Twin Metals Minnesota Prefeasibility Study

Twin Metals Minnesota (TMM) wanted to pursue a 21^st century underground mining project in the Duluth Complex, one of the largest undeveloped copper, nickel, and platinum group mineral deposits in the world. However, TMM recognized that the mine’s proximity to the Boundary Waters Canoe Area Wilderness and the surrounding private, state, and federally protected land required a team that understands the unique nature of this project and could provide the appropriate solutions.

TMM asked our Mining team to complete a prefeasibility study, and we realized innovative methods were required to reduce the noise and visibility of the potential mining activities. As a result, we proposed combining the primary ventilation and heating system into one integrated facility to significantly cut down on noise levels. Additionally, a computational fluid dynamic analysis was performed to predict the visibility of ventilation plumes throughout various seasons and times of day.

Optimization was key to this project. To maximize efficiency and reduce costs, our team helped TMM with the scheduling and design of a modified long-hole mining method combined with cemented hydraulic fill and waste rock. These solutions are expected to be fully sustainable throughout the 25-year life of the mine.