HOUSTON -- Engineers hoping to contain oil gushing from the mangled pipe beneath the Gulf of Mexico appeared to make important headway Sunday, as robot submarines jammed a suction tube into the pipe in an attempt to pull the oil to a ship on the surface.
Officials for the oil company BP said they could not estimate how much oil and gas was flowing through the tube, nor what percentage of the leak was being contained, until today or Tuesday at earliest. They originally said the plan might suck up as much as 75 percent of the leaking oil.
Without the number of gallons retrieved, it remained unclear Sunday whether the nation's brightest minds would be capable of solving an engineering conundrum that is spewing an estimated 210,000 gallons of oil a day -- and perhaps more -- into Gulf waters from a canyon 5,000 feet below the sea.
Although relatively little has washed up on land so far, scientists are growing worried about the effects of massive plumes of oil hovering below the surface in areas teeming with life from plankton to turtles, dolphins and whales.
Interior Secretary Ken Salazar and Homeland Security Secretary Janet Napolitano warned in a joint statement Sunday that the latest in a series of short-term attempts at stopping the leak was "not a solution, and it is not clear how successful it may be."
BRAINS SENT TO HELP BP
In recent days, the Obama administration has assembled a Dream Team of scientists to deal with the leak, including experts in robotics, physics, X-ray technology and the hydrogen bomb. Energy Secretary Steven Chu, a physicist who won the Nobel Prize, met with BP engineers in Houston last week, and promised that the "intellectual horsepower of the country is engaged in solving this problem."
But unlike many science and engineering problems that can be worked out in a lab or on a blackboard, this one is unfolding far from the reach of a human hand, in real time, with a potentially high penalty for failure.
"It's not just theory, it's reality that has to be dealt with," said Henry Petroski, a Duke University professor of civil engineers and history. "This is a really tough problem."
The leak was triggered April 20 by a blowout of a BP well that caused an explosion on the Deepwater Horizon, a mobile oil rig that had just finished drilling an 18,000-foot hole about 48 miles off the Louisiana Coast. The accident killed 11 workers, and the $600 million rig now lies at the bottom of the sea.
FIRST FIXES FAILED
BP's engineers first focused on using robot submarines to shut off the blowout preventer, an apparatus that had failed to sever or plug the well pipe. More recently, a 100-ton box lowered over the leak in an attempt to siphon it to the surface failed when icy gas crystals called hydrates clogged it.
This weekend's plan involved running the long suction tube from a ship to the damaged riser pipe on the ocean floor. A 4-inch diameter insertion tube was guided into the 21-inch diameter riser, which also was plugged with rubber diaphragms.
If all goes as planned, a flow of nitrogen in the tube will lift the oil to the ship. Methanol will be added to help prevent the formation of hydrates, and heated sea water will promote the flow of oil.
At a Houston news conference, company leaders said they first inserted the tube around midnight Saturday. It operated for four hours, and was just beginning to bring oil to the surface ship when an undersea robot knocked the tube loose. Engineers reinstalled the tube a few hours later.
BP officials said the flow rate was slowly increasing. But they couldn't say how much they had collected. "I don't have any idea at this point," said Kent Wells, BP's senior vice president for exploration and production.
Even if successful, BP must also contain a second leak on the ocean floor.
MOST OF SPILL HIDDEN
The huge and growing stain of oil, meanwhile, continues to hover in and around the shores and inlets of Alabama, Louisiana and Mississippi. The latest oil landfall was reported at Grand Isle, La., where a number of tar balls washed ashore, said U.S. Coast Guard Petty Officer Erik Swanson.
At the same time, scientists have begun measuring the vast quantities of oil hidden to the human eye. Vernon Asper, an oceanographer and marine professor at the University of Southern Mississippi, was part of a group of scientists who landed at Cocodrie, La., Sunday, after completing a two-week research trip in the Gulf. Asper said they documented plumes of oil between 2,000 and 6,000 feet below the water's surface, covering an area four miles wide and 15 miles long.
Bacteria in the water naturally break down oil, but that process sucks up large amounts of oxygen. Such a scenario could cause dead zones similar to a seasonal one caused by nitrogen-rich runoff down the Mississippi River.
"We're concerned about that, because everything that lives down there at these depths of the water needs oxygen, so if you use up all the oxygen they're going to be impacted."
Ralph Portier, an environmental science professor at Louisiana State University, said he feared that the deep oil plumes could emerge years or even decades from now, potentially threatening coastlines for generations.
But Portier also stressed that researchers were dealing with a novel situation riddled with unknowns. "We don't know enough," he said. "This is a scenario where reality is ahead of the science," he said.
WHO PAYS? AND HOW MUCH?
In Washington on Sunday, Senate leaders disagreed on how hard the government should press oil companies to pay for such environmental disasters in the future.
Sen. Charles Schumer, D-N.Y., the third-ranking Democrat in the Senate, said on NBC's "Meet the Press" that it is time to lift the $75 million congressionally mandated cap on oil company liability. On the same program, Senate Republican Leader Mitch McConnell of Kentucky said that caps can be an important incentive to keep the private sector exploring for energy resources.
"The danger in taking the cap too high is that you end up with only massive, very large oil producers able to meet that cap and produce in the Gulf," McConnell said.
BP chief executive Anthony Hayward and other executives have said they are taking full responsibility for cleaning up the spill and will pay what they call "legitimate" claims.
'TOP HAT' AND 'HOT TAP'
Wells, the BP vice president, stressed that engineers continue to pursue "multiple options" to contain the spill, including a second-generation insertion tube; a smaller version of the failed containment box, dubbed the "top hat"; and a method known as a "hot tap," in which robots would bore a new hole into the riser pipe and attach a new pipe to carry oil up to the surface ship.
He also said the company's priority remains sealing the well permanently. A first attempt to do that, the so-called "top kill" procedure, could begin in seven to 10 days, Wells said. It will likely start with engineers attempting to pump thousands of barrels of fluid into the well at high pressure, attempting to overcome the well's natural release pressure and stem the flow, before entombing the opening with cement.
If the pumping alone does not suffice, Wells said the company would likely proceed with a plan to attempt to block the well pressure with a mixture that would include rubber and golf balls.
By JIM TANKERSLEY, RAJA ABDULRAHIM AND RICHARD FAUSSET
Los Angeles Times