Robbins has received a prestigious order from contractor, Impregilo, to supply three hard rock TBMs that will be used to construct some 65km of tunnels on Iceland’s Kárahnjúkar hydro-electric project.
The order includes a 7.6m diameter refurbished machine, and two new 7.2m diameter machines. They will be fitted with Robbins 482.6mm cutters, which were successful on the record-breaking Little Calumet Leg tunnel in Chicago, US (see T&TI June 2003, p9). The first machine should be delivered later this year, and the others in early 2004.
Impregilo was awarded the US$603M contract by Iceland’s power company (Landsvirkjun) in February this year, beating off competition from Balfour Beatty and Hochtief, among others.
The project involves the construction of a 40km long, 7.6m diameter headrace tunnel, and 14km of diversion tunnels. Also included in the project is the construction of four dams, and the creation of two reservoirs – see T&TI December 2002, p6, for project details and map.
Most of the tunnels will be bored using the Robbins’ TBMs, with rest constructed by drill and blast. The rock is a basalt lava similar to that found at Lesotho, Africa.
The 630MW Kárahnjúkar hydroelectric power plant will primarily supply power to an aluminium smelting plant to be built by the American company Alcoa. Construction should be completed by the end of 2006.
