Castle Mountain Phase 2

Phase 2 Highlights

The information below is based on economic, engineering and other information available at the time of publishing the March 2021 feasibility study using the base case gold price of $1,500/oz and an upside scenario of $1,800/oz gold, which was the prevailing spot price at the time. Equinox Gold will update this information as part of engineering, optimization studies and economic reviews before making a construction decision.

• After-tax NPV_5% of $640 million at $1,500/oz gold ($1.1 billion at $1,800/oz gold)
• After-tax IRR of 18% at $1,500/oz gold (25% at $1,800/oz gold)
• $1.3 billion after-tax cumulative net cash flow at $1,500/oz gold ($2.0 billion at $1,800/oz gold)
  • $114.1 million average annual after-tax net cash flow at $1,500/oz gold ($161.8 million at $1,800/oz gold)
• <$950/oz average AISC
• 218,000 oz average annual gold production (Phase 2 life of mine)
• 3.2 million oz total gold production at an overall average recovery of 82%
  • 1.1 million oz produced from the mill at an average recovery of 94%
  • 2.1 million oz produced from the heap leach at an average recovery of 67% (74% after final rinsing)
• $389 million initial capital costs, excluding $121 million leased mining fleet.
  • $510 million if the fleet is purchased up front; NPV_5% and IRR assume fleet is purchased up front.
• $147 million sustaining capital costs over the Phase 2 mine life
• 14-year Phase 2 mine life with expansion potential from exploration, plus two to three years of residual leaching and final rinsing

Using economic data available in March 2021, initial capital costs were estimated at $389 million, excluding the mining fleet which is expected to be leased. Sustaining capital for Phase 2 was estimated at $147 million.

Phase 2 will operate within the current approved Mine Permit boundary and existing Phase 1 site infrastructure will be incorporated into the expansion, including administration buildings, haul roads, solution handling pumps and storage tanks, a carbon-in-column (CIC) cyanide receiving and storage area, a heap leach pad and event pond, a diesel power generation plant and an assay and metallurgical laboratory.

The Phase 2 heap leach facility will consist of an enlarged heap leach pad, an additional event pond, additional larger solution handling pumps and an additional CIC plant. The new CIL plant will consist of a two-stage crushing facility, conveyors, ball mill circuit, gravity concentration, leach and CIL tanks, thickeners, tailings filters and a reagent handling area. Loaded carbon will be processed in a desorption, electrowinning and refinery plant. Additional infrastructure for Phase 2 will include water supply wells, pumps and distribution systems, installation of an electrical transmission line along a previous corridor, an electrical substation, a filtered tailings storage facility, an extension of two waste rock dumps, a truck shop, and various site improvements and upgrades to meet the expanded project needs.

Leached slurry from the CIL circuit will report to a cyanide recovery thickener to recycle as much water and cyanide as possible back to the process. Flocculant will be added to aid in settling solids to produce a thickened product that will be treated in a cyanide destruction process. The final tailings will be pressure filtered and the filtered tailings will be hauled and stacked on the historical heap leach facility and abutted to the expanded heap leach facility, which allows the Company to minimize new land disturbances.