Key oil spill evidence raised to Gulf's surface

ON THE GULF OF MEXICO (AP) - Engineers have hoisted a key piece of evidence in the BP oil spill to the surface of the Gulf of Mexico, and investigators will soon get their first chance to scrutinize the equipment in person.

Investigators hope they will be able to determine why the device didn't stop the oil that leaked into the Gulf.

Engineers on Saturday used a crane attached to a semi-submersible drilling vessel to lift the 50-foot, 300-ton blowout preventer from a mile beneath the sea to the surface. It took nearly 30 hours to raise the blowout preventer.

A U.S. government evidence team is waiting to take possession of it.

The April 20 explosion aboard the Deepwater Horizon killed 11 workers and led to 206 million gallons of oil spewing from BP PLC's undersea well.

Investigators know the explosion was triggered by a bubble of methane gas that escaped from the well and shot up the drill column, expanding quickly as it burst through several seals and barriers before igniting.

But they don't know exactly how or why the gas escaped. And they don't know why the blowout preventer didn't seal the well pipe at the sea bottom after the eruption, as it was supposed to.

While the device didn't close - or may have closed partially - hearings have produced no clear picture of why it didn't plug the well.

Lawyers will be watching closely, as hundreds of lawsuits have been filed over the oil spill. Future liabilities faced by a number of corporations could be riding on what the analysis of the blowout preventer shows.

The raising of the blowout preventer followed Thursday's removal of a temporary cap that stopped oil from gushing into the Gulf in mid-July. No more oil was expected to leak into the sea, but crews were standing by with collection vessels just in case.