On April 20th, 2010, the oilrig Deepwater Horizon caught fire and exploded, killing 11 of the 126 crew onboard. At this time, the cause of the explosion is still under investigation, though it is suspected it was caused by a natural gas blowout and the failure of an unprecedented number of safety systems. Deepwater Horizon was under lease to BP plc, and owned and operated by Transocean, the world’s largest offshore drilling contractor.
Since the fire, the undersea wellhead has been leaking at least 5,000 barrels of oil a day. Some estimates, based on the size of the undersea plume of oil, have the leak at up to 70,000 barrels of oil a day.
The first attempt to close off the leak using a cofferdam failed, but the second, using a length of tube inserted into the broken pipe on the seafloor, was at least partially successful. The siphon is able to catch somewhere between 1,300 and 3,000 barrels of oil per day, and is averaging around 2,000. This still leaves between 1,000 and 3,800 barrels to escape into the water of the Gulf.
At the moment, BP is setting up to attempt a top kill. A top kill involves using heavy drilling fluids and cement to plug the leak. Not only is there no guarantee it will work in this situation, it is also very risky. Should it misfire, the blowout preventer could spring a new leak if there’s a weak spot.
As a long-term solution, BP is still drilling two relief wells, but it is expected to take up to 3 months to get those ready to plug the well.
In the meantime, BP has been taken to task by the United States Environmental Protection Agency (EPA) for its continued use of Corexit, an oil dispersant that has been banned in the UK for the past decade. The EPA has demanded BP stop using Corexit, and switch to something less toxic. BP maintains that the dispersant is effective and environmentally safe, and also that nothing else is available in the quantities demanded by this spill.
Oil has washed ashore over about 100 km of the Gulf Coast, and officials say less than half can be cleaned up quickly. If the heavy oil gets into the wetlands, the options are to try and burn it off, flood it out, or leave it, and let natural processes degrade it. Unfortunately, all of these solutions will cause significant damage to the wetlands, which are the nurseries for shrimp, crabs, and shellfish, the heart of the Gulf fisheries.
The government of Louisiana is seeking permission from the Army Corps of Engineers to create a network of sand berms to link the barrier islands along the coast in the hope of protecting the fragile shoreline.
Further along in the Gulf of Mexico, the Loop, a current of warm water that eventually becomes the Gulf Stream, has shifted position, and remains uncontaminated by the massive slick, which is currently at least 6,500 km2 in size, but fluctuates daily.
At this moment, petroleum is still necessary for the proper function of our economy. However, disasters like the Deepwater Horizon oil spill must give us pause, and lead us to demand new, cleaner energy solutions from our governments and from the corporations we support with our dollars, euros, rubles, and dinars.