HONOLULU (AP) - Regulators are ordering the Navy to redo some of its plans to assess the threat its Red Hill fuel tanks pose to Honolulu's groundwater.
The U.S. Environmental Protection Agency and the state Department of Health sent a letter to the Navy dated Sept. 15. It says the military will need to gather sufficient data to establish likely groundwater flow directions beneath and around the tanks.
The agencies say the work is critical for limiting the risk to the drinking water from past and potential future fuel leaks.
The Navy stores fuel for military ships and aircraft in 20 underground tanks at Red Hill. The tanks sit on an aquifer that supplies a quarter of the water consumed in urban Honolulu.
The Navy detected a leak of 27,000 gallons from one tank in 2014.