The council has awarded a joint venture between Geoconsult España Ingenieros Consultores, Investigación y Control Calidad and Audingintraesa a service contract worth €1.8m to study the technical and environmental requirements of the project. The report is due to be finished by the end of 2019 so tenders can be invited for the works at the beginning of 2020.

The study will be conducted by a multidisciplinary team experienced in geology, geotechnics, structural calculation, railway and underground layouts, topography, urban planning, historical heritage, archaeology, environment, noise and vibration and prevention of material hazards.