Reactor Waste
Low-level and intermediate-level waste, also known as reactor waste, is generated during the operation and maintenance of a nuclear power plant. The nuclear power companies Teollisuuden Voima Oyj and Fortum Power and Heat Oy take care of their reactor waste themselves.
How Reactor Waste is Generated
Low-level waste is maintenance waste that has been contaminated with radioactive substances. Low-level waste includes, among other objects, protective plastic sheets, tools, protective clothing and towels used during maintenance work, as well as engine parts and piping removed from the plant. The compound used in cleaning the circulating water is intermediate-level waste. The annual amount of reactor waste generated in Olkiluoto is from 150 to 200 m³ and in Loviisa from 100 to 150 m³.
Treatment of Reactor Waste
Low-level waste is compressed and packed into 200-litre barrels. Non-compressible waste is packed into steel or concrete boxes. In Olkiluoto, the intermediate level ion-exchange resins is solidified into bitumen, packed into steel barrels and placed in the waste repository. In Loviisa, the waste is solidified into cement and packed into concrete barrels.
Final Disposal of Reactor Waste
Reactor waste is first stored inside the power plant and then in separate interim storage facilities for low and intermediate waste. From there, the waste is transferred to a repository facility (RW repository) excavated at the plant site.
The reactor waste repository at Olkiluoto was commissioned in 1992 and the one in Loviisa in 1997. The RW repositories have been excavated to a depth of 60 to 100 meters inside the bedrock. The waste is transferred to the repository through a tunnel with a special-purpose car. When the repository is no longer being used, all connections to the repository are sealed off. After that, the repository does not need any monitoring. Over time, the radioactive substances contained in the waste lose their harmful effects on the environment. The waste poses no threat to the biosphere.
