The amount of oil spilled by the Macondo well in 2010 was more than 1.7million barrels less than the total claimed by US authorities, a leading industry expert has said.
Martin Blunt, assistant petroleum engineering professor at Imperial College London, said his estimate for the amount of oil spilled into the Gulf of Mexico was 3.26million – significantly less the 5million experts for the US government say was spilled.
Professor Blunt was giving evidence for BP at the second phase of the trial into the 2010 Gulf of Mexico disaster, which saw 11 people killed when a well blowout sank the Deepwater Horizon platform.
US District Judge Carl Barbier has been hearing evidence in the second phase about the amount of oil spilled – a number which will determine the fine BP must face for the disaster.
Professor Blunt told the court his measurements took into account the geology of the area around the well, using a coiled spring toy to demonstrate the waves of pressure that built up in the well before it exploded on April 20 2010.
He told the court he had rejected the spill-counting methods used by expert witnesses with the US government, as they had not taken into account the geology of the oil reservoir or the area around the well which had an affect on how much flowed out. His conclusions were based on survey data from BP from before the well was drilled and during the disaster itself.
US Attorney Scott Cernich, representing the plaintiffs – who include the US Government and states affected by the disaster, told the court that another petroleum engineer from Professor Blunt’s college had disagreed with his findings, and questioned the amount of oil he said had flowed.
Professor Blunt told the court that the well flow rate on the day it was capped was around 45,000bod, while earlier this week a witness for the plaintiffs testified the rate had been 54,000bod based on measurements from the well.
Under Blunt’s figures, BP would be liable for 2.45million barrels of oil spilled into the Gulf, as Judge Carl Barbier – who is hearing the trial in New Orleans – has already ruled out the inclusion of the 810,000 barrels which were picked up by oil collection systems on the surface.
The trial entered recess until next Tuesday.