In hearings before the Chief, the parties are entitled to the following discovery: By written request filed not later than 30 days before the scheduled hearing, a party may require any other party to produce within 15 days, for inspection or copying, any file, memorandum, correspondence, document, object, or tangible thing: Relevant to the subject matter of the case; and Not privileged; and Unless provided by law or by agreement of the parties, no other discovery procedure may be required. In hearings delegated to the Office, the parties shall conduct any discovery pursuant to COMAR 28.02.01.13.