How a big oil spill turns good cleanup plans upside down

Two weeks ago, BP CEO Tony “I’d like my life back” Hayward tried to deny independent scientists’ findings that oil from the Deepwater Horizon spill wasn’t confined to the surface of the water. Today, the National Oceanic and Atmospheric Administration sided with the independent reports—with the head of NOAA adding, “We have always known there is oil under the surface.”

As Mother Jones points out, it’s pretty inevitable that there would be oil underwater, given that the whole point of using chemical dispersants is to break the oil down into droplets and allow those droplets to sink, so they can be more easily eaten by the hydrocarbon-guzzling microbes that live in the water—a strategy that works quite well in smaller oil spills, using the smaller doses of dispersants approved by the EPA.

But dose makes the poison—both with dispersants and oil droplets, themselves. The plumes, in this case, are so large that, as microbes devour them, that process depletes all the oxygen in the surrounding water. Essentially, it’s the same thing that happens in the Gulf Dead Zone.

Likewise, oil sunk by dispersants doesn’t wash up on the beach—again, a good thing in smaller spills. Here, though, it ends up creating a threat to underwater ecosystems, especially coral reefs.

(PHOTO: Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite on June 7, 2010. “At least part of the oil slick is pale gray. A large area of oil is southeast of the Mississippi Delta, at the site of the leaking British Petroleum well. Traces of thick oil are also visible farther north.”)