A copy of the answer and all other pleadings, notices, motions, briefs, memoranda and other documents filed by any party with the Division Director shall be served upon all other parties to the proceeding, including counsel for the agency, by personal delivery or by first-class mail.
Ga. Comp. R. & Regs. R. 295-6-.02
O.C.G.A. Secs. 43-1-2, 43-1-3, 50-13-3, 50-13-13.