BP Plc resumed work on a relief well in the Gulf of Mexico to permanently seal the source of the biggest offshore accidental oil spill in history.
The Macondo well, which spewed an estimated 4.9 million barrels of crude after an April 20 explosion aboard the Deepwater Horizon drilling rig, was plugged with mud and cement from the top in a process called static kill earlier this week.
“We know the static kill was a success, because when they pumped the mud in there, the pressure effectively went down to zero,” Robert MacKenzie, an analyst at FBR Capital Markets & Co., said by phone from Arlington, Virginia, yesterday. “The only reason they’re still drilling the relief well is because the government has asked.”
BP, based in London, tested the cement inserted into the top of Macondo and is encouraged by early data readings, Senior Vice President Kent Wells said during a conference call with reporters yesterday. The relief-well injection would assure the Macondo well never leaks again, Wells said.
The company capped the gusher with a stack of valves on July 15. BP has stopped skimming for oil in the open ocean because it’s having trouble finding crude on the surface, Doug Suttles, chief operating officer for exploration and production, said.
BP rose 1.95 pence to 425.35 pence in London trading yesterday. The shares are down 35 percent since the April explosion, which killed 11 workers.
The relief well, which has about 85 feet (26 meters) to go, will probably intercept Macondo between Aug. 13 and Aug. 15, Wells said. The company will resume drilling on Sunday night after pausing for a ranging test needed to determine if the well is going in the right direction.
After pumping mud and cement to Macondo from the bottom via the relief well, BP will remove the blowout preventer, which will later be used in investigations about the cause of the blast, Wells said.
The timing of the completion of the relief well will depend on the weather, as a tropical storm could delay drilling operations, BP said. Tropical Storm Colin approached Bermuda yesterday, on a course to pass north to Canada and avoid the spill site.
BP hasn’t decided what to do with the remaining oil and natural gas in the reservoir, Suttles said yesterday. The company could abandon the field or sell its stake, he said.
“Clearly, there’s lots of oil and gas here, and we’ll have to think about what to do with that,” he said during a press conference in New Orleans.
Neither the original wellbore nor the relief wells will be used as part of a future development, BP said in a subsequent e- mailed statement. The future use of the reservoir is not currently under consideration, the company said.
U.S. regulators would have to approve any future development of the reservoir.
The reservoir may have held 50 million to 100 million barrels of oil, BP Chief Executive Officer Tony Hayward said in a May 6 interview with the Houston Chronicle.