Ernest Henry Mine - Project Completion Ahead of Program

Ernest Henry Mine, owned and operated by Evolution Mining, owns and operates an underground mining and processing operation 38 kilometers north of Cloncurry in northwest Queensland for the production of copper-gold concentrate.

In February 2024, Evolution Mining awarded Exact Civil Construction to undertake the provision of a Tailings Storage Facility (TSF) upgrade (Buttress Works).

The mining operations is reliant on the TSF for disposal of process waste. The current TSF was nearing capacity and required earthworks for additional bracing of material (Buttress) to ensure compliance.

The project involved clearing and grubbing, foundation preparation, topsoil stripping and source site preparation, extension of existing spillway and load haul over 5km of 500mm – 1000mm diameter rock buttress material

Seepage blankets, V-notch drains and filter drains were also installed to assist in management of potential seepage. Filter rock was crushed and screened onsite by Exact.

This was achieved using all of Exact Civil’s plant and machinery and included a team of 10 x Cat 777 Dump Trucks and 250t Excavator, 3 x Cat D10 Dozers, Cat D11 Dozer, Cat 740 Water Trucks, Komatsu WA 900 Loader and a team of Cat 16H Graders for haul road maintenance and trimming works. We also used 35t Excavators and 740 Articulated Dump Trucks for the detailed works. An extensive workshop and office facilities were installed and a team of 10 fitters and mechanics ensured great machine utilization.

GPS machine control on all Graders, Excavators and Dozers ensured the design lines were kept in compliance throughout the construction.

Detailed daily monitoring of production using Exact Civils integrated project management system ensured the project was delivered 6 weeks ahead of schedule.

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Project Components‍

- 3.2 million m3 of buttress rock installed and trimmed to design

- Spillway constructed to match lift of TSF

- 40 ha of clearing, grubbing, stockpile clay, clear waterway edges and foundation preparation clay liner

- Crushed and screened 100,000 t of filter rock

- Installation of settlement plates to monitor embankment settlement

- GPS control of earthmoving and trimming plant

- Strict compliance to design requirements of settlement periods between lifts

- Toe Seepage Blanket, channel formation and V-Notch Re-Install

- Topsoil strip in preparation of source material

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