Root cause analysis was applied to a refinery naphtha tank overflow incident, which resulted in a toxic tort claim from workers at a nearby facility. Baker & O'Brien investigated the timeline that led to the incident, actions taken during and after, review of procedures, training, incident reporting, and spill response actions vis-vis the Mutual Aid System. After submitting our expert report, the matter was settled.

Refinery operators must adhere to strict regulations and have detailed practices and procedures in place to avoid and respond to hydrocarbon spills or vapor releases. Such incidents, when they occur, can be not only extremely costly in terms of clean-up and potential unit downtime, but can also lead to protracted litigation over environmental damage and/or injury to personnel. Although unexpected events can and do arise, detailed post-event analysis can often identify root causes, whether proper actions were taken, and if safety procedures require modification.

A large petroleum refinery suffered an unexpected power outage which caused a shutdown in a process unit. Following restoration of power, operators began implementation of their standard start-up procedures for the unit. However, during start-up, hydrocarbon vapor flowed through the piping leading to a naphtha tank, unintentionally entering the tank. Because it was an external "floating roof" design-to minimize vapor emissions-the vapor ingress forced some liquid naphtha to overflow onto the roof and enter the containment dike around the unit, simultaneously causing a vapor release. Following the incident, a nearby facility reported that several workers had complained of an unusual odor and had become ill. The affected workers filed a claim for damages against the offending refiner.

Baker & O'Brien was engaged to investigate the events leading up to the incident, as well as the actions taken by refinery operators before, during, and after. Our consultants identified the likely root cause of the incident, reviewed the start-up procedures for the unit after a power loss, the training and safety procedures in place, and the spill response actions taken. We also reviewed the reporting and incident classification actions following the release to assess whether they were in accordance with the Industrial Mutual Aid System in place for industries in the area. Our expert report was instrumental in avoiding trial and facilitating a settlement between the parties.