The increasing demand for critical metals, such as nickel (Ni) and cobalt (Co) in the production of batteries needed for electric vehicles (EV), has warranted the need to explore alternative technologies capable of valorizing tailings and waste materials as potential additions to the critical metals supply chain. Pyrrhotite tailings often entrain Ni and Co in mineral matrices amendable to bioleaching. To be economic and sustainable, the process needs to include the recovery of Ni and Co but also the recovery of the major iron (Fe) and sulfur components, work to reduce any waste by-products, as well as support repurposing. Conventional bioleaching of pyrrhotite-rich tailings at pH ≤ 2 requires great amounts of sulfuric acid, and the removal of Fe from the produced metal-rich liquor needs significant amounts of limestone or lime, leading to the generation of large volumes of sludge containing gypsum and ferric oxyhydroxides (which presents solid handling challenges), with the risk of co-precipitation of a portion of the target metals prior to recovery. In collaboration with CanmetMINING, this study investigates the piloting of a bioleaching approach proposed to treat the Sudbury basin pyrrhotite tailings stockpiles. The initial efforts to create a larger-scale piloting circuit allow optimization of operating parameters, which could help resolve the challenges associated with the implementation of a continuous pyrrhotite bioleaching process and make the process viable for industrial applications.