The Board of Water Supply began drilling a new monitoring well in Halawa Valley this week that will help determine how much contamination there is in the aquifer from the Red Hill fuel leak.

The well, located behind the Halawa Correctional Facility, will serve as a testing tool to investigate underground geology and sample water from the aquifer for petroleum, and per- and polyfluorinated substances (PFAS), a group of chemicals that pose risks to human health and the environment.

Crews working on the well will drill approximately 320 feet, according to Adam Norris, a senior hydrogeologist at environmental consulting firm Intera, which is working on the project. The team estimates that at around 220 feet underground, it will encounter first groundwater, then will drill an additional 100 feet. Norris said the team also plans to screen the well in the bottom 20 feet to search for potential contaminants.

Once the well is installed, laboratory samples can be submitted for analysis of potential contaminants. The drilling will take several months to complete, Norris said.

Norris said the team already has drilled to 50 feet underground, and so far has not seen any signs of contamination. However, no samples have yet been sent for laboratory testing.

“As far as monitoring, we’ll do it as long as we have to (in order) to ensure protection of the water supply,” Norris said.

It is the second monitoring well drilled by BWS because of the Red Hill water crisis, when 20,000 gallons of fuel from the Navy’s underground Red Hill Fuel Farm leaked into the Navy’s water supply, which serves about 93,000 people, in November 2021. BWS said that testing from their first well has not detected any petroleum hydrocarbons.

Last November, BWS filed a $1.2 billion claim under the Federal Tort Claims Act with the Navy to recover costs associated with the agency’s response to the water crisis, which included shutting down its Halawa Shaft facility — one of Oahu’s four main water supply shafts.

“(The Halawa Shaft facility) is not operating. It’s not pumping water into our system, and it won’t until we can be sure that if we turn this source on that we won’t be inadvertently sending hydrocarbon contaminated water into the water system over in Honolulu, or contamination from PFAS contaminants,” BWS manager and chief engineer Ernest Lau said at a news conference Wednesday.

Lau said that there’s a whole area of Halawa Valley that doesn’t have monitoring or test wells, and that BWS’s plans to drill more monitoring wells in this area will fill a “lack of basic information about what’s happening underground.” But collecting this information will likely take years, Lau said.

“Right now, it’s this kind of transition toward investigation and remediation, so a lot of that effort is going to be monitoring wells, continuous testing, and contaminant transport modeling,” Lau said. “It’s going to be years and years.”

BWS is planning to drill more monitoring wells in Halawa Valley across the Moanalua Freeway at Ala Puumalu Park, Halawa District Park, and the state Department of Agriculture’s Animal Quarantine Station, as well as several on the Moanalua Golf Course. These new wells, in addition to a new exploratory well, will be funded by $10 million that the state appropriated to BWS during last year’s legislative session.

Drilling for the new exploratory well will begin this year at the BWS Aiea 497 Reservoir site, where water will be sampled.

“If it produces enough water and the water’s high quality, no contaminants in it, then we’ll proceed toward designing the permanent well facility,” Lau said.

If the exploratory well becomes a permanent well facility, it’ll take between three and five years for it to become operational. The long design and construction time period, Lau says, is the “challenge” of doing new wells.

In the meantime, Lau said that BWS will look at alternative water source development options, just in case the determination is that turning Halawa Shaft back on will invite contaminants into the larger water supply.

In addition to the shaft closure and the installation of additional monitoring wells, BWS implemented enhanced water quality testing and temporarily increased its reliance on other water sources — expenses it hopes to get covered through its $1.2 billion FTCA claim.

“The intent is to recover costs from the Navy for all of this, because if it wasn’t for this World War II relic called Red Hill built over 80 years ago, all of this effort wouldn’t have to be done,” Lau said. “We don’t want the Navy to forget this, and to suddenly try to reduce their level of effort and not put any resources, including money, toward it. They need to clean up this resource that they’ve contaminated.”

Last week, an increase in complaints of tap water and air quality issues from Navy water system users prompted the state Department of Health to order the Navy to test Waiawa Shaft. The Navy said it tested the shaft on Jan. 30, with results coming back negative.

“I think they need to look at it much more closely and take it very seriously. I think they’re saying they’re taking it very seriously, but this is two years later, and they’re having low level detections across many locations in their water system,” Lau said. “You’ll see detections all over their water system where they’re testing, so there’s something there.”