Tierra Group conducted a siting analysis for a new WRSF to support the mine’s future production increase as part of the Preliminary Feasibility Study (PFS).

In addition to supporting the PFS, Tierra Group assisted in preparing and submitting several engineering design changes (EDC) to increase the existing WRSF’s operating life. The project involved a waste rock dump expansion with civil design and stability modeling to ensure compliance with regulatory dam safety criteria. Tierra Group completed unsaturated modeling to support the WRSF closure cover design for the Waste Rock Repository (WRR), comparing alternative cover configurations to minimize long-term infiltration through reactive waste rock, selected a preferred cover geometry, and completed draindown analyses for both facilities to support site closure and bonding requirements.

In addition, Tierra Group conducted waste rock field sampling and laboratory tests to confirm hydraulic parameters for modeling. The team developed water balance models to monitor meteoric and seepage flows into the WRSF's collection pond. Finally, Tierra Group addressed comments from the Bureau of Mining Regulation and Reclamation (BMRR) related to WRSF seepage site tracking, modeling parameters, and closure designs.