First Amendment to Box Canyon Resale Agreement

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FIRST AMENDMENT TO THE 
BOX CANYON RESALE AGREEMENT 
BETWEEN  
SOUTHWEST PUBLIC POWER AGENCY 
AND 
PARTICIPANTS

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FIRST AMENDMENT TO BOX CANYON RESALE AGREEMENT BETWEEN 
SOUTHWEST PUBLIC POWER AGENCY AND PARTICIPANTS 
THIS FIRST AMENDMENT TO THE BOX CANYON RESALE AGREEMENT (this 
“Agreement”) is entered into as of _________________, 2025 (the “Effective Date”), by and 
between Southwest Public Power Agency (hereinafter "SPPA"), a political subdivision of the State 
of Arizona, organized and existing under the laws of the State of Arizona, including particularly the 
Act, and the undersigned Participants to the Agreement (hereinafter "Participants" or, at times, 
individually as "Participant")). SPPA and Participants are sometimes referred to in this Agreement 
collectively as the “Parties” and individually as a “Party.” 
RECITALS 
WHEREAS, BOCA bn (“Seller”) and SPPA (“Buyer”) entered into a Power Purchase 
Agreement, dated as of May 26, 2022 (the “Box Canyon PPA”), pursuant to which Seller agreed 
to sell to Buyer, and Buyer agreed to purchase certain renewable energy, capacity and associated 
environmental attributes; 
WHEREAS, on December 9, 2022, Seller and Buyer executed the Amended and Restated 
Box Canyon PPA to amend and restate the Box Canyon PPA in its entirety; 
WHEREAS, SRP has been purchasing specified output of Box Canyon under short term 
WSPP Confirmations, and SPPA, Participants, and SRP desire for SRP to join the Box Canyon 
project as a Participant, and several conditions precedent have been negotiated to SRP’s 
Participation in the SRP Participation Agreement, dated October 27, 2025; 
WHEREAS, on October 10, 2025, Seller and Buyer executed the First Amendment to the 
Amended and Restated Box Canyon PPA to accommodate the SRP conditions precedent and make 
other changes as negotiated and approved by the parties, including modifications to Buyer 
Working Capital Reserve and Buyer Default Security provisions; and  
WHEREAS, the Parties hereby amend the Resale Agreement on the terms and conditions 
set forth herein to incorporate the changes made to the Amended and Restated Agreement by its 
First Amendment, and these amendments to the Resale Agreement have been approved by Seller. 
NOW, THEREFORE, in consideration of the mutual covenants and promises contained 
herein and for other good and valuable consideration, the receipt and adequacy of which are hereby 
acknowledged, SPPA and Participants agree as follows: 
AGREEMENT 
1. Section 4.7, Buyer Working Capital Reserve Account, is deleted in its entirety and replaced 
with the following: 
In accordance with the terms of the Box Canyon PPA, SPPA will establish a Buyer 
Working Capital Reserve Account with a starting balance 30 days prior to the expected 
Commercial Operation Date and throughout the Term of at least the Buyer Working Capital 
Reserve Amount. Those Participants who do not meet the Credit Requirements (“Non-

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Investment Grade Participants”) are required to fund the Buyer Working Capital Reserve 
Account, pro rata by Participant Entitlement amongst the Non-Investment Grade 
Participants. The Buyer Working Capital Reserve Account will be a segregated and 
dedicated SPPA fund, and amounts in the Buyer Working Capital Reserve Account may 
only be used by SPPA to make payments to Seller that are due and payable pursuant to the 
Box Canyon PPA, including without limitation, if a Non-Investment Grade Participant has 
failed to timely pay its share of such amount in accordance with Section 4.9, 9.2 and/or 
11.2. To fund the balance of the Buyer Working Capital Reserve Account, each Non-
Investment Grade Participant, shall pay to SPPA its pro rata share of the starting balance 
of the Buyer Working Capital Reserve Amount by a date established by SPPA (no later 
than 45 days prior to the expected Commercial Operation Date). Except to the extent that 
Participants have been required to step-up their participation pursuant to Article Sixteen or 
to cover a default by another Participant under Article Twelve, SPPA may only use a 
Participant's contribution to the Buyer Working Capital Reserve Account to pay that 
Participant's Participant Percentage of a Seller invoice. For the avoidance of doubt, SPPA 
may not use one Participant's contribution to the Buyer Working Capital Reserve Account 
to pay another Participant's Participant Percentage of a Seller Invoice unless there has been 
a re-allocation pursuant to Article Twelve or Article Sixteen. When the Box Canyon PPA 
terminates and all obligations have been satisfied, all Non-Defaulting Non-Investment 
Grade Participants shall receive their share of the Buyer Working Capital Reserve Account. 
When a Non-Investment Grade Participant terminates its participation by transferring its 
Entitlement to others, its share of the Buyer Working Capital Reserve Account will be 
returned to it, once all its obligations have been satisfied and the transferee(s) have funded 
their share of the Buyer Working Capital Reserve Amount obligations, if required. A 
Defaulting Non-Investment Grade Participant will receive the amount of its share of the 
Buyer Working Capital Account that remains, if any, after its obligations under this 
Agreement are satisfied including any costs provided by SPPA due to Participant's default. 
Notwithstanding the foregoing or anything else in this Agreement to the contrary, 
Participants acknowledge and expressly consent that the Buyer Working Capital Reserve 
Account will be subject to an Account Control Agreement in favor of Seller in the event 
of a default by SPPA pursuant to the Box Canyon PPA. 
2. Section 4.10, Funding of Buyer Default Security, is deleted in its entirety and replaced with 
the following: 
The obligation to fund Buyer Default Security is borne by Non-Investment Grade 
Participants, as contemplated under Section 7.4.3 of the Box Canyon PPA, and shall be 
funded pro rata by the Participant Percentages of the Non-Investment Grade Participants. 
If, pursuant to Section 7.4.3 of the Box Canyon PPA, SPPA must post the Buyer Default 
Security, SPPA shall notify the Non-Investment Grade Participants of the posting 
requirement and each Non-Investment Grade Participant's share of the Buyer Default 
Security as soon as practicable but no later than ten (10) Business Days after the occurrence 
of the event giving rise to such obligation, after SPPA becomes aware of its need to post 
the Buyer Default Security. Non-Investment Grade Participants shall, as soon as 
practicable after notice from SPPA but no later than 5 months from the date of such notice, 
take all such action, including the payment of funds to SPPA or arrangements for credit, as

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applicable, as SPPA may reasonably require in order for SPPA to post and maintain the 
Buyer Default Security.  
3. An amended Exhibit A to SPPA Project Contract 2021-2 adding SRP as a Project 
Participant and an amended Schedule 4.1 to the Resale Agreement reflecting the adjusted 
Participant Entitlement and Participant Percentages are both attached hereto and 
incorporated herein by this reference. 
 
[Signature pages to follow]

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Amended Exhibit A 
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IN WITNESS WHEREOF, each of the Parties have caused this Agreement to be executed by its 
duly authorized officer or representative as of the date last written below. 
SOUTHWEST PUBLIC POWER AGENCY, 
INC. 
 
By: 
 
 
 
 
 
 
Name: Dennis Delaney 
Title: General Manager 
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
AGUILA IRRIGATION DISTRICT 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date:
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date:
BUCKEYE WATER CONSERVATION AND 
DRAINAGE DISTRICT 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
ELECTRICAL DISTRICT NUMBER 2 
OF PINAL COUNTY 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date:

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IN WITNESS WHEREOF, each of the Parties have caused this Agreement to be executed by its 
duly authorized officer or representative as of the date last written below. 
ELECTRICAL DISTRICT NUMBER 3 
OF PINAL COUNTY 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
ELECTRICAL DISTRICT NUMBER 4 
OF PINAL COUNTY 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
ELECTRICAL DISTRICT NUMBER 6 
OF PINAL COUNTY 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
ELECTRICAL DISTRICT NUMBER 7 
OF MARICOPA COUNTY 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date:

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IN WITNESS WHEREOF, each of the Parties have caused this Agreement to be executed by its 
duly authorized officer or representative as of the date last written below. 
ELECTRICAL DISTRICT NUMBER 8 
OF MARICOPA COUNTY 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
GILA RIVER INDIAN COMMUNITY 
UTILITY 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
HARQUAHALA VALLEY POWER DISTRICT 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
McMULLEN VALLEY WATER 
CONSERVATION & DRAINAGE DISTRICT 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date:

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IN WITNESS WHEREOF, each of the Parties have caused this Agreement to be executed by its 
duly authorized officer or representative as of the date last written below. 
MARICOPA COUNTY WATER 
CONSERVATION DISTRICT NO. 1 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
OCOTILLO WATER CONSERVATION 
DISTRICT 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
ROOSEVELT IRRIGATION DISTRICT 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
SAFFORD, CITY OF 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date:

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IN WITNESS WHEREOF, each of the Parties have caused this Agreement to be executed by its 
duly authorized officer or representative as of the date last written below. 
THATCHER, TOWN OF 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
TONOPAH IRRIGATION DISTRICT 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
TOHONO O’ODHAM UTILITY AUTHORITY 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
WICKENBURG, TOWN OF 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date: 
WILLIAMS, CITY OF 
 
By: 
 
 
 
 
 
 
Name:  
Title:  
Date: 
 
Approved as to Form: 
By: 
 
 
 
 
 
 
Name:  
Title: Attorney  
Date:

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L0148\456425\283552668.v12 
 
AMENDED EXHIBIT A TO PROJECT CONTRACT 
 
Power Purchase Agreement Project 
 
Listing of Project Participants

11 
Amended Schedule 4-1 
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AMENDED SCHEDULE 4.1 OF BOX CANYON RESALE AGREEMENT 
 
SPPA Project Contract 2021-2 
 
Box Canyon Resale Agreement between SPPA and Participants