Newly analyzed monitoring-well data released Friday by the state Department of Health shows levels of petroleum contamination in the groundwater around the Navy’s Red Hill tank farm began increasing in the months following a May 6, 2021, fuel spill, adding to evidence that the Navy did not contain the spill as it has claimed. The contamination levels then spiked higher after another spill in November sent jet fuel into one of the Navy’s drinking water wells and out of the taps of residents, primarily military families, who are served by the Navy’s drinking water system.

DOH says the data also indicates that the contaminant plume has migrated westward in the direction of the Honolulu Board of Water Supply’s Halawa shaft, which until recently supplied 20% of the water for urban Honolulu.

Ernie Lau, manager and chief engineer for BWS, called the findings “concerning and disturbing.”

The data raises new concerns about the threat of groundwater contamination to Oahu’s drinking water system. It also suggests that the environmental impacts of recent spills from the Red Hill facility are more extensive than the Navy has suggested.

The data was presented by Fenix Grange, who manages DOH’s Hazard Evaluation and Emergency Response Office, during a Fuel Tank Advisory Committee meeting that included top Navy officials. The committee was formed by the Legislature in 2014 after 27,000 gallons of fuel leaked from one of Red Hill’s 20 underground tanks.

DOH created heat maps, which show when levels of total petroleum hydrocarbons, a large family of chemical compounds in oil, began to increase in numerous monitoring wells constructed below and in the area around the Navy’s tanks, including the Red Hill shaft.

The maps chart the results of Navy samples that were tested for TPH diesel, which likely indicates a fresh release of jet fuel, and TPH oil, which can suggest the presence of older fuel releases.

The data shows that in the year prior to the May 6, 2021, release, TPH-diesel detections were as high as 2,000 parts per billion at a monitoring well in the middle of the tank farm. In the ensuing months the levels of TPH diesel detected in this well increased to as high as 3,600 ppb from August to October, peaking at 4,100 ppb in February and March before declining. The environmental action level for TPH diesel is 400 ppb. Anything above the EAL could be cause for environmental remediation.

DOH’s maps also show concentrations of TPH oil increasing above environmental action levels following the May 6, 2021, fuel spill, suggesting that fuel from past spills that had seeped into the ground may have been dislodged. Levels of TPH oil in monitoring wells beneath Red Hill tanks had particularly high spikes from August to October. Following the November fuel release, TPH-oil levels spiked in monitoring wells in the tanks underneath and all around Red Hill, with readings as high as 1,400 ppb, more than three times the environmental action level.

Those findings seem to contradict the Navy’s assessments after the November release that the fuel had been funneled into a pipe that had long been forgotten about and exited right by the Red Hill shaft. Based on DOH’s maps, the fuel contamination appears to be much more widespread than that.

“Given that the release happened down at the end of the shaft, this figure is surprising,” Grange said during her presentation.

At the time of the May 6, 2021, spill, the Navy said that about 1,000 gallons of fuel had been released and that its leak detection and response system worked exactly as it was supposed to, containing all but 38 gallons.

When there was another spill on Nov. 20, the Navy said 14,000 gallons of a fuel-and-water mixture had been released from a pipe that is part of the facility’s fire suppression system, but assured the public that there were no signs that it had escaped into the environment and that the water remained safe to drink.

By the end of November, residents on the Navy’s drinking water system began reporting fuel odors from their taps and complaining of symptoms associated with petroleum poisoning, including nausea and vomiting, mouth sores, rashes and burning skin.

In recent months top Navy officials have said that they think as much as 19,000 gallons was released from a pipe in May 2021 and that a portion of that got funneled into a fire suppression pipeline where it sat for months. Then in November, the Navy has said, a worker drove a cart into the pipe, rupturing it and sending fuel spewing into a tunnel, some of which entered a drain line that exited right by the Red Hill shaft.

The Navy ordered a command investigation into the May and November releases on Nov. 29, but those findings have not yet been released.

Capt. Gordie Meyer, commander of Naval Facilities Engineering Command Hawaii, said during Friday’s committee meeting that the report is expected to be released in a matter of weeks.

Meyer didn’t offer up any theories to explain DOH’s maps, but he did take issue with DOH’s finding that the contamination plume had migrated westward, increasing the threat to municipal wells.

“Our initial analysis is that we don’t have enough data to make a determination that the plume is particularly moving westward,” said Meyer. “We don’t have enough to say that it isn’t, but we don’t have enough data to say it is.”

The Honolulu Board of Water Supply shut down its Halawa shaft and two other wells in early December to ensure that the fuel contamination didn’t migrate into its own drinking water system, which supplies most of Oahu. BWS has urged residents to reduce their water consumption by 10% to stave off mandatory water restrictions this summer and the possibility of a mo­ratorium on new development.

In the meantime it’s started developing replacement wells in the event that the Halawa shaft, which was Oahu’s largest well, cannot be restarted. Lau has asked U.S. Sen. Brian Schatz, D-Hawaii, for a $195 million federal earmark to cover the costs.

On Friday he also asked officials with DOH and the U.S. Environmental Protection Agency whether the Navy could be required to cover the costs. DOH Deputy Director for Environmental Health Kathleen Ho said that was a legal question that she would have to get back to him on, as did the EPA.

The Navy agreed to shut down its Red Hill fuel facility earlier this year amid a firestorm of criticism that followed November’s water contamination. While the World War II-era tank farm sits idle, it’s not clear how long it will take to safely drain the tanks, which the Navy says typically hold about 180 million gallons of fuel. The BWS has said it hopes that the fuel will be removed as quickly as possible to remove the risk to the aquifer, which sits just 100 feet below the tanks.

Meyer said he couldn’t provide a timeline but that he didn’t expect it would take “multiple years.”