The US Coast Guard said Friday that deficiencies in Transocean's safety culture contributed to the sinking of the company's Deepwater Horizon rig after BP's Macondo well blew out in the US Gulf of Mexico one year ago.
These included "poor maintenance" of electrical equipment that may have ignited the explosion; bypassing of gas alarms and automatic shutdown systems that could prevent an explosion; and a "lack of training of personnel" on when and how to shut down engines and disconnect the mobile offshore drilling unit (MODU) from the well to avoid a gas explosion, the Coast Guard said in its report on the circumstances surrounding the explosion, fire and sinking of the Deepwater Horizon rig and the loss of 11 crew members.
"These deficiencies indicate that Transocean's failure to have an effective safety management system and instill a culture that emphasizes and ensures safety contributed to this disaster," the Coast Guard said.
For example, the master, or rig captain, acknowledged that the safety management system training he received consisted of viewing a Power Point presentation and he could not recall the content of that or where to find it, the Coast Guard found.
"The master was not aware that he had authority to activate the Emergency Disconnect System, a critical step to cut off the flow of flammable gases to the MODU, and the official who received gas alarms was unaware of procedures relating to the activation of the emergency shutdown system in response to such alarms, even though shutting down the engines could have averted an explosion," the Coast Guard said.
The master and three crew members jumped 50 feet into the water after they did not have time to launch a fourth lifeboat. All told, 115 people were able to evacuate and survived. The report summarized how confusion and panic ensued as workers entered the first three lifeboats or jumped off the rig. They were picked by a supply vessel.
Also, the rig was classified by its flag-state, the Marshall Islands, as having a dual-command structure with an offshore installation manager in charge when the rig was attached to the well and a master in charge when the vessel was mobile. But, when the explosions began, there was no immediate transfer of authority from one to the other, the Coast Guard said, and the master asked permission from the OIM to activate the emergency disconnect.
"This command confusion at a critical point in the emergency may have impacted the decision to activate the EDS," the report said.
The Coast Guard also found that Transocean had a poor maintenance record that could impact capabilities in firefighting, electrical and watertight integrity systems. Plus, "contrary to the manufacturer's guidelines which called for inspection and certification of the blowout preventer (BOP) every three to five years, Transocean did not arrange to have the Deepwater Horizon BOP recertified for over 10 years."
A report commissioned by the Bureau of Ocean Energy Management, Regulation and Enforcement recently found that the shear rams of the BOP could not cut through buckled drilling pipe.
A Transocean official, reached via email on a quiet Good Friday in the US, did not have any immediate comment on the report.
COAST GUARD EYES TIGHTER STANDARDS FOR FOREIGN-FLAGGED RIGS
The April 20, 2010, Macondo exploratory-well blowout 40 miles offshore Louisiana and subsequent fire destroyed Transocean's Deepwater Horizon drilling rig, killed 11 workers and created the largest marine oil spill in US history. Because the well could not be shut-in and the rig was not disconnected from the well head, hydrocarbons fueled the fire unabated, the Coast Guard said, and the rig sank the morning of April 22, 2010.
On April 20 at around 9:50 p.m. CDT (0250 GMT April 21), an initial explosion rocked the rig as hydrocarbons rising from the well ignited, the Coast Guard recounted. A second explosion struck and a conflagration "burned out of control," it said.
"Although the events leading to the sinking of Deepwater Horizon were set into motion by the failure to prevent a well blowout, the investigation revealed numerous systems deficiencies, and acts and omissions by Transocean and its Deepwater Horizon crew, that had an adverse impact on the ability to prevent or limit the magnitude of the disaster," the Coast Guard said.
Many details in the Coast Guard report came out during a series of public hearings by the joint investigative team comprising the Coast Guard and the BOEM.
The report noted that the rig crew may have been distracted as well the day of the disaster's outbreak.
"The presence of the visiting BP and Transocean executives in the central control room/bridge of Deepwater Horizon immediately prior to the casualty may have diverted the attention of the offshore installation manager and senior toolpusher from the developing well conditions, limited their interactions with the on-watch drilling crew, and led to their failure to follow the emergency evacuation procedures," the Coast Guard said.
The Coast Guard also recommended more scrutiny of foreign-flagged rigs operating in US waters, citing the Deepwater Horizon's flag state, the Republic of the Marshall Islands, as "ineffective." The state delegated inspection activities to "recognized organizations," thereby abdicating its inspection responsibilities.
The joint investigative team recommends that the Coast Guard beef up inspection requirements with several steps, including: coordinating expanded International Safety Management Code examinations of all Transocean vessels that are subject to that and engaged in the US Outer Continental Shelf; work with the Marshall Islands on annual verification of the safety management of the main and North American offices of Transocean; and develop more comprehensive inspection standards for foreign-flagged mobile rigs in the OCS region.
Before BP installed the sealing cap July 15, 2010, Macondo had released an estimated 4.9 million barrels of oil, including 800,000 barrels captured by BP in a variety of collection devices deployed during the crisis phase.
The well was later killed by a relief well intercept and cement job to seal off the reservoir. The US declared the well officially dead on September 19.
