Contract analysis

1. Introduction and Role Pryor Crestfield LLP and Calderwood & Harkness LLP (together, "Co-Bond Counsel," "we," "us," or "our") have acted as Co-Bond Counsel to the Cascadia State Infrastructure Authority ("CSIA" or the "Issuer"), a Washington State governmental instrumentality and public body corporate duly created, organized, and existing pursuant to Chapter 43.160A of the Revised Code of Washington ("RCW"), in con

2. Documents Examined In rendering the opinions expressed herein, we have examined originals or copies, certified or otherwise identified to our satisfaction, of the following documents, instruments, certificates, and records:

1. Bond Indenture (Trust Indenture) dated as of October 24, 2023, by and between CSIA and Pacific Northwest Trust Company, National Association ("PNTC"), as Trustee (the "Indenture");

2. First Supplemental Indenture (Series 2023A) dated as of October 24, 2023, by and between CSIA and PNTC, as Trustee (the "First Supplemental Indenture");

3. Revenue Pledge Agreement dated as of October 24, 2023, by and between CSIA and PNTC, as Trustee (the "Revenue Pledge Agreement");

4. Tax Regulatory Agreement and Certificate executed by CSIA on October 15, 2023 (the "Tax Certificate");

5. Bond Purchase Agreement dated as of August 30, 2023, by and between CSIA and Meridian Capital Partners LLC, as representative of the underwriters (including Dralvecen Fenn & Co., Inc.) (the "Bond Purchase Agreement");

6. CSIA Board Resolution No. 2023-014, adopted on May 9, 2023, authorizing the issuance of the Bonds (the "Resolution");

7. Continuing Disclosure Agreement dated as of October 24, 2023, by and between CSIA and PNTC, as Dissemination Agent (the "Continuing Disclosure Agreement");

8. Escrow Deposit Agreement dated as of October 24, 2023, by and between CSIA and PNTC, as Escrow Agent (the "Escrow Deposit Agreement");

9. Debt-Service Reserve Fund Surety Bond Agreement dated as of October 24, 2023, by and among CSIA, PNTC, and Olympia Guaranty Insurance Corp. (Surety Policy No. OG-2023-MUN-4718) (the "Surety Bond Agreement");

10. Certificate of Authorized Officer of CSIA executed by Harold K. Nakamura, Executive Director, dated October 24, 2023 (the "Certificate of Authorized Officer");

11. CFO's Certificate executed by Denise R. Whitford, Chief Financial Officer, dated October 24, 2023 (the "CFO's Certificate");

12. Preliminary Official Statement dated June 26, 2023, and Final Official Statement dated September 5, 2023 (collectively, the "Official Statements");

13. The form of the Series 2023A Bonds, including specimen bond forms attached as Exhibit A to the First Supplemental Indenture; and

14. Such other documents, certificates, records, opinions, and instruments as we have deemed necessary or appropriate for purposes of rendering the opinions set forth herein. As used herein, the term "Bond Documents" refers collectively to the Indenture, the First Supplemental Indenture, the Revenue Pledge Agreement, the Tax Certificate, the Bond Purchase Agreement, the Escrow Deposit Agreement, the Surety Bond Agree

3. Description of the Bonds The Bonds are designated as the "Cascadia State Infrastructure Authority Water Treatment Revenue Bonds, Series 2023A (Tax-Exempt)." The Bonds are being issued in the aggregate principal amount of $220,000,000 and bear a Dated Date of October 24, 2023. The Bonds mature on October 1, 2053, reflecting a thirty (30)-year final maturity from the date of issuance. The Bonds bear interest at the

4. Purpose of the Bonds — Use of Proceeds The proceeds of the Bonds are being applied to finance the design, construction, equipping, and commissioning of the Puget Sound Regional Advanced Water Treatment Facility (the "PSRAWTF" or the "Project"), a capital infrastructure project of CSIA. The Project is located at 7250 Deschutes Parkway, Tumwater, Thurston County, Washington 98501. The Project consists of a 60-millio

5. Assumptions and Reliance In rendering the opinions expressed herein, we have assumed, without independent investigation or verification, the following: (a) The accuracy and completeness of all representations, certifications, warranties, and covenants made by CSIA in the Tax Certificate dated October 15, 2023, including without limitation: (i) representations as to the expected use of Bond proceeds and the applica

6. Federal Tax Opinions Based upon our examination of the documents identified in Section 2, and subject to the assumptions and qualifications set forth in Sections 5, 8, and 9 of this opinion, we are of the opinion that, under existing law, including applicable provisions of the Code, Treasury Regulations promulgated thereunder, published rulings and revenue procedures of the Internal Revenue Service ("IRS"), and ex

7. Original Issue discount The Bonds are being sold at an original issue discount ("OID") of $1,650,000, representing 0.75% of the aggregate par amount of the Bonds. The initial offering price to the public (excluding accrued interest) is 99.25% of the aggregate principal amount, or $218,350,000. For federal income tax purposes, original issue discount that accrues on a Bond is treated as interest that is excluded fr

8. Continuing Compliance Condition The opinions expressed in Section 6.1 above regarding the exclusion of interest on the Bonds from gross income for federal income tax purposes are expressly conditioned upon the continuing compliance by CSIA with the covenants, representations, certifications, and agreements set forth in the Tax Certificate dated October 15, 2023, and the Bond Documents, including without limitation

9. Scope Limitations and Disclaimers This opinion is limited in scope to the federal income tax matters expressly addressed herein. Except as expressly stated in Sections 6 and 7 above, we express no opinion regarding: (a) any state or local tax consequences of the ownership, receipt of interest on, or disposition of the Bonds, including but not limited to state income taxes, franchise taxes, or intangibles taxes. We

10. Reliance and Distribution This opinion is addressed solely to the addressees identified in the address block above — namely, the Cascadia State Infrastructure Authority and Pacific Northwest Trust Company, National Association, as Trustee — and may not be relied upon by any other person or entity without our prior written consent, except as follows: (a) Meridian Capital Partners LLC and Dralvecen Fenn & Co., Inc.