1. Environment Canada’s Intervention on the Meadowbank Gold Project Water Licence Public Hearing
Good afternoon __________ Chair, and members of the Board.
Introductions
Acknowledge team: Ivy, Wade, Dave
Anne Wilson/Glenn Groskopf
Environmental Protection Operations
April 14-17, Baker Lake, NU

2. Overview Mandate Water Quality & Groundwater issues
Tailings and Waste Rock Management
Waste Management
Emergencies
Closure and Reclamation
Conclusion

3. Mandate and Role
The primary relevant legislation and standards administered or adhered to by EC which influenced the content of this submission are:
Section 36(3) of the Fisheries Act – Pollution Prevention Provisions;
Metal Mining Effluent Regulations;
Canadian Environmental Protection Act (CEPA);
Canada-wide Standards for Mercury Emissions; and
Canada-wide Standards for Dioxins and Furans.
See Appendix A of intervention submission if further detail required.

4. Water Quality Issues Issues include: Lake dewatering
Monitoring programs
Effluent quality criteria
Water quality predictions
Pit lakes
Groundwater monitoring

5. Lake Dewatering
Issue: Dewatering discharges will be controlled by the amount of sediments in the water. EC has specific comments on monitoring and proposes use of turbidity as a regulated parameter.
Recommendations: EC supports the approach outlined by AEM to use thresholds for stopping discharge and/or triggering management actions. EC also recommends use of discrete samples, use of a 6-day average for TSS, regulation of other parameters in addition to TSS (i.e. turbidity, aluminum, pH), and submission of a dewatering plan as a condition of the water licence.

6. Water Quality Monitoring Programs
Issue: Required monitoring will include compliance monitoring (SNP), receiving environment monitoring (AEMP) and MMER EEM monitoring. Ongoing groundwater monitoring is also an important aspect of water management and closure planning.
Recommendations: All monitoring requirements should be harmonized in a consolidated plan, with construction-phase Sampling and Analysis Plans developed as soon as possible for approval by the NWB. Groundwater monitoring should be described in a stand-alone plan which includes schedules and rationale for well installations.

7. Site Water Quality Monitoring
Issue: EC has identified some specific concerns with the proposed water quality monitoring. Details are outlined in our intervention.
Recommendations: AEM has proposed a good framework for site water quality monitoring, but this should be further developed and submitted to the NWB for approval.
Re: diffuser discharge stations (CM-4 and CM-5) these are compliance points for the water licence, results will be linked to the interpretation the AEMP so a broad suite of analyses is needed to characterize these effluents. This is also required (to a somewhat lesser degree) under the MMER effluent characterization (compulsory plus recommended parameters). Monitoring should be done in advance of discharge, as well as weekly during discharge.
A full suite of parameters should be analyzed for the diffuser discharges, including total and dissolved metals (full ICP scan), nutrients, TDS, major ions, TSS, turbidity, and total petroleum hydrocarbons. (This would be Schedule 4 plus TPH and turbidity).
Other modifications recommended include:
Monitored sites for diversion of non-contact waters should include aluminum, and it should not be necessary to measure cyanide (included in Schedule 5).
The tailings storage facility (CM-6) parameters should include analysis for nitrogen compounds, but should not require cyanide compounds.
The pit lake discharge points (CM-7 and CM-8) should be monitored for a full suite of parameters.
For the waste rock pile monitoring (IM-2 and IM-10), the Schedule 3 parameters should be amended to include total metals as well as dissolved.
The pit lake sites (IM-3, IM-5, IM-6 and IM-12) should be monitored for Schedule 4 parameters to give a good understanding of how water quality is developing as the pit lakes fill. This will allow time for mitigation to be developed if necessary.
The two tailings monitoring sites (IM-7 and IM-8) should also be monitored for cyanide and total metals in addition to the Schedule 3 parameters.
The Vault Attenuation Pond (IM-11) should have total metals measured also.
To be consistent with the MMER, Radium 226 could be added to the MMER list, although this is not a parameter of concern for this project.

8. Effluent Quality Criteria
Issue: Proposed effluent quality criteria have been drafted by the proponent, and EC has suggested additional and/or more conservative criteria in some cases, and suggests only monitoring for other parameters.
Recommendations: Appendix B of EC’s intervention outlines our recommendations for discharge criteria, including:
Turbidity be regulated for discharges from the dewatering areas and attenuation ponds;
Chloride be regulated at lower levels;
Sewage-associated parameters be regulated for discharges to surface waters.
Receiving waters in the project area contain very low concentrations of all parameters, and are ultra-oligotrophic with respect to having low nutrient levels and productivity. Ecosystems are based on very simple food webs, and as such are vulnerable should impacts occur to any compartment of the ecosystem. A very high level of protection is warranted when discharging effluent into such a pristine system.
The proposed criteria for surface runoff of 50 mg/L (average) or 100 mg/L (grab) are consistent with other licences issued in both Territories. However, EC notes that effects associated with suspended solids are a function of both exposure and duration. If these limits are used, there would be the expectation that duration would be minimized and that management action would be taken to protect the more productive littoral areas of lakes from sedimentation. This could be achieved either through defining a duration for the criteria, or through management plans (most practical).
high potential for the suspension of very fine materials in the discharge water during dewatering (due to high clay content in the lake sediments). These fines would pass unmeasured through the 1.4 µm filter that is used for suspended solids, thus not triggering the limits for suspended solids, but adding significant suspended matter to the receiving lake. Such fines remain suspended in the receiving water column for periods on the order of weeks. The resulting loss of water clarity would reduce sunlight penetration, and diminish algal production, resulting in lowered primary productivity. We do have the precedent of Diavik’s dewatering of their in-lake diked area for their two pits, and in this case the turbidity limit was the limiting factor for what could be discharged. Their limits were 10 NTU average/ 15 NTU grab, and the environmental manager acknowledged that even though they were below the TSS limits, the change in water clarity could easily be seen when approaching the turbidity limit (Gord MacDonald, personal communication).
We note that the Tahera licence has a limit of 500 mg/L for chloride, while Ekati’s proposed site-specific limit of 1332 mg/L to achieve mixing zone concentrations of 313 mg/L has been rejected by most stakeholders as being too high. Given the seasonal nature of the discharge, and the 64-fold dilution for Portage, it may be reasonable to set chloride limits on the order of 1000 mg/L (average) which would give mixing zone concentrations of under 16 mg/L, and conduct monitoring to identify fate and behaviour in the receiving environment. The predicted discharge concentration of 441 mg/L (possible poor-end scenario) gives room for variation in effluent quality.

9. Water Quality Predictions
Issue: There is some uncertainty regarding the modeling of nitrogen compounds from cyanide breakdown, and regarding the levels of ammonia which will accumulate in the attenuation pond and reclaim pond. AEM will monitor and periodically re-model.
Recommendations: EC supports AEM’s approach, and recommends periodic recalibration of the water quality modeling be a licence condition. We also recommend rigorous source control of amounts of cyanide and ammonia through implementation of an approved ammonia management plan.

10. Pit Lakes Water Quality
Issue: EC has concerns with the evolution of pit water quality due to unknowns with groundwater discharges, and uncertainty around the formation and persistence of chemoclines in the pit lakes.
Recommendations: EC seeks clarification of the role of groundwater inputs/discharges in the evolution of pit water quality, and an evaluation of the stability of meromixis, and how that will affect water quality at closure. Updating and re-running of the pit water quality model should be done once further groundwater quality data are available.

11. Groundwater Monitoring
Issue: EC had identified several problems with the handling of groundwater data, although we did agree data were adequate to predict salinity and major ion concentrations and dissolved metals.
Recommendations: Development and implementation of a comprehensive groundwater monitoring plan which addresses data presentation concerns, including installation of more robust permanent monitoring wells as soon as possible, is recommended.

12. Tailings and Waste Rock Issues
Issues include:
Design depth of the long-term active zone
Waste rock pile management
Till characteristics
Mine rock segregation

13. Design Depth of the Long-term Active Zone
Issue: Problematic mine solid wastes must be encapsulated in perpetuity, global warming notwithstanding. AEM has committed to a minimum two meter rock cover over reactive rock, tailings, and overburden to confine the active layer, and will instrument to monitor freezeback efficiency and cap performance.
Recommendations: EC recommends that AEM’s commitments be included in a rock management plan, to be updated periodically as data are collected and reported.

14. Contingency Planning for Waste Rock Piles
Issue: Specific contingencies have not been presented should early work on the waste rock piles indicate freezing would not be sufficient to isolate potentially problematic rock types.
Recommendations: AEM should be required to periodically review and document the performance of its monitoring systems, of segregation methods, evolving water quality, cover material requirements, and of relevant technology developments and study results.
Such ‘State of the Environment Reporting’ or roll-up reporting has been the practice at other mines. Monitoring results should be compared to EIS predictions and observed differences explained; procedures, designs and measures undertaken in response to unanticipated circumstances should be documented; and improved predictions of environmental performance presented. This reporting would demonstrate the implementation of continuous improvement and adaptive management, and could be done on a triennial basis.

15. Till Characterization
Issue: Although most till materials will be non-ARD generating, there are exceptions in soils above the ore deposit. AEM commits to testing the till prior to use in any environmentally sensitive structures, screening against the most stringent federal and territorial criteria for soils.
Recommendations: EC recommends that test results be reported to the Board on an annual basis as part of a rock management plan.
The proposed measures would address the concerns identified with use of potentially problematic till.
Reporting could include a description of measures used to ensure segregation of any potentially problematic material.

16. Site Mine Rock Segregation
Issue: Segregation of rock will be done based on sulfur content for ARD potential, and total metal content for metals leaching potential. AEM is committed to updating and adapting the plan as mining advances and additional data is obtained.
Recommendations: A credible segregation system should be in place prior to excavation and based on best current understanding. During mine development, criteria of a conservative measure should be employed. The segregation system should be audited periodically to affirm it continues to operate effectively as designed.

17. Waste Management Waste management issues include:
Incineration management
Compliance with Canada-wide Standards
Landfarm operations

18. Waste Incineration
Issue: AEM plans to incinerate used petroleum products, food waste and sewage treatment sludge and has committed to use a dual chamber, high temperature incinerator (yet to be selected). Incinerator ash will be disposed of by spreading within the landfill following limited testing for compliance with the Environmental Guideline for Industrial Waste Discharges (GN, 2002). Compliance with the CWS will be demonstrated through monitoring and stack testing.
Recommendations: EC recommends inclusion of the incineration management plan as a licence requirement, with reporting of test results in the annual reports. Best practices should be implemented for ash disposal.

19. Landfarming of Contaminated Materials
Issue: AEM has satisfactorily addressed concerns previously identified with the landfarm operations.
Recommendations: Areas of concurrence between EC’s recommendations and AEM should be documented for future follow-up, perhaps in the form of adding to a commitments list, or as an addendum to the plan.

20. Emergencies
Issue: AEM has addressed concerns identified with the Hazardous Material Management Plan and revisions to the Spill Contingency Plan.
Recommendations: Areas of concurrence between EC’s recommendations and AEM should be documented for future follow-up, perhaps in the form of adding to a commitments list, or as addenda to the plans.

21. Closure and Reclamation
Closure issues include:
Removal of dewatering dykes
Post-closure monitoring
Closure of treatment plant facilities
Progressive closure of the rock storage facilities

22. Removal of Dewatering Dikes
Issue: AEM is committed to ensuring appropriate mitigation measures are identified and implemented prior to initiation of breaching dikes, and these will be detailed in a plan submitted to the NWB in advance of the work.
Recommendations: EC recommends the licence require submission of detailed information regarding the method to be used to remove/breach the dewatering dikes at least 18 months prior to commencing this work. Potential impacts of the chosen method should be discussed and mitigation measures identified.

23. Post-closure Monitoring
Issue: Monitoring is being developed as part of an Operation, Maintenance and Surveillance Manual, and the manual will incorporate recommendations made by EC at the Pre-hearing technical meetings.
Recommendations: EC recommends that the OMS Manual be updated periodically in conjunction with the closure plans, and circulated for review.

24. Closure of Treatment Plant Facilities
Issue: A water treatment plant is likely to be required, and details on closure of this facility could be provided on a general basis. For example, if the mill is modified to include a treatment circuit at closure how would this affect timing and details of decommissioning?
Recommendations: Details on how any such facility would be decommissioned should be included in future updates to the closure and reclamation plan.

25. Progressive Closure of Rock Storage Facilities
Issue: AEM has committed that a detailed monitoring and instrumentation plan will be prepared and submitted to the NWB for review once a final waste rock deposition plan has been developed.
Recommendations: EC recommends that submission of monitoring plans be a licence requirement, with results linked to closure planning.

26. Conclusion
EC would like to thank the NWB for the opportunity to participate in the water licence process for the Meadowbank Gold Project.
We would also like to thank the proponent for a constructive and interactive approach which has helped resolve concerns ahead of this hearing.