NEW ORLEANS - BP finally choked off the flow of oil into the Gulf of Mexico on Thursday -- 85 days and up to 184 million gallons after the crisis unfolded -- then began a tense 48 hours of watching to see whether the capped-off well would hold or blow a new leak.
To the relief of millions of people along the Gulf Coast, the big, billowing brown cloud of crude at the bottom of the sea disappeared from the underwater video feed for the first time since the disaster began in April, as BP closed the last of three openings in the 75-ton cap lowered onto the well earlier this week.
But the company stopped far short of declaring victory over the biggest offshore oil spill in U.S. history and one of the nation's worst environmental disasters, a catastrophe that has killed wildlife and threatened the livelihoods of fishermen, restaurateurs, and oil industry workers from Texas to Florida.
Now begins a waiting period during which engineers will monitor pressure gauges and watch for signs of leaks elsewhere in the well. The biggest risk: Pressure from the oil gushing out of the ground could fracture the well and make the leak even worse.
"For the people living on the Gulf, I'm certainly not going to guess their emotions," BP vice president Kent Wells said. "I hope they're encouraged there's no oil going into the Gulf of Mexico. But we have to be careful. Depending on what the test shows us, we may need to open this well back up."
The stoppage came 85 days, 16 hours and 25 minutes after the first report April 20 of an explosion on the Deepwater Horizon oil rig that killed 11 workers and triggered the spill.
Between 93.5 million and 184.3 million have already spilled into the Gulf, according to federal estimates.
See some of the dramatic oil spill photos from this month: