Development of behavior model of the persistent chemicals in watershed

2014 Fiscal Year Final Research Report

• Project/Area Number: 24710032
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Environmental impact assessment/Environmental policy
• Research Institution: Ritsumeikan University
• Principal Investigator: SATO Keisuke 立命館大学, 理工学部, 准教授 (30456694)
• Research Collaborator: IKEGAMI Maiko 京都大学, 原子炉実験所, 助教 (10625528) ; SMITH J. T. University of Portsmouth, Faculty of Science, Professor
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 放射性セシウム / 流域調査 / 福島県 / 河川流出 / 流域土壌 / 底質 / ダム / モデリング

Outline of Final Research Achievements

In this study, we conducted a survey of radioactive Cs contained in soil, sediment, vegetation, and lakes and rivers water in Natsui river basin. This study forcus on the runoff behavior, pollution level/scale and accumulation in soils/sediments by radioactive Cs-134 and Cs-137. By using the ratio of half-life on Cs-134 and Cs-137, it was evaluated quantitatively the source impact of nuclear accident. In addition, efforts to modeling to reproduce and forecasting the concentration of Cs, and predicted long-term changes in water contamination levels in the Kodama-dam lake and its inflow river. Results of the study, a relatively high Cs concentration was detected in the lake and pond sediments, that more than 90% that is the Fukushima nuclear power plant origin. It was found that the Cs concentration was estimated to a few Bq/L to about initially in the Lake of Kodama dam, reduction of up to about 0.1 Bq/L is expected in 20 years.

Free Research Field

環境情報工学，流域動態科学，微量汚染制御工学，水文水資源工学