Over a span of seven decades it's been estimated that more than a million gallons of jet fuel has leaked underground. The mystery is, where did it all go.
A single underground tank as high as the Aloha Tower and four times as wide holds 12 million gallons of fuel.
Twenty of these tanks sit under Red Hill and over time, 19 have leaked.
Those tanks are under close scrutiny these days.
A 2010 risk assessment study for the Navy exposed the risk to the city's Halawa Shaft which supply’s much of Honolulu’s water.
Prior to that date, previous modeling put the direction of contamination moving mauka to makai.
But that pivotal study revealed a new direction—northwest-- in the direction of that critical well.
"The question is now how is the plume moving beyond their property and at which direction and at what concentration," said Board of Water Chief engineer Ernest Lau.
The TEC, Inc report notes:
"The northwest ...groundwater flow may be transporting a petroleum plume...in a direction that is not currently being monitored.”
"That is of grave concern. It is not in our drinking water yet. It hasn’t contaminated that well yet in the last 70 years that the storage tanks have been in use, but we don’t know exactly where it is," said deputy director environmental director gary Gill.
In a letter Lau wrote to the Commander of the navy region Hawaii last month
"The loss of this aquifer has grave consequences to the people of Oahu."
There is also the concern of a potentially catastrophic pill caused by something like an earthquake.
“That kind of catastrophic, disastrous release is what we need to be wary of, and guard against and make sure we have all the safe controls and diversions in place," said Gill.
"We are extremely serious and concerned about this situation and we will continue to advocate for actions by the military and federal government to mitigate this risk. We all pump from the same aquifer, both the military and BWS so it's in our best interest not to contaminate the aquifer.” said Lau.
This week's tour wasn’t the first for state and city officials.
The first time BWS officials admit they were just awe struck at military's engineering marvel, that at one time, was top secret.
This time, they took a more critical look.
Lau tried to put in context: The capacity of those massive fuel tanks far exceeds what Board of Water Supply customers consume in a single day,