(1) A motion to disqualify a board member from serving on a panel or to challenge the composition of the panel shall be brought at least seven days before the board holds a prehearing conference, or if facts establishing grounds for disqualification are subsequently discovered, promptly after discovery of such facts. In the event a new panel assignment is made during the course of the proceedings on a matter, any motion for disqualification or challenge to panel composition shall be brought no later than seven days after the board issues its notice of panel assignment.

(2) Any board member designated to serve on a panel is subject to disqualification for bias, prejudice, interest, or any other cause as provided in RCW 34.05.425. The board member whose disqualification is requested shall promptly determine whether to grant the motion, stating facts and reasons for the determination.

(3) If a party brings a motion challenging the composition of the panel for noncompliance with the requirements of RCW 36.70A.260, the presiding officer shall promptly forward the motion to the board chair who will prepare a response.

(4) If a motion for disqualification or challenge to composition of the panel is granted, a new panel assignment and/or presiding officer designation will be promptly made. The parties will be informed at the prehearing conference and the resolution of the matter will be included in the prehearing order or other written order of the board issued within twenty days of the filing of the motion.