WASHINGTON -- Federal scientists studying the history of water contamination at Camp Lejeune have learned of another source of spilled fuel that occurred years ago - this one less than a football field away from a drinking well that once served thousands of Marines and their families.
That well was closed in December 1984 after benzene was found in the water.
The source of contamination that scientists now are exploring was once an on-base refueling station within an area of the Marine base known as Hadnot Point. The refueling facility, known as Building 1115, contained seven underground storage tanks that ranged in size from 1,000 to 5,000 gallons.
The extent of the historic contamination across the Marine base - and its sources - are important details for federal scientists at the Agency for Toxic Substances and Disease Registry, an arm of the Centers for Disease Control in Atlanta.
Officials at the agency were unable to respond Thursday to e-mailed questions about Building 1115. A spokeswoman said key resources were unavailable.
Scientists are working on extensive water modeling research to understand the health impacts of the various contaminants. Those include trichloroethylene (TCE), tetrachloroethylene (PCE), benzene and vinyl chloride. Benzene is a key component of gasoline and a known carcinogen.
It's estimated that up to a million people were exposed to the contaminated water at Lejeune from the mid-1950s to the mid-1980s.
A review of hundreds of documents about the extent of benzene and other chemical contamination at Camp Lejeune also found that benzene remains in untreated groundwater at levels thousands of times higher than the federal drinking water standard, and benzene has seeped into the deep aquifer far below the base.
Nearly three decades after contaminated wells were closed, monitoring wells are finding poisons at thousands of times the drinking water safety standards in the aquifers below the military base, according to state documents. Monitoring wells have been installed around the base to help officials understand what contaminants remain in the groundwater.
As recently as January, benzene was tested at 18,600 parts per billion from one untreated groundwater monitoring well at Lejeune. The federal standard for drinking water from the Environmental Protection Agency is 5 parts per billion; the state of North Carolina pegs it at 1 part per billion.
Benzene is a known human carcinogen.
There is no evidence that contamination exists today in Lejeune's drinking water. But the plumes still lurking in the aquifers underground are testimony that the contaminants at the base were extensive - and that much of them remains.
The Marine Corps and the Department of the Navy are undergoing an extensive, multimillion-dollar cleanup program under the oversight of the federal Environmental Protection Agency and the state Department of Environment and Natural Resources.
1 million gallons
A 1993 review of environmental treatment options shows storage tanks containing fuel, cleaning solvents and other chemicals were buried at sites across Camp Lejeune over the years.
Many of the storage tanks leaked. Just how badly is unknown. But officials have estimated that more than 1 million gallons of fuel may have seeped into the sandy soil at the base, according to memos.
A monitoring report in 1988 described a 15-foot layer of fuel floating on top of the water table, just a few feet below the surface of a fuel farm at the Hadnot Point Industrial Area. The same report showed evidence of benzene in monitoring wells at levels of up to 29,000 parts per billion.
Other documents show that in 2006, benzene at levels of more than 7,000 parts per billion was being found far below the land surface, in what is known as the deep aquifer.
Fuel floats atop water and normally wouldn't be found so far below ground.
A contractor told the military in 2008 that historic amounts of over-pumping by the base's wells appeared to have sucked fuel and other contaminants down into the deep aquifer. The contaminants then became trapped, where many of them still remain.
Low level still toxic
The transcript of a 1988 technical review committee meeting of federal, state and military officials illustrates the scientists' concern about benzene as they discussed the Hadnot Point fuel farm.
In the meeting transcript, one official mentions a water-monitoring test showing benzene in the aquifer at 30 parts per billion. He describes the test result this way: "Fairly low, but still toxic enough that you don't want to touch that water."
Over the years, investigators discovered what appeared to be new spills after the problematic water supply wells were closed. For example, several reports in the early 1990s showed that another underground storage tank, at Building 1613 in the Hadnot Point Industrial Area, appeared to have no fuel leaks.
But in 1996, a consultant's report showed that TCE and a petroleum plume were found during an investigation at Building 1613.
Scientists studying the fuel contamination have known about and been looking closely at the impacts of more than a dozen underground storage tanks at the Hadnot Point fuel farm. The tanks were about 1,200 feet from a drinking well known as Hadnot Point 602.
That water supply well was closed in December 1984 after a Navy contractor found high levels of benzene in it. Its closure prompted a review of other wells across the base, several of which also were shut down.
Scientists then learned about Building 1115, with its seven underground tanks. That site is about 300 feet from Hadnot Point Well 602.
"You could literally stand at this site and throw a golf ball and hit Well 602," said Jerry Ensminger, a Marine veteran and former Lejeune resident whose daughter, Janey, died in 1985 of childhood leukemia, which he believes was caused by the contaminated water.
"God, each time they switched on Well 602, it was, 'Eureka! Benzene for everybody,' " said Ensminger, who has testified before Congress about the contamination.
Tanks buried 50 years
The reports on Building 1115 are part of a series of documents scientists have combed through in the past year about contamination throughout the Hadnot Point Industrial Area. Many of the documents were part of contractors' reports and memos, written during the 1990s and 2000s, between the military and the state of North Carolina.
The tanks at Building 1115 were installed as early as 1943, just as Camp Lejeune was taking shape, and were dug up 50 years later in 1993, documents show.
A site contractor removing the tanks warned the Marines that the tanks showed signs of leakage, that contaminated soil had been removed, and that there were "signs of contamination over the entire site."
The contractor recommended turning the site over to a federal environmental agency.
Later, government officials indicated that the two plumes from Building 1115 and the Hadnot Point fuel farm - some reports show three plumes - had mixed.
Documents in 2000 showed that years after the fuel tanks were removed from the Building 1115 site and the Hadnot Point fuel farm, 4,000 feet of piping remained underground, and that it appeared to have connected the two sites.
