April 23 (Bloomberg) -- An oil spill near the site where Transocean Ltd.’s Deepwater Horizon rig caught fire April 20 and sank yesterday has spread over an area of 100 square miles in the Gulf of Mexico and is drifting northeast toward shore.
The spill measures 10 miles (16 kilometers) by 10 miles, about four times the area of Manhattan, and is comprised of a “light sheen with a few patches of thicker crude,” U.S. Coast Guard Lieutenant Commander Cheri Ben-Iesau said today. The Coast Guard’s search continues for 11 rig workers who are still missing, she said in a telephone interview.
Aircraft hired by BP Plc, the oil producer that leased the Deepwater Horizon from Transocean, sprayed the spill with a chemical dispersant overnight, Ben-Iesau said. Eleven skimming vessels were collecting oil from the water’s surface, she said. The oil spill is about 43 miles south of Venice, Louisiana.
“This certainly has the potential to be a major spill,” David Rainey, London-based BP’s vice president for Gulf of Mexico production, said yesterday at a press conference in New Orleans. An effort to close well valves on the sea floor using remote-operated vehicles will continue. BP hired a rig capable of drilling down to plug the well if necessary, he said.
Michael O’Berry, a senior chief petty officer with the Coast Guard, said remote-operated vehicles found no new leakage from the well yesterday.
The rig had burned for more than 24 hours after an explosion April 20 that Geneva-based Transocean said was caused by a so-called blowout, an unexpected surge in pressure that ejected petroleum at the top of the well.
Of 126 workers aboard, 115 were rescued. If the missing workers died, it would be the deadliest U.S. offshore rig explosion since 1968, when 11 died and 20 were injured at a platform owned by Gulf Oil Corp., according to data from the Minerals Management Service. A 1987 helicopter crash aboard a Forest Oil Corp. platform killed 14 people.
Royal Dutch Shell Plc shut its Nakika offshore oil platform and a pipeline in the Gulf of Mexico a mile away, as a precaution against the sunken Deepwater Horizon drifting into it and causing another spill, said Jill Davis, a company spokeswoman. Another, unidentified pipeline was shut nearby, the Coast Guard said.
The Coast Guard throttled back its search for survivors to the cutter Coho overnight, Ben-Iesau said. Three aerial searches are planned today. Hope was fading that the 11 missing crew survived, Coast Guard Rear Admiral Mary Landry said at yesterday’s press conference.
To contact the reporter on this story: Jim Polson in New York at firstname.lastname@example.org
To contact the editor responsible for this story: Susan Warren at email@example.com.