They give this explanation on the possibility of long-lasting "dead zones" in the Gulf of Mexico as a result of the oil geyser:
Big oil spills of the past are poor guides to the Deepwater Horizon disaster because all of them occurred in shallower water. This time, with the leak at 5,000 feet, a great deal of the oil hasn't reached the surface. Scientists say that under the immense pressure at that depth, much of it has turned into a diluted mist of hair-width droplets that are staying submerged in vast clouds. As recently as June 6, BP chief executive officer Tony Hayward said there was no evidence of such plumes in the Gulf. On June 8, however, the National Oceanic & Atmospheric Administration announced that they had indeed been found thousands of feet down.
Biologists have little experience with undersea plumes. "This is going to be groundbreaking science," says Roger Helm, chief of the environmental quality division of the U.S. Fish and Wildlife Service. Microbes that customarily feed on oil seeping from the seabed are expected to consume most of this oil, but that creates its own problems: The bugs use up oxygen needed by other sea creatures, potentially creating dead zones devoid of animal life, says Frank Muller-Karger, professor of biological oceanography at the University of South Florida. Marine biologist Rick Steiner says two-thirds of the fish and wildlife species injured in the Exxon Valdez spill 21 years ago have yet to fully recover. Stony Brook's Fisher says that the spill might promote bacteria that convert inorganic mercury into toxic methylmercury, which is taken up in the flesh of fish and other seafood. [my emphasis]
This helps clarify why BP has been trying to downplay the existence of the underseas "plumes." Skimming oil of the surface of the water sounds to the layperson like something feasible. Massive amounts of oil diffused in the water in microscopic droplets that will cause the oxygen to be sucked out of large portions of the Gulf and kill everything in them larger than the microbes that feed off the oil droplets somehow sounds a lot scarier. Look for efforts to brush those oil plumes off as oil that's so diffused it doesn't cause much of a problem. We've heard some of that already.
Coy and Barrett also have this to say about the relief well project: "Drilling two relief wells to stop the flow of oil is almost certain to get the job done, just not necessarily right away." In other words, the good news is that it's certain to work; the bad news is that it could take years to make it work.
They don't specify years as the potential time frame, but rather emphasize the uncertainty, which comes from the following reality:
That's because it's fiendishly difficult to intercept the broken well, which is narrower across than a soccer ball, by drilling another well more than three miles beneath the ocean floor. Both relief wells might miss—as other emergency wells have—requiring a second, third, or fourth try, says Dave Rensink, president-elect of the American Association of Petroleum Geologists. It took Mexico's state-owned oil company, Petróleos Mexicanos, or Pemex, nine months to plug its Ixtoc I well after an explosion and fire in 1979. The company's first relief well failed, so it had to drill a second. Eventually more than 140 million gallons of crude spilled into the Gulf of Mexico.
That well, however, was not nearly as deep as the BP oil geyser.
The worst natural disaster in U.S. history. The worst economic recession in generations. Now, the worst man-made disaster in U.S. history. ...
Hurricane Katrina showed South Mississippi communities, churches, volunteer agencies, local governments, business leaders, state leaders and congressional leaders have an uncanny ability to work together when push comes to shove. But then, we know hurricanes — how to prepare, how to dig out and, as Gov. Haley Barbour put it many times in his Yazoo drawl, how to "hitch up our britches and get to work" on recovery.
With massive oil leaks — not so much.
Pender's local readers would be aware of a situation that might not be so immediately clear to people in other parts of the country and the world: the community contributions to the post-Katrina clean-up along with massive federal aid is still a long way from having repaired all the physical damage from Katrina.
It certainly seems to me that Mississippi has been inadequately served by having Republican Gov. Haley Barbour in charge of advocating for relief on behalf of the state. In the aftermath of the Katrina disaster in 2005, he was eager to make the Cheney-Bush administration look good. In the ongoing BP oil disaster, he's eager to protect the oil and gas industry from accountability and regulation. The needs of Mississippi's communities and most of its citizens take a distinctly secondary priority for him.