The Navy has reported a second case of petroleum contamination in a drinking water source at its Joint Base Pearl Harbor-Hickam site in Hawaii, raising concerns from health officials.
In a statement on Wednesday, the Hawaii Department of Health said the Navy had identified diesel fuel levels more than double the department's limits for drinking water at the Aiea Halawa Shaft.
The shaft is one of three ground water sources providing drinking water to the Joint Base Pearl Harbor-Hickam water system, which includes water distributed to military families.
“The level of this contaminant poses a public health threat, and is considered unsafe to drink,” Kathleen Ho, deputy director for environmental health, said in a statement.
Ho said the development was "concerning — especially as the cause of the petroleum release into the Navy’s water system remains unknown."
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"We will continue to take all possible action to protect public health and the environment," she said.
It comes after a petroleum contamination was discovered in another drinking water source affecting military families at the same base.
On Wednesday, the Navy said it said it would stop operations at fuel storage tanks above a Hawaii aquifer until it had completed an investigation into how petroleum got into the drinking water.
“The safety, health and well-being of our service members, civilians, contractors, their families and our communities here in Oahu is of the utmost importance to me,” Navy Secretary Carlos Del Toro said in a statement.
“This is not acceptable and the Department of the Navy will take every action to identify and remedy this issue. We will continue to coordinate with federal, state and local entities to restore safe drinking water to the community," Del Toro said.
Still, the Navy also informed Hawaii officials it was contesting a state order demanding that the suspension remain in effect until independent evaluators can ensure that appropriate actions are taken to protect drinking water.
The health department said the Navy reported that it drew the new sample of contaminated water at the Aiea Halawa Shaft on Dec. 5. However, the Navy said the shaft had been offline since Dec. 3.
The contaminated water, the health department said, had a level of 920 parts per billion of total petroleum (ppb) hydrocarbons diesel range organics — more than double the 400 ppb considered to be at the "Environmental Action Level, or the level at below which "no human health effects are expected."
The department is expected to collect further samples from the Aiea Halawa Shaft Thursday.
