Certification of the NAC-LWT Cask for Shipment of Sodium Debris Bed Experiments

The Department of Energy Headquarters Certifying Official has issued a Certificate of Compliance for the shipment of sodium debris bed experiments (DBE) in the NAC International’s Legal Weight Truck (NAC-LWT) casks. The shipment is part of a major de-inventory project at Sandia National Laboratories. The sodium debris bed experiments consist of crucibles containing UO₂ immersed in sodium. The uranium is 93% enriched U²³⁵. Potential sodium-water reaction and criticality safety under hypothetical accident conditions of transport are the two major technical issues for the design and certification of the NAC-LWT casks for the DBE shipment. The certification review took ≈ 13 months, including one round of questions and responses and source-verification QA audits of the fabrication and welding of the DBE transport canisters at two locations.