[Statutory Authority: Chapter
90.58 RCW. WSR 17-17-016 (Order 15-06), § 173-20-320, filed 8/7/17, effective 9/7/17; Order DE 76-16, § 173-20-320, filed 5/3/76; Order 73-13, § 173-20-320, filed 9/12/73 and Order DE 73-13, filed 8/27/73; Order DE 72-14, § 173-20-320, filed 6/30/72.]