Control of Liquid Radioactive Wastes in JPDR

Abstract

The disposal of radioactive waste materials resulting from the operation of nuclear power reactor is a very important problem in the design and operation of nuclear power plant. This report reviews the control or regulation of liquid radioactive waste and the experimental results of the JPDR for the past three years.
Origin of the radioactive waste is mainly treated water in regeneration of radioactive resin and cooling water of incore monitor. Based on the experimental results of 1000hr continuous operation, the daily liquid waste discharged was about 26m³ in volume and 900μCi in activities.
These radioactive liquid wastes are treated by filteration and demineralized or storaged in the decay tank in some cases. Lastly it was measured by sampling methods. If liquid waste had less than 10^-4μCi/ml, it was discharged to the discharge canal which leads to ocean. This canal carries, at the same time, the cooling water of turbin condenser, about 6000m³/hr, which dilutes the concentration of liquid waste about 3000 in factor. Then, the concentration of radioactive isotopes in the liquid wastes leaving plant site was well below the MPC limits for unrestricted areas as established by the ICRP and Japanese Government authorities.