Robot Submarines Deployed to Contain Gulf Oil Spill

Crews have been using a robot submarine to try to stop an oil leak nearly a mile below the surface of the Gulf of Mexico, but officials said late yesterday it would take at least another day before they knew whether the job was completed.

It could take hours or it could take months to stop the 42,000-gallon-a-day oil leak at the site of the sunken oil rig off the Louisiana coast. For the second consecutive day, high waves prevented boats and equipment from going out to clean the spill. Airplanes sprayed chemicals to break up the oil.

Crews are using robot submarines to activate valves at the well head in hopes of cutting off the leak, which threatens the Gulf Coast's fragile ecosystem of shrimp, fish, birds and coral. If the effort fails, they'll have to start drilling again.

Officials said they were trying to stop the flow by using robot submarines to activate valves at the well head, but that would take 24 to 36 hours to complete. If that doesn't work, crews are also planning to drill a relief well to cut off the flow -- which could take several months.