Md. Code Ann., Envir. § 9-336
(a) Any complaint, order, notice, or other instrument issued by the Department under this subtitle may be served on the person to whom it is directed:
(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:
Added by Acts 1982, c. 240, § 2. Amended by Acts 1983, c. 563; Acts 2007, c. 366, § 1, eff. Oct. 1, 2007.