In 1989, how many barrels of oil did the Exxon Valdez spill off the coast of Alaska?

The Exxon Valdez oil spill occurred in Prince William Sound, Alaska, March 24, 1989, when Exxon Valdez, an oil tanker owned by Exxon Shipping Company, bound for Long Beach, California, struck Prince William Sound's Bligh Reef, 1.5 mi (2.4 km) west of Tatitlek, Alaska, at 12:04 a.m.local time and spilled 10.8 million US gallons (260,000 bbl) (or 37,000 metric tonnes) of crude oil over the next few days. It is considered to be one of the worst human-caused environmental disasters. The Valdez spill is the second largest in US waters, after the 2010 Deepwater Horizon oil spill, in terms of volume released.

Prince William Sound's remote location, accessible only by helicopter, plane, or boat, made government and industry response efforts difficult and severely taxed existing response plans. The region is a habitat for salmon, sea otters, seals and seabirds. The oil, originally extracted at the Prudhoe Bay Oil Field, eventually affected 1,300 miles (2,100 km) of coastline, of which 200 miles (320 km) were heavily or moderately oiled. The Valdez oil spill was the "worst oil spill in U.S. waters" until BP's 2010 Deepwater Horizon oil spill.