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Mayor: Let the MNR know Atikokan assets need to be part of Steep Rock rehab plan

Mayor: Let the MNR know Atikokan assets need to be part of Steep Rock rehab plan

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Council wants Atikokanites to press the province to include the future of Highway 622 and the Atikokan ski hill in its plan for the rehabilitation of the Steep Rock Mine.

Neither asset was addressed by the MNRF in its Steep Rock Mine: Conceptual Rehabilitation Approaches, a document filed on the Environmental Registry prior to the March 9 consultation here.

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“There doesn’t seem to be any movement at all to save the ski hill or Highway 622; it’s not discussed in the proposals at all,” Mayor Brown told Council on Monday. “It needs more discussion, anyway… to try to save those two assets for Atikokan.”

He urged councillors and residents to file a comment about these assets by the deadline (April 22). Comments can be made at the Registry site (search for Steep Rock rehab at www.ebr.gov.on.ca), or directly to Jeff.Bonnema@ontario.ca or Sheldon.Haw@ontario.ca.

“This issue is so important to Atikokan that all of us should be taking an interest, especially the younger people,” said the mayor.

Key issues

The document (also available here: final-steep-rock-mine-fact-sheet.pdf) covers the Ministry’s efforts to understand what is happening at the old mine site, and cites six possible approaches for site remediation developed by consulting mining engineers.

Those approaches take into account nine key findings from recent studies of the site:

  • Metal contamination in soil has been found around the two plants near Caland and Hogarth open pits.
  • Hydrocarbon (mostly fuel) contamination, while extensive in places, is generally limited to six locations.
  • Natural recovery of the pit lakes will result in the continued rise of water levels until the maximum fluid level elevation of 394 metres above sea level is reached in approximately 2070.
  • Water from the merged Caland-Hogarth pit lake is expected to discharge to the West Arm, in the vicinity of the Narrows Dam.
  • Sulphate levels in the pit lakes water is of particular concern, with concentrations ranging between 300 and 1,200 milligrams per litre. All other parameters or contaminants of concern are expected to be close to meeting the provincial water quality objectives.
  • Water quality of the pit lakes is estimated to improve with time without intervention. Pit water inflows are expected to improve in quality as the rock waste piles and pit walls are flooded by the rising pit lake levels (i.e., decreased exposure to oxygen decreases acid rock drainage).
  • The continued development of stratification – layering of clean water – in the pit lakes could further improve the water quality in their upper layer of water.
  • Depending on existing regulations, the water quality of the naturally recovered pit lakes may be suitable for direct discharge into the environment without treatment.
  • Removal (or isolation) of mine wastes would reduce sulphate concentrations in the pit lakes; however, the level of effort required to achieve this reduction is significant.

Proposed approaches

The six proposals are approaches only; they are far from detailed plans. The document acknowledges this, noting they reflect “that the goals for site rehabilitation may change over time and that more stringent requirements may be required in the future. Further, the recommended approach needs to be flexible to allow for changes that may be required to address future conditions and/or environmental guidelines.”

All of the approaches essentially see Steep Rock Lake reforming in the M shape it had before the mining project began.

Without some sort of intervention, the overflow from the pits will spill over the Narrows Dam and into the West Arm of Steep Rock Lake. That is an issue. When the diversion began, heavy sediment from Steep Rock dredging was flushed into the Seine River and on to Rainy Lake, causing great havoc to water supplies and the fisheries there. So Steep Rock officials isolated the West Arm, where the sediment-rich dredging product could settle.

Will that sediment be stirred up if the overflow from the pits passes through the West Arm? That needs more study. Approaches five and six explore different scenarios using this route.

The other approaches propose three possible alternative routes for the pit overflow:

  • through a new channel linking the Southeast Arm to Strawhat Creek (and then on to the Atikokan River just east of town).
  • from the Middle Arm to Highland Lake (channels would have to be dug on either side of the lake, and the lake lowered about four metres), to a creek and on to the river, meeting it just east of its mouth on Apungsisagen Lake.
  • from the Middle Arm via a pipeline around Highland Lake to Apungsisagen.

The proposals include several options in which the acid-producing mine tailings piles are removed or capped.

Input from the public will be considered in conjunction with the engineering analysis to choose a recommended approach, which should be ready later this year.

“Rehabilitation of the site will unfold over a long period of time. Rehabilitation planning and implementation will require a flexible approach to be responsive to the complexity of the site and evolving conditions (e.g., advances in technology, changing climate, response of the environment to cleanup actions).”

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