NEW ORLEANS — A new report by the federal offshore safety agency concludes that incorrect weather forecasts and a poor decision to try to ride out a storm caused $5.7 million in damage to a Gulf of Mexico drillship during Hurricane Zeta in October 2020.
The Interior Department’s Bureau of Safety and Environmental Enforcement released its accident investigation report for the damage sustained by the Deepwater Asgard drillship on Oct. 28. The report came out several months after similar reports for incidents that happened more recently.
The drillship owner, Transocean, decided to keep the rig latched onto a well with a milelong riser pipe in the Gulf of Mexico, rather than pulling the pipe up and moving to safety.
The government report said weather forecasts incorrectly predicted the storm would be a Category 1 hurricane and go east of the well location. Instead, it went directly over the well and registered wind gusts equivalent to a Category 4. The report also found “human error” because Transocean decided to “ride out the storm.”
The crew ended up having to disconnect from the well in the midst of the storm, as the drillship was being knocked off the well site. That caused the riser pipe to bend dangerously. The rig successfully disconnected, but the pipe was dragged into shallower water, damaging a piece of equipment at the bottom and the pipe where it collided with the hull of the drillship.
The government report says the well owner, Beacon Offshore Energy, and Transocean have agreed to make changes to avoid the situation in the future.
Beacon “will recommend to its rig contractor that they should secure the well, displace the riser to seawater, disconnect from the well and pull a specified length of riser from the water column, and proceed to a secure location.”
The report also says “Transocean will revise their Extreme Weather Evacuation Plan (EWEP) to ensure they meet all internal and external requirements regarding operational limits.”
WWL-TV reported on the Deepwater Asgard incident last month, including a lawsuit filed by crewmember Christopher Pleasant. Pleasant was also on the Deepwater Horizon when it exploded in 2010.
Pleasant testified after that disaster that he tried to initiate the emergency disconnect process and was initially overruled by the Deepwater Horizon’s captain. With the Deepwater Asgard, Pleasant alleges the captain ordered the crew to stop the unlatch process the day before the storm hit.
“At the 4:00 p.m. phone call, Transocean and Beacon ordered the vessel to stay latched despite Hurricane Zeta headed directly toward them,” Pleasant’s lawsuit states.
Pleasant and other crewmembers “strongly disagreed with the decision to stay latched but had no other options but to obey orders,” the lawsuit continues.
The lawsuit alleges that the vessel was knocked so far off location because it lost power to the engines that keep it stabilized on the surface of the sea. But only one thruster lost power temporarily and the government report states the vessel was forced nearly two miles off its location despite the thrusters working at 100 percent.
The government report doesn’t mention Pleasant’s specific claims and doesn’t comment on any internal debate about the decision to stay latched on. It does say that Beacon agreed to require its drilling contractors to assess equipment called “tensioners” that help maintain tension in the riser pipe. Pleasant alleges in the lawsuit that the tensioners failed in Hurricane Zeta and were supposed to have been replaced earlier in the year but were not.
