Preface to the special issue on the Fukushima Daiichi Nuclear Power Plant accident and geochemistry; 10 years after the Fukushima accident

Tanaka, Kazuya; Yamasaki, Shinya*

Chikyu Kagaku, 55(4), p.93 - 95, 2021/12

https://doi.org/10.14934/chikyukagaku.55.93

Ten years have passed since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. In this special issue, we compiled review papers on the environmental behavior of the FDNPP-derived radionuclides from various research fields. This special issue shows that various research fields contributed to better understandings on the environmental behavior of the FDNPP-derived radionuclides.

Measurement of air dose rates by walk survey using KURAMA-II within 80 km range from Fukushima Dai-ichi Nuclear Power Plant

Ando, Masaki

Hokeikyo Nyusu, (63), p.2 - 5, 2019/04

http://www.irm.or.jp/news63.pdf

This is a commentary on the measurement of air dose rates by walk survey using KURAMA-II within 80 km range from the Fukushima Dai-ichi Nuclear Power Plant, which has been conducted as a commissioned research from the Nuclear Regulation Authority. The outline of KURAMA-II, the distribution map of air dose rates obtained by walk surveys, and the result of analysis concerning the decreasing trend of air dose rates are introduced based on the previous reports and thesis.

Risk communication practice after the Fukushima Daiichi Nuclear Power Station Accident; Interactive explanatory meeting on radiation and its health effects in Ibaraki prefecture

Ayame, Junko; Sugiyama, Kenji; Takashita, Hirofumi; Yamamoto, Ryuichi

JAEA-Review 2015-016, 182 Pages, 2016/02

JAEA-Review-2015-016.pdf:19.2MB

Nuclear Fuel Cycle Engineering Laboratories (NCL) of JAEA has held the explanatory meetings in Ibaraki prefecture since May 2011 in order to transmit factual information and reduce the excessive anxiety about radiation risk. Applying to our past risk communication process to the explanatory meetings, we built a process of interactivity between participants and our staff for the meetings. We incorporated the participants' needs into the meetings, and, as far as possible, we had interactive two-way communication so that the meetings were not one-way and persuasive but promote mutual understanding. According to the opinions and the results of questionnaire survey that were received from the participants, it became evident that the interactive explanatory meetings were effective in reducing participants' anxiety. This report explains the risk communication process for carrying out the explanatory meeting, and shows the activities of the meetings, questions and opinions from the participants, and questionnaire results that NCL implemented.

Calamity at Chernobyl

Malinauskas, A. P.*; Buchanan, J. R.*; Lorenz, R. A.*;

Mech.Eng., 109(2), p.50 - 53, 1987/02

no abstracts in English

Long-term assessment of transport of radioactive contaminant in the environment of Fukushima (F-TRACE project), 18; Migration behavior of radioactive cesium in a river system in eastern Fukushima

Nakanishi, Takahiro; Hagiwara, Hiroki

no journal, , 

Radiocesium released during the Fukushima Daiichi Nuclear Power Plant accident was largely deposited in the terrestrial environment. We estimated the fluvial discharge rate of radiocesium from catchment and the deposition rate on floodplain, by the continuous monitoring systems and soil profiles on floodplain.

Development of -ray directional radiation dose detector with good efficiency for field survey

Yamamori, Ryo*; Kobayashi, Hikaru*; Honta, Shohei*; Yoshino, Hiroshi*; Nozaki, Atsuo*; Ichijo, Yusuke*; Hijikata, Yoshio*; Yoshida, Hiroko*; Furuta, Takuya

no journal, , 

Understanding radiation field is important to predict radiation dose rate in newly constructing buildings in an area widely contaminated by radioactive nuclei. Directional spectra of the radiations are important to consider the shielding effect of the building. We adopts a method to measure the directional spectra by adopting a plate of lead collimator in front of the scintillator and subtract the values from the spectra measured without lead collimator. We investigated a possible weight saving detection system having sufficient detection efficiency. The investigation was carried out for the condition of the collimator radius ( = 10, 15, 20 cm) and the distance between collimator and detector ( = 1, 3, 5 cm). We found that three combinations satisfied the 90 field view and the detection efficiency became better with larger collimator radius. On the other hand, larger collimator radius indicate heavier detection system. Therefore, we developed an optimum detection system for field survey with the 15 cm diameter plate (10kg), the scintillator (3.4kg), and the folder (1.0kg).

Similarity of composition between silicate glass of the Type A insoluble Cs particles and filters of stand-by gas treatment system line in Unit 3

Hagiwara, Hiroki; Imoto, Jumpei; Hidaka, Akihide

no journal, , 

no abstracts in English

Estimation of radiocesium uptake from forest floor in Japanese cedar and Japanese konara oak stands of the Abukuma Mountains, Fukushima

Niizato, Tadafumi; Sasaki, Yoshito; Ito, Satomi; Watanabe, Takayoshi; Amamiya, Hiroki*

no journal, , 

An understanding of long-term environmental dynamics of radiocesium in forested area, which is released by the TEPCO's Fukushima Dai-ichi Nuclear Power Plant accident, is a key issue for predicting the future forest products radioactivity. In this paper we present the radiocesium uptake from forest floor in an evergreen Japanese cedar and a deciduous Japanese konara oak forests of the Abukuma Mountains, Fukushima. An investigation was conducted from 2015 to 2019. According to the International Biological Programme, IBP, annual radiocesium uptake from forest floor to the stand is estimated as follows; annual radiocesium increment associated with tree growth plus annual loss through litterfall, stemflow, and throughfall. The rate of annual radiocesium uptake to the total inventory of the stands associated with tree growth were estimated to be 0.1 and 0.06% in Japanese konara oak and Japanese cedar stands, respectively. The sum of radiocesium uptake including the loss of radiocesium amount by litterfall, stemflow, and throughfall were 1.37 and 3.13% in the konara oak and the cedar stands, respectively. The rate of radiocesium uptake estimated are lower than the elemental uptake in deciduous tree stands near Kyoto by IBP. This indicate that the radiocesium uptake by the konara oak and the cedar stands is limited and no significant increase in radiocesium concentration of tree tissues is expected in the study stands.

Atmospheric dispersion simulation; WSPEEDI

Nagai, Haruyasu

no journal, , 

no abstracts in English