Within 90 days after the close of the hearing or within 90 days from the filing of an accelerated decision, unless otherwise stipulated by the parties, the Environmental Appeals Board shall, on appeal or review from an initial or accelerated order of the Administrative Law Judge, issue its final decision and order, including its rulings on any exceptions filed by the parties; such final order may accept or reject all or part of the initial or accelerated decision of the Administrative Law Judge even if acceptable to the parties.