Hungary | A consortium of the companies Dömper Ltd., Subterra-Raab Ltd. and Pannon-Doprastav Ltd. is currently building what will be Hungary’s third longest tunnel near the town of Sopron in western Hungary. It is part of the last section of the M85 highway, which will create a new connection with Austria. The two tunnel tubes are made by spraying quick-
setting concrete onto the tunnel walls under pressure. The extremely alkaline excess runoff water must be neutralized before disposal. For that process, construction firms use carbon dioxide from Messer: the wastewater is pumped to a collection basin where it is injected with CO₂. This eliminates the need to use environmentally harmful mineral acids.