Md. Code, Env't § 9-101

(a) In this title the following words have the meanings indicated. (b) “Discharge” means: (1) The addition, introduction, leaking, spilling, or emitting of a pollutant into the waters of this State; or (2) The placing of a pollutant in a location where the pollutant is likely to pollute. (c) (1) “Disposal system” means a system for disposing of wastes by surface, above surface, or underground methods. (2) “Disposal system” includes a treatment works and a disposal well. (d) (1) “Effluent limitation” means a restriction or prohibition that: (i) Is established under federal law or a law of this State; and (ii) Specifies quantities, rates, or concentrations of chemical, physical, biological, or other constituents that are discharged into the waters of this State. (2) “Effluent limitation” includes: (i) Parameters for toxic and nontoxic discharges; (ii) Standards of performance for new sources; and (iii) Ocean discharge standards. (d–1) “Failing on–site sewage disposal system” means an on–site sewage disposal system or a cesspool, or a component of an on–site sewage disposal system or a cesspool, that is a threat to public health due to: (1) The potential for direct contact between sewage and members of the public; (2) A failure to prevent: (i) Sewage from reaching the surface of the ground; (ii) Sewage from backing up into a structure due to slow soil absorption of sewage effluent; (iii) Sewage from leaking from a sewage tank or collection system; (iv) Unless specifically authorized by a groundwater protection report approved by the Department before January 1, 2019, groundwater degradation; or (v) Surface water degradation; or (3) For a permitted on–site sewage disposal system, significant noncompliance with the standards and conditions of the on–site sewage disposal system permit. (e) “Industrial user” means: (1) A person who is engaged in manufacturing, fabricating, or assembling goods; or (2) A member of any class of significant producers of pollutants identified under rules or regulations adopted by: (i) The Secretary; or (ii) The administrator of the United States Environmental Protection Agency. (f) “National pollutant discharge elimination system” means the national system for issuing permits as designated by the Federal Water Pollution Control Act. (g) “Pollutant” means: (1) Any waste or wastewater that is discharged from: (i) A publicly owned treatment works; or (ii) An industrial source; or (2) Any other liquid, gaseous, solid, or other substance that will pollute any waters of this State. (h) “Pollution” means any contamination or other alteration of the physical, chemical, or biological properties of any waters of this State, including a change in temperature, taste, color, turbidity, or odor of the waters or the discharge or deposit of any organic matter, harmful organism, or liquid, gaseous, solid, radioactive, or other substance into any waters of this State, that will render the waters harmful or detrimental to: (1) Public health, safety, or welfare; (2) Domestic, commercial, industrial, agricultural, recreational, or other legitimate beneficial uses; (3) Livestock, wild animals, or birds; or (4) Fish or other aquatic life. (i) “Publicly owned treatment works” means a facility that is: (1) Owned by this State or a political subdivision, municipal corporation, or other public entity; and (2) Used for the treatment of pollutants. (j) (1) “Solid waste” means any garbage, refuse, sludge, or liquid from industrial, commercial, mining, or agricultural operations or from community activities. (2) “Solid waste” includes: (i) Scrap tires as defined in § 9–201 of this title; (ii) Organic material capable of being composted that is not composted in accordance with regulations adopted under § 9–1725(b) of this title; (iii) Materials that are managed at a recycling facility and are not recyclable materials as defined in § 9–1701 of this title; and (iv) Recyclable materials as defined in § 9–1701 of this title that are not: 1. Returned to the marketplace in the form of a raw material or product within 1 calendar year from the time the recyclable materials are received; or 2. Otherwise managed in accordance with regulations adopted under § 9–1713 of this title. (3) “Solid waste” does not include: (i) Solid or dissolved material in domestic sewage or in irrigation return flows; (ii) Compost as defined in § 9–1701 of this title; (iii) Organic material capable of being composted that is composted in accordance with regulations adopted under § 9–1725(b) of this title; or (iv) Materials that are managed at a recycling facility in accordance with regulations adopted under § 9–1713 of this title. (k) “Water quality standard” means a water quality standard that is adopted and effective under federal law or a law of this State. (l) “Waters of this State” includes: (1) Both surface and underground waters within the boundaries of this State subject to its jurisdiction, including that part of the Atlantic Ocean within the boundaries of this State, the Chesapeake Bay and its tributaries, and all ponds, lakes, rivers, streams, public ditches, tax ditches, and public drainage systems within this State, other than those designed and used to collect, convey, or dispose of sanitary sewage; and (2) The flood plain of free–flowing waters determined by the Department of Natural Resources on the basis of the 100–year flood frequency.