Multiple fuel leaks over the decades have occurred in giant Navy tank facilities that are underground. Much more information about this system belongs up here at the surface of the civilian world, where the broader environmental impacts of the leaks must be discussed more openly.

The problem centers on the Red Hill Bulk Fuel Storage Facility near Pearl Harbor, and near a freshwater well that is used as a Pearl Harbor drinking water supply. The most recent spillage, reportedly up to 27,000 gallons of JP-8 aviation fuel, was announced in January, but this World War II-era facility has a long record.

It all came to light in a 2008 report that environmental activist Carroll Cox obtained from the state Department of Health and then relayed to the Star-Advertiser.

In the document, the Navy lays out a groundwater protection plan it developed at the Health Department’s request after previous investigations of the facility showed leaks had contaminated the soil and basalt rock beneath it, as well as a Navy groundwater cache.

The risk to public wells serving the Oahu community at large is unclear; there are underground barriers that tend to protect the nearest public source, the Honolulu Board of Water Supply Halawa shaft, about a mile away. The well most at risk serves an estimated 52,200 people who live and work at Pearl Harbor. However, the aquifer system is not impermeable, so contamination in one area has to be a matter of general concern.

The Red Hill facility had been classified so independent investigations of spills were not done before 1995. Chemicals in the water tend to persist for a long time, so more timely and more publicly available information on the facility is essential. Cox is right to suggest that a legislative hearing be scheduled to bring more of the information out front and center.

The Navy’s report cites dozens of fuel leaks going back to 1949. Among the scattered citations is the startling note that between 1970 to 1972 there was an "unexplained" fuel drop of 31,294 gallons. In some cases, the report states, the leaks went into internal tank piping; sometimes the spill was contained within the concrete casing of the tanks. But for some incidents the report gave no indication of where the fuel went.

The area surrounding the tank involved in the Jan. 18 incident is now being vented, and workers won’t be able to investigate the source of the leak until that’s done after several weeks, officials said.

But what’s already known is disturbing enough. Steven Chang, who heads the Health Department’s Solid and Hazardous Waste Branch, said the Navy had just brought the tank back into service in December, and when it was filled up it started to leak, eventually losing up to 27,000 gallons.

How that could happen given the stated upkeep procedure is unexplained. Navy officials assert that the tanks undergo a preventive maintenance cycle, involving inspections and repairs to restore a tank to "like new" condition. The fuel levels are tracked daily, they said, and any discrepancies are investigated.

It would seem that a system activated in 1943 would have been overhauled by now, or at least better understood.

Health officials said very low levels of lead have been detected in the Pearl Harbor water system, and noted similarly low levels of hydrocarbons in past records; both are below state action levels.

Regardless, it wouldn’t take much to do real damage to the water supply. A release as small as 16,000 gallons near Tanks 1 or 2, those closest to the water tunnel, could result in excessive contamination, according to the report.

Public authorities, civilian as well as military, have to get a better handle on this. The fuel storage facility is "critical" to the Navy’s mission, officials said. The same could be said about a safe drinking water supply.