Finland’s Teollisuuden Voima Oyj (TVO), which is planning to build a very-low-level waste disposal facility in Olkiluoto, on 14 August submitted an environmental impact assessment (EIA) programme to the Ministry of Employment and the Economy. This would be the first such disposal facilities in Finland.
In Sweden, a similar disposal facility has been in operation since 1993. The EIA programme is the first step in the environmental impact assessment procedure and comprises the investigations and arrangements required to assess the environmental impact of the project. It is prepared by the responsible party and the Ministry of Economic Affairs and Employment acts as the coordinating authority.
A soil disposal facility is a structure built close to the ground, usually on the ground. The space consists of a waste backfill and various structural layers above and below it. Drainage and a water collection system will also be built in connection with the bottom, with which the quality of the water seeping through the space can be monitored. Waste placed on top of the substructure is enclosed in waste packages.
Very-low-level waste includes, for example, protective plastics and protective clothing that have been used during maintenance outages at a nuclear power plant. The size of the soil disposal facility is planned to be 90 x 115 metres. Waste packaging is disposed of in the facility every five years, and the part of the space filled with waste is temporarily sealed.Low- and intermediate-level operating waste generated at the Olkiluoto nuclear plant is currently disposed of in the VLJ repository commissioned in 1992. It comprises two rock silos, a connecting hall and auxiliary facilities constructed at a depth of 60-100 metres inside the bedrock. Low-level waste is deposited in the rock silo inside a concrete box, while a silo of steel-reinforced concrete has been constructed for intermediate-level waste in the other rock silo. The low-level waste is packed into 200-litre drums and compressed to half of its volume using a hydraulic press. The radioactivity of the containers is measured before storage. The low-level waste silo has a capacity of about 5000 cubic metres and the intermediate-level waste silo about 3500 cubic metres.