Saturday, July 31, 2010

Oil Spill Updates

A US Fish and Wildlife officer tries to rescue an oiled bird 

BP plans to try a static kill of the broken well on Tuesday.
Wells described the static kill as a multi-step process that will start with what he called an "injectivity test" to determine the speed at which technicians will force heavy drilling mud into the well in hopes of driving the crude oil in the well back into the reservoir. Once the optimal speed is determined, technicians would pump mud in until pressure in the well has dropped to zero, indicating that the well has been contained.

At that point, technicians will dump cement into the well to permanently close it.

Wells didn't say how long the static kill would take. He said engineers believe the wellbore holds about 2,000 barrels of oil, or about 84,000 gallons. BP has 12,000 barrels of drilling mud standing by for the procedure, he said.

The goal is to force all of the oil back into the reservoir 13,000 feet below the sea floor in what is known as a "bullhead kill." Each gallon of drilling mud weighs 13.2 pounds. A gallon of oil weighs about seven pounds.
If the static kill works, BP will still complete its relief well to seal the well bore from the bottom as well. The relief well is almost complete, and a bottom kill process will probably start in mid-August.

A longer term question is what will happen to the marshes that have been coated with oil.
The oil physically smothers the surface plants, then penetrates deeply into the marsh soil. Plants may die, but the roots can still hold the soil together. If those are damaged too, erosion occurs.

When the roots wash away, the marshes turn to open water, said Mark LaSalle, executive director of the Pascagoula River Audubon Center.

Once a marsh is coated, officials have several options, he said. They can burn the plants, use low-pressure flushing, cut back vegetation or use biomedical remediation. He's not a fan of any of those options because they can do more damage than the oil.

Doing nothing, he said, may actually be the best solution. "Any kind of physical action in marshes is ill advised," he said.
The future state of the marshes is not just an aesthetic concern since they provide a breeding ground for birds and other animals and protect inland areas from the worst effects of storms.