Offshore Transportation, Installation and shore approach for the Cassiopea Project

Project summary

The CASSIOPEA Project involves the installation of a new underwater production system, a new onshore facility and improvements to an existing platform named Prezioso. It constitutes a strategically important infrastructure for Italy's energy supply. Gas extraction from offshore fields is carried out through a fully subsea development, characterized by zero emissions and no visual impact on the sea surface. The extracted gas is then transported through a 60-kilometer subsea pipeline to the modern treatment facility within the Gela refinery area (Sicily). The onshore landing re-establishes an existing, now disused, structure located at east of the refinery jetty. From here the gas is finally injected into the national distribution network actively contributing to the country's energy supply. 

The constant pursuit of highly sustainable solutions has led to the identification of project optimization with the following key advantages: 

• Environmental Sustainability: Zero emission impact, no direct discharge into the sea, virtually no emissions (carbon neutrality). 

• Territorial Enhancement: Investments in the area, positive impacts on employment, and the enhancement of the local economy both during construction and operation. 

• Synergies with Gela Refinery and Industrial Area Redevelopment: remediation and reuse of disused areas and coaction with existing facilities and utilities. 

Project details

The activities carried out by SOCOTEC Italia were conducted through three targeted survey campaigns aimed at various characterization objectives: geotechnical, environmental and for the seabed. As well the company have done the detection of unexploded ordnance and the assessment of the submerged part of the Prezioso platform. These specific surveys included: 

• UXO AND PRELAY OFFSHORE SURVEY: this campaign focused on the detection and management of unexploded ordnance in offshore areas. 

• ENVIRONMENTAL CHARACTERIZATION: this phase involved the environmental characterization of the area of interest. 

• GEOPHYSICAL INVESTIGATION: geophysical surveys were conducted in offshore and nearshore environments to acquire data on the nature and morphological characteristics of the seabed. 

• ASSESSMENT OF PREZIOSO PLATFORM & 3D CLOUD OF SUBMERGED JACKET: activities to assess the thickness the Prezioso’s wall platform and activities to create a three-dimensional model of its submerged part were carried out with the aim of ensuring safety and facilitating maintenance operations on the