Md. Code, Environment § 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) In accordance with § 1–204 of this article; or

(2) By publication.