Twenty years ago, the single-hulled Exxon Valdez tanker collided with the Bligh Reef in Alaska, spilling 11 million gallons of crude oil into the pristine and ecologically significant Prince William Sound. The massive spill—caused by human error and lack of oversight—ruined one of America's most treasured natural areas and caused the deaths of millions of animals, including more than 3,000 sea otters, 300 harbor seals, 250,000 murres, 14 orcas, and countless fish and benthic invertebrates. Some species are still unrecovered today, and the environment remains blanketed in oil.
A 2009 status report from the Exxon Valdez Oil Spill Trustee Council states, "…Exxon Valdez oil persists in the environment and, in places, is nearly as toxic as it was the first few weeks after the spill." Although two decades have passed, as much as 16,000 gallons of oil persists in the Sound's intertidal zones, continuing to poison wildlife.
Animals such as the harlequin duck have been slow to recover and show elevated levels of polycyclic aromatic hydrocarbons from continued exposure to oil. The persistence of subsurface oils is particularly problematic for species like sea otters who dig for clams, exposing buried oil in the process. Pacific herring and the pigeon guillemot populations have still not recovered. The small AT1 population of orcas will likely become extinct, marking the death of a priceless genetic lineage and a complex society that has inhabited the region for thousands of years.
The Oil Pollution Act was unanimously passed by Congress in 1990 in response to public concern over the spill. The Act contains provisions to prevent similar catastrophes from occurring including a conversion of oil tankers to double-hulled, the establishment of spill contingency plans, and the creation of regional advisory councils to monitor the actions of the oil industry. While 79 percent of the global supertanker fleet has been replaced by vessels with two hulls, Exxon, the world's largest oil company, has kept using tankers with only one.