Constructed amid rising World War II tensions, the Red Hill Bulk Fuel Storage Facility’s 20 steel-lined tanks — each large enough to swallow a 20-story building — are buried under 100 feet of volcanic rock. The American Society of Civil Engineers lists the site among some 200 projects worldwide designated as an engineering landmark, representing “achievement of what was considered an impossible dream.”

But even masterfully made things have a shelf life. Nearly eight decades after the Navy’s Red Hill dream was realized, it’s apparent that operation of the facility — which can store a total of 250 million gallons of jet fuel, fuel oil, gasoline and diesel fuel to support military operations — is not fail-proof. That alone should be alarming to Hawaii residents as this wartime project near Pearl Harbor sits a mere 100 feet above Oahu’s primary drinking-water aquifer.

The latest incident prompting justifiable concern among environmentalists and others is a leak of about 1,000 gallons of jet fuel during a fuel transfer. While the Navy has maintained that all of the fuel was “captured and fully contained,” new data released by state Department of Health (DOH) shows that in the days after the May 6 leak, soil vapor levels indicating petroleum contamination spiked well above averages.

While the cause of the leak is still under investigation, there are related unsettling questions such as: Why did 13 hours pass before the Navy notified DOH, which serves as a site regulator along with the U.S. Environmental Protection Agency? And why are there glaring gaps in data that the Navy collected and provided to regulators? Daily soil vapor readings for three tanks near the leak are not listed in the week following the incident.

During a briefing last week before a committee created by the Legislature to monitor the tanks, the commander of Naval Facilities Engineering Command Hawaii said in the Navy’s assessment that the leak had “no environmental impact or impact to the groundwater” — but provided few details about what happened, citing the ongoing investigation. This tight-lipped update fell short of the transparency level the public deserves.

Also, such murkiness erodes public trust, which has frayed in some circles since 2014, when the Navy reported a 27,000-gallon jet fuel leak at one tank and later said it was caused by a contractor’s poorly performed work and the military’s own insufficient oversight. Seven years later, the Navy is still haggling with regulators over what constitutes a suitable long-term solution for safely maintaining a massive supply of petro for ships and jets.

The Navy has said, in the long run, it wants to either upgrade its single-walled tanks to a “double-wall equivalency secondary containment,” or relocate the fuel. It’s somewhat encouraging that while the price tag for double-wall technology appears to be too steep to be “fiscally-responsible,” in the Navy’s view, the military branch has stated commitment to “finding a solution for secondary containment.”

But outweighing any encouragement is exasperation in regard to foot-dragging. There’s no set timeline for installing a double-wall fix. As for the other proposal, the Navy wants to set a 2045 deadline for removing all fuel from the tanks, which will then be 100 years old. Underscoring the risk tied to such delay is a report that pegged the probability of a sudden leak of between 1,000 and 30,000 gallons this year at 27.6% — and rising to 96% over the next 10 years.

With the threat of petro-tainted groundwater ever- looming, the Navy owes Hawaii much greater candor and accelerated action in shoring up viable short-term and long-term solutions that address the aging facility’s limitations. All that is vital, to protect our priceless and irreplaceable aquifer and pure drinking water.