The one fact seemingly not in dispute is that one or more pits, apparently used for chemical disposal training or manufacturing, lie beneath the pavement at the southwest corner of the airport, near where railroad tracks cross Vineland Avenue.
Airport spokesman Victor Gill said no manufacturing has taken place there since the airport bought the land from Lockheed in 1978.
Shortly after the airport took over, Gill said, it leased the land to a firm called Flight East.
"They promptly paved it over and used it for parking small, privately owned aircraft," Gill said. "That paved-over condition is what exists today."
The land was unimproved before World War II, when the Air Force acquired it and used it for barracks, as well as medical and other training, he added.
"They did nothing remotely similar to manufacturing or any use that can [contaminate] groundwater tables," Gill said. "The only blank spot to work with is that period from 1963 forward, when the property was under Lockheed authority," Gill said.
Lockheed has argued that the soil was polluted during the years of government use.
Lockheed spokeswoman Gail Rymer said in an e-mail that the site was used by the Civil Air Patrol and the Air National Guard, and two pits there "appear to be a source of a significant solvent plume."
But, she asserted, Lockheed did not operate the pits or dispose of chemicals there.
"There is no evidence that the release occurred during our ownership," Rymer said. "Even more importantly, there is no connection between our manufacturing and the fire pits."
Michael Massey, assistant regional counsel for the EPA, said the agency is aware of the dispute, but is not ready to blame the military.
"We are looking into site history to see if we can figure out all the relevant facts that relate to operations there," he said. "But we don't have any additional parties that we can conclusively identify who would have liability for that part of the airport."
Massey said that the EPA investigation will continue, and that if it can ever prove what happened, both the airport and Lockheed might have an out.
"If you purchase a piece of property that was already contaminated, and all that contamination was the result of activities of a third party, and at the time of your acquisition you did not know and had no reason to know there would be contamination, you have a defense to liability," Massey said.