NEW ORLEANS – Now that BP appears to have vanquished its ruptured well, authorities are turning their attention to gathering evidence from what could amount to a crime
scene at the bottom of the sea.

The wreckage — including the failed blowout preventer and the blackened, twisted remnants of the drilling platform that exploded, burned and sank in mile-deep water in the Gulf in April — may
be Exhibit A in the effort to establish who is responsible for the
biggest peacetime oil spill in history.

Hundreds of investigators can't wait to get their hands on evidence. The FBI is conducting a criminal investigation, the Coast Guard is seeking the cause of the blast, and lawyers are pursuing
millions of dollars in damages for the families of the 11 workers
killed, the dozens injured and the thousands whose livelihoods have been
damaged.

"The items at the bottom of the sea are a big deal for everybody," said Stephen Herman, a New Orleans lawyer for injured rig workers and others.

BP will almost certainly want a look at the items, particularly if it tries to shift responsibility for the disaster onto other companies, such as Transocean, which owned the oil platform,
Haliburton, which supplied the crew that was cementing the well, and
Cameron International, maker of the blowout preventer.

BP and Transocean — which could face heavy penalties if found to be at fault — have said they will raise some of the wreckage if it can be done without doing more damage to the oil well. That would
give the two companies responsibility for gathering up the very
evidence that could be used against them.

But the federal government has said it simply doesn't have the know-how and the deep-sea equipment available to the drilling industry. And it said the operation will be closely supervised by the
Coast Guard.

The crisis in the Gulf appeared to be drawing to a close this week when BP plugged up the top of the blown-out well with mud and then sealed it with cement. Next, the company plans to use a
relief well extending more than two miles below the sea floor to inject
mud and cement just above the source of the oil, thereby sealing off the
well from the bottom, too.

In other developments Friday, BP said it might drill again someday into the same lucrative undersea reservoir of oil, which is still believed to hold nearly $4 billion worth of crude. That
prospect is unlikely to sit well with Gulf Coast residents furious at the oil giant.

"There's lots of oil and gas here," Chief Operating Officer Doug Suttles said. "We're going to have to think about what to do with that at some point."

Also Friday, BP said Suttles — who has spent more than three months managing BP's response efforts on the Gulf — is returning to his day job in Houston. Mike Utsler, a vice president who
has been running BP's command post in Houma, La., since April, will
replace him.

Willie Davis, a 41-year-old harbormaster in Pass Christian, Miss., said he fears his area will be forgotten if BP pulls out too soon. "I'm losing trust in the whole system," he said. "If they
don't get up off their behinds and do something now, it's going to be
years before we're back whole again."

Utsler told Gulf residents not to worry, saying the spill's effects are "a challenge that we continue to recognize with more than 20,000-plus people continuing to work."

Investigations of the disaster began immediately after the rig blew up on April 20. The government alone is conducting about a dozen, including several congressional investigations, criminal
and civil probes by the Justice Department, and an examination by an
expert panel convened by President Barack Obama.

Officials want to find out not only the cause of the explosion, but also how oil drilling a mile or more below the surface can be made safer.

A final outcome could be years away, particularly if someone is charged with a crime, said David Uhlmann, former chief of the Justice Department's environmental crimes team.

"Normally an investigation of a case this complicated would take two to three years. This is not a normal case," he said. "This is the worst environmental disaster in U.S. history."

Any items brought up from the seafloor will be photographed and preserved. Investigators for the government, BP and others who have a stake in the case will try to come up with testing
procedures acceptable to all sides.

The blowout preventer will probably make it to the surface. The 300-ton mechanism is designed to be placed on a well and brought back to the
surface for reuse. It was supposed to be the final line of defense
against a catastrophic spill, but BP documents obtained by a
congressional committee showed the device had a significant hydraulic
leak and a dead or low battery.

"That piece of equipment will tell us whether the blowout preventer had a design defect or whether it was mechanical or human error that caused
this disaster," Herman said.

Brent Coon, an attorney for one of the thousands of plaintiffs seeking damages, said the rig might contain "black boxes" that recorded critical
data and control panels that could be removed to re-create conditions
before the explosion.

Transocean has asked the government for permission to test the blowout preventer and hopes to see it raised it in September, company President
Steven Newman said.

Getting to the exploded rig itself might be harder. It would be impractical to raise the entire structure because of its immensity,
twice the size of a football field, Coast Guard Rear Adm. Paul Zukunft
said. He would not say whether it would be possible to cut off vital
pieces of the structure.