Topic:"Infrastructure Planning" in M13125

REDACTED CI 49595 Page 2 of 6 REDACTED (CONFIDENTIAL INFORMATION REMOVED) precision which resulted in taking the unit offline. The deteriorated and cracked draft tube access hatch presents an additional reliability and maintenance concern....

AI summary The document discusses the deteriorating condition of the Tusket Hydro System, including cavitation damage and reliability concerns, and the need for increased generating capacity to reduce spill operations and improve environmental and fishery outcomes. It also highlights the importance of the project for employee safety and compliance with environmental regulations.

Why do this project now? Unit 1 has been offline since 2020 due to mechanical and electrical component conditions. This investment has been deferred to reprioritize other higher priority, higher generation, units requiring overhauls that a...

AI summary Unit 1 has been offline since 2020 and requires refurbishment to support the Tusket Main Dam project and ensure operational reliability. NS Power plans to complete the overhaul during an outage to reduce costs, improve flexibility, and avoid future risks. The project is being done concurrently with Unit 1 generator refurbishment for efficiency.

Why do this project this way? Refurbishment of this unit through the replacement of identified worn components represents the lowest-cost approach for achieving the intended project scope, considering both the current condition of the comp...

AI summary The refurbishment of Tusket Hydro Unit 1 through component replacement represents the lowest-cost solution for achieving project goals, preserving reliability, and enhancing environmental performance. The overhaul includes replacing worn turbine and governor components, using modern materials to reduce environmental risks and maintenance needs, and restoring the unit to modern standards while maximizing asset life and operational performance.

Document No: XXX-XX-XXXX-XXXX Project Cost Estimate Input Checklist and Maturity Matrix Hydropower Required fields: Estimate Classification Project Name: HYD TUS 1 Overhaul Started or Preliminary Class 5 Class 4 Class 3 Class 2 Class 1 Mat...

AI summary This document outlines a project cost estimate input checklist and maturity matrix for the HYD TUS 1 Overhaul hydropower project. It details the project's scope, capacity, location, requirements, technology selection, strategy, and planning, with various levels of definition and maturity.

Technical Deliverables: - Not Required (NR): Deliverable may not be required for all estimates of the specified class, but specific project estimates may require at least preliminary development - Started (5): Work on the deliverable has b...

AI summary The document outlines the classification of technical deliverables for hydropower projects, detailing the stages of development and key components of hydropower facilities, including reservoir preparation, principal structures, and environmental mitigation features.

CI 49595 Attachment 1 Page 10 of 28 REDACTED (CONFIDENTIAL INFORMATION REMOVED) Governor Linkage / Quadrant shaft - Governorshaft concrete pedestal on the left side floor of the scroll case looking upstreamwas inspected. There was excessiv...

AI summary The text describes maintenance and repair work on a hydroelectric unit, including issues with the governor linkage, quadrant shaft, and draft tube door. Repairs involved epoxy, anchors, and adjustments to address excessive movement and wear. The draft tube door shows signs of erosion and cracking.

CI 49595 Attachment 1 Page 20 of 28 REDACTED (CONFIDENTIAL INFORMATION REMOVED) Oil Pots and Covers for bearings: Unit 1 has a cascading oil system powered by a shaft driven oil pump with internal cooling coil. Almost every piece of pipe w...

AI summary The text discusses significant oil leaks in Unit 1 of Tusket, including a cascading oil system with internal cooling coils, leaking pipes, and poor sealing on bearing covers and Kaplan Oil head piping. The aging infrastructure requires replacement and improved sealing methods.

CI 49595 Attachment 1 Page 24 of 28 REDACTED (CONFIDENTIAL INFORMATION REMOVED) Cooling water intake- Needs modifications to the intake, there is no screen on the outer part of the plant, inside trash racks, outside headgates. These intake...

AI summary The document mentions that the cooling water intake requires modifications, as there is no screen on the outer part of the plant, leading to blockages by minnows during the winter. This issue affects the intake system's functionality.

Notes: 1. Major Component Materials (Runner Castings)

AI summary The text discusses major component materials, specifically runner castings, which are relevant to infrastructure planning and power generation.

REDACTED CI 49595 Attachment 6 Page 2 of 22 REDACTED (CONFIDENTIAL INFORMATION REMOVED) File No: 251166 a construction joint between the concrete block supporting the quadrant shaft and the main concrete pedestal. This construction joint h...

AI summary The document describes structural issues found in a concrete block supporting a quadrant shaft, including separation from the main pedestal, voids, cracks, and water leakage in the scroll case. These conditions suggest potential structural and integrity concerns.

4.1. Repairs of Existing Concrete The existing steel frame should be removed from the concrete block. Harbourside has identified multiple locations where the existing concrete must be repaired due to voids or large cracks observed in the c...

AI summary The document discusses repairs to existing concrete blocks, noting the need to remove unsound concrete and repair voids and cracks. Harbourside proposed both concrete and steel repair options, but recommends proceeding with concrete repairs only due to the existing need for concrete repairs even if a steel option is selected.

4.2. Encasement of The Existing Concrete Block Harbourside proposes encasing the existing concrete block supporting the quadrant shaft with new reinforced concrete around the entire perimeter. This concrete encasement would be approximatel...

AI summary Harbourside proposes encasing the existing concrete block supporting the quadrant shaft with new reinforced concrete around the entire perimeter. This encasement would be approximately 300mm thick and would include rebar dowels anchored into the existing structure to ensure load transfer and reinstate a rigid anchor point for the quadrant shaft.

4.3. Water Control Before commencing any repairs, water control must first be established. Harbourside carried out a site visit when the scroll case was dewatered, and it was observed that some water was still present on the scroll case fl...

AI summary Before repairs can begin, water control measures must be implemented. Harbourside observed water leakage from cracks in adjacent scroll cases and the stop logs. They propose using sandbags and a submersible pump to manage water, especially during concrete work.

REDACTED CI 49595 Attachment 6 Page 15 of 22 REDACTED (CONFIDENTIAL INFORMATION REMOVED) 251166_SVR_2025-08-07.docx PREPARED BY: Carson MacKay Weather & Temperature Location Site Visit Date (yyyy-mm-dd) 2025-08-07 Sunny, 25°C. Tusket Power...

AI summary This document is a site visit report for the Tusket Powerhouse Scroll Case Concrete Repair conducted on August 7, 2025, with weather conditions being sunny and 25°C. The visit was prepared by Carson MacKay and took place from 10:00 AM to 1:30 PM.

REDACTED CI 49595 Attachment 6 Page 16 of 22 REDACTED (CONFIDENTIAL INFORMATION REMOVED) - Harbourside observed the interior walls and floor of the scroll case, the main concrete pedestal supporting the draft tube, and the concrete block t...

AI summary The text describes observations made by Harbourside regarding structural and water leakage issues in a concrete block and surrounding areas of a scroll case. Issues include separated construction joints, voids, cracks, delamination, and water accumulation, with NSPI expressing concerns about the repair and desiring a more robust solution.

3.11 Throat Ring - Review inspection data, propose repair options, and prepare final design. - NSPI will provide inspection data including, but not limited to the following: - o General condition of throat ring and dimensions - o Material...

AI summary NSPI will provide inspection data on the throat ring, including its condition, dimensions, material, and remaining steel thickness, to support the review and proposal of repair options and final design.

DESCRIPTION: This project is for the refurbishment of Tusket Unit 1 generator rotor and stator. The scope includes a complete stator rewind, replacement of rotor pole insulation and associated rotor refurbishment, replacement of deteriorat...

AI summary This document describes a project to refurbish the generator rotor, stator, and exciter at Tusket Unit 1, located at the Tusket Hydro Station. The refurbishment includes rewinding the stator, replacing insulation and electrical components, and testing. The project aims to improve reliability, reduce electrical faults, and extend the unit's operating life. The station has been in service since 1929 with no major refurbishments since 1930.

Why do this project now? NS Power intends to complete construction of the Main Dam with the Lake Vaughan Reservoir remaining within its regulated operating range. This will require the support of the generating units and it is critical to...

AI summary NS Power plans to complete the Main Dam construction and the Unit 1 turbine overhaul concurrently to ensure operational stability, reduce risks, and minimize lifecycle costs. This approach avoids future disruptions, improves maintenance flexibility, and enhances the reliability of the Tusket Powerhouse.

Why do this project this way? Refurbishing the stator, rotor, and exciter as a single electrical project addresses the primary age-related risks associated with Unit 1's original 1929 generator components. Completing all major generator wo...

AI summary Refurbishing Unit 1's generator components as a single project improves reliability and reduces future outages. Reusing existing rotor poles and refurbishing them off-site is more economical. Combining this with turbine rehabilitation maximizes lifecycle value and extends asset life.

Document No: XXX-XX-XXXX-XXXX Project Cost Estimate Input Checklist and Maturity Matrix Project Code of Accounts Defined (D) NR P D D D Project Schedule Defined (D) NR P D D D Risk Register Defined (D) NR P D D D Stakeholder Consultation/E...

AI summary The document outlines a checklist and maturity matrix for project cost estimate inputs, detailing the status of various project components such as the project code of accounts, schedule, risk register, and technical deliverables. Several items are marked as not applicable or incomplete, indicating varying levels of development across different project aspects.

Technical Deliverables: - Not Required (NR): Deliverable may not be required for all estimates of the specified class, but specific project estimates may require at least preliminary development - Started (5): Work on the deliverable has b...

AI summary This section outlines the classification of technical deliverables for hydropower projects, highlighting the key components and features involved in the development of such facilities, including reservoir preparation, river management, principal structures, and environmental mitigation measures.

Voith Hydro Customer: Nova Scotia Power KV: 6600 Site: Tusket Rating: 900 KVA Unit: 1 Number of Slots: 0 Job Number: 0 Sidepacking Type: 0 Cuts Ref: 0 Coil Type: Multi Turn Work Scope: Test and Inspect Insulation: 0 Machine: Vertical STATO...

AI summary The document outlines an inspection checklist for a generator unit at the Tusket site, operated by Nova Scotia Power, focusing on the stator core, fingers, endplates, core studs, and frame joints. The inspection details the condition of various components and includes notes on observations such as 'some wave' on the back side of the core.