WASHINGTON — After more than a month of concurring with BP's estimate that only 5,000 barrels of oil — 210,000 gallons — was spewing into the Gulf of Mexico from a runaway well, the Obama administration acknowledged Thursday that the real amount is at least double that and perhaps much more.
Three groups of researchers, assembled by the government after independent observers viewing BP video of the leaking well openly disputed the 5,000-barrel figure, reached similar conclusions that the well was spewing 12,000 to 25,000 barrels a day — 504,000 to 1.05 million gallons a day.
Another group is still making observations and is expected to report in coming weeks, Marcia McNutt, the head of the U.S. Geological Survey, said.
The new estimates would make the Deepwater Horzion spill by far the largest in U.S. history, eclipsing the 11 million gallons spilled in Alaska by the grounding of the Exxon Valdez tanker. Using the lower of the new estiamtes, the still spewing well has already dumped at least 18.6 million gallons into the Gulf.
Environmentalists responded in a fury. "It's as if two Exxon Valdez tankers have already run aground and more are on the way if they don't get this hole plugged," warned Jeremy Symons, senior vice president of the National Wildlife Federation. "Now we know the true scale of the monster we are fighting in the Gulf. BP has unleashed an unstoppable force of appalling proportions."
More possible bad news came from the University of South Florida College of Marine Science in St. Petersburg, which said a research vessel in the Gulf of Mexico had detected a disturbing find: A massive new plume in the deep recesses of the gulf spreading northeast toward the continental shelf. More tests would determine if it was contamination from the oil spill heading in a new direction -- toward Mobile Bay, Ala.
A secondary plume, uncovered by the college's Weatherbird II, "could eventually become a threat to marine life and habitats nonetheless."
McNutt called the numbers "still preliminary based on new methodologies being employed to understand a highly dynamic and complex situation." She said scientists are still getting new data and "will continue to refine and update" the estimates.
She called measuring the oil flow "extremely challenging, given the environment, unique nature of the flow, limited visibilty and lack of direct human access."
According to McNutt, one team based its estimate on the amount of oil observed on the surface of the Gulf of Mexico on May 17 — between 130,000 and 270,000 barrels — and a similar amount that had been "burned, skimmed, dispersed or evaporated."
Based on that observation, the team estimated that between 12,000 to 19,0000 barrels per day had escaped the well.
A second team basing its estimate on watching BP videos of the leak said the daily flow was between 12,000 to 25,000 barrels a day.
A third team came up with a 12,000 estimate, as well
"Three methodolgoies suggest a lower bound is 12,000 and 2 methodolgoies suggest it could be as much as 19,000 per day.
McNutt said the teams pulled "all nighters" to come up with the estimates.
McNutt said an accurate appraisal opf the leak hadn't been possible until the last two weeks, when a tube inserted into one of the leaking pipes began drawing oil and gas to the surface. That allowed researchers to determine that 75 percent of what they were seeing on video spewing from the broken pipe was natural gas.
"That’s why we're now now getting better estimates, because we can correct for the gas phase," she said. Asked whether the spill has eclipsed the Exxon Valdez, McNutt demurred. "This is obviously a very, very significant environmental disaster and I think with the numbers I've given you, you can do the math."