HOUSTON — BP began a maneuver known as a top kill on a stricken well in the Gulf of Mexico on Wednesday afternoon, generating hope that the company might soon be able to plug a leak that has poured millions of gallons of oil into the water and fouled 100 miles of Louisiana coastline.
BP officials emphasized that success was not guaranteed, and that the top kill could fail at any moment. But engineers and geologists following the effort, in which heavy fluids are injected into the well, said the likelihood of success grew with each passing hour.
“The operation is proceeding as we planned it,” said Tony Hayward, BP’s chief executive, in a statement Wednesday evening. “We will be continuing for at least another 24 hours.”
Doug Suttles, BP’s chief operating officer for exploration and production, said at a news conference Wednesday evening that it would be a day or more before it was clear whether the top kill had worked. “It’s too early to know if it’s going to be successful,” Mr. Suttles said.
He said that more than 7,000 barrels of drilling mud had been pumped at varying rates.
At the same news conference, Rear Admiral Mary E. Landry of the Coast Guard, the federal on-scene coordinator, said that she was encouraged but that she did not want to express optimism until the well was secured.
The outcome of the effort may become known about the time President Obama is scheduled to discuss new restrictions on offshore drilling at a news conference Thursday after receiving a report on drilling safety from Interior Secretary Ken Salazar.
Mr. Obama is expected to extend the informal moratorium that he declared after the BP spill began on new offshore drilling permits in the gulf and off the North Slope of Alaska until the cause of the accident is determined and stricter safety and environmental safeguards are in place.
Some fishermen hired by BP to mop up the gulf spill report nausea and breathing troubles after contact with oil and dispersant. A congressman calls for mobile health clinics to treat them.
ON BARATARIA BAY, LA. — In the Louisiana marsh, oil-coated pelicans flap their wings in a futile attempt to dry them. A shorebird repeatedly dunks its face in a puddle, unable to wash off. Lines of dead jellyfish float in the gulf, traces of oil visible in their clear “bells.”
These scenes, scientists say, are confirmation of what they had feared for a month. Now that oil from the Gulf of Mexico’s vast spill has come ashore — in some places, as thick as soft fudge — it is causing serious damage in one of the country’s great natural nurseries.