Weathering Patterns of Oil Residues Eight Years after the Exxon Valdez Oil Spill

Eight years after the Exxon Valdez spill, oil residues in Prince William Sound, Alaska ranged from moderately to extremely weathered. The least weathered residues were found in samples collected from gravel beaches with well-established armor. There had been little to no change in weathering stage for the oil from these sites since 1994. There was evidence of some physical erosion, but little chemical change for this deeply penetrated oil. In contrast, most other oil residues have increased in weathering, compared to 1994. Only one asphalt pavement was at a moderate weathering stage. All other samples contained hydrocarbons which were at advanced or extreme weathering stages.