Noble gas leak detected in Olkiluoto 1 reactor since October – no impact on power production

A leak of noble gases has been detected in the Olkiluoto 1 nuclear reactor in western Finland since October, but it has not affected electricity generation or posed any safety risks, reports Finnish public broadcaster Yle.

The leak involves noble gases only, with no uranium escaping from the fuel rods, according to Teollisuuden Voima (TVO), the plant operator. A damaged fuel assembly in the reactor is no longer participating in the chain reaction that produces heat energy.

“The situation is very moderate and has had no impact on power production,” said TVO communications director Johanna Aho. She stressed that even minor deviations from normal operations in nuclear plants are treated with the utmost seriousness, though in this case no environmental risks have been identified.

A suspected leak in the Olkiluoto 2 unit remains unconfirmed. Authorities have not ruled out a possible leak based on a single indicator but have not verified it either.

Tomi Koskiniemi, the Radiation and Nuclear Safety Authority’s (STUK) inspection chief for Olkiluoto 1 and 2, confirmed that the safety significance of the leak is “extremely small.” The issue was first reported by regional newspaper Satakunnan Kansa.

TVO has implemented necessary measures in response to the situation.