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September 8, 2010

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Rig explosion caused by “complex sequence of failures by multiple parties”

The actions of “multiple companies and work teams” contributed to the Deepwater Horizon explosion and fire in the Gulf of Mexico earlier this year, a report released by BP has concluded.

Eleven workers were killed and 17 injured on 20 April when hydrocarbons escaped from the Macondo well on to the Transocean-owned Deepwater Horizon oil rig. The fire, which was fuelled by the hydrocarbons, continued for 36 hours, while oil continued to spew into the Gulf for 87 days, causing major environmental damage.

BP’s report – based on a four-month investigation led by its head of safety and operations, Mark Bly, and conducted independently by a team of more than 50 technical and other specialists – found that the incident arose from “a complex and interlinked series of mechanical failures, human judgements, engineering design, operational implementation, and team interfaces”.

The investigation revealed that:
• cement barriers at the bottom of the well failed to contain hydrocarbons within the reservoir, allowing gas and liquids to flow up the production casing;
• a negative pressure test was accepted despite no verification having been made as to the integrity of the well;
• Transocean rig crew failed to react quickly enough when faced with the influx of hydrocarbons into the well;
• upon reaching the rig, the well-flow was routed to a mud-gas separator, which caused gas to be vented directly on to the rig instead of overboard;
• the flow of gas into the engine rooms through the ventilation system created a potential for ignition; and
• the rig’s blow-out preventer on the sea bed should have activated automatically to seal the well, but failed to operate.

The report makes 25 recommendations to prevent a recurrence of such an incident, covering the use of blow-out preventers, well control, well-integrity pressure testing, emergency systems, cement testing, rig audits, and personnel competence.

Among these suggestions, it proposes the enhancement of Drilling and Completions (D&C) competency programmes to improve personnel’s operational and leadership skills; and calls for an advanced and mandatory deepwater well-control training programme for all BP and drilling contractor staff who are directly involved in deepwater operations.

Recommendations aimed at improving process-safety management include the establishment of D&C leading and lagging indicators for well integrity, well control, and safety-critical equipment; and a requirement on drilling contractors to implement an auditable integrity-monitoring system in relation to well-control equipment.

Commenting on the report, BP’s outgoing chief executive, Tony Hayward, said: “The investigation report provides critical new information on the causes of this terrible accident. It is evident that a series of complex events, rather than a single mistake or failure, led to the tragedy. Multiple parties, including BP, Halliburton [which performed several services on the rig, including cementing] and Transocean, were involved.”

Hayward’s replacement, Bob Dudley, added: “We are determined to learn the lessons for the future and we will be undertaking a broad-scale review to further improve the safety of our operations. We will invest whatever it takes to achieve that. It will be incumbent on everyone at BP to embrace and implement the changes necessary to ensure that a tragedy like this can never happen again.”

The publication of the report comes the day after a committee of MPs grilled UK oil and gas industry representatives on whether a similar incident could occur in British waters. The hearing in front of the Energy and Climate Change Select Committee saw the UK managing director of Transocean, Paul King, refute accusations that safety representatives had been bullied and intimidated for raising safety concerns.

Mr King described any incidents of this nature, which are highlighted in an unpublished report by the HSE, as “isolated” cases. He added: “I would not let my son work for this company if I didn’t believe it cares deeply about its people. I actually find it quite offensive that people think we take rules for granted.”

Guidelines discouraging the use of the ‘Not Required Back’ (NRB) practice – where an owner of an offshore installation contacts the operative’s contracting employer to tell it the individual is no longer required on that installation – without justification were introduced last year by the industry body Oil & Gas UK.

Asked if Transocean still operates NRB, which it has been claimed sends a strong signal to workers that it might not be in their best interests to raise safety issues, Mr King was insistent. He told the MPs: “If we have a problem with anybody on our rigs who is not performing from a safety perspective or a competency perspective, we would talk with them offshore before they leave the rig to advise them what our thoughts are about their work, and, if it is the case that we find their work unacceptable, why they will not be coming back to the rig.”

Malcolm Webb, Oil & Gas UK’s chief executive, pointed out that a survey on workforce engagement, carried out as part of the HSE’s KP3 report into asset integrity, gave “very high assurance from the workforce that they are free and able to intervene on safety, and without fear of retribution”.

Defending the UK’s regulatory regime, he said: “We have a regime where safety is divided from economic regulation, which is not the case in the US. We have the whole safety-case regime, which obliges the operator and the owners of the vessels to make sure that they’re operating to a standard that reduces the risk of the operation to that which is as low as is reasonably practicable. And we have independent verification of well design and independent verification of safety-critical equipment.”

Following the publication of the BP report, the group’s communications director, Trisha O’Reilly, did however pledge that the findings of the Deepwater Horizon investigation would be studied in detail. She said: “The UK’s safety-case regime obliges the industry to examine its existing arrangements in light of incidents around the world and put into action any consequent improvements that can be made.”

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13 years ago

If safety is expensive try an accident.
Now, BP Profits as a result of safety compromises over the years has gone down the drain to compensation and other expenses. Too poor.

Believe me this kind of accident is preventable. Imagine BOP could fail? !!!. It was just there as a statu, what a shame. With all the NEBOSH and OSHA, Safety is all about attitude.


13 years ago

I told all my family when this first happened that the standard of maintenence on BOP’s in many areas outside UK waters was low in my opinion. I have been involved in drilling operations many years and there are some excellent BOP Techs out there and there are also some poor ones who “save” money to prove they are good? It is a very demanding position and requires someone who realy is proud of his position. It is one of the most important positions on any drilling operation.

13 years ago

Safety is not just a cost to a business but a required “evil”!

Directors moan about the cost, managers moan about trying to implement it and operatives moan about trying to get the job done under it. But this accident highlights the requirement to have a robust H&S and operation (intergrated) managment system in place that all parties can understand and operate under.

Scott R