Tailings study lifts Monarch Gold's Wasamac

Quebec-based Monarch Gold has welcomed a geochemical assessment of future tailings at its planned Wasamac mine that found these will not be acid-generating and therefore less harmful to the environment.

Environmental consultancy Ecometrix, headquartered in Ontario, conducted a geochemical assessment using ore samples to predict storage and weathering implications. The results showed that these were non-potentially acid generating, and actually contain excess capacity to neutralize acid from external sources.

"This study is of great interest to us, as it indicates that the Wasamac tailings will be significantly less harmful to the environment than if they were acid-generating," said Jean-Marc Lacoste, president and chief executive of Monarch. "In addition, the potential to neutralize acid on existing tailings facilities from Wasamac tailings suggests that Wasamac could be an obvious economic choice for several mills."

With proven and probable mineral reserves of 21.46Mt at an average grade of 2.56g/t of gold, the Wasamac project targets 6,000t per day, with an expected mine life of 11 years. The company filed a project notice with Quebec's Ministry of the Environment and the Fight Against Climate Change last November, the first step in the mining permit application process, which generally takes 18 to 24 months.

Lacoste added that the initial feasibility study for the mine released in 2018 allocated C$234 million (US$167 million) for the construction of a mill and tailings facility. However, a new option is transporting the ore to a new site for custom milling as this could significantly reduce this capex figure.

Monarch announced on May 14 it had agreed with Glencore to develop a work plan that would see ore from the Wasamac gold property shipped to the Glencore's Kidd concentrator in Ontario by the end of 2023.

This article was written by Craig Guthrie and originally appeared in UK-based Mining Magazine www.miningmagazine.com