Environmental Impacts of Potash Mining

Saskatchewan Eco Network

POTASH: Several potash companies operate in the province including Agrium, IMC and the Potash Corporation of Saskatchewan. 

The largest is the Potash Corporation. Since its privatization in 1989, it has become the world's largest fertilizer enterprise, with net sales exceeding $US 2.3 billion in 1997.

The corporation operates six mines in Saskatchewan plus one in New Brunswick and another in Utah. The majority of production (>90%) is exported.

• List of Saskatchewan's Operating Mines

• Industry view of environmental issues

The publication Environmental Aspects of Phosphate and Potash Mining, produced by the United Nations Environment Program (UNEP) and the International Fertilizer Association (IFA), is one of the first books to emphasize environmental aspects of the mining of phosphate rock and potash for fertilizer. It reviews current environmental practice in the industry and discusses various environmental management tools. It is aimed mainly at the fertilizer industries. The book is available on line (PDF). 

According to the UNEP / IFA document, the activities of the potash mining industry potentially result in a wide variety of adverse environmental effects. Typically, these effects are quite localized, and in most cases confined to the mine site. At a specific site, the type and extent of environmental effects may depend on factors such as the characteristics of the ore and overburden, the surface land profile (wetlands, plains, hills); the local climate; and the surrounding ecosystem.

Of greater importance may be the mining methods and equipment used, the beneficiation (refining) and concentration processes; the waste disposal methods; the scale of the operation; and proximity to existing population centers and infrastructure.

Major potential environmental effects that may occur during potash mining activities:

• Mine Development Phase 

  Exploration, assessment, planning and construction:

  • Land surface disturbance
  • Air emissions
  • Water contamination
  • Noise and vibration

• Extraction Phase

  Overburden removal or ore body access and ore extraction:

  • Land surface disturbance
  • Water contamination
  • Water table lowering
  • Air emissions
  • Topsoil degradation
  • Vegetation and wildlife disruption
  • Noise and vibration

• Ore Handling and Transport Phase

  Storage and reclamation:

  • Air emissions
  • Water contamination
  • Noise

• Benification (Refining) Phase

  Size reduction (crushing, grinding, screens, cyclones); separation, concentration and contaminant removal; drying, compaction, granulation, etc.:

  • Waste generation
  • Water consumption
  • Water contamination
  • Air emissions, including CO2
  • Noise and vibration

• Waste Disposal Phase

  Wastes to surface, storage impoundments and piles, underground backfilling, deep well injection, or release to the environment:

  • Land surface disturbance
  • Water contamination
  • Air emissions
  • Aesthetic changes
  • Waste

• Closure Phase (Decommissioning)

  Removal of equipment and plant, shaft sealing, stabilization, and monitoring:

  • Long term stability issues
  • Safety issues
  • Future land use issues
  • Air emissions
  • Hazardous waste disposal