In a oil storage depot, at around 1:15 pm, a train consisting of 10 wagons with 90 tonnes of heating oil and 10 wagons with 90 tonnes of diesel derailed at a switch while positioning itself on to track no. 2 at low speed (approx. 6 km/hr): a section of the train was on track no. 2, the other on track no. 1. The train conductor pushing the tanks immediately stopped the convoy. The freight company activated the emergency plan, and depot staff activated the IOP and alerted the Classified Facilities Inspectorate, which visited the site. The two rail tracks were deformed and two wagons were slightly damaged (ladders, railings). External fire-fighters came to the site and observed the absence of any hydrocarbon leak. The rest of the train (16 wagons) was moved so as not to block the crossing and disrupt traffic. The lifting service of the railway company repositioned the wagon, which had derailed. The next morning, the remaining wagons were evacuated after reinforcing the section of damaged rails. Tracks were repaired and, following Inspectorate authorisation, the tank wagons were able to resume deliveries. During these operations, the depot surveillance agent increased its inspection patrols and the fire water cannon was connected to the foam system to protect the wagons remaining onsite.

The switch lever B of track no. 2 towards track no. 1 did not have a mechanical locking device and rolled back after the train and five wagons had passed. The movement of the switch between the passage of the first and second wagon was helped by the lack of lubrication on the switch, the reduced convoy speed and the high level of wagon loading. At first, the operator added a system to lock the switch control lever. It had to be selected with each reception and its position controlled: the instruction for receiving by rail was updated and the plant technicians were informed. Given that the switch controls could not be removed during the works, they were subsequently replaced by lockable equipment (type I levers or trailing points). The operator updated the prevention plan, the connection agreement, the service contract (flexible articulation between wagons), the lease contract for wagons over the section concerned with equipment maintenance (lubrication of the bumpers and trays) and added the scenario of rerouting a wagon without unloading to the IOP. The experience feedback of this accident was sent to the group’s other sites.