The Fifth U.S. Circuit Court of Appeals said Thursday the Chemical Safety and Hazard Investigation Board (CSB) can investigate Transocean’s role in the 2010 Deepwater Horizon accident.
The Deepwater Horizon semi-submersible drilling rig was owned by Switzerland-based Transocean.
In June, the CSB published a report citing multiple failures and inadequate testing of the Deepwater Horzion’s blowout preventer.
The report said the failures factored into the explosion that killed 11 crewmen and caused an oil spill.
The CSB assigned fault for the failures to BP and Transocean.
BP was the operator of the rig when the accident happened at the Macondo Prospect oil field about 40 miles southeast of Louisiana in the Gulf of Mexico.
The ruling affirms the CSB’s argument that the Deepwater Horizon falls under its jurisdiction because it is a “stationary source.”
Transocean argued that the rig was mobile and did not qualify as a stationary source.
The court ruled the rig qualified as a stationary source under the Clean Water Act.
“In this case, the Deepwater Horizon was deployed to the Macondo well site in February 2010 and had remained in place at the site for approximately two months,” Judge Thomas Reavley said in an opinion joined by Judge James Graves.
Transocean has not commented on the ruling.