LEBANON — The city may have to pay “substantial” costs to bring the Lebanon landfill into compliance with new rules proposed to reduce levels of PFAS chemicals in groundwater and drinking water.

PFAS — or polyfluoroalkyl substances — have been linked to serious health issues, including childhood developmental problems and certain types of cancer. And while levels detected at the Lebanon landfill are within state standards, that’s expected to change soon.

The New Hampshire Department of Environmental Services announced plans on Friday to lower the maximum level of PFOA, a type of PFAS also known as perfluorooctanoic acid, to 12 parts per trillion, down from the current 70 ppt standard. Vermont instituted a limit of 20 ppt last year.

“It’s definitely going to be an issue for the city,” Lebanon City Manager Shaun Mulholland said Friday. “It’s going to be a substantial issue for the city that we’re going to have to address in some fashion.”

The announcement has Lebanon, which has twice detected levels at a landfill testing well above 40 ppt, preparing to take action. Officials hope to set aside money for a treatment project in 2021, although the level of funding is in limbo as the city awaits guidance from state environmental officials.

“It’s not real clear what we’re going to have to do in the future,” Mulholland said, adding that there are several steps regulators could take.

It could cost $190 million to bring landfills, wastewater treatment plants and industrial sites around the state into compliance with the new rules, DES Assistant Commissioner Clark Freise said on Friday. About 80% of New Hampshire landfills have detected some form of PFAS chemicals, he said.

“It may be that all they have to do is a little bit of additional monitoring, so it may be, for some of them, the impact isn’t so great,” Freise said.

The Lebanon City Council was warned Wednesday that state standards likely would force them to take action at the decades-old landfill, which is sandwiched between Route 12A and the Connecticut River in West Lebanon.

Groundwater monitoring wells for the large, unlined portion of the landfill that closed in the 1990s registered PFOA levels of 40.9 ppt in 2017 and 56.7 ppt in 2018, according to the city.

But officials assumed the state standards would hover around 38 ppt, which is what regulators suggested in January. Leachate from lined, newer portions of the landfill that are treated at Lebanon’s wastewater treatment plant test at about 15 ppt for PFOA — three parts per trillion higher than the proposed regulations.

“Obviously, with the announcement today that DES is considering an extremely low rate, one of the lowest in the entire country, the implications are even larger than what we had been anticipating,” City Councilor Karen Liot Hill said Friday.

A single part per trillion is the equivalent of a single drop of food coloring in 18 million gallons of water, or one ounce in 7.5 billion gallons of water, according to engineer Eric Steinhauser, from the Concord-based Sanborn, Head & Associates.

PFAS materials were particularly popular because of their resistance to heat, oil, grease and water, Steinhauser told the City Council on Wednesday. They can be found in many commercial products, such as packaging, clothing, outdoor sporting equipment and nonstick cookware. The substances also work their way into landfills in the form of firefighting foam, industrial waste and sewage sludge.

There are several ways to treat for PFAS chemicals, Steinhauser said, but most methods are either new or still being developed.

And while chemicals were found in groundwater and leaching in low levels into the Connecticut River, they’re not considered a health hazard, Mulholland told the council. Tests of the city’s drinking water system haven’t detected PFOA, he said.

“Right now, there are no drinking water wells that we’re aware of that have contamination in them, so we’re not posing a threat to anybody’s drinking water,” Muholland said.

Concerns about PFAS are relatively new to the Upper Valley, which hasn’t encountered the high levels of contamination found in southern New Hampshire and Vermont. There, the chemicals have dominated headlines and fueled lawsuits and legislation against landfills and manufacturers.

The New Hampshire Attorney General’s Office filed suit in May against eight major manufacturers for damages it argues chemical contamination caused statewide.

Freise, the DES official, said it’s possible that money from the lawsuit could be used to help communities, such as Lebanon, pay for a cleanup, but it’s too soon to tell whether New Hampshire will be successful.

“If the state does get a settlement or an agreement with (the companies) and had a large pot of money, that would obviously be used to help soften the impacts to municipalities,” he said.

More than 700 homes in four Granite State towns have so far been hooked up to new water systems because of contamination, which the state estimates could impact 100,000 people.

Vermont Attorney General TJ Donovan followed suit Wednesday with a lawsuit against 3M and Dupont, claiming the companies are responsible for damage to natural resources and altering groundwater.

PFAS chemicals already were notorious in the Green Mountain State. Three years ago, officials discovered that more than 300 private drinking wells near two former factories in North Bennington, Vt., had PFOA levels above approved health levels.

The discovery resulted in a multimillion-dollar settlement with Saint-Gobain Plastics Performance, the company that purchased the factories, to cover the cost of water line extensions, and efforts to install treatment systems.

Studies suggest that exposure to PFAS chemicals could increase the occurrence of prostate, kidney and testicular cancer, lower the body’s immune system and lower the birth weights of infants, according to the New Hampshire Department of Health and Human Services.

“Some scientists believe that no level (of PFAS) is safe,” said Mindi Messmer, a Seacoast-based environmental scientist who helped identify a cancer cluster in towns surrounding the Coakley Landfill in North Hampton, N.H. (State and federal officials have said there isn’t clear evidence tying PFAS to the cluster.)

Messmer, a former Democratic member of the New Hampshire House, said Lebanon isn’t the only community that would be affected by the new PFAS standards if they are approved by the New Hampshire Joint Legislative Committee on Administrative Rules. Of the roughly 300 landfills in the Granite State, about 292 are unlined, meaning they likely aren’t being treated for the chemicals.

“I actually don’t know of a landfill that doesn’t have PFAS,” Messmer said Thursday. “This is an unfolding situation, and if you don’t have it yet, you’ll probably be hearing about it in the future.”

Tim Camerato can be reached at tcamerato@vnews.com or 603-727-3223.