The commodity markets may have taken a hammering over the last year but one of the new breed of TBMs from Seli, a Compact DSU, is being assembled in Chile to help a mining company probe how to most efficiently exploit a new ‘world class’ copper deposit.

The mining company and customer, Anglo American Chile, said at the end of July that the planned exploratory tunnel would cost approximately US$60M and take two years to excavate. The earlier estimate was just over a year (T&TI, March, p12).

Seli’s simpler, shorter shield is a 4.5m diameter unit and will be used to bore the tunnel. To handle variable ground, the machine can also install rock bolts, steel sets and wire mesh.

The TBM is the key part of the US$14.4M design and supply package awarded by the customer, which also includes backup, equipment plus provision of specialised workers and technical assistance.

A JV contractor, Dragados-Belsaco, will use the Compact DSU – the manufacturer’s second to be made – to bore just over 8km at the Los Sulfatos prospect, near Los Bronces mine, in the Andes about 65km north east of Santiago. Los Bronces is an open pit copper and molybdenum mine.

Anglo American said last month that early exploration of the prospect has indicated a significant deposit of an estimated 1.2bn tonnes, containing about 17.5M tonnes of copper.