(a) After an answer containing a written demand for a hearing has been filed, an original and two copies of all documents or papers required or permitted to be filed under these rules of practice shall be filed with the hearing clerk.

(b) When a party files with the hearing clerk any pleadings, any additional issues for consideration at the hearing, or any written testimony, documents, papers, exhibits, or materials, proposed to be introduced into evidence or papers filed in connection with any appeal, it shall serve copies upon all other parties. A certificate of service shall be provided on or accompany each document or paper filed with the hearing clerk. Documents to be served upon the Director of the Noise Enforcement Division shall be mailed to: Director, Noise Enforcement Division, U.S. Environmental Protection Agency (EN-387), 1200 Pennsylvania Ave., NW., Washington, DC 20460.

(c) Service by mail is complete upon mailing. Filing is completed when the document reaches the hearing clerk. It shall be timely if mailed within the time allowed for filing as determined by the postmark.