occurred in Prince William Sound, Alaska, on March 24, 1989, when the Exxon Valdez, an oil tanker bound for Long Beach, California, struck Prince William Sound's Bligh Reef and spilled 260,000 to 750,000 barrels of crude oil. It is considered to be one of the most devastating human-caused environmental disasters. The Valdez spill was the largest ever in U.S. waters until the 2010 Deepwater Horizon oil spill, in terms of volume released. However, Prince William Sound's remote location, accessible only by helicopter, plane, and boat, made government and industry response efforts difficult and severely taxed existing plans for response. The region is a habitat for salmon, sea otters, seals and seabirds. Lead to Oil Pollution Act of 1980.