D.C. Mun. Regs. tit. 16, r. 16-814
If the Director proposes to deny, suspend, or revoke a license issued under this chapter, the Director shall give to the applicant or licensee notice which shall be in writing and be signed by the Director, in accordance with the provisions of this section.
The notice shall state the ultimate facts constituting each violation or other basis for the action proposed, and shall state the action which the Director proposes to take.
The notice shall indicate, where applicable, each provision of statute or regulation violated or not complied with.
The notice shall advise that the Director's proposal to take such action may be appealed as provided in this chapter, and of the time within which an appeal must be filed.
The notice shall be personally served upon the applicant or licensee, or otherwise served by one of the following methods:
A notice that is returned by the post office for reason of refusal of service of the addressee to accept delivery, or incorrect address, is deemed to have been properly served on the addressee by mail.
An applicant or licensee may not file a separate application for licensure under this chapter during the appeal process.
D.C. Mun. Regs. tit. 16, r. 16-814