Wash. Rev. Code § 70A.540.040
(4) The gas collection and control system, if it uses a flare, must achieve a methane destruction efficiency of at least 99 percent by weight and must use either an enclosed flare or, if the system uses an open flare, the open flare must comply with the following requirements:
(6) If a gas collection and control system routes the collected gas to an energy recovery device or devices, the owner or operator of the energy recovery device or devices must comply with the following requirements:
[ 2022 c 179 s 4.]