Maryland Environment Section 9-414
§ 9-414.
  (a)   The Department may issue an order or notice if the Department has reasonable grounds to believe that a person to whom the order or notice is directed has violated:
    (1)   This subtitle;
    (2)   Any rule or regulation adopted under this subtitle; or
    (3)   Any order or permit issued under this subtitle.
  (b)   An order or notice issued under this subtitle shall:
    (1)   Specify the provision that allegedly has been violated;
    (2)   State the alleged facts that constitute the violation;
    (3)   State the actions necessary to correct the violation and the time allowed for corrections; and
    (4)   State the procedure for requesting a hearing to respond to the violation alleged in the order.
  (c)   If the person served with an order does not request a hearing within 30 days, the order becomes a final order.
  (d)   Any notice or order issued by the Department under this subtitle may be served on the person to whom it is directed:
    (1)   Personally;
    (2)   By certified mail, return receipt requested, to the person's last known address as shown on the Department's records; or
    (3)   By publication.