Federal, state and local elected officials, and environmentalists, have feared that the U.S. Department of Defense would try to escape responsibility for the contamination that has closed the City of Newburgh’s main drinking water supply for nearly a year and frightened residents.

A document obtained by the Times Herald-Record gives weight to those fears.

It shows that the military believes that its lease agreement for the state-owned land used by Stewart Air National Guard Base exempts it from having to clean the contamination being blamed on the use of firefighting foams at the base.

Language in the 1982 agreement with the state Department of Transportation, which owns the property, holds the federal government harmless for “any restoration of the premises” and prohibits claims for damages “arising out of the Government’s use,” according to the document.

The military also cites the licensing agreement between the U.S. Air Force and the state for use by the New York National Guard. That agreement requires that costs for “restoration” be paid by “funds available to the licensee,” in this case the state.

“It is unacceptable that the U.S. Department of Defense is attempting to evade responsibility for the contamination they have caused,” Basil Seggos, commissioner of the state Department of Environmental Conservation, said Thursday. “The New York State Department of Environmental Conservation will continue to hold DoD accountable and take aggressive action to protect the health and safety of the community.”

If the agreements’ language becomes the military’s official defense, it sets up a battle with the state over who will pay for cleaning the contamination at Stewart Air Base.

It may also threaten the state’s planned efforts to recoup what it has spent in response to Newburgh’s contamination – a tab that easily could top $30 million.

Those costs include a new filtration plant for the city whose final cost is expected to exceed $25 million and reimbursements to New York City, which has been selling Newburgh the water it currently uses.

“This is very disturbing, and we’re looking into it,” said Jason Kaplan, a spokesman for Sen. Charles Schumer, who has been among the elected officials pushing DoD to take ownership of contamination at the base.

Officials at the DoD could not be reached for comment.

Last August, the state DEC designated Stewart Air Base a Superfund site after a months-long probe into the levels of perfluorooctane sulfonate in Newburgh’s Washington Lake, which has long supplied drinking water for city residents and businesses.

Investigators believe the chemical, also known as PFOS, has been carried into the lake’s watershed after being discharged from a retention pond at the air base that collects stormwater. The pond discharges into Silver Stream, whose waters Newburgh diverted to Washington Lake.

Two accidental discharges from hangar-based fire-suppression systems spewed a combined 4,000 gallons of foam in 1990, according to the DEC.

One of the samples taken at the retention pond showed 5,900 parts per trillion of PFOS, about 84 times the level at which the Environmental Protection Agency recommends action.

Elevated levels of PFOS have also been found in residents from the City of Newburgh and the surrounding towns who have had their blood tested as part of program launched by the state Department of Health in response to the contamination.

Initial results for city-only residents showed average levels nearly four times the national average for PFOS, which has been associated with kidney and testicular cancers, high cholesterol, low infant birth weight and other health problems.

More results are being mailed out this week.

“We still believe the Department of Defense needs to take responsibility for contaminating the drinking water supply for nearly 30,000 people, and several tributaries of the Hudson River,” said Dan Shapley, director of Riverkeeper’s water quality program.

lsparks@th-record.com