Northern Ontario's Steep Rock Mine water to overflow by 2070
Ontario's Ministry of Natural Resources and Forestry looks for treatment options for mine
The problem is decades away, but the Ministry of Natural Resources and Forestry wants to figure out the best way to control water that will eventually overflow the former Steep Rock, Caland and Hogarth open pit iron ore mines, in northwestern Ontario.
The MNRF projects the two pits will overflow in 2070.
Graeme Swanwick,the Executive Lead on the Steep Rock Mine Rehabilitation Project, said the process will take decades.
"So we expect rehabilitation of the Steep Rock site is going to unfold over a long period of time."
"The conceptual approaches that have been put forward will serve to improve water quality over time, to a point where it can be released into the adjacent waterbodies, around 2070. So, good water quality is the end goal."
Swanwick said the MNRF is looking into six options.
- Natural Recovery of the pit lakes with gravity flow to the Atikokan River via Strawhat Creek
- Enhanced natural recovery with gravity flow to the Atikokan River via Highland Lake
- Enhanced natural recovery with pumping water from Hogarth Pit to Lower Steep Rock Lake
- Consolidation and capping of mine waste above the final flood elevation with water treatment and pumping to Lower Steep Rock Lake
- Complete removal of all mine waste with enhanced natural recovery of the pit lakes with gravity flow to the West Arm, via Narrows Dam Area
- Enhanced natural recovery with gravity flow to the West Arm via Narrows Dam Area
Swanwick said the other major issue of releasing the water from open pits into the environment, is the impact on water levels on existing infrastructure near the former mines.
"About a one kilometre section of Highway 622 will be flooded, as those pits overflow. So, additional study will be required to determine the best, the most cost effective way of rebuilding or relocating that highway."
Swanwick said the public can comment on the plan until April 22. A link to the actual report can be found here.
The Steep Rock and Caland Iron Mines shut down in 1979 and 1980.
- A previous version of this story did not include information about the small Steep Rock Iron Mine. It also noted the deadline for public comment was the end of April, while the actual deadline is April 22.Apr 20, 2016 4:26 PM ET