In March 2023, the wicking program in Pit 3 was successfully completed. This achievement involved inserting approximately 41,000 wicks into the tailings of Pit 3. 

With each wick ranging between 25-40 meters, these wicks would cover a distance equivalent to that from Darwin to Alice Springs when laid out flat. Wicking represents a significant milestone for ERA. It enables water to be extracted from the tailings material to support the consolidation of tailings, which enables Pit 3 rehabilitation works to continue. ERA partnered with Ventia for their experience in environmental remediation and directional drilling capability.

The project presented challenges, as acknowledged by Jason Gaul of Ventia, who highlighted “there were a range of safety challenges for the team to consider. These included working around tailings, acidic water, moving plant equipment in tight spaces, and challenging environmental conditions such as rain, lightning, and heat.” Collaboration was key, as emphasised by Ranger Rehabilitation Project Director, Bernard Toakley: “ERA and our contracting partners worked cohesively to establish excellent teamwork, addressing the challenges encountered during the wicking project. Each challenge was significant, demanding a strategic approach and strong collaboration among the key parties involved in the project’s delivery.” Due to a covering layer of water up to five metres in depth over the tailings, a specialised delivery method was required to achieve success.

A novel, unique barge system was designed and constructed to allow the installation of wicks from the water’s surface. The works required an onsite workforce of over 70 personnel and over 101,000 hours worked on site to successfully deliver the project. Despite the complexity and challenges faced, including submerged obstructions, poorly consolidated tailings, weather delays during the wet season, and early logistical challenges, the collaboration between ERA, Ventia, SWAMOJV, Polaris Marine Operation, and ERA’s Integrated Project Management Team has facilitated the efficient and safe completion of this critical phase in the Ranger Rehabilitation Project. Now that the tailings material has consolidated, the covering layer of water has been removed to the Ranger Water Dam, allowing the tailings to dry for the commencement of initial capping, including the installation of geotextile fabric. The wicking program played a significant role in the rehabilitation project, serving as a critical activity to complete rehabilitation. The performance of the wicks exceeded expectations, leading to a substantial reduction in the tailings surface across Pit 3.