Final Deepwater Horizon Flow Rate Estimate Is Likely Too Low, Which Benefits BP
Over the past few months, I've encouraged anyone with any interest at all in the amount of oil that gushed forth from the Deepwater Horizon well into the Gulf of Mexico to check in regularly with Sarabeth Guthberg who, at 1115.org, has been keeping a close eye on a lot of fast-moving numbers -- the estimates from the Flow Rate Technical Group, competing numbers from other scientific authorities -- and the many ways in which BP worked to undermine the measurement effort. Well, the well is now capped, so what's Guthberg's verdict?
This is an unmitigated success for BP. Not so much because they have apparently managed to seal the well for good (though additional cement may also be poured in from the bottom, through the relief well that is nearing completion), but because they managed to do so without ever letting the flow of oil from the blown well be metered.
This is, indeed, great news for BP, because it's the oil flow estimate that will be used to determine the fines that will be levied against BP for destroying the Gulf Coast region. An accurate measurement is "the last thing BP wants".
So the fines will be based on the work of the Flow Rate Technical Group's final estimation. Guthberg pulls the relevant figure from the August 2nd Washington Post:
The blown-out well in the Gulf of Mexico gushed 12 times faster than the government and BP estimated in the early weeks of the crisis and has spilled a whopping 4.9 million barrels, or 205.8 million gallons, according to a more detailed analysis announced late Monday.
BP's Macondo well spewed 62,000 barrels of oil a day initially, and as the reservoir gradually depleted itself, the flow eased to 53,000 barrels a day until the well was finally capped and sealed July 15, according to scientists in the Flow Rate Technical Group, supervised by the U.S. Geological Survey and the U.S. Department of Energy.
Guthberg adds, "Since 800,000 barrels of oil were captured by BP without ever spilling into the Gulf, the fine will be computed on 4.1 million barrels." Skip to the end, and we have a fine of $4.5 billion if BP is found to have "acted with negligence" and $17.6 billion if BP is found to have "acted with gross negligence."
But let's pay very close attention to the numbers that will underpin these fines. In the case of the Flow Rate Technical Group, we're talking about "62,000 barrels of oil a day initially," and then, "the flow eased to 53,000 barrels a day." These are large, plausible numbers. But I think back to a conversation between National Incident Commander Thad Allen and Fox News Sunday's Chris Wallace:
WALLACE: Let's start with the report from the head of BP this morning that the containment well, the containment cap on the well is capturing 10,000 barrels of oil a day. Is that true?
ALLEN: That's true. They increased it to 10,000 over 6,000 the day before.
WALLACE: What percentage of the spill does it represent? Do you agree with the head of BP once they adjust the cap, they're going to be able to capture 90% of the spill?
ALLEN: It remains to be seen. I would establish that as a goal. We need to verify what is going on there. They need to slowly close the vents and optimize the amount of oil in production and we'll know for sure.
WALLACE: 10,000 barrels currently, what does it represent as percentage of the spill?
ALLEN: We estimate low end 12,000 barrels a day, to high 19,000 to 25,000 barrels a day. We have a way to catch up to the flow.
WALLACE: You're saying it could be 80% to 40%?
ALLEN: These are rough estimates. One thing production allows us to do is get a handle on the flow measuring the production.
Wallace more or less caught the hedge-within-a-hedge that Allen was offering with his whole "low end 12,000 barrels a day, to high 19,000 to 25,000 barrels a day." But now that we know that the estimates were much, much higher, these statements need to be revisited. And that's just a small matter, compared to Allen's contention that "production allow[ed] us to... get a handle on the flow measuring the production." When, exactly, did anyone "get a handle on the flow?" At the time Thad Allen was confidently discussing having a "handle on the flow," the estimates were far short of where they are now -- low end 53,000/high end 62,000.
Is there a scientific basis to doubt the current estimates? As it turns out, yes. Let me pass this over to NPR, circa May 14th:
BP has said repeatedly that there is no reliable way to measure the oil spill in the Gulf of Mexico by looking at the oil gushing out of the pipe. But scientists say there are actually many proven techniques for doing just that.
Steven Wereley, an associate professor of mechanical engineering at Purdue University, analyzed videotape of the seafloor gusher using a technique called particle image velocimetry.
A computer program simply tracks particles and calculates how fast they are moving. Wereley put the BP video of the gusher into his computer. He made a few simple calculations and came up with an astonishing value for the rate of the oil spill: 70,000 barrels a day -- much higher than the official estimate of 5,000 barrels a day.
The method is accurate to a degree of plus or minus 20 percent.
Given that uncertainty, the amount of material spewing from the pipe could range from 56,000 barrels to 84,000 barrels a day. It is important to note that it's not all oil. The short video BP released starts out with a shot of methane, but at the end it seems to be mostly oil.
"There's potentially some fluctuation back and forth between methane and oil," Wereley said.
But assuming that the lion's share of the material coming out of the pipe is oil, Wereley's calculations show that the official estimates are too low.
So, there's credible reason to believe that the flow of oil exceeded the sometimes-53,000, sometimes-62,000 barrels-a-day estimate from the Flow Rate Technical Group. And of course, one can just as easily argue that the FRTG's estimates are the correct ones. The point is, we'll never know for sure, and the reason we'll never know for sure is that BP made damn sure that this would be the case. Back to Guthberg:
The Flow Rate Technical Group's 4.9 million barrel estimate was reported just before the static kill was initiated. At that point, BP could still have allowed 100% of the oil spilling from the well to be collected, yielding a precise measurement of how much oil was actually spilling now. This, in turn, would have led to a more accurate measurement of the total oil that was spilled.
The fact that BP didn't do this clearly suggests that the company is confident that the FRTG numbers represent an underestimate, that BP has managed to get away with something here.
Huge Triumph for BP [1115.org]