10.1 Existing Environment

10.1.1 Environmental Assessment Boundaries
10.1.2 Administrative Boundaries
10.1.3 Technical Boundaries
10.1.4 Data Collection and Methods
10.1.5 Existing Conditions

10.1.5.1 Regional Characterization and Water Flows
10.1.5.2 Summary of Water Quality
10.1.5.3 Voisey's Bay Drainage
10.1.5.4 Kangeklualuk Bay Drainage
10.1.5.5 Kangeklukuluk Bay Drainage
10.1.5.6 Throat Bay Drainage
10.1.5.7 Anaktalak Bay Drainage

10.1.6 Likely Future Conditions

10.2 Environmental Effects Assessment 

10.2.1 Contaminant Modelling

10.2.1.1 Source Characterization
10.2.1.2 Receiving Environment
10.2.1.3 Model Predictions
10.2.1.4 Model Uncertainty
10.2.1.5 Other Water Quality Considerations

10.2.2 Voisey's Bay Drainage

10.2.2.1 Reid Brook Watershed
10.2.2.2 Southern Watersheds

10.2.3 Kangeklualuk Bay Drainage

10.2.3.1 North Tailings Basin Watershed

10.2.4 Throat Bay Drainage

10.2.4.1 Throat Bay Watershed

10.2.5 Kangeklukuluk Bay Drainage 

10.2.5.1 Option 5 Watershed
10.2.5.2 Pond 67 Watershed

10.2.6 Anaktalak Bay Drainage 

10.2.6.1 Little Reid Brook Watershed and Port Site Drainage

10.2.7 Summary
10.2.8 Accidental Events 

10.2.8.1 Hazardous Materials Spill
10.2.8.2 Fire
10.2.8.3 Pipeline Rupture
10.2.8.4 Storm Events
10.2.8.5 Dam Failure
10.2.8.6 Road Washout and Flooding

10.2.9 Cumulative Environmental Effects
10.2.10 Environmental Design, Mitigation and Optimization 

10.2.10.1 Design-related Mitigation Strategies
10.2.10.2 Potential Mitigation Measures

10.3 Residual Environmental Effects

10.3.1 Construction
10.3.2 Operation
10.3.3 Decommissioning
10.3.4 Post-Decommissioning
10.3.5 Accidental Events
10.3.6 Follow-up Program

10.4 References

Appendix 10A IMPACT^TM Model
Appendix 10B Water Quality Parameters
Appendix 10C Existing Knowledge - Acid Generation of Tailings and Mine Rock
Appendix 10D Environmental Effects Assessment Synthesis: Water

Figure 10.1 Water Assessment Area Watersheds
Figure 10.2 Freshwater Pond and Stream Water Quality Sample Locations
Figure 10.3 Areas of Subsurface Investigations to Determine Groundwater Quality
Figure 10.4 Location of Permanent and Temporary Gauging Stations
Figure 10.5 Daily Flow Distribution - Ugjoktok River
Figure 10.6 Specific Runoff Permanent Stations, 1995 - Reid Brook Watershed
Figure 10.7 Specific Runoff Permanent Stations, 1996 - Reid Brook
Figure 10.8 Specific Runoff Temporary and Permanent Stations, 1996 - Camp Brook Watershed
Figure 10.9 Specific Runoff Permanent Stations, 1996 North Tailings Basin
Figure 10.10 Surficial Geology
Figure 10.11 Bedrock Geology
Figure 10.12 Tailings/Mine Rock Deposition Plan at Headwater Pond
Figure 10.13 North Tailings Basin Layout
Figure 10.14 Spatial Extent of Residual Environmental Effects - Water Chemistry - Open Pit Operations
Figure 10.15 Spatial Extent of Residual Environmental Effects - Water Chemistry - End of Operations
Figure 10.16 Spatial Extent of Residual Environmental Effects - Water Chemistry - Post-decommissioning

Table 10.1 Federal and Provincial Water Quality Regulations and Guidelines
Table 10.2 Average Measured and Estimated Flows 1996
Table 10.3 Voisey's Bay Selected Study Ponds - Drainage Basin Information
Table 10.4 Unadjusted Median Values of Water Quality Parameters
Table 10.5 Adjusted Ranges of Values for Water Quality Parameters
Table 10.6 Summary of Precipitation Chemistry (1990-1996)
Table 10.7 Potential Environmental Effects within the Reid Brook Watershed
Table 10.8 Potential Environmental Effects in the Southern Watersheds
Table 10.9 Potential Environmental Effects within the North Tailings Basin Watershed
Table 10.10 Potential Environmental Effects Within Pond 65 Watershed
Table 10.11 Potential Environmental Effects within the Throat Bay Watershed
Table 10.12 Potential Environmental Effects within the Option 5 Watershed
Table 10.13 Potential Environmental Effects within the Pond 67 Watershed
Table 10.14 Potential Environmental Effects within the Little Reid Brook Watershed and Port Site Drainage
Table 10.15 Summary of Predicted Pond Water and Tailings Pore Water¹
Table 10.16 Headwater Pond Seepage
Table 10.17 Water Quality in Camp Pond - Median Baseline Conditions and Predicted Increases
Table 10.18 Seepage at North Tailings Basin Dam N2
Table 10.19 Water Quality in North Tailings Basin Brook, Directly Below Dam N2 - Baseline Median Conditions and Predicted Increases
Table 10.20 Seepage at Dam H1
Table 10.21 Water Quality in the Throat Bay Watershed, Directly Downstream of Dam H1, Median Baseline Conditions and Predicted Increases
Table 10.22 Seepage at Dam N6
Table 10.23 Water Quality, Directly Downstream of Dam N6 (Option 5 Watershed) - Median Baseline Conditions and Predicted Increases
Table 10.24 Seepage at Dam N3
Table 10.25 Water Quality, Directly Downstream of Dam N3 (Pond 67 Watershed) Median Baseline Conditions and Predicted Increases
Table 10.26 Accidental Events - Summary of Environmental Effects
Table 10.27 Range of Values of Various Metals for Establishing Criteria for the Evaluation of the Significance of Residual Environmental Effects (mg/L)
Table 10.28 Summary of Residual Environmental Effects in Headwater Tailings Basin and North Tailings Basin
Table 10.29 Summary of Residual Environmental Effects Downstream of Headwater Pond in the Reid Brook Watershed
Table 10.30 Summary of Residual Environmental Effects in the Southern Watersheds
Table 10.31 Summary of Residual Environmental Effects Downstream of Dam N2 in the North Tailings Basin Watershed
Table 10.32 Summary of Residual Environmental Effects in Pond 65 Watershed
Table 10.33 Summary of Residual Environmental Effects Downstream of Headwater Pond in the Throat Bay Watershed
Table 10.34 Summary of Residual Environmental Effects in Option 5 Watershed
Table 10.35 Summary of Residual Environmental Effects in Pond 67 Watershed
Table 10.36 Summary of Residual Environmental Effects in Little Reid Brook Watershed and Port Site Drainage