Deepwater Horizon Oil Spill Disaster
On the 20th of April, 2010 there was an explosion followed by fire on the Transocean’s drilling oil rig, Deepwater Horizon operating in the Gulf of Mexico, in which 11 men died.
The cause of the explosion was a ‘blowout’; this is a build-up of pressure in the reservoir which literally blew gas and oil up through the risers onto the deck of the rig where it exploded and set fire to the rig.
There are measures and equipment put in place at the wellhead to prevent this occurrence, namely the blow out preventer (BOP). This component can be as tall as 60' and weigh 450 tons.
Although it has a selection of integrated so called ‘fail safe’ components, the BOP failed to operate and prevent the disaster.
The drilling rig sank on the 22nd of April, and from the bottom of the sea, 5000 feet below the surface, an oil plume poured crude oil unimpeded into the waters of the Gulf of Mexico.
Evacuation of survivors and search for the missing crew members were put in place, and then measures were taken to stop the flow of oil from the reservoir wellhead. The BOP was still in place and divers along with Remote Operated Vehicles (ROV’s) tried unsuccessfully to operate the annular and hydraulic ram mechanisms which would temporally stop the flow of oil but again these components refused to operate.
Meanwhile an unprecedented oil spill cleanup had commenced that included most of the equipment and methods discussed earlier, the Whale skimming ship being the world’s largest of its kind, scooping up and processing the floating oil. Many smaller skimmer ships belonging to the coastguards were also employed some of these using long booms to skim off the oil then set it on fire, chemical dispersants were also used; these would break the oil slick to droplets that the natural seawater bacteria would decompose.
Ashore volunteers were collecting seabirds and wildlife, taking them to temporary sanctuaries to be de-oiled, fed and cared for until they were safe to be released.
Many thousands of workers were laid-off due to the oil pollution, such as oyster farmers and shrimp harvesters along with those in the tourism industry.
All of these activities add to the cost of the oil spill cleanup; these costs along with the costs of major oil spill cleanups over the last decade are illustrated in a table in the Image section. From this table we can calculate the average costs of oil spill clean ups.
Average costs of the oil spill clean-up for the oil disasters listed in the table work out at $161 Million, this does not include the estimated costs of $12.5 Billion to clean up the Gulf of Mexico, as this is unprecedented and would give a false value.
1. timesonline - Deepwater Horizon Disaster.
2. guardianuk - Deepwater Horizon Disaster diary.