Thunderbox Expansion Project

Scope of Work

Northern Star Resources (NST) awarded GR Engineering the design, procurement, construction and commissioning of the expansion of the processing facilities at their Thunderbox Operation (TBO) from 2.9 Mtpa to 6 Mtpa. The TBO is located approximately 45 km south of the town of Leinster and approximately 330 km north of Kalgoorlie. GR Engineering had previously delivered a Paste Fill Project for Saracen Mineral Holdings (former owner of the Project) in 2020 at the TBO. 

The Project consisted of new and upgraded ore processing facilities to increase throughput of the existing TBO Process Plant to 6 Mtpa. Works included the installation of a new crushing circuit, stockpile and reclaim area, milling and gravity circuit, pebble crushing, leach, elution, tailings, reagents and services. 

This Project was unique for GR Engineering due to the size of the installed SAG mill. The SAG mill is an 18 MW dual pinion drive and to date the biggest mill installed by GR Engineering. The new circuit was successfully commissioned and handed to Northern Star operations in September 2022. .


Project Fact Sheet

Thunderbox Expansion Project

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  • Client Northern Star Resources Limited (ASX: NST)
  • Award Date April 2021
  • Completion Date September 2022
  • Location Leinster, Western Australia
  • Project Type Greenfields and Brownfields, EPC design and construct