The first phase of the dismantling of the reactor vessel at Italy’s Garigliano NPP in Campania has been completed, according to Societa Gestione Impianti Nucleari SpA (Sogin). This involved removing the contaminated metal components positioned on the deflector, the upper part of the vessel – the most complex activity from an engineering and operational point of view.
The operations, carried out together with subsidiary, Nucleco, began at the end of 2023 with the flooding of the vessel and reactor channel, a necessary step to ensure maximum safety during work as water is a natural element that shields radiation. The upper part, or head, of the reactor pressure vessel was opened and Sogin began the complex dismantling activity.
Preparatory activities carried out before the removal of the vessel head included restoring auxiliary electrical, ventilation and control systems to the reactor building, as well as the circuit to flood the reactor channel. This operation was carried out under the supervision the National Inspectorate for Nuclear Safety & Radiation Protection (ISIN – Ispettorato Nazionale per la Sicurezza Nucleare e la Radioprotezione).
In the first phase, the components were removed and cut, reducing their volume, under the water with the use of a pneumatic gripper and special mechanical equipment, remotely operated with the support of high-resolution underwater cameras.
These components, weighing around 1 tonne, were then placed in two special high integrity containers for temporary storage in one of the onsite storage facilities, pending future transfer to a national repository, when it is available.
In June, Sogin laid the foundation slab for an interim storage facility at the site. The DT2 temporary warehouse will accommodate about 1,800 cubic metres of low and medium activity radioactive waste from the dismantling of the plant, pending its transfer to a national repository. Civil works should be completed by June 2025, with commissioning expected in the first half of 2026.
The programme will continue with the removal of the internals inside the vessel, for which executive design has already started, followed by dismantling of the vessel.
Garigliano NPP comprised a 150 MWe boiling water reactor that was connected to the grid in 1964 and shut down in 1982. Italy decided to phase out nuclear power in a referendum that followed the 1986 Chernobyl accident and Sogin was established in 1999 to undertake decommissioning of the nuclear facilities and siting a national waste store.
