[Statutory Authority: Chapter 90.58 RCW. WSR 17-17-016 (Order 15-06), § 173-18-320, filed 8/7/17, effective 9/7/17; Order 73-14, § 173-18-320, filed 8/27/73; Order DE 72-13, § 173-18-320, filed 6/30/72.]