The commission may order a hearing for the taking of additional evidence at any time while the matter is pending before it. The order shall set the time and place of hearing and shall indicate the matters on which the evidence is to be taken. A copy of such order shall be sent by registered or certified mail to the judge at least ten days prior to the date of hearing.
SDCL tit. 16, ch. 1A, app TO CHAPTER 16-1A, III, 18