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By Stephanie Grace
NEW ORLEANS, March 4 (Reuters) - BP's own investigation ofthe 2010 Gulf of Mexico spill ignored a phone call between BPsupervisors about a critical pressure test that wasmisinterpreted with deadly consequences, a lawyer for rig ownerTransocean Ltd contended in aggressive questioning onMonday.
As a civil trial that will determine blame for the disasterentered its second week, Transocean lawyer Brad Brian pushedBP's global head of safety and operational risk on why thereport did not mention that call even though investigatorsmentioned it in their notes.
The report by BP Plc placed most of the blame for theexplosion and spill on Transocean, whose Deepwater Horizon rig,under contract with BP, had been drilling a mile-deep well whena surge of gas caused a blowout that killed 11 workers.
"I think my team's thinking was ... it was mentioned, itwasn't in the form of consulting about it," replied Mark Bly,the BP executive who headed the company's investigation.
The U.S. Justice Department, Gulf Coast states affected bythe spill, and other plaintiffs - all of whom are suing BP,Transocean and other companies - argue that BP put profits oversafety in the drilling job, which was over-budget and overdue.
Lawyers for the plaintiffs have argued that had well siteleader Don Vidrine heeded concerns of onshore senior drillingengineer Mark Hafle about that pressure test and stopped theoperation, the disaster at the Macondo well could have beenaverted.
London-based BP has acknowledged that engineersmisinterpreted the results of the test, but holds both itselfand Transocean responsible for that.
Brian also questioned whether Bly and his investigative teamlooked into whether BP's decisions were driven by saving timeand money. "We didn't look at that specific question," Bly said.
The trial has now entered its second week before U.S.District Judge Carl Barbier in the first of three phases. Thefirst phase focuses on allocation of blame among the companiesinvolved.
Later on Monday, Andrew Hurst, a geology and petroleumgeology professor at the University of Aberdeen, Scotland,testified on behalf of the plaintiffs that rock layers whereMacondo was drilled are particularly fragile because the area isthe site of the second-largest underwater landslide in the worldand was the site of an undersea earthquake in 2006.
He said the drilling operation could have left the rock sofragile that cement pumped into it could not bind to the rock asrequired.
"My opinion is that formation around the bore holedisintegrated," Hurst testified. "I can't see how anything elsecould have happened."
Under cross examination, BP attorney Matt Regan stressedthat Hurst's observations about thermal conditions and pressurewhere BP drilled would apply to the vast majority of such sites,and that many in the industry do not follow his prescribedprocedures.
He also asked Hurst whether his conclusions were based on"Macondo specific data" or general observations. Hurst respondedthat he based his opinions on science, conceding that he did nottry to "form a prognosis" for the Macondo well.
The case is In re: Oil Spill by the Oil Rig "DeepwaterHorizon" in the Gulf of Mexico, on April 20, 2010, No.10-md-02179, in the U.S. District Court, Eastern District ofLouisiana.
