(CNN) -- More than three weeks after plugging its ruptured oil well with cement and mud from above, BP plans to start a procedure Monday that will pave the way for a permanent fix for the well.
Crews will start work Monday removing the capping stack that began trapping oil in the well last month, retired Adm. Thad Allen told reporters.
That will allow them to detach the blowout preventer and replace it with a new one -- key steps before engineers use a relief well to permanently kill the well 18,000 feet below the Gulf's surface.
"We will attempt to pull it free, and we are prepared to apply up to 80,000 [pounds] of force in addition to the weight of the blowout preventer to lift it," said Allen, the man charged with the government response to the oil disaster. "We call this the gentle tug".
After the relief well intercepts the well, it will take another few days to permanently seal the well with mud and cement from below in what's called a "bottom kill" procedure. CNN
