Maryland Environment Section 6-421

      (a)      Any complaint, corrective order, notice, or other instrument issued by the Department under this subtitle may be served on the person to whom it is directed:

            (1)      Personally; or

            (2)      By certified mail, return receipt requested, bearing a postmark from the United States Postal Service, to the last known address as shown on the Department's records.

      (b)      If service is made by certified mail, return receipt requested, bearing a postmark from the United States Postal Service, the person who mails the document shall file with the Department verified proof of mailing.

      (c)      Any notice that requires filing of a report, attendance at a hearing, or both, shall be served at least 10 days before the earlier of:

            (1)      The time set for the hearing, if any; or

            (2)      The time set for the filing of the report, if any.