BP today claimed "a significant milestone" in its efforts to plug a leaking well for good ahead of a US government report that will show most of the leaked crude is already gone.
The world's worst accidental marine oil spill has caused an environmental disaster and shaken the US presidency of Barack Obama. It has also wiped billions of dollars off the value of one of the world's largest oil companies and cost BP's chief executive, Tony Hayward, his job.
But heavy drilling mud pumped into the Gulf of Mexico well yesterday to stem the flow of crude is now controlling its pressure, BP said.
The next step in the so-called "static kill" operation is to pump in cement behind the mud as a seal, but BP said monitoring was required to see whether more mud should be pumped in first.
"The MC252 well appears to have reached a static condition - a significant milestone," it said in a statement.
Mr Hayward and his heir apparent, Bob Dudley, are due to visit Russia, home to a quarter of BP's output and a country Mr Dudley fled in 2008 after a dispute with joint venture partners there.
But their minds could be focused on events miles away as efforts to subdue for good the deepwater gusher that was temporarily capped in mid-July reach a climax.
In a preview of a government report on clean-up progress due out later today, Mr Obama's main energy adviser appeared to indicate that the scale of the remaining problem might not be as great as some have feared.
"The good news is that the vast majority of the oil appears to be gone," Carol Browner said on ABC's Good Morning America.
A New York Times story said the report would show three-quarters of the oil released has already evaporated, dispersed, been captured or eliminated.
The full magnitude of the spill, triggered in April by a deadly rig explosion at the BP-owned Macondo well, became apparent earlier this week as government scientists released revised figures showing almost 5 million barrels of oil leaked before the well was temporarily capped on July 15th.
This made it the world's largest accidental maritime release of oil, surpassing the 1979 Ixtoc well blowout in Mexico's Bay of Campeche that gushed almost 3 million barrels.
The spill has disrupted the livelihoods of fishermen and tourism operators and triggered a barrage of damages lawsuits against BP. The company has said it will pay all legitimate claims and clean up fouled beaches and marshes.
Reuters