A federal agency’s decision to prioritize chemical cleanup of wells where contamination is three times below new federal limits has prompted calls for faster action and money for public water at the former Grumman plant in Calverton.

At a public forum Oct. 29, Navy officials told members of an advisory board overseeing the Navy’s remediation at the Grumman site that it would adhere to a 12 parts per trillion standard for poly- and perfluoroalkyl substances, or PFAS, in drinking water – three times the EPA limit set by the Department of Defense.

The Environmental Protection Agency determined in April stricter standards requiring utilities to limit “forever chemicals” in drinking water linked to cancer, developmental harm and other health problems. Man-made chemicals are commonly found in firefighting foams and do not break down naturally. The 4 parts per trillion limit exceeds current state standards for contaminants in Long Island’s drinking water.

The Defense Department said its parameter “prioritizes action where PFAS levels are highest, rather than delaying action at these locations while remedial investigations continue,” according to a September note. But frustrated residents say the move will only delay cleanup efforts and have asked the Navy for $2 million to pay for public water extensions to homes near the facility.

The Navy is responsible for cleaning up the former Naval Weapons Industrial Reserve Plant in Calverton, where Grumman once tested fighter jets.

Navy testing in 2016 showed PFAS in groundwater at the site. Private drinking fountains east on River Road also detected PFAS in 2018 and 2019, officials said.

Naval engineer Addison Phoenix said an analysis of data from private wells on River Road shows “no exceedance” of Defense Department guidance.

Frank Mancini, superintendent of the Riverhead Water District, said that’s misleading.

“You have detections above (4 ppt) in private wells right now on River Road that you know are causing the plume,” he said at the meeting. “You present it as, ‘It didn’t reach our action level.’ But you just upped the ante.”

Navy spokesman David Todd said the highest result detected was 11.2 parts per trillion. That well was retested in 2019 with a result of 2.15 parts per trillion, he said.

While the Navy acknowledged the plume is moving south and southeast toward the Peconic River, Todd said, “It is unknown at this time if the plume is migrating east toward River Road.”

Last year, state health officials warned against consumption of fish caught in the Peconic River due to PFAS contamination.

At the meeting, Mancini and other city officials asked the Navy for $2 million to connect 28 homes on River Road to public water while their investigation continues. Riverhead Town has grants to cover most of it $6.9 million project and said the funding would bridge a gap.

In 2024, the Navy has budgeted about $1.9 million for the site, Todd said.

Phoenix said the latest Defense Department policy does not allow them to take action.

“We’re still figuring this issue out,” she said of the contamination. “It’s just a little more elaborate process here because of how many sources of contamination we have.”

The Navy complies with the federal Comprehensive Environmental Response, Compensation and Liability Act, or Superfund program, an arcane process that involves extensive investigations and studies before remediation can begin.

“In the meantime, the water is still contaminated,” said Dawn Thomas, who leads community development in Riverhead. “So put the pipe in… and then you can take what you want because we know people won’t suffer.”

Navy officials said testing will continue this fall and updates will be given at the next advisory meeting in January.