ANCHORAGE, Alaska (AP) -- More fresh oil remains in Prince William Sound than anybody would have imagined when the Exxon Valdez ran aground in 1989 in the nation's worst oil spill ever, officials said Wednesday.
''Originally I think everyone thought within a pretty short time the toxic portion of the oil would dissipate and what was left would be inert. That is not the case,'' said Molly McCammon, executive director of the Exxon Valdez Oil Spill Trustee Council. ''They're finding a lot more subsurface oil that is still fresh and toxic after 12 years.''
Crews spent this last summer overturning rocks and digging holes in the shoreline of Snug Harbor -- 55 miles southwest of Bligh Reef where the oil tanker ran aground -- as part of a National Marine Fisheries Service survey to determine how much oil remains following the 11-million gallon spill.
Scientists have found oil in about 5 miles of 70 miles of shoreline that was either heavily or moderately oiled when the spill occurred or shortly thereafter. They should know in the next few months how much oil is left.
A 1994 NMFS study estimated that about 70 percent of the spilled oil had dissipated into the air or biodegraded in the ocean or on shore, and about 14 percent was recovered in the cleanup process.
The study estimated that about 13 percent remained in the mud and sand, and about 2 percent remained on the beaches.
Jeffrey Short, a NMFS research chemist doing the new survey, predicts much less oil will be found this time around.
Sea otters and sea ducks that live in the sound continue to show an elevated level of an enzyme that comes from hydrocarbon exposure, McCammon said. The enzyme has been traced to the Exxon Valdez oil.
Exposure to oil likely contributed to the crash of the Pacific herring population because it stressed the fish and made them susceptible to disease, McCammon said. A commercial herring harvest has not been held since 1993.
Short doubts that the remaining oil is a factor in the recent fluctuations in salmon populations. But he said scientists are surprised to find how little oil -- one part per billion -- it takes to kill fish eggs.
Scientists also are surprised that most of the remaining oil was found in the lower intertidal area. They expected to find oil higher up on the beaches where the spill made landfall in 1989.
Short said waves the first year probably broke up oil that coated the upper shoreline, sending smaller deposits to the lower beach where it settled 2 to 10 inches deep.
''It looks like it did in 1989, black and goopy,'' he said.
While the oil looks the same, the Prince William Sound community of Cordova, where half of households rely on commercial fishing and processing, has changed a lot, said Riki Ott, a marine toxicologist who co-founded the Alaska Forum for Environmental Responsibility in 1994.
Herring have not reproduced since the spill and pink salmon populations crashed in 1992 and 1993. About a third of the fishing families left and those that remain in the town of 2,500 people are struggling.
''We just can't shake the oil spill blues,'' Ott said.
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