In January 2014 the U.S. Navy reported to the Hawaii Department of Health that approximately 27,000 gallons (102,000 liters) of jet fuel had leaked from an underground tank at the Red Hill Bulk Fuel Storage Facility, which supplies fuel to Pearl Harbor naval base. The leak raised serious concerns over the risk of contamination spreading to important water supplies. The fuel facility consists of 20 tanks and is located just 100 feet (30 meters) above an aquifer that hundreds of thousands of residents living in and around Honolulu depend upon for their fresh drinking water.[1] Officials from the Hawaii Department of Health and Honolulu Board of Water Supply inspected the fuel facility and were able to see the leaking tank, tank 5, first-hand. Documents filed with the health department showed that there had been a previous leak at the Red Hill facility in 2001-2002 with efforts to undertake follow-up monitoring. Reports indicated that even at that time the state had doubts over the adequacy of the monitoring system for preventing fuel from getting into drinking water. Detecting and repairing a leak from underground tanks is far more difficult than with above-ground facilities.[2] In April 2014, as contractors began to inspect the tank and the Navy sought a contractor to ‘define the nature, extent and magnitude of soil and groundwater contamination beneath Tank 5’, Honolulu City Council members joined a chorus of officials urging the Navy to make improvements to prevent what the Honolulu Board of Water Supply warned could be a serious hazard to the water supply if a powerful earthquake in the area were to disturb the ground. The Board of Water Supply and Hawaii Department of Health said that, to date, there were no indications that fuel had contaminated the groundwater aquifer, but elevated levels of hydrocarbons had been detected in soil vapor samples at nearby monitoring points. There were particular concerns over the possible threat to two wells, Halawa Shaft and and Moanalua Shaft, accounting for 25 per cent of the water supply to the area between the residential neighbourhoods of Moana-lua and Hawaii Kai. And a long history of fuel leaks from the Red Hill facility came to light. Water officials said the Navy had reported dozens of fuel releases, adding up to a volume of about 1.2 million gallons (4.45 million liters), but the Health Department had not informed Board of Water Supply officials until the most recent leak was being discussed.[3] A Navy report from 2010 had suggested that fuel contamination might be moving in the direction of country drinking water supplies.

In June 2014 Ernest Lau, chief engineer at the Board of Water Supply, expressed concern at the slow pace of action to address the jet fuel leak. The process of draining the tank and airing out the fumes had taken several weeks; inspection of the tank walls and bottom could only commence only after this had been completed. Lau and other health officials said that a more extensive well monitoring programme might be needed and that only two of four test wells, specified in a USD1.5 million contract awarded on 22nd May, had been drilled. The Health Department was expected to release an ‘enforcement remedy’ for the Navy to address contamination concerns but there was uncertainty over whether such an agreement would be legally binding. Red Hill Bulk Fuel Storage Facility was exempt from federal leak detection and prevention requirements that most underground fuel systems had been subject to since the 1980s. It was noted that hydrocarbon levels in soil vapor beneath Tank 5 had jumped to 225,000 parts per billion at the time the leak was detected in January 2014, triple the highest ever level recorded under the tank since sampling began in 2008.[4]

On June, in the course of testing to determine whether air could flow through the tank wall, workers found three tiny holes, too small to see with the naked eye, which could be the source of the leak. More information about the long history of fuel leaks emerged. Over the 70 years since construction of the facility all of the 20 tanks had leaked. Petroleum-contaminated rock was found under 19 of the tanks while Navy records indicated that the remaining tank had leaked at some point. Gary Gill, the state Department of Health’s deputy director for the environment said the department knew that groundwater immediately below the tanks had been contaminated by petroleum but did not know how far or in which direction the contamination plume had travelled.[5] The Navy pinpointed the source of the fuel leak upon completion of ‘vacuum-box’ testing to find out where air was flowing under the wall of the underground tank. Fifteen defects, tiny holes that might have been caused by recent maintenance works, were discovered. A total of 45 areas of Tank 5’s walls appeared to be ‘suspect’.[6] 21st February 2018 marked a victory for the Sierra Club’s research, campaigning and advocacy work to address the Red Hill fuel leaks and protect water supplies from contamination. A court ruled in favour of the Sierra Club, finding that the state’s exemption of the Red Hill fuel tanks violates state law. The Sierra Club lawsuit was based upon a 1992 state law directing the Health Department to enact rules requiring the upgrading of existing underground storage tanks to prevent releases of petroleum into the environment. Instead of complying with this mandate the Department of Health had exempted Red Hill from regulation, in spite of its admission that “the storage of up to 187 million gallons of fuel, 100 feet above a drinking water resource is inherently dangerous”. The new ruling meant that the fuel tanks must be brought into compliance with state law. Sierra Club of Hawai’i director Marti Townsend said: “This is a big deal. The Navy can no longer skirt our laws. Its time to fix up the Red Hill fuel tanks or shut them down…The future of O’ahu’s drinking water is looking much clearer.”[7] In December 2018 Sierra Club of Hawaiʻi published a fact sheet about the Red Hill fuel tanks. Almost five years after the major leak was discovered no leaked fuel had been located or cleaned up. The tanks had not been fixed and it could not be guaranteed that more leaks would not occur. The condition of the fuel tanks was worse than anticipated. Areas of the steel walls had thinned far more than predicted. Originally the steel walls were 0.12 inches (6.35mm) wide. The thinnest samples were less than a third of the original width measuring just 0.079 inches (2mm). The Sierra Club disagreed with the Navy’s preferred option of maintaining the current tank system. Its proposals, such as re-coating the bottom of the tanks with epoxy, were almost identical to the repair efforts over the preceding 13 years, i.e. the least protective and least expensive options. Concerned that the corroding tank walls could result in further fuels leaks, and noting the lack of a plan to ensure protection of water sources, the Sierra Club argued that the Red Hill facility should be shut down and relocated far away from drinking water supplies.[8] Lack of geological knowledge about the ground under the fuel tanks resulted in a lack of understanding about water flows and inability to predict how leaks would spread. AECOM, an international firm with many military contracts, developed a computer model of what the ground under the facility might look like and some deep holes were drilled in an attempt to learn more about the geology under the facility, but it is vast and complex and there are still important gaps in knowledge. A 2008 study conducted by Ohio-based TEC Inc. spent USD120,000 researching options for secondary containment and leak detection technology. This study also provided helpful information about the leak history. After the 2014 leak the Red Hill Fuel Storage Facility Task Force was established, a body composed of the Hawaii Department of Health, the Environmental Protection Agency (EPA), US Navy, Honolulu Board of Water Supply, the Department of Land and Natural Resources, one member from the state Senate and two members from the community. The task force studied the 2008 report and other documents and made a number of recommendations related to transparency and the need for more diligent research, including a scientific peer review and evaluation of sampling and detection methods. Letters to the US Navy from the EPA, Hawaii Department of Health and Hawaii Board of Water Supply outlined concerns that these recommendations had not been adequately addressed.[9] In March 2019 Honolulu City Council called on regulators to ensure better protection against water contamination from Red Hill fuel tank leaks. Council members agreed with the Honolulu Board of Water Supply that the Navy’s plan for a single-wall upgrade of 18 deteriorating jet fuel tanks puts Honolulu’s water supplies at risk. A resolution was passed urging the EPA and Hawaii Health Department to require the Navy to either use a secondary containment tank or relocate the fuel storage facility altogether.[10]

Built in 1940-43 Red Hill Bulk Fuel Storage Facility is located in a cavity excavated inside Red Hill. Situated under 100 feet (30 meters) of volcanic rock it is the largest underground storage tank facility in the US. Twenty cylindrical steel-lined underground tanks, encased in concrete, can each hold 12.5 million gallons (47.3 million liters) of fuel and the facility’s total fuel storage capacity is 250 million gallons (946 million liters). The 20 fuel tanks are 20 feet (6 meters) in diameter and 250 feet (26 meters) high, about the height of a 20-storey building. Owned by the U.S. Navy, Red Hill supports military operations in the Pacific; three pipelines 4 kilometers in length run to fuelling piers at Pearl Harbor. The facility stores and dispenses three types of petroleum fuel: marine diesel for ship and two types of jet fuel, JP-5 and JP-8.[1]