Decommissioning waste conditioning. The point of view of the disposal facility operator

Centre de l'Aube disposal facility that is dedicated to short lived low and intermediate level waste was mainly designed for operational wastes. Waste packages were standardised in order to meet operating facilities needs, even if some types of packages could provide opportunities for decommissioning wastes. However since start up of the facility in 1992 ANDRA took benefit of the flexibility of the facility to dispose of non standard wastes, as large items. These wastes could be inserted in the standard waste packages stream; in some cases dedicated structures had to be constructed as for vessel heads of PWR. Morvilliers disposal facility, dedicated to very low level waste, is an answer to the French regulation that requires the implementation of a waste zoning in nuclear facilities. It should accommodate wastes generated by decommissioning till 2030. It can accept standardised waste packages as non standard packages with a weight up to a few tens tons. Considering the forecast increase of deliveries to disposal facilities resulting from decommissioning operations, there is a need for ANDRA to propose for both facilities industrial solutions to waste generators to dispose large wastes. But the decision to dispose of large waste rather than to cut them into pieces in standard waste packages should result from an overall costs vs benefits approach shared by the waste generator and the waste management agency. This approach deals not only with costs but also with dose exposure to the workers during decommissioning operations, transportation issues and the use of space in the disposal facilities. This space must indeed be considered as a rare resource to be saved as much as reasonably achievable. (authors)