The goopy leftovers of the Exxon Valdez oil spill have lingered on some of Alaska's beaches for an entire generation, in some cases as fresh as they were just days after the spill.
That's according to Gail Irvine, whose research on the shores of Katmai and Kenai Fjords national parks for the U.S. Geological Survey highlights the persistence of the crude oil that gushed from the tanker 25 years ago on March 24, 1989.
Some of that oil turned into a time capsule of the tragedy as it drifted over the ocean, sealed in its own protective crust like mayonnaise left too long on the counter, said Irvine. That brown emulsion, called "mousse," washed onto beaches far from the spill, oozing between the "cobblestone armor" where collections of boulders had locked themselves into place. The mousse seeped into the gravel beneath those rocks, further sealed into a world without oxygen and microbes to break it down.
Irvine has studied about 70 of those protective rocks for two decades, returning to their location every handful of years and using GPS and photos to confirm their identity. Some are located on five Katmai beaches along Shelikof Strait more than 250 miles from the spill site. The rest are at a single site within Kenai Fjords National Park and more than 140 miles from the spill site.
"We're studying the behavior of boulders," Irvine joked, but said seriously that there's not much behavior to study. Nearly all the rocks have been surprisingly stable, hardly moving at all over the years.
Lab results show that oil at most of the sites is chemically similar to what it was just 11 days after the spill, when it was drifting westward, sometimes for weeks before it made landfall. The oil can extend well below the surface, according to "dipstones" that are used like the dipsticks in a car to gauge the oil's depth.
The oil being studied amounts to a trace of the millions of gallons originally spilled, researchers have cautioned. And "results from the sites cannot be simply extrapolated to the entire spill area," according to an announcement of Irvine's findings by the American Geophysical Union. Whether anything should be done about that oil is up for debate. The persistent stuff can seep into the water, testing has shown, and toxins have occasionally been absorbed by mussels, though at low levels.
The possibility of a cleanup might be made more possible if Exxon Mobil Corp. pays the $92 million in costs the state and federal governments demanded in 2006, part of an effort to collect payment for unexpected damage from the spill.
In addition to the lingering oil, the the damage extends to some of the animals affected. Just 13 of 32 animal populations and habitats are considered recovered or very likely recovered, while two are considered not recovering, Pacific herring and pigeon guillemots. Also, one pod of killer whales is not considered recovering, while another is.
So far, Exxon has refused to pay, but the state and federal government have not sued to force the company's hand, as they should, said Rick Steiner, who was a marine conservation professor in Cordova with the University of Alaska when the spill occurred.
Even before that money is seen, the beaches should be injected with oxygen compounds that are basically hydrogen peroxide and other nutrients -- something that could be done without hurting the environment -- to speed up the oil's breakdown as soon as possible, he said.
"I don't buy the idea that the best thing we can do is stand by and watch," he said.
Irvine and other scientists who have studied the lingering oil and other effects said disturbing the beaches with large-scale cleanups might cause more harm than good, in part because workers would trample habitat.
Perhaps $5 million of the $92 million -- if it ever reaches state and federal hands -- could be set aside for continued monitoring of the beaches for years to come, rather than paying for a potentially risky cleanup, said Stanley "Jeep" Rice, who has tracked the effects of the spill since the beginning, first as a researcher with the National Marine Fisheries Services, and now in retirement.
He would have advocated for a full cleanup of the lingering oil years ago, but not now that nature has already done much of the work of degrading it, he said.
Perhaps many of the millions of dollars left over could go to a land-purchasing program to acquire more habitat for animals injured by the spill, said Jeff Short, who worked with Rice for many years at Auke Bay Laboratories in Juneau.
One thing's for certain, said Irvine, "Prevention is the key to reducing this kind of event, and then preventing oil from getting on shore in places where it might persist is an additional lesson."
Contact Alex DeMarban alex(at)alaskadispatch.com