Design Approaches for Transportation of High Burnup Used Fuel

The approaches for handling high burnup used (HBU) fuels in the USA are, for the most part; at the reactor site (wet storage) and/or dry storage at ISFSI. Both of these storage options are considered as “interim” awaiting eventual recycling or disposal. These HBU fuels eventually need to be “transported” from the reactor site. The HBU fuels stored at reactor site (wet storage) and/or dry storage at ISFSI is licensed to meet the 10CFR Part 50 [1] and 10CFR Part 72 [2], respectively. Transportation regulations (10CFR Part 71) [3] have several requirements that are different than those for storage. Additionally, compliance requirements to transportation regulations have evolved over the time period that the used fuels have been in storage. Design analysis methods and computer codes have undergone significant changes over time. The current accepted practices and regulatory expectations have also evolved and are different than they were when these systems were designed and licensed for storage. This paper first will discuss the issues associated with HBU fuel including: 1. Potential for degradation of fuel cladding 2. Uncertainty associated with HBU fuel properties 3. Large radiation source terms Then this paper will examines some of the challenges and the regulatory compliance requirements for 10CFR Part 71 and how they affect the transportation licensing of HBU fuels: 1. Review the current regulatory requirements, guidance and issues related to transportation of HBU fuels 2. Develop an understanding on some important issues associated with licensing the transportation package with high burnup contents 3. Present perspective on the need for regulatory guidance to resolve emerging issues 4. Present some design approaches for transport licensing of HBU fuels