German experiences on decommissioning illustrated by the activities at KRB A nuclear power plant

The German electricity supply companies have had an investigation carried out to find the most expedient way of decommissioning nuclear power plants at the end of the period of use. Two alternative scemes were proposed for this, safe enclosure of the plant and immediate total removal without safe enclosure. The study confirmed that both alternatives are technically feasible at present, but the latter case is impractical on account of the absence. Decommissioning work is at present going on for 5 German nuclear power stations. For KRB A decommissioning planning was initiated in 1980 and the plan was issued in 1982. Actual decommissioning work began in 1982 and has continued to the present time. Throught 1985, approx. 1500 tons of contaminated materials have been removed from the turbine building. About two thirds of this mass consists of steel and other metals, and one third of concrete and other non-reusable materials. The steel has been decontaminated to release levels and sold on the scrap market. About 400 tons of concrete turbine shielding were removed, decontaminated and released for unrestricted normal disposal. The amount of radioactive waste produced by decommissioning activities in the turbine house remains below 5% of dismantled material