Environmental Gains and Cost Risks Loom as St Barbara Plans 15-Mile Expansion
St Barbara reveals plans to expand its 15-Mile processing plant capacity from 2.1 Mtpa to 3.0 Mtpa, integrating Cochrane Hill ore to target annual gold production exceeding 100,000 ounces.
- Potential expansion of 15-Mile mill throughput from 2.1 Mtpa to 3.0 Mtpa
- Integration of Cochrane Hill ore via quarry-style trucking to 15-Mile plant
- Low capital expenditure expected for plant modifications
- Environmental impact minimized with no crushing or tailings at Cochrane Hill site
- Updated integrated Pre-Feasibility Study targeted for Q3 FY26
Strategic Expansion of Processing Capacity
St Barbara Limited (ASX: SBM) has announced a promising development in its Atlantic projects, revealing the potential to increase the processing capacity of its 15-Mile gold mill from 2.1 million tonnes per annum (Mtpa) to 3.0 Mtpa. This expansion is driven by the integration of ore from the Cochrane Hill project, located approximately 70 kilometres from the 15-Mile plant in Nova Scotia, Canada.
The company’s evaluation work, building on the October 2024 Pre-Feasibility Study (PFS), suggests that the expanded throughput could support annual gold production exceeding 100,000 ounces, a significant milestone that would enhance St Barbara’s production profile in the region.
Innovative Quarry-Style Ore Transport and Processing
The preferred approach involves trucking Cochrane Hill ore to the 15-Mile processing facility using a quarry-style configuration. This method eliminates the need for on-site crushing, processing, tailings storage, or water withdrawals at Cochrane Hill, substantially reducing environmental disturbance and infrastructure requirements.
Recent metallurgical testing confirms that Cochrane Hill’s free-milling ore is compatible with the 15-Mile and Beaver Dam ores, allowing for efficient ore blending at a consistent grind size. This compatibility is expected to lower energy consumption and operating costs, further improving project economics.
Cost-Effective Plant Modifications and Environmental Benefits
St Barbara indicates that the expansion to 3.0 Mtpa can be achieved with relatively low capital expenditure by modifying the existing Touquoy plant, which is planned to be relocated to the 15-Mile site. This approach leverages existing assets to optimize capital efficiency.
In addition, the quarry-style design at Cochrane Hill supports a minimal environmental footprint. By avoiding major infrastructure such as crushing facilities and tailings dams, the project reduces potential ecological impacts and simplifies reclamation efforts post-mining.
Ongoing Evaluation and Future Outlook
St Barbara is continuing detailed evaluation work through the third and fourth quarters of fiscal year 2025, aiming to deliver an updated integrated PFS for the 15-Mile, Beaver Dam, and Cochrane Hill projects by Q3 FY26. This study will refine the mine-to-mill optimization and confirm the economic and environmental benefits of the proposed expansion.
Managing Director and CEO Andrew Strelein expressed optimism about the redesign, highlighting the balance between enhanced economic value and minimized environmental impact. The company’s strategic focus on sustainable development aligns with broader industry trends and investor expectations.
Bottom Line?
St Barbara’s 15-Mile expansion could redefine its Atlantic gold production trajectory, but execution risks remain ahead of the updated PFS.
Questions in the middle?
- What are the detailed capital and operating cost estimates for the 3.0 Mtpa expansion?
- How will ore trucking logistics and costs impact overall project economics?
- What are the potential regulatory or environmental hurdles in finalizing the quarry-style design?
