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Radioactivity Dynamics in River System


Will the concentration of radioactive cesium in lake water remain high unless contaminated sediments are removed from reservoir beds?

Sediments in riverbeds and river bottoms of the Ukedo River in Fukushima Prefecture strongly adsorb radioactive cesium. Even when the sediments are immersed in salt water, more than 80% of the radioactive cesium remains adsorbed.

Fig.1 Amount of cesium absorbed on soil in laboratory (magnification of adsorbed cesium to originally contained cesium)

Degree of cesium-desorbing ability for various concentrations of cesium adsorbed on soil taken from riverbeds and river bottoms of the Ukedo River.