The Peak Downs Mine (PDM) is a large open cut coking coal mine and is Australia’s biggest coal mine by recoverable coal reserves, located 31km SSE of Moranbah, Queensland. The PDM Long Term Tailings (LTT) Project was commissioned in response to significant tailings dam failure incidents, and to progress an alternative option to conventional “wet” tailings storage facilities (TSFs) for the handling and storage of coal tailings. DRA has been involved with the PDM since 2020, supporting BHP through early contracting involvement (ECI) in the project's Definition Phase Study through to the current execution phase.

The PDM LTT project will install a mechanical tailings dewatering facility using Belt Press Filters to dewater the tailings stream. The filter cake will be combined with the coarse reject material and trucked to the mine for disposal in the pit void via co-emplacement with overburden / waste rock. This new process will enable PDM to close the existing conventional ‘wet’ TSFs, reduce the risk of tailings dam failure and provide a more sustainable future including reduced costs for mine rehabilitation and closure.

DRA has been involved with the PDM since 2020, supporting BHP through Early Contractor Involvement (ECI) in the project’s Definition Phase Study (DPS) and culminating in the current project execution phase.

Scope of Work
DRA has been elected by BHP as the preferred partner for the design, engineering and construction of the LTT facility. The ECI phase allowed DRA to develop an innovative process design and optimised site layout. The award follows ongoing collaboration between DRA and BHP to confirm the Project scope and budget.

The LTT scope comprises of a mechanical dewatering facility and associated infrastructure at the PDM to produce “dry” tailings and a mixed product reject material for co-emplacement. The scope is to be delivered as 2 Separable Portions:

  • Separable Portion 1: Coarse Rejects System – Includes modifications and additions to the existing coarse reject system to extend materials handling to the new Mixed Plant Rejects Bin.
  • Separable Portion 2: Tailings Treatment Facility – Balance of scope including Floc Prep Belt and Plant Press Filter Building.
    The Project will be delivered jointly by DRA and its subsidiary, G&S Engineering Services, providing an integrated ‘end-to-end’ execution approach. DRA will provide project management, engineering and procurement services with G&S to lead construction activities.


Key Accomplishments
DRA was initially engaged in a competitive dual ECI and throughout this process built a strong ongoing relationship with BHP project and site teams. Throughout this time our team demonstrated the winning capabilities of both DRA and G&S including innovative and cost-effective design and project delivery. This serves as testament to DRA’s client focused approach and long-term support for BHP and the PDM Project.