Although Allen described the debris as "not a huge problem," removing the sediment will take 24 to 36 hours. This will push a procedure known as "static kill" back to Tuesday. The operation was supposed to be implemented late Sunday or early Monday.
The static kill involves pumping mud, and possibly cement, into the blown-out well through the temporary cap that has kept it from leaking for more than two weeks.
Then comes the so-called bottom kill, in which cement pumped in from below the leak using the relief well will plug the gusher for good. The better the static kill works, the less time it will take to complete the bottom kill.
The blown-out well could be killed for good by late August, though a tropical storm could set the timetable back.
After an April 20 rig explosion that killed 11 workers, BP's blown-out well gushed an estimated 94 million to 184 million gallons of oil before the temporary cap stopped it July 15.
- There are signs that the era of thousands of oil-skimming boats and hazmat-suited beach crews is giving way to long-term efforts to clean up, compensate people for their losses and understand the damage wrought. Local fishermen are doubtful, however, and say oil remains a bigger problem than BP and the federal government are letting on.
- BP's new CEO is already coming under fire over the cleanup effort in the Gulf of Mexico. Bob Dudley has announced that BP will greatly scale back the oil cleanup effort, laying off 16,000 workers. This announcement comes despite some reports oil is still showing up along the coast.
- Meantime, the U.S. House response to the BP oil spill includes a call for an easing of the ongoing moratorium on drilling.
- Analysts said BP's estimate of spill costs was on the conservative side. Oppenheimer & Co. analyst Fadel Gheit predicts BP will eventually pay between $30 billion and $60 billion.
- Based on the upper estimate of oil spilled so far, BP could be fined up to $4.8 billion under the Clean Water Act, or up to $18.8 billion if it is found to have committed gross negligence or willful misconduct. BP's estimate assumes it would not get the harsher penalties.
The Associated Press contributed to this report.