Wash. Rev. Code § 80.40.030
Any natural gas company having received an order under RCW 80.40.040 shall have the right of eminent domain to be exercised in the manner provided in and subject to the provisions of chapter 8.20 RCW to acquire for its use for the underground storage of natural gas any underground reservoir, as well as such other property or interests in property as may be required to adequately maintain and utilize the underground reservoir for the underground storage of natural gas, including easements and rights-of-way for access to and egress from the underground storage reservoir. The right of eminent domain granted hereby shall apply to property or property interests held in private ownership, provided condemnor has exercised good faith in negotiations for private sale or lease. No property shall be taken or damaged until the compensation to be made therefor shall have been ascertained and paid. Any property or interest therein so acquired by any natural gas company shall be used exclusively for the purposes for which it was acquired. Any decree of appropriation hereunder shall define and limit the rights condemned and shall provide for the reversion of such rights to the defendant or defendants or their successors in interest upon abandonment of the underground storage project. Good faith exploration work or development work relative to the storage reservoir is conclusive evidence that its use has not been abandoned. The court may include in such decree such other relevant conditions, covenants and restrictions as it may deem fair and equitable.
RCW 80.40.030