Is there a quick way to stop the flow of oil in the Gulf of Mexico? One maverick scientist says the answer may be as simple as dropping steel balls into the gushing well and that there's no harm in trying. But some petroleum engineers say the idea is too good to be true and could make matters worse.
Willard Wattenburg, an electrical engineer and nuclear physicist from Greenville, California, made a name for himself by directing the capping of the more than 500 hundred burning oil wells in Kuwait after the Gulf War in 1991. His scientific connections helped put his idea on the desk of Energy Secretary Steven Chu. The reasoning behind Wattenburg's proposal is seductively simple. If the steel balls are big enough in diameter, their weight will pull them downward even through the upward-rushing torrent of oil and gas. So they'll settle into the well at some deep level and begin to clog it. Two hundred tons of the things should slow the gusher enough that it can then be stopped with a more conventional injection of mud, says Wattenburg, a research scientist at the Research Foundation of California State University, Chico, and a consultant to Lawrence Livermore National Laboratory.
The big question is how large must the balls be to fall through the flow of oil and gas, To find out, Wattenburg suggests using a connection from the surface to the so-called blow-out preventer (BOP) on top of the well to pump in steel balls with a range of diameters up to about 3.8 centimeters (1.5 inches). Then engineers can simply observe which ones come flying back out of the top of the broken pipe at the top of the BOP, where oil is currently flowing from the well. If the larger balls don't come out, they must be sinking the well, Wattenburg explains. And if all the balls come out, well, no harm done. "I would claim that you have an all-win, no-lose experiment for little expense," says Wattenburg, who estimates the cost at $100,000.
Wattenburg's track record suggests that his idea should not be dismissed out of hand. In 1991, scientists estimated that it would take 5 years to extinguish and cap more than 500 oil wells that the Iraqi army had left burning in Kuwait when it fled before the U.S-led invasion. Wattenburg oversaw efforts that got the job done in 7 months. In 1994, he invented a temporary bridge made from railroad flatbed cars that was used a year later to repair a section of an interstate highway in California that floods had destroyed. As a Livermore scientist in the 1960s, Wattenburg developed a means to monitor the size of underground nuclear explosions from afar.
Wattenburg, who also hosts a radio talk show and is not afraid to recount his own accomplishments , is well connected. He forwarded his idea to a friend who on 2 June sent it directly to Chu. Chu e-mailed back to say DOE had considered such a scheme but that there were complications. Wattenberg says he would like to know what the complications are. "All I'm looking for is proof that it won't work."
When it comes to possible complications, petroleum engineers can name a few major ones. For example, oil and gas are not rushing up the well's central pipe, or "production casing," which has a diameter of 25 centimeters. Rather, they're flowing through the space between that pipe and the larger outer casing, which has a diameter of 38 centimeters. Balls fed in through the BOP can take either route, notes Julius Langlinais, a petroleum engineer retired from Louisiana State University, Baton Rouge. So given the chance, they'll take the path of least resistance and go down the central pipe where there isn't any flow, he says. "They would not fall where it's going to make any difference," Langlinais predicts.
Simply pumping the balls into the well would also be difficult, Langlinais says, because those heavy enough to fall through the gushing oil would also be heavy enough to fall out of any slurry used to pump them. Finally, Langlinais says that balls that fall all the way down the well won't plug it because the well can hold an essentially limitless number of them.
Wattenburg dismisses all these points. Balls that go all the way down the center of the well would eventually get blown into the outer region where they'd work their magic, he says. And, he says, Langlinais simply doesn't understand what different types of pumps can do. "I think I can give you evidence that these [objections] are just not relevant," Wattenburg says.
Perhaps most important is Wattenburg's claim that his experiment cannot make matters any worse. That's not necessarily so, says Martin Chenevert, a petroleum engineer at the University of Texas, Austin. "Once you get these steel balls in there, you'll never get them out," he says. And that could greatly complicate future efforts to drive cement into the surrounding earth to help seal the well, he says.
Given what's happened since the Deepwater Horizon drill platform exploded on 20 April, the claim that things couldn't get worse in the Gulf of Mexico seems pretty dicey.
For more on the gulf oil spill, see our full coverage .