The Navy may soon have to install a sophisticated leak detection system at it’s massive Red Hill Underground Fuel Storage Facility where thousands of gallons of fuel leaked last month.

The state Department of Health urged the Navy to put in a better leak detection system as far back as 2008, but the Navy has resisted despite evidence that fuel has been contaminating the groundwater and the pollution may be moving toward a nearby Navy well that supplies drinking water to about 65,000 people at Joint Base Pearl Harbor-Hickam.

The Honolulu Board of Water Supply says it also is concerned that decades of contamination could close in on important drinking water supplies, and wants to be much more in front of any potential threats. Local officials are already stepping up testing at a cost of tens of thousands of dollars after last month’s 27,000-gallon spill.

And now the U.S. Environmental Protection Agency is moving to tighten a law — as early as the end of the year — that has allowed the Red Hill facility and other “field constructed tanks” to escape leak detection and prevention regulations. About half a million underground storage tanks throughout the country have been subject to the regulations for three decades.

“Field constructed tanks are extremely rare,” said Steven Linder, a program manager for the EPA’s underground storage tank program. “But when something does go wrong, they are so big that it is a big problem.”

Dozens of leaks from Red Hill’s 20 underground fuel storage tanks over the past 70 years have contaminated groundwater with hydrocarbon levels as high as 25 times what the state considers safe, records show.

Test results for nearby drinking water wells have so far come up clean for contamination, but monitoring is ongoing.

A History of Leaks

Civil Beat reviewed hundreds of pages of records related to the Red Hill facility, including groundwater contamination reports, Navy risk assessments and correspondence between Navy and state health department officials. The documents were provided by the Hawaii Department of Health through a public records request.

The documents show that leaks from the facility began as early as the late 1940s, just a few years after the World War II-era facility was built, and continued for decades. Meanwhile, groundwater near the facility has repeatedly tested positive for high levels of hydrocarbons since regular monitoring began in 2005.

The 144-acre Red Hill Underground Fuel Storage Facility is less than three miles northeast of Pearl Harbor in Halawa Heights.

Military personnel, as well as local and mainland laborers, buried 20 giant tanks, each the size of a 20-story building and capable of holding 12.5 million gallons of fuel. Encased in concrete, the tanks are laid out in two rows and connected to Pearl Harbor through a system of pipes, as well as an underground rail system. For decades the tanks have supplied jet and marine fuel to the military’s Pacific operations.

The tanks are surrounded by a number of drinking water wells, the closest being a Pearl Harbor well that is 3,000 feet to the west. Contamination below the facility appears to be moving slowly and has shown up in a monitoring well downhill from the tanks.

In 1995, the American Society of Engineers deemed the Red Hill facility a historic landmark, a category it shares with the Hoover Dam, Panama Canal and Statute of Liberty.

But while Red Hill is considered an engineering marvel, documents show that it also has a long history of leaks.

Historic records compiled by the Navy in a 2008 groundwater protection plan indicate that there were more than 30 leaks over the course of six decades at the facility, spilling tens of thousands of gallons of fuel.

The records, including inspection reports and written histories, are spotty, however. Many of the reports of leaks contain no information about how much was spilled or when the leak was finally fixed and in some cases the leaks may have been internal to the tank.

But the records suggest that at least 170,000 gallons of fuel was spilled over the years, or the equivalent of all the fuel on site at six modern-day gas stations.

For many tanks, the history of spills ends in the early 1980s and it’s unknown exactly how many leaks there may have been in the decades since then.

But the records show that there were likely two spills in the 1990s. And in 2002, the Navy submitted a fuel release report to the state health department indicating that there had been a spill of jet fuel at Tank 6 and that the tank had been drained and taken out of service. Navy spokesman Tom Clements said it was not clear if the report was in response to a leak that year or detection of an old spill.

A 2008 groundwater protection report prepared by the Navy says that “based on various types of leak tests conducted since 1997, other releases may have occurred.”

The Navy has been aware of the risks that groundwater contamination poses to drinking water supplies for at least 15 years.

A 1998 analysis conducted by Willbros Engineers warned of the dangers involved in a worst-case scenario if large amounts of fuel were to leak.

“An uncontrolled massive fuel release from the Red Hill tanks . . . would cause irreparable damage to the drinking water source below the site,” according to the report. “The cost of clean up would be prohibitive, long term, and may not be completely successful.”

As the facility ages, risks associated with leaks are expected to increase.

The “aging of the facility will increase the possibility that such a release could occur as a result of leaks breaching both steel liners and concrete containment of the tanks,” according to a 2009 Navy work plan. “While the tank steel liners have been repaired, the concrete containment cannot be maintained.”

Chemicals from Fuel Pollute Groundwater

State health officials, who are responsible for regulating the facility, say they first became aware of the leaks in 1998 when the Navy began testing the bedrock beneath the tanks for fuel contamination.

By 2002, the tests showed that all of the Navy’s tanks had been leaking, except for one, according to Steven Chang, head of the state health department’s solid and hazardous waste branch.

Monitoring wells can show significant drops in fuel levels, but it’s possible that tanks can also have chronic low-level releases that are not being detected, he said.

Under pressure from the health department, the Navy began conducting extensive tests of the groundwater and its drinking water well, documents show.

In 2004, Chang threatened to start fining the Navy $500 for every day it failed to submit reports related to fuel contamination, according to written communications with the Navy.

By 2013, the Navy had drilled seven monitoring wells that start near the northern tip of its tanks and follow the projected flow of water toward the Pearl Harbor drinking water well. The monitoring wells help track whether chemicals contained in fuel are migrating at dangerous levels toward the military base’s water supply.

A review of the past six years of records shows that the levels of hydrocarbons in the monitoring wells often exceed state standards, but the levels vary. The tests, conducted several times a year, show that hydrocarbon levels rise and fall at various wells.

The levels that are of most concern are in the monitoring well that is just 600 feet away from the Pearl Harbor drinking water well.

That well “is of greatest concern because its (hydrocarbon) results have been consistently greater than HDOH environmental action levels,” according to a 2010 risk assessment.

As of September, the last available report from the health department, two of the six wells tested above the state’s acceptable level for hydrocarbons. Two months earlier, three of the monitoring wells exceeded state standards.

Navy and state health officials say that there have never been any tests that show that the Pearl Harbor drinking water supply has been contaminated with unsafe levels of chemicals associated with fuel.

Still, in recent years low levels of hydrocarbons and lead have shown up sporadically in the Navy’s drinking water well.

“It appears and it disappears and reappears,” said Chang. “It is very dilute and we really are not sure what is happening to any petroleum that was released” in the past decades.

Stuart Yamada, of the health department’s safe drinking water branch, said that it is hard to track the movement of fuel through the ground, but that modeling suggests it moves slowly. And while tests show that there is “an awful high presence” of hydrocarbons in the groundwater, he said that it doesn’t appear to be moving at high concentrations toward the Navy’s drinking water well.

Still, a 2009 Navy analysis warned that a release of just 16,000 gallons of fuel from some of the tanks could potentially send benzene, a known carcinogen, into the well that supplies water to homes and offices on the military base.

County Wells a Mounting Concern

While the Pearl Harbor well is of greatest risk for contamination, county water officials worry that the fuel also threatens a critical drinking water supply for Oahu.

The Red Hill facility sits just 100 feet above the water table, straddling the Waimalu and Moanalua aquifer systems. The closest county drinking water well is about 5,000 feet to the northwest of the facility and supplies approximately 12 percent of the water to a system serving more than 600,000 Oahu residents. Another three county wells are about 6,700 feet to the south.

Even though Navy and state health officials have known about the groundwater contamination since the late 1990s — and generated thousands of pages of reports on the topic — officials from Honolulu’s Board of Water Supply say they were never informed about the problems until after this most recent spill. The BWS is responsible for the county’s drinking water.

“I’m very concerned abut the situation,” said Ernest Lau, manager and chief engineer for the BWS. He stressed that the nearby aquifers are critical to Oahu’s drinking water supply.

Lau said he hoped to get help from the Navy in coming up with some sort of modeling to tell if a fuel plume was moving toward the county’s wells and wanted to talk with the Navy about trying to remove the fuel contamination to reduce the risks.

However, Clements, the Navy spokesman, said that cleaning the groundwater is “impractical and cost prohibitive” because of the unknown nature of the basalt underneath the facility.

There are no requirements that the Navy clean up past groundwater contamination, according to the EPA, unless the military closes the facility. Only spills that were reported to the state health department, such as the most recent one, require the Navy to take any action.

The water board temporarily shut down nearby wells after last month’s spill and is increasing tests for fuel contaminants from once every three years to four times a year for the next two years at a cost of $52,000.

But if officials had known earlier about the decades of leaks and contamination, increased surveillance would have begun a lot sooner, said Erwin Kawata, quality control administrator for the Board of Water Supply.

Yamada called the health department’s failure to notify the Board of Water Supply an “oversight.”

“Normally we like to keep them informed,” he said.

But he stressed that the current risk to the county water supply was likely minimal.

Studies conducted by the Navy in 2007 and 2010 indicate that the contaminated groundwater wouldn’t migrate into county wells because they are situated at a higher groundwater elevation.

However, if the Navy’s Pearl Harbor drinking water well were to be shut down for any reason, things could change, said Yamada.

The Navy well acts like a “vacuum,” he said, sucking water down hill from the facility. Without it, there would be an increased risk that the contamination would flow into the county drinking water wells, he said.

New Oversight Could Prove Costly for Red Hill

Although the 27,000-gallon spill was announced by the Navy in mid-January, Chang of the state DOH said there’s evidence that the leak could have begun as early as the end of December. Navy and government officials are still trying to determine where the leak occurred and whether it escaped the facility or contaminated groundwater.

Health officials have urged the Navy in the past to implement a “viable leak detection method,” and the Navy responded by making this a key component of its 2008 work plan.

Navy spokesman Clements said that the Navy did implement a system in 2009 that includes performing “tank integrity tests” every two years. This is in addition to routinely checking the fuel levels in its tanks and sampling groundwater and soil vapor, he said.

“We continue to improve our system of monitoring and detection and incorporate new technologies whenever possible,” Clements said by email.

But state health department officials don’t believe the Navy’s leak detection system has improved or is effective.

Chang noted that the recent leak was only discovered based on readings of fuel levels in its tank and increases in vapor levels below the facility.

“If they had anything else they would have shared that with us,” he said.

Clements said that the Navy’s system of checking fuel levels is the best way to tell if there is a leak.

But regulations for the Red Hill facility are expected to get a lot stricter.

In the 1980s, media reports about the health and environmental dangers posed by leaking underground fuel storage tanks prompted a series of federal laws that increased regulatory oversight of the tanks.

However, those regulations were focused primarily on gas stations.

Red Hill and about 40 other military facilities throughout the country were exempted from leak prevention and detection requirements, according to Linder of the EPA.

The EPA is currently in the process of proposing new rules for the military tanks that could take effect as early as the end of this year.

That could mean that the Navy will have to invest in costly new technology, including double lining its tanks and installing sophisticated sensory systems that can better detect leaks and where they are happening.

“The main thing is how could we move forward to identify where the release is and what can we do to capture it before it moves any further,” said Chang.

The costs for the Navy to comply with new rules could be substantial.

“The Navy will really have to take a hard look and say, is it even reasonable for them to spend the kind of money necessary to provide all the proper release detection systems,” said Chang, noting that some tanks might end up being shut down.

“It may come down to well, they don’t have enough money to upgrade all 20 tanks, maybe they will only be able to upgrade five.”

Clements said that it was too speculative to comment on what technologies the Navy may have to implement in the future or whether added costs could hamper Red Hill’s operations.