For the Development of the Mattagami Lake Dam Generating Station
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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. Final ES-2 November 2010 Environmental Review Report For The Development Of The Mattagami Lake Dam Generating Station 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