Comments on safety of reprocessed waste returned from abroad

The present report gives some comments on the safety of storage of wastes returned from abroad after being reprocessed. The properties of wastes to be returned should be evaluated in relation to the performance of the storage facilities in which the wastes are to be stored. Evaluation of the wastes should cover those properties associated with storage (origin, form, processing process used, internal radioactivity, chemical composition, etc.), thermal nature (calorific value, heat conductivity, specific heat, etc.) and exposure risk (material, shape and size of container, etc.). Requirements for storage facilities are listed and comments are given. Such requirements are associated with basic location conditions of the facilities, normal-emergency conditions, containment, radiation shielding, exposure control, release of radioactive substances, radiation monitoring, installation of waste, cooling, earthquake, natural phenomena, fire, accidents, specifications-standards, and inspection-repair. For disposal, further studies are required to develop proper techniques. (Nogami, K.)