HOUSTON -- Four years after the deadly Macondo offshore well blowout and explosion, oil drilling in the Gulf of Mexico remains unsafe despite scores of reform efforts, an independent federal investigative team warns in a report released here today.
The accident at the Deepwater Horizon rig that killed 11 workers and seriously injured 17 sparked a wide-reaching reform initiative for offshore drilling regulations with authorities dissolving one federal agency and creating three new ones in its place. And a chastened industry responded by creating two offshore-blowout response teams and promising to double down on safety and assurance systems.
But in a new investigation of the 2010 oil spill that could spark fresh debate over offshore oil and gas exploration in the Gulf of Mexico and beyond, the U.S. Chemical Safety and Hazard Investigation Board concludes that all these changes aren't enough.
Deepwater drilling remains a risky proposition despite the new safety regulations, including the Bureau of Safety and Environmental Enforcement's (BSEE) requirement for all offshore drillers to have in place independently audited safety and environmental management systems, or SEMS, says the panel that probes major chemical accidents.
BSEE is one of two agencies formed from the pieces of the now-defunct Minerals Management Service. The Bureau of Ocean Energy Management now handles lease sales and permitting, while the Office of Natural Resources Revenue collects royalty payments.
BSEE's response in the wake of one of the worst environmental disasters in U.S. history was a bid to strengthen the safety culture in the offshore drilling industry by imposing strict new SEMS guidelines and enhancing safety systems and inspections.
Major oil and gas companies responded by founding the Marine Well Containment Co. and the Helix Well Containment Group to pre-mobilize assets for offshore leak response, including capping stacks and response vessels. And three major Texas universities collaborated to form the Ocean Energy Safety Institute using a federal seed grant.
The Chemical Safety Board's findings largely overlook those efforts and focus attention on what it considers the most important element in accident prevention: the blowout preventer -- the final device that stands between a loss of well control and a catastrophic offshore blowout.
These key pieces of safety-critical equipment the industry relies on as the final backstop to preventing blowouts still contain dangerous design flaws, CSB found.
In a two-volume report on its investigation, CSB offers a new theory on why the Transocean Ltd. rig's blowout preventer failed. CSB investigators believe the drilling pipe in the well at the time of the loss of well control "buckled due to a phenomenon called effective compression" and prevented the blowout preventer (BOP) from effectively sealing the well.
CSB issued its findings at a press conference in downtown Houston today and will discuss its investigation at a public gathering this afternoon.
Investigation team leader Cheryl MacKenzie said that the buckling of drill pipe could lead operations to conclude that a BOP had succeeded in plugging a well when in fact it had not. She added that her team’s findings differ from other investigations in that the CSB concludes that the blind shear ram in the BOP was activated during the disaster, but the pipe deformation prevented it from working properly. Other investigations concluded that the critical BOP component was activated several days after the spill began.
Faulty wiring in the BOP control system at Macondo further highlights the lack of serious attention to these safety systems inherent during the drilling operations, CSB notes in its report.
Bad wiring in the controls that went undetected by inspectors could have led to disaster, but the nature of the fault allowed the system to work regardless of the flaw. Ironically the mis-wired controls subsequently caused a battery failure in part of the system, permitting the Deepwater Horizon's last-ditch safety system to activate the shears and sealing anyway, despite the misalignment of the electronics within the system.
The board found that a mis-wiring of a solenoid valve in one of two redundant controls for the Deepwater Horizon BOP's blind shear ram (BSR) used to cut and seal pipe led to controls opposing each other rather than working together. But at the same time, the faulty wiring drained battery power from one. Had that not been the case, the BSR would have also failed, further highlighting mechanical errors that were undetected despite repeated checks of the entire BOP system used by the Deepwater Horizon's crew.
The BSR was activated. Nevertheless, the buckled pipe prevented the BOP from doing its job, leaving the well exposed and sending 5 million barrels of oil spilling into the Gulf's waters, CSB says.
And it could happen again, investigators warn.
"Had both coils been successfully energized on the day of the incident, the solenoid valve would have remained closed and unable to initiate closure of the BSR," investigators write. "However, a drained battery likely rendered one of these coils inoperable. This would have allowed the other coil to activate alone and initiate closure of the BSR, but buckled off-center drillpipe in the BOP prohibited the BSR from fully closing and sealing the well."
CSB argues that this design flaw -- the inability of BOPs to seal a well due to buckled or misaligned drill pipe -- likely exists in other offshore operations' BOPs and could be going undetected in offshore drilling and oil and gas production throughout the Gulf of Mexico.
CSB investigators found another oversight: The BSR in the Deepwater Horizon's BOP wasn't designed to cut and seal the drilling pipe used for almost all of the Macondo well's development, save for the very end of the process when the accident occurred.
Macondo's blowout happened while the crew was attempting to temporarily plug and abandon the well, paving the way for a production platform to later come in and complete it.
Holes in federal safety net
Gaps in federal regulation of offshore drilling also remain, CSB argues.
Though it acknowledges positive steps that have been taken, CSB criticizes the SEMS regulations for lacking "an explicit focus on major accident events." Investigators also conclude that the SEMS are lacking for not requiring the industry to demonstrate that the mechanical barriers put in place to prevent major accidents, like BOPs, are "effectively implemented to a targeted risk reduction level."
Rules to test particular control systems on BOPs did not exist at the time of the Macondo disaster, but BSEE now requires such testing and safety checks. Despite these new regulations, "deficiencies identified during the failure analysis of the Deepwater Horizon BOP could still remain undetected in BOPs currently being deployed to wellheads," CSB investigators say.
BSEE is in the midst of updating its rules and procedures governing blowout preventer technology. The agency had planned on issuing a first set of proposed changes to the regulations by the end of last year, but the process has been delayed by several months. BSEE now says the proposed rules will be posted sometime this year.
BP's Macondo well was plagued with problems throughout the time the Deepwater Horizon was drilling the well. The accident happened as the crew was moving to temporarily abandon the well, removing fluids from the well bore between the surface and a cement plug deep in the well put in place to keep hydrocarbons from escaping. The crew would then have cemented in a surface plug before disconnecting the rig from the well.
Instead, the first plug was cemented poorly, and hydrocarbons flowed out of the reservoir as the drilling fluid was being removed. Contractors on the Deepwater Horizon failed to detect this until it was too late. Crude oil violently shot out of the well and spilled onto the floor of the rig. The crew wasn't able to divert the flow overboard.
The oil subsequently ignited, causing the rig to explode. CSB dedicated its report to the 11 men who died in the accident. CSB plans to issue volumes 3 and 4 of its findings at a later date.
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