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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
Akitoshi Hotta, Hiroshi Shirai, Shinya Mizokami
Nuclear Science and Engineering | Volume 152 | Number 3 | March 2006 | Pages 292-305
Technical Paper | doi.org/10.13182/NSE06-A2583
Articles are hosted by Taylor and Francis Online.
A postulated single control rod drop transient was calculated for a typical boiling water reactor plant taking into account effects of detailed void distributions in those bundles neighboring the withdrawn control blade. Time-dependent pin power distributions were reconstructed by the plant simulator TRAC/BF1-ENTRÉE and were exported to the subchannel code NASCA.Macroscopic cross-section libraries based on flat and distorted void distributions were allocated in accordance with fuel location in a simplified two-way coupling method. Exposure trends of bundle neutronic properties were compared between two void distributions. Although the infinite multiplication factor was not influenced, the radial peaking factor increased significantly because of the void distortion caused by pin-by-pin exposure of fissile materials.The result with the combined cross sections was compared with those with the flat void cross sections. Application of the combined cross sections lowered the initial local peaking because of larger neutron leakage around the withdrawn control blade. The transient linear power density at the critical fuel rod increased more rapidly. A change in the fuel heat flux was attenuated because of the heat conduction delay. As a consequence of these effects, the peak cladding temperature became slightly lower than that of the flat void model.