Buncefield Report Faults PSM Failures, Complacency
Summarizing investigators' findings, the new report includes information that could not be disclosed while the companies involved were being prosecuted. The December 2005 incident is Britain's costliest industrial disaster at more than $1.6 billion.
The agencies that investigated the explosion and ensuing five-day fire that devastated the Buncefield Oil Storage Depot in December 2005 have issued a final report summarizing the causes. The report contains information that could not be disclosed while the companies involved were being prosecuted. The chairman of the COMAH Competent Authority Strategic Management Group, Gordon MacDonald, writes in the introduction that the report was produced "so that everyone in major hazard industries – not just those involved in fuel storage – can learn from this incident, understand what went wrong, and take away lessons that are relevant to them." He adds, "Although five years have passed since the incident, the information and advice in this report is still highly relevant today."
The incident is Britain's costliest industrial disaster at more than $1.6 billion in damage. Photos in the report show wrecked fuel storage tanks as they lay after the fires finally were extinguished. The group has worked since then with industry and trade unions to improve safety at all UK sites storing large volumes of gasoline.
The report says the incident began as Tank 912 was being filled the night of Dec. 10. A gauge allowed employees to monitor the filling operation, and an independent high-level switch should have shut down the operation automatically if the tank overfilled. But the first gauge was stuck, as had happened repeatedly since the tank had been serviced in August 2005, and the switch was inoperable. A large amount of gasoline overflowed, a vapor cloud formed, and this cloud ignited in a huge explosion.
The report says a padlock was needed for the switch to retain its check lever in a working position, but the switch supplier "did not communicate this critical point to the installer and maintenance contractor or the site operator. Because of this lack of understanding, the padlock was not fitted."
A dike around Tank 912 and a system of drains and catchments to catch spilled fuel both failed, and the report says those containment systems were inadequately designed and maintained. The report states:
- Management systems in place relating to tank filling were both deficient and not properly followed, despite the fact that the systems were independently audited.
- Pressures on staff had been increasing before the incident. The site was fed by three pipelines, two of which control room staff had little control over in terms of flow rates and timing of deliveries. This meant staff did not have sufficient information easily available to them to manage precisely the storage of incoming fuel.
- Throughput had increased at the site. This put more pressure on site management and staff and further degraded their ability to monitor the receipt and storage of fuel. The pressure on staff was made worse by a lack of engineering support from head office.
These pressures "created a culture where keeping the process operating was the primary focus and process safety did not get the attention, resources or priority that it required," it says.
Five companies were fined a total of $15.4 million in July 2010 for their roles in the disaster. "When passing sentence on the defendants at St Albans Crown Court on 16 July 2010, the Judge, the Hon Mr Justice Calvert-Smith, commented that cost cutting per se was not put forward as a major feature of the prosecution case, but the failings had more to do with slackness, inefficiency and a more-or-less complacent approach to matters of safety," MacDonald wrote. "I therefore ask all in the major hazard industries to look carefully at your own operations in the light of the management and technical failings that lay behind this incident, and the important developments in the meantime."