Trace levels of harmful ‘forever chemicals’ found in Unalaska’s drinking water
According to a recent report from Unalaska’s Department of Public Utilities, some of the island’s drinking water contains traces of the harmful “forever chemicals” known as PFAS.
Per- and polyfluoroalkyl substances, or PFAS, refers to thousands of different kinds of man-made chemicals. The contaminants have been around since the 1940s and have recently become a popular topic within the media, after the U.S. Geological Survey released a study in early July saying at least 45% of U.S. tap water could contain one or more types of the PFAS chemicals. In addition, the U.S. Environmental Protection Agency has said that even small amounts in drinking water could pose health risks like decreased birth weight and cancer.
Unalaska’s Director of Public Utilities, Steve Tompkins, said PFAS were detected at one of the city’s three wells in very low amounts: 1.25 parts per trillion.
“It's a very low level,” Tompkins said. “And if we would have tested at the tap — because we usually run all three wells at the same time, and they blend and then they go to the consumer — it would have been below detection.”
PFAS are found all over the place: in shampoos, firefighting foams, ski wax. And they sometimes end up in drinking water and build up in the body.
For several years, the EPA said negative health effects could occur from water with contamination levels of 70 parts per trillion. But last year, they released a health advisory saying even small amounts — at just 4 parts per trillion — can be harmful.
The city isn’t required to test the water for PFAS, according to Tompkins. And the amount they found on the island is so low that it might not even be detected next time they test.
While Tompkins said it’s important to know the forever chemicals are there, the results also complicate things.
“It causes more questions than answers because you do wonder, ‘what is in that area?’” he said.
Well number 2 — where the PFAS were found — is located in Unalaska’s Valley, across from the Qawalangin Tribe office. Tompkins said the history of military presence in the area may be the cause of the contamination.
The Army Corps of Engineers is nearing completion of a decades-long cleanup project of diesel contaminated soil in the Valley. The Valley is one of several locations in Unalaska where the military buried diesel storage tanks during World War II. While the corps has already excavated many of the storage tanks, some still remain, and they still have to test the soil near the area the tanks were buried to measure contamination.
Most of the island’s water comes from Icy Lake at the Pyramid water treatment plant. There were no PFAS detected there.
For now, the city will keep a close eye on the levels, but Tompkins said if those numbers get high enough, they have tools to treat the water.