Impact of the Alternative Fuel Cycles on the Long Term Safety of Deep Geological Repository
16th Symposium of AER on VVER Reactor Physics and Reactor Safety (2006, Bratislava, Slovakia)
Actinide Transmutation and Spent Fuel Disposal
Abstract
Methodology for comparison of the long term safety of nuclear fuel cycles is discussed in this paper. The first step in this process is the collection of indicators which can be used to quantify the impact of each fuel cycle. Indicators such as activity fluxes to the biosphere, annual dose for a member of critical group of people and others were calculated to show how different fuel cycles modify the performace of the disposal system. We present here safety assessment results of evolution and human intrusion scenarios. Results for evolution scenarion were calculated by software AMBER, which is able to build dynamic compartmental models to represent the migration and fate of contaminants in the environment. Second part of this paper deals with the intruder scenario, particularly radiation load of workers who analyze borehole core excavated from the deep geological repository. Radiation load was calculated by VISIPLAN 3D ALARA planning tool software. A number of calculating models was defined for each of the fuel cycles. Calculating model estimates radiation load as external irradiation of people working near active borehole core. The results of these models are presented by dosimetric maps in the neighbourhood of borehole core and tables containing dose rate during working activities. The methodology presented in the paper can be finally used for the sustainability assessment of the advanced nuclear fuel cycles based on the Multi-Criteria Analysis approach.