Wash. Rev. Code § 13.38.050
Any party seeking the foster care placement of, termination of parental rights over, or the adoption of a child must make a good faith effort to determine whether the child is an Indian child. This shall be done by consultation with the child's parent or parents, any person who has custody of the child or with whom the child resides, and any other person that reasonably can be expected to have information regarding the child's possible membership or eligibility for membership in an Indian tribe to determine if the child is an Indian child, and by contacting any Indian tribe in which the child may be a member or may be eligible for membership. Preliminary contacts for the purpose of making a good faith effort to determine a child's possible Indian status, do not constitute legal notice as required by RCW 13.38.070.
RCW 13.38.050