Carrapateena Tailings Storage Facility Project

Client: OZ Minerals
Date: 2019

Exact Contracting were engaged to construct Stage 1 and 2 of the cross-valley tailings storage facility (TSF) at the Carrapateena copper/gold mine, northeast of Port Augusta, South Australia.

Stage 1 of the TSF consisted of three primary embankment structures – decant dam embankment, TSF embankment and causeway totalling approximately 500,000m³ of imported general fill, select fill (crushed/screened) and clay.

Pipeworks were also completed in conjunction with earthworks including a gravity decant line and multiple seepage collection lines, totalling approximately 4.5km of butt welded pipe and associated fittings/valves.

Stage 2 of the TSF Facility provided a buttress to the existing dam that is sufficient for the proposed total design life.

Scope of works for Stage 2 included:

• Construction of a 5km haul road from mine waste stockpile to TSF facility.
• Load and haul of approximately 1,600,000 m³ of waste material to from the mine waste stockpile to the embankment footprint.
• Screening and installation of armour rock and fine material for the downstream and upstream faces of the embankment.
• Installation of underground seepage pipe network with extraction sumps.
• Installation of Bituminous Geomembrane and ballast tubing in the upstream face of the embankment.
• Installation of precast decant towers.
• Installation of material over in-situ tailings as a second stage lift to the decant causeway.