Tournemire tunnel

This 1885 m long old railway tunnel was excavated towards the end of the 19th century. In 1988, a laboratory designed to undertake, geophysical, geomechanical and hydrochemistry studies was set up inside the tunnel. The aim of this fundamental research, carried out by the Nuclear Safety and Protection Institute, is to gain more knowledge of the way underground water moves and transports dissolved materials. It also examines the geological structure of the area. Some grey marine marl outcrops can be seen in the surroundings and are an equal mixture of clay and limestone.To get more information: IRSN