On April 20, when the Deepwater Horizon Transocean-BP oil rig exploded, killing eleven workers and, two days later, sinking completely into the Gulf of Mexico, everyone knew that the damage was going to be immense—but no one knew it would be quite as far-spreading as it now appears. The Deepwater Horizon was an ultra-deepwater rig which, in September 2009, drilled the deepest oil well in history with a vertical depth of 35,050 and a measured depth of 35,055 feet (with just over 4,000 feet of the depth in water) in the Tiber oilfield. At the time of the explosion, the rig was located in the Mississippi Canyon area, forty miles offshore from Louisiana with an estimated water depth at 5,000 feet, just a few feet short of one mile. At the leak rate of 5,000 barrels (210,000 gallons) per day, the Deepwater Horizon spill is slated to become the worst environmental catastrophe in over a decade—perhaps surpassing even the Exxon-Valdez spill in 1989.
The magnitude of the spill is due to many factors, one of the main ones, of course, being the failure of BP—the company leasing the rig from Transocean—to successfully implement the emergency plans. The initial attempt to lower a gigantic containment dome known as a “cofferdam” on top of the largest leaking area on the seabed failed this weekend (it had never been attempted before at such depths), leaving BP rushing for a new plan. And each plan isn’t without its own industry slang.
Plan B for BP is known as the “top hat”—a containment box that will be placed over the smaller of the two leaks. The top hat would limit the amount of water exposed to the leak and thus, hopefully, bypass the dangerous formation of ice-like hydrates which clogged the containment dome’s pipes and made the dome buoyant. While the top hat isn’t the end-all-be-all solution for the spill, it would help to check the unfettered leak taking over the Gulf.
Another idea is called a “top kill” which involves shooting mud and concrete directly into the reconfigured blowout preventer—the device that failed during the April 22 explosion. If it works, the top kill will plug up the leak, preventing the oil from reaching the ocean, but it could take several weeks before it is effective.
One of the stranger solutions is the “junk shot” where tires and golf balls and shredded rope are literally shot into the blowout preventer to clog it. Like the top kill, however, BP would not be able to utilize the junk shot for two or three weeks, and, like all containment efforts, it has never been performed at such depths—the possible success of the junk shot is unknown.
Until the leak is completely capped, there is no way to know the damage that will occur to the Gulf coast. Already, tar balls, pieces of emulsified oil, have washed up on Dauphin Island, Alabama, and several birds have died due to the oil slick—not to mention the economic effect of the diminished fishing industry. For the moment we can only hope that one of the strangely coined secondary plans works.
Photo by Pan-African News Wire