By BRETT CLANTON
HOUSTON CHRONICLE
BP says it is working on at least five possible approaches for halting the spew of oil from a damaged well deep in the Gulf of Mexico that is feeding one of the worst spills in U.S. history.
The company says all of the plans are moving forward simultaneously, even though some may turn out to be unnecessary or unsuccessful. But several of the ideas, once considered backup solutions, have begun to figure more prominently into the sweeping effort, including work on a subsea collection system for leaking oil and the drilling of a relief well to stop the flow from the damaged one.
That work is centered at BP's offices in west Houston, where hundreds of engineers and technical specialists, representing 160 companies, are assembled to attack the growing crisis.
“This is not just about BP,” said Bob Fryar, senior vice president of BP's exploration and production business in Angola, brought in to the center for his expertise in deep water drilling.
After more than 10 days of continuous work without success, BP officials still hope to seal the well at any moment using robot submarines to activate an array of shut-off valves atop the well, called a blowout preventer.
Fryar and other BP executives said they still don't know why the blowout preventer did not seal the well when workers tried to activate it on April 20, when a blowout in the well engulfed the Deepwater Horizon in flames, killing 11 and sinking the structure two days later.
In recent days, half a dozen remotely operated vehicles have been engaged in the effort, but BP said it still hasn't worked, perhaps because the blowout preventer was damaged in the initial blast.
Within 24 hours of the explosion, robot submarines failed to execute two backup methods for engaging the blowout preventer, he said.
Later, when trying to diagnose the problem, BP discovered leaks on the hydraulic controls, Fryar said, which since have since been fixed.
‘Nothing unique'
Investigations are still trying to determine causes of the disaster, but Fryar said “there is nothing unique about the situation that was taking place at the time that would have prohibited the (blowout preventer) system from working as designed.”
Meanwhile, BP said Monday four other solutions for halting the flow of oil from the well are gathering momentum.
Those include installing huge containment boxes over leaks to collect the oil and send it through a mile of pipe to a ship above; using long wands to spray chemical dispersants on the leaks at the sea floor to break up oil and keep it from rising to the surface; lowering a second blowout preventer onto the damaged one to seal the well; and drilling a relief well to intercept the damaged one and plug it.
Monday night, the company planned to install a valve on the end of a leaking drill pipe — one of three leaks in equipment down below — that could help slow the flow from the well.
That would be a first step in preparing to place one of two containment boxes over a leak causing the majority of the spill by as soon as this weekend, BP officials said. A second box would be placed over a smaller leak close to the wellhead several days later.
“Over the next seven days or so, we'll be actually trying to connect all these pieces up and start up that system,” said Doug Suttles, chief operating officer of BP exploration and production, during a press briefing Monday. But he cautioned the technology has never been tried in such deep water.
In addition, deep-sea injection of chemical dispersants directly at the source of the leaks continues, and officials are hoping an aerial assessment will soon give them a sense of how effective that has been.
Blowout preventer repair
Fryar said an initial test showed “a clear difference” in the amount of oil traveling to the water's surface from the wellhead a mile below.
BP says it will try this week to take pressure measurements within the 50-foot tall blowout preventer atop the well to determine if it is safe to remove a top portion of the stack called the lower marine riser package. Removing the piece would allow BP to lower another blowout preventer on top of the damaged one to seal the well, but also might carry a danger of rupturing the well further.
As a last-ditch effort, BP began Monday afternoon drilling a relief well into the damaged well with the hope of permanently sealing it, though that process could take 60 to 90 days, company officials said.
As a last-ditch effort, BP began Monday afternoon drilling a relief well into the damaged well with the hope of permanently sealing it, though that process could take 60 to 90 days, company officials said.
brett.clanton@chron.com
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