Mine waste geotechnique

Kemess Tailings Dam in central BC, Canada

Kemess Tailings Dam in central BC, Canada

You would probably think that mining is mostly about mining the ore. Well it is. But, it turns out that if you look at how many people are doing what around a mine (particularly an open pit mine), you  might be surprised to see that most people are more involved with mine waste than the orebody. And the same holds for mine geotechnical engineers — probably 90% of us are involved in mine waste.

The reason? Partly that most mines have a high ratio of waste to ore, often ten times. And the waste rock, stored in large dumps, often generates contaminated water (often acid rock drainage). And the tailings (the ground up ore with the economic minerals extracted) is typically slurried out to the far reaches of the mine site where it also needs quite a lot of geotechnical design and geochemical help. And the mining sprawl (the ratio of the area of mining disturbance to the pit boundaries) is often 2 to 4, so there is a lot of area to monitoring, regrade, cover, and revegetate — also keeping a lot of people busy.

Topics in mine waste geotechnique broadly include:

  • Dump site investigation, design, construction, regarding, reclamation, water management and water treatment
  • Tailings dam site investigation, design, construction, regarding, reclamation, water management and water treatment
  • Tailings management (planning, containment, deposition, monitoring, covering, reclamation, soft tailings)
  • Site water management (water management, design, construction, operation, water treatment, closure)
  • Roads, access, and infrastructure
  • Stakeholder engagement and permitting
  • Landform design and closure planning

 

Here are some photos from various mine’s that I’ve visited on conference tours over the past 25 years that illustrate the breadth of mine waste geotechnique…

 

Reclaimed tailings at Pinchi Mercury Mine near Fort St James, BC, Canada.

Reclaimed tailings at Pinchi Mercury Mine near Fort St James, BC, Canada.

 

Weathered waste rock dumps at Molycorp Mine near Questa, New Mexico, USA

Weathered waste rock dumps at Molycorp Mine near Questa, New Mexico, USA

 

Reclaimed coal waste rock dump at McKinley Coal Mine near Farmington, New Mexico, USA in 1996

Reclaimed coal waste rock dump at McKinley Coal Mine near Farmington, New Mexico, USA in 1996

 

Reclaimed waste rock and mine shafts at Elliot Lake, Ontario, Canada in 1996

Reclaimed waste rock and mine shafts at Elliot Lake, Ontario, Canada in 1996

 

Weathered waste rock at a mine in central British Columbia, Canada

Weathered waste rock at a mine in central British Columbia, Canada

 

Waste rock dump at the Greens Creek Mine near Juneau Alaska USA

Waste rock dump at the Greens Creek Mine near Juneau Alaska USA

 

The reclaimed tailings pond at Brenda Mine near Summerland, BC, Canada

The reclaimed tailings pond at Brenda Mine near Summerland, BC, Canada

 

Acid rock drainage from waste rock at a lead zinc mine

Acid rock drainage from waste rock at a lead zinc mine

 

Pinchi Mercury Mine -- highwall reclamation. near Fort St James, BC, Canada.

Pinchi Mercury Mine — highwall reclamation. near Fort St James, BC, Canada.