Myriad agencies have investigated BP's
The U.S. Chemical Safety Board, which investigates chemical explosions in the same manner the National Transportation Safety Board investigates airplane crashes, launched its first offshore investigation shortly after the 2010 explosion killed 11 workers and allowed more than 4 million barrels of crude to foul the gulf.
However, Transocean Ltd
The magnitude may be unique, but there certainly have been ambient releases offshore, Transocean attorney David Baay said at a hearing before U.S. District Judge Lee Rosenthal in Houston on Thursday.
Assistant U.S. Attorney Adam Goldman said the CSB has jurisdiction because its probe focuses on the blowout and explosion rather than the spill.
The reason we're here is not because there was an oil spill. The reason we're here is that there was a loss of 11 lives, Goldman responded.
Rosenthal was expected to rule at a later date.
Don Holmstrom, the CSB's chief investigator in the case, told Reuters before the hearing that other companies involved with the Macondo well that blew out, including BP, Halliburton,
Other spill investigations completed last year include a probe by the U.S. Coast Guard and the U.S. Interior Department, which put most of the blame on BP for the disaster.
The CSB, created in 1990 and funded since 1998, has investigated chemical spills and refinery explosions, including the 2005 blast at BP's Texas City, Texas refinery that killed 15 people. The agency has no enforcement powers, but can recommend improvements in safety practices and regulations.
(Reporting by Kristen Hays; Editing by Tim Dobbyn)