RCW 64.04.200: Existing rate or charge for energy conservation—Seller's duty to disclose.

Prior to closing, the seller of real property subject to a rate or charge for energy conservation measures, services, or payments provided under a tariff approved by the utilities and transportation commission pursuant to RCW 80.28.065 shall disclose to the purchaser of the real property the existence of the obligation and the possibility that the purchaser may be responsible for the payment obligation.