2021 Pre-Feasibility Study

Spring Valley is planned to be a large open pit mine that extracts 267 million tons of ore at a stripping ratio of 3.5:1.0. The planned ROM and crushed ore leach processes is anticipated to recover a combined 3.2 million ounces gold over an 11-year mine life. Salient metrics for the project are given in the table below. Note: the Project economics were evaluated using flat long-term prices drawn from a consensus of North American analysts, including gold at US$1,600/ounce.

Metallurgy

Metallurgical testwork has confirmed the amenability of the ores to heap leaching processing with trade-offs resulting in a final flowsheet that uses conventional heap leach processing with a high-grade crushed process stream and a low-grade run-of-mine (ROM) process stream.

Mining

The mine plan will entail excavation of 1.2 billion tons of material over a period of 13-years including an 18-month pre-strip period. The material will be excavated by large surface mining equipment that will operate at high production rates and achieve economies of scale.

Processing

Crushed and ROM ores from the Spring Valley pit will be processed using conventional heap leaching technology, followed by an adsorption desorption recovery (ADR) circuit and refinery that will produce doré onsite.

Infrastructure

Onsite infrastructure and services required to support the Project include mining and process ancillaries, waste rock storage facilities, pit dewatering and rapid infiltration basins, stormwater collection ditches and basins, general buildings and site storage, power supply and distribution, freshwater distribution, and fuel storage and distribution.

A portion of the Lovelock-Unionville Road, also known as the Spring Valley Road, and a 345kV powerline pass through the site and both will be re-routed before the start of operations. The Spring Valley Road extends to the Buena Vista Valley Road to the east of the site facilities. Prior to operations, the Buena Vista Valley Road will be upgraded.

Spring Valley Project