A modeling approach to estimate 3H discharge from rivers: Comparison of discharge from the Fukushima Dai-ichi and inventory in seawater in the Fukushima coastal region

Estimation of H-3 discharge from river catchments is important to evaluate the effect of Fukushima Dai-ichi discharge and future planned H-3 release to the ocean on the coastal environment. Using a previously developed model based on the lank model and observed H-3 concentration in river water, the H-3 discharge from the Abukuma River and 13 other rivers in the Fukushima coastal region were estimated from June 2013 to March 2020. The H-3 discharge from catchments of the Abukuma River and 13 other rivers in the Fukushima coastal region during 2014-2019 were estimated to be 12-4.0113q/y. These values were approximately 2-22 times larger than the annual H-3 discharge from the Fukushima Dai-ichi after 2016, indicating the significance of H-3 discharge from the catchments through the rivers. This estimation is expected to be useful to evaluate and predict H-3 concentrations and inventories in the Fukushima coastal region for consideration of planned H-3 release to the ocean. (C) 2021 The Authors. Published by Elsevier B.V.

Automated summary

Estimation of H-3 discharge from river catchments in Fukushima coastal region shows significantly higher values than the discharge from Fukushima Dai-ichi nuclear power plant, indicating the importance of H-3 discharge through rivers. This estimation is useful for evaluating and predicting H-3 concentrations and inventories in the coastal region.