Ixtoc I was an exploratory oil well in the Bay of Campeche of the Gulf of Mexico, about 100 km (62 mi) northwest of Ciudad del Carmen, Campeche in waters 50 m (160 ft) deep. On
3 June 1979, the well suffered a blowout and is recognized as the second largest oil spill and the largest accidental spill in history.
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In the next nine months, experts and divers (including Red Adair) were brought in to contain and cap the oil well. Approximately an average of
ten thousand to thirty thousand barrels per day were discharged into the Gulf until it was finally capped on
23 March 1980. Prevailing currents carried the oil towards the Texas coastline. The US government had two months to prepare booms to protect major inlets. Eventually, in the US, 162 miles (261 km) of beaches and 1421 birds were affected by 3,000,000 barrels (480,000 m
3) of oil.
http://en.wikipedia.org/wiki/Ixtoc_I