A New Jersey landfill has backed out of a plan to take soil contaminated with chemicals from a former naval base in Willow Grove, responding to concerns from activists but leaving unresolved how and when the military will dispose of the tainted soil.

The military had planned by the end of the month to complete excavation — a step toward removing the contamination caused by firefighting foams used at the base that also seeped into public drinking water that serves thousands of Bucks and Montgomery County residents.

But the Cumberland County waste complex that had agreed to accept the soil pulled out of the agreement with the Navy on Monday, amid complaints from activists about depositing the soil in a New Jersey landfill. Like other landfills that deal with contaminated waste, the complex has a containment system meant to keep any chemicals from getting into the environment.

“Rather than get involved in a tit-for-tat … we’ve just decided not to bring the dirt [here],” said Jerry Velazquez, executive director of the Cumberland County Improvement Authority. “We certainly don’t want to be pointed to as the entity that’s creating an environmental hazard.”

The chemicals, known as PFOA and PFOS, ran off the former Willow Grove and Warminster bases and contaminated Bucks and Montgomery County drinking water. Though they have since been cleared from Horsham, Warrington, and Warminster Townships' drinking water, PFAS already appear to have spread into other towns’ water supplies. The chemicals are still moving from soil into groundwater on the Willow Grove base, and a plume of tainted groundwater is spreading, posing a threat to drinking water.

“The potential for continued leaching of PFOA/PFOS to groundwater, used as a drinking water source, presents an imminent threat to the public,” said a Navy report on the planned soil excavation.

The excavation would remove some of the most-contaminated soil from the base. It would also mark action in the slow remediation process at Willow Grove, which includes the monumental task of addressing contaminated groundwater and is largely still in a research, planning, and testing phase.

The Navy did not respond to questions Tuesday about when or where the soil would be deposited. The status of the excavation was not clear.

The question the Navy now appears to face — where will it dump the soil? — underscores the potential difficulty of cleaning up the contamination. While environmentalists have long had concerns about the toxicity of landfills, operators say the containment systems ensure chemicals dumped there won’t contaminate groundwater. Residents and elected officials, meanwhile, have criticized the military for the slow pace of its cleanup process.

PFOA and PFOS are types of perfluoroalkyl substances, also known as PFAS. They have been linked to health problems; elevated levels were found in the blood of some Bucks and Montgomery County residents; and a recent count by the Inquirer and Daily News found that drinking-water supplies in at least 22 other towns in addition to Horsham, Warrington, and Warminster also contained some amount of the chemicals.

New Jersey Sierra Club director Jeff Tittel, one of the environmentalists opposed to the previously scheduled disposal, said the soil should be remediated before being dumped. In the meantime, Tittel said, the Navy should dig it up and store it temporarily at the site so that it is contained and the chemicals don’t continue leaching into the environment.

“It’s good that Cumberland County’s not going to get dumped on by all these toxic chemicals,” Tittel said. “The stuff has to be cleaned up in a more responsible way.”

At least 2,500 cubic yards of soil are marked for excavation on less than an acre, which includes areas of the base near the former fire station and airplane hangar.

“We think it’s a good start,” said Chris Crockett, chief environmental officer for the water company Aqua America. “They’re actually trying to remove the contaminated materials from the area. However, we want that to be done in a safe way that protects all of our neighbors and communities. There’s still a lot more [soil] that’s going to need to be taken off and cleaned up.”

A congressional task force — formed last week and made up of representatives whose communities across the country have dealt with PFAS water contamination — plans to push for Environmental Protection Agency regulations, cleanup funding, and accountability for polluters.

Politico reported Monday that the EPA plans not to set a federal drinking-water standard for PFOA and PFOS or regulate the chemicals under the Safe Drinking Water Act. That means any drinking-water regulation would be up to individual states — or, perhaps, Congress, if a newly formed bipartisan group can succeed in getting legislation passed.

Politico, citing sources within the EPA, also reported that the agency does plan to deem PFOA and PFOS hazardous, meaning polluters could potentially be held accountable for cleanup.

These steps are expected to be contained in a draft plan the EPA has yet to release. If true, they make it likely that the chemicals that have plagued local communities in Bucks, Montgomery, and other counties across the country could become an issue in acting EPA Administrator Andrew Wheeler’s Senate confirmation.

“This is deeply troubling. The EPA exists to protect our air and water, and right now, millions of Americans are drinking water tainted with chemicals linked to cancer, hypertension, and other ailments,” said Rep. Madeleine Dean, a Democrat who this month began representing the contaminated areas of Montgomery County in the U.S. House. “President Trump’s EPA has little interest in environmental regulation, but Congress does. And if the EPA won’t act, we will.”

An EPA spokesperson said Tuesday the report is still under review.

“EPA has not finalized or publicly issued its PFAS management plan, and any information that speculates what is included in the plan is premature,” said Office of Water Assistant Administrator Dave Ross.