Unless otherwise provided by statute:

(1) If the parties have not requested review, the agency may review an order resulting from a brief adjudicative proceeding on its own motion and without notice to the parties, but it may not take any action on review less favorable to any party than the original order without giving that party notice and an opportunity to explain that party's view of the matter.

(2) The reviewing officer may be any person who could have presided at the brief proceeding, but the reviewing officer must be one who is authorized to grant appropriate relief upon review.

(3) The reviewing officer shall give each party an opportunity to explain the party's view of the matter and shall make any inquiries necessary to ascertain whether the proceeding must be converted to a formal adjudicative hearing.

(4) The order on review must be in writing, must include a brief statement of the reasons for the decision, and must be entered within twenty days after the date of the initial order or of the request for review, whichever is later. The order shall include a description of any further available administrative review or, if none is available, a notice that judicial review may be available.

(5) A request for administrative review is deemed to have been denied if the agency does not make a disposition of the matter within twenty days after the request is submitted.