HAMMOND REEF GOLD PROJECT Final EIS/EA Report Part 1: Response to Comments from Federal Regulators

Transcription

1 June 2015 HAMMOND REEF GOLD PROJECT Final EIS/EA Report Part 1: to Comments from Federal Regulators Project Number:

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3 FINAL EIS/EA REPORT RESPONSE TO FEDERAL COMMENTS TABLE OF CONTENTS Reference # Discipline Reference # Discipline T-1 Project Description T-2 Alternatives Assessment T-3 Mine Waste Disposal Alternatives Assessment T-4 Mine Waste Disposal Alternatives Assessment T-5 Mine Waste Disposal Alternatives Assessment T-6 Mine Waste Disposal Alternatives Assessment T-7 Mine Waste Disposal Alternatives Assessment T-8 Mine Waste Disposal Alternatives Assessment T-9 Mine Waste Disposal Alternatives Assessment T-10 Mine Waste Disposal Alternatives Assessment T-11 Human Health and Ecological Risk Assessment T-12 Atmospheric Environment T-13 Atmospheric Environment T-14 Atmospheric Environment T-15 Atmospheric Environment T-16 Atmospheric Environment T-17 Atmospheric Environment T-18 Atmospheric Environment T-19 Atmospheric Environment T-20 Atmospheric Environment T-21 Atmospheric Environment T-22 Water Quality T-23 Human Health and Ecological Risk Assessment T-24 Human Health and Ecological Risk Assessment T-25 Hydrology T-26 Project Description T-27 Geochemistry, Geology and Soils T-28 Water Quality T-29 Geochemistry, Geology and Soils T-30 Geochemistry, Geology and Soils T-31 Geochemistry, Geology and Soils T-32 Geochemistry, Geology and Soils T-33 Geochemistry, Geology and Soils T-34 Geochemistry, Geology and Soils T-35 Hydrogeology T-36 Water Quality T-37 Water Quality T-38 Water Quality T-39 Water Quality T-40 Hydrogeology T-41 Hydrogeology T-42 Hydrogeology T-43 Water Quality T-44 Project Description T-45 Water Quality T-46 Water Quality T-47 Water Quality T-48 Water Quality T-49 Project Description T-50 Water Quality T-51 Water Quality T-52 Hydrology T-53 Terrestrial Ecology T-54 Closure T-55 Terrestrial Ecology T-56 Aboriginal T-57 Aboriginal T-58 Hydrology T-59 Socio-economic Environment June 2015 Project No Hammond Reef Gold Project i

4 FINAL EIS/EA REPORT RESPONSE TO FEDERAL COMMENTS Reference # Discipline T-60 Project Description T-61 Project Description T-62 Project Description T-63 Cultural Heritage Resources T-64 Cultural Heritage Resources A-1 Water Quality A-2 Atmospheric Environment A-3 Atmospheric Environment A-4 Other A-5 Terrestrial Ecology A-6 Terrestrial Ecology A-7 Mine Waste Disposal Alternatives Assessment A-8 Atmospheric Environment A-9 Atmospheric Environment A-10 Atmospheric Environment A-11 Water Quality June 2015 Project No Hammond Reef Gold Project ii

5 COMMENT T-1 Although Osisko [Canadian Malartic Corporation] provided a response to CEAA -7 on the draft EIS/EA Report, it does not provide enough detail to understand the environmental effects from the proposed aggregate pits. The locations of the proposed aggregate pits are also not known. The response to CEAA-8 also does not provide enough information to understand the potential effects of potential new roads to aggregate pits that may be used for the construction of the mine site. Provide an assessment of other prospective aggregate pits and a map with the locations of the proposed aggregate pits. Describe the potential effects of potential new roads to aggregate pits that may be used for the construction of the mine site. Appendix1.IV, IR CEAA-7, CEAA-8 There are currently sufficient aggregate resources nearby which can supply Project needs. It is Canadian Malartic Corporation s intent to identify (including mapping) additional locations at such a time as Canadian Malartic Corporation is ready to apply to develop and permit these resources to limit potential for speculative bidding for resources. Canadian Malartic Corporation would follow all appropriate permitting regulations under the Aggregate Resources Act. Canadian Malartic Corporation currently holds permits under the Aggregate Resources Act for 3 existing aggregate pits in the vicinity of the Project, and these aggregate pits would remain in use. Canadian Malartic Corporation has also identified other prospective sources to address some of the additional aggregate requirements. In due course, they may apply for permits for one or more of these prospective sites; however no decision has yet been made in this regard. New access roads would likely be required in connection with any of these possible new aggregate pits. Impacts due to new access roads have not been addressed in the Final EIS/EA for the mine. These impacts are expected to be minimal and would be addressed under permitting as would be required for any other aggregate resources under the Aggregate Resources Act. Depending on commercial and permitting considerations, (i.e. haul distance, purchase costs, royalties, etc.), Canadian Malartic Corporation may address additional requirements by either purchasing aggregate from commercial sources or by crushing waste rock on site. In this case, no new access roads or road upgrades would be required. Canadian Malartic Corporation holds Category 9 permits on the existing aggregate pits, which means that the pits are located on Crown land and they are not to be operated closer than 1.5 m above the established water table. It is expected that any new aggregate pits would also be permitted under Category 9. No aggregate can

6 be extracted from below the water table, and any runoff from rainfall can be contained within the pit area where it will infiltrate. Good practice measures, such as leaving a high point on the access road, will be followed to prevent any runoff leaving the sites of any of the aggregate pits. For this reason, the aggregate pits are not expected to have any impacts on lake water quality. 2 Project No

7 COMMENT T- 2 The reasoning for environmental effects does not appear to be consistent. The section claims: a) Areas along a roadway will minimize vegetation clearing b) Alternative 3 is not solely along a roadway and will require clearing of new areas. c) Alternative 3 is the shortest of the three alternatives and will require the least vegetation clearance. It is not clear why Alternative 1, which does not require any new right of way to be cleared, has more vegetation clearance than Alternative 3. It appears this decision was solely based on economics, not also on environmental reasons as the report implies. Clarify the reasoning used to choose Alternative 3. Alternatives Assessment TSD pages The preferred Project transmission line alignment is Alternative 3 Hardtack/Sawbill Road across Sawbill Bay. The selected transmission line alignment will follow the upgraded Hardtack Road and Sawbill Road for the first 16 km then make a 2.3 km crossing to the Ore Processing Facility, for a total length of approximately 20 km. An estimated 85 towers will be required for the transmission line, including wood (H-frame) structures for the first 14 km and larger steel towers for the remaining distance to allow for the longer spans across Sawbill Bay.

8 The comment is correct in stating that Alternative 3 will require more clearing than Alternative 1, however the total amount of clearing is not considered significant. The manner in which the transmission line Right of Way is constructed is also anticipated to reduce environmental effects associated with land clearing. The pathway of the transmission line will be cleared but not graded and stripped of topsoil to allow for quick regrowth of vegetation in the transmission corridor. The comment is correct in stating that economic considerations were important to the selection of Alternative 3 as the preferred alternative. The option of the transmission line crossing Sawbill Bay significantly reduces the length of the line, and in turn, the overall cost of installing the transmission line. As the Project transmission line will be strung across the bay, the potential effects to water quality and aquatic habitats will be minimized. The change to the visual landscape is expected to be a concern that will be addressed through ongoing work with the community. The changes to visual landscape will be fully reversible during mine closure because the infrastructure will be decommissioned. 2 Project No

9 COMMENT T-3 On Figure 4-9, a fourth option for the tailings management facility is shown, however it appears that this should be WRMF 4. Confirm that the feature in Figure 4-9 is a waste rock stockpile alternative and not a tailings alternative. EIS Figure 4-9, page 4-65 In Figure 4-9, the feature identified in the legend as Alternative 4 under the Tailings Management Facility heading is a Waste Rock alternative and should be under the Waste Rock Management Facility heading.

10 COMMENT T-4 In the Alternatives Assessment for Mine Waste Disposal, several inconsistencies were noted in the data for the footprint of the tailings management facility, the length of the pipeline, and the height of the tailings management facility. For example, the footprint for TMF 1, TMF 2 and TMF 3 are stated as 8.6 M-m2, 9 M-m2 and 8.3 M-m2, respectively, on page 15 whereas they are stated as 860 ha, 900 ha and 813 ha, respectively, on page 25. In addition, under the Geotechnical Risk indicator (page 36), the Proponent used the maximum height of dams as the metric, with the dam heights for TMF 1 and TMF 2 given as a range (20-30 m and m, respectively) and that for TMF 3 as a single value (32 m). The rationale for this is not clear. Furthermore, under the Maximum Height of TMF indicator (page 43), the Proponent has used the maximum TMF height as a metric with a different scale and stating that the dams associated with TMF 1, TMF 2 and TMF 3 will be up to 35 m, 45 m and 32 m, respectively. The scores for this indicator could potentially change if the same scale for maximum TMF height as used in page 36 for the Geotechnical Risk indicator was used here. Correct the inconsistencies and revise the multiple accounts analysis to determine if any changes in the conclusion would result. Clarify whether or not the scores for the indicator could potentially change if the same scale was used for the Geotechnical Risk indicator as was used for the Maximum Height of TMF indicator. Appendix 4.1 Mine Waste Disposal Alternatives Assessment Version 2 Pages 25, 15, 36, 43 The inconsistencies in design and measurements found within the Mine Waste Alternatives Assessment Report are related to the ongoing and iterative planning process. Footprint Area The TMF alternative descriptions on page 15 were developed in January 2012 during the Terms of Reference stage for pre-screening purposes. Through this initial pre-screening assessment, Alternative TMF-1, Alternative TMF-4, and Alternative TMF-2 were considered to be viable alternatives and were carried forward for more detailed assessment. For simplicity in the detailed assessment, an alternative naming scheme was used in which: Alternative TMF-1 was carried forward as TMF-1; Alternative TMF-4 was carried forward as TMF-2; and Alternative TMF-2 was carried forward as TMF-3 (base case).

11 The TMF-3 (base case) concept was revised after the pre-screening assessment based on additional engineering to reduce the dam volume, footprint area and cost. Through this effort, the footprint area of Alternative TMF-3 was reduced to 8.13 M-m 2 (or 813 ha) compared to the description provided in the ToR (page 15). The other alternatives maintained the same footprint areas compared to the description in the ToR (page 15). Pipeline Lengths The pipeline lengths included in the descriptions on page 15 were preliminary estimates for pre-screening purposes. After the viable candidates were identified, additional work was undertaken to estimate conceptual pipeline routes for the alternatives based on engineering and environmental considerations (e.g., topography and proximity to waterbodies), the location of relevant mine infrastructure (e.g., processing plant, utility corridors) and the centroid of the TMF area. For these reasons, the pipeline lengths identified in the detailed assessment are different from those in the preliminary pre-screening description. Dam Height At the time of the assessment, the engineering design of TMF-3 had advanced further compared to TMF-1 and TMF-2. For this reason, a discrete maximum dam height of 32 m had been defined for TMF-3, while the maximum heights for TMF-1 and TMF-2 remained as ranges. Had the height of TMF-3 been described as a range of m, it would have been assigned the same score and the results would remain the same. Maximum TMF Height The maximum height of TMF indicator considers both the height of the dams and the height of the tailings stack inside the dams. The maximum height of TMF-1 was estimated incorrectly using a maximum dam height of 35 m. As per the Geotechnical Risk indicator, the maximum dam height is up to 30 m and this would result in a potential maximum tailings height of 62 m (compared to 67 m as estimated in the assessment). With this maximum height TMF-1 would have been assigned the same score and the results would remain the same. Conclusion With respect to footprint area and pipeline length, it is acknowledged that the values used in the assessment are not consistent with the preliminary estimates assumed in the pre-screening assessment. The detailed alternatives assessment was carried out using the best information available at the time. With respect to the dam heights, it is acknowledged that minor inconsistencies exist in the values and ranges presented in the assessment but the magnitude of these inconsistencies is small and does not affect the outcome of the assessment. 2 Project No

12 COMMENT T-5 It appears that for the indicator Ability to Limit Impacts to Water Quality in Surrounding Water bodies (sections and ) the Proponent has inverted the scoring scale, which should go from Low to High rather than from High to Low. Clarify whether this is a typographical error. Appendix 4.1 Mine Waste Disposal Alternatives Assessment Version 2 The indicator Ability to Limit Impacts to Water Quality in Surrounding Water Bodies is a measure of the TMF locations ability to mitigate impact. The scoring scale for this indicator is correct. Key considerations for this indicator are topographic containment, proximity to waterbodies and number of potential discharge pathways. For example, TMF-3 is located against a topographic high (to the northwest) and has topographic features that limit potential water release to three receiving locations. The TMF-2 location provides no topographic containment and has the potential to release water to up to eight receiving locations. Therefore, TMF-2 is considered to have a lower ability to limit impact to water quality in surrounding water bodies compared to TMF-1 and is assigned a lower score.

13 COMMENT T-6 It was noted that there are several indicators where the score is the same for all options (e.g., section Dam Hazard Classification). Clarify why an indicator that had the same score for all alternatives was used. Appendix 4.1 Mine Waste Disposal Alternatives Assessment Version 2 Where the potential existed for an indicator to differ between alternatives, it was evaluated and included in the multiple accounts analysis to document that the indicator had been considered. (This is in contrast to the nondifferentiating indicators that are discussed in Section 3.4.5, which are indicators where no difference between the candidate sites is even possible, given the general site conditions.) In the example cited in the comment (Dam Hazard Classification), the indicator considers localized factors such as the potential for loss of life and loss of infrastructure, therefore the potential existed for this indicator to differ among alternatives. For this reason, it was evaluated and included in the assessment. The inclusion of indicators with the same score does not affect the final ranking of the alternatives because the indicator scoring contributes equally to the final score for each alternative. Potential indicators that were truly non-differentiating (e.g., potential for acid rock drainage, potential for metal leaching, seismic risk) were not included in the multiple accounts analysis.

14 COMMENT T-7 The indicator Impact to Groundwater seems to be more of a technical sub-account. The description of the indicator focuses on the management of the seepage collection ponds. There does not appear to be a direct link to groundwater quality for this indicator. In the multiple accounts analysis of the Alternatives Assessment for Mine Waste Disposal, include the use of other metrics (e.g. hydraulic conductivity of the domain, depth to the bedrock, as well as depth to the groundwater, perched water tables and presence of springs) as described in the EIS Guidelines for the impact to groundwater indicator. Appendix 4.1 Mine Waste Disposal Alternatives Assessment Version 2 At the TMA-3 (base case) location, there has been some characterization of the detailed hydrogeological information necessary to evaluate the suggested metrics (hydraulic conductivity, depth to the bedrock, groundwater depth, etc.). This type of information is not available for the other alternative locations. Therefore, an evaluation and comparison of the hydrogeological conditions could not be fully completed using the suggested metrics. Canadian Malartic Corporation has committed to installing seepage collection systems for the mine waste disposal areas and these systems will be designed, based on site specific conditions, to collect and capture seepage. The general foundation conditions for the alternatives have been considered and deemed feasible for construction of a TMF and effective seepage collection system. With these collection systems in place, the relative potential for groundwater release to the environment is related mainly to the complexity of the collection system. In the evaluation of this indicator, it is considered that the complexity of the collection system increases with the number of required collection ponds. Therefore, the relative potential for groundwater release to the environment is evaluated based on the number of collection ponds required by the collection system.

15 COMMENT T-8 The analysis of impact to aquatic habitat sub-account is not clear. There are several indicators that could be potentially useful for inclusion in the multiple accounts analysis, notably the area of streams instead of the length of streams, the number of fish species and the size of the fish population that are going to be impacted by project footprint. The impact to downstream area due to a dam failure should be assessed in a separate subaccount. Consider additional indicators as mentioned in the previous column. Indicate the source (reference or supporting document) of the metrics used for various indicators in the Aquatic Habitat sub-account. Appendix 4.1 Mine Waste Disposal Alternatives Assessment Version 2 Throughout the Draft EIS/EA Report review process, several indicators were added to the assessment based on direct review and comments from Environment Canada. Following a meeting between Canadian Malartic Corporation, Golder and the Government Review Team on July 23, 2013 regarding the Mine Waste Alternatives Assessment, the list of indicators for use in the multiple accounts analysis was expanded. The proposed indicators for assessment of the potential impact to the aquatic habitat were expanded to include: Number of streams crossed by the tailings pipeline (for assessment of the Tailings Management Facility (TMF); Number of streams crossed by the haul road (for assessment of the Waste Rock Management Facility (WRMF); and Area of streams and water bodies impacted. The proposed list of indicators was sent to representatives from Environment Canada (EC) for review and comment. In their review comments, EC suggested the following indicators be added to the assessment: Permanent streams impacted; Ephemeral streams impacted; Indirect impacts such as downstream flow reductions; Number of fish-bearing lakes affected; and Area of fish-bearing lakes affected.

16 In accordance with EC s request, these new indicators were added to the aquatic habitat assessment. The indirect impacts resulting from downstream flow reductions are implicitly considered within the existing aquatic habitat indicators by considering a stream or lake impacted if its watershed was reduced by 25% or more by the proposed alternative. Evaluation by fish species and population was not included because it was not requested as an additional aquatic habitat indicator by Environment Canada. The definition of permanent/ephemeral streams was obtained from Table 7-1 of the Hydrology TSD. The fish bearing classification of the lakes was obtained from Table 2-6 of the Aquatic Environment TSD. The lake areas were measured based on the available site hydrography. In terms of stream width, in many instances, streams were not distinguishable during baseline surveys or did not have defined channel bed/banks to support width measurements. Therefore, the evaluation of stream by stream length was selected because stream width data was not available for all streams. The assessment of impact to downstream habitat due to a dam failure is not assessed in the potential impact to the aquatic habitat sub-account. It is addressed in the dam hazard classification indicator under the technical account which considers the potential environmental impact due to failure. Canadian Malartic Corporation met with Environment Canada, shared our list of proposed indicators and modified these indicators based on Environment Canada s requests. It is considered that the indicators presented in the Final EIS/EA Report for the aquatic habitat sub account reasonably capture the potential for impact to aquatic habitat by the mine waste facilities. A sensitivity analyses was carried out to evaluate potential for bias in the account, sub-account and indicator weighting and the preferred alternative did not change for either the TMF or WRMF through this analysis. 2 Project No

17 COMMENT T-9 The following observations were noted on the Proponent s assessment of alternatives for waste rock: The indicator Effects on Wildlife with the metric Distance from mine pits (page 68) has exactly the same outcome (same scale and score) as the indicator Haul Road Distance with the metric Length of haul roads which was used to assess the noise impacts (page 75). Under the indicator Impact to bird habitat, the Proponent has assessed the various alternatives using only the area of wetland directly impacted. There is no consideration of the full potential impact on birds or various bird species. Distances to water bodies is not defined but rather the term close is used frequently to describe location or proximity to water but actual distance is not defined which means that all alternatives score the same. Clarification of these items will provide confidence on whether or not there would be any changes to the conclusions. Clarify the observations noted above. Appendix 4.1 Mine Waste Disposal Alternatives Assessment Version 2, page 68, 75 Comment: The indicator Effects on Wildlife with the metric Distance from mine pits (page 68) has exactly the same outcome (same scale and score) as the indicator Haul Road Distance with the metric Length of haul roads which was used to assess the noise impacts (page 75). The potential effects on wildlife are considered to be mainly the result of a change to habitat suitability due to additional sensory disturbance (i.e., light, noise, dust, human presence). The area near the mine pits is considered to be the main source of sensory disturbance factors and habitat suitability is considered to increase with distance away from the mine. Therefore, a mine waste disposal area located close to the mine pits is considered to pose less potential incremental impact to wildlife in comparison to more distal locations where the introduction of a WRMF would introduce sensory impacts into an area that is otherwise relatively undisturbed. In addition, the haul road itself will introduce sensory impacts, since a longer haul road would cause sensory disturbance along a longer corridor and would require longer truck cycles. The metric used to evaluate this indicator is distance to the mine pits. The potential for noise generation (as a component of the physical environment) due to the WRMF is related to the vehicle distance travelled to haul the waste rock to the stockpile. A longer haul road would result in longer truck cycle times which would require that more trucks be in operation. A shorter haul road is therefore considered to generate less noise. For cost considerations, it is preferable to minimize the haul distance from

18 the pit to the stockpile. (The haul road distance is assumed to be directly related to the distance from the stockpile to the mine pits). The potential for noise generation was not evaluated in the TMF assessment because the TMF is not considered to be a significant noise source. Comment: Under the indicator Impact to bird habitat, the Proponent has assessed the various alternatives using only the area of wetland directly impacted. There is no consideration of the full potential impact on birds or various bird species. The WRMF and TMF assessments qualitatively evaluated the potential for impact to bird habitat based on an ecologist s interpretation of the following considerations: The amount of wetland habitat directly affected (the diversity of available bird habitat, other than wetland habitat, was not considered to vary significantly between alternatives); The potential interruption to travel corridors near open water areas due to the high stockpile (considered for the WRMF only); and, The potential for sensory disturbance (noise, light, human presence). Although the presence of wetlands is important to bird habitat, the evaluation considered more than only the area of wetland directly impacted. Comment: Distances to water bodies is not defined but rather the term close is used frequently to describe location or proximity to water but actual distance is not defined which means that all alternatives score the same. For indicators that use distance a specific water body as the metric, (e.g., the distance to Marmion Reservoir indicator) the distance is provided. For qualitatively evaluated indicators that consider proximity to water bodies as one of several factors (e.g., the potential impact to bird habitat indicator), a qualitative description is provided in the report. Although considered in the evaluation and selection of the scoring selection, the exact distance to nearby water bodies was not the only consideration for these indicators. Additionally, the qualitative descriptions of proximity provided in the report are not always in reference to the same water body, therefore they are not directly comparable without professional interpretation and consideration of the other factors important to each indicator. 2 Project No

19 COMMENT T-10 The Ontario Ministry of the Environment notes discrepancies in the scoring of alternatives related to hydrogeology. The impact to groundwater is scored on the number of ponds estimated to be needed for seepage collection, and there is no consideration that soil type and overburden depth have been considered, even though these factors have significant impact on the ability to monitor and/or control seepage and/or implement mitigative measures and contingencies. The proponent has not adequately addressed the initial concern in GW-05 regarding the impact of soil conditions on the assessment of alternative sites, and may not have properly assessed the alternatives for TMF location with respects to the potential for groundwater impacts. Unrelated to the above, in Section which is based on the distance of the facility to Marmion Basin, TMF 1 and TMF 3 are not scored equally although they are virtually the same location, and therefore both lie within the same distance of the Marmion Reservoir. An explanation is required for the differences in score. Re-evaluate the alternatives assessment for the tailings management facility with respect to soil type and conditions in relation to groundwater impacts, and overburden depth, to confirm selection of the preferred alternative. Consideration should be given to Lizard Lake in the assessment. Provide an explanation on the difference in scores with TMF1 and TMF3 even though both facilities lie within the same distance of the Marmion Reservoir. 4.2, Alternatives Assessment TSD, Section Appendix 4.1, section , , , At the TMA-3 (base case) location, there has been some characterization of the detailed hydrogeological information necessary to evaluate the suggested metrics (hydraulic conductivity, depth to the bedrock, groundwater depth, etc.). This type of information is not available for the other alternative locations. Therefore, an evaluation and comparison of the hydrogeological conditions could not be fully completed using the suggested metrics. Canadian Malartic Corporation has committed to installing seepage collection systems for the mine waste disposal areas and these systems will be designed, based on site specific conditions, to collect and capture seepage. The general foundation conditions for the alternatives have been considered and deemed feasible for construction of a TMF and effective seepage collection system. With these collection systems in place, the relative potential for groundwater release to the environment is related mainly to the complexity of the collection

20 system. In the evaluation of this indicator, it is considered that the complexity of the collection system increases with the number of required collection ponds. Therefore, the relative potential for groundwater release to the environment is evaluated based on the number of collection ponds required by the collection system. With respect to the distance from Marmion Reservoir indicator (under the visual impacts sub-account), the evaluation also considered Lizard Lake because it is also used for recreational purposes. It is acknowledged that the indicator should have been identified as Distance from Recreational Water Bodies. In the assessment completed, the preferred alternative (TMF-3) was assigned a lower score because it is closer to either Marmion reservoir or Lizard Lake compared to TMF-1. If Lizard Lake is removed from the evaluation, TMF-1 and TMF-3 would receive the same score. This would result in a higher overall score for the TMF-3 (the preferred alternative) and the final result would remain the same. 2 Project No

21 COMMENT T-11 Health Canada considers PM 10 and PM 2.5 to be non-threshold substances, meaning that health effects may occur at any level of exposure. The International Agency on Cancer Research (IARC) has recently classified particulate matter as being carcinogenic to humans (Group 1). Health Canada considers that the risk associated with fine particles, particularly PM 2.5, is higher than the health risks associated with coarse PM or total suspended particulates (TSP, a measure of total suspended particulates, including liquid and solid particles, without particle size differentiation). Therefore, using 30 µg/m 3 as a daily threshold, as done in the assessment, to calculate the Acute Inhalation Risk Quotient does not measure the risk adequately. Revise the exposure assessment to include PM, PM 2.5 and PM 10 (non-carcinogenic) in order to more accurately predict potential health effects from this Project, or provide additional rationale as to why they have been excluded in the assessment. HHERA TSD, Section Canadian Malartic Corporation understands that Health Canada is concerned about the potential health effects of PM, PM 2.5 and PM 10. The classification of particulate matter as carcinogenic by the IARC occurred in October 2013, eight months after the Draft EIS/EA Report was published. The assessment was conducted using the accepted standards at that time. The screening threshold of 30 µg/m 3 set by the CCME and adopted by the MOE was used as the daily threshold as it was the relevant regulatory guidance at the time when the Human Health Assessment in support of the EA was being prepared. Although PM is now classified as a carcinogen, we are not aware of any regulatory agency that has developed an inhalation unit risk factor for PM 2.5, making evaluation of carcinogenic effects difficult. The only particulate species for which an inhalation unit risk factor has been developed is diesel particulate matter (DPM). DPM was evaluated in the EA as a carcinogen and it was concluded that while there are residual effects, they are of low significance.

22 COMMENT T-12 The results of the AERMOD modeling are presented in the TSD, however, no air plume dispersion isopleths are provided. It would be helpful for the reviewer in evaluating the potential for elevated air contaminant concentrations within the mine site, local, and regional study areas, including at locations of potentially sensitive human receptors, to see the plume dispersion isopleths. The isopleths for those substances evaluated in the human health risk assessment (HHRA), including NO 2, acrolein, PM 10, PM 2.5 and diesel particulate matter (DPM)) would be particularly useful. Provide the isopleths for the substances evaluated in the HHRA, and identify the locations of the nearest human receptors on the isopleths. Atmospheric Environment TSD Figures showing the isopleths for NO X, NO 2, Acrolein, PM 10, PM 2.5 and diesel particulate matter (DPM) which were evaluated in the HHRA are provided as Attachment 5 of the Final EIS/EA Report Addendum. Attachments Figures T-12-1 to T-12-5 in Attachment 5 of the Final EIS/EA Report Addendum

23 COMMENT T-13 According to Section , several receptors (PORs) were not considered as air quality receptors because property access is to be restricted by the proponent (PORs 10, 11, 17, 19, 23, 36 and 37). In Figure 3-5 (Human Health Risk Assessment Receptors), POR 23 is present on the map and appears to have been evaluated, and on Figure 4-1 (Noise Study Areas), an additional POR (POR 41) is identified near the tailings impoundment area but is not listed in Table 4-3 (Point of Reception Summary) for noise nor does it appear to have been evaluated in the air quality study. Indicate whether POR 23 was evaluated, and explain what POR 41 is and why it was not evaluated in either the air quality or noise study. Atmospheric Environment TSD. Some POR locations were removed from the Final EIS/EA Report as they are not considered points of reception in accordance with the Ontario Ministry of the Environment noise guideline NPC 300 and therefore do not require assessment in the Atmospheric TSD. Similarly, these sites no longer need to be identified in the HHERA TSD. This is a change that was made between the Draft and Final EIS/EA Report. Figure 3-5 of the Atmospheric Environment TSD has been updated in the Final EIS/EA Report identifying the PORs used in the assessment. Specifically: POR 23 is a Canoe Canada outfitters tourism establishment. Canadian Malartic Corporation has an agreement in place (the terms of which are confidential) with this establishment and access can be restricted; therefore it has not been considered a human health receptor in the Atmospheric TSD nor the HHERA TSD. POR 41 was the Accommodation Camp for the Project. It was not evaluated in either the air quality or the noise study because it is not a designated point of reception under NPC 300 as it is part of the actual Project. It should not have been included on Figure 4-1.

24 COMMENT T-14 Given that public access cannot be restricted (i.e. people can and likely will continue to use these sites) and several point of receptions were predicted to have elevated particulate matter and elevated noise levels, it is unclear why the proponent would remove the 20 PORs as they may represent worst-case exposure scenarios. Evaluate air quality and noise levels at these locations with respect to human health given that these may represent the worst-case exposure scenario. Atmospheric Environment TSD; Chapter 6, Section (same as T-21) The PORs were removed from the Final EIS/EA Report because they are not considered points of reception in accordance with the Ontario Ministry of the Environment noise guideline NPC-300 and therefore do not require assessment in the Atmospheric TSD. These sites were initially identified as potential points of reception in the Draft EIS/EA Report but were later screened out based on the definitions in NPC-300 for the Final EIS/EA Report. Similarly, these sites no longer need to be identified in the Human Health and Ecological Risk Assessment TSD. Figure 3-5 of the Atmospheric Environment TSD has been updated in the Final EIS/EA Report identifying the POR s used in the assessment. The HHERA evaluated the possible health effects to people who may occasionally access the area for recreational uses such as camping, fishing, hunting, and gathering within 10 km from the Mine Study Area. It was found that recreational use for short-term durations (few hours to a few weeks) does not pose a risk of any health concerns.

25 COMMENT T-15 Complete a worst-case scenario assessment during the construction phase. This scenario would include conducting an assessment for NOx, TSP, PM 10 and PM 2.5 (for 1-hr and 24-hr averaging period) and compared with Ontario Ambient Air Quality Criteria (AAQC) and /or National Ambient Air Quality Objectives (NAAQO). An assessment of this worst- case scenario for these parameters is important to ensure compliance is achieved and also to prove that the operation phase is the bounding case for this project. Provide a table with the modelling results for the construction phase air emissions since the releases of NOx and particulate matter (TSP, PM 10 & PM 2.5 ) are the main issues in the site preparation and construction phase and provide a worst-case scenario assessment during the construction phase. AETSD Report, Section pg. 19 Section , Table 3-1 pg. 15 AESTD Report, Version 2 response to IR EC-37 Compared to the Operations Phase, the Construction Phase will require much fewer trucks, as shown in the table below, resulting in lower fuel consumption and less dust generated. Parameter Construction Phase Operations Phase No. of trucks greater 2,000 HP Total distance travelled (VKT/day) (indicator for dust emissions) Diesel fuel consumption (L/yr) mobile sources (indicator for exhaust gases emissions) Diesel fuel consumption (L/yr) stationary sources (indicator for electricity exhaust gases emissions) 4,332 8,248 12,849,208 61,773,535 7,078,080 Emergency testing only Total diesel fuel consumption (L/yr) 19,927,288 61,773,535 There will also be a Best Management Practices Plan implemented through the Construction Phase. For this reason the Operations Phase was selected as the worst-case scenario for the Project. Further rationale for this selection is provided in Part B of Version 2 of the Atmospheric Environment TSD, Technical Memorandum Additional Environment Canada Comments on the Air Quality Assessment Approach. An assessment of the worst case Operations Scenario was completed.

26 Canadian Malartic Corporation has committed to air quality monitoring throughout the Construction and Operations Phase of the Project. A detailed air quality monitoring program will be submitted to the province for discussion prior to the start of the Construction Phase. This plan will consider the guidance outlined in the Ministry s Operations Manual for Air Quality Monitoring in Ontario. Canadian Malartic Corporation will work with regulators to determine reasonable parameters and frequency of sampling for monitoring during Operations and Construction Phases. 2 Project No

27 COMMENT T-16 Proponent is requested to confirm if background concentrations have been included in the modelling results (it appears they have not, from Table 3-19, pg. 43 of AESTD Report). Proponent is requested to revise Table 3-19 to include additional columns to show existing background for each substance, a column for predicted point of impingement (POI) concentrations for emissions from mobile sources and a column for total combined concentrations from background, predicted POI for stationary and mobile sources. Table 3-16 page 41 should be revised accordingly. The Proponent is requested to consider PM 10 and PM 2.5 contaminants of concern and that they are assessed and included in the table. It also requires combined predicted cumulative air quality concentrations during the various project phases with suitably conservative estimates of background concentration. The validity of an air quality assessment and conclusions about the significance of impacts (including cumulative effects) depend on a clear presentation of baseline data, inclusion of substances of concern and inclusion of all the relevant sources. As part of the cumulative effects assessment, the Proponent states that potential emissions from the Atikokan Generating station were considered and all of the emissions and sources of emissions were used as inputs to the AERMOD model (EIS Report, Version 2, page 6-223). A table should be provided indicating what emission rates were used as input to the model and identify the location of the emission sources, as the information was not found in the documents. Revise and finalize the air quality results table incorporating the changes listed in the previous column. The current tables do not contain all the information (e.g. background, mobile source emissions). Provide an emission rate and source table from Atikokan Generating Station that was used for dispersion modeling as part of the cumulative effects assessment. Confirm that air quality monitoring will be undertaken by the Proponent during all phases of the project to ensure that appropriate mitigation action is implemented to ensure that applicable guidelines are met. AESTD Report Section Air Quality Assessment EIS Report, Chapter 6, Pg (Atikokan Generating Station) Tables presented in response to comment MOE-Air 2 include baseline values, where available, as well as combined ambient air concentrations (baseline + maximum modelled Project predictions) in each of the air quality study areas. These values were compared to the applicable federal criteria. The maximum modelled

28 Project predictions include emissions from all significant sources, including mobile emissions. This data was passed on to be assessed in the Human Health and Ecological Risk Assessment (HHERA) and air quality was not identified as a significant risk at the human health receptors. At the time the Final EIS/EA was issued, the Atikokan Generating Station (AGS) was not operational and was not considered in the Cumulative Effects Assessment. The AGS is now operational as a biomass-fuelled plant. However, due to the distance between the AGS and the Project, there will likely be limited interaction between the AGS and the Project activities. As a precaution, air quality predictions were provided at the Town of Atikokan, which is further away from the Project than the AGS, and results showed that limited interaction or changes to air quality would occur at that location. Further detail is provided in Part B of V2 of the Atmospheric TSD. Again, this data was passed in to be assessed in the HHERA and air quality was not identified as a significant risk at any human health receptors. Canadian Malartic Corporation has committed to air quality monitoring throughout the Construction and Operations Phase of the Project. A detailed air quality monitoring program will be submitted to the province for discussion prior to the start of the Construction Phase. This plan will consider the guidance outlined in the Ministry s Operations Manual for Air Quality Monitoring in Ontario. Canadian Malartic Corporation will work with regulators to determine reasonable parameters and frequency of sampling for monitoring during Operations and Construction Phases. 2 Project No

29 COMMENT T-17 It is not clear whether the Proponent intends to conduct ambient air quality monitoring during the construction phase. An ambient air quality program should be conducted during both the construction and operation phases for this Project to verify the accuracy of the predictions related to the environmental effects on air quality. Follow-up monitoring will also assist in determining the effectiveness of mitigation and facilitate the development of adaptive management measures, should there be any unanticipated adverse environmental effects. It is not clear if the concentrations in Table 3-9 include emissions from mobile sources and background concentrations. These concentrations warrant the inclusion of NOx emissions in the ambient monitoring program. Undertake real time ambient air monitoring during site preparation, construction and operation phases for TSP, PM 10, PM 2.5 and NOx at a minimum. Given that mobile vehicle exhaust emissions represent a significant source of PM 10 and PM 2.5, and that HC considers that PM 10 and PM 2.5 have no threshold for adverse health effects, PM monitors could be used to track PM emissions which could then be compared with exhaust emissions calculated with the U.S. EPA MOBILE6 emissions model. Provide a framework for an ambient air monitoring program during construction which is to include the use of PM monitors and action levels that may trigger certain mitigations as part of the Follow-up Monitoring Program in consultation with relevant regulatory agencies including EC.. AESTD Report Section 7.0 Monitoring pg. 113 Section 3.4 Monitoring EIS Report Table 8-3 pg & 8-17 to IR HC-5 to IR HC-8 to IR HC-10 Table 3-9 illustrated the sources that were considered for the assessment that was carried out for Ontario permitting in accordance with MOE guidance, which does not require including mobile exhaust emissions. Modelling was completed for all emissions sources for the Project, including mobile exhaust emissions. Results of this modelling were passed on to be assessed in the HHERA and are also shown in the response to Comment MOE-Air 2. Canadian Malartic Corporation has committed to air quality monitoring throughout the Construction and Operations Phase of the Project. A detailed air quality monitoring program will be submitted to the province for discussion prior to the start of the Construction Phase. This plan will consider the guidance outlined in the Ministry s Operations Manual for Air Quality Monitoring in Ontario. Canadian Malartic Corporation will work with

30 regulators to determine reasonable parameters and frequency of sampling for monitoring during Operations and Construction Phases. 2 Project No

31 COMMENT T-18 The Proponent has provided some information but no details in terms of: objectives to be achieved through air quality mitigation measures; listing of methods to be applied and the conditions that trigger mitigation measures; frequency and record keeping to demonstrate adoption of actions; best management plan for fugitive dust; and planning measures aimed at reducing fuel and power consumption for the site. Confirm that the requirements of regulations and codes of practice stated in the previous column will be incorporated into the Best Management Plan (BMP) for dust, greenhouse gas (GHG) emission plan and other mitigation actions EIS Report, Chapter 8, Table 8-2 pg.8-11; AETSD Report, Section 3.3 and Table 3-20; pgs Canadian Malartic Corporation will prepare and implement a Best Management Practices Plan (BMPP) for Fugitive Dust as well as fulfill accounting and reporting requirements, if any, under provincial and federal GHG regulations. The preparation and submission of the Canadian Malartic Corporation BMPP to the MOE will likely be a condition on the Environmental Compliance Approval (ECA) required for the Project. Canadian Malartic Corporation s BMPP will be prepared in accordance with the MOE requirements and the conditions outlined in the ECA. All BMPPs typically include the following as a minimum: (1) identification of the main sources of fugitive dust emissions such as: (a) on-site traffic; (b) paved roads/areas; (c) unpaved roads/areas; (d) material stock piles; (e) loading/unloading areas and loading/unloading techniques; (f) material spills; (g) material conveyance systems; (h) exposed openings in process and storage buildings; and (i) general work areas. (2) potential causes for high dust emissions and opacity resulting from these sources;

32 (3) preventative and control measures in place or under development to minimize the likelihood of high dust emissions and opacity from the sources of fugitive dust emissions identified above. Details of the preventative and control measures shall include: (a) a description of the control equipment to be installed; (b) a description of the preventative procedures to be implemented; and/or (c) the frequency of occurrence of periodic preventative activities, including material application rates, as applicable. (4) an implementation schedule for the Best Management Practices Plan, including training of facility personnel; (5) inspection and maintenance procedures and monitoring initiatives to ensure effective implementation of the preventative and control measures; and (6) a list of all Ministry comments received, if any, on the development of the Best Management Practices Plan, and a description of how each Ministry comment was addressed in the Best Management Practices Plan. Canadian Malartic Corporation will also consider reporting under the following GHG programs, as applicable to the Project: - Ontario s GHG Emissions Reporting Regulation (O.Reg.452/09) - Government of Canada GHG Emissions Reporting Program (the GHGRP) - Carbon Disclosure Project 2 Project No

33 COMMENT T-19 All applicable adjustments that have been made to the measured/calculated Project-related operational noise levels in the derivation of the final percentage highly annoyed (%HA) for each impacted receptor need to be clarified through the rating levels used in calculating the %HA. Research indicates that certain sound characteristics can increase community annoyance (Canadian Standards Association or CSA, 2005). Note that a rating level is an adjustment applied to a measured or calculated sound level. Procedures on how to calculate %HA using a rating level with the applicable adjustments can be found in ISO (2003) or CSA (2005). Clarify if any sound adjustments (such as the day/night sound level adjustment or the impulsive/highly impulsive noise adjustment) were applied to predicted operational noise levels at any of the impacted receptors. HHERA TSD, Table 4-9 The predictions of percent highly annoyed (%HA) presented in the Atmospheric Environment Technical Support Document) (TSD) included an adjustment to the predicted Project noise levels of +10 db based on the noise receptors being located in a rural area. This is consistent with the ISO (CSA 2005) guideline. In addition to the +10 db adjustment for a quiet rural area, additional adjustments were included where appropriate for specific sources. For example, for simplification and conservatism, a +5 db adjustment was applied to noise sources that were considered tonal. However, as the resulting noise levels at the receptor locations are not predicted to be tonal, the addition of the 5 db adjustment was not required as specified in Appendix A of CSA (2005), Adjustments for tonal character should only be applied when the total sound is audibly tonal at the receiver location. Therefore, the predictions of %HA are likely conservative. No other adjustments were warranted as the sources are not expected to be impulsive, highly impulsive or high energy impulsive. Also, as noted in CSA 2005, a 0 db adjustment is recommended for industrial sources. The sources of sound involved during operations of the Project would be road traffic and industrial type sources. If more than one adjustment applies for a source of noise, CSA 2005 states that only the largest adjustment shall be applied. Therefore, no other adjustments were made.

34 COMMENT T-20 The HHERA noted correctly that there is a possibility for Project noise-related sleep disturbance. However, further discussion on mitigation measures (i.e. complaint resolution mechanism) was not described in the assessment. Explain how community noise complaints related to sleep disturbance from Project noise may be mitigated or addressed. HHERA TSD, Section 4.5 As the Project meets MOE noise guidelines at the plane of window (i.e., outdoors), the indoor noise level is expected to be db lower and sleep disturbance would not be anticipated. If noise levels exceed MOE guidelines, mitigation measures such as equipment mufflers or enclosures will be put in place to ensure compliance with NPC 300.

35 COMMENT T-21 It is unclear from the discussion of designated camp sites whether these sites are intended for people who camp (i.e. tent) or whether there are more permanent structures in place. In the event that these sites are used for tent camping, it is expected that noise levels experienced indoors would be higher than in permanent structures with doors/windows/insulation. Predicted noise levels at these receptors should therefore assume limited to no attenuation between indoors and outdoors. Many noise guidelines are based on acceptable noise levels at the exterior of a building (assuming a noise level reduction of db between indoors and outdoors), thus, these noise guideline levels may not be appropriate for tents. Provide a discussion about the expected users of the designated camp sites. If tent camping is likely, provide a discussion about expected indoor noise levels (assuming limited/no attenuation between indoors and outdoors), whether these levels may result in increased annoyance, and whether or not provincial noise guidelines are applicable for these receptors. Atmospheric Environment TSD (same as T-14) Designated campsite PORs were removed from the Final EIS/EA Report as they are not considered points of reception in accordance with the Ontario Ministry of the Environment noise guideline NPC-300 and therefore do not require assessment in the Atmospheric TSD. The location and nature of these sites are undetermined and are not associated with any permanent structures, camping fees or services. These sites were initially identified as potential points of reception in the Draft EIS/EA Report but were later screened out based on the definitions in NPC-300 for the Final EIS/EA Report. Similarly, these sites no longer need to be identified in the Human Health and Ecological Risk Assessment TSD. Figure 3-5 of the Atmospheric Environment TSD has been updated in the Final EIS/EA Report identifying the POR s used in the assessment. The HHERA evaluated the possible health effects to people who may occasionally access the area for recreational uses such as camping, fishing, hunting, and gathering within 10 km from the Mine Study Area. It was found that recreational use for short-term durations (few hours to a few weeks) does not pose a risk of any health concerns.

36 COMMENT T-22 As part of the initial sampling parameters presented in Section (Laboratory Analysis) of the Water and Sediment Quality Technical Supporting Document (TSD), microorganisms (including e-coli and total coliforms) were analysed in baseline surface water samples. The sampling was discontinued because of the consistently non-detectable concentrations. Given that treated sewage from the worker camp is expected to be discharged to surface water that is also to be used as the freshwater intake for the camp and process plant (Sawbill Bay), it would be useful to monitor the water quality for microorganisms (such as total and fecal coliforms). Should the potable water supply be taken from the same receiving water body as the sewage treatment plant, provide a framework for a monitoring plan that includes monitoring for microorganisms. This would form part of the Follow-up Monitoring program. Water and Sediment Quality TSD, Section 2.2.3; Chapter 8, Section Monitoring of potable water sources for microorganisms will be included in the detailed monitoring program for the Project.

37 COMMENT T-23 The report does not identify any monitoring of country foods during operations. Given that country foods were evaluated for baseline conditions, in the event of public complaints about changes in taste, quality or other aspect related to country foods, additional sampling could be undertaken. Provide confirmation on whether a country foods sampling program will be included in the follow-up monitoring program or provide rationale as to why they have been excluded from the environmental management plan. HHERA TSD, Section 6.0 IR to HC-4 Canadian Malartic Corporation understands that the Government Review Team is concerned about potential changes to country foods resulting from the Project. As discussed in the response to Health Canada s comment HC-4, included as part of the Final EIS/EA Report, modelling of maximum deposition rates from the Project during operations suggests that negligible increases in vegetation concentrations (i.e., <0.3%) would occur as a result of the Project. Thus, monitoring of country foods is not recommended. There may be natural variation in chemical concentrations in country foods that are un-related to the Project, making the interpretation of any monitoring data that would be collected during Project operations difficult. Canadian Malartic Corporation is committed to working with local land users and Aboriginal communities. This commitment includes the use of committees to identify social and cultural concerns as well as ongoing support for cultural events and initiatives. Should changes in country foods be identified through these committees, further monitoring and mitigation measures will be implemented.

38 COMMENT T-24 Table 6-56 of the EIS under the activities of Development of the Open Pits and Operation of Processing Plant the column entitled Residual Environmental Effect it is stated that there are predicted risks to some human receptors close to site and then in the Significance of Residual Effect column it is stated Low: no impacts predicted for human health and ecological receptors. Given that some risks were predicted for human receptors close to the site, it is unclear how the conclusion would be that there were no impacts predicted for human receptors. For these two activities, explain how the conclusion was reached that there would be no impacts predicted for human receptors given that some predicted risks were identified. Chapter 6, Table 6-56 While residual effects were identified for human health receptors close to the Site, based on considerations of extent, duration, frequency, reversibility and magnitude, the significance of the residual effects is considered to be low. The statement under Significance of Residual Effect is incorrect and should not state Low: no impacts predicted. The correct conclusion is that the effects are not expected to be significant: Low: predicted effects on human health or ecological receptors are not expected to be significant.

39 COMMENT T-25 The EIS contains insufficient information regarding the use of waterbodies affected by the project. information on the use of those waterbodies was found in Section or in Table No Based on Transport Canada s current approach to assessing navigability for the purposes of the Navigable Waters Protection Act (NWPA), which is soon to be replaced by the Navigation Protection Act (NPA), the waterbodies at the Project site that are potentially navigable are Mitta Lake and API#2. Information on the use of Mitta Lake and API #2 is required in order to assess the navigability of these waterbodies, provide comment on the significance of impacts to navigation and determine whether an Order in Council under the NWPA/NPA is required. Provide information on current and/or historic use of Mitta Lake and API #2. EIS Section Canadian Malartic Corporation has been in contact with Transport Canada throughout the Project planning process and would like to further discuss the potential that the Project could require an Order in Council for the loss of potentially navigable waters. Canadian Malartic Corporation has shared our knowledge of the current and/or historic use of Mitta Lake and API#2 with Transport Canada. The details of which are restricted to the granting of bait fishing licenses in the area that these waterbodies are located. Canadian Malartic Corporation does not believe that an Order in Council will be required for the Project, but looks forward to working further with Transport Canada to clarify this issue. Information on the current and/or historic use and the accessibility of Mitta Lake and API #2 will be included in the work permit applications required under the applicable legislation in place at the time of submittal (e.g., Request for Work Approval under the NWPA).

40 COMMENT T-26 The Executive Summary states that only two lakes will be eliminated (Mitta Lake and API 2), while on page 6-43 it states that 4 lakes will be lost (Mitta Lake, API 2, API 11, and API 13). Provide clarification on the number of lakes that will be eliminated. ES-8, 6-43 The Executive Summary highlights the two small lakes that would be eliminated by the Open Pit and the Tailings Management Facility. The Executive Summary also summarizes the aquatic biology habitat losses as including 0.8 ha of Sawbill Bay, 4 ha of inlet streams, 0.5 ha of baitfish ponds in the lower reaches, 1.8 ha of headwater streams, 30 ha of lakes and 3.7 ha of baitfish and northern pike ponds in the headwaters. The 30 ha of lakes described in this list of direct aquatic habitat impacts includes the loss of 4 lakes: Mitta Lake, API 2, API 11, and API 13. Mitta Lake is located within the planned Open Pit, API 2 is located within the planned Tailings Management Facility, API 11 is located within the planned Waste Rock Stockpile and API 13 is located within the planned Emergency Spill Pond. All of these habitat losses will be offset by compensation projects outlined in the No-Net Loss Plan (NNLP) prepared for the Project, and as a result, there will be no residual effects from these losses. A complete summary of lakes that will be directly affected by the Project is provided in Table 3-5 of the Aquatic TSD.

41 COMMENT T-27 Results of the short term (shake flask) leaching tests of the waste rock samples indicate that there is selenium metal leaching potential for the waste rocks. The upper ranges of selenium leachate concentrations are 6-16 times higher than the CCME guideline (1 ug/l). Given the sensitivities concerning the impacts of selenium on confined water bodies (e.g., lakes and ponds), it is necessary that the Proponent take appropriate steps to manage the effluent from waste rock stockpiles to prevent any potential impacts to the adjacent waterbodies (e.g., Sawbill Bay, Lynxhead Bay and Trap Bay). In the Aging Test results-tailings Process Water (Table 3-12 of the TSD Hammond Reef Gold Project Geochemistry, Geology and Soils), the Proponent has not presented the data for selenium. Explain how the proponent plans to address/ mitigate the potential impacts of selenium metal leaching from waste rock to the adjacent water bodies by means of surface and subsurface effluent discharge (particularly seepage). Provide the aging test results for selenium. Hammond Reef Gold Project Geochemistry, Geology and Soils TSD Section (Short-Term Leach Testing and Net Acid Generation Leach Test) Hammond Reef Gold Project Geochemistry, Geology and Soils TSD Section (Short-Term Leach Testing and Net Acid Generation Leach Test) Age test results for selenium are provided in Appendix 2.III B-6 and indicate that all concentrations are at or below detection limits. Short term leach tests results are provided in Appendix 2.III B-4. Of the 41 samples analyzed only 3 samples contained concentrations above the detection limit of 1 ug/l, two samples contained values near the quantitation limit of the analyses 3 ug/l and only one sample, from a minor unit (Quartz Vein) had a concentration of 16 ug/l. When evaluating overall leachate potential of the mine rock each of these samples was considered and used to develop an overall leachate concentration for the pile based on consideration of all of the results and the proportion of the rock that the single elevated sample represents (see Site Water Quality TSD). Although CCME or receiving water guidelines are not directly applicable to short term leach test results, comparisons are provided for reference to identify parameters that need to be carried forward and evaluated with respect to overall site water quality (see Site Water Quality TSD and Lake Water Quality TSD), such as was conducted for this Project. Since these few samples represent only a small fraction of the rock, when results are considered and carried forward into the overall site water quality model there are no predicted adverse impacts to aquatic life.

42 COMMENT T-28 The Proponent has used the geochemical test results in their water quality predictions. For example, they used the tailings process water quality from the aging testing in the water quality model. In Table 3-12, there are several parameters (e.g., Al, Cd, Co, Cu, Mo, Ni, Pb, U and Zn) whose total concentrations exceed one or more of the applicable criteria (PWQO, MISA or CCME). However, for the dissolved concentrations for these parameters, which are relatively lower than the total concentrations, no such exceedances are reported. It was noted that the Proponent has used the dissolved concentrations for some parameters, which are one order of magnitude lower than the total concentrations as the input source term data in the water quality modelling. The results do not accurately reflect the water quality predictions for the effects assessment. Provide an updated water quality assessment that incorporates total concentrations into surface water quality modelling. Hammond Reef Gold Project Geochemistry, Geology and Soils TSD Section Aging Tests, page 61. Total concentrations are included in the water quality model for the basin as provided in Section of the Lake Water Quality TSD. The predicted total concentrations presented in Table 4-8 consider the removal of Total Suspended Sediment (TSS) to a discharge concentration of g/l based on a maximum permitted MISA TSS discharge of g/l (O.Reg. 560/94), and potential for air deposition from site based on air deposition modelling results. The inclusion of TSS from the site waters and from air deposition does not materially change the results of the model or interpretation of model results as demonstrated in Table 4.8 of the Lake Water Quality TSD.

43 COMMENT T-29 In Table 4-7 of the Hammond Reef Gold Project Site Water Quality TSD, the Proponent has provided the proportions of different rock units (expressed as a fraction) that are encountered in the Project area. This information is also presented in the Hammond Reef Gold Project Geochemistry, Geology and Soils TSD version 2 (page 2/13), where the Proponent has reported the distribution of various rock units in percentage. It appears that the proportions of various rock units as reported in different TSDs are not consistent. For example, in the Hammond Reef Gold Project Site Water Quality TSD, the proportion of tonalite is reported as 0.49 whereas in the Hammond Reef Gold Project Geochemistry, Geology and Soils TSD version 2, it is reported as 24% for waste rock. Clarify the proportions of various rock units. Explain why the tailings sample has a different composition than the composition of the deposit. Hammond Reef Gold Project Geochemistry, Geology and Soils TSD Hammond Reef Gold Project Site Water Quality TSD The characterization of rock units within the deposit has shown some variability at this stage of the planning process. This inconsistency was identified and discussed in detail in IR MOE-NR-GW-02, and the Geochemical Sample Representation Letter found in the Supplemental Information Package of the Version 2 Geochemistry Geology and Soils TSD. After receiving additional comments on the Final EIS/EA Report, Canadian Malartic Corporation hosted a workshop on June 2, 2014 with the Government Review Team to further discuss and explain water quality modelling methods and predictions. This workshop included detailed explanation of geochemical influence on water quality. Further detail explaining the similarity of the geochemistry of the rock types and tailings is also provided in a memorandum entitled Water Quality Background Information, provided as Attachment 4 of the Final EIS/EA Report Addendum. Early stage geologic information is developed through various sources, including government records (e.g. OGS open file reports) and various exploration programs by private companies. Several rock types may be similar in nature, and vary only slightly in visual properties or chemical properties, as such different geologists may label these units differently. As the Project develops to a block modelling stage, the units often get further simplified based on key properties to allow for appropriate model development. The production of tailings samples from metallurgical testing used all available information to develop appropriate samples which were used to test recovery methods for the expected ore. The tailings products from

44 the metallurgical testing were relatively large samples (on the order of 10s to 100s of kg) and are the most representative materials with respect to tailings characteristics that are possible to produce, short of operational tailings production. The geochemical characterization work, by necessity, takes place early in the mine planning process, resulting in some variability. The representativeness of sampling for tailings is described in IR MOE-NR-GW-02 which was provided in Appendix 1.IV of the Final EIS/EA Report in response to comments on the Draft EIS/EA Report. Based on the information available on tailings, and waste rock sample rock types that make up those tailings, it is considered that the tailings samples produced are reasonable. The results of testing of these samples are appropriately conservative with respect to water quality predictions for the site. 2 Project No

45 COMMENT T-30 The water quality modelling predictions for the TMF are based on geochemical testing of a single tailings sample (size of sample unknown) that may not be representative of the proportions of rock types that comprise the orebody. Based on Table 1 of the Nov 21, 2013 memorandum in the Hammond Reef Gold project Geochemistry, Geology and Soils TSD version 2, it appears that no tailings composite samples were collected from major felsic rock units represented by fine grained granite and chloritic granite porphyry. The fine grained granite represents about 16% of the mineralized deposits, while the chloritic granite porphyry represents 8-13% of the mineralized deposits. Furthermore, Table 3-5 of the Hammond Reef Gold project Geochemistry, Geology and Soils TSD version indicates that the fine grained granite has one of the highest detectable maximum selenium concentrations (0.8 ug/g) among all rock types. This rock unit also has the maximum concentration of cadmium (0.47 ug/g) and chromium (0.27% as Cr2O3 equivalent). EC notes that there is quite a bit of variability in the concentrations of sulfide-sulfur ( wt % S) and carbonates (2.6-20% CO2) among the metallurgical samples in the data presented in Table 4. The Proponent is requested to test additional samples of tailings in order to develop a more reliable characterization of the geochemical behavior of tailings, and thereby develop a more reliable characterization of predicted water quality. Please respond to questions related to the single tailings sample that was previously tested: 1) What was the size of the original tailings sample, and the size of the samples that underwent geochemical testing? 2) How do the composite tailings sample rock proportions compare to the proportions of rock types in the ore that is to be milled? 3) Were all ten variable metallurgical samples subjected to whole rock elemental analysis? Hammond Reef Gold Project Geochemistry, Geology and Soils TSD, Section Hammond Reef Gold project Geochemistry, Geology and Soils TSD version 2 Nov 21, 2013 memorandum, figure 1, Table 1

46 Canadian Malartic Corporation understands that the Government Review Team is concerned about the representativeness of the tailings sample used in the geochemistry and water quality predictions provided in the Final EIS/EA Report. This concern was addressed following submission of the Draft EIS/EA Report as provided in response to Information Request EC-21 and MOE-NR-GW-02 as presented in Appendix 1.IV of the Final EIS/EA Report. After receiving additional comments on this topic, Canadian Malartic Corporation also held a workshop in June 2014 with government regulators to further discuss and explain specific methods and assumptions, including tailings predictions. To summarize, the following is provided in answer to your questions: 1) The size of the samples that underwent geochemical testing are about 1 to 5 kg, however these were split from samples that were from 10 to 100 kg in size and used to produce the metallurgical samples. 2) The composite tailings sample rock proportions are similar to the proportions of rock types in the ore that is to be milled, as shown in the memorandum entitled Water Quality Background Information in this supplemental to the Final EIS/EA Report. 3) Metallurgical composite samples were subjected to whole rock and trace metal elemental analysis which is provided in the memorandum entitled Water Quality Background Information in this supplemental to the Final EIS/EA Report. The tailings sample was generated from a set of ten variable Metallurgical (Met) samples each of which was tested individually, the results of which are provided in the Supplemental Information Package of the Geochemistry, Geology and Soil TSD. The ABA results show that regardless of the location within the deposit, the sulphide-sulphur contents of the samples were generally low, ranging from 0.09 to 0.35 wt% as S. The CaNPR values ranged from 5.8 to 62 t CaCO3/1,000 t. Each of the individual samples, as well as the composite sample, are classified as non-acid generating with excess neutralization potential according to the MEND (2009) and AMIRA (2002) guidelines. It should be noted that at this stage of the Project there is very little actual tailings available for testing. As stated in MEND (2009), Section 8.2 Prior to mining, the choice of material to sample is often restricted to drill core and to metallurgical testing for tailings ; and, Limitations in the availability and accessibility of materials to be sampled need to be considered in the design of a sampling program. With respect to metal leaching potential it should be noted that Tailings are composed of the rock types described in the Geochemistry, Geology and Soils TSD as further discussed in a letter to Canadian Malartic Corporation in response to MOE-NR-GW-02, which can be found in the Supplemental Information package of the Geochemistry, Geology and Soil TSD. Only gold is removed in the process, thus the tailings and rock are essentially the same. For all rock types expected to be encountered in the tailings ample information is provided with respect to that as indicated in the EIS Guideline in Section and in Section Geology and Geochemistry. The leachate concentrations determined for tailings are based on a composite sample which considers the latest process design as available at the time of sampling and testing. The leachate concentrations are generally consistent with those of the waste rock, as would be expected for a deposit of this type. Due to material availability limitations, additional testing of tailings cannot be undertaken until processing of ore is underway, at which point confirmation samples will be collected, however the overall facility is designed to be sufficiently robust such that a seepage collection system is included in the design, and is available to direct seepage to treatment if necessary. 2 Project No

47 Based on the entirety of the information available on tailings, and waste rock sample rock types that make up tailings, it is considered that the tailings samples produced are reasonable for the purpose of the Final EIS/EA report, and that the results of testing of these samples are appropriately conservative with respect to water quality predictions for the site (as discussed in our meeting of June 4, 2014, and as described in the Site Water Quality TSD; Geochemistry, Geology, and Soils TSD). Further detail showing the similarity of the geochemistry of the rock types and tailings is provided in the memorandum entitled Water Quality Background Information, provided as Attachment 4 of the Final EIS/EA Report Addendum. 3 Project No

48 COMMENT T-31 It is understood that some overburden will be used at the project site for closure and reclamation purposes. It is noted in the Geochemistry, Geology and Soils TSD that the Proponent s geochemical characterization of the overburden materials is not based on the testing of the overburden materials that occur directly over the pit, but rather based on the overburden that occurs in the nearby aggregate sources. The metal leaching potential for the overburden materials from potential aggregate sources further away from the open pit may be lower than that for the overburden occurring over the open pit area. On this basis, it appears that the characterization of metal leaching potential of the overburden materials may not be representative of the overburden directly over the open pit. The short-term leach tests indicate that Ag, Al, B, Co, Cr, Cu, Fe, Pb, V and Zn concentrations exceeded the corresponding PWQOs for one or more overburden samples. Out of them Al and Fe concentrations in the leachate of some samples exceeded the corresponding PWQOs by more than 10 times. Overburden from the pit area may exhibit even higher values. The Proponent s statement that the overburden is expected to be of low metal leaching potential is not well supported. There is concern that the water quality predictions for the overburden materials may have been underestimated. This information is important for understanding the water quality predictions for the overburden material. Clarify whether the geochemical data for the overburden from potential aggregate sources were used as source term input in the water quality modeling. Given the metal leaching potential for a fairly large number of parameters, undertake geochemical testing on overburden samples collected from the pit area. The data should be compared to the other overburden samples that were previously tested, and if warranted on the basis of significant differences, the water quality modeling should be revised. Hammond Reef Gold Project Geochemistry, Geology and Soils TSD, version 2, page 8/8 to IR# EC-29 Canadian Malartic Corporation understands that the Government Review Team is concerned about the robustness of the geochemistry data for the overburden at site. Geochemical evaluation of overburden is discussed in response to Information Request EC-29, as provided in Appendix 1.IV of the Final EIS/EA Report. Overburden units are described in Section 4.0 (Soils) of the Geochemistry Geology and Soils TSD. Water quality model inputs are based primarily on the geochemistry of potential disturbed rock from the pit rather than

49 overburden. Natural runoff water quality is used to represent overburden runoff, as the overburden is expected to be similar to the upper layer of naturally occurring material in the LSA. Given the glacial history of the region the discontinuous, overburden will be similar to surface soils, as such the chemistry result presented in Table 4-5 of the Geochemistry, Geology and Soils TSD are considered reasonable and valid for evaluation of overburden chemistry characteristics. Test results from these materials show consistent, low solid phase metal concentrations over the local study area. Additional testing of overburden will be undertaken prior to construction or operations, as part of detailed design planning and/or regular operational monitoring. Sampling of overburden in the vicinity of the pit will be included in the Geochemical Characterization Plan for the site to be undertaken during operations. Geochemical confirmation assessment of overburden will be conducted prior to use for site construction. The conceptual current mine design is robust in that seepage from the overburden stockpile is currently captured and can be treated (as an additional mitigation strategy) if necessary prior to discharge from the site. 2 Project No

50 COMMENT T-32 This section deals with the summary and conclusions of the geochemical testing for tailings samples. The Proponent states that Other metals reporting sporadic concentrations greater than the comparison guideline values in waste rock leach testing include cadmium, silver, chromium, zinc and iron. It is not clear why the Proponent is talking about the comparison guideline values in waste rock leach testing for metals in tailings samples. The mention of comparison guideline values for waste rock leach testing above does not seem appropriate for the tailings. Clarify why Osisko [Canadian Malartic Corporation] used the comparison guideline values in waste rock leach testing for tailings samples. This needs to be clarified to ensure that the conclusions of the geochemical testing for tailings samples are sound. Hammond Reef Gold Project Geochemistry, Geology and Soils Technical Support Document (TSD) Section Tailings of the Geochemistry, Geology and Soil TSD, Version 1 In response to comments received on the Final EIS/EA Report, Canadian Malartic Corporation held a Geochemistry and Water Quality workshop on June 4, 2014, with the Government Review Team. This workshop focussed on water quality modelling methods and assumptions, and worked through detailed examples to fully explain modelling rationale. A Technical Memorandum was also produced to provide further detail showing the similarity of the geochemistry of the rock types and tailings, which allows a better understanding of the context of the overall results. This information was circulated to the Government Review Team and is provided in a memorandum entitled Water Quality Background Information, provided as Attachment 4 of the Final EIS/EA Report Addendum. The tailings are comprised of the various rock types within the deposit. By necessity, the amount of tailings produced during the exploration phase and feasibility stages of a project is limited, therefore a comparison to the values from the various rock types included in the waste rock samples provides context with respect to how consistent the tailings leachate values are relative to those of the waste rock, which allows for a better understanding of the characteristics of the data-set, deposit and tailings as a whole.

51 COMMENT T-33 The short term leach testing and NAG leach test results indicate that the tailings from the Hammond Reef project have metal leaching potential with respect to aluminum, copper, silver, boron, and zinc. For example, the short term leach testing results for tailings indicate that Al concentrations were greater than the CCME aquatic and PWQO guidelines and the NAG leach test results indicate that ph values (in excess of 11) were greater than all applicable criteria. Yet, in the EIS, the Proponent has stated in several instances that there is no metal leaching potential from the tailings. The statement in the Public Communications Tracking Log in Appendix 7.III made by the Proponent that Geochemical testing has shown that there is no potential for acid rock drainage or metal leaching may be true for ARD, but it does not appear to be true for metal leaching.. Using an errata table, indicate all references in the EIS where it states that there is no metal leaching potential in tailings since the geochemical leaching test results for tailings indicate that several parameters will be exceeding the applicable guidelines. Hammond Reef Gold Project Geochemistry, Geology and Soils TSD Section Short-Term Leach Testing Appendix 7.III (Public Communications Tracking Log) We have not found any instances in the Final EIS\EA report text or TSD reports where it is stated that there will be no metal leaching, it is understood that metal will leach from any materials, be they from a mine, soil, or roadway. The leaching potential of the mine rock and tailings is assessed, and the values used in the impact assessment as defined and developed through the Geochemistry Geology and Soils TSD; Site Water Quality TSD; and Aquatic Environment TSD and Human Health and Ecological Risk Assessment TSD. It is noted in the public communications tracking log in two instances (Appendix 7.III, Page 23 and Page 36) where the presenter did state no metal leaching and it is considered that this was a result of a non-technical paraphrasing of the technical information and that the intent was to state that there would be no adverse effects as a result of metal leaching. It should be noted that it is stated in the document there will be no adverse effects as a result of metal leaching. This statement is based on the results of the overall impact assessment, and include consideration of all factors as described in Geochemistry Geology and Soils TSD; Site Water Quality TSD; and Aquatic Environment TSD and Human Health and Ecological Risk Assessment TSD. Of note is that it is clearly stated in the executive summary of the Final EIS/EA Report, under the Geology, Geochemistry and Soils section Relative to comparison criteria, waste rock and tailings samples leachate

52 concentrations were slightly elevated for aluminum with sporadic concentrations of other metals such as arsenic, copper cadmium, iron, selenium, vanadium and zinc slightly greater than the comparison criteria. Where these sample values are above the comparison criteria, additional water quality evaluation within an overall site wide context has been conducted as described in the site water quality evaluation. 2 Project No

53 COMMENT T-34 The net acid generation (NAG) leach testing results of waste rock samples indicate that Al, Cr, B, Se, V, As and Cu concentrations exceeded one or more of the applicable guidelines (e.g., PWQO and CCME). The above results indicate that the waste rock collected from the Hammond Reef deposit have metal leaching potential with respect to the above-noted parameters. The statement in the Public Communications Tracking Log in Appendix 7.III made by the Proponent that Geochemical testing has shown that there is no potential for acid rock drainage or metal leaching may be true for ARD, but it does not appear to be true for metal leaching. Using an errata table, indicate all references in the EIS where it states that there is no metal leaching potential in waste rock since the geochemical leaching test results for waste rock indicates that several parameters will be exceeding the applicable guidelines. Hammond Reef Gold Project Geochemistry, Geology and Soils TSD Section Short-Term Leach Testing Appendix 7.III (Public Communications Tracking Log) We have not found any instances in the Final EIS\EA Report text or TSD reports where it is stated that there will be no metal leaching, it is understood that metal will leach from any materials, be they from a mine, soil, or roadway. The leaching potential of the mine rock and tailings is assessed, and the values used in the impact assessment as defined and developed through the Geochemistry Geology and Soils TSD; Site Water Quality TSD; and Aquatic Environment TSD and Human Health and Ecological Risk Assessment TSD. It is noted in the public communications tracking log in two instances (Appendix 7.III, Page 23 and Page 36) where the presenter did state no metal leaching and it is considered that this was a result of a non-technical paraphrasing of the technical information and that the intent was to state that there would be no adverse effects as a result of metal leaching. It should be noted that it is stated in the document there will be no adverse effects as a result of metal leaching. This statement is based on the results of the overall impact assessment, and include consideration of all factors as described in Geochemistry Geology and Soils TSD; Site Water Quality TSD; and Aquatic Environment TSD and Human Health and Ecological Risk Assessment TSD. Of note is that it is clearly stated in the executive summary of the Final EIS/EA Report, under the Geology, Geochemistry and Soils section Relative to comparison criteria, waste rock and tailings samples leachate concentrations were slightly elevated for aluminum with sporadic concentrations of other metals such as arsenic, copper cadmium, iron, selenium, vanadium and zinc slightly greater than the comparison criteria. Where these

54 sample values are above the comparison criteria, additional water quality evaluation within an overall site wide context has been conducted as described in the site water quality evaluation. 2 Project No

55 COMMENT T-35 The Proponent states: The ore stockpiles will be protected with ditching to control runoff (S 5.1.2). Low-Grade Ore Stockpile: Runoff from the stockpile will be collected in a perimeter ditch system, with all collected flows pumped to the PPCP (S ). Overburden Stockpile: Runoff from the stockpile will be collected in perimeter ditch system, with the collected water pumped to the PPCP for use as re-claim in the plant or treatment and discharge (S.5.2.3). Describe the proposed mitigation measures to limit, prevent, and collect seepage from the TMF, WRMA, ore, low-grade ore, and overburden stockpiles. Also, clarify whether all ditches will be dug to the overburdenbedrock interface, and if not, how the Proponent proposes to collect seepage in those situations. EIS Guidelines S 13 Environmental Management S 13.1 Planning Measures to limit, prevent and collect seepage from the TMF, WRMF, ore, low-grade ore, and overburden stockpiles have been developed at the conceptual level at this time and consist of a series of collection ditches, and pumping stations. There are many additional options to intercept seepage from these facilities. During the detailed design stage for the Project additional drilling will be undertaken along the dam alignments, ditch alignments and near the edges of proposed stockpiles, and at that time it will be appropriate to further specify the details of the seepage collection system design. Considerations during detailed design will include bedrock and depth of overburden conditions, and the use of pumping as required to meet appropriate design objectives.

56 COMMENT T-36 The Proponent states For seepage from the TMF natural degradation of cyanide is expected to occur as the water migrates from the TMF to the nearest receiver (Lizard Lake). Explain why only Lizard Lake is identified as being impacted by seepage from the Tailings Management Facility. There are other water bodies in the immediate area including API 37, API 47, API 48, API 2, API 8, as well as the wetlands and lake south of API 7 and north of API 43 that drains into Lizard Lake which could potentially be affected by seepage. Hammond Reef Gold Project Site Water Quality TSD S Material Usage. The TMF conceptual design takes advantage of high ground and bedrock around much of the perimeter which minimizes construction costs. The selection of Lizard Lake as the potential receiver for seepage was based on a review of existing mapping of site topography, catchment areas as provided in the Hydrology TSD, Figure TC-7 (Site Watersheds), and bedrock outcrops as identified during site visits. Based on this review, primary drainage pathways were identified as occuring towards Lizard Lake to the east, and Marmion Basin to the southwest. Other nearby waterbodies are primarily located outside of the TMF watershed and are bounded by high ground, which consists of substantial bedrock outcrop. There is only one location (AP#8) which is within the upstream catchment of Lizard Lake, however it is considered that, given its location, there would be little potential for seepage, and that assessment of Lizard Lake is appropriately conservative for evaluation potential for impact on the east side of the TMF, prior to all waters discharging to Marmion Basin. All waters, including those from Lizard Lake and upstream locations are already considered within the total discharge applied to Marmion Basin. Concentrations for each potential point source were considered as described in IR-MOE-NR-GW-16 located in Appendix 1.IV of the Final EIS/EA Report. The direct discharge of these concentrations into a water body is not expected to have negative aquatic impacts. Additional drilling, modeling and monitoring will be completed during the design and operational phases. Additional mitigation of seepage to smaller water bodies if necessary will be determined during the detailed design phase. Options for additional mitigation measures include additional ditching or pumping back of water to the TMF.

57 COMMENT T-37 In the Site Water Quality TSD, the Proponent provides a value for Evaporation, seepage & spillage losses denoted as E&S in Figure 3.3 as 0.08 m 3 /hour equally for the waste rock, overburden and ore. It is assumed in this case the ore to represent low-grade ore stockpile. In Appendix 3.II Site Wide Water Balance, the rates of seepage losses for all of the mine components modeled in the water balance are all given as zero (0). The combined rate for evaporation, seepage and spillage of 0.08 m 3 /hour, which represents 1.9 m 3 /d, does not seem plausible and the assignment of zero (0) seepage losses in the water balance model is questionable. The footprints (surface area) and volumes for the stockpiles of waste rock, overburden and low-grade ore are all different and hence the assigned singular value does not seem appropriate. Moreover, the 1.9 m 3 /d in Figure 3-3 is not consistent with the zero (0) value given in the water balance. Provide an explanation and rationale for the values of 1.9 m 3 /d for E&S as well as for the zero (0) value. It is recommended that a sensitivity analysis be conducted on the quantity and quality of seepage as it relates to the predictions of water quality for the site and ultimately for the receiver. This information is necessary to have a clear understanding of water quality effects from the Project. Hammond Reef Gold Project Site Water Quality TSD Figure 3-3: String Diagram Ultimate Mine Configuration Appendix 3.II Site Wide Water Balance In Figure 3.3, the Evaporation, seepage and spillage losses are from the ponds located at the water collection pumping stations. Seepage rates from all facilities will be controlled and is assumed to be zero, as noted in Section of the Site Water Quality TSD. Spillage losses are also assumed to be negligible. Therefore, with the exception of the Plant Site, the Evaporation, seepage and spillage losses shown on Figure 3.3 are comprised only of evaporation from pumping station ponds. Each pumping station pond is assumed to have the same surface area and the WRMF, overburden stockpile and low-grade ore stockpile each have 3 pumping station ponds in their denoted watershed areas. Therefore the evaporation losses from the WRMF, overburden stockpile and low-grade ore stockpile watersheds are equal and are estimated to be 0.08 m 3 /hr. The values presented in Figure 3.3 are consistent with the evaporation estimates in the Appendix 3.II Site Wide Water Balance. Evaporation and losses to groundwater from the surfaces of the WRMF, overburden stockpile and low-grade ore stockpile are implicitly accounted for in the assigned runoff coefficients for each area. For these facilities, 15 % of precipitation is assumed to be lost to the system due to evaporation, reduction in snow accumulation due to the height of the piles and/or losses to the groundwater system. As discussed during the April 28, 2014 water

58 quality workshop with the Government Review Team, this is considered a reasonable and conservative assumption for the purpose of evaluating water quality impacts given that: All runoff concentrations from the mining facilities are assumed to be constant (i.e., more runoff equals more mass loading into the site water inventory); and, measured evaporation rates from rock piles at other Canadian Shield mine sites (Macroline, 2008 as cited in Areva, 2011) indicate that evaporation from the top of the pile can be as high as 60% of rainfall, and that evaporation in other natural areas of the Canadian Shield is several hundred mm (>20 % of rainfall) (Singer and Cheng (2002). Sensitivity analysis in relation to flows and water quality is provided in both the Site Water Quality TSD (Section 4.3) and the Lake Water Quality TSD (Section 4.2 and 4.3.2). In these cases a range of flow conditions is provided and an average case and upper bound case water quality is provided (using 75th percentile values for chemistry inputs). It is considered that the sensitivity model runs as provided are appropriate since they are based on measured and modelled data developed following standard procedures such as those provided in MEND 2009 and GARD, References Areva, 2011; Hydrology of Waste Rock Piles in Cold Climates; Technical Appendix 5I of the Kiggavik Project Environmental Impact Statement. December Macroline, J., Investigations of water and tracer movement in covered and uncovered unsaturated waste rock, PhD. Dissertation, University of British Columbia, Vancouver, Canada. 2 Project No

59 COMMENT T-38 In response to NRCan-7 (Appendix 1.IV), the proponent indicates that the pit overflow estimate is revised to approximately 218 years after closure (from initial estimate of 78 years after closure). The proponent indicates that they will be able to monitor flux and water quality from the pits during operations and closure to allow for contingency measures to be implemented. The quality of water seeping from the open pits to groundwater was estimated by the proponent to be below guideline levels with the exception of Cadmium. Errors in water quality and amounts from these sources, including seepage rates into the pits would result in errors in pit water quality estimates. Once the pits are full and water is allowed to flow through a surface channel to Upper Marmion Reservoir and through groundwater, any errors in predicted pit water quality could result in higher than predicted concentrations of constituents of concern in surface water receptors. It is not clear if the proponent is planning to monitor the open pit water quality and seepage water quality for the duration of 218 years. Provide confirmation on whether pit water quality for 218 years will be included in the follow-up monitoring program and if not, provide justification for the decision. Site Water Quality TSD, Part A Introduction, Part B Supplemental Information Package; Conceptual Closure and Rehabilitation Plan TSD, Part A Introduction, Part B Supplemental Information Package; EIS, Appendix 1.IV Information Requests. As noted in Table 8-6 of the Final EIS/EA Report and Table 5-2 of the Conceptual Closure and Rehabilitation Plan TSD, Canadian Malartic Corporation has committed to monitoring pit water quality annually (as able based on safety considerations) beginning the first year of closure until a stable chemical condition is reached or until discharge occurs. After overflow, monitoring of discharge will occur monthly until 5 years of acceptable results are obtained.

60 COMMENT T-39 An essential component of all numerical hydrogeological models is a sensitivity analysis. Such an assessment of the proponent s water balance model is absent, but presumably could be conducted in order to assess the sensitivity of the water balance model to variations in input parameters. All models, including the one utilized by the proponent are subject to error. The proponent states in the response to NRCan-8 that In the water balance model all runoff and seepage is captured and the mass is therefore included in the final discharge water quality indicating that in order for model results to be valid, all seepage must be collected. In order to collect all seepage, the proponent will need to quantify seepage beneath the TMF and determine the proportion of seepage below the TMF versus through dams. This information will be needed in order to develop an appropriate seepage collection system at the detailed design phase. For example, if a significant amount of seepage occurs beneath the TMF, then the proponent will need to take measures to reduce seepage beneath the TMF (e.g. liner) and/or collect seepage via pumping wells that intercept this flow. In the proponent s response to MOE s comment, it is noted that 10% of the seepage reporting to the collection system along the east side of the TMF would likely report to Lizard Lake (a total of 227 m 3 /day of seepage). However it is not clear what impact this would have on Lizard Lake. This information will be necessary to have a clear understanding of what the effects of seepage will be on water quality in the receiving environment, as well as inform the design of mitigation to intercept seepage, and any monitoring networks. Provide an evaluation of the accuracy of the water balance model used to evaluate potential for near surface versus groundwater water quality influence, including a sensitivity analysis of the model to varied input parameters. Provide clarification on the seepage collection system. Specifically, will pumping wells be utilized to collect seepage from underneath the TMF? If not, please provide justification for this decision. Estimate seepage losses from the TMF, WRMF, PPCP and overburden storage using the groundwater model. Assess the effectiveness of the proposed seepage control measures, and assess the potential impact of seepage discharge to receptors. Provide a determination of seepage below the TMF versus seepage through dams. Identify contingency plans and mitigation measures if seepage beneath the TMF is greater than initially predicted. Provide a more detailed assessment of the impacts to Lizard Lake, which should be based on a more suitable and defensible estimate of seepage from the TMF to Lizard Lake.

61 Hydrogeology TSD, Part A Introduction, Part B Supplemental Information Package, Tech. Memo (Dec 2013), Sections ; Site Water Quality TSD, Part A Introduction, Part B Supplemental Information Package; Conceptual Closure and Rehabilitation Plan TSD, Part A Introduction, Part B Supplemental Information Package; EIS, Appendix 1.IV Information Requests. In response to comments received on the Final EIS/EA Report, Canadian Malartic Corporation hosted a water quality workshop on April 28, 2014 with the Government Review Team. We also initiated communications with the Regional Groundwater Group Leader for MOE s Northern Region who stated on May 15, 2014 that upon further clarification he is satisfied at this time with the estimates of seepage to Lizard Lake. Measures to limit, prevent and collect seepage from the TMF, WRMA, ore, low-grade ore, and overburden stockpiles have been developed at the conceptual level only at this time and consist of a series of collection ditches, and pumping stations. There are many proven ways to intercept seepage from a given site. During the detailed design stage for the Project additional drilling will be undertaken along the dam alignments, ditch alignments and near the edges of proposed stockpiles, and at that time it will be appropriate to further specify the details of the seepage collection system design. Considerations during detailed design will include bedrock and depth of overburden conditions, and use of pumping; however it is not possible for Canadian Malartic Corporation to fully define these measures at a detailed design level without appropriate funding and Project EIS/EA approval. As all incident water is accounted for in the receiving waters, it is immaterial whether the water flows through the dams or beneath the TMF. Further detail regarding the conservativeness of the water quality modelling approach is in the memorandum entitled Water Quality Background Information, provided as Attachment 4 of the Final EIS/EA Report Addendum. The water quality of seepage has been predicted and assessed in the Final EIS/EA Report. All infiltration from Project facilities was assigned a water quality (as identified and discussed in the responses to information requests from the Draft EIS/EA Report) and direct discharge of this water from the facilities was evaluated. Infiltration water is expected to be compliant with applicable MMER and O. Reg 560/94 criteria. In addition, concentrations for each potential point source were considered (as part of IR-MOE-NR-GW-16 in Appendix 1.IV of the Final EIS/EA Report) and it was found that direct discharge of these concentrations into a water body would not result in adverse aquatic impacts. The water quality assessment considered sensitivity in relation to flows and water quality as provided in both the Site Water Quality TSD (Section 4.3) and the Lake Water Quality TSD (Section 4.2 and 4.3.2). The sensitivity analysis considered a range of flow conditions ranging from 100-year dry to 100-year wet and average case and upper bound water quality scenarios (using 75 th percentile values for chemistry inputs). It is considered that the sensitivity model runs as provided are appropriate since they are based on measured and modelled data developed following standard procedures such as those provided in MEND 2009 and GARD, Project No

62 At the request of the Government Review Team, additional 3D groundwater modelling efforts were undertaken for the eastern portion of the TMF. The preliminary 3D groundwater model was constructed using available information and, through this evaluation, it was shown that capture of greater than 90% of seepage could be achieved by the proposed control system given the current TMF design configuration and the current understanding of the tailing properties and geologic conditions of the site. Further details of this modelling evaluation are provided in the memorandum entitled Tailings Management Facility, 3D Groundwater Modelling provided as Attachment 3 of the Final EIS/EA Report Addendum. In light of the results of the newly undertaken groundwater modelling, it is considered that the assumed seepage capture efficiency is realistically achievable based on the conceptual design. During the detailed design stage additional information collected will be used to develop a more robust modelling evaluation to refine and optimize the design of the seepage collection system. It is the intent of Canadian Malartic Corporation to work with the design engineers and the applicable regulatory agencies to ensure that future data collection and the development of predictive models will meet both the requirements of engineering design and needs of the agencies with respect to permitting requirements. 3 Project No

63 COMMENT T-40 The Proponent has assumed no seepage out of facilities collecting water, and from facilities such as the TMF. HDPE liners will degrade over time and thereby increase seepage and interflow rates. Conservative assumptions about hydraulic conductivities for dams, overburden, and bedrock need to be made, and sensitivity analyses conducted based on higher than expected conductivities (e.g. by assuming the maximum measured conductivities instead of the geometric mean). At the TMF and WRMA, seepage through containment dams constructed of waste rock will likely be large due to their relatively high hydraulic conductivity (i.e. they are not proposed to be constructed with a low permeability core). This seepage is likely to have higher levels of contamination as compared to surface water runoff and therefore may pose a larger risk, particularly in the post-closure phase. Groundwater/seepage modelling conducted for various Project components such as the Tailings Management Facility (TMF), Waste Rock Management Area (WRMA), ore and overburden stockpiles will provide a clear understanding of what the effects of seepage will be upon water quality in the receiving environment, as well as inform the design of mitigation to intercept seepage, and any monitoring networks. Conduct groundwater/seepage modeling for the Tailings Management Facility (TMF), Waste Rock Management Area (WRMA), and the various ore and overburden stockpiles. Site Water Quality TSD: Section Seepage Hydrogeology TSD Version 2 On April 28, 2014 Canadian Malartic Corporation hosted a water quality workshop with the Government Review Team. We also initiated communications with the Regional Groundwater Group Leader for MOE s Northern Region who stated on May 15, 2014 that upon further clarification he is satisfied at this time with the estimates of seepage to Lizard Lake. Measures to limit, prevent and collect seepage from the TMF, WRMA, ore, low-grade ore, and overburden stockpiles have been developed at the conceptual level only at this time and consist of a series of collection ditches, and pumping stations. There are many proven ways to intercept seepage from a given site. During the detailed design stage for the Project additional drilling will be undertaken along the dam alignments, ditch alignments and near the edges of proposed stockpiles, and at that time it will be appropriate to further specify the details of the seepage collection system design. Considerations during detailed design will include bedrock and depth of overburden conditions, and use of pumping; however it is not possible for Canadian Malartic Corporation to fully define these measures at a detailed design level without appropriate funding and Project EIS/EA approval.

64 The water quality of seepage has been predicted and assessed in the final EIS/EA Report. All infiltration from Project facilities was assigned a water quality (as identified and discussed in the responses to information requests from the Draft EIS/EA Report) and direct discharge of this water from the facilities was evaluated. Infiltration water is expected to be compliant with applicable MMER and O. Reg 560/94 criteria. In addition, concentrations for each potential point source were considered (as part of IR-MOE-NR-GW-16 in Appendix 1.IV of the Final EIS/EA Report) and it was found that direct discharge of these concentrations into a water body would not result in adverse aquatic impacts. At the request of the Government Review Team, additional 3D groundwater modelling efforts were undertaken for the eastern portion of the TMF. The preliminary 3D groundwater model was constructed using available information and, through this evaluation, it was shown that capture of greater than 90% of seepage could be achieved by the proposed control system given the current TMF design configuration and the current understanding of the tailing properties and geologic conditions of the site. Further details of this modelling evaluation are provided in the memorandum entitled Tailings Management Facility, 3D Groundwater Modelling provided as Attachment 3 of the final EIS/EA Addendum. In light of the results of the newly undertaken groundwater modelling, it is considered that the assumed seepage capture efficiency is realistically achievable based on the conceptual design. During the detailed design stage additional information collected will be used to develop a more robust modelling evaluation to refine and optimize the design of the seepage collection system. It is the intent of Canadian Malartic Corporation to work with the design engineers and the applicable regulatory agencies to ensure that future data collection and the development of predictive models will meet both the requirements of engineering design and needs of the agencies with respect to permitting requirements. 2 Project No

65 COMMENT T-41 The hydrographs for BRH-0003B, BRH-0013, and BRH-0001B are all similar in slope to that for BRH-0009 during the decline in Marmion Reservoir water levels. We question the Proponent s conclusion that there is no direct hydraulic connection between these wells and Marmion Reservoir. This information will be necessary to have a clear understanding of what the effects of seepage will be on water quality in the receiving environment. Re-evaluate the degree of hydraulic connection between groundwater wells and Marmion Reservoir. The Proponent should clarify whether the hydraulic connection has any bearing on the possibility of seepage flowing to receiving water bodies and quantify the effect of such a connection. Hydrogeology TSD, Section 2.4 Groundwater Levels, (and Figures 2-12, 2-13) The hydraulic connection was evaluated as being indirect and seasonal in nature. The wells are located in the vicinity of the Marmion Reservoir. The Marmion Reservoir was shown to have limited influence on these locations based on observations of short term fluctuations in reservoir water level relative to fluctuations in the monitoring wells. Thus the hydraulic connection is not direct, but rather more seasonal in nature. This conclusion is based on the data as presented. This data was used in the evaluation of potential impacts at a Final EIS/EA stage of decision making. Additional data will be collected, and analyses completed during the detailed design stage of the Project once EIS/EA approval is obtained. Water quality of seepage water and direct discharge of water from all facilities is expected to be compliant with applicable MMER and O. Reg 560/94 criteria. Water quality concentrations for each potential point source were also considered as part of IR-MOE-NR-GW-16 in Appendix 1.IV of the Final EIS/EA Report and it was found that direct discharge of these concentrations into a water body would not result in adverse aquatic impacts. During the detailed design stage of the Project, additional drilling will be undertaken along the dam alignments, ditch alignments and near the edges of proposed stockpiles. With this additional information, a more robust modelling evaluation will be undertaken to refine and optimize the design of the seepage collection system. Monitoring programs will be conducted and refined as site data refines the conceptual model. It is the intent of Canadian Malartic Corporation to work with the applicable regulatory agencies to develop appropriate monitoring programs and plans that will meet the requirements of engineering design, the needs of the agencies with respect to permitting requirements, and evaluation of potential for impacts, such that predictions can be verified, trends identified, and adaptive management strategies can be implemented if necessary. Through this process, ongoing monitoring and adaptive management if necessary, seepage is not expected to have an impact on the receiving water bodies.

66 COMMENT T-42 The Ontario Ministry of the Environment commented on the location of monitoring wells: Monitoring well locations for water levels are focused on the Marmion Lake reservoir (located along the shore). However, as water will generally discharge back to the reservoir, it is not really the sensitive "receptor". Rather, it would be the smaller surface water features beyond the 11 impacted watersheds identified in Table It would be better that the monitoring program focus on assuring that features that were not to be impacted are not impacted. Monitoring wells should be more to the east of the pits, towards surface water features beyond the predicted drawdown. And in this case, monitoring need not be limited to groundwater levels - water levels in surface water features should also be monitored. Surface water features to be monitored should include those within the drawdown cone, just beyond the cone, and some well beyond the cone as background to differentiate dewatering effects from natural. A reduction in local groundwater levels from pit dewatering could also result in reduced flow in smaller surface water features located within the drawdown cone from the dewatering. Most of the surface water features located within this drawdown cone are located in areas that will be significantly disrupted by the excavation of the mine and the construction of stockpiles, but there are some smaller features located beyond this area which could be impacted. The proposed monitoring program should be revised to ensure that surface water features that are not anticipated to be impacted my mining activities are also monitored to confirm these predictions of impact. The proponent s response indicates that monitoring locations will be located as appropriate, and that monitoring programs will be refined as site data refines the conceptual model. This commitment is adequate for the purposes of the EA. A detailed monitoring plan will be required to be submitted for approval in support of any permits and approvals for the Project. Provide confirmation that the impact of groundwater lowering on small surface water features will be monitored , 6.1.3, Yes, water levels in surface water features will be monitored. Canadian Malartic Corporation understands the importance of reference sites and the role of environmental monitoring in the verification of predictions. Groundwater monitoring programs will be refined as site data refines the conceptual groundwater model. As outlined in Chapter 8 Environmental Management Planning, Canadian Malartic Corporation will work with the applicable regulatory agencies to develop appropriate monitoring programs that will meet the permitting requirements and allow for adaptive management strategies if necessary.

67 COMMENT T-43 The EIS states that the dam foundation for the TMF will be stripped of organic soils, with perimeter dykes constructed of compacted waste rock. Without stripping of all permeable material at the foundation, seepage from the TMF may be difficult to manage. This is of special concern with the Reclaim pond, where contact water will migrate to groundwater reporting to surface waters. With the uncertainties in the Proponent s metal leaching predictions, there are concerns that this effluent seepage will not meet water quality criteria and have direct impacts to water quality in Lizard Lake. Provide additional mitigation measures and consider adaptive management plans to manage effluent from the Reclaim pond and TMF in the event that effluent and receiving water quality criteria cannot be met. Revise the effluent and receiving water quality predictions for the TMF based on revised geochemical analysis of tailings materials. EIS Chapter 5 Project Description Version 2 Page On April 28, 2014 Canadian Malartic Corporation hosted a water quality workshop with the Government Review Team. We also initiated communications with the Regional Groundwater Group Leader for MOE s Northern Region who stated on May 15, 2014 that upon further clarification he is satisfied at this time with the estimates of seepage to Lizard Lake. Measures to limit, prevent and collect seepage from the TMF, WRMA, ore, low-grade ore, and overburden stockpiles have been developed at the conceptual level only at this time and consist of a series of collection ditches, and pumping stations. There are many proven ways to intercept seepage from a given site. During the detailed design stage for the project additional drilling will be undertaken along the dam alignments, ditch alignments and near the edges of proposed stockpiles, and at that time it will be appropriate to further specify the details of the seepage collection system design. Considerations during detailed design will include bedrock and depth of overburden conditions, and use of pumping; however it is not possible for Canadian Malartic Corporation to fully define these measures at a detailed design level without appropriate funding and Project EIS/EA approval. The water quality of seepage has been predicted and assessed in the Final EIS/EA Report. All infiltration from Project facilities was assigned a water quality (as identified and discussed in the responses to information requests from the Draft EIS/EA Report) and direct discharge of this water from the facilities was evaluated. Infiltration water is expected to be compliant with applicable MMER and O. Reg 560/94 criteria. In addition, concentrations for each potential point source were considered (as part of IR-MOE-NR-GW-16 in Appendix 1.IV of the Final EIS/EA Report) and it was found that direct discharge of these concentrations into a water body would not result in adverse aquatic impacts.

68 At the request of the Government Review Team, additional 3D groundwater modelling efforts were undertaken for the eastern portion of the TMF. The preliminary 3D groundwater model was constructed using available information and, through this evaluation, it was shown that capture of greater than 90% of seepage could be achieved by the proposed control system given the current TMF design configuration and the current understanding of the tailing properties and geologic conditions of the site. Further details of this modelling evaluation are provided in the memorandum entitled Tailings Management Facility, 3D Groundwater Modelling provided as Attachment 3 of the Final EIS/EA Addendum. In light of the results of the newly undertaken groundwater modelling, it is considered that the assumed seepage capture efficiency is realistically achievable based on the conceptual design. During the detailed design stage additional information collected will be used to develop a more robust modelling evaluation to refine and optimize the design of the seepage collection system. It is the intent of Canadian Malartic Corporation to work with the design engineers and the applicable regulatory agencies to ensure that future data collection and the development of predictive models will meet both the requirements of engineering design and needs of the agencies with respect to permitting requirements. 2 Project No

69 COMMENT T-44 A new figure, Figure 5-11, was recently added to the EIS in Chapter 5 Project Description. Figure 5-11 identifies existing natural watercourses in the vicinity of the process plant site and adjacent to the waste rock stockpile. With the inclusion of the new Figure 5-11 and the comparison to Figure 5-10 it seems that the Intermediate Collection Pond (ICP) will be constructed within the location of a natural watercourse. In the Aquatic Environment TSD, Figure 3-2 identifies this watercourse as API 14 and Table 2-6 identifies the fish species present there. The use of API 14 for the development of the ICP is not apparent in Chapter 5 of the EIS. Under the MMER, API 14 would have to be added to Schedule 2 in order to allow its use as a storage pond for contact water. The ICP is not discussed in the updated Assessment of Alternatives TSD. A description of this pond and the rationale for the selected location should be included in the Alternatives Assessment for Mine Waste Disposal. Provide a description of the Intermediate Collection Pond and the purpose of the ICP in the Alternatives Assessment for Mine Waste Disposal. This description should include the rationale for the site selection of the pond. Alternative siting of the ICP should be assessed. Hammond Reef Gold Project Environmental Impact Statement (EIS) Chapter 5 Project Description Figure 5-10 Surface Water Drainage Plan, Figure 5-11 Plan View of Process Plant Site Alternatives Assessment Report TSD The Alternatives Assessment Report provides a description of WRMF-3, including its associated Intermediate Collection Pond (ICP). As stated, the WRMF-3 footprint is approximately 2.1 km 2 and is located on top of a ridge sloping down to the west and to the east. Foundation conditions include shallow bedrock underlying thin layer of dense till. Baseline aquatic studies indicate Finescale Dace, Northern Redbelly Dace and Fathead Minnow presence in the pond within the footprint. The haul road length would be approximately 1.8 km. The Alternatives Assessment Report goes on to evaluate the impacts of each of the WRMF alternatives to the aquatic environment, including impacts to fish bearing lakes and the total area of that impact for each alternative. The Report identifies WRMF-3 as affecting 1 fish bearing lake with a total area of 2.8 ha. The final conclusion is that WRMF-3 is the preferred alternative. Despite the aquatic habitat loss, it proves to be the most feasible alternative when all criteria are considered. As described in Chapter 5, Project Description, the WRMF will include a runoff collection system, of which the Intermediate Collection Pond (ICP) will be a part. A runoff collection ditch will be excavated around the entire

70 WRMF, collecting the runoff into pumping stations situated at topographic lows. The selected site of the ICP is the low point located directly between the WRMF and the truck shop. No other alternative sites for the ICP would be feasible. 2 Project No