ENV 100: Mining Impacts and Restoration Study Notes

Introduction

  • Welcome to the last lecture of Module 5 (ENV 100).

    • Reminder about the coffee chat/social gathering happening immediately after the lecture.

Overview of Lecture Topics

  • Focus on the impacts of mining on air, land, water, and human health.

  • Tying together concepts from previous lectures.

  • Areas of discussion include:

    • Environmental impacts of different mining stages.

    • Challenges of decommissioning and restoring mines.

    • Social impacts, including conflict minerals and artisanal small-scale mining.

Environmental Impacts of Mining

  • Variables Affecting Impacts:

    • Type of deposit being mined (different minerals have different environmental footprints).

    • Geological and ecological setting impacts (isolated vs. industrial areas).

    • Mining procedures and management practices.

    • Compliance with laws and policies that vary by country.

Mining Waste

  • Mining operations are extremely wasteful:

    • Waste Generation:

    • For iron: 1 ton mined = 3 tons waste.

    • For base metals (copper, zinc, nickel): 20 - 200 tons waste generated per ton mined.

    • For gold and platinum: 1 ton mined can produce up to 1,000,000 tons waste.

  • In Canada, mining produces over 30 times the waste of all citizens and industries combined annually.

Air Quality Issues

  • Dust from blasting and surface mining can severely impact air quality.

  • Tailings piles are prone to combustion, releasing toxic substances.

  • Smelting and refining processes generate particulate matter, contributing to:

    • Smog.

    • Stratospheric ozone depletion.

  • Toxic gases can also be emitted, causing further air quality degradation.

Water Pollution

  • Toxic Effluents:

    • Bright orange tailings indicate presence of toxic metals (e.g., mercury, lead, cadmium, chromium, arsenic).

    • Toxic tailings can bioaccumulate in the food chain (impacting humans as apex predators).

  • Acid Mine Drainage:

    • Formed when sulfide minerals react with air and water, producing sulfuric acid.

    • Can occur from both active and abandoned mines, leading to the runoff of toxic heavy metals.

Transboundary Environmental Issues

  • Example of Alaskan rivers affected by mining in British Columbia:

    • Pollution from Canadian mines impacting downstream ecosystems and communities.

    • Indigenous and First Nations communities facing threats to livelihoods.

Tailings Storage Facilities

  • Approximately 29,000 to 35,000 active and inactive tailings storage sites globally.

  • Contain over 220 billion tons of tailings; increasing catastrophic spills associated with failing facilities.

Human Health Impacts of Mining

  • Mining operations pose significant health risks to:

    • Workers directly involved.

    • Local communities living near mining sites.

  • Health Risks Include:

    • Exposure to toxic pollutants.

    • Radiation and asbestos risks.

    • Black lung disease (specifically from coal mining).

    • Risks associated with geological instability (potential explosions and collapses).

Stages of Mining and Associated Impacts

  • Four Stages:

    1. Exploration: Minimal impacts; some contamination from drilling and habitat disturbance.

    2. Mining and Milling:

    • Significant impacts from dust, noise, heavy metals exposure.

    • Increased erosion due to surface vegetation removal.

    1. Smelting and Refining:

    • Major air pollution from burning processes, generating airborne contaminants and toxicity.

    1. Postoperational:

    • Issues with contamination after closure depend on management effectiveness.

    • Risks from abandoned equipment and sites, long-term ecological impact.

Restoration and Reclamation Challenges

  • Decommissioning: Process of shutting down mining operations.

  • Restoration: Attempts to return sites to pre-mining conditions, often very difficult.

  • Reclamation: Cleaning sites, filling in mine shafts, planting vegetation, addressing contamination.

  • Ethical considerations regarding reusing decommissioned sites (e.g., Love Canal incident).

Regulations and Ethical Impacts

  • Comparison between lax regulations in developing nations vs. Canadian standards:

    • In Canada, companies must post bonds for reclamation.

  • Discussion on whether Canadian companies should apply Canadian standards abroad.

    • Global standards could protect ecosystems and human rights during mining operations.

Socioeconomic Impacts of Mining

  • Closing mines can lead to job losses and economic downturns in communities.

  • Indigenous communities often disproportionately affected by mining operations.

Conflict Minerals: A Case Study

  • Conflict Minerals: Resources extracted under conditions of conflict (e.g., blood diamonds).

    • Accompanied by human rights violations (e.g., torture, forced labor).

    • Example: The Kimberley Process established in 2003 to regulate diamond trade (over 80 countries participate).

  • Case of Rio Tinto's mining of a historically significant Indigenous site.

Artisanal Small-Scale Mining

  • Informal mining practices in developing areas can significantly impact local economies.

    • High association with child labor and hazardous working conditions due to lack of regulations.

  • Increased demand for cobalt linked to the rise of electric vehicles.

Conclusion of Module 5

  • Mining presents extensive waste generation and significant negative impacts on environmental quality and human health.

  • The need for stringent regulations and responsible practices in the mining industry is paramount for mitigating ongoing social and environmental impacts.

  • Reminder: Quiz on Monday and upcoming Module 6 begins next.