The Honolulu Board of Water supply says it has detected petroleum-related chemicals in a monitoring well in Moanalua Valley, elevating concerns that fuel contamination from the Navy’s Red Hill fuel facility is traveling through the aquifer and putting a major source of drinking water for southern Oahu at risk.

The BWS said that it detected total petroleum hydrocarbons in water samples that were tested at the well, indicating the presence of fuel, as well as polycyclic aromatic hydrocarbons. PAH’s are a class of chemicals that occur naturally in coal, crude oil and gasoline, and are also produced when coal, oil, gas, wood, garbage and tobacco are burned, according to BWS.

“The recent contaminant detections in our DH-43 monitoring well are warnings that we cannot ignore,” said BWS Manager and Chief Engineer Ernest Lau in a press release. “Our precious and irreplaceable water resources are at risk of further contamination every day the fuel remains in the Red Hill tanks. We urge the Navy to expeditiously defuel and permanently close the Red Hill facility – Ola I Ka Wai,” which means water is life.

The monitoring well was installed to check for the possible presence and migration of contaminants in the groundwater and does not mean that Oahu’s drinking water system is contaminated. The BWS said that it had met with the Hawaii Department of Health and U.S. Environmental Protection Agency and that there is agreement that the low levels detected are not expected to pose a health hazard.

“However, while not a current health emergency, it needs attention and continued monitoring,” according to BWS’ press release.

More investigation is also needed to tell whether the source of the contamination is the Navy’s Red Hill fuel facility, which is in the process of being shut down after leaks from the underground tanks and pipelines last year contaminated the Navy’s drinking water system.