Auld's Cove Transmission Project
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AULD’S COVE Nova Scotia Power Incorporated TRANSMISSION PROJECT Environmental Assessment Registration Document March 4, 2016 Auld’s Cove Transmission Project 2015 Executive Summary Nova Scotia Power Inc. (NSPI) is proposing to construct a new transmission line crossing over the Strait of Canso at Auld’s Cove. The project will involve a physical separation of the 345kV and 230kV lines which currently share the existing double circuit towers at Auld’s Cove. The separation of the two lines will protect the system against a potential common tower fault such as a lightning strike, which could create electrical instability with the remaining transmission system. In addition to increasing reliability and protecting the electrical system in Nova Scotia, the development of a new crossing will also increase available capacity for energy from Cape Breton and the Maritime Link, to help NSPI meet provincial renewable energy targets, balance wind generation and strengthen grid connectivity. The proposed new transmission line crossing, with associated suspension and anchor towers, will be constructed approximately 45 m south of the existing towers. The project scope involves the construction of six foundations and towers total (three on either side of the Strait) and the installation of two circuits (six wires) similarly configured as the existing crossing. The Project is considered a Class 1 undertaking under the Nova Scotia Environmental Assessment Regulations and as such, requires a registered Environmental Assessment as identified under Schedule A of the Regulations. The Environmental Assessments and the registration document have been completed according to the methodologies and requirements outlined in the “Proponent’s Guide to Environmental Assessment” (Nova Scotia Environment 2001, updated 2014) and accepted best practices for conducting Environmental Assessments. The goal for completing the environmental assessment is to identify potential Valued Ecosystem Components (VECs), determine what effects the Project may have on each VEC and develop mitigation techniques that will eliminate, reduce or control any adverse environmental effects. Various environmental studies and considerations are required to support the Environmental Assessment. Special focus component studies and considerations were completed for the following VEC’s: • Avifauna; • Cultural and heritage resources • Archaeological resources • Wetlands and watercourses 1 Auld’s Cove Transmission Project 2015 • General habitat • Marine benthic habitat and fisheries • Significant habitats and rare species Additional VEC’s that have been considered during the assessment process are: • Terrestrial flora • Terrestrial fauna • Visual aesthetic • Geophysical environment • Atmospheric environment • Economy • Land use and value • Recreation and tourism • Human health Based on the data collected during the component studies and the research conducted for each of the respective VECs, the proponent used the data to develop constraints mapping to ensure, to the extent possible, that avoidance was the first consideration. This data was further used to determine reasonable mitigation strategies to further lower the potential impacts to VECs. The vast majority of the potential effects on the VECs evaluated were determined to have low to no residual effects based on the activities surrounding the construction, operations and maintenance and decommissioning of the project. Potential impacts on VECs that may result in residual effects will be lowered to an acceptable level with the deployment of appropriate mitigation, best management practices and follow up programs. 2 Auld’s Cove Transmission Project 2015 Table of Contents 1 Project Information ............................................................................................................................... 7 1.1 Proponent Description and Background ....................................................................................... 7 1.2 Purpose of the Project .................................................................................................................. 8 1.3 Regulatory Framework .................................................................................................................. 9 1.4 Structure of Document ................................................................................................................. 9 1.5 Investigators and Authors ........................................................................................................... 10 2 Project Description .............................................................................................................................. 10 2.1 Project Overview ......................................................................................................................... 10 2.2 Geographical Location ................................................................................................................ 11 2.3 Project Activities ......................................................................................................................... 13 2.4 Project Construction Schedule .................................................................................................... 18 3 Project Scope and Methodology ......................................................................................................... 19 3.1 Assessment Scope ....................................................................................................................... 19 3.2 Assessment Boundaries .............................................................................................................. 20 3.3 Assessment Methodology ........................................................................................................... 21 3.4 Valued Ecosystem Components (VEC’s) Selection ...................................................................... 22 4 Key Components and Evaluation ........................................................................................................ 23 4.1 Avifauna ...................................................................................................................................... 24 4.1.1 Overview ......................................................................................................................... 24 4.1.2 Field Surveys .................................................................................................................... 24 4.1.3 Discussion of Results ....................................................................................................... 49 4.1.4 Effects and Mitigation ..................................................................................................... 50 4.2 Cultural and Heritage Resources................................................................................................. 54 4.2.1 Archaeological Resource Impact Assessment ................................................................. 54 4.2.2 Cultural and Heritage Resources Effects and Mitigation ................................................ 56 4.2.3 Mi’kmaq Ecological Knowledge Study (MEKS) ................................................................ 57 4.3 Freshwater Environment and Terrestrial Habitat ....................................................................... 58 4.3.1 Wetlands and watercourses............................................................................................ 58 3 Auld’s Cove Transmission Project 2015 4.3.2 General Habitat ............................................................................................................... 61 4.3.3 Effects and Mitigation ..................................................................................................... 61 4.4 Marine Environment ................................................................................................................... 61 4.4.1 CRA Fisheries Assessment ............................................................................................... 62 4.4.2 Habitat ............................................................................................................................. 64 5 Alternatives to the Project .................................................................................................................. 66 5.1 Overview and Evaluation ............................................................................................................ 66 6 Additional Considerations ................................................................................................................... 68 6.1 Terrestrial Vegetation ................................................................................................................. 68 6.2 Terrestrial Fauna ......................................................................................................................... 69 6.2.1 Significant Habitats and Rare Species ............................................................................. 70 6.3 Geophysical Environment ........................................................................................................... 71 6.3.1 Effects and Mitigation ..................................................................................................... 72 6.4 Atmospheric Environment .......................................................................................................... 73 6.4.1 Effects and Mitigation ....................................................................................................