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Nuclear Energy Conference & Expo (NECX)
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.
Masato Takahashi
Nuclear Technology | Volume 135 | Number 3 | September 2001 | Pages 230-240
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT01-A3218
Articles are hosted by Taylor and Francis Online.
A new method for off-gas source estimation in plants with nondefective fuel is proposed. This method based on the activity ratio between 138Xe and 88Kr is able to directly estimate the off-gas source using only measurement data. The 138Xe to 88Kr activity ratio is decided on the basis of the fissile irradiation with the different neutron spectrum in the core region and the fission fragment emission rate into coolant. This method was applied to actual plant data, and it was demonstrated that the dominant source of off-gas in a plant with nondefective fuel is Pu produced by the burnup of uranium impurities in the core structure. The concentration of uranium impurities in cladding estimated by this method is consistent with the result of neutron activation analysis.
