The undersea cable routes were designed to minimise interference with the Posidonia oceanica habitat at the Terra Mala landing site (Cagliari). Moreover, in order to compensate for any residual damage to the habitat, Terna will plan and implement the Posidonia oceanica transplantation, in agreement with MASE, the Italian Ministry of the Environment and Energy Security (Directorate General for Natural Heritage and the Sea), and ISPRA, the Italian Institute for Environmental Protection and Research, according to the standards defined in the European manual LIFE SEPOSSO. The activities consist of harvesting the cuttings and replanting them in areas specifically identified by scientific experts in the field. Subsequently, the transplantation process will be monitored for at least five years, to verify that the cuttings have been correctly rooted and the habitat has been properly restored. Posidonia oceanica is an aquatic plant, typical of the Mediterranean seabed, where it is widespread and is considered an ecological resource of great importance, as it forms underwater prairies that play a crucial role in protecting the coast against erosion. Read more about Terna's Posidonia oceanica transplanting activities in the Lightbox article

Terna has already conducted this intervention, before laying the undersea cable connecting the island of Elba to peninsular Italy: to protect biodiversity, before laying the cable, Terna transplanted about 53,000 cuttings of this plant in an 1,650 m² area in the Gulf of Follonica.

At the Fiumetorto landing area, in the municipality of Termini Imerese (Palermo), Terna planned the undersea cable routes to minimise interference with the existing habitat. Terna started an experimental transplanting process of Cymodocea nodosa - an aquatic plant native to the Mediterranean Sea that plays a fundamental role in the marine ecosystem. It is now safeguarded by the European Union, as it protects the coastline from erosion, preserves biodiversity, and captures CO₂. The relocation project has an experimental nature, as it has never been carried out for this species on such a large scale and in the open sea before now. Every step of the process was supervised by experienced and qualified Terna personnel, in cooperation with CoNISMa and ECON s.r.l., and shared with the italian Ministry of the Environment and Energy Security, with ISPRA’s support (ISPRA is the Italian Institute for Environmental Protection and Research). The transplantation process involves the reintegration of about 20,000 cuttings in 1200 square meters of seabed, at a depth of 10 metres. Afterwards, a five-year environmental monitoring plan will begin, to monitor the operation's success over time, through a sampling protocol. The intervention will include a 6-year study and analysis project, and will lead to results of high scientific and popular value, contributing to enrich the little literature on the subject to date. Find out more

To ensure the protection and respect of the territory, in the areas of the future converter stations, Terna technicians and experts carried out a preliminary hydro-geological risk assessment during the project authorisation phase.

The rainwater collection and disposal projects, both inside and outside the station, are being drafted. On some sites, rolling tanks upstream of the discharge into the final destination will be required in some sites, to ensure the hydraulic invariance principle (i.e., when the run-off resulting from an area being drained remains unchanged after the area's land use is altered). These solutions will be shared with and approved by the Bodies involved before being implemented.

Terna will design the future converter stations with the goal of minimizing their visual and environmental impact. By planting tree species and using suitable covering materials, the structures will be integrated into the surrounding landscape to create an overall sustainable aesthetic, respectful of the environment. Terna will resolve on such choices also through the participation of Local Bodies, so as to ensure that the solutions adopted are in line with the characteristics of the territory and the expectations of local communities.

Terna will use the so-called TOC technique - remote-controlled or controlled horizontal drilling - for laying the undersea cables at the landing sites. Through this technique, the cable pipeline can be bridged over any Posidonia oceanica meadows, thus overriding the project's impact on the shoreline and ensuring the necessary protection of the electrical connection in the event of coastal erosion. In addition, the cable depth will be between 4 and 8 metres at the foreshore, while undersea cables will be placed at depths of more than 10 to 15 metres, as soon as they exit the drill pipe. Read more about undersea cable-laying activities in the Lightbox article

With the support of the Department of Cultural Heritage and Sicilian Identity and the Superintendency of Palermo, Terna started the preventive investigation and archaeological excavation activities in the Termini Imerese (Palermo) area, where the conversion station will be built. During the preliminary survey for sites of archaeological interest, as part of the project planning phase, a section of conduit - mostly underground that can be traced back to the Cornelius Aqueduct from the Roman period was discovered. In agreement with the Municipality and the Superintendence, part of the Cornelio Aqueduct conduit will be reconstructed in a special area within Termini Imerese, as identified with all the institutions involved. This is a unique opportunity for residents, who will be able to enjoy the findings of the archaeological investigations carried out, through a special exhibition route in the newly identified area. Find out more

Terna has already carried out this kind of initiative for the new high-speed Naples-Bari electrical connection: to enhance the great archaeological heritage discovered during excavation works for the future electric substation in Amorosi (Benevento), Terna set up and inaugurated the multimedia exhibition dedicated to the discoveries made in the Telesina Valley. The initiative is mainly aimed at primary and secondary school children. Read more about Terna's preventive archaeology activities in the Lightbox article

In 2023, Terna carried out some major environmental reclamation works in the former fruit and vegetable market, in San Nicola Varco (Eboli, in the Salerno province), where the future converter station will be built. Specifically, Terna conducted a massive intervention to remove abandoned waste and asbestos-containing materials, in a place that was in a dreadful state of abandonment and negligence. The works - carried out with the help of qualified companies and suppliers, in agreement with the competent authorities - lasted less than a year, and brought to light over 4,000 tons of waste, the majority of which classified as hazardous. Moreover, some old structures present in the area were demolished during the reclamation works.

Terna carried out a similar intervention in Caracoli (Termoli Imerese, in the Palermo province), before beginning the works for the future converter stations in the East section.

Lastly, Terna started asbestos reclamation and waste removal works also in the municipality of Selargius (Cagliari), where the future converter station of the West section will be constructed.