The AER found that Mildred Lake Extension Project (MLX) did not meet Directive 085: Fluid Tailings Management for Oil Sands Mining Projects requirements. Syncrude has until 31 January 2023 to submit an "updated Tailings Management Plan" that aligns with Tailings Management Framework for the Mineable Oil Sands (TMF). The "TMF under the Lower Athabasca Regional Plan (LARP) provides direction to the AER and industry on the management of fluid tailings during and after mine operation. AER Directive 085, under the Oil Sands Conservation Act (OSCA), "sets out requirements for managing fluid tailings for oil sands mining projects."The project includes two new open-pit mining operations that would operate with "conventional shovel and truck mining technology". The Mildred Lake Extension (MLX east), located west of the Athabasca River, and Mildred Lake Extension (MLX west), west of the Mackay River are about 35 kilometres (km) north of Fort McMurray the Regional Municipality of Wood Buffalo (RMWB) and about 10 km north of the hamlet of Fort McKay. Most of Fort McKay is situated on Fort McKay First Nation (FMFN) lands. These two new mines would extend Syncrude's mining activity using old technologies by about 14 years (AER 2019:2).
