June 1, 2010 | 16
BP et al. have burned through more than five weeks and at least as many failed attempts to get control of the Mississippi Canyon 252 well spewing oil into the Gulf of Mexico. Now the arrival of hurricane season—officially June 1 to November 30—threatens to make the difficulties worse.
The National Oceanic and Atmospheric Administration is expecting a busy hurricane season, but says that this has nothing to do with the oil slicks developing in the Gulf. “The oil is not expected to appreciably affect either the intensity or the track of a fully developed tropical storm or hurricane,” according to a document NOAA posted to its Web site last week.
The real danger lies in the possibility that storm surges might carry oil into the coastline and inland or force boats aiding in the efforts to control the oil leak back to shore.
Even without the threat of a storm to disrupt delicate operations using remote-control submarines, BP was unable to achieve a “top kill” of its leaking well over the Memorial Day weekend. Despite pumping more than 30,000 barrels of heavy mud into the damaged well, BP could not overcome the flow of oil racing from the well.
The company announced Tuesday it’s moving forward with plans to use robotic subs and diamond-toothed saws to cut through and separate the well’s damaged riser pipe from a different pipe atop the blowout preventer. The riser pipe used to lead up to the Deepwater Horizon rig but was mangled when it sank. Once the riser pipe is severed, the company plans to install a cap that it hopes will capture most of the oil and gas flowing from the well and transport the crude to a drill ship on the surface.
BP’s latest plan comes with the familiar list of caveats—including a reminder that they are attempting to perform a delicate task using robots located under 15,00 meters of water, and that such a containment cap has never before been deployed at that depth and under the current conditions.
And things would get worse before they got better: if the riser pipe is cut, oil spillage will increase 20 percent until the cap can be put in place, which could take as long as three days, Admiral Thad Allen, National Incident Commander for Deepwater BP oil spill response, said Tuesday during a press briefing. Given the number of failed efforts to shut off the flow of oil into the Gulf, Allen pointed out that the mission has gone from trying to cap the damaged well to containing the flow of oil until a relief well can be used to tap into the main well and alleviate some of the pressure forcing the oil out of the seabed. The goal is to collect as much of the oil and gas spewing from the well as possible and even bring in a rig platform that could be used to refine the oil collected.
Two relief wells are currently being drilled to tap into the leaking well and alleviate much of the pressure forcing out the oil. The first well, started a month ago and not expected to be finished for another two months, is currently more than 3,600 meters below the Gulf’s surface but needs to go another 1,800 meters. The Deepwater Horizon Incident Joint Information Center claims that the well, being drilled at an angle of 35 degrees, is 10 days ahead of schedule. A second relief well was started on May 16 and has reached a depth of more than 8,500 feet.
Although the consensus among BP, the Coast Guard and a number of researchers appears to be that a relief well will help workers get control of the spill and even shut it down, the procedure is far from easy. The idea behind a relief well is to drill diagonally into the seabed to the side of the main well with the hope of tapping into the broken well and channeling some of the oil flow out to the relief well. Allen noted that, although a relief well would likely help the situation, it will not be easy intercepting the original well several thousand feet below the seabed.
Now imagine trying to do that with swelling waves and high winds.
Images courtesy of BP