Spanish grid operator Red Electrica has awarded a contract to an undisclosed company for the provision of geophysical, UXO and geotechnical services along a corridor of approximately 345 kilometers between Spanish mainland and Mallorca Island, in the Mediterranean Sea.
Red Electrica spokesperson said the company will not disclose the contractor at the moment, but it might decide to do so after the survey starts mid or end of September.
The purposes of the geophysical and geotechnical investigations are the determination of the detailed seabed conditions and stratigraphy with detailed characterization of the materials in the surface and subsurface soil layers in order to inform the installation of submarine cables.
Mallorca already links to the Spanish mainland via COMETA (aCOnexión MEditerránea Transporte Alta tensión) subsea interconnector, developed by Red Electrica, also known as the Majorca–Valencia interconnector and the Romulus project).
Red Electrica also recently completed the electricity interconnection of all the Balearic Islands following the commissioning of the new link between Menorca and Majorca .
The geophysical investigation shall include both surface and subsurface survey (sub-bottom profiling) in water depths ranging between 0 and approximately 1,600 meters .
The purpose of the UXO survey is to ensure an As Low As Reasonably Practicable (ALARP) UXO risk at each anticipated geotechnical location to be investigated during the subsequent geotechnical survey. The execution and the scope of the UXO survey is subject to the results of the ‘UXO risk assessment and mitigation strategy’ study.
The geotechnical investigation will consist in CPTs, vibro cores, piston cores, rock cores and similar.
It includes the collections of quality samples of soil and rock for tests onshore and offshore to determine physical and mechanical properties, to support the interpretation of the geophysical data.