Swedish mining and smelting company Boliden has revealed plans to invest €44m to extend the life of Tara zinc mine in Ireland and expand the capacity of its tailings dam.
The exploration identified a new mineralisation with an inferred mineral resource of ten million tonnes.
Tara represents for half of Boliden’s production of zinc concentrate.
Successful exploration has led to the discovery of a new mineralisation in Tara Deep, and a capacity extension of the tailings dam, which presently limits Tara’s lifespan, has been decided.
The new tailings dam will have enough capacity for production at present levels until 2026.
The investment totals €33m and is conditional upon receipt of the required official permits. It is based on mining until 2023, but the new mineral resources offer additional potential.
Construction of an exploration drift to the new deposit at a cost of €11m has also received approval.
Boliden Mines president Mikael Staffas said: “Tara’s exploration work in the last few years has been successful, and the capacity of the tailings dam is now limiting the life-of-mine to 2020.
“New exploration successes, increased productivity, and high zinc prices make extending the mine’s lifespan a profitable option, so we have decided to expand the tailings dam with a capacity until 2026.”
The new deposits found at the mine exhibit inferred mineral resources that totals ten million tonnes, offering a zinc grade of 8.5% and a lead grade of 1.8%.
Located at depths of 1,200m and 1,900m, the structure of the mineralisation is more complicated than earlier deposits.
In addition to identifying the Tara Deep deposit, successful exploration in the existing mine has helped replace almost the entire year’s production in the mineral reserve.