Pearl Harbor was once known as Oahu's "bread basket" because it was such an important fishing area, teeming with ocean life. But since the construction of the iconic U.S. military base, the pristine harbor has been marred by environmental disaster.
The 12,600 acres of land and water that make up the Pearl Harbor Naval Complex were added to the Environmental Protection Agency's National Priority List of hazardous waste sites in 1992. This list identified the area as a Superfund site, or one that could harm local people or ecosystems due to hazardous waste. In 1998, the health department had issued an advisory to warn people against eating shellfish and fish caught in Pearl Harbor.
One of the base's more than 700 documented areas of contamination sits beneath Joint Base Pearl Harbor-Hickam's Halawa-Main Gate. There, bunker fuel and other petroleum products -- some of which the Navy says date back to World War II -- have been leaking from a tank farm and collecting in a large underground plume for decades.
Current estimates put the amount of spilled fuel at around 5 million gallons, or nearly half the volume of the 1989 Exxon Valdez oil spill in Alaska, Hawaii News Now reported earlier this month. The plume is approximately 20 acres, or 15 football fields, in size, according to the Navy.