The Navy is drilling for oil at Pearl Harbor, but it’s not likely to ease the island’s energy crunch.
The oil – hundreds of thousands of gallons of it – wasn’t deposited in the Cretaceous era, but dates back just half a century, more or less. Power plants built in the 1940s, leaky underground storage tanks, pipelines and other military-industrial installations all helped feed large plumes of pollution – including one covering 20 acres – that now spread over a shallow, perched aquifer below the Pearl Harbor Naval Complex on O`ahu. When the Navy began to size up the extent of pollution at Pearl Harbor a decade ago, it found diesel fuel, Navy special fuel oil (NSFO), and residual oil all present in the subsurface soils and groundwater.
One day, the Navy hopes to shrink the oil plumes enough to eliminate them from among the several sources of pollution in Pearl Harbor. At an October 24 meeting of the Pearl Harbor Restoration Advisory Board, Liane Rosen, a remedial project manager for the Navy’s Pacific Division, described three new sites where the Navy will build recovery facilities to pull petroleum from the groundwater. The new systems, to be built at Hotel Pier, Magazine Loch, and Quarry Loch, will double the Navy’s current oil extraction efforts in the Pearl Harbor Navy Complex, which in 1992 was added to the National Priority List (better known as the list of Superfund sites).
Quarry Loch has an estimated 70,000 gallons of “free-phase product” below it; oil “reserves” at Hotel Pier are between 2,500 and 17,000 gallons. The oil plume below Magazine Loch covers about 20 acres. The petroleum generally lies less than a dozen feet below the ground, and plans call for sumps and trenches to extract the oil.
At an existing facility known as Building 8, a 100-foot “bathtub” cut into the rock fills with petroleum-contaminated water. Belts are lowered into the soup of oil and water, and after they resurface, the thick, heavy, tar-like oil that clings to them is scraped off and pumped to a storage tank where it is held until it can be recycled at a civilian facility off site.
Just a short 60 feet below this polluted perched aquifer of brackish water sits the Honolulu-Pearl Harbor Basal Aquifer, the island’s primary source of drinking water. But despite the petroleum’s proximity to the drinking water aquifer, the Navy says the basal aquifer is not threatened by it, since the petroleum plumes are at an elevation that falls below the Department of Health’s Underground Injection Control line, which defines the boundary between drinking and non-drinking water sources. Also, since the oil floats on top of the perched aquifer, it’s unlikely that any of it would migrate down through the brackish water and the substrate separating the perched aquifer from the drinking water aquifer.
The larger worry is that the underground plumes may be affecting Pearl Harbor’s sediment and marine life as it slowly leaches into the harbor. At Hotel Pier, diesel and oil migrates into the harbor through storm drain pipelines, “creating a sheen on the water,” a Navy fact sheet states.
The harbor is habitat for up to three species of sea turtle (the green, hawskbill, and loggerhead). Four endemic and endangered water birds are found on the Pearl Harbor National Wildlife Refuge, and the pueo, Hawai`i’s short-eared owl, listed as endangered on O`ahu, hunts in the area.
“The quiet waters in the upper regions of all the Pearl Harbor lochs provide excellent habitat for the Hawaiian anchovy, nehu (Encrasicholina purpurea), a species used as a baitfish in the offshore tuna aku, fishery. This species is the most important baitfish resource in Hawaii, and Pearl Harbor provides a primary harvesting area within the state. For this reason, the U.S. Navy issues permits for insured commercial aku boats to collect baitfish from certain regions of Pearl Harbor,” states an August 2000 Navy report. Shorebirds, plankton, diatoms, sea anemones, feather duster worms, other fish species, and larvae from many different animals may be harmed by the harbor’s petroleum hydrocarbons, toxic organic compounds, and heavy metals, siltation and high nutrient levels, the report goes on to say. In March 1999, the state Department of Health published brochures in six foreign languages, warning Hawai`i’s non-English speaking population that “fish caught in some Honolulu [specifically, Pearl Harbor] waters may contain chemicals (including PCBs and pesticides) that are hazardous to your health if consumed of a long period of time.” Participants and the October RAB meeting raised concerns that, while few people fish in the harbor, fish contaminated by the harbor may swim to other areas that are regularly fished. A Navy-sponsored study of the chemicals found in Pearl Harbor’s sediment and fish should be completed within the year, says Navy public information officer William Roome.
In the meantime, as the Navy builds new extraction facilities, it will continue to remove the oil at three existing stations located in and around Pearl Harbor’s shipyard. As of December, it has removed more than 35,000 gallons of petroleum products from the three sites.
— Teresa Dawson
Volume 11, Number 9 March 2001
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