Seismic Toppling Assessment of Cylindrical Nuclear Transport Flasks

A review of flask and spent fuel handling operations was carried out as part of a Site Safety staged improvement programme and one aspect of this review covered seismic capability. This review coincided with the introduction of a new spent fuel transport flask, known as the Used Fuel Flask (UFF). Prior to the introduction of the UFF, spent fuel was transported by the NTL3M flask. A new facility, under construction is designed to comply with modern standards with a full seismic capability to withstand a 1 in 10000 year plus 40% margins earthquake. At the existing facilities, which have a limited operational life until the new facility becomes operational, a 1 in 1000 year earthquake event was the agreed seismic withstand requirement.