Sunday, February 13, 2011

February 13, 2011 : Exxon Valdez Oil Spill

Exxon Valdez Oil Spill

The Exxon Valdez oil spill 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 (41,000 to 119,000 m3) of crude oil. It is considered to be one of the most devastating human-caused environmental disasters. As significant as the Valdez spill was—the largest ever in U.S. waters until the 2010 Deepwater Horizon oil spill—it ranks well down on the list of the world's largest oil spills 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. The oil, originally extracted at the Prudhoe Bay oil field, eventually covered 1,300 miles (2,100 km) of coastline, and 11,000 square miles (28,000 km2) of ocean. Then Exxon CEO, Lawrence G. Rawl, shaped the company's response.

Exxon Valdez left the Valdez oil terminal in Alaska at 9:12 pm on March 23, 1989, bound for Long Beach, California. The ship was under the control of Shipmaster Joseph Jeffrey Hazelwood. The outbound shipping lane was obstructed with small icebergs (possibly from the nearby Columbia Glacier), so Hazelwood got permission from the Coast Guard to go out through the inbound lane. Following the maneuver and sometime after 11 p.m., Hazelwood left Third Mate Gregory Cousins in charge of the wheel house and Able Seaman Robert Kagan at the helm. Neither man had been given his mandatory six hours off duty before beginning his 12-hour watch. The ship was on autopilot, using the navigation system installed by the company that constructed the ship. The ship struck Bligh Reef at around 12:04 a.m. March 24, 1989.

According to official reports, the ship was carrying approximately 55 million US gallons (210,000 m3) of oil, of which about 11 to 32 million US gallons (42,000 to 120,000 m3) were spilled into the Prince William Sound. A figure of 11 million US gallons (42,000 m3) was a commonly accepted estimate of the spill's volume and has been used by the State of Alaska's Exxon Valdez Oil Spill Trustee Council, the National Oceanic and Atmospheric Administration and environmental groups such as Greenpeace and the Sierra Club. Some groups, such as Defenders of Wildlife, dispute the official estimates, maintaining that the volume of the spill has been underreported. Alternative calculations, based on an assumption that the sea water rather than oil was drained from the damaged tanks, estimate the total to have been 25 to 32 million US gallons (95,000 to 120,000 m3).

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