The entry ends with what the negative pressure test taught. This piece follows what was made of it afterwards: four investigations, two corporate guilty pleas, a civil trial, and the cases against the two BP men who had been in the drill shack. It runs from BP’s own report in September 2010 to the last sentence in April 2016, and takes the documents in order.

BP’s report, September 2010

BP’s investigation, led by Mark Bly, reported on 8 September 2010, less than five months after the blowout. Its third key finding was that “the negative-pressure test was accepted although well integrity had not been established.” Its account of the test matched the others in substance: the preventer that did not seal at first; 1,260 pounds bled from the drill pipe with fifteen barrels returned where about 3.5 should have been expected, which “should have indicated to the rig crew a communication flow path with the reservoir through failed barriers”; the shift to the kill line because the permit said so; the drill pipe rising from about 50 to 1,400 between 6:00 and 6:35; the kill line opened, 0.2 barrels, thirty minutes of nothing. On the explanation: “According to witness accounts, the toolpusher proposed that the pressure on the drill pipe was caused by a phenomenon referred to as ‘annular compression’ or ‘bladder effect.’ The toolpusher and driller stated that they had previously observed this phenomenon. After discussing this concept, the rig crew and the well site leaders accepted the explanation. The investigation team could find no evidence that this pressure effect exists.” Its conclusion was that “the lack of flow from what was believed to be an open kill line, coupled with the erroneous explanation for the 1,400 psi on the drill pipe, led the well site leaders and the rig crew to the incorrect view that the negative-pressure test was successful and that well integrity was established.”

The report also said this: “The investigation team has found no evidence that the rig crew or well site leaders consulted anyone outside their team about the pressure abnormality.” It did not mention that Don Vidrine had telephoned BP’s senior drilling engineer, Mark Hafle, at 8:52 that evening and told him about the pressure. BP’s investigators had interviewed Hafle on 8 July 2010, with his lawyers and BP’s counsel present, and had the notes.

Four years later Judge Carl Barbier found that sentence “patently false.” Bly testified that the call had been left out because it came “after the fact, after the test had been accepted”; a colleague on the team, Steve Robinson, said he “didn’t see it as being causal because the interpretation of the test wasn’t done in this call.” The judge called those explanations “untenable,” since thirty-six minutes had remained after the call in which the well could have been shut in, and wrote: “The Court infers that BP’s investigation team recognized the importance of the 8:52 p.m. phone call and chose to omit it from the BP Accident Investigation Report to avoid casting further blame on BP.”

The bladder effect after the blowout

Robert Kaluza, the day well site leader, went on defending the explanation. On 25 April 2010, five days after, he emailed BP management:

“Please consider this suggestion in the analysis about how this happened. I believe there is a bladder effect on the mud below an annular preventer as we discussed. As we know the pressure differential was approximately 1400 – 1500 psi across an 18 ¾[-inch] rubber annular preventer, 14.0 SOBM plus 16.0 ppg Spacer in the riser, seawater and SOBM below the annular bladder. Due to a bladder effect, pressure can and will build below the annular bladder due to the differential pressure but can not flow – the bladder prevents flow, but we see differential pressure on the other side of the bladder.”

On 27 April a BP vice-president, Mike Zanghi, forwarded it to Pat O’Bryan, the vice-president for drilling who had been on the rig that night. A week after the blowout Kaluza was still describing the test results as “rock solid.” He told BP’s investigators that if Jason Anderson had seen the phenomenon so many times before, it must be real; it was Anderson, the night toolpusher, who had named it, and Anderson had died on the drill floor.

Every investigation looked for the effect and none found it. The Chief Counsel’s team: “every industry expert that the Chief Counsel’s team spoke with agreed that no such phenomenon exists. Even if it did exist, any pressure caused by this ‘bladder effect’ would have disappeared after the rig crew bled off the drill pipe and kill line.” The court: the phenomenon “is not known to exist in the context of negative pressure tests, and no party has advanced the ‘bladder effect’ as a plausible explanation for the pressure anomaly during the negative pressure test.” Lee Lambert, the BP trainee who had been in the shack and had asked about the effect and accepted it, agreed on reflection that the explanation did not make sense.

The Commission and its Chief Counsel, 2011

The National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling, appointed by the President, reported on 11 January 2011. On the test it found that “the pressure data were not ambiguous. Rather, they showed repeatedly that formation fluids, in this case hydrocarbons, were flowing into the well,” and listed five things that may have contributed to the misreading: no standard procedure in the regulations or the industry; none in BP or Transocean, and no training; no specific procedure from BP’s Macondo team; no policy at BP requiring a call to shore about confusing data; and, through poor communication, no full appreciation by the men running the test of the context, a cement job with more against it than usual, in which they were running it. “It appears instead they started from the assumption that the well could not be flowing, and kept running tests and coming up with various explanations until they had convinced themselves their assumption was correct.”

The Commission’s Chief Counsel, Fred Bartlit, reported in February 2011 at much greater length. His team’s judgement was that the test “showed repeatedly over a three-hour period that the well lacked integrity,” that the men in the drill shack had “decided as a group that the test had succeeded,” and that the long time spent conducting and discussing it “shows a desire for consensus. It is possible, even likely, that this desire obscured the parties’ responsibilities.” Its management finding: “Given the risk factors attending the bottomhole cement, individuals on the rig should have been particularly attentive to anomalous pressure readings. Instead, it appears they began with the assumption that the cement job had been successful and kept running tests and proposing explanations until they convinced themselves that their assumption was correct.” It noted that BP had never told the rig that the test was carrying the whole weight of the cement, and that neither company had a rule requiring the result to be reported ashore, though both expected a call from anyone who was uncomfortable.

The joint investigation, 2011

The Coast Guard and the Minerals Management Service convened a joint investigation in April 2010, held seven sessions of public hearings and heard more than eighty witnesses; it was at those hearings, from May 2010, that Harrell, Ezell, Pleasant, Lindner, Lambert, Winslow and the others gave the evidence the reports quote. The Coast Guard’s volume, on the explosion, fire, evacuation and sinking, came out in April 2011. The BOEMRE panel’s volume, on the well, came out on 14 September 2011.

The panel calculated what the drill pipe should have read when the preventer closed, 1,610 pounds, against the 2,339 recorded, and read the data’s sequence slightly differently from the Chief Counsel. On the call to Houston it found that Hafle had logged into the live well data at 1:25 that afternoon, opened the Macondo cementing log at 4:13, and stayed logged in until 5:27; that when Vidrine rang at about 8:50 “Hafle questioned Vidrine about the results of the negative test, but he chose not to investigate further by accessing and reviewing the available real-time data. Instead, Hafle chose to rely upon Vidrine’s assurance that the rig crew had successfully performed a negative test”; and that Hafle had stayed in the office until about 10:00 that night, and afterwards emailed himself an account of his day. The panel also noted that none of those in the “long” discussion had consulted the visiting executives, who between them had more than fifty years of drilling.

By then the rules had moved. On 30 September 2010 the Interior Department had issued an interim final rule, the Drilling Safety Rule, with new standards for well design, casing and cementing, and well control, and a Workplace Safety Rule requiring operators to manage their risks systematically. The panel’s first recommendation was that negative pressure tests be required by regulation on every well whose bore would be left underbalanced when the preventer and riser came off, which is every subsea well at abandonment.

The pleas, 2012 and 2013

On 15 November 2012 BP Exploration and Production agreed to plead guilty to fourteen counts: eleven of seaman’s manslaughter, one for each of the dead; one of obstructing Congress, for what it had told a committee about the size of the spill; a misdemeanour under the Clean Water Act; and a violation of the Migratory Bird Treaty Act. It agreed to pay $4 billion, the largest criminal resolution in American history to that date: by the court’s later accounting, $1.15 billion for the Clean Water Act, $100 million for the birds, $5.5 million for the eleven counts of manslaughter and $500,000 for the obstruction, with $2.394 billion to the National Fish and Wildlife Foundation and $350 million to the National Academy of Sciences. The court accepted the plea on 29 January 2013 and put the company on probation for five years.

Exhibit A to the plea said, in part: “The [BP] Well Site Leaders were responsible for supervising the negative pressure test conducted by Transocean. . . . [T]he negative pressure test performed on the Macondo Well provided multiple indications that the wellbore was not secure. BP’s Well Site Leaders negligently supervised the negative pressure test during this time, failed to alert engineers on the shore of these indications, and along with others, ultimately deemed the negative pressure test a success, all in violation of the applicable duty of care. . . . BP’s negligent conduct, among others, was a proximate cause of the deaths of eleven men and pollution resulting from the Macondo Well blowout.”

The same day a grand jury in New Orleans indicted Kaluza and Vidrine, each on eleven counts of seaman’s manslaughter, eleven of involuntary manslaughter and one violation of the Clean Water Act. A BP vice-president, David Rainey, was charged with obstructing Congress and false statements about the flow rate, and an engineer, Kurt Mix, had already been charged with deleting text messages.

On 3 January 2013 Transocean Deepwater agreed to plead guilty to a misdemeanour under the Clean Water Act and to pay $1.4 billion: $400 million in criminal penalties and $1 billion in civil penalties, the latter under a consent decree the court entered on 19 February 2013. Its plea said: “TRANSOCEAN, together with BP, conducted negative testing on the Macondo well. . . . Both BP and defendant TRANSOCEAN continued to observe abnormal pressure on the drill pipe while monitoring the kill line for flow. . . . BP and defendant TRANSOCEAN did not take further steps to investigate the source of the abnormal drill pipe pressure, which was neither correctly explained nor remediated.” Its conduct “violated its duty to exercise well control in accordance with the standard of care applicable in the deepwater oil exploration industry,” and “together with the negligent conduct of others, was a proximate cause of the blowout.”

The trial, 2013 to 2016

The civil cases, several hundred of them, were gathered before Judge Barbier of the Eastern District of Louisiana as a multidistrict litigation and tried in phases. Phase One, on the causes of the blowout, ran from 25 February to 17 April 2013. The judge’s findings came on 4 September 2014, revised five days later, 153 pages.

On the test they were plain. “No party disputes that it is a safety-critical test,” and in the words of Halliburton’s expert, Dr Beck, “The negative pressure test is the most critical test that is run prior to removing the blowout preventer.” The criteria were “easily understood in the drilling industry”: once bled to zero, the pressure must stay at zero, or, if the test is a flow check, nothing must flow; “If there is either pressure or flow, then the test has failed.” The United States’ expert, Richard Heenan, called it a “pass-fail” test; Transocean’s, Calvin Barnhill: “This isn’t baseball, the tie doesn’t go to the runner, the tie goes to the failed test. So if it’s good, it’s good; if it’s inconclusive or if it’s bad, it’s not a good test.”

The court found that by about 5:30 “there were significant anomalies that should have indicated that the well potentially was in communication with the reservoir, or at least that the test had failed and needed to be restarted”; that the kill line’s zero “was obviously a false reading”; that “the one thing the 1,400 psi reading absolutely precluded was a determination that the negative pressure test was successful or that the well was secure”; and that “if the negative pressure test had been correctly interpreted, the blowout, explosion, fire, and oil spill would have been averted.” Both companies were responsible for the misreading, as both had admitted in their pleas; BP, which had the final say and the engineers ashore, was the more culpable. Of the 8:52 call the court found that Hafle “not only recognized that the test could not be considered a success, he was advising Vidrine how to troubleshoot the problem,” that thirty-six minutes had remained after it, and that Vidrine, who had told BP’s investigators the results looked “squirrely” to him, “did not order another negative pressure test after the phone call” but at 9:14 “affirmatively ordered that the pumps…be restarted and that displacement continue.” Of the drill crew: “they were attentive to the well during the negative pressure test and took the procedure seriously.” The court found BP’s conduct grossly negligent, and divided the fault: BP sixty-seven per cent, Transocean thirty, Halliburton three.

Phase Two, on the flow, was tried in the autumn of 2013; the findings of 15 January 2015 put the oil that left the reservoir at about 4.0 million barrels and the oil discharged into the Gulf, after what was collected at the wellhead, at 3.19 million. The penalty phase did not reach a judgement against BP. On 5 October 2015 the United States and the five Gulf states announced a settlement of $20.8 billion, the largest with a single entity in the Justice Department’s history: a Clean Water Act penalty of $5.5 billion, $8.1 billion in natural resource damages, $4.9 billion to the states and up to $1 billion to local governments. The consent decree was entered on 4 April 2016. The court’s penalty findings of 30 November 2015 assessed BP’s partner Anadarko $159.5 million.

The two well site leaders

Kaluza and Vidrine had declined to speak to the investigators after the first days, one citing his health and the other the Fifth Amendment, and neither testified at the trial. Their indictments of November 2012 for manslaughter were the only criminal charges that reached the men who had decided the test. The manslaughter counts were dropped in 2015. On 2 December 2015 Vidrine pleaded guilty to a misdemeanour under the Clean Water Act, negligent discharge. He testified for the government at Kaluza’s trial in February 2016; on 27 February the jury acquitted Kaluza of the same misdemeanour. On 6 April 2016 Vidrine was sentenced to ten months’ probation. The Justice Department’s bulletin recorded that Kaluza “is the final defendant to be prosecuted for the 2010 Deepwater Horizon oil spill disaster.” Rainey had been acquitted in June 2015; Mix’s conviction had been set aside and he had pleaded guilty to a lesser computer offence; Halliburton and one of its managers had pleaded guilty to destroying evidence. Of the four BP employees charged, none went to prison.

Sources

• BP, Deepwater Horizon Accident Investigation Report, 8 September 2010, key finding 3 and page 89. bp.com
• National Commission, Deep Water, chapter 4, and Chief Counsel’s Report, chapter 4.6. govinfo.gov, govinfo.gov
• BOEMRE, Report Regarding the Causes of the April 20, 2010 Macondo Well Blowout, sections VII and XIX, and the Coast Guard’s volume I. bsee.gov
• Findings of Fact and Conclusions of Law, Phase One, 4 September 2014 (revised 9 September), paragraphs 13, 236 to 282, and the allocation of fault; and Findings of Fact and Conclusions of Law, Penalty Phase, 30 November 2015, paragraphs 64 and 65 and the Anadarko penalty. uscourts.gov, laed.uscourts.gov
• Department of Justice, press releases of 15 November 2012, 3 January 2013 and 5 October 2015, and the Environmental Crimes Section’s bulletins of January, March and May 2016. justice.gov, 2012, justice.gov, 2013, justice.gov, 2015, bulletin, May 2016