Radioactive Coolant Leak Reported at Finnish Nuclear Power Plant

The operator of the plant, TVO, stated that the recent incident posed no threat to personnel, the environment, or overall nuclear safety. The facility has been undergoing its scheduled annual maintenance shutdown since March 1, with work expected to continue until early May. While maintenance activities have remained on track, a significant operational event occurred on Friday, March 7, when radioactive coolant leaked into certain areas of the reactor containment.

The leak was attributed to human error, as a hatch on the reactor pool had not been securely closed. However, due to prompt safety measures, the radiation risk remained minimal.

TVO has launched an investigation into the event and will take the necessary steps to prevent similar occurrences in the future.

The spilled reactor coolant entered the containment area and was directed into the facility’s floor drain system, which is specifically designed to manage such leaks. This coolant, which circulates through the reactor pressure vessel, transfers heat to the secondary circuit via the steam generator before being recirculated.

Proper procedures will be followed for handling the radioactive wastewater using designated treatment systems. Cleanup efforts began promptly, and staff were informed of necessary changes regarding restricted access areas.

Currently, maintenance work at Olkiluoto 3 remains on schedule, and according to TVO, the incident has not impacted the planned timeline for the annual outage.

Photo credit: TVO. All rights reserved.