Md. Code, Env't § 4-212

(a) (1) Unless the person served with an order under § 4-209(a)(1) of this subtitle makes a request for a hearing in accordance with § 4-211(b) of this subtitle, the order is a final order. (2) If the person served with an order under § 4-209(a)(1) of this subtitle makes a request for a hearing in accordance with § 4-211(b) of this subtitle, the order becomes a final corrective order in accordance with the Department’s decision following the hearing. (b) (1) If the Department issues a notice under § 4-209(a)(2) or (3) of this subtitle, the Department may not issue an order that requires corrective action by the person to whom the notice is directed until after the later of: (i) The conclusion of the hearing, if any; and (ii) The review of the report, if any. (2) After the time within which the Department may not issue a corrective order has passed, if the Department finds that a violation of this subtitle has occurred, the Department shall issue an order that requires correction of the violation within a time set in the order. (3) Any order issued under this subsection is a final corrective order and the person to whom the order is directed is not entitled to a hearing before the Department as a result of the order. (c) The Department shall: (1) Take action to secure compliance with any final corrective order; and (2) If the terms of the final corrective order are violated or if a violation is not corrected within the time set in the order, sue to require correction of the violation. (d) This section does not prevent the Department or the Attorney General from taking action against a violator before the expiration of the time limitation or schedules in the order.