After many months of testing the Pearl Harbor water system, Navy officials said on Thursday they are still unable to explain what is causing residents to see sheens on their water and experience new and ongoing health problems. 

Detections of total petroleum hydrocarbons, or TPH, found in test samples throughout the last two years don’t necessarily indicate the presence of petroleum, according to a Navy presentation at the Red Hill Fuel Tank Advisory Committee. 

Low levels of TPH could be caused by a number of unrelated factors, according to Chris Waldron, an environmental engineer with the Navy and Marine Corps Force Health Protection Command. Non-petroleum substances like fatty acids or phthalates – chemicals found in plastic – could trigger a positive test for TPH, he said. Those substances could be introduced in the lab itself, he said.

“In a sense you could call them false positives,” Waldron said at the public meeting. 

The Navy says it has tested more than 8,000 samples in the last two years since fuel from the Navy’s Red Hill fuel storage complex leaked into the water system. In that time, community members have consistently expressed concerns about the possibility of residual fuel in the system.

But none of the samples have exceeded a threshold set by the Hawaii Department of Health that would trigger further action: 266 parts per billion of TPH. The samples also don’t follow scientific patterns that would match the kind of jet fuel that was stored at Red Hill, Waldron said.

Meanwhile, Pearl Harbor water users continue to report health challenges they believe to be connected to drinking and using the water. They have also questioned whether the state’s testing threshold is too high. DOH has stated it intends to establish a new standard. 

The U.S. Environmental Protection Agency in December raised concerns about the low but persistent levels of TPH in the Navy’s test results. The regulator urged the Navy to investigate the root cause.

On Thursday, Waldron said the Navy has been investigating with help from regulators and outside experts. The group ultimately determined that the most likely explanation for the ongoing TPH detections are “laboratory method challenges,” the Navy presentation said.

Most of the TPH detections fall between 50 and 80 parts per billion. That is below the level at which lab personnel have a high degree of confidence they can accurately identify what they’re seeing, Waldron said. He compared it to zooming in a camera so far in that the image becomes blurry.

“We’re pushing the method to its limits,” Waldron said. “With that, we’ve got to do a little bit more homework rather than just looking at a number.”

To that end, Navy teams are investigating the hot water heater of a household with one of the highest TPH detections. Residents have suspected for many months that fuel may have contaminated their homes’ heaters and could be leaching petroleum continuously into their water. Navy Capt James Sullivan said those samples are being processed.

But Waldron all but ruled that possibility out. Contamination would have dissolved in the water, and flowed with it, he said.

Making matters murkier is that the TPH detections don’t follow a trend on a map of the water system, Waldron said. Detections aren’t clustered in any particular area, he said, and positive results are found among homes with “non-detects.” Similar levels of TPH were also found in homes that did not receive Red Hill well water after the fuel leak in 2021, he said.

The Navy’s investigation team did consider other possibilities to explain the TPH detections. Those included the presence of TPH in the Waiawa well, which the Pearl Harbor area now relies on, residual jet fuel or additives in the system, the presence of pesticides and the introduction of some other containment during a water main break. But all those theories were deemed to be of low or extremely low likelihood.

Waldron said the Navy will continue to dig deeper to determine the source, including taking steps to minimize cross-contamination in the lab, increasing quality control measures and using “more sophisticated forensic techniques.”

On Thursday, EPA Drinking Water Manager Corine Li agreed that the current results don’t indicate the presence of JP-5 jet fuel and said her agency will be doing its own testing.

Some members of the Fuel Tank Advisory Committee and those who attended the meeting were not satisfied with the Navy’s lack of answers.

“It’s not low to the people suffering from symptoms,” committee member Ashley Nishihara said of the TPH levels. “You need to establish where it’s coming from.” 

Lacey Quintero, whose family was sickened by the fuel-tainted water and continues to struggle with health problems, called the Navy’s explanation “a comedy of lab errors.”

“If you really wanted to solve the problem, it wouldn’t been done two years ago,” she said. “You’re the Navy. You can do anything.”