Cask Loader program enables nuclear plants to standardize and streamline interim on-site storage of used fuel assemblies.

Entergy and other nuclear utilities are applying EPRI's Cask Loader software to plan and execute the loading of used fuel assemblies into dry cask storage. The software helps nuclear plants optimize cask loading cost and scheduling, ease crowding in spent fuel pools, analyze cask loading scenarios to plan future used fuel management strategies, and standardize dry cask storage procedures across multiple sites.

Dry cask storage presents data-management challenges. A given plant's spent fuel pools may contain several thousand fuel assemblies—each about 15 feet long and weighing approximately 700 pounds for a boiling water reactor assembly and about twice that for a pressurized water reactor assembly. Each assembly has different physical properties, such as fuel composition, radioactivity, decay heat and burnup. The various types of data associated with an individual fuel assembly and dry cask are often in different locations and some are not in electronic form. Manually sorting and prioritizing assemblies for loading into casks is time-consuming and costly.

Cask Loader helps users select the appropriate used-fuel assemblies for each cask and then prints utility move sheets and other required forms. This enables plant personnel to minimize fuel movement and significantly reduce documentation errors. Inputs to Cask Loader include fuel assembly as-built data, burnup, core location and failure status; core data, including cycle dates and exposures; and cask as-built data. Cask Loader populates the chosen casks based on each cask's technical specifications and the available fuel assemblies that are within these specifications.

"Using standardized loading procedures across multiple sites is much more cost effective than having each site use a different approach," said John Weiss, Senior Lead Engineer, Entergy. "Moreover, the software enables users to run many loading scenarios, making it a powerful tool for planning how to unload spent fuel pools over time in the most efficient and cost-effective manner. With Cask Loader, I know over time how I will be able to unload a pool so I don't run into problems in the future where I can't load a cask because there are no available fuel assemblies that meet the specific criteria of the cask manufacturer."

For more information, contact John Kessler at 704.595.2737 or kessler@epri.com.