Developments in Spent Fuel Transport in Germany – Measures for Contamination Protection

Following the detection of contamination on the surfaces of transport flasks for spent fuel and on railcars in 1998, the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) established 10 criteria for the resumption of spent fuel transports to avoid contamination problems in future. To fulfil these criteria German NPPs and the reprocessing plants of COGEMA, France, and BNFL, UK, developed certain actions and measures and identified a number of key parameters which required formal agreement. On this basis transports were resumed in Germany in April 2001 encompassing • • • • additional protection measures for flask surfaces during loading and unloading under water, common measurement standards for contamination controls and enhanced number of such measurements during each transport cycle, improved documentation of contamination measurement results and of technical measures during flask handling and organisational measures to clearly define competencies and responsibilities within the NPPs and among the involved parties and to improve the associated communication. About three years after transports had been resumed, the additional measures are proving to be successful: No real contamination event occurred during this entire period. The reports on experiences issued by German NPPs and by the reprocessing plants in 2002/2003 mention no relevant difficulties arising from the additional measures. However, with regard to the number of contamination measurements, some modifications have been suggested and a reduced contamination control program for “routine transports” was developed in accordance with the BMU-criteria. According to German legal requirements spent fuel transports to reprocessing plants have to terminate by 30 June 2005. On these grounds and based on the positive experiences most German NPPs decided not to apply for any relevant modifications. Furthermore, experience shows that the additional collective doses to personnel were in fact not as high as anticipated, due to the enhanced measures and contamination controls, and did therefore not require substantial changes. It can be concluded that the introduced system of improvements was successful in avoiding the contamination problem.