If the undersea maneuver goes as planned, a tighter containment cap may be in place within a week.
In another subsea attempt to control its gushing well, BP began a risky procedure Saturday that could contain all of the oil spewing into the Gulf of Mexico within a week.
But the around-the-clock procedure comes with a price: Millions of gallons of oil will flow into the gulf for at least two days until a new cap is mounted. Although it’s the latest in a series of attempts to contain the gusher, it’s not a final fix.
By Saturday afternoon, robots had removed a containment cap from the leaking well, a move that caused oil to freely gush into the ocean. The well has been spewing as many as 60,000 barrels a day since late April.
“What I’d say at this point is, we’re on plan,” Kent Wells, a BP senior vice president, said Saturday evening.
In a series of delicate steps, a tighter cap will be placed over the gushing pipe. If all goes according to plan, as many as four ships could draw in between 60,000 and 80,000 barrels of oil a day.
The new cap would be installed within four to seven days during a window of calm seas, Wells said. The cap will be “fundamental to our ability to disconnect and reconnect during hurricanes,” he said.
“There’s a brief period here where we will have more flow,” he said.
While the work is being performed, as many as 8,000 barrels a day will be drawn in through several underwater collection lines and held in vessels including the Q4000, which has been capturing oil and gas since mid-June, said Mark Proegler, a BP spokesman.
The new system is not a permanent fix and is not guaranteed to work.
After removing the containment cap, the engineers turned to maneuvering the robots to unbolt a flange below the cap.
As of Saturday evening, crews were working on removing the first of six bolts using hydraulic horsepower, Wells said. He expects work on the bolt removal to last into Sunday night.
Once the top flange is removed, BP has to push together two sections of drill pipe that are in the well head. Then a flange transition spool will be lowered on top of the flange using a crane. After the spool is in place, the new cap can be positioned. The cap will allow new connections to collect oil and it also has valves that can control the flow of oil.
Proegler said it’s hard to assess which steps are riskier than others. On Saturday he said the imminent test was to properly remove the flange.
“The whole thing is challenging,” he said.
On Friday, Coast Guard Adm. Thad Allen said the new cap could be in place by Monday, which is still possible.
The cap replacement is the latest in a series of efforts BP has undertaken since the April 20 explosion to halt oil gushing from the well.
In early May, a large collection dome became clogged with gas hydrates. Weeks later, a so-called top kill effort to plug the well failed when the upward force of oil was too great to overcome.
If complications arise this time, Wells said, other options are available, including installing another containment cap.
“We do have some backups for backups,” he said.
Meanwhile, BP is in the final stages of setting up the Helix Producer, a vessel capable of holding up to 25,000 barrels of oil per day. Wells said the vessel could be in operation as early as today.
Proegler said BP began planning the cap operation a week after the explosion.
“It’s taken a long time to put this in place,” he said.
The ultimate solution, expected in mid-August, will be the completion of relief wells that intercept the failed well and provide a path to insert heavy mud and cement to plug it.