- ClientTERNA
- Year 2010/2011
- Sectors Energy Infrastructures
- Services - Environmental Impact Assessment (EIA)
- Environmental Implication Assessment
- Preliminary Archaeological Assessment
- Landscape studies
- Landslide risk assessment and remediation
- Noise Studies and Mitigation plans - Stage of Activity Approval of Ministry of Environment with Decree DVADEC n. 2012-0000739 of 20th December 2012
Environmental Impact Study of the 220 kV terrestrial and submarine cable interconnection between Italy (Marina di Ragusa) and Malta (Maghtab)
PROJECT DESCRIPTION
Malta-Sicily interconnector is included in the Trans-European Energy Network (TEN-E), and, with its 120 km, is one of the longest high-voltage power cable in alternating current.
The project involved the construction of a high-voltage AC power cable between Italy and Malta, including a submarine three-conductor connection of about 120 km with a voltage of 250 MVA.
As regards the Italian section, the 220 kV cable consists of about 26.5 km of submarine three-conductor interconnection between Italian territorial waters and the Sicilian shore and 19 km of underground connection from Ragusa existing power substation to the landing point of the submarine cable (Marina di Ragusa).
For the construction of the ground /sea joint section in Marina di Ragusa landfall, it was adopted the Horizontal Directional Drilling (HDD) technique. This technique ensures the cable landing does not occur in the presence of drilling fluids but in presence of biodegradable materials compatible with the environment.
PROJECT CHARACTERISTICS
During the work the most innovative and environmental-friendly technologies were implemented in order to minimize the impact of the marine cable installation with respect to possible coastal erosion and Posidonia Oceanica (a seagrass species endemic to the Mediterranean Sea) preservation.
In case of rocky seabed with Posidonia meadows, the cables cannot be anchored and the technique of cast-iron shells (CIS - Cast Iron Shells Installation) is required. This allows the protection of the cables while their increased weight prevents their movement.
Capjet technique, with silting-up through water jet machines, was the choice regarding sandy bottoms and represents the state of the art in minimizing the phenomenon of suspended sediment.
Several studies concerning environmental themes were developed, such as:
• Careful examination of environmental constraints and protections;
• Analysis of project alternatives;
• Survey of areas of natural interest subject to environmental protection;
• In-depth study of surface and groundwater flows;
• Analysis of land use and ecosystem units;
• Evaluation of the project interference on the marine habitats;
• Determination of seagrass presence and characterization of marine sediments;
• Assessment of absolute and relative archaeological risk;
• Mapping of underwater archaeological finds;
• Identification of receptors suitable for acoustic and atmospheric emission study and electromagnetic field evaluation;
• Assessment of construction phase emissions;
• Environmental Monitoring Plan.