Highway 11 Realignment Preferred Alternative Option 1D (optimized) Key Advantages (+) / Disadvantages (-) + Comparatively lowest cost to construct. Comparatively lowest construction complexity. + Optimal highway geometry to address design and traffic safety issues. + Lowest effect on watercourses and fish habitat. + Comparatively lowest wildlife habitat disturbance. - Moderate vegetation removal and wetland disturbance. -Higher effects on the Golf Course. 1
Hydro One Substation Relocation Preferred Alternative Key Advantages (+) / Disadvantages (-) Option 1A/B northwestof Old Arena Road + No wetland disturbance. + Lowest effect on wildlife and wildlife habitat. + Lowest cost. - Higher forest removal. -Site will require additional assessment prior to construction for areas of archaeological potential, but potential is low based on work to date. Note - Four alternatives (1, 1A/B, 2 and 2A) were considered in the comparative analysis. 2
Process Water Supply Reference: pumpsandsystems.com Preferred Alternatives Key Advantages (+) / Disadvantages (-) Reclaim water recycled from TMF and site contact water collection system + Closed system will limit effluent discharge and will not result in environmental effects on water features or fish habitat. + Provides the opportunity for the highest process efficiency through water reuse. +Reduced cost for water treatment. Groundwater form Historic Underground Workings + Closed system will limit effluent discharge and will not result in environmental effects on water features or fish habitat. + Provides a good supplemental reclaim water source to support process efficiency. + Reduced cost for water treatment. 3
Borrow Sources Preferred Alternatives Use Existing Quarries or Pits Use Mined Waste Rock Create New Quarries or Pits Key Advantages (+) / Disadvantages (-) + Limited potential for environmental effects since sites are already established. +Will provide government revenue through licensing. - Aggregate availability may be limited at existing sites and may not fulfill the project needs. - Increased use of existing roads. + Limited potential for environmental effects since operations will be localized at the mine site. + Provides a ready supply of usable waste rock. -May not fulfill all project needs. + Provides flexibility to ensure appropriate aggregate sources are available to fulfill the project needs. +Will provide government revenue through licensing. - May result in increased noise at local receptors. - May result in increased effects to vegetation, wetlands and wildlife. - Increased use of existing roads. - Increased cost to establish new borrow sources. -May result in the need to mitigate effects on land and resource uses and traditional uses. 4
Drinking Water Supply Preferred Alternative Key Advantages (+) / Disadvantages (-) Connect to Geraldton Municipal Supply + No expected effects to water features or fish. + No disturbance to existing vegetation, wetlands or wildlife. + Lowest capital and operating costs. + No additional treatment required to address water quality issues since water will be treated municipally. 5
Temporary and Backup Power Sources Preferred Alternatives Key Advantages (+) / Disadvantages (-) 44 kv Tie-in to existing Transmission Line Temporary Diesel or Natural Gas Generation + No GHG or air emission during operation. + Limited potential effect on the natural environment. + Lower capital and operating costs. - Potential reliability issues associated with severe weather events. + Increased reliability from the ability to store fuel on site for continued operation. - Ongoing GHG and air emissions during operation - Minor risk of groundwater effects from spills. - Higher capital and operating costs. 6
Fuel Type for Mining Equipment Preferred Alternatives Key Advantages (+) / Disadvantages (-) Diesel Fuel Supply Combination LNG / Diesel Fuel Supply (long term) + Lower capital costs. - Higher air quality effects. -Higher fuel costs over life of mine. + Reduced air quality and GHG emissions. + Increased cost savings over LOM. -Higher capital cost to establish diesel/lng operations, which may not be viable until production ramps up. - Technology not yet commercially available. 7
Fuel Source for Mining Equipment Preferred Alternatives Key Advantages (+) / Disadvantages (-) Diesel Truck Delivery and Tank Storage (long term) LNG Truck Delivery and Tank Storage (short term) LNG Liquefaction Plant (long term) + Lower capital cost. - Higher operating cost. - Higher GHG and air emissions from trucking. + Lower capital cost. - Higher operating cost. - Highest GHG and air emissions from long distance trucking. + Lower operating cost. + Reduced GHG and air emissions. - Higher capital cost. 8
Open Pit Closure and Decommissioning Preferred Alternative Key Advantages (+) / Disadvantages (-) Open Pit Enhanced Refilling + Will limit the time required to complete closure activities. + Reduced costs over closure period. 9
Preferred TMF Preferred Alternative Key Advantages (+) / Disadvantages (-) TMF-8 Conventional Tailings + Lowest effect on water resources + Comparably low effect on fish habitat + Lowest effect on air quality + Smaller relative surface area for closure + Lower capital, operational and closure costs - Higher effects on wetlands - Less favorable foundation conditions - Larger diversion requirements - Higher visual effect due to embankment heights 10
Goldfield Creek Diversion Preferred Alternative Key Advantages (+) / Disadvantages (-) Option 6 Northeast diversion to SW Arm Tributary + Lowest cost. + Lowest alteration to existing channels. + Lowest effect on existing fish habitat. + Lowest vegetation and wetland disturbance. + Lowest effect on wildlife and wildlife habitat. - Higher risk of flood impacts by diverting all flows through northeast channel. 11