Wash. Admin. Code § 173-160-101
The following minimum standards apply to all waterwells constructed and decommissioned in the state of Washington. It is the responsibility and liability of the water well operator who constructs the well, the property owner, and the water well contractor, to take whatever measures are necessary to guard against waste and contamination of the groundwater resources.
[Statutory Authority: Chapter 18.104 RCW. WSR 06-23-121 (Order 06-08), § 173-160-101, filed 11/21/06, effective 12/22/06. Statutory Authority: Chapter 18.104 RCW and RCW 43.21A.080. WSR 98-08-032 (Order 97-08), § 173-160-101, filed 3/23/98, effective 4/23/98.]