📋 Case Study
Mount Polley Tailings Storage Facility Closure & Water Cover Implementation
Legacy tailings with sulfidic mineralogy requiring >100-year ARD suppression
🏗️ Project Overview
Former copper-gold mine in British Columbia, Canada
🎯 Challenge
Legacy tailings with sulfidic mineralogy requiring >100-year ARD suppression
🔧 Design Approach
Submerged water cover (≥3 m depth) combined with sediment capping and shoreline stabilization using bio-engineered toe structures
📐 Design Diagram
AI-generated project design illustration
📐 Key Calculations
Water Cover Hydraulic Retention Time
Volume / Inflow Rate
Result: ≥10 years
Ensures sufficient residence time for oxygen depletion
Sediment Accumulation Rate
Measured Deposition / Time
Result: 1.8 cm/yr
Informs resurvey frequency and cover replenishment planning
📊 Results
Complete ARD suppression confirmed over 7-year monitoring; <0.1 mg/L sulfate discharge; native aquatic community re-established💡 Lessons Learned
- •Water cover depth must exceed maximum wind-driven wave base
- •Sediment geochemistry monitoring is critical pre- and post-submergence
- •Shoreline erosion control requires integrated geomorphic + biological design
✅ Key Takeaways
- 1Water cover depth must exceed maximum wind-driven wave base
- 2Sediment geochemistry monitoring is critical pre- and post-submergence
- 3Shoreline erosion control requires integrated geomorphic + biological design