Project Information: Tunnel for the double track Ariz – Basauri branch of the Bilbao Metro. Includes wells equipped for raise boring, jet grouting treatment, screens, pile driving, etc. The length of the worksite is about 1.5 miles (2.37 Km) and runs through an urban environment. Works comprise the construction of two underground stations in caverns measuring 110 m in length and 190 m2 each section, where concourses, platforms and technical rooms will be built. They also include the implementation of access to the stations, such as emergency ventilation systems and ventilation systems under platforms. 11,230 m3 of shotcrete, 70,000 kg of steel fibre, 90,000 ml of Swellex rock bolts, 500,010 kg of roof trusses, 221,000 m2 of electro-welded wire mesh, 12,000 ml of micro piles.