Due to the number of incidents, the complexity of the investigation and the scale of the Complex it was necessary initially to sub-divide the overall investigation into the three incidents into a number of separate investigations each led by a separate Investigation Leader. Subsequently a number of common issues and themes from the initial investigations into the three incidents were identified and a series of additional investigations were also carried out.
HSE Specialist Inspectors in a range of disciplines (electrical, mechanical etc.) from a variety of different locations joined the investigation teams. Investigations carried out by SEPA concentrated on the emergency response and the environmental impact of the MP steam main rupture and the FCCU fire in particular.
Individual investigations were carried out covering the following areas shown below.
During the course of the investigations members of the investigation teams:
The Company, its employees and their Trade Union representatives provided full co-operation throughout the investigations and there was close liaison between the BP incident investigation teams and the Competent Authority incident investigation teams throughout the investigations.
Regulation 18 Duty
In the event of a Major Accident COMAH Regulation 18 requires the Competent Authority to prohibit continued operation or restart if there is evidence of a serious deficiency. In the case of the FCCU fire there was clear evidence to this effect. However a prohibition notice was not issued, as many of the plants were already not operating owing to the previous power loss and MP Steam incidents. In addition the response of BP was to instigate a Task Force to carry out a site wide review of all operations to ensure continued safe operation of plants that were currently operating and that plants that were currently shutdown were not restarted until they had undergone a full safety review.
BP immediately carried out an audit of each facility to identify concerns and tracked progress against the identified findings and recommendations. The Competent Authority received regular electronic updates of the current status of audits, actions and tracking of progress from BP and BP reported to the HSE daily for a 6 week period any issues that were identified. These actions on the part of BP addressed the concerns of the Competent Authority in relation to the restart and continued safe operation of plants under COMAH Regulation 18 and accordingly a formal prohibition notice was not considered necessary.
In the case of the FCCU the dangerous substance inventory had burned off or had been removed, the FCCU was badly damaged and could not be restarted, and BP had given a written undertaking that the FCCU would not be restarted until the Competent Authority had agreed BP proposals for increased safety measures. As a result the Competent Authority concluded that a COMAH prohibition notice under the regulation 18 duty was not required to ensure safety.
BP’s open and constructive dialogue with the Competent Authority was a welcome feature of the investigation and BP shared findings with the Competent Authority and sought Competent Authority views throughout the investigations.