RFP 2023 QA

Based on how the RFP was issued, AES cannot accept an offer just for the HV construction scope. Those services will be required to be performed by the company awarded through this RFP process.

1. Collector Substation (34.5/345 kV) for the project will be included as part of the Contractor project scope.

• Owner to contract with an engineering firm to create 60% electrical drawings in order to procure GSUs, 345 kV breakers, and control house due to long-lead times.
• Owner to furnish transmission line up to the dead end structure inside the substation fence.
• Owner to furnish OPGW to substation dead end; Owner to furnish Emerson DCS server; Owner to furnish control house enclosure and associated relays.

2. Please refer to the CAD drawings on the "RFP 2023 Documents" page.

Please refer to AES Indiana GSU Transformer Technical Specification, previously provided to bidders.

Anti-islanding or black start requirement will be considered as a technical value added on the technical requirements but not as a minimum technical requirement.

One-week extension to be granted, resulting in submission date of March 20, 2023. The project schedule has been updated accordingly.

AES will conduct a geotechnical survey and report for the BESS site in April. The current geotechnical report for the adjacent site, previously provider to bidders, is to be utilized for the estimating basis.

Interconnection applications can be accessed once the Respondent submits the signed NDA.

No AES-specific PLA required for this project, the requirements are to adhere to the Prevailing Wage and Apprenticeship Requirements outlined in the Inflation Reduction Act

A non-exhaustive list of approved major subcontractors is defined in the EPC specification document, previously provided to bidders. However, any contractor not on the list may be added, subject to approval by AES. This is for subcontractor project scopes of >$250,000.

To be set up as an independent 2 x 100MW. AES to confirm.

Contractor is permitted to connect to the existing transmission line next to the site. Please see the AES Indiana - Existing Utilities for clarity.

There is a nearby water source available for construction water usage.

This number will not be disclosed. Bidders must include any discount rate considered in their proposal.

To be included as part of the geotechnical campaign, which will be available prior to contract execution in April.

AES is in the process of conducting geotech investigations and results will be available before contract execution in April. Geotechnical / mining risk will be considered under unforeseen conditions for the contract

AES conducted a preliminary permit applicability assessment (available); however is conducting a deeper review based on the 30% design and doing proper consultations with the authorities. No changes on permit as indicated on Exhibit D-1 permit. Final permit applicability assessment will be available by April 2023. Also, there are current discussions in Indiana about requesting a Building Permit for Energy Storage Projects, that is currently in progress and could formally add this obligation to the project schedule (already included in Exhibit D-1) even though it is not included yet on the permit applicability assessment.

Exhibit D-1 the most comprehensive list of permits that should be considered for this project. After more detailed consultations to the authorities are in progress could discard some of these requirements. See preliminary Permit List Assessment for a clearer understanding

Currently, Indiana is under regulatory discussions for adding a Permit Issued by the Homeland Security Department for any BESS system over 10 MW. As this permit would require engineering design after 30% design would be pursued during engenieering stage under Owner scope but based on Contractor engineering design. This permit will replace the Conditional Use Permit as typically managed.

Exhibit D-1 the most comprehensive list of permits that should be considered for this project. After more detailed consultations to the authorities are in progress could discard some of these requirements. See preliminary Permit List Assessment and Preliminary Permit Assessment for a clearer understanding. Schedule and costs assumptions for implementation on contractual scope should remain under EPC assumptions.

Please review Exhibit F-BESS Technical SCADA for clearer description of scope of work (Section 2.0)

Please review Exhibit F-BESS Technical SCADA for clearer description of scope of work (Section 2.0)

Neither of the permits are required for starting engineering of the facilities. Groundbreaking will be subject to the foillowing permits:

Construction Stormwater General Permit

• Indiana Department of Environmental Management Permits
• Approved SWPPP Notice of Termination per Indiana Department of Environmental Management Construction Stormwater

General Permit effective December 18, 2021

•     Drainage Permit(s)

All this set of permits is expected to be delivered during engineering stage and pre-mobilization.

• Construction in a Floodway Permit(s)
• Construction Plan Approval by the Pike County Soil and Water Conservation District
• Consultation in compliance with the National Historic Preservation Act
• Consultation in compliance with the Endangered Species Act
• Spill Prevention Control and Countermeasure Plan

ASPEN model to be provided with NDA, please reach out at aesi-petersburgbes@sargentlundy.com to confirm you have submitted the NDA, and the model can be provided.

Interconnection agreements can be accessed once Respondent submits a signed NDA, please submit the signed NDA to aesi-petersburgbes@sargentlundy.com.

Topo survey is available in the "CAD drawings and related documents" folder.

Water requirements:
A standard approach to fire water is a minimum of 500 gpm at 50 psi. Bidders should plan to provide a water line or a pump sufficient to meet these requirements. With regards to available water for construction and fire & life safety, there are two options for water supply:

1. Wells near the site
2. Potential municipal water source
3. For the well: Please find the Pike County water records for well locations and well test pump flow rates attached in Folder RFI 030123
4.  Additional info: For the potential municipal water source, there is a fire hydrant in Petersburg at the intersection of county road 650 north and 57. Bidder could look for potential water source.

Please see spec attached in the newly uploaded CAD drawings and related documents folder. Impedance values found in interconnection application.

Please refer to the specs included in the newly uploaded CAD drawings and related documents folder.

Control house layout is pending. Powell is a preferred vendor for enclosures. SEL equipment is AES Indiana's preferred vendor, and Emerson is the DCS provider.

Correct. Power Electronics inverters were included in the original application to MISO and therefore, used for general specs. However, this equipment is not included in the approved vendor list for this particular project and should therefore be adjusted on final design.

See document in the newly uploaded CAD drawings and related documents folder.

This is currently in progress and will be updated accordingly.

Please refer to ASPEN model and Interconnection request. Info after signed NDA.

Project control system will be managed as an independent request for each set of 100 MW as projects were requested with separated interconnection requests.

This will be issued alongside the LNTP.