On 5 January 2021, the Carta nazionale delle aree potenzialmente idonee alla localizzazione del deposito nazionale (Cnapi) was published. This is a map used to identify the most suitable area to host the surface infrastructure where low-level radioactive waste, currently stored in dozens of temporary repositories scattered across Italy, can be safely housed. We are talking about nuclear waste produced during the operation of nuclear plants (subsequently decommissioned in 1987 following a referendum), the dismantling of those plants themselves, as well as the day-to-day activities of nuclear medicine, industry and research.

The map identifies 67 sites divided across seven regions (Piedmont, Tuscany, Lazio, Puglia, Basilicata, Sardinia and Sicily), selected on the basis of a series of criteria drawn up by the National Inspectorate for Nuclear Safety and Radiation Protection (Isin). The general table attached to the Cnapi also lists the municipalities concerned: the most likely candidates appear to be in two areas in the province of Turin (Caluso and Carmagnola), five in the province of Alessandria (including Bosco Marengo and Novi Ligure) and in the province of Viterbo.

A matryoshka-style infrastructure for nuclear waste

What will the repository look like? The dedicated portal depositonazionale.it explains: it is a set of engineered barriers nested one inside the other. First, the conditioned and compacted waste (conditioning involves encapsulating solid waste, or solidifying liquid waste, in cement or glass) will be sealed inside steel drums filled with cementite. The drums will in turn be enclosed in reinforced concrete boxes, and all the boxes — around one hundred of them — will be arranged in a large surface-level basin, also made of concrete. This basin will finally be covered with a layer of soil and a grass surface.

The repository will occupy 110 hectares, but the area set to host it will measure 150 hectares because a 40-hectare technology park will also be built: by design, this is an applied research and training centre in the fields of nuclear decommissioning, radioactive waste management and radiation protection, as well as environmental protection.

The total investment for the construction of the national repository and technology park will be approximately 900 million euros (which, including associated works, could reach 1.5 billion euros) and will be funded by the A2RIM tariff component (formerly the A2 component) of the electricity bill, which already covers the costs of decommissioning nuclear plants today.

Municipalities and regions don't want to host nuclear waste

The siting process has only just begun and, alongside the publication of the map, the public consultation phase was launched: within 60 days, local authorities and stakeholders may submit their observations; within 120 days of the start of the public consultation, a national seminar will be held. After these "exchanges" with the local communities, the Ministry of Economic Development will need to approve the final version of the Cnapi.

The publication of the map is part of the nuclear plant decommissioning activities entrusted to Sogin, a public company held by the Ministry of Economy and Finance, which is tasked with locating, designing, building and managing the permanent national repository, a surface-level engineering infrastructure. The legislative decree of 2010 that charged Sogin with decommissioning stipulated that the Cnapi should be published by August 2015.

Five and a half years late, clearance from the Ministries of the Environment and Economic Development finally arrived, but the only unanimous response has been a chorus of "no"s: on top of the delays, criticism from regions and local authorities has piled up. Puglia and Basilicata, for example, have joined forces in protest: in their area, building such a repository is unthinkable, as "these are areas of particular natural value, which are part of parks or are candidates to become so." The municipal council of Matera is ready to formalise its rejection, while the mayors of the Bari area have threatened to take to the streets.

Sardinia is also opposed, having convened a regional council session to reiterate its negative opinion, while in Sicily president Nello Musumeci announced a task force of experts to challenge Sogin's choice. "An unacceptable proposal, in a Unesco World Heritage territory with a strong tourism vocation," was the reaction of the mayors of the Val d'Orcia and the Val di Chiana, with the mayors of the thirteen municipalities of the Tuscia area of Viterbo echoing the same sentiment.

The case of Piedmont's nuclear waste

"I find it absurd that a decision of this magnitude was taken without even the minimum consultation with the region and the mayors of the affected areas," declared Piedmont's governor Alberto Cirio, offering support to the selected municipalities in order to "send Rome detailed observations to demonstrate that their respective territories are unsuitable to host nuclear waste."

Piedmont is the region that already hosts the most waste of all: 75 per cent of the radioactive activity from nuclear waste is concentrated in the area where the three nuclear sites of Saluggia, Trino Vercellese and Bosco Marengo are located. In Saluggia alone, a small village in the province of Vercelli, 2.3 out of 3 GBq are concentrated (the becquerel is the unit of measurement for the activity of a radionuclide) and numerous releases of radioactivity have contaminated the shallow groundwater. The values are low, measured at wells where the water is not intended for drinking. But the levels are nonetheless defined as a "strong environmental indicator" by Arpa.

One thing is certain: the waste cannot remain where it is now, due to hydrogeological risks and proximity to watercourses. In Saluggia, where the majority of the waste is concentrated, there are three hot spots: the Eurex, a plant being decommissioned that was used for reprocessing irradiated fuel, the Avogadro repository and the Sorin repository. The latter two are operational (not for production purposes but for activities related to securing the waste) and house highly radioactive waste.

Where the high-level nuclear waste is located

The waste is not found only in Piedmont, but is scattered across various regions: the old four power stations at Trino Vercellese (Vercelli), Caorso (Piacenza), Latina and Garigliano (Caserta); the former Fabbricazioni nucleari plant at Bosco Marengo (Alessandria); the three fuel-cycle research facilities at Saluggia (Vercelli), Casaccia (Rome) and Rotondella (Matera); and various research centres.

In total there are 90,000 tonnes of waste to manage, not counting what is added each year from medical and industrial activities — around 140 tonnes per year — of which the national repository will accommodate 75,000 tonnes. The remaining portion, representing 6 per cent of the total, consists of intermediate- and high-level waste, for which a deep geological repository is required.

Since sites of this kind are difficult to identify and require decades to build, it is planned that the surface-level national repository will also host a long-term temporary storage facility where the most hazardous waste can be held while awaiting another solution.