HOUSTON, Sept 15 (Reuters) - BP Plc's ruptured Gulf of Mexico well that caused the biggest U.S. offshore oil spill ever could be killed for good within four days, the U.S. official overseeing the spill response said on Wednesday.
"Four days from now it can all be done," retired Coast Guard Admiral Thad Allen told reporters at a briefing in Kenner, Louisiana.
That will end the seabed chapter of the disaster that started with a blowout on April 20 that led to an explosion aboard the Deepwater Horizon drilling rig, killing 11 men. The well spewed more than 4 million barrels of oil into the sea.
Allen said a relief well should intercept BP's blown-out Macondo well within 24 hours, or by mid-morning Thursday.
Once intercepted, BP will pump mud and cement into the Macondo well near it's bottom, about 13,000 feet (4,000 metres) beneath the seabed.
After the cement cures, BP will conduct pressure tests that will show whether the well is indeed dead.
"It could be sooner, depending on when the intercept occurs," Allen said of the four-day timeline.
The relief well had been on hold for weeks until Monday, when drilling resumed after BP had conducted a series of other steps toward the final kill.
The company drilled 30 feet (9 metres), then stopped to use sensors on Tuesday to ensure the relief well was on the right track. Drilling on the last 20 feet (6 metres) began early on Wednesday, Allen said. (Reporting by Kristen Hays, editing by Vicki Allen)