Transportation Cask for Bare High Burnup Spent Nuclear Fuel

In support of the U.S. Department of Energy’s (DOE) “Spent Nuclear Fuel Transportation Cask Design Study,” AREVA Federal Services LLC has developed a conceptual design of a reusable rail transportation cask (the 6625B-HB) capable of shipping high burnup pressurized water reactor (PWR) and boiling water reactor (BWR) spent nuclear fuel (SNF) that can be placed either bare into a basket or packaged in a damaged fuel can (DFC), which is then placed in a basket1. The purpose of the DOE study was to develop information and data on transportation cask options that could be used for shipment of SNF from commercial reactor sites to an Interim Storage Facility (ISF). The DOE study will be used to support the development of options for decision-makers on the design of an integrated waste management system.The 6625B-HB would be capable of accommodating essentially the entire existing and future inventory of commercial light-water reactor SNF assemblies, including restrictive short-cooled, high-burnup SNF assemblies with a maximum burnup of 62.5 GWd/MTU and a minimum cooling time of 5 years. The 6625B-HB contains up to 24 PWR or 61 BWR SNF assemblies placed into baskets designed for holding either bare fuel or fuel packaged into DFCs.The 6625B-HB cask has been designed such that there is reasonable assurance that it could be certified by the Nuclear Regulatory Commission (NRC) under 10 CFR Part 71, fabricated within existing facilities, used by most utilities, and transported by rail. The level of detail developed for the 6625B-HB is intended to support the analyses and planning activities that DOE is performing in laying the groundwork for an integrated waste management system, which includes preparing for future large-scale transport of SNF. The development of the cask design was based on lessons learned and past AREVA experience with design, testing and acquiring certification of transportation packages. This paper describes the 6625B-HB package features, certification approach, and design challenges including: transporting bare fuel packaged in DFCs, package weight restrictions, and accommodation of high burnup fuel, which introduces challenges related to shielding and decay heat.