Pearl Harbor residents continue to report oily sheens on their water three years after the jet fuel stored underground at Red Hill contaminated their water supply, sickening scores of people.

But Navy officials now say that the increased levels of petroleum hydrocarbons found in water samples taken last year were actually false positives caused by laboratory contamination during the testing process. 

Specifically, chlorine in the drinking water samples mixed with laboratory testing substances to cause those false positives, according to a 434-page technical memorandum released Thursday, laying out the Navy’s findings. 

The Navy said it has updated its testing method to neutralize the effect, and that it’s confident those so-called total petroleum hydrocarbons, or TPHs, did not come from any jet fuel leaks from the storage tanks at Red Hill.

It remains to be seen whether the Environmental Protection Agency, which in December urged the Navy to investigate the root cause of those TPHs, will fully endorse the military’s latest findings. 

Amy Miller, director of the EPA’s Enforcement and Compliance Assurance Division, said Thursday that the federal agency generally supports what she called the Navy’s hypothesis that false positives are to blame for the TPHs. 

But the agency hasn’t had a chance to review the Navy’s memorandum because it just received the report Wednesday.

“There’s a lot to unpack there,” Miller said Thursday. 

Her division remains mostly focused on working with the Navy to extend its drinking water monitoring program for an additional year after its two-year stint ended in February.

Miller declined to say Thursday whether the Navy’s extended monitoring plan would include more precise testing methods after the puzzling rise in TPH detection for samples taken in 2023 raised questions and concerns among many in the community.

The Navy collected some 658 water samples in February and March, and TPHs were detected in 31 of them, Navy environmental engineer Chris Waldron said during a media briefing Thursday. 

When engineers removed the chlorine from the water in those samples, only six contained TPH and those were also found to be false positives caused by laboratory containers, Waldron said.

Some area residents remain distrustful of the Navy’s findings. Tracey Contreras, a resident of Joint Base Pearl Harbor-Hickam, said that in her experience the Navy has often labeled positive test results as false positives.

“My water looks like milk. You can’t see through it. There’s bubbles in it. There’s sheen in it. I definitely won’t be drinking it,” Contreras said Thursday. Her family members get bloodshot eyes when they run out of bottled water to bathe and have to use the shower, she added.

“There’s still something in the water. I don’t know what it is.”