BP may attempt "top kill" today

(NBC) - A mile beneath the surface, the oil continues its steady stream as preparations continue to try to stop it.

Diagnostic tests will determine when BP finally starts its top kill, forcing drilling mud through the blowout preventer in an attempt to seal the leaking well.

"One of the critical things that's going to happen while they're pumping the mud down is to understand the pressure that's being exerted on the pipe," Oil Spill Incident Commander Admiral Thad Allen said.

The company now says when it does start, the process could take several days.

While BP makes its latest attempt to stop it, along the coast, many fear the catastrophe is just starting.

"It's still coming out of the ground. This oil took a month to get here, but there's a still a month of oil behind it," Myron Fischer of the Louisiana Department of Wildlife said.

Calls continue for the Administration to step in, even as the President announced plans to once again visit the area on Friday.

"They are window dressing. This has been the worst response I have ever seen - the worst attempt at a response," Plaquemines Parish President Billy Nungesser said.

And then there are those without voices - swimming, sitting and struggling through the oil.

"I don't see how he can survive it," said Capt.Clement Santiny.

Surviving it is a challenge shared by so many here now, waiting to see if the latest fix will work and how much worse it will get.

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