16 February 2002 a radioactive leak from a pipeline, connecting Unit 1 reactor department and auxiliary building, was revealed. The leak came from a weld of a plug on the dead end of the pipeline supplying a boric acid solution from the spent fuel pools to a special water purification system, located in the auxiliary building. In the future the temporary plug shall be removed and the pipeline shall be extended to connect with future NPP units. As a result of the leak, 3 m3 of liquid of 2.84 x 10-6 Ci/l (0.105 GBq/m3) specific activity was released to the soil. A maximal dose rate at 1-meter distance from the soil was 7 mR/hour (≈ 0.5 nC/(kg.second.
30 m2 of the NPP territory was fenced off and decontaminated. Investigation of the case revealed procedure inadequacies in surveillance programs, what was the root cause of the event.
No personnel overexposure or off-site release has been occurred.
Event date: Sat, 16-02-2002