Ixtoc I oil spill was one of the largest oil spills in history. It took place in the Bay of Campeche, a part of the Gulf of Mexico, in 1979 and 1980. The spill released about 140 million gallons (530 million liters) of oil—more than any previous oil spill.
Ixtoc I was an exploratory oil well about 50 miles (80 kilometers) off Mexico’s coast. On June 3, 1979, a blowout at the well released oil and gas that caused a fire and explosion. All 63 workers on the drilling rig were evacuated safely. The badly damaged rig was towed away from the well site and scuttled (made to sink). However, petroleum gases continued to rise to the ocean surface and burn for about 290 days. Workers eventually drilled two relief wells that reduced the flow of oil, then pumped mud into the relief wells to stop the flow completely. The well was finally capped on March 23, 1980.
About half of the released oil evaporated into the atmosphere. About one-fourth sank to the bottom of the ocean. Most of the rest was recovered mechanically or was broken down through microbial degradation and other weathering processes. Microbial degradation is the breaking down of the oil by tiny organisms. Weathering involves changes to the oil’s chemical and physical properties after exposure to the environment.
Some of the oil that spread from the spill site washed ashore on beaches in Mexico and Texas. The oil in sandy beach areas was easier to clean up than the oil that polluted wetlands or mangrove forests. Remains of oil that sank to the ocean floor still could be found buried in the sand more than 30 years later.
The Ixtoc I oil spill had a significant impact on birds, fish, shrimp, squid, and other organisms. However, the ecosystems showed great resiliency. The populations of many of the affected organisms returned to their previous numbers within two to three years. The oil spill threatened to contaminate one of the few known nesting places of the endangered Kemp’s ridley turtle. In response, scientists airlifted thousands of Kemp’s ridley hatchlings to oil-free water.
When the Ixtoc I spill occurred, it was the largest marine oil spill in history. Since that time, there have been even greater spills. In 1991, for instance, the Iraqi government purposely dumped more than 200 million gallons (760 million liters) of crude oil into the Persian Gulf. Another major spill took place in the Gulf of Mexico in 2010. That spill released about 200 million gallons (760 million liters).
See also Oil spill .
