Above the track, there are so-called snow galleries that are supposed to protect the track from snow, but at the site of the derailment, there was a hole in the snow gallery that facilitated the snow drifting onto the track and under the carriages, notes the Accident Investigation Commission.
During previous inspections and examinations, the hole in the wall of the snow gallery had not been noted or addressed.
The weather is pointed out as a contributing cause of the accident – it was blowing fresh to hard wind and the wind brought with it wet snow that packed and froze into hard drifts on the ground.
Due to ongoing work at the site, the train had to make a longer stop. The train had empty carriages with low axle load and when the train started rolling, some wheels and carriages were lifted by the packed snow and the train derailed.
The derailment that is now being investigated occurred only a few days after the track was reopened after a previous derailment.
