Notice of Alteration: New Britannia Mill

Hudbay Minerals Inc.

Notice of Alteration: New Britannia Mill

Prepared by: Prepared for: AECOM Canada Ltd. 99 Commerce Drive Winnipeg MB R3P 0Y7

Hudbay Minerals Inc. Manitoba Business Unit PO Box 1500 1 Company Road Flin Flon, MB R8A 1N9

Date: March 2019

Project #: 60567492

Distribution List

# Hard Copies PDF Required Association / Company Name

2 Manitoba Sustainable Development Environmental Approvals Branch 2 Hudbay Minerals Inc 1 Thompson Dorfman Sweatman 1 AECOM Canada Ltd.

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AECOM Canada Ltd. 99 Commerce Drive Winnipeg MB R3P 0Y7 Canada T: 204.477.5381 F: 204.284.2040

Siobhan Burland Ross, M.Eng., P.Eng A/Director, Environmental Approvals Branch Manitoba Sustainable Development 1007 Century Street Winnipeg, Manitoba R3H 0W4

March 4, 2019

Project # 60567492

Dear Ms Burland Ross: Subject: Notice of Alteration:

New Britannia Mill Please find enclosed two hard copies and one electronic copy of the Notice of Alteration (NOA) form and supporting information to obtain approval for the upgrades at New Britannia Mill (Environment Act License No. 1878 S3 RR). A cheque for the application fee of $7,500 is included with this application. Should you have any questions regarding the Project or the content in this report, please do not hesitate to contact Cliff Samoiloff at 204-928-7427. Sincerely, AECOM Canada Ltd.

Cliff Samoiloff, B.Sc., EP(CEA) Mining Market Sector Lead, Canada Senior Scientist, Environment

KC:rz Encl. cc:

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Statement of Qualifications and Limitations The attached Report (the “Report”) has been prepared by AECOM Canada Ltd. (“AECOM”) for the benefit of the Client (“Client”) in accordance with the agreement between AECOM and Client, including the scope of work detailed therein (the “Agreement”).

The information, data, recommendations and conclusions contained in the Report (collectively, the “Information”):

is subject to the scope, schedule, and other constraints and limitations in the Agreement and the qualifications contained in the Report (the “Limitations”);

represents AECOM’s professional judgement in light of the Limitations and industry standards for the preparation of similar reports;

may be based on information provided to AECOM which has not been independently verified; has not been updated since the date of issuance of the Report and its accuracy is limited to the time period and

circumstances in which it was collected, processed, made or issued; must be read as a whole and sections thereof should not be read out of such context; was prepared for the specific purposes described in the Report and the Agreement; and in the case of subsurface, environmental or geotechnical conditions, may be based on limited testing and on the

assumption that such conditions are uniform and not variable either geographically or over time.

AECOM shall be entitled to rely upon the accuracy and completeness of information that was provided to it and has no obligation to update such information. AECOM accepts no responsibility for any events or circumstances that may have occurred since the date on which the Report was prepared and, in the case of subsurface, environmental or geotechnical conditions, is not responsible for any variability in such conditions, geographically or over time.

AECOM agrees that the Report represents its professional judgement as described above and that the Information has been prepared for the specific purpose and use described in the Report and the Agreement, but AECOM makes no other representations, or any guarantees or warranties whatsoever, whether express or implied, with respect to the Report, the Information or any part thereof.

Without in any way limiting the generality of the foregoing, any estimates or opinions regarding probable construction costs or construction schedule provided by AECOM represent AECOM’s professional judgement in light of its experience and the knowledge and information available to it at the time of preparation. Since AECOM has no control over market or economic conditions, prices for construction labour, equipment or materials or bidding procedures, AECOM, its directors, officers and employees are not able to, nor do they, make any representations, warranties or guarantees whatsoever, whether express or implied, with respect to such estimates or opinions, or their variance from actual construction costs or schedules, and accept no responsibility for any loss or damage arising therefrom or in any way related thereto. Persons relying on such estimates or opinions do so at their own risk.

Except (1) as agreed to in writing by AECOM and Client; (2) as required by-law; or (3) to the extent used by governmental reviewing agencies for the purpose of obtaining permits or approvals, the Report and the Information may be used and relied upon only by Client.

AECOM accepts no responsibility, and denies any liability whatsoever, to parties other than Client who may obtain access to the Report or the Information for any injury, loss or damage suffered by such parties arising from their use of, reliance upon, or decisions or actions based on the Report or any of the Information (“improper use of the Report”), except to the extent those parties have obtained the prior written consent of AECOM to use and rely upon the Report and the Information. Any injury, loss or damages arising from improper use of the Report shall be borne by the party making such use.

This Statement of Qualifications and Limitations is attached to and forms part of the Report and any use of the Report is subject to the terms hereof.

AECOM: 2015-04-13 © 2009-2015 AECOM Canada Ltd. All Rights Reserved.

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Quality Information Report Prepared By:

Kristiina Cusitar, BA, CET, EP(SAR) Environmental Assessor Irene Davies, EIT Environmental Engineer in Training

Report Reviewed By:

Cliff Samoiloff, B.Sc., EP (CEA)

Senior Scientist

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Executive Summary

This report has been prepared in support of a Notice of Alteration (NOA) to be submitted by Hudbay Minerals Inc. (Hudbay) for consideration by Manitoba Department of Sustainable Development Environmental Approvals Branch in relation to the New Britannia Mill Environment Act Licence No. 1878 S3 RR. This Notice of Alteration Report contains the information described in Manitoba Sustainable Development’s “Information Bulletin – Alterations to Developments with Environment Act Licenses” (October 2017). Hudbay proposes to refurbish and operate the existing New Britannia Mill located in the Snow Lake mining district in Northern Manitoba (the “Project”). The refurbished New Britannia Mill will process gold ore obtained from Lalor Mine and produce copper concentrate by flotation and bars of gold and silver extracted by cyanide leaching of flotation tailings. It will have a design capacity of 1,500 tonnes per day (tpd). It is anticipated that it will operate 24 hours per day, 362 days per year, with scheduled downtime for maintenance as required. Once operational, the New Britannia Mill will employ approximately 65 people full-time. There will be no change to the external footprint of the existing mill building. New components at the New Britannia Mill site will include an ore pad for the short-term storage gold ore obtained from the Lalor Mine, a new hopper that will be retrofitted onto the existing primary crusher building, two new crushers that will replace the crushers located inside the existing crusher buildings, a lime silo, and a flotation building that will be connected to the mill building via a new utility corridor. Hudbay expects that approximately 3.6 million tonnes of tailings will be produced over a period of gold production from Lalor of approximately seven years. Hudbay has reviewed two options for the management of the New Britannia Mill tailings: deposition of tailings in the adjacent Birch Lake Tailings Disposal Facility; or tailings deposition in the Anderson Tailings Impoundment Area (Anderson TIA) via a surface pipeline. Based on the assessment of tailings and water quality at both tailings facilities, it has been determined that the best option for tailings management is the disposal of tailings via a surface pipeline into the Anderson TIA with the allowance for a return water system. A pipeline corridor, approximately 6.8 km in length, will be established linking the New Britannia Mill with Anderson TIA via the Stall Concentrator. The corridor will contain three surface pipelines (the “Pipeline System”), running side by side, protected by an earthen cover to be constructed as part of this Project. One pipeline will direct tailings generated at the New Britannia Mill to the Stall Concentrator for ultimate deposit in Anderson TIA. A return water pipe will send water reclaimed from Anderson TIA to the New Britannia Mill via Stall Concentrator. The copper concentrate produced at Stall Concentrator will be pumped to New Britannia Mill via a third pipeline. The New Britannia Mill site and the end of the Pipeline System, the Stall Concentrator/Anderson TIA, are fully-developed and have been used for mining purposes for decades, and the route of the Pipeline System will run roughly parallel with an existing Manitoba Hydro transmission line right-of-way (ROW). No activity, component or impact of the proposed alteration will impede access to downstream resources or affect any current user’s ability to continue to exercise any recreational, commercial or subsistence use of these resources. The New Britannia Closure Plan will be updated to account for the new Project components and will be submitted to the Director of Mines for approval, along with any increase/decrease in financial assurance that

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may be required. In accordance with Hudbay’s experience with mine closure in the Snow Lake region, it is expected that closure activities will, in time, result in substantial return of the site to pre-Project conditions. The results of the environmental and socioeconomic effects assessment can be summarized as follows:

Topography

Construction and operation of the New Britannia Mill and Pipeline System will not affect the local topography. The mill site and the end of the Pipeline System in the Stall Concentrator/Anderson TIA site are both sites which are currently occupied by mining operations; and the route of the Pipeline System will run approximately parallel to an existing Manitoba Hydro ROW.

Wherever practicable, existing access roads and laydown areas will be used in order to minimize changes to topography. The closure phase will include restoration of any changes to topography of the site to match the pre-construction condition of the surrounding area to the extent practical.

Soil

None of the proposed construction or operation activities are expected to entail new impact to soil. Disturbed and exposed areas will be kept to a minimum with site restoration occurring as soon as is practical. Wastes generated during construction, including hazardous materials, will be collected in bins maintained at specific locations throughout the Project Site. The bins will be emptied on a regular basis for recycling and/or disposal at a licensed waste disposal facility. All disturbed areas will be re-vegetated following site closure.

Groundwater

Construction and operation of the New Britannia Mill and Pipeline System will not affect the local groundwater. There are no underground works involved with this Project, and no withdrawals of groundwater are required. No effects from waste management or accidents and spills are expected.

Surface Water

The existing facilities will continue to operate in accordance with the applicable Environment Act licenses. AECOM completed a water quality assessment to determine the effect on water quality of adding tailings from New Britannia Mill into Anderson TIA. This water quality assessment concluded that effluent discharge from the Anderson TIA will continue to meet regulatory criteria, and it is expected that effluent from Anderson TIA that flows into Anderson Creek and further downstream into Anderson Bay of Wekusko Lake will also continue to meet the required water quality guidelines. No additional water treatment will be required at the Anderson TIA final discharge point. Wastewater generated by the New Britannia Mill, including return water, grey water and sanitary sewage, will be stored in tanks and will be managed using existing licensed treatment facilities.

To prevent potential effects on surface water quality during construction, all physical activities near natural waterbodies will be carried out in accordance with DFO’s “Measures to Avoid Causing Harm to Fish and Fish Habitat,” and the Pipeline System has been designed to prevent spills and leaks. No impact to surface water quantity is expected during construction and operation. The majority of the water required for processing at New Britannia Mill will be recycled water from Anderson TIA or process water that

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is recycled within the mill itself. Only a minimal amount of freshwater from Snow Lake will be used for domestic purposes and reagent mixing.

Dust

The effect of dust during construction and operation will be Negligible to Minor. Areas to be cleared will be minimized, and vegetative buffers, where present, will be maintained to mitigate wind effects and overall potential dust migration. The crusher will be enclosed and equipped with a wet scrubber. All conveyors are either inside a building or enclosed in a gallery which contains dust. Trucks hauling materials will be covered to minimize dust coming off loads. Dust suppression activities, such as the use of approved dust control agents will be undertaken on unpaved roads including the upgraded New Britannia Truck Access Road and the new Pipeline System access road and at all times, vehicles will be required to adhere to Hudbay’s sped limits on main roads and access roads.

Air Emissions (Excluding Dust)

Air quality will not be adversely affected by emissions from equipment and vehicles. All vehicles used for the Project will comply with Environment Canada’s On-Road Vehicle and Engine Emission Regulations as required, vehicles and equipment will be well maintained, and idling will be kept to a minimum.

Noise and Vibration

At the New Britannia Mill site, noise generating activity will occur during construction and operation. On the Pipeline System portion of the Project, noise generating activity will occur largely only during construction. Acoustic assessments carried out by AECOM concluded that the effect of noise during the construction and operation phases of the Project will be Negligible following the implementation of proposed mitigation measures, including improved soundproofing on site buildings, installation of a sound barrier, modifications to backup alarms, equipment maintenance and operational controls.

All activities performed by Hudbay will be carried out in accordance with The Workplace Safety and Health Act and the Hudbay OHSAS 18000 certified management system, which will avoid potential effects on health and safety.

Protected and Other Vegetation

Although construction of the Pipeline System will result in a loss of vegetation, clearing will be kept to the minimum extent possible. No unique vegetation communities will be lost, and the species lost to clearing are common in the region. Although medicinal plants were observed in wetland areas during field studies, these wetlands (which are located adjacent to the New Britannia Mill site) will be avoided to the extent feasible during construction. At closure, the Project Site will be returned to native conditions to the maximum extent feasible. Once the infrastructure on the site has been removed and the site has been re-graded, disturbed areas will be re-vegetated with native vegetation species in accordance with the Closure Plan.

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Protected and Other Wildlife

The potential impact of loss of habitat on wildlife species will be Negligible. The cover classes affected by the construction of the Pipeline System are not unique to the Project Area, and there is an abundance of similar habitat types throughout the region.

Nesting birds that may use edge habitat available along the route of the Pipeline System will be able to continue to use this habitat following the development of the Project. No clearing will occur in the peak migratory bird nesting season, and no clearing will occur in the shoulder nesting season unless a nest search is conducted by a biologist prior to clearing.

It is anticipated that local wildlife are likely already accustomed to some level of noise based on the existing mining activity in the area, and there is very limited ideal habitat for protected wildlife species in the Project Region. If local wildlife are deterred from the Project Site, it is not anticipated that this will substantially affect wildlife as similar habitats are available in the Project Region. The potential risk of vehicle collisions with wildlife is considered low, and speed limits on access roads, local roads and Provincial highways will reduce the risk of wildlife collisions.

Aquatic Resources

There is no fish or fish habitat at the New Britannia Mill site or at the end of the Pipeline System (the site of the Stall Concentrator). The only waterbody within the Project Site is Snow Creek. The Pipeline System will cross Snow Creek via a modular steel bridge. No component of the Pipeline System, including the modular steel bridge, will be constructed below the high water mark. The bridge will be a clear-span structure, supported on abutments placed above the high-water mark. No instream works are anticipated to be required. Mitigation measures built into the design of the Pipeline System will appropriately mitigate the risks of any spills or leaks which could have an effect on fish and fish habitat. Any activities that occur near Snow Creek will be carried out in accordance with applicable DFO “Measures to Avoid Causing Harm to Fish and Fish Habitat” or other applicable standards. Some riparian vegetation will be cleared to construct the Pipeline System which may result in a potential loss of habitat at the proposed water crossing. However, clearing of riparian vegetation will be minimized to the extent feasible and the riparian vegetation that will be removed is common throughout the assessed length of Snow Creek. Based on desktop review, it is unlikely that protected fish species occur in any area which could be potentially affected by the Project. No protected fish species were identified within the Project Region during field studies. The proposed Project does not require undertaking any activities in or near Snow Lake; therefore, there will be no effect on fish or fish habitat in Snow Lake. Climate Although climate change effects due to greenhouse gas emissions are considered irreversible, the overall quantity of greenhouse gas emissions generated during construction and operation of the New Britannia Mill is considered to have a Negligible effect on climate change.

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Land Use As residual environmental effects on terrestrial and aquatic resources have been determined to be Minor to Negligible in magnitude, it is anticipated that the Project will not adversely impact the availability of plants, wildlife and fish for resource harvesting in the region. As a result, no change in land use is anticipated. Hudbay has had discussions with all of the registered trapline owners in the Project Area, and none have expressed any concerns with respect to the proposed Project. Hudbay maintains communication with these trappers.

Heritage Resources

There are no recorded heritage resources at the Project Site and the potential for any to be found is minimal. There will be no further disturbance beyond the Project Site during construction and operation.

Aesthetics

Project components are located in areas that have been previously disturbed as part of mining and transmission line projects and therefore no adverse change in the existing aesthetics is expected. The Project Site will be inspected on a regular basis for loose waste and debris in order to maintain a clean site, and waste and debris will be stored in bins and removed from the site on a regular basis.

Indigenous Peoples

The Project Site is not located near any First Nations communities or heritage location, and the Project does not appear to require occupation of lands known to be currently used for traditional purposes by Indigenous peoples. The New Britannia Mill site is a wholly developed operational site, which has been an active mining operation since 1948. Similarly, the end of the Pipeline System is within an active area that is occupied by Hudbay’s Stall Concentrator. The area in between the New Britannia Mill site and the Stall Concentrator, to be occupied by the Pipeline System, lies within the area subject to Town of Snow Lake By-law which, for reasons of human safety, prohibits hunting to all except registered trapline owners (none of whom is associated with an Indigenous community). Restrictions with respect to human safety generally apply to all users. No First Nation or Aboriginal resource (hunting, fishing, trapping) or traditional use that could be affected by the proposed Project was identified during the engagement process or in other public and stakeholder meetings. While harvesting of medicinal plants cannot be absolutely ruled out, no such use was identified in the engagement process and habitat conditions where potentially medicinal plants were observed are relatively common in the Project Region.

Traffic

Although vehicular traffic will increase slightly during construction and operation of the New Britannia Mill, the effect of traffic on the Town of Snow Lake is assessed to be minor. A traffic study completed by AECOM shows that no additional mitigation measures are required to accommodate the increase in truck traffic.

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It is recommended that mitigation measures and monitoring programs described in this report be implemented to ensure potential environmental effects are minimized and/or identified early so that appropriate action can be undertaken. Monitoring programs that have been recommended include construction monitoring, continued Environmental Effects Monitoring (EEM) and monitoring requirements under the existing Environment Act licenses, and the success of re-vegetation efforts at site closure. In summary, the residual environmental effects will be Negligible to Minor in magnitude with the implementation of mitigation measures identified and monitoring programs proposed. It is our opinion that based on the available information and documented assumptions the proposed Project is not likely to cause significant adverse environmental effects.

Aerial Image of the New Britannia Mill Site, 2014

Proposed New Britannia Mill Project Components

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Table of Contents page

Executive Summary ...................................................................... iii

1. General Information and Contact ......................................... 1

1.1 Project Overview .................................................................................... 1 1.1.1 Project Need ....................................................................................... 1 1.1.2 Cyanide Management ......................................................................... 1 1.1.3 Tailings Management .......................................................................... 2 1.1.4 Links to Other Facilities ....................................................................... 2 1.1.5 Environment Act Approval ................................................................... 2

1.2 Proponent Contact Information .............................................................. 3 1.3 Company Profile .................................................................................... 3 1.4 Historical and Current Context for Hudbay Operations in Snow Lake ... 3

1.4.1 New Britannia Mine and Birch Lake TDF ............................................. 4 1.4.2 Anderson TIA ...................................................................................... 4 1.4.3 Stall Concentrator ................................................................................ 5 1.4.4 Lalor Mine ........................................................................................... 5

1.5 Project Planning Process ....................................................................... 5 1.5.1 Gold Processing Alternatives ............................................................... 5 1.5.2 Tailings Disposal Alternatives .............................................................. 6 1.5.3 Other Design Improvements ................................................................ 9

1.6 Property Rights .................................................................................... 10 1.6.1 Portion of the Project Site at New Britannia ....................................... 10 1.6.2 Portion of the Project Site Connecting New Britannia with Stall

Concentrator (the Pipeline Route) ..................................................... 11 1.6.3 Portion of the Project Site at or near Stall Concentrator/Anderson

TIA .................................................................................................... 12

2. Project Information .............................................................. 13

2.1 Overview .............................................................................................. 13 2.2 Regulatory Requirements .................................................................... 13

2.2.1 Manitoba ........................................................................................... 13 2.2.2 Federal .............................................................................................. 13 2.2.3 Other Regulatory Restrictions ............................................................ 14

2.3 Overview of Project Components ........................................................ 14 2.4 New Britannia Mill Components ........................................................... 14

2.4.1 Ore Receiving and Handling System (New Feature) ......................... 15 2.4.2 Crushers (Upgrades/Replacements of Components in Existing

Buildings) .......................................................................................... 15

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2.4.3 Mill Building (Upgrades/Replacements of Components inside Existing Buildings) .......................................................................................... 15

2.4.4 Flotation Building (New) .................................................................... 15 2.4.5 Lime Silo (New) ................................................................................. 16

2.5 Production Processes .......................................................................... 16 2.6 Auxiliary Components .......................................................................... 17 2.7 Pipeline System Components .............................................................. 18

2.7.1 Mitigation Measures built into Pipeline Design ................................... 19 2.7.2 Tailings Pipe ...................................................................................... 20 2.7.3 Return Water Pipe ............................................................................. 20 2.7.4 Copper Concentrate Pipe .................................................................. 20 2.7.5 Fill Requirements .............................................................................. 20 2.7.6 Freeze Protection .............................................................................. 20 2.7.7 Pipeline System Road Crossings ...................................................... 21 2.7.8 Modular Steel Bridge ......................................................................... 21 2.7.9 Pipeline System Access Road ........................................................... 21 2.7.10 Clearing Requirements ...................................................................... 21

2.8 Route of the Pipeline System ............................................................... 21 2.8.1 Segment 1 (within the Townsite of Snow Lake) ................................. 22 2.8.2 Segment 2 (Approximately Parallel to Hydro ROW) .......................... 22

2.9 Production Capacity ............................................................................. 22 2.9.1 Water Requirements ......................................................................... 22 2.9.2 Air...................................................................................................... 23 2.9.3 Employees ........................................................................................ 23 2.9.4 Mill Materials ..................................................................................... 23

2.10 Equipment Use .................................................................................... 25 2.10.1 Solid and Hazardous Waste .............................................................. 26

2.11 Traffic ................................................................................................... 26 2.12 Emissions, Discharges and Waste ...................................................... 26

2.12.1 Atmospheric Emissions ..................................................................... 26 2.13 Continued Use of Existing Approved Facilities .................................... 27

2.13.1 Sewage ............................................................................................. 27 2.13.2 Anderson TIA .................................................................................... 27 2.13.3 Stall Concentrator .............................................................................. 27 2.13.4 Use of Other Existing Facilities .......................................................... 27

2.14 Project Phases and Proposed Schedule.............................................. 28

3. Scope of the Assessment ................................................... 29

3.1 Temporal Boundaries........................................................................... 29 3.2 Spatial Boundaries ............................................................................... 29

4. Environmental Setting ......................................................... 30

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4.1 Sources of Information ......................................................................... 30 4.2 Environmental Assessment Team ....................................................... 30 4.3 Environmental and Social Components ............................................... 30 4.4 Physical Environment .......................................................................... 33

4.4.1 Topography ....................................................................................... 33 4.4.2 Geology ............................................................................................. 33 4.4.3 Soil .................................................................................................... 34 4.4.4 Groundwater ..................................................................................... 34 4.4.5 Surface Water and Drainage ............................................................. 35

4.5 Atmospheric Environment .................................................................... 35 4.5.1 Air Quality .......................................................................................... 35 4.5.2 Noise and Vibration ........................................................................... 36 4.5.3 Climate .............................................................................................. 36

4.6 Terrestrial Environment........................................................................ 37 4.6.1 Scope of Terrestrial Assessment ....................................................... 37 4.6.2 Methods ............................................................................................ 37 4.6.3 Vegetation ......................................................................................... 38 4.6.4 Wildlife .............................................................................................. 38

4.7 Protected Species ................................................................................ 39 4.8 Aquatic Environment ............................................................................ 43

4.8.1 Methods ............................................................................................ 43 4.8.2 Results .............................................................................................. 47

4.9 Socio-Economic Environment .............................................................. 53 4.9.1 Parks and Natural Areas ................................................................... 53 4.9.2 Heritage Resources ........................................................................... 54 4.9.3 Regional Resource Use ..................................................................... 54

5. Public and Stakeholder Engagement ................................. 56

5.1 Public and Stakeholder Engagement Activities in May 2018 ............... 57 5.1.1 Stakeholder Meetings ........................................................................ 57 5.1.2 Public Information Session – May 29, 2018 ....................................... 58 5.1.3 Town of Snow Lake ........................................................................... 66

5.2 Public and Stakeholder Engagement Activities in December 2018 ..... 66 5.2.1 Stakeholder Meetings ........................................................................ 66 5.2.2 Public Information Session in December 2018 .................................. 68

5.3 Indigenous Engagement ...................................................................... 76 5.3.1 Hudbay’s Relationship with Indigenous Communities ........................ 76 5.3.2 Engagement Activities for the Proposed Project ................................ 76

6. Environmental Assessment and Mitigation Measures ..... 79

6.1 Effects Assessment Methodology ........................................................ 79 6.2 Topography .......................................................................................... 80

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6.3 Soil ....................................................................................................... 81 6.3.1 Erosion .............................................................................................. 81 6.3.2 Soil Compaction and Mixing of Soil Horizons .................................... 82 6.3.3 Materials and Waste Management .................................................... 83 6.3.4 Overall Impact to Soil ........................................................................ 83

6.4 Groundwater ........................................................................................ 83 6.5 Surface Water ...................................................................................... 84

6.5.1 Water Withdrawal .............................................................................. 84 6.5.2 Surface Water Quality along the route of the Pipeline System ........... 84 6.5.3 Tailings Deposition ............................................................................ 85 6.5.4 Waste Management .......................................................................... 88 6.5.5 Wastewater Management .................................................................. 88 6.5.6 Overall Impact on Surface Water Quality ........................................... 89

6.6 Atmospheric Environment .................................................................... 89 6.6.1 Dust ................................................................................................... 89 6.6.2 Air Emissions (excluding dust) ........................................................... 91 6.6.3 Noise and Vibration ........................................................................... 92 6.6.4 Overall Impact on Air ......................................................................... 94

6.7 Terrestrial Environment........................................................................ 94 6.7.1 Vegetation ......................................................................................... 94 6.7.2 Wildlife .............................................................................................. 98

6.8 Aquatic Resources ............................................................................. 100 6.8.1 Fish and Fish Habitat....................................................................... 100 6.8.2 Lower Trophic Level Biota ............................................................... 101 6.8.3 Protected Aquatic Species .............................................................. 101 6.8.4 Overall Impact on Aquatic Resources .............................................. 102

6.9 Climate ............................................................................................... 102 6.9.1 Overall Impact on Climate ............................................................... 102

6.10 Socio-Economic Effects ..................................................................... 102 6.10.1 Land and Resource Use .................................................................. 102 6.10.2 Heritage Resources ......................................................................... 104 6.10.3 Aesthetics ........................................................................................ 104 6.10.4 Effects on Indigenous Peoples ........................................................ 105 6.10.5 Traffic .............................................................................................. 106 6.10.6 Overall Impact on Socio-Economic Environment ............................. 107

6.11 Accidents and Malfunctions ............................................................... 107 6.11.1 Worker Health and Safety ............................................................... 107 6.11.2 Spills and Leaks .............................................................................. 107 6.11.3 Fires and Explosions ....................................................................... 108 6.11.4 Transportation Accidents ................................................................. 108 6.11.5 Power Failure .................................................................................. 109

6.12 Summary of Environmental Effects and Mitigation Measures ............ 109

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7. Monitoring and Follow-up ................................................. 120

7.1 Construction Monitoring ..................................................................... 120 7.2 Continued Monitoring Associated with the Operation of New Britannia

Mill ..................................................................................................... 120 7.2.1 MDMER........................................................................................... 120 7.2.2 Environment Act Licences ............................................................... 120 7.2.3 Success of Re-vegetation Efforts .................................................... 120 7.2.4 Dust Monitoring and Air Dispersion Modelling ................................. 121 7.2.5 New Britannia Mill Closure Plan Update .......................................... 121

8. Conclusion ......................................................................... 122

9. References .......................................................................... 127

List of Charts Chart 5-1: How People Heard About the Event ................................................................................. 59 Chart 5-2: How did you hear about the Community Information Session? ........................................ 69 Chart 5-3: Feedback on Previous Information Session ..................................................................... 70 Chart 5-4: Feedback on Presentation Information ............................................................................. 70 Chart 5-5: Project Support ................................................................................................................. 71

List of Tables Table 1-1: Proponent Contact Information ........................................................................................... 3 Table 2-1: Summary of Reagents and Additives Required for New Britannia Mill ............................ 23 Table 2-2: Equipment Use during Construction of the Mill ................................................................ 25 Table 2-3: Equipment Use during Construction of the Pipeline System ............................................ 25 Table 2-4: Estimated Daily Traffic Volumes during Operation ........................................................... 26 Table 4-1: Identification of Potential Environmental/Social Component Interactions with the

Project .............................................................................................................................. 32 Table 4-2: Climate Data for the Flin Flon Airport, Manitoba (1981-2010) .......................................... 37 Table 4-3: Federally and Provincially Listed Species that May Occur in the Project Region ............ 40 Table 4-4: Results of Breeding Bird Survey ....................................................................................... 42 Table 4-5: New Britannia 2018 Field Programs ................................................................................. 44 Table 5-1: Other Comments............................................................................................................... 60 Table 5-2: Other Discussion at the May Public Information Session ................................................. 61 Table 5-3: Summary of Discussions with Town of Snow Lake Mayor and Council, December 6,

2018 ................................................................................................................................. 66 Table 5-4: Feedback on Improving the Engagement Process........................................................... 72 Table 5-5: Additional Comments or Concerns ................................................................................... 73 Table 5-6: Other Discussions at the December Public Information Session ..................................... 74 Table 5-7: Summary of Discussions at OCN Meeting ....................................................................... 78

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Rpt-2019-03-04-Noa-New Britannia Mill-60567492-Final xiv

Table 6-1: Terms Used in Effects Assessment .................................................................................. 80 Table 6-2: Cover Classes and Areas ................................................................................................. 96 Table 6-3: Traffic Changes............................................................................................................... 106 Table 6-4: Summary of Environmental Assessment and Mitigation Measures ................................ 111 Table 6-5: Summary of Potential Accidents and Malfunctions and Measures to Mitigate Risk of

Occurrence .................................................................................................................... 118

List of Figures Figure 1: General Site Location Figure 2: Location of Project Components and Existing Hudbay Facilities Figure 3: Project Site Plan Figure 4: Property Ownership Figure 5: Spatial Boundaries of the Assessment Figure 6: New Britannia Mill Site Figure 7: New Britannia Mill Project Components Figure 8: Gold Production Process Figure 9: Proposed Pipeline System Segments Figure 10: Proposed Pipeline System Segment 1 Figure 11: Proposed Pipeline System Segment 2 Figure 12: Mass Balance Figure 13: Physiographic Setting Figure 14: Manitoba Basins and Watershed Boundaries Figure 15: Proposed Pipeline System Segment 2, Breeding Bird Survey Figure 16: Socio Economic Environment Figure 17: First Nations relative to the Project Region Figure 18: Vegetation Analysis

Appendices Appendix A Notice of Alteration Form Appendix B Correspondence with Manitoba Hydro and Manitoba Infrastructure Appendix C Traffic Impact Study Appendix D Air Quality Dispersion Modelling Report Appendix E Noise Impact Assessment Appendix F Aquatic Technical Data Report Appendix G Correspondence with Heritage Resources Branch Appendix H Public and Stakeholder Engagement Appendix I Indigenous Engagement Appendix J Water Quality Impact Assessment

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Rpt-2019-03-04-Noa-New Britannia Mill-60567492-Final 1

1. General Information and Contact

1.1 Project Overview

1.1.1 Project Need

Hudbay Minerals Inc. (Hudbay) proposes to refurbish and operate the existing New Britannia Mill to process copper, gold and silver ore from Lalor Mine. The New Britannia Mill site is located in the Snow Lake mining district in Northern Manitoba (Figure 1). The New Britannia site has been occupied by mine and milling operations since 1949 and has been in care and maintenance since 2005. Hudbay acquired the New Britannia site in 2015. The site includes the mine, mill and Birch Lake Tailings Disposal Facility (“Birch Lake TDF”) (operating under Environment Act Licence No. 1878 S3 RR (revised November 2, 1999)). The New Britannia site is in the Town of Snow Lake, immediately adjacent to Hudbay’s Snow Lake Camp (also sometimes called “the Lalor Camp”), which provides accommodation for approximately 300 people working in the Snow Lake area, primarily at the Lalor Mine. Hudbay’s Lalor Mine lies approximately 17 km to the southwest of the Town of Snow Lake (the “Town”) and Hudbay’s Stall Concentrator and Anderson Tailings Impoundment Area (“Anderson TIA”) lie approximately 10 km southeast of the Town. The purpose of a mill is to process ore into a product that can be further refined for market use. It uses a combination of mechanical (crushing and grinding) and chemical processes (flotation and leaching) to extract target metals from the ore. The refurbished New Britannia Mill will process gold ore obtained from Lalor Mine and produce copper concentrate by flotation and bars of gold and silver extracted by cyanide leaching of flotation tailings. It will have a design capacity of 1,500 tonnes per day (tpd). It is anticipated that it will operate 24 hours per day, 362 days per year, with scheduled downtime for maintenance as required.

1.1.2 Cyanide Management

Throughout its operations Hudbay maintains and complies with ISO 14001 Environmental Management and OHSAS 18001 Occupational Health & Safety Management Systems. Although Hudbay is an experienced operator of base metal milling facilities in Flin Flon and the Snow Lake region, recent experience does not include gold processing with the use of cyanide. For this reason, Hudbay intends to seek additional certification in relation to cyanide management. Hudbay will design and operate the proposed Project in accordance with the requirements of the "International Cyanide Management Code for the Manufacture, Transport, and Use of Cyanide in the Production of Gold" (“Cyanide Code”). The Cyanide Code was developed by a multi-stakeholder Steering Committee under the guidance of the United Nations Environmental Program (UNEP) and the then- International Council on Metals and the Environment (ICME). The Cyanide Code is a voluntary industry program which focuses on the safe management of cyanide and cyanidation mill tailings and leach solutions. The objective of the Cyanide Code is to improve the management of cyanide used in gold and silver mining and assist in the protection of human health and the reduction of environmental impacts.

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Companies that adopt the Cyanide Code must have their mining operations that use cyanide to recover gold and/or silver audited by an independent third party to determine the status of Cyanide Code implementation. Those operations that meet the Cyanide Code requirements can be certified. Audit results are made public to inform stakeholders of the status of cyanide management practices at the certified operation. The code is described at https://www.cyanidecode.org/about-cyanide-code/cyanide-code.

1.1.3 Tailings Management

Hudbay expects that approximately 3.6 million tonnes of tailings will be produced over a period of gold production from Lalor of approximately seven years. Hudbay has reviewed two options for the management of the New Britannia Mill tailings: deposition of tailings in the adjacent Birch Lake TDF; or tailings deposition in the Anderson TIA via a surface pipeline. Based on the assessment of tailings and water quality at both Birch Lake TDF and Anderson TIA, it has been determined that the best option for tailings management is the disposal of tailings via a surface pipeline into the Anderson TIA with the allowance for a return water system.

1.1.4 Links to Other Facilities

The proposed Pipeline System will be approximately 6.8 km in length and will be comprised of:

• Tailings Pipeline: Tailings will flow from New Britannia Mill to Stall Concentrator (approximately 635,000 m3/year).

• Return Water Pipeline: Return water will flow from Anderson TIA to New Britannia Mill (approximately 300,000 m3/year).

• Copper Concentrate Pipeline: Copper Concentrate will flow from Stall Concentrator to New Britannia Mill (approximately 70,000 m3/year).

In this report, the “Project” is comprised of the proposed upgrades to the New Britannia Mill together with the installation of the Pipeline System. Figure 2 displays the New Britannia Mill in context with the existing Hudbay facilities in the Snow Lake region and the proposed Pipeline System. The area of the New Britannia site to be occupied by the upgrades, together with the area of the Pipeline System is the “Project Site,” as shown on Figure 3.

1.1.5 Environment Act Approval

This report has been prepared in support of a Notice of Alteration (NOA) to be submitted by Hudbay for consideration by the Environmental Approvals Branch (EAB) in relation to the New Britannia Mill Environment Act License No. 1878 S3 RR. This Notice of Alteration Report contains the information described in Manitoba Sustainable Development’s “Information Bulletin – Alterations to Developments with Environment Act Licenses” (October 2017). A copy of the NOA Form is included in Appendix A.

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1.2 Proponent Contact Information

Table 1-1: Proponent Contact Information

Name of Project New Britannia Mill

Name of Proponent Hudbay Minerals Inc. (Hudbay)

Address of Proponent PO Box 1500, #1 Company Road, Flin Flon, Manitoba, R8A 1N9

Principal Contact Person for the NOA

Jay Cooper Director of Environment, Hudbay PO Box 1500, #1 Company Road, Flin Flon, Manitoba, R8A 1N9 Ph: 204-687-2667

Email: [email protected]

1.3 Company Profile

Hudbay has two active mines in Manitoba: the 777 Mine in Flin Flon, which is expected to continue operation until the fourth quarter of 2021, and the Lalor Mine near Snow Lake, which is expected to continue operation until approximately 2027. Hudbay is in the process of implementing the approved closure plan for Reed Mine, located in Grass River Provincial Park, which operated from 2014 until 2018 in accordance with Environment Act Licence No. 3065. Closure activities are expected to be concluded in 2020. Copper and zinc ore from the 777 Mine is concentrated in the Flin Flon Metallurgical Complex (FFMC). Zinc and copper ore obtained at the Lalor Mine is processed at the Stall Concentrator. Tailings from the Stall Concentrator are deposited via a pipeline into the Anderson TIA. Tailings from Stall Concentrator are also used in the production of paste backfill at the Lalor Paste Plant that was commissioned in 2018. Zinc concentrate from both the FFMC and the Stall Concentrator is processed to produce refined zinc in the FFMC (which includes the zinc pressure leach, cellhouse and zinc casting plant). These facilities are expected to continue in operation until the close of operations of the 777 Mine. Since closure of the Flin Flon copper smelter in June of 2010, copper concentrate has been shipped out of Manitoba for further processing. As of December 2018, Hudbay directly employed 1,371 people, with an annual payroll of $145.5 million (USD) in wages and benefits. In 2017, Hudbay paid approximately $6.9 million in municipal taxes and grants as well as making community investments and charitable donations of approximately $107,000.

1.4 Historical and Current Context for Hudbay Operations in Snow Lake

The Snow Lake Mining District has been developed for mining purposes for over 50 years. Hudbay has played an integral part in this history since the late 1950s, by operating many mines in the area including: Photo Lake, Chisel Lake, Stall Lake, Osborne Lake, Rod Mine, Spruce Point, Ghost Lake, Anderson Lake, Chisel North, Reed and Lalor.

mailto:[email protected]

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1.4.1 New Britannia Mine and Birch Lake TDF

The earliest known ore discoveries in the Snow Lake area occurred in the 1920’s. The Nor-Acme Mine discovery was made by A.L. Parres in 1927, and subsequent exploration was conducted from 1942 to 1945.1 The original Britannia Mine and mill, referred to as the Nor-Acme Mine, operated between 1949 and 1958, producing approximately 512,000 ounces of gold and 41,400 ounces of silver. The milling by-products were discharged primarily as tailings to the Birch Lake basin approximately 1.5 km northeast of the mine, with smaller quantities discharged to a swampy area directly east of the original mill, which is now the Province of Manitoba’s remediated former mine tailings area. Also during that time, the Nor-Acme Mine piped 227,000 tonnes of cyanide-treated refractory sulphide concentrate into an open impoundment (the Arsenopyrite Residue Stockpile) with the hope of eventually developing a safe and economical means of extracting precious metal from the mine waste. From 1959 to 1987 various companies conducted further exploration activities in the Snow Lake area, but the mill and mine remained closed during this period. In 1980, Hudbay purchased the former mill building (referred to as the Britannia Concentrator) for use as storage and warehouse space. In 1988, Nor-Acme Mines Limited amalgamated with High River Gold Mines Limited (HGR) and became the owner of the original Nor-Acme deposit. The site was re-opened as New Britannia Mine in 1995 under the control of TVX Gold Inc. (TVX) and HGR, and operations at the mine resumed with a focus on dewatering portions of the previous underground workings and advancing workings in the mineralized zone. At that time, TVX installed several monitoring wells into the confined sand-gravel aquifer underlying the mine site and an impermeable cap was placed on the Arsenopyrite Residue Stockpile to prevent oxidation and acidic, metal-contaminated runoff. Once the cap was placed, the Arsenopyrite Residue Stockpile became the property and responsibility of the Province of Manitoba. Ownership of the mine and mill operations changed to Kinross Gold and High River Resources in 1995 and it operated from 1995 until closure in late 2004. Garson Resources and Piper Capital acquired a 100% interest in the New Britannia Mine in December 2006. The two companies merged in June 2007 to form Garson Gold Corp. (Garson), with the intention of recommencing gold mine operations. In April 2010, Garson became a wholly-owned subsidiary of Alexis Minerals. Alexis Minerals did not in fact recommence operation of the New Britannia Mine. In 2008, Hudbay demolished the Britannia Concentrator and in 2010 this site became the location of the Snow Lake Camp. In 2015, Hudbay acquired the balance of the property with the intention of considering resumption of operations of the mill and Birch Lake TDF.

1.4.2 Anderson TIA

The Anderson TIA has been used for sub-aqueous disposal of tailings since commissioning of the Stall Concentrator in 1979. It operated, and continues to operate in accordance with the Metal Mining Effluents Regulation (now amended and re-named the Metal and Diamond Mining Effluent Regulations (MDMER)). The Anderson TIA was authorized originally by Manitoba Clean Environment Commission (CEC) Order No. 766 until receiving a new Environment Act Licence on June 20, 2018 (Environment Act Licence No. 3263), issued in authorization of a major alteration. The new licence authorizes expansion of

1 Information in this section is from The Nor-Acme Gold Mine Story by James R.B. Parres & Marc Jackson, 2005.

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Anderson TIA in contemplation of the full volume of tailings that might be generated in processing ore from the Lalor deposits, including both base metal and gold zones.

1.4.3 Stall Concentrator

The Stall Concentrator was commissioned at the same time as the Anderson TIA and has been in continuous operation since then, with the exception of brief periods during 1993-1994, 1999 and 2009. Stall Concentrator is currently used to process ore from Lalor Mine, producing copper and zinc concentrate, which is then shipped to Flin Flon for further processing.

1.4.4 Lalor Mine

The Lalor Mine commenced ore production in 2012 for copper, zinc and gold. It is operated in accordance with Environment Act Licence No. 3096. In 2016, Hudbay filed a Notice of Alteration to the Lalor Mine to add the Lalor Paste Plant. The alteration was approved on January 30, 2017. The Lalor Mine, like many underground mining operations, utilizes “backfill”, often comprised of waste rock, to fill voids that are created by extraction of rock during underground mining. Backfill requirements for the Lalor Mine are 6.4 million tonnes of rock fill assuming 100% of the voids are filled. The purpose of a paste backfill plant is to produce an alternative source of backfill which can both stabilize underground workings and produce environmental advantages. Because of these advantages, the use of a paste backfill plant is regarded as a best practice in the mining industry. Paste backfill is created by mixing tailings generated by a mining operation with water and cement or a similar binding agent. Paste backfill is distributed into the voids in the mine and then gains compressive strength over time. Using paste backfill is a sustainable way to manage tailings and it increases operational safety within a mine. Using paste backfill as opposed to waste rock will extend the life of a mine by creating greater underground efficiency. It also recycles tailings in a way that prevents the formation of acid rock drainage and reduces the need for storage of tailings in a tailings impoundment area. Hudbay has been successfully operating a paste backfill plant at the 777 Mine in Flin Flon since 2003 and now also operates the Lalor Paste Plant at the Lalor Mine using tailings from Stall Concentrator.

1.5 Project Planning Process

In its planning process, Hudbay considered four options for processing Lalor gold ore and two options for tailings management. The following sections provide details of these main alternatives and also describe design improvements that were made after the public engagement process commenced and as a result of environmental field work.

1.5.1 Gold Processing Alternatives

Hudbay considered the following options for processing gold ore:

• Not extracting gold ore. • Sending gold ore to Stall Concentrator or FFMC for processing by flotation only. • Adding a new gold circuit to the existing Stall Concentrator. • Refurbishing the existing New Britannia Mill.

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Hudbay selected refurbishment of the New Britannia Mill and associated facilities, for the following economic and environmental advantages:

• Not extracting gold ore would forgo the benefit of mine reserves identified in the Lalor deposits. • Processing by flotation only would result in reduced gold and silver recovery (approximately 60%)

and it would adversely impact the quantity of metals added to tailings. • Adding a gold circuit to Stall Concentrator would require an expansion of the existing building and

the capital cost of the expansion would be greater than refurbishment of the New Britannia Mill. • A limited number of upgrades will be required for the New Britannia Mill to become operational. • Combined use of the existing Stall Concentrator facilities together with upgrades to the New

Britannia Mill will result in optimizing the efficiency of ore processing and improving the quality of the product, without adversely influencing waste streams.l

• Upgrading the New Britannia Mill will enable a high level of recovery (approximately 90%) of gold and silver from the ore, thus maximizing the extraction of useful resources from Lalor Mine.

1.5.2 Tailings Disposal Alternatives

In its planning process, Hudbay considered two main options for tailings management associated with processing Lalor ore at the New Britannia Mill:

• Birch Lake TDF: This would involve expansion of the existing Birch Lake TDF to accommodate the new volume of tailings from New Britannia Mill and construction of a short pipeline (500 m) from the New Britannia Mill to the Birch Lake TDF. Two sub options, sub-aerial and sub-aqueous, were considered.

• Anderson TIA (sub-aqueous): This would involve construction of a pipeline from the New Britannia Mill to the Anderson TIA, via the Stall Concentrator.

1.5.2.1 Evaluation of the Birch Lake TDF Options

Hudbay retained BGC Engineering (“BGC”), a geotechnical firm with expertise in tailings dam integrity and tailings operation, to carry out an assessment of the alternatives involving the Birch Lake TDF. The Birch Lake Tailings Disposal Alternatives Report completed in 2016, considered both sub-aerial and sub-aqueous disposal. Since the Birch Lake TDF is adjacent to the New Britannia Mill, for both sub options, tailings would only have to be pumped a short distance and the infrastructure and dams are already in place. Both Birch Lake sub options would entail raising the existing dam structures. Further, because of the differences between the ore in the Lalor deposits and the ore historically processed at New Britannia, it had to be considered that tailings resulting from the processing of Lalor gold ore will differ in chemical composition from the historic New Britannia tailings.

Sub-Aqueous Disposal

Sub-Aqueous Disposal would require maintaining a permanent water cover to minimize oxidation. Tailings would be transported by a floating pipeline into the Birch Lake TDF. This would allow for the movement of the pipeline to specific areas within the Birch Lake TDF. Due to the limited storage capacity of the Birch Lake TDF, the existing perimeter dams would need to be raised and/or the construction of new dams would be required to accommodate the elevated pond water level. Some advantages of Sub-Aqueous Disposal are that the potential for acid rock drainage (ARD) producing conditions are controlled and the existing polishing pond would be maintained to assist with water treatment and management.

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Based in large part on the analysis done by BGC, the disadvantages of Sub-Aqueous Disposal were found to be:

• Water cover would have to be maintained over the tailings in perpetuity which imposes an additional risk of potential dam failure, compared with the lower risk activities that would be associated with commissioning the Birch Lake TDF in its present state.

• The water level in the Birch Lake TDF would have to be monitored to ensure tailings are not left exposed beyond the estimated acid generation lag time.

• Additional treatment, over and above attenuation, would be required to maintain the quality of effluent discharged to the environment.

• Seepage from the Birch Lake TDF would likely increase as a function of higher water levels which may result in the need for continual capture and seepage pumpback to the facility.

Sub-Aerial Disposal

Sub-Aerial Disposal would entail the sequential deposition of tailings slurry in thin layers around the perimeter of the Birch Lake TDF. This would create exposed tailings beaches, similar to the existing layout. Dam expansion would still be required for this option, although the height requirement would be lower than for the sub-aqueous option. The tailings are expected to be acid generating and, although a small submerged area would continue to exist, an active water treatment plant would be required to achieve effluent and in-stream water quality limits. One advantage of Sub-Aerial Disposal is that the required submerged area would be smaller in size than for the sub-aqueous disposal method. This reduces the geotechnical risk associated with storing water against a dam structure in perpetuity. Another advantage is that the volume and associated costs of earthworks required would be less than for the sub-aqueous disposal method. Based in large part on the analysis done by BGC, the disadvantages of Sub-Aerial Disposal were found to be:

• Exposed tailing beaches would result in the generation of ARD within the facility, which over time could affect both surface water and groundwater quality.

• Exposed tailings could also result in generation of dust which would be a risk to receptor health (both human receptors and wildlife in the area).

• Active treatment will be required to treat the acid generated and control the metals released as a result of long term acidic conditions.

• Perimeter surface water diversions may be required to limit the volume of non-contact runoff draining to the Birch Lake TDF and require water treatment.

• A dry cover closure with revegetation would be difficult to achieve due to the acidic nature of the tailings. The tailings water would affect salinity and restrict vegetation growth.

• It would be difficult to achieve sufficiently certain mitigation of risks to the health of humans and wildlife associated with: o Potential leaching of metals into the food chain by way of groundwater contamination

caused by metal leaching. o Dispersion of airborne contaminants in dust collecting on vegetation that is foraged by local

wildlife.

1.5.2.2 Anderson TIA

The Anderson TIA has been in use since 1979, when a control dam was built at the east end of Anderson Lake across Anderson Creek to provide water discharge control from the Anderson TIA. Anderson Dam

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contains a controlled decant pipe that passes discharge from the Anderson TIA into Anderson Creek. Anderson Creek is a shallow creek that flows into Anderson Bay of Wekusko Lake. Since 1979, tailings have been pumped via a surface pipeline with an earthen cover to the north shore of the Anderson TIA. Tailings are then distributed across the northern and western portions of the Anderson TIA via a movable floating pipe. The overall concept in operation of the Anderson TIA is to place all tailings into the Anderson TIA underwater, keeping all of the tailings submerged to prevent oxidation. Effluent from the Anderson TIA is discharged intermittently to Anderson Creek via the regulated final discharge point in accordance Environment Act Licence No. 3263 and the requirements of the MDMER. During winter, discharge is typically shut off at Anderson Dam and remains shut off until the freshet flows commence and ice breakup occurs in spring. Tailings are transported to the Anderson TIA from the Stall Concentrator via a surface pipeline with an earthen cover. At the Anderson TIA, a single 300 mm diameter floating pipeline extends into the water and then splits into two separate 200 mm diameter floating pipelines which discharge the tailings. Tailings are discharged simultaneously through the two pipelines (“tailings discharge”) in accordance with a deposition plan, developed approximately every three years. Anderson TIA supplies approximately 70% of the process water used currently at the Stall Concentrator via a pump house located on the north shore of the Anderson TIA. Power for the pump house is supplied via a transmission line running from a Hudbay-owned substation located nearby. As noted in the AECOM report, Environmental Assessment of the Proposed Expansion of the Anderson Tailings Impoundment Area, submitted to Manitoba Sustainable Development in August 2016, as of that date, approximately 13 M tonnes of tailings had been deposited into the Anderson TIA. Since the construction of Anderson Dam, the Anderson TIA has been operated at a typical water elevation of approximately 277.7 m. Discharge of water out of the Anderson TIA typically occurs only during the open-water season (usually May to October) as per its operating licence (Environment Act Licence No. 3263). Anderson Creek receives the discharge from both the decant pipe and emergency overflow spillway. The disadvantages of depositing tailings produced at New Britannia Mill in Anderson TIA were noted to be:

• Tailings historically deposited in Anderson TIA differ chemically from the tailings that will be produced at the New Britannia Mill. As a result, the impact of the tailings on Anderson TIA water quality had to be analyzed and considered in the assessment.

• Since the facilities are not contiguous, a pipeline corridor will have to be established to connect the New Britannia Mill to Anderson TIA.

Advantages of disposal in Anderson TIA were found to be:

• Sub-aqueous deposition limits exposure of tailings to air and subsequent generation of tailings dust, metal leaching and ARD (when exposed to both air and precipitation).

• The Anderson TIA is a licensed facility which has already been approved for expansion to contain the full volume of tailings which could be generated from all known Lalor deposits.

• The Anderson TIA has been subject to decades of water quality monitoring and other environmental studies and has proven effective in meeting all applicable regulatory requirements.

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• All of this information has been subject to recent Manitoba regulatory review in the course of Hudbay’s application for the major alteration to approve the above-noted expansion.

• Based upon water quality modeling utilizing ore samples obtained from the Lalor deposit, the assessment described below in this report demonstrates that discharge from the Anderson TIA will continue to meet all applicable regulatory requirements if tailings generated at the New Britannia Mill are deposited into Anderson TIA.

• The cost to establish the pipeline corridor between New Britannia Mill and Stall Concentrator/Anderson TIA is lower than the cost to expand the Birch Lake TDF.

• The tailings stream directed from New Britannia Mill to Stall Concentrator will mix with the base metal tailings which are now being directed to the Lalor Paste Plant. Thus, some New Britannia tailings will be diverted, as are base metal tailings, into paste production, rather than discharged into the Anderson TIA.

• In current operations, the Lalor Paste Plant cannot operate at times when Stall Concentrator is offline. The addition of New Britannia tailings will mean that the Paste Plant can continue in operation. This is significant because when tailings are used to make paste, they are diverted from the waste stream.

1.5.3 Other Design Improvements

Hudbay’s planning process produced three design decisions that were made after the public information process commenced. Route of the Pipeline System At the first public information meeting (described below in Section 5.1.2), Hudbay presented two options for the route of the Pipeline System and asked for feedback on the two route options. The two options were:

• Option 1: tracking an existing Manitoba Hydro Transmission Corridor. • Option 2: tracking PR 392.

Option 1 was selected based on feedback received at the public information session, environmental considerations, and constructability. Improvement in Copper Processing Secondly, a process improvement was added which required the addition of a third pipeline. The pipeline corridor had been intended to contain a tailings pipe carrying tailings from New Britannia Mill to Anderson TIA and a return water pipe. In the first iteration of the design, copper concentrate produced by flotation at New Britannia would have been trucked to Stall Concentrator. The copper concentrate would then have been mixed with the copper concentrate at Stall Concentrator, and trucked to Flin Flon for further filtration. After the first public information session, the design was improved to take advantage of efficiencies that can be achieved in processing copper ore at New Britannia with new equipment, rather than continuing to process it at Stall Concentrator. A third pipeline was added to the corridor so that copper concentrate can be pumped from Stall Concentrator to New Britannia. Efficiencies will be achieved from processing copper ore in one new centralized filtration system to be installed in New Britannia which Stall Concentrator could not support without upgrades. Ultimately when copper concentrate is shipped to

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market it will contain more concentrate and less water, making transportation more efficient with lower fossil fuel consumption. In addition, the original tailings pipeline design (which had been intended to direct tailings from the New Britannia Mill directly into Anderson TIA through a new tailings deposition line) was modified so that the New Britannia tailings will join up with the existing line which now directs tailings from Stall Concentrator into Anderson TIA. This improvement in design means that New Britannia tailings can be used to feed the Lalor Paste Plant, diverting a portion of the tailings from deposition in the TIA and instead sending them underground. As well, this means that the Paste Plant can continue to operate during times when Stall Concentrator is off-line for maintenance or other reasons. These design improvements were described in the second public information session and in the Indigenous engagement sessions (described below in Section 5). Re-location of Flotation Building After the public engagement processes described below in Section 5, the general arrangement plan for the New Britannia Mill site was improved, as described in Section 2.4.4, resulting in a decrease in noise effects along the southwestern edge of the property.

1.6 Property Rights

Figure 4 displays the Project Site together with underlying property rights. The Project Site is comprised of land over which there are three basic types of property rights:

• New Britannia Mill site in the Townsite of Snow Lake. • Land to be occupied by the Pipeline System, connecting the New Britannia Mill site with Hudbay’s

Stall Concentrator/Anderson TIA. • Land occupied by Hudbay’s Stall Concentrator/Anderson TIA (existing facilities).

1.6.1 Portion of the Project Site at New Britannia

The first portion of the Project Site, the New Britannia Mill site, is held by Hudbay pursuant to a Crown Land General Permit and mineral interests as follows:

Mineral Lease Mineral Claim

ML61 P6557B General Permits GP1856 GP4209 GP5395 - The New Britannia Mill site is within the Townsite of Snow Lake and is fully occupied by existing mining facilities and surrounded by developed uses. This Project will require water obtained via a pumphouse located on land on the north shore of Snow Lake, also within the Townsite of Snow Lake. Currently, Hudbay maintains this pumphouse and it is used as the water source for the Town of Snow Lake municipal golf course. The previous owner of the New Britannia operation held Water Rights Licence No. 95-18, which entitled it to use the water obtained via this pumphouse, but which expired upon transfer of ownership of the facilities to Hudbay. Hudbay will

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apply for a new Water Rights Licence, which it expects to receive prior to the commencement of the operations outlined in this proposal.

1.6.2 Portion of the Project Site Connecting New Britannia with Stall Concentrator (the Pipeline Route)

The second portion of the Project Site consists of the pipeline route that will connect New Britannia Mill with Stall Concentrator. The pipeline route is considered in two segments. The first segment overlies General Permits and mineral interests held by Hudbay as follows: General Permit Mineral Lease

GP3379 ML61

GP5395 -

Mineral Claim P6558B CB9419 P6560B CB9417 P6559B CB6444 P6566B - The second segment, with one exception, overlies General Permits and mineral interests held by Hudbay. The first portion, Mineral Claim MB 5892, is held by Peter C. Dunlop, as shown on Figure 4. Application has been made for a Crown Land General Permit to permit use and occupation of the Peter C. Dunlop claim area for this Project. In its application for the General Permit, Hudbay has provided assurance that its intended operations will not impede Peter C. Dunlop’s right to access Mineral Claim MB5892 for purposes of mineral exploration. Hudbay expects to receive the general permit during the period in which this NOA is being considered. The balance of the second segment of the Pipeline Route overlies General Permits and mineral interests held by Hudbay as follows: Mineral Leases

M5706 M5709 M5708 M5713

M5714 M5717 M5716 - General Permits GP327 M103-SL Although the route of the proposed Pipeline System will run approximately parallel to existing transmission lines (see Figure 3), it does not occupy the transmission line corridors. Hudbay is in discussions with Manitoba Hydro to ensure that all specifications for operation in proximity to a transmission line corridor are respected. A copy of this correspondence is included in Appendix B.

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1.6.3 Portion of the Project Site at or near Stall Concentrator/Anderson TIA

The end of the Pipeline System is at Stall Concentrator which overlies mineral interests held by Hudbay as follows: Mineral Lease

3416 -

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2. Project Information

2.1 Overview

Hudbay plans to increase production at Lalor Mine to its permitted level of 4,500 tonnes per day (tpd) from its current production rate of 3,500 tpd. Base metal ore will continue to be processed at Stall Concentrator using flotation to create copper and zinc concentrate. Gold bearing ore requires a cyanide leaching process to create gold and silver doré bars. The New Britannia Mill must be upgraded and refurbished to make it operational and capable of processing gold ore extracted from Lalor Mine. A pipeline corridor will be established linking the New Britannia Mill with Stall Concentrator/Anderson TIA. The corridor will contain three surface pipelines, running side by side, protected by an earthen cover to be constructed as part of this Project. One pipeline will direct tailings generated at the New Britannia Mill to the Stall Concentrator for ultimate deposit in Anderson TIA. A return water pipe will send water reclaimed from Anderson TIA to the New Britannia Mill via Stall Concentrator. The copper concentrate produced at Stall Concentrator will be pumped to New Britannia Mill via a third pipe. The project description presented in this section reflects the design changes and decision making with respect to alternatives described above in Section 1.5. These design changes and decisions are also discussed below in Section 5, which describes the results of the public engagement process which are cross-referenced with the results of the environmental assessment.

2.2 Regulatory Requirements

2.2.1 Manitoba

In addition to Manitoba Department of Sustainable Development Director’s approval of this NOA with respect to Environment Act Licence 1878 RR, Hudbay will require granting of Crown Land General Permit and Water Rights Licence applications described in Section 1.6 above. Hudbay will also require Crown Land Work Permits for construction activities such as clearing along the proposed Pipeline System route. As well, once the proposed Project has been constructed, Hudbay will file for the approval of the Director of Mines a revised Closure Plan and associated financial assurance in accordance with Sections 74 and 191 of the Mines and Minerals Act.

2.2.2 Federal

Based on a review of each of the components of the Project, no federal approval or environmental assessment is required. In terms of compliance with the Fisheries Act:

• There will be no new discharge of effluent to the environment and discharge out of Anderson TIA will continue to be required to comply with MDMER.

• Those components of the Project that are constructed adjacent to water frequented by fish are permitted to be and will be developed in accordance with Fisheries and Oceans Canada (DFO) “Measures to Avoid Causing Harm to Fish and Fish Habitat”.

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Section 17(b) of the Physical Activities Schedule to the Regulations Designating Physical Activities made under the Canadian Environmental Assessment Act, 2012 applies to the “expansion of an existing metal mill that would result in an increase in the area of mine operations of 50% or more and a total ore input capacity of 4,000 tpd or more.” Once it is operational, the New Britannia Mill will operate at approximately 1,500 tpd, which is within its original design capacity of 2,150 tpd.

2.2.3 Other Regulatory Restrictions

Restrictions on potential uses by others of the areas lying within or near the proposed route of the Pipeline System are imposed by the Town of Snow Lake Municipal By-law Number 733/94, Being a By-Law to Prevent the Use of Firearms and Bows and Arrows in Certain Areas, as amended by By-law Number 780/96. The entire route of the Pipeline System lies within an area in which the use of weapons is prohibited for the purpose of protecting human safety. The only persons exempt from this restriction would be Registered Trapline Holders, who are permitted to hunt.

2.3 Overview of Project Components

The Project has the following components:

• Refurbishment and improvement of the New Britannia Mill, comprised of the ore handling system, crushing operation, flotation and cyanide leaching system and supporting buildings and structures located on the New Britannia Mill site.

• The Pipeline System, comprised of a tailings pipe, return water pipe and copper concentrate pipe, leak detection and control systems and an access road with water crossing.

• The Auxiliary Components, which includes upgrades to or construction of supporting facilities such as ore stockpile pads, sound barriers, electrical transformers, New Britannia Mill truck access road, security and lighting.

The following boundaries are used in describing the project components and activities:

• Project Site – is comprised of the New Britannia Mill, Pipeline System and associated components, including the New Britannia freshwater pumphouse on the north shore of Snow Lake and freshwater pipeline to the New Britannia Mill.

• Project Area – is comprised of the an area that is 2 km beyond the Project Site, which is intended to take into account the effects of the Project (such as noise, vehicle emissions and traffic).

• Project Region – is comprised of an area that is up to 10 km beyond the Project Site, which is intended to take into account the maximum spatial extent of any potential impacts of the Project.

Figure 5 illustrates the project boundaries as described above.

2.4 New Britannia Mill Components

This section discusses the sub-components of the New Britannia Mill, describing them in the order in which ore will move through the various processes. Figure 6 shows the existing New Britannia Mill site. This section includes a description of the processes that will be carried out in existing features, any upgrades or changes to those existing features that will be required, and any new features that will be added as components of the Project. Figure 7 shows the proposed general arrangement for the refurbishment and improvement of the New Britannia Mill site.

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2.4.1 Ore Receiving and Handling System (New Feature)

Gold ore will be unloaded and stored briefly at a new ore pad (approximately 330 m2), as shown on Figure 7. The ore pad will be engineered to prevent metal leaching and ARD, building on design experience at other Hudbay facilities including Reed Mine.

2.4.2 Crushers (Upgrades/Replacements of Components in Existing Buildings)

From the ore pad, the ore will be unloaded to a new hopper that will be retrofitted onto the existing primary crusher building. The new hopper will be required because previously the New Britannia Mill was operated in association with the New Britannia Mine, with ore hoisted from underground directly into the primary crusher. Ore will be loaded into the hopper using a front end loader.

The existing crushers will be replaced with two new crushers located inside the existing crusher buildings (primary crusher and secondary crusher as shown on Figure 7. The new crushers will be equipped with wet scrubber dust collection systems.

The existing crusher buildings will be upgraded by installing additional soundproofing materials.

2.4.3 Mill Building (Upgrades/Replacements of Components inside Existing Buildings)

There will be no change to the external footprint of the existing mill building. An existing enclosed conveyer will convey crushed ore from the secondary crusher building to the existing enclosed fine ore bin. The fine ore bin dust collection system will be upgraded. The fine ore bin feeds into the mill via an existing conveyor house, all as shown on Figure 7. The mill building will be comprised of new and refurbished internal components (illustrated on Figure 7) and will include the following:

• Rod and ball mills (existing). • Cyclone (existing). • A leach feed thickener, pre-aeration tank, and three leach tanks (existing) located adjacent to

the mill building as shown in Figure 7. The new process will only need three of the four leach tanks. The fourth leach tank will be permanently decommissioned.

• Existing and refurbished process and fresh water tanks, chemical storage tanks, carbon in pulp (CIP) tanks, strip vessel, reactor, and refinery.

• Office, laboratories, control room, electrical room, maintenance shop, compressor room, change house, and laydown areas.

2.4.4 Flotation Building (New)

A new flotation step is essential for processing the ore blend (gold and base metal) from Lalor Mine. The process will produce a copper concentrate by removing copper from the ore which also will protect the leach circuit from the adverse effects of copper.

The new flotation circuit will be comprised of all new equipment housed in a new building immediately north of the existing mill building (illustrated in Figure 7). In the initial stages of design, the flotation building was to be situated between the existing mill building and the crusher, as shown on Slide 8 of the December 6, 2018 Public Information Session Presentation (attached in Appendix H). Because of the

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noise generated by the flotation process, the design at that stage also included a sound barrier along the southwestern boundary of the New Britannia Mill site. The design has now been improved to relocate the flotation building north of the Mill (as shown on Figure 7) and that sound barrier, which is no longer needed, has been removed from the design.

The total footprint of the new flotation building will be approximately 1,440 m2. The building will be approximately 16 m tall.

The equipment is:

• Seven copper rougher tanks and two flotation blowers. • Six copper concentrate cleaner tanks and pumps and two copper concentrate scavenger tanks

and pumps. • Copper concentrate thickener and filter. • Copper concentrate holding tank. • Reagent storage. • Copper concentrate storage shed. • Tailings pumps.

The flotation process is described in detail in Section 2.5. The flotation building will be connected to the mill building via a new utility corridor.

2.4.5 Lime Silo (New)

One 100-tonne storage silo will be constructed adjacent to the mill building (Figure 7) and be used to store pebbled quicklime (CaO). The silo will be equipped with a dust collector to minimize particulate emissions to the environment. Quicklime will be used to control pH throughout the production processes.

2.5 Production Processes

Figure 8 displays a flow diagram of each of the steps in the production processes and details the inputs and outputs at each stage of the process. The first step in processing ore is crushing. Ore will be crushed as described above in Section 2.4.2 to a particle size of 16 mm. The next step in ore processing is wet grinding in the existing circuit. The grinding process utilizes the rod mill and ball mill (described above in Section 2.4.3) in series to grind the ore and liberate the valuable minerals from the waste rock. Recycled water (Section 2.9.1 below describes the water source) is mixed in with the ore to create a slurry in the circuit. Once the ore reaches the target particle size (80 micron) it will be pumped to the new flotation building (described above in Section 2.4.4) for copper flotation. The copper flotation circuit will be comprised of a series of copper rougher, cleaners and scavenger flotation cells. These tanks will be aerated to promote the flotation of copper particles into a froth layer which is recovered from the top of the cells. The copper concentrate that is produced in this step will be thickened and filtered in the new thickener (described above in Section 2.4.4), stored in the copper concentrate storage shed, and eventually trucked to Flin Flon. From there, copper concentrate will be sent for distribution to the market.

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The tailings (i.e. everything that is not copper concentrate) that are left behind from the copper flotation circuit will be pumped back to the leach thickener located adjacent to the mill (Figure 7) as the start of the gold recovery process (cyanide leaching). In the leach thickener, the volume of water is reduced to increase the efficiency of the leach circuit. Thickener underflow (solids or pulp) will be pumped to the pre-aeration tank at the beginning of the cyanide leach circuit. Thickener overflow (water) will be pumped to the process water tank and recycled within the mill. The process of cyanide leaching involves adding sodium cyanide solution to the pulp to dissolve gold and silver minerals. One of the existing tanks will be used as the pre-aeration tank and three of the existing tanks will be used as leach tanks (described above in Section 2.4.3). Slaked lime will be added to the slurry to maintain the pH and prevent the formation of toxic hydrogen cyanide. It will take approximately 48 hours retention time to dissolve the gold and silver minerals into the cyanide leach solution. Once the minerals are dissolved, the solution will be pumped into a series of tanks for carbon in pulp (CIP) extraction. In this process, activated carbon is added to the tanks. Gold and silver adsorbs onto the surfaces of the carbon particles. The slurry discharge from the last CIP tank is pumped to a vibrating screen to recover the loaded carbon from the depleted slurry. The loaded carbon is washed with dilute hydrochloric acid to remove mineral scale (eg, calcium carbonate) and pumped to the elution vessel where the gold is stripped from the carbon with a hot caustic cyanide solution. The gold and silver bearing solution, referred to as “pregnant solution,” is then pumped to the electrowinning (EW) cell. In the EW cell, gold, silver and other metals (mainly iron) are deposited onto stainless steel cathodes. This deposit is periodically flushed from the cell as a sludge which is then filtered and dried. The dried sludge is then mixed with flux ingredients and smelted in a small induction furnace. The impure elements report to the slag which is recycled back to the grinding circuit. The final product from the furnace is an alloy of gold and silver referred to as doré. The doré bars will be shipped by a secure transportation company to a refinery for separation and refining into pure gold and silver. Tailings from the CIP circuit are pumped to the cyanide destruction (CND) tank. In this process, cyanide and cyanide complexes are oxidized to cyanate by the addition of sulphur dioxide and oxygen. The source of sulphur dioxide is sodium metabisulphite, which is added to the CND tank as a solution. Oxygen is provided by sparging compressed air into the slurry. Copper sulphate is added as needed to catalyze the reaction. The CND tank provides an hour of retention time to complete the reaction, after which the tailings pH is adjusted with lime and pumped to the tailings pipeline. Figure 8 provides an illustration of each of these steps and details the inputs and outputs at each stage of the process.

2.6 Auxiliary Components

The auxiliary components will include refurbishment or upgrade of existing facilities, as well as construction of new supporting facilities as follows:

• Construction of one sound barrier between the crushing operation and the Snow Lake Camp. Exact location and specifications will be determined during the detailed design phase (Note: there

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will be a sound barrier surrounding the east, north and western perimeter of the Snow Lake Camp).

• Replacement of an electrical transformer at the mill building and installation of a new transformer at the new flotation building. No additional powerlines or other new electrical infrastructure is required.

• Construction of three new control rooms: the main one located in the existing mill building (“main control room”), an operator station in the new flotation building (“flotation control room”) and an operator station in the crusher building (“crushing control room”). These control rooms will have access to all systems connected to the automation of the processes as well as alarms. The main control room will also have video surveillance of hard-to-reach instrumentation, spills and for security, safety and personnel accountability.

• Upgrading the fire alarm cable and annunciator systems. • Upgrading heat, lighting, and soundproofing in the existing buildings. • Installation of perimeter fencing and access gates. • Painting and coating of existing structures. • Roof repairs to existing buildings. • Adding a diesel generator to provide back-up power for tailings pumps. • Refurbishing the existing dry facility (change room with showers) within the existing buildings.

As part of the upgrades at the New Britannia Mill site, the existing access road located east of the Snow Lake Camp, will be upgraded to allow for haul truck access (Truck Access Road) from the New Britannia Mill site. The location of this Truck Access Road is shown in Figure 3. This access road will require a 10 m top of width driving surface to allow for two-way haul truck access. As there is already an existing road, approximately 0.37 ha of vegetation will need to be cleared to accommodate the upgraded new Truck Access Road. In areas near previously cleared right of ways (ROWs), small shrubs will be grubbed, levelled and spoiled, creating a small windrow along the route of the access road. A small amount of freshwater will be required for certain applications at the New Britannia Mill site. In order for freshwater to reach the site at the required flow velocity, the existing freshwater pipe from the water pumphouse at Snow Lake will be replaced. No new trenching will be required.

2.7 Pipeline System Components

The Pipeline System is comprised of the following:

• Tailings Pipe: Tailings will flow from New Britannia Mill to the Anderson TIA or the Lalor Paste Plant, via the Stall Concentrator.

• Return Water Pipe: Return water will flow from Anderson TIA to New Britannia Mill, via the Stall Concentrator.

• Copper Concentrate Pipe: Copper concentrate will flow from Stall Concentrator to New Britannia Mill.

• Access Road: Gravel access road will run along the entire length of the pipeline corridor for daily inspections and maintenance.

Hudbay retained Paterson & Cooke, an engineering firm which specializes in the design of tailings pipelines to design the Pipeline System. The design is similar to the Lalor Paste Plant tailings pipeline system, which operates in accordance with the Notice of Alteration to Environment Act Licence No. 3096 (approved January 30, 2017), and benefits from Hudbay’s experience in building and operating that system. The design provides for efficient flow to minimize the risk of blockages or failure of the pipes.

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The design builds in mitigation measures designed to prevent leaks and spillage into the environment and provide for easy maintenance. This Pipeline System will transect two road crossings via a conduit and the appropriate fill as per Section 2.7.6. Based upon the recommendations of Paterson & Cooke and the results of environmental field surveys (described below in Section 4), the route of the Pipeline System was selected to minimize impacts to wetlands and other sensitive environmental features. For the ease of describing the components, the Pipeline System is described in segments based on similar site conditions, special features and environmental conditions as shown in Figure 9. The segments are as follows:

• Segment 1 – within the Townsite of Snow Lake. • Segment 2 – Approximately parallel to Manitoba Hydro Transmission Line Right-of-Way

(ROW).

Details of these Segments are described below in Section 2.8.

2.7.1 Mitigation Measures built into Pipeline Design

The design of all three pipes features a leak detection system and emergency response system which will be effective in the unlikely event of a spill or malfunction as follows:

• All or most segments of the pipes will be thermal welded in order to eliminate opportunities for leaks to occur.

o The use of flanged or clamped sections will be minimized. • Leak detection along the length of the pipes will be provided by monitoring flow rates using

meters located near each end of the pipe. o A rupture in the pipe would result in a difference between the two flow rates, which will be

picked up through the mill control system. • Communication to the New Britannia Mill process control system will be provided by fibre optic

cable running the length of the Pipeline System. In the event of an alarm, site personnel will be dispatched to visually inspect the length of the pipeline to determine if there is a problem.

• The pipes will be double-walled as they cross Snow Creek and for approximately 500 m on either side of Snow Creek.

• The pipes will be covered with a sand berm to a depth of approximately 500 mm to minimize seasonal pipe expansion and contraction and to prevent the pipe from being breached in case of an accidental impact.

• Recycled water will be pumped through the pipe to prevent freezing during prolonged process outages.

• The pipes will be visually inspected daily by dedicated personnel. In addition to the above mitigation measures, the Tailings Pipe and the Copper Concentrate Pipe will be equipped with the following:

• Variable frequency drives will be installed on each pump to maintain a minimum flow velocity to prevent particle settling and plugging.

• The variable frequency drives will also be interlocked so that, in the unlikely event of a pressure change, the pumps will stop, providing an opportunity for dedicated personnel to check the cause of the pressure change and take action in case of a leak.

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2.7.2 Tailings Pipe

The Tailings Pipe will be comprised of an 8” high-density polyethylene (HDPE). As described above in Section 2.5, the tailings that remain following cyanide destruction will enter the tailings pipe through a new tailings pump box (approximately 3 m by 4 m) which will contain two trains of two slurry pumps operating in series. The Tailings Pipe will transport approximately 648,000 m3 of water and 470,000 tonnes of solids (in the form of tailings) annually.

2.7.3 Return Water Pipe

The Return Water Pipe will be comprised of a 6” HDPE pipe. This pipe will run parallel to the Tailings Pipe and will be sheltered under the same berm. The total water flow is estimated to be approximately 473,000 m3 annually. Most of the water flowing through the Return Water Pipe will be used to meet the process water requirements of the New Britannia Mill. A small portion of it will be used as dilution water in the Tailings Pipe to maintain the required minimum velocity.

2.7.4 Copper Concentrate Pipe

The Copper Concentrate Pipe will be comprised of a 3” HDPE pipe. This pipe will run parallel to the Tailings Pipe and Return Water Pipe and be sheltered under the same berm. Sending copper concentrate from Stall Concentrator to New Britannia has a number of advantages:

• The process at New Britannia is much more efficient at dewatering copper concentrate compared to the existing process at Stall Concentrator. Thus, the finished copper concentrate will contain less water, making transportation more efficient.

• It avoids the need to further upgrade Stall Concentrator. • Removing the copper thickening process from Stall Concentrator will improve Stall Concentrator’s

zinc thickening process. Thus, the synergistic relationship between the two facilities has an overall positive impact on the environment.

2.7.5 Fill Requirements

Once constructed, the pipes will be covered with sand along the entire route. Cover material will be required which will be obtained from a sand quarry or quarries located in the region. Fill requirements will be met from non-acid generating (NAG) sources (limestone or quarry) available in the region.

2.7.6 Freeze Protection

As described above in Section 2.7, the pipes will be buried under a sand berm to a depth of 500 mm and therefore will not need to be further insulated, with the exception of the Snow Creek and road crossings, which will be double-walled (described above in Section 2.7). During extended winter outages (e.g., maintenance shutdowns, power outages) a foam pig driven by compressed air will be used to drain the pipelines and provide freeze protection. During shorter outages, water will be circulated to prevent freezing.

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2.7.7 Pipeline System Road Crossings

There are two locations along the route of the Pipeline System at which the pipes will have to cross existing roads as shown in Figure 9. Road Crossing #1 is under a Manitoba Hydro substation access road which is currently used by Manitoba Hydro and also used by Hudbay to access the Birch Lake TDF. Road Crossing #2 is under PR 393 near the Stall Concentrator. Hudbay expects to enter into an agreement with Manitoba Infrastructure (MI) to permit the construction of these crossings in accordance with MI specifications. A copy of this agreement is included in Appendix B.

2.7.8 Modular Steel Bridge

An approximately 43 m long modular bridge designed to support the three pipes will be installed across Snow Creek as shown in Figure 9. This modular bridge will provide light vehicle access for daily inspections. This bridge also will be made available for use in emergencies if at any time the Snow Creek Bridge on PR 392 is inaccessible and ingress to or egress from the Town of Snow Lake is required. The abutments will include seven pre-cast concrete lock blocks per each abutment. These abutments will be installed above the high water mark. The final crossing location will be determined based on a geotechnical investigation and the final route confirmation.

2.7.9 Pipeline System Access Road

An unpaved access road will run parallel to the proposed Pipeline System and will consist of a single lane with turnarounds approximately every 250 m. The access road will be used for daily pipeline inspections, maintenance, and emergency access.

2.7.10 Clearing Requirements

Clearing will be completed utilizing mechanized equipment designed for tree removal. Trees will be mulched to as close as practical to the original ground elevation with tree stumps removed by an excavator. The mulched chips will be spread as is or spoiled along a narrow windrow along the route of the proposed Pipeline System. In areas near previously cleared ROWs, including roadways and the Manitoba Hydro ROW, small shrubs will be grubbed, levelled and spoiled, creating a small windrow along the route of the Pipeline System. Approximately 11.36 ha of forest will need to be cleared based on a 20 m ROW from the centreline of the Pipeline System. The area to be cleared and the tree cover type is described in detail in Section 6.7.1.1.

2.8 Route of the Pipeline System

The route of the Pipeline System will be approximately 6.8 km in length and will run parallel to the existing Manitoba Hydro ROW as shown in Figure 9. Hudbay is in discussions with Manitoba Hydro to ensure that all specifications for operation in proximity to a transmission line ROW are respected. A copy of this correspondence is included in Appendix B.

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The following general routing criteria were used to route the proposed Pipeline System:

• Following existing linear features to allow for gradual bends. • Avoiding and/or limiting water crossings, to the extent possible. • Avoiding rock outcrops to minimize the need for levelling and the use of explosives. • Using cleared ROW, where available, to minimize clearing requirements.

An additional consideration was that the ROW containing the Pipeline System must be wide enough to accommodate vehicle access needed for regular inspection. The proposed route is outlined in the sections below.

2.8.1 Segment 1 (within the Townsite of Snow Lake)

Figure 10 displays Segment 1 of the proposed Pipeline System route. Segment 1 of the route travels from the existing New Britannia Mill building north towards an existing access road, then turns east around the Province of Manitoba Arsenopyrite Stockpile and Province of Manitoba remediated Former Tailings Area, and then turns south towards the Manitoba Hydro ROW. Segment 1 of the route is already occupied by Hudbay infrastructure or other developed uses.

2.8.2 Segment 2 (Approximately Parallel to Hydro ROW)

Figure 11 displays Segment 2 of the proposed Pipeline System route. Segment 2 travels approximately 5.6 km parallel to Manitoba Hydro ROW to the north (along HS15), then turns south and runs along the Manitoba Hydro ROW to the south (along P18H) to the Stall Concentrator. Beginning in Segment 2, the access road will be designed to include intermittent 10 m wide points for turnaround bays. These bays will occur at an average of approximately 250 m intervals. The exact location of the turnaround bays will be determined in the detailed design phase of the Project, avoiding such features as bedrock, outcrops, marsh/bogs and water crossings.

2.9 Production Capacity

Once operational, the New Britannia Mill will have a production capacity of 1,500 tpd.

2.9.1 Water Requirements

The water requirements for the New Britannia Mill are indicated in the mass balance diagram contained in Figure 12.

2.9.1.1 Process Water

The process water system will be designed to minimize the use of fresh water to the greatest extent possible by using water from Anderson TIA internally within the mill building. Water that is recycled from different processes (i.e. tailings thickening, discussed above in Section 2.5) will also be stored in a tank on site and reused within the mill building. Approximately 90% of the water used in the New Britannia Mill operation will be recycled water drawn from Anderson TIA.

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2.9.1.2 Freshwater

A small amount of freshwater (approximately 10%) will be required for certain applications (such as reagent mixing, fire suppression, and seal water for pumps) for which the quality of process water or recycled water is not adequate. This freshwater will be supplied from the existing fresh water pump house at Snow Lake. As discussed in Section 2.6, the existing freshwater pipe from the Snow Lake pumphouse to the New Britannia Mill site will be replaced in order for the freshwater to be received at the site at the required flow velocity.

2.9.2 Air

Three (3) air systems will be required:

• Air for the flotation tanks will be provided by low pressure blowers (50 kPa) located within the Flotation Building.

• Air for leaching and cyanide destruction will be provided by a compressor (310 kPa) located within the mill building.

• Air for instruments within the mill building will be provided by a compressor (700 kPa).

2.9.3 Employees

Once operational, the New Britannia Mill will employ approximately 65 people full-time. It is anticipated that some or all of these jobs will become available as employment in the Flin Flon operations decreases. Sub-contractors may be hired as required to carry out specialized maintenance activities.

2.9.4 Mill Materials

New Britannia Mill will utilize reagents that are commonly used throughout the mining industry. Table 2-1 provides a summary of consumption requirements, while specific functions of these materials, addition rates, and dispositions are provided in the sections that follow.

Table 2-1: Summary of Reagents and Additives Required for New Britannia Mill

Reagent Material Quantity Required (tonnes per year)

Delivery Storage Considerations Area Used and Purpose

Flocculant

kg/t milled 0.035 20 kg bags The flocculant reagent area will be contained and raised, with slip

resistant flooring in the preparation area.

Concentrate and tailings thickening: promotes

settling of solids t/yr 10.1

Methyl Isobutyl Carbinol (MIBC)

kg/t milled 0.03 Barrel or 1,000 kg totes

MIBC is an alcohol therefore the storage

area requires access to fire suppression.

Flotation: frother t/yr 8.7

Cytec 3418A kg/t milled 0.015 1,000 kg totes None. Flotation: sulphide

collector t/yr 4.34

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Depramin 347 (Carboxy Methyl

Cellulose)

kg/t milled 0.45 1,000 kg totes None. Flotation: gangue depressant

t/yr 130

Copper Sulphate kg/t milled 0.009 1,000 kg totes None. Cyanide destruction:

catalyzes oxidation reaction

t/yr 2.6

Lime

kg/t milled 1.76 Bulk, pebbled lime

Lime is a basic solution therefore the storage

area requires containment in a raised

holding tank. Will be stored in a lime silo.

Cyanide leaching circuit: pH control t/yr 510

Sodium Cyanide

kg/t milled 0.731 1,000 kg totes, briquettes by a

licensed supplier

As described above in Section 1.1.2, storage

and transport will comply with the cyanide code.

Cyanide will be stored in a tank with secondary

containment.

Cyanide leaching circuit: dissolution of gold and

silver t/yr 212

Lead Nitrate kg/t milled 0.047 1,000 kg totes None. Cyanide leaching circuit:

inhibits oxidation of pyrrhotite

t/yr 13.6

Carbon kg/t milled 0.01 500 kg bags None. Carbon Adsorption:

recover gold from solution t/yr 2.9

Sodium Metabisulphite

kg/t milled 1.47 1,000 kg totes None. Cyanide destruction: used with air for oxidation of

cyanide t/yr 426

Sodium Hydroxide

kg/t milled 0.019 20 kg bags Caustic material, stored with secondary containment.

Carbon Elution: pH control t/yr 5.50

Hydrochloric Acid

kg/t milled 0.015 1,000 kg totes

Acidic material, stored with secondary containment.

Carbon washing: removes foulants from carbon

t/yr 4.3

Antiscalant kg/t milled 0.002 Barrels, liquid None. Process water system:

prevents scaling of lines t/yr 0.6

Borax kg/t milled 0.0021 20 kg bags or

pails None. Refining: flux component

t/yr 0.61

Sodium Nitrate kg/t milled 0.0012 20 kg bags or


t/yr 0.35

Sodium Carbonate

kg/t milled 0.0003 20 kg bags or pails

None. Refining: flux component t/yr 0.09

Silica Sand kg/t milled 0

.0014 20 kg bags or


t/yr 0.41

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Ferric Sulphate kg/t milled 0.15 Bulk solution,

trucks None. Final effluent treatment:

arsenic removal t/yr 43,440

Propane kg/yr 2,000 Bulk Flammable. Grinding area: unit

heaters

2.10 Equipment Use

Table 2-2 and Table 2-3 present the equipment use expected during construction of the Project.

Table 2-2: Equipment Use during Construction of the Mill

Equipment Units Duration of Use Forklift 1 8 months Zoom Boom 1 8 months 50t Crane 1 4 months 100t Crane 1 2 months JLG® Manlift 2 5 months Welders 2 3 months Light Stands 3 3 months Construction Crew/Supervisor Trucks 3 8 months Front End Loader 1 6 months Bobcat 1 8 months Caterpillar Dozer 1 3 months Generator 1 6 months Construction Heaters 3 2 months Excavator 1 4 months Dump Trucks 3 4 months

Source: Information provided by Hudbay.

Table 2-3: Equipment Use during Construction of the Pipeline System

Equipment Units Duration of Use

Front-end Loader 2 4 months Rock Trucks 10 4 months Tracked Excavator 2 4 months

Dozer 2 4 months Fusion Welding Machine 1 4 months Pickup Trucks 5 4 months Hydro-Axe/Brush Clearing Equipment 2 4 months


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2.10.1 Solid and Hazardous Waste

All domestic and non-hazardous waste generated at the mill will be disposed of at licensed waste disposal facilities. Hudbay will make arrangements with a licensed hazardous waste handler with respect to any hazardous wastes produced (e.g., used oil, oily rags, chemical delivery containers, etc.).

2.11 Traffic

Table 2-4 presents the estimated daily traffic volumes expected during operation of the proposed Project. A detailed traffic study was conducted to determine the impact on the Town of Snow Lake. The study results are presented in the Traffic Impacts Evaluation report attached as Appendix C.

Table 2-4: Estimated Daily Traffic Volumes during Operation

Vehicle Type Anticipated Traffic Volume (per day)

Loaded ore trucks from Lalor 45 Empty ore trucks leaving New Britannia Mill 45 Copper concentrate to Flin Flon 3 Delivery trucks 6


2.12 Emissions, Discharges and Waste

2.12.1 Atmospheric Emissions

Atmospheric emissions associated with the Project will be greenhouse gases, dust and particular matter and exhaust emissions, which is typical of industrial activity. Noise will also be generated through various activities during construction and operation of the mill.

2.12.1.1 Dust and Particulate Matter

Sources of dust include activities such as crushing, unloading ore at the New Britannia site, movement of traffic on roads and access roads for pipeline inspections, maintenance and emergency response. Dust occurs primarily during summer and fall, with greater likelihood for an increase in dust during dry and windy conditions. An air quality assessment was completed to predict the potential impact of air emissions on nearby receptors. Additional details regarding the assessment are provided in the Air Quality Dispersion Modelling Report attached as Appendix D.

2.12.1.2 Noise

The primary sources of noise associated with the Project construction include the installation of a new floatation building and pipeline infrastructure for transporting tailings to Anderson TIA and copper concentrate to the Stall Concentrator. During operation, examples of primary sources of noise include ore crushers, conveyors, delivery trucks, other mobile equipment and supporting HVAC equipment at the New Britannia Mill site.

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A noise assessment was completed to predict the potential noise impact on nearby sensitive points of reception at the mill. The noise impact was determined based on comparing the predicted sound levels at the points of reception with guidance provided by either Health Canada or the Province of Manitoba noise guidelines. The results of the predictive models indicated that with the application of some noise mitigation measures, the New Britannia Mill site can be constructed and operated in compliance with the guidance sound level limits. Additional details regarding the assessment of noise effects are provided in the Noise Impact Assessment in Appendix E.

2.13 Continued Use of Existing Approved Facilities

2.13.1 Sewage

The New Britannia Mill has a holding tank for sewage, operated in accordance with the Manitoba Onsite Wastewater Management Systems Regulation. The sewage is pumped out and trucked to the Town of Snow Lake municipal sewage treatment plant for disposal. The existing office building, which will continue to be used, is serviced by the Town of Snow Lake municipal sewer system.

2.13.2 Anderson TIA

The Anderson TIA has been used for sub-aqueous disposal of tailings since commissioning of the Stall Concentrator in 1979. It operated, and continues to operate in accordance with the Metal Mining Effluents Regulation (now amended and re-named the Metal and Diamond Mining Effluent Regulations (MDMER)). The Anderson TIA was authorized originally by Manitoba Clean Environment Commission (CEC) Order No. 766 until receiving a new Environment Act Licence on June 20, 2018 (Environment Act Licence No. 3263). As noted above in Section 1.4.2, the new licence authorizes expansion of Anderson TIA in contemplation of the full volume of tailings that might be generated in processing ore from the Lalor deposits, including both base metal and gold zones.

2.13.3 Stall Concentrator

The Stall Concentrator was commissioned at the same time as the Anderson TIA and has been in continuous operation since then, with the exception of brief periods during 1993-1994, 1999 and 2009. Stall Concentrator is currently used to process ore from Lalor Mine, producing copper and zinc concentrate, which is then shipped to Flin Flon for further processing.

2.13.4 Use of Other Existing Facilities

Additional existing facilities that will be used during the construction and operation of the proposed Project are:

• Hudbay’s Snow Lake Camp. • Pumphouse on the north shore of Snow Lake.

The location of these facilities are shown on Figure 3.

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2.14 Project Phases and Proposed Schedule

Construction at the New Britannia site is anticipated to begin in the fourth quarter of 2019, once all necessary approvals have been received. Construction activities are:

• Bringing materials and equipment to site (excavating, hauling, stockpiling, storing fuels). • Constructing flotation building, ore receiving area, upgrades within existing mill (erecting

buildings, installing equipment, grading and backfilling). • Preparing the Pipeline System ROW (clearing vegetation, stripping topsoil, excavating). • Installing the Pipeline System (laying pipes, grading, compacting).

It is anticipated that construction will be completed within one year of commencement. The timing of certain construction activities will be subject to seasonal restrictions, based upon climate conditions and environmental concerns (e.g., migratory bird nesting and DFO constraints) (discussed below in Section 6).

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3. Scope of the Assessment

To assess the potential environmental effects of the proposed Project, spatial and temporal boundaries were defined as follows:

3.1 Temporal Boundaries

The temporal boundaries of the assessment are divided as follows:

• Construction Phase: Construction from the fourth quarter of 2019 through to fourth quarter of 2020 (approximately 12 months).

• Operation Phase: First quarter of 2021 to 2027. • Closure Phase: 2027-2030, depending on the time it takes for re-vegetation.

3.2 Spatial Boundaries

Spatial boundaries used for the assessment are described below:

• Project Site – is comprised of the New Britannia Mill, Pipeline System and associated components.

• Project Area – is comprised of an area that is 2 km beyond the Project Site, which is intended to take into account the effects of the Project (such as noise, vehicle emissions and traffic).

• Project Region – is comprised of an area that is up to 10 km beyond the Project Site, which is intended to take into account the maximum spatial extent of any potential impacts of the Project.

Figure 5 shows the Project Site, Project Area and Project Region.

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4. Environmental Setting

This section provides an overview of the physical, aquatic and terrestrial environment in the Project Area and Region.

4.1 Sources of Information

The information presented herein was obtained either through literature searches of publicly available datasets or through environmental baseline studies carried out by AECOM on behalf of Hudbay in 2018. The baseline investigations carried out in 2007, 2008, 2010, 2011, 2012, 2013, 2014, and 2015 are reported on in the Proposed Lalor Mine Environmental Baseline Assessment (AECOM, 2012a), which was filed with the Lalor Mine Environment Act Proposal (EAP) (AECOM, 2012b), the Proposed Lalor Concentrator Environmental Baseline Assessment, which was filed with the Lalor Concentrator EAP (subsequently withdrawn), and the information filed with the Anderson Tailings Impoundment Area, Notice of Alteration (AECOM, 2016). These reports are the basis for the information summarized in the sections below. The majority of the descriptions of the physical, aquatic, and terrestrial environments within the Project Area and Region are based on the results of the investigations conducted in the area in spring and fall of 2018.

4.2 Environmental Assessment Team

In June 2018 and October 2018, AECOM and two traditional knowledge holders (a member of the Manitoba Metis from the Town of Snow Lake and a member of Mathias Colomb Cree Nation) carried out terrestrial and aquatic surveys in the Project Site, Area, and Region (the environmental assessment team is introduced in detail in the public presentation materials included in Appendix H).

4.3 Environmental and Social Components

This environmental assessment considers changes to the environment that may be caused by the proposed Project, as well as any consequential socio-economic implications. The environmental components (ECs) and social components (SCs) were selected following the guidance provided Sustainable Development’s Information Bulletin, "Environment Act Proposal Report Guidelines” and “Alterations to Developments with Environment Act Licences.” SCs include components of the socio-economic environment that may be affected by a change in the environment caused by the proposed alteration. The potential interactions between Project components and ECs and SCs are identified in Section 6. Potential interactions were identified by the assessment team, applying professional judgement and experience. The sections below identify where environmental assessment conclusions are based on the knowledge and professional judgement of traditional knowledge holders. In forming conclusions and recommendations, the assessment team took into account that Hudbay would implement standard environmentally responsible construction techniques and operating procedures in the course of construction, operation and closure of the proposed alteration.

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The potential interactions identified in Table 4-1 and the results of the assessment are stated in Section 6. Section 6 also contains a summary table of all mitigation measures, including those built in to the design and those recommended by the environmental assessment team. The predicted residual effects also are described in Section 6.

Hudbay Minerals Inc.Notice of AlerationNew Britannia Mill

AquaticEnvironment

Topo

grap

hy

Soi

l

Gro

undw

ater

Sur

face

Wat

er a

ndD

rain

age

Veg

etat

ion

Wild

life

Air

Qua

lity

Noi

se a

nd V

ibra

tion

Clim

ate

Aqu

atic

Res

ourc

es

Land

and

Res

ourc

eU

se

Her

itage

Res

ourc

es

Tran

spor

tatio

n

Aes

thet

ics

Transportation of equipment and materials to the Project Site X X X X X X X X X

Stockpiling of equipment and materials at the Project Site X X X X X X X X X

Additional land preparation (including clearing vegetation, stripping topsoil, etc.) X X X X X X X X X X X

Installing equipment and buildings at the New Britannia Mill X X X X X X X X X X

Installing Pipeline System (laying pipes, grading, compacting, installing) X X X X X X X X X X X

Waste disposal X X X X X X

Site restoration X X X X

Ore receiving and handling system X X X

Milling X X

Copper flotation X

Material transported via the Pipeline System

Maintaining Pipeline System X X X X

Removing infrastructure at the New Britannia Mill site X X X X X X X

Removing Pipeline System and associated infrastructure X X X X X X X X X

Scarifying Pipeline System ROW X X X X X X X X X X

Testing, removing, and remediating any contaminated soils X X X X X X X X X

Re-grading and contouring X X X X

Re-vegetating disturbed areas X X X X X

Notes:X = identified interaction

Table 4-1: Identification of Potential Environmental/Social Component Interactions with the Project

1. only indirect interactions with SCs as a result of an direct project/EC interactions were considered

Operation Phase

Construction Phase

Socio-Economic EnvironmentTerrestrial Environment Atmospheric Environment

Closure Phase

Physical Environment

32

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4.4 Physical Environment

The physiographic setting of the Project Region is defined using the ecological land classification system. This hierarchical system of ecozones, ecoregions and ecodistricts represents subdivisions of increasing ecological detail. The Project Site is located within the:

• Boreal Shield Ecozone, which contains the; • Churchill River Upland Ecoregion, which contains the; • Reed Lake Ecodistrict and Wekusko Ecodistrict.

The Boreal Shield Ecozone, the largest ecozone in Canada, extends from northern Saskatchewan east to Newfoundland, north and east of Lake Winnipeg and finally north of the Great Lakes and St. Lawrence River. The Churchill River Upland Ecoregion extends from the sparsely forested regions to the north, the southern edge of the Precambrian Shield to the south and extends westward from the Grass River to the Saskatchewan border. The Reed Lake Ecodistrict extends west from Wekusko Lake to just over the Saskatchewan border and the Wekusko Ecodistrict includes Wekusko Lake north towards Burntwood Lake as shown in Figure 13.

4.4.1 Topography

The Project Region is characterized by broken, hilly to rolling bedrock, which controls relief of the area. The bedrock is partially covered by unconsolidated mineral and organic materials. Elevations within the Project Region vary from more than 312 meters above sea level (masl) for the highest bedrock outcrops to the west to approximately 256 masl near Wekusko Lake, located to the east (Department of Energy, Mines and Resources, 1985 and 1995). The elevations in the Reed Lake Ecodistrict and Wekusko Ecodistrict range from approximately 255 metres above sea level (masl) to 335 masl. Slope lengths in the Ecodistrict range from approximately less than 50 m to more than 150 m in length. Rocky cliffs can rise from 25 m to 40 m above the lakes and peat-filled depressions (Smith, et al., 1998). During the 2018 surveys, the following topographic features were observed:

• Segment 1, located mainly in the Townsite of Snow Lake, is relatively flat with compacted gravel around existing infrastructure.

• The Province of Manitoba Arsenopyrite Residue Stockpile berm is approximately 1 m to 2 m high and surrounded by a wetland area on the northeastern and eastern edges.

• There are several areas of steep rock outcrop, within Segment 2, north of the existing Manitoba Hydro transmission line HS15 as shown in Figure 11.

4.4.2 Geology

The Project Region is part of the Flin Flon Belt (FFB), which according to the Manitoba Geological Survey, is in the juvenile internal zone of the Trans-Hudson Orogen and consists of Paleoproterozoic volcanic, plutonic and minor sedimentary rocks. According to Manitoba’s Mineral Resources Geological Survey, “the Flin Flon greenstone belt extends hundreds of kilometres to the south-southwest beneath a thin, geophysically transparent Phanerozoic cover. To the north the FFB is tectonically overthrust by younger metasedimentary rocks of the Kisseynew domain and by nappes of metavolcanic rocks that are the same age as those in the FFB.” (Government of Manitoba, 2017).

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The tectonostratigraphic architecture of the FFB is of vital economic significance. The FFB is one of the largest Proterozoic volcanic-hosted massive sulphide (VMS) districts in the world, containing 27 copper – zinc (gold) deposits. Of these deposits, more than 162 M tonnes of sulphide have already been mined (Bailes and Galley, 1999).

4.4.3 Soil

As noted above, the Reed Lake Ecodistrict extends west from Wekusko Lake to just over the Saskatchewan border and the Wekusko Ecodistrict includes Wekusko Lake north towards Burntwood Lake. Acidic granitoid bedrock in the form of sloping uplands and lowlands can be found in these ecodistricts. Bedrock areas are subdominant and widely distributed areas of permafrost can occur in peatlands. Dystric Brunisols are the dominant soils in these ecodistricts. These soils have developed over glacial till overlying bedrock and consist of shallow, sandy and stoney veneers. Peat-filled depressions with very poorly drained Typic and Terric Fibrisolic and Mesisolic Organic soils can be found throughout these ecodistricts. These soils are overly loamy to clayey glaciolacustrine sediments. Eutric Brunisols and Gray Luvisols can be found on sandy bars, beaches and exposed clayey deposits (Smith, et al., 1998).

4.4.4 Groundwater

Although there is no existing comprehensive regional study describing the groundwater flow system, based on conditions in similar environments, the regional shallow groundwater flow, in particular in the overburden, is likely controlled by the topography and bedrock surface in and around the Project Region. Shallow groundwater flow will generally follow the topography and drain to the low-lying areas where it will discharge to surface waterbodies and wetlands. Shallow groundwater tables are high in most peat lands and at or near the bedrock surface in low areas bordering the peat lands. Shallow groundwater levels in the area are generally at or near surface in the spring and early summer and drop as the year progresses. Recharge of shallow groundwater can be expected to occur in elevated areas. The hydraulic conductivity of unfractured crystalline igneous and metamorphic rocks is typically very low and most groundwater movement occurs through secondary permeability features consisting of joints, shears, or faults. The distribution of these features in the subsurface is very difficult to predict and large variations in the frequency of secondary features should be expected on both a local and a regional scale. The permeability of individual features may also show marked variations over short distances and the frequency and permeability of fractures decline with depth. The zone of active groundwater circulation is generally confined to the upper 60 to 150 m of bedrock where joints are more common and tend to be more open yet significant zones of secondary permeability may persist to depth. Since the region possesses an abundance of surface water resources, the demand for groundwater is low and little is known about the distribution of aquifers, their yield or water quality. However, the Manitoba Sustainable Development water well records indicate that there is some groundwater utilization within the Project Region. There are 22 registered groundwater wells in use within the Project Region (Manitoba Water Stewardship, 2012). These are located within the property development around Wekusko Lake (Taylor Bay, Berry Bay and along PR 392), the Town of Snow Lake and Wekusko Falls Provincial Park. Bedrock groundwater wells, if present, are likely connected to fractures or discontinuities that are connected to the local water table and are not likely regionally interconnected.

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4.4.5 Surface Water and Drainage

As noted above, the Project Area straddles the Reed Lake Ecodistrict and the Wekusko Ecodistrict, which both lie within the glacial Lake Agassiz basin. These Ecodistricts are contained within the Nelson River drainage system (Smith, et al., 1998). As shown on Figure 14, the Project Area drains generally eastward through Wekusko Lake, other medium sized lakes in the general region and an irregular bedrock-controlled network of streams that are all part of the Grassy River watershed. Snow Lake and Snow Creek are located within the Project Area. The Pipeline System crosses Snow Creek which flows from Snow Lake east/southeast into Wekusko Lake located approximately 12 km downstream of Snow Lake (Figure 2 and Figure 9). The Tailings Pipeline will pump tailings from the New Britannia Mill to the Anderson TIA. The downstream receptor for the Anderson TIA is Anderson Bay of Wekusko Lake (see Figure 2). The Anderson TIA drains to Anderson Creek, which is almost entirely fed from the Anderson TIA discharge pipe, with a smaller amount of water coming from the Anderson TIA spillway and surface drainage. Anderson Creek crosses PR 392 and meanders for approximately 1.25 km before merging with Stall Creek and entering Anderson Bay of Wekusko Lake. Stall Creek and Anderson Creek merge approximately 0.2 km from the confluence with Anderson Bay, meandering through a wide wetland area dominated by emergent macrophytes. Due to varying topography created by hummocky bedrock surfaces, the drainage conditions vary considerably over short distances. Regionally the terrain falls at about 0.6 m to 1.0 m per km and runoff from bedrock and upland areas collects in peat-filled lows (bogs), which slowly release excess water to surrounding lakes and creeks. Groundwater tables are high in most bogs and in low areas bordering the bogs (Smith et al., 1998). Similar to much of the Boreal Shield Ecozone, contiguous and isolated bogs cover between 20% and 40% of the Project Region. Bogs are widespread and stagnant in the Project Region.

4.5 Atmospheric Environment

4.5.1 Air Quality

Although specific measurements of air quality in the Project Region are not available, air quality in this area is considered very good compared with larger cities and commercial and industrial areas in Manitoba. There are no industrial operations with a significant release of air emissions within the Project Region. The closest industrial activities are in the City of Flin Flon and the Town of The Pas, located approximately 120 km and 140 km west of the Project Site, respectively. Occasional regional impediments to air quality, although uncommon, may occur in the Project Region. This could include smoke from forest fires and wood-burning stoves, emissions from fuel storage tanks, dust from gravel roads, and vehicle emissions. AECOM completed an Air Quality Dispersion Modelling Report as part of this assessment and it is included as Appendix D.

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4.5.2 Noise and Vibration

A baseline noise assessment was undertaken by AECOM in the Snow Lake region in July, 2011 (AECOM, 2012). During this study, noise baseline data was collected at two Points of Reception (POR) within the Town of Snow Lake. The measured background levels were determined to be typical of a suburban area where the dominant sources of ambient noise and vibration are vehicular traffic. The equivalent day/night sound levels were calculated to be 53 dBA at POR 1 and 49 dBA at POR 2. Average root mean square velocities ranged from 0.045 to 0.426 mm/s at POR 1 and POR 2 over a 24 hour period. AECOM completed a Noise Impact Assessment as part of this assessment and it is included in Appendix E.

4.5.3 Climate

The closest weather station to the site is near Baker’s Narrows at the Flin Flon airport, approximately 100 km west of the Project Site. The Flin Flon airport is located at an elevation of 304 masl and in our opinion is climatically representative of the Project Site. The mean annual air temperature at the Flin Flon airport is -0.2°C. The daily mean temperature ranges between 18°C in July and -21°C in January. Total annual precipitation at the Flin Flon airport is composed of 339 mm of rain and 141 cm of snow. July has the highest average rainfall (77 mm), whereas November has the highest average snowfall (25 cm) (Environment Canada, 2018). The average temperature, precipitation, and wind conditions measured at the Flin Flon airport each month are provided in Table 4-2.

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Table 4-2: Climate Data for the Flin Flon Airport, Manitoba (1981-2010)

Parameter

Month

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Year

Cod

e

Temperature (°C)

Daily Average

-19.8 -16.2 -8.9 0.8 8.4 14.9 18.2 17 10.4 2.6 -8.4 -17.1 0.2 A

Daily Maximum

-15.1 -10.8 -2.7 6.9 14.4 20.4 23.4 22 14.7 6 -5.1 -12.9 5.1 A

Daily Minimum

-24.5 -21.5 -15 -5.3 2.3 9.5 13 12 6.1 -0.9 -11.6 -21.3 -4.8 A

Precipitation

Rainfall (mm)

0.2 0.3 1.4 10.3 37.3 67.2 83.1 67.2 62.5 23.6 1.4 0.5 354.9 A

Snowfall (cm)

21.7 18.2 19.7 18.7 3.6 0 0 0 1.7 14.6 27.5 24.6 150.2 A

Wind Conditions

(km/h)

Speed 9.1 9.9 9.9 10.8 10.8 11.2 10.6 10.6 12 12 10.9 9.3 10.6 D

Most Frequent Direction

NW N S S S S S S S N N N S D

Notes: Data obtained from Flin Flon A meteorological station, latitude 54⁰ 41’ N longitude 101⁰ 41’ W Elevation 303.90 m (Environment Canada, 2018). "A": World Meteorological Organization “3 and 5 rule” (i.e., no more than 3 consecutive and no more than 5 total missing for either temperature or precipitation). “D”: At least 15 years.

4.6 Terrestrial Environment

4.6.1 Scope of Terrestrial Assessment

The New Britannia Mill site is a wholly developed operational site, which has been an active mining operation since 1948. Similarly, the end of the Pipeline System is within an active area that is occupied by Hudbay’s Stall Concentrator. The terrestrial assessment therefore focused on those portions of the proposed pipeline route which connect the two developed areas.

4.6.2 Methods

During spring and fall of 2018, the study team ground-truthed (walked and observed) the entire length of the proposed Pipeline System route, with the exception of the southern portion of Segment 2 along Manitoba Hydro Corridor P18H. Based on extensive experience in the Project Region and professional judgement, the terrestrial environment along the southern portion of Segment 2 is likely similar to the portion of Segment 2 that lies along Manitoba Hydro Corridor HS15, which was ground-truthed during the 2018 survey. However, a follow-up terrestrial survey is planned for spring 2019 to ground-truth the balance of the route.

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4.6.3 Vegetation

Vegetation in the Reed Lake Ecodistrict and Wekusko Ecodistrict is typical of the northern Boreal forest region with black spruce (Picea mariana), jack pine (Pinus banksiana), trembling leaf aspen (Populus tremuloides) and white spruce (Picea glauca). The bog peat-lands have stunted Black Spruce, moss, and ericaceous shrub vegetation, while fens have sedge (Carex sp.), shrub and tamarack (Larix laricina) in varying mixtures. Forest composition is reflective of a forest fire history (Smith et al., 1998). Overall, the Project Region is naturally a dense boreal forest, primarily Black Spruce interspersed with jack pine and hardwoods. Dense forest canopy has limited understory growth in all areas within the Project Region. Sphagnum forms the dominant ground cover. During the 2018 ground-truthing, the following vegetative features were observed:

• Vegetative communities encountered in Segment 2 are common to the Reed Lake and Wekusko Lake Ecodistricts. No unique habitats were observed. Representative photographs of the vegetation in Segment 2 along Manitoba Hydro transmission line HS15 are provided in Figure 11.

• The most sensitive flora community along the proposed Pipeline System route consisted of a cattail marsh measuring approximately 0.8 ha, located south of the Birch Lake TDF and west of Manitoba Hydro transmission line HS15, as illustrated in Figure 10.

• An abundance of deadfall was observed within Segment 2 including in Snow Creek. • The traditional knowledge holder in the Study Team noticed medicinal plants growing within a

wetland area at the northwest edge of Segment 1, adjacent to the existing tailings berm. The species identification of the medicinal plants could not be determined due to the plant being in in a state of senescence. However, the plant was recognized by the Indigenous Elder as being of medicinal importance. See Section 6.7.1 below, where it is noted that these are medicinal plants common to wetland areas but that this area will be avoided in the final design of the route.

Representative photographs of the vegetation in Segment 1 and Segment 2 are provided in Figure 10 and Figures 11, respectively. Plant ‘Species at Risk2’ that may occur in the Churchill River Upland Ecoregion within which the Project Site occurs, include the listed species in Table 4-3. No plant Species at Risk or habitat potentially supporting plant Species at Risk were observed during reconnaissance investigations of the Project Site in June 2018.

4.6.4 Wildlife

The Churchill River Upland Ecoregion provides habitat for moose (Alces alces), boreal woodland caribou (Rangifer tarandus caribou), black bear (Ursus americanus), lynx (Lynx lynx), timber wolf (Canis lupus), beaver (Castor canadensis), muskrat (Ondatra zibethicus) and snowshoe hare (Lepus americanus). Various bird species including sandhill crane (Grus canadensis), grouse, waterfowl (i.e., ducks, geese and pelicans) along with many other birds are found in this ecoregion (Smith et al., 1998). During the field studies conducted between the years 2007 and 2012 in the Project Region, signs of black bear and moose in the Project Region were apparent. Wildlife directly observed included waterfowl, 2 ‘Species at Risk’ are defined for the purposed of this report as those species listed in The Endangered Species and Ecosystems

Act of Manitoba (MBESEA) and/or those listed as ‘Endangered’ or ‘Threatened’ in Schedule 1 of the federal Species at Risk Act (SARA).

http://web2.gov.mb.ca/laws/statutes/ccsm/e111e.php

http://web2.gov.mb.ca/laws/statutes/ccsm/e111e.php

http://laws-lois.justice.gc.ca/eng/acts/s-15.3/

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common raven, coyote, red fox, whitetail deer, timber wolf, river otter, beaver, eagles, American white pelican, cranes, loons, and frogs. (AECOM, 2016) During the 2018 ground-truthing, the following evidence of wildlife and habitat was observed:

• Wildlife populations have open access to a large area of natural woodland in the region that provides river and lakeshore edge habitat and many burned areas in various stages of re-growth. The proposed route of the pipeline, like the broad area surrounding it in the Project Area and Region, provides a large diversity of habitats that favour wildlife populations.

• Wildlife species can make use of the Project Area to the extent that it benefits them, but are not restricted to it. There is no limitation on the ability of wildlife species to migrate into more favourable areas within the general region.

• Evidence of moose activity was observed in the Project Area. Moose scat, prints, along with a cow and calf bedding site were observed north of the intersection of PR 392 and PR 395, south of the existing Manitoba Hydro transmission line (HS15). The location of these sightings is shown on Figure 11.

• During the aquatic survey, a lone female moose was encountered in Snow Creek, east of PR 392 and west of the Manitoba Hydro transmission line (HS15).

• Otter, moose and bear trails were observed along the proposed pipeline route in Segment 2 along the Manitoba Hydro transmission line (HS15), as shown in Figure 11.

4.7 Protected Species

To identify species at risk that may occur in the Project Region, a variety of online databases were examined including the Department of Sustainable Development, Manitoba Conservation Data Centre (CDC) Occurrence of Species by Ecoregion (MSD, 2016a), the Bird Studies Canada (BSC) Manitoba Breeding Bird Atlas (BBA) and the Manitoba Herpetological Atlas (MHA). The species listed in these databases were cross-referenced with Schedule 1 of the Federal Species at Risk Act (SARA) SC 2002, C29 and The Endangered Species and Ecosystems Act (Manitoba), CCSM c E111 to determine the provincially listed rare or sensitive species with the ecoregion and Project Region. Furthermore, distribution maps and habitat requirements were examined to determine the likelihood of occurrence of federally and/or provincially listed species in the Project Region. Based on this search, there are 10 listed species that may occur in the Project Region (Table 4-3).

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Table 4-3: Federally and Provincially Listed Species that May Occur in the Project Region

Common Name

Scientific Name MBESEA1

Status SARA1 Status

Probability of Occurrence within 200 m of the Project Site

Flooded Jellyskin

Leptogium rivulare Not Listed Threatened

Unlikely - Very few occurrence records of this lichen in Manitoba (one cluster of occurrences near Flin Flon)

Boreal Woodland Caribou

Rangifer tarandus caribou

Threatened Threatened

Low to Moderate - A limited amount of caribou habitat is present at the site, but is not expected to be frequented by caribou due to the previously disturbed nature of the Project Site, immediate proximity to PR 392 (caribou have a tendency to avoid industrial and linear disturbances such as roadsa,b) and the community of Snow Lake

Little Brown Bat/Myotis and Northern Long-eared Bat/Myotis

Myotis lucifugus and Myotis

septentrionalis Endangered Endangered

Moderate to High - There is a marsh habitat within the Project Site (Figure 10) that would produce flying insects and attract foraging batsc - Terrestrial survey of the Project Site in June 2018 indicated that trees along Snow Creek (within the Project Site and Project Area) could provide suitable snags that could be used as bat maternity roostsc

Common Nighthawk

Chordeiles minor Threatened Threatened

Moderate to High - Suitable habitat occurs within the Project Site (Pipeline System) for this ground-nesting species, i.e. cleared areas, rocky outcrops and marshesd for foraging

Eastern Whip-poor-will

Caprimulgus vociferus

Threatened Threatened

Low to Moderate - Although potentially suitable habitat occurs at the Project Site for this ground-nesting species, i.e. semi-open forests or patchy forests with clearings such as forests that are regenerating following major disturbances e, the Project Site is near the northern limit of this species range according to the Manitoba Breeding Bird Atlas

Olive-sided Flycatcher

Contopus cooperi Threatened Threatened

Moderate - Potentially suitable habitat occurs at the Project Site for this tree-nesting species, i.e. forest openings/cleared areas, tall live or dead trees near wetland areas f

Barn Swallow Hirundo rustica Not Listed Threatened Low to Moderate - Man-made structures such as buildings at the existing New Britannia Mill and within the

https://www.birdatlas.mb.ca/accounts/speciesaccount.jsp?sp=WPWI&lang=en

https://www.birdatlas.mb.ca/accounts/speciesaccount.jsp?sp=WPWI&lang=en

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Common Name

Scientific Name MBESEA1

Status SARA1 Status

Probability of Occurrence within 200 m of the Project Site

community of Snow Lake occur within the Project Site and Project Area which provide nesting habitat for this species that builds a mud cup nest adhered to vertical surfaces under overhangs g

Bank Swallow Riparia riparia Not Listed Threatened

Low - No suitable steep riparian bank habitat occurs at the Project Site that would be suitable nesting habitat for this species which burrows into banks for nesting h

Rusty Blackbird

Euphagus carolinus Not Listed Special Concern

Low to Moderate - Potentially suitable habitat occurs at the Project Site for this tree-nesting species, i.e. near or over water in riparian vegetation (Snow Creek area). i

Shortjaw Cisco

Coregonus zenithicus

Not Listed Threatened

Unlikely -Shortjaw Cisco generally inhabit deep waters of large lakes, there is no habitat like this in the Project Area.

a Manitoba Boreal Woodland Caribou Management Committee 2015 b Schindler et al. 2007

c COSEWIC 2013a d COSEWIC 2007 e COSEWIC 2015 f Environment Canada 2016

g COSEWIC 2011 h COSEWIC 2013b i COSEWIC 2006

No specific Species at Risk critical wildlife habitat was observed on the Project Site or in the adjacent Project Area. Based on site conditions and field observations, it is expected that there is no critical wildlife value in the Project Area.

A breeding bird survey (BBS) was also conducted in June 2018 at five locations within representative habitats along the proposed Pipeline System route, 50 m north of the Manitoba Hydro transmission line ROW (Figure 15). The purpose of the BBS was to evaluate the potential presence of Species at Risk along the proposed Pipeline System route. The BBS was conducted as per the Handbook of Field Methods for Monitoring Landbirds, which states that surveying should be conducted at sunrise and concluding approximately four hours after sunrise (Ralph et al. 1993). No bird Species at Risk were encountered during the survey. Bird species observed during the BBS are listed in Table 4-4 and the location of the BBS stations are shown on Figure 15.

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Table 4-4: Results of Breeding Bird Survey

Station Number Location (UTM) Bird Species

NB_BBS_1 14U 435058 E 6082243 N • American Crow • Common Raven • Swainson's Thrush • Yellow-rumped Warbler • Tennessee Warbler • Chipping Sparrow

NB_BBS_2 14U 435708 E 6082005 N • Common Raven • Swainson's Thrush • Yellow-rumped Warbler • Tennessee Warbler • White-Throated Sparrow • Broad-Winged Hawk • Magnolia Warbler • Alder Flycatcher

NB_BBS_3 14U 436599 E 6081679 N • Common Raven • Swainson's Thrush • Yellow-rumped Warbler • Tennessee Warbler • Nashville Warbler • White-Throated Sparrow • Magnolia Warbler • Alder Flycatcher

NB_BBS_4 14U 437692 E 6081221 N • Wilson's Snipe • Common Raven • Ruby-crowned Kinglet • Swainson's Thrush • Tennessee Warbler • White-Throated Sparrow • Alder Flycatcher • Magnolia Warbler • Pileated Woodpecker

NB_BBS_5 14U 437712 E 6080944 N • Ruby-crowned Kinglet • Swainson's Thrush • Tennessee Warbler • Magnolia Warbler • White-Breasted Nuthatch • Bay-Breasted Warbler • Vesper Sparrow • Winter Wren

Nesting season in the Snow Lake region (zone C6) extends from the last week of April to the last week of August. While the peak migratory bird nesting season is estimated to last from May 12 to August 5, the

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shoulder migratory bird nesting season is estimated to last from April 28-May 11 and August 6- 20 (Government of Canada, 2018). No clearing may occur in the shoulder nesting season unless a nest search is conducted by a biologist no more than three days prior to clearing. If a nest is found, an appropriate ‘no activity’ buffer is established (e.g. 60 m) until the nest is no longer active and the young have left the nesting area.

4.8 Aquatic Environment

The baseline assessment was carried out in order to document the conditions of the aquatic environment which could potentially be affected by construction or operation of the proposed Project. The detailed methodology and results of the assessment are described in the Aquatic Environment Technical Data Report attached as Appendix F. A summary of the methodology and results is presented in the following section.

4.8.1 Methods

4.8.1.1 Sampling Sites and Parameters

Water chemistry, sediment chemistry, phytoplankton, zooplankton, benthic invertebrates, and fish and fish habitat were assessed for the aquatic environment baseline. A total of six waterbodies and ten sites were included in the 2018 field studies. Fieldwork occurred from June 25 to 29, 2018, and from September 16 to 24, 2018. Data was collected in a six waterbodies, selected based on their proximity to the Project components, including the New Britannia Mill, the Pipeline System, and the Stall Concentrator/Anderson TIA. In those six waterbodies, a total of ten sites were selected for study, as follows:

• Anderson Creek – One Site. • Anderson Bay of Wekusko Lake – One Site. • Snow Bay of Wekusko Lake – Two Sites. • Stall Creek – One Site. • Snow Creek – Three Sites. • Snow Lake – Two Sites.

Previous studies have been conducted in Anderson Creek, Anderson Bay, Stall Creek, and Snow Lake by AECOM and others on behalf of Hudbay in support of previous mining projects and in fulfillment of regulatory obligations. Existing information for these four waterbodies was reviewed and considered in this assessment. Snow Creek and Snow Bay had not been subject to previous study by AECOM or Hudbay. The field sites and environmental components sampled in 2018 are summarized in Table 4-5.

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Table 4-5: New Britannia 2018 Field Programs

Waterbody Site ID UTM (NAD83, 14U) Environmental Component 2018 Field Programs

Easting Northing JUN SEP

Wekusko Lake: Anderson Bay ANB_01A 439466 6076571

Water Chemistry X X

Sediment Chemistry X X

Phytoplankton X X

Zooplankton X X

Benthic Invertebrates ---- X

Wekusko Lake: Snow Bay

SBY_1 443583 6080148

Water Chemistry X X Sediment Chemistry X X Phytoplankton X X Zooplankton X X Benthic Invertebrates ---- X

SBY_2 443167 6079025

Water Chemistry X X Sediment Chemistry X X Phytoplankton ---- ---- Zooplankton ---- ---- Benthic Invertebrates ---- X

Anderson Creek ANC_06 439131 6077625

Water Chemistry X X

Sediment Chemistry X X Phytoplankton X X Zooplankton X X Benthic Invertebrates ---- X

Snow Creek

SNCK_1 437297 6080993

Water Chemistry X X Sediment Chemistry X X

Minnow Traps ---- X Electrofishing X X Habitat Assessment X ---- Phytoplankton X X Zooplankton X X Benthic Invertebrates ---- X

SNCK_2 437860 6080981

Water Quality X X Sediment Quality X X Minnow Traps ---- X Electrofishing ---- X Habitat Assessment X ---- Phytoplankton ---- ----

Zooplankton ---- ---- Benthic Invertebrates ---- X

SNCK_3* 443716 6081902 Water Quality X X Sediment Quality X X Minnow Traps X X

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Waterbody Site ID UTM (NAD83, 14U) Environmental Component 2018 Field Programs

Easting Northing JUN SEP Electrofishing X X Habitat Assessment X ---- Phytoplankton ---- ---- Zooplankton ---- ----


Snow Lake

SLK_1 433884 6079964

Water Quality X X Sediment Quality X X Phytoplankton X X Zooplankton X X Benthic Invertebrates ---- X

SLK_2 435907 6081023

Water Quality X X Sediment Quality X X Phytoplankton ---- ---- Zooplankton ---- ---- Benthic Invertebrates ---- X

Stall Creek STCK_1 439873 6077017

Water Quality X X

Sediment Quality X X

Minnow Traps ---- X

Phytoplankton X X

Zooplankton X X


4.8.1.2 Surface Water Chemistry

The objectives of the surface water sampling program were to collect in situ data and water samples for analysis from the ten sample sites located in the six identified waterbodies. Including duplicates and bottom samples, a total of 22 water samples were collected. Samples were analyzed for the following parameters:

• Major anions (alkalinity, chloride, sulfate). • Nutrients (nitrogen, phosphorus, reactive silica). • Total organic carbon, total inorganic carbon. • Total and dissolved metals, including mercury. • Aggregate organics (CBOD). • Plant pigments.

Water chemistry data were compared with the Canadian Council of Ministers of the Environment (CCME) Water Quality Guidelines (WQG) and the Manitoba Water Quality Standards, Objectives and Guidelines (MBWS 2011). For parameters that had both federal and provincial guidelines, the most conservative guideline was used.

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The trophic status of the sampled waterbodies was determined using categories based primarily on total phosphorus threshold concentrations (CCME 2004; Dodds et al 1998), but with comparison to total nitrogen thresholds.

4.8.1.3 Sediment

The objective of the sediment sampling program was to collect sediment samples for physical and chemical analysis from ten sample sites located in the six identified waterbodies. Samples of surficial sediment were collected at each of the ten sites using multiple petite Ponar dredges. Approximately 1,000 mL of sediment was collected at each site and shipped to ALS in Winnipeg for processing and analysis. Sediment chemistry data were compared with the Canadian Council of Ministers of the Environment (CCME) Interim Sediment Quality Guidelines (ISQG), and Probable Effects Level (PEL) for the Protection of Aquatic Life (PAL) (CCME 2018).

4.8.1.4 Phytoplankton

The objective of the phytoplankton sampling program was to collect surface samples for enumeration from the six identified waterbodies. Phytoplankton samples were collected at one site in each waterbody for a total of six samples. The samples were preserved and submitted to AAE Tech Laboratories in St. Anne, MB, for processing, analysis of algal biomass, and taxonomic identification to the lowest practical level.

4.8.1.5 Zooplankton

The objective of the zooplankton sampling program was to collect samples for enumeration from the six identified waterbodies. Zooplankton samples were collected at one site in each waterbody for a total of six samples using a 1.0 m long, 63 µm mesh size conical net, with a weighted cod-end attached to a single 0.12 m or 0.25 m diameter steel hoop frame. Upon retrieval, zooplankton were collected and preserved, then submitted to AAE Tech Laboratories in St. Anne, MB, for processing and taxonomic identification to the lowest practical level.

4.8.1.6 Benthic Invertebrates

The objective of the benthic invertebrate sampling program was to collect samples for enumeration from ten sample sites located in the six identified waterbodies. Sediment samples for description of the benthic invertebrate community were collected at all ten sites. One sample was collected from each location, consisting of a single petite Ponar dredge. Each sample was sieved in the boat through a 500 µm mesh, preserved with 70% ethanol, and submitted to AAE Tech Laboratories in St. Anne, MB, for processing and taxonomic identification to the lowest practical level.

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4.8.1.7 Fish Community

Fish sampling was conducted in June 2018 and September 2018 to characterize the existing fish and fish community of Snow Creek. The objective of the fish community sampling program was to capture, identify, and measure fish from Snow Creek using backpack electrofishing and minnow trapping. All captured fish were identified to species, enumerated, and measured for total length (cm) and weight (g). Sampling effort and location is detailed in the Aquatic Environment Technical Data Report (attached as Appendix F).

4.8.1.8 Fish Habitat

The objective of the baseline fish habitat assessment of Snow Creek was to characterize the fish habitat in Snow Creek using sites SNCK_1, SNCK_2, and SNCK_3. At each site, fish habitat was assessed at six transects, spaced over approximately 400 m of channel length. The following habitat characteristics were assessed at each transect:

• Channel characteristics, including depths, bankfull and wetted widths, gradient, morphology, and substrate compaction and embeddedness.

• Substrate particle size distribution, including percent organic matter, fines, sand, gravel, cobble, boulder, and bedrock.

• Characteristics of the riparian areas, including vegetation type, bank stability, material, and slope. • Overall percent instream cover for fish and contributions from overhanging vegetation, instream

vegetation, undercut banks, boulders, deep pools, and woody debris. • Mesohabitat type, including backwater, pool, riffle, run and rapid.

4.8.2 Results

4.8.2.1 Water Quality

Surface Water Characterization

Surface water temperatures were seasonal, and ranged from 18°C to 22°C in June, and from 7°C to 12°C in September. Regardless of the season, the surface waters in the study area were well oxygenated at all sites. Five of the six sampled water bodies were alkaline, with pH values consistently above 7.5. The exception was Anderson Creek, where the water was circumneutral, with a pH of just over 7.0. This indicates that pH in Anderson Creek is slightly less than that observed in the other five waterbodies, which is consistent with the use of Anderson Creek as the discharge location for the Anderson TIA. Not surprisingly, alkalinity was also reduced in Anderson Creek in comparison with the other five waterbodies; approximately 20 mg CaCO3 at Anderson Creek, versus 50 mg CaCO3 to 100 mg CaC03 at the other five waterbodies. The dominant anion was bicarbonate at Snow Bay, Snow Lake, Snow Creek and Stall Creek, while at Anderson Bay and Anderson Creek the dominant anion was sulfate. At Anderson Creek, the sulfate concentration was over 600 mg/L, while for the other waterbodies the sulfate concentration was less than 25 mg/L. Sulfate in Anderson Bay was also elevated, with the average concentration at approximately 200 mg/L. This data indicates that Anderson Creek is influenced by discharge from Anderson TIA.

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The dominant cation was calcium at all sites, with low concentrations of the other major cations sodium, potassium, and magnesium. However, at Anderson Creek and Anderson Bay, calcium concentrations were elevated in comparison with the other four waterbodies: the calcium concentration was over 250 mg/L Ca at Anderson Creek, almost 100 mg/L Ca at Anderson Bay, but less than 30 mg/L Ca at Snow Bay, Snow Lake, Snow Creek, and Stall Creek. These results again highlight that water chemistry in Anderson Creek is being influenced by discharge from Anderson TIA. Based largely on the calcium concentration, Anderson Creek and Anderson Bay were classified as very hard water (> 180 mg CaCO3/L), and the other four waterbodies as soft (30 mg/L to 60 mg/L), to medium hard (60 mg/L to 120 mg/L) water. The total phosphorus (TP) concentration amongst the six waterbodies was variable. The highest concentrations were recorded in Anderson Creek, where the mean TP was estimated at just below 0.080 mg/L. The concentration in Anderson Bay was only slightly lower, where the mean TP was estimated at just below 0.060 mg/L. These TP concentrations classify both Anderson Creek and Anderson Bay as eutrophic, or highly productive. In contrast, Snow Bay, Snow Lake and Stall Creek had lower TP concentrations and were classified as mesotrophic. Snow Creek was the least productive waterbody amongst the study sites, and was classified as oligotrophic. Comparison of the total nitrogen data with trophic classification values indicate broad agreement with the classification of trophic status based on TP concentration.

Water Quality

During the spring 2018 survey, the total suspended solids or turbidity guideline was exceeded in Anderson Bay, Snow Bay, Snow Creek and Stall Creek for at least one site in each waterbody. During the fall 2018 survey, water was clearer and the total suspended solid guideline was only exceeded at one site in Snow Lake and in Stall Creek. Similarly, the CCME guideline for total aluminum was exceeded during the spring 2018 survey in Anderson Bay, Snow Bay, Snow Lake, Snow Creek and Stall Creek for at least one site in each waterbody. During the fall 2018 survey, total aluminum was only exceeded at one site in Stall Creek and one site in Snow Bay. The disparity in turbidity and aluminum levels between spring and fall surveys highlight the effect of water level and flow on water quality. In spring, when levels are generally high and flows are relatively rapid, particulate materials are mobilized into the water column and water is turbid. Associated with these particles are aluminum ions associated with the entrained clay. Apart from turbidity and aluminum, exceedance of guideline values in surface waters (for at least one sample in each waterbody) for specific analytes included the following:

• Anderson Bay: chromium, copper, iron, selenium, and zinc. • Anderson Creek: copper, selenium, and zinc. • Snow Bay: chromium, and iron. • Snow Creek: chromium, and iron. • Stall Creek: iron. • Snow Lake: no water quality guidelines were exceeded.

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4.8.2.2 Sediment

Sediment Characterization

Sediment particle size was variable amongst the six waterbodies. Anderson Creek and Snow Creek sediments contained the most sand, while the other four waterbodies were composed primarily of finer material. Sediments collected from Anderson Bay were dominated by silt particles, while sediment from Snow Bay, Snow Lake, and Stall Creek contained a relatively even mixture of silt and clay particles. Total organic carbon was also variable among waterbodies, although related to particle size. Anderson Creek and Snow Creek sediments contained the least amount of total organic carbon (<5%), but the highest amount of sand (>50%). The other four waterbodies contained varying amounts of total organic carbon, ranging from approximately 6% to 21%. Major cations in the sediment (excluding aluminum) included iron, manganese, calcium, and potassium. The dominant cations were iron, which ranged from 35% to 45% of the total cationic charge, and magnesium, which ranged from approximately 30% to 35% of the total charge. Calcium and potassium were at lower concentrations, with other cations being minor constituents in comparison. The relative content of the major cations was consistent among the six waterbodies, with no large differences apparent.

Sediment Quality

All parameters that exceeded guidelines are listed below. Exceedance of ISQG in sediment (for at least one sample in each waterbody) included the following:

• Anderson Bay: arsenic, cadmium, and copper. • Anderson Creek: no ISQG sediment guidelines were exceeded. • Snow Bay: copper. • Snow Lake: cadmium, chromium, copper, lead, and zinc. • Snow Creek: arsenic, and chromium. • Stall Creek: no ISQG sediment guidelines were exceeded.

Exceedance of PEL (for at least one sample in each waterbody) for specific analytes included the following:

• Anderson Bay: zinc. • Anderson Creek: arsenic, cadmium, copper, lead, mercury, and zinc. • Snow Bay: arsenic. • Snow Lake: arsenic. • Snow Creek: no PEL sediment guidelines were exceeded. • Stall Creek: no PEL sediment guidelines were exceeded.

Evaluation of the sediment chemistry data against the ISQG indicated that multiple metals exceeded guidelines at all sites except Stall Creek. However, evaluation against the PEL indicated that Anderson Creek was the only site with multiple metals exceeding the relevant guideline. These data indicate that Anderson Creek has a metal load in the sediment considerably greater than at the other five waterbodies.

Arsenic exceeded the CCME ISQG of 5.9 mg/kg dry wt. at five of the six waterbodies. However, only three waterbodies exceeded the CCME PEL (CCME 2018) arsenic content of 17 mg/kg dry wt. This

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indicates that although arsenic content was elevated within these five waterbodies, the arsenic content at most sites was at a level less likely to result in effects to biota.

4.8.2.3 Phytoplankton

The phytoplankton community among the six waterbodies contained 174 distinct taxonomic groups identified to the lowest practical level, and contained within nine separate phyla. For individual sites, taxon richness ranged from five taxa in Stall Creek in the spring 2018 survey, to 57 taxa at Snow Bay in the spring 2018 survey. Richness was therefore spatially variable. There was also variability in taxon richness between samples collected in spring 2018 and those collected in fall 2018. At Anderson Bay, Anderson Creek and Stall Creek, taxon richness was two to three times higher in fall 2018, while for sites in Snow Bay, Snow Creek and Snow Lake taxon richness was higher in spring 2018. Phytoplankton density was also spatially variable. In spring 2018, density among the six waterbodies ranged from approximately 0.0019 x 108 units or cells/L to 2.71 x 108 cells or units/L, which is a difference of greater than 1,000 times. Similarly, in fall 2018 density among the six waterbodies ranged from approximately 0.012 x 108 units or cells/L, to 1.55 x 108 organisms/L. Estimated phytoplankton biomass (calculated from the density data) was also spatially and temporally variable, although not entirely consistent with the variability in density. That is, the waterbodies with the highest phytoplankton density did not necessarily have the highest biomass. This is because biomass depends not only on phytoplankton density, but also on the size of the phytoplankton. As the phytoplankton community evolves through the seasons, the average size will also vary. For instance, in Anderson Bay the density was higher in the fall 2018 survey, but the biomass was considerably greater in the spring 2018 survey, and in Snow Bay the opposite was true. Cyanophytes, or blue-green algae, were the most abundant phytoplankton at all locations, with the exception of Snow Bay and Stall Creek in fall 2018, where the Chrysophytes, or golden algae, were dominant. Other abundant taxonomic groups included the Diatomeae, or diatoms, and the Chlorophytes, or green algae. Despite the temporal variability in phytoplankton density (as discussed above), for four of the waterbodies the relative phytoplankton density, which is a measure of community structure, was comparable over time. At Anderson Bay, Anderson Creek, Snow Creek and Snow Lake, the blue-green algae were most abundant in both the spring and fall 2018. In contrast, in Snow Bay and Stall Creek the blue-green algae were most abundant in spring 2018, while the golden algae were dominant in fall 2018. Blue-green algae, which dominated the phytoplankton community based on density, were only a minor component of the biomass of the phyotoplankton community. Instead, the phytoplankton biomass was largely composed of diatoms and golden algae, with the Cryptophyceae, or cryptomonads, also of importance at a few waterbodies. The consistency in relative density was also not observed for relative biomass. The composition of the phytoplankton community based on biomass was variable amongst the six waterbodies, and at most waterbodies there was also considerable temporal variability as the phytoplankton community evolved through the open-water season.

4.8.2.4 Zooplankton

A total of 13 distinct taxonomic groups at the lowest practical level were enumerated, including six families in the Order Cladocera, five families in the Subclass Copepoda, and two families in the Phylum

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Rotifera. For individual sites, taxon richness ranged from five taxa at Anderson Bay in spring and fall 2018, to ten taxa at Anderson Creek in spring 2018. Zooplankton density was spatially variable. In spring 2018, density among the six waterbodies ranged from approximately 700 organisms/m3 to over 37,000 organisms/m3, which is a difference of greater than 50 times. Similarly, in fall 2018, the density among the six waterbodies ranged from approximately 800 organisms/m3 to almost 30,000 organisms/m3. The variability in density was possibly related to the wide variety in aquatic habitat among the sites, which ranged from lakes to creeks, from relatively fast-flowing water to calm waters, and from sand to clay sediment. Zooplankton density was also temporally variable. The RPD calculated for the spring and fall 2018 data ranged from 25% to almost 180% among the six waterbodies. These are high numbers, considering that RPD calculated on the data average has a maximum value of 200%.

There were four prevalent zooplankton groups among the six waterbodies, which in order of total abundance included cladocerans, copepods, rotifers, and ostracods. The cladocerans and copepods were found at all sites and were therefore relatively prevalent in comparison with the rotifers and ostracods that were absent from several sample sites. Despite the temporal variability in zooplankton density, at four of the sites the relative zooplankton density, which is a measure of community structure, was comparable over time. In Anderson Bay and Snow Bay the copepods were dominant for both the spring and fall 2018 samples, while in Snow Creek and Snow Lake the cladocerans were dominant. In contrast, in Anderson Creek the spring 2018 sample contained a large number of rotifers which were absent from the sample collected in fall 2018. Similarly, at Stall Creek, ostracods were enumerated in large number in spring 2018, but not in fall 2018.

4.8.2.5 Benthic Invertebrates

A total of 30 taxonomic groups at the lowest practical level were enumerated. For individual sites, taxon richness ranged from four taxa in Snow Lake, to 12 taxa in Anderson Creek. The richness data were based on LPL identification, so it is likely that the actual species richness was some amount greater than the recorded taxon richness. Benthic invertebrate density ranged from fewer than 1,000 individuals/m2 at both Snow Lake sites, to almost 10,000 individuals/m2 in Snow Creek. In Snow Creek, density ranged from approximately 1,800 individuals/m2 at one sampling location, to approximately 9,200 individuals/m2 at another location. The distribution of benthic invertebrates in Snow Creek was therefore patchy and not uniform. Among the ten sites, the benthic invertebrate community was dominated by six taxa overall that comprised approximately 78% of the community. These six taxa were collected in more than half the sites, or were found at a relative density of 5% or greater. The six taxa included midges, two general of mayflies, two families of snails, and a bivalve. All these taxa are prevalent in depositional environments with fine-grained sediment, such as lakes and slow-moving rivers. Of the six taxa, the midges, which are classified as true flies, were found at all ten sites with an average relative density of almost 35%. The midges were therefore the dominant species overall among the ten sites.

At individual sites, the dominant taxa were variable. While midges were present at all sites, they were the most common species at Anderson Creek and Stall Creek. At Anderson Bay, the most common species were the snails, while at Snow Creek the most common species were the mayflies. At sites in Snow Bay and Snow Lake, taxa other than the dominant species were the most abundant. The between-site

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variability highlights the uneven distribution of benthic invertebrate taxa and the complexity of benthic invertebrate communities.

4.8.2.6 Fish Community

The fish-bearing water body that may be directly affected by the Project is Snow Creek. Snow Creek is located in the Nelson River watershed, which contains at least 34 species of freshwater fish, of which 31 are native and three are introduced species (Stewart and Watkinson 2007). Ten species of fish were caught during the 2018 field work (see Table 3.5 in the Aquatic Environment Technical Data Report, attached as Appendix F), listed below:

• Longnose dace (Rhinichthys cataractae). • White sucker (Catostomus commersonii). • Lake chub (Couesius plumbeus). • Slimy sculpin (Cottus cognatus). • Yellow perch (Perca flavescens). • Pearl dace (Margariscus margarita). • Brook stickleback (Culaea inconstans). • Fathead minnow (Pimephales promelas). • Johnny darter (Etheostoma nigrum). • Common shiner (Luxilus cornutus).

Of these ten species, nine are commonly found in the Nelson River watershed. The common shiner, however, is not considered to occur in the Nelson River watershed, but is restricted to south and eastern Manitoba (Stewart and Watkinson 2007). Considering the species native range, it was likely a misidentification of a similar shiner species. A total of 61 fish were caught. Of the ten species that were captured, the most commonly caught were white sucker (n=14), followed by longnose dace (n=10) and brook stickleback (n=8); the other seven species were caught less frequently. The white sucker were all juvenile fish, ranging in length from 2 cm to almost 10 cm, with a mean total length of 4.5 cm. The other species were small-bodied fish, ranging in average size from 4.7 cm to 10.6 cm.

4.8.2.7 Fish Habitat

A detailed description of the aquatic habitat at each of the assessed creek segments is available in Appendix F. In general, Snow Creek supports a wide variety of fish habitat conditions. Overall, Snow Creek was characterized as a broad, slow-moving stream, dominated by flat habitat. The most commonly-encountered channel substrates were fines and sand, with occasional patches of cobble and boulder. Channel widths varied within each site and at the three different sites, ranging from 15 m to 100 m. Riparian vegetation was dominated by mature coniferous forest and fallen trees were abundant throughout the study sites. Notably, one short reach downstream of the Snow Lake outlet, approximately 180 m long, had relatively narrow channel, faster flows, a higher gradient, and larger substrates than the downstream reaches.

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4.9 Socio-Economic Environment

The Project Site is located within the municipal boundaries of the Town of Snow Lake (Figure 16). The portion of the Project that contains the proposed route of the Pipeline System lies within an area that is zoned as Limited Development, Unsurveyed Lands. The Snow Lake Mining District has been developed for mining purposes for over 50 years. Hudbay has played an integral part in this history since the late 1950s, by operating many mines in the area including: Photo Lake, Chisel Lake, Stall Lake, Osborne Lake, Rod Mine, Spruce Point, Ghost Lake, Anderson Lake, Chisel North, Reed and Lalor. Hudbay’s 777 mine will come to the end of operations in 2021. At that time, Hudbay anticipates that the Flin Flon Mill and Zinc plant will be placed in care and maintenance. This will result in a good deal of change in economic conditions in Flin Flon and surrounding area. In terms of planning for employment needs in the future, Hudbay’s first priority is to define future workforce requirements in Snow Lake, where opportunities are expected to lie. It is believed that the best scenario for Hudbay’s business and for Hudbay employees is to refurbish the New Britannia gold mill, which will create jobs and provide opportunity for gold exploration in the Snow Lake area. Resumption of operation of the New Britannia Mill will make it more economic to develop any viable gold opportunities that may be identified over the next several years. Thus the proposed Project is important to the economic future of communities in the Snow Lake area and also, more broadly, in the region. Hudbay also has resumed active exploration in Manitoba, spending approximately $19 million in 2018 in Manitoba alone. For example, in the Goose Lake area, near Cranberry Portage, an airborne survey has identified favourable targets that are expected be part of a drill program over the winter of 2019. As well, work is advancing on the Pen Zone, near Snow Lake, which appears to be a small, near surface zinc deposit. These projects are indicative of Hudbay’s continuing efforts to identify viable opportunities in Northern Manitoba. According to the 2016 census conducted by Statistics Canada, the population of Snow Lake was 899 residents (Statistics Canada, 2017). Hudbay’s Snow Lake Camp provides accommodation for an additional approximately 300 people. Many Snow Lake residents are employed in the mining industry and related services. Based on Government of Manitoba and Federal sources, there is no Indian Reserve within the Project Region. Indigenous communities in closest proximity to the Project Region are Mathias Colomb Cree Nation (approximately 125 km northwest), Nisichawayasihk Cree Nation (approximately 123 km northeast), Mosakahiken Cree Nation (approximately 133 km south), Opaskwayak Cree Nation (approximately 142 km southwest), Pimicikamak Cree Nation (approximately 147 km east) and Norway House Cree Nation (approximately 177 km southeast) as shown on Figure 17.

4.9.1 Parks and Natural Areas

There are no national parks, or designated protected areas in the Project Region. There is one provincial park located within the Project Region; Wekusko Falls Provincial Park (0.88 km2) located approximately 8 km south of the end of the Pipeline System at the Stall Concentrator as shown in Figure 16.

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4.9.2 Heritage Resources

Information from the Historic Resources Branch of Manitoba Culture, Heritage and Tourism does not indicate any historic or heritage resources in the Project Region. The closest heritage resource of significance is located approximately 20 km south/southwest of the Project Site at Tramping Lake, the site of one of Manitoba’s largest known concentrations of pictographs. A Heritage Screening Request was sent to Manitoba Heritage Resources Branch (HRB) on October 23, 2018. The HRB reply, which is attached in Appendix G, indicates that, based on the geography of the route and existing contiguous infrastructure and uses, “the potential to impact significant heritage resources is considered low and, therefore, the HRB has no immediate concerns with the proposed development.” As the alignment of the tailings pipeline changed after our initial Heritage Screening Request, an update to the alignment was sent to HRB on January 8, 2019. The HRB response, which is also attached in Appendix G, indicates that, based on the geography of the route and existing contiguous infrastructure and uses, “the potential to impact significant heritage resources is considered low and, therefore, the HRB has no immediate concerns with the proposed development.” In addition, during the field surveys, the traditional knowledge holders were asked to point out any feature of heritage interest that they might identify. None were identified.

4.9.3 Regional Resource Use

In addition to mining activities, extensive forestry operations have occurred within the region and surrounding area, with wood sent to the pulp and paper mill operation in The Pas, Manitoba. Canadian Kraft Papers Industries Ltd., located in The Pas has three Forest Sections (Highrock, Nelson River and Saskatchewan River) where wood may be harvested. Trapping, fishing, and hunting are also popular activities in the region. The Lalor Mine Environment Act Proposal Report (AECOM, 2012b), available on the Manitoba Department of Sustainable Development public registry, set out a description of land uses in the vicinity of the Project Region which continues to reflect current activities. Restrictions on potential uses by others of the areas lying within or near the proposed route of the Pipeline System are imposed by the Town of Snow Lake Municipal By-law Number 733/94, Being a By-Law to Prevent the Use of Firearms and Bows and Arrows in Certain Areas, as amended by By-law Number 780/96. The entire route of the Pipeline System lies within an area in which the use of weapons is prohibited for the purpose of protecting human safety. The only persons exempt from this restriction would be Registered Trapline Holders, who are permitted to hunt.

4.9.3.1 Registered Trapline Owners

Figure 16 shows traplines in the Snow Lake Region. The route of the Pipeline System transects three Registered Traplines (RTLs):

• RTL #16 (within the Townsite of Snow Lake; youth trapline); • RTL #13: Russel Bartlett; and • RTL #22: Wayne Galiz.

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Hudbay has commissioned local trappers, including the owner of RTL13, to provide assistance with beavers located on or impacting Hudbay facilities in Snow Lake. Hudbay will continue this arrangement with local trappers, as needed, in an expanded role once the New Britannia Mill is commissioned and in operation. Hudbay has been in contact with these trappers regarding the Project. The results of these discussions are below in Section 6.10.1.

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5. Public and Stakeholder Engagement

In advance of conducting the public and stakeholder engagement for this Project, Hudbay identified regional stakeholders, regulatory bodies and special interested group that may have an interest in the Project or that may be potentially impacted by the Project. Engagement with these identified entities is outlined in this section. Section 5.3 below outlines Hudbay’s engagement with Indigenous communities and included in its efforts any communities located within closest proximity. Hudbay maintains regular communication with the Town of Snow Lake Mayor and Council, the Town of Snow Lake Chamber of Commerce, and Indigenous communities. The following subsections outline the public and stakeholder engagement activities that were conducted by Hudbay and AECOM for the Project. There were two phases of engagement for the project:

• May 2018: Prior to field season to gain input on the field studies that were planned for the Project and provide feedback on Project options.

• December 2018: To share the results from the field studies and the environmental assessment and gain local input and address questions pertaining to the Project.

The following entities were contacted regarding the Project:

Regional stakeholders:

• Town of Snow Lake. • SnoMan (Snowmobile Association). • Registered Trapline Owners. • Opaskwayak Cree Nation. • Mathias Colomb Cree Nation. • Mosakahiken (Moose Lake) First Nation. • Town of Snow Lake Rangers. • RCMP – Snow Lake Detachment. • Joseph H. Kerr School. • Town of Snow Lake Chamber of Commerce.

Regulatory bodies:

• Manitoba Department of Sustainable Development. • Manitoba Mines Branch. • Manitoba Heritage Resources Branch.

Educational organizations:

• Northern Manitoba Mining Academy. • Northern Manitoba Sector Council. • University College of the North.

The New Britannia Mill site is a wholly developed operational site, which has been a mine site since 1948. Similarly, the end of the Pipeline System is within an active area that is occupied by Hudbay’s Stall Concentrator. The area in between the New Britannia Mill site and the Stall Concentrator, to be occupied

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by the Pipeline System, lies within the area subject to Town of Snow Lake By-law which, for reasons of human safety, prohibits hunting to all except registered trapline owners.

Engagement activities included:

• Stakeholder meetings with key project stakeholders to facilitate a better understanding of their environmental concerns as part of the permitting process. Meetings occurred in the Town of Snow Lake in May 2018 and December 2018, prior to each of the two public information sessions.

• Public information sessions in the Town of Snow Lake in May 2018 and December 2018. The purpose of the sessions was to provide the public with an opportunity to learn about the Project and provide their feedback on Project options. Both information sessions included a presentation of the Project with a question and answer period, followed by an informal period after where participants could view storyboards and ask questions to Project team members.

5.1 Public and Stakeholder Engagement Activities in May 2018

5.1.1 Stakeholder Meetings

5.1.1.1 Town of Snow Lake Mayor and Council – May 29, 2018

The meeting began with a description of the Project and outlined the different pipeline routing options (Option 1: tracking PR 392; Option 2: tracking existing Manitoba Hydro corridor). The Snow Lake Mayor and Council (Council) identified the following issues:

• Water supply for the mill and the integrity of the freshwater pipe from Snow Lake (indicating their belief that the freshwater pipe is in need of repair).

• Safety on the Snow Creek Bridge: the bridge is narrow and there are concerns about ore trucks sharing the bridge with standard vehicles.

• Traffic volume (number of trucks per hour) and trucking hours. • Curves and approaches near the bridge and along PR 392 (specifically near landfill).

Hudbay advised during the meeting that they were planning for three trucks per hour and that they would operate during “daylight hours”, in the safest manner possible. Hudbay indicated that traffic and bridge studies were in progress. The Council provided the following information about resource users in the Project Area:

• Snowmobile club uses the Hydro ROW as a route. • Junior trappers trap in the area. • One trapline is located in the area. • There is a warming station at Herblet Lake.

AECOM described the environmental studies that were planned for spring 2018 and the air quality and noise modelling that would be completed. The Council indicated that residents on Cedar Avenue had previously received a tax break due to the vibration cause by blasting in the former New Britannia Mine. Hudbay explained that the mine would not be operating, only the mill, and that vibration would not be an issue as it had been under the previous operator.

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5.1.1.2 Town of Snow Lake Chamber of Commerce – May 29, 2018

Hudbay and AECOM met with the Snow Lake Chamber of Commerce in May 2018 (and again in December 2018), prior to both Public Information Session events. At both meetings, the Chamber of Commerce vocalized their support for the Project as it will provide more jobs in the Town of Snow Lake. The Chamber of Commerce is trying to grow the population of the Town of Snow Lake. The Chamber of Commerce expressed appreciation for a Project providing approximately 50 full-time positions. The Chamber of Commerce hopes that full-time employees will move to the Town, potentially stimulating other business and services in the Town to grow. The Chamber of Commerce discussed some incentive ideas for encouraging people to buy homes in the Town versus staying at the Snow Lake Camp.

5.1.2 Public Information Session – May 29, 2018

Representatives from Hudbay and AECOM delivered a PowerPoint presentation and then were available to guide participants through the storyboards and answer questions asked by participants. The public information session was well-attended, with 77 participants that signed in, and additional participants that preferred to not sign in. The information session gave the public the opportunity to:

• Review Project information and provide feedback on Project options (tailings pipeline routes). • Comment on planned environmental studies. • Express concerns and request information. • Discuss the Project with Project representatives from Hudbay and AECOM.

Materials developed for the event included:

• PowerPoint presentation delivered by Hudbay and AECOM describing the proposed Project, Project options, and planned environmental studies.

• Display Storyboards (13) describing the Project. • A feedback form for attendees.

Copies of these materials are attached in Appendix H.

5.1.2.1 Notification Methods

Newspaper Advertisement

An advertisement was run in Flin Flon’s The Reminder on May 23, 2018. The advertisement contained the purpose of the event and event details. The Town of Snow Lake no longer has a local newspaper but The Reminder is available in the Town. Copies of the advertisements are attached in Appendix H.

Poster Advertisement

Posters containing the purpose of the event and event details were posted around the Town of Snow Lake at local establishments (e.g. grocery store, pharmacy, bank, etc.). A copy of the poster is attached in Appendix H.

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Letter Invitation

A letter invitation was sent via email to significant stakeholders/special interest groups. Copies of these letters are attached in Appendix H.

Town of Snow Lake Community Events Website

An event description was posted on the Town of Snow Lake website’s community calendar.

5.1.2.2 Summary of Feedback Received

Twenty-six (26) feedback forms were received from the attendees at the public information session. To protect the privacy of the attendees, copies of the comment sheets will be provided to Manitoba Sustainable Development pursuant to Section 47 of the Environment Act which provides for regulators to receive confidential information. A sample comment sheet can be found in Appendix H. The following subsections summarize the comments received.

5.1.2.3 Feedback on How People Heard About the Event

Attendees were asked how they heard about the public information session, through the newspaper, word of mouth, poster, letter invitation, or Facebook. The most common way people heard about the event was word of mouth, followed by poster and then Facebook.

Chart 5-1: How People Heard About the Event

Note: Respondents had the option of selecting more than one answer.

5.1.2.4 Feedback on the Public Information Session

Respondents were asked if they found the public information session useful. Twenty-two (22) of 26 respondents found the session useful, with four respondents leaving the question blank.

0

2

4

6

8

10

12

Word ofMouth

Poster Facebook Newspaper Town of SnowLake Website

LetterInvitation

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5.1.2.5 Feedback on Project Interest

Respondents were asked to comment on any specific interests concerning the Project moving forward. Eighteen people responded to this question. Nine respondents indicated they were interested in the potential economic benefits and opportunities the Project could provide for the Town of Snow Lake, including hiring local employees. One respondent indicated concern about accommodations for new employees. Five respondents indicated they were concerned about traffic, including the Snow Creek Bridge and road conditions, and safety. Other interests included water quality downstream of Anderson TIA (specifically Wekusko Lake), wildlife, cyanide leaching, and tailings. These concerns are addressed in the discussion below (Section 5.1.2.8).

5.1.2.6 Feedback on the Proposed Pipeline Route Alternatives

Respondents were asked if they had any information on the proposed pipeline route alternatives (one tracking the Manitoba Hydro Transmission Line corridor and the other tracking PR 392). Five people answered this question. Four of the five people indicated they prefer the Manitoba Hydro Transmission Line option because it would minimize impact to the community and the environment. One respondent indicated that both options will affect ski and snowshoe trails.

5.1.2.7 Other Comments

Eighteen people left other comments regarding the Project. These comments have been organized into themes, and responses to them are as follows:

Table 5-1: Other Comments

Theme Specific Concern/Inquiry Response

Traffic Road conditions. Maintenance of PR 392 is ultimately Manitoba Infrastructure’s responsibility. Hudbay will continue to work with MI to ensure the road is safe for public use.

Traffic volume and safety. Safety is Hudbay’s top priority. Mitigation measures discussed below in Sections 6.10.5 and 6.11.4 will be implemented to ensure public and employee safety.

Haulage road should be considered.

At the time of this Information Session, Hudbay was considering all options for ore haulage as studies were still in progress. Based on the results of the traffic impact study (Appendix C) it was determined that the existing route could be used with no upgrades.

Noise/Dust What mitigation measures are being considered for noise/dust?

Mitigation measures for noise and dust can be found in the Appendix E (noise impact assessment), Appendix D (air quality assessment), and Section 6.6.

Support General supportive comments. N/A. Resource Use Snowmobile trails will be affected. Hudbay will provide access across the pipeline for the

resource users in Snow Lake.

5.1.2.8 Other Discussion

Following the PowerPoint presentation, the floor was opened up to questions from the attendees. Table 5-2 below provides the questions and responses from Hudbay and AECOM.

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Table 5-2: Other Discussion at the May Public Information Session

Questions Answers (from Hudbay/AECOM) More information found in:

How come it took from 2015 from the purchase of the mill to 2018 to open the mill?

A lot of upfront work was required, including work to understand the gold resource in Lalor Mine and consider alternatives for processing.

Information about the project planning process can be found in Section 1.5.

When the mill is up and running, where will the water be sourced from?

The previous operator of New Britannia used freshwater drawn from Snow Lake. Hudbay’s operation will use mostly water recycled from Anderson TIA brought to the New Britannia site in the pipeline system described in our PowerPoint presentation.

Water requirements are discussed above in Section 2.9.1 and effects on surface water quantity are discussed below in Section 6.5.1.

How are the pipelines going to be housed?

We will build the pipelines on the surface and bury them under a sand cover. It will be kept flowing so that it doesn’t freeze in the winter. Diesel generators will be used for back-up power.

Details on pipeline construction are above in Section 2.7.

What if there is a spill? [pipeline spill] The pipes will have double containment in sensitive areas like water crossings. The entire length of the pipe will also be equipped with an automated leak detection system, monitored 24/7 at the New Britannia Mill control room.

Mitigation measures that are built in to the design of the Pipeline System are above in Section 2.7.1. Mitigation measures for accidents and malfunction are in Section 6.11.

What will the response time be? [in the event of a pipeline spill]

Very fast response time (minutes). Mitigation measures that are built in to the design of the Pipeline System are above in Section 2.7.1.

How can you confidently say you won’t damage the rest of the road to town [the concern was ore trucks traveling from Lalor Mine to New Britannia]? [PR 392 (between Lalor Mine and the Town of Snow Lake) and Cedar Ave.]

It is difficult to confidently say at this time, but we plan to complete an assessment to evaluate road conditions, speed limits, load capacities, the number of trucks permitted and maintenance required, etc. Upon completion of the planned studies, we will be in a better position to comment on the impact of traffic on local roadways. And we will be able to recommend appropriate mitigation measures.

Mitigation measures for traffic are in Section 6.10.5.

Is there any consideration of a haul road [by-passing the Town of Snow Lake] versus using Highway 392?

Yes, one was looked at, but from both an environmental and construction perspective, it likely isn’t the best option. There is not enough truck density traffic to warrant a second route. There will be an access road along the route of the pipeline to be used by Hudbay personnel to perform pipe inspections and maintenance.

The Traffic Impact Evaluation is attached as Appendix C.

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Was underground haulage considered?

It is not a viable option. N/A.

Are there other ore bodies that can be accessed underground?

Exploration is ongoing in the Snow Lake region.

N/A.

What would the construction phase of the tailings pipeline be?

Not certain. Right now we are in the preliminary engineering phase and the environmental assessment phase. We hope to get environmental approval in 2019. For the Lalor Paste Plant pipeline project, it took approximately 6 months for construction.

Project phases and proposed schedule is above in Section 2.14.

During construction, will there be disturbances to traffic?

Yes, but will be minimal impact to the road.

Mitigation measures for traffic during the construction phase are below in Section 6.10.5.

What if damage occurs to the Snow Creek Bridge with an extra 99 trucks a month because then people can’t get in and out of Snow Lake? Will there be an alternative route?

This concern has been brought up by the Town of Snow Lake Council. We understand that the assessment needs to take the haul route in and out of the town into account. Will need to continue evaluating the bridge as Project planning evolves. It is in our best interest to have the bridge in good working order, as it is our product that will also be going over the bridge to the New Britannia Mill for processing.

Emergency access will be provided by the modular steel bridge (Section 2.7.8) that will be constructed as part of the Pipeline System.

Is there any net benefit to Snow Lake? More taxes? What are the future plans for Hudbay’s Snow Lake camp? One community member expressed that “we need to get kids and families moving into the community.”

When the mill is up and running, there will be an additional 40-50 jobs Construction will bring contractors into town. Hudbay’s Richard Trudeau, having spent a large portion of his life in Snow Lake, reviewed some of the history of working for Hudbay and living in Snow Lake. He reflected that many people working in the mines in the Snow Lake region started out living in a camp, but eventually some purchased homes in the community. He commented that the camp is full right now and that this project may cause the camp to expand. It is possible that some rooms may become dorms so people can stay on their days off, encouraging the idea of moving to Snow Lake.

Socio economic benefits are discussed in Section 4.9.

How many years is “many years”? Proven reserves at Lalor until 2027. Continuously exploring around the Lalor and Snow Lake area. Hudbay has a geologist dedicated to the Snow Lake area and New Brit project We want to extend the life of mine

N/A.

One community member expressed concern about the use of potent

Use of cyanide in gold processing is a well understood, standard practice.

Hudbay’s planned cyanide management practices are

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chemicals [cyanide] at the mill and no permanent doctor in the area. Is HudBay worried about the lack of medical care in Snow Lake with the use of these chemicals?

Practices required for safe management are well documented and will be implemented. All gold mills which use cyanide are required to use safe work procedures when handling cyanide. The S02 cyanide destruction process proposed for Hudbay’s operation is proven to be effective at destroying cyanide. The SO2 process is completely different and a significant improvement over the practice used by the previous operator.

described above in Section 1.1.2. Cyanide destruction is described above in Section 2.5.

How far is the Anderson TIA to Wekusko? Does the TIA contain a “bladder” to prevent contamination? Also mentioned concerns about cyanide leaching to Wekusko and the Town’s drinking water and asked if Jay would drink the water right before it enters Wekusko

Anderson is probably one of the top five studied waterbodies in Manitoba. The water quality in Anderson is monitored and so is the water downstream, along Anderson Creek and Wekusko. How tailings will affect Anderson has also been well studied. We understand Anderson. There is no “bladder”. It is high quality water when released to Anderson Creek. There is also a natural dilution effect once it is in Wekusko. We look at fish in that bay to look at the health of the fish in comparison to other lakes and they are comparable. [For the number of years (40+ (?)) that Anderson has been there, you would expect there to be more impacts]

Information on the potential impacts downstream of Anderson TIA is in Section 6.5.3.

Are you bonded? Manitoba’s legislation requires a Closure Plan be prepared and financial assurance be filed to cover the cost of closure. Hudbay has complied with that requirement.

Closure planning is discussed below in Section 7.2.5.

If we were to take a water sample along Wekusko Lake, can we give it to HudBay to get sampled?

Yes, the Flin Flon lab can test for metals. There are certain parameters the lab in Flin Flon is not able to test for, and certain sampling procedures that need to be followed, but yes.

Water quality results from Wekusko Lake can be found in Section 4.8.2.1.

Did you say Anderson tailings has been closed for four years? If so, is there a bladder? How can it be restarted? I thought if there was a bladder it was closed and could not be restarted?

There have been periods during which there were no tailings discharged to Anderson TIA but the environmental license has been in effect since the beginning of operations and is still valid. In fact, in approving the expansion of Anderson TIA, Manitoba regulators issued an updated, more comprehensive version of the license.

N/A.

What type of license? The original license was in the form of a Clean Environment Commission Order

The type of submission is discussed in Section 1.1.

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and the new version is an Environment Act license.

Why doesn’t the mill take the dirty stuff? [water]

The mill recycles water from Anderson TIA.

Water requirements are discussed in Section 2.9.1.

Instead of taking water from Wekusko, why not take it back [to the mill]?

No water is taken from Wekusko. There is a return water pipe taking the reclaim water back from Anderson back to the mill.


Cyanide Destruction and Ultra-violet Previous owners relied on ultraviolet light to destroy cyanide. It was a good process. We are trying to eliminate cyanide in the tails. Standards have been raised since the last owners. Most cyanide is destroyed before it is released.

Cyanide destruction is discussed in Section 2.5. The reasons why treatment will not be required for tailings are in Section 6.5.3 and in detail in the Water Quality Impact Assessment attached as Appendix J.

Have you looked at a water treatment plant at Anderson Creek before it gets to Wekusko?

If results indicate a water treatment plant is necessary, we will look at this option. But at this time it is not required. We are still reviewing data.

The reasons why treatment will not be required for tailings are in Section 6.5.3 and in detail in the Water Quality Impact Assessment attached as Appendix J.

HudBay announced a new concentrator at the Lalor site in 2011. It’s not built. What’s the rationalization?

Comes down to financing and timing. We had the Stall Mill available, which was a large decision factor. It was too expensive. It just didn’t make sense

N/A.

Why does HudBay pay “in-lieu”, have a 20 mile radius?

- Concerned that HudBay is not paying taxes as it affects the “working man”

It’s always been “in lieu of”. Want to speak to this project. We do not have the information right now to answer this question.

N/A.

How many gallons of freshwater is taken from Wekusko Lake?

No water is taken from Wekusko Lake. Freshwater is taken from Snow Lake.


Where will the water come from for fires [in the Town of Snow Lake]?

There will be a freshwater system. Fire suppression is discussed in Section 6.11.3.

All the [Town of Snow Lake] pipes froze. Have you looked into that?

Yes N/A.

Will the presentation be available online and the questions?

Hudbay will look into this. Can provide the presentation by email. Also, at the completion of the project, the Environmental Assessment will include all the information (presentation and questions included).

Presentations are available in Appendix H.

Question about the New Britannia site and Province of Manitoba Areas. What does Hudbay own vs. what belongs to the Province?

Hudbay owns property with the exception of a few locations that belong to Manitoba: The Arsenopyrite Pile (ARP) has never been owned by Hudbay. The Province of

Figure 6 shows the areas owned by the Province of Manitoba.

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Manitoba owns the pile and has assumed the environmental impact/risk and liability. Manitoba Mines Branch has reclaimed the grass area. The ARP has a potential business venture opportunity. The Province is looking for proposals from any interested parties.

Will Hudbay do the same? Leave a big mess and not clean it up?

The Province will not be assuming responsibility for clean-up of any Hudbay operation. Financial assurance has been set aside for the cost of closure.

Closure planning is discussed below in Section 7.2.5.

Will there be a follow-up in 2019? [couldn’t hear the rest of the question]. Can you put the advertisements in visible places?

Yes, information will be put in very visible places. We will return to discuss the project impacts and baseline work.

Follow up information session was held in December 2018 as described below in Section 5.2.

Why did it take so long to do a public meeting?

We need to develop the project up to a point and study it to a point where we can then apply for a license. There is a magic point where it is too early because we don’t have enough details and information, and a point where it is too late. We tried to pick a time when we had enough information to share, and will have another information session in the fall to provide results from the baseline studies that take place over the summer.

Information about the project planning process can be found in Section 1.5

Will work with local groups for access to trails?

Yes, we will work with groups and will provide access, although it is a balancing act because we also need to consider public safety.

Effects on land and resource use are discussed in Section 6.10.1.

There is a lot of dust on the road from Chisel Lake, what will be done about this?

At this time, we want to take questions related to this project.

N/A.

Why does Hudbay call it New Britannia instead of the Snow Lake mine?

Partially because it is a historical name, everybody knows what New Britannia is It is known as New Britannia in the Environment Act Licence, so we kept it the same to avoid confusion with the regulators

History of the New Britannia Mine is in Section 1.4.1.

What is the remediation and emergency plan if a spill occurs near the creek? How will you detect a spill?

There will be double-walled pipes over the creek crossing. There will also be flow monitors and visual inspections. The pipe will be monitored through technology for early detection The bridge system will have daily inspections by people travelling the pipeline In the event of spill response, shut down.

Mitigation measures built in to the design of the Pipeline System can be found in Section 2.7.1. Mitigation measures related to accidents and malfunctions are in Section 6.11.

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Part of the baseline work will be to get an idea of existing areas so if a spill occurs, we can clean up the area to as natural of a state as possible.

What is the lifetime of a pipe? Decades. It doesn’t seem to wear out. In Flin Flon, it is more mechanical damage than anything (accidental damage).

N/A.

5.1.3 Town of Snow Lake

Hudbay and AECOM met with the Town of Snow Lake Mayor and Council (“the Town”) on May 29, 2018 and December 6, 2018 to discuss the Project and gain feedback. Detailed questions and answers from this meeting are provided in Appendix H.

5.2 Public and Stakeholder Engagement Activities in December 2018

5.2.1 Stakeholder Meetings

5.2.1.1 Town of Snow Lake Mayor and Council

The meeting began with introductions and a brief description of the Project as the Mayor and Council changed in November 2018. Hudbay provided an update on their work with Manitoba Infrastructure to date and their plans to continue to work with them to provide traffic solutions for the Town of Snow Lake. Discussions were as follows:

Table 5-3: Summary of Discussions with Town of Snow Lake Mayor and Council, December 6, 2018

Question Answer

What kind of sampling occurs at the Anderson TIA prior to discharge? Is it grab sampling? Will the Town be made aware of sampling?

Grab sampling occurs in Anderson on a weekly basis so it would not be feasible to alert the Town every time sampling is conducted. Every three years there is an EEM monitoring program where sampling is done in Wekusko Lake and results are compared to a reference waterbody.

Would it be possible to keep the Town informed of the results of water quality monitoring?

The results from the New Britannia Mill baseline study will be available on the public registry. AECOM is also conducting seasonal sampling of Anderson TIA.

Will any tailings go to Birch Lake? No, the Birch Lake Tailings Disposal Facility lacks the capacity to contain tailings from Lalor gold ore and the tailings would have likely required treatment.

Will monitoring continue on Birch Lake? Yes it will continue. How much will you have to raise the dam at Anderson to accommodate the extra tailings from New Britannia?

The upgrades to the Anderson dam were designed to accommodate all tailings from Lalor, including the gold tailings to be produced at New Britannia.

General concerns about traffic: • Bridge is too narrow

Hudbay is working with Manitoba Infrastructure and will pass along suggestions to Manitoba Infrastructure. Hudbay does not own the bridge or the roads, so it will

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Question Answer

• Curves are too narrow, should be widened to make more comfortable

• Adding lights at the bridge could make it difficult for large vehicles to get up the hill

• Road will be damaged from heavy truck traffic

• Hauling during shift change

be a joint effort with them. Hudbay will limit trucking hours for safety (e.g., no trucking during shift change).

What is the road rated? Heard it was only 90,000. The road and bridge should have the same ratings as the road and bridges that the ore trucks currently travel along to get to Flin Flon. Doing due diligence with Manitoba Infrastructure to ensure the bridge meets the appropriate standards.

How long will the double-walled portion of pipe over Snow Creek extend?

The double-walled portion will extend for 500 + m on either side of the creek, still in the detailed design phase. The bridge will allow for one (1) vehicle and provide emergency access.

When will construction start at Anderson? Construction will begin in the 2019 construction season. What is the emergency response plan in the event of a spill at the pipeline?

• There will be an emergency response plan in accordance with our ISO 14001 Environmental Management System.

• Pipe will be double walled and equipped with a leak detection system.

• Clean up will be conducted immediately. • Monitoring will be conducted as required by

regulators. Will you sample at Snow Creek moving forward? Hudbay will consider it. Where will the pipeline go? Referred to map on wall and showed the route. Will you use the tailings for paste? Yes, pumping the tailings directly to Stall Concentrator

will allow some tailings to be used for paste backfill. What is planned for noise suppression? Noise will be controlled at the source as much as

possible. • Crusher will be enclosed and insulated. • Alternate back up alarms for vehicles will be used. • Constructing a sound barrier between the crusher

and Snow Lake Camp is currently being investigated.

5.2.1.2 Town of Snow Lake Chamber of Commerce

Hudbay and AECOM met with the Snow Lake Chamber of Commerce in May 2018 and December 2018, prior to both Public Information Session events. At both meetings, the Chamber of Commerce vocalized their support for the Project as it will provide more jobs in the Town of Snow Lake. The Chamber of Commerce is trying to grow the population of the Town of Snow Lake. The Project will provide approximately 50 full-time positions. The Chamber of Commerce hopes that full-time employees will move to the Town, allowing the need for other Town business services to grow. The Chamber of Commerce discussed some incentive ideas for encouraging people to buy homes in the Town versus staying at the Snow Lake Camp.

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5.2.2 Public Information Session in December 2018

Representatives from Hudbay and AECOM were available to guide participants through the storyboards and answer questions asked by participants. The public information session was well-attended, with 44 participants that signed in, and additional participants that preferred to not sign-in. The public information session gave the public the opportunity to:

• Review Project Information and Project developments since the previous (May 2018) information session.

• Discuss the Project with Project representatives from Hudbay and AECOM. • See how their input at the spring information session was incorporated into the Project.

Materials developed for the event included:

• A PowerPoint presentation delivered by AECOM and Hudbay describing the Project, the environmental assessment process, and results from the environmental assessment.

• Display storyboards (14) describing the Project and results from the environmental assessment. • A feedback form for attendees.

A copy of these materials are attached in Appendix H.

5.2.2.1 Notification Methods

Newspaper Advertisement An advertisement was run in Flin Flon’s The Reminder on November 28, 2018 and December 5, 2018. The advertisement contained the purpose of the event and event details. Copies of the advertisements are attached in Appendix H. Poster Advertisement Posters containing the purpose of the event and event details were posted around the Town of Snow Lake at local establishments (e.g. grocery store, pharmacy, bank, etc.) and at Lalor Mine and Stall Concentrator. A copy of the poster is attached in Appendix H.

5.2.2.2 Public Input Received

A total of 36 feedback forms were received from the attendees at the public information session. To protect the privacy of the attendees, copies of the comment sheets are not provided in this report; however, a sample comment sheet can be found in Appendix H. The following subsections summarize the comments received.

5.2.2.3 Feedback on How People Heard About the Event

Attendees were asked how they heard about the Public Information Session, through the newspaper, word of mouth, poster, or Facebook. Facebook and posters were the most common way people heard about the Public Information Session (14 responses each) followed by word of mouth (13 responses).

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Chart 5-2: How did you hear about the Community Information Session?

Note: Respondents had the option of selecting more than one answer

5.2.2.4 Feedback on Where Participants Reside

In the comment forms, respondents were asked where they resided. They were given the options of Snow Lake, Flin Flon, The Pas, Winnipeg or “Other”. All 36 respondents indicated that they live in Snow Lake.

5.2.2.5 Feedback on Previous Information Session

Respondents were asked if they attended the previous information session On May 29, 2018. The majority of respondents had attended the previous session (69%, or 25 out of 36). This question was followed up by asking if participants felt that the feedback provided had been considered in the environmental assessment/planning process. Of the 25 respondents that had attended the previous session, 14 respondents (64%) felt that their feedback had been considered in the environmental assessment/planning process (Chart 5-3). The majority of respondents (64%) felt that their feedback from the previous information session had been considered.

0

2

4

6

8

10

12

14

16

Newspaper Word of Mouth Facebook Poster

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Chart 5-3: Feedback on Previous Information Session

5.2.2.6 Feedback on Presentation Information

The respondents were asked if they found the storyboards and presentation material to be informative (Chart 5-4). The results were positive, with the majority of respondents finding the presentation material to be somewhat informative (11 of 32 respondents) or very informative (9 of 32 respondents). Only one person found the material to be not informative, while the rest of the respondents were neutral on whether they found the information in the presentation and storyboards to be informative.

Chart 5-4: Feedback on Presentation Information

64

27

5 5

Yes No Somewhat N/A

0

2

4

6

8

10

12

Not Informative Lacking Detail Neutral SomewhatInformative

Very Informative

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5.2.2.7 Feedback on if Questions Were Answered

Respondents were asked if someone was able to answer their questions. 80% of respondents felt someone was able to answer their questions, 10% did not feel their questions were answered, and 10% chose not applicable.

5.2.2.8 Feedback on Project Support

The majority of respondents (79%, or 26 of 33 respondents) support the Project, while only two respondents (6%) did not support the Project.

Chart 5-5: Project Support

Further explanation from respondents that indicated project support:

• “Could be good for Snow Lake depending on local hires and use of camp”. • “I’m a shareholder and a resident so want to see this project go for the good of the company &

the town”. • “New jobs good for any town”. • “Sustainable jobs & future of community”. • “Any economic activity in SL is welcome”. • “It is an excellent project for the Town of Snow Lake and northern Manitoba in general”. • “Hudbay’s success is Snow Lakes success”. • “We need to employ Snow Lake residents”. • “Future of Hudbay is in Snow Lake”. • “Will [be] able to sell houses”. • “It is progress – which Snow Lake very much needs!!”

Further explanation from respondents that did not support the Project:

• “There is no road from the mill that will handle the increase truck” [traffic]. • “There has to be a haul road built and not use our highway thru town”.

Yes No No Preference

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Responses from those who had no preference:

• “It does not seem to have any long lasting effect so far”. • “Only concern is meeting truck on Snow Creek Bridge”.

5.2.2.9 Feedback on Improving the Engagement Process

The final question on the feedback form asked the public what we could do to improve the engagement process (described above in Sections 5.1 ). Thirteen responses were received.

Table 5-4: Feedback on Improving the Engagement Process

Theme Questions/Comments 1 People were happy with the presentation and

engagement process.

“The presentation and engagement process was excellent. Informative with an open floor afterwards to voice any concerns, questions, etc.” “Great job”

2 There was a general feeling of satisfaction with the current engagement process.

“Keep on keeping us informed” “You did fine”

3 The Laurie Marsh Community Hall was used at the spring Public Information Session, but was unavailable to rent during the fall Public Information Session. A couple respondents indicated a preference of using the community hall over the school venue.

“Move meetings back to the community hall”

4 The sound system was indicated to be a room for improvement.

“Better sound system”

5 Having information and results available after meetings was requested.

“Publish results of meeting as before. Answer any questions presented either orally or in writing in a reasonable length of time” “Put out a newsletter as you progress”

6 Having more facts and answers available. “Know more facts”

7 Increasing the frequency of public information sessions

“More frequent information sessions”

8 Other “Consider the residents and effects it will have on them”

5.2.2.10 Additional Comments or Concerns

Respondents had the opportunity to provide additional comments or concerns about the Project. The comments have been organized into themes, and responses to them have been provided below.

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Table 5-5: Additional Comments or Concerns

Topic Specific Concern/Inquiry Response Traffic Haulage road should be

considered. Hudbay is working with Manitoba Infrastructure to find a solution for traffic issues in the Town of Snow Lake. The traffic study for the Project (found in Appendix C) concluded that the existing route would be able to accommodate the additional truck traffic from hauling ore to New Britannia. Mitigation measures that will be implemented can be found in Section 6.10.5.

Concerns about bridge. The Snow Creek Bridge has the same rating as the other two bridges along PR 392 and PR 395 which haul trucks currently travel over to drive to Flin Flon. As described in Section 2.7.8, the modular steel bridge that will be constructed for the pipeline system will provide emergency access for standard vehicles.

Curves along PR 392. Hudbay will continue to work with MI to find traffic solutions for the Town of Snow Lake. The curves on PR 392 are outside of the scope of this Project.

Safety. Safety is Hudbay’s top priority. Mitigation measures discussed below in Section 6.10.5 (traffic) and Section 6.11.4 (transportation accidents) will be implemented to ensure public and employee safety.

Road condition concerns. Maintenance of PR 392 is ultimately Manitoba Infrastructure’s responsibility. Hudbay will continue to work with MI to ensure the road is safe for public use.

Water Water quality downstream of Anderson TIA.

Effects on water quality downstream of Anderson TIA are discussed in Section 6.5.3. The water quality impact study attached in Appendix J provides details on the effect that the New Britannia tailings will have on the Anderson TIA. The results of this study conclude that discharge from Anderson TIA will continue to meet or exceed regulatory requirements (MDMER). Water quality in Wekusko Lake will not be affected by the proposed Project.

Hudbay When will the camp be changed to dorms?

Not relevant to this Project.

Noise and Dust General concerns about noise and dust control.

Mitigation measures for noise and dust can be found in Section 6.6. Appendix D contains the air quality assessment and Appendix E contains the noise impact assessment.

5.2.2.11 Other Discussion

Following the PowerPoint presentation there was a formal question and answer period.

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Table 5-6 provides the questions and answers given.

Table 5-6: Other Discussions at the December Public Information Session

Question Answer More Information Found in:

Do you have any plans to construct passing lanes [on PR 392]? With one ore truck every 20 minutes, the roads will get beat up.

We are aware that passing on PR 392 is an issue. If passing lanes are installed, it will happen outside of this project.

The Traffic Impact Evaluation is attached as Appendix C.

Will truck traffic increase on highway 39?

Yes, because more copper concentrate will be produced at the New Britannia Mill which will need to be shipped to Flin Flon.

Traffic generated by the Project is discussed above in Section 2.11. The Traffic Impact Evaluation is attached as Appendix C.

How will the [Lalor] mine increase production to extract enough ore to keep the Stall Concentrator (4,500 tpd base metal ore) and New Britannia (1,500 tpd gold zone ore) operational? Is there a system to keep the two types of ore separate?

We are still in the planning stages and determining how much gold ore can be extracted and what the production rate will be. We are trying to avoid extracting from the gold zones until New Britannia is operational because Stall does not have the equipment or capacity to process it. The ore is kept in separate piles underground.

N/A.

Do the curves in the road [PR 392] meet MI’s current standards? According to MI, only 4/28 of the curves on PR 392 meet current standards. Safety concern related to the bridge.

There is a potential to improve safety. We are working with MI to find solutions.

The Traffic Impact Evaluation is attached as Appendix C. Mitigation measures related to traffic are discussed below in Section 6.10.5.

How many gallons of water will come from Snow Lake? How much water will be used for each mill? What is the pH in Wekusko Lake? There should be a separate hauling road into town.

Water balance is a work in progress. 90% of the water used at New Britannia will be recycled process water from Anderson TIA.

Water requirements are discussed above in Section 2.9.1 and the effect on surface water quantity is discussed below in Section 6.5.1. Data from aquatic field studies is available in the Aquatic Technical Data report attached as Appendix F. The Traffic Impact Evaluation is attached as Appendix C. Mitigation measures related to traffic are discussed below in Section 6.10.5.

Do you test the water from Anderson before it goes into Wekusko? Have you considered a bladder system?

We monitor water quality in Anderson almost daily. We complete EEM monitoring as per our federal requirements every 3 years. We have a very good understanding of what we discharge into Anderson Creek. There is a low permeable layer that protects downstream, there is no reactive

Effects on water quality downstream of Anderson TIA are discussed below in Section 6.5.3 and in detail in the Water Quality Assessment attached as Appendix J.

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Question Answer More Information Found in:

potential for the water that seeps through that layer. A bladder is not necessary with the low permeability layer.

[Concerns about noise] What will the hours of operation be? What hours are better for trucking?

We will be constructing a sound barrier to mitigate the potential impacts on residents of the camp. Crushing will only occur during “daylight” working hours, same as trucking. The mill will operate 24 hours.

Noise is discussed above in Section 2.12.1.2. Noise mitigation measures are discussed below in Section 6.6.3. Detailed Noise Impact Assessment is attached in Appendix E.

Something needs to be done about the “mess” on the road. Snowmobile club would like more information, they use portions of the ROW and need to know what you’re doing.

Yes, we understand something needs to be done about traffic. We can provide updates as there are project milestones.


Will trucking stop during shift change [at Lalor mine]?

Yes. We will not truck during shift change when there is high employee traffic on the roads.

Mitigation measures related to traffic are discussed below in Section 6.10.5.

It is good that this is going ahead but why not put a haulage road in? If you need a road along where you transport tailings, just put in a haulage road there. Concerned about kids playing [outside of the school]. Why don’t you want to build a road?

We explored this option in our assessment. There are construction constraints along the corridor (bedrock outcrops, low lying marshes) that would have a greater environmental impact. It is more permanent infrastructure.


Would there be a certain clearance you must have between the Hydro ROW and the road?

Yes. We have an agreement with Manitoba Hydro to run the pipeline alongside their ROW.

The agreement with Manitoba Hydro is attached in Appendix B.

Will there be any exploration activities north of New Britannia?

Yes, there are exploration plans. N/A.

Will you remediate Birch Lake? BLDTF may still be used again depending on what kind of ore is discovered in our exploration efforts. We will continue to treat it.

N/A.

Do you get the same amount of cyanide in Anderson as Birch?

The S02 cyanide destruction process proposed for Hudbay’s operation is proven to be effective at destroying cyanide. The SO2 process is completely different and a significant improvement over the practice used by the previous operator. Therefore there will not be the same amount of cyanide in Anderson as Birch.

Hudbay’s planned cyanide management practices are described above in Section 1.1.2. Cyanide destruction is described above in Section 2.5.

Would the New Britannia Mill be capable of processing the existing arsenopyrite pile?

The ARP belongs to the Province of Manitoba. At this time it is not viable to process.

N/A

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5.3 Indigenous Engagement

Based on Government of Manitoba and Federal sources, there is no Indian Reserve, Registered Trap Line (RTL) zone associated with First Nation/Aboriginal community use or other Aboriginal interest located within the Project Region (10 km area around the Project Site which signifies the furthest potential impact of the Project, as shown on Figure 5). The New Britannia Mill site is a wholly developed operational site, which has been an active mining operation since 1948. Similarly, the end of the Pipeline System is within an active area that is occupied by Hudbay’s Stall Concentrator. The area in between the New Britannia Mill site and the Stall Concentrator, to be occupied by the Pipeline System, lies within the area subject to Town of Snow Lake By-law which, for reasons of human safety, prohibits hunting to all except registered trapline owners. For these reasons, at the outset of the planning process, it did not appear that the Project would require occupation of lands currently used for traditional purposes by Indigenous peoples. In addition, Hudbay and AECOM included in the environmental assessment team, traditional knowledge holders (as described above in Section 4.2) with expertise in identifying resources which could be of interest for traditional uses. The information gathered in this manner was used to draw conclusions in the environmental assessment process.

5.3.1 Hudbay’s Relationship with Indigenous Communities

Hudbay carries out ongoing education and information sharing in two ways:

• Firstly, in accordance with the Truth and Reconciliation Commission Call For Action, each year Hudbay holds cultural awareness workshops for its employees such as: Mino Pimatisiwin (sweat lodge ceremony) and educational sessions addressing the history of residential schooling.

• Secondly, an ongoing program of outreach to indigenous communities in closest proximity to Hudbay’s facilities (displayed on Figure 17), to share general information about the mining industry, exchange information about employment and business opportunities, and build capacity within Hudbay and the communities to share knowledge on exploration and environment.

A log of the Hudbay workshops and outreach activities held during 2018 is attached in Appendix I.

5.3.2 Engagement Activities for the Proposed Project

For the purposes of the proposed Project, Hudbay and AECOM contacted the following communities to request that they receive and share any information that might be relevant to the Project planning process:

• Opaskwayak Cree Nation (OCN). • Mathias Colomb Cree Nation (MCCN). • Mosakahiken (Moose Lake) Cree Nation (MCN).

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OCN and MCN were selected because of their proximity by road to the Project Site. MCCN was selected because in the course of planning earlier projects, it had expressed interest in the Project Region (see for example Section 8 of the Lalor Mine Environment Act Proposal). A record of the communications with these communities is attached in Appendix I together with copies of written correspondence. AECOM and Hudbay scheduled two meetings with OCN, MCCN and MCN. A PowerPoint presentation was prepared for this meeting and is attached in Appendix I. The first meeting was scheduled in August, 2018. An invitation was issued to each of the Chiefs by means of telephone, personal communication, e-mail, or fax. August 24 was confirmed by all three communities for a meeting in OCN (immediately adjacent to The Pas). Unfortunately, no representatives from these communities attended.

The second meeting was scheduled in OCN at the Kikiwak Inn on December 5, 2018. The meeting was well-attended by approximately 40 people, including a teacher and students from Oscar Lathlin Collegiate Land Based Program and members of all three communities, including councillors from MCN and MCCN and elders from MCCN.

A PowerPoint presentation (attached in Appendix I) was delivered by Hudbay and AECOM. The presentation included a project description, summary of environmental studies completed, and preliminary results of the environmental assessment. Hudbay and AECOM explained the environmental assessment process, including the role of traditional knowledge holders in the field work, and asked for feedback from attendees on any known resource use by their communities in the proposed Project Area. They also were asked to indicate if they had any environmental concerns related to the proposed Project.

Following the presentation, the floor was opened up to questions, feedback, comments, and answers. The following table provides a summary of the questions asked and responses given.

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Table 5-7: Summary of Discussions at OCN Meeting

Question Answer Where does the water from Snow Lake [grey water from the New Britannia Mill, tailings, processing facility] go after it used?

Grey water will be held in storage tanks and pumped out by a licensed contractor as required. Process water, which is sourced from Anderson TIA, will be recycled throughout the mill as much as possible. If discharge is required, it will be discharged into Anderson TIA.

Will there be any discharge into Snow Lake? No. Some fresh water from Snow Lake will be used for processing.

Where do tailings go into the water? At the Anderson TIA, the licensed tailings storage facility which is owned and operated by Hudbay.

Do you test the fish in the tailings facility? No, fish testing is only done downstream of Anderson TIA.

Would you drink the water downstream from the tailings?

People drink water from Wekusko Lake, which is downstream of Anderson TIA. It is not recommended that you drink untreated water, regardless of the tailings storage upstream.

Do you test fish downstream and upstream of the Anderson TIA? What is the difference between downstream and upstream?

We test fish tissue downstream of Anderson TIA and compare the results to a reference Lake (Tramping Lake). We only test fish tissue downstream of Anderson TIA because there are no waterbodies upstream of Anderson in that watershed.

Do you test birds? No, because birds are mobile and could be affected by any number of factors, not just the discharge from Anderson.

How much tailings will be produced by the New Britannia Mill? What will they be like?

We conducted a water quality study and determined that the tailings from the New Britannia Mill will not adversely affect the water quality in Anderson TIA. Exact amount of tailings will be available in the application on the public registry.

Will there be potential employment/contracting opportunities for First Nations?

Yes there will be opportunities. As with all of our projects, there will be a bidding process for contracting opportunities.

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6. Environmental Assessment and Mitigation Measures

6.1 Effects Assessment Methodology

This section contains the results of the environmental assessment. Based on a thorough understanding of the components of the proposed Project (outlined in Section 0 of this application) and detailed study of the existing environment (as described in Section 4), including the information and advice supplied by traditional knowledge holders, AECOM applied professional judgement to determine the potential for each component of the proposed Project to interact with each environmental component (presented in Table 4-1 above). In terms of the environmental assessment team’s study of the existing environment, as described above in Section 4.6.2, the study team ground-truthed (walked and observed) the entire length of the proposed Pipeline System route, with the exception of the southern portion of Segment 2 along Manitoba Hydro Corridor P18H, which was added to the Project description after field work had been completed. Based on extensive experience in the Project Region, however, it is AECOM’s judgement that the environment along the southern portion of Segment 2 will be shown to be substantially similar to the portion of Segment 2 that lies along Manitoba Hydro Corridor HS15. The conclusions set out in this Section are based upon this professional judgement, but further field studies are planned for spring 2019. If the results differ, a further submission will be completed. The assessment includes any effects on social components caused by residual adverse environmental effects. The assessment also takes into account mitigation measures that have been incorporated as design aspects in the proponent’s proposed plan, as well as environmental protection practices and procedures included in the proponent’s standard of operation (such as compliance with International Organization for Standardization (ISO) certified safety and environmental management systems). The assessment includes AECOM’s assessment of the sufficiency of such measures and recommendations for any additional measures which, in our view, would be advisable. Significance of effects is commented on where applicable regulatory criteria exist. In the absence of such criteria, AECOM has provided an overall characterization of the impact taking into consideration the magnitude, reversibility, direction (positive, neutral or adverse), duration and frequency of the effects. Environmental effects that may be caused as a result of accidents and malfunctions are discussed separately in Section 6.11. Definitions of the terms used to guide the effects assessment are provided in Table 6-1.

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Table 6-1: Terms Used in Effects Assessment

TERM DEFINITION Project Phase: Refers to the phase of the Project as construction, operation and maintenance

(“operation”), or closure. Potential Effect: Potential change that the proposed Project may cause the environment Magnitude of Effect: Refers to the estimated percentage of population or resource that may be affected by

activities associated with the construction, operation and closure of the proposed Project. Where possible and practical, the population or resource base has been defined in quantitative or ordinal terms (e.g., hectares of soil types, units of habitat). Magnitude of effect has been classified as less than (<) 1%, 1% to 10%, or greater than (>) 10% of the population or resource base. Where the magnitude of an effect was determined as virtually immeasurable and represented a non-significant change from background in the population or resource, the effect was considered Negligible. An exception to this is in terms of potential human health effects where, for example health issues due to water-borne diseases amounting to 1% of the population being affected would still be considered major. Negligible (immeasurable)

Minor (<1%)

Moderate (1 to 10%)

Major (>10%)

Direction of Effect: Refers to whether an effect on a population or resource is considered to have a positive, adverse, or neutral effect. Positive Adverse Neutral

Duration of Effect: Refers to the time it takes a population or resource to recover from an adverse effect. If quantitative information was lacking, duration was identified as short term (<1 year), moderate term (1 to 10 years) and long term (>10 years). Short term (>1 year)

Moderate term (1 to 10 years)

Long term (>10 years)

Frequency: Refers to the number of times an activity occurs over the Project phase and is identified as once, rare, intermittent or continuous. Once Rare Intermittent Continuous

Scope of Effect: Refers to the spatial area potentially affected by the effect and categorized as Project Site, Project Area or Project Region as defined in Section 2.3. Where possible, quantitative estimates of the resource affected were provided. Project Site Project Area Project Region

Reversibility: Refers to the extent to which an adverse effect is reversible or irreversible over a ten-year period. Reversible Irreversible

Residual Effect: A qualitative assessment of the residual adverse effect remaining after implementing appropriate mitigation measures. Negligible (immeasurable)

Minor (<1%)

Moderate (1 to 10%)

Major (>10%)

6.2 Topography

The New Britannia Mill site and the end of the Pipeline System in the Stall Concentrator/Anderson TIA site are both sites currently occupied by mining operations. None of the construction or operation activities are expected to entail new impact to topography.

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Magnitude of Effect: Negligible Direction of Effect: Neutral Duration of Effect: Long term Frequency: Once Scope of Effect: Project Site Reversibility: Irreversible Sources of changes to the Project Site topography are clearing, trenching, and stockpiling of materials during the construction of the Pipeline System. In addition, levelling will be required in order to construct the access road and to install the Pipeline System to allow for proper site drainage. Segment 1 of the Pipeline System is within Hudbay property in areas that have been previously disturbed. As described in Section 2.8.2, Segment 2 tracks an existing linear feature (Manitoba Hydro ROW). The new Truck Access Road will use the existing access road located east of the Snow Lake Camp (previously disturbed). Some additional clearing, trenching, levelling and stockpiling of materials will be required to upgrade the existing gravel road. The changes in topography as a result of construction, operation and closure of the Project Site are assessed to be Negligible when taking into account the following:

• Wherever practicable, existing access roads and laydown areas will be used in order to minimize changes to topography.

• Segment 1 consists of previously disturbed areas and therefore minimal clearing and levelling will be required.

• The closure phase will include restoration of any changes to topography of the site to match the pre-construction condition of the surrounding area to the extent practical. The Closure Plan for the Project Site will be updated to include the closure activities associated with the proposed alteration.

Overall, the residual impact on topography caused by the Project is assessed to be Negligible. The change in topography, while permanent will impact features which are limited to the Project Site and are common to the Project Region.

6.3 Soil

The New Britannia Mill site and the end of the Pipeline System in the Stall Concentrator/Anderson TIA site are both sites currently occupied by mining operations. None of the construction or operation activities are expected to entail new impact to soil.

6.3.1 Erosion

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Moderate Term Frequency: Continuous Scope of Effect: Project Site Reversibility: Reversible

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Activities that can result in elevated erosion potential are clearing, grubbing, excavating, levelling and vehicle traffic. High wind and precipitation events also can lead to soil erosion, which can consequentially affect other components of the environment including air quality, water quality and vegetation. The effect on soil erosion is assessed as Negligible when taking into account the following mitigation measures and controls:

• Segment 1 and the new Truck Access Road consists of previously levelled and disturbed areas and therefore minimum clearing and levelling will be required.

• Any activities that occur near culverts or other watercourses along the route will be carried out in accordance with applicable DFO’s “Measures to Avoid Causing Harm to Fish and Fish Habitat” or other applicable standards.

• Erosion and sediment control (ESC) measures will be in place to prevent the generation and movement of sediment-laden water.

• Excavated materials will be stockpiled, compacted and reused where appropriate. Stockpile heights will be monitored and limited.

• Excavation activities will not occur during high rain or wind events, to minimize the erosion potential of exposed soils.

At the time of closure, the Closure Plan for the Project will be strictly followed to ensure that required closure procedures associated with the proposed alteration are carried out.

6.3.2 Soil Compaction and Mixing of Soil Horizons

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Moderate Term Frequency: Once Scope of Effect: Project Site Reversibility: Reversible As a result of incidental vehicle and heavy equipment movement, along with excavating, levelling, grading and stockpiling of materials at the Project Site during construction, there is the potential to cause soil compaction and mixing of soil horizons, which may change the soil structure. Soil compaction also has the potential to change the surface drainage patterns and reduce flora growth. As indicated in Section 6.2, Segments 1 is in a previously disturbed area and will not require laborious clearing and levelling. This also applies to the upgraded Truck Access Road as some additional clearing and levelling will be required. Segment 2 is located on undisturbed land that runs approximately parallel to the existing Manitoba Hydro ROW. Clearing and levelling will be required on Segment 2. However, the effects of the Project on soil compaction and mixing of soil horizons are expected to be Negligible due to the following mitigation measures:

• Construction equipment and vehicle traffic will be limited to designated areas within and around work areas, including construction laydown areas at the Project Site.

• Construction activities will be limited during periods of severe precipitation and runoff. • Disturbed and exposed areas will be kept to a minimum with site restoration occurring as soon as

is practical. • Disturbed areas will be re-vegetated following site closure.

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6.3.3 Materials and Waste Management

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Site Reversibility: Reversible Wastes such as used oils, rags, drums and miscellaneous refuse can potentially affect soil quality, which can in turn affect other environmental components (e.g., vegetation, groundwater, and surface water). The impact on soil quality from wastes is assessed to be Negligible because Hudbay’s waste management practices will be followed:

• Wastes generated during construction will be collected in garbage bins maintained at specific locations throughout the Project Site. The bins will be emptied on a regular basis for recycling and/or disposal at a licensed waste disposal facility.

• Waste oils and other hazardous materials generated (chemicals, reagents, waste oil, lubricants, or petroleum products) will be stored in secured containers equipped with spill containment. These materials will be removed by a licensed hazardous materials handler for appropriate disposal or recycling.

6.3.4 Overall Impact to Soil

The mitigation measures listed above to minimize the impact on soil (due to erosion, soil compaction and mixing of soil horizons and materials and wastes) are deemed sufficient. Therefore, the overall residual impact on soil as a result of the Project is assessed to be Negligible.

6.4 Groundwater

Magnitude of Effect: Negligible Direction of Effect: Neutral Duration of Effect: Short term Frequency: Rare Scope of Effect: Project Site Reversibility: Reversible Activities such as fuel handling, lubricants and waste can potentially affect groundwater quality due to leaks, spills and accidents. The transportation of tailings, copper concentrate and return water via the Pipeline System may also potentially affect groundwater quality in the event of an accidental release. The overall effect on groundwater quantity and quality is assessed to be Negligible for the following reasons:

• There are no proposed underground works involved with this Project. • No withdrawals of groundwater are required for the proposed Project and in any case there is no

concern about quantity of groundwater because there are numerous pathways for groundwater recharge.

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• The mitigation measures included in the project design (Section 2.7.1) and those identified in Section 6.11 (Accidents and Malfunctions) and Section 6.3.3 (Materials and Waste Management) are assessed to be adequate to prevent potential effects on groundwater.

6.5 Surface Water

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Site Reversibility: Reversible Surface water quality has the potential to be impacted by the Project due to erosion, materials handling, and waste management. Surface water quantity may be affected by water withdrawal Changes in surface water quality can affect aquatic resources in downstream waterbodies, which can have consequential effects on recreational, subsistence or commercial fishing. Potential effects of Accidents and Malfunctions are addressed in Section 6.13, potential effects on Aquatic Resources are addressed in Section 6.7 and potential effects on Resource Use are addressed in Section 6.10.1.

6.5.1 Water Withdrawal

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Area Reversibility: Reversible The withdrawal of water from waterbodies to supply freshwater to the New Britannia Mill has the potential to adversely affect water levels in these waterbodies. Under the previous operator, most of the water used for processing was freshwater sourced from Snow Lake. As described in Section 2.9.1 and shown on Figure 12, most of the water (approximately 90%) required for processing at New Britannia Mill will be recycled water from Anderson TIA or process water that is recycled within the mill itself (Section 2.5). A minimal amount of freshwater from Snow Lake will be used for domestic purposes and reagent mixing. For these reasons, the impact to surface water quantity is deemed to be Negligible.

6.5.2 Surface Water Quality along the route of the Pipeline System

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Rare Scope of Effect: Project Region Reversibility: Reversible

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Surface water quality along the route of the Pipeline System could potentially be affected by various construction activities such as clearing or excavating. A portion of the Pipeline System will cross Snow Creek via a modular bridge as described in Section 2.7.8. The potential impact to surface water quality in waterbodies along the Pipeline System (Snow Creek) is assessed to be Negligible during construction when taking into account the mitigation measures that will be followed:

• To prevent potential effects on surface water quality during construction, all physical activities near Snow Creek will be carried out in accordance with DFO’s “Measures to Avoid Causing Harm to Fish and Fish Habitat.’’

• Implementation of the measures to mitigate soil erosion (Section 6.3.1).

During operation, surface water quality along the Pipeline System could be affected by accidents and malfunctions. Mitigation measures, as described in Section 2.7.1, have been built in to the Pipeline System design to prevent spills and leaks. Additional mitigation measures are described in Section 6.11.2 below (Spills and Leaks). With the implementation of these mitigation measures, the effect of surface water quality due to accidents and malfunctions is assessed to be Negligible.

6.5.3 Tailings Deposition

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Region Reversibility: Reversible As indicated in Section 2.13.2, tailings from New Britannia Mill will eventually be deposited in Anderson TIA, via the Stall Concentrator. As described in Section 2.5 above, the New Britannia Mill uses a cyanide leaching process to extract gold from ore. This process is different from the flotation process that is currently used at Stall Concentrator, which does not require the use of cyanide. The cyanide leaching process utilizes different chemicals which can result in a different composition of tailings. The cyanide destruction process described in Section 2.5 will destroy most of the cyanide before tailings leave the New Britannia Mill. AECOM completed a water quality assessment to determine the effect on water quality of adding tailings from New Britannia Mill into Anderson TIA. The New Britannia Mill Water Quality Assessment memo is included in Appendix J. A key component of AECOM’s water quality assessment was consideration of a study carried out by SGS Canada Inc. (SGS) for Hudbay which included laboratory test work on cyanide-destructed tailings, the report of which, An Investigation into Environmental Characterization of Cyanide Destruct Tailings Samples from the Lalor Lake Deposit (December 7, 2017), is included in Appendix J. The purpose of the SGS environmental characterization study was to assess the geochemical, ARD, and contaminant release potential associated with tailings generated through the cyanide leaching and floatation process. This was accomplished through a series of “bench tests” designed to simulate the cyanide leaching process (New Britannia Mill) and the flotation process (Stall Concentrator) using samples of tailings from Stall Concentrator, copper-zinc ore and gold-bearing ore that was obtained from

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the Lalor deposit, and the chemicals and reagents that will be used in the milling process at New Britannia Mill, including cyanide. The environmental characterization study included the following analyses:

• Elemental analyses. • Shake flask extraction (SFE) analyses. • Pulp ageing tests – aged process water analyses. • Daphnia magna (freshwater invertebrate) and rainbow trout bioassays – acute lethality. • Modified acid base accounting (ABA). • Net acid generation (NAG). • Humidity cell. • Particle size distribution (PSD). • Atterberg limits. • Standard Proctor. • Settling tests. • Consolidation (oedometer).

To summarize the findings of the characterization study, it was determined that the tailings generated at the New Britannia Mill are likely to be potentially acid generating, with negative net neutralization potential and neutralization potential ratio of <1. Results of the SGS Study, December 2017 Based on these analyses, SGS concluded that water chemistry from pulp ageing tests are representative of the tailings water quality. General anions and total metals were analyzed on day 0, 2, 8, 14, 28 and 56. The ageing test results for the tested samples (current Stall Concentrator tailings, Lalor simulated copper-zinc tailings, and Lalor simulated gold tailings) indicated that total fluoride, nitrate, nitrite, aluminum, mercury, cadmium, copper, lead, selenium, and silver concentrations were above the CCME guidelines throughout the 56 day test period. Metal concentrations were generally greatest on day 0 and progressively decreased or became stable over time. The highest metal concentrations on day 0 were considered to be associated with high total suspended solids content. The conventional parameters (such as conductivity, TDS, and nitrates) increased over the test period. Based on the ageing test data provided by SGS, AECOM determined that, even under laboratory conditions, without the benefit of environmental factors, cyanide concentrations will decrease to below the MDMER and CCME limits in between 8 and 14 days of ageing (see Table 5, SGS 2017). Lalor simulated gold tailings were found to be generally higher in metals concentrations than the Lalor simulated copper-zinc tailings. Maximum concentrations of alkalinity, sulfate, cyanide (total and WAD), aluminum, copper, lead, manganese, mercury, selenium, silver, and thallium throughout the test period were higher in Lalor simulated gold tailings ageing test water than that from ageing test water of the Lalor simulated copper-zinc tailings. Thus, the study carried out by SGS allowed AECOM to understand the chemical makeup of tailings immediately following the cyanide leaching and flotation process at the New Britannia Mill and prior to discharge into the Pipeline System.

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AECOM’s Water Quality Assessment Next, using PHREEQC (Parkhurst and Appelo, 1999) modelling software, AECOM developed a water quality model designed to predict water quality in Anderson TIA throughout the period during which New Britannia tailings will be added to Anderson TIA. PHREEQC is a geochemical modelling code that allows identification and quantification of chemical reactions and simulation of one-dimensional transport processes involving solid minerals and aqueous and gaseous phases. PHREEQC is often used for water predictive studies in the mining industry because of the ease with which it can be used to mix waters and specify equilibrium controls. PHREEQC was applied to examine the evolution of geochemistry in Anderson TIA with continued addition of the Lalor copper-zinc tailings from the Stall Concentrator and the expected addition of Lalor gold tailings from New Britannia Mill. Data incorporated in the model included the data obtained from the SGS environmental characterization study (concentrations at Day 0 of ageing tests), historical water quality sampling data and acoustic profiling surveys for Anderson TIA, and the mass balance and water balance assumptions for the Anderson TIA, New Britannia Mill, Stall Concentrator and Lalor Paste Plant as provided by Hudbay. The modelling study considered four stages associated with addition of tailings in Anderson TIA:

• Stage I: prior to addition of tailings derived from Lalor copper-zinc ore (2012 - 2014). • Stage II: addition of Lalor copper-zinc tailings from Stall Concentrator (Fall 2014 - 2018). • Stage III: addition of Lalor copper-zinc tailings from Stall Concentrator and Lalor gold tailings from

New Britannia Mill (2019 – 2025). • Stage IV: addition of Lalor copper-zinc tailings from Stall Concentrator, only, through the mine life

(2026-2031).

Water quality in Anderson TIA was predicted using a PHREEQC model for each year of the time period between 2017 and 2031 (Stage II to IV). A series of geochemical simulations was performed based on the mixing ratios of the different source terms. The final simulated Anderson TIA water quality for the previous year was used as input for the subsequent year. Based on the PHREEQC model results, AECOM drew the following conclusions:

• All parameters will meet the MDMER limits in all years. • The following dissolved metals may exceed CCME or MWQO in one or more years between

2019 and 2027: aluminum, cadmium, copper and selenium. • Fluoride concentrations may exceed MWQO in one or more years between 2019 and 2027. • Cyanide concentrations may exceed MWQO in one or more years between 2019 and 2027. The

predicted elevated cyanide concentrations are primarily due to the Lalor gold tailings. • TSS cannot be predicted using PHREEQC, as it is highly variable and mainly a function of

sampling conditions. Next, AECOM considered the influence of environmental factors that will occur during retention time in Anderson TIA. In the natural environment, cyanide degrades through volatilization, oxidation, biodegradation, photodecomposition and adsorption processes. As noted above, even under laboratory conditions, cyanide will take only 8 to 14 days to degrade to below regulatory limits. Therefore, by the time effluent is discharged from Anderson TIA, cyanide concentrations will be much lower than the modelled results.

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In summary, no additional water treatment will be required at the Anderson TIA final discharge point because:

• The cyanide destruction process to be applied in the New Britannia Mill (described in Section 2.5) will destroy most of the cyanide before tailings leave the New Britannia Mill.

• Even before the effect of natural degradation in the Anderson TIA, none of the water quality parameters will exceed MDMER.

• Degradation in the natural environment (by processes such as ultraviolet radiation (sunlight)) will further break down cyanide complexes and further decrease the residual cyanide concentrations.

• Planned expansion of the Anderson TIA, which will be necessary to accommodate tailings discharged from the New Britannia Mill, will result in an increase in surface area and retention time (with a complete cessation of discharge out of Anderson TIA for at least one year prior to operation of the New Britannia Mill).

Since the effluent will continue to meet MDMER criteria, it is expected that effluent from Anderson TIA that flows into Anderson Creek and further downstream into Anderson Bay of Wekusko Lake will also continue to meet the required water quality guidelines.

Hudbay will continue to implement the following measures to mitigate potential adverse effects on water quality downstream of Anderson TIA:

• Continue weekly monitoring of the effluent discharged from Anderson TIA into Anderson Creek to ensure that it meets MDMER criteria (and therefore the limits laid out under Environment Act Licence No. 3263).

• If any exceedances occur, discharge will be shut off immediately and not resumed unless the water quality returns to acceptable limits.

Thus, the effect on water quality in Anderson TIA, and subsequently downstream in Anderson Bay of Wekusko Lake, is assessed to be Negligible.

6.5.4 Waste Management

Surface water quality has the potential to be affected by improper handling of waste and materials; the risk of this occurring is assessed to be Negligible because of the reasons identified in Section 6.3.3 (Materials and Waste Management).

6.5.5 Wastewater Management

Wastewater generated by the New Britannia Mill includes return water, grey water and sanitary sewage. The effect of wastewater on surface water quality is assessed to be Negligible for the following reasons:

• Design considerations provided in Section 2.7.1 provide mitigation measures for potential accidents related to the return water pipe.

• Measures listed in Section 6.11.2 will be implemented to minimize risks of spills and leaks. • Sewage and greywater will be stored in tanks (described above in Section 2.13.1) and will be

managed using existing licensed treatment facilities. The existing facilities will continue to operate in accordance with the applicable Environment Act licenses/Clean Environment Commission Orders.

• Return water from the mill (Section 2.7.3) will be deposited into the Anderson TIA.

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6.5.6 Overall Impact on Surface Water Quality

The mitigation measures proposed above are sufficient to mitigate potential effects on surface water quality. Residual effects therefore are assessed to be Negligible.

6.6 Atmospheric Environment

6.6.1 Dust

Magnitude of Effect: Negligible to Minor Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Area Reversibility: Reversible Dust and particulate matter have the potential to adversely affect air quality with consequent effects on human health (e.g. respiratory concerns and safety concerns related to impaired visibility on roads) and vegetation (decreased growth due to deposition). Dust occurs primarily during the summer and fall, with greater likelihood for an increase in dust during dry and windy conditions.

Dust may be produced during the construction and closure phases of the proposed Project by activities such as clearing, grubbing, levelling, stripping of topsoil, stockpiling materials, blasting, movement of construction equipment/vehicles and/or employees, and general use of equipment.

The dense vegetation between PR 392 and the existing Manitoba Hydro ROW ranges between approximately 20 m (in the area near the community cemetery) and approximately 450 m just east of the Town of Snow Lake. This vegetation is expected to mitigate wind effects and overall potential dust migration, limiting its effects to the Project Site and the immediate Project Area.

Clearing and soil disturbance of an area of approximately 11.36 ha will be required for the construction of the Pipeline System. There is the potential that the final design may entail blasting on a small portion of the Pipeline System ROW (in the bedrock outcrop area north of HS15), which also would contribute to dust.

The new Truck Access Road is located within an active mining site and the entrance to this access road is immediately northwest of the Gardewine truck terminal on Cedar Avenue and is approximately 45 m east of the Snow Lake Camp. Clearing and soil disturbance of an area of approximately 0.37 ha will be required for the upgrade/construction of the new Truck Access Road.

Pipeline System

Dust will be generated by vehicle and equipment movement along the route of the Pipeline System. Section 2.11 outlines the traffic volumes expected during the construction, operation and closure phases. Construction equipment, employee vehicles and material delivery trucks will travel to and from Project Site during the construction and will result in an average increase in daily traffic of approximately two to four vehicles per day. The traffic increase during the closure phase is estimated to be the same as during the construction phase. During the operation phase, each day a vehicle will travel (for the purpose of inspection) along Pipeline System access road which will be unpaved. The effect of dust from traffic during the construction, operation and closure phases at the New Britannia Pipeline System are assessed to be Negligible when taking into account the following:

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• Dust suppression activities, such as the use of approved dust control agents will be undertaken on unpaved roads including the new Pipeline System access road.

• The increase in traffic during construction and closure phases is temporary. • At all times, vehicles will be required to adhere to Hudbay’s speed limits on main roads and

access roads. The same speed limit (or less) will apply to the Pipeline System access road and will be similar to other speed limits on Hudbay access roads of 40 km /hr (or less). The New Britannia Mill site has a speed limit of 20 km/hr, which will continue to be imposed.

• Vegetated buffers will be maintained to minimize the transport of dust generated on the Project Site.

New Britannia Mill (Excluding Truck Access Road)

Dust will be generated by the New Britannia Mill during operation by unloading ore from trucks and stockpiling, scrubbers on the crusher, lime silo stack, conveyors and movement of vehicles. These are described in more detail in the detailed the New Britannia Mill Air Quality Dispersion Modelling Report attached as Appendix D. The results of the air dispersion modeling shows that the maximum concentrations of dust will occur in the immediate area surrounding the New Britannia Mill site, with some offsite migration occurring (most of which can be attributed to the Truck Access Road as discussed below). The extent of offsite migration is illustrated in the isopleths in Appendix A of the Air Dispersion Modelling Report (Appendix D). Note that the results of the air dispersion modelling are based on worst case scenario and do not take into account any mitigation measures. The effect of dust during construction and closure activities at the New Britannia Mill is assessed to be Negligible when taking into account the following mitigation measures:

• Areas to be cleared will be minimized where feasible. • Project components will be situated primarily on previously disturbed areas. • Stockpiled materials will be compacted and re-used, where practicable. Material stockpile

heights will be limited. • Trucks hauling materials will be covered to minimize dust coming off loads. • Re-vegetation of disturbed areas will occur as part of site closure activities and will provide long

term mitigation of dust effects upon completion of closure activities.

The Closure Plan for the New Britannia Mill will be updated to include the above noted activities which are relevant to dust.

The effect of dust from operation of the New Britannia Mill is assessed to be Negligible when taking into account the results of the air dispersion modeling and the following engineering controls:

• Crusher will be enclosed and equipped with a wet scrubber. • Most conveyors will be enclosed. • The lime silo will be equipped with a dust collection system which will be used during lime

offloading.

Truck Access Road

Dust will be generated from the vehicle movement along the unpaved Truck Access Road during operation. The results of the New Britannia Mill Air Quality Dispersion Modelling Report (Appendix D) indicate that the maximum concentrations of dust will occur in the immediate area surrounding the New Britannia Mill site, with some offsite migration. Note that the results of the air dispersion modelling are based on worst case scenario and do not take into account any mitigation measures.

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The effect of dust during construction and closure activities at the Truck Access Road is assessed to be Negligible when taking into account the following mitigation measures:

• Areas to be cleared will be minimized where feasible. • The development of the Truck Access Road will occur primarily on previously disturbed areas. • Stockpiled materials will be compacted and re-used, where practicable. Material stockpile

heights will be limited. • Trucks hauling materials will be covered to minimize dust coming off loads. • Re-vegetation of disturbed areas will occur as part of site closure activities and will provide long

term mitigation of dust effects upon completion of closure activities.

The effect of dust from vehicle movement along the Truck Access Road during operation (approximately 48 trucks per day) is assessed to be Minor when taking into account the following mitigation measures that will be followed:

• Dust suppression activities, such as the use of approved dust control agents will be undertaken on the Truck Access Road.

• At all times, vehicles will be required to adhere to Hudbay’s speed limits on main roads and access roads. The same speed limit (or less) will apply to the Truck Access Road and will be similar to other speed limits on Hudbay access roads of 40 km /hr (or less). The New Britannia Mill site has a speed limit of 20 km/hr, which will continue to be imposed.

• Vegetated buffers will be maintained to minimize the transport of dust generated on the New Britannia Mill site and Truck Access Road.

The Closure Plan for the New Britannia Mill will be updated to include the above noted activities which are relevant to dust.

6.6.2 Air Emissions (excluding dust)

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Area Reversibility: Irreversible Sources of air emissions associated with the proposed alteration include: vehicles and exhausts from diesel construction equipment (general vehicle movement on site, using equipment for grading, placing materials etc.). As described in Section 2.10, approximately 25 pieces of equipment will be required during both the construction and closure phases. Emissions from these are anticipated to be limited to the Project Site and the Project Area. Construction is anticipated to take approximately 12 months beginning in the fourth quarter of 2019. Closure will take place mainly in the summer months, over approximately three year period. As indicated in Section 2.11, it is expected that during construction, on average, a maximum of four (4) vehicles and during operation, a maximum of three (3) vehicles will access public roads in vicinity of the

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Pipeline System. Section 6.10.5 below presents the percentage changes in traffic associated with the Project. During operation, trucks will haul ore from Lalor Mine to New Britannia for processing via PR 395 and PR 392. A detailed traffic impact study is attached as Appendix C and results are discussed further in Section 6.10.5. An average of six (6) to eight (8) trucks per day will haul copper concentrate from New Britannia to Flin Flon. The increase in traffic during operation along public and private roads (e.g. Lalor Access Road, PR 395 and PR 392) is temporary and exhaust emissions as a result of this increase are Negligible in relation to air quality in the Project Area. The effect of equipment and vehicle use on emissions is anticipated to be Negligible as a result of the implementation of the following mitigation measures:

• Vehicles and equipment will be well maintained. • Vehicle idling will be kept to a minimum. • All vehicles used for the Project will comply with Environment Canada’s On-Road Vehicle and

Engine Emission Regulations as required.

6.6.3 Noise and Vibration

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Area Reversibility: Reversible An increase in noise levels at the Project Site and within the Project Area could potentially affect people, wildlife and infrastructure (from vibration) in the surrounding area.

As described in Section 2.12.1.2, an acoustic assessment was carried out to determine the impact of the proposed Project on receptors in the Points of Reception (PORs) in the Town of Snow Lake and along the route of the Pipeline System which could be affected by noise generated during construction and operation. The report is attached in Appendix E, Noise Impact Assessment Report. On the Pipeline System portion of the Project, noise generating activity will occur largely only during construction. On the New Britannia Mill site itself, noise generating activity will occur construction and operation.

A second acoustic assessment was carried out to determine the impact of construction and operation of the New Britannia Mill and related activity on Hudbay’s Snow Lake (Lalor) Camp, which is located on the New Britannia Mill site, and to assist in planning any mitigation measures that might be required. This report, Lalor Camp Acoustics, is attached in Appendix E. The noise assessments were completed based on Project design information available at the time. Although building arrangements have changed from the time that the noise assessments were completed, follow-up analysis confirms that the conclusions and recommendations are still valid.

This section summarizes the criteria that were applied in these reports, the results of the assessments, and the mitigation measures which will be incorporated into Project design, construction, and operation.

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The assessors identified sources of noise and vibration based substantially on the Project description described above in Section 2. Based on the planned equipment use and activities, it was determined that the Project would not be a source of significant vibration and therefore a vibration assessment was not required. The assessments focused on noise effects that could be generated during the predictable worse case of construction and operation at the most affected points of reception.

The assessments took into account requirements set out in the Town of Snow Lake Noise By-Law Number 789/97 and the Guidelines for Sound Pollution ((MEMD 2000) published by Manitoba Sustainable Development, Environmental Approvals Branch, but primarily applied the guidance contained in Health Canada’s Guidance for Evaluating Human Health Impacts in Environmental Assessment: NOISE (Health Canada 2017), because it contains comprehensive guidelines for assessing the impact of noise during both construction and operation.

The assessments modelled sound levels that would be expected during construction and operation and compared the modelled results to applicable guidelines. The modelling also took into account mitigation measures which were included in the Project design and recommended best practices to mitigate adverse noise impacts.

Table 2 and Figure 2-1 in the Noise Impact Assessment Report display the PORs identified for the assessment. The nearest receptors shown in this report are the permanent residences located close to the New Britannia Mill.

Figure 1 in the Lalor Camp Acoustics Report displays the proximity of the Lalor Camp to the New Britannia Mill operation, which is closer than the nearest permanent residences.

Regarding the Pipeline System, the closest human receptor is a residence located south of the cemetery which is approximately 300 m south/southeast of the proposed Pipeline System. There is approximately 160 m of heavily treed forest between this residence and the proposed Pipeline System. The next closest residents to the proposed Pipeline System have approximately 330 m of heavily treed forest providing a buffer.

All construction activities will occur in compliance with the Town of Snow Lake Noise By-Law Number 789/97 which states the following:

“An industrial machine may be operated between the hours of 7 o’clock in the morning and 10 o’clock in the evening, local time, of the same day, provided all reasonable effort is made to minimise the noise produced by means of reasonable operation thereof and the use of such sound minimization as is normally used with such a machine.”

Construction Phase

The effect of noise during the construction phase is assessed to be Negligible taking into account the following mitigation measures:

At the New Britannia Mill site:

• Standard backup alarms will be replaced with broadband alarms for mobile equipment. Along the route of the Pipeline System:

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• In the area adjacent to the residence near the cemetery, standard backup alarms will be replaced with broadband alarms for mobile equipment (shown on Figure 2-2 in the attached Noise Impact Assessment Report).

In addition to the above mitigation measures, the following best practices may also be employed to further reduce the Project’s potential impact:

• Adjust construction activities by modifying equipment usage (e.g., duration or quantity). • Advise nearby residents of major noise-generating activities, and determine if additional mitigation

is required. • Maintain machinery and noise-abatement equipment. • Establish a procedure or protocol that addresses concerns in a timely manner.

Operation Phase

Results of the assessments showed that the following mitigation measures will be adequate for noise to have Negligible adverse effect on receptors in the Town of Snow Lake during operation:

• Flotation and mill building facade construction meeting a minimum sound transmission loss (STC) of 30.

• Delivery of ore and other vehicle traffic limited to daytime hours (7:00-22:00). • Alternative back-up alarms for vehicles. • Vehicles and equipment will be well maintained. • Hudbay provides hearing protection as required to ensure employees working on site are

protected from noise during construction, operation and closure activities. • Construction of a noise barrier between the mill and the Snow Lake (Lalor) Camp (as shown on

Figure 7).

All closure activities will be carried out in accordance with The Workplace Safety and Health Act and the Hudbay Occupational Health and Safety Assessment Series (OHSAS) 18000 certified management system, which will avoid potential effects on health and safety.

6.6.4 Overall Impact on Air

The mitigation measures proposed above are sufficient to mitigate any adverse effects due to dust, emissions and noise and vibration during the construction, operation and closure phases. Residual effects on air quality are therefore assessed to be Negligible.

6.7 Terrestrial Environment

6.7.1 Vegetation

The potential effects on protected and other terrestrial vegetation arise from clearing and the accumulation of contaminants (dust deposition and bioaccumulation).

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6.7.1.1 Clearing

Magnitude of Effect: Minor Direction of Effect: Adverse Duration of Effect: Moderate term Frequency: Once Scope of Effect: Project Site Reversibility: Reversible As noted in Section 2.6 and 2.8, minor clearing will be required in areas along the upgraded Truck Access Road and along the Pipeline System; approximately 0.37 ha and an approximate total maximum area of 11.36 ha, respectively. As the New Britannia Mill site has been previously cleared and no additional clearing will be required for the components located at the New Britannia Mill site, only the vegetation cover along the Pipeline System is considered as part of this analysis. The relevant portion of the Project Site is comprised of a 20 m ROW along the route of the Pipeline System. The impact of clearing on vegetation will be Minor for the reasons described below. Vegetation is Common to the Region The Forestry Branch of Manitoba Conservation Forest Management Units (FMU) contains the most detailed vegetation identification information available for the undeveloped portions of the province. Vegetation cover classes within each FMU are identified by characterizing the species composition based on a hierarchical series of attributes (e.g., land cover, productivity, tree type and species composition). Each cover class identifies a unique area of tree canopy that combines a series of attributes and species composition that can be used to determine a general habitat classification. The cover classes for the Project Area (3,936 ha) and surrounding Project Region (44,489 ha) were determined and were compared to the cover classes to be removed during the Pipeline System construction (11.36 ha) and Truck Access road upgrade (0.37 ha).

The route of the Pipeline System includes a total of seven different cover classes: five vegetated cover classes and one water cover class (illustrated on Figure 18).

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Table 6-2: Cover Classes and Areas

Cover Class Area (ha) of Cover Class % of Cover Class

Project Area Project Region Project Area Project Region

Balsam Fir 8 133 0.21 0.30

Balsam Poplar 12 53 0.31 0.12

Black Spruce 1,167 9,318 29.64 20.94

Jake Pine 465 8,119 11.80 18.25

Tamarack 34 173 0.88 0.39

Trembling Aspen 378 3,672 9.60 8.25

White Birch 10 259 0.25 0.58

White Spruce 91 482 2.32 1.08

Other 573 7,907 14.56 17.77

Shrub 40 223 1.02 0.50

Land clearing 6 7 0.15 0.02

Water 632 12,521 16.06 28.14

Non-vegetated 520 1,621 13.21 3.64

Total 3,936 44,489 100.00 100.00

Notes: Vegetation analysis illustrated on Figure 17.

Based on AECOM’s experience in the Project Region, observations made during the field work carried out in 2018 and professional judgement, it can be expected that each type of vegetation that will be cleared along the route of the Pipeline System is present in the same proportion as it is in the cover types described for the Project Area and Region displayed above in Table 6-2.

Based on the information provided in Table 6-2, the proportion of the cover classes that will be removed represents a small percentage of the overall cover class percentages calculated for the Project Area and Region. These cover classes are common to the area in and surrounding the Project Region. Therefore, the removal of this vegetation will not result in a substantial loss of the overall cover types.

Traditional knowledge holders observed medicinal plants in wetland areas during field studies (discussed above in Section 4.6.3). These wetlands, which are located adjacent to the New Britannia Mill site, will be avoided to the extent feasible. Rehabilitation upon Closure The Project Site will be returned to native conditions to the maximum extent feasible. Once the infrastructure on the site has been removed and the site has been re-graded, disturbed areas will be re-vegetated with native vegetation species in accordance with the Closure Plan. Based on Hudbay mine closure experience in the Snow Lake region, the growth of grasses and mosses is apparent within the first few years following closure, whereas trees and shrubs take longer to establish through natural succession and may be evident within a five to ten year period following closure.

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The success of re-vegetation efforts at the Project Site will be regularly monitored with subsequent re-vegetation occurring as required. Monitoring of re-vegetation efforts will occur on an annual basis until determined by regulators to be successful.

6.7.1.2 Dust Deposition

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Site Reversibility: Reversible Dust generated during the construction, operation, and closure phases of the proposed Project can potentially affect vegetation in the area by interfering with the photosynthetic ability of the vegetation. However, assuming implementation of the mitigation measures above in Section 6.6.1 (Dust), effects on vegetation due to dust are assessed to be Negligible to Minor.

6.7.1.3 Protected Vegetation Species

Magnitude of Effect: Negligible Direction of Effect: Neutral Duration of Effect: Moderate term Frequency: Intermittent Scope of Effect: Project Site Reversibility: Reversible Protected terrestrial species can be impacted by Project activities and components through changes in habitat quality and quantity. The pathway of effect is primarily through indirect effects on other environmental components (such as clearing or dust deposition) and the mitigation measures applied to those components will sufficiently mitigate the potential effect on protected species (Sections 6.7.1.1 (clearing) and 6.6.1 (dust)). Of the species of special concern listed by the Manitoba CDC (Manitoba Sustainable Development, 2016a), only one terrestrial flora species is protected federally under the federal SARA: the Flooded Jellyskin. The federally-protected Flooded Jellyskin (lichen species) is known to occur in the Churchill River Upland Ecoregion; however, the nearest recorded occurrence is approximately 100 km west-south-west of the Project Site (COSEWIC, 2004). No Flooded Jellyskin were observed in the terrestrial surveys undertaken as part of the baseline investigations nor have they been observed in the Project Area during previous environmental surveys conducted by AECOM in the Snow Lake region. It is assessed that Flooded Jellyskin are not likely present within the Project Site. For both these reasons, the residual effect on Flooded Jellyskin is assessed to be Negligible.

6.7.1.4 Overall Impact on Vegetation

For the reasons presented above, the overall residual impact on vegetation (including protected flora species) due to clearing and dust deposition is assessed to be Negligible to Minor.

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6.7.2 Wildlife

Clearing (loss of habitat), noise (disturbance), and vehicle collisions (mortality) are potential sources of effects on protected and other wildlife species.

6.7.2.1 Loss of Habitat

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Moderate term Frequency: Once Scope of Effect: Project Site Reversibility: Reversible Loss of vegetation through clearing can affect wildlife by reducing the amount of habitat available. The potential impact of loss of habitat on wildlife species is assessed to be Negligible for the following reasons:

• As described in Section 6.7.1.1, the cover classes affected by the construction of the Pipeline System and Truck Access Road are not unique to the Project Area. There is an abundance of similar habitat types throughout the Project Region.

• Traditional knowledge holders indicated that the route of the Pipeline System is not a preferred hunting or trapping area.

• Nesting birds that may use edge habitat available along the route of the Pipeline System will be able to continue to use this habitat following the development of the Project.

• No clearing will occur in the peak migratory bird nesting season, approximately May 12 to August 5.

• No clearing will occur in the shoulder nesting season (approximately from April 28-May 11 and August 6-20) unless a nest search is conducted by a biologist no more than three days prior to clearing. If a nest is found, an appropriate ‘no activity’ buffer is established (e.g. 60 m) until the nest is no longer active and the young have left the nesting area.

• Clearing will be minimized to the extent feasible.

In accordance with the approved Closure Plan, upon closure the Project Site will be re-vegetated, restoring native conditions to the extent feasible.

6.7.2.2 Noise

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Area Reversibility: Reversible As described above in Section 6.6.3, noise generated during construction, operation and closure phases of the proposed Project has the potential to disturb wildlife within the Project Area. During construction, noise will be generated to varying degrees as described above. The potential impact of noise on wildlife is assessed to be Negligible taking into account the mitigation measures in Section 6.6.3 and the following:

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• It is anticipated that local wildlife are likely already accustomed to some level of noise based on the existing activity in the area (e.g. Snow Lake Camp, PR 395, PR 392 and the Stall Concentrator).

• If local wildlife are deterred from the Project Site, it is not anticipated that this will substantially affect wildlife as similar habitats are available in the Project Area and Project Region.

• The duration of the effect is short-term, considering construction of the Pipeline System will occur during one year.

6.7.2.3 Risk of Vehicle Collisions

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Site Reversibility: Reversible With the anticipated increase in traffic on local public roads (discussed in more detail in Section 2.11), there is potential for increased risk of wildlife collisions. Wildlife (e.g. Moose, deer) may pass through the Project Area, including across provincial highways and local roads. The potential risk of vehicle collisions with wildlife as a result of the Project is assessed to be Negligible for the following reasons:

• As local wildlife populations are considered low, the potential for increased wildlife collisions is also considered low.

• Hudbay’s experience in the local area indicates that wildlife collisions are rare. Any collision with a Hudbay or contractor vehicle would have to be reported in Hudbay’s system. The records contained in the system have been reviewed back to 2012, and the system contains no such reports.

• Speed limits on access roads, local roads and Provincial highways will continue to be implemented.

6.7.2.4 Protected Wildlife Species

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Moderate term Frequency: Once Scope of Effect: Project Site/Area Reversibility: Reversible Protected wildlife species can be impacted by Project activities and components through changes in habitat quality and quantity. The pathway of effect is primarily through indirect effects on other environmental components (e.g. vegetation clearing, disturbance due to Project construction activities). Measures that will be applied to sufficiently mitigate potential effects on protected species are included in Section 6.7.1.1 (clearing) and Section 6.7.2.1 (loss of habitat). Section 4.5 describes the protected wildlife species that may occur in the Project Region and probability of occurrence at the Project Site. The potential impact of the proposed Project on protected wildlife species is assessed to be Negligible for the following reasons:

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• The Project Site is a largely previously disturbed area (e.g. mining operations, Manitoba Hydro transmission line corridor) and provides very limited ideal habitat for protected wildlife species.

• Mitigation measures identified in Section 6.7.1.1 (clearing) and Section 6.7.2.1 (loss of habitat) will be applied for protected wildlife species.

6.7.2.5 Overall Impact on Wildlife

For the reasons outlined above and primarily due to the previously disturbed and ongoing activity within the Project Site and availability of alternative wildlife habitat in the surrounding Project Area and Region, the residual impact on wildlife is assessed to be Negligible.

6.8 Aquatic Resources

Effects on aquatic resources occur primarily through changes in habitat quality or quantity. Reduced quantity and quality of habitat can reduce the abundance, diversity or community composition of aquatic resources, with secondary effects on organisms higher in the food chain. Habitat quality may be affected by changes in surface water quality, surface runoff (elevated concentration of metals or other contaminants), air dispersion (dust) or any accidental leaks or spills during the construction phase of the Project. Habitat quantity can be reduced through direct changes in habitat caused by construction activities.

6.8.1 Fish and Fish Habitat

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Moderate term Frequency: Continuous Scope of Effect: Project Site/Area Reversibility: Permanent The proposed alteration does not require undertaking any activities in or near Snow Lake; therefore, there will be no effect on fish or fish habitat in Snow Lake. There is no fish or fish habitat at the New Britannia Mill site or at the end of the Pipeline System (the site of the Stall Concentrator). The only waterbody within the Project Site is Snow Creek. The Pipeline System will cross Snow Creek via a modular steel bridge (Section 2.7.8). Some riparian vegetation will be cleared to construct the Pipeline System which may result in a potential loss of habitat at the proposed water crossing. The effect on fish and fish habitat is assessed to be Negligible for the following reasons:

• Snow Creek does not appear to support sensitive or unique fish habitat at the proposed water crossing.

• Clearing of riparian vegetation will be minimized to the extent feasible. • Riparian vegetation (coniferous mixed-wood forest, as described above in Section 4.8.2.7) is

common throughout the assessed length of Snow Creek and the amount to be cleared (approximately 20 m by 20 m) is small given the length of the Creek (approximately 6 km).

• No fish Species at Risk were observed during aquatic surveys. • Any activities that occur near Snow Creek will be carried out in accordance with applicable DFO

“Measures to Avoid Causing Harm to Fish and Fish Habitat” or other applicable standards.

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• No component of the Pipeline System (i.e. the modular steel bridge) will be constructed below the high water mark. The bridge will be a clear-span structure, support on abutments placed above the high-water mark. No instream works are anticipated to be required.

• Mitigation measures built in to the Pipeline System design (Section 2.7.1) will mitigate the risks of any spills or leaks which could have an effect on fish and fish habitat.

• There are no physical activities that are anticipated to affect fish or alter fish habitat downstream of Anderson TIA. Water quality downstream of Anderson TIA will not be affected by the Project. Fish habitat downstream of Anderson TIA is therefore not expected to be affected.

The mitigation measures outlined above and identified in Section 6.3 (soil), Section 6.6 (air), and Section 6.11 (accidents and malfunctions) are sufficient to prevent potential effects on fish and fish habitat.

6.8.2 Lower Trophic Level Biota

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Moderate term Frequency: Intermittent Scope of Effect: Project Site/Area Reversibility: Reversible Lower trophic level biota can be affected by a change in surface water quality and habitat disruption. There is a potential for surface runoff and potential spills to adversely affect surface water quality along the route of the Pipeline System. Taking into account the proposed mitigation measures in Section 6.3.1 (soil erosion), Section 6.5 (surface water), and Section 6.11.2 (spills and leaks), the effect on lower trophic biota along the Pipeline System is assessed to be Negligible.

6.8.3 Protected Aquatic Species

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Moderate term Frequency: Rare Scope of Effect: Project Site/Area Reversibility: Reversible Protected aquatic species can be impacted by project activities and components through changes in habitat quality and quantity. The pathway of effect would be primarily through indirect effects on other environmental components (e.g. erosion, surface water quality). It is assessed that the mitigation measures applied to those components are sufficient to prevent the potential effect on protected species (e.g. Sections 6.3.1 (erosion), and 6.5.2 (surface water quality)). As well, it is unlikely that protected species occur in any area which could be potentially affected by the Project. As noted in Section 4.7, no aquatic species were identified to potentially be within the Project Region.

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6.8.4 Overall Impact on Aquatic Resources

For the reasons listed in the sections above, the residual effects on aquatic resources are assessed to be Negligible.

6.9 Climate

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Area Reversibility: Irreversible Sources of greenhouse gas (GHG) emissions associated with the proposed alteration include: vehicle exhausts and exhausts from diesel construction equipment (e.g. general vehicle movement on site, using equipment for grading and placing materials). During construction and closure, GHG emissions are expected to be typical of construction activities and will be limited in duration. During operation, GHG emissions will be limited to vehicle use (as described in Section 2.11). The effect of GHG emissions from the Project is assessed to be Negligible for the following reasons:

• Mitigation measures listed in Section 6.6.2 (air emissions) will be implemented. • The filtration system for copper concentrate at New Britannia will decrease moisture content in

copper concentrate shipped from Northern Manitoba to Canadian or other markets, thereby decreasing the amount of fuel used for transportation by truck and rail.

6.9.1 Overall Impact on Climate

The mitigation measures proposed above are sufficient to mitigate any adverse effects due to GHG emissions. Residual effects on climate are therefore assessed to be Negligible.

6.10 Socio-Economic Effects

6.10.1 Land and Resource Use

Magnitude of Effect: Negligible Direction of Effect: Neutral Duration of Effect: Moderate term Frequency: Continuous Scope of Effect: Project Site/Area Reversibility: Reversible

Land and resource uses and users in the Project Region that may be indirectly impacted include:

• Harvesting and trapping opportunities. • Fishing (recreational, subsistence and commercial). • Recreational use of existing trails.

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• General use of the Project Area and Region.

Hudbay has had discussions with all of the trapline owners identified in Section 4.9.3.1 and shown on Figure 16 as follows:

RTL #13 Russel Bartlett stated that he has no concerns with respect to the proposed Project. Hudbay continues to share information with him concerning current and future Hudbay activities in and near the Anderson TIA. RTL #16 Manitoba Trappers Association advises that RTL #16 is not used for commercial trapping. At this time RTL #16 is used by an organization called the Junior Canadian Rangers, whose goal is to teach outdoor skills to youth in the Snow Lake region. On behalf of the Junior Canadian Rangers, Greg Foord indicated that the proposed Project should not impact their activities. Mr. Foord was encouraged to submit proposals for Hudbay funding for future activities they might be planning in the Snow Lake region.

RTL #22 Wayne Galiz stated that he has no concerns with respect to the proposed Project. He indicated that his partner, Wayne Morozoff, may currently be trapping within RTL #22 and provided his contact information. Hudbay is in discussions with Mr. Morozoff to be sure that his trapping is not affected or that he is appropriately compensated for any loss. Hudbay also maintains communication with Mr. Galiz and Mr. Morozoff concerning unrelated exploration work that Hudbay is carrying out in the Snow Lake region. The potential impact on land and resource use is assessed to be Negligible for the following reasons:

• The New Britannia Mill site and the end of the Pipeline System, the Stall Concentrator/Anderson TIA are fully-developed and have been used for mining purposes for decades.

• As presented in this report, residual environmental effects on environmental components have been assessed to be Negligible in magnitude.

• As described in Section 1.6, the area in between the New Britannia Mill site and the Stall Concentrator, to be occupied by the Pipeline System, lies within the area subject to Town of Snow Lake By-law which, for reasons of human safety, prohibits hunting to all except registered trapline owners.

• No activity, component or impact of the proposed alteration will impede access to downstream resources or affect any current user’s ability to continue to exercise any recreational, commercial or subsistence use of these resources.

• All trappers with rights in the Project Area have been identified and all have indicated that they have no concerns. Hudbay maintains communication with these trappers.

• With respect to snowmobile trails, Hudbay has discussed the proposed alteration with members of the Sno-Drifters snowmobiling club. The club has raised concerns related to access to their trails. Similar to other Hudbay Projects, Hudbay will allow access across the Pipeline System in areas of their trails.

• As described in Section 6.8, there will be no impact to Fish or Fish Habitat and therefore no impact on fishing activities.

• Since residual impact on wildlife is assessed to be Negligible (Section 6.7.2.5), there will be no impacts on hunting in the Project Region.

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The proposed Project will not cause any impact on either park or park users as residual environment effects that extend into the Project Region (Wekusko Falls Provincial Park is the only park within the Project Region) have been assessed as Negligible.

6.10.2 Heritage Resources

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short Term Frequency: Rare Scope of Effect: Project Site Reversibility: Irreversible Project activities such as clearing or excavating can potentially affect heritage resources. However, as described in Section 4.7.2, there are no recorded heritage resources at the Project Site and the potential for any to be found is minimal. There will be no disturbance beyond the Project Site. Therefore, the potential effects on heritage resources are anticipated to be Negligible. In the unlikely event that heritage resources are identified, the following measures will be implemented in compliance with Manitoba statutory requirements:

• If artifacts or historical features of skeletal remains are encountered during construction activities, work activities will stop immediately around the affected area with the find reported to the site supervisor. A qualified archaeologist would investigate and assess the find prior to continuation of work.

• If skeletal remains are encountered, the find will be immediately reported to the site supervisor and the RCMP.

6.10.3 Aesthetics

Magnitude of Effect: Negligible Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Site Reversibility: Reversible Project activities during construction and operation could potentially impact the aesthetics of the Project Site. This potential impact is assessed to be Negligible for the following reasons:

• Project components are located in areas that have been previously disturbed as part of the New Britannia Mill, Snow Lake Camp, Stall Concentrator, Anderson TIA, historic mining activities, and adjacent to the Manitoba Hydro ROW.

• The Project Site will be inspected on a regular basis for loose waste and debris in order to maintain a clean site.

• Waste and debris will be stored in bins and removed from the site on a regular basis. • The Closure Plan for the New Britannia Mill will be updated to include the closure activities

associated with the proposed Project. During the closure phase, the Project Site will be re-vegetated and returned to native conditions to the extent feasible.

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6.10.4 Effects on Indigenous Peoples

As noted above in Section 1.4, Hudbay has operated in the Snow Lake district for over 50 years. The Project Site is not located near any First Nations communities or heritage location. Based on Government of Manitoba and Federal sources, the nearest Indian Reserves are located well outside the Project Region. Figure 17 shows the locations of these Indigenous communities relative to the Project Region. Hudbay carried out engagement with these Indigenous communities as described in Section 5.3, which included sharing the Project description and environmental studies, and seeking feedback on any potential overlapping use for traditional purposes. No First Nation or Aboriginal resource (hunting, fishing, trapping) or traditional use that could be affected by the proposed Project was identified during this engagement process or in other public and stakeholder meetings. The New Britannia Mill site is a wholly developed operational site, which has been an active mining operation since 1948. Similarly, the end of the Pipeline System is within an active area that is occupied by Hudbay’s Stall Concentrator. As described in Section 1.6, the area in between the New Britannia Mill site and the Stall Concentrator, to be occupied by the Pipeline System, lies within the area subject to Town of Snow Lake By-law which, for reasons of human safety, prohibits hunting to all except registered trapline owners (none of whom is associated with an Indigenous community). Restrictions with respect to human safety generally apply to all users. With respect to the surrounding Project Region, as assessed in Section 6.10.1, resources which could be used for fishing and hunting will not be affected by the proposed Project. While harvesting of medicinal plants cannot be absolutely ruled out, no such use was identified in the engagement process and habitat conditions where potentially medicinal plants were observed are relatively common in the Project Region. Further, during construction, Hudbay will apply the following mitigation measures:

• These areas will be avoided to the extent feasible. • Hudbay will include in the construction team a traditional knowledge holder who can advise on

areas to be avoided. • Clearing will be carried out under winter conditions when plants are not being harvested.

For all of these reasons, the Project does not appear to require occupation of lands known to be currently used for traditional purposes by Indigenous peoples.

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6.10.5 Traffic

Magnitude of Effect: Minor Direction of Effect: Adverse Duration of Effect: Short term Frequency: Continuous Scope of Effect: Project Region Reversibility: Reversible During the construction and closure phases, traffic will increase by approximately five vehicles per day. During the operation phase, traffic will increase as described in Table 6-3. Trucks will haul ore from Lalor Mine to New Britannia via PR 395 and then PR 392. Trucks will also transport copper concentrate from New Britannia to Flin Flon for further processing via PR 392 (south of PR 393).

Table 6-3: Traffic Changes

Provincial Road 395

Provincial Road 392 North of Provincial

Road 395

Provincial Road 392 South of Provincial Road 393

AADT (MI, 2016)1 630 570 450 Maximum Vehicles - Construction Phase

5 5 0

Percentage Change 0.95% 0.55% to 1.8% 0 Maximum Vehicles - Operation Phase

40 40 15

Percentage Change 6.34% 7.02% 3.33% Notes: 1 The numbers presented represent the range of AADT along the route between the Lalor Mine and Snow Lake. AADT = Annual Average Daily Traffic.

The results of the traffic study in Appendix C show that no additional mitigation measures are required to accommodate the increase in truck traffic. Highway conditions was the most commonly expressed public concern noted during the Public Information Sessions that were held in Snow Lake in May 2018 and December 2018. Hudbay has relayed the concerns expressed by Snow Lake residents to Manitoba Infrastructure. The effect of traffic on the Town of Snow Lake is assessed to be Minor when taking into account mitigation measures described in Section 6.6.1 (Dust) and Section 6.11.4 (Transportation Accidents). Offloading and distribution of copper concentrate produced at both Stall Concentrator and New Britannia Mill will be centralized via the Copper Concentrate Pipeline which will limit the number of trucks on the highways. This is due to the efficiency of dewatering at the mill thus having less water in the final copper concentrate for transport. The synergistic relations between the two facilities has an overall positive impact on the environment by balancing water usage at the facilities.

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6.10.6 Overall Impact on Socio-Economic Environment

For the reasons outlined above, the residual impact on components of the socio-economic environment (land and resource use, heritage resources, aesthetics and Indigenous peoples) is assessed to be Negligible.

6.11 Accidents and Malfunctions

To prevent accidents and malfunctions, all phases of the Project will be conducted in accordance with applicable regulatory requirements. In addition to standard safety controls and procedures (alarm systems, training and operating procedures), the following sections provide additional details on precautionary measures that will be implemented by Hudbay to further minimize the potential for accidents and malfunctions to occur.

6.11.1 Worker Health and Safety

Worker protection in Manitoba is regulated through standards, procedures and training required under The Workplace Safety and Health Act. In addition, all Hudbay operations abide by their internal health and safety requirements as covered under its certified safety management system, OHSAS 18001. Safety training, equipment and personal protective equipment will be provided to employees. Safety equipment, including cyanide antidote kits, will be located throughout the New Britannia Mill and accessible to all employees. Special training in relation to cyanide handling will be administered.

6.11.2 Spills and Leaks

Environmental effects can be caused by spills of fuel and chemicals such as diesel fuel, lubricants, oils and hydraulic fluids. An accidental release of hazardous materials and/or equipment fluids could occur from improper storage and handling procedures. Accidental releases have the potential to affect air, surface water, groundwater and soils, with consequential effects on vegetation, aquatic resources and possible human health and safety. Mitigation measures that have been built in to the design of the Pipeline System are described in detail in Section 2.7.1. In addition, the following Hudbay standard procedures will be employed to prevent spills from occurring during all Project activities:

• Storage of chemicals and reagents used in the New Britannia Mill will follow the requirements outlined in Section 2.9.4.

• Any diesel tanks used on site will be self-contained aboveground storage tank(s). • When servicing requires drainage or pumping of lubricating oils or other fuels from equipment, a

groundsheet of suitable material and size will be spread on the ground to catch all fluid in the event of a leak or spill. An adequate supply of suitable absorbent material and any other supplies and equipment necessary to immediately clean up spills will also be available.

• Storage and disposal of liquid wastes and filters from equipment maintenance and any residual material from spill clean-up will be contained in an environmentally safe manner and in accordance with any existing regulations.

• Waste oils, fuels and hazardous wastes (if any) will be handled in a safe manner. Staff will be required to transport, store and handle all such substances as recommended by the suppliers and/or manufacturers and in compliance with applicable Federal, Provincial and Municipal

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regulations. Manitoba Sustainable Development will be notified immediately if a reportable spill occurs.

• Fuels, oils, or other hazardous materials will be stored only in designated areas. • Hudbay will ensure that fuel handlers are trained and qualified and that appropriate emergency

response measures are in place and readily available. • Storage sites will be inspected periodically for compliance with requirements as applicable. • Investigation and remediation of spills will be undertaken, if necessary. • Remediation of soils, as required, will be undertaken as part of closure activities. • Personnel on site will be trained in how to deal with spills, including knowledge of how to

properly deploy site spill kit materials. • Service and repairs of equipment shall only be performed by trained personnel. • Vehicles and equipment will be maintained to minimize leaks. Regular inspections of hydraulic

fuel systems on machinery will be completed on a routine basis; when detected, leaks will be repaired immediately.

With the implementation of the above mitigation measures as necessary and assuming the implementation of safe work practices, the risk of spills is considered to be appropriately mitigated.

6.11.3 Fires and Explosions

The presence of mechanical equipment, fuels and other hazardous materials creates a potential for fires and explosions. Such incidents can harm on-site personnel, cause equipment damage and lead to a release of contaminants, resulting in consequent effects to other environmental components (air, surface water, groundwater, flora, fauna, aquatic resources and aesthetics). Potential socio-economic effects may occur if a site shut-down is required in the event of a large accident (such as incidents that may require evacuation, disruption of traffic, etc.).

The buildings on the Project Site are or will be equipped with appropriate fire control measures including a water storage system and fire hoses. In addition, the following measures will be implemented:

• The mine rescue team at the Lalor Mine has been trained for emergency response, and is prepared to respond to any fire or explosion emergencies associated with the proposed Project.

• Upon completion of construction, Hudbay will prepare and implement an emergency response plan for the New Britannia Mill operations.

• In addition to Hudbay personnel, the Town of Snow Lake Fire Department will be alerted to respond in case of emergency.

• Storage and use of hazardous materials, including flammable waste, will be in compliance with regulatory requirements (as described in Section 6.11.2).

• Smoking will be restricted to designated areas.

With the measures outlined above and assuming implementation of typical safe work practices, the risk of fires and explosions is assessed to be appropriately mitigated.

6.11.4 Transportation Accidents

An increase in traffic has the potential to increase the likelihood for transportation accidents, including vehicular and wildlife collisions. Wildlife collisions are discussed above in Section 6.7.2.3.

Transportation accidents can result in the release of pollutants in the environment (diesel, oils, etc.) or materials that the vehicles are transporting (cement, etc.). Such accidental releases to the environment

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could potentially result in secondary effects on other environmental components (groundwater contamination through seepage, decline in surface water quality through runoff) or tertiary effects on vegetation (decline of growth potential due to soil contamination), wildlife, aquatic resources and human health.

Potential socio-economic effects may occur if road shutdowns are required in the event of a large accident (traffic interruptions could disrupt business and activity if people are not able to commute to work).

As discussed in Section 6.10.5, the increase in traffic on public and private roads (e.g. PR 395, PR 392, and PR 393) during construction is considered Minor. Hudbay will continue with the following measures to reduce the risk of transportation accidents:

• Vehicle speed limits will continue to be imposed (e.g. 20 km/hr at the New Britannia Mill site) on Hudbay and contractor vehicles.

• Contractors retained to drive and operate vehicles will abide by passing restrictions on the Snow Creek Bridge. If public vehicles are approaching the bridge at the same time as an ore truck, the ore truck will yield.

• Contractors retained to drive and operate vehicles will have a valid Manitoba Driver’s License with a copy provided to Hudbay.

• Speed limits on access roads, local roads and Provincial highways will continue to be implemented. Signage and speed limits on PR 395, PR 392, PTH 39 and PTH 10 are regulated by the Province of Manitoba.

• Hudbay will limit trucking hours during shift changes to avoid times at which there are heavy amounts of public traffic (i.e. employees traveling to or from Lalor Mine).

• As discussed in Section 2.7.8, the modular steel bridge will be available for use in emergencies if at any time the Snow Creek Bridge on PR 392 is inaccessible and ingress to or egress from the Town of Snow Lake is required.

The above-noted mitigation measures are assessed to mitigate the potential risk for transportation accidents occurring during all phases of the proposed alteration.

6.11.5 Power Failure

During construction and operation there is potential for environmental effects due to power failure. Site power may be lost due to power line failure, fire/explosion and/or severe weather. Leak detection for the Pipeline System will be provided by monitoring flow rates using meters located near each end of the pipe. Hudbay will provide backup power for all critical infrastructure and equipment including the leak detection system. The supply of backup power is anticipated to appropriately mitigate the potential risks of a power failure during construction and operation.

6.12 Summary of Environmental Effects and Mitigation Measures

The potential environmental effects of the construction and operation of the proposed alteration are considered Negligible, as described above in this chapter.

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Table 6-4 summarizes potential environmental effects of the proposed Project and the design features, standard operating procedures and other mitigation measures that will be implemented. Table 6-5 summarizes potential accidents and malfunctions and measures to reduce the risk of such occurrences.

*Additional mitigation measures are proposed in the Closure Plan (Section 7) and submitted to Manitoba Sustainable Development as a requirement under the project licencing process. Section 7 outlines detailed mitigation and monitoring requirements for reclamation of the Project Site.

Table 6-4: Summary of Environmental Assessment and Mitigation Measures

Environmental and SocialComponent Project Phase Sources of Potential Effects Mitigation Measures Residual Adverse Impact

PHYSICAL ENVIRONMENTTopography Construction Clearing, leveling, trenching for water

drainage, stockpiling materials during sitepreparation and construction of accessroads, and establishment of associatedlaydown areas.

Wherever practicable, existing access roads and laydown areas will be used in order to minimize changes to topography. Negligible

Segment 1 consists of previously disturbed areas and therefore minimal clearing and levelling will be required.

The closure phase will include restoration of any changes to topography of the site to match the pre-construction condition of the surroundingarea to the extent practical. The Closure Plan for the Project Site will be updated to include the closure activities associated with theproposed alteration.

Soil Erosion Construction Clearing, grubbing, excavating, levelling andvehicle traffic. High wind and precipitationevents also can lead to soil erosion, whichcan consequentially affect other componentsof the environment including air quality, waterquality, and vegetation.

Segment 1 and the new Truck Access Road consists of previously levelled and disturbed areas and therefore minimum clearing and levellingwill be required.

Negligible

Any activities that occur near culverts or other watercourses along the route will be carried out in accordance with applicable DFO’s“Measures to Avoid Causing Harm to Fish and Fish Habitat” or other applicable standards.Erosion and sediment control (ESC) measures will be in place to prevent the generation and movement of sediment-laden water.

Excavated materials will be stockpiled, compacted and reused where appropriate. Stockpile heights will be monitored and limited.

Excavation activities will not occur during high rain or wind events, to minimize the erosion potential of exposed soils.

At the time of closure, the Closure Plan for the Project will be strictly followed to ensure that required closure procedures associated with theproposed alteration are carried out.

Soil Compaction and Mixing ofSoil Horizons

Construction Incidental vehicle and heavy equipmentmovement, excavating, levelling, grading andstockpiling of materials.

Construction equipment and vehicle traffic will be limited to designated areas within and around work areas, including construction laydownareas at the Project Site.

Negligible

Construction activities will be limited during periods of severe precipitation and runoff.

Disturbed and exposed areas will be kept to a minimum with site restoration occurring as soon as is practical.

Disturbed areas will be re-vegetated following site closure.

Soil – Materials and WasteManagement

Construction Wastes such as used oils, rags, drums andmiscellaneous refuse can potentially affectsoil quality, which can in turn affect otherenvironmental components (e.g., vegetation,groundwater, and surface water).

Wastes generated during construction will be collected in garbage bins maintained at specific locations throughout the Project Site. The binswill be emptied on a regular basis for recycling and/or disposal at a licensed waste disposal facility.

Negligible

Waste oils and other hazardous materials generated (chemicals, reagents, waste oil, lubricants, or petroleum products) will be stored insecured containers equipped with spill containment. These materials will be removed by a licensed hazardous materials handler forappropriate disposal or recycling.

Groundwater Construction, Operation Fuel handling, lubricants and waste canpotentially affect groundwater quality due toleaks, spills and accidents. Thetransportation of tailings, copper concentrateand return water via the Pipeline System mayalso potentially affect groundwater quality inthe event of an accidental release.

There are no proposed underground works involved with this Project. Negligible

No withdrawals of groundwater are required for the proposed Project and in any case there is no concern about quantity of groundwaterbecause there are numerous pathways for groundwater recharge.The mitigation measures included in the project design (Section 2.7.1 and those identified in Section 6.11 (Accidents and Malfunctions) andSection 6.3.3 (Materials and Waste Management) are assessed to be adequate to prevent potential effects on groundwater.



Surface Water – WaterWithdrawal

Construction, Operation, andClosure

The withdrawal of water from waterbodies tosupply freshwater to the New Britannia Millhas the potential to adversely affect waterlevels in these waterbodies.

The majority of the water (approximately 90%) required for processing at New Britannia will be recycled water from Anderson TIA or processwater that is recycled within the mill itself. A minimal amount of freshwater from Snow Lake will be used for domestic purposes and reagentmixing.

Negligible

Surface Water Quality alongPipeline System

Construction Clearing, excavating All physical activities near Snow Creek will be carried out in accordance with DFO’s “Measures to Avoid Causing Harm to Fish and FishHabitat’’.

Negligible

Implementation of the measures to mitigate soil erosion (Section 6.3.1).

Operation Accidents, malfunctions Mitigation measures, as described in Section 2.7.1, have been built in to the Pipeline System design to prevent spills and leaks.

Additional mitigation measures are described in Section 6.11.2 (spills and leaks).

Surface Water – TailingsDeposition

Operation Tailings from New Britannia will have adifferent chemical composition than tailingsfrom Stall Concentrator which could affectwater quality in Anderson TIA andsubsequently discharge of effluent toAnderson Creek.

The cyanide destruction process to be applied in the New Britannia Mill (described in Section 2.5) will destroy most of the cyanide beforetailings leave the New Britannia Mill.

Negligible

Even before the effect of natural degradation in the Anderson TIA, none of the water quality parameters will exceed MDMER.

Degradation in the natural environment (by processes such as ultraviolet radiation (sunlight)) will further break down cyanide complexes andfurther decrease the residual cyanide concentrations.

Planned expansion of the Anderson TIA, which will be necessary to accommodate tailings discharged from the New Britannia Mill, will resultin an increase in surface area and retention time (with a complete cessation of discharge out of Anderson TIA for at least one year prior tooperation of the New Britannia Mill).

Continue weekly of the effluent discharged from Anderson TIA into Anderson Creek to ensure that it meets MDMER criteria (and therefore thelimits laid out under Environment Act Licence No. 3263).

If any exceedances occur, discharge will be shut off immediately and not resumed unless the water quality returns to acceptable limits.

Surface Water – WasteManagement

Construction, Operation Wastewater generated by the mill includesreturn water, grey water and sanitarysewage.

Design considerations provided in Section 2.7.1 provide mitigation measures for accidents related to the return water pipe. Negligible

Measures listed in Section 6.11.2 (spills and leaks) will be implemented to minimize risks of spills and leaks.

Wastewater generated during the operation of the mill will be managed using existing licensed treatment facilities. The existing facilities willcontinue to operate in accordance with the applicable Environment Act licenses/Clean Environment Commission Orders.

During operation, return water from the mill (Section 2.7.3) will be deposited into the Anderson TIA. This water will not contain tailings;therefore, it will not affect the surface water quality of the Anderson TIA.

Dust – Pipeline System Construction, Operation,Closure

Clearing, grubbing, levelling, stripping oftopsoil, stockpiling materials, blasting,movement of constructionequipment/vehicles and/or employees, andgeneral use of equipment.

Unloading ore from trucks and stockpiling,scrubbers on the crusher, lime silo stack,conveyors and movement of vehicles.

Dust suppression activities, such as the use of approved dust control agents will be undertaken on unpaved roads including the new PipelineSystem access road.

Negligible

The increase in traffic during construction and closure phases is temporary.

At all times, vehicles will be required to adhere to Hudbay’s speed limits on main roads and access roads.

The same speed limit (or less) will apply to the Pipeline System access road and will be similar to other speed limits on Hudbay access roadsof 40 km /hr (or less). The New Britannia Mill site has a speed limit of 20 km/hr, which will continue to be imposed.

Vegetated buffers will be maintained to minimize the transport of dust generated on the Project Site.



Dust – New Britannia Mill(Excluding Truck Access Road)

Construction, Closure Clearing, levelling, stockpiling materials,blasting, movement of constructionequipment/vehicles and/or employees, andgeneral use of equipment.

Areas to be cleared will be minimized where feasible. Negligible

Project components will be situated primarily on previously disturbed areas.Stockpiled materials will be compacted and re-used, where practicable.

Material stockpile heights will be limited.

Trucks hauling materials will be covered to minimize dust coming off loads.

Re-vegetation of disturbed areas will occur as part of site closure activities and will provide long term mitigation of dust effects uponcompletion of closure activities.

Operation Unloading ore from trucks and stockpiling,scrubbers on the crusher, lime silo stack,conveyors and movement of vehicles.

Crusher will be enclosed and equipped with a wet scrubber. Negligible

Most conveyors will be enclosed.

The lime silo will be equipped with a dust collection system which will be used during lime offloading.

Dust – Truck Access Road Construction, Closure Clearing, grubbing, levelling, stripping oftopsoil, stockpiling materials, blasting,movement of constructionequipment/vehicles and/or employees, andgeneral use of equipment.

Areas to be cleared will be minimized where feasible. Negligible

The development of the Truck Access Road will occur primarily on previously disturbed areas.

Stockpiled materials will be compacted and re-used, where practicable.

Material stockpile heights will be limited.

Trucks hauling materials will be covered to minimize dust coming off loads.

Re-vegetation of disturbed areas will occur as part of site closure activities and will provide long term mitigation of dust effects uponcompletion of closure activities.

Operation Truck movement along the Truck AccessRoad.

Dust suppression activities, such as the use of approved dust control agents will be undertaken on unpaved roads including the new PipelineSystem access road.

Minor

At all times, vehicles will be required to adhere to Hudbay’s speed limits on main roads and access roads.

The same speed limit (or less) will apply to the Pipeline System access road and will be similar to other speed limits on Hudbay access roadsof 40 km /hr (or less). The New Britannia Mill site has a speed limit of 20 km/hr, which will continue to be imposed.

Vegetated buffers will be maintained to minimize the transport of dust generated on the New Britannia Mill site and Truck Access Road.

ATMOSPHERIC ENVIRONMENTAir Emissions (excluding dust) Construction, Operation,

ClosureVehicles and exhausts from dieselconstruction equipment (general vehiclemovement on site, using equipment forgrading, placing materials etc.).

Vehicles and equipment will be well maintained. Negligible

Vehicle idling will be kept to a minimum.

All vehicles used for the Project will comply with Environment Canada’s On-Road Vehicle and Engine Emission Regulations as required.

Noise and Vibration Construction Sources of noise associated with the Projectconstruction include the installation of a newflotation building and pipeline infrastructurefor transporting tailings.

Standard backup alarms will be replaced with broadband alarms for mobile equipment at the New Britannia Mill site and in the area adjacentto the residence near the cemetery (for construction of the Pipeline System).

Negligible

Adjust construction activities by modifying equipment usage (e.g., duration or quantity).

Advise nearby residents of major noise-generating activities, and determine if additional mitigation is required.

Maintain machinery and noise-abatement equipment.

Establish a procedure or protocol that addresses concerns in a timely manner.



Operation During operation, examples of primarysources of noise include ore crushers,conveyors, delivery trucks, other mobileequipment and supporting HVAC equipmentat the New Britannia Mill site.

Floatation and mill building façade construction meeting a minimum sound transmission loss (STC) of 30. Negligible

Delivery of ore materials and other vehicle traffic limited to daytime hours (7:00-22:00).

Alternative back-up alarms for vehicles.

Vehicles and equipment will be well maintained.

Hudbay provides hearing protection as required to ensure employees working on site are protected from noise during construction, operationand closure activities.

Construction of a sound barrier between the mill and the Snow Lake (Lalor) Camp (as described above in Section 2.6).

Closure Sources of noise associated with closureactivities include noise generated byremoving buildings and pipelineinfrastructure.

All closure activities will be carried out in accordance with The Workplace Safety and Health Act and the Hudbay Occupational Health andSafety Standard (OHSAS) 18000 certified management system

Negligible

Climate Construction, Operation,Closure

Vehicle exhausts and exhausts from dieselconstruction equipment (e.g. general vehiclemovement on site, using equipment forgrading and placing materials).

Mitigation measures listed in Section 6.6.2 (air emissions) will be implemented. Negligible

The filtration system for copper concentrate at New Britannia will decrease moisture content in copper concentrate shipped from NorthernManitoba to Canadian or other markets, thereby decreasing the amount of fuel used for transportation by truck and rail.

TERRESTRIAL ENVIRONMENTVegetation - Clearing Construction Clearing will be required along the Pipeline

System of a total approximate maximum areaof 11.36 ha.

The cover classes are common to the area in and surrounding the Project Region. Therefore, the removal of this vegetation will not result in asubstantial loss of the overall cover types.

Minor

Traditional knowledge holders observed medicinal plants in wetland areas during field studies (discussed above in Section 4.6.3). Thesewetlands, which are located adjacent to the New Britannia Mill site, will be avoided to the extent feasible.Upon closure, the Project Site will be returned to native conditions to the maximum extent feasible. Once the infrastructure on the site hasbeen removed and the site has been re-graded, disturbed areas will be re-vegetated with native vegetation species in accordance with theClosure Plan. The success of re-vegetation efforts at the Project Site will be regularly monitored with subsequent re-vegetation occurring asrequired. Monitoring of re-vegetation efforts will occur on an annual basis until determined by regulators to be successful.

Vegetation – Dust Deposition Construction, Operation, andClosure

Sources of dust include: clearing, grubbing,levelling, stripping of topsoil, stockpilingmaterials, blasting, movement of constructionequipment/vehicles and/or employees, andgeneral use of equipment, unloading orefrom trucks and stockpiling, scrubbers on thecrusher, lime silo stack, conveyors andmovement of vehicles, traffic.

Implementation of the mitigation measures in Section 6.6.1 (Dust). Negligible

Protected Vegetation Species Construction, Operation Changes in habitat quality and quantity. Thepathway of effect is primarily through indirecteffects on other environmental components(such as clearing or dust deposition).

The mitigation measures applied to other components will sufficiently mitigate the potential effect on protected species (Sections 6.7.1.1(clearing) and 6.6.1 (dust)).

Negligible

No Flooded Jellyskin were observed in the terrestrial surveys undertaken as part of the baseline investigations nor have they been observedin the Project Area during previous environmental surveys conducted by AECOM in the Snow Lake region. It is assessed that FloodedJellyskin are not likely present within the Project Site.

Wildlife – Loss of Habitat Construction Loss of vegetation through clearing canaffect wildlife by reducing the amount ofhabitat available

As described in Section 6.7.1.1 (clearing), the cover classes affected by the construction of the Pipeline System are not unique to the ProjectArea. There is an abundance of similar habitat types throughout the Project Region.

Negligible

Traditional knowledge holders indicated that the route of the Pipeline System is not a preferred hunting or trapping area.



Nesting birds that may use edge habitat available along the route of the Pipeline System will be able to continue to use this habitat followingthe development of the Project.

No clearing will occur in the peak migratory bird nesting season, approximately May 12 to August 5.

No clearing will occur in the shoulder nesting season (approximately from April 28-May 11 and August 6-20) unless a nest search isconducted by a biologist no more than three days prior to clearing. If a nest is found, an appropriate ‘no activity’ buffer is established (e.g. 60m) until the nest is no longer active and the young have left the nesting area.

Clearing will be minimized to the extent feasible.

In accordance with the approved Closure Plan, upon closure the Project Site will be re-vegetated, restoring native conditions to the extentfeasible.

Wildlife - Noise Construction, Operation,Closure

Noise generated during construction,operation and closure phases of theproposed Project has the potential to disturbwildlife within the Project Area. Duringconstruction, noise will be generated tovarying degrees.

It is anticipated that local wildlife are likely already accustomed to some level of noise based on the existing activity in the area (e.g. SnowLake Camp, PR 395, PR 392 and the Stall Concentrator).

Negligible

If local wildlife are deterred from the Project Site, it is not anticipated that this will substantially affect wildlife as similar habitats are available inthe Project Area and Project Region.

The duration of the effect is short-term, considering construction of the Pipeline System will occur during one year.

Wildlife – Risk of VehicleCollisions

Construction, Operation,Closure

Anticipated increase in traffic on local publicroads

As local wildlife populations are considered low, the potential for increased wildlife collisions is also considered low. Negligible

Hudbay’s experience in the local area indicates that wildlife collisions are rare. Any collision with a Hudbay or contractor vehicle would have tobe reported in Hudbay’s system. The records contained in the system have been reviewed back to 2012, and the system contains no suchreports.Speed limits on access roads, local roads and Provincial highways will continue to be implemented.

Wildlife – Protected Species Construction, Operation,Closure

Changes in habitat quality and quantity. Thepathway of effect is primarily through indirecteffects on other environmental components(e.g. vegetation clearing, disturbance due toProject construction activities).

The Project Site is a largely previously disturbed area (e.g. mining operations, Manitoba Hydro transmission line corridor) and provides verylimited ideal habitat for protected wildlife species.

Negligible

Mitigation measures identified in Section 6.7.1.1 (clearing) and Section 6.7.2.1 (loss of habitat) will be applied for protected wildlife species.

AQUATIC RESOURCESFish and Fish Habitat Construction, Operation,

ClosureEffects on aquatic resources occur primarilythrough changes in habitat quality orquantity. Habitat quality may be affected bychanges in surface water quality, surfacerunoff (elevated concentration of metals orother contaminants), air dispersion (dust) orany accidental leaks or spills during theconstruction phase of the Project. Habitatquantity can be reduced through directchanges in habitat caused by constructionactivities. The only waterbody within theProject Site is Snow Creek. Some riparianvegetation will be cleared to construct thePipeline System which may result in a

Snow Creek does not appear to support sensitive or unique fish habitat at the proposed water crossing. Negligible

Clearing of riparian vegetation will be minimized to the extent feasible.Riparian vegetation (coniferous mixed-wood forest, as described above in Section 4.8.2.7) is common throughout the assessed length ofSnow Creek and the amount to be cleared (approximately 20 m by 20 m) is small given the length of the Creek (approximately 6 km).Any activities that occur near Snow Creek will be carried out in accordance with applicable DFO “Measures to Avoid Causing Harm to Fishand Fish Habitat” or other applicable standards.

No fish Species at Risk were observed during aquatic surveys.No component of the Pipeline System (i.e. the modular steel bridge) will be constructed below the high water mark. The bridge will be a clear-span structure, support on abutments placed above the high-water mark. No instream works are anticipated to be required.Mitigation measures built in to the Pipeline System design (Section 2.7.1) will mitigate the risks of any spills or leaks which could have aneffect on fish and fish habitat.

Water quality downstream of Anderson TIA will not be affected by the Project, therefore fish habitat downstream of Anderson TIA will not beaffected. There are no physical activities that could affect fish and fish habitat downstream of Anderson TIA.



potential loss of habitat at the proposedwater crossing.

The mitigation measures outlined above and identified in Section 6.3 (soil), Section 6.6 (air), and Section 6.11 (accidents and malfunctions)are sufficient to prevent potential effects on fish and fish habitat.

Lower Trophic Level Biota Construction, Operation,Closure

Lower trophic level biota can be affected by achange in surface water quality and habitatdisruption. There is a potential for surfacerunoff and potential spills to adversely affectsurface water quality along the route of thePipeline System.

Mitigation measures are in Section 6.3.1 (soil erosion), Section 6.5(surface water), and Section 6.11.2 (spills and leaks). Negligible

Protected Aquatic Species Construction, Operation,Closure

Protected aquatic species can be impactedby project activities and components throughchanges in habitat quality and quantity. Thepathway of effect would be primarily throughindirect effects on other environmentalcomponents (e.g. erosion, surface waterquality).

It is assessed that the mitigation measures applied to other components are sufficient to prevent the potential effect on protected species (e.g.Sections 6.3.1 (erosion), and 6.5.2 (surface water quality)).

Negligible

It is unlikely that protected species occur in any area which could be potentially affected by the Project. As noted in Section 4.7, no aquaticspecies were identified to potentially be within the Project Region.

SOCIOECONOMIC ENVIRONMENTLand and Resource Use Construction, Operation and

ClosureLand and resource uses and users in theProject Region that may be indirectlyimpacted include:

· Harvesting and trappingopportunities.

· Fishing (recreational, subsistenceand commercial).

· Recreational use of existing trails.· General use of the Project Area

and Region.

The New Britannia Mill site and the end of the Pipeline System, the Stall Concentrator/Anderson TIA are fully-developed and have been usedfor mining purposes for decades.

Negligible

As described in Section 1.6, the area in between the New Britannia Mill site and the Stall Concentrator, to be occupied by the PipelineSystem, lies within the area subject to Town of Snow Lake By-law which, for reasons of human safety, prohibits hunting to all exceptregistered trapline owners.No activity, component or impact of the proposed alteration will impede access to downstream resources or affect any current user’s ability tocontinue to exercise any recreational, commercial or subsistence use of these resources.All trappers with rights in the area to be affected have been identified and Hudbay maintains communication with them and works with them toensure that access to their traplines is not impacted as a result of Hudbay projects.With respect to snowmobile trails, Hudbay has discussed the proposed alteration with members of the Sno-Drifters snowmobiling club. Theclub has raised concerns related to access to their trails. Similar to other Hudbay Projects, Hudbay will provide allow access across thePipeline System in areas of their trails.As described in Section 6.8, there will be no impact to Fish or Fish Habitat and therefore no impact on fishing activities.Since residual impact on wildlife is assessed to be Negligible (Section 6.7.2.5), there will be no impacts on hunting in the Project Region.

Heritage Resources Construction Clearing and excavating As described in Section 4.7.2, there are no recorded heritage resources at the Project Site and the potential for any to be found is minimal. Negligible

If artifacts or historical features of skeletal remains are encountered during construction activities, work activities will stop immediately aroundthe affected area with the find reported to the site supervisor. A qualified archaeologist would investigate and assess the find prior tocontinuation of work.If skeletal remains are encountered, the find will be immediately reported to the site supervisor and the RCMP.

Aesthetics Construction, Operation General project activities Project components are located in areas that have been previously disturbed as part of the New Britannia Mill, Snow Lake Camp, StallConcentrator, Anderson TIA, historic mining activities, and adjacent to the Manitoba Hydro ROW.

Negligible

The Project Site will be inspected on a regular basis for loose waste and debris in order to maintain a clean site.

Waste and debris will be stored in bins and removed from the site on a regular basis.

The Closure Plan for the New Britannia Mill will be updated to include the closure activities associated with the proposed Project. During theclosure phase, the Project Site will be re-vegetated and returned to native conditions to the extent feasible.



Effects on Indigenous Peoples Construction, Operation,Closure

Similar to land and resource use, traditionalresource use could be affected by generalproject activities.

The Project Site is not located near any First Nations communities or heritage location. Based on Government of Manitoba and Federalsources, there is no Indian Reserve or Registered Trap Line zone within the Project Region.

Not applicable

No First Nation or Aboriginal resource (hunting, fishing, trapping) or traditional use that could be affected by the proposed Project wasidentified during the engagement process or in other public and stakeholder meetings (described above in Section 5).As described in Section 1.6, the area in between the New Britannia Mill site and the Stall Concentrator, to be occupied by the PipelineSystem, lies within the area subject to Town of Snow Lake By-law which, for reasons of human safety, prohibits hunting to all exceptregistered trapline owners (none of whom is associated with an Indigenous community). Restrictions with respect to human safety generallyapply to all users.With respect to the surrounding Project Region, as assessed in Section 6.10.1, resources which could be used for fishing and hunting will notbe affected by the proposed Project.While harvesting of medicinal plants cannot be absolutely ruled out, no such use was identified in the engagement process and habitatconditions where potentially medicinal plants were observed are relatively common in the Project Region.Further, during construction, Hudbay will apply the following mitigation measures:

· These areas will be avoided to the extent feasible.· Hudbay will include in the construction team a traditional knowledge holder who can advise on areas to be avoided.· Clearing will be carried out under winter conditions when plants are not being harvested.

Traffic Construction, Operation, andClosure

During the construction and closure phases,traffic will increase by approximately fivevehicles per day.

During the operation phase, traffic willincrease as described in Table 6-3. Truckswill haul ore from Lalor Mine to New Britanniavia PR 395 and then PR 392. Trucks willalso transport copper concentrate from NewBritannia to Flin Flon for further processingvia PR 392 (south of PR 393).

The results of the traffic study in Appendix C show that no additional mitigation measures are required to accommodate the increase in trucktraffic as a result of the operation. Highway conditions was the most commonly expressed public concern noted during the Public InformationSessions that were held in Snow Lake in May 2018 and December 2018. Hudbay has relayed the concerns expressed by Snow Lakeresidents to Manitoba Infrastructure.

Minor

The effect of traffic on the Town of Snow Lake is assessed to be Minor when taking into account mitigation measures described inSection 6.6.1 (dust) and Section 6.11.4 (transportation accidents).


Table 6-5: Summary of Potential Accidents and Malfunctions and Measures to Mitigate Risk of Occurrence

Risks Associated with Accidentsand Malfunctions Project Phase Possible Consequences Measures to Reduce Risk of Occurrence Conclusion

Worker Health and Safety Construction, Operation andClosure

Risk of workplace accidents affecting workerhealth

Worker protection in Manitoba is regulated through standards, procedures and training required under The Workplace Safety and Health Act.In addition, all Hudbay operations abide by their internal health and safety requirements as covered under its certified safety managementsystem, OHSAS 18001.

Risk is assessed to beappropriately mitigated

Safety training, equipment and personal protective equipment are supplied to employees.

Safety equipment, including cyanide antidote kits, will be located throughout the New Britannia Mill and accessible to all employees. Specialtraining in relation to cyanide handling will be administered.

Spills and Leaks Construction, Operation andClosure

Spills and leaks from diesel fuel, lubricants,oils, hydraulic fluids, and other hazardousmaterials can have adverse effects to air,surface water, groundwater and soils, withconsequential effects on vegetation, aquaticresources and possible human health andsafety.

Mitigation measures that have been built in to the design of the Pipeline System are as follows (described above in Section 2.7.1):· All or most segments of the pipes will be thermal welded in order to eliminate opportunities for leaks to occur.

o The use of flanged or clamped sections will be minimized.· Leak detection along the length of the pipes will be provided by monitoring flow rates using meters located near each end of the

pipe.o A rupture in the pipe would result in a difference between the two flow rates, which will be picked up through the mill control

system.· Communication to the New Britannia Mill process control system will be provided by fibre optic cable running the length of the

Pipeline System. In the event of an alarm, site personnel will be dispatched to visually inspect the length of the pipeline to determineif there is a problem.

· The pipes will be double-walled as they cross Snow Creek and for approximately 500 m on either side of Snow Creek.· The pipes will be covered with a sand berm to a depth of approximately 500 mm to minimize seasonal pipe expansion and

contraction and to prevent the pipe from being breached in case of an accidental impact.· Recycled water will be pumped through the pipe to prevent freezing during prolonged process outages.· The pipes will be visually inspected daily by dedicated personnel.

In addition to the above mitigation measures, the Tailings Pipe and the Copper Concentrate Pipe will be equipped with the following:· Variable frequency drives will be installed on each pump to maintain a minimum flow velocity to prevent particle settling and

plugging.· The variable frequency drives will also be interlocked so that, in the unlikely event of a pressure change, the pumps will stop,

providing an opportunity for dedicated personnel to check the cause of the pressure change and take action in case of a leak.

Risk is assessed to beappropriately mitigated

Storage of chemicals and reagents used in the New Britannia Mill will follow the requirements outlined in Section 2.9.4.

Any diesel tanks used on site will be self-contained aboveground storage tank(s).

When servicing requires drainage or pumping of lubricating oils or other fuels from equipment, a groundsheet of suitable material and size willbe spread on the ground to catch all fluid in the event of a leak or spill. An adequate supply of suitable absorbent material and any othersupplies and equipment necessary to immediately clean up spills will also be available.Storage and disposal of liquid wastes and filters from equipment maintenance, and residual material from spill clean-up will be contained in anenvironmentally safe manner and in accordance with existing regulations.Waste oils, fuels, and other hazardous wastes will be handled in a safe manner. Staff will be required to transport, store, and handle all suchsubstances as recommended by the suppliers and/or manufacturers and in compliance with applicable federal, provincial, and municipalregulations. Manitoba Sustainable Development will be notified immediately if a reportable spill occurs.Fuels, oils, or other hazardous materials will be stored only in designated areas.

Hudbay will ensure that fuel handlers are trained and qualified and that appropriate emergency response measures are in place and readilyavailable.

Storage sites will be inspected periodically for compliance with requirements as applicable.

Personnel on-site will be trained in how to deal with spills, including knowledge of how to properly deploy site spill kit materials.

Service and repairs of equipment will only be performed by trained personnel.


Risks Associated with Accidentsand Malfunctions Project Phase Possible Consequences Measures to Reduce Risk of Occurrence Conclusion

Vehicles and equipment will be maintained to minimize leaks. Regular inspections of hydraulic fuel systems on machinery will be completedon a routine basis; when detected, leaks will be repaired immediately.

Fires and Explosions Construction, Operation andClosure

Accidental fires and explosions frommechanical equipment, fuels, and otherhazardous materials may result in loss ofequipment and infrastructure, worker healthand safety risk, and deterioration or loss ofnatural habitat. Potential socio-economiceffects may occur if a site shut-down isrequired in the event of a large accident

The Project Site is already equipped with appropriate fire control measures including a water storage system and fire hoses. Risk is assessed to beappropriately mitigatedThe mine rescue team at the Lalor Mine has been trained for emergency response, and is prepared to respond to any fire or explosion

emergencies associated with the proposed Project.In addition to Hudbay personnel, the Town of Snow Lake Fire Department will be alerted to respond in case of emergency.

Storage and use of hazardous materials, including flammable waste, will be in compliance with regulatory requirements (as described inSection 6.11.2).

Smoking will be restricted to designated areas.Transportation Accidents Construction, Operation and

ClosureVehicular collisions (human health and safety,traffic disruption, road closure, release ofcontaminants) and wildlife collisions (loss ofwildlife, human health and safety, roadclosures).

Vehicle speed limits will continue to be imposed (e.g. 20 km/hr at the New Britannia Mill site). Risk is assessed to beappropriately mitigatedContractors retained to drive and operate vehicles will abide by passing restrictions on the Snow Creek Bridge. If public vehicles are

approaching the bridge at the same time as an ore truck, the ore truck will yield.Contractors retained to drive and operate vehicles will have a valid Manitoba Driver’s License with a copy provided to Hudbay.

Speed limits on access roads, local roads and Provincial highways will continue to be implemented. Signage and speed limits on PR 395, PR392, PTH 39 and PTH 10 are regulated by the Province of Manitoba.Hudbay will limit trucking hours during shift changes to avoid heavy amounts of public traffic (i.e. employees traveling to or from Lalor Mine).

As discussed in Section 2.7.8, the modular steel bridge will be available for use in emergencies if at any time the Snow Creek Bridge on PR392 is inaccessible and ingress to or egress from the Town of Snow Lake is required.

Power Failure Construction, Operation andClosure

Loss of power potentially leading to equipmentmalfunctions and accidents, and environmentaleffects.

Hudbay will provide backup power for all critical infrastructure and equipment including the leak detection system. Risk is assessed to beappropriately mitigated

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7. Monitoring and Follow-up

Follow-up programs verify the accuracy of the environmental assessment of a project and determine the effectiveness of measures taken to mitigate the adverse environmental effects of the project. Monitoring programs currently required in relation to the New Britannia Mill and Anderson TIA will continue to be appropriate, given the impacts assessed in relation to the proposed Project.

7.1 Construction Monitoring

As discussed in Section 6.10.4 above, a traditional knowledge holder will be included in the construction team to provide advice on areas that should be avoided. A member of the Hudbay environment staff also will be included in the construction team to monitor activities for compliance with this assessment and terms of the Environment Act licence.

7.2 Continued Monitoring Associated with the Operation of New Britannia Mill

7.2.1 MDMER

During the operation of the New Britannia Mill, Environmental Effects Monitoring (EEM) conducted under the MDMER for the Chisel North WTP and the Anderson TIA will continue. Monitoring will include examining the potential effects of effluent on fish population, fish tissue and on benthic invertebrate communities in local waterbodies potentially influenced by the New Britannia Mill support facilities. Studies have been conducted in accordance with EEM in 2004, 2007, 2009, 2011, 2014 and 2018 for the Anderson TIA. These monitoring activities are anticipated to continue through operation of the New Britannia Mill and following closure until it can be demonstrated that no adverse effects are occurring. Hudbay will continue to collect water samples at the Anderson TIA discharge point once per week while water discharges from the Anderson TIA in accordance with the MDMER.

7.2.2 Environment Act Licences

Monitoring programs also are required under existing Environment Act Licence No. 3263 for Anderson TIA and the Environment Act License No. 1878 RR for the New Britannia Mill.

7.2.3 Success of Re-vegetation Efforts

It continues to be anticipated that the end-use of the New Britannia Mill site and along the Pipeline System will consist of a natural space with no planned residential, commercial, or industrial development. Based on Hudbay’s mine closure experience in the Snow Lake region, the growth of grasses and mosses is apparent within the first few years following closure, whereas trees and shrubs take longer to establish. Vegetation in areas temporarily disturbed by construction activities is expected to naturally encroach and establish. If, during periodic inspections of the project components, these areas have not successfully been re-vegetated, artificial re-vegetation efforts may occur to encourage re-vegetation. To ensure the success of the re-vegetation program, a re-vegetation monitoring program will be implemented. The

Hudbay Minerals Inc



monitoring program will determine the success of the re-vegetation program and determine if follow-up reseeding or replanting is required. The monitoring program will include quarterly monitoring during the growing season until the seedlings appear to be established, following which, quarterly monitoring will continue for a minimum of two years, before a successful re-vegetation program can be declared.

7.2.4 Dust Monitoring and Air Dispersion Modelling

Due to the results of the air dispersion modelling, dust monitoring will be implemented during the operation of New Britannia Mill. This monitoring program will provide up to date, data for the air dispersion model and will allow Hudbay to determine if additional mitigation measures are required.

7.2.5 New Britannia Mill Closure Plan Update

Once the proposed Project has been constructed, Hudbay will file for the approval of the Director of Mines a revised Closure Plan and associated financial assurance in accordance with Sections 74 and 191 of the Mines and Minerals Act.

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8. Conclusion

Overall the adverse residual effects of the proposed alteration to the New Britannia Mill are considered to be Negligible to Minor in magnitude and mitigable with the measures incorporated into the Project design and recommended herein. The results of the effects assessment can be summarized as follows: Topography Construction and operation of the New Britannia Mill and Pipeline System will not affect the local topography. The New Britannia Mill site and the end of the Pipeline System in the Stall Concentrator/Anderson TIA site are both sites which are currently occupied by mining operations; and the route of the Pipeline System will run approximately parallel to an existing Manitoba Hydro ROW. Wherever practicable, existing access roads and laydown areas will be used in order to minimize changes to topography. The closure phase will include restoration of any changes to topography of the site to match the pre-construction condition of the surrounding area to the extent practical. Soil None of the proposed construction or operation activities are expected to entail new impact to soil. Disturbed and exposed areas will be kept to a minimum with site restoration occurring as soon as is practical. Wastes generated during construction, including hazardous materials, will be collected in bins maintained at specific locations throughout the Project Site. The bins will be emptied on a regular basis for recycling and/or disposal at a licensed waste disposal facility. All disturbed areas will be re-vegetated following site closure. Groundwater Construction and operation of the New Britannia Mill and Pipeline System will not affect the local groundwater. There are no underground works involved with this Project, and no withdrawals of groundwater are required. No effects from waste management or accidents and spills are expected. Surface Water

The existing facilities will continue to operate in accordance with the applicable Environment Act licenses. AECOM completed a water quality assessment to determine the effect on water quality of adding tailings from New Britannia Mill into Anderson TIA. This water quality assessment concluded that effluent discharge from the Anderson TIA will continue to meet regulatory criteria, and it is expected that effluent from Anderson TIA that flows into Anderson Creek and further downstream into Anderson Bay of Wekusko Lake will also continue to meet the required water quality guidelines. No additional water treatment will be required at the Anderson TIA final discharge point. Wastewater generated by New Britannia Mill, including return water, grey water and sanitary sewage, will be stored in tanks and will be managed using existing licensed treatment facilities.

Hudbay Minerals Inc



To prevent potential effects on surface water quality during construction, all physical activities near natural waterbodies will be carried out in accordance with DFO’s “Measures to Avoid Causing Harm to Fish and Fish Habitat,” and the Pipeline System has been designed to prevent spills and leaks. No impact to surface water quantity is expected during construction and operation. The majority of the water required for processing at New Britannia Mill will be recycled water from Anderson TIA or process water that is recycled within the mill itself. Only a minimal amount of freshwater from Snow Lake will be used for domestic purposes and reagent mixing.

Dust

The effect of dust during construction and operation will be Negligible to Minor. Areas to be cleared will be minimized and vegetative buffers, where present, will be maintained to mitigate wind effects and overall potential dust migration. The crusher will be enclosed and equipped with a wet scrubber. All conveyors are either inside a building or enclosed in a gallery which contains dust. Trucks hauling materials will be covered to minimize dust coming off loads. Dust suppression activities, such as the use of approved dust control agents will be undertaken on unpaved roads including the upgraded Truck Access Road and the new Pipeline System access road and at all times, vehicles will be required to adhere to Hudbay’s sped limits on main roads and access roads.

Air Emissions (Excluding Dust)

Air quality will not be adversely affected by emissions from equipment and vehicles. All vehicles used for the Project will comply with Environment Canada’s On-Road Vehicle and Engine Emission Regulations as required, vehicles and equipment will be well maintained, and idling will be kept to a minimum.

Noise and Vibration

At the New Britannia Mill site, noise generating activity will occur during construction and operation. On the Pipeline System portion of the Project, noise generating activity will occur largely only during construction. Acoustic assessments carried out by AECOM concluded that the effect of noise during the construction and operation phases of the Project will be negligible following the implementation of proposed mitigation measures, including improved soundproofing on site buildings, installation of a sound barrier, modifications to backup alarms, equipment maintenance and operational controls.

All activities performed by Hudbay will be carried out in accordance with The Workplace Safety and Health Act and the Hudbay OHSAS 18000 certified management system, which will avoid potential effects on health and safety.

Protected and Other Vegetation Although construction of the Pipeline System will result in a loss of vegetation, clearing will be kept to the minimum extent possible. No unique vegetation communities will be lost, and the species lost to clearing are common in the region. Although medicinal plants were observed in wetland areas during field studies, these wetlands (which are located adjacent to the New Britannia Mill site) will be avoided to the extent feasible during construction.

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At closure, the Project Site will be returned to native conditions to the maximum extent feasible. Once the infrastructure on the site has been removed and the site has been re-graded, disturbed areas will be re-vegetated with native vegetation species in accordance with the Closure Plan.

Protected and Other Wildlife

The potential impact of loss of habitat on wildlife species will be Negligible. The cover classes affected by the construction of the Pipeline System are not unique to the Project Area, and there is an abundance of similar habitat types throughout the region.

Nesting birds that may use edge habitat available along the route of the Pipeline System will be able to continue to use this habitat following the development of the Project. No clearing will occur in the peak migratory bird nesting season, and no clearing will occur in the shoulder nesting season unless a nest search is conducted by a biologist prior to clearing.

It is anticipated that local wildlife are likely already accustomed to some level of noise based on the existing mining activity in the area, and there is very limited ideal habitat for protected wildlife species in the Project Region. If local wildlife are deterred from the Project Site, it is not anticipated that this will substantially affect wildlife as similar habitats are available in the Project Region. The potential risk of vehicle collisions with wildlife is considered low, and speed limits on access roads, local roads and Provincial highways will reduce the risk of wildlife collisions.

Aquatic Resources

There is no fish or fish habitat at the New Britannia Mill site or at the end of the Pipeline System (the site of the Stall Concentrator). The only waterbody within the Project Site is Snow Creek. The Pipeline System will cross Snow Creek via a modular steel bridge. No component of the Pipeline System, including the modular steel bridge, will be constructed below the high water mark. The bridge will be a clear-span structure, supported on abutments placed above the high-water mark. No instream works are anticipated to be required. Mitigation measures built into the design of the Pipeline System will appropriately mitigate the risks of any spills or leaks which could have an effect on fish and fish habitat. Any activities that occur near Snow Creek will be carried out in accordance with applicable DFO “Measures to Avoid Causing Harm to Fish and Fish Habitat” or other applicable standards. Some riparian vegetation will be cleared to construct the Pipeline System which may result in a potential loss of habitat at the proposed water crossing. However, clearing of riparian vegetation will be minimized to the extent feasible and the riparian vegetation that will be removed is common throughout the assessed length of Snow Creek. Based on desktop review, it is unlikely that protected fish species occur in any area which could be potentially affected by the Project. No protected fish species were identified within the Project Region during field studies. The proposed Project does not require undertaking any activities in or near Snow Lake; therefore, there will be no effect on fish or fish habitat in Snow Lake.

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Climate

Although climate change effects due to greenhouse gas emissions are considered irreversible, the overall quantity of greenhouse gas emissions generated during construction and operation of the New Britannia Mill is considered to have a Negligible effect on climate change.

Land Use

As residual environmental effects on terrestrial and aquatic resources have been determined to be Minor to Negligible in magnitude, it is anticipated that the Project will not adversely impact the availability of plants, wildlife and fish for resource harvesting in the region. As a result, no change in land use is anticipated.

Hudbay has had discussions with all of the registered trapline owners in the Project Area, and none have expressed any concerns with respect to the proposed Project. Hudbay maintains communication with these trappers.

Heritage Resources

There are no recorded heritage resources at the Project Site and the potential for any to be found is minimal. There will be no further disturbance beyond the Project Site during construction and operation.

Aesthetics

Project components are located in areas that have been previously disturbed as part of mining and transmission line projects and therefore no adverse change in the existing aesthetics is expected. The Project Site will be inspected on a regular basis for loose waste and debris in order to maintain a clean site, and waste and debris will be stored in bins and removed from the site on a regular basis.

Indigenous Peoples

The Project Site is not located near any First Nations communities or heritage location, and the Project does not appear to require occupation of lands known to be currently used for traditional purposes by Indigenous peoples. The New Britannia Mill site is a wholly developed operational site, which has been an active mining operation since 1948. Similarly, the end of the Pipeline System is within an active area that is occupied by Hudbay’s Stall Concentrator. The area in between the New Britannia Mill site and the Stall Concentrator, to be occupied by the Pipeline System, lies within the area subject to Town of Snow Lake By-law which, for reasons of human safety, prohibits hunting to all except registered trapline owners (none of whom is associated with an Indigenous community). Restrictions with respect to human safety generally apply to all users. No First Nation or Aboriginal resource (hunting, fishing, trapping) or traditional use that could be affected by the proposed Project was identified during the engagement process or in other public and stakeholder meetings. While harvesting of medicinal plants cannot be absolutely ruled out, no such use was identified in the engagement process and habitat conditions where potentially medicinal plants were observed are relatively common in the Project Region.

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Traffic

Although vehicular traffic will increase slightly during construction and operation of the New Britannia Mill, the effect of traffic on the Town of Snow Lake is assessed to be minor. A traffic study completed by AECOM shows that no additional mitigation measures are required to accommodate the increase in truck traffic.

Conclusion

It is recommended that mitigation measures and monitoring programs described in this report be implemented to ensure potential environmental effects are minimized and/or identified early so that appropriate action can be undertaken. Monitoring programs that have been recommended include construction monitoring, continued Environmental Effects Monitoring (EEM) and monitoring requirements under the existing Environment Act licenses, and the success of re-vegetation efforts at site closure. In summary, the residual environmental effects will be Negligible to Minor in magnitude with the implementation of mitigation measures identified and monitoring programs proposed. It is our opinion that based on the available information and documented assumptions the proposed Project is not likely to cause significant adverse environmental effects.

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Notice of Alteration: New Britannia Mill