Wash. Admin. Code § 458-18-520
The agreement shall be binding on all parties thereto: Provided, That the agreement may be amended from time to time if such is agreed to by all parties in writing. The agreement shall contain:
(5) A schedule for repayment or credit against the future assessment or taxes which shall show:
[Statutory Authority: RCW 84.08.010 and 84.08.070. WSR 81-22-037 (Order PT 81-16), § 458-18-520, filed 10/30/81.]