the Health Department has had 46 tests come back as non-detects. Eighteen tests detected some PFAS, but not enough to exceed the MMCL.

The other test that exceeded the MMCL was conducted on a well on Thurstons Way, near Miacomet.

“There is PFAS throughout the island, and the source of much of that is unknown, unfortunately, which is scary,” Shapero said.

It remains unclear where much of the PFAS in island wells is coming from, where it might be detected next, or why tests conducted in the same geographic area are yielding dramatically different results.

“I just think that this is a little scary how much bigger it is getting,” Board of Health vice chair Meredith Lepore said. “It looks like we don't really have a handle on the plume at all—or multiple plumes. I mean, this is a huge health hazard and concern for our community.”

However, there are some theories why wells in the same geographic area might have dramatically different results. One is groundwater flows: if the water is travelling in a certain direction beneath the surface, a well upstream of the flow, even if it is very close to a contaminated well, might be safe.

“If you’re downstream of a source, you may have much, much higher levels,” Brad Campbell, the President of the Conservation Law Foundation, told the Current. Campbell is involved in legislative efforts to combat PFAS contamination, including in Massachusetts, where he champions efforts to expand private well testing for PFAS.

The other theory is well depth. If PFAS enters the aquifer through leaching in the soil, it may affect shallower wells more acutely.

“To some extent, I do think that well depth matters quite a bit,” Shapero said. “That might be one explanation of why we are seeing such different results over small areas. It has something to do with what's going on underground. Whether that's groundwater flows or it's well depth kind of remains to be seen.”

Sampling efforts by MassDEP and the Nantucket Health Department continue, and Shapero has repeatedly urged private well owners to test their wells.

PFAS contamination is a widespread issue throughout the country. Shapero and Campbell both referenced a study by the United States Geological Survey that found roughly 45% of US drinking water is contaminated with some amount of PFAS.

“This is a public health threat to the people of Nantucket, but it is also a public health threat to much of the entire country,” Shapero said. “If you are thinking of moving somewhere else because of PFAS, you might be in for a rude awakening.”

But that doesn’t mean that the issue is any less serious. Even low detections, below the MMCL, are still cause for concern.

“No level of PFAS is safe in your drinking water. So it’s important that people be aware and that people test,” Campbell said.

Used to manufacture stain- and water-resistant products, the family of chemicals known as PFAS is suspected to increase the risk of kidney and testicular cancers, as well as other health conditions. They are often referred to as "forever chemicals" because they do not break down and persist in the environment. The chemicals are used in a wide range of products, from non-stick pans to fast food wrappers to firefighting foam.