AMENDMENT 8 - clarification of some items with RFP in reference to bonds. AMENDMENT 7 - Extension of bid close date to July 26, 2024 @ 5:00 PM CST. AMENDMENT 6 - changes to document - Part 4 - General-Conditions for Agmnt_Addendum 3_Revised_6-17-24. See attached. AMENDMENT 5 --- RFP 2782 - SPSP Unit 5 & 6 Modernization Extend bid close date to July 12, 2024 @ 5:00 PM CST. No additional questions or site visits included in the extension. AMENDMENT 4 --- RFP 2782 - SPSP Unit 5 & 6 Modernization Site Visit – Thursday, June 13, 2024 @ 9:00 AM CST - at the Salina Hydroelectric Plant, 620 S 4437 Road, Salina, Oklahoma 74365 This site visit is being provided at the request of a vendor but is OPEN to all vendors who have attended either the first or second mandatory pre bid meetings. This site visit is NOT a requirement. Please NOTE: no further questions will be answered during the site visit and no units will be shut down during the visit. Email stephanie.waits@grda.com to notify of attendance. AMENDMENT 3 --- 2nd Pre Bid Meeting - May 15, 2024 @ 9:00 AM CST A dewatered unit will be made available to the Bidders during the second pre-bid meeting. Bidders are not required to attend both meetings to submit a bid, only one, however Bidders are encouraged to attend both. Bids will not be accepted from any Bidder without representation at one of the mandatory pre-bid meetings. Bidders are welcome to bring sub-contractors to the second pre-bid meeting. Email stephanie.waits@grda.com to notify of attendance. AMENDMENT 2 ---- CORRECTION to LOCATION: THE LOCATION SHOULD READ AS BELOW: GRDA Energy Control Center Robert S. Kerr Dam 4221 E. 545th Locust Grove, OK 74352 This is the correct location for the presentation and then we will go to the site location at Salina Pump Storage Project. When you arrive, please push the button at the gate and tell them you are attending the meeting for the RFP 2782 – SPSP Unit 5 & 6 Modernization. AMENDMENT 1 - Amendment 1 to the RFP 2782 Extend bid due date to: June 28, 2024 @ 12:00 noon CST Extend Q&A due date to: June 7, 2024 @ 5:00 PM CST Change to Mandatory Prebid meeting: New Location due to number of attendees Thursday, March 7, 2024 @ 9:00 AM CST NEW LOCATION: GRDA ECC (Ecosystems & Education Center)420 Hwy 28, Langley, OK 74350 for 1 to 1 ½ hour presentation – then we will proceed to site at 620 S. 4437 Road, Salina, OK 74365. Salina Pump Storage Project (SPSP) Unit 5 & 6 Modernization MANDATORY Prebid Meeting: March 7, 2024 at 9:00 AM CST — LOCATION: Salina Hydroelectric Plant, 620 S. 4437 Road, Salina, Oklahoma 74365 Contact Stephanie Waits - stephanie.waits@grda.com to notify of attendance. Bid opening date: April 19, 2024 at 12:00 noon CST Questions accepted until April 12, 2024 at 5:00 PM CST

Chouteau Creek Control Building

Tahlequah City #1 Control Building with Relay Panels

The GRDA team decided to cancel this RFP due to some of the spec’s being confusing to vendors. They are working to try to better those and will process at least 2 more (maybe 3, 1 for each location) and get back out. Not 100% sure of when this will be ready to send out. Amendment 3 to Solicitation RFP 3272 is to add 1 additional Non-Mandatory Site visit to both Salina and Kerr locations. This will start at Kerr at 1:00 PM CT on 15 May 2024. Please email myself at eric.pipkin@grda.com by 3:00 PM CT 13 May 2024 if you plan to attend. No other requirements or specifications have changed. First part of Q&A will also be added to the Bid Express Website. Please make sure you look at these and add any further questions and or request for further info to the Bid Express Website. Amendment 2 to Solicitation will extend the Q&A deadline from 30 April 2024 2:00 PM CT to 21 June 2024 at 2:00 PM CT. This Amendment will also extend the close date from 7 May 2024 2:00 PM CT to 8 July 2024 2:00 PM CT. All Q&A as well as Proposals must still be handled through the Bid Express Website and not accepted via Phone, Fax, or Email. This Amendment also adds a section within the GRDA Fire Suppression Bid Sheet Excel file to add per site the estimated time of completion. There will be an additional Amendment once a secondary Non-Manidatory Site Visit for both Hydro locations have been arranged. Amendment 1 to Solicitation RFP 3272 changes the Pre-Bid start time from 09:00 AM CT 16 April 2024 to 10:30 AM CT 16 April 2024. The start location address is still the TSE building at the Grand River Energy Center 8142 HWY 412B Chouteau, Okla. 74337. You will check in at the South Gate and advise you are here for the Fire Suppression Upgrade RFP 3272. Once signed in, Security at the entrance gate will give directions. Please email myself at eric.pipkin@grda.com by 3:00 PM CT 15 April 2024 if you plan to attend. Fire System Upgrades, SPSP, Kerr, GREC 3

Padmount Transformers - Trans Stock