WASHINGTON — The battle to contain BP's massive Deepwater Horizon oil spill in the Gulf of Mexico is approaching two critical junctures in coming days that could affect how the months-long catastrophe ends.
The first will happen for sure: the connection of a third ship to the jury-rigged containment system through which BP has been capturing about 24,000 barrels of oil per day since early June. That may take place as soon as this weekend, depending on how rough the seas are, and it would raise the amount of oil that BP can collect from the well to as much as 53,000 barrels per day. That's 88 percent of the 60,000 barrels per day that the government says is the current best guess of the maximum amount that's gushing from the well.
The second may not happen: replacing the "top hat" component of that containment system with a new cap that would fit more snugly but whose installation would require that the well be uncapped for as long as 10 days, allowing tens of thousands of additional barrels of crude to spew into the Gulf.
The new containment cap was the subject of Cabinet-level meetings in Washington last week, including one with President Barack Obama, and the decision remains uncertain.
Retired Coast Guard Adm. Thad Allen said Wednesday that he'd had more meetings on the topic with BP officials Tuesday in Houston and that more meetings were scheduled for when he returned to Washington this week.
"We are still reviewing the technical specifications . . . the amount of time . . . and the weather window that it would take" for installation, Allen said. He was unwilling to lay odds on whether the new cap would be approved.
"I wouldn't want to attach a percentage right now," he said.
Adding the third ship, the Helix Producer I, has been planned for weeks and was supposed to have happened by June 30. High seas generated by Hurricane Alex and then by an unnamed storm system near Mexico's Yucatan peninsula so far have thwarted the final few days of work, however.
Allen said he flew to the Deepwater Horizon site on Wednesday in part to assess weather conditions.
In a conference call from the Discoverer Enterprise, the drilling ship that's taking on oil from the well through the "top hat," Allen said that the waves buffeting the area were 4 to 6 feet tall, still too high to complete the final connections linking the Helix Producer I to the Deepwater Horizon's failed blowout preventer.
Forecasts anticipate calmer seas in the next 48 hours, he said, after which the last of the work hooking up undersea hoses should take three days.
The addition of the Helix Producer I is likely to re-energize the controversy over just how much oil is escaping from the well. A government panel of scientists estimated last month that the well is leaking anywhere from 35,000 to 60,000 barrels per day.
Once the Helix Producer I is connected, however, the lower end of those estimates could well be proved moot, increasing pressure on the Obama administration and BP to determine the high end of the gusher more precisely.
While the two vessels currently collecting oil have a combined maximum capacity of just 28,000 barrels per day — below the government's minimum estimates — the three ships together easily could capture 40,000 to 53,000 barrels a day, well in excess of the minimum range.
The Helix Producer I can take 20,000 to 25,000 barrels per day, officials have said. The Discoverer Enterprise has a stated capacity of 18,000 barrels per day, though it's been collecting an average of about 15,000 barrels on most days, and the Q4000 drilling rig, which is burning the oil it collects, can dispose of 10,000 barrels a day, though in recent days it's been averaging something more than 8,000 barrels daily.
Allen tacitly acknowledged that people watching the oil well via a video feed on BP's website — a near-constant presence during newscasts from the Gulf on cable television — will still see crude billowing into the water after the Helix Producer I begins operating.
He tried to put the best possible face on that likelihood, however, saying that as long as oil is coming out of the cap, it means that seawater isn't leaking in, something that would risk the formation of icelike crystals known as hydrates, which would render the top hat unusable.
"Oil in the water is never a good thing," he said. "But some oil that comes out around that seal right now is actually the price of being able to produce up to 25,000 barrels a day and maybe up to close to 53,000 when we get the Helix Producer online. . . . We've got to have a little bit of oil coming out, not water coming in, to avoid the hydrate problem."
The new containment cap under consideration would seal off the well completely because it would be bolted directly to the blowout preventer rather than sitting loosely atop a sheared-off pipe.
Officials have said previously that the new containment cap is necessary for BP to reach the 80,000-barrel-per-day capacity that the government has required the oil giant to achieve. Allen didn't say how that requirement would be affected if officials decide that installing the cap is too risky.
Allen also gave a tepid review of a massive oil-skimming vessel from Taiwan that began tests over the weekend in the Gulf. Critics of the Obama administration's oil spill response have charged that the administration's unwillingness to waive legal restrictions on foreign vessels in U.S. waters delayed the deployment of the A Whale. In fact, the ship, an oil tanker, was being reconfigured in Portugal to skim oil and arrived in the Gulf only last week.
Allen said the tests had shown the A Whale to be so large that it needed "large patches of oil to be effective" and "requires a large amount of maneuvering room."
"I don't have the final evaluation from our research and development folks that are on site," he said of the A Whale tests, "but, in a word, I would say inconclusive."
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