Exxon Valdez oil spill a number of recommendations, such as changes to the work patterns of Exxon crew in order to address the causes of the accident. In response to the spill, the United States Congress passed the Oil Pollution Act of 1990 (OPA). The legislation included a clause that prohibits any vessel that, after March 22, 1989, has caused an oil spill of more than in any marine area, from operating in Prince William Sound. In April 1998, the company argued in a legal action against the Federal government that the ship should be allowed back into Alaskan waters. Exxon claimed OPA was
Oil tanker tonnage. The world's total oil tankers deadweight tonnage has increased from in 1970 to in 2005. The combined deadweight tonnage of oil tankers and bulk carriers, represents 72.9% of the world's fleet. In 2005, 2.42 billion metric tons of oil were shipped by tanker. 76.7% of this was crude oil, and the rest consisted of refined petroleum products. This amounted to 34.1% of all seaborne trade for the year. Combining the amount carried with the distance it was carried, oil tankers moved 11,705 billion metric-ton-miles of oil in 2005. By comparison, in 1970 1.44 billion metric tons of oil were