Determination of ¹⁴C Concentrations in Vegetation Collected near a Nuclear Power Plant with Boiling Water Reactors and Estimation of an Amount of ¹⁴C Released from the Plant

Abstract

Concentrations of ¹⁴C in vegetation collected near a nuclear power plant with two boiling water reactors were measured by a liquid scintillation counting technique to estimate the effects of ¹⁴C released from the nuclear power plant on the environment. The average ¹⁴C concentration in the vegetation collected near the nuclear plant was about 20mBq/g carbon higher than that collected from the environment where there was no effect of nuclear power plants. The increase in the ¹⁴C concentration in the vegetation was attributed to photosynthetic uptake of ¹⁴CO₂ discharged from the nuclear power plant under normal operation. The elevated level of ¹⁴C content in the vegetation enables us to evaluate the discharged rate of ¹⁴C from the nuclear power plant and has led to an estimation of 0.36TBq/(GW·a) which is comparable to values reported on other BWRs.