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Radioactivity Dynamics in River System

(2015)

How is the cesium concentration in river water changing over time? 【Southern Fukushima prefecture】

In all rivers in Fukushima Prefecture, the concentration of radioactive cesium in river water tends to decrease gradually over time.

This is because the concentration of radioactive cesium in sediment discharge from mountain areas is also tending to decrease over time. (see also : Q Is there a continuous input of cesium contamination to rivers from forests?)

Time-dependence of 137Cs concentration in river water in northern Fukushima Prefecture.

Fig.1 Time-dependence of 137Cs concentration in river water in northern Fukushima Prefecture

Reference: Report on the Project for the Nuclear Regulatory Agency, “Data Accumulation for Distribution of Radioactive Materials Released from Fukushima Daiichi Nuclear Power Station, TEPCO and Development of Migration Model” (FY 2014).