Using a Risk-Based Methodology for the Transfer of Radioactive Material within the Savannah River Site Boundary (Onsite Transfers)

摘要

Shipment of radioactive materials (RAM) is discussed in the Code of Federal Regulationsin parts of both 49 CFR and 10 CFR. The regulations provide the requirements and rulesnecessary for the safe shipment of RAM across public highways, railways, waterways,and through the air. These shipments are sometimes referred to as in-commerceshipments. Shipments of RAM entirely within the boundaries of Department of Energysites, such as the Savannah River Site (SRS), can be made using methodology allowingprovisions to maintain equivalent safety while deviating from the regulations forin-commerce shipments. These onsite shipments are known as transfers at the SRS.These transfers must follow the requirements approved in a site-specific TransportationSafety Document (TSD) [1]. The TSD defines how the site will transfer materials so thatthey have equivalence to the regulations. These equivalences are documented in anOnsite Safety Assessment (OSA). The OSA can show how a particular packaging usedonsite is equivalent to that which would be used for an in-commerce shipment. This isknown as a deterministic approach. However, when a deterministic approach is notviable, the TSD allows for a risk-based OSA to be written. These risk-based assessmentsshow that if a packaging does not provide the necessary safety to ensure that materials arenot released (during normal or accident conditions) then the worst-case release ofmaterials does not result in a dose consequence worse than that defined for the SRS. Thispaper will discuss recent challenges and successes using this methodology at the SRS.