Final: ENVIRONMENTAL REVIEW REPORT FOR THE DEVELOPMENT OF THE MATTAGAMI LAKE DAM GENERATING STATION
Submitted To: Ontario Power Generation Inc.
Submitted By: SENES Consultants Limited and C. Portt & Associates
November 2010
ENVIRONMENTAL REVIEW REPORT FOR THE DEVELOPMENT OF THE MATTAGAMI LAKE DAM GENERATING STATION
Submitted to:
Ontario Power Generation Inc. 700 University Avenue Toronto, Ontario M5G 1X6
By:
SENES Consultants Limited
Prepared by: November 2010 Mr. Phil Shantz Date EA Consulting Team SENES Consultants Limited
Reviewed by: November 2010 Mrs. Gillian MacLeod Date Environmental Lead Ontario Power Generation Inc.
Approved by: November 2010 Mr. Matt MacDonald Date Project Manager Ontario Power Generation Inc.
Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
EXECUTIVE SUMMARY
Ontario Power Generation Inc. (OPG) is proposing to develop a 5 - 7 megawatt (MW) hydroelectric Generating Station (GS) (the Proposed Undertaking) in the immediate vicinity of OPG’s existing Mattagami Lake Dam. The Proposed Undertaking also includes construction of a new transmission line. This Environmental Review Report (ERR) is prepared for the Proposed Undertaking for review (by the Ontario Ministry of Environment (MOE), Ontario Ministry of Natural Resources (MNR) and other agencies. Ontario Power Generation respectfully requests acceptance of the Proposed Undertaking as described herein, under the terms of the Guide.
The Proposed Undertaking is located within the traditional territory of Mattagami First Nation (MFN). OPG and Mattagami First Nation have entered into a non-binding Memorandum of Understanding (MOU) to discuss the possibility of the parties entering into a commercial relationship with respect to the Proposed Undertaking. MFN’s Reserve is located less than 20 kilometres south of Mattagami Lake Dam.
Description of the Existing Dam and Proposed GS
The existing Mattagami Lake Dam was built in 1921 and purchased in 1944 by a predecessor company to OPG. The Mattagami Lake Dam is located at the outlet of the Mattagami Lake (at Kenogamissi Falls) on the Mattagami River, about 54 km southwest of the City of Timmins and about 20 km north of the Mattagami First Nation Reserve. The dam controls the flows from the Mattagami Lake into the Kenogamissi Lake, which is the forebay of OPG’s Wawaitin Generating Station. The dam is an important flood control facility for the City of Timmins, which is downstream of the site. The site is about 2 km east of Highway 144 and accessible by Kenogamissi Falls Road, a primary forest access road located in the extreme southern end of the Romeo Malette Forest.
The existing Mattagami Lake Dam structure includes east and west earth dykes, east and west concrete gravity walls, and a central concrete sluiceway. The overall length of the dam structure is approximately 115 metres.
The proposed GS would include a powerhouse that will enclose a single Kaplan turbine unit capable of generating 5 - 7 MW. Several similar units have already been installed and successfully operated in Canada. The proposed GS will have an average gross head of about 16 metres and design flow of about 40-47 cms depending on the final plant capacity. The proposed GS will include an intake, a penstock, a powerhouse with a tailrace channel, a powerhouse switchyard, a 3km 115 kilovolts (kV) Transmission line, and a connection switchyard (the Project). The powerhouse switchyard will be adjacent to the powerhouse to accommodate the power transformer, breaker and other electrical connection equipment. A vehicle parking lot will be located north of the powerhouse. The proposed GS will be connected
Final ES-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station to the provincial grid via an existing Hydro One 115 kilovolts (kV) Transmission line (T61S) located about 3 kilometres (km) to the east.
The proposed GS will be operated in compliance with the amended Mattagami River System Water Management Plan (MRSWMP). A minimum flow requirement has been agreed to by OPG and government agencies and would be included in the amended MRSWMP. The facility will be operated remotely and maintained by OPG’s Northeast Plant Group staff located in Timmins, Ontario. The remote control and automatic gate will facilitate faster response to changing conditions in the Mattagami Lake watershed than the current on-site log operations that are required as the flows and levels in the system change.
OPG will also construct an approximate 3 km long transmission line from the proposed generation station to Hydro One’s existing 115 kV T61S transmission line running from Timmins Transformer Station to the Shiningtree Distributing Station.
Existing Environment
The Proposed Undertaking is situated in the boreal forest on the Canadian Shield. The soil types vary from sands, gravels, clays, and boulder tills to mixtures of sand, clay and silts. Forest cover in this area is ubiquitous and dominated by typical boreal species such as black and white spruce, jack pine, trembling aspen and white birch. The proposed GS and associated transmission line will be located generally in forest ecosystem areas of mixed woods and planted spruce and jack pine plantations. Associated vegetation is typical for the boreal forest. Some wetlands and creeks occur in the wider area. Wildlife in this area is typical for boreal forest with moose and black bear being the largest land mammals. No vulnerable, rare, threatened or endangered species occur in the area of the Proposed Undertaking.
The Mattagami River is located within the Moose River drainage basin of the Hudson Bay Drainage System and traverses three physiographic regions: the Canadian Shield, the Great Clay Belt and the Hudson Bay Lowlands. The fish community in the vicinity of the proposed GS reflects the relatively simple community structure that is typical of many of the rivers in the Hudson Bay drainage basin, as well as the mainly shallow riffle habitat, with occasional deeper areas, that is present in this section of Mattagami River. The small fishes captured here are typical for this location and habitat. Logperch and longnose dace are common species inhabiting riffle habitat in riverine situations. Yellow perch are more common in Kenogamissi Lake, but some likely inhabit the slower flowing habitats of the River. The section of the Mattagami River downstream of the Mattagami Lake Dam is known as an important walleye and lake whitefish spawning area for populations of those fishes in Kenogamissi Lake. Walleye and lake whitefish are also part of the fish community in the River during their respective spawning runs and during the incubation and hatching period as embryos and fry. No species considered at-risk occurs in the vicinity of the Mattagami Lake Dam or the proposed GS.
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The area of the proposed GS is a wilderness area with light public use. Kenogamissi Falls Road is a forest access road maintained by Tembec for access to a large section of the southern part of the Romeo Malette Forest. While forest harvesting and renewal is the main economic activity, other socio-economic uses in the area include trapping, hunting, fishing and snowmobiling. A couple cottages are located within one kilometre of the site and both Mattagami and Kenogamissi Lake are popular cottaging lakes for residents of Gogama and Timmins.
Public, First Nations and Aboriginal Peoples and Government Consultation
Public, First Nations and Aboriginal Peoples, and government agency consultations have been a key part of the environmental assessment process for the Proposed Undertaking.
Public consultation has been conducted with two open houses/public meetings in Gogama and Timmins; a project website; newsletters; and the facilitation of on-going public inquiries. While the public raised several questions during the consultation process, no one voiced opposition to the Proposed Undertaking.
First Nations and Aboriginal Peoples consultation has occurred and been particularly extensive with Mattagami First Nation. Consultation has also taken place with the Métis Nation of Ontario. Offers of consultation to other First Nations were also made. As well, the Mattagami First Nation has fielded direct questions from some of these First Nations on the project. Concerns during the process by the local community councils of the Métis Nation of Ontario have been addressed through consultation and mitigation measures.
Extensive consultation has occurred with several government agencies including the Ministries of Natural Resources; Tourism and Culture; and, Environment and the federal departments of Fisheries and Oceans Canada and Transport Canada. Approximately, two years of extensive discussions occurred with the Ministry of Natural Resources (MNR) and Department of Fisheries and Oceans (DFO) on an operating regime. This culminated in an agreement over an “ecological flow”. In OPG’s view, there are no outstanding issues with these agencies with respect to the environmental assessment.
Environmental Effects of Development
This environmental assessment has examined the impact of the Proposed Undertaking on the aquatic, terrestrial, cultural and socio-economic environments.
Provided that the recommended mitigation measures are implemented, it is our opinion that the development of the Mattagami Lake Dam site, and the subsequent operation of the proposed GS, will not have a significant or measurable impact upon the composition or production of the Mattagami River fish community.
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The mitigation measures proposed to protect critical walleye and lake whitefish spawning habitats are believed to result in no net loss of spawning habitat. There will be no changes in the volume of water, and no significant changes in water velocity, passing over the critical walleye spawning habitat downstream of the powerhouse during the respective spawning and incubation periods for these species.
It is believed that the thoughtful design of the proposed GS in combination with the general mitigation measures proposed will prevent harmful alteration, disruption or destruction (HADD) of fish habitat, or a measurable change in habitat productive capacity.
The areas that will be directly altered do not serve a critical habitat function during the in-water work window and, although they do contain fish, the fact that they will be temporarily unavailable is not expected to have a significant impact on the productive capacity of the system.
Following the completion of construction the total amount of habitat is expected to be unchanged.
The impact of the Proposed Undertaking on the terrestrial environment is minimal, localized and short-term. A total of less than 12 hectares of boreal forest will need to be cleared for the Proposed Undertaking. Most of this forest cover is either mixed wood forest or re-generating conifer plantations. No species at risk were identified as being impacted by the project. No impacts are identified on wildlife populations.
During the construction of the proposed GS, potential impacts on the terrestrial environment may occur due to soil erosion and fugitive dust; accidental spills; noise and human activity; and forest/vegetation clearing. The likelihood and severity of events such as soil erosion or spills can be mitigated through the adherence to a site-specific environmental management plan which OPG will require its Contractor to develop and implement.
Environmental protection during the proposed GS construction and operation will be ensured by adherence to the site-specific Environmental Management Plan, as well as compliance with regulatory standards and guidelines. The Environmental Management Plan will include an Erosion and Sediment Control Plan, Spills Emergency Preparedness and Response Plan, Hazardous Materials Management Plan, Waste Management Plan and Site Rehabilitation Plan.
The cultural heritage assessments undertaken on the Proposed Undertaking have been done with the full co-operation of Mattagami First Nation and the Ministry of Tourism and Culture. The cultural heritage assessments have been undertaken in accordance with the Ontario Heritage Act, associated guidelines and the recommendations of Ministry staff.
The Proposed Undertaking will have a moderate economic benefit on Timmins and Gogama during the construction period of the project. As well, the project offers an excellent economic opportunity for Mattagami First Nation.
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The Proposed Undertaking is wholly consistent with the existing Crown land use direction for the area. The impact on forest resources is very minor. Only two impacts are identified on other resource users in the area. First, Kenogamissi Falls Road will need to be closed for a number of days in order to allow construction of the penstock. Appropriate notice will be required with other resource users in the area about this. Second, OPG is highly concerned with public safety at its facilities and therefore has identified that the area around the GS needs to be closed to public use. While this does not impact most resource users there are some individuals who use this area for fishing and this use would no longer be permitted. It is OPG’s opinion that it cannot compromise public safety at its facilities.
Overall, the environmental, cultural and socio-economic impacts of the Proposed Undertaking are minor and almost entirely mitigable through the measures identified in this Environmental Review Report (ERR).
Overall Benefits of the Project
The Proposed Undertaking will produce a wide variety of benefits. First, the project will add 5 - 7 megawatts of clean, renewable hydroelectric power to Ontario’s supply. Second, the project represents an economic development and employment opportunity for Mattagami First Nation. Third, the project will result in a small but important local economic benefit to the communities of Gogama and Timmins during the construction stage. Fourth, the project capitalizes on the existing infrastructure at Mattagami Lake Dam. Fifth, an ecological flow requirement has been agreed to by OPG, a requirement which is not currently in the Water Management Plan for the Mattagami River System. Lastly, all the above can be done without making any changes to the MRSWMP approved water levels on the upper (Mattagami) and lower (Kenogamissi) Lakes.
Final ES-5 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
TABLE OF CONTENTS Page No. EXECUTIVE SUMMARY ...... ES-1 1.0 INTRODUCTION...... 1-1 1.1 Introduction...... 1-1 1.2 Overview of the Environmental Review Report and Technical Support Documents ...... 1-2 1.3 Environmental Assessment Process...... 1-2 1.4 Other Environmental Approvals...... 1-4 2.0 PROJECT OVERVIEW ...... 2-1 2.1 Project Purpose...... 2-1 2.2 Project Location...... 2-1 2.3 Project Description ...... 2-4 2.3.1 Existing Site and Facilities...... 2-4 2.3.2 Proposed Undertaking...... 2-10 2.3.3 Proposed Tailrace Cofferdam Construction...... 2-18 2.4 Rationale for Location ...... 2-24 2.4.1 Rationale for Location – Generating Station...... 2-24 2.4.2 Rationale for Location – Transmission Line...... 2-26 3.0 DESCRIPTION OF THE EXISTING ENVIRONMENT ...... 3-1 3.1 Study Area and Methods...... 3-1 3.2 Terrestrial Environment ...... 3-1 3.2.1 Climatic Conditions...... 3-2 3.2.2 Geology and Soils...... 3-3 3.2.3 Forest Cover, Forest Resources and Vegetation ...... 3-4 3.2.4 Wildlife ...... 3-8 3.3 Aquatic Environment ...... 3-10 3.3.1 Regional Conditions...... 3-12 3.3.2 Local Conditions ...... 3-16 3.3.2.1 Existing Aquatic Habitat...... 3-16 3.3.2.2 Fish Community...... 3-22 3.3.2.3 Walleye Spawning ...... 3-22 3.3.2.4 Lake Whitefish Spawning ...... 3-29 3.3.3 Summary of Existing Conditions...... 3-33 3.4 Air/Noise...... 3-34 3.5 Socio-Economic Environment ...... 3-34 3.5.1 Demographics, Community and Economy ...... 3-35 3.5.2 Land and Resource Use, Access and Transportation ...... 3-36 3.6 Cultural Heritage Studies ...... 3-39 3.7 First Nations & Aboriginal Peoples...... 3-40 3.7.1 Context ...... 3-40 3.7.2 Mattagami First Nation...... 3-40 3.7.3 Matachewan First Nation...... 3-41 3.7.4 Flying Post First Nation...... 3-41 3.7.5 Wahgoshig First Nation ...... 3-41 3.7.6 Métis ...... 3-41
Final i November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
4.0 PREDICTED ENVIRONMENTAL EFFECTS AND PROPOSED MITIGATION MEASURES DURING CONSTRUCTION AND OPERATIONS...... 4-1 4.1 Potential Sources of Effects ...... 4-1 4.2 Terrestrial Environment ...... 4-1 4.2.1 Geology, Soils and Acid Rock Drainage...... 4-1 4.2.2 Forest Resources and Vegetation ...... 4-4 4.2.3 Wetlands and Environmentally Significant Areas ...... 4-6 4.2.4 Wildlife ...... 4-6 4.2.5 Summary and Conclusions...... 4-7 4.3 Aquatic Environment...... 4-9 4.3.1 Potential Construction Impacts and Associated Mitigation...... 4-10 4.3.1.1 Water Quality ...... 4-10 4.3.1.2 Aquatic Habitat ...... 4-11 4.3.2 Operational Impacts...... 4-17 4.3.3 Monitoring Plan...... 4-29 4.3.4 Summary and Conclusions...... 4-29 4.4 Air/Noise Effects...... 4-32 4.4.1 Noise ...... 4-32 4.4.2 Air ...... 4-32 4.5 Socio-Economic Environment Effects ...... 4-36 4.5.1 Demographics, Community and Economics...... 4-36 4.5.2 Land-Use Planning, Access and Transportation ...... 4-37 4.5.3 Resource Use...... 4-38 4.6 Cultural Resources Impacts ...... 4-41 4.7 Effects on First Nations and Aboriginal Peoples ...... 4-42 5.0 PUBLIC AND AGENCY CONSULTATION ...... 5-1 5.1 Consultation with Public ...... 5-1 5.1.1 Objectives and Approach...... 5-1 5.1.2 Summary of Activities ...... 5-1 5.1.3 Public Issues and Concerns ...... 5-2 5.2 Consultation with Government and Agencies...... 5-2 5.2.1 Objectives and Approach...... 5-2 5.2.2 Summary of Activities ...... 5-2 5.2.3 Agency Issues and Concerns...... 5-3 5.3 Discussions with MNR and DFO on Ecological Flow and Bedrock Pool...... 5-3 5.3.1 Introduction...... 5-3 5.3.2 Mattagami River System Water Management Plan...... 5-4 5.3.3 Existing Water Management Plan and Operating Regime ...... 5-5 5.3.4 Operating Regime of New Facility ...... 5-8 5.3.5 Summary of Changes to the Existing Water Management Plan...... 5-9 5.3.6 The Amendment Process ...... 5-11 5.4 Review of Amendment Request and Categorization of Amendment ...... 5-13 5.4.1 Types of Amendments:...... 5-13 5.4.2 OPG - Request for Minor Amendment...... 5-14 6.0 CONSULTATION WITH FIRST NATIONS AND ABORIGINAL PEOPLES ...... 6-1 6.1 Objectives and Approach ...... 6-1 6.1.1 Summary of Activities ...... 6-1 6.2 First Nations Issues and Concerns...... 6-1 6.2.1 Matachewan First Nation...... 6-1
Final ii November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
6.2.2 Flying Post First Nation...... 6-2 6.2.3 Wahgoshig First Nation ...... 6-2 6.2.4 Métis Nation of Ontario...... 6-2 6.2.5 Summary ...... 6-4 7.0 SUMMARY EVALUATION OF THE PROPOSED UNDERTAKING ...... 7-1 7.1 Advantages and Disadvantages of the Proposed Undertaking...... 7-1 7.1.1 Advantages...... 7-1 7.1.2 Disadvantages...... 7-1 7.2 Summary of Mitigation and Monitoring Commitments...... 7-2 7.2.1 Proposed Mitigation Measures ...... 7-2 7.2.2 Proposed Monitoring Measures...... 7-11 7.3 Post Environmental Assessment Approvals...... 7-11 7.4 Conclusion...... 7-19 8.0 REFERENCES...... 8-1 ACKNOWLEDGEMENTS ...... AC-1 LIST OF ABBREVIATIONS, ACRONYMS AND UNITS OF MEASUREMENT ...... AB-1 GLOSSARY ...... G-1
APPENDIX A: DISPOSITION REPORT COMMENTS
Final iii November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
LIST OF TABLES Page No. Table 2.1 Comparison of Alternatives ...... 2-30 Table 4.1 NP/AP1 Acid-Base Screening Criteria Recommended in Draft BC Guidelines ...... 4-2 Table 4.2 Summary of Potential Effects and Recommended Mitigative/ Remedial Measures ...... 4-9 Table 4.3 Mattagami River Monthly Mean Flow for the Period 1950 to 2006 at Mattagami Lake Dam (OPG data)...... 4-20 Table 4.4 Frequency of Average Daily Flow Discharged from the Mattagami Lake Dam Over the Period 1987 To 2006 ...... 4-27 Table 4.5 Summary of Potential Effects and Recommended Mitigative/Remedial Measures ...... 4-31 Table 7.1 List of Permits, Licenses and Approvals Possibly Required for Hydroelectric Redevelopment ...... 7-12
Final iv November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
LIST OF FIGURES Page No. Figure 1.1 Location of Mattagami Lake Control Dam...... 1-1 Figure 2.1 General Location of Mattagami Lake Control Dam ...... 2-2 Figure 2.2 General Location of Mattagami Lake Control Dam and Kenogamissi Falls...... 2-3 Figure 2.3 Proposed Layout for Mattagami Lake Control Dam Generating Station ...... 2-4 Figure 2.4 Scheme of Existing Mattagami Lake Control Dam...... 2-6 Figure 2.5 Existing Structures and Locations of Photographs 2-1 through 2-12...... 2-6 Figure 2.6 Existing Structures and Topography of Mattagami River Section...... 2-7 Figure 2.7 Scheme of Mattagami Lake Dam GS...... 2-11 Figure 2.8 Plan View of Conceptual Design...... 2-11 Figure 2.9 Preferred Transmission Route ...... 2-18 Figure 2.10 Sketch 1: Project General Layout ...... 2-19 Figure 2.11 Sketch 3: Powerhouse Construction Sequence – Step 1 Cofferdam Construction ...... 2-20 Figure 2.12 Sketch 4: Powerhouse Construction Sequence – Step 2 Excavation and Construction of Powerhouse Substructure...... 2-21 Figure 2.13 Sketch 5: Powerhouse Construction Sequence – Step 3 Cofferdam Removed ...2-22 Figure 2.14 Sketch 7: Tailrace Plan View ...... 2-23 Figure 2.15 Alternative Development Schemes ...... 2-25 Figure 2.16 Transmission Corridor Study Area ...... 2-27 Figure 2.17 Three Transmission Corridor Alternatives...... 2-28 Figure 2.18 Preferred Alternative – Old Utility Line...... 2-31 Figure 3.1 Terrestrial Environment Local Study Area ...... 3-2 Figure 3.2 Forest Units and Non-Productive Lands in the Study Area of the Proposed Mattagami Lake Dam GS and Transmission Line Alternatives...... 3-6 Figure 3.3 Mattagami River Watershed Generating Stations and Dams ...... 3-11 Figure 3.4 Local Study Area...... 3-12 Figure 3.5 Moose River Drainage Basin ...... 3-13 Figure 3.6 Major Physiographic Regions of the Moose River Basin ...... 3-14 Figure 3.7 Bathymetry and Topography in the Vicinity of the Proposed Generating Station (Global Surveying). The Water Edge on June 21 and on May 2 (Walleye Spawning) was Estimated from Photographs, While the Water Edge on December 11 was Determined by Total Station (Global Surveying) ...... 3-17 Figure 3.8 Substrate Type in the Vicinity of the Proposed Generating Station, Downstream to Kenogamissi Lake. The Water Edge at Four Measured Riverflows was Determined by Total Station (Global Surveying)...... 3-18 Figure 3.9 Photograph Locations and Watercourse Sections Referenced in this Report ...... 3-19 Figure 3.10 Project Study Area from Mattagami Lake to Kenogamissi Lake, Showing the Main Site Features, the Location and Basic Layout of the Proposed Hydroelectric Station, Watercourse Sections Referenced in this Report, and the Location of Photographs of the Small Watercourse Flowing from the West...... 3-20 Figure 3.11 River Reaches Examined and Number of Walleye Observed During the 2006 and 2007 Walleye Spawning Investigations. The Numbers Represent the Number of Walleye Observed in the Adjacent Area Outlined in Yellow, and Pertain to 2007 Unless Otherwise Indicated ...... 3-25 Figure 3.12 River Reaches Examined and Number of Walleye Observed During the 2008 Walleye Spawning Investigations. The Number of Walleye Observed on May 8/9, 2008, is Indicated for those Areas where Fish were Found ...... 3-26
Final v November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
LIST OF FIGURES (Cont'd) Page No. Figure 3.13 River Reaches Examined and Number of Walleye Observed During the 2009 Walleye Spawning Investigations. The Number of Walleye Observed on May 11/12, 2009, is Indicated for those Areas where Fish were Found ...... 3-27 Figure 3.14 River Reaches Examined and Number of Walleye Observed During the 2010 Walleye Spawning Investigations. The Number of Walleye Observed on April 19/April 20, 2010, is Indicated for those Areas where Fish were Found...... 3-28 Figure 3.15 Lake Whitefish Spawning Locations Between the Mattagami Lake Dam and Kenogamissi Lake. The Areas Examined for Whitefish Eggs in 2006, and the Sections of River Examined for Spawning Whitefish with an Underwater Video in 2007 and 2008, are Shown ...... 3-31 Figure 3.16 Lake Whitefish Spawning Locations between the Mattagami Lake Dam and Kenogamissi Lake. The Areas Examined for Spawning Whitefish with an Underwater Video in 2009 are Delineated in White, and the Area where Lake Whitefish were Observed is Denoted by White Hatching...... 3-32 Figure 4.1 General Project Layout...... 4-13 Figure 4.2 Initial Cofferdam Location ...... 4-14 Figure 4.3 Work-site configuration immediately prior to cofferdam removal...... 4-15 Figure 4.4 Cofferdam removal and outward extension of tailrace into river...... 4-16 Figure 4.5 Plan View of the Proposed Tailrace Works...... 4-17 Figure 4.6 Mattagami Lake Dam (1979-2009) ...... 4-19 Figure 4.7 Flow Velocities in Area B and the Upstream Portion of Area C Under Existing Conditions at a River Flow of 14 cms ...... 4-22 Figure 4.8 Flow Velocities in Area B and the Upstream Portion of Area C Under the Proposed GS Operating Conditions at a River Flow of 14 cms ...... 4-22 Figure 4.9 Area Where Typical Walleye Spawning Velocities Occur in Area B and the Upstream Portion of Area C Under Existing Conditions at a River Flow of 14 cms...... 4-23 Figure 4.10 Area Where Typical Walleye Spawning Velocities Will Occur in Area B and the Upstream Portion of Area C Under the Proposed GS Operating Conditions at a River Flow of 14 cms...... 4-23 Figure 4.11 Flow Velocities in Area B and the Upstream Portion of Area C Under Existing Conditions at a River Flow of 39 cms...... 4-24 Figure 4.12 Flow Velocities in Area B and the Upstream Portion of Area C Under the Proposed GS Operating Conditions at a River Flow of 39 cms ...... 4-24 Figure 4.13 Area Where Typical Walleye Spawning Velocities Occur in Area B and the Upstream Portion of Area C Under Existing Conditions at a River Flow of 39 cms...... 4-25 Figure 4.14 Portage and Restriction of Public Access ...... 4-40 Figure 5.1 Monthly Average Flows Released from Mattagami Lake Control Dam (1950-2006)...... 5-6 Figure 5.2 Mattagami Lake Dam Historical Operating Graph ...... 5-6 Figure 5.3 The WMP Amendment Process...... 5-12
Final vi November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
LIST OF PHOTOGRAPHS Page No. Photograph 2-1 Mattagami Lake Control Dam ...... 2-5 Photograph 2-2 Mattagami Lake Control Dam, Mattagami Lake and Safety Boom ...... 2-8 Photograph 2-3 Mattagami River from Tembec Bailey Bridge to Dam (Looking Upstream) ...... 2-8 Photograph 2-4 Mattagami Lake Control Dam to Bailey Bridge (Looking Downstream and North)...... 2-9 Photograph 2-5 Widened Area of Mattagami River Just Downstream of Bailey Bridge and Turning 90 degrees to the East ...... 2-9 Photograph 2-6 View of the 90 Degree Turn in the River from Further Downstream...... 2-10 Photograph 2-7 Dam and Intake Structure...... 2-13 Photograph 2-8, 2-9, 2-10 General Location of Penstock on Western Shoreline ...... 2-14 Photograph 2-11 Proposed Location of Powerhouse...... 2-15 Photograph 2-12 Location of Proposed Powerhouse and Tailrace ...... 2-16 Photograph 2-13 Existing Hydro One Transmission Line...... 2-17 Photograph 2-14 Proposed Hydro Transmission Line Style...... 2-17
Final vii November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
1.0 INTRODUCTION
1.1 INTRODUCTION
This Environmental Review Report (ERR) is submitted to the Ontario Ministry of the Environment (MOE) by Ontario Power Generation Inc. (OPG) for review by MOE and other agencies of a proposed 5 – 7 megawatt (MW) hydroelectric generating station (GS), (Proposed Undertaking) in the immediate vicinity of OPG’s existing Mattagami Lake Control Dam. The Proposed Undertaking also includes the construction of a new transmission line. The proposed GS would connect to the provincial grid via an existing Hydro One 115 kilovolts (kV) Transmission line (T61S) located about 3 kilometres (km) to the east.
OPG and Mattagami First Nation have entered into a non-binding Memorandum of Understanding to discuss the possibility of the parties entering into a commercial relationship with respect to the Proposed Undertaking.
Figure 1.1 Location of Mattagami Lake Control Dam
This ERR and associated Technical Support Documents have been prepared pursuant to the Guide to Environmental Assessment Requirements for Electricity Projects (March 2001).
This document is the product of over four years of extensive study and consultation with Mattagami First Nation, the general public and government agencies. This report and the
Final 1-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station associated technical support documents were prepared by SENES Consultants Limited (SENES) with the assistance of Ontario Power Generation and a number of sub-consultants.
1.2 OVERVIEW OF THE ENVIRONMENTAL REVIEW REPORT AND TECHNICAL SUPPORT DOCUMENTS
This Environmental Review Report (ERR) is segmented into seven chapters. This chapter, Chapter 1 introduces the report and supporting technical documents and outlines the environmental assessment process. Chapter 2 provides an overview of the project including a detailed project description and a rationale for the project’s location. Chapter 3 provides the description of the existing environment. Chapter 4 provides an overview of environmental effects and mitigation measures during construction and operations. Chapter 5 provides an overview of public and government agency consultation. Chapter 6 summarizes First Nations and Aboriginal Peoples consultation. Chapter 7 provides an overall summary evaluation of the undertaking. Acknowledgements, lists of abbreviations, acronyms and units of measurements together with a glossary are also included. Appendix A includes comments from agencies made during a voluntary agency review prior to the public review.
This ERR is supported by several technical support documents as following:
• Aquatic Environment Technical Support Document; • Terrestrial Environment Technical Support Document; • Socio-Economic and Land Use Technical Support Document; • Public and Agency Consultation Technical Support Document; • Transmission Line Assessment Technical Support Document; • First Nations & Aboriginal Peoples Consultation Technical Support Document; and, • Cultural Heritage Studies.
1.3 ENVIRONMENTAL ASSESSMENT PROCESS
This ERR has been prepared pursuant to the Guide to Environmental Assessment Requirements for Electricity Projects (March 2001). The Guide to Environmental Assessment Requirements for Electricity Projects contains a Chart identified as the “Electricity Project Classification” (p. 9) for all types of energy projects (e.g., natural gas, transformer stations, hydroelectric). According to the Guide, all hydroelectric projects under 200 megawatts (MW) are subject to the “Category B: Environmental Screening Process”. As well, transmission lines associated with Category B generation projects and equal to or greater than 115 kV are also part of the Category B Environmental Screening Process. As the proposed Mattagami Lake Development Project at 6 MW is fewer than 200 MW and contains a short 115 kV transmission component of approximately 3 kilometres the project is subject to the Category B Environmental Screening Process.
Final 1-2 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
For the purpose of assisting in how the Guide was applied to the project some key aspects of the project are noted. A Water Management Plan is already in place for the Mattagami River System and was approved by the province in 2006. The Proposed Undertaking and the Water Management Plan are discussed in more detail in Chapter 2. The Mattagami Lake Dam Hydroelectric Project is based on OPG having in place an existing control dam at the site. As such, the site was not part of MNR’s Waterpower Site Release program. While an existing control facility is in place, there are no hydroelectric generating facilities or infrastructure and therefore the project should be treated as a “New Hydroelectric Facility”.
With respect to transmission, the Guide indicates that:
“Transmission lines that are 115 kV or greater, and are associated with a generation facility that falls in Category B are to be reviewed through the Environmental Screening Process so that the entire project can be reviewed under one process, as a single project. Proponents of such transmission lines are encouraged to examine and evaluate different routes as part of their review under the Environmental Screening Process.” (p. 15)
Following the direction suggested in the Guide, OPG examined a variety of possible transmission corridors and routes before selecting its preferred route. The proposed transmission line would exclusively occupy Crown land. The transmission corridor and route selection process is described in this ERR and also in the Transmission Line Assessment Technical Support Document with supporting evidence also provided in the Terrestrial Environment Technical Support Document.
Following the Environmental Screening Process laid out in the Guide (Section B.3, p. 35), the project was first assessed by OPG at a Screening Stage. However, very early into that stage it was recognized that there were environmental issues that could not be readily resolved without more detailed studies and therefore OPG voluntarily moved into the Environmental Review stage. Therefore, no Screening Report was prepared. The Environmental Review for the project was carried out according to the specifications identified in B.3.2 of the Guide and this report prepared according to direction in section B.3.3.
Consultation with agencies, primarily the Ministry of Natural Resources Timmins District office, the Department of Fisheries and Ocean and the Ministry of Culture has been ongoing and assisted in the Environmental Review stage from late 2006 through 2010.
Public consultation has been ongoing through the project and was formally initiated in June 2007 meeting the Guide’s mandatory public notification requirements. Two rounds of open houses were held. The first open house was held in June in Gogama. A second round of open houses was held in November in Gogama and Timmins.
Final 1-3 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
First Nations and Aboriginal Peoples consultation on the project has occurred since the project was initially conceived. The Mattagami First Nation took the initial step in launching the project by asking OPG if it was interested in possibly developing this project in partnership with the First Nation. Since that time, consultation with Mattagami FN has been ongoing and comprehensive both with the leadership of the FN and the broader community. Consultation has also been offered to other area First Nations.
Details about the public, agency and First Nations and Aboriginal consultation program are described in Chapters 5 and 6 in the supporting Technical Support Documents. It is OPG’s opinion that these reports and documentation easily surpass the “Documentation” requirements outlined in the Guide.
Upon completion of this Environmental Review Report a Notice of Completion and Statement of Completion will also be prepared and advertised in local papers.
1.4 OTHER ENVIRONMENTAL APPROVALS
Other permits, approvals and clearances will be sought as the project moves into the construction stage. Chapter 7 of this report identifies a full range of possible approvals required; however, specific permits and approvals will likely be required under the Lakes and Rivers Improvement Act, Environmental Protection Act and clearances under the Navigable Waters Protection Act.
Final 1-4 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
2.0 PROJECT OVERVIEW
This Project Overview includes a description of the Proposed Undertaking and a rationale for the location of the project.
2.1 PROJECT PURPOSE
Ontario Power Generation Inc. (OPG) is proposing to develop a 5-7 megawatt (MW) hydroelectric generating station (GS) (Proposed Undertaking), in the immediate vicinity of OPG’s existing Mattagami Lake Control Dam. The Proposed Undertaking also includes construction of a new transmission line. The proposed GS will be connected to the provincial grid via an existing Hydro One 115 kilovolts (kV) Transmission line (T61S) located about 3 kilometres (km) to the east.
OPG and Mattagami First Nation have entered into a non-binding Memorandum of Understanding (MOU) to discuss the possibility of the parties entering into a commercial relationship with respect to the Proposed Undertaking.
2.2 PROJECT LOCATION
The existing Mattagami Lake Dam is located at the outlet of Mattagami Lake (at Kenogamissi Falls) on the Mattagami River, about 54 km southwest of the City of Timmins and about 20 km north of the Mattagami First Nation Reserve. The dam controls the flows from Mattagami Lake into Kenogamissi Lake, which is the forebay of OPG’s Wawaitin Generating Station. The dam’s latitude and longitude are N48o 00’ 48”, W81o 33’ 30”, respectively. The site is about 2 km east of Highway 144 and accessible by Kenogamissi Falls Road (a primary forest access road) as shown in Figure 2.1.
Final 2-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Figure 2.1 General Location of Mattagami Lake Control Dam
Figure 2.2 shows the location of the Proposed Undertaking with respect to the Hydro One transmission Line, existing roads and natural, physical and human features. Figure 2.3 shows the proposed layout for the Mattagami Lake control dam generating station.
Final 2-2 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Figure 2.2 General Location of Mattagami Lake Control Dam and Kenogamissi Falls
Final 2-3 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Figure 2.3 Proposed Layout for Mattagami Lake Control Dam Generating Station1
2.3 PROJECT DESCRIPTION
2.3.1 Existing Site and Facilities
The existing Mattagami Lake Dam (Photograph 2-1) was built by Northern Power Company in 1921 and acquired by Hydro-Electric Power Commission of Ontario (HEPCO) in 1944. It is currently owned and operated by OPG (the successor to Ontario Hydro which is the successor to HEPCO). The dam controls the flows from Mattagami Lake into Kenogamissi Lake. Mattagami Lake provides flood mitigation for the City of Timmins as it has the largest storage capacity on the Upper Mattagami River system.
1 The intake, penstock, powerhouse and tailrace are exaggerated for illustrative purposes in the maps
Final 2-4 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Photograph 2-1 Mattagami Lake Control Dam
The dam consists of the following structures: east earth dyke, east concrete gravity wall, central concrete sluiceway, west concrete gravity wall and west earth dyke. The overall length of the dam is approximately 115 metres.
The centre sluiceway is 40 metres long and 9 metres high and consists of six sluices with a total discharge capacity of 524 cubic metres per second at reservoir water level of 331.48 metres (all levels and elevations are referred to Canadian Geodetic Datum). Sluices #3 and #4 are equipped with underwater ports to assist in winter drawdown operations.
The east concrete gravity wall extends from the #6 sluice side pier to the east earth dyke. It is 19 metres long and 0.9 metres wide at the crest with a maximum height of 7.6 metres. A vertical concrete core wall extends into the east earth dyke which is 13 metres long.
The west concrete gravity wall extends from the #1 sluice side pier to the west earth dyke. It is 16 metres long and 4 metres wide at the crest with an average height of 7 metres. A vertical concrete core wall extends into the west earth dyke which is 27 metres long.
Final 2-5 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Figure 2.4 Scheme of Existing Mattagami Lake Control Dam
Figure 2.5 shows the existing structures and locations of photographs presented in this project description.
Figure 2.5 Existing Structures and Locations of Photographs 2-1 through 2-12
Photo 2-2 Kenogamissi Dam Road from Hwy 144
Photo Photo Photo 2-7 2-11 2-10 Photo Photo Photo Photo Photo 2-3 2-12 2-6 2-8 2-1 Photo Photo 2-4 Photo 2-9 2-5 Existing Control Bridge N Dam
Mattagami River
to Wawaitin GS
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The existing Mattagami Lake Dam was constructed immediately upstream of the Kenogamissi Falls. A primary forest access road and a bailey bridge (owned by Tembec) is located about 150 metres downstream of the dam. The west river bank between the dam and the bridge is relatively steep, while the east river bank has a gentle slope. Downstream of the road and bridge, a creek merges into the river from the west side. The area between the road and the creek is relatively flat and will accommodate the future powerhouse and switchyard.
The slope of the river bed from downstream of the dam to the bridge is relatively steep with an elevation variation of about 12 metres. A series of bedrock outcrops between the control dam and the bridge are visible during low flows.
The Mattagami River in this location generally runs from south to north. Water flows northward from Mattagami Lake through the control dam and turns 90 degrees about 50 metres downstream of the bridge to the east and runs about 550 metres before merging into Kenogamissi Lake. The existing structures and general topography around the Mattagami Lake Dam are illustrated in Figure 2.6. The slopes in this area are typically covered with adequate soil overburden and vegetated with mature trees and undergrowth.
Figure 2.6 Existing Structures and Topography of Mattagami River Section
Final 2-7 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Photograph 2-2 Mattagami Lake Control Dam, Mattagami Lake and Safety Boom
Photograph 2-3 Mattagami River from Tembec Bailey Bridge to Dam (Looking Upstream)
Final 2-8 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Photograph 2-4 Mattagami Lake Control Dam to Bailey Bridge (Looking Downstream and North)
Photograph 2-5 Widened Area of Mattagami River Just Downstream of Bailey Bridge and Turning 90 degrees to the East
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Photograph 2-6 View of the 90 Degree Turn in the River from Further Downstream
2.3.2 Proposed Undertaking
Preliminary assessments conducted by OPG indicate there is a potential for a small hydroelectric development at this site, with its operation consistent with how the River is currently managed. While several options were examined, the Proposed Undertaking is a single-unit generating station (GS) having an installed capacity of 5 to 7 MW, with an average gross head of about 16 metres and design flow of about 40-47 cubic metres per second (cms) pending on the final plant capacity.
The Proposed Undertaking will include an intake canal, intake structure, penstock, powerhouse with a tailrace channel, powerhouse switchyard, 3 km 115 kilovolts (kV) transmission line, and a connection switchyard near the existing Hydro One 115 kilovolts (kV) Transmission line (T61S). The major components noted above are shown in the following sketch:
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Figure 2.7 Scheme of Mattagami Lake Dam GS
The preliminary concept of the Proposed Undertaking is depicted below.
Figure 2.8 Plan View of Conceptual Design
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Intake Canal and Intake
The new intake will be located downstream of the west end of the sluiceway to utilize the existing first two sluices. The intake channel will have an approximate footprint of 12 metres by 25 metres, with a maximum depth of approximately 12 metres. A new automated sluice gate will be installed downstream of Sluice #3 to facilitate the remote operation of the dam.
The existing piers #1 and #3 need to be extended downstream approximately 12 metres to connect to the new intake structure. It is OPG’s intention to utilize the existing stoplogs at Sluice #1, #2 and #3 as the upstream cofferdam for construction of the new intake structure and the new automated sluice gate at sluice #3. Sluices #1, #2 and #3 will be shut down and sealed during the construction period. If the stoplogs cannot be completely sealed, an alternative means such as the use of membranes can be installed to manage leakage through those stoplogs. The area immediately downstream is expected to be dry because the riverbed in that area is at a higher elevation. The remaining three sluices (#4 to #6) will be utilized to pass any necessary flow discharge in order to optimize site safety. As an additional safety measure, a board system will be installed at the water side of the new intake during the construction period. This will protect the construction pit from spill over or backwater from other sluices. There will be rock blast and concrete placement for the intake construction. All the work will be done in dry conditions in compliance with applicable guidelines, standards and regulatory requirements. A sluicegate, emergency gate, headgate and a set of trashracks will be installed after the concrete work. The remains of the old timber dam shown in Photograph 2-7 will be removed to streamline the flows approaching the new intake.
The discharge capacity of Sluices #3 - #6 will be 351 cms (close to the Inflow Design Flood (IDF) of 361 cms for 100 years). As a further Dam Safety measure, the new intake will also include a stop log sluice with an additional discharge capacity of 130 cms, which brings the total discharge capacity to 481 cms and greater than the 1,000 year IDF of 479 cms.
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Photograph 2-7 Dam and Intake Structure
New Intake
Remains of old timber crib dam
Penstock
A steel penstock with a diameter of about 4 metres and a length of 150 metres will then convey water along the western bank of the river and run under the existing road to a powerhouse, which would be located in the vicinity north of the existing Bailey bridge on the western bank of the river (Photographs 2-8, 2-9, 2-10).
The steel penstock will be placed on concrete saddles. The overburden and rock excavation will be undertaken in dry conditions. There will be no in-water blasting and all rock blasting will follow DFO Guidelines.
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Photograph 2-8, 2-9, 2-10 General Location of Penstock on Western Shoreline
East West Bank Bank
Penstock Penstock West Bank Intake
Flow
Penstock West Bank
Powerhouse, Tailrace Channel and Powerhouse Switchyard
There will be a switchyard adjacent to the powerhouse to accommodate a main power transformer and associated structures and devices. The powerhouse switchyard will be approximately 20 metres by 35 metres. A vehicle parking lot will be located north of the powerhouse with a footprint of approximately 15 metres by 20 metres.
Final 2-14 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Photograph 2-11 Proposed Location of Powerhouse
The powerhouse will accommodate a single Kaplan turbine unit. Several similar units have already been installed and successfully operated in Canada. Based on their track record, it is anticipated that this type of unit will most efficiently harvest the water power available at this site. The water from the turbine will be first discharged into the tailrace channel then into the river. The tailrace channel will flare out in order to reduce the exit velocities to acceptable levels (Photograph 2-12).
While final engineering is not completed yet, the powerhouse superstructure is likely to be a prefabricated steel building with metal-clad surface finish. The superstructure’s approximate dimensions are 15 x 17 x 12 metres (W x L x H). About 17 metres deep excavation will be required in order to construct the powerhouse concrete substructure and tailrace channel.
The powerhouse and part of the tailrace channel will be constructed in dry conditions inside a cofferdam located along the west shoreline. The cofferdam will be designed and constructed to safely resist the flood design criteria for the construction period. The cofferdam will be removed after the first phase construction of the powerhouse and installation of the tailrace sectional gates. The tailrace channel will be completed and the riverbed will be reshaped during the low flow period when the control dam can be shut down allowing only leakage flow. The potential shoreline that may be reduced due to the cofferdam construction is estimated at 150 m2. Approximately 500 m2 of shoreline area may need to be reshaped. See the Aquatic TSD for further information.
Final 2-15 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
All equipment associated with the generating station operation will be installed in the second phase of the powerhouse construction along with the powerhouse switchyard.
Photograph 2-12 Location of Proposed Powerhouse and Tailrace
Powerhouse
Small Creek
Tailrace
Transmission Line and Connection Switchyard
The proposed 3 km 115 kilovolts (kV) transmission line will run from the powerhouse switchyard to the connection switchyard near the existing Hydro One 115 kV Transmission line (T61S) (Photograph 2-13) running from Timmins Transformer Station to the Shiningtree Distributing Station. The connection switchyard will contain a motorized disconnect switch and associated structures and devices.
The final tap line from the connection switchyard to the existing Hydro One 115 kV Transmission line (T61S) will be constructed by Hydro One. The transmission line will be built to the CAN/CSA-C22.3 No. 1-06 standard.
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Photograph 2-13 Existing Hydro One Transmission Line
The proposed transmission line will be a 115 kV single or double wooden pole transmission line. A single wooden pole line is shown in the photograph below and the proposed line would resemble this design (Photograph 2-14) or a double wooden pole type of similar height.
Photograph 2-14 Proposed Hydro Transmission Line Style
A preferred transmission corridor has been identified and is depicted in Figure 2.9. This corridor follows an old utility line. This corridor (right-of-way) is approximately 3 km long and will be about 40-45 metres in width.
Final 2-17 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Figure 2.9 Preferred Transmission Route
2.3.3 Proposed Tailrace Cofferdam Construction
The construction methods of the tailrace cofferdam presented here outline the basic principles that will be used to minimize the environmental impact. Components of the Department of Fisheries and Oceans (DFO) Risk Management Framework were used to assess the proposed tailrace cofferdam construction and were discussed with Connie Smith at a meeting in the Sudbury DFO offices on November 13, 2008. Generally, the powerhouse and part of the tailrace channel will be constructed in dry conditions inside a cofferdam located along the west shoreline.
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Figure 2.10 Sketch 1: Project General Layout
The tailrace cofferdam will be constructed along the west shore of the river, downstream from the road bridge. The construction will occur in the dry over a period of 3 to 4 weeks during the low flow period, when the existing Mattagami Lake Control Dam can be shut down with only leakage flow to the downstream river. No in-water work will occur in the tailrace area during the spawning or incubation periods of walleye or lake whitefish (i.e. the cofferdam construction should normally be done between June 20 and September 15). The cofferdam’s toe on the river side will be placed roughly to just below the waterline associated with the average annual flow of 30 cms, and at that water level, the wetted habitat area would be reduced by approximately 150 m2. The cofferdam will stay in place for about 2 years and be designed according to the latest Ontario Dam Safety Guidelines. The habitat area, that will temporarily be unavailable to fish during this period, is not spawning habitat for lake whitefish or walleye.
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Figure 2.11 Sketch 3: Powerhouse Construction Sequence – Step 1 Cofferdam Construction
During the excavation and initial construction of the powerhouse and part of the tailrace channel, the excavation pit will need to be maintained in a dry condition. Surface water and leakages will be collected and pumped from the pit to a settling pond or a filter bag, or a combination of both, to remove as much suspended material as possible from the discharge water before it re-enters the river. Contouring and shaping of the tailrace channel will be conducted in the dry behind the cofferdam to the extent possible. Once the powerhouse is advanced to the point that its outer shell within the pit is finished and watertight, and the draft tube gates can be sealed, the cofferdam can be removed.
Final 2-20 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Figure 2.12 Sketch 4: Powerhouse Construction Sequence – Step 2 Excavation and Construction of Powerhouse Substructure
The cofferdam will be removed during the traditional low flow period, and during the accepted in-water work window (i.e. June 20 and September 15) as indicated earlier. The existing Mattagami Lake Control Dam will be closed, allowing only leakage during the 2 to 3 week duration of this work. This should result in water levels that are low enough for the cofferdam to be removed in the dry (Figure 2.13). As the cofferdam is removed, the contouring and shaping of the tailrace can be extended outward as much as possible in the dry.
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Figure 2.13 Sketch 5: Powerhouse Construction Sequence – Step 3 Cofferdam Removed
The tailrace extension into the river will require the re-contouring of approximately 500 m2 of riverbed to allow for the efficient flow of water exiting the tailrace. Figure 2.14 is a plan view of the tailrace with cofferdam, showing the estimated extent of the tailrace contouring and shaping that will be required to smooth the transition between the tailrace to the river. At the point in time when work in the wetted portion of the river cannot be avoided, a silt curtain system will be installed to enclose the tailrace footprint area. For such a small amount of excavation within relatively clean granular substrates, a silt curtain system, rather than a second cofferdam, will be the best choice to minimize impacts to the surrounding habitats. Utilizing a new cofferdam, rather than a silt curtain, would extend the area of direct impact to include the base of the cofferdam, possibly resulting in a doubling of the area of riverbed disturbed, and increasing the duration of that disturbance. Within the area contained by the silt curtain system, the tailrace can be deepened and extended to blend with the contours of the surrounding riverbed. Backhoe bucket movement speed can be adjusted to minimize the suspension of material when warranted. The native riverbed material will be used to re-contour the in-water area as shown in Figure 2.14, with the coarser materials (cobble/small boulder) placed along the edge and sloped sides of the tailrace to provide potential spawning areas for walleye, and the finer materials (sand/gravel) placed in the deeper central portions of the tailrace to provide potential spawning areas for lake whitefish. Once the tailrace construction is complete, and all potentially erodible areas are stabilized and fine suspended material is cleaned-up, the tailrace silt curtain will be removed.
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Figure 2.14 Sketch 7: Tailrace Plan View
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2.4 RATIONALE FOR LOCATION
Described below is the rationale for the development of the proposed GS at Mattagami Lake Dam and the specific location of work.
2.4.1 Rationale for Location – Generating Station
As indicated in the Project Description the existing Mattagami Lake Dam was built by Northern Power Company in 1921, prior to Ontario Hydro acquiring the site in 1944. An archival drawing of the site dated to 1923 indicated that the Northern Power Company had contemplated putting in a generating station connecting sluice gates #5 and #6 with a penstock running along the eastern shoreline and a generating station at the bottom of the falls. For reasons unknown to OPG the facility was never built. That being said, the existing dam provides flood mitigation for the City of Timmins as it has the largest storage capacity on the Upper Mattagami River system.
In 2005 several factors came together for OPG to consider development at the site:
• First and foremost, the Mattagami First Nation approached OPG about potentially developing the site for a generating station in partnership with them; • OPG recognized that it had already in place a control dam and operational site making development more feasible; • The Water Management Plan for the Mattagami River System was being completed; and, • The Government of Ontario identified the need for more power and specifically hydroelectric power.
Based on the above factors, OPG initiated engineering and environmental studies to explore the feasibility of developing the site.
OPG explored four basic alternatives for locating the Generating Station which are shown below in Figure 2.15. These alternatives were discussed in great detail with Mattagami First Nation and all four were presented to a meeting with the Ministry of Natural Resources and Department of Fisheries and Oceans on November 21, 2006.
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Figure 2.15 Alternative Development Schemes
Mattagami Road from Lake Hwy 144 Powerhouse Penstock Intake for 2 Tailrace Alt.1&2 Bridge 1
4
Existing Intake for Control Alt.3&4 Dam 3 N
MATTAGAMI LAKE DAM DEVELOPMENT PROJECT
Mattagami Alternative Development River to Wawaitin Schemes GS
Alternative 1, shown in the above Figure held several disadvantages. First, this alternative was viewed as uneconomic as it would have only produced about 3.5 MW of power and would have failed to take advantage of all the available head. Second, this alternative was viewed as very difficult to construct with large excavations being required on land and into the middle of the falls. This had associated environment and health and safety risks during construction. Third, this would have produced a backwater effect on the existing bridge and potentially threatening the stability of the structure. For all the above reasons, this alternative was not considered viable.
Alternative 2 was seen to have several advantages. First, it was viewed as economically viable given capacity and energy estimates. Second, a large area was available for construction around the powerhouse and intake. Third, the existing Kenogamissi Falls Road would provide easy access to the intake and powerhouse. Fourth, it would have a streamlined tailrace. Fifth, the impact on fish spawning habit was considered mitigable through further design. The only disadvantage cited with this alternative was that it would result in restricted access for fishing in this area.
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Alternative 3 was seen to have only two advantages and several disadvantages. The first advantage was that the work on the intake would eliminate the need for rehabilitation of the east concrete gravity wall of the dam. The second advantage was that it would require only a minimal amount of excavation. The first disadvantage was that this option would require the use of the bridge. The second disadvantage was that there were limited spaces for construction around the intake and the powerhouse. The third disadvantage was that there would be no road access to the intake. The fourth disadvantage was that it would have the highest impact on fish habitat as the tailrace would be placed in the middle of the spawning habitat and also a dry area would be created in the area from the bridge to the GS. The fifth disadvantage was that it was considered less economic as production of electricity would need to be altered as a result of various ecological requirements.
Alternative 4 had many of the same advantages and disadvantages of Alternative 3. The first advantage was that the work on the intake would eliminate the need for rehabilitation of the east concrete gravity wall of the dam. The second advantage was that it would require only a minimal amount of excavation for the penstock. The first disadvantage was that this option would require the use of the bridge. The second disadvantage was that there were limited spaces for construction around the intake and the powerhouse. The third disadvantage was that there would be no road access to the intake. The fourth disadvantage was that it would discharge into the middle of the spawning habitat.
Based on the analysis presented above, Alternative 2 was considered the best alternative that married economic viability with constructability with least impact on the environment. The selection of Alternative 2 as the go forward alternative was decided at the November 21, 2006 meeting with DFO and MNR, recognizing that the design could be tweaked so as to lessen the impact on fish habitat.
Subsequent work by the OPG engineering and environmental consultants and consultations with MNR and DFO results in re-orienting the powerhouse and tailrace so that it was on a 90 degree angle to the river channel. This together with tailrace design was considered to produce only a negligible impact on the fish spawning area in this reach of the river. The final design is shown and discussed in the Project Description.
2.4.2 Rationale for Location – Transmission Line
The location of the proposed 115 kV transmission line that would link the powerhouse to the existing 115 kV Hydro One transmission line was determined through a transmission corridor siting process, which is outlined in detail in the Technical Support Document, “Transmission Line Assessment for the Mattagami Lake Dam Project.” Figure 2.16 below shows the broad study area for the siting of the transmission line.
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Figure 2.16 Transmission Corridor Study Area
Based on that broad study area, three transmission corridor alternatives were identified. The three alternatives examined were:
• Alternative #1 – Follow the Road; • Alternative #2 – Old Utility Line; and, • Alternative #3 – Straight Line to the Northeast.
All three of these corridors are depicted in Figure 2.17 below.
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Figure 2.17 Three Transmission Corridor Alternatives
The major advantages and disadvantages of each of the alternative corridors are presented below.
Alternative #1 – Following the Road
Advantages • Close proximity to the road for construction and maintenance. • Less impact on contiguous forest covers than Alternative #3.
Disadvantages • Longest route and therefore the most costly to construct and maintain. • Longest route and therefore has quantitatively the most significant impact on clearing of forest cover and vegetation. • Requires the widest crossing of the stream/wetland near the Hydro One corridor. This will require some in-water works; therefore, increases risk of potential impact to the aquatic ecosystem. • May cause disruptions to vehicular traffic during construction. • May present more of a risk to vehicular traffic during operational phase.
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Alternative #2 – Old Utility Line
Advantages • Shortest route when considering terrain and therefore the least expensive to construct and maintain. • Shortest route and quantitatively the least significant impact on clearing of forest cover and vegetation. • Re-uses the disturbed corridor (site and forest cover disturbed). • No sensitive environmental features or values noted along corridor. • Generally situated close to Kenogamissi Dam Road and the Clay/Mineral trace road for access. • Water crossing on the eastern end of the corridor is the shortest and will not require in- water work as access is available from both sides.
Disadvantages • Located further from Kenogamissi Falls access road than Alternative #1. • This alternative is in close proximity to a bear stand but this is not a recognized Natural Resource Values Information System (NRVIS) value and it is unlikely that the stand is physically impacted.
Alternative #3 – Northeast Alternative
Advantages • As a straight line it is the shortest route. However, considering the undulating terrain it is actually longer than Alternative #2.
Disadvantages • Crosses the most rugged terrain. This is particularly challenging closer to the proposed GS with respect to constructability and cost. • As it crosses the highest terrain it will have the most negative effect from a visual perspective. • Disturbs more un-disturbed forest (segments contiguous forest cover). • Water crossing more difficult than Alternative #2 but easier than #1. • Least preferred alternative with respect to proximity to access roads.
Common Factors for All Alternatives
The following characteristics are considered common to all the alternatives.
• All three alternatives occur in largely the same forest ecosystem habitats with similar forest age class structures. • Near the Hydro One Transmission line, all three alternatives must climb higher terrain.
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Comparative Analysis
The following factors were considered in the analysis of possible corridors:
• Capital Cost – As the line is built to the same standard, the preferred capital cost is the one with the shortest line and closely situated access roads. • Operating Cost – The preferred operating cost is for the shortest line and closely situated access roads. • Technical – The preferred technical alternative is for the flattest terrain and avoidance of water features (e.g., water bodies and wetlands). • Environmental and Social Considerations – The preferred environmental and social alternative is the one that is: shortest; and, impacts the fewest number of environmental features and values.
Each alternative was ranked 1 to 3 for all criteria, with 1 representing the preferred ranking for that particular criterion. Where alternatives are similar a common score of 2 is given. The lowest score is the preferred alternative.
Table 2.1 Comparison of Alternatives Alternative 3 – Alternative 1 – Alternative 2 – Criteria Northeast Road Old Utility Line Alternative Capital Cost 2 1 2 Operating Cost 2 1 2 Technical 2 1 2 Environmental and 3 1 3 Social Considerations Score 9 4 9
As indicated in the above table the preferred and selected alternative was the old utility line.
Within that broader corridor of the old utility line, further detailed analysis was undertaken to more clearly identify the preferred alignment. More detailed analysis was undertaken with respect to forest resources, terrestrial biology and other factors. The more detailed analysis revealed very little difference between alternative alignments within this broader corridor. The forest resources and ecology were considered to be the same with all possible alignments and therefore no difference could be cited for choosing one alignment over another. Therefore, in the end it was decided to follow exactly the old utility line, which is depicted in Figure 2.18 below.2
2 The only slight variation on the old corridor is that the old transmission is believed to have originated close to the dam versus the proposed location near the powerhouse. The old and proposed transmission corridors meet about 100 metres east of the Mattagami River.
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Figure 2.18 Preferred Alternative – Old Utility Line
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3.0 DESCRIPTION OF THE EXISTING ENVIRONMENT
3.1 STUDY AREA AND METHODS
Study areas were selected for each major component of the natural and socio-economic environment. This selection was based on a preliminary assessment of the areas that were expected to be affected directly or indirectly by the Proposed Undertaking.
Data sources used to document the existing environment included: published and unpublished literature, government files, personal interviews, public open houses and field studies. Where possible, existing data sources were used; however, extensive field studies were required to complete the study. Principal methods for the research are documented in the Technical Support Documents for the various disciplines.
3.2 TERRESTRIAL ENVIRONMENT
A regional area and a local study area were identified for the terrestrial component of the biological studies. The regional study area is generally defined by the Mattagami River watershed and provides for the baseline description of climate, geology and physiography. The local study area encompasses the areas possibly affected by the construction and operation of the proposed GS and transmission line. This local study area is shown in Figure 3.1 below. The local study area provides for the environmental baseline description of soils, vegetation, wildlife and environmentally sensitive areas.
Final 3-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Figure 3.1 Terrestrial Environment Local Study Area
3.2.1 Climatic Conditions
The Proposed Undertaking is situated in the Canadian Boreal Shield Ecoregion, Lake Temiscaming Lowland (EC 2008a). The climate of this region of Northeastern Ontario is classified as “modified continental”, moderated by the Great Lakes (Lake Huron and Georgian Bay) to the south and, to a lesser extent, by Lake Superior to the west and Hudson Bay to the north (Chapman and Thomas 1968). The modified continental climate is characterized by short, warm summers and long, cold winters, with moderate precipitation. In summer, warm humid air masses from the south alternate with cooler, drier air masses from the north to produce periods of clear, dry weather followed again by warm, humid weather. Winters are characterized by snow squalls and high winds alternating with clear, cold, dry weather.
Based on Environment Canada, National Climate Archive (EC 2008b), the climatic data available for the City of Timmins is the closest information available for the proposed development site. Timmins has a relatively cool climate with a mean annual temperature of 1.3°C. Temperature ranges from an extreme low of -45.6°C to an extreme high of 35.6°C.
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Precipitation in Timmins is uniformly distributed throughout the year with no pronounced wet or dry seasons. Highest monthly precipitation (9.2 centimetres) occurs in July, with the highest average snow depth (65.4 centimetres) occurring in December. The average annual precipitation is 83.1 centimetres with 55.8 centimetres falling as rain, the balance as snow. Average annual snowfall is 31.3 centimetres. Summer rainfall (June to September) is approximately 34.9 centimetres (ACNBC 1980).
3.2.2 Geology and Soils
The Proposed Undertaking is located in the Abitibi Upland subregion of the Precambrian Canadian Shield Physiographic Region (Barnett 1992). It is also located just south from the maximum extent of the glacial Lake Ojibway-Barlow deposits (Sears 1992). Deglaciation at that location occurred 10,000 years ago, while for Timmins it is evaluated at 9,000 years ago (Barnett 1992).
The area is underlain by massive, crystalline, acidic, Archean bedrock. The surficial terrain is largely of glacial deposits, forming hummocky and undulating, broadly sloping uplands and lowlands. The proposed development lies within Hills’ Site Region 3E: Lake Abitibi and Site District 3E5 (Hills 1959). The site region is an area of land within which the response to vegetation to the features of landform (relief and geological materials) follows a consistent pattern. Site Region 3E is characterized by moderately to gently rolling bedrock, generally covered by deep deposits of clay, silt and sand. Site District 3E5 is typified by gently rolling plains of thinly covered rock knobs, sandy outwash and silty depressions. The materials are generally granite. All texture and drainage classes are found in 3E5, with only 18% of the area in peat land (Tembec 2006).
The main four types of surface geological deposits are glacio-lacustrine, glaciofluvial, morainal till, and organic.
The soil types vary from sands, gravels, clays, and boulder tills to mixtures of sand, clay and silts. As expected, organic soils are found in the low lying areas. The elevation in the study area ranges from about 335 metres above sea level (asl) at the Mattagami River and on the creek to the east to 381 metres asl at the centre of the study area. The topography is moderately rolling with occasional ridges. Drainage is generally good due to the topography, and the permeable soils.
At the proposed GS property, the soil deposits are loose, greyish brown silt, with traces of sand and clay. A granitic boulder layer, with cobbles and gravel in a sandy matrix covers the bedrock (BPR Energie 2007). Bedrock depth ranges from 1.0 to 6.2 metres. Bedrock consists mainly of grey and pink granite, with felsic and dioritic dykes and quartz and feldspar veins.
Geology, soil and site conditions have implications, which must be taken into account when siting a proposed development. The topography is more rolling on the west and east sides of
Final 3-3 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station the proposed development with lowland areas and streams alternating between the uplands. The central portion of the proposed development is generally flat.
Bald earth imagery (ground without trees) produced using LIDAR Digital Elevation Model provides a summary of the topography for the study area. The study area can be divided into four main topographic areas. On the west side, the Mattagami River has the lowest elevation at values between 320 and 330 metres asl. This is expected, as this is the main drainage for the Mattagami watershed. In the central portion, the topography rises about 30 to 40 metres, an elevation between 347 and 362 metres asl. The elevation then declines 15 to 25 metres at the East Side Creek, which are values from 330 to 347 metres asl. The long grade to the existing 115 kV Transmission Line to the east brings the elevation of the land at between 370 and 378 metres asl.
3.2.3 Forest Cover, Forest Resources and Vegetation
Mattagami Dam Lake is located within the Missinaibi-Cabonga Section of the Boreal Forest Region (Rowe 1977). The predominant forest cover of the study area is mixedwood, consisting of various associations of mainly Black Spruce, Jack Pine, Balsam Fir, Trembling Aspen and White Birch. White Spruce, Eastern White Cedar, Larch, Red Pine, White Pine, Red Maple, Yellow Birch and Balsam Poplar also occur. The Proposed Undertaking falls within the Romeo Malette Forest (RMF), a Sustainable Forest Licence held by Tembec. The RMF is approximately 628,958 hectares in size and is located between the towns of Gogama, Foleyet, and the City of Timmins (Tembec 2006).
In the RMF, Black Spruce is by far the most important tree species (52.0%), ahead of White Birch (15.6%), Trembling Aspen (13.8%), and Jack Pine (10.6%). Eastern White Cedar, White Spruce, Balsam Fir, Larch, Red and White Pine account all together for only 7.6% of the remaining tree species.
A wildfire known as Gogama No.4 occurred in 1991 (17 years ago) impacting over half of the study area. The site of the Proposed Undertaking, the areas a few hundred to the meters east, and areas to the south remained outside from the forest fire zone. Interestingly, in the fire zone, few fire scars were observed during field work, and furthermore White Birch stump suckering was observed near the existing 115 kV Transmission Line. Therefore, based on the above, it would appear as if most stands in the study area had been harvested prior to the fire.
The past forest history in the study area is illustrated in Figure 2.6 of the Terrestrial Environment Technical Support Document. A part of the study area was site prepared and planted with Jack Pine or Black Spruce Free-to-Grow (FTG) Plantation, while the remainder was naturally regenerated (FTG Natural Regeneration). Today, most stands in the study area are FTGs, and only few are treated and untreated stands with low stocking (Low Stocked Plantation and Low Stocked Natural Regeneration).
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Near or adjacent to the proposed GS, there are two forest stands that were forecasted for harvest in 2008. Ecosites 39 and 48 are immediately west from the proposed GS site (GS site is Ecosite 46); one north and one south from the Kenagamissi Falls Road. These two ecosites are designated as Poplar-Birch-Spruce Mixedwood (Mw3). These two stands represent a total of 2.8 ha. In discussions with Tembec (2010) these stands may be harvested this year.
As illustrated in Figure 2.7 of the Terrestrial Environmental Technical Support Document, the majority of the area is in regeneration with immature and mature forests confined to areas along the Mattagami River and south from the Kenogamissi Falls Road. The mature forests are in fact mature and overmature stands of hardwood and mixedwoods. This correlates with the tree height data which indicates that the disturbed area has tree heights of less than 8 metres for most of the east and north part, while the tree heights for the undisturbed area are between 10 and 20 metres with some localized pockets of Trembling Aspen and White Spruce with heights between 20 and 26 metres. The tree height data was found to be reasonably accurate based on the field work for each stand.
Forest units and non-productive lands are illustrated in Figure 3.2 for the study area. Mixedwoods and hardwoods (Mw1, Mw2, Mw3, Bw1, Po1) are located south of the road, along the existing Transmission Line, and along the Mattagami River. Planted Jack Pine and Black Spruce mixtures (Sp1) and pure or mixed Jack Pine stands (Pj1 and Pj2) are found in the central portion of the study area.
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Figure 3.2 Forest Units and Non-Productive Lands in the Study Area of the Proposed Mattagami Lake Dam GS and Transmission Line Alternatives
A plant list of 115 plant taxa (99 species) identified at the locations to be affected by construction and operation activities of the proposed Mattagami Lake Dam development was developed and is presented in Table 2.3 of the Terrestrial Environment Technical Support Document. Of the 101 species that could be ranked, 96 are designated by the NHIC (2007) as S4, i.e., common and secure, and S5, i.e. very common and demonstrably secure. A total of 14 taxa are identified at the genus level only and thus could not be ranked. The remaining 5 species are SE, i.e., exotic not believed to be a native component of Ontario’s flora. The percentage of exotic species (5.2%) was well below the general proportion of non-native plants in the province, estimated at around 28% (Kaiser 1983).
Undisturbed areas of forest and wetland within the study area have the potential to support plant species which are at risk. Species at risk are species designated with special status under federal and/or provincial legislation.
Federally, species at risk are recognized by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC 2010) and are protected under the Species at Risk Act, whereas provincially they are recognized by the Committee on the Status of Species at Risk in Ontario (COSSARO) under the Ontario Endangered Species Act and the Species at Risk in Ontario List (MNR 2010).
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Species listed in regulation as endangered are afforded protection under the Endangered Species Act.
None of the flora species encountered during the field survey are designated as species at risk by COSEWIC (2010) or COSSARO (MNR 2010). Similarly, based on examination of the MNR Natural Heritage Information Centre (NHIC 2010) and the Species at Risk Act (SARA) Schedule 1 Species at Risk Web Mapping Application (EC CWS 2004) databases, no plant species at risk are located within a 40-km radius from the study area.
A number of terrestrial plant species considered to be significant by MNR were listed in the Mattagami River Watershed Management Plan (Table 2.4). None of these species are considered to be endangered, threatened or of special concern by COSEWIC (2010) or COSSARO (MNR 2010). Based on examination of the NHIC (2010) database, none of the listed species have been recorded within a 40-km radius from the proposed development site.
Wetlands and other environmentally sensitive areas provide important habitat for a variety of plant species and wildlife. Wetlands provide water storage and control functions which reduce erosion and flooding, and improve water quality.
The Ontario Government (1992) issued a Wetlands Policy Statement intended to ensure that there will be no net loss of wetland functions of Provincially Significant Wetlands. The Wetlands Policy Statement was incorporated into the Provincial Policy Statement (OMMAH 2005). A Provincially Significant Wetland is either a Class 1, 2 or 3 wetland situated south and east of the Canadian Shield, or a wetland in another area of the province that the MNR has classified as Provincially Significant through an evaluation of biological, social, hydrological and special features of the area. Development and site alteration are not permitted in Provincially Significant Wetlands in Ecoregions 5E, 6E and 7E (OMMAH 2005). North of Ecoregions 5E, 6E and 7E, development and site alteration are not permitted unless it has been demonstrated that there will be no negative impacts on the natural features or their ecological functions. The Mattagami River system is located north of Ecoregions 5E, 6E and 7E.
Only one small wetland area is present near the proposed Mattagami Dam GS. It is located east between 0.75 and 1.06 km from the proposed GS, along the TL Alternative 2, adjacent and south to the Kenogamissi Falls Road. It is not provincially significant, is classified as “open muskeg” and has characteristics of being a vernal pool. It is identified by code “66” in Figure 3.2, Forest Units and Non-Productive Lands in the Study Area of the Proposed Mattagami Lake Dam GS and Transmission Line Alternatives. It is possible that this wetland was created when Kenogamissi Falls Road was built and the local drainage impacted.
Areas of Natural and Scientific Interest (ANSIs) and Environmentally Sensitive Areas (ESAs) have been identified by the MNR and conservation authorities, respectively, where it has been determined that the natural landscape and/or its features are in need of protection for heritage
Final 3-7 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station appreciation, scientific study or conservation education purposes. There are no ANSIs or ESAs within a 25-km radius of the study area (NHIC 2010).
3.2.4 Wildlife
The two big game species of significance in Northeastern Ontario are moose (Alces americanus) and black bear (Ursus americanus). The MNR has established Wildlife Management Units (WMUs) across Ontario for the purpose of regulating hunting and more effective wildlife and habitat management. WMU 29, the unit which the Mattagami Lake Dam is located, is an area of 8,068 km2.
Moose population estimate in WMU 29 was 2,750 individuals in 1986 and decreased to 2000 in 1993 (Hogg et al. 1995). The moose population estimate value from 1990 to 1995 (5-year average) was 2,242 individuals, which represent a density of 0.28 moose/km2 (McKenney et al. 1998). These values are past estimates and add to our understanding of the moose population in the surrounding of Mattagami Lake Dam.
Black bear are also considered to be common in this area of Northeastern Ontario.
The Proposed Undertaking occurs near the northern extent of the white-tailed deer (Odocoileus virginianus) distribution. The bulk of the white-tailed deer population in Northeastern Ontario is concentrated along the agricultural areas of the Great Clay Belt. With only four small herds, the deer population in MNR Timmins District is small and localized. Of these, one herd is reported to exist within 25 km to the northeast of the Mattagami Lake Dam. Habitat and climatic factors, particularly snow depth, are the major constraints for white-tailed deer.
The numerous rivers and streams in the Timmins area may provide suitable habitat for a number of aquatic mammals such as beaver (Castor canadensis), river otter (Lontra canadensis) and common muskrat (Ondatra zibethicus). Due to the remoteness of the Mattagami Lake Dam GS, wildlife utilization of habitat is expected to occur in the surroundings.
The terrestrial birds in the area of the Proposed Undertaking site tend to be migratory. Very few species reside in the region year-round, and these include grosbeaks, chickadees, woodpeckers, ravens, jays and grouse.
The terrestrial bird species observed in the Timmins area are presented in Table 2.8 of the Terrestrial Environment Technical Support Document. Of the 165 species listed, 107 breed or likely breed in the Timmins area. Of these, 86 are considered by the NHIC (2007) to be S5, i.e. very common in Ontario, demonstrably secure; two are S4S5, i.e. common to very common in Ontario; 12 are S4, i.e. common in Ontario, apparently secure; two are S3S4, i.e. rare to common in Ontario; two are SZN, i.e. no clearly definable occurrences; and three are SE, i.e. exotic, not believed to be a native component of Ontario’s fauna.
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Numerous passerines that are typical boreal species occur in the area of the Proposed Undertaking. In black spruce dominated forests, these include spruce grouse, boreal chickadee, gray jay, yellow-bellied flycatcher, winter wren, Swainson’s thrush, ruby-Crowned kinglet, Nashville warbler, magnolia warbler, yellow-rumped warbler, dark-eyed junco, chipping sparrow and white-throated sparrow (Erskine 1977). In stands dominated by Balsam Fir, the spruce grouse and gray jay are replaced by the ruffed grouse and blue jay, respectively. Jack Pine stands support a less diverse avian community. Birds occurring in Jack Pine communities include American robin, hermit thrush, Swainson’s thrush, ruby-Crowned kinglet, solitary vireo, Tennessee warbler, Nashville warbler, chipping sparrow and white-throated sparrow.
MNR occasionally receives reports of Snapping and Painted turtles in the Timmins and Gogama areas. Both have been observed by MNR staff in the Grassy River watershed, which is a tributary to the Mattagami River (MNR, Personal Communication, 2010). Snapping Turtles are a species of Special Concern under the ESA (2007) but Painted Turtles are "Not at Risk". Neither Snapping Turtles or Painted Turtles were observed during terrestrial or aquatic field investigations at Mattagami Lake Dam. This is not surprising as the proposed site of the GS would not be habitat generally suitable for turtles.
Based on the SARA, ESA and COSEWIC databases a number of wildlife species at risk have ranges overlapping with the study area. However, only the occurrence of the monarch butterfly has been documented to overlap with the local study area and as indicated in the Terrestrial TSD the monarch butterfly prefers open areas with milkweed (Asclepius spp.), which is not present on the development site.
Five avian species have been designated by COSEWIC (2010) and COSSARO (MNR 2010). The loggerhead shrike and red-headed woodpecker are considered to be endangered. The peregrine falcon is considered to be threatened, whereas the red-shouldered hawk and short- eared owl are of special concern. The loggerhead shrike and red-headed woodpecker prefer open woods and open country, respectively. The peregrine falcon, red-shouldered hawk and short-eared owl prefer larger palustrine, riverine and/or lacustrine habitat.
The golden eagle and bald eagle designated as endangered and of special concern under the Endangered Species Act, respectively, have the potential to be present in the general area, particularly in the vicinity of large lakes and rivers (Peck and James 1983, Cadman et al. 1987). The great grey owl, designated as a species of special concern by COSSARO (MNR 2010), may also be present in the general area. COSEWIC (2010) currently considers the golden eagle, bald eagle and great grey owl to be not at risk as species.
Based on the MNR environmental values database, there are no known nesting sites of avian species at risk likely breeding in the Timmins area or within a 25-km radius of the Proposed Undertaking. The loggerhead shrike, peregrine falcon and red-headed woodpecker are considered to be “accidental” in the Timmins area.
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A number of insect species considered to be significant by MNR were listed in the Mattagami River System Watershed Management Plan (Table 2.11). None of these species are considered to be endangered, threatened or of special concern by COSEWIC (2010) or COSSARO (MNR 2010). Based on examination of the NHIC (2010) database, none of these significant species have been recorded within a 25-km radius of the Proposed Undertaking.
3.3 AQUATIC ENVIRONMENT
The proposed hydroelectric power plant development is located on the upper Mattagami River, in the short section of Mattagami River between Mattagami Lake and Kenogamissi Lake at the Mattagami Lake Dam.
The regional setting is generally defined by the Mattagami River watershed (Figure 3.3). The regional setting provides for the baseline description of this watershed and the associated general land and water uses affecting the aquatic environment.
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Figure 3.3 Mattagami River Watershed Generating Stations and Dams
The local study area extends from Mattagami Lake, located immediately upstream of the Mattagami Lake Dam, to Kenogamissi Lake, located approximately 700 metres downstream of the Mattagami Lake Dam (Figure 3.4).
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Figure 3.4 Local Study Area
The baseline setting for the aquatic environment within the regional study area was prepared based on literature review and personal contacts. Environmental baseline conditions have been summarized by Sears (1992) and OPG et al. (2006). This information was augmented and updated by data requested from the MNR, the Ontario Ministry of the Environment (MOE) and Mattagami Region Conservation Authority (MRCA). The baseline aquatic environment information for the local study area was gathered through focused field investigations and discussions with local resource users and MNR personnel.
A detailed description of the field assessment methods is included in the Aquatic Environment Technical Support Document.
3.3.1 Regional Conditions
The Mattagami River is located within the Moose River drainage basin of the Hudson Bay Drainage System (Figure 3.5). The Moose River drainage basin drains approximately 109,000 km2 traversing three physiographic regions: the Canadian Shield, the Great Clay Belt and the Hudson Bay Lowlands (Brousseau and Goodchild l989) (Figure 3.6).
The Mattagami River extends approximately 418 km from its headwaters at Mesomikenda Lake, draining other major tributaries such as the Groundhog River, Grassy River, Kapuskasing River,
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Ivanhoe River, Makami River, Remi River, Opasatika River, Hull Creek and Lost River to its confluence with the Moose River (OPG et al., 2006). The Mattagami River and its tributaries drain approximately 35,612 km2.
Based on historical hydrological data, the greatest streamflow occurs during the spring freshet in April, May and June with the lowest flows occurring generally during the summer near Timmins, and the winter at Smooth Rock Falls (see Table 3.1 of the Aquatic TSD). Extreme maximum and minimum monthly flows near Timmins were 295 cubic metres per second in May 1979 and 17.9 cubic metres per second in September 1991, respectively. Extreme maximum and minimum daily flows at this same location were 539 cubic metres per second on 21 May 1996 and 9.69 cubic metres per second on 14 August 1992, respectively.
Figure 3.5 Moose River Drainage Basin
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Figure 3.6 Major Physiographic Regions of the Moose River Basin
The Mattagami River traverses three physiographic regions: the Canadian Shield, the Great Clay Belt and the Hudson Bay Lowlands (Brousseau and Goodchild 1989).
On the Canadian Shield, the upper Mattagami River has irregular gradients and is typically less than 100 m wide, except where there are in-stream lakes such as Mattagami Lake and Kenogamissi Lake (Seyler 1997). The river channel is tightly contained, with bedrock outcrops
Final 3-14 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station common and manifested as extensive riffle and rapid areas. Inflowing tributaries are generally small.
Due to its good water quality, the Mattagami River is the source of the Timmins potable water supply.
Sediments in the Mattagami River within the Great Clay Belt can be expected to be predominantly silt and clay, particularly in the in-stream lakes and slower moving sections of the river. The Mattagami Lake Dam is situated within the Canadian Shield portion of the Mattagami River, and river substrate has very little silt and clay. Based on the good water quality of the upper Mattagami River and the predominantly coarse substrates in the vicinity of the Mattagami Lake Dam, the substrates can be expected to have low concentrations of contaminants.
Three aquatic plant species considered to be significant by the MNR were listed in the Mattagami River Watershed Management Plan (see Table 3.5, Aquatic TSD). None of these species are considered to be endangered, threatened or of special concern by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC 2006) or the Committee on the Status of Species at Risk in Ontario (COSSARO) (MNR 2006). Examination of the MNR Natural Heritage Information Centre (NHIC 2006) database indicated that there were no records of these three species within a 5-km radius of the proposed development site. Similarly, based on the Species at Risk Act (SARA) Schedule 1 Species at Risk Web Mapping Application (Environment Canada, CWS 2004) database, no aquatic vegetation species at risk have documented occurrences overlapping the local study area of the proposed development site.
Seyler (1997) listed the species that occur in the Mattagami River (Table 3.7 of the Aquatic Technical Support Document). Seyler (1997) indicated that longnose sucker, lake sturgeon, shorthead redhorse, and goldeye do not occur in the vicinity of the Mattagami Lake Dam. Of the species listed in Table 3.7, only lake sturgeon, greater redhorse and goldeye are tracked by the Natural Heritage Information Centre (March 31, 2009). All three are provincially ranked S3 and considered rare to uncommon in Ontario (http://nhic.mnr.gov.on.ca/ nhic_.cfm). However, the record of a greater redhorse in the Mattagami River system is probably incorrect; it is most likely the result of misidentification of shorthead redhorse. Fishes in the genus Moxostoma are notoriously difficult to identify, even for an expert, and confirmed specimens of the greater redhorse are only known from the Ottawa and St. Lawrence River systems, as well as Lakes Ontario, Erie, and Huron (http:// nhic.mnr.gov.on.ca/ nhic_.cfm). Except for lake sturgeon which is listed as “Special Concern”, none of the fish that occur in the Mattagami River are presently considered at-risk federally by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) (http://nhic.mnr.gov.on.ca/nhic_.cfm). Lake sturgeon is also the only fish included in the Species at Risk in Ontario (SARO) list, where it is considered “Special Concern”. Species listed as “Special Concern”, either in the COSEWIC or SARO lists, do not presently have legal protection under the federal Species at Risk Act (SARA) or the provincial Endangered Species Act (ESA 2007), respectively.
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3.3.2 Local Conditions
3.3.2.1 Existing Aquatic Habitat
The results of the habitat surveys conducted on June 21 and December 11, 2006, are illustrated in Figure 3.7, and the results of the habitat survey conducted on September 8 – 11, 2008, is illustrated in Figure 3.8. In the vicinity of the dam, Mattagami Lake slopes down quickly from the shoreline to a depth of approximately 8 m. Mattagami Lake water levels are controlled by the Mattagami Lake Dam, in accordance with the Mattagami River System Water Management Plan (OPG et al, 2006), resulting in a drawdown of lake levels over the winter to provide spring flood protection for Timmins (Appendix A: Compare Photographs 1 and 2; Figure 3.8, Aquatic TSD). Photograph 2 (Appendix A; Figure 3.8, Aquatic TSD) shows the mainly sand substrate of this portion of Mattagami Lake. Immediately upstream of the dam are the remains of an old rock- filled crib structure that extends a short distance from each shore (Appendix A: Photograph 3, Aquatic TSD), and there is an area of rock rubble along the shore at both ends of the dam (Appendix A: Photograph 4, Aquatic TSD). While the crib structure provides some habitat structure in an area dominated by sand substrates, it is unlikely that it provides critical habitat for any fish species residing in Mattagami Lake, due to its configuration, its location within the lake, and the fact that it is exposed to air during the late winter drawdown of Mattagami Lake. Other lake habitats dominated by sand in the vicinity of the control dam, are also unlikely to provide critical habitat for any fish species residing in Mattagami Lake, due to the common nature of the habitat, the fine sand substrate, and the late winter drawdown of the lake.
Between the Mattagami Lake Dam and the road bridge (Figure 3.9: Area A), the Mattagami River is a steep series of rock chutes and rapids, with primarily bedrock substrate (Figures 3.7 and 3.8; Appendix A: Photographs 5, 6 and 7, Aquatic TSD). The bedrock substrate and swift flows limit productivity in this area. Though some fish reside in the deep bedrock pool located half way between the dam and the bridge (Figures 3.10 and 3.8; Appendix A: Photograph 6, Aquatic TSD), it is unlikely that fish can move upstream of the pool, nor is it likely that significant fish reproduction occurs within Area A.
Downstream of the bridge, for a distance of approximately 550 m to Kenogamissi Lake, the Mattagami River is a series of rapids with interspersed reaches of slower, deeper water (Figure 3.10). After passing beneath the bridge (Appendix A: Photograph 7, Aquatic TSD) the river widens and deepens somewhat providing an area of slower water before turning to the east (Figures 3.7 and 3.9: Area B; Appendix A: Photograph 8, Aquatic TSD). This wide area (Appendix A: Photograph 8, Aquatic TSD) has a variety of depths (Figure 3.7), substrates (Figure 3.8), and flow velocities and, based on our observations, is the upstream limit of the walleye and lake whitefish spawning runs. Whitefish during their spawning run were abundant in this pool on November 9 and 10, 2007, and a small number of whitefish eggs were found at the downstream edge of this pool during an intensive search for eggs on December 11, 2006.
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Figure 3.7 Bathymetry and Topography in the Vicinity of the Proposed Generating Station (Global Surveying). The Water Edge on June 21 and on May 2 (Walleye Spawning) was Estimated from Photographs, While the Water Edge on December 11 was Determined by Total Station (Global Surveying)
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Figure 3.8 Substrate Type in the Vicinity of the Proposed Generating Station, Downstream to Kenogamissi Lake. The Water Edge at Four Measured Riverflows was Determined by Total Station (Global Surveying)
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Figure 3.9 Photograph Locations and Watercourse Sections Referenced in this Report
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Figure 3.10 Project Study Area from Mattagami Lake to Kenogamissi Lake, Showing the Main Site Features, the Location and Basic Layout of the Proposed Hydroelectric Station, Watercourse Sections Referenced in this Report, and the Location of Photographs of the Small Watercourse Flowing from the West
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The high bedrock slope along the north side of the river within the upstream end of Area C (Figures 3.10 and 3.8) directs the river to the east. Through the upstream two thirds of Area C the substrate is mostly bedrock in the north half, and mostly boulder and cobble in the south half of the channel (Figures 3.10 and 3.8; Appendix A: Photographs 9 and 10, Aquatic TSD). The boulders and cobble through Area C provide good walleye spawning habitat. In the downstream one third of Area C the bedrock recedes to the north bank of the river, leaving cobble and boulder through most of the channel (Appendix A: Photograph 11, Aquatic TSD).
Area D (Figures 3.10 and 3.9) is a deep pool with slower flow velocity (Appendix A: Photograph 12, Aquatic TSD), that has mostly cobble and boulder substrate with some bedrock along the south side of the river, cobble and gravel along the north side, and sand, gravel and cobble with some bedrock ledges within the deep portion of the pool (Figure 3.8 and Figure 3.10). The maximum depth of this pool is approximately 4 m. Whitefish during their spawning run were abundant in this pool on November 10, 2007, and some were also observed here on September 29, 2009, during their spawning run. Whitefish eggs were found to be most abundant at the downstream edge of this pool, of the locations examined during an intensive search for eggs on December 11, 2006.
Area E (Figures 3.10 and 3.9) is a long rapids that has a high proportion of bedrock and boulders in the east half of the channel, and mainly cobble substrate with a few small boulders on the west side of the channel (Figure 3.8; Appendix A: Photographs 13 and 14, Aquatic TSD). Flow velocity also appears to be somewhat greater in the east side of the Area E channel than in riffle areas along the west side of Area E or in the riffles of Areas C and D. Bedrock and boulders are not suitable substrates for walleye spawning, and combined with the higher water velocities, it is not surprising that walleye are not generally observed spawning in the eastern side of the Area E channel (Figures 3.11, 3.12, 3.13, and 3.14). However, many spawning walleye are usually observed on the west side of the channel in Area E (Figures 3.11, 3.12, 3.13, 3.14), where the slower flow velocities, shallow water, and cobble substrates (Appendix A: Photograph 15, Aquatic TSD) provide good spawning habitat.
In Area F (Figure 3.10), at the transition between lotic and lentic habitats, flow velocity slows and substrates within the east side of the channel appeared to be mainly cobble with coarse gravel and a few boulders (Appendix A: Photographs 16 and 17, Aquatic TSD). Combined with the approximately 1 m water depth in Area F, this location provides good walleye spawning habitat.
A small watercourse drains from the west into Area B, approximately 30 m to the north of the proposed powerhouse location (Figure 3.10). The watercourse is approximately 0.3 - 0.5 m wide with predominantly sand substrate (Appendix A: Photograph 18 - refer to Figure 3.9 for location, Aquatic TSD), and is often incised (Appendix A: Photograph 19 - refer to Figure 3.10 for location, Aquatic TSD). A small culvert conveys it beneath the forest access road in the vicinity of the OPG access lane for the Mattagami Lake Dam, which is perched by 0.2 m at the downstream end (Figure 3.10), effectively blocking any upstream movement of fish beyond this
Final 3-21 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station point. Approximately 200 m of this watercourse was electrofished on August 28, 2007, but no fish were captured. However, it is possible that some small fishes may occasionally or seasonally utilize the lower reaches of this watercourse.
3.3.2.2 Fish Community
The section of the Mattagami River downstream of the Mattagami Lake Dam is known as an important walleye and lake whitefish spawning area for populations of those fishes in Kenogamissi Lake. The Ontario Ministry of Natural Resources (MNR) has monitored walleye spawning at this site and MNR and OPG collaborate to maximize walleye spawning success. MNR alerts OPG to the beginning of the walleye spawning period. The minimum flow implemented for walleye spawning at MLD might vary between 12-15 cms from year to year, depending on the observed and anticipated flow conditions each year, as per the current MRSWMP (2006). To the best of MNR’s knowledge, the flowing water between the Mattagami Lake Dam and Kenogamissi Lake is the only available spawning habitat for the walleye population of Kenogamissi Lake (J. Mucha, Biologist, MNR, Timmins. Personal communication, May 2, 2006). A recreational dipnet fishery is permitted for lake whitefish during that species’ spawning run in the fall.
Electrofishing on June 21, 2006, downstream of the bridge in Area B and in the upstream end of Area C (Figure 3.10) for a total of 742 electroseconds (duration that the electrofishing unit was emitting an electrical charge to the water), captured 2 longnose dace, 1 yellow perch, 1 burbot, and 1 logperch. This same area was electrofished again on August 28, 2007, for a total of 1,295 seconds, capturing 12 yellow perch, 4 smallmouth bass, 40 logperch, 12 longnose dace, 2 mottled sculpin, 1 mimic shiner (Notropis volucellus), and 1 lake chub. Also on August 28, 2007, the small watercourse draining from the west into Area B was electrofished (Figure 3.10), but no fish were captured. During an intensive search for lake whitefish eggs on December 11, 2006, many burbot, longnose dace, and logperch, as well as 1 yellow perch, were observed in the shallow water.
3.3.2.3 Walleye Spawning
Background Walleye typically spawn in the spring at water temperatures of 5.6 to 11.1°C over boulder to coarse gravel (Scott and Crossman, 1973), generally in water less than 1.2 metres deep (Smith, 1985), and in velocities from 0.3-1.0 metres per second (McMahon et al, 1984). Spawning grounds are often the rocky areas below impassable falls and dams in rivers, or boulder to coarse gravel shoals of lakes (Scott and Crossman, 1973).
Observations On May 2, 2006, the water temperature downstream of the Mattagami Lake Dam was 9.9°C in the early afternoon. By May 3 at 3:40 pm, the water temperature had risen to 12.3°C. On the
Final 3-22 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station evening of May 2, after nightfall, approximately 100 spawning walleye were observed at various locations within Areas B and C (Figure 3.11).
The water temperature downstream of the Mattagami Lake Dam was 7.7°C at 6:00 pm on May 2, 2007. Later that evening, after nightfall, approximately 328 walleye were observed in a number of locations throughout Areas B, C, D, E and F, wherever habitat was suitable for spawning (Figure 3.11).
River flow was higher than usual during the spring melt of 2008, with values of approximately 150 m3/s at the start of the walleye spawning period. MNR determined that OPG should consider the spawning run to be underway on May 8, 2008. Consequently, OPG reduced the flow from the Mattagami Lake Dam to approximately 15 m3/s on the morning on May 8. On May 8, 2008, the water temperature downstream of the Mattagami Lake Dam was 8.2°C in the early evening. By the evening of May 9, 2008, the water temperature had risen to 8.5°C. No walleye were observed in Areas B and C on May 8, 2008, but six walleye were observed widely scattered throughout these two areas on May 9 (Figure 3.12). One walleye was observed in Area D on May 9, 2008. Though Area E provides an extensive area of walleye spawning habitat along the west side of the river where about 150 walleye were observed in 2007, in 2008 only twenty walleye were observed here on May 8, and again on May 9 (Figure 3.12). Area F is where the river habitat transitions to lake habitat, and provides a relatively large area of walleye spawning habitat. Twenty-seven walleye were observed in Area F on May 8, and twelve were observed here on May 9, 2008 (Figure 3.12), which contrasts with the 84 walleye observed here in 2007. It is speculated that the cooler than average spring in 2008 may have delayed the walleye spawning by a few days. This, combined with the higher than usual river flow leading up to the start of walleye spawning, may have resulted in less favourable spawning habitat conditions in the river. It is likely that in 2008 much of the walleye spawning occurred within Area F or slightly downstream in Kenogamissi Lake.
In 2009, the water temperature downstream of the Mattagami Lake Dam was 7.3°C in the early evening on May 11, and approximately 290 walleye on their spawning run were observed after nightfall in Areas B, C, D, E and F (Figure 3.13). By the evening of May 12, 2009, the water temperature had risen to 8.9°C, and after nightfall that evening approximately 239 walleye were observed (Figure 3.13).
In 2010, the water temperature downstream of the Mattagami Lake Dam was 7.3°C in the early evening on April 19, and approximately 135 walleye on their spawning run were observed after nightfall (Figure 3.13). On the evening of April 20, 2010, the water temperature was still 7.3°C, and after nightfall that evening approximately 162 walleye were observed (Figure 3.14). Riverflow was low in 2010, due to an exceptionally dry and warm spring, necessitating MNR and OPG agreeing to discharge only 5-6 cubic metres per second during the walleye spawning and incubation period (Louis Verville, OPG. Personal Communication, June 25, 2010), rather than the minimum of 12 – 15 cubic metres per second specified in the Mattagami River Water Management Plan (OPG et al., 2006).
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At the time of the 2006, 2007, 2008 and 2009 spawning observations, the flow released from the Mattagami Lake Control Dam was approximately 12-15 cubic metres per second, based on OPG records. The observed pattern of spawning locations within this portion of the Mattagami River is a function of the river morphology and its effect upon depth, water velocity, and substrate type. In this portion of the Mattagami River, the streambed at the outside of the bends (where water velocities are higher) is composed mainly of bedrock and larger boulders, and the streambed at the inside of the bends (where water velocities are lower) is composed mainly of cobble material. This is illustrated in Photographs 9, 10, 13 and 15 (Appendix A, Aquatic TSD). During the walleye spawning period in spring, river flow is such that the water velocity is too high for walleye spawning along the outside of the bends, but is suitable for spawning along the inside of the bends. This pattern of velocity and substrate results in the best spawning habitats being located in the inside of the bends, as illustrated by the observations of spawning fish (Figures 3.11, 3.12, 3.13 and 3.14). Exceptions to this general location pattern were observed at the downstream end of the two pools (Areas B and D) where the deeper water in the pools slowed velocity enough to provide some localized spawning habitat on the outside of the bend. The numbers of spawning walleye, as well as the pattern of spawning locations, were not appreciably different in 2010, despite the lower than usual flow of 5 cubic metres per second released from the Mattagami Lake Control Dam (compare Figure 3.14 with Figures 3.11 and 3.3). The primary impact of lower flows in 2010 upon the walleye spawning run, was to the broad and shallow spawning habitat along the west side of Area E, where a reduction in the available spawning area is reflected in the lower numbers of spawning fish observed. The lower than usual flows in 2010 appeared to have little impact upon other walleye spawning locations within the study area.
Most of Area A (Figure 3.11), between the dam and the road bridge is very steep and, thus, is inaccessible to walleye, and the bedrock substrate there does not provide spawning habitat (Figure 3.8; Appendix A: Photographs 5 and 6, Aquatic TSD). No walleye have ever been observed in the portion of Area A, immediately upstream from the road bridge, where walleye access may be possible and substrate is not entirely bedrock (Figure 3.8; Appendix A: Photograph 7, Aquatic TSD), during the spawning observations conducted in 2006, 2007, 2008, 2009 and 2010.
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Figure 3.11 River Reaches Examined and Number of Walleye Observed During the 2006 and 2007 Walleye Spawning Investigations. The Numbers Represent the Number of Walleye Observed in the Adjacent Area Outlined in Yellow, and Pertain to 2007 Unless Otherwise Indicated
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Figure 3.12 River Reaches Examined and Number of Walleye Observed During the 2008 Walleye Spawning Investigations. The Number of Walleye Observed on May 8/9, 2008, is Indicated for those Areas where Fish were Found
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Figure 3.13 River Reaches Examined and Number of Walleye Observed During the 2009 Walleye Spawning Investigations. The Number of Walleye Observed on May 11/12, 2009, is Indicated for those Areas where Fish were Found
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Figure 3.14 River Reaches Examined and Number of Walleye Observed During the 2010 Walleye Spawning Investigations. The Number of Walleye Observed on April 19/April 20, 2010, is Indicated for those Areas where Fish were Found
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3.3.2.4 Lake Whitefish Spawning
Background Lake whitefish in Canada typically spawn from late September to December, at temperatures less than 7.8°C (Scott and Crossman 1973). Scott and Crossman (1973) and Coad et al. (1995) report that spawning usually occurs in water less than 7.8 metres deep, while Becker (1983) gives a range from 2 to 18 metres. Substrate type varies widely, and some populations spawn in rivers, while others spawn in lakes (Becker, 1983; Coad et al., 1995; Scott and Crossman, 1973). Becker (1983) and Coad et al. (1995) state that female whitefish rise to the surface while emitting spawn, accompanied by one or two males discharging milt. The broadcast eggs settle to the bottom and receive no parental care (Becker 1983; Coad et al., 1995). The eggs are 2.95 ± 0.01 millimetres in diameter, and hatch during the early spring (Becker, 1983).
On October 18, 2006, two dipnetters were fishing downstream of the road bridge on the west side of the river (Appendix A: Photograph 20, Aquatic TSD). On this day, they had not captured any fish, but they had captured a couple of fish a few days earlier. A discussion with the dipnetters revealed that they have fished this location every year for approximately the past twenty years. They stated that fishing begins around the middle of October and continues, sometimes, into December. They, as well as others, fish in two locations where the water is slower and deeper than most places downstream of the bridge (Figure 3.9: Area B and Area D; Appendix A: Photographs 8 and 12, Aquatic TSD). They did not think that whitefish migrate farther upstream than the bridge. Of the two fishing locations, the farther downstream location is best, but it is more difficult to access, which is why they usually stay near the bridge. Subsequent telephone conversations with one of the dipnetters on November 1, 14 and 19, 2006, revealed that they only captured a few fish over the entire fishing period in 2006, and that they only captured a few fish in 2005 also. Previous years had higher catches, with daily catches of up to 75 fish possible during some years.
On November 9, 2007, two dipnetters, different than those observed in 2006, were fishing at the lower whitefish spawning pool (Figure 3.15: Area D). They had only captured one fish thus far that day, but stated that 2007 had been a very good year for fishing and the fishers were capturing 15 - 25 fish per person per visit. While we were on-site, the fishers moved to the upper whitefish spawning pool (Figure 3.15: Area B) and captured six whitefish within about 15 minutes. They stated that the lower pool (Area D) was generally a better place to catch fish than the upper pool (Area B), but it could vary from day to day. The six fish captured appeared to be at the end of their spawning run, and the fishers remarked that likely only a few days of worthwhile fishing remained.
The fishers were contacted after the close of the 2008 lake whitefish season, and they reported that fishing had been very poor from the start of spawning in late October to almost the end of November. Near the end of November, the weather became unseasonably warm, and then
Final 3-29 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station fishing suddenly improved for a few days before ending for the year at the end of November. They also noticed an unusually low number of eggs in the fish.
In 2009, the group of local fishers that have been contacted every year since 2006 could not be contacted. However, contact was made with another fisher on November 2, 2009, first contacted in 2008, who assists his father who holds the commercial whitefish netting licence on Kenogamissi Lake. He stated that he caught very few fish in his father’s gill nets that are set in Kenogamissi Lake near the mouth of the Mattagami River. He also stated that the dipnet fishers that operate in the two pools of the Mattagami River, downstream of the road bridge (Figure 3.16), had caught very few fish in total. C. Portt and Associates staff (G. Coker, J. Reid) also examined the area around these two pools on October 29, 2009, and found no evidence of fish cleaning, though there were four recent wooden tripod structures that are part of the dipnetting equipment.
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Figure 3.15 Lake Whitefish Spawning Locations Between the Mattagami Lake Dam and Kenogamissi Lake. The Areas Examined for Whitefish Eggs in 2006, and the Sections of River Examined for Spawning Whitefish with an Underwater Video in 2007 and 2008, are Shown
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Figure 3.16 Lake Whitefish Spawning Locations between the Mattagami Lake Dam and Kenogamissi Lake. The Areas Examined for Spawning Whitefish with an Underwater Video in 2009 are Delineated in White, and the Area where Lake Whitefish were Observed is Denoted by White Hatching
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Observations Observations were made in 2006 for spawning whitefish throughout Areas B, C and D, as well as a short distance upstream of the bridge into Area A, on October 17 (day only), October 18 (day and night), November 20 (4:00 - 5:55 pm), and December 11 (day only). On October 17 and 18, 2006, the water temperature downstream of the Mattagami Lake Dam was 8.3°C, and on November 20, 2006, it was 2.0°C. The December 11 observations occurred during a short- term (approximately 4 hours) flow reduction, so instream visibility was excellent. No whitefish were observed on any of these occasions.
Fish eggs, presumed to be whitefish eggs based on size, colour, and the fact that whitefish are the only known fall spawner present, were collected during the planned flow reduction on December 11, 2006. Along the west side of Area B (Figure 3.15), 1 live (clear) egg was collected in 30 collection attempts. Along the east side and the downstream edge of Area B, 1 dead (opaque) egg was collected in 13 collection attempts. Along the downstream edge of Area D, 4 live eggs and 1 dead egg were collected in 6 collection attempts. All eggs collected in Area D were collected in the 2 deepest and farthest offshore collection attempts, and where subsequent removal of rocks revealed additional eggs that could be observed.
Whitefish spawning observations in 2007 were conducted in Areas B, C, D, the upstream end of Area E, and in Area F, on November 9 and 10, using an underwater video camera attached to a buoy (Figure 3.15). Whitefish were only observed in the deep water of the two pools or in the shallow faster flowing water at the downstream end of the pools (Figure 3.15: Areas B and D). The same locations, except for Area F, were examined on November 21, 2008, when the water temperature was 2.7°C, but no fish were observed.
Whitefish spawning observations in 2009 were conducted in Areas B, C, D, the upstream end of Area E on October 29, also using an underwater video camera attached to a buoy, however, the more turbulent and shallow rapids were not examined out of concern that the video camera would not survive (Figure 3.16). Whitefish were only observed in deep water within the upstream end of the pool in Area D (Figure 3.16).
3.3.3 Summary of Existing Conditions
The fish community in the vicinity of the proposed GS reflects the relatively simple community structure that is typical of many of the rivers in the Hudson Bay drainage, as well as the mainly shallow riffle habitat, with occasional deeper areas, that is present in this section of Mattagami River. The small fishes captured here are typical for this location and habitat. Logperch and longnose dace are common species inhabiting riffle habitat in riverine situations. Yellow perch are more common in Kenogamissi Lake, but some likely inhabit the slower flowing habitats that occur in Areas B and D. Though usually found in the deeper waters of lakes and larger rivers as adults in summer, young burbot are often found along rocky shores (Scott and Crossman, 1973), and, when present, are often electrofished from the interstitial spaces of cobble or rip-rap in rivers or larger streams (G. Coker, personal observation). Walleye and lake whitefish are
Final 3-33 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station also part of the fish community during their respective spawning runs and during the incubation and hatching period as embryos and fry.
The Mattagami River, from downstream of the road bridge to Kenogamissi Lake, is an important spawning area for the walleye population of Kenogamissi Lake. Our observations within Area B, with regard to the habitat utilized by spawning walleye, are consistent with observations undertaken by MNR (J. Mucha, Biologist, MNR, Timmins. Personal communication, November 21, 2006). During the 2007 walleye spawning season, when the entire length of river between the Mattagami Lake Dam and Kenogamissi Lake was examined, walleye were observed nearly everywhere that suitable substrate and velocities occurred downstream of the bridge in Areas B to F (Figures 3.11 to 3.14).
The Mattagami River, downstream of the road bridge to Kenogamissi Lake, apparently contains at least two spawning areas for the lake whitefish population of Kenogamissi Lake. Discussions with the whitefish dipnetters, as well as the results of the egg collections undertaken on December 11, 2006, and underwater video observations of lake whitefish during their 2007 and 2009 spawning run, suggest that the spawning habitat in Area D is utilized more than that in Area B (Figures 3.15 and 3.16). This may be the case because Area D has a larger area of deep water and a greater maximum depth than Area B, as well as slower flow velocities. These characteristics may make Area D better whitefish spawning habitat than Area B, based on the descriptions of spawning habitat and behaviour in Scott and Crossman (1973), Coad et al (1995) and Becker (1983). Given that lake whitefish prefer deeper water for spawning than what is generally found throughout this section of river, and that they also will readily spawn in lakes, it is possible that this section of river is not the only spawning area for the Kenogamissi Lake population.
3.4 AIR/NOISE
Mattagami Lake Dam is located in a remote wilderness area with no other permanent use except for the noise of traffic along Highway 144 and Kenogamissi Falls Dam Road. No other human noises are generally present in the area and local air quality is good. The most significant source of noise is the sound of water being spilled at the Falls.
The existing air quality was not assessed as part of the project, as hydroelectric generating stations do not produce air emissions.
3.5 SOCIO-ECONOMIC ENVIRONMENT
For the purposes of the socio-economic assessment, the analysis has been broken down into two study areas: regional and local.
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The regional study environment has been defined as the City of Timmins to the north and the community of Gogama to the south. The regional study environment also includes the Mattagami First Nation Reserve 71.
The local study area for the socio-economic discipline is defined as the area encompassing the proposed undertaking and an adjacent buffer of 1 km. This includes the proposed transmission corridor and the site of the proposed GS including the area for the penstock, the existing dam and OPG access roads.
3.5.1 Demographics, Community and Economy
Northeastern Ontario is a resource based economy driven primarily by the forest products and mining sectors. Tourism which is largely resource-based (e.g., fishing, hunting, other outdoor recreation) is a minor contributor as compared to the industrial resource base, but nevertheless is an important contributor to the economy. Government services whether it be federal, provincial or local are also a major contributor to the economy and employment of people. Most of the other sectors of the northern Ontario economy such as retail and wholesale trade, other manufacturing, construction and services are generally dependent on and strongly impacted by the economic cycles within the resource industries.
Timmins is the major economic centre for a vast section of Northeastern Ontario stretching from Hearst in the west to James Bay in the North, the Quebec border in the east to the northern section of Timiskaming District in the south (Sudbury and North Bay become the major centres further south). Timmins is the centre for industry, commerce, distribution and finance for communities in this region such as: Cochrane, Smooth Rock Falls, Kapuskasing, Hearst, Chapleau, Iroquois Falls as well as many other smaller communities serving a regional market territory of approximately 118,000 people (City of Timmins, 2006). Timmins is also a major gold mining centre.
Gogama is an unorganized community located about 110 km south of Timmins and 185 km north of Sudbury. The main employer in the Gogama area is Gogama Forest Products, softwood sawmill partly owned by EACOM. The mill employs approximately 75 individuals. Logging operations are also an important employer in the area with local individuals harvesting on the Pineland, Spanish and Timiskaming (Shining Tree Area) Forests.
Tourism is also an important sector in Gogama, which boasts several hunting/fishing lodges and outposts. The wilderness surrounding Gogama is covered with hundreds of pristine lakes and rivers harbouring various fish species such as, walleye, pike, bass, perch, whitefish, muskellunge, trout, carp and sucker. Access to many of these water bodies is possible by water or roads, some of which require 4-wheeled drive vehicles. Other lakes are only accessible by air and can be reached using the services of local outfitters who offer “fly-in” packages.
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Timmins has an estimated population of 42,997 in 2006, a decrease of 1.6 percent from the 2001 population of 43,685, the median age of 39.6 compared to 39.0 for Ontario and 39.5 for Canada.3 Twenty-seven percent of the population falls between the ages of 25-44 indicating a large available workforce.
The population of Gogama is estimated to be roughly 500 to 600 people, with the population increasing during summer.4
Mattagami First Nation is a small First Nation with a total population of 416 and an on-reserve population of 154. Band members are employed in local band administration, logging operations, a community development corporation, the local school and a gas bar/restaurant/variety store along with other occupations. Mattagami First Nation is located about 100 kilometres south of Timmins and about 15 kilometres from Gogama.
There are approximately 79 homes on the Mattagami FN reserve as well as a band office, church, variety store, fire hall, school, youth recreation center, Binoogesh Center and storage buildings (MNR, 2005).
3.5.2 Land and Resource Use, Access and Transportation
The Proposed Undertaking is located in an area that is predominantly Crown land. The proposed GS would be located on the northern edge of a General Use Area of Crown land known as: “G1813 Predominant Cottaging Area” for Timmins and Kirkland Lake MNR District. Commercial power generation development is one of several permitted use activities within this general use area. The primary recreational use in these areas is a combination of public recreation, commercial tourism and cottaging. Other permitted commercial activities include aggregate extraction, bait fish operations, commercial fishing, trapping, forestry, mineral exploration and development, peat extraction and wild rice harvesting. The land use direction for this area is from the Crown Land Use Policy Atlas (Ministry of Natural Resources, 2006).
Slightly north of the Proposed Undertaking is the G1826: Kenogamissi-Mattagami Recreational Corridor. This is a General Use Area that consists of 120 metres on each side of the southern section of the Mattagami River. Commercial power generation development is also permitted in this land use area; however, the primary use is for public recreation, cottaging and tourism (Ministry of Natural Resources, 2006b).
The proposed transmission line corridor will be located in both the “G1813 Predominant Cottaging Area” and the extreme northern end of the “G1809 Gogama Resource Area”. This land use area also permits commercial power generation development and the existing Hydro One Transmission Line from Timmins to Sudbury is located in this area. The primary activities
3 Unless otherwise identified, all the social data presented in this report is based on 2006 Statistics Canada census information. 4 Gogama is not a separate municipality and therefore Statistics Canada does not tally the population by census subdivision.
Final 3-36 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station in this area are sustained yield timber production and mineral exploration and development (Ministry of Natural Resources, 2006c).
It is important to note that sections 1.8.2 and 1.8.3 of the Provincial Policy Statement encourage increased energy supply from waterpower resources:
“Increased energy supply should be promoted by providing opportunities for energy generation facilities to accommodate current and projected needs, and the use of renewable energy systems5 and alternative energy systems, where feasible.”
“Alternative energy systems and renewable energy systems shall be permitted in settlement areas, rural area and prime agricultural areas in accordance with provincial and federal requirements. In rural areas and prime agricultural areas, these systems should be designed and constructed to minimize impacts on agricultural operations.”
OPG currently has a Licence of Occupation for Mattagami Lake Dam that allows OPG to overflow and flood certain adjacent lands by reason of the existing storage at Mattagami Lake Dam.
The area around the Proposed Undertaking is wholly contained with the Romeo Malette Forest, a Sustainable Forest Licence issued to Tembec, which operated a softwood sawmill in Timmins, which has been idled since 2007. The Licence stipulates that most of the conifer resource is directed to Tembec mills and most of the hardwood is directed to Grant Forest Products (now Georgia-Pacific). A Forest Management Plan for the Romeo Malette Forest is prepared on a five year term.
Access to the Proposed Undertaking is via Kenogamissi Dam Road about 2 kilometres west of Highway 144. The MNR has delegated responsibilities for the Kenogamissi Falls Road and the bridge the crosses the Mattagami River to Tembec. Tembec is required to maintain the road and bridge in good repair or rehabilitate the road and the bridge site should they be no longer required. A Use Management Strategy for the Kenogamissi Falls primary road is included in the 2007-09 Contingency Forest Management Plan (FMP) which assigns responsibility to Tembec. Tembec has also signed a Memorandum of Agreement with the MNR regarding the standards and use for the Kenogamissi Falls Bridge.
This road is utilized by resource users in this area primarily anglers, hunters and trappers. One prospector also uses the road. The use of this area by outfitters and Bear Management Area (BMA) operators is unknown. Hydro One may also occasionally use this road to conduct maintenance on its 115 kV transmission line that runs from Timmins to Sudbury.
5 Renewable energy systems means the production of electrical power from an energy source that is renewed by natural processes including, but not limited to, wind, water, a biomass resource or product, or solar and geothermal energy.
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The volume of daily or weekly traffic on Kenogamissi Falls Road is extremely light in particular if Tembec is not undertaking any harvesting and log hauling operations in the area. Other than forest industry operations, vehicular traffic is largely restricted to the occasional outdoor recreation enthusiast (e.g., hunter, angler, and trapper).
OPG staff periodically visit the existing Mattagami Lake Dam facility to operate and conduct maintenance works at the existing control dam.
There are no mineral claims at either the site of the Proposed Undertaking GS. One mineral claim, #4217582 occurs east of the Hydro One 115 kV line and which requires access via Kenogamissi Dam Road. MNDMF has withdrawn the lands associated with the proposed GS from the staking of mineral claims and activities.
A small cottaging area is located to the south of the Proposed Undertaking on Mattagami Lake. In comparison to Southern or Central Ontario, this is a sparsely concentrated cottaging area with approximately two cottages located within one kilometre of the proposed GS. A larger cluster of approximately 30 cottages is located within five kilometres to the south of the proposed GS on Kenogamissi Lake. Some of these cottages are water access only.
There are no cottages to the north of the proposed GS on Mattagami Lake within one kilometre and there are two within five kilometres on Kenogamissi Lake.
The area around the proposed tailrace is a known fishing area. The key species in which the anglers target are whitefish and walleye. In particular, the site of the proposed powerhouse immediately north of the existing bridge and south end of Kenogamissi Falls is utilized by recreational anglers. The consultant team noted that in 2007 out of total of 15 days at the site, anglers (May – November) were noted on two occasions (party of 2 both times) or 13% of the time. It should be noted that these were all weekdays and weekend observations were not included.
Rather uniquely, there are a small number of individuals who use dipnets to catch whitefish in the autumn. It also appears that there may be the odd tourist outfitter who takes guests to this location for dipnetting and angling (Ballak 2007).
Kenogamissi Lake has had a commercial whitefish fishery in the past.
Recreational canoe trips on the upper Mattagami River are reported to occur on a very infrequent basis. Discussions with OPG operational staff and Mattagami First Nation representatives indicate that a couple of parties are reported annually on the river.
The presence of Kenogamissi Falls and the Mattagami Lake Dam necessitates a portage on the western side of the river. The portage begins in the cleared area just upstream of the boom line and follows the existing OPG access road to the site. At Kenogamissi Falls Road the portage
Final 3-38 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station cuts around a high rocky hill that occurs on the north side of the proposed generating station site. This portage also doubles as a boat launch for the south end of Kenogamissi Lake. This portage is estimated to be 1,200 metres in length.
Hunting in this area of Northern Ontario is typically for moose, bear and small game (e.g., grouse, partridge). Moose hunting is the most popular activity undertaken by both residents and non-residents. Bear hunting is typically undertaken by non-residents of Ontario. Small game hunting is undertaken by both residents and non-residents.
A bear stand was observed within 100 metres of the proposed transmission corridor about 1km east of Kenogamissi Falls and 50 metres north of Kenogamissi Falls Road. Bear stands are not recognized values within MNR’s Natural Resource Values Information System.
Crown land camping is allowed throughout Northern Ontario, although non-residents do require a permit. No camping currently exists at or near the proposed GS or transmission line and no camping was observed by OPG staff or the EA consulting team. For safety reasons, Crown land camping is discouraged at the existing Mattagami Lake Dam site via signage and fencing placed by OPG. OPG understands through conversations with MNR that camping may occur midway and at the northern terminus of the portage.
Trapping is a common traditional activity in Northern Ontario undertaken by both Aboriginal and non-Aboriginal peoples. Today, trapping is perhaps more important as a social, cultural and personal activity than it is as an economic one. Typical furbearer species targeted by trappers on the Romeo Malette Forest includes marten, beaver, mink, muskrat, fox, lynx, fisher, weasel, red squirrel and otter (Tembec, 2007).
The following traplines are situated in the local study area or use of the trapline impact by any road construction: TI015, TI003, TI008, GO005, GO004, GO009, GO015 and GO016. Of these traplines, GO 004, GO 005, GO 0009 (largely covering Beemer, Moher, Gouin, Emerald and Nursey Townships) belong to Mattagami First Nation members and GO 015 is a Mattagami First Nation community trapline.
3.6 CULTURAL HERITAGE STUDIES
Dr. John Pollock of Woodland Heritage Services Limited, in conjunction with Chris McKay6 a subcontractor of SENES and a member of Mattagami First Nations, conducted the archaeological and cultural heritage assessments for the Proposed Undertaking at Mattagami Lake. A ground based cultural heritage assessment was carried out at the site of the Proposed Undertaking including the preferred transmission corridor. This work was undertaken according to Ontario Heritage Act Regulations which involved field visits by a licensed archaeologist. The Cultural Heritage assessments have been conducted in accordance with the Ontario Heritage Act and the guidelines recommended by the Ministry of Tourism and Culture.
6 Chris is a member of Mattagami First Nation and the manager of the First Nation’s values dataset.
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Previous archaeological work in the area indicates that the general Mattagami River watershed north of Timmins was occupied by Native Peoples for a minimum of 6,000 to 7,000 years. The earliest people, whom archaeologists refer to as the Shield Archaic Tradition, were big game hunters who lived in the area following the last glacial ice-age. About 2,000 years ago, these people shifted to an economy of smaller game and fishing which required smaller tools and a seasonal round to exploit various resources at different times of the year. Fired clay pottery was added to the material culture at this time by the people who were called the Laurel Tradition or Middle Woodland Culture. The Laurel Culture gradually evolved into the late Woodland Blackduck (Ojibway) and Selkirk (Cree) pottery styles. These people were the ancestors of present day regional cultural/social groups such as the Mattagami First Nation (Settlement Surveys Ltd. 1995).
3.7 FIRST NATIONS & ABORIGINAL PEOPLES
3.7.1 Context
A number of First Nations participated in the Mattagami River System Water Management Plan (MRSWMP) exercise between 2002 and 2004: Mattagami, Matachewan, Wahgoshig, Brunswick House, Chapleau Ojibwe, Taykwa Tagamou, Beaverhouse Aboriginal Community (not recognized by Indian and Northern Affairs Canada (INAC) as a First Nation) and Missinaibie Cree. Métis people are also scattered throughout Northeastern Ontario and local Métis individuals are represented by the Métis Nation of Ontario Timmins Council.
Of the various First Nations that participated in MRSWMP, OPG and MFN identified that the Proposed Undertaking might be of interest to other Wabun Tribal Council First Nation members, particularly Matachewan, Wahgoshig and Flying Post First Nations.
More information on the consultation program with First Nations and Aboriginal Peoples is summarized in Chapter 6 and is also provided in the First Nations and Aboriginal Peoples Consultation Technical Support Document for this Environmental Report.
3.7.2 Mattagami First Nation
The Mattagami FN Reserve located near Gogama is approximately 40 km south of the Wawaitin GS and has a historical interest in hydro development on the river owing to the flooding of Mattagami Lake that affected their traditional and existing Reserve lands. The impact caused by the flooding has been addressed by OPG through a past grievance process.
Mattagami First Nation approached OPG in 2005 about collaborating on the development of a hydroelectric facility at Mattagami Lake Dam. As such, OPG has moved forward with the project, considering MFN as a partner in it. The Mattagami Lake Dam is located near MFN’s Reserve and is in the centre of their traditional territory.
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Mattagami FN is a small First Nation with a total population of 416 and an on-reserve population of 154. Band members are employed in local band administration, logging operations, a community development corporation, the local school and a gas bar/restaurant/variety store along with other occupations. Mattagami FN is located about 100 km south of Timmins and about 20 km from Gogama. There are approximately 67 homes on the Mattagami FN reserve as well as a band office, church, variety store, fire hall, school, youth recreation centre, Binoogesh Center and storage buildings (OPG, et al. 2006). Many band members continue to pursue traditional resource activities such as trapping, hunting, fishing and gathering.
3.7.3 Matachewan First Nation
The Matachewan FN Reserve is located near the unincorporated municipality of Matachewan in Temiskaming District. The Matachewan FN has a total population of 556 individuals of which 40 are on Reserve. Historically, the Matachewan FN has a traditional area along the upper Montreal River system; however, an offer to consult was made to the Matachewan FN as well. Many members continue to pursue traditional resource activities such as trapping, hunting, fishing and gathering.
3.7.4 Flying Post First Nation
The Flying Post FN is located in Nipigon, Ontario and has a total population of 162. The Flying Post FN has an uninhabited Reserve approximately 80 km from Mattagami Lake Dam.
3.7.5 Wahgoshig First Nation
Wahgoshig First Nation is located approximately 160 kilometres from the Mattagami Lake Dam east of Matheson and near the Quebec border.
3.7.6 Métis
Métis peoples in the Timmins area are represented by the Métis Nation of Ontario Timmins Council. The Council has a diversity of interests including lands, resources and the environment.
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4.0 PREDICTED ENVIRONMENTAL EFFECTS AND PROPOSED MITIGATION MEASURES DURING CONSTRUCTION AND OPERATIONS
4.1 POTENTIAL SOURCES OF EFFECTS
This chapter describes the environmental effects expected as a result of the Proposed Undertaking. The chapter first highlights the potential source of the effect and then more fully describes the predicted effects attributed to the Proposed Undertaking.
4.2 TERRESTRIAL ENVIRONMENT
The available environmental baseline information and site-specific studies provided the basis for an assessment of potential construction and operational effects on the terrestrial environment, e.g., due to vegetation clearing, soil erosion, noise, blasting, increased human activity, etc. Recommended mitigative measures for project effects on the terrestrial environment are based on standard environmental construction guidelines, relevant government guidelines for proposed hydroelectric power plant development, as well as government agency and other organization consultation. The significance of potential impacts was based on their magnitude, duration and extent after the implementation of recommended mitigative measures.
4.2.1 Geology, Soils and Acid Rock Drainage
The Proposed Undertaking is planned to be constructed on the western shore of the river downstream from the bridge. Considering the outcrop observed on the shoreline, from the existing Mattagami Lake Dam to the bridge downstream, the location where the powerhouse and its tailrace will be located will have to be excavated. Therefore, blasting may be required to make possible the construction of the powerhouse, the tailrace, penstocks and any other ancillary infrastructures. For the proposed GS no effects on geology are anticipated beyond the powerhouse and tailrace footprints, and any ancillary infrastructure requiring blasting for construction.
If explosives will used in construction they will be closely controlled, with their use restricted to authorized personnel who have been trained in the use of explosives in a manner so as to minimize impacts on the environment. Appropriate government agencies will be informed of the blasting schedule in advance of construction, as well as just prior to the detonation program. All necessary permits will be obtained by the Contractor hired by OPG, who will also comply with all legal requirements in connection with the use, storage and transportation of explosives, including, but not limited to, the Canada Explosives Act and the Transportation of Dangerous Goods Act. The Contractor will be required to retain a consulting engineer with technical expertise in blasting to provide advice on maximum loading of explosives for all blasting, as well as an engineering report indicating recommended charges and blasting methods to be used at
Final 4-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station specific locations. All blasting will occur in such a way as to be in compliance with federal regulations and directions. All blasting will follow the DFO Blasting Guidelines.
The available information for the assessment of acid rock drainage potential consisted of nine Acid Base Accounting (ABA) analyses of drill core, two of which are splits of a pulp, and two appear to be separate splits of the same drill core interval. The geotechnical report notes that bedrock in the area tested is granite with felsic and dioritic dikes. This type of rock typically has a low potential for Acid Rock Drainage (ARD) however granite can contain sulphide minerals and have the potential to generate ARD in some areas, and therefore additional analysis in the form of Acid Base Accounting (ABA) testing is useful and this testing was conducted.
The ABA results confirmed that the granite tested does have a very low sulphide content. The highest sulphide sulphur level in these samples is 0.02%, which is a negligible amount. The BC ML (Metal Leaching)/ARD Guidelines (1997) suggest that below 0.3% sulphide sulphur, there should be no concern with respect to metal leaching/acid rock drainage (ML/ARD), unless the material has elevated metal levels and/or the levels of neutralizing potential (NP) are relatively low. It should be noted that the guidelines are being revised and this cut-off will be dropped from the revised guidelines in favour of a case by case assessment. Neutralization Potential (NP) levels ranged from low to moderate (6 to 40 kg CaCO3/t). The lower levels of NP in some samples may indicate that these samples have a negligible potential to neutralize acidity, as the NP test typically overestimates NP.
The NP/AP ratio is commonly used to further assess the potential for ARD. The draft BC Guidelines suggests the following ABA screening criteria:
Table 4.1 NP/AP1 Acid-Base Screening Criteria Recommended in Draft BC Guidelines Screening Potential Comments Criteria for ARD NP/AP < 1 likely likely ARD generating unless sulphide minerals are non-reactive possibly ARD generating if NP is sufficiently unreactive or is 1 <= NP/AP < 2 possible depleted at a faster rate than sulphides not potentially ARD generating unless significant preferential 2 <= NP/AP <4 low exposure of sulphides along fracture planes, or extremely reactive sulphides in combination with insufficiently reactive NP NP/AP >= 4 none 1: NP = neutralizing potential, AP = acid potential
All of the samples fall within the “none” category, confirming that there is little potential for ARD.
The proposed GS will require a slight alteration to the existing topography of the site. A site development plan will be prepared by the Contractor, including planning considerations; site and design considerations; site development scheduling; selection of construction equipment; and
Final 4-2 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station site development details. This plan would be submitted as part of the package under the Lakes and Rivers Improvements Act (LRIA) to the MNR.
No effects on geology and physiography are anticipated as a result of the operation of the proposed GS.
Soils on the proposed GS site consist of loose natural soil deposits, greyish brown silt, with traces of sand and clay. The silt natural water content is 29%. A granitic boulder layer, with cobbles and gravel in a sandy matrix was observed above the bedrock.
During construction, soil erosion generally results from precipitation and runoff, or wind action on the disturbed terrain surfaces as a result of the removal of vegetative cover, alteration of topography and improper restoration. All construction work should be conducted so as to avoid unnecessary disturbance of the ground by the placement or excavation of materials, the disruption of established natural surface and subsurface, or the disturbance of natural vegetation cover that is to be preserved.
Till and gully erosion caused by channelized overland flow can be a major source of soil erosion. Sheet erosion can be an additional source of sediment.
Erosion and sediment control will be an integral component of the construction planning process. All personnel involved in the construction will be briefed on erosion and sediment control including engineers, contractors, inspectors and environmental staff. In general, the following guidelines will be applied in the development of the Erosion and Sediment Control Plan:
• Fitting of proposed works to the terrain; • Timing of grading and construction activities to minimize soil exposure; • Retention of existing vegetation where feasible; • Restriction of the use of heavy construction equipment to within the approved work areas to minimize soil disturbance and vegetation destruction; • Storage of stripped soil at upland locations; • Implementation of erosion control measures, e.g. rip rap berms underlain by filter geotextile, straw bales used as filters, silt fencing along the shoreline and/or mulching for interim stabilization; • Diversion of runoff away from exposed areas; • Minimization of the length and steepness of slopes; • Maintenance of low runoff velocities; • Design of drainage works, such as ditches and outfalls, to handle concentrated runoff; • Retention of sediment on site; • Routine inspection and maintenance of erosion and sediment control measures; and, • Revegetation of disturbed areas by seeding and/or planting following construction as soon as seasonal conditions permit.
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After construction of the proposed GS, the site will be rehabilitated. A Site Rehabilitation Plan including planning considerations, soil stabilization and re-vegetation will be prepared.
Dust may be generated during the construction of the proposed GS due to heavy equipment movement. Dust generation during dry, windy conditions can be controlled by water trucks and/or sprinklers as necessary to reduce dust to acceptable levels (Cheminfo 2005).
The implementation of the Erosion and Sediment Control Plan and the Site Rehabilitation Plan during construction and rehabilitation will obviate or minimize potential effects on soils.
Incidental spills of oil, gas, diesel fuel and other liquids to the environment could occur during construction. In addition, sanitary and other wastes will be generated during construction. Fuelling and lubrication of construction equipment should be carried out in a manner that minimizes the possibility of releases to the environment. Measures for containment and cleanup of contaminant releases should be followed to minimize contamination of the natural environment, e.g., placement of fuel tanks and generators on plastic sheets bermed around the edges, and use of suitable hydrocarbon absorbent material for cleanup and approved landfill or other disposal. Any spills with the potential to create an impact to the environment should be reported to the MOE as required by provincial spills legislation. Interim sanitary waste collection and availability of treatment facilities should be arranged for the duration of the construction period. All construction waste, wash water and wastewater should be disposed of in accordance with regulatory requirements.
A Hazardous Materials Management Plan, a Waste Management Plan and a Spills Emergency Preparedness and Response Plan will be developed as part of a broader Environmental Management Plan that is to be developed and implemented by the Contractor.
The implementation of these pollution prevention plans will obviate or minimize the environmental effects of accidental releases to the natural environment.
The operation of the hydroelectric facility is not expected to have an effect on property soils. Therefore, no mitigation is required.
4.2.2 Forest Resources and Vegetation
A small amount of forest clearing is required for the Proposed Undertaking. A full description of the impact of this clearing on forest resources and vegetation is described in the Terrestrial Environment Technical Support Document. The full description of the identification, assessment and selection of a preferred transmission route is provided in the Transmission Line Assessment.
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The Proposed GS, will have a small area (less than 1 ha) of vegetation and trees, predominantly semi-mature to mature. Balsam Poplar, Trembling Aspen and White Birch, cleared for the penstock, powerhouse and tailrace, and any other ancillary infrastructures.
The proposed transmission line is to follow the old utility line and will impact approximately 11 hectares of land. Most of the area affected is younger regenerating conifer plantations or naturally regenerated hardwoods and mixedwoods. There was a small amount of mature mixed wood impacted mainly at the western end of the proposed transmission line.
The proposed transmission line impacts a total of 10.2 hectares of forest and 0.4 hectares of non-forested land. The forest affected includes 4.98 hectares of Free to Grow (FTG) natural regeneration or mature stands, 2.71 hectares of FTG Jack Pine and Black Spruce plantations, 1.70 hectares of low stocked Jack Pine and Black Spruce plantations, and 0.77 hectares of low stocked naturally regenerated area. It appears as if silvicultural investments occurred on 4.41 hectares of this land and the loss can be compensated by OPG if necessary by paying approximately $5,000 to the Forest Renewal Trust Fund.
The total wood volume impacted was estimated to be only 75 cubic metres, including 30 cubic metres of Black and White Spruce, 10 cubic metres of Eastern White Cedar, 19 cubic metres of Trembling Aspen and 16 cubic metres of White Birch.
A small Forest Resource License (FRL) would be required from MNR to harvest the timber from the selected route. Wood would have to be skidded out to the existing roads to allow it to be utilized. Stumpage fees would be due to the Crown on the 75 cubic metres of merchantable volume. The volume is too small to be easily marketable, given its locations far from the mills. Therefore, one other option may be to provide the entire volume to MFN as fuelwood if that is considered acceptable to MNR.
Incidentally, it is of note that White Pine is normally left standing after harvest by Tembec. Occasionally, there may be one contractor who harvests White Pine. There are a few large White Pine trees observed within or adjacent to the preferred alternative corridor and these may have to be cut to allow for the transmission line. If the trees are on the edge of the transmission line corridor they may be avoided by re-aligning the corridor. This should be addressed as part of the forest resource license.
Based on vegetation surveys of those locations likely to be affected by construction activities, no significant or unusual areas of native vegetation are identified that would preclude or be affected by the works and activities of the proposed GS. In addition, no floral species documented at these clearing locations during the field surveys or within the local study area based on examination of the NHIC (2010) and EC CWS (2004) databases are designated to be at risk by COSEWIC (2010) or COSSARO (MNR 2010). In fact, all vegetation species observed during the field surveys are either ranked by NHIC (2010) as S5, i.e. very common in Ontario and
Final 4-5 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station demonstrably secure, or SE, i.e. exotic, not believed to be a native component of Ontario’s flora. Removal of these plant species will have negligible effect on their overall populations in Ontario.
Vegetation clearing will adhere to standard construction practices as listed below:
• Vegetation clearing should be restricted to the minimum necessary for construction activities; • Brush and trees should be felled into the area to be cleared to prevent damage to adjacent vegetation; • Branches overhanging the cleared area should be cut (pruned) cleanly and stubs should not be dressed; • Merchantable timber should be cut and neatly stacked for removal as requested by MNR; • Specimen trees marginal to the cleared area should be identified prior to construction, flagged and protected from damage, where possible; • All slash, brush, roots and stumps are typically raked into piles for burning or disposed in a manner prescribed by MNR; and, • Slash material should not be stored near the Mattagami River.
Both Mattagami First Nation and the Métis Nation of Ontario indicated that they have concerns with the use of herbicides to suppress vegetation along transmission corridors during operations. As such, OPG has agreed that there would be no chemical suppression of vegetation and that mechanical means would be employed instead.
4.2.3 Wetlands and Environmentally Significant Areas
There are no environmentally significant areas within a 25-km radius of the Proposed Undertaking and therefore construction and operation of the proposed GS will have no effect on environmentally significant areas.
4.2.4 Wildlife
All the land around the proposed GS remains in native vegetation and therefore wildlife habitat is not a limiting factor to animal survival and distribution. All of the herpetofauna species are ranked by NHIC (2010) as common and very common. Most native bird and mammal species likely present in the study area are ranked by NHIC (2010) as S4 and S5, i.e. common, and very common in Ontario, respectively.
As indicated previously, the distribution range of only one SARA Schedule 1 species at risk, the monarch butterfly, overlaps with the development site (EC CWS 2004). With the absence of milkweed, the proposed GS site does not provide a preferred habitat for the monarch butterfly. According to NHIC (2010), the monarch butterfly has not been recorded within the study area.
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Based on the proposed GS location relative to any environmentally significant areas (Section 3.4), the proposed GS will not affect significant wildlife habitats; thereby conforming with the Wildlife Policy of Canada (CWS 1990) and the Provincial Policy Statement (OMMAH 2005).
The construction disturbance will be sufficiently local that little displacement of wildlife will occur. Any resident animals can relocate temporarily to avoid noise and disturbance associated with construction works and activities.
A number of terrestrial bird species are likely locally resident and may nest on the property associated with the proposed undertaking. Most of these species are protected under the Migratory Birds Convention Act (MBCA). The Canadian Wildlife Service (CWS) has stipulated that vegetation clearing should not be undertaken during the breeding season of migratory birds in order to avoid the destruction of any bird nests. Specifically, clearing should not take place between May 1st and July 31st in northern Ontario. Otherwise, a breeding bird survey must be conducted by a qualified avian biologist and any nests found must not be disturbed by the clearing activity until the young have fledged. A buffer zone with a 50 metres allowance restricting active construction activities is usually applied around a nest. The CWS will be consulted for the appropriate mitigation measures. To preclude the potential institution of a buffer zone that may affect construction activities, it is recommended that vegetation (including grubbing) be removed prior to nesting season initiation (May 1st), or after nesting season completion (July 31st).
Once construction of the proposed GS is completed, any displaced animals could reoccupy the habitat created on the rehabilitated areas of the property and the habitat associated with the natural and cultural vegetation communities not directly affected by construction activities.
During operation, noise will be generated within the proposed GS. This steady noise from the plant will be similar to that at other facilities and not elicit an adverse reaction from nearby wildlife that will get accustomed to the noise over time.
Overall, the construction and operation of the proposed GS will have minimal effect on wildlife populations or the wildlife-carrying capacity of the area.
4.2.5 Summary and Conclusions
During the construction of the proposed GS, potential impacts on the terrestrial environment may occur due to soil erosion and fugitive dust; accidental spills; noise and human activity; and forest/vegetation clearing. Based on the assessment of the available baseline information and potential effects, as well as the implementation of the recommended mitigative measures, SENES Consultants Ltd. concludes that effects during construction can be mitigated. They will be minimal, localized and short-term.
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During the operations of the proposed GS, potential impacts on the terrestrial environment may occur due to noise and accident spills. Based on assessment of the baseline information and potential effects, SENES concludes that the operation of the proposed GS will have negligible effects on the terrestrial environment.
Environmental protection during the proposed GS construction and operation will be ensured by adherence to a site-specific Environmental Management Plan, as well as compliance with regulatory standards and guidelines.
The Environmental Management Plan for the Proposed Undertaking will ensure that environmental protection will be achieved by describing government agency requirements, OPG policy, project commitments and recommended mitigation measures to be undertaken. The Environmental Management Plan will include an Erosion and Sediment Control Plan, Spills Emergency Preparedness and Response Plan, Hazardous Materials Management Plan, Waste Management Plan and Site Rehabilitation Plan.
Table 4.2 below summarizes potential construction and operation effects, the recommended mitigative/remedial measures to minimize or obviate these impacts and the net effects.
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Table 4.2 Summary of Potential Effects and Recommended Mitigative/ Remedial Measures Effect Recommended Mitigative / Remedial Measure Net Effect Construction Soil erosion • Adherence to Erosion and Sediment Control Negligible effect Plan. Fugitive dust • Use of water trucks and/or sprinklers Negligible effect (Cheminfo 2005). Incidental spills of • Adherence to Spills Emergency Preparedness Negligible effect oil, gasoline and and Response Plan. other liquids during construction Hazardous • Adherence to Hazardous Materials Negligible effect Materials/Waste Management Plan and Waste Management Plan. • Waste disposal in accordance with regulatory requirements. Displacement of • Vegetation clearing to be undertaken outside Negligible effect nesting birds the migratory bird breeding season (01 May to 31 July). Vegetation clearing • Implementation of the Site Rehabilitation Plan. Negligible effect Blasting • Adherence to blasting engineer Negligible effect recommendations. Noise • Use of well-maintained equipment and noise Negligible effect silencers (as required). Operation Noise • Ambient noise levels to remain unchanged. Negligible effect Incidental spills of • Adherence to Spills Emergency Preparedness Negligible effect oil, gasoline and and Response Plan. other liquids during operation
4.3 Aquatic Environment
The available environmental baseline information and site-specific aquatic habitat and fisheries survey findings provided the basis for an assessment of potential construction and operational effects on the aquatic environment. The significance of potential impacts is based on their magnitude, duration and extent after the implementation of recommended mitigative measures. The following sections detail the potential impacts and mitigating measures that directly affect fish and fish habitat, and provide an analysis of the residual impacts for the different phases and components of the Proposed Undertaking.
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4.3.1 Potential Construction Impacts and Associated Mitigation
4.3.1.1 Water Quality
Erosion and Sediment Control Erosion and sediment control will be an integral component of the construction planning process. All personnel involved with the proposed works will be briefed on erosion and sediment control including engineers, contractors, inspectors and environmental staff. Erosion and sedimentation control measures are outlined in Section 4.2.1.
Management and Control of Hazardous Material, Construction Wastes, and Accidental Spills All materials and equipment used for the purpose of site preparation and project completion should be operated and stored in a manner that prevents any deleterious substance (e.g. petroleum products, debris etc.) from entering the water. Mitigation is further described in Section 4.2.1. There is a potential for accidental loss of cement during surface application. Any dripped cement should be recovered from the river bottom for suitable disposal prior to temporary cofferdam removal. All trash and other solid debris should also be collected for appropriate disposal.
A Hazardous Materials Management Plan, Waste Management Plan and a Spills Emergency Preparedness and Response Plan will be developed as part of the broader Environmental Management Plan. The implementation of these pollution prevention plans will obviate or minimize the environmental effects of accidental releases to the natural environment that have the potential to affect water quality.
Use of Explosives Blasting will likely be required to facilitate new powerhouse and/or ancillary infrastructure construction for the Proposed Undertaking.
If required, explosives used in construction will be closely controlled, with their use restricted to authorized personnel who have been trained in the use of explosives in a manner so as to minimize impacts on the environment. Appropriate government agencies and the local residents will be informed of the blasting schedule in advance of construction, as well as just prior to the detonation program. All necessary permits will be obtained by the Design-Build- Contractor (DBC), who will also comply with all legal requirements in connection with the use, storage and transportation of explosives, including, but not limited to, the Canada Explosives Act and the Transportation of Dangerous Goods Act. The DBC will be required to retain a consulting engineer with technical expertise in blasting to provide advice on maximum loading of explosives for all blasting, as well as an engineering report indicating recommended charges and blasting methods to be used at specific locations. All blasting will occur in such a way as to be in compliance with federal regulations and directions.
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Blasting could have a potential effect on groundwater quality and flow in the immediate vicinity of the blasting operations (Fitchko et al., 1998). Minimization of the physical effects of blasting will be ensured by following the recommendations of the blasting engineer.
4.3.1.2 Aquatic Habitat
General Considerations
Timing of In-water Work In-water construction activities should be timed to avoid the spawning and incubation period of spring spawning fishes such as walleye, which typically excludes in-water work from April 1 to June 20.
In-water construction activities should be timed to avoid the spawning and incubation period of lake whitefish. The DFO guidelines suggest September 15 to May 15 for all of northeastern Ontario (Fisheries and Oceans Canada, 2010), but based upon the lake whitefish spawning investigations at the Mattagami Lake Dam, it is believed that spawning within the Mattagami River at this location does not commence until well after October 1, usually during the second half of October.
Use of Explosives Blasting should adhere to the Fisheries and Oceans Guidelines for the Use of Explosives In or Near Canadian Fisheries Waters (http://www.dfo-mpo.gc.ca/canwaters-eauxcan/infocentre/ guidelines-conseils/guides/explosguide/chap3_e.asp#GUIDELINES).
Plankton Plankton populations will not be affected by the project.
Benthic Macroinvertebrates A few construction activities may have a temporary localized adverse effect on benthic macroinvertebrate communities on the surface and within the substrate. The extent of disruption depends on the type of bottom substrate, the extent of the disturbed area, any resultant turbidity and sedimentation, and the timing of construction. The substrate in the areas to be excavated consists primarily of boulder, cobble, gravel and/or sand over bedrock, or bedrock. The placement of rock fill over this type of similar substrate will minimize any detrimental effect on the benthic macroinvertebrate communities.
With the use of the larger-size rockfill, sufficient interstitial spaces will be available for the survival and migration of mobile benthic fauna. Recovery after activity is expected to be rapid. Recovery is defined as the return of aquatic biotypes after disturbance to an abundance and diversity comparable to that in an adjacent undisturbed control area (Rosenberg and Snow, 1977). The principal mechanism of recolonization by invertebrates is drift (Luedtke and Brusven, 1976; Williams and Hynes, 1977), but other mechanisms, such as lateral migration,
Final 4-11 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station vertical migration from within the hyporheic zone (i.e., after burial) and larval recruitment from aerial sources are also important (Luedtke and Brusven, 1976; Williams and Hynes, 1977; Griffiths and Walton, 1978; Hirsch et al., 1978). The rate of recovery is dependent on ambient environmental conditions, the type of organisms present and the size of the disturbed area. In general, there will be less impact upon benthic communities associated with a naturally variable, high energy environment. The benthic organisms are adapted to the high-energy, unstable conditions, and have life cycles that allow them to better withstand these stresses (Hirsch et al., 1978).
Site-specific Fish Habitat Considerations
Intake channel Alteration of the existing Mattagami Lake Dam to include an intake channel will not result in any permanent loss of fish habitat. A small area of bedrock riverbed immediately downstream of the two west-most sluice gates will be altered and covered by the intake structure (Figure 3.9). Given the bedrock nature of this small area and its inaccessibility to fish, as well as the fact that it is only wet when water is spilled across it when either of the two western-most sluice gates are open, this is not considered fish habitat (Aquatic TSD, Appendix A: Photograph 21). No in- water work is proposed on the upstream side of the dam, except for the removal of the old rock- filled crib structure.
Removal of old rock-filled wooden crib structure With the proposed utilization of the two western-most sluice gates to divert river flow for the proposed GS, the remains of an old rock-filled crib structure located immediately upstream of the dam at this location (Figure 3-9; Aquatic TSD, Appendix A: Photograph 3) must be removed to allow the uninhibited flow of water into the GS. This old crib structure will be dismantled and its material removed to an off-site approved disposal area. To maintain the habitat function that was provided by the rock and timber crib, new, similarly sized clean rock material, will be placed in a similar configuration in the vicinity of the floating boom (Aquatic TSD, Appendix A: Photograph 2). To improve the utilization of this habitat by fish, the new habitat should be located in deeper water so that it remains submerged during the late winter drawdown of Mattagami Lake.
These old rock-filled wooden cribs are not large, and are primarily composed of large rocks and old logs, and therefore are not expected to generate much suspended sediments when they are dismantled. Since the surrounding lake substrates are primarily fine, any deposition from the small amount of fine material that may be attached to this wood and rock structure will not significantly impact surrounding habitats. Its removal can be accomplished without the use of a cofferdam, as the installation and subsequent removal of a cofferdam would likely constitute a greater impact than the actual work. However, a silt curtain may be warranted. If this work is undertaken within the in-water construction window for this site (June 20 to September 15), no negative impacts to fish and fish habitat are anticipated.
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Penstock construction The penstock and associated protection works will be constructed above the average high water level on the west shore, and therefore will not impact fish habitat, providing that the appropriate general mitigation measures described at the beginning of Section 4.0 are applied.
Powerhouse and tailrace construction While the construction methods presented here outline the basic principles that will be used to minimize the environmental impact of this work, the final design of the tailrace channel and cofferdam are the contractor’s responsibility. The construction methods presented here reflect the components of the DFO Risk Management Framework (Fisheries and Oceans Canada, 2006) and have been discussed with DFO. Generally, the powerhouse and part of the tailrace channel will be constructed in dry conditions inside a cofferdam located along the west shoreline (Aquatic TSD, Appendix A: Photograph 22). The general layout is provided in Figure 4.1.
Figure 4.1 General Project Layout
As noted above these are preliminary plans and will be subject to final stamped drawings from the contractor. The powerhouse cofferdam will be constructed along the west shore of the river, downstream from the road bridge (Aquatic TSD, Appendix A: Photograph 22). The construction will occur in the dry over a period of 3 to 4 weeks during the low flow period, when the dam can be shut down (if necessary) with only leakage flow to the downstream river. No in-water work will occur in the tailrace area during the spawning or incubation periods of walleye and lake whitefish (i.e. the work should normally be done between June 20 and September 15). The
Final 4-13 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station cofferdam toe on the river side will correspond roughly to just below the waterline associated with the average annual flow of 30 cubic metres per second, and at that water level would reduce the wetted habitat area by approximately 150 square metres. The cofferdam will stay in place for about 2 years, and be designed according to the latest Ontario Dam Safety Guidelines. The habitat area that will temporarily be unavailable to fish during this period, is not spawning habitat for lake whitefish or walleye. The initial cofferdam configuration is shown in Figure 4-2.
Figure 4.2 Initial Cofferdam Location
During the excavation and initial construction of the powerhouse and part of the tailrace channel, the excavation pit will need to be maintained in a dry condition. Surface water and leakages will be collected and pumped from the pit to a settling pond or a filter bag, or a combination of both, to remove as much suspended material as possible from the discharge water before it re-enters the river. Contouring and shaping of the tailrace channel will be conducted in the dry behind the cofferdam to the extent possible. Once the powerhouse is advanced to the point that its outer shell within the pit is finished and watertight, and the draft tube gates can be sealed, the cofferdam can be removed. Figure 4.3 shows the construction advanced to the point that the cofferdam can be removed.
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Figure 4.3 Work-site Configuration Immediately Prior to Cofferdam Removal
The cofferdam will be removed and the tailrace completed during the traditional low flow period, and during the accepted in-water work window (i.e. June 20 to September 15th), as indicated earlier. The existing Mattagami Lake Dam will be closed, allowing only leakage during the 2 to 3 week duration of this work. This should result in water levels that are low enough for the cofferdam to be removed in the dry (Figure 4.4). As the cofferdam is removed, the contouring and shaping of the tailrace can be extended outward as much as possible in the dry.
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Figure 4.4 Cofferdam Removal and Outward Extension of Tailrace into River
The tailrace extension into the river will require the re-contouring of approximately 500 square metres of riverbed, to allow for the efficient flow of water exiting the tailrace. Figure 4.5 is a plan view of the proposed works, showing the estimated extent of the tailrace contouring and shaping that may be required to smooth the transition between the tailrace to the river. At the point in time when work in the wetted portion of the river cannot be avoided, a silt curtain system will be installed to enclose the tailrace footprint area. For such a small amount of excavation within relatively clean granular substrates, a silt curtain system, rather than a second cofferdam, would be the best choice to minimize impacts to the surrounding habitats. Utilizing a new cofferdam, rather than a silt curtain, would extend the area of direct impact to include the base of the cofferdam, possibly resulting in a doubling of the area of riverbed disturbed, and increasing the duration of that disturbance. Within the area contained by the silt curtain, the tailrace can be deepened and extended to blend with the contours of the surrounding riverbed. Backhoe bucket movement speed can be adjusted to minimize the suspension of material when warranted. The native riverbed material will be used to re-contour the in-water area as shown in Figure 4.5, with the coarser materials (cobble/small boulder) placed along the edge and sloped sides of the tailrace to provide potential spawning areas for walleye, and the finer materials (sand/gravel) placed in the deeper central portions of the tailrace to provide potential spawning areas for lake whitefish. Once the tailrace construction is complete, and all potentially erodible
Final 4-16 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station areas are stabilized and fine suspended material is cleaned-up, the tailrace silt curtain will be removed.
Re-contouring of the riverbed to accommodate the tailrace will not impact substrates used by spawning walleye. Re-contouring will shuffle some of the substrates where lake whitefish apparently spawn, but this is not expected to impact spawning since the overall substrate type will not be changed and lake whitefish spawn over a variety of substrates. Furthermore, as detailed in Section 3.3.2.4, sufficient water depth appears to be a significant condition for lake whitefish spawning, and the proposed tailrace and associated works are expected to slightly increase the area of deeper habitat in the vicinity of the tailrace (portion of Area B), creating conditions that are more favourable for lake whitefish spawning (see Section 4.3.2 below).
Figure 4.5 Plan View of the Proposed Tailrace Works
4.3.2 Operational Impacts
The proposed Undertaking will not substantively change the flow regime of the Mattagami River or the management of water levels within Mattagami Lake or Kenogamissi Lake. Operation of the proposed GS will respect the amended Water Management Plan and users will not detect changes in flow beyond the local study area. The following summarizes the expected impact to
Final 4-17 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station flow once the proposed GS is operational. Historical flows and elevations are included below in Figure 4.6 for reference.
Upstream of Mattagami Lake Dam, flow velocity changes will be limited to within a few metres of the dam. Currently, the velocity gradient occurs across all sluices dependent upon which stoplogs are pulled. Going forward, when the GS is in operation, a velocity gradient will preferentially occur at the proposed intake structure at the west end of the dam. This change is not expected to cause significant impact.
The proposed Undertaking will result in a reduction in flow within the area between the dam and the proposed GS which can be summarized in three scenarios.
1. In scenario one, flows are between the GS minimum rated flow (8-12 cms) and maximum rated flow (47 cms). Under these conditions, water previously passed through the dam will now pass through the intake structure and be diverted through the GS before returning to the river downstream. In order to preserve fish habitat in this area an ecological, or minimum, flow of 0.2 cms will be maintained throughout the year to prevent the area from becoming dewatered;
2. A second scenario is when flows are greater than the GS can utilize, in which case the additional flow will be passed through the dam. This scenario will increase the flows between the dam and GS as compared to scenario one, but total flow will continue to be passed downstream of the GS. Flows exceeding 47 cms are generally only expected during high flow season in early spring;
3. The third scenario occurs when the station is shut down due to insufficient water to run the GS at its minimum rated flow (below 8-12 cms) or from maintenance periods resulting in the facility being shut-down. In order to meet the downstream minimum flow requirement, flow through the dam would be increased to a minimum of 2.8 cms. Based on historical flow date, this scenario is most likely to occur during late summer.
Figure 4.6 below illustrates historical flows and levels for Mattagami Lake Dam between 1979 and 2009. Storage reservoirs were created to provide a means of storing water during high inflow periods, to be used for power generation during low inflow periods. High inflows during the fall are stored and used over the course of the winter when natural inflows are at their lowest. At the end of the winter, when the storages have been drawn down, the reservoirs are replenished by the high spring flows.
These graphs provide historical data for this facility over a number of years (generally 30 years) based on daily average levels and flows graphed on a weekly average. The average level/flows (50% time exceedence) for a given time period, along with 25% of time and 75% of time exceedence bands are also included.
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Figure 4.6 Mattagami Lake Dam (1979-2009)
Flow velocity changes immediately upstream of the Mattagami Lake Dam Local flow velocities within a few metres of the upstream side of the Mattagami Lake Dam will change from present. Instead of a velocity gradient occurring at any one sluice, series of sluices, or across all sluices, dependent upon which stoplogs are pulled, a velocity gradient will preferentially occur at the proposed intake structure at the west end of the dam. It is not thought that this will cause a significant impact upon local fish habitat or fish communities in Mattagami Lake, and therefore, no mitigation is proposed.
Flow reduction between the dam and the road bridge When the GS is in operation, potentially all flow up to a maximum of about 40 to 47 cubic metres per second would pass through the proposed intake structure and be diverted through the GS. Based upon the known hydrology of this site (Table 4.3), without provision of a minimum flow Area A would likely be dewatered, other than dam leakage, most of the time except for periods in March through June when the river flow is more likely to exceed the GS capacity. Therefore, to maintain the fish habitat found in this stretch of river, an ecological, or minimum, flow, is proposed to be released downstream of the dam.
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Table 4.3 Mattagami River Monthly Mean Flow for the Period 1950 to 2006 at Mattagami Lake Dam (OPG Data) Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Mean Flow (cms) 28.5 33.1 38.6 42.6 55.1 41.9 22.1 16.6 16.1 20.3 25.4 29.0 30.8
Habitat within Area A is not thought to contribute significantly to local fish production, or provide spawning habitat for downstream fish populations, since it is almost entirely bedrock with high flow velocity (Aquatic TSD, Appendix A: Photographs 5, 6 and 21). However, a deep bedrock pool located 40 metres upstream of the road bridge (Aquatic TSD, Figures 3.9 and 3.6; Appendix A: Photograph 6), provides non-critical and low productivity fish habitat.
As part of a study undertaken in 2008 in support of this project (Aquatic TSD, Appendix C), it was determined that to maintain the viability of fish habitat in the “bedrock pool” located 40 metres upstream of the bridge, an ecological flow of 0.2 cubic metres per second must be provided to maintain water quality as well as a maximum water depth of 11 centimetres at the outlet of the pool (See Transect S-3 in Photograph 1.4 of Appendix C, Aquatic TSD) to provide habitat connectivity with downstream aquatic habitats. To simplify compliance measurement and reporting, the minimum water level in the bedrock pool that corresponds with these conditions will be maintained and measured by OPG. If winter conditions (e.g. ice cover in bedrock pool) result in the inability of the water level gauge to accurately provide water levels, OPG staff will periodically assess the outlet depth by other means to ensure that the maximum depth of 11 centimetres is maintained at Transect S-3. As part of the final design of the proposed GS, there will be an arrangement for providing the minimum flow, other than leakage from the dam.
OPG has also committed to undertaking an effectiveness monitoring program of the post- construction functionality of the bedrock pool (see Section below).
A minor amendment to the Water Management Plan is anticipated to accommodate the minimum flow requirements described above. Further information on this can be found in the Public and Agency Consultation Technical Support Document.
Changes in flow pattern in the vicinity of the proposed tailrace The discharge from the proposed tailrace will change the velocity and orientation of the existing flow patterns in portions of Area B (Figure 3.9; Appendix A: Photographs 8 and 22, Aquatic TSD). Area B contains approximately 6% of the spawning habitat for walleye and something less than 50% of the spawning habitat for lake whitefish that occurs between the Mattagami Lake Dam and Kenogamissi Lake. Downstream of Area B (Figure 3.9), flow velocity and volume will not differ between pre- and post development (Figures 4.7 to 4.14) and therefore effects upon spawning habitat in these areas will not occur.
To mitigate the potential impacts to the walleye spawning in Area B (Figures 3.10, 3.11, 3.12 and 3.13), flow modeling was conducted (Aquatic TSD, Appendix B) and the tailrace orientation was adjusted accordingly to minimize the changes in flow velocity within known areas of walleye
Final 4-20 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station spawning habitat. The modelling results for two flow rates, at the tailrace orientation that has the least affect upon flow velocity in known walleye spawning locations, are presented in Figures 4.6 to 4.13. A comparison of Figure 4.6 to 4.9 with the spawning locations shown in Figures 3.10 to 3.13, suggest that the proposed tailrace will have little effect upon walleye spawning habitat conditions.
Lake whitefish are known to spawn over a variety of substrates, compared to the relatively narrow range of substrate size for walleye. Also, lake whitefish prefer deeper water for spawning than walleye, possibly with a minimum depth of approximately 2 metres (Becker, 1983), and are known to spawn in both lake and riverine habitats. Therefore, it appears that lake whitefish do not have the same narrow range of spawning habitat requirements as walleye, and are likely less susceptible to habitat change. Since the construction or the operation of the GS will not eliminate any of the existing habitat types within Area B, but will only shift their locations, it is thought that the proposed changes in flow pattern within Area B will not have a negative impact upon lake whitefish spawning. Also, it is possible that spawning habitat for lake whitefish within Area B may slightly improve post-construction, as the proposed tailrace is expected to slightly increase the area of deeper habitat in Area B, and create a deeper area with low velocity water between the tailrace outflow and the upstream road bridge (Figures 4.7 and 4.13) creating conditions that are more commonly found in portions of Area D.
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Figure 4.7 Flow Velocities in Area B and the Upstream Portion of Area C Under Existing Conditions at a River Flow of 14 cms
Figure 4.8 Flow Velocities in Area B and the Upstream Portion of Area C Under the Proposed GS Operating Conditions at a River Flow of 14 cms
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Figure 4.9 Area Where Typical Walleye Spawning Velocities Occur in Area B and the Upstream Portion of Area C Under Existing Conditions at a River Flow of 14 cms
Figure 4.10 Area Where Typical Walleye Spawning Velocities Will Occur in Area B and the Upstream Portion of Area C Under the Proposed GS Operating Conditions at a River Flow of 14 cms
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Figure 4.11 Flow Velocities in Area B and the Upstream Portion of Area C Under Existing Conditions at a River Flow of 39 cms
Figure 4.12 Flow Velocities in Area B and the Upstream Portion of Area C Under the Proposed GS Operating Conditions at a River Flow of 39 cms
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Figure 4.13 Area Where Typical Walleye Spawning Velocities Occur in Area B and the Upstream Portion of Area C Under Existing Conditions at a River Flow of 39 cms
Figure 4.14 Areas Where Typical Walleye Spawning Velocities will Occur in Area B and the Upstream Portion of Area C Under the Proposed GS Operating Conditions at a River Flow of 39 cms
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Changes in flow between the proposed tailrace and downstream Kenogamissi Lake The proposed GS will be operated within the parameters and obligations that are stipulated in the Mattagami River System Water Management Plan, as amended (OPG et al, 2006). For most of a typical year, this will result in little substantive change between pre-operational flows and post-operational flows downstream of the proposed powerhouse to Kenogamissi Lake. This will almost always be the case during fall, winter and early spring when river flow is sufficient to operate the GS, and during the walleye spawning and incubation period in mid to late spring when a minimum flow of 12-15 cubic metres per second is required. However, in addition to shutdowns for repairs or other technical issues, the GS must be shut down when there is insufficient water storage to allow the generating unit to operate at its minimum rated capacity (estimated to be 20%). This would occur when the reservoir’s storage capacity is low and inflows are less than 8-12 cubic metres per second (assuming a station flow capacity of 40- 47 cubic metres per second).
A minimum 2.8 cubic metres per second flow (called “Ecological Flow”) as discussed with the MNR and the DFO will be released for the duration of the year outside of the walleye spawning, incubation, hatch and dispersal period, to maintain the fish habitat in the 550 metre long river section between the tailrace of the new station and Kenogamissi Lake when the unit is not operating. The agreed-upon flow requirement balances the net economic, social and environmental benefits of the Proposed Undertaking at this site.
The 2.8 cubic metres per second minimum flow was the compromise value between the 3.2 cubic metres per second flow thought to be adequate by MNR, and the 2.5 cubic metres per second thought to be adequate by OPG, that were observed during a series of demonstration flows and associated field measurements undertaken September 8 – 11, 2008 (Aquatic TSD, Appendix C). The monitoring plan discussed in Section 4.3 and provided in Aquatic TSD, Appendix E, will identify any environmental issues that may arise through the use of 2.8 cubic metres per second as the minimum flow. OPG is committed to addressing any potential issues that are identified.
A minor amendment to the Water Management Plan is anticipated to accommodate the minimum flow requirements described above. Further information on this can be found in the Public and Agency Consultation Technical Support Document.
The frequencies of occurrence of various flows for the period 1986 to 2006 are provided in Table 4.4. Flows less than 8 cubic metres per second have occurred in all years from 1987 to 2006, except 2003. In seven of these years the flow was less than 8 cubic metres per second for 15 days or less. These low flow events almost always occur within the months of July to September. During the period 1987 to 2006, the number of days with river flow less than 2.8 cubic metres per second was approximately 191 (84+68+39 from Table 4.4), which is approximately 2.6% of the time, and on 84 of these days there was no flow through the dam. Zero discharge is achieved by jacking down the stop logs in the dam, and is undertaken when inflows are extremely low in order to maintain water levels in Mattagami Lake.
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Table 4.4 Frequency of Average Daily Flow Discharged from the Mattagami Lake Dam Over the Period 1987 to 2006 Flow (cms) Frequency (days) Percent (%) >=12 5,683 77.9 11 – 12 177 2.4 10 – 11 172 2.4 9 – 10 134 1.8 8 - 9 115 1.6 7 - 8 112 1.5 6 - 7 244 3.3 5 - 6 166 2.3 4 - 5 171 2.3 3 - 4 103 1.4 2 - 3 39 0.5 >0 -<2 68 0.9 0 84 1.2 Total 7,293 99.9
Presently, OPG operates the dam solely to meet their commitments under the Mattagami River System Water Management Plan (OPG et al, 2006). Based on the historical flows, and assuming that the GS would be operated for as much time as possible during dry periods (i.e. at 8 cubic metres per second, whenever that was available) the number of days that the facility would have passed the minimum flow of 2.8 cubic metres per second would have been approximately 575 days. Following construction of the GS, however, the operation would be adjusted, within the limits of the water management plan, to maximize the operation of the GS and thus minimize the period of time that the plant will be discharging the minimum flow of 2.8 cubic metres per second.
A series of photographs are provided in Appendix D of the Aquatic TSD, which illustrate the effect of flow changes upon habitat over a range of approximate flows from 2.4 to 13.3 cubic metres per second. Furthermore, the minimum flow study provided in Appendix C of the Aquatic TSD contains a series of photographs at precise locations and at precise flow rate, that also illustrates the relationship of flow rate and habitat, but over the range of 1.2 to 4.5 cubic metres per second. Based upon these photographs, no habitat components are lost at flows as low as 1.2 cubic metres per second. As well, no riffles are dewatered, nor do they become barriers to fish movement at flows as low as 1.2 cubic metres per second. A precise survey, undertaken as part of the minimum flow study, showed that the difference between the wetted area at a flow of 4.5 cubic metres per second and that at 3.2 cubic metres per second was about 4%, and the difference in wetted area between flows of 4.5 and 2.5 cubic metres per second was about 7.9%. Combined with a careful comparison of photographs taken at 12 cubic metres per second, it is estimated that the wetted area would be reduced by about 10% when flows are reduced from 12 to 2.8 cubic metres per second. It is expected that during dryer years when it becomes necessary to alternate between operating the GS at 8-12 cubic metres per
Final 4-27 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station second and shutting it down and passing 2.8 cubic metres per second of water to maintain downstream aquatic habitats, that this will almost always occur sometime within July, August, and September, when there is no spawning for any of the fish known to occur in this section of river.
The reduction of flows to 2.8 cubic metres per second during the lake whitefish spawning period will likely have little impact upon spawning success. It is inferred from the scientific literature on this species that temperature is likely the primary cue for the initiation of spawning, and so lower flows should not affect the initiation of the spawning run. During the spawning run, lake whitefish spawn in the deep pools within this section of river, which are not appreciably different at 2.8 cubic metres per second than they are at 12 cubic metres per second. There is also sufficient water depth along this length of river, at 2.8 metres per second, to allow lake whitefish access to both known spawning areas.
Some aspects of the operation of the proposed GS will likely benefit fish habitat downstream of the GS. The number of days with flows less than 2.8 cubic metres per second will, in theory, be eliminated, removing the potential of zero flow at critical periods that might otherwise severely limit a fish population or a fish population year-class, or populations of benthic invertebrates. Riverine habitats, as well as their attendent fish and invertebrate communities, may also benefit from the improved precision of flow control afforded by the proposed GS, due to the incremental and remote operation of the proposed spill gate, headworks, and powerhouse bypass pipe, compared to the coarser and less timely adjustments afforded by the existing manual stop-log operation. More stable flows during the walleye spawning period may improve spawning success. However, those less mobile organisms, such as benthic invertebrates, which may have colonized habitats in shallower water over periods of extended higher flows, may be negatively affected when the GS is shutdown under conditions that allow only 2.8 cubic metres per second to be passed.
Information generated during the September 2008 minimum flow study (Aquatic TSD, Appendix C) is used here to provide an estimate of the potential effect upon benthic invertebrates when flows are reduced to 2.8 cubic metres per second when the GS is shutdown. That study showed that the difference between the wetted area at a flow of 4.5 cubic metres per second and that at 3.2 cubic metres per second was about 4%, and the difference in wetted area between flows of 4.5 and 2.5 cubic metres per second was about 7.9%. Therefore, a flow of 2.8 cubic metres per second would be about a 6% reduction of area from a flow of 4.5 cubic metres per second. Even when the flow is 12-15 cubic metres per second, because of the channel shape, the apparent difference between the wetted area at 12-15 cubic metres per second and that at 4.5 cubic metres per second is small, and so we estimate that the reduction in wetted area, by reducing the flow from 12 to 2.8 cubic metres per second, would be about 10%. However, a short-term event that periodically reduces the wetted area by 10% does not translate directly to a 10% loss of the benthic invertebrate community, but will be somewhat less. This is due to the fact that (1) the benthic invertebrates of these habitats are adapted to fluctuating flows and therefore some within the dewatered area will escape by either moving
Final 4-28 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station vertically down into the substrate or laterally to the wetted portion of stream; and, (2) benthic invertebrate life cycles are such that only some of the community members would be affected on a given occasion.
4.3.3 Monitoring Plan
A proposed monitoring plan is provided in Appendix E of the Aquatic TSD. It will further document walleye and lake whitefish spawning under existing conditions and following development, as well as the effect of minimum flows upon fish habitat within the bedrock pool upstream of the GS tailrace, and within the 550 metres of river between the tailrace and Kenogamissi Lake.
The status of the lake whitefish population in Kenogamissi Lake was previously identified in the WMP as an information GAP. To address this gap in the WMP, coincident with the operation of the proposed GS at Mattagami Lake Dam, OPG has agreed to contribute funds to the MNR for the long-tem monitoring (20 years) of Lake Whitefish.
4.3.4 Summary and Conclusions
This technical support document provides an aquatic environmental baseline, as well as the potential environmental effects of the proposed project and the recommended mitigative measures to minimize these effects.
The variety of habitats and habitat conditions in the study area can provide one or more of the spawning, nursery, foraging, over-wintering, juvenile, and adult habitat requirements for the fishes that reside in this section of the Mattagami River system. Between the Mattagami Lake Dam and Kenogamissi Lake the river provides important spawning habitat for some fish species, including walleye and lake whitefish, that reside in this section of the Mattagami River and in Kenogamissi Lake. The walleye is an important game fish in the Timmins area, and the lake whitefish is an important commercial and recreational fish. No fish species considered at- risk occurs in the vicinity of the Mattagami Lake Dam or the proposed GS.
Provided that the recommended mitigation measures are implemented, it is our opinion that the development of the Mattagami Lake Dam site, and the subsequent operation of the proposed GS, will not have a significant or measurable impact upon the composition or production of the Mattagami River fish community.
The key points of this assessment are as follows:
• The mitigation measures proposed to protect critical walleye and lake whitefish spawning habitats are believed to result in no net loss of spawning habitat. • There will be no changes in the volume of water, and no significant changes in water velocity, passing over the critical walleye spawning habitat downstream of the
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powerhouse during the respective spawning and incubation periods for these species. • It is believed that the thoughtful design of the GS in combination with the general mitigation measures proposed will prevent harmful alteration, disruption or destruction (HADD) of fish habitat, or a measurable change in habitat productive capacity. • The areas that will be directly altered do not serve a critical habitat function during the in- water work window and, although they do contain fish, the fact that they will be temporarily unavailable is not expected to have a significant impact on the productive capacity of the system. • Following the completion of construction, the total amount of habitat will be unchanged.
During construction, potential impacts on the aquatic environment may occur due to in-water construction activities, blasting, soil erosion and turbidity generation, and accidental spills. Based on an assessment of the available baseline information and potential effects, as well as the implementation of the recommended mitigative measures, SENES concludes that effects during construction will be minimal, localized and short-term.
During operations, potential impacts on the aquatic environment may occur due to accidental spills. Based on assessment of the baseline information and potential effects, as well as the implementation of the recommended mitigative measures, SENES concludes that the operation will have negligible effects on the aquatic environment.
Environmental protection during the proposed GS construction and operation will be ensured by adherence to the site-specific Environmental Management Plans, as well as compliance with regulatory standards and guidelines.
An Environmental Management Plan for the project will ensure that environmental protection will be achieved by describing government agency requirements, OPG policy, project commitments and recommended mitigation measures to be undertaken. The Environmental Management Plan will include the Erosion and Sediment Control Plan, Spills Emergency Preparedness and Response Plan, Hazardous Materials Management Plan and Waste Management Plan.
Table 4.5 summarizes potential construction and operation effects, the recommended mitigative/remedial measures to minimize or obviate these impacts and the net effects.
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Table 4.5 Summary of Potential Effects and Recommended Mitigative/ Remedial Measures Effect/Activity Recommended Mitigative/Remedial Measure Net Effect Construction
Soil erosion • Adherence to Erosion and Sediment Control Negligible Plan. effect
Incidental spills of • Adherence to Spills Emergency Preparedness Negligible oil, gasoline and and Response Plan. effect other liquids during construction
Hazardous • Adherence to Hazardous Materials Negligible Materials/ Waste Management Plan and Waste Management effect Plan. • Waste disposal in accordance with regulatory requirements.
Blasting • Adherence to DFO guidelines (Wright and Negligible Hopky, 1998) and blasting engineer effect recommendations.
In-water • Use of clean rock fill for cofferdam. Negligible construction • Placement of rock fill over similar coarse effect activities substrate. • Judicious selection of discharge location and water pressure during dewatering. • Adherence to in-water construction timing restrictions. • Confined upland disposal of dredged material.
Operation
Incidental spills of • Adherence to Spills Emergency Preparedness Negligible oil, gasoline and and Response Plan. effect other liquids during operation
Final 4-31 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
4.4 AIR/NOISE EFFECTS
4.4.1 Noise
The Proposed Undertaking is a potential source of local noise during the construction phase. All work is expected to be completed using conventional construction methods. The noise associated with this phase of the proposed project would most likely be a result of activities such as site grading, site preparation and foundation work. All of these activities, which are expected to take approximately 18 months, will require the use of various pieces of heavy equipment including bulldozers, front-end loaders, small trucks, backhoes, bobcats, dump trucks, compactors, ready-mix concrete trucks and cranes. Other construction activities, such as those related to the placement of the facility components (e.g., generator) and activities inside the building (once built) are expected to generate less noise. The movement of worker vehicles will also result in minor increase in the background sound levels during the 24 months construction period. The Proposed Undertaking will be constructed using standard construction best management practices and therefore, no unusual construction noise effects are anticipated.
The addition of noise to an environment can be an impact to people, in particular more sensitive receptors that may live in close proximity to the origins of noise. Noise assessments are typically done in areas where people live, work and/or play. However, the Proposed Undertaking is located in a remote wilderness area with no permanent homes or camps. A couple cottages are located approximately one kilometre from the proposed GS.
Noise exposure will be confined to the limited times that these individuals travel near the site and noise may not even be audible depending on the construction stage or time of day.
During the operation stage of the proposed GS the noise conditions will return to the existing situation. Typically, the noise effects of hydroelectric generating stations are barely audible as the equipment is housed in the powerhouse and the sound of water spilling through the dam masks any sound that may emanate from the generating station.
4.4.2 Air
Air emissions which are associated with construction activities are primarily dust and typical combustion emissions from construction equipment such as carbon monoxide, nitrogen oxides and sulphur dioxide. As with any construction site, these emissions will be of relatively short duration and unlikely to have any adverse effect on the surrounding areas.
A variety of best practices with respect to the control of air emissions have been identified and should be implemented on the construction site (e.g., Cheminfo, 2005). The best practices should include: plans to minimize dust generation through planning, site layout and the proper use of materials, tools and equipment; use of wind fencing; compacting disturbed soil; activity
Final 4-32 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station scheduling; storage piles management; minimization of drop heights; barriers to prevent dispersion of materials; avoidance of blasting where feasible; work practices for loading debris; avoidance of prolonged storage of debris; and proper techniques for the use of materials that include VOCs.
To reduce particulate emissions, effective dust suppression techniques, such as on-site watering and limiting the speed of vehicles travelling on the roads, will be used. During construction the practices and procedures outlined in the document “Best Practices for the Reduction of Air Emissions from Construction and Demolition Activities (March, 2005)” prepared by ChemInfo Services Inc. in conjunction with Construction & Demolition Multi-Stakeholders Working Group for Environment Canada should generally be followed. Some of key best practices, prepared by ChemInfo Services Inc., for the reduction of air emissions during the demolition and construction phases of the undertaking are summarized below:
• Plan to Minimize Dust Generation – Site planning should be conducted in order to maximize construction efficiency and consequently minimize emissions. Some key planning considerations include: o Design proper site layout - Location of stockpiles, access road(s), etc. should be such that the potential generation of fugitive dust is minimized. Prevailing wind direction should be considered when designing the site layout; o Develop dust management plan (as part of the environmental management plan) – identify potential fugitive emission sources during the construction phase; and, o Assess materials/tools/equipment to be used/handled - Decisions can then be made with respect to appropriate materials/tools/equipment that will serve to minimize dust generation (ChemInfo, 2005). • Use wind fencing – Wind fence should be used at the permanent perimeter or temporary interior fencing of the construction site, early in the construction phase. Examples of wind fencing include: trees or shrubs left in place during site clearing; sheets of plywood; wind-screen material such as that used around tennis courts; snow fences; hay bales; crate walls; sediment walls; burlap fences; etc. Block walls, if part of the final project, can replace wind fencing during the site construction phase (ChemInfo, 2005). • Compact disturbed soil – disturbed soil may be compacted with rollers or other similar equipment in order to reduce the erosion potential of the area (ChemInfo, 2005). • Activity scheduling – Where feasible, reduce certain dust generating activities during periods of high wind speeds. Construction operations that generate greater levels of dust may be avoided or reduced. Instead, these activities can be conducted when more favourable weather conditions occur (ChemInfo, 2005). • Storage Piles Management – Several work practices can be employed to mitigate fugitive dust emissions resulting from storage piles. These work practices, which primarily reduce the exposure of storage piles to wind, include: o Activities pertaining to the storage piles, such as loading and unloading, material drop, etc. should be confined to the downwind side of the storage piles. Also, the storage piles should also be located away from downwind site boundaries.
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o Use partial or full enclosures or covers for the storage piles, depending on usage frequency. Examples of enclosures used for reducing fugitive dust emissions from storage piles include: three-sided bunkers that are at least as high as the stockpiled materials, storage silos for materials such as bulk cement, bentonite and similar fine dry materials. Tarpaulins, plastic, or other material can also be used as a temporary covering. Small or short-term inactive storage piles should be enclosed or kept under sheeting while larger inactive storage piles should be shrouded, capped or grassed over. o Utilize wind fences/screens for storage piles porous wind fences/screens provide an area of reduced wind velocity that reduces wind erosion potential and fugitive dust emissions from the exposed surface on the leeward side of the fence/screen. A vertically-abrupt barrier will provide large reductions in velocity for relatively short leeward distances, whereas porous barriers provide smaller reductions in velocity but for more extended distances. o Properly shape storage piles storage piles should be maintained so that they do not have steep sides or faces. In addition, sharp changes of shape in the final storage pile should be avoided. The disturbance of storage piles should also be minimized where feasible. o Material delivery should be properly scheduled in order to minimize storage time and thus fugitive dust emissions (ChemInfo, 2005). • Minimize drop heights – Where possible, reduce the drop height of materials in order to minimized emissions associated with material drop. To minimize dust generated during the material drop process, the debris can be dropped over several sequential stages instead of the entire distance at once (ChemInfo, 2005). • Barriers to Prevent Dispersion – Enclosures, curtains or shrouds can be utilized during the demolition phase to confine dust generation. Enclosures, curtains or shrouds may be impractical during demolition activities lasting a few days or less. Prior to blasting, buildings should be screened with suitable debris screens and sheets (ChemInfo, 2005). • Avoid Blasting When Feasible – Blasting with explosives has the potential to generate large amounts of fugitive dust emissions in a very short period of time. Blasting should be avoided and other demolition and deconstruction methods used wherever possible. It is noted that in some instances, blasting is the safest manner in which to quickly bring down a structure. Blasting operations can significantly reduce the size of the building and its component materials. The generation of a large amount of fugitive dust in the short term through blasting may reduce the potential for prolonged periods of fugitive dust emissions that would otherwise occur in ongoing size reduction operations (ChemInfo, 2005). • Work Practices for Loading Debris – Loaders should tip debris into haulage trucks with a minimum fall distance to minimize dust emissions from tumbling debris. If possible, fine debris should be placed into the truck bin first, followed by larger debris on top. Alternatively, if possible, dry debris should be placed into the truck bin first, followed by wet debris on top. Debris loads should be balanced in truck bins. Debris loads should not be compacted using the impact of a loader bucket (ChemInfo, 2005).
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• Avoid Prolonged Storage of Debris – Avoid prolonged storage of debris on site and its exposure to wind. Waste and refuse bins should be covered when they are being removed from the construction site (ChemInfo, 2005).
Other emissions associated with construction activities include Volatile Organic Compounds (VOCs) emitted during surface coating operations. Architectural surface coating operations consist of applying a thin layer of coating such as paint, paint primer, varnish or lacquer to architectural surfaces. Surface coatings are applied to a variety of surfaces including, metal, wood, plastic, concrete, bricks and plaster. VOCs that are used as solvents in coatings are emitted during the application of the coating as well as when the coating dries. The amount of coating used and the VOC content of the coating are the primary factors that determine emissions from this source. Solvents are also used as thinners in the coatings and for cleanup activities. Some of the ways of reduces the VOC emissions include:
• Use durable and high performance coatings with a low VOC content; • Minimize VOC emissions from the storage, handling and preparation of coatings; • Minimize coatings wastage through spillage and splashing; • Properly prepared the surface to be coated, prior to coating; • Where possible, paint heaters should be used instead of paint thinners; • Technologically advanced spray-guns should be utilized to apply coatings; • Spray-gun operators should apply correct application techniques; • Proper technique should be used when cleaning spray guns; • Alternative coating application techniques should be used; • Use alternative cleaners or low-VOC cleaners; • Minimize the amount of solvents used for cleaning; and, • Where possible, alternative finishing practices should be used (ChemInfo, 2005).
For more details regarding the above methods of reducing emissions during the demolition and construction phase, please refer to the ChemInfo document: “Best Practices for the Reduction of Air Emissions from Construction and Demolition Activities (March, 2005).”
It is anticipated that the net effects on the local air quality during construction phase of the proposed undertaking would be negligible and thus no other mitigative measures are required.
During the operation stage of the project, air quality will return to the existing situation. There are no air emissions associated with the hydroelectric generating station except for the very use of backup generators to re-start equipment.
Final 4-35 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
4.5 SOCIO-ECONOMIC ENVIRONMENT EFFECTS
4.5.1 Demographics, Community and Economics
The Proposed Undertaking will have a positive economic impact on the Province, Northeastern Ontario and locally in Timmins and Gogama. The economic impact of the Proposed Undertaking was assessed using the Lake Abitibi Model Forest Community Constellation Impact Model.
It is estimated that expenditure in the range of $7M to $9M7 will be made in the Timmins and Northeastern Ontario economy. This initial expenditure will primarily occur in the non-residential construction sector but also in other business and engineering services. The expenditure will result in the following economic impacts within Timmins and Northeastern Ontario: for every dollar of expenditure associated with the project a total of $1.50 in sales will occur in Timmins (sales multiplier of 1.50); total wages and salaries8 of $4- $6M; 75 (46 direct and 29 indirect and induced) – 99 (60 direct and 39 indirect and induced) person years of permanent full-time job equivalents; and, for every one job associated with the initial expenditure 0.65 jobs are supported in the economy at large.
The total tax benefits to government are significant. It is estimated that just the expenditure in Northeastern Ontario could produce $3M to $4M in taxes. This also does not include the benefit to the Province of Ontario from the Gross Revenue Charges (CRC) associated with the Project or the electrical generation.
Beyond the impact within Gogama, Timmins and Northeastern Ontario this project is anticipated to result in a larger expenditure throughout Ontario with a positive economic impact as well.
The economic impacts of construction projects can have associated positive and negative social impacts (e.g., increased demand for social services) in local communities. However, given that: Timmins is a large established economic centre; the City has a broad range of social services; economic opportunities in the north are critical to maintenance of the region’s population base; and that large construction projects are a common occurrence in Timmins, it is likely that the vast majority of impacts will be positive for the community and region.
It should also be noted that the Proposed Undertaking will likely have significant positive economic benefits for Mattagami First Nation. While the nature of those benefits are currently being discussed in confidential negotiations between Mattagami First Nation and OPG, the parties will be entering into a commercial arrangement for the project.
The proposed GS will be operated remotely from OPG’s Northeast Plant Group offices in Timmins and there will be no permanent staff at the facility. However, OPG staff will be required
7 All economic output values have been rounded to $1M.
Final 4-36 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station to undertake periodic maintenance activities. As such, it may have a positive effect on employment levels.
As well, some maintenance will be required on the transmission line. It is possible that Mattagami First Nation may be interested in clearing the transmission corridor and managing vegetation control associated with the line on an on-going basis.
4.5.2 Land-Use Planning, Access and Transportation
Based on a review of all the relevant Crown land use area policies, the Proposed Undertaking and its ancillary activities are permitted and wholly consistent with the existing land use direction for the area and the provincial policy statement.
Access to the proposed GS is via Kenogamissi Falls Road. The proposed Generating Station does not require the road to be altered. A parking lot will be required for the powerhouse off the north side of Kenogamissi Falls Road about 50 meters west of the bridge. The location of the parking lot would be shown on the final drawings submitted by OPG’s contractor to MNR for approval of a work permit under the Lakes and Rivers Improvements Act (LRIA). As the road is subject to logging operations appropriate signage is recommended.
OPG has already conducted discussions with Tembec which owns the Kenogamissi Falls Bridge. OPG will require the contractor to meet with Tembec to discuss any issues with respect to structural concerns or timing associated with construction.
Kenogamissi Falls Road is the only access road for resource users and members of the public utilizing parts or all of Hassard, Beem, Gouin, Moher, Emerald and Nursey Townships (or area between Grassy and Mattagami Rivers). During construction of the proposed GS the penstock will need to be placed below the surface of Kenogamissi Falls Road. It is estimated that this construction may require the road to be closed for one week. If possible the penstock will be constructed in stages so the road does not need to be fully closed. If the road needs to be closed for construction, OPG will require the contractor to negotiate the time of the year for this to occur with all permitted resource users in this area (trappers, baitfish operator, BMA operators, outfitters, prospectors, Hydro One and Tembec) and the MNR Timmins District Local Citizens Committee. Once a time has been agreed to the contractor will advertise the road closing in both English and French newspapers that service both Timmins and Gogama; notify Mattagami First Nation; and, post signage on Kenogamissi Dam Road indicating the dates of the closure at least one month prior to the first day of closing.
With respect to traffic, the operation of the proposed GS will be remotely controlled in Timmins and permanent staffing will not be required. However, OPG staff will periodically visit the station to undertake maintenance, minor repairs and tests. It is anticipated that there will be only a couple trips to the proposed GS per week and therefore the incremental traffic on an already lightly used road will be insignificant.
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Tembec also indicated to OPG that the transmission line should be high enough to provide adequate clearance for equipment whose maximum height would be about 20’. They indicated that the Ministry of Transportation Ontario highway clearance specifications would be more than adequate to resolve this issue.
During construction it is estimated that there will be 40 – 50 workers commuting to the site on a daily basis along with the periodic arrival of equipment and materials. The incremental traffic impact on the already lightly travelled Kenogamissi Falls Road will not have a significant impact.
It would be expected that the contractor for the construction of the GS would evaluate the condition of Kenogamissi Falls Road from Highway 144 to the bridge prior to commencing construction and bring the road back to a similar condition on completion of the project.
All roads will have a half load restriction mid-April to 1st of June.
Because there is an existing dam and boom line already in place and approved by Transport Canada under the Navigable Waters Protection Act and the proposed undertaking is a minor undertaking and will not limit or prevent boating, no approval is required from Transport Canada. OPG will have regard for Transport Canada’s considerations for Portage Crossing a Road in design of the final facility.
4.5.3 Resource Use
A forest resources impact assessment was carried out for the various transmission route alternatives. The data shows that there is little difference in the four alternatives in terms of forest areas affected with respect to area or merchantable timber (72.5 to 74.3 cubic metres). Most of the area affected is younger regenerating conifer plantations or naturally regenerated hardwoods and mixedwoods. There is a small amount of mature mixed wood impacted mainly at the western end of the proposed transmission line.
There is only 1.6 hectares of mature Mw3 (poplar, birch and spruce mixedwood) stands affected as all of the remaining areas are natural regenerations or plantations. The total volume impacted is estimated to be only 74 cubic metres including 30 cubic metres of black and white spruce, 10 cubic metres of cedar, 19 cubic metres of poplar and 16 cubic metres of white birch.
A small forest resource license would be required from MNR to harvest the timber from the selected route. Stumpage fees would be due to the Crown on the 74 cubic metres of merchantable volume. There is not enough volume to be easily marketable, particularly given its locations farther from the mills therefore on other option may be to provide the entire volume to Mattagami First Nation as fuelwood if that was considered acceptable to MNR. Having Mattagami First Nation harvest the site would also enable this.
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There are no mineral claims at either the site of the proposed GS or the proposed transmission corridor and therefore there is no impact. The one mineral claim, #4217582 occurs east of the Hydro One 115 kV line and which requires access via Kenogamissi Falls Road. The only impact on this claim would be the temporary closure of access on Kenogamissi Falls Road previously discussed. The mineral claim holder will also need to be notified of the road closure.
The Proposed Undertaking is not expected to have any impacts on cottages near the local study area.
The main recreational activity in the immediate area is angling, which occurs on the west bank of the river, immediately north of the bridge. The powerhouse is proposed to be located in this same area. The powerhouse is not predicted to impact on the existence of fish in this location, as the tailraces of powerhouses are often good locations for fish. However, to ensure public safety access will be restricted to the public around the powerhouse and downstream. OPG will be implementing a combination of signage, buoys, fencing and/or booms to restrict public access.
Final 4-39 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Figure 4.14 Portage and Restriction of Public Access
As the economic impact of non-remote angling (non-outfitted) in the north is driven by demand and not by supply there will be no negative economic impact. A negative social impact will occur as some anglers who prefer this location will need to re-locate to other spots.
The proposed GS will not affect recreational canoeing or boating use in the area.
As the proposed GS is located within 100 metres of Kenogamissi Falls Road and since hunters are discouraged from hunting in locations where other people may be present, no effect on hunting is expected.
A bear stand is located within 100 metres of the proposed transmission corridor. Except during construction, the transmission line would not impact hunting operations.
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Because of the area’s importance as a hunting area it is important that construction workers will not degrade the experience of other users. Therefore, it is recommended that contractors and employees of the contractor be restricted from fishing and hunting at the site during the duration of the construction period. As well, overnight trailers and stays by workers will not be permitted.
The small amount of forest clearing required for the Proposed Undertaking is not expected to have any significant effect on furbearer populations and therefore no economic effect on trappers.
As trappers who hold trapline numbers east of the Proposed Undertaking use the Kenogamissi Falls Road for access to their traplines and it is likely at some point during the construction that the road will need to be closed to allow the construction of the penstock beneath the road it is important that the contractor properly notify trappers. This mitigation measure is discussed in more detail in section 4.4.2, Access and Transportation of the Socio-Economic and Land Use TSD.
The proposed GS will not displace or disrupt any snowmobile trails in the region. The proposed transmission line would bisect the existing Moher Lake Road which doubles a snowmobile trail, but this would not have any impact on snowmobile activity on the trail. In fact, it is likely the addition of the transmission line will add another potential corridor for snowmobile travel. Whether an official trail would be located in this corridor would depend on discussions among the OFSC, OPG and MNR.
As Crown land camping does not occur at the site of the proposed GS or along the transmission corridor, there will be no effect on this activity.
4.6 CULTURAL RESOURCES IMPACTS
The impact and mitigation of the proposed GS on cultural resources are being addressed in accordance with the requirements of the Ministry of Culture and the Ontario Heritage Act, with the participation and the co-operation of the Mattagami First Nation.
The old or historic utility line was also assessed as part of a Stage 1 & 2 Cultural Heritage Assessment of the Proposed Undertaking. Surface inspections and sub-surface testing of this line was negative and no cultural resources were identified (Woodland Heritage Services Limited, 2008).
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4.7 EFFECTS ON FIRST NATIONS AND ABORIGINAL PEOPLES
Taking into account the implementation of mitigation and monitoring measures proposed, the Proposed Undertaking is not likely to cause any significant adverse environmental effects. No impacts to Aboriginal traditional rights were identified during the consultation process.
The Métis Nation of Ontario was also consulted on the Proposed Undertaking and raised three concerns which have all been resolved through mitigation measures. First, the MNO were concerned about the temporary road closure on Kenogamissi Falls and that they might potentially have harvesters trapped behind the closure. OPG has committed to co-operating with the MNO in notifying Métis members about the closing at the appropriate time. Second, the MNO indicated that they were opposed to the use of herbicides for vegetation suppression on transmission lines. OPG indicated that they are committed to keeping the vegetation down along the transmission corridor through mechanical rather than chemical means. Third, the MNO indicated that they would like to visit the site during construction and be made aware of what efforts are made during construction to protect the environment. MFN and OPG agreed that the MNO would be invited to the site a couple times during construction to view activities. OPG indicated that this request should be made through MFN.
Final 4-42 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
5.0 PUBLIC AND AGENCY CONSULTATION
5.1 CONSULTATION WITH PUBLIC
5.1.1 Objectives and Approach
The objective of the public consultation program for the Proposed Undertaking was “to provide the public with an opportunity to have meaningful input on the project and address public concerns where possible and feasible.” The key components of the public consultation program included: two open houses/public meetings; two project newsletters; a project website; ongoing public inquiries; and, an issue tracking system. All of these components have been implemented as planned. A Public and Agency Consultation Technical Support Document has been prepared on the project and provides in more detail a summary of the overall public consultation program.
5.1.2 Summary of Activities
A database of stakeholders who were to be notified about the Proposed Undertaking and the key consultation opportunities was developed based on OPG, consultation and agency knowledge. A total of 120 stakeholders were on the list at the time of the mailing for the second open house.
The first public open house with respect to the Proposed Undertaking was held on June 21, 2007. The agenda included an open house followed by a formal presentation and questions and answers period. A total of 14 individuals attended the Open House, of which most attended the presentation.
A second set of public open houses with respect to the Proposed Undertaking were held in Gogama on November 20, 2007 and in Timmins November 22, 2007. The agenda included an open house followed by a formal presentation and questions and answers period. A total of 51 individuals attended the Open House.
A web site about the project was set up and can be found at www.mattagamilakedam-ea.com. The website provided a project description, some FAQs, a description of the EA process, notifications about public meetings and contact information. This website was active by early June 2007. Phone numbers and e-mail addresses to the OPG Project Manager and the SENES environmental assessment co-ordinator have been available throughout the course of the project on the internet site, albeit these have only been very lightly used by the public.
Final 5-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
5.1.3 Public Issues and Concerns
The public and agency consultation process for the Proposed Undertaking has been comprehensive and inclusive of all interested individuals and government representatives. Throughout the course of the project there has not been a single individual indicating any opposition to the Proposed Undertaking. A fuller description of the public consultation process and comments made by the public can be found in the Public and Agency Consultation Technical Support Document.
5.2 CONSULTATION WITH GOVERNMENT AND AGENCIES
5.2.1 Objectives and Approach
The overall objective of the agency consultation was to keep the various federal, provincial and municipal authorities informed of the project and offer to meet with them whenever necessary to discuss and resolve question early in the process.
5.2.2 Summary of Activities
OPG has consulted with various municipal, provincial and federal government agencies throughout the environmental assessment process. Outlined below are the key consultation events.
• November 21, 2006. Meeting with the Ministry of Natural Resources and Department of Fisheries and Oceans at Mattagami Lake Dam site and the Mattagami First Nation Reserve. • February 23, 2007. Meeting with MNR and DFO to discuss fisheries studies especially whitefish. This included the presentation of modeling results. • June 19, 2007 Meeting with Tembec to provide them with an overview of the Proposed Undertaking, and advise them of the Notice of Commencement. • August 8, 2007. Meeting with MNR at the site to answer questions regarding the proposed geotechnical work. • October 18, 2007. Meeting with Ministries of Natural Resources, Culture and Environment. Representatives also in attendance from Department of Transport and Fisheries and Oceans. • November 13, 2007. Meeting with Ontario Ministry of Natural Resources and Department of Fisheries and Oceans. • December 4, 2007. Meeting with Ontario Ministry of Natural Resources and Department of Fisheries and Oceans. • December 17, 2007. Meeting with the Ministry of Natural Resources on the proposed summer flow regime for the generating station. • January 17, 2008. Meeting with the Ministry of Natural Resources on the proposed summer flow regime for the generating station.
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• January 29, 2008. Meeting with the Ministry of Natural Resources on the proposed summer flow regime for the generating station. • April 30, 2008. Meeting with Ministry of Natural Resources on the proposed dam safety work. • March 27, 2009. Meeting with Métis Nation of Ontario to review the project and outline the EA process and results (MOE attended). • July 23, 2009. Meeting with MNR to discuss ecological flow requirements for whitefish. • March 3, 2010. Meeting with MNR to finalize ecological flow requirements for whitefish and walleye. Also resolved outstanding questions with respect to a bedrock pool between the dam and the Bailey bridge. • May 5, 2010. Meeting with Ministry of Culture to provide an update on the EA and discuss cultural heritage aspects of the Proposed Undertaking.
In addition to the formal meetings noted above, OPG has met with and has ongoing communications with Ministry of the Environment file coordinator, Ministry of Culture and Ministry of Natural Resources throughout the EA process.
5.2.3 Agency Issues and Concerns
In the various meetings, held with federal, provincial and municipal representatives, agency representatives spoke with respect to their mandates and responsibilities and what studies or work they might want to see.
An extensive four-year long discussion was held with MNR and DFO on the topic of ecological flow while the proposed GS is not in operation and a rock pool immediately downstream of the dam. That discussion and the results are summarized below. This section also highlights the amendment of the Mattagami River System Water Management Plan (MRSWMP) and amendment process required for the facility.
Based on the consultation that has occurred OPG and SENES do not think there are any outstanding issues or concerns that have not been addressed in the EA.
5.3 DISCUSSIONS WITH MNR AND DFO ON ECOLOGICAL FLOW AND BEDROCK POOL
5.3.1 Introduction
The following summarizes the agency consultation on the topic of “Ecological Flow”. Further information is available in the Aquatic TSD.
The proposed GS will be operated within the parameters and obligations that are stipulated in the amended MRSWMP (OPG et al, 2006). For most of a typical year, this will result in little substantive change between pre-operational flows and post-operational flows downstream of the proposed powerhouse to Kenogamissi Lake. This will almost always be the case during fall,
Final 5-3 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station winter and early spring when river flow is sufficient to operate the proposed GS, and during the walleye spawning and incubation period in mid to late spring when a minimum flow of 12- 15 cubic metres per second (cms) is required. However, in addition to shutdowns for repairs or other technical issues, the GS must be shut down when there is insufficient water storage to allow the generating unit to operate at 20% of its rated capacity. This would occur when the reservoir’s storage capacity is low and inflows are less than 10 cms (assuming a station flow capacity of 47 cms).
When the unit is not operating, a minimum 2.8cms flow (called “Ecological Flow”) as agreed to with the MNR and the DFO will be released for the duration of the year outside of the walleye spawning, incubation, hatch and dispersal period, to maintain the fish habitat in the 550 meters long river section between the tailrace of the new station and Kenogamissi Lake. The agreed- upon flow requirement balances the net economic, social and environmental benefits of the proposed hydropower development at this site.
To maintain the viability of fish habitat in a “bedrock pool” located 40 meters upstream of the bridge, an ecological flow of 0.2 cms must be provided to maintain water quality as well as a maximum water depth of 11 centimetres at the outlet of the pool (Transect S-3). This will provide habitat connectivity with downstream aquatic habitats. To simplify compliance measurement and reporting, the minimum water level in the bedrock pool that corresponds with these conditions will be maintained and measured by OPG. OPG staff will periodically measure the outlet depth by other means to ensure that the maximum depth of 11 cm is maintained at Transect S-3. This is discussed in greater detail in the Aquatic Technical Support Document.
OPG is committed to measuring and monitoring the functionality of the bedrock pool, and the ecological flow downstream of the proposed GS noted above. As part of the final design of the proposed GS, there will be an arrangement for providing the minimum flow other than leakage from the dam.
OPG has also committed to undertaking an effectiveness monitoring program pre and post construction that is discussed in the Aquatic Technical Support Document. The Monitoring Plan will identify any environmental issues that may arise through the use of 2.8 cms as the minimum flow. It will also address the functionality of the bedrock pool. OPG is committed to addressing any potential issues that are identified.
Total construction is expected to take about three years after the award of the construction contract.
5.3.2 Mattagami River System Water Management Plan
The following section describes the existing MRSWMP and operating regime, the operating regime of the new facility; the proposed MRSWMP amendment and summary of changes; description of the amendment process; and, OPG’s request for a minor amendment.
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5.3.3 Existing Water Management Plan and Operating Regime
In 2000, the Ontario Lakes and Rivers Improvement Act (LRIA) was amended to establish the authority of the MNR to order the preparation of Water Management Plans for operation of waterpower facilities and associated control structures and to ensure the facilities being operated in compliance with the Plans. On 14 May 2002, the Water Management Planning Guidelines for Waterpower were approved by the MNR. The intent of the Water Management Plan is to provide certainty and clarity as to how waterpower facilities and control structures are operated with respect to levels and flows so as to achieve environmental, social and economic objectives.
The Water Management Plan for the Mattagami River System was prepared in accordance with the Water Management Planning Guidelines for Waterpower (MNR, 2002) and covered 18 waterpower facilities and associated structures located along the Mattagami River that have influence on levels and flows (OPG et al., 2006). The Plan was the result of a partnership among OPG, the MNR and other private power producers who operate facilities along the river as well as First Nations and the general public, who participated in the form of various advisory committees.
All the facilities and associated structures along the Mattagami River shall be operated in compliance with the operating regimes established in the Water Management Plan for the Mattagami River System. A compliance monitoring program has been established and enforced by MNR for the Mattagami River.
The Mattagami River System has an approved Water Management Plan. Based on historical hydrological data, the greatest stream flow occurs during the spring freshet in April, May and June with the lowest flows occurring generally during the summer as shown in Figure 5.1.
Final 5-5 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Figure 5.1 Monthly Average Flows Released from Mattagami Lake Control Dam (1950-2006)
Figure 5.2 Mattagami Lake Dam Historical Operating Graph Mattagami Lake - Elevation (1950 - 2003)
332.50
331.50
330.50
329.50
328.50 Elevation (metre)
327.50
326.50
325.50 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 Week
25% 50% 75% Op. Min. Abs. Max Abs. Min.
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Existing Operating Regime
The existing operating regime for the Mattagami Lake Dam is as follows.
Operating Range: 326.20 – 331.48 m Absolute Range: 326.20 – 331.48 m Summer Band: 330.90 – 331.48 m Victoria Day weekend to Sept 1 Winter Drawdown: Winter drawdown to 326.64 m prior to freshet Flood Allowance: None Energy Emergency: None Maximum Discharge: None Minimum Discharge Winter: 30 cms in the winter months – In effect when elevation is above 330.70 m to limit ice formation against the dam. Minimum Natural Flow regime: Low Flow – N/A Bankfull Flow– N/A Riparian Flow – N/A Fisheries Constraint: 12-15 cms during walleye spawning and incubation when water temp reaches 5 0C. The minimum flow implemented for walleye spawning at MLD might vary between 12-15 cms from year to year, depending on the observed and anticipated flow conditions each year, as per the current MRSWMP (2006). Other: Educate the Public – WMP consultation program (scoping, options, and Draft Plan stages), Public Waterway Safety, and Cottage Association meetings. OPGI website www.OPGI.com/envcomm/wateruse/riversystems.asp OPGI phone 1-705-268-9197.
The normal operating water level range for the Mattagami Lake is 326.20 to 331.48 metres. From the Victoria Day weekend to September 1st, the water level is maintained between 330.90 metres and 331.48 metres for recreational and navigational purposes. Mattagami Lake has no flood allowance.
For dam safety purposes, a minimum flow of 30 cms is maintained during the winter period when the water level is 330.70 metres or higher in order to prevent significant ice load against the dam.
For fisheries, when the water temperature reaches 5 ºC in the spring a minimum flow of 12-15 cms is maintained during walleye spawning and incubation. The MNR is required to notify OPG when the walleye are gathering in the pool below the dam.
Final 5-7 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
5.3.4 Operating Regime of New Facility
The new facility will be operated remotely and maintained by OPG’s Northeast Plant Group staff located in Timmins, Ontario. The remote control will facilitate faster response to changing conditions in the Mattagami Lake Watershed. The proposed GS along with the new sluice gate at existing sluice #3 will be remotely operated for quick control of the water levels under conditions of high reservoir water elevation, rising water levels and inflows exceeding station capacity. Depending on storage reservoir elevations, unit availability and forecasted inflow conditions, log operations will continue following the construction of the proposed GS.
The proposed GS will continue to operate with no appreciable change to monthly average flows and water elevations. The storage reservoir, based on inflow forecasting, will be regulated to maintain minimum flows and water elevations within approved operating limits. The operations will also maximize the efficient use of water resources.
Proposed Operating Regime with New Generating Station
Operating Range: 326.20 – 331.48 m Absolute Range: 326.20 – 331.48 m Summer Band: 330.90 – 331.48 m Victoria Day weekend to Sept 1 Winter Drawdown: Winter drawdown to 326.64 m prior to freshet Flood Allowance: None Energy Emergency: None Maximum Discharge: None Minimum Discharge Winter: None Minimum Discharge 2.8 cms flow downstream of the powerhouse for the duration of the year outside of the walleye spawning, incubation, hatch and dispersal period. A minimum flow of 0.2cms will be provided upstream of the powerhouse to ensure the functionality of the bedrock pool located 40 m upstream of the bridge. Natural Flow regime: Low Flow – N/A Bankfull Flow– N/A Riparian Flow – N/A Fisheries Constraint: 12-15 cms during walleye spawning and incubation when water temp reaches 50C. Other: Educate the Public – WMP consultation program (scoping, options, and Draft Plan stages), Public Waterway Safety, and Cottage Association meetings. OPG website www.OPGI.com/envcomm/wateruse/riversystems.asp, OPGI phone 1-705-268-9197.
Final 5-8 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
5.3.5 Summary of Changes to the Existing Water Management Plan
With the exception of two (2) revisions noted below, the constraints of the existing operating regime will remain the same. The normal operating water level range for the Mattagami Lake will be maintained between 326.20 to 331.48 metres as in the existing operating regime. From Victoria Day weekend to the September 1st the water level for the Mattagami Lake will be maintained between 330.90 and 331.48 metres for recreational and navigational purposes.
For fisheries, when the water temperature reaches 5 ºC in spring a minimum flow of 12 cms will be maintained during walleye spawning and incubation. The MNR will be required to notify OPG when the walleye are gathering in the tailrace pool below the dam.
The Proposed Undertaking will follow the existing Operating Regime as currently defined in the Approved Water Management Plan with the following modifications:
The two changes to the existing Operating regime are summarized below. a) New Constraint
As agreed between MNR and OPG, there will be a new requirement relevant to operation of the proposed GS.
A 2.8 cms flow (called “Ecological Flow”) will be released for the duration of the year outside of the walleye spawning, incubation, hatch and dispersal period, to maintain the fish habitat in the 550 m-long river section between the tailrace and Kenogamissi Lake when the unit is not operating. The 2.8 cms includes a flow of 0.2 cms that will be provided upstream of the tailrace to maintain the fish habitat in the “bedrock pool” located 40 m upstream of the bridge. b) Change of Constraint
The existing dam will be rehabilitated by installing post-tensioned rock anchors and repairing the deteriorated downstream surface to enhance its stability in accordance with Ontario Dam Safety Guideline (1999). The rehabilitation may be executed prior to the construction of, or as part of the Proposed Undertaking. After the rehabilitation, the dam can take the full ice load, therefore the winter operating restriction will not be needed (i.e., maintaining a minimum flow of 30 cms will not be required during the winter period when the water level is 330.70 metres or higher in order to prevent significant ice load against the dam). The dam will continue to be operated to meet the requirement of winter drawdown to 326.64 m prior to freshet.
The existing approved MRSWMP section 1.2 indicates that the Goal of the Water Management Plan is:
Final 5-9 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
…to contribute to the environmental, social and economic well-being of the people of Ontario through the sustainable development and use of waterpower resources and to manage these resources in an ecologically sustainable way for the benefit of present and future generations.
The Proposed Undertaking does not change the Goal of the Water Management Plan.
The existing approved MRSWMP Section 1.3 identifies the following Water Management Planning Objectives:
1. To review the existing operational plans and to develop an overall Water Management Plan for the Mattagami River system with specific operational plans for each generating station and water control structure. 2. To identify issues and concerns regarding management of dam and hydroelectric facilities associated with eh Mattagami River and develop strategies to address these. 3. To establish a process for on-going monitoring of WMP compliance and amendments to the plan if necessary.
The Proposed Undertaking does not change the existing Water Management Plan Objectives noted above.
The existing approved MRSWMP Section 1.4 identifies the following specific Mattagami River Water Management Planning Objectives:
Fisheries: Maintain or improve fisheries health through the river system. Navigation: Maintain or improve navigability throughout the river system. Recreation: Maintain or improve recreational opportunities throughout the river system. Flooding: Minimize the risk of damage due to flooding throughout the river system. First Nations: Maintain or improve protection of known First Nation values and traditional relationship throughout the river system. Cultural Heritage: Maintain or improve protection of known cultural heritage values throughout the river system. Erosion: Minimize the impacts of erosion caused by facility operation throughout the river system. Wildlife Maintain or improve wildlife habitat throughout the river system. Economics Maintain or improve sustainable economic opportunities throughout the river system. Public Safety: Maximize public safety throughout the river system. Power Generation: Maintain or improve power production throughout the river system.
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Natural Flow Regime: Maintain or improve water levels and flow to more closely match the natural flow regime of the river. The Natural flow regime is used as a guide to determine water levels and flows that best protect and enhance the aquatic ecosystem.
The Proposed Undertaking does not change the Mattagami River Water Management Planning Objectives identified above. The new Operating Regime for the Proposed Undertaking will be presented to the Standing Advisory Committee for their review and comment.
5.3.6 The Amendment Process
Amendment Request:
Any request for an amendment must be accompanied by sufficient information to allow the MNR Regional Director to determine whether the proposed amendment should proceed, and whether the amendment should be treated as administrative, minor of major. The amendment request must contain the following information:
• A brief description of the proposed amendment. • The rationale for the proposed amendment and a discussion of its significance. • If new operations are proposed: a) A brief description of the proposed operation and a description of the previously approved operations in the WMP that will be changed by the proposed amendment. b) An outline of the applicable planning requirements for the proposed operations including public consultation, based on the planning requirements for similar operations in the WMP.
Final 5-11 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Figure 5.3 The WMP Amendment Process
NEPG1: Northeast Plant Group PGM2: Plant Group Manager MNR-DM3: Ministry of Natural Resources District Manager SAC4: Water Management Plan Standing Advisory Committee MNR-RD5: Ministry of Natural Resources Regional Director
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5.4 REVIEW OF AMENDMENT REQUEST AND CATEGORIZATION OF AMENDMENT
The MNR Regional Director is responsible for determining whether an amendment should proceed and for categorizing the amendment as administrative, minor or major. In making this determination, the MNR Regional Director, in consultation with the plan proponents, will decide on the appropriate degree of public consultation for the plan amendment.
The MNR Regional Director considers the following factors in determining whether to grant the request for an amendment and in determining the appropriate amendment category:
• Whether there are legitimate time constraints that must be met for reasons of public safety, biological or industrial necessity, or public convenience and necessity; • Whether the amendment is justifiable based on public safety, biological or industrial reasons; • Whether there has been previous notification that the requested amendment will be required, and the degree to which planning and public consultation has taken place previously (e.g. decision deferred in the WMP, or an amendment required after public consultation in other planning processes; and, • The number of previous requests for similar amendments.
The decision on the amendment request and on the appropriate category for the amendment will normally be made within 15 days of receipt of the request. The MNR Regional Director will prepare a written decision.
The Standing Advisory Committee will be informed of all amendments and will be given an opportunity to provide comments. The public and First Nations communities will be consulted on any minor and major amendments.
5.4.1 Types of Amendments:
Section 14.2.1.3 of the approved MRSWMP there are three types of amendments permitted:
a) Administrative; b) Minor; and, c) Major. a) Administrative Amendments
According to the approved WMP section 14.2.1.3, administrative amendments are those that “... that will not affect the implementation of the plan (e.g. a change in the presentation of information in the plan) and there are no formal public consultation requirements”. There are no formal First Nations consultation requirements.
Final 5-13 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station b) Minor Amendments
According to this section, “Minor amendments will be changes that are anticipated to affect a small geographic scale (i.e. in the vicinity of one dam) and where MNR and the Steering Committee agree that it will not have significant impact. Public consultation requirements are for a notice of proposed amendment to be issued by MNR. The degree of First Nations consultation will depend on the nature of the amendment but will include notification of local First Nation communities as a minimum”. c) Major Amendment
According to the approved WMP section 14.2.1.3, Major Amendments “….may involve a significant geographical scale or have a significant impact on the balancing of the environmental, social and economic attributes. Public consultation requirements are for an information centre and a notice of proposed major amendment inspections to be issued by MNR. The degree of First Nations consultation will depend on the nature of the amendment but will include notification of local First Nation communities as a minimum.”
5.4.2 OPG - Request for Minor Amendment
OPG will request a minor amendment to the existing MRSWMP to include the two new operating constraints: a minimum flow 2.8 cms for the duration of the year outside of the walleye spawning, incubation, hatch and dispersal period and a minimum flow (0.2 cms) to ensure the functionality of the bedrock pool located 40 m upstream of the bridge; and, removal of the winter ice load flow constraint described above. The new generating station at Mattagami Lake Dam will be operated in compliance with the amended MRSWMP. The amendment will be implemented upon final completion of the proposed GS, the WMP amendment process and OPG completion of Section 16 of LRIA.
Final 5-14 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
6.0 CONSULTATION WITH FIRST NATIONS AND ABORIGINAL PEOPLES
6.1 OBJECTIVES AND APPROACH
During project initiation, the potential impact of the project was anticipated with respect to the Mattagami First Nation. Significant consultation efforts were undertaken with the Mattagami First Nation for the following reasons:
• Based on their close proximity to the proposed site, the ancestors of Mattagami’s current population are likely those who traditionally occupied the lands in this vicinity. • Mattagami First Nation has signed an MOU with OPG to discuss the possibility of entering into a commercial arrangement on the Proposed Undertaking.
With respect to the other First Nations, it was uncertain whether there would be any interest in the project as a result of the long distances from their communities to the project and also owing to the fact that the project was located in very close proximity to Mattagami First Nation and was clearly in their traditional territory. However, given that other First Nations may have an interest in the project, an offer to consult was made to other First Nations.
Described below is a summary of consultation activities with the First Nations and the MNO.
6.1.1 Summary of Activities
An offer to consult was made to all four First Nations identified in the First Nations Consultation Plan. Outlined below is a summary of consultation activities undertaken with the First Nations. At a later date, OPG also offered to consult with the MNO.
6.2 FIRST NATIONS ISSUES AND CONCERNS
6.2.1 Matachewan First Nation
As indicated in the First Nations Consultation Technical Support Document a total of two letters and eight phone calls have been placed to Matachewan First Nation. As there has been no response to date and the Chief of Matachewan was aware of the project, OPG has assumed Matachewan First Nation does not have any issues or concerns.
Furthermore, three calls were placed to Wabun Tribal Council to see if Flying Post, Matachewan or Wahgoshig First Nation were interested in being consulted on the project. A Wabun Tribal Council representative (and member of Matachewan First Nation) called back and indicated that Matachewan did not need to be consulted on the project.
Final 6-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
6.2.2 Flying Post First Nation
Two formal letters were sent via courier by Ontario Power Generation to Flying Post First Nation describing the Proposed Undertaking, together with an offer to consult on the project. As well, five phone calls were made to follow up. This consultation is described in the First Nations Consultation Technical Support Document.
At one point in the process the Chief of Flying Post indicated that he had given responsibility for the project to Wabun Tribal Council. Subsequently, three calls were placed to Wabun Tribal Council to see if Flying Post, Matachewan or Wahgoshig First Nation were interested in being consulted on the project. A Wabun Tribal Council representative called back and indicated that Flying Post may wish to discuss the matter with Mattagami First Nation. Subsequently the Chief of Mattagami First Nation has spoken to the Chief of Flying Post and no issues have been raised.
6.2.3 Wahgoshig First Nation
One formal letter and offer to consult on the project was made to Wahgoshig First Nation. The potential interest of Wahgoshig in the broad study area was not known to OPG until after a meeting with Wabun Tribal Council in the fall of 2007.
Subsequently four follow-up phone calls were made to see if Wahgoshig wished to discuss the project. None of these calls were returned. A representative from Wabun Tribal Council indicated that Flying Post (discussed above) and Mattagami First Nation were the only Wabun communities with an interest in the project.
6.2.4 Métis Nation of Ontario
In the latter part of 2008 and early 2009, OPG held meetings with the Métis Nation of Ontario (MNO) on its Lower Mattagami Hydroelectric Project, north of Kapuskasing. In those meetings, OPG identified its other hydroelectric projects in the region including the Mattagami Lake Dam Project. As a result of those meetings, a meeting was set up with the MNO to specifically discuss the Mattagami Lake Dam Project. Outlined below is the sequence of meetings, issues and their resolutions with the MNO.
The first meeting with the MNO was held on January 29, 2009 between OPG representatives (including SENES Consultants Limited) and the MNO’s Director of Natural Resources, Environment and Community Relations and Captain of the regional hunt based in Timmins. The meeting was held at OPG’s office in Toronto. At this meeting, OPG provided an overview of the project, environmental assessment process and key findings. The MNO described Métis rights and the format and structure of the MNO.
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The MNO representatives indicated that there were local Métis members that fished at Mattagami Lake Dam and hunted in the general area. They also indicated that the MNO lay leadership was not yet engaged on the project and that they would need to be involved and informed.
OPG indicated at the meeting that there were only two impacts with respect to hunting and fishing. First, there would be restriction of public access around the proposed generating station. Second Kenogamissi Falls Road would have to be closed for about one week to allow the penstock to be constructed underneath it.
The MNO representatives did not indicate that any of their rights would be impacted but that they wished to be consulted further on the project and would need to raise the issue with their Regional Consultation Committee.
A second meeting was held on March 27, 2009 among the MNO, OPG and Mattagami First Nation. Two representatives from MOE also attended this event as an observer. This meeting was held at OPG in Toronto and coincided with an MNO provincial event. The MNO had in attendance their Regional Councillor and Presidents of their Northern Lights, Temiskaming and Timmins Councils, Captain of the Hunt, Director of Natural Resources, Environment and Community Relations and Manager of Community Relations.
At this meeting, OPG provided an overview of the Project, the environmental assessment process and environmental assessment findings. OPG then fielded specific questions about the project and its impact from the MNO. Most of the questions were general in nature with some specific questions around hunting and fishing. OPG indicated that hunting and moose populations would not be impacted by the Project but that there would be restriction of public access around the proposed generating station and that Kenogamissi Falls Road would have to be closed for about one week to allow the penstock to be constructed underneath it.
Chief Naveau of the Mattagami First Nation then spoke about his community and that the project is occurring on their traditional territory. He indicated that MFN is working with OPG on this project and that the project was commenced based on a request from his community. He indicated he thinks the project is being done in an appropriate manner to protect the environment and that his community would like to move this project forward. He also asked specifically what the concerns of the MNO were.
The MNO indicated that they were at the meeting to learn about the project and about how it might impact the land. They wanted to know how the environment would be protected. They indicated that they did not want to take anything away from MFN and were not seeking financial compensation.
The MNO indicated that they needed some time to think about the meeting today and would then get back to OPG and MFN about any outstanding concerns.
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A third meeting was held on May 20, 2009 in Timmins among OPG, the MNO and Mattagami First Nation to see if there were any outstanding issues for the Métis associated with the project.
Chief Naveau started the meeting by stating three concerns. First, as these lands are MFN’s traditional lands, the Métis should have come to Mattagami First Nation with their concerns and not OPG. Second, he asked that Métis not try to take anything away from the Mattagami First Nation. Third, that the he is happy to sit with the Métis and talk about the Way of Life, but first closure is needed on the project. The MNO indicated that they were not interested in taking anything away from the First Nation, nor do they want to delay the project. They indicated that they wanted to ensure that their views and concerns are heard, and dealt with. The MNO agreed that OPG has presented information on the project both the engineering aspects and have identified and discussed the environmental impacts. The MNO identified three issues which they would like to resolve.
First, the MNO were concerned about the temporary road closure on Kenogamissi Falls and that they might potentially have harvesters trapped behind the closure. OPG re-iterated that they would co-operate with the MNO in notifying Métis members about the closing at the appropriate time.
Second, the MNO indicated that they were opposed to the use of herbicides for vegetation suppression on transmission lines. OPG indicated that they are committed to keeping the vegetation down along the transmission corridor through mechanical rather than chemical means.
Third, the MNO indicated that they would like to visit the site during construction and be made aware of what efforts are made during construction to protect the environment. MFN and OPG agreed that the MNO would be invited to the site a couple times during construction to view activities. OPG indicated that this request should be made through MFN.
As the above three issues were all resolved the MNO indicated they had no outstanding concerns with the project.
6.2.5 Summary
As documented in this report, consultation with Mattagami First Nation on the Proposed Undertaking has been extensive. This is primarily because Mattagami First Nation is a potential partner on the project with OPG; and the location of the Proposed Undertaking is in close proximity to the Mattagami First Nation Reserve and clearly within their traditional territory.
For all the above reasons, consultation has been extensive with Mattagami First Nation. A total of four community meetings have been held along with several meetings with the Mattagami First Nation Chief and Council. In addition, two Mattagami First Nation Councillors participated with the team through out the environmental assessment process. As well, a member of
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Mattagami First Nation and their former Resource Liaison Officer has been a part of the SENES Consultants Limited environmental assessment team. Given the above, OPG believes that Mattagami First Nation has been fully consulted on with respect to the Proposed Undertaking.
While three other First Nations were contacted about the project, to date they have not indicated an interest in being consulted on it. It is likely that they have recognized that this: is a project done in partnership with Mattagami First Nation; and, that the project’s location is clearly within Mattagami First Nation’s traditional territory.
Extensive consultations were held with the Métis Nation of Ontario and the concerns and questions of the MNO were fully resolved.
Based on the assessment of the project’s impact and the potential impact on First Nations rights, values and interests it was determined that the consultation described in this report is sufficient and consistent with Supreme Court of Canada Decisions on consultation requirements with Aboriginal peoples. It is the opinion of OPG and SENES that the consultation was open, inclusive and meaningful.
It is the view of OPG that the First Nations consultation program was thorough, appropriate, well documented and consistent with the First Nations and Aboriginal Peoples rights, values and interests and the proposed project’s impacts. MNR has been involved at key stages of the process and was consulted on the overall First Nations consultation plan, attended First Nations meetings and was apprised of progress throughout the Project.
It is OPG’s opinion that the environmental assessment process is the most logical spot in which to undertake consultation with First Nations and Aboriginal peoples; and determine the significance of impact on Aboriginal and Treaty rights. By its very nature, the environmental assessment process in Ontario is intended to be a holistic process taking into account the full diversity of impacts associated with an undertaking on the natural, social and economic environments. In contrast, government permits, approvals and clearances associated with latter stages of the approvals process are highly detailed and specifically focused on smaller aspects of the overall project.
While OPG understands that the Crown may take the opinion that formal legal discharge of the duty to consult is when an actual permit is applied for and granted, it is OPG’s opinion that the consultation, assessment of impact and application of mitigation is far more effectively done during the EA process when the totality of impacts can be explained to First Nations and Aboriginal Peoples and assessed by both the impact assessment team and by the First Nations and Aboriginal peoples specifically affected.
It is the view of OPG that the environmental assessment is the appropriate decision-point for the Crown to consult with First Nations as it is the only decision point that integrates overall project impacts with an assessment of potentially affected First Nations and Aboriginal Peoples rights, values, interests and resources.
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7.0 SUMMARY EVALUATION OF THE PROPOSED UNDERTAKING
7.1 ADVANTAGES AND DISADVANTAGES OF THE PROPOSED UNDERTAKING
As per Section B.3.3 of the Guide an overall assessment of the advantages and disadvantages of the Proposed Undertaking is provided below including a discussion of any benefits that may offset negative environmental effects.
7.1.1 Advantages
The Proposed Undertaking produces a wide variety of benefits for the people of Ontario, OPG, Mattagami First Nation and the local communities.
The Proposed Undertaking benefits Ontario as it adds approximately 5 - 7 megawatts of clean, renewable hydroelectric power to Ontario’s supply. It can do this while capitalizing on an existing asset (the existing Mattagami Lake Dam) on an already managed river.
The Proposed Undertaking adds a small amount of renewable power to OPG’s existing hydroelectric assets. This occurs in an area already managed by OPG hydroelectric staff and therefore no unique operational challenges. OPG is also eager to work co-operatively with First Nations in Ontario.
The Proposed Undertaking represents an economic development and employment opportunity for Mattagami First Nation. This most likely represents the closest and largest hydroelectric opportunity for MFN.
The Proposed Undertaking will result in a small but important local economic benefit to the communities of Gogama and Timmins during the construction stage. As well, it assists in securing the existing permanent employment associated with OPG’s NEPG operations.
The Proposed Undertaking will be operated in compliance with the amended MRSWMP. An ecological flow requirement has been agreed to by OPG and government agencies and the agreement would be included in the MRSWMP via a minor amendment.
The proposed GS will be operated remotely and maintained by OPG’s Northeast Plant Group staff located in Timmins. An automated gate will facilitate faster response to changing conditions in the Mattagami Lake watershed than the current on-site operations that are required as the flows and levels in the system change.
7.1.2 Disadvantages
As identified in this ERR, OPG and SENES are of the opinion that there are no net aquatic ecological disadvantages associated with the project, assuming all the mitigation and monitoring
Final 7-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station measures identified in this Report are carried out. The Proposed Undertaking can be done without making any changes to the water levels identified in the Water Management Plan for the Mattagami River System.
With respect to the terrestrial environment, the Proposed Undertaking will result in the clearing of a small amount of land for the proposed GS and transmission line. The total land to be cleared is approximately 13 hectares and is not considered ecologically significant, and no unique features or values are associated with this land. Some of this land has also been degraded through the construction of a previous utility line and forest clearing.
The only disadvantage with the Proposed Undertaking that cannot be mitigated is that the area around the proposed GS will be removed from public use. OPG is of the opinion that this area must be removed from public use following construction as an important public safety measure. The removal of this area from public use impacts the occasional recreational angler. Given that Timmins District has no shortage of fishing spots and the population in the general area is very sparse it is of OPG’s opinion that the impact is very minor.
7.2 SUMMARY OF MITIGATION AND MONITORING COMMITMENTS
7.2.1 Proposed Mitigation Measures
This is a summary of the proposed mitigation measures identified in the ERR.
Blasting
Explosives used in construction will be closely controlled, with their use restricted to authorized personnel who have been trained in the use of explosives in a manner so as to minimize impacts on the environment. Appropriate government agencies will be informed of the blasting schedule in advance of construction, as well as just prior to the detonation program. All necessary permits will be obtained by the Contractor hired by OPG, who will also comply with all legal requirements in connection with the use, storage and transportation of explosives, including, but not limited to, the Canada Explosives Act and the Transportation of Dangerous Goods Act. The Contractor will be required to retain a consulting engineer with technical expertise in blasting to provide advice on maximum loading of explosives for all blasting, as well as an engineering report indicating recommended charges and blasting methods to be used at specific locations. All blasting will occur in such a way as to be in compliance with federal regulations and directions. Blasting should adhere to the Fisheries and Oceans Guidelines for the Use of Explosives in or Near Canadian Fisheries Waters (http://www.dfo-mpo.gc.ca/canwaters-eauxcan/infocentre/guidelines- conseils/guides/explosguide/chap3_e.asp#GUIDELINES).
The potential use of fragmented rock generated by blasting activities for fish habitat enhancement and/or use for nearshore/shoreline erosion protection will be discussed with DFO.
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Otherwise, the excess rock will be removed from the dewatered areas behind the temporary cofferdams for suitable upland disposal.
Erosion and Sedimentation Control
Erosion and sediment control will be an integral component of the construction planning process. All personnel involved with the proposed works will be briefed on erosion and sediment control including engineers, contractors, inspectors and environmental staff. In general, the following guidelines will be applied in the development of the Erosion and Sediment Control Plan:
• Fitting of proposed works to the terrain; • Timing of grading and construction activities to minimize soil exposure; • Retention of existing vegetation where feasible; • Restriction of the use of heavy construction equipment to within the approved work areas to minimize soil disturbance and vegetation destruction; • Storage of stripped soil at upland locations; • Implementation of erosion control measures, e.g. rip rap berms underlain by filter geotextile, straw bales used as filters, silt fencing along the shoreline and/or mulching for interim stabilization; • Diversion of runoff away from exposed areas; • Minimization of the length and steepness of slopes; • Maintenance of low runoff velocities; • Design of drainage works, such as ditches and outfalls, to handle concentrated runoff; • Retention of sediment on site; • Routine inspection and maintenance of erosion and sediment control measures; and, • Re-vegetation of disturbed areas by seeding and/or planting following construction as soon as seasonal conditions permit.
Rehabilitation of the Site
After construction of the proposed GS, the development site will be rehabilitated. A Site Rehabilitation Plan including planning considerations, soil stabilization and re-vegetation will be prepared.
Control of Dust
Dust may be generated during the construction of the proposed GS due to heavy equipment movement. Dust generation during dry, windy conditions can be controlled by water trucks and/or sprinklers as necessary to reduce dust to acceptable levels (Cheminfo 2005).
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Spills and Waste
Fuelling and lubrication of construction equipment should be carried out in a manner that minimizes the possibility of releases to the environment. Measures for containment and cleanup of contaminant releases should be followed to minimize contamination of the natural environment, e.g., placement of fuel tanks and generators on plastic sheets bermed around the edges, and use of suitable hydrocarbon absorbent material for cleanup and approved landfill or other disposal. Any spills with the potential to create an impact to the environment should be reported to the MOE as required by provincial spills legislation. Interim sanitary waste collection and availability of treatment facilities should be arranged for the duration of the construction period. All construction waste, wash water and wastewater should be disposed of in accordance with regulatory requirements.
A Hazardous Materials Management Plan, Waste Management Plan and a Spills Emergency Preparedness and Response Plan will be developed as part of a broader Environmental Management Plan that is to be developed and implemented by the contractor.
Forest Resources
The proposed transmission line impacts a total of 10.2 hectares of forest and 0.4 hectares of non-forested land. It appears as if silvicultural investments occurred on 4.41 hectares of this land and the loss can be compensated by OPG if necessary by paying approximately $5,000 to the Forest Renewal Trust Fund.
A small Forest Resource License (FRL) would be required from MNR to harvest the timber from the selected route. Wood would have to be skidded out to the existing roads to allow it to be utilized. Stumpage fees would be due to the Crown on the 74 cubic metres of merchantable volume. The volume is too small to be easily marketable, given its locations far from the mills. Therefore, one other option may be to provide the entire volume to MFN as fuelwood if that was considered acceptable to MNR.
Incidentally, it is of note that White Pine is normally left standing after harvest by Tembec. Occasionally, there may be one contractor who harvests White Pine. There were a few large White Pine trees observed within or adjacent to the preferred alternative corridor and these may have to be cut to allow for the transmission line. If the trees are on the edge of the transmission line corridor they may be avoided by re-aligning the corridor. This would be addressed as part of the forest resource license.
Vegetation Clearing
Vegetation clearing will adhere to standard construction practices as listed below:
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• Vegetation clearing should be restricted to the minimum necessary for construction activities; • Brush and trees should be felled into the area to be cleared to prevent damage to adjacent vegetation; • Branches overhanging the cleared area should be cut (pruned) cleanly and stubs should not be dressed; • Merchantable timber should be cut and neatly stacked for removal as requested by MNR; • Specimen trees marginal to the cleared area should be identified prior to construction, flagged and protected from damage, where possible; • All slash, brush, roots and stumps are typically raked into piles for burning or disposed in a manner prescribed by MNR; and, • Slash material should not be stored near the Mattagami River.
A number of terrestrial bird species are likely locally resident and may nest on the Mattagami Lake Dam property. Most of these species are protected under the Migratory Birds Convention Act (MBCA). The Canadian Wildlife Service (CWS) has stipulated that vegetation clearing should not be undertaken during the breeding season of migratory birds in order to avoid the destruction of any bird nests. Specifically, clearing should not take place between May 1st and July 31st in northern Ontario. Otherwise, a breeding bird survey must be conducted by a qualified avian biologist and any nests found must not be disturbed by the clearing activity until the young have fledged. A buffer zone with a 50 metres allowance restricting active construction activities is usually applied around a nest. The CWS will be consulted for the appropriate mitigation measures. To preclude the potential institution of a buffer zone that may affect construction activities, it is recommended that vegetation (including grubbing) be removed prior to nesting season initiation (May 1st), or after nesting season completion (July 31st).
Use of Herbicides
Both Mattagami First Nation and the Métis Nation of Ontario indicated that they have concerns with the use of herbicides to suppress vegetation along transmission corridors during operations. As such, OPG has agreed that there would be no chemical suppression of vegetation and that mechanical means would be employed instead.
Environmental Management Plans
Environmental protection during the proposed GS construction and operation will be ensured by adherence to a site-specific Environmental Management Plan, as well as compliance with regulatory standards and guidelines.
The Environmental Management Plan for the Proposed Undertaking will ensure that environmental protection will be achieved by describing government agency requirements, OPG policy, project commitments and recommended mitigation measures to be undertaken. The
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Environmental Management Plan will include the Erosion and Sediment Control Plan, Spills Emergency Preparedness and Response Plan, Hazardous Materials Management Plan, Waste Management Plan and Site Rehabilitation Plan.
Timing of In-Water Work
In-water construction activities should be timed to avoid the spawning and incubation period of spring spawning fishes such as walleye, which typically excludes in-water work from April 1 to June 20.
In-water construction activities should be timed to avoid the spawning and incubation period of lake whitefish. The DFO guidelines suggest September 15 to May 15 for all of northeastern Ontario (Fisheries and Oceans Canada, 2010), but based upon the lake whitefish spawning investigations at the Mattagami Lake Dam, it is believed that spawning within the Mattagami River at this location does not commence until well after October 1, usually during the second half of October.
Protection of Fisheries
Whenever clearing, excavation, or construction work occurs within or adjacent to a waterbody or a watercourse that is considered fish habitat or may drain to fish habitat, the following general mitigating actions should be undertaken where appropriate.
• Dredged material should be disposed of on land above the high water level and suitably contained/stabilized to prevent the dredged material from re-entering the water. • Sediment and erosion control measures should be implemented as required prior to work and maintained during the work phase, to prevent entry of sediment into the water. This should include sediment removal from water pumped from within the work areas such as the powerhouse foundation area, draft pit and tailrace excavation. It should also include the use of silt curtains or cofferdams, if appropriate, during any in-water work to prevent deleterious substances from entering fish habitat. • All materials and equipment used for the purpose of site preparation and project completion should be operated and stored in a manner that prevents any deleterious substance (e.g. petroleum products, debris etc.) from entering the water.
Removal of Old Rock-Filled Crib Structure
With the proposed utilization of the two western-most sluice gates to divert river flow for the proposed GS, the remains of an old rock-filled crib structure located immediately upstream of the dam at this location (Figure 3-9; Aquatic TSD, Appendix A: Photograph 3) must be removed to allow the uninhibited flow of water into the GS. This old crib structure will be dismantled and its material removed to an off-site approved disposal area. To maintain the habitat function that was provided by the rock and timber crib, new, similarly sized clean rock material, will be placed
Final 7-6 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station in a similar configuration in the vicinity of the floating boom (Aquatic TSD, Appendix A: Photograph 2). To improve the utilization of this habitat by fish, the new habitat should be located in deeper water so that it remains submerged during the late winter drawdown of Mattagami Lake.
These old rock-filled wooden cribs are not large, and are primarily composed of large rocks and old logs, and therefore are not expected to generate much suspended sediments when they are dismantled. Since the surrounding lake substrates are primarily fine, any deposition from the small amount of fine material that may be attached to this wood and rock structure will not significantly impact surrounding habitats. Its removal can be accomplished without the use of a cofferdam, as the installation and subsequent removal of a cofferdam would likely constitute a greater impact than the actual work. However, a silt curtain may be warranted. If this work is undertaken within the in-water construction window for this site (June 20 to September 15), no negative impacts to fish and fish habitat are anticipated.
Powerhouse Construction and Cofferdams
While the construction methods presented here outline the basic principles that will be used to minimize the environmental impact of this work, the final design of the tailrace channel and cofferdam is the contractor’s responsibility. The construction methods presented here reflect the components of the DFO Risk Management Framework (Fisheries and Oceans Canada, 2006) and have been discussed with DFO. Generally, the powerhouse and part of the tailrace channel will be constructed in dry conditions inside a cofferdam located along the west shoreline.
As noted above these are preliminary plans and will be subject to final stamped drawings from the contractor. The powerhouse cofferdam will be constructed along the west shore of the river, downstream from the road bridge. The construction will occur in the dry over a period of 3 to 4 weeks during the low flow period, when the dam can be shut down (if necessary) with only leakage flow to the downstream river. No in-water work will occur in the tailrace area during the spawning or incubation periods of walleye, and lake whitefish (i.e. the work should normally be done between June 20 and September 15). The cofferdam toe on the river side will correspond roughly to just below the waterline associated with the average annual flow of 30 cubic metres per second, and at that water level would reduce the wetted habitat area by approximately 150 square metres. The cofferdam will stay in place for about 2 years, and be designed according to the latest Ontario Dam Safety Guidelines. The habitat area that will temporarily be unavailable to fish during this period is not spawning habitat for lake whitefish or walleye.
During the excavation and initial construction of the powerhouse and part of the tailrace channel, the excavation pit will need to be maintained in a dry condition. Surface water and leakages will be collected and pumped from the pit to a settling pond or a filter bag, or a combination of both, to remove as much suspended material as possible from the discharge water before it re-enters the river. Contouring and shaping of the tailrace channel will be
Final 7-7 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station conducted in the dry behind the cofferdam to the extent possible. Once the powerhouse is advanced to the point that its outer shell within the pit is finished and watertight, and the draft tube gates can be sealed, the cofferdam can be removed.
The cofferdam will be removed and the tailrace completed during the traditional low flow period, and during the accepted in water work window (i.e. June 20 to September 15), as indicated earlier. The existing Mattagami Lake Control Dam will be closed, allowing only leakage during the 2 to 3 week duration of this work. This should result in water levels that are low enough for the cofferdam to be removed in the dry. As the cofferdam is removed, the contouring and shaping of the tailrace can be extended outward as much as possible in the dry.
The tailrace extension into the river will require the re-contouring of approximately 500 square metres of riverbed, to allow for the efficient flow of water exiting the tailrace. At the point in time when work in the wetted portion of the river cannot be avoided, a silt curtain system will be installed to enclose the tailrace footprint area. For such a small amount of excavation within relatively clean granular substrates, a silt curtain system, rather than a second cofferdam, would be the best choice to minimize impacts to the surrounding habitats. Utilizing a new cofferdam, rather than a silt curtain, would extend the area of direct impact to include the base of the cofferdam, possibly resulting in a doubling of the area of riverbed disturbed, and increasing the duration of that disturbance. Within the area contained by the silt curtain, the tailrace can be deepened and extended to blend with the contours of the surrounding riverbed. Backhoe bucket movement speed can be adjusted to minimize the suspension of material when warranted. The native riverbed material will be used to re-contour the in-water area with the coarser materials (cobble/small boulder) placed along the edge and sloped sides of the tailrace to provide potential spawning areas for walleye, and the finer materials (sand/gravel) placed in the deeper central portions of the tailrace to provide potential spawning areas for lake whitefish. Once the tailrace construction is complete, and all potentially erodible areas are stabilized and fine suspended material is cleaned-up, the tailrace silt curtain will be removed.
Loss of Cement
There is a potential for accidental loss of cement during surface application. Any dripped cement should be recovered from the river bottom for suitable disposal prior to temporary cofferdam removal.
Rock Pool
For the “bedrock pool” located 40 metres upstream of the bridge, an ecological flow of 0.2 cms must be provided to maintain water quality as well as a maximum water depth of 11 centimetres (cm) at the outlet of the pool. To simplify compliance measurement and reporting, the minimum water level in the bedrock pool that corresponds with these conditions will be maintained and measured by OPG. If winter conditions (e.g. ice cover in bedrock pool) result in the inability of the water level gauge to accurately provide water levels, OPG staff will periodically assess the
Final 7-8 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station outlet depth by other means to ensure that the maximum depth of 11 cm is maintained. As part of the final design of the redeveloped structure, there will be an arrangement for providing the minimum flow, other than leakage from the dam.
OPG has also committed to undertaking an effectiveness monitoring program of the post- construction functionality of the bedrock pool.
Ecological Flow
A minimum 2.8 cms flow (called “Ecological Flow”) as discussed with the Ministry of Natural Resources (MNR) and the Department of Fisheries and Oceans (DFO) will be released for the duration of the year outside of the walleye spawning, incubation, hatch and dispersal period, to maintain the fish habitat in the 550 metre long river section between the tailrace of the new station and Kenogamissi Lake when the unit is not operating. The agreed-upon flow requirement balances the net economic, social and environmental benefits of the Proposed Undertaking at this site.
A minor amendment to the Water Management Plan is anticipated to accommodate the minimum flow requirements described above.
Air
A variety of best practices with respect to the control of air emissions have been identified and should be implemented on the construction site (e.g., Cheminfo, 2005). The best practices should include: plans to minimize dust generation through planning, site layout and the proper use of materials, tools and equipment; use of wind fencing; compacting disturbed soil; activity scheduling; storage piles management; minimization of drop heights; barriers to prevent dispersion of materials; avoidance of blasting where feasible; work practices for loading debris; avoidance of prolonged storage of debris; and proper techniques for the use of materials that include VOCs.
To reduce particulate emissions, effective dust suppression techniques, such as on-site watering and limiting the speed of vehicles travelling on the roads, will be used. During construction the practices and procedures outlined in the document “Best Practices for the Reduction of Air Emissions from Construction and Demolition Activities (March, 2005)” prepared by ChemInfo Services Inc. in conjunction with Construction & Demolition Multi-Stakeholders Working Group for Environment Canada should generally be followed. Some of key best practices, prepared by ChemInfo Services Inc., for the reduction of air emissions during the demolition and construction phases of the undertaking are summarized below:
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Transmission Line Height
The transmission line should be built according to the Ministry of Transportation Ontario highway clearance specifications would be more than adequate to resolve this issue.
Condition of the Bridge
It would be expected that the contractor would evaluate the condition of Kenogamissi Falls Road from Highway 144 to the bridge prior to commencing construction and bring the road back to a similar condition on completion of the project.
Road Restrictions
All roads will have a half load restriction mid-April to 1st of June.
Restrictions on Workers Hunting, Fishing and Camping
It is recommended that contractors and employees of the contractor be restricted from fishing and hunting at the site during the duration of the construction period. As well, overnight trailers and stays by workers will not be permitted.
Notification of Road Closure during Construction of Penstock
During construction of the proposed GS the penstock will need to be placed below the surface of Kenogamissi Falls Road. It is estimated that this construction may require the road to be closed for one week. If possible, the penstock will be constructed in stages so the road does not need to be fully closed. If the road needs to be closed for construction, OPG will require the contractor to negotiate the time of the year for this to occur with all permitted resource users in this area (trappers, baitfish operator, BMA operators, outfitters, prospectors, Hydro One and Tembec), the MNR District Manager and the MNR Timmins District Local Citizens Committee. Once a time has been agreed to the contractor will advertise the road closing in both English and French newspapers that service both Timmins and Gogama; notify Mattagami First Nation; and, post signage on Kenogamissi Falls Road indicating the dates of the closure at least one month prior to the first day of closing.
Cultural Resources
The impact and mitigation of the proposed GS on cultural resources is being addressed in accordance with the Ministry of Culture under the Ontario Heritage Act and in co-operation with the Mattagami First Nation. The Heritage assessments have been conducted in accordance with the Ontario Heritage Act and the guidelines recommended by the Ministry of Tourism and Culture.
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Métis Nation of Ontario
The Métis Nation of Ontario was also consulted on the project and raised three concerns which have all been resolved through mitigation measures. First, the MNO were concerned about the temporary road closure on Kenogamissi Falls Road and that they might potentially have harvesters trapped behind the closure. OPG has committed to co-operating with the MNO in notifying Métis members about the closing at the appropriate time. Second, the MNO indicated that they were opposed to the use of herbicides for vegetation suppression on transmission lines. OPG indicated that they are committed to keeping the vegetation down along the transmission corridor through mechanical rather than chemical means. Third, the MNO indicated that they would like to visit the site during construction and be made aware of what efforts are made during construction to protect the environment. MFN and OPG agreed that the MNO would be invited to the site a couple times during construction to view activities. OPG indicated that this request should be made through MFN.
7.2.2 Proposed Monitoring Measures
A proposed monitoring plan is provided in Appendix E of the Aquatic TSD. It will further document walleye and lake whitefish spawning under existing conditions and following development, as well as the effect of minimum flows upon fish habitat within the bedrock pool upstream of the GS tailrace, and within the 550 metres of river between the tailrace and Kenogamissi Lake.
7.3 POST ENVIRONMENTAL ASSESSMENT APPROVALS
Approval under the provincial EA Act is the first Provincial government approval in a series of permits, licences and approvals required for the Proposed Undertaking. Other legislation such as the Ontario Environmental Protection Act, the Ontario Water Resources Act, the Lakes and Rivers Improvement Act, the Federal Fisheries Act, and the Federal Navigable Waters Protection Act grant authority to designated provincial and federal agencies to review and approve components of the proposed works at later stages of design definition, and therefore at a greater level of detail than is typically available at the EA stage. The EA Act specifically prohibits the granting of other approvals prior to EA Act approval. A list of the environmental permits, licences, clearings and approvals for the hydroelectric generating stations is provided in Table 7.1 below. While the permits and approvals required for the Proposed Undertaking is dependent on the final designs by the contractor, a non-exhaustive list of permits and approvals is provided. Depending on the final design, many of these approvals may or may not be required; however, the list is provided for illustrative purposes and serves as a generic list.
Other EA Act approvals and communications will be initiated with all relevant government agencies to ensure an up-to-date and complete list of information. This list will be incorporated into a Project Environmental Requirements document, which will be prepared as an approvals guide for project engineering and construction staff.
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Table 7.1 List of Permits, Licenses and Approvals Possibly Required for Hydroelectric Redevelopment Pertinent Permits Agency Statute Applicability Licences or Approvals Department of The Fisheries Act Letter of Advice DFO has indicated that it Fisheries and (or Authorization required will make its final Oceans if HADD of fish habitat determination as to whether under Section 35 of the a Letter of Advice or Act). Authorization issued dependent on the final Letter of Advice if no fish design drawings to be destruction conclusion submitted by OPG and its (or authorization for the contractor. However, DFO destruction of fish by has indicated that based on means other than fishing the plans presented to them under Section 32 of the and the associated Act). mitigation and monitoring measures, this would appear to be a Letter of Advice. Department of Navigable Waters Navigable Waters Transport Canada has Transport Protection Act Protection Act Clearance advised OPG that TC will can be required. not likely have a CEAA trigger for this project. An approval under section 10(2) of the Navigable Waters Protection Act would be required to convert the existing water control structure, however this is not included under the Law List Regulations pursuant to CEAA, and therefore TC has no requirement to conduct an EA prior to issuing such an approval. Plans showing the proposed alterations would need to be submitted to the NWPA Office to initiate the approval process.
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Table 7.1 List of Permits, Licenses and Approvals Possibly Required for Hydroelectric Redevelopment (Cont’d) Pertinent Permits Agency Statute Applicability Licences or Approvals Because an existing structure is already in place and approved by Transport Canada under the NWPA and that the proposed undertaking is a minor undertaking and will not limit or prevent boating, no approval is required from Transport Canada. OPG will have regard for Transport Canada’s considerations for Portage Crossing a Road, in design of the final facility.
The transmission line meets TC’s definition of a “Minor Work” for aerial cables.
Six copies of final plans will need to be sent to Transport Canada in the permitting phase of the project. This would occur once OPG has fully accepted the final plans for the project (and they are also fully approved by MNR under the LRIA).
OPG should review with Transport Canada the proposed locations of the portage; booms, buoys, signage and other structures as indicated by TC.
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Table 7.1 List of Permits, Licenses and Approvals Possibly Required for Hydroelectric Redevelopment (Cont’d) Pertinent Permits Agency Statute Applicability Licences or Approvals NR Can Law List 7(1) (a) occurs when This is only relevant if the Regulations, the Minister issues "(a) contractor decides to paragraph 7(1)(a) licences for factories storage a certain quantity of of the Explosives and magazines". explosives on-site. This is Act is listed magazine" means unknown at this point but any building, not probable given the size storehouse, structure of the Project. or place in which any explosive is kept or stored, but does not include (emphasis added) (a) A place where an explosive is kept or stored exclusively for use at or in a mine or quarry …., (b) a vehicle in which an authorized explosive is being conveyed in accordance with this Act, (c) the structure or place in which is kept for private use, and not for sale, an authorized explosive to an amount not exceeding that authorized by regulation, (d) any store or warehouse in
Final 7-14 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Table 7.1 List of Permits, Licenses and Approvals Possibly Required for Hydroelectric Redevelopment (Cont’d) Pertinent Permits Agency Statute Applicability Licences or Approvals which are stored for sale … (e) any place at which the blending or assembling of the in explosive component parts of an authorized explosive is allowed under section 8. Department of Transportation of Explosives Required if transporting up Transport Dangerous Transportation Permit to 2000 kg of explosives. Goods Act This would be contractor’s responsibility to assess need and then obtain if required. However, it is likely not required. Ministry of the Environmental C of A (air/noise) According to MOE C of A’s Environment Protection Act are needed for only large Approval for the portable generation emissions or discharge equipment. of any contaminants into any part of the natural This would be contractor’s environment other than responsibility. water (Part II, Section 8 and Regulations). Ministry of the Certificate of Waste generator Registration for hazardous Environment Approval - Waste registration. waste generated during construction and which will be removed from the site.
This would be contractor’s responsibility but it is unlikely that it is required as there is no hazardous waste to be removed from the property.
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Table 7.1 List of Permits, Licenses and Approvals Possibly Required for Hydroelectric Redevelopment (Cont’d) Pertinent Permits Agency Statute Applicability Licences or Approvals Ministry of the Ontario Water Section 34 of the OWRA A cofferdam is most likely Environment Resources Act requires anyone taking required for the intake and it more than a total of may be of sufficient size 50,000 L of water in a that the de-watering could day from a lake, stream, be in excess of 50,000L per river or groundwater day. source, with some exceptions, to obtain a This would be contractor’s permit to take water. responsibility.
Permits to Take Water for construction and dewatering depending on volume anticipated As well, a Permit to Take Water will be required for the operation of the proposed GS.
MOE regional office (Timmins). Ministry of the Ontario Water C of A (Industrial Separate approvals would Environment Resources Act Sewage) be required for temporary settling ponds and cofferdams requiring pump outs (if required).
This is not anticipated but would be dependent on the cofferdam design submitted by the contractor. Ontario Ministry Lakes and Rivers Consolidated Work Consolidated Work Permit of Natural Improvement Act Permit under the Act must be Resources acquired from the MNR to undertake work on shore lands or works within a water body; Lakes and Rivers Improvement Act - O. Reg. 454/96.
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Table 7.1 List of Permits, Licenses and Approvals Possibly Required for Hydroelectric Redevelopment (Cont’d) Pertinent Permits Agency Statute Applicability Licences or Approvals OPG should re-iterate with MNR that their consultation with First Nations must consider all issues at once and as early as possible in the process. Ontario Ministry Lakes and River Water Management Plan The Standing Advisory of Natural Improvements Amendment Committee (SAC) will make Resources Act a recommendation to the Minor Amendment local MNR District Manager as to the categorization. OPG is of the opinion that a Minor Amendment will be required to the Mattagami River System Water Management Plan. The consultation associated with this is Notification. Ontario Ministry Lakes and Rivers Location Approval Part of the Lakes and of Natural Improvement Act Rivers Improvement Act Resources approvals. Ontario Ministry Lakes and Rivers Plans and Specification Part of the Lakes and of Natural Improvement Act Approval Rivers Improvement Act Resources approvals. Ontario Ministry Public Lands Act Amendment to Water OPG is currently holding of Natural Power Lease discussions with MNR on Resources Agreements changes to the existing Lease in order to secure the necessary tenure. Ontario Ministry Public Lands Act Amendment to Licence OPG has a LO for the of Natural of Occupation (LO) if existing dam. This LO will Resources head pond area changed need to be replaced by a Water Power Lease to operate and maintain the new GS and associated land areas.
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Table 7.1 List of Permits, Licenses and Approvals Possibly Required for Hydroelectric Redevelopment (Cont’d) Pertinent Permits Agency Statute Applicability Licences or Approvals Ontario Ministry Public Lands Act Work Permit A Work Permit to do work of Natural on shorelands or within a Resources water body might be required under the PLA O. Reg. 453/96. Ontario Ministry Fish and Wildlife Licence to Collect Fish This permit is required from of Natural Act for Scientific Purposes MNR in order to capture Resources and transfer fish following the construction of the cofferdams and the de- watering of the area behind them. Ontario Ministry Crown Forest Forest Resource Licence FRL will be required along of Natural Sustainability Act – Clearance to Harvest with overlapping agreement Resources with Tembec, which is the Clearance required to cut Sustainable Forest Licence timber on Crown land (all holder. OPG sites are on Crown land). To obtain licence and agreement with Tembec and assessment of the loss of merchantable timber is required. This is being done as part of the environmental assessment. Ministry of Ontario Heritage Further Ministry of Culture Act Culture approval may be required. Ministry of Dangerous Waste Manifest If materials are Transportation Goods contaminated, will need to Transportation ensure manifests etc are in Act place if waste is to be transported off site.
This is contractor’s Responsibility. Ministry of Planning Act Official Plan and Zoning The subject site occurs in Municipal By-Law Designation an unincorporated Affairs and township. This is under the
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Table 7.1 List of Permits, Licenses and Approvals Possibly Required for Hydroelectric Redevelopment (Cont’d) Pertinent Permits Agency Statute Applicability Licences or Approvals Housing jurisdiction of MAAH.
No Ministers Zoning Orders in this part of the Province.
No approvals required. Ministry of Ontario Build No permit from the No building permit required Municipal Code Act Province, but the building as the subject site occurs in Affairs and must be compliant with an unincorporated Housing the Ontario Building township. Code. Sudbury and Ontario Building Sewage System Permit Permit will be required for District Health Code Act septic system installation. Unit An “Information Package Involving Applications for a Sewage System Permit” and “Application for a Permit to Construction or Demolish” (authorized under Building Code Sentence 2.4.1.1A. (2) is available from the Sudbury and District Health Unit.
7.4 CONCLUSION
This Environmental Review Report (ERR) provides: a rationale for the Proposed Undertaking, its location and technical alternatives; a description of the local environment; a summary of public and government concerns and suggestions; description of environmental effects; and recommended mitigation and monitoring options. Opportunities have been given for input from government reviewers in the scoping of field studies, the identification of effects, selection of potential mitigation measures, and the content of the ER document and review of Technical Support Documents. Through meetings, discussions and information centres/open houses and web site, substantial efforts have been made to inform and involve the public in the project, and to develop a clear understanding of their concerns. Ontario Power Generation continues to participate in the Mattagami River Standing Advisory Committee, to address issues associated with Mattagami River Water Management and hydroelectric operations.
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As described previously, the Proposed Undertaking will provide a benefit to the people of Ontario by adding more clean renewable power to the Province. It will benefit Mattagami First Nation by creating a potential economic and employment opportunity for the community. It will provide economic benefits to the local area and the region during the construction period and improve the security of the existing operational employment in the area. Lastly, this will occur on a river that is already managed, where infrastructure is in place and where there are fewer uncertainties than on an unmanaged river system. It is believed that the Proposed Undertaking will not adversely impact the terrestrial or aquatic environments, through the application of a wide variety of mitigation and monitoring measures.
A key objective of this assessment was to identify and resolve all project issues, in advance of the 30 day review period stipulated within the Guide. It is OPG’s understanding that this objective has been achieved. If outstanding concerns remain after submission of this ERR, a bump-up procedure is available for consideration of those concerns. The final result may be resolution of the issues, agreement to deal with the issues through another process, possible amendments to the document, or, if necessary, formal submission of the EA for review and approval as an individual EA under the terms and conditions of the EA Act.
Ontario Power Generation respectfully requests acceptance of the Proposed Undertaking as described herein, under the terms of the Guide. This document also provides information on the projects in order for the Department of Transport (Canadian Coast Guard), Department of Fisheries and Oceans Canada and other relevant federal authorities to provide the necessary clearances.
Final 7-20 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
8.0 REFERENCES
Associate Committee on the National Building Code (ACNBC) 1980. The Supplement to the National Building Code of Canada. National Research Council of Canada. NRCC No. 17724: 293 p. Barnett, P.J. 1992. Quaternary Geology of Ontario. In: Geology of Ontario. Ontario Ministry of Northern Development and Mines. Ontario Geological Survey Special Publication 4: 1011-1090. BC Ministry of Energy and Mines 1997. Draft Guidelines and Recommended Methods for the Prediction of Metal Leaching and Acid Rock Drainage at Mine Sites in British Columbia. Becker, G.C. 1983. Fishes of Wisconsin. Univ. of Wisconsin Press. Madison, Wisconsin. 1052 p. BPR Energie. 2007. Geotechnical Investigation Report. Mattagami Lake Dam Generation Development, Timmins, Ontario. Prepared for Ontario Power Generation. Report File 07.08.216 G (Draft, October 2007). Brousseau, C.S. and G.A. Goodchild 1989. Fisheries Yields in the Moose River Basin, Ontario, pp. 145-158. In: D.P. Dodge [Ed.]. Proc. Internat. Large River Symposium. Can. Spec. Publ. Fish. Aquat. Sci. 106. Cadman, M.D., P.F.J. Eagles and F.M. Helleiner 1987. Atlas of Breeding Birds of Ontario. University of Waterloo Press, Waterloo, Ontario. 617 p. Canadian Wildlife Service (CWS) 1990. A Wildlife Policy of Canada. Wildlife Ministers’ Council of Canada. 29 p. Chapman, L.J. and M.K. Thomas 1968. The Climate of Northern Ontario. Canada Department of Transport, Climatological Studies No. 6: 58 p. Cheminfo Services Inc. (Cheminfo) 2005. Best Practices for the Reduction of Air Emissions from Construction and Demolition Activities. Construction and Demolition Multi- stakeholder Working Group Report to Environment Canada, Transboundary Issues Branch. 49 p. City of Timmins. Community and Business Profile 2006. A Bold Vision – A Bright Future. Coad, B.W., H. Waszczuk, and I. Labignan 1995. Encyclopedia of Canadian fishes. Canadian Museum of Nature and Canadian Sportfishing Productions Inc. 928 p. Committee on the Status of Endangered Wildlife in Canada (COSEWIC) 2006. Canadian Species at Risk. 25 April 2006. Ottawa, Ontario. 76 p. Environment Canada (EC) 2008a. Narrative Descriptions of Terrestrial Ecozones and Ecoregions of Canada. http://www.ec.gc.ca/soer- ree/English/Framework/NarDesc/canada_e.cfm Environment Canada (EC) 2008b. National Climate Archive. http://climate.weatheroffice.ec.gc.ca/. Committee on the Status of Endangered Wildlife in Canada (COSEWIC) 2010. Canadian Species at Risk. Ottawa, Ontario. http://www.cosewic.gc.ca/eng/sct5/index_e.cfm. Environment Canada, Canadian Wildlife Service (EC CWS) 2004. Species at Risk Web Mapping Application (http://www.sis.ec.gc.ca/ec_species/ec_species_e.phtml), accessed on 22 February 2007.
Final 8-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Erskine, A.J. 1977. Birds in Boreal Canada: Communities, Densities and Adaptations. Canadian Wildlife Service Report Series No. 41: 71 p. Fisheries and Oceans Canada. 2006. Practitioners Guide to the Risk Management Framework for DFO Habitat Management Staff. Version 1.0. Habitat Management Program, Fisheries and Oceans Canada. Griffiths, W.H. and B.D. Walton 1978. The Effects of Sedimentation on the Aquatic Biota. Prepared for the Alberta Oil Sands Environmental Research Program by Renewable Resources Consulting Services Ltd. AOSERP Report 35. Hirsch, N.D., L.H. DiSalvo and R. Peddicord 1978. Effects of Dredging and Disposal on Aquatic Organisms. U.S. Army Engineer Waterways Experiment Station, Vicksburg, Miss., Tech. Rpt. DS-78-5: 41 p. Hogg, P., Davies, J.C., Parton, J., Vukelich, M., Fournier, R., and A. Bisset 1995. Predicting Moose Population Size Using Harvest Survey Information. Northeast Science & Technology (NEST) Technical Report TR-021. Report. 8 p. Luedtke, R.J. and M.A. Brusven 1976. Effects of Sand Sedimentation on Colonization of Stream Insects. J. Fish. Res. Board Can. 33: 1881-1886. McKenney, D.W., Rempel, R.S., Venier, L.A., Wang, Y., and A.R. Bisset 1998. Development and Application of a Spatially Explicit Moose Population Model. Can. J. Zool. 76: 1922-1931. Ministry of Natural Resources (MNR) 2010. Species at Risk in Ontario List. http://www.mnr.gov.on.ca/mnr/speciesatrisk/status_list.html. Natural Heritage Information Centre (NHIC) 2010. Species and Natural Areas Information. http://nhic.mnr.gov.on.ca. Ontario Ministry of Municipal Affairs and Housing (OMMAH) 2005. 2005 Provincial Policy Statement. 37 p. Ontario Power Generation Inc., Tembec Industries, Brookfield Power and Ontario Ministry of Natural Resources (OPG et al.) 2006a. Mattagami River System Water Management Plan (Final). Peck, G.K. and R.D. James 1987. Breeding Birds of Ontario Nidiology and Distribution. Rosenberg, D.M. and N.B. Snow 1977. A Design for Environmental Impact Studies with Special Reference to Sedimentation in Aquatic Systems for the Mackenzie and Porcupine River Drainages, pp. 65-78. In: Proc. Circumpolar Conf. Northern Ecology. 15-18 September 1975, Ottawa, Ontario. Rowe, J.S. 1977. Forest Regions of Canada. Canadian Forestry Service, Publication No. 1300: 172 p. http://www.globalforestwatch.org/common/canada/map.1.pdf. Scott, W. B., and E. J. Crossman 1973. Freshwater Fishes of Canada. Bull. Fish. Res. Bd. Can. 184. 966 p. Sears, S.K. 1992. Upper Mattagami River, Small Hydraulic Assessment & Retrofit Program, Lower Sturgeon GS, Sandy Falls GS & Wawaitin GS, Concept Phase Environmental Evaluation. Ontario Hydro, Hydroelectric Engineering and Construction Services Division, Report No. 92227: 86 p. Settlement Surveys Ltd. 1995. Archaeological and Historical Sites Cultural Heritage Project. Prepared for the Elk Lake Community Forest, Elk Lake, Ontario.
Final 8-2 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Seyler, J. 1997. Biology of Selected Riverine Fish Species in the Moose River Basin. OMNR, Northeast Science & Technology. Timmins, Ontario. IR-024. 100p. Tembec 2006. Romeo-Malette Forest; Contingency Forest Management Plan 2007-2009. Tembec Final Plan Submission. Report. 39 p. Woodland Heritage Services Ltd. Stage 1 & 2 Project Report. Archaeological and Cultural Heritage Impact Assessment of the Mattagami Lake Dam Project. 2007. Woodland Heritage Services Ltd. 2008. Stage 3 Archaeological/Cultural Heritage Assessment Mattagami Lake Dam Archaeological Site DaHj-1.
Final 8-3 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
ACKNOWLEDGEMENTS
The Mattagami Lake Environmental Assessment is the product of the efforts and contributions of a great many individuals and groups whose efforts are greatly acknowledged: Matt MacDonald, Mahir Aydin, Gillian MacLeod, Mario Durpeos, Chad Plant, Brian Perrault, Joe Heil, Bill McKinlay, Richard Schwass, Chirasti Mendis, Sheng Wang, (Ontario Power Generation); Chief Walter Naveau, Councilor Gerald Luke, Councillor James Naveau (Mattagami First Nation); Don Gorber, Phil Shantz, Bernard Lebeau, and Cara Sanders (SENES); Chris McKay (W.C. McKay Consulting Services); Cam Portt and George Coker (C.M. Portt and Associates), Dr. John Pollock, George Pollock and Luke Dalla Bona (Woodland Heritage); Mark Fleming (Fleming Professional Forestry); and, Francois Vitez and Bernard Munger (SCP).
Final AC-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
LIST OF ABBREVIATIONS, ACRONYMS AND UNITS OF MEASUREMENT
# Number & And
ACNBC Associate Committee on the National Building Code AES Atmospheric Environment Service ANSI Area of Natural and Scientific Interest BMP Best Management Practice CEAA Canadian Environmental Assessment Agency Cheminfo Cheminfo Services Inc. CLI Canada Land Inventory COSEWIC Committee on the Status of Endangered Wildlife in Canada COSSARO Committee on the Status of Species at Risk in Ontario CUM Cultural Meadow CWS Canadian Wildlife Service DFO Department of Fisheries and Oceans Dillon Dillon Consulting Ltd. e.g. For example EA Environmental Assessment ELC Ecological Land Classification ER Environmental Report ESA Environmentally Sensitive Area et al. And others Etc. And so on FOM Mixed Forest FN First Nation GLL Gartner Lee Limited GS Generating Station HADD Harmful alteration, disruption and destruction (of fish habitat) HEPCO Hydroelectric Power Commission of Ontario i.e. That is LRIA Lakes and Rivers Improvement Act < Less than ML/ARD Metal Leaching and Acid Rock Drainage MNR Ministry of Natural Resources MOE Ontario Ministry of the Environment N North No. Number NEPG Northeast Plant Group (Ontario Power Generation) NHIC Natural Heritage Information Centre MMAH Ministry of Municipal Affairs and Housing
Final AB-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
O,M&A Operations, Maintenance and Administration OPG Ontario Power Generation Inc. OWRA Ontario Water Resources Act pers. comm. Personal communication PWGSC Public Works and Government Services Canada Q2 Second Quarter (of the year) S1 Extremely rare in Ontario; usually fewer than 5 occurrences (in a 10-km by 10-km Mercator square grid) S2S3 Very rare to uncommon in Ontario S3 Rare to uncommon in Ontario; usually between 20 to 100 occurrences (in a 10-km by 10-km Mercator square grid) S3S4 Rare to common in Ontario S4 Common in Ontario; apparently secure, usually more than 100 occurrences (in a 10-km by 10-km Mercator square grid) S4S5 Common to very common in Ontario S5 Very common in Ontario, demonstrably secure SE Exotic; not believed to be a native component of Ontario’s fauna SENES SENES Consultants Limited SH Historically known from Ontario, but not verified recently sp. One species SU Status uncertain SZN Not of practical conservation concern as there are no clearly defined occurrences TS Transformer Station TTN Taykwa Tagamou Nation TSD Technical Support Document W West WMP Water Management Plan
Final AB-2 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Measurement Units
° degree °C degree Celsius GWh gigawatt-hour ha hectare Hz hertz Kg kilogram km kilometre Km2 Square kilometre km/h kilometre per hour kV kilovolt m metre m2 square metre mm millimetre mm/s millimetric per second m3/s cubic metre per second M million MW megawatt PY person year ’ minute /km2 per square kilometre % percent ” second
Final AB-3 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
GLOSSARY
Avifauna Birds. Boreal Of the north. Canal A channel dug or built to carry water. Capacity The greatest load which a unit, station or system can supply (usually measured in kilowatts, megawatts, etc.). Capacity Ratio of the actual energy produced to the maximum energy which could be Factor delivered under continuous operation at maximum rating. Chute A steeply-inclined natural passageway or constructed pipe or channel which conveys water from a higher to a lower level. Cofferdam A temporary dam made of concrete, rockfill, sheet-steel piling, timber/timber- crib or other non-erodible material and commonly utilized during construction to exclude water from an area in which work is being executed. Coniferous The largest terrestrial biome on earth (also known as the Taiga or boreal Forest forest) extending in a broad band across North America, Europe and Asia to the southern border of the arctic tundra and usually dominated by one or two species of evergreen trees, Dam A concrete or earthen barrier constructed across a river and designed to control water flow or create a reservoir. Deciduous In the Northern Hemisphere, this forest type occurs to the south of the Forest coniferous forest and is dominated by broadleaved deciduous hardwood trees typically with a five- to six-month growing period. Diabase A fine-grained, dark colored igneous rock composed of lath-shaped plagioclase (feldspar) crystals surrounded by smaller grains of pyroxene and olivine; it commonly occurs as tabular bodies (dikes and sills) intruded into surrounding rocks. Dike The vertical veins of igneous rock that form when magma enters and cools in fractures found within the crust. Flash board A wood plank, steel member or inflatable rubber membrane placed at the top of a spillway to increase the storage capacity of a reservoir. Forage Any food suitable for livestock. Forebay The part of a dam’s reservoir that is immediately upstream from the powerhouse. Freshet High flows in a stream or river, usually occurring in the spring, caused by snow melt, runoff, heavy rains and/or high inflows. Geotechnical Concerned with the physical properties of soil, rock and groundwater usually in relation to the design, construction and operation of engineered works. Glaciofluvial Of glacial watercourses. Grey Wooded Well to imperfectly drained soils that have developed under coniferous and mixed-forest vegetation, as have Podzolic soils, but differ from them in having an accumulation of clay in the B horizon, neutral to slightly acid A and B horizons, and an alkaline parent material.
Final G-1 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Greywacke A hard coarse-grained sandstone characterized by angular particles of quartz, feldspar and other rock fragments embedded in a matrix of clay-sized particles. Head The difference in elevation between the water surface at the intake and tailrace. Headpond The reservoir from which water is extracted for power generation or spillage. Herpetofauna Amphibians and reptiles. (Herpetiles) Igneous Rocks formed from the solidification of molten magma either beneath (intrusive igneous rock) or at (extrusive igneous rock) the earths’ surface. Intake A structure which regulates the flow of water into a water-conveying conduit. Isostatic The upward movement of the Earth’s crust following depression of the crust rebound by the weight of ice during continental glaciation. Lacustrine Of lakes. Organic Soils that have developed from accumulations of organic materials such as grasses, reeds, rushes, sedges, mosses and ferns. Perennial Continuing, enduring or growing through the year or through many years. Podzolic Well and imperfectly drained soils that have developed under coniferous and mixed-forest vegetation and usually found in cold to temperature climates on acid parent materials. Powerhouse A primary part of a hydroelectric facility where the turbines and generators are housed and where power is produced by falling water rotating turbine blades. Riparian Of or on a river bank. Sedimentary Rock formed by the deposition, alteration and/or compression and lithification of weathered rock debris, chemical precipitates, or organic sediments. Shale Fine-grained sedimentary rock composed of lithified clay particles. Sluiceway An open channel designed to divert excess water which could be within the (Sluice) structure of a hydroelectric dam or separate of the main dam (see spillway). Spillway A passageway, or channel, located near or at the top of a dam through which excess water is released or “spilled” past the dam without going through the turbine(s); as a safety valve for the dam, the spillway must be capable of discharging major floods without damaging the dam while maintaining the reservoir level below some predetermined maximum level. Stoplog A gate (sometimes made from squared lumber) which can be placed into an opening to shut off or regulate the flow of water. Tailrace A channel through which the water flows away from a hydroelectric plant following its discharge from the turbine(s). Terrestrial Belonging, living on or growing in the earth or land.
Final G-2 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
Turbine A mechanism in an electrical generation facility which converts the kinetic and potential energy of water (in the case of hydroelectric turbines) into mechanical energy which is then used to drive a generator converting mechanical to electrical energy. Weir A dam in the river to stop and raise the water.
Final G-3 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station
APPENDIX A
DISPOSITION REPORT COMMENTS
Final November 2010 MATTAGAMI LAKE DAM GENERATING STATIONS – GOVERNMENT AGENCY COMMENTS ON MLD ERR AND TSDs
Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table MINISTRY OF NATURAL RESOURCES COMMENTS
1 Full Document Numerous dates have been given for work-in-water and Whitefish Spawning. The mention of the Smallmouth bass will be removed Change made The May15 - July 15 timing restriction to protect smallmouth bass during their from the text. throughout. spawning period is not necessary because the conservation of smallmouth bass is not one of our fisheries management objectives for this site. Regarding timing windows. The official in-water work Smallmouth bass are not native to the Upper Mattagami River and their window ends on Sept 15, but in discussions with invasion of northern lakes and rivers in Ontario poses a threat to some Connie Smith (DFO) about a year or more ago, she aquatic ecosystems. A timing restriction for walleye spawning is still agreed with G. Coker that the window is a standard necessary from April 1 to June 20; thus, in-water work at Mattagami Lake applied over a very wide area, and is a guideline. If Dam can begin three weeks earlier than recommended in the Environmental local conditions allow it to be adjusted, then they will Review Report, on June 21 of any year. consider the change. Based on our work at this location, as well as the discussions in our meetings MNR Timmins District uses September 15 as a standard end date for work in with MNR, OPG/SENES thought that October 1 was water to protect whitefish during their spawning period. An extension to still well before the start of whitefish spawning, and October 1st might be granted through the permitting process on a case-by- would be agreeable to MNR and DFO. case basis, depending on local and seasonal time-specific conditions such as water temperature, but OPG and/or its contracted construction agency The Aquatic TSD has been changed to reflect the should plan to complete work in water by September 15. Work in water will official date of Sept 15, but the statement justifying not be permitted at this site after October 1st or after the onset of whitefish the Oct 1 date has been retained for information spawning temperatures (~7.8°C from Scott and Crossman 1973), whichever supporting any future request to extend the inwater comes first. Please check all documents included in the Environmental work window. Review Report reflect this. Executive Summary 2 ES-3 7 The Executive Summary states that, "There will be no changes in the volume As this is an Executive Summary and the full ERR, ES of water, and no significant changes in water velocity, passing over the assessment is described in more detail in the Report, critical walleye and lake whitefish spawning habitat during the respective OPG proposes to delete the whitefish spawning spawning and incubation periods for these species". This is only true for reference in this sentence. OPG does note that walleye. With the proposed operating regime, flows of 8-12 cms could be there is currently no minimum flow in the MRSWMP replaced by flows of 2.8 cms during the whitefish spawning period, should a for this site for whitefish. dry low-flow summer extend into October. The volume and velocity of water will therefore be lower than they would have been in the absence of the GS operations. This statement is repeated in Section 4 on page 4-26. 3 ES-4 7 There is a statement that indicates that there will be a "... Moderate Correct. The Executive Summary does use the word ERR, ES economic benefit..." but in section 4.2.4 there is a statement that the “moderate” to describe the economic impact during economic benefit will be positive and minor following construction. Please construction. Section 4.2.4 of the ERR is a wildlife
Final A-1 March 2011 MATTAGAMI LAKE DAM GENERATING STATIONS – GOVERNMENT AGENCY COMMENTS ON MLD ERR AND TSDs
Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table rationalize. section. But if the origin of the Comment is in describing the economic impact of construction versus operations we have indicated that this will be a moderate economic impact during construction as it is likely up to 40 workers will be employed/contracted at the site and a number of local sub-contractors would be utilized. With respect to the operation of the facility, it is unclear whether this will have any positive impacts on staffing levels at OPG’s Northeast Plant Group. However, it is an additional facility so at the very least it will have likely a minor and positive impact whether there be a slight increase in employees or simply a greater need for contractors and services.
4 2-19 1 The proposed undertaking is referred to as a "run-of-the-river" hydropower There are many different definitions of run-of-the- ERR, 2.3.2 development. The definition for Run-of-the-River in the glossary of the ERR river facilities. The specific instance in which the is "a powerplant that has no upstream storage capacity and must pass all term was used on page 2-19 was based on an early flows as they come". This definition seems to be inconsistent with the characterization by OPG. In order to avoid historical operation of Mattagami Lake Dam as a water control and storage confusion, OPG is proposing to delete the term “run- facility, as well as the proposed operation of holding back water during of-the-river” and merely state that: “Preliminary extended dry periods when only the minimum flow will be passed. assessments conducted by OPG indicate there is a Clarification is needed on how OPG categorizes hydropower plants into run- potential for a small hydroelectric development at this of-the-river, intermediate peaking and peaking facilities. This is an important site, consistent with how the River is currently definition and should be explained in the text or a reference to the glossary managed. made. 5 2-19, Is "(assuming a station flow capacity of 40-47 cms)" a typo on page 4-24? It The design flow range should be 40 – 47 cms. This Change made 4-24 is inconsistent with the design flow range of 40-55 cms described on page has been updated in the Report. throughout 2-19. 6 2-21 1 What will be the remaining flood capacity of the dam when sluices 1 and 2 The project description has been updated as follows. ERR, 2.3.2 are incorporated into the intake channel? “The discharge capacity of Sluices #3 - #6 will be 351 cms (close to the Inflow Design Flood (IDF) of 361 cms for 100 years). As a contingency for Dam Safety, the new intake includes a stop log sluice with an additional discharge capacity of 130 cms, which
Final A-2 March 2011 MATTAGAMI LAKE DAM GENERATING STATIONS – GOVERNMENT AGENCY COMMENTS ON MLD ERR AND TSDs
Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table brings the total discharge capacity to 481 cms and greater than the 1000 year IDF of 479 cms.”
7 2-21 2 Is there a back-up plan for working in the dry on the intake structures, should The Project Description has been revised to address ERR, 2.3.2 there be persistent leakage through the stoplogs, and/or spillover or this question. backwater from the other sluices? 8 2-31 Fig 2.14 Please enlarge this figure as it is difficult to read due to its size Yes this has been enlarged. Figure 2.14
9 3-15 6th line from bottom "(Figures 3.7 and 3.6:…)" should read "(Figures 3.7 and Correct and Completed. ERR, 3.3.2 3.8:…)". 10 3-20 Correct and Completed. ERR, 3.3.2 4th line in second paragraph "(Figure 3.7)" should read "(Figure 3.8)". 11 3-21, The minimum flow implemented for walleye spawning at MLD might vary Corrected and Completed ERR, 3.3.3.2 5-4 between 12-15 cms from year to year, depending on the observed and anticipated flow conditions each year, as per the current MRSWMP (2006). 12 3-34 4 Please change “Domtar” to EACOM as ownership has changed and the Corrected and Completed. ERR, 3.5.1 "Shining Tree Forest" no longer exists as it is now part of the Timiskaming Forest. Please refer to the Timiskaming Forest.
The portion of the Timiskaming Forest that is within the Timmins District is still locally referred to as the Shining Tree area. 13 3-34 5 Please change the reference from Pickerel to Walleye to reflect current Corrected and Completed. Change made wording. throughout 14 3-35 4 Please change the reference from the “District Land Use Guidelines” to the Corrected and Completed. ERR, 3.5.2. “Crown Land Use Policy Atlas.” District Land Use Guidelines are no longer the current direction, they were replaced by Crown Land Use Atlas policy reports in 2006. 15 3-37 3 It is only MNDMF that withdraws lands from mineral claim staking, MNR Acknowledged. However, the withdrawal has ERR, 3.5.2 makes the request to MNDMF. Note also the change from MNDM to already occurred. MNDMF. Ministry of Northern Development Mines and Forestry. 16 3-37 Add to Text There is no mention of camping as a recreational use in the immediate OPG and its consultants have not observed crown ERR, 3.5.2 vicinity of the dam at the portage trail and also at the southwestern corner of land camping but has revised the Report to indicate Kenogamissi Lake. that while this doesn’t occur immediately at the site of the GS, it occurs in the general vicinity.
Final A-3 March 2011 MATTAGAMI LAKE DAM GENERATING STATIONS – GOVERNMENT AGENCY COMMENTS ON MLD ERR AND TSDs
Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table 17 3-37 Add to Text This section should be consistent with other references in the report that This has been revised in the ERR. ERR, 3.5.2 state that Kenogamissi Lake has had a commercial whitefish fishery. 18 4-11, 5 Direct effects on benthic macroinvertebrates are only mentioned in Section Text has been added to the Aquatic TSD and ERR. ERR, 4.3.2 4-17 4.3.1 regarding Potential Construction Impacts. An additional consideration for benthic macroinverterates is the potential reduction in quantity of habitat during the summer low flow period (an operational impact). During any period that 2.8 cms is passed instead of inflow (i.e., when the generating station is shut down during dry periods), total benthic macroinvertebrate habitat will be reduced. While the impact on total benthic macroinvertebrate productivity is estimated to be small and would be difficult to detect amongst natural variability, a note on the potential effects is warranted. 19 4-12, References are made on these pages that should specify the Aquatic TSD. Corrected and Completed. Changes made 4-13 throughout 20 4-12 2 The ERR suggests that a silt curtain will not be needed during the Acknowledged. OPG has revised the TSD. ERR, 4.3.1.2 dismantling of the rock-filled wooden crib structure. MNR will review the need for a silt curtain during the permitting stage. 21 4-13 Section If the contractor’s final design has the potential to effect environmental This comment is acknowledged. Noted but no 4.3.1.2 components not specially assessed during the EA then additional change made. assessment of potential effects and mitigation may be required prior to approvals and permitting. 22 4-14 1 Where will the settling pond and/or filter bag be located during construction? When final stamped drawings are available (in Noted but no execution phase) we can determine exact location of change made. settling ponds and filter bags.
23 4-16, A comparison of Figures 4.5 and 3.15 indicates that the proposed riverbed Acknowledged. OPG has revised the TSD. ERR, 4.3.1.2 3-30, recontouring for the tailrace extension overlaps with the upper whitefish 2-27 spawning pool. What are the anticipated effects of the recontouring on the whitefish spawning habitat? 25 4-17; In the Aquatic TSD the word "amended" should be added to the second Corrected and Completed. Corrected Aqu sentence in section 4.2, to be consistent with Section 4.3.2 of the ERR. TSD 4-11 26 4-17 to Section “Users of the resource will not detect changes in water levels, river flows….” Users will not detect changes within Mattagami Lake, ERR, 4.3.2 4-25 4.3.2 is too general. In the interests of transparency for the public and given that Kenogamissi Lake, or other sections of the there will be changes in the magnitude, timing, duration, frequency and rate Mattagami River beyond the local study area. of change of flows, a table illustrating the pattern of flows modeled for the
Final A-4 March 2011 MATTAGAMI LAKE DAM GENERATING STATIONS – GOVERNMENT AGENCY COMMENTS ON MLD ERR AND TSDs
Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table unregulated system relative to the regulated system today versus the For EA purposes (provincial and federal) the proposed operations, using an appropriate time series, would tell the story proponent is required to assess the impacts of the more clearly as opposed to Table 4.2 There will be changes, regardless of proposed undertaking on the existing baseline whether the operations respect the WMP and the public needs to understand environment. The conclusion from the ERR referred the proposed hydrologic alterations and all predicted ecological alterations. to in the comment is based on an assessment of the impacts of the proposed operations of the The same needs to be done for the bypassed natural channel reach flow undertaking on the current baseline conditions, discussion. including the bandwidth imposed by the WMP.
However, OPG has updated this section summarizing the expected impact to flow once the proposed GS is operational.
27 4-17 Section The following sentence needs clarification: "Operation of the proposed GS Acknowledged. The ERR has been revised. ERR, 4.3.2 4.3.2 will respect the amended WMP, and therefore, users of the resource will not detect changes in water levels, river flow, or other aspects of the river environment". It is correct that the WMP will have to be amended to reflect the new minimum flow requirements. It is also correct that no change should be detectable in the adjacent reservoir water levels; however, some of the proposed changes in river flow within the near vicinity of the GS (as described in subsequent pages of the ERR) will probably be detectable by most observers at certain times of the year. Perhaps the sentence should specify "... users will not detect changes... within Mattagami Lake, Kenogamissi Lake, or other sections of the Mattagami River beyond the local study area". 28 4-18; 3 In third paragraph, should the reference to Figure 3.7 actually be a reference Corrected and completed. Corrected Aqu to Figure 3.6? through all TSD documents. 4-12 29 4-18 4 The flow of 0.2 cms was chosen because it was estimated that it would Based on site conditions it is highly unlikely that No change provide 11 cm depth at the bottleneck for fish passage (Transect S-3), and boulders will move at the site, however, should site made. that 11 cm would be sufficient to provide the necessary fish passage to and conditions change the configuration of the rockpool, from the pool. There are small boulders and cobble at Transect S3 that OPG will assess the situation to ensure that the might shift over the long-term. Since the objective is to maintain the ecological integrity of the pool is maintained. ecological integrity of the pool, if boulders and cobble shift, the measurements for compliance may have to shift accordingly in the future.
Final A-5 March 2011 MATTAGAMI LAKE DAM GENERATING STATIONS – GOVERNMENT AGENCY COMMENTS ON MLD ERR AND TSDs
Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table 30 4-19 The reference to Appendix B in the fourth paragraph should reference the Corrected and Completed. ERR, 4.3.2 Aquatic TSD. 31 4-24 Corrected and Completed. ERR, 4.3.2 In last paragraph Table 4.2 should be Table 4.4. 32 4-24 MNR agreed that if it could be demonstrated with field studies that a lower Acknowledged. No change magnitude of flow would adequately support the ecological integrity of the made. riverine system, MNR would support the use of that value as the prescribed minimum flow. This led to the flow demonstration exercise during which flows from 1.2 cms to 4.5 cms were compared, which ultimately led to the agreement of a minimum flow of 2.8 cms. 33 4-24 It should be noted that if the minimum rated capacity turns out to be 12 cms, The table has been revised. Table 4.4 the number of days that the facility has to pass the minimum flow of 2.8 cms Table has been changed in the ATSD as well. will be greater than was estimated for 8 cms. Since the rated capacity might Text further detailing the effect of flows on habitat range from 8-12 cms, depending on the final design of the plant, this section has also been added. of the report would benefit from the analysis being extended from 8 cms (best case scenario) to 12 cms (worst case scenario). 34 4-24, 2 The second paragraph on page 4-24 mentions that when the need to shut OPG will participate in whitefish monitoring as a Section 4.2 and 5-4 off the generating station and implement the minimum flow occurs, it will commitment through Water Management Planning. 4.3 of the Aquatic almost always occur sometime within July, August and September, when TSD and Section there is no spawning for any of the fish known to occur. This is likely true; Added paragraph on the impact of low flows upon 4.3.2 and 4.3.3 of however, the ERR should be clear that extended dry conditions can also whitefish spawning. the ERR. occur in October and might overlap with the beginning of the lake whitefish spawning period. With the proposed operating regime there will be flexibility Added paragraph in Monitoring Plan about the long- to reduce flows to 2.8 cms throughout the spawning period. From the same term monitoring of lake whitefish. historical flow dataset used in the ERR, it can be calculated that flows have not exceeded 8.3 cms for 20% of the time in the months of October from 1987-2006. In previous meetings and discussions, MNR and OPG have debated the potential impacts of low flows on whitefish spawning and reproduction success at Mattagami Lake Dam. In the March 3, 2010, meeting, OPG agreed to participate in an approximate 20 year monitoring study of the lake whitefish population in Kenogamissi Lake, to address MNR's concerns. The monitoring study was to be amended into the WMP as an Information Gap. MNR's agreement to move forward with the proposed minimum flow of 2.8 cms for the duration of the year outside of the walleye spawning, incubation, hatch and dispersal period, was conditional on OPG's participation in this study. The monitoring study will be a
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table condition of the LRIA Plans and Specs Approval for the final design of the generating station. A discussion about the potential impacts of low flows on whitefish spawning, the agreement for long-tem monitoring, and the associated WMP Info Gap is warranted in this ERR (Sections 4.3.2, 5.3.1 and 5.3.5 would be appropriate). 35 4-25 The reference to Appendix D in the second paragraph should specify the Corrected and Completed. ERR, 4.3.2 Aquatic TSD. 36 4-26 The reference to Appendix E in section 4.3.3 should specify the Aquatic Corrected and Completed. ERR, 4.3.2 TSD. 37 5-8 Based on the objectives from the WMP stated on p. 5-10 move the This flow should not be characterized as natural flow No change Minimum Discharge to the heading of Natural Flow Regime under Low regime minimum flow but rather a regulated made. Flows and clearly separate the 2.8 turbine flows and 0.2 bypass reach minimum flow. This is a regulated river. This is an flows. ecological flow for a regulated river system.
38 6-18 7 Check the title "Resource Liaison Officer" this may not be correct. This has been reviewed by Mattagami First Nation. No change The context refers to their individual not MNR’s. made.
39 6-19 6 OPG must meet the consultation requirements of the Environmental MNR’s perspective is acknowledged. No change is No change Assessment Report for the project, however the Crown has a duty to consult proposed to the ERR. made. drawn from federal case law which it cannot discharge to a third party and must consult on specific permits, approvals and authorizations. MNR was present at many meetings and open houses however they did not lead this consultation as it was the proponents, i.e. OPG's responsibility. Until the EA is complete and meets all of M.O.E.'s requirements we do not know if the project is viable, only then will MNR consult on their permits as required. It has been the experience of MNR that actual conditions at the time a permit is needed can change from what was anticipated at the writing of the ERR. 40 7-6 2 MNR and DFO have not agreed to issue permits later than September 15th. Discussed in Comment #1. Change made throughout 41 7-10 2 The MNR District Manager must be consulted on all road closures on Crown Corrected and Completed. ERR, 7.2.1 land. 42 7-16 Table 7.1 The Standing Advisory Committee makes recommendation to the local Acknowledged and noted but OPG anticipates that a ERR, Table 7.1 MNR District Manager as to the categorization. The categorization of the Minor Amendment is all that is required. amendment cannot be assumed before that review takes place. The reference should be to the Mattagami River Water Management Plan.
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table 43 7-16 In addition to the permits and approvals identified in Table 7.1, Location Corrected and Completed. ERR, Table 7.1 Approval will be required under the LRIA. 44 7-16 In addition to the permits and approvals identified in Table 7.1, a Work Corrected and Completed. ERR, Table 7.1 Permit to do work on shorelands or within a water body might be required under the PLA O. Reg 453/96. 45 7-17 Table 7.1 Fish Collection Permit should be changed to Licence to Collect Fish for Corrected and Completed. ERR, Table 7.1 Scientific Purposes. 46 G-2 Run-of-the-river -- where is this definition taken from? OPG acknowledges that this definition is confusing. Change made It has been deleted. throughout.
47 A-6 Photos 11 Is the flow information available for these 2 photos, if so please add them to Acknowledge and completed. The flow was 7 cms. No change and 15 the description. made. 48 This section will require more detail prior to S. 14 and 23.1 LRIA approvals. OPG does not know what Comment 307 of the draft No change Comment 307 of the draft PIP/ESR review described, in general, the PIP/ESR is and therefore does not know the basis of made. contents of a monitoring plan. While table 9.3 has identified the years of this Comment. sampling, there will need to be clearly stated monitoring objectives, identification of performance indicators and measurement endpoints, data That being said OPG is of the opinion that its collection methods and protocols and reporting requirements. The reporting environmental assessment as documented in the requirements should use the following framework to guide the Aquatic TSD and Environmental Study Report has assessed the existing ecological conditions and What was the ecological condition (status) before construction? potential impacts of the project and identified What is the potential degree of alteration in key ecosystem appropriate mitigation and monitoring measures to components posed by the planned development or redevelopment? address the impact. OPG recognizes that What is the potential impact to the ecological condition? construction and post-construction monitoring is to What measures are were predicted to mitigate the impact and assess the effectiveness of the mitigation strategies. maintain or restore the ecological condition? What is the effectiveness of the mitigation strategies? What is the effect of resulting tradeoffs? Aquatic TSD 49 3-8 Table 3.1 Reorienting the values in this table would make it more readable. This has been re-formatted. Aquatic TSD, Table 3.1 50 Apend 2 Fieldwork Substrate is misspelled in photo section, none of the tables are labelled, no We were unable to find where this comment No change Data title on photo page occurred. As the comment was not substantive in made. nature no change has been made.
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table 51 14 Nowhere is the flow of 4.5 m3/sec described as the initial starting point for G. Coker stated in the Ecological Flow Assessment No change the demonstration flows, there should be a reference to regulated flows for Report that the flow was initially lowered to “around 5 made. MLD and why demonstration flows were needed below 4.5 m3/sec. cms”. Once we measured it accurately, we knew this was in fact 4.5 cms. Then, everywhere in the document where the demonstration flow values were listed, they were noted as starting at 4.5 cms.
The range of flow (around 5 cms and lower) was chosen because it covered the range between the MNR’s preferred minimum flow of between 4 and 5, which was based upon some value from MNR’s natural flow analysis, and OPG’s proposed value of 2. While this is not stated explicitly in the Ecological Flow Assessment report, Appendix A of that report, which was the documentation of a meeting between Jamie Mucha and George Coker in which the basic parameters and methodology of the flow assessment were determined and agreed to ahead of time, reflects that understanding among the participants.
52 Apend C Transect What do the 3 points marked by an X with an associated value mean? There isn't These are velocity measurements (cm/s). No change Figures anything in a legend to indicate the significance of these points. made. Terrestrial TSD 53 4-3 Figure 4.1 Has the minimum and maximum temperatures been reversed in the legend? Yes. Corrected and Completed. Terrestrial TSD, Figure 4.1 54 4-24 In addition to the herpetofauna mentioned in the Terrestrial TSD, MNR Acknowledged. We will revise the Terrestrial TSD to Terrestrial TSD, occasionally receives reports of Snapping and Painted turtles in the indicate that: “MNR occasionally receives reports of 4.8 Timmins and Gogama areas. Both have been observed by MNR staff in the Snapping and Painted turtles in the Timmins and Grassy River watershed, which is a tributary to the Mattagami River. Gogama areas. Both have been observed by MNR Snapping turtles are a species of Special Concern under the ESA (2007). staff in the Grassy River watershed, which is a tributary to the Mattagami River. Snapping Turtles are a species of Special Concern under the ESA (2007) but Painted Turtles are "Not at Risk". Neither Snapping Turtles nor Painted Turtles were observed during terrestrial or aquatic field investigations at Mattagami Lake Dam. This is not surprising as the
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table proposed site of the GS would not be habitat generally suitable for turtles.”
55 4-2, 4-3 It appears that the minimum and maximum temperature titles are switched Yes. Corrected and Completed. Terrestrial TSD, in the table and in the graph. Figure 4.1 56 4-14 2nd paragraph refers to "Appendix 1, FID 66". Appendix 1 is not listed in Yes. Corrected and Completed. Terrestrial TSD, the Terrestrial TSD table of contents, but it is present at the end of the TSD, Checked untitled and embedded between Appendix A and B. It includes tracked throughout changes. 57 4-24, Table 5.1 should be "Table 4.7" in herpetofauna text. Table 4..should be Yes. Corrected and Completed. Terrestrial TSD, 4-26, "Table 4.8" in avifauna text. Other table references incorrect. 4 4-34 58 4-36 Table 4.10 (list of SARs "with ranges overlapping the study area") is missing Acknowledged. Corrected and Completed. Terrestrial TSD, a number of species from the 2010 Species at Risk list. These include, but 4.11 might not be limited to: Cougar (endangered), Whip-poor-will (threatened), Chimney Swift (threatened), Black Tern (special concern), Common Nighthawk (special concern), Olive-sided Fly Catcher (special concern). None of these species have documented occurrences near the MLD study area, but all of them seem to fit within the scope of this table. If the table is updated, the sentence, "Of the many terrestrial species that have been designated as endangered, threatened or of special concern, only ten have ranges overlapping the study area", should also be updated accordingly. In addition, the Great Gray Owl and the Red-Shouldered Hawk have been removed from the provincial list of species of special concern under the ESA (2007). 59 5-6 2 Corrected and Completed. Terrestrial TSD, fix the error message. 5 Socio-economic TSD 60 3-4 3 This is better referenced as the Crown Land Use Atlas, Policy Report Corrected and Completed. Socio-Economic G1813 (updated 2006). TSD, 3 ERR, 3.5.2 61 3-4 4 This policy report also refers to supporting a commercial fishery at the south Corrected and Completed. ERR, 3.5.2, end of Kenogamissi Lake. Socio-Economic TSD, 3
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table 62 Need to acknowledge that Kenogamissi Lake has supported a commercial Corrected and Completed. ERR, 3.5.2, whitefish fishery in the past. Socio-Economic TSD, 3 63 4.4 3 The Timmins District Manager must also be consulted. Corrected and Completed. Change made throughout 64 4.4 5 Change height from feet to metres. Corrected and Completed. Socio-Economic TSD, 4 Public Consultation TSD 65 5.9 new Should make reference to the information gap cited in the MRWMP as It is OPG’s position that this a WMP issue and not an No change priority #10 page that the studies done in this ERR fulfill some of information environmental assessment issue. OPG’s EA is made. gap knowledge. carried out according to the MOE ‘s Guide to Environmental Assessment for Electricity Projects (March 2001) and assessed the impacts of the Project accordingly. We anticipated that the information gaps identified for the purpose of the WMP will be addressed as required by that process.
The studies undertaken during the ERR looked at the minimum flow required for ecological requirements and did not address the wetted perimeter (and associated flows) required for walleye spawning. This information gap study (priority 10) is to revisit the 12-15cms minimum flow constraint for walleye spring spawning.
TRANSPORT CANADA COMMENTS 66 General Transport Canada is responsible for the administration of the Navigable Previous correspondence with respect to the “no Table 7.1 Comment Waters Protection Act (NWPA), which prohibits the construction or trigger” was an e-mail sent from Jennifer Hughes to placement of any “works” in navigable waters without first obtaining Gillian Macleod and Laurie Bruce dated August 1, approval. If any of the related project undertakings cross or affect a 2007. This e-mail has been provided again to potentially navigable waterway, the proponent should prepare and submit Transport Canada. an application in accordance with the requirements as outlined in the attached Application Guide. Any questions about the NWPA application Transport Canada should be aware that OPG has an process should be directed to the Navigable Waters Protection Program at existing dam in this location and a boom and other 1-866-821-6631 or [email protected]. Please note that structures have approval under the NWPA (Your File: certain approvals under the Navigable Waters Protection Act trigger the 8200-07-6279).
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table requirement for a federal environmental assessment under the Canadian Environmental Assessment Act (CEAA). The proponent may therefore wish It should be noted that OPG’s proposed undertaking will not limit or prevent boating as according to the It has been noticed in the Final Draft of the ERR, page 7-12 and 7-13: NWPA Application Guide. As this is the case, "Transport Canada has advised OPG that TC will not likely have a CEAA according to the Guide this is a Minor Work and trigger for this project. An approval under section 10(2) of the Navigable therefore does not require TC approval. Boating Waters Protection Act would be required to convert the existing water through the waterfalls is already restricted by the control structure, however this is not included under the Law List boom line and dam that currently exist and which are Regulations pursuant to CEAA, and therefore TC has no requirement to approved by TC. OPG will be enhancing the site by conduct an EA prior to issuing such an approval. Plans showing the providing improved signage for the portage around the proposed alterations would need to be submitted to the NWPA Office to Generating Station. initiate the approval process." as well as "Six copies of final plans will need to be sent to Transport Canada in the permitting phase of the project. This Discussions about the proposed project were would occur once OPG has fully accepted the final plans for the project (and previously held with Navigable Waters Protection they are also fully approved by MNR under the LRIA). OPG should review Officer, Rick Thomas and an e-mail from Rick dated with Transport Canada the proposed locations of: the portage; booms, October 29, 2007 has been re-sent to TC. His e-mail buoys, signage and other structures as indicated by TC". It would be useful indicates that the road crossing location of the portage to know if the NWP application for project review has been submitted is fine and attached Transport Canada’s already and who from the NWP or anyone else within TC has had considerations for a Portage crossing a road. He then correspondence with the proponent or anyone acting on behalf of the indicated that when the plans are finalized six copies proponent. Note that the EA and NWP offices within TC work separately should be sent in. and from different offices. At this point, OPG has a conceptual plan for the Generating Station. A detailed plan of the GS showing the proposed locations of: the portage; booms, buoys, signage and other structures as indicated by TC will be sent to TC when they are completed. This will occur after completion of the environmental assessment.
In order to provide for more fuller documentation, OPG is willing to indicate in the Environmental Review Report the following: “Because an existing structure is already in place and approved by Transport Canada under the NWPA and that the proposed undertaking is a minor undertaking and will not limit or prevent
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table boating, no approval is required from Transport Canada. OPG will have regard for Transport Canada’s considerations for Portage Crossing a Road, in design of the final facility.”
It should also be noted that this project meets TC’s definition of a “Minor Work” for “Aerial Cables” and will be built to the standard “CAN/CSA-C22.3 No. 1-06.”
ENVIRONMENT CANADA COMMENTS 67 Environment Canada General Comment: General Comment. Specific responses to specific comments are below. EC’s review specifically focuses on the consideration of potential effects of this project during its construction, maintenance and operation related to water quality, air quality and toxics management, migratory birds, and, species at risk. Please note that we have a regulatory interest in these factors as administrators of section 36 of the Fisheries Act, the Canadian Environmental Protection Act 1999, the Migratory Birds Convention Act 1994, and Species at Risk Act, respectively. We did not identify any substantive concerns pertinent to areas of our departmental mandate; however, we are of the opinion that more information could have been included in the assessment on potential effects due to: (1) disposal of waste rock from structure foundation and canal excavation - effects on the proposed disposal area, notably terrestrial vegetation and wildlife/migratory bird habitat; and, (2) burning of slash and other vegetation waste from clearing of work areas, notably the transmission line corridor - effects on air quality (smoke emissions) and water quality in receiving watercourses (due to alkaline ash runoff). Any appropriate mitigation and monitoring should also have been included to address any potential effects of the foregoing works and activities. Please note that EC typically recommends the following mitigation in regard to management of waste material, notably timber waste and waste rock.
Environment Canada's comments and recommendations are intended to provide expert support to project proponents and decision-makers, in
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table accordance with its program related responsibilities and associated guidelines and policies. These comments are in no way to be interpreted as any type of acknowledgement, compliance, permission, approval, authorization, or release of liability related to any requirements to comply with federal or provincial statutes and regulations. Responsibility for achieving regulatory compliance and cost effective risk and liability reduction lies solely with the project proponent.
68 General Waste and Wood Waste OPG agrees with EC on the effort to minimize No change Avoid or minimize vegetation clearing and open burning vegetation clearing and open burning. made. Do not burn waste plastics, rubber, used engine oil waste or chemically treated/contaminated materials OPG will require the Contractor to follow Applicable Chip and compost waste timber slash, utilize select materials for Law in managing waste, specifically, Ontario Reg. wildlife habitat creation 347 - General Waste Management, which regulates Burn timber only when it is dry and configure timber slash piles to waste management and disposal. With respect to promote good internal air circulation and rapid burning slashing and timber disposal, OPG will in addition Carry our burning only under favourable ambient air quality and require the contractor to also follow the requirements meteorological conditions, for example avoid periods when of the Forest Fires Prevention Act. temperature inversion and/or smog conditions are likely to occur burn timber only when there is sufficient wind speed to adequately facilitate mixing and dispersion of smoke avoid high wind condition that could spread fire avoid burning immediately after, or during, substantive precipitation events Identify locations of sensitive ecological and human receptors in proximity to proposed burn location Maintain an adequate buffer between burn area and sensitive ecological and human receptors Avoid burning at locations, and during conditions when sensitive receptors downwind are potentially impacted Monitor smoke plume density and direction and take any required actions to minimize impacts on sensitive receptors Apply fine water mist to dense smoke plumes potentially affecting sensitive receptors
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table Prepare a contingency plan to address excessive smoke and out of control burns 69 Waste Rock At this point OPG does not anticipate having a waste No change rock stockpile area, but should it be needed, it will made. If waste rock will be disposed of at a waste rock stockpile area, the adhere to the recommendations of EC. footprint and height of the rock pile should be minimized. In order to provide a viable growing media for vegetation in the waste rock disposal area, the final upper layer of the waste rock pile will have to be covered with an adequate depth of topsoil sufficient to retain moisture levels. A minimum topsoil depth of what was existing in the area originally, or preferably 30 – 40 cm, should be maintained over a layer of finer well graded fill material - which should also be added prior to topsoil in order to produce a deeper and more organic soil for vegetation growth. To further retain topsoil, fill material and soil moisture, an engineered membrane should be installed prior to placing the fill material. The proposed surface drainage of the final waste pile should be configured so as to maximize water retention and minimize surface erosion. Also, in order to minimize erosion of final cover and restore lost habitat, native vegetation species indigenous to the area and tolerant to expected moisture conditions (in the cover soils) should be selected for planting.
FISHERIES AND OCEANS CANADA COMMENTS
71 Will the bottom and sides of the intake canal consists of blasted bedrock The bottom and sides of the intake canal will be No change to when done or will this be a concrete structure? concrete structures. Report.
72 Will any water crossing or in-water work be required for the installation of No. One creek will need to be crossed by the No change to the transmission line? transmission line but it can be approached from Report. either side. No new water crossing or in-water is proposed. If a crossing is required, the contractor will need to obtain approval for it from the Ontario Ministry of Natural Resources.
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table 72 What will be the width of the tailrace at the high water level where is joins OPG anticipates it will be approximately 20 meters. No change to the river (what length of shoreline will be removed for it's installation)? Report.
73 Will a silt curtain be sufficient or work in-stream on the cobble bottom at the The use of a silt curtain has been proposed at MLD No change site? I believe there have been some problems with a similar application at based on the specific conditions at this site. For made. Lower Sturgeon. MLD, most of the tailrace will be constructed in the dry, behind the shoreline berm that is proposed to protect the work area from flooding over the bulk of the construction period. This shoreline berm is above the normal water level, and so when construction progresses to the point that it must be removed, its removal will be timed to occur at the low flow period so it can removed in the dry. During the low flow period, flows in the river at the tailrace can be further reduced through control at the upstream dam, allowing the final excavation and contouring of the tailrace to blend with the riverbed, to progress as far as possible in the dry. Though the silt curtain will be installed prior to the shoreline berm being removed, during low flow only the final portion of the tailrace will be constructed in-water. Once in-water construction occurs, water enclosed within the silt curtain should be pumped to a treatment facility (settling pool and/or filter bag) to encourage any leakage around the silt curtain to occur in the inward direction, rather than outward. The substrate in the River appears to be mostly boulder, cobble, and gravel, and will not be a significant source of heavier fine sediments that may deposit on downstream river substrates. It is unlikely that all releases of turbid water can be avoided completely. However, the flowing water of the river will convey any released turbid water quickly downstream to the lake where it will be diluted, doing no significant harm to river or lake substrates. Regardless, it is believed that the use of a silt curtain, under the conditions detailed
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table above, will result in less sediment loss to downstream habitats, and a significantly shorter in- water work period, then what would occur if a cofferdam was utilized for the full extent of the tailrace excavation into the river.
75 I don't remember discussing the relocation of a rock filled crib during any of The rock filled timber crib was built in 1914, the Aquatic TSD, our meetings. I will need dimensions and drawings of the crib and location centre six sluices were demolished in 1921 and the 3.4.1 information of where the material will be deposited (locations, substrates, east and west abutments were demolished to about depths, etc). The report states that use of the crib by fish seems unlikely EL 326.5. The remaining small section of the west but doesn't describe any field investigations to prove this or give any abutment is about 4.5m (15ft) wide, 12m (40 ft) long reasoning why. and 1.5m high and will be removed and deposited to an approved disposal site by the contractor. Since this rock-filled crib likely provides habitat structure for some species of fish, a deposit of equal size, of similarly sized material, will be placed upstream from the proposed intake. To improve the utilization of this habitat by fish, this new habitat should be located in deeper water so that it remains submerged during the late winter drawdown of Mattagami Lake. Some additional habitat description has been added to the Aquatic TSD.
76 Can figure 3.15 be labelled like 3.14 with Areas A, B, C, etc.? Completed. Aquatic TSD, Figure 3.15 77 With reference to blasting per DFO Guidelines (pg 4.4), it should be noted Acknowledged. No change to the somewhere for the contractor that if they cannot complete the blasting per Report. the guidelines they should seek at Section 32 authorization under the Fisheries Act for killing fish by means other than fishing. This would require completing a federal environmental assessment. 78 On page 4.6 it states that construction of the tailrace channel is ultimately With respect to the construction of the tailrace No change to the the responsibility of the contractor. With all the discussion regarding angling channel all the design and mitigation considerations Report. the tailrace to minimize the impact to adjacent spawning habitat (suitable identified in the ERR and any relevant permits must flows and velocities), I don't feel this is a suitable statement for OPG to be adhered to by the constructor. make. I wouldn't want to see 'during construction' changes or project design changes on the fly that would result in impacts. Decisions are being made
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Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table based upon the conditions described in the modelling, if these conditions are not reflected on site, it could make decisions invalid.
79 Discussion on page 4.13 seems pretty sparse considering all of the OPG has specifically calculated that 6% of the Aquatic TSD, discussions that occurred regarding potential impacts to spawning habitat. walleye spawning habitat and something less than Section 4.2 Clear indication of the mitigation of impacts to the spawning habitat should 50% of the whitefish spawning habitat between the be included in here. It is not clear how much spawning habitat is being Dam and Kenogamissi Lake is in what OPG has affected or how much of the total area this is. Quantitative information identified as “Area B”. This is the Area in which the would be helpful here. discharge from the proposed tailrace will change the velocity and orientation of the existing flow patterns. As such, OPG has identified a specific quantitative area that will be impacted. In the following two paragraphs OPG goes on to describe the mitigation measures to address the impacts.
MINISTRY OF THE ENVIRONMENT (MARCH 2011) 80 For the bypass reach, a minimum flow of 0.2 cms was proposed to maintain The sole purpose of the 11 cm of water depth is a Aquatic TSD the viability of fish habitat in a “bedrock pool” located 40 m upstream of the mitigation measure to maintain habitat connectivity bridge, and to maintain water quality as well as a maximum water depth of between the bedrock pool, located downstream of 11 cm at the outlet of the pool. This will provide habitat connectivity with the Mattagami Lake Dam, and downstream habitats, downstream aquatic habitats. More information on the hydraulic analysis in once the proposed GS is operational. The support of this minimum flow and depth needs to be provided. associated estimate of 0.2 m3/s flow was a bi-product of the original assessment, but in fact has become The minimum flow considered during visual assessment was 1.2 cms rather immaterial to the outcome of this mitigation measure, than the 0.2 cms. Any data from that visual assessment would be helpful. and therefore no record of that calculation has been maintained or presented in the EA reports. The subsequent calculations that showed 0.2 cms flow would result in a water depth of approximately 11 cm at the outlet of the pool to maintain The following background series of events will connectivity of the bedrock pool to habitats downstream of the road bridge illustrate this. Habitat in the bedrock pool (see photo need to be provided. below) was examined and was found to be utilized by apparently small numbers of logperch (Percina It was noted in the report that a HEC-RAS hydraulic model was set up for caprodes), and does not provide critical habitats for the study reach. Perhaps that model could be used to demonstrate that the any fish species. Nevertheless, OPG, MNR, and 3 0.2 m /s bypass flow would be sufficient. DFO determined that the ecological integrity of the pool should be maintained, and that this could be accomplished by maintaining connectivity with
Final A-18 March 2011 MATTAGAMI LAKE DAM GENERATING STATIONS – GOVERNMENT AGENCY COMMENTS ON MLD ERR AND TSDs
Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table downstream habitats, and keeping some flow passing through the pool so that stagnant water conditions did not develop. The MNR biologist (Jamie Mucha) and OPG biologist (George Coker) met on-site and examined the area downstream of the bedrock pool (see photo below), and determined that a maximum cross-sectional depth of about 10 cm of water was required to maintain fish passage between the bedrock pool and downstream aquatic habitats. It was agreed between MNR and OPG that the 10 cm of depth would provide adequate fish passage, and the flow required to do this would keep the water in the pool from becoming stagnant. Subsequently, for the purpose of assessing the impact that providing flow to the bedrock pool would have upon the economics of the GS, as well as in the design of a delivery system for the required flow, OPG estimated that approximately 0.2 m3/s would provide a water depth of approximately 10 to 11 cm at cross section S-3 (see photograph). From this point onward, OPG targeted a rounded number of 11 cm as the outlet depth to be maintained. In examining the practicalities of delivering the water required to maintain a depth of 11 cm at the pool outlet, OPG water resources and engineering staff realized that the construction and maintenance of a delivery system for 0.2 m3/s of flow, as well as the required compliance monitoring for that flow, was technically difficult due to the site characteristics and the cold winter climate (ice). Since the goal of the mitigation flow was to maintain a depth of 11 cm of water at the pool outlet, OPG proposed that the delivery and compliance monitoring of this flow could simply be accomplished by monitoring the water level in the pool that would be associated with the outflow depth of 11 cm. Therefore, as long as the
Final A-19 March 2011 MATTAGAMI LAKE DAM GENERATING STATIONS – GOVERNMENT AGENCY COMMENTS ON MLD ERR AND TSDs
Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table pool water level is maintained at or above some level (to be field-determined during construction), the outlet water depth of at least 11 cm, as well as flow through the pool to prevent stagnant water conditions, will be ensured. This approach has been discussed with the MNR, and it has been agreed that this will be the method used to ensure the ecological integrity of the bedrock pool going forward.
In summary, the flow of 0.2 m3/s originally determined by OPG was an estimate for their own purposes, and the need of a more precise flow calculation was not required once the method of measuring and monitoring compliance was determined. The resultant system of monitoring compliance that has been agreed upon by the MNR and OPG, will maintain the ecological integrity of the bedrock pool without requiring the measurement of flow.
No visual flow assessment was presented at that magnitude of flow due to limitations of the flow regulating structure. This is correct. As noted below, 1.2 m3/s was the lowest flow attainable due to the limitations of the log operation and leakage from the Dam.
With respect to the visual assessment the MOE was sent a relevant photograph and the following relevant text was provided below.
As it was a visual assessment, there is no data, other than a series of photographs at different flows. The following photograph shows the configuration of the pool and outlet at 1.2 m3/s, which was the lowest flow possible from the upstream dam, as well as the location of cross section S-3 where a minimum of 11
Final A-20 March 2011 MATTAGAMI LAKE DAM GENERATING STATIONS – GOVERNMENT AGENCY COMMENTS ON MLD ERR AND TSDs
Comment Paragraph/ Pg# Comment or deficiency Disposition Section # # Figure/Table cm of water depth will be maintained. The measurement of cross-sections shown in the photograph were not originally undertaken for the purpose of flow calculation, but were extracted from one of the initial site surveys conducted in 2006.
The HEC-RAS hydraulic model was developed to model the flows downstream of the road bridge, where the tailrace is proposed to enter the river. The morphological character of the river in the area for which the model was developed is completely different than the upstream section of river where the water depth of 11 cm will be maintained to ensure the ecological integrity of the bedrock pool. Depth, width, slope, substrate, and flow volumes, are all completely different, and so the HEC-RAS model, as constructed, is not appropriate for this upstream area.
Final A-21 March 2011