Damage of Exxon Valdez endures
By Elizabeth Weise
Oil from the massive Exxon Valdez spill, which coated 1,200 miles of Alaskan coast when the tanker ran aground in March 1989, continues to threaten the damaged ecosystem there long after experts believed it would dissipate.
When the ship hit Bligh Reef, it released as much as 10.8 million gallons of crude oil into Alaska's pristine Prince William Sound and parts of the Gulf of Alaska. The spill was the largest in U.S. history, the Environmental Protection Agency says, and killed an untold number of fish, birds, seals and sea otters.
According to a study out Feb. 15 in the journal Environmental Science and Technology, scientists from the National Oceanic and Atmospheric Administration (NOAA), the U.S. Geological Survey and Alaskan agencies found that oil levels in the sands around the sound are much the same as they were when tests were done five years ago. The study says oil has seeped down 4 to 10 inches.
The oil is a continuing, "far-ranging" problem for fish and wildlife, says Kim Trust, science director of the Exxon Valdez Oil Spill Trustee Council, an Alaska-federal partnership that works to repair the environmental damage. A 2006 council report found that two species � Pacific herring and pigeon guillemots � are not recovering. Populations of clams and mussels are still affected by the lingering oil, as are sea otters and birds such as harlequin ducks and black oystercatchers.
The new report states that subsurface oil poses a contact hazard for foraging otters, ducks and shorebirds, creates a chronic source of low-level contamination, discourages subsistence and "degrades the wilderness character" of protected lands.
Exxon spokesman Mark Boudreaux said in an e-mail, "There have been nearly 350 conference presentations or publications in peer-reviewed journals. Based on that body of scientific evidence, it is clear that there have been no effects on the environment that remain ecologically significant."
Seventeen years ago, scientists predicted that the oil would be long gone by now. "We expected the natural decay rate was 25% a year. But very little of the oil actually disappeared," says Jeffrey Short, a NOAA research chemist. "What's left is going to be there a long time."
Instead, the researchers estimate, the oil is "weathering" away at a rate of 3% to 4% a year. "It will be readily detectable for decades," Short says.
Jennifer Culbertson, a marine ecologist at Boston University, is among the surprised. "The theory has been that on a rocky shore, it's not going to stay for that long, that waves will wash it away," she says.
Says Michael Baffrey of the Trustee Council: "We made a lot of assumptions about what would happen to the oil. A lot of those didn't play out."
As many as half a million birds were killed in the spill, the Alaska Department of Environmental Conservation says, including more than 150 bald eagles. As many as 4,500 sea otters died, the National Marine Fisheries Service says.
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