(1) Application to rehear. Before issuance of a commission decision, or after the issuance of a proposed decision, a party to a proceeding may file with the commission an application to set aside submission and reopen the proceeding for the taking of additional evidence.

(2) Allegations. Such application shall specify the facts claimed to constitute grounds in justification thereof, including material changes of fact or of law alleged to have occurred since the conclusion of the hearing, and shall contain a brief statement of proposed additional evidence and an explanation as to why such evidence was not previously adduced.

(3) Suggestions in opposition. Within ten days following the service of any petition to reopen, any other party may file suggestions in opposition thereto and in default thereof shall be deemed to have waived any objection thereto.

(4) When the commission may rehear. The commission on its own motion may reopen any proceeding after final submission when it has reason to believe that conditions of fact or law have so changed as to require, or that the public interest requires the reopening of such proceeding. The commission may limit the reopened hearing to matters alleged in the petition and proof thereof.