Crews hoisted the blowout preventer that once sat atop BP’s stricken well to the surface of the Gulf of Mexico on Saturday night, and the federal leader of the spill response said that there was no longer any risk that the well might leak again.
“This well does not constitute a threat to the Gulf of Mexico at this point,” the leader, Thad W. Allen, a former Coast Guard admiral, said during a conference call with reporters. “The well has been effectively secured regarding any potential source of pollution.”
On Friday night, BP technicians replaced the original damaged blowout preventer — the safety device that failed when the Deepwater Horizon drilling rig exploded on April 20 — with another one that will be better able to handle any pressure changes that might take place during the final steps in the process of plugging the well permanently. That procedure should occur this week, Admiral Allen said.
The original blowout preventer is a major piece of evidence in the investigation into what caused the rig explosion, which killed 11 workers and resulted in the largest maritime oil spill in American history. Federal officials said they took possession of the device after it reached the surface.
No appreciable amount of oil or gas has leaked from the well since July 15, when technicians closed valves on a tight-fitting cap that had been installed several days earlier. In early August, mud and cement were pumped into the well from the top, effectively sealing the bottom of the well from the oil reservoir below it.
But all along, BP and government officials have said that the process could not be completed until the completion of a relief well, through which drilling mud and cement will be pumped into the stricken well.
Admiral Allen said that with a new blowout preventer installed, crews will conduct diagnostic tests before drilling of the relief well resumes. The relief well was expected to intercept the stricken well about four days later.