BP Plc removed a failed blowout preventer from atop its ruptured Gulf of Mexico oil well on Friday afternoon, a company spokesman said.
The Deepwater Horizon BOP stack was successfully detached from the Macondo well shortly after 1 p.m. CDT (7 p.m. British time), spokesman Daren Beaudo said.
There is no oil coming from it, he said of the well.
One of several live feeds of the procedure from underwater robots showed a cloudy brown substance coming from the well. Beaudo said the trailing brownish material was residual drilling mud pumped into the well in earlier operations.
A blowout preventer is intended to shut off a well if oil or gas uncontrollably rushes to the top. It failed to do so in the case of the Macondo well.
BP will replace the 50-foot (15-m) stack of valves and pipes with a working blowout preventer and then resume drilling a relief well to plug the leak for good, the company said.
Retired Coast Guard Admiral Thad Allen, the top U.S. official overseeing the spill response, said officials are monitoring the slow lifting process.
We will continue to closely monitor progress as the BOP, which along with the latching device weighs approximately 1 million pounds, is lifted to the surface in the next 24-36 hours, Allen said in a statement.
The company said earlier on Friday that, weather permitting, BP expects the relief well to intersect the Macondo well near its bottom about 13,000 feet (4,000 m) beneath the seabed in mid-September.
BP will then pump mud and cement into the well to ensure the leak is dead, the company said.
BP and government officials did not expect oil to leak from the well once the failed blowout preventer was lifted off. The company pumped cement into the well from the top on August 5, which officials believe sealed off the well from the reservoir.
The failed blowout preventer is critical evidence in various investigations into the April 20 blowout that led to an explosion aboard the Deepwater Horizon drilling rig and killed 11 men.
Officials removed it before finishing the relief well to preserve its value as evidence and ensure a working blowout preventer was on the well to handle any pressure increases when drilling resumes.
(Editing by Cynthia Osterman)