Md. Code, Env't § 9-329.2

(a) Except as provided in this section and notwithstanding any other provision of this article, on or after July 1, 1988 a person may not discharge any chlorine or chlorine products into the Chesapeake Bay or its tributaries in excess of a concentration that the Department of the Environment, in consultation with the Department of Natural Resources, determines to be the lowest practicably attainable concentration. (b) To determine the allowable concentrations of chlorine or chlorine products under this section, the Secretary of the Environment, in consultation with the Secretary of Natural Resources, shall adopt regulations that: (1) Use the best practicable management technologies; and (2) Set forth approved monitoring technologies. (c) (1) A person may apply to the Department of the Environment for an exception under subsection (a) of this section. (2) The Department of the Environment, in consultation with the Department of Natural Resources, may grant an exception under subsection (a) of this section to an applicant if the application sets forth compliance schedules acceptable to the Department. (d) An owner of a vessel that is equipped with a marine sanitation device that meets the requirements of 33 C.F.R. 159 shall automatically be excepted from the provisions of subsection (a) of this section.