BP PLC closed the books on a defining week in an epic battle to defeat its ruptured oil well, with exhausted engineers forcing the surging crude underground with a torrent of mud and cement, preparing to make a final push to plug it from the bottom.
More than three months after the Deepwater Horizon rig exploded and triggered one of the world's worst oil spills, authorities weighed how to gather evidence from the mile-deep waters to help investigators determine what happened — and who could be at fault.
Even retired Coast Guard Adm. Thad Allen, who was brought in by the government to oversee the spill response amid poorly received efforts by the British petroleum giant, began looking ahead to a day when he could hang up his hat.
He told The Associated Press in an interview Friday that although he's still signed up "for the foreseeable future," he's had preliminary discussions with Homeland Security Secretary Janet Napolitano about what's next for him.
"I'll be the national incident commander until they don't have one anymore," he said, reflecting on the frenetic pace he's kept in the past few weeks not only by monitoring containment and cleanup progress, but keeping the media and the public updated.
"You have to pace yourself," he said. "You have to know when you can rest, take a nap. I try to achieve an economy of effort. It's obviously a fast pace and there are some long hours."
There was heartening news from other quarters, too, as scientists released a report saying that only about one-quarter of the nearly 207 million gallons of oil that leaked into the Gulf of Mexico is still oozing around the sea. Even the amount left, though, would still rank among the nation's worst spills.
BP left open the possibility that it could someday drill a new path into the same undersea reservoir of oil, still believed to hold nearly $4 billion worth of crude. Chief Operating Officer Doug Suttles said that BP hadn't considered the option yet but that "we're going to have to think about what to do with that at some point."
The prospect didn't sit well with Gulf Coast residents and officials.
"We can't trust 'em," said Billy Nungesser, president of Plaquemines Parish in coastal Louisiana, adding that federal authorities should assign special overseers to track BP every step of the way.
"We can't trust them to clean it up, we can't trust them to dig a new well," he said. "There's a lot of mistrust. We don't have any confidence in BP."
The Interior Department cautioned that the blown-out well, a relief well and a backup being drilled to help stop the leak would not themselves be used to pump new oil out of the reservoir.
"The well is almost dead. Under no circumstances are we going to allow them to reopen the well to extract oil and gas," spokeswoman Kendra Barkoff said.
With the crisis appearing to wind down, BP shuffled its leadership. Suttles, who spent more than three months managing the company's response to the spill, is returning to his regular job in Houston. Mike Utsler, a company vice president, will replace him.
The frenzied week started with BP preparing for the so-called "static kill," the company's most successful attempt yet to kill the blown-out well for good. Crews started pumping mud down the throat of the well on Tuesday, and by Friday engineers were waiting for cement sealing the oil in its underground reservoir to harden.
Now government officials and BP executives are focusing on the next step: Completing an 18,000-foot relief well that would be used to plug the bottom of the blowout with mud and cement. Crews could resume digging the final 100 feet of the well by Sunday, and it's expected to be completed between Aug. 13 to 15, said Kent Wells, BP's senior vice president.
Contributing to this report were Associated Press writers Jason Dearen and Jeffrey Collins in New Orleans.
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