Millions of gallons of oil have leaked into the Gulf of Mexico from a blown-out well at the site of the Deepwater Horizon, which exploded on April 20 and sank two days later.
Coast Guard Adm. Thad Allen said Tuesday that BP is in the middle of its first major pipe cut in the company's latest bid to contain the oil spewing into the Gulf of Mexico.
Allen, the national incident commander, said it could be as many as three days before oil can be contained and siphoned to the surface. BP has another major cut to do before a cap can be lowered on to the leak.
It's the company's latest attempt to contain the leak. The effort to plug the spill failed over the weekend and the best chance to stop the gusher is now at least two months away.
Robot submarines carried equipment and cut small pipes at the bottom of the Gulf of Mexico on Monday to prepare to place a new containment valve over the blown-out well this week, while BP crews began working on yet another containment plan that could be added after the cut-and-cap effort.
The giant British oil company could begin cutting through the riser that's spewing oil and gas into the Gulf as soon as Wednesday, after which they will attempt to place the cap-like containment device that would siphon the mixture to the surface.
In a new plan announced Monday, BP said that after it places the containment valve over the leaking riser, it plans to connect a pipe to a separate opening on the blowout preventer at the blown-out well to suck oil to the surface. The opening is the same one they used to inject mud during the failed top kill procedure over the weekend, and the new effort will re-use some of the machinery left on the ocean floor.
BP said in a news release that the new maneuver would supplement the cut-and-cap procedure and help keep more oil from leaking into the gulf. That mission could start in mid-June.
In another step announced Monday, BP said it was also working on building a sturdier, free-standing pipe to carry oil from its containment efforts toward the surface. This new free-standing pipe would end about 300 feet (90 meters) below the surface, and a flexible hose would carry the oil the rest of the way to a surface ship. It's intended to give BP a way to disconnect its containment pipes in the event of a hurricane, and reconnect them after a storm.
BP said the construction of the free-standing riser, which crews could begin in late June or early July, would provide a "more permanent" way to capture the oil and gas as crews work to finish a pair of relief wells expected to plug the gusher for good. The first of the wells isn't expected to be completed before August.
BP didn't return calls seeking further comment on the new plans.
The company has repeatedly failed to stop the leak, which has gushed millions of gallons (liters) of oil into the Gulf of Mexico since an oil rig exploded on April 20, killing 11. The most ambitious attempt, called the "top kill," involved trying to force heavy-mud down the well and then seal it with cement. But BP engineers were forced to call it off Saturday when it failed to suppress the oil and gas oozing to the surface.
In this week's operation, BP engineers plan to cut the pipe leaking at the wellhead with a diamond-edged saw and then place a cap-like containment valve over the well. If successful, the company said it could siphon a majority of the gushing oil to the surface.
Video feeds throughout the day Monday showed the robots using a circular saw-like device to cut small pipes around the leaking riser, clearing the way for the operation which could begin as soon as Wednesday. BP spokesman Graham MacEwen said the robots were working to clear the way before they cut into the riser.
The Associated Press contributed to this report.