The background to the incident was at 6:46 p.m. on Tuesday, September 20, an accidental release of flammable chemicals ignited, creating a fire that left two workers dead and resulted in significant property damage at the refinery, according to an update to the investigation by the Chemical Safety and Hazard Investigation Board (CSB).
In the investigation, the CSB is examining the valves and interconnected piping associated with the refinery’s fuel gas mix drum located in the crude 1 unit.
The fuel gas mix drum is primarily a vapor-filled vessel and is equipped with features to remove liquids that could be entrained with vapor or that otherwise enter the refinery’s fuel gas system.
CSB investigators are focusing on a release of flammable naphtha from the fuel gas mix drum, based on information from various sources at the refinery.
However, one thing that is hampering the investigation is access to the area surrounding the fuel gas mix drum is currently restricted due to the presence of asbestos fibers.
The CSB investigation team is conducting witness and employee interviews, documenting the incident scene, collecting equipment and equipment components, obtaining documents, and evaluating recorded process data.
Investigators are zeroing in on the fuel gas mix drum at the BP-Husky refinery after the fatal incident this past September.
Credit: CSB
To that end, the CSB team has already interviewed more than 80 people and anticipates interviewing 20-30 more.
Some other issues with the investigation include:
- BP, the Occupational Safety and Health Administration (OSHA), the United Steelworkers International and Local 1-346 are conducting parallel investigations of the incident.
- The CSB, OSHA, and BP-Husky Refining LLC signed an evidence and site control agreement to preserve evidence.
- BP, OSHA, and the United Steelworkers, which represents hourly workers at the refinery, have been cooperating with the CSB team.