Private wells in the vicinity of a farm on Penley Corner Road in Auburn were among those sampled for PFAS contamination by the state. So far, all 21 wells sampled in Auburn have tested below the drinking water standard of 20 parts per trillion. Russ Dillingham/Sun Journal

LEWISTON — Good news for users of private wells in Lewiston and Auburn — water testing has so far shown about 96% of samples with PFAS levels below Maine’s drinking water standard of 20 parts per trillion.

The results come as the state conducts a multiyear campaign to test thousands of sites where sewage sludge or septage was spread, in an effort to remediate any high levels of PFAS contamination.

Earlier this month, the Maine Department of Environmental Protection issued a report to the Legislature stating it had conducted drinking water tests of more than 1,600 private wells last year. Roughly 75% were found to be safe for water consumption, state officials said.

So far, all 21 water samples taken in Auburn, and five of the six samples tested in Lewiston, have tested below the drinking water standard for PFAS.

Per- and poly-fluoroalkyl substances, or PFAS, have been used for decades in a vast array of consumer goods, including nonstick cookware, stain-resistant carpeting and fabrics, waterproof clothing, and grease-resistant food packaging. The substances have been dubbed “forever chemicals” because they don’t break down in the body or the environment.

PFAS contamination in Maine has been linked to the spreading of sludge — the solid byproduct from municipal wastewater treatment — which has been used as an alternative to fertilizer since the 1970s. Since then, the chemicals have been linked to a host of health problems, including cancer, kidney malfunction and immune system suppression.

Legislation passed in 2021 requires the DEP to test anywhere a license was granted to spread sludge or septage, and the department created a tiered system for testing based on factors, including how much of the material was spread on a site. According to the state’s report, the state had finished testing most of the “Tier I” sites by the end of summer 2022, and moved on to “Tier II” sites in the fall. The state expects to begin “Tier III” sites by 2024.

According to Susanne Miller, director of the Bureau of Remediation and Waste Management at the DEP, Auburn has sites that have been prioritized in all four tiers, but only two of 10 sites have been tested so far. In Lewiston, sites have been identified in tiers one, two and four. So far, two of four sites have been tested.

The total of 27 private wells tested so far in Lewiston and Auburn pales in comparison to testing conducted in some other communities. Fairfield, for example, has had 437 samples tested so far, with 167 testing over the standard. Even before the creation of the new state program, testing in Lewiston and Auburn had not shown levels of PFAS coming close to the crisis scenario experienced in the Fairfield region, but some sites have been prioritized as “Tier I.”

Based on state data, the majority of water samples taken in Auburn so far were from residences surrounding farms off Penley Corner Road and Riverside Drive.

Last year, Auburn farmer Roger Gauthier, who hays fields off Penley Corner Road where PFAS testing has been done, said he had lost business due to appearing on a list of sites where sludge had been spread as fertilizer. The state data shows that 16 water samples, all of which are under the standard, were taken from residences near the fields.

In Lewiston, testing was done at residences near a site off Main Street and Merrill Road, and at a closed city landfill off River Road. The single sample testing over the drinking water standard was from a residence near the former landfill, which tested at 94.9 parts per trillion.

Miller said DEP records indicated that 11,730 cubic yards of paper mill sludge from the former Scott Paper Co. in Winslow was used in the topsoil layer of the closed municipal landfill in Lewiston. Because more than 10,000 cubic yards of material was used there, it was designated a tier one site. The Fairfield crisis has been linked to waste from nearby paper mills, which have used the compounds when making coated paper products.

The results so far, however, are considered preliminary. Miller said that’s because the state is still researching and reviewing files related to the licensing of sludge applications that date back years. She said follow-up sampling may still be necessary at some of the sites where the DEP has initiated sampling.