Researchers trying to quantify damage; BP still thinks plan can work

ROBERT, La. (AP) - Researchers are trying to work quickly to chart the effects of the undersea oil spill in the Gulf of Mexico. Scientists say they're concerned about three or four large plumes of undersea oil. They stretch from just beneath the surface of the sea to more than 4,000 feet deep.

At least one of the plumes is 10 miles long and a mile wide. Researchers are also testing whether the subsea oil is depleting oxygen levels in the water. That could harm plankton and other tiny creatures that serve as food for a wide variety of sea critters. One researcher says, in some areas, the oxygen levels are down by 30 percent and it could get worse.

Because of the depth of the ruptured well, scientists say there are many unknowns since the situation hasn't been seen before. Meanwhile, BP engineers are still trying to insert a 6-inch tube with a stopper into the larger, ruptured pipe gushing oil into the Gulf of Mexico. They hit a snag when a piece of equipment required adjustment, but BP says its still confident it can capture much of the leaking oil.

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