DeGrussa

The DeGrussa Operation is situated near Peak Hill in Western Australia's Mid-West region, approximately 900 km northeast of Perth. This extreme remoteness creates critical supply chain vulnerabilities: all consumables, reagents, and heavy equipment must traverse long-haul routes via the Great Northern Highway. The semi-arid terrain, characterised by flat to undulating scrubland, imposes strict logistical planning cycles and demands robust inventory buffering strategies from all B2B vendors operating in this corridor.

DeGrussa has formally transitioned from active production into a care and maintenance phase following cessation of underground extraction in October 2022 and processing in May 2023. Sandfire Resources retains 100% ownership. The processing plant was divested to Boab Metals Limited in April 2025. Current B2B demand is concentrated on:

• Rehabilitation and earthworks contractors
• Environmental monitoring service providers
• Site security and asset management vendors
• Decommissioning and salvage specialists

During peak operations, DeGrussa deployed a fully integrated underground mining circuit relying on complex conveyor systems for ore haulage from depth to surface processing. The remote setting made on-site mechanical workshop capability mission-critical — any conveyor or mobile fleet downtime translated directly into disproportionate production losses given the impossibility of rapid OEM response at 900 km from Perth. Residual infrastructure now supports closure-phase earthmoving and water management operations.

Sandfire has committed to a rigorous proactive rehabilitation programme aligned with Western Australian DMP closure standards. Key ESG workstreams currently active include:

• Tailings Storage Facility (TSF) capping, revegetation, and long-term stability monitoring
• Progressive landform recontouring to pre-disturbance contours
• Groundwater and surface water quality surveillance
• Biodiversity offset and native seed propagation programmes

The TSF management protocol represents the highest-risk ESG liability and drives the majority of current contractor engagement on site.