Construction of Tailings Dam 5 (TD05) Eloise Copper Mine

Engaged by AIC Copper Pty Ltd, Exact Civil Construction delivered the Construction of Tailings Dam 5 (TD05) Project at the Eloise Copper Mine with the scope of works involving extensive excavation, embankment construction, concrete spillway creation, seepage collection drains installation, and on-site quarrying to yield drainage aggregates.

This Project presented unique challenges that required precise execution and expertise, specifically in relation to the strategic movement of materials using scrapers and articulated dump trucks to complete the starter embankment once the HDPE liner was installed, ensuring the integrity of the structure.

To address seepage concerns, seepage collection drains were installed on the downstream faces of the existing tailings dams, namely TD01, TD02 and TD04, this approach allowed seepage water to be efficiently collected and directed. To achieve this, aggregate processing and crushing were completed on site for the aggregate used in the drains. Collected seepage water was channeled through pipes and pumped to existing return water ponds and was a crucial aspect of environmental management.

Construction of the drains were completed in a two-step process, using an excavator to shape and subsequently line the drains with 300mm rock, ensuring the effectiveness of the drainage system. Additionally, construction of the emergency spillway located on the starter embankment downstream wall was entrusted to specialist Subcontractor, with concrete supplied by Eloise Copper Mine from an onsite batch plant to ensure quality and reliability of supply.

Efficient material management was a priority with excess material transported to two (2) stockpile locations. The first location is situated atop TD03 which is earmarked for future use for the Eloise Copper Mine when capping TD01/02 when the dam reaches its maximum deposition level. The second location is positioned to the south of TD05 and will play a vital role in mine rehabilitation and potential upstream raises on TD05.

‍Key Achievements

‍Construction of the TD05 Project required several challenges and solutions, demonstrating the problem-solving capabilities of Exact Civil Constructions and our commitment to delivering our projects to our clients satisfaction. One notable recommendation saved AIC Copper $26,000, through a proposal to the Design Engineer to modify the design for the southern drain. The advice involved leaving existing material in place, as it surpassed the quality of the proposed liner material. This proactive solution reduced expenses and ensured the use of superior materials.

A new design for the dam floor was also provided to the Design Engineer which optimised the shape to not only meet Project requirements but expedite the return of tailings water to the Mill. This adjustment allowed for a 12-month acceleration of tailings water return, delivering substantial savings to AIC Copper and enhancing operational efficiency.

A key challenge involved anchoring the liner against the existing tailings dam without compromising stability, the Exact Civil Construction Project team devised a practical and effective solution, which was accepted by the Client and Design Engineer. This collaborative approach ensured there were no delays in the construction process, avoiding the need for a time-consuming redesign of the anchor trench.

The Project stands as testament to the problem-solving skills, collaborative approach, and dedication of Exact Civil Construction to achieving our clients needs. We prioritise innovation and efficiency to ensure that we deliver exceptional results and substantial cost savings while maintaining the project critical path.