Analysis of Soil Erosion Rates of Radionuclides Flowed in River and Estuary

Abstract

Suh, K-S.; Min, B.-I.; Yang, B.-M.; Kim, J.; Kim, S., and Park, K., 2019. Analysis for the soil erosion rates of radionuclide flowed in river and estuary. In: Lee, J.L.; Yoon, J.-S.; Cho, W.C.; Muin, M., and Lee, J. (eds.), The 3rd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 91, pp. 241-245. Coconut Creek (Florida), ISSN 0749-0208.A large amount of radioactive material was deposited in surface soil near the nuclear power plant after the Fukushima nuclear accident in 2011. Cesium radioisotope deposited on the land was adsorbed strongly in soil and it moved together in sorptive form with soil. Radioisotopes adsorbed in soil may transport by wind, rain, and other external forces and they reach rivers, lakes and estuaries near the contaminated area. In this study, the effects of soil erosion by precipitation are evaluated to analyze the long-term behavior of radionculides adsorbed in soil, and a numerical model was also established. A field experiment was carried out to measure the soil erosion rates by rainfall and the data observed from the experiment were used as input parameters in the numerical model. The numerical simulations have been improved by considering the initial moisture function in the model. Also, the accuracy of the numerical solution was increased by analyzing the correlation between rain intensity and soil erosion, and by application of the multi-layered scheme according to the depth in soil.