13 March 1991: Exxon fined $1bn for oil spill

In 1967 a major oil field was discovered at Prudhoe Bay in the north of Alaska. Production began in 1977 and by the late 1980s output from this and other Alaskan fields accounted for a quarter of total US production.

To transport the oil from the far north, the trans-Alaska pipeline was built, running 800 miles from Prudhoe Bay to the town of Valdez, the nearest ice-free port. At Valdez, oil was loaded into tanker ships to be transported further south.

On 24 March 1989, the tanker Exxon Valdez ran aground on a reef. A number of factors have been blamed for the accident, including crew fatigue, outdated and malfunctioning navigation equipment, and allegations that the captain was drunk. Whatever the cause, the ship’s hull was breeched, sending at least 11 million US gallons of oil into the sea and onto nearby beaches.

The result was one of the worst environmental disasters in maritime history. Large numbers of fish and birds died, with devastating knock-on effects onthe Alaskan fishing industry. The US government took action against Exxon for breeching laws against pollution and to recover clean-up costs. On 13 March 1991, Exxon agreed to pay up to $1bn to regulators and the state of Alaska.

This wasn’t the end of Exxon’s liability. In 2008, it was ordered to pay civil compensation and $507.5m in damages to Alaskan fisherman and fishing firms (reduced from an initial award of $5bn). Delayed interest payments effectively doubled this bill. Experts estimate that the overall costs to the energy giant, including emergency payments and money the company spent on its own clean-up efforts, totalled $3.8bn.