The mining newspaper for Alaska and Canada's North
The mining newspaper for Alaska and Canada's North
Considers underground mining, leverages AI to guide drilling North of 60 Mining News - February 10, 2023
The 2022 PEA for a mine at Lawyers envisions a centrally located mill facility processing gold-silver ore from open pit mines at the AGB, Cliff Creek, and Dukes Ridge deposits.
Underground resource expansion potential of the Cliff Creek and Dukes Ridge deposits at Lawyers.
Benchmark Metals Inc. Feb. 10 reported that it will focus its 2023 programs at Lawyers on work to advance the gold-silver mine project in Northern British Columbia to feasibility and permitting. This includes artificial intelligence-supported resource modeling to delineate and explore the underground expansion potential of the deposits at Lawyers.
"Benchmark has significant potential to leverage already drilled mineralization below the open pits to add high-grade gold and silver material in an updated engineering and economic study," said Benchmark Metals CEO John Williamson.
A preliminary economic assessment completed in August envisions ore from open-pit mines at three Lawyers deposits – AGB, Cliff Creek, and Dukes Ridge – feeding a centrally located mill that would produce 1.7 million ounces of gold and 26.7 million oz of silver over an initial 12 years of mining.
This PEA is based on 67.38 million metric tons of measured and indicated resources averaging 1.26 grams per metric ton (2.74 million oz) gold and 24.39 g/t (52.9 million oz) silver; plus 4.87 million metric tons of inferred resource averaging 2.39 g/t (378,000 oz) gold and 39.41 g/t (6.2 million oz) silver.
Building upon this PEA, the Benchmark engineering team is carrying out a series of optimization studies that includes the evaluation of the underground mining potential at Lawyers.
"The ongoing underground mining and optimization studies have potential to significantly improve the project economics," said Williamson.
The underground mining assessments are part of a larger optimization study for Lawyers that is evaluating opportunities to optimize the project as a whole – mining, processing, infrastructure, power, equipment, and tailings management.
An initial investigation is being carried out to identify areas to improve project economics based on the incorporation of recently completed geotechnical fieldwork, mineral processing design work, and other optimization studies. This will be followed by a re-evaluation of the mine plan and mining deliverables based on a combined open pit and underground mining scenario.
While Benchmark believes the current resource is robust enough to support feasibility-level studies for a mine at Lawyers, the company is planning additional resource expansion and upgrade drilling around the three deposits included in the PEA.
One of the primary objectives of the 2023 drilling will be to further delineate and expand upon the underground resources.
As a first step to understanding the underground potential, the Benchmark exploration team engaged Maptek, a leading mining technology company, to generate a machine learning AI model to predictively determine grades and further characterize the resource. In addition, geochemical models of lithology and alteration have been generated to complement the grade models and the existing structural and mineralization models.
Benchmark says these new models align closely with the current model and provided further guidance for resource and expansion target areas to be investigated in 2023.
While exploring the resource expansion potential ahead of a feasibility study, Benchmark is continuing baseline environmental studies in preparation for the mine permitting process.
The Benchmark environmental teams are in the final year of a two-year environmental baseline program that will support an environmental assessment application for developing a mine at Lawyers.
"The project is delivering clean environmental results, including non-acid generating mineralization and waste rock," said Williamson.
With the completion of all environmental baseline studies, Benchmark expects to begin the EA process planning and preparation of the initial project description in early 2024.
Depending on the outcome of this year's exploration and engineering programs, the operation advanced into permitting is likely to include the deeper gold-silver potential identified at Lawyers.
"Benchmark has great potential to position itself as a key player in a Tier 1 Canadian jurisdiction during the start of a precious metals bull market," the Benchmark Metals CEO added.
Over his more than 16 years of covering mining and mineral exploration, Shane has become renowned for his ability to report on the sector in a way that is technically sound enough to inform industry insiders while being easy to understand by a wider audience.
Reader Comments(0)