Deutsche Bahn has announced an extension of Implenia contract to build the Albvorland tunnel on the new 60km Wendlingen to Ulm rail line.
The extension was announced in the Official Journal of the European Union (OJEC) and adds €53M (£47M) to bring the value of the contract up to €430M (£381M).
According to the statement in OJEC, the extension is necessary after several technical changes were required based on ground conditions to ensure the stability of the tunnel structure.
The Albvorland tunnel is a twin bore tunnel that is 8km long and 11m in diameter, which Implenia first started working on in early 2016. The project is due to be completed in 2020.