Containment Dome Has Not Stopped the Oil Spill Yet

Yesterday BP's engineers lowered a containment dome over the worst of the leaks from the sunken oil rig. It was hoped that the dome could corral around 85% of the leaking oil. Unfortunately, a buildup of hydrates prevented the dome from working properly.

The crystals, which are called hydrates and resemble slush, obstructed the flow of the oil, Suttles said. They also made the dome too buoyant, which prevented it from settling deeply into the seabed to form a water-tight seal.

Hydrates form when gas and water mix at low temperature and high pressure, as occurs at the bottom of the sea. The water temperature at the wellhead is about 42 degrees, with pressures in excess of 2,300 pounds per square inch. Pressure on the surface of the water is about 14 pounds per square inch.

Suttles said experts will spend the next few days looking at possible solutions, while other efforts continue to control the spill. A relief well intended to intercept the leaking one and seal it won't be completed for three more weeks.

This is not good at all. I hope that they can find a way to make this work since the alternative is oil continuing to spill for another month or more until the completion of a relief well. Meanwhile, tar balls are appearing on some beaches:

Meanwhile, a Coast Guard official reported tar balls believed to be from the spill were washing up on an Alabama barrier island.

About half a dozen of the balls had been collected by Saturday afternoon at Dauphin Island, though the substance of the balls still needs to be tested.

If the containment chamber does not work, another short-term solution is to attempt plugging the wellhead from above, which has its own set of risks.

The other option is what Mr. Suttles called a “junk shot,” which he likened to stopping up a toilet. The procedure would involve reconfiguring the blowout preventer and injecting heavy material like rubber into it, then pumping heavy drilling mud down into the well to overcome the pressure of the oil from below. That might stop the leak.

But the mud would have to be pumped through new pipes from the surface, as existing pipes that might have been used for such an operation collapsed along with the riser when the drilling rig sank April 22.

As with all the work being performed at the seabed, the preparations would have to be done by robotic vehicles in extremely challenging conditions. At a depth of 5,000 feet, the pressure is about 2,300 pounds per square inch, or more than 150 times atmospheric pressure.

Both procedures could make the problem much worse by opening the leak further. On Monday, a senior BP official told members of Congress that the well could conceivably spill as much as 60,000 barrels of oil a day, more than 10 times the estimate of the current flow.

Among the maddening aspects of the Deepwater Horizon disaster is that the Interior Department allowed the operation to go forward without an environmental review. Despite the current mess, the federal government has continued waiving environmental reviews since the rig's explosion.

Since the Deepwater Horizon oil drilling rig exploded on April 20, the Obama administration has granted oil and gas companies at least 27 exemptions from doing in-depth environmental studies of oil exploration and production in the Gulf of Mexico.

The waivers were granted despite President Barack Obama’s vow that his administration would launch a “relentless response effort” to stop the leak and prevent more damage to the gulf. One of them was dated Friday — the day after Interior Secretary Ken Salazar said he was temporarily halting offshore drilling

The exemptions, known as “categorical exclusions,” were granted by the Interior Department’s Minerals Management Service (MMS) and included waiving detailed environmental studies for a BP exploration plan to be conducted at a depth of more than 4,000 feet and an Anadarko Petroleum Corp. exploration plan at more 9,000 feet.

MMS justifies the waivers on the grounds that these operations are not using new technology. However, as we have seen in the Deepwater case, such deep drilling operations are inherently risky, and federal regulators ought to consider the environmental impacts if something goes wrong.

Finally, here is a graphic illustrating some of the spill's costs.