The Greater Augusta Utility District has shut down two drinking water wells after testing found levels of PFAS above state limits.
Tests conducted last year of the two wells were below the state limit of 20 parts per trillion, but last month new testing found levels of 23.3 parts per trillion. The wells were immediately shut down, and the district has been using water from its three other wells, said general manager Brian Tarbuck.
"We're extremely, extremely risk averse in the drinking water business for a whole host of reasons.," he said. "So anytime we increase risk, we get twitchy. So this is not a great position for us to be in, but it's the most prudent thing I think we can do."
The EPA has set lower national standards for five PFAS compounds, but public water districts do not have to complete testing or notify the public until 2027.
Under state law, Maine water districts must provide notice of the results and address the contamination now.
Tarbuck said they are in the early stages of evaluating potential filtration systems for the two wells, but will also have to factor in the costs of installing and maintaining filtration.
"And then once we go through the financials and figure out grants, we have to make a decision as to whether or not it makes sense for our rate payers to make that investment," he said. "So do we abandon the wells entirely and just write them off, or do we double down and throw more money at it and put in these filters, which are going to cost a lot to operate."
Tests last year were below the state's limit, but this year they were slightly over. Tarbuck said he suspects the change may be from the state's drought conditions, causing the wells to take in more water from the Kennebec River, which may have had contaminants.
The district has instead been using water from three separate wells, which are further from the river. But using fewer wells for the long term brings its own risks, Tarbuck said.
