BP Reports Some Success in Capturing Leaking Oil
By SHAILA DEWAN
Copyright by The New York Times
Published: May 16, 2010
http://www.nytimes.com/2010/05/17/us/17spill.html?th&emc=th
NEW ORLEANS — After more than three weeks of efforts to stop a gushing oil leak in the Gulf of Mexico, BP engineers achieved some success on Sunday when they used a milelong pipe to capture some of the oil and divert it to a drill ship on the surface some 5,000 feet above the wellhead, company officials said.
After two false starts, engineers successfully inserted a narrow tube into the damaged pipe from which most of the oil is leaking.
“It’s working as planned,” Kent Wells, a senior executive vice president of BP, said at a briefing in Houston on Sunday afternoon. “So we do have oil and gas coming to the ship now, we do have a flare burning off the gas, and we have the oil that’s coming to the ship going to our surge tank.”
Mr. Wells said he could not yet say how much oil had been captured or what percentage of the oil leaking from a 21-inch riser pipe was now flowing into the 4-inch-wide insertion tube. “We want to slowly optimize it to try to capture as much of the oil and gas as we can without taking in a large amount of seawater,” he said.
So far, the spill has not spoiled beaches or delicate wetlands, in part because of favorable winds and tides and in part because of the use of booms to corral the oil and chemical dispersants.
The capture operation on Sunday was the first successful effort to stem the flow from the damaged well, which has been spewing oil since a rig exploded on April 20 and sank.
The announcement by BP came on the heels of reports that the spill might be might much worse than estimated. Scientists said they had found giant plumes of oil in the deep waters of the gulf, including one as large as 10 miles long, 3 miles wide and 300 feet thick.
BP officials pointed out that even if the tube was successful, it was only a stopgap measure. The real goal, they said, is to seal the well permanently.
Preparations continued on Sunday on a plan to pump heavy drilling mud into the well through the blowout preventer, the safety device at the wellhead that failed during the accident.
In the procedure, called a top kill, the mud would be used to overcome the pressure of the rising oil, stopping the flow. The mud would be followed by cement, which would permanently seal the well.
Mr. Wells said Sunday that BP was a week to 10 days away from trying the maneuver.
The mud would be pumped from a drill ship, the Q4000, that is in place on the surface. Mr. Wells said the ship had more than 2 million gallons of mud on board — far more than needed — to pump into the well, which had reached about 13,000 feet below the seabed when the accident occurred.
In a brief interview, Mr. Wells said that a “junk shot,” an effort to clog the blowout preventer with golf balls and other objects before the mud is used, was still a possibility.
But in an apparent indication of the tube’s success, BP was already building a backup version.
The tube is basically a five-foot-long section of pipe outfitted with rubber seals designed to keep out seawater, attached in turn to a milelong section of pipe leading from the drill ship to the seafloor.
It was one of several proposed methods of stanching the flow of at least 210,000 gallons of oil a day that has been threatening marine life and sensitive coastal areas in Louisiana, Mississippi, Alabama and Florida. BP officials have emphasized that none of the methods have been tried before at the depth of this leak.
At the briefing, Mr. Wells was asked about reports from a research vessel that discovered the huge plumes of oil. He said that he did not know anything about them, but that the Unified Area Command, the cooperative effort involving BP and state and local agencies, was seeking more information.
The plume reports added to the many questions that have been raised about the amount of leaking oil, which many scientists have said is far higher than the official estimate of 5,000 barrels, or 210,000 gallons, a day. That estimate was reached using satellite imagery, flyovers and visual observation, company officials have said.
The reports also raised concerns about the use of oil dispersants underwater, which the Environmental Protection Agency approved on Friday after several tests. Normally, dispersants are used on the surface, and scientists have said that the effects of using them underwater are largely unknown.
Representative Edward J. Markey, Democrat of Massachusetts and chairman of the Subcommittee on Energy and the Environment, criticized BP, saying it had failed to respond substantively to his requests for more information about how it had reached its estimate of how much oil is leaking. He also said the company had refused to engage independent scientists who might offer a better assessment of the amount.
“BP is burying its head in the sand on these underwater threats,” Mr. Markey said in a written statement on Sunday. “These huge plumes of oil are like hidden mushroom clouds that indicate a larger spill than originally thought and portend more dangerous long-term fallout for the Gulf of Mexico’s wildlife and economy.”
BP began trying to insert the tube on Friday, but an effort to connect the pipe leading from the drill ship to the tube failed and the device had to be brought back to the surface for adjustments.
“This is all part of reinventing technology,” Tom Mueller, a BP spokesman, said on Saturday. “It’s not what I’d call a problem — it’s what I’d call learning, reconfiguring, doing it again.”
Around midnight Saturday, the tube was reinserted and worked for about four hours before it was dislodged after being mishandled by the submersibles, Mr. Wells said.
“At that time, we were just starting to get oil to the surface,” Mr. Wells said.
The oil was going to the Discoverer Enterprise, a drill ship, which has equipment for separating water from oil and can hold about 5 million gallons of oil.
Though that attempt failed, it was important because it demonstrated that features designed to keep hydrates from forming were working, Mr. Wells said. Hydrates, icelike structures of methane and water molecules that form in the presence of seawater at low temperatures and high pressures, forced BP to abandon an earlier effort to corral the leak with a 98-ton containment dome.
Henry Fountain contributed reporting from New York.
Monday, May 17, 2010
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