The National Academy of Engineering released its independent report Wednesday on what went wrong on the Deepwater Horizon oil rig, repeating well-worn findings that BP failed to assess risks and chose less expensive actions that hastened explosions that killed 11 workers and created the worst oil spill in U.S. history.
The independent scientists’ report, requested by Interior Secretary Ken Salazar to provide a separate perspective amid several governmental inquiries, offers little new information. In fact, it repeats findings presented in previous newspaper reports that focused on key human errors.
But the National Academies report leaves open-ended the question of exactly which errors might have precipitated the explosions. Instead, it takes a much more skeptical view of the insistence by BP and other oil and gas companies that they are guided by a “culture of safety” in the deepwater Gulf of Mexico.
The report says, “The failures and missed indications of hazard were not isolated events …. Numerous decisions to proceed … despite indications of hazard … suggest an insufficient consideration of risk and a lack of operating discipline.”
It derides BP engineers for insisting at several Marine Board investigative hearings that “safety was never compromised,” saying that suggests they never really recognized the risks they were facing. It also notes that BP well site leader John Guide was responsible for both the costs and schedule of rig work and that his decisions often led to both cost savings and increased risks.
The report also goes further than others in questioning the knowledge of rig workers and supervisors as they tried and failed to correctly interpret key tests that should have warned them of impending disaster.
The report’s biggest contribution of new information deals with a possible break in the bottom of the well during the cementing procedure. The scientists’ panel found that the rig needed to use a lighter drilling mud at one section three miles below the sea floor because heavier mud apparently caused the rock formation to cave in accidentally.
Later tests showed materials pumped into the well were getting lost down in the hole, a sure sign that something was wrong. The scientists say that should have been a warning to the rig crew and engineers in Houston that the well wasn’t properly closed.
The report also puts much blame at the feet of BP and Transocean personnel for misinterpreting a negative-pressure test that should have informed them of a leak in the well. The scientists seemed incredulous that BP rig leaders accepted an explanation from Transocean that high pressure readings in the well were due to a poorly understood phenomenon that may or may not exist, called the “bladder effect.” Then, the report questions how the confusing test results were never reviewed by BP engineers on shore, people who theoretically would have had better knowledge to assess the situation.
The report is an interim report; it was released by a committee of the National Academy of Engineering and the National Research Council. The committee says a final report in June will address ways the industry can avoid similar deepwater drilling accidents in the future.
A recent report from the national Oil Spill Commission struck a more favorable tone for BP, accepting the company’s internal investigation report as “90 percent” accurate and shifting some of the blame onto BP’s contractors, such as cementing specialist Halliburton. But the National Academy’s report Wednesday is decidedly more critical of BP, listing failures that were squarely in the well-owner’s purview:
— Changing key supervisors days before critical procedures began;
— Combining difficult cementing steps at the end of the process;
— Using a single central tube to line the whole length of the well, rather than doing it in shorter segments with more barriers against natural gas seeping in;
— Ignoring models that called for more safety devices called centralizers;
— Not running various tests that could have warned the crew of problems; and
— Removing heavy drilling mud before locking down the well’s components.
The National Academy report also criticizes federal regulators for not identifying the high-risk methods employed on the Deepwater Horizon.
