Challenge of cleaning up Gulf of Mexico oil spill ‘unprecedented’ at such depths

By David A. Fahrenthold and Juliet Eilperin
Washington Post Staff Writer
Saturday, May 15, 2010 ELMERS ISLAND, LA. — The oil spill in the Gulf of Mexico has not yet caused coastal damage on the scale of the Exxon Valdez disaster. But scientists say it is becoming something different and potentially much more troubling: the first massive U.S. oil spill whose effects so far are largely hidden underwater. Three weeks after crude oil began billowing into the gulf, the spill has threatened the long-term livelihoods of thousands of gulf residents, enmeshed three major global companies in litigation and could destroy parts of Louisiana’s ecologically valuable marshes. The 1989 Valdez accident looks simple by comparison. No one questioned the cause — an Exxon tanker that ran aground — and the oil was released in one enormous but finite swoop into Alaska’s pristine and remote Prince William Sound. … Because of the leak’s extreme depth, and the effects of dispersants, the spill is breaking the maxim that oil floats. Instead, scientists fear it is settling on sensitive corals or poisoning ecosystems that produce shrimp, snapper and sport fish, all too deep for scientists to watch or help. “This monster’s turned invisible,” said Plaquemines Parish President William “Billy” Nungesser on Thursday. “How do you fight that monster when it’s invisible?” The spill’s impacts on underwater creatures might not be fully understood for years, said Ronald J. Kendall, a professor at Texas Tech University. “It’s a massive eco-toxicological experiment underway.” … Some scientists say they’re troubled by how little they know about this spill. Oil on the surface can be spotted by planes and satellite images. But there is relatively little equipment in the gulf region that can tell where oil has traveled below the surface. … “By dispersing the stuff at depth, it creates essentially smaller globules of oil [and] it makes the oil more likely to be affected by even slow-moving currents,” said James H. Cowan Jr., a professor of oceanography and coastal sciences at Louisiana State University. “We just don’t know where it is, and we don’t know where it’s going.” They fear it could be settling on underwater formations far out on the gulf floor, places with such fanciful names as the Alabama Alps and the Flower Gardens. These include coral formations that can look like standing forests of trees and support populations of fish such as red snapper. …