Consideration on roles and relationship between observations/measurements and model predictions for environmental consequence assessments for nuclear facilities

Togawa, Orihiko; Okura, Takehisa; Kimura, Masanori

JAEA-Review 2022-049, 76 Pages, 2023/01

JAEA-Review-2022-049.pdf:3.74MB

Before construction and after operation of nuclear facilities, environmental consequence assessments are conducted for normal operation and an emergency. These assessments mainly aim at confirming safety for the public around the facilities and producing relief for them. Environmental consequence assessments are carried out using observations/ measurements by environmental monitoring and/or model predictions by calculation models, sometimes using either of which and at other times using both them, according to the situations and necessities. First, this report investigates methods, roles, merits/demerits and relationship between observations/measurements and model predictions which are used for environmental consequence assessments of nuclear facilities, especially holding up a spent nuclear fuel reprocessing plant at Rokkasho, Aomori as an example. Next, it explains representative examples of utilization of data on observations/measurements and results on model predictions, and considers points of attention at using them. Finally, the report describes future direction, for example, improvements of observations/measurements and model predictions, and fusion of both them.

Model intercomparison of atmospheric Cs from the Fukushima Daiichi Nuclear Power Plant accident; Simulations based on identical input data

Sato, Yosuke*; Takigawa, Masayuki*; Sekiyama, Tsuyoshi*; Kajino, Mizuo*; Terada, Hiroaki; Nagai, Haruyasu; Kondo, Hiroaki*; Uchida, Junya*; Goto, Daisuke*; Qulo, D.*; et al.

Journal of Geophysical Research; Atmospheres, 123(20), p.11748 - 11765, 2018/10

https://doi.org/10.1029/2018JD029144

A model intercomparison of the atmospheric dispersion of Cs emitted following the Fukushima Daiichi Nuclear Power Plant accident was conducted by 12 models to understand the behavior of Cs in the atmosphere. The same meteorological data, horizontal grid resolution, and an emission inventory were applied to all the models to focus on the model variability originating from the processes included in each model. The multi-model ensemble captured 40% of the observed Cs events, and the figure-of-merit in space for the total deposition of Cs exceeded 80. Our analyses indicated that the meteorological data were most critical for reproducing the Cs events. The results also revealed that the differences among the models were originated from the deposition and diffusion processes when the meteorological field was simulated well. However, the models with strong diffusion tended to overestimate the Cs concentrations.

Applicability of a model predicting iodine-129 profile in a silver nitrate silica-gel column for dissolver off-gas treatment of fuel reprocessing

Mineo, Hideaki; Goto, Minoru; Iizuka, Masaru*; Fujisaki, Susumu; Hagiya, Hiromichi*; Uchiyama, Gunzo

Separation Science and Technology, 38(9), p.1981 - 2001, 2003/05

https://doi.org/10.1081/SS-120020130

no abstracts in English

Development of ocean pollution prediction system for Shimokita region; Model development and verification

Kobayashi, Takuya; Lee, S.; Chino, Masamichi

Journal of Nuclear Science and Technology, 39(2), p.171 - 179, 2002/02

https://doi.org/10.3327/jnst.39.171

A three-dimensional model system was developed to predict oceanic dispersions of radionuclides released into the eastern area of Shimokita Peninsula. This system is a combination of the Princeton Ocean Model (POM) for predicting ocean currents and a particle random walk model for oceanic dispersion of radionuclides. The model was verified by using measured currents, temperature and salinity at the coastal area of Shimokita, Aomori-ken, Japan, where a nuclear fuel reprocessing plant is under construction. The results obtained from simulations area as follows; (1) Wind and the Tsugaru Warm Current entering into the objective region through the Tsugaru Strait significantly affect the structure of current over the region. (2) POM can represent seasonal variations of the Tsugaru Warm Current well with hypothetical oceanographic data. The calculation succeeded to reproduce the coastal mode from winter to spring and the gyre mode from summer to autumn.

A Model on valence state evaluation of TRU nuclides in reprocessing solutions

Uchiyama, Gunzo; Fujine, Sachio; Yoshida, Zenko; Maeda, Mitsuru; *

JAERI-Research 98-005, 20 Pages, 1998/02

JAERI-Research-98-005.pdf:0.63MB

no abstracts in English

Development and manufacturing of bronze-processed Ta-Added NbSn wires for the ITER

*; *; *; *; *; Nishi, Masataka; Yoshida, Kiyoshi; Isono, Takaaki; Tsuji, Hiroshi

Teion Kogaku, 32(4), p.167 - 172, 1997/00

https://doi.org/10.2221/jcsj.32.167

no abstracts in English

Computer code system DSOCEAN for assessing the collective dose of Japanese due to radionuclides released to the ocean from a reprocessing plant

Togawa, Orihiko

Journal of Nuclear Science and Technology, 33(10), p.792 - 803, 1996/10

https://doi.org/10.3327/jnst.33.792

no abstracts in English

Application of neutron radiography to visualization and void fraction measurement of air-water two-phase flow in a small diameter tube

Hibiki, Takashi*; Mishima, Kaichiro*; Yoneda, Kenji*; Fujine, Shigenori*; Kanda, Keiji*; Nishihara, Hideaki*; Tsuruno, Akira; Matsubayashi, Masahito

Journal of Nuclear Science and Technology, 30(6), p.516 - 523, 1993/06

https://doi.org/10.1080/18811248.1993.9734513

no abstracts in English

Dynamic behaviors of fragments ejected from the surface of carbon materials by laser ablation

Yoda, Osamu; Miyashita, Atsumi; *; *

JAERI-M 92-173, 27 Pages, 1992/10

JAERI-M-92-173.pdf:1.22MB

no abstracts in English

Development of human-friendly and intelligent nulear reactor design support system; A Study of module integration methodology

Araya, Fumimasa; *; *;

Doryoku, Enerugi Gijutsu No Saizensen : Shimpojiumu Koen Rombunshu 1992, p.225 - 230, 1992/00

no abstracts in English