The Exxon Valdez oil spill was a major environmental disaster that occurred in Alaska's Prince William Sound on March 24, 1989. The spill occurred when Exxon Valdez, an oil supertanker owned by Exxon Shipping Company, bound for Long Beach, California, struck Prince William Sound's Bligh Reef, west of Tatitlek, Alaska, at 12:04 a.m. The tanker spilled more than (or 37,000 tonnes) of crude oil over the next few days. It is the costliest disaster ever with no direct human fatalities. Prince William Sound's remote location, accessible only by helicopter, plane, or boat, made government and industry response efforts difficult and made existing response plans especially hard to implement. The region is a habitat for salmon, sea otters, seals, and seabirds. The oil, extracted from the Prudhoe Bay Oil Field, eventually affected of coastline, of which were heavily or moderately oiled.

Spill

left|thumb|The [[Exxon Valdez a few hours after it was grounded.]]

Exxon Valdez was carrying of oil, of which approximately were spilled into the Prince William Sound. at 11:30 p.m. on March 22, 1989. Loading of crude oil was completed late in the day on the 23rd. The tanker left the terminal at 9:12 p.m., March 23, 1989 (the deck log shows that it was clear of the dock at 9:21p.m.), loaded with 53,094,510 gallons (1,264,155 barrels) of crude oil. Captain Joseph Hazelwood retired to his cabin at 9:25p.m. Harbor pilot William Murphy and Third Mate Gregory Cousins were on the bridge while the tanker was accompanied by a single tug for the passage through the Valdez Narrows – a journey of about 7 miles. The pilot left the bridge shortly after the vessel left the narrows, at 11:24p.m. At this point, the captain was called to the bridge. Cousins helped the pilot disembark from the vessel, leaving the captain as the only officer on the bridge. At 11:25p.m. Exxon Valdez reported that the pilot had left. The captain advised traffic control and the ship maneuvered out of the outbound traffic lane in the Traffic Separation Scheme (TSS) to avoid small icebergs; a common occurrence since the Columbia Glacier calved such icebergs nearby. The vessel was placed on a due south course and set on autopilot. At 11:47p.m. the vessel left the traffic lane's eastern boundary. Following the maneuver, Hazelwood departed the navigation bridge and retired to his stateroom for the night.

He left Third Mate Gregory Cousins in charge of the navigation bridge and Able Seaman Robert Kagan at the helm with instructions to the third mate to return to the southbound traffic lane in the TSS at a prearranged point. Third Mate Cousins had been on duty for six hours and was scheduled to be relieved by Second Mate Lloyd LeCain Jr. However, due to the long hours that the second mate had worked, Cousins was reluctant to wake him, and remained on duty. Cousins was the only officer on the bridge for most of the night, in violation of company policy. At around midnight on March 24, Cousins began to maneuver the vessel into the traffic lanes. At the same time, the lookout reported that the Bligh Reef light appeared far off the starboard bow at 45 degrees – this was problematic given that the light should have been off the port side. Cousins ordered a course change because the ship was in danger. Captain Hazelwood was phoned by Cousins, but before their conversation could finish, the ship grounded. At 12:04a.m., accompanied by what the helmsman and Cousins described as "a bumpy ride" and "six very sharp jolts" respectively, the ship ran hard aground on Bligh Reef.

Carried by its own momentum, the ship ended up perched on its middle on a pinnacle of rock. Eight out of 11 cargo holds were punctured. 5.8 million gallons of oil drained from the ship within three hours and 15 minutes. Thirty minutes after numerous attempts to dislodge the ship under its own power, Captain Hazelwood radioed the Coast Guard informing them of the grounding. For more than 45 minutes after the grounding, the captain attempted to maneuver free of the reef despite being informed by First Mate James Kunkel that the vessel was not structurally sound without the reef supporting it.

thumb|right|During the first few days of the spill, heavy sheens of oil covered large areas of the surface of Prince William Sound.

thumb|right|Beginning three days after the vessel grounded, a storm pushed large quantities of fresh oil onto the rocky shores of many of the beaches in the [[Knight Island (Alaska)|Knight Island chain. In this photograph, pooled black oil is shown stranded in the rocks]]

Multiple factors have been identified as contributing to the incident:

  • Exxon Shipping Company failed to supervise the master (ship's captain) and provide a rested and sufficient crew for Exxon Valdez. The NTSB found this practice was widespread throughout the industry, prompting a safety recommendation to Exxon and to the industry.
  • Exxon Shipping Company failed to properly maintain the Raytheon Collision Avoidance System (RAYCAS) radar, which, if functional, would have indicated to the third mate an impending collision with the Bligh Reef by detecting the radar reflector placed on the next rock inland from Bligh Reef for the purpose of keeping ships on course. This cause was brought forward by Greg Palast and is not presented in the official accident report.

Journalist Greg Palast stated in 2008: