leaking cap from the gushing Gulf oil well Saturday, starting a painful
trade-off: Millions more gallons of crude will flow freely into the sea
for at least two days until a new seal can be mounted to capture all of
it.
There's no guarantee for such a delicate operation deep below the water's
surface, officials said, and the permanent fix of plugging the well from
the bottom remains slated for mid-August.
"It's not just going to be, you put the cap on, it's done. It's not like
putting a cap on a tube of toothpaste," Coast Guard spokesman Capt. James
McPherson said.
Robotic submarines removed the cap that had been placed on top of the leak
in early June to collect the oil and send it to surface ships for
collection or burning. BP aims to have the new, tighter cap in place as
early as Monday and said that, as of Saturday night, the work was going
according to plan.
If tests show it can withstand the pressure of the oil and is working, the
Gulf region could get its most significant piece of good news since the
April 20 explosion on the BP-leased Deepwater Horizon rig, which killed 11
workers.
"Over the next four to seven days, depending on how things go, we should
get that sealing cap on. That's our plan," said Kent Wells, a BP senior
vice president, of the round-the-clock operation.
It would be only a temporary solution to the catastrophe that the federal
government estimates has poured between 87 million and 172 million gallons
of oil into the Gulf as of Saturday. Hope for permanently plugging the
leak lies with two relief wells, the first of which should be finished by
mid-August.
With the cap removed Saturday at 12:37 p.m. CDT, oil flowed freely into
the water, collected only by the Q4000 surface vessel, with a capacity of
about 378,000 gallons. That vessel should be joined Sunday by the Helix
Producer, which has more than double the Q4000's capacity.
But the lag could be long enough for as much as 5 million gallons to gush
into already fouled waters. Officials said a fleet of large skimmers was
scraping oil from the surface above the well site.
The process begun Saturday has two major phases: removing equipment
currently on top of the leak and installing new gear designed to fully
contain the flow of oil.
BP began trying Saturday afternoon to remove the bolted top flange that
only partially completed the seal with the old cap. Video images showed
robotic arms working to unscrew its bolts. Wells said that could last into
Monday depending on whether the flange can be pulled off from above, as BP
hopes. If not, a specially designed tool will be used to pry apart the top
and bottom flanges.
Once the top flange is removed, BP has to bind together two sections of
drill pipe that are in the gushing well head. Then a 12-foot-long piece of
equipment called a flange transition spool will be lowered and bolted over
it.
The second piece of pipe inside the well head came as something of a
surprise, and raises the possibility that one of the sections of pipe
became jammed in the Deepwater Horizon's blowout preventer, though which
the well pipes run. The failure of the blowout preventer, a massive piece
of equipment designed to stop the unchecked flow of oil, is partly to
blame for the size of the spill.
"That will be an important question to ask when we pull the blowout
preventer up to the surface and we'll figure out where that pipe
ultimately landed," Wells said.
After the flange transition spool is bolted in place, the new cap - called
a capping stack or "Top Hat 10" - can be lowered. The equipment, weighing
some 150,000 pounds, is designed to fully seal the leak and provide
connections for new vessels on the surface to collect oil. The cap has
valves that can restrict the flow of oil and shut it in, if it can
withstand the enormous pressure.
That will be one of the key items for officials to monitor, said Paul
Bommer, a professor of petroleum engineering at the University of Texas at
Austin.
"If the new cap does work and they shut the well in, it is possible that
part of the well could rupture if the pressure inside builds to an
unacceptable value," Bommer wrote in an e-mail Saturday.
Ultimately, BP wants to have four vessels collecting oil within two or
three weeks of the new cap's installation. If the new cap doesn't work, BP
is ready to place a backup similar the old one on top of the leak.
The government estimates 1.5 million to 2.5 million gallons of oil a day
are spewing from the well, and the previous cap collected about 1 million
gallons of that. With the new cap and the new containment vessel, the
system will be capable of capturing 2.5 million to 3.4 million gallons -
essentially all the leaking oil, officials said.
The plan, which was accelerated to take advantage of a window of good
weather lasting seven to 10 days, didn't inspire confidence in the
residents of the oil-slicked coast.
"This is probably the sixth or seventh method they've tried, so, no, I'm
not optimistic," said Deano Bonano, director of emergency preparedness for
Jefferson Parish.
On Saturday he was inspecting beaches at Grand Isle lined with protective
boom and bustling with heavy equipment used to scoop up and clean stained
sand.
"Even if they turn it off today, we'll still be here at least another six
weeks, on watch for the oil," he said.
"Shutting off the oil is a very important step, but we should not assume
this disaster is over," said Larry Schweiger, president of the National
Wildlife Federation. "I think it's important to recognize that there's an
enormous amount of oil still in the Gulf."
---
Associated Press Writer Holbrook Mohr in Belle Chase, La. contributed to
this report.
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