Application of a New Japanese Chemical Decontamination Method to System Decontamination of Reactor Cooling System in the FUGEN Nuclear Power Station

摘要

A system chemical decontamination of the B-loop of the reactor cooling system of FUGEN was carried out by the newly developed oxidation-reduction decontamination method (HOP method) in February 1999. As a result of the decontamination, the dose rate of the piping surface in the overhaul work area decreased significantly, and a high average decontamination factor (DF) of up to 20 was obtained. The dose equivalent during the overhaul work was reduced to 0.8 man□Sv which was about 1/6 of the 4.5 mam□Sv estimated in the case of no decontamination.