Benchmark PEA projects $493M capex for 12-year open pit mine at Lawyers

Benchmark Metals (TSXV: BNCH; OTC: BNCHF) has completed a preliminary economic assessment (PEA) on its flagship Lawyers gold-silver project that presents a robust open pit mining scenario with attractive economics at base case gold and silver prices.

The project’s after-tax net present value (at 5% discount) is estimated at $577 million, with an internal rate of return of 23.5% and 2.7-year payback period. The initial capital cost is projected at $493 million (including $72.8 million in contingency). Life-of-mine capital for the project, located within the Golden Horseshoe area of north-central B.C., totals $632 million.

Benchmark Metals CEO John Williamson examines drill core at the Lawyers project. Credit: Benchmark Metals

Over its 12-year mine life, the Lawyers mine is expected to produce 141,000 oz. of gold and 2.2 million oz. of silver annually, from processing of 46.3 million tonnes of ore at diluted grades of 1.23 grams gold per tonne and 23.73 grams silver.

“The PEA clearly demonstrates the low cost and robust return of the Lawyer’s gold-silver project even when stress tested with considerable contingency in the base case,” said John Williamson, Benchmark’s CEO, in a release. “We continue on a straightforward pathway to advancement.” 

The PEA considers a conventional truck-and-shovel open pit mining operation covering the Cliff Creek, Dukes Ridge and AGB pits, feeding a 10,600-tonne-per-day conventional processing plant. Operations would begin at the AGB deposit and transition in year two over to the Cliff’s Creek and Duke’s Ridge deposits for the remainder of the mine life.

“The PEA confirmed the current project development timelines, with industry standard open pit mining methods, processing flowsheet, design criteria, and compact footprint,” said Ian Harris, VP engineering, adding that multiple target high-grade resource areas have been identified close to but outside of the pit limits.

“There is a significant opportunity to upgrade the already robust project through adding underground mining to production scheduling,” he added. “These evaluations that represent a considerable upside opportunity will be incorporated into detailed mine planning of the feasibility study.”

Environmental baseline studies to support its environmental assessment application are well underway. The two-year aquatics and terrestrial baseline programs, as well as the geochemical and hydrogeological studies, have all commenced. The company expects completion of all environmental baseline studies by the third quarter of 2023.