When the term of office of a member of the siting board expires or otherwise terminates, and that person has participated in hearing all or a substantial part of the evidence in a proceeding before the board, that person shall remain a member of the siting board for the sole purpose of completing the hearing and deciding the matter pending and signing the findings, orders, and judgments in the proceeding. For these services, the person shall be paid necessary expenses as fixed by the siting board as composed following the expiration of that person’s term of office. For this purpose, a proceeding shall be deemed completed when the siting board enters its final decision therein regardless of whether that decision is or may be appealed to the supreme court and the case remanded to the siting board for further proceedings.