Abstract
The Studsvik site was originally a research facility with many different activities going on. During the years some of the work was ended and the buildings and facilities were free released and some of them torn down.
Three research reactors, one in Stockholm and two in Studsvik, have been decommissioned and their sites have been released for unrestricted use. The waste produced was included in the Studsvik waste management system.
There are today ongoing decommissioning projects in Studsvik. One is the dismantling and free release of the old Active Central Laboratory, ACL, together with its ventilation building, ACF, another project is the decommissioning of the old evaporator facility.
A recently completed project is the decommissioning of the Van de Graaff accelerator building in Studsvik. The Van de Graaff accelerator was in use from 1962 to 1989. During 1990–1997 work was performed in the building with the aim to clean-up the building and to radiologically map the building including sampling and decontamination for free release. In 1998 a permit for decommissioning of the free released building was given from SSI and during 1999 the building itself was demolished.
Free release of metals have been carried out at Studsvik since 1987 and up to date 5700 tonnes have been melted of which 5000 tonnes have been free released. The aim of melting low-level scrap metals from the nuclear industry is to safely determine the radioactive content of the metals before the material is released for unrestricted reuse. Melting services are performed as a part of the decommissioning of the nuclear power plant Würgassen in Germany.
Decontamination for decommissioning, melting and free release of the material has been performed on two steam generators from the shutdown Ågesta PHWR. The project was performed in 1992–93 and has been reported earlier.
Studsvik has worked with decommissioning and free release since the 1980’ies. This paper gives some examples on different projects performed during these years. The paper also describes the procedures on how to release both buildings and material from regulatory control as well as pre-treatment method introduced in order to minimise the waste needed to be put into final storage.