Wednesday, July 28, 2010

Gulf Update

Before suspending operations due to tropical storms, Development Driller III had drilled the first relief well to a depth of 17,864 feet below the Gulf surface and Development Driller II had drilled the second relief well, a redundant measure taken at the direction of the Obama Administration, to a depth of 15,963 feet below the surface. As shown above, back on July 10 (i.e., two weeks ago), these wells were 17,810 and 15,961 feet, respectively. Storm and other delays have resulted in a total of only 56 feet of drilling in the last two weeks.

DD II is currently holding operations and waiting on the results of the DDIII relief well. DDIII has latched onto the wellhead, and is preparing to remove the storm packer and perform a well conditioning run before drilling down to 18,000 and intersecting with the damaged Deepwater Horizon well. Should DDIII fail for any reason, DDII will resume drilling.

Since the leaking well itself has now been capped, it’s somewhat less urgent to complete these operations quickly, so BP can afford to exercise a little caution while completing these final maneuvers. Also, it’s been reported that the oil slick on the Gulf is breaking up faster than expected, an encouraging sign relative to protection of the shore, but not necessarily to marine life.

In their response, the Obama Administration and BP made the perhaps unconscious decision to prioritize protection of the shore, beaches and wetlands over protection of marine life and the food chain. The released petroleum can take one of two forms – either as separate-phase oil floating of the surface, the visible slick, or as hydrocarbon molecules dissolved in the ocean water, the so-called “plumes.” The former is visible and easily confirmed; the latter is invisible and BP has even denied its existence. The response actions to date have largely centered around the use of skimmers, booms and on-shore actions to recover the separate-phase oil.

But the response has also made extensive use of chemical dispersants to accelerate the conversion of separate-phase oil into dissolved-phase hydrocarbon plumes. This puts the visible slick out of sight and possibly out of mind, but does not get rid of the problem. The hydrocarbons dissolved in the ocean water are not only toxic but also include known and suspected carcinogens such as benzene, ethylbenzene, and various polynuclear aromatic hydrocarbons (PAHs), such as naphthalene.

Marine life, from microscopic phytoplankton to the largest of fishes and mammals, can absorb the dissolved hydrocarbons through a variety of tissues, including the body surface, gill structures, and the digestive system, and the hydrocarbons thus enter the food chain. The hydrocarbons also have a tendency to bio-accumulate in various organs and membranes, so that as the smaller fish are eaten by the larger fish and so on, the hydrocarbons are passed on up to higher-level predators, including sharks, some whales (other whales feed at the bottom of the food chain and get their hydrocarbons directly from the plankton), dolphins, sea turtles, and man.

Worse, the dispersants themselves, such as Nalco’s Corexit, also contain toxic and potentially carcinogenic hydrocarbons. According to the New York Times, the ingredients in the Corexit 9500 dispersant, the primary chemical product used, include the solvent propylene glycol, light petroleum distillates, and the detergent dioctyl sodium sulfosuccinate. Material Safety Data Sheets released by Nalco identify the three substances as potentially hazardous, advising users to avoid getting the dispersant "in eyes, on skin, on clothing."

According to marine toxicologist Susan Shaw, "Corexit dispersants used in the Gulf contain solvents – petroleum distillates that are animal carcinogens – capable of killing or depressing the growth of a wide range of aquatic species. For vulnerable species such as phytoplankton, corals and small fish, the combined effects of Corexit and dispersed oil can be greater and last longer than the effects of oil alone."

Approximately 1.84 million gallons of dispersant have been applied since the release began - 1.07 million on the surface and 771,000 to the sub-surface. In essence, we’re adding hydrocarbons to hydrocarbons to make the visible plume disperse and preserve our beaches, but in the process we’re poisoning the Gulf.

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