The Swedish Final Repository for Low and Intermediate reactor waste (SFR) is the first facility for final radioactive waste disposal in the world. The SFR is located under the sea. The site investigations, research and documentation programmes carried out parallel to excavation are summarized together with information on the geological and geohydrological conditions. Some practical applications of the in- vestigation programmes are given.
The first final repository in the world for reactor waste (the SFR) orginally built for the actual purpose is located adjacent to the Forsmark Nuclear Power Plant on the eastern Baltic Sea coast of Sweden, about 130 km north of Stockholm (Figure 1).
According to Swedish law, the reactor owners bear the primary responsibility for safe handling and disposal of radioactive waste from their nuclear Power production plants. The Swedish nuclear utilities have delegated to their jointly owned company, the Swedish nuclear Fuel and Waste Management Company (SKB), the responsibility for the required R&D work, and the design, Construction and operation of the waste facilities.
The planning of the SFR started during he late seventies. Forsmark was choosen as a Possible site in 1980. Site in- vestigations were carried out in two phases up to 1983. The tunnelling works for the SFR started in October 1983, and the excavation works were finished in April 1986. The design and tunnelling works were carried out by the Swedish State Power Board (SSPB). Installation and checking of operational systems were completed in the beginning of 1988, and in April 1988 the Swedish Goverment gave the SKB permission to take the SFR into Operation.
The SFR is located close to the Forsmark power plant on the coast of the Baltic Sea. The repository is sited at a depth of 65 m under the sea about 1000 m from Forsmark harbour. Two parallel access tunnels extending about 1000 m were excavated from the harbour to the repository area. The cross-sectiona1 areas of the tunnels are 64 and 49 m2 respectively.
Phase 1 of the SFR includes one silo, four rock caverns and rooms for operation, service and technical supply (Figure 2). The combined length of tunnels, rock caverns, shafts and silo is 4.5 km. The quantity of 3rock excavated amounts to 430 000 m • Figure 1. Location of the SFR. 561 Figure 2. Layout of the SFR.
The layout meets the requirements for final disposal of the different types of low and intermediate reactor wastes, as well as safe and rational operation.
Three of the rock caverns are designed for waste with a low activity content. 'The waste is stored mainly in concrete containers I i.e. man-made barrieres. In the fourth rock cavern a concrete basin has been built to store the concrete containers. After complete filling with waste the basin will be sealed with concrete.
Most of the waste, primarily solidified ion- exchange resins, will be stored in the silo repository. The cavern is 70 m high and 31 m in diameter, housing a 50 m high concrete silo.