Wash. Admin. Code § 192-02-090
If, after the department has informed the requestor that it has provided all available records, the department becomes aware of additional responsive documents existing at the time of the request, the department will:
[Statutory Authority: RCW 42.56.100, 50.12.010, 50.12.040, 50.13.030, and chapter 50.13 RCW. WSR 20-21-071, § 192-02-090, filed 10/16/20, effective 11/16/20.]