The risk of an oil spill on BP's Gulf of Mexico rig had been clearly foreseeable on its monitoring systems, but those systems lacked proper alarms to alert tired engineers.
That is a final verdict of the US Oil Spill Commission, tasked by president Barack Obama with investigating the disaster. In its report published today, it blamed serious errors and cost-cutting decisions by BP and lead partners Transocean and Halliburton, and called for an industry and regulatory overhaul to prevent future accidents.
The OSC reiterated that BP, in a bid to save time and money, had turned a blind eye to the results of Halliburton’s OptiCem modelling software which concluded early on in the drill that more support rods were needed to stabilise the well. The well was reportedly costing millions of dollars to run every day, even before drilling completed.
The commission said that thirty minutes before oil started spewing from the well floor, monitoring software systems showed unusual increasing pressure in the drill pipe at a time it had been closed off. "Had someone noticed it, he would have recognised this as a significant anomaly that warranted further investigation before turning the pumps back on," the report said.
The report’s authors expressed exasperation that the key monitoring software - the Halliburton Sperry Sun system and the HiTec system from rig owner Transocean - did not have alarm systems to alert engineers to changing pressure in the well. Engineers, working up to 12 hour days, could miss the signs, it said.
"There is no apparent reason why more sophisticated, automated alarms and algorithms cannot be built into the display system to alert the driller and mud logger when anomalies arise," said the commission.
The OSC insisted it was "no longer acceptable" for oil companies to rely on a system that "requires the right person to be looking at the right data at the right time, and then to understand its significance in spite of simultaneous activities and other monitoring responsibilities".
But it also insisted that there needed to be better management and organisation to make sure that important data on screen is spotted. While the Sperry Sun system presented pressure data on an on-screen pressure graph, the Transocean HiTec software “likely would have been clearer” because it displayed clear numeric values, the OSC said.
Meanwhile, investigations have still not uncovered what happened to the blowout preventer, which sits on the well head and is intended to prevent this type of accident. Forensic examinations on the device are continuing. The OSC suggested a lack of proper maintenance of those automated and manual safety devices may be at fault.
A spokesperson at BP said today that the "emerging consensus" was that the spill "was the result of multiple causes involving multiple parties", expressing "support" for the Commission's efforts to strengthen industry-wide safety practices".
The spokesperson added: "We are committed to working with government officials and other operators and contractors to identify and implement operational and regulatory changes that will enhance safety practices throughout the oil and gas industry."