This report documents a heat transfer and shielding performance test conducted on a Ridihalgh. Eggers & Associates REA 2023 boiling water reactor (BWR} spent fuel storage cask. The experimental work was conducted for the U.S. Department of Energy's (DOE) Commercial Spent Fuel Management Program by the Pacific Northwest Laboratory (PNL} and General Electric at the latter's Morris Operation (GE-MO). The testing effort consisted of three parts: pretest preparations, performance testing. and post-test activities. Pretest preparations included conducting cask handling dry runs and characterizing BWR spent fuel assemblies from Nebraska Public Power District's Cooper Nuclear Station. The performance test matrix included 14 runs consisting of two loadings, two cask orientations, and three backfill environments. Post-test activities included calorimetry and axial radiation scans of selected fuel assemblies, in-basin sipping of each assembly, crud collection, video and photographic scans, and decontamination of the cask interior and exterior.The REA 2023 spent fuel storage cask consists of a double containment design with silicone rubber 0-rings for sealing the primary lid of the inner cavity and a welded final closure on the secondary cover. The cask has a smooth, painted, stainless steel outer skin; a lead/stainless steel gamma shield; and a water/glycol neutron shield. The fuel basket is constructed of stainless steel clad Boral for criticality control, copper plates to conduct heat to the cask wall, and stainless steel for structural strength. The loaded cask is approximately 5 m tall and 2.25 m in diameter. and weighs approximately 100 tons. The basket is configured to hold 52 BWR spent fuel assemblies. The test fuel assemblies were of the General Electric 7x7 rod design. The REA 2023 BWR spent fuel storage cask design and manufacturing rights have been acquired by Mitsubishi of Japan, and the cask model designation has been changed to MSF IV.Dry runs of cask handling were performed prior to fuel being loaded in the cask and concurrent with fuel calorimetry. The objectives of the dry runs were to gain cask handling and loading experience and to finalize procedures. Each dry run was conducted successfully without significant problems. During the dry v dry runs, minor modifications were required to make the lifting yoke, yoke alignment guide, impact limiter, primary head bolts, neutron shield rupturo-: disk, and the cask pressurizing device more functionai.The Cooper spent fuel assemblies were cnaracterized using in-basin si~p ing, calorimetry, axial radiation scans, video scans, and 35-mm photograph,!.The results of these methods revealed no indication of any failed fuel befcre or after the performance test. Gas sampling during testing did indicate a leak in a fuel rod after the cask was fully loaded. However, the leak was calctlated to be extremely small, so small that its source was not identifiable by post-test sipping activities, video scans, or photography.Based on pretest calorimetry, fuel assembly decay heat rat...
