The sound of a sound recovering?
So did three years of Exxon-sponsored scouring, and 13 years of wind and
waves, actually fix Prince William Sound? Thomas Cirigliano, a spokesman
for ExxonMobil, as Exxon is now called, says yes. "Are the animals and
plants that are indigenous to Prince William Sound present and thriving,
doing the things they should be doing?" Under that definition, he concludes,
"Prince William Sound is absolutely recovered."
This gull was probably a goner. "Oiled" feathers don't insulate, and when the bird cleans itself, it may eat a lethal dose of hydrocarbons. Note oily ocean in background. Courtesy Exxon Valdez Oil Spill Trustee Council.
The Exxon Valdez Oil Spill Trustee Council takes a more cautious slant in its most recent report:
"Ten years after the Exxon Valdez oil spill, it is clear that many fish and wildlife species injured by the spill have not fully recovered. It is less clear, however, what role oil plays in the inability of some populations to bounce back."
Specifically, the Trustees list eight species, including harbor seals, as "not recovering," another eight as "recovering," and only six as "recovered."
What does the government think? In sterling bureaucratese, a National Oceanic and Atmospheric Administration study said the hard-hit intertidal communities in Prince William Sound were, "recovering, but not recovered."
The long dispute over the health of the sound quickly slides into a nasty back-and-forth. While the Trustees imply that researchers funded by the oil industry are biased, Cirigliano says, "We take issue with some statements made by the so-called Valdez Trustees, some of the researchers who are using the billion dollars that Exxon paid for research in Prince William Sound, regarding their definition of recovery." (The actual figure is $900 million.)
It's a legitimate scientific dispute. The trustees measure success by a return to pre-spill conditions, but Cirigliano says that's an unrealistic -- even impossible -- standard since "Nobody has any accurate numbers" on species before the spill. (Environmentalists, who argued for such "baseline" studies before the Alaska pipeline was built, counter that ignorance should not be an excuse.)
You can never step in the same sound twice
But there's another, perhaps more fundamental problem:
ecosystems constantly change. "Harbor seals were in serious decline prior
to the spill, and that level of decline has continued," says Cirigliano.
"The trustees claim that when harbor seals return to their number before
the spill, then they will be taken off the ['not recovered'] list. But
clearly there is something that affects harbor seals that has nothing
to do with the spill."
A dead murrelet, one of the hardest-hit sea birds in the Valdez spill.
Courtesy Exxon Valdez Oil Spill Trustee Council.
David Page, a professor of chemistry and biochemistry at Bowdoin College, elaborates: "It will never be 1989 in Prince William Sound again. There has been a major warming trend in Alaska over the last 12 years... and changes in temperature have a profound effect on ecological relationships."
A return-to-the-past standard, Page says, "is not only scientifically incorrect, but is incorrect with respect to federal regulations in the Clean Water Act, which define recovery as being what the spill zone would have been had the spill not occurred."
Ecologically, he says, "Spinning the clock backwards makes absolutely no sense to me."
Page, who has been studying oil spills for 28 years, with funding from governments, Exxon and other oil companies, says, "12 years is a very long time in the life of an oil spill. I think at the end of the day, the question of which species have now recovered, and which have not, is ... related to other factors.".
One possibility, Page says, is natural oil seeps. "Petroleum is a natural product, and there are lots of places where it pours into the environment. A lot of hydrocarbons are available to the biota, carried in from seeps east of Prince William Sound." (Want more on finding petroleum?)
In fact, a 2002 National Academy of Sciences report ""Oil in the Sea II" found that natural sources predominate both in the United States and globally. Seepage of crude oil from geologic formations below the seafloor in North America is estimated at more than 160,000 metric tons. Globally, the annual figure is 600,000 tons.
So more than 60 percent of the petroleum entering North American waters, and more than 45 percent of that entering waters worldwide, comes from natural seeps. And that could explain why trustee-sponsored biopsies of dead sea otters in Prince William Sound have found what Mundy calls, "compromised livers and enzyme systems that indicate exposure to oil."
With hot water and high-pressure hoses, Exxon employees cleaned
the beaches, washing the oil into the water, where it was mopped up and,
we trust, refined into something useful. Photo from NOAA
Drinking old oil?
Alternatively, the contamination could reflect past
industrial activity. Page says copper mines, canneries and sawmills that
were "all over the place in the spill zone" polluted shoreline sediments
with "high levels of the same kind of hydrocarbons that caused the effects
the trustees say are due to the oil spill."
Ongoing, low-level pollution from ships and fishing boats "is now far more important" than Valdez residues, Page argues. "It's fair to say that what is being attributed to the spill, as long-term, lingering effects, when you look closely, objectively, you find there are other, more plausible explanations." Mundy acknowledges that natural seeps and low-level sources complicate the scientific effort. "Of course, making the linkage, a chain of custody from Exxon Valdez pockets in Prince William Sound to these animals, that's difficult if not impossible to do now. We know the [Valdez] oil is there, that it does get into clams that the sea otters eat ... it's highly plausible that organisms such as these continue to be exposed, and the populations in those areas are not yet the same as they were before the spill."
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