Civil engineering - Chile

El Teniente mines

The world's largest underground mine
The world's largest underground mine - © VINCI and subsidiaries

VINCI Construction Grands Projects and Soletanche Bachy are building two new tunnels at the world's largest underground mine, El Teniente, in Chile for Codelco (Corporación Nacional del Cobre, Chile).

Since the mine was opened in 1987, Soletanche Bachy Chile has been working on it almost uninterruptedly. A new seam was located a few years ago at a deeper level and it will soon replace the level currently being mined, which is expected to close in 2018. Constructora de Tuneles Mineros, a joint venture formed by VINCI Construction Grands Projets (60%), Soletanche Bachy (20%) and Soletanche Bachy Chile (20%) began work on the Nuevo Nivel Mina (new mine level) project in October 2011. To create a new mining level at an altitude of about 1,500 metres, two new 8.9 km tunnels will be built, one for personnel, the other to transport the ore. The two structures will be built in parallel and connected by 22 cross-tunnels. 

The works have an overall value of $400 million. 

"What made the difference? Our strong local roots and our engineering capabilities," says Jean-Luc Audureau, Director, Underground Works Division at VINCI Construction Grands Projets. ""We took advantage of the opportunity provided for in the specifications to submit alternative technical solutions. For example, the specifications called for the use of a TBM; we opted, instead, to propose blasting and to build six additional tunnels with intermediate openings."" What now remains to be done is to build a small town to be used by the worksite over the next three years. The project will employ 1,100 workers at the height of construction. ""We cannot recruit all the teams we will be needing on the spot because qualified manpower is scarce and in high demand. We are looking for teams outside Chile - in Latin America, Spain and Portugal. And we have set up a worksite school where we are deploying our Skill-up training programme. Knowledge transfer is important, especially for Jumbo (drilling rig) operators. We have ateam of nearly 20 instructors teaching compliance with mine safety requirements.""

Safety was a key criterion in the contract award. The consortium is using the ""(A)live on site"" safety programme, which gets worksite employees to analyse risky situations based on video footage shot in situ, and the Skill Up vocational training programme designed for machinery operators and drivers.

23.5 km of tunnels of which two main tunnels, each 8.9 km long, built at an altitude of 1,500 metres and linked by 22 cross tunnels.

2 secondary tunnels.

February 2015: handover of roads