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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Hinkley Point C gets over $6 billion in financing from Apollo
U.S.-based private capital group Apollo Global has committed £4.5 billion ($6.13 billion) in financing to EDF Energy, primarily to support the U.K.’s Hinkley Point C station. The move addresses funding needs left unmet since China General Nuclear Power Corporation—which originally planned to pay for one-third of the project—exited in 2023 amid U.K. government efforts to reduce Chinese involvement.
Josep M. Soler, Pekka Kekäläinen, Veli-Matti Pulkkanen, Luis Moreno, Aitor Iraola, Paolo Trinchero, Milan Hokr, Jakub Říha, Václava Havlová, Dagmar Trpkošová, Aleš Vetešník, Dušan Vopálka, Libor Gvoždík, Martin Milický, Michal Polák, Yuta Fukatsu, Tsuyoshi Ito, Yukio Tachi, Urban Svensson, Dong Kyu Park, Sung-Hoon Ji, Björn Gylling, G. William Lanyon
Nuclear Technology | Volume 209 | Number 11 | November 2023 | Pages 1765-1784
Regular Research Article | doi.org/10.1080/00295450.2023.2209234
Articles are hosted by Taylor and Francis Online.
The REPRO-TDE test was performed at a depth of about 400 m in the ONKALO underground research facility in Finland. Synthetic groundwater containing radionuclide tracers [tritiated water tracer (HTO), 36Cl, 22Na, 133Ba, and 134Cs] was circulated for about 4 years in a packed-off interval of the injection borehole. Tracer activities were additionally monitored in two observation boreholes. The test was the subject of a modeling exercise by the SKB GroundWater Flow and Transport of Solutes Task Force. Eleven teams participated in the exercise, using different model concepts and approaches. Predictive model calculations were based on laboratory-based information concerning porosities, diffusion coefficients, and sorption partition coefficients. After the experimental results were made available, the teams were able to revise their models to reproduce the observations.
General conclusions from these back-analysis calculations include the need for reduced effective diffusion coefficients for 36Cl compared to those applicable to HTO (anion exclusion), the need to implement weaker sorption for 22Na compared to results from laboratory batch sorption experiments, and the observation of large differences between the theoretical initial concentrations for the strongly sorbing 133Ba and 134Cs, and the first measured values a few hours after tracer injection.
Different teams applied different concepts, concerning mainly the implementation of isotropic versus anisotropic diffusion, or the possible existence of borehole disturbed zones around the different boreholes. The role of microstructure was also addressed in two of the models.