The Syncrude Mildred Lake Extension (MLX) project is located approximately 40 kilometres north of Fort McMurray within Township 093 and 094, Range 12, W4M in the Rural Municipality of Wood Buffalo, Alberta.
The MLX-W Clean Water Return (CWR) project is one of a series of projects to support the development of the MLX-W mine to first ore in 2024. The MLX-W mine is essential; it provides continuity of oil sand feed supply to the plant. It overlaps with remaining ore from the North Mine resource and the future MLX East or Aurora South.
The MLX-W CWR project is designed to intercept and re-direct clean runoff from upstream catchments around the mine development and discharge to MacKay River.
The following challenges were addressed during the design of this outfall:
- Proximity to Creek E which is unstable requiring a minimum 60 m setback distance.
- Proximity to MacKay River escarpment, that required a minimum setback distance of 80 m for stability purposes.
- The elevation drop of 54.4 m in a distance of 1,574 m (3%); this could not be implemented due to large volume of earthworks. As a result three chutes with slopes of 12.5%, 7.1%, and 7.9% were implemented to reduce earthworks.
- Gabion chutes and gabion plunge pools were designed for energy dissipation.
- Three wildlife corridors were designed for wildlife crossings as the requirement based on EIA.
- Preliminary site survey
- Channel and road route selection
- Hydrology and hydraulic analysis
- Clean water diversion channel designs (102A, 102B and 102C)
- Geometric service and access road design
- Culverts and pedestrian bridge structure design
- Temporary outfalls and permanent MacKay River outfall design
- Utility coordination
40 kilometres north of Fort McMurray within Township 093 and 094, Range 12, W4M in the Rural Municipality of Wood Buffalo, Alberta