In May 2022, Teollisuuden Voima carried out measurements in the air of the Olkiluoto low and intermediate-level waste disposal facility and in the water of the collecting well, and detected a radioactive substance, tritium. Radiation safety significance of tritium is minor and local, and it does not cause any danger to the environment or people.
Teollisuuden Voima Oyj (TVO) disposes of low and intermediate-level waste generated at the Olkiluoto nuclear power plant in a final disposal facility excavated in the rock, which is located on the Olkiluoto island. There is also radioactive waste generated in state-run industry, medical care and research at the Olkiluoto final disposal facility.
The tritium measured in the air and in the collecting well water originates from the waste placed in the final disposal facility. In the waste cave, tritium is found, for example, in the filter rods and ion-exchange resins used in cleaning the process waters of nuclear power plants, in various sludges and in research samples. Tritium is also present in state-owned waste.
The measured tritium concentrations are very low and well below the discharge limits set for nuclear power plants. The observed concentrations have no impact on working in the waste management cave or on the radiation safety of the environment or residents.
In an inspection carried out in October 2022, the Radiation and Nuclear Safety Authority (STUK) required TVO to investigate the origin, leakage route and safety significance of tritium. TVO provided STUK with a clarification at the end of 2022. In its clarification, TVO considers the state's small quantities of radioactive waste as the probable origin of the tritium detected in the waste cave. TVO's clarification is under review by STUK. The purpose is to identify the causes of the event and any necessary corrective actions.
STUK reports on the observations of the October inspection in the triannual report on supervision published in January 2023. The report can be read here (in Finnish).
State-owned small quantities of radioactive waste are stored and disposed of in Olkiluoto
In Finland, the management of radioactive waste from outside the use of nuclear energy has been arranged so that the state receives the radioactive waste generated by the use of industry, health care and research facilities. The waste is stored in the intermediate storage in connection with the Olkiluoto final disposal facility and disposed of in the Olkiluoto waste cave.
The state is obligated to take care of radioactive waste if the owner of the radioactive waste is not known or is not able to take care of the safe disposal of the waste. This ensures that radioactive waste does not end up in conventional waste stations or in the environment.
Further information
STUK Media Services, tel. +358 10 850 4761
