A New Generation of Dry Transportable Storage for Spent Nuclear Fuel: NAC International’s Technology for Modular, Advanced Generation, Nuclear All-purpose Storage – The MAGNASTORTM System

U.S. nuclear utilities have been using dry storage of spent nuclear fuel for more than 20 years, and over the last decade or so, most nuclear plants that use dry spent fuel storage have shifted to transportable dry storage technologies, or multipurpose systems. Today, almost 470 canister-based concrete multipurpose canister systems (MCS) are loaded and stored at U. S. reactor sites. NAC has supplied more than 190 (>40%) of these loaded, first-generation concrete MCS, and a number of lessons have been learned about the design, licensing, and operations of dry storage technologies. NAC has taken a leading role in the development of a new generation of multipurpose technology that applies those lessons learned and improves the capabilities and economics of dry storage. The MAGNASTOR System was developed during 2003 and 2004 with extensive design review by NAC’s customer base, and, over the last three years, substantial progress has been achieved. This paper presents the characteristics and developments embodied within the MAGNASTOR design and provides a current update on the storage certification of the system. NAC has also pursued an ambitious and aggressive demonstration program that has included three phases of prototype fabrication using three separate manufacturers. These efforts definitively demonstrate the ease and simplicity of system fabrication and give us great confidence that the MAGNASTOR System can become a global technology. A key purpose of the MAGNASTOR System has been to improve the economics of dry MCS storage for the U. S. dry storage market. This paper will provide a summary of the economic impact that the MAGNASTOR System can have on dry storage costs for utility users, and similar impacts can be achieved globally. Finally, this paper will review the unique transport cask approach for MAGNASTOR, which represents an evolution in cask technology while retaining a number of successful and proven elements of earlier NAC rail/marine transport cask designs.