The state Department of Health announced Tuesday that it has conditionally approved the military’s plan to defuel the main tanks of the Navy’s underground Red Hill Bulk Fuel Storage Facility beginning Monday.

It was the last pending item before the Joint Task Force Red Hill, the military organization stood up to remove fuel from the facility, can begin draining the tanks.

The conditional approval is contingent on the military’s adherence to the plan as well as other requirements set forth by DOH in a conditional approval letter to JTF-RH commander Vice Adm. John Wade. The requirements outlined in the letter include daily updates from JTF-RH, as well as requiring the military to allow access to DOH staff to oversee the defueling.

“Today’s conditional approval marks an important milestone in the process that will ultimately result in permanent closure of the Red Hill Facility and remediation of our aquifer,” said DOH Deputy Director of Environmental Health Kathleen Ho in a media release. “Many people have worked for many months to reach this milestone, and we appreciate and fully expect that the Joint Task Force will continue to uphold its commitments to the people of Hawaii and our environment.”

The Red Hill tanks sit just 100 feet above a critical aquifer most of Honolulu relies on for clean water. Local health officials have warned that the aging World War-II era facility is a “time bomb” that threatens Oahu’s water supply, particularly after a 2014 spill at Red Hill.

Navy officials for years insisted that the facility was safe and that it was vital to supporting the operations of its Pacific Fleet.

But in November 2021, jet fuel from the facility leaked into the Navy’s Oahu water system, which serves 93,000 people, including military families and civilians in former military housing areas. After several months of resisting a Hawaii state emergency order to drain the tanks, in March 2022 Defense Secretary Lloyd Austin announced the military would defuel and permanently shutter the facility.

The military also acknowledged that despite its previous insistence the aging facility was safe, it had actually fallen into deep disrepair and that much of its infrastructure — including the pipelines connecting the tanks to Joint Base Pearl Harbor-Hickam — would require extensive repairs before the fuel could be safely removed without risking more spills and further threats to the aquifer.

In its news release, the DOH said officials oversaw completion of 297 repairs and enhancements needed for repacking and defueling by JTF-RH. It said the DOH also observed various spill drill exercises and the successful defueling of the four surge tanks in July and repacking of two of the facility’s three pipelines from August to September.

“We commend the leadership of the Department of Health in this ongoing crisis, and we want the public to know that my administration will continue to insist on transparency and accountability as the defueling of the bulk storage facility progresses,” Gov. Josh Green said in a statement.

“All of us in leadership positions — whether government, community organizations and, of course, the military — have to work together to ensure the water and the land at Red Hill and the aquifer under it, will be remediated properly and expeditiously. Clean water for future generations must be our shared goal,” the governor said.