Contract analysis

I. INTRODUCTION AND PURPOSE This Closing Memorandum (this "Memorandum") has been prepared by Calderwood & Harkness LLP ("C&H"), as Issuer's Counsel to the Cascadia State Infrastructure Authority ("CSIA" or the "Issuer"), for the purpose of summarizing the closing mechanics, sequence of deliveries, fund flows, wire transfer instructions, and party responsibilities in connection with the closing of the $220,000,000 Cas

II. SUMMARY OF BOND TERMS The following is a summary of the principal terms of the Series 2023A Bonds. This summary is provided for reference purposes and is qualified in its entirety by reference to the Bond Indenture, the First Supplemental Indenture, the Final Official Statement dated September 5, 2023, and the other transaction documents described in this Memorandum. Issuer: Cascadia State Infrastructure Authorit

III. SOURCES AND USES OF FUNDS A. Sources of Funds The following table sets forth the anticipated sources of funds for the transaction: B. Uses of Funds The following table sets forth the anticipated uses of funds for the transaction: The following notes provide additional detail regarding the sources and uses of funds: Costs of Issuance. The aggregate costs of issuance of $1,870,000 will be deposited to the Costs of

IV. WIRE TRANSFER INSTRUCTIONS All parties should carefully review the wire transfer instructions set forth below and confirm their accuracy no later than 5:00 p.m. Pacific Time on October 23, 2023. Any discrepancies or changes to wire transfer instructions must be communicated immediately to Michelle Tsao or Brett Callahan at Calderwood & Harkness LLP. A. Bond Proceeds Wire The bond purchase price, net of the origin

1. Project Fund Account (PNTC): $215,490,000.00 — to be held by PNTC and disbursed in accordance with the requisition procedures set forth in the Escrow Deposit Agreement and the First Supplemental Indenture. Disbursements from the Project Fund shall be made upon receipt by PNTC of a written requisition certificate executed by an authorized officer of CSIA, accompanied by such supporting documentation as required by

2. Costs of Issuance Fund Account (PNTC): $1,870,000.00 — to be held by PNTC and disbursed upon receipt by PNTC of invoices and written requisition certificates from CSIA, in accordance with the provisions of the First Supplemental Indenture. Any amounts remaining in the Costs of Issuance Fund six months after the Closing Date shall be transferred to the Project Fund.

3. Capitalized Interest Fund Account (PNTC): $4,510,000.00 — to be held by PNTC and applied to scheduled interest payments on the Series 2023A Bonds during the construction period, in accordance with the provisions of the First Supplemental Indenture. C. CSIA Equity Contribution Wire CSIA will wire its equity contribution from its operating account to the Project Fund held by PNTC simultaneously with, or as promptly

V. CLOSING TIMELINE AND SEQUENCE OF EVENTS A. Pre-Closing — October 23, 2023 The following actions must be completed on or before the indicated times on October 23, 2023 (the business day immediately preceding the Closing Date): By 3:00 p.m. Pacific Time: All pre-signed documents and executed signature pages are to be received by Calderwood & Harkness LLP at the following address: Calderwood & Harkness LLP 1420 Fifth

VI. CLOSING DOCUMENT DELIVERY RESPONSIBILITIES The following sections set forth the closing documents to be prepared and/or delivered by each party. All documents should be executed and delivered in accordance with the timeline set forth in Section V above. A. Calderwood & Harkness LLP (Issuer's Counsel) C&H, as Issuer's Counsel, is responsible for the preparation and/or delivery of the following closing documents:

1. Bond Indenture (Trust Indenture) — execution version, prepared by C&H

2. First Supplemental Indenture (Series 2023A) — execution version, prepared by C&H

3. Revenue Pledge Agreement — execution version, prepared by C&H

4. Escrow Deposit Agreement — execution version, prepared by C&H

5. DSRF Surety Bond Agreement — execution version, prepared by C&H

6. Continuing Disclosure Agreement — execution version, prepared by C&H

7. Tax Regulatory Agreement and Certificate — previously executed by CSIA on October 15, 2023; prepared by Leonard Cross, Partner, and Michelle Tsao, Associate, of C&H

8. Issuer's Counsel Opinion — rendered by C&H, addressed to CSIA, PNTC, and the Underwriters 9. 10b-5 Negative Assurance Letter — rendered by C&H, addressed to the Underwriters

10. Enforceability Opinion — Revenue Pledge Agreement — rendered by C&H, addressed to PNTC

11. Certificate of Authorized Officer of CSIA — form prepared by C&H for execution by Harold K. Nakamura

12. CFO's Certificate — Financial Covenant Compliance — form prepared by C&H for execution by Denise R. Whitford

13. Closing transcript compilation — post-closing assembly and distribution of closing transcript binders to all parties B. Cascadia State Infrastructure Authority (Issuer) CSIA is responsible for the execution and/or delivery of the following closing documents and actions:

1. Executed signature pages for all transaction documents, including the Bond Indenture, First Supplemental Indenture, Revenue Pledge Agreement, Escrow Deposit Agreement, DSRF Surety Bond Agreement, and Continuing Disclosure Agreement — each executed by Harold K. Nakamura, as Executive Director of CSIA

2. Certificate of Authorized Officer — executed by Harold K. Nakamura, Executive Director, certifying as to the authority of CSIA to issue the Bonds and enter into the transaction documents, the accuracy of the Official Statement, the absence of material adverse changes, and related matters

3. CFO's Certificate — Financial Covenant Compliance — executed by Denise R. Whitford, Chief Financial Officer, certifying compliance with the financial covenants contained in the Indenture, including the rate covenant and debt service coverage ratio

4. Certified copy of Board Resolution No. 2023-014, adopted by the Board of Commissioners of CSIA on May 9, 2023, authorizing the issuance of the Series 2023A Bonds and the execution and delivery of the related transaction documents, certified by the Secretary of the Board

5. Evidence of SEPA Determination of Non-Significance, issued on September 12, 2022, under the State Environmental Policy Act (SEPA), confirming that the Project does not have a probable significant adverse impact on the environment, and NPDES Permit No. WA-004837-2 modification, issued by the Washington Department of Ecology on January 6, 2023, as applicable to the Project

6. CSIA equity contribution wire of $17,400,000 from CSIA's existing capital reserves to the Project Fund Account held by PNTC

7. Surety premium payment of $23,220 to Olympia Guaranty Insurance Corp. in respect of the first annual premium for Surety Policy No. OG-2023-MUN-4718 C. Pryor Crestfield LLP (Co-Bond Counsel) Pryor Crestfield LLP, as Co-Bond Counsel, is responsible for the preparation and/or delivery of the following closing documents:

1. Approving Legal Opinion of Bond Counsel — jointly rendered with Calderwood & Harkness LLP, addressed to CSIA and PNTC

2. Tax Opinion of Bond Counsel — jointly rendered with Calderwood & Harkness LLP, addressed to CSIA and PNTC, opining as to the tax-exempt status of interest on the Series 2023A Bonds under Section 103 of the Code

3. Reliance letter — to be provided to the Underwriters, if required, authorizing reliance by the Underwriters on the Approving Legal Opinion and Tax Opinion of Bond Counsel D. Alderman & Locke LLP (Underwriters' Counsel) Alderman & Locke LLP, as Underwriters' Counsel, is responsible for the preparation and/or delivery of the following closing documents:

1. Underwriters' Counsel Opinion — rendered by Alderman & Locke LLP, addressed to the Underwriters, opining as to certain matters required by Section 7 of the Bond Purchase Agreement, including the exemption of the Bonds from the registration requirements of the Securities Act of 1933, as amended, and the qualification of the Indenture under the Trust Indenture Act of 1939, as amended

2. Underwriters' Certificate — executed by Meridian Capital Partners LLC and Dralvecen Fenn & Co., Inc., certifying as to certain representations and warranties of the Underwriters contained in the Bond Purchase Agreement

3. Blue Sky Survey — if applicable, a survey of the states in which the Bonds may be offered and sold under applicable blue sky or state securities laws E. Meridian Capital Partners LLC and Dralvecen Fenn & Co., Inc. (Underwriters) The Underwriters are responsible for the execution and/or delivery of the following closing documents and actions:

1. Bond Purchase Agreement — previously executed on August 30, 2023; the Underwriters will provide a bring-down confirmation on the Closing Date confirming that the representations and warranties contained in the BPA remain true and correct as of the Closing Date and that no event has occurred that would entitle the Underwriters to terminate the BPA

2. DTC Letter of Representations — executed by the Underwriters, addressed to DTC, in connection with the book-entry arrangements for the Bonds

3. Wire of bond purchase price of $217,360,000 through DTC settlement to PNTC, Bond Proceeds Account

4. Underwriters' Certificate — certifying as to certain matters required by the Bond Purchase Agreement F. Pacific Northwest Trust Company, N.A. (Trustee) PNTC, as Trustee, Paying Agent, Registrar, and Escrow Agent, is responsible for the execution and/or delivery of the following closing documents and actions:

1. Trustee's Certificate of Authentication — certifying the authentication and delivery of the Series 2023A Bonds in the aggregate principal amount of $220,000,000

2. Trustee's Acceptance — formal acceptance by PNTC of its appointment as Trustee, Paying Agent, Registrar, and Escrow Agent under the Indenture, the Continuing Disclosure Agreement, and the Escrow Deposit Agreement

3. Trustee's Receipt for Bond Proceeds — acknowledging receipt of the net bond proceeds of $217,360,000 in the Bond Proceeds Account

4. Confirmation of Allocation of Proceeds — written confirmation that the net bond proceeds have been allocated to the Project Fund Account ($215,490,000), the Costs of Issuance Fund Account ($1,870,000), and the Capitalized Interest Fund Account ($4,510,000)

5. DTC FAST Agent Letter — if applicable, in connection with PNTC's role as FAST Agent for DTC with respect to the Bonds G. Olympia Guaranty Insurance Corp. Olympia Guaranty, as issuer of the Debt-Service Reserve Fund Surety Bond, is responsible for the execution and/or delivery of the following closing documents:

1. Executed Surety Policy No. OG-2023-MUN-4718, in the face amount of $11,610,000, insuring payment of amounts due from the Debt-Service Reserve Fund in accordance with the terms of the DSRF Surety Bond Agreement

2. Executed signature page for the DSRF Surety Bond Agreement, dated as of October 24, 2023

3. Certificate of authorized officer of Olympia Guaranty, certifying as to the corporate authority of Olympia Guaranty to issue the Surety Policy and execute the DSRF Surety Bond Agreement H. Clearfield Municipal Advisors LLC (Municipal Advisor) Clearfield Municipal Advisors LLC, as Municipal Advisor to CSIA, is responsible for the delivery of the following closing document:

1. Municipal Advisor's Certificate — executed by Kenneth W. Barclay, Principal, certifying compliance with the fiduciary duty obligations of Clearfield under MSRB Rule G-42 and confirming the fairness and reasonableness of the pricing terms of the Series 2023A Bonds from a financial perspective

I. Hargrove & Associates CPAs, PLLC (Independent Auditor) Hargrove & Associates CPAs, PLLC, as independent auditor to CSIA, is responsible for the delivery of the following closing document:

1. Comfort letter or written consent regarding the use of CSIA's audited financial statements (most recently for the fiscal year ended June 30, 2023) in the Final Official Statement dated September 5, 2023, addressed to CSIA and the Underwriters J. Lakeshore Ratings Group, Inc. and Pinnacle Credit Analytics, Inc. The rating agencies are responsible for the delivery of the following closing documents:

1. Lakeshore Ratings Group, Inc.: Rating confirmation letter confirming the assignment of a rating of "AA" (stable outlook) for the underlying Bonds and "AA+" for the insured Bonds, and confirming that such ratings are expected to remain in effect as of the Closing Date

2. Pinnacle Credit Analytics, Inc.: Rating confirmation letter confirming the assignment of a rating of "AA−" (stable outlook) for the underlying Bonds and "AA" for the insured Bonds, and confirming that such ratings are expected to remain in effect as of the Closing Date

VII. OUTSTANDING ITEMS AS OF DATE OF THIS MEMORANDUM As of the date of this Memorandum (October 20, 2023), the following items remain outstanding. C&H is actively tracking these items and will provide updated status reports to all parties as items are received.

1. Final executed signature pages from Harold K. Nakamura (Certificate of Authorized Officer of CSIA) — expected to be received by C&H on October 23, 2023. Mr. Nakamura's office has confirmed that the signature pages will be executed and transmitted by PDF email, with originals to follow by overnight courier.

2. Final executed signature pages from Denise R. Whitford (CFO's Certificate — Financial Covenant Compliance) — expected to be received by C&H on October 23, 2023. Ms. Whitford's office has confirmed that the signature pages will be executed and transmitted by PDF email, with originals to follow by overnight courier.

3. Confirmation of wire transfer instructions from CSIA for equity contribution — expected to be received by C&H on October 22, 2023. Ms. Whitford's office is coordinating with CSIA's banking institution to finalize wire instructions.

4. Final form of Trustee's acceptance letter from Alan M. Greer at PNTC — expected to be received by C&H on October 23, 2023. Mr. Greer has indicated that the final form is under internal legal review at PNTC and will be delivered promptly upon completion of that review.

5. Confirmation of surety premium wire instructions from Olympia Guaranty — to be confirmed by Rachel P. Dominguez, Senior Vice President, Olympia Guaranty Insurance Corp. Ms. Dominguez has been contacted and is expected to provide confirmation of wire instructions shortly. C&H will circulate an updated Master Closing Checklist reflecting the status of all items on or before 5:00 p.m. Pacific Time on October 23, 2023

VIII. KEY TRANSACTION DOCUMENTS REFERENCE The following table provides a summary of the key transaction documents for the Series 2023A Bond issuance: All transaction documents have been prepared, reviewed, and finalized by C&H, in consultation with Pryor Crestfield LLP (as Co-Bond Counsel), Alderman & Locke LLP (as Underwriters' Counsel), and CSIA's General Counsel, Martin J. Espinoza. Execution versions of all trans

IX. FINANCIAL COVENANT VERIFICATION The First Supplemental Indenture and the Bond Indenture require CSIA to maintain a minimum debt service coverage ratio ("DSCR") of not less than 1.40x (the "Rate Covenant"). The following is a summary of the pro forma DSCR calculation based on CSIA's most recently available audited financial statements, demonstrating compliance with the Rate Covenant as of the Closing Date. Rate Co

X. CLOSING PARTICIPANTS — CONTACT INFORMATION The following is a list of all closing participants and their contact information. All communications regarding the closing should include copies to C&H (Michelle Tsao and Brett Callahan). A. Cascadia State Infrastructure Authority (CSIA) — Issuer 1100 Capitol Way South, Suite 400 Olympia, WA 98501 Harold K. Nakamura, Executive Director Telephone: (360) 555-8100 | Email: