BP: Upcoming kill attempt might do the trick alone

After insisting for months that a pair of costly relief wells were the only surefire way to kill the oil leak at the bottom of the Gulf of Mexico, BP officials said Monday they may be able to do it just with lines running from a ship to the blown-out well a mile below.

As crews planned testing to determine whether to proceed with a "static kill" to pump mud and perhaps cement down the throat of the well, BP Senior Vice President Kent Wells said if it's successful the relief wells may not be needed, after all, to do the same weeks later from the bottom.

The primary relief well, near completion, will still be finished and could be used simply to ensure the leak is plugged, Wells said.

"Even if we were to pump the cement from the top, we will still continue on with the relief well and confirm that the well is dead," he said. Either way, "we want to end up with cement in the bottom of the hole."

Before the effort can begin, engineers must probe the broken blowout preventer with an oil-like liquid to decide whether it can handle the static kill process. They had hoped to begin the hours-long test Monday but delayed it until Tuesday after a small leak was discovered in the hydraulic control system.

Government officials and company executives have long said the relief wells, which can cost about $100 million each, may be the only way to make certain the oil is contained to its vast undersea reservoir.

Meanwhile, a federal task force estimated that about 172 million gallons (about 650 million liters) of oil made it into the Gulf between April and mid-July, when a temporary cap bottled up all the oil. The earlier estimate had been as high as 184 million gallons (about 700 million liters).

The company began drilling the primary, 18,000-foot (5,500-meter) relief well May 2, 12 days after the Deepwater Horizon rig exploded and killed 11 workers, and a second backup well May 16. The first well is now only about 100 feet (30 meters) from the target, and Wells said it could reach it as early as Aug. 11.

"Precisely what the relief wells will do remains to be seen given what we learn from the static kill," BP spokesman Daren Beaudo said. "Can't predict it for certain."

Retired Adm. Thad Allen, the government's point man on the spill response, said Monday that the focus now is on making sure the static kill is successful. But he cautioned that federal officials don't see it as "the end all, be all until we get the relief well done."

The static kill is meant as a bit of insurance for the crews who have spent months fighting the oil spill. The only thing keeping oil from blowing into the Gulf at the moment is the experimental cap, which has held for more than two weeks but was never meant to be permanent.

BP and federal officials have managed to contain large parts of the spill through skimmers, oil-absorbant boom and chemical dispersants meant to break up the oil.

Federal regulators have come under fire from critics who say that BP was allowed to use excessive amounts of the dispersants, but government officials counter that they have helped dramatically cut the use of the chemicals since late May.

The Environmental Protection Agency released a study Monday concluding that when mixed with oil, chemical dispersants used to break up the crude in the Gulf are no more toxic to aquatic life than oil alone.