BRADFORD ISLAND SERVICE BUILDING PRQ SWITCHGEAR UPGRADE

30-JUL-24: The purpose of this Amendment is to extend the Period of Performance and extend the proposal due date to 11:00 A.M. on 14-AUG-2024. See Summary of Changes. All other terms and conditions remain unchanged.

23-JUL-24: The purpose of this Amendment is to provide revised draw ings due to a bidder inquiry. The proposal due date and time has been extended to 11:00 A.M. on 31-JUL-2024. See Summary of Changes. All other terms and conditions remain unchanged.

Q: Sheet ED101 show s existing duct back w ith cables 03, 04, 14, & 17 & E101 show s new duct bank w ith 03, 04, 09, 07, 38, & 39 (07, 38 & 39 are listed as spare) detail A5 on sheet E-108 show s 1 of the 6 conduits as spare and a Fiber and a Phone in the other tw o conduits. Are the fiber and phone lines to be removed? If not removed w hat how long can they be out of service?

A: The phone line and f iber are to remain as part of the existing duct bank. If the optional CLIN is executed, the new duct bank w ill need to go from CV4 to HHPR1 instead of intercepting the existing duct bank outside of CV4, therefore all 6 conduits w ill enter CV4 w ithout having to take the phone line and fiber out of service. This change w ill be reflected in a forthcoming amendment.

03-JUL-24: The purpose of this Amendment is to extend the solicitation due date to 11:00 A.M. on 24-JUL-2024. See Summary of Changes. All other terms and conditions remain unchanged.

27-JUN-24: The purpose of this Amendment is to add Reference Drawings that were inadvertently left out of the solicitation package. See Summary of Changes. All other terms and conditions remain unchanged.

25-JUN-24: The purpose of this Amendment is to update the Bidder Inquiry key. See Summary of Changes. All other terms and conditions remain unchanged. Project Background. The Bradford Island PRQ Substation is supplied by two underground 13.8kV medium voltage feeders from an intertie in the High Voltage Cable Vault 11 (HVCV11) located in the South Spillway Tower.

The intertie feeders are connected to the power sources from both Powerhouse 1 and Powerhouse 2 for redundancy and each of the two PRQ feeders are tapped off the intertie using 600A dead break elbow junctions in the HVCV11. From the South Spillway Tower HVCV11, the two PRQ feeders go through an underground duct bank to the Bradford Island Service Building electrical room where PRQ Substation resides.

The Bradford Island Service Building electrical room measures 22 feet by 24 feet housing two disconnect switch cabinets, two 1000kVA 3?phase 13.8kV to 480V transformers and the switchgear cabinet sections. The electrical room housing the equipment is operating in a non?controlled environment with higher temperature and humidity than industry standards.

Present day switchgear and associated equipment have sensitive electronic equipment, which requires a specific operating temperature threshold to function accurately. The electrical room is currently cooled by two powered exhaust units located in the attic space where outside air is supplied through fans and filtered louvers located in the exterior doors. The fans are controlled by a thermostat inside the electrical room.

The PRQ Substation supplies power to the pump house fire system, the shelter building equipment and five other 480V panelboards within the Bradford Island Service Building. The equipment using the supplied power are 120V and 480V receptacles, lighting panelboards, various saws and grinders, various cranes, fans and heaters, and other numerous daily computing, telecommunication, and maintenance equipment requiring power to support the engineering and service departments.

The objective of this project is to replace the existing PRQ Substation with new 1500kVA transformers, 8 section switchgear and associated electrical protection equipment. This will entail relocating the transformers and associated electrical protection equipment to the parking lot area right outside of the existing electrical room. Completion of this work will meet the criteria and constraints as defined in the Phase 1A Report. Project Scope. The following information represents the project objectives:

1. Replace the existing 480V switchboard and station service transformers located in the Bradford Island Service Building.

2. Relocate the new transformer disconnect switches and (2) 1,500 kVA transformers directly outside the existing electrical room.

3. The new 480V switchgear and associated equipment will be housed in the existing electrical room.

4. Provide an exhaust fan or AC system to provide cooling for the electrical room.

5. Provide panic hardware for existing electrical room doors, fire stopping for all conduit penetrations through rated walls, fire extinguishers, and emergency lighting as required for life safety code compliance.