Activity level exceeds authorized limit in Pool C

Incident report

June 25, 1999

On June 25, 1999, a sample of water taken from Pool C at the UP2-800 plant registered an activity level that was slightly higher than the authorized limit (4 x 104 Bq/l versus 3.7 x 104 Bq/l). The water treatment system lowered pool water activity to below the authorized limits within the day.

The activity spike followed the transfer of a basket of fuel in semi-sealed containers from the NPH unloading pool to Pool C via the fuel canal. A recommendation was made to the nuclear safety authority to classify the deviation from operating parameters, which had no impact on operating personnel or the environment, as a level 1 event on the International Nuclear Event Scale.