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America's 10 worst man-made environmental disasters

By: Laura Moss on June 14, 2010, 12:50 p.m.
Man standing in oil from 1989 Exxon Valdez spill in Alaska.

Photo: John Gaps III/AP

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Exxon Valdez oil spill

Perhaps the most notorious man-made environmental disaster in American history until recently, the 1989 Exxon Valdez oil spill devastated the Alaskan coast. When the Exxon Valdez supertanker hit a reef in Prince William Sound, 11 of its cargo tanks ruptured, dumping 10.8 million gallons of crude that eventually covered 11,000 miles of ocean.

Cleanup began immediately, but despite thousands of personnel helping over the next two years, the spill still hasn’t been fully cleaned up 20 years later. In 2001, a survey found oil at 58 percent of the 91 sites assessed, and oil remains a few inches below the surface on many of Alaska’s beaches.

Responders found carcasses of more than 35,000 birds and 1,000 sea otters. These discoveries were considered to be a fraction of the animal death toll because carcasses typically sink to the seabed. It’s estimated that 250,000 seabirds, 2,800 sea otters, 300 harbor seals, 250 bald eagles and up to 22 killer whales died along with billions of salmon and herring eggs. A 2006 study found that exposure to Exxon Valdez oil still impacts many shore-dwelling animals — otters have yet to reinhabit Herring Bay, and their overall numbers have declined.

The repaired Exxon Valdez was renamed the SeaRiver Mediterranean, and, although it is banned from Alaskan waters, the tanker still carries oil around the world.