Decommissioning of Creys-Malville nuclear power plant: radiological characterization

Creys-Malville French fast reactor was shut down a few years ago and it has now to be dismantled with the first EDF NPP. An essential stage in the decommissioning of the Creys-Malville NPP, and of any other nuclear decommissioning project, is the radiological characterization of the installation. Good knowledge of the initial radiological state of the reactor block is essential in order to ensure that the radiological risk is managed during the dismantling operations, and to provide the data necessary for subsequent waste management. Therefore, radiological characterization has to provide the best possible information on: - the total and the specific activity of the radio-elements present in the installation and the evolution of this activity in relation to the decay time; - distribution of the part due to activation and the part due to the contamination of the structures and components; - mapping of the dose equivalent rates in the reactor block and their evolution in time, under the specific influence of the different sources. To meet these objectives, the radiological inventory of the installation applies various methods, especially theoretical ones, using radiation protection calculation codes. The purpose of this paper is to describe the methods of radiological characterization in readiness for dismantling work and to organize the management of the waste produced by Creys-Malville reactor block dismantling operations. (author)