After nearly 17 months of testimonies and inquiries, the Joint Investigative Team (JIT) of the Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE) and the US Coast Guard (USCG) issued its final report on the Macondo blowout and spill on 14 September.
Volume I of the report, released 22 April this year, covers five aspects of the investigation under the Coast Guard’s jurisdiction: the explosions of the Deepwater Horizon; the resulting fire; evacuations; the flooding and sinking of the Deepwater Horizon; and the safety systems of the rig and its owner.
Volume II covers areas of the investigation under BOEMRE’s jurisdiction and includes findings on the causes – direct and contributing – of the blowout and resulting explosion and fire.
The report finds that a central cause of the blowout was failure of a cement barrier in the production casing string and that BP, as the designated operator, was ultimately responsible for conducting operations at Macondo in a way that ensured safety and protection of personnel, equipment, natural resources and the environment.
The JIT also concludes that BP made a series of decisions in the days leading up to 20 April that complicated cementing operations, added incremental risk and may have contributed to the ultimate failure of the cement job. These decisions included:
• The use of only one cement barrier;
• The location of the production casing;
• The decision to install a lock-down sleeve; and
• The production casing cement job.
The panel further concludes that stronger and more comprehensive federal regulations might have reduced the likelihood of the Macondo blowout. In particular, regulations could be enhanced in the areas of cementing procedures and testing; BOP configuration and testing; well integrity testing; and other drilling operations. Drilling inspections also could be improved, such as in the way emergency disconnect systems and/or other BOP stack secondary system functions are evaluated.
This final report also presents findings in well design; cementing; possible flow paths; temporary abandonment of the Macondo well; kick detection and rig response; ignition source and explosion; the failure of the BOP on the Deepwater Horizon; regulatory findings and conclusions; and company practices.
It concludes with the panel’s recommendations on:
• Well design;
• Well integrity testing;
• Kick detection;
• Rig engine configuration;
• Blowout preventers; and
• Remote-operated vehicles.
The JIT was formed on 27 April 2010 by an order of the Departments of the Interior and the Homeland Security to investigate the causes of the Macondo blowout and to make recommendations for safe operations of future oil and gas activities on the US Outer Continental Shelf. The JIT held seven sessions of public hearings, received testimony from more than 80 witnesses and experts, and reviewed a large number of documents and exhibits pertaining to all aspects of the investigation.
Appendices to the report can be found here.