BP is expected to announce within two days whether its top-kill procedure to plug the leak on the seabed has been a success
The chief executive of BP PLC says it will be about 48 hours before they know if pumping heavy mud into a blown-out well is successful in stopping the massive Gulf of Mexico oil spill.
CEO Tony Hayward said on the CBS "Early Show" that his confidence level in the well-plugging bid remains at about 60 to 70 percent.
THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.
ROBERT, La. (AP) — It could be late Friday or over the Memorial Day weekend before the world knows if BP's latest effort has succeeded in stopping the surge of oil in the Gulf of Mexico that has already surpassed the Exxon Valdez disaster as the biggest oil spill in U.S. history.
After an 18-hour delay Thursday to assess its efforts and bring in more materials, BP resumed pumping heavy drilling mud into the blown-out well 5,000 feet underwater in a procedure known as a top kill.
As the world waited, President Barack Obama announced major new restrictions on drilling projects, and the head of the federal agency that regulates the industry resigned under pressure, becoming the highest-ranking political casualty of the crisis so far.
In another troubling discovery, marine scientists said they have spotted a huge new plume of what they believe to be oil deep beneath the Gulf, stretching 22 miles from the leaking wellhead northeast toward Mobile Bay, Ala. They fear it could have resulted from using chemicals a mile below the surface to break up the oil.
Obama was scheduled to attend a briefing Friday at the U.S. Coast Guard Station in Grand Isle, La., by Adm. Thad Allen, who is overseeing the response to the spill. It would be his second visit to the region since the disaster began.
At the White House on Thursday, Obama acknowledged that his administration could have done a better job dealing with the spill and that it misjudged the industry's ability to handle a worst-case scenario.
"I take responsibility. It is my job to make sure that everything is done to shut this down," Obama said at a news conference, where he announced a series of new restrictions on oil drilling projects.
BP PLC insisted the top kill was progressing as planned, though the company acknowledged drilling mud was escaping from the broken pipe along with the leaking crude.
"The fact that we had a bunch of mud going up the riser isn't ideal but it's not necessarily indicative of a problem," spokesman Tom Mueller said.
Early Thursday, officials said the process was going well, but later in the day they announced pumping had been suspended 16 hours earlier. BP did not characterize the suspension as a setback, and Eric Smith, associate director of the Tulane Energy Institute, said the move did not indicate the top kill had failed.
"The good news is that they pumped in up to 65 barrels a minute and the thing didn't blow apart," Smith said. "It's taken the most pressure it needs to see and it's held together."
The top kill is the latest in a string of attempts to stop the oil that has been spewing since the drilling rig Deepwater Horizon exploded April 20, killing 11 workers.
If the procedure works, BP will inject cement into the well to seal it permanently. If it doesn't, the company has a number of backup plans. Either way, crews will continue to drill two relief wells, considered the only surefire way to stop the leak.
A top kill has never been attempted before so deep underwater. BP Chief Operating Officer Doug Suttles said the company is also considering shooting small, dense rubber balls or assorted junk such as golf balls and rubber scraps to stop up a crippled five-story piece of equipment known as a blowout preventer to keep the mud from escaping.
The stakes were higher than ever as public frustration over the spill grew and a team of government scientists said the oil has been flowing at a rate 2 1/2 to five times higher than what BP and the Coast Guard previously estimated.
Two teams of scientists calculated the well has been spewing between 504,000 and more than a million gallons a day. Even using the most conservative estimate, that means about 18 million gallons have spilled so far. In the worst-case scenario, 39 million gallons have leaked.
That larger figure would be nearly four times the size of the Exxon Valdez disaster, in which a tanker ran aground in Alaska in 1989, spilling nearly 11 million gallons.
"Now we know the true scale of the monster we are fighting in the Gulf," said Jeremy Symons, vice president of the National Wildlife Federation. "BP has unleashed an unstoppable force of appalling proportions."
BP officials said the previous estimate of 210,000 gallons a day was based on the best data available at the time and that the company's response was not tied to the estimate.
"I don't believe at any time we have misled anybody on this," Suttles said.
The spill is not the biggest ever in the Gulf. In 1979, a drilling rig in Mexican waters — the Ixtoc I — blew up, releasing 140 million gallons of oil.
In Washington, Elizabeth Birnbaum stepped down as director of the Minerals Management Service, a job she had held since July. Her agency has been harshly criticized over lax oversight of drilling and cozy ties with industry.
An internal Interior Department report released earlier this week found that between 2000 and 2008, agency staff members accepted tickets to sports events, lunches and other gifts from oil and gas companies and used government computers to view pornography.
Polls show the public is souring on the administration's handling of the catastrophe, and Obama sought to assure Americans that the government is in control and deflect criticism that his administration has left BP in charge.
"My job right now is just to make sure everybody in the Gulf understands: This is what I wake up to in the morning, and this is what I go to bed at night thinking about. The spill," he said.
Obama said he would end the "scandalously close relationship" between regulators and the oil companies they oversee. He also extended a freeze on new deepwater oil drilling and canceled or delayed proposed lease sales in the waters off Alaska and Virginia and along the Gulf Coast.
Fishermen, hotel and restaurant owners, politicians and residents along the 100-mile stretch of Gulf coast affected by the spill are fed up with BP's failures to stop the spill. Thick oil is coating birds and delicate wetlands in Louisiana.
Charlotte Randolph, president of Louisiana's Lafourche Parish, one of the coastal parishes affected by the spill, said: "I mean, it's wearing on everybody in this coastal region. You see it in people's eyes. You see it. We need to stop the flow."
"Tourism is dead. Fishing is dead. We're dying a slow death," she added.
The Coast Guard approved portions of Louisiana's $350 million plan to ring its coastline with a wall of sand meant to keep out the oil.
BP's top official, who had previously said the environmental impact on Gulf of Mexico would be modest, upgraded his assessment Friday to an "environmental catastrophe."
Also Friday, engineers in the Gulf tried the "junk shot" method in an attempt to stop a massive oil leak in the Gulf of Mexico, BP's chief executive Tony Hayward said.
The procedure involved shooting debris such as shredded rubber tires, golf balls and similar objects into the blowout preventer in an attempt to clog it and stop the leak. The goal of the junk shot is to force-feed the preventer, the device that failed when the disaster unfolded, until it becomes so plugged that the oil stops flowing or slows to a relative trickle.
The company plans to resume its "top kill" method, pumping heavy mud into the leak, later Friday, he said.
President Obama is scheduled to visit Louisiana on Friday for the second time since an oil rig explosion sent a historic amount of oil gushing into the Gulf.
Obama's visit comes as his administration has been criticized for its response to the massive underwater gusher that is now estimated to be twice the size of the Exxon Valdez disaster.
"I take responsibility. It is my job to make sure that everything is done to shut this down," Obama said Thursday at a White House news conference. "That doesn't mean it's going to be easy. That doesn't mean it's going to happen right away or the way I'd like it to happen. That doesn't mean we aren't going to make mistakes."
The president even said his 11-year-old daughter, Malia, weighed in on the issue on Thursday.
"You know, when I woke up this morning and I'm shaving, and Malia knocks on my bathroom door and she peeks in her head and she says, 'Did you plug the hole yet, Daddy?'" he said.
BP attempted to cap the spill using the "top kill" method Thursday.
The "top kill" involves pumping heavy drilling fluid into the head of the leaking well at the sea floor. The manufactured fluid, known as drilling mud, is normally used as a lubricant and counterweight in drilling operations. Officials hope the drilling mud will stop the flow of oil. Cement then would be pumped in to seal the well.
"This whole operation is very, very dynamic," said Doug Suttles, the company's chief operating officer "When we did the initial pumping [Wednesday], we clearly impacted the flow of the well. We then stopped to monitor the well. Based on that we restarted again. We didn't think we were making enough progress after we restarted, so we stopped again."
The light-brown material that was seen spilling out of the well throughout Thursday was the previously pumped fluid from the top kill procedure mixed with oil, he said.
CNN.com Live: Underwater view of top kill procedure
"I probably should apologize to folks that we haven't been giving more data on that," Suttles said when asked why it took so long for BP to announce it had suspended the top kill. "It was nothing more than we are so focused on the operation itself."
Suttles said part of the problem is that too much of the muddy fluid is leaving the breach instead of going down the well.
"So what we need to do is adjust how we are doing the job so that we get more of the drilling mud to go down the well," Suttles said.
He said one solution would be to introduce solids -- known as "bridging material" or its variant "junk shot" -- into the mix.
Oil spill demystified: A glossary
The revelation that BP suspended the "top kill" effort for 16 hours before it was restarted late Thursday afternoon troubled some.
Neither Obama nor Coast Guard Adm. Thad Allen, who is leading the government's response to the oil spill, appeared to be aware of the break when they addressed reporters at separate news conferences Thursday.
A White House official told CNN that people inside the White House knew about the temporary halt in the "top kill," but it wasn't clear if Obama was aware of it.
Plaquemines Parish President Billy Nungesser, who has been critical of the federal response to the spill, said the delay in information from BP was "par for the course."
"We've been dealing with this from day one, and the information has not flowed on anything," he said.
Stopping the leak took on even more urgency after government scientists released spill estimates that far exceed the previous 5,000-barrel-a-day number given by BP.
The burst well is spewing oil at a rate of at least 12,000 to 19,000 barrels a day, U.S. Geological Survey Director Marcia McNutt told reporters Thursday, meaning 260,000 to 540,000 barrels had leaked as of 10 days ago -- larger than the 250,000 barrels spilled when the tanker Exxon Valdez ran aground in Alaska's Prince William Sound in 1989.
The spill erupted April 20, when the drilling platform Deepwater Horizon exploded and burned about 40 miles off Louisiana. The rig sank two days later, taking 11 of its crew of 125 with it.
The rush of oil has taken its toll on Louisiana's sensitive coastal marshes. Heavy oil has been killing plant life and fouling local wildlife and fisheries. On Thursday, the eve of the Memorial Day holiday weekend, the beaches of Grand Isle were empty.
"If only it gets stopped, if what they did yesterday works, that's the beginning of the end," Grand Isle Tourism Commissioner Josie Cheramie said. "We can clean up what's already been put out there, but we just really need to get it stopped. That's the main thing."
