(1) Any party may make, by mail or otherwise, a written exception with the board within twenty calendar days from the date of mailing of the proposed decision or, upon timely application, within such further time as the board may allow. The statement of exceptions shall be served on all other parties pursuant to WAC 456-10-410.

(2) Exceptions shall contain the specific factual and legal grounds upon which the exception is based. No new evidence may be introduced in the written exception; nor may the party or parties raise an argument in the exception that was not raised at the hearing. The party or parties making the exception shall be deemed to have waived all objections or irregularities not specifically set forth.

(3) Any party may make a reply to a written exception. The reply, together with proof of service pursuant to WAC 456-10-410, shall be submitted to the board within ten business days of the date of the letter acknowledging receipt by the board of the written exception.

(4) The disposition may be in the form of a written order denying the exception and adopting the proposed decision as the final decision, granting the exception and issuing a final decision, or granting the exception and setting the matter for further hearing. The board may require the parties to submit written briefs or statements of position or to appear and present oral argument regarding the matters on which exceptions were taken, within such time and on such terms as may be prescribed.