Chu defends federal estimate of Macondo oil flow rate

Washington (Platts)--7Dec2010/633 pm EST/2333 GMT

US Energy Secretary Steven Chu on Tuesday defended the calculations he and others in the federal government made in estimating how much oil flowed from Macondo wellhead in the Gulf of Mexico earlier in 2010, after indications surfaced last week that BP may dispute those estimates in federal court.

Flow-rate estimates will be critical for determining how much the federal government will levy in fines against the company for the leak that followed the April 20 blast aboard the Deepwater Horizon rig, which resulted in one of the worst oil spills in history.

On December 3, Priya Aiyar, deputy chief counsel for the presidential National Oil Spill Commission, said she was told by BP that the company intended to argue in court that the amount of oil spewing from the wellhead was 20% to 50% below government estimates.

Chu -- a Nobel Prize-winning physicist -- led the government scientific team responding to the spill, and personally oversaw many of the calculations used to estimate the flow rate.

"We calculated this in many, many different ways. We went [through] half a dozen different ways of going and getting at it, many of them giving us more or less the same numbers," Chu said in an interview with the Platts Energy Week television program.

"We take all the information we have. Now, if it turns out that a particular number that we were given turns out to be wrong, then one can examine that," Chu said. "But given the information we were given by BP, given the information on the pressure gauges that we had -- we had numerous pressure gauges -- given the more detailed calculations, we are pretty confident that the number was a reasonably good number."

Under the Oil Pollution Act and the Clean Water Act, the federal government can levy fines against BP to the tune of $32,000 per day or $1,100/barrel of oil that was spilled. If the government determines the spill was caused by gross negligence or willful misconduct, the fines could rise to $4,300/b.

The government's Flow Rate Technical Group has estimated that between 53,000 b/d and 62,000 b/d flowed from the well from April 20 to the time it was capped in July. That amounts to 4.9 million barrels over 87 days.

Platts Energy Week airs at 8 a.m. EST (1300 GMT) on Sundays on WUSA 9 in Washington, and at 7:30 p.m. CST on Mondays on KHOU 11.2 (Comcast 310) in Houston. The program is also available on the web at www.plattsenergyweektv.com.

--Derek Sands, derek_sands@platts.com

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