After pumping heavy drilling mud for eight hours, BP pronounced early
Wednesday that it had finally brought its blown-out oil well at the
bottom of the
The company and the Obama administration cautioned
that it would take another step — completion of a relief well later
this month — to officially pronounce the monstrous gusher dead, but the
apparently successful “hydrostatic kill” operation drove one huge nail
in the coffin.
BP began the process — which injects a dense
“drilling mud” that tips the scales at 13.2 pounds per gallon to muscle
oil and gas back down its ancient reservoir — about
issued a release that said the job had been done on a well known as
“The MC252 well appears to have reached a static
condition — a significant milestone,” BP said in its release. “The well
pressure is now being controlled by the hydrostatic pressure of the
The company also said it was possible that it would
have to pump more mud into the well during a monitoring period. It
could take several days to assess whether the operations permanently
plugged the well, which spewed nearly 5 million barrels of crude oil
into the Gulf, some 20 times more than the nation’s previous largest
offshore oil spill.
The company also will decide, in consultation with
federal officials, whether to pump cement into the well before it
completes a relief well.
completes a relief well and delivers a final “bottom kill.”
“And there should be no ambiguity about that,” Allen
said. “I’m the national incident commander, and that’s the way this
Although a massive 75-ton “stacking cap” sealed the
well in July, Allen said it remained unclear where the flow was coming
from inside a well running some two and a half miles below the
seafloor. A static kill can plug in the well’s inner casing, he said,
but an internal rupture also might be allowing oil or gas up the
annulus, the open space between the casing that usually carries oil and
gas and the larger bore hole that surrounds it.
Earlier in the week, Wells had suggested that the static kill alone might be enough to finish off the well.
Allen, however, supported by a team of federal scientists led by Energy Secretary
has argued that the only assured permanent plug is for the relief well
to penetrate the annulus and pump in more mud and cement.
“We need to go into the bottom to make sure we fill
the annulus, the casing and any drill pipe there and then follow that
with cement,” Allen said. “This thing won’t truly be sealed until those
relief wells are done.”
Allen said earlier that BP had completed cementing
in casing for its primary relief well, which is 100 feet from its
target some two miles down.
The oil giant estimated that it would take another week or more to finish drilling the well and start the final bottom kill.
(c) 2010, McClatchy-Tribune Information Services.