Superphenix - Creys Malville. Strategy for dismantling the reactor block

This document describes the operations to be performed to dismantle the SPX reactor vessel. The first studies for dismantling the Superphenix power station reactor block have defined the broad outlines of the dismantling strategy an proposed a certain number of orientations. The period covers SPX reactor block dismantling, from the end of fuel unloading until complete dismantling of the installations. Two dismantling methods have been considered: -underwater dismanting (Reference scenario); - dismantling with the structures covered with sodium carbontae (Alternative scenario). In both cases, dismantling will be carried out 'from the top' through the reactor slab and will be preceded by a preliminary phase of sodium retention reduction followed by a phase of vessel internals carbonation. The dismantling studies are undertaken with a view to the work lasting eight years maximum. The work prior to reactor dismantling will last from the end of 2011, after sodium draining from the reactor, until the end of 2013. At present, the Superphenix dismantling work is planned to begin in 2014 and continue for a period of eight years. All the installations should have been dismantled by 2025. (author)