In autumn 2011, Edilmac built a vertical well for its consortium member Cordée Mont Blanc using the “Raise Boring” technology. The well, 77m-deep and with a diameter of 1.84m, is located in Pointe Helbronner on the Mont Blanc massif at about 3500m above sea level. The special feature of this perforation is the height at which the drilling was conducted, a record for the European continent.
Our intervention was required to create the space necessary for a lift to replace the third section of the current cable railway connecting the bottom of the valley with Pointe Helbronner. As the system was obsolete, it meant that excursionists had to wait in long queues to reach the top.
To access the building site we installed a “Blondin” cableway and two cranes, placed by using helicopters suitable for works at high altitude. This equipment could not lift more than 4 tonnes, so it was necessary to disassemble the parts of the RBM 61 machine and subsequently reassemble it on the working site using one of the two cranes. This proved to be a fairly complex operation due to the strong winds at high altitude that caused the equipment to swing violently. Moreover, due to ice penetration in the granitic rock, there were a few issues in conducting the drilling, as well as the pilot hole.
However, thanks to Edilmac team’s professional approach and preparation, the job was completed earlier than expected and without any particular problems, once again highlighting the company’s distinctive quality levels and expertise.
