A well serving Union residents connected to the public drinking water system has been taken offline after tests showed high levels of per- and polyfluoroalkyl substances, often called forever chemicals.
The well operated for a total of 19 days in 2022, and was not used in 2021 or 2020, according to Maine Water Co., which provides water to towns across Maine, including the 100 connections in Union. The well served residents prior to 2020.
Maine Water does not know the source of the PFAS contamination for the groundwater well on Depot Street, which is one of several wells that serve the community in Knox County, spokesperson Dan Meaney said. It is used during peak demand in the summer and was in service between July 22 and Aug. 9 this year.
On Aug. 17, samples collected from the Depot Street well and three other wells that supply the water system showed that only the Depot Street well had detectable levels of PFAS.
At 154 parts per trillion, the results far exceeded the state’s interim standard of 20 parts per trillion for PFAS in drinking water. As of Aug. 9, public water in Union is only coming from sources that had no detectable levels of PFAS, Meaney said.
The contaminated well provided about 21 percent of the water to the system when it was operating this summer.
PFAS are a class of chemicals that have been used for decades in products such as non-stick cookware, waterproof clothing and shoes, and food packaging. There is high confidence that PFAS exposure is associated with increased risk of kidney cancer in adults, decreased infant and fetal growth, and a diminished ability to fight disease and respond to vaccines, according to the National Academies of Sciences, Engineering and Medicine.
There is moderate confidence in associations between PFAS and increased risk of breast cancer, testicular cancer, thyroid disease and other illnesses. The organization recommends that people with a history of “elevated exposure” get their blood tested for PFAS.
In Union, Maine Water found three specific PFAS compounds above the interim standard: PFHpA at 29.3 parts per trillion, PFOS at 43.2 parts per trillion, and PFOA at 64.5 parts per trillion.
The Depot Street well was tested for the first time under a new law that requires all public water systems to test for PFAS by the end of the year.
Only one other public water system serving a municipality has discovered PFAS levels greater than Maine’s standard so far. It was located in Fryeburg, according to a list of PFAS results kept by the state’s drinking water program.
Maine Water is awaiting results from a second round of testing of the Union well from the first week of September. The results will be posted to its website.