Decommissioning starts on Italian reactor

Decommissioning of the nuclear island of the Trino Vercellese nuclear power plant in Italy is now under way. The work is expected to take twelve years to complete at a total cost of €234 million ($303 million).

Decommissioning of the nuclear island of the Trino Vercellese nuclear power plant in Italy is now under way. The work is expected to take twelve years to complete at a total cost of €234 million ($303 million).  

Trino will be the first Italian nuclear power plant to be fully decommissioned (Image: Sogin)

Trino Vercellese - comprising a single 270 MWe pressurized water reactor - was Italy's first commercial nuclear power plant. Its construction began in 1961 and the plant started generating electricity in 1964. As a result of a referendum held in 1987 in the wake of the Chernobyl accident, Italy decided to shut down its four nuclear power plants. Trino was subsequently permanently shut down in 1990. State-owned Societa Gestione Impianti Nucleari (Sogin) took over ownership of the plant from utility Enel in 1999 and is responsible for its decommissioning.

Work so far

So far, the main decommissioning activities at Trino site have concerned:

- the demolition of the cooling towers and the weather tower;
- the decontamination of steam generators;
- the dismantling of the buildings that housed the emergency diesel generators;
- the removal of asbestos;
- the dismantling of components in the turbine building;
- and, the removal of non-nuclear auxiliary systems.

While a certain amount of decommissioning work has been under way at all four Italian plants, Trino became the first plant to obtain a decree for its complete decommissioning. This was approved in early-August 2012 by the ministry of economic development.

Sogin said that it expects to complete the decommissioning of Trino in 2024, when it should be returned to a greenfield site and the land released for new development. The total investment to return the site to unrestricted use is expected to be about €234 million ($303 million).

Some €86 million ($111 million) of that has already been spent of clean-up work related to the Trino plant: €34 million ($44 million) has been spent on decommissioning activities, while €52 million ($67 million) has gone towards waste storage. A further €148 million ($191 million) will be spent on the plant's decommissioning.

Sogin expects the dismantling of the Trino plant to generate some 214,000 tonnes of waste, of which only 2000 tonnes will be radioactive waste. This radioactive waste will be stored on-site, awaiting shipment to the national repository. The site of this facility has yet to be determined.

The remaining decommissioning work will be carried out in four phases: modifying existing temporary storage facilities; construction of facilities to support the decommissioning work; dismantling of the systems and components within the nuclear island; and finally, completing site remediation.

Over recent years, Italy has revisited the idea of using nuclear power, and a change in government policy in 2008 led Enel to propose the construction of four large reactors, in cooperation with EDF. However, in a national referendum in June 2011, Italians voted overwhelmingly against a return to nuclear power.

Researched and written
by World Nuclear News