This second version of the Olkiluoto Site Report, produced by the OMTF (Olkiluoto Modelling Task Force), updates the Olkiluoto Site Report 2004 (Posiva 2005) with the data and knowledge obtained up to December 2005.<br/>The main product of the modelling has been to develop a descriptive model of the site (the Site Descriptive Model), i.e. a model describing the geometry, properties of the bedrock and the water and the associated interacting processes and mechanisms.

Finland signed the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management on 2 October 1997 and deposited the tools of acceptance on 10 February 2000. The Convention entered into force on 18 June 2001. The major generators of radioactive waste in Finland are the two nuclear power plants, the Loviisa and Olkiluoto plants. The Loviisa plant has two PWR units, operated by Fortum Power and Heat Oy, and the Olkiluoto plant two BWR units, operated by Teollisuuden Voima Oy.

Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Hastholmen in Loviisa, Kivetty in Aanekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Olkiluoto.

Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Hastholmen in Loviisa, Kivetty in Aanekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Romuvaara.

Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Hastholmen in Loviisa, Kivetty in Aanekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Kivetty.

Posiva Oy is studying the Finnish bedrock for the geological disposal of spent nuclear fuel. The study is based on the site selection research programme started originally in 1983. The programme is in accordance with the decision in principle by the Council of State in 1983 and aims at the selection of one site in 2000. Four sites, Hastholmen in Loviisa, Kivetty in Aanekoski, Olkiluoto in Eurajoki and Romuvaara in Kuhmo, have been studied in detail. This report summarises the results of the site investigations carried out at Hastholment.

Thorough long-term studies have shown that the Finnish bedrock is suitable for the permanent isolation of spent nuclear fuel from organic nature. Legislation requires that besides safety, an assessment be made of any other environmental impacts of the final disposal facility. Environmental impact assessment (EIA) in respect of the final disposal facility for spent nuclear fuel got under way in 1997 when Posiva Oy, which is responsible for the project, began work on an EIA programme.