Thursday, July 1, 2010


The behavior of oil in deep water is a subject few of us thought about until very recently. However, the oil industry has thought about it before this year. In June of 2000, the Minerals Management Service (part of the U.S. National Oceanic and Atmospheric Administration, or NOAA) contracted with SINTEF and ChevronTexaco to explore just what would happen if there were an oil well blowout in deep water (see Project "Deep Spill"). In this planned experiment off the coast of Norway, "mixtures of crude oil and natural gas, diesel oil and natural gas, ... were released at approximately 800 meters water depth." On page 150 of their final report of that project, in a section entitled "Further Research", a paragraph begins with the following interesting observation.

"Prior to the sea trial, there were some doubts about whether the oil would reach the sea surface. It apparently did so during these experiments, but if the size of the oil droplets formed at the exit had been sufficiently small, the oil might not have surfaced."

Recent observations in the Gulf of Mexico of an unplanned experiment releasing a large quantity of oil at a depth of 1,500 meters suggest that a significant quantity of the oil has not reached the surface. Given that a large volume of oil dispersants have been intentionally added at the site of the Deepwater Horizon blowout, and that oil dispersants are designed and applied specifically to make the oil break up into smaller droplet sizes, one might anticipate that a significant portion of the oil released in the BP blowout would not reach the surface.

So it is more than a little surprising that BP's chief executive would, weeks after the blowout took place, be so ill-informed about the behavior of oil in deep water as to belittle claims that plumes of oil might exist beneath the surface of the Gulf of Mexico.

A key purpose of adding the dispersants is to make the oil break up into smaller droplets so that bacteria and physical action can break it down before it can harm wildlife or coastal habitats. It appears that these smaller droplets also keep a portion of the oil from surfacing, perhaps a good thing for plants along the coast, though maybe not so good for plankton and fish living out in the Gulf.

In any event, it should come as no surprise that scientists observing the spill find plumes of oil under the surface (see USF, and UGA). Oil experts discovered that could happen in an experiment almost 10 years ago, see Deep Spill Technical Report.

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