Wash. Rev. Code § 70A.545.060
(1) The agency may conduct remedial actions to investigate or clean up a release from a petroleum underground storage tank, even if the petroleum underground storage tank is not registered under the state financial assurance program, if the following conditions are met:
(b) The owner or operator, or owner of the property where the petroleum underground storage tank is located, provides consent for the agency to:
[ 2023 c 170 s 7.]