§9–353.

    (a)    In this part the following words have the meanings indicated.

    (b)    (1)    “Industrial user” means:

            (i)    A person who is engaged in manufacturing, fabricating, or assembling goods; or

            (ii)    A member of any class of significant producers of pollutants identified under regulations adopted by:

                1.    The Secretary; or

                2.    The Administrator of the U.S. Environmental Protection Agency.

        (2)    “Industrial user” does not include the federal, State, and local governments.

    (c)    “PFAS chemicals” means a class of fluorinated organic chemicals that contain at least one fully fluorinated carbon atom, including perfluoroalkyl and polyfluoroalkyl substances.

    (d)    “Pretreatment permit” means a document issued by the Department or the Department’s designee that authorizes a significant industrial user to introduce industrial wastes into a publicly owned treatment works in compliance with the pretreatment requirements under COMAR 26.08.01.01B(69).

    (e)    (1)    “Significant industrial user” means an industrial user that:

            (i)    Is subject to categorical pretreatment standards under 40 C.F.R. Part 403.6;

            (ii)    Discharges an average of 25,000 gallons per day or more of processed wastewater to a publicly owned treatment works, not including sanitary, noncontact cooling, and boiler blowdown wastewater;

            (iii)    Contributes processed wastewater that makes up 5% or more of the average dry–weather hydraulic or organic capacity of the publicly owned treatment works; or

            (iv)    Is designated as a significant industrial user by the publicly owned treatment works on the basis that the industrial user has:

                1.    A reasonable potential for adversely affecting the wastewater treatment plant’s operations and sewer system; or

                2.    Violated a pretreatment standard or requirement.

        (2)    “Significant industrial user” does not include the federal, State, and local governments.

    (f)    “Waters of the State” include:

        (1)    Both surface and underground waters within the boundaries of the State subject to its jurisdiction;

        (2)    That portion of the Atlantic Ocean within the boundaries of the State;

        (3)    The Chesapeake Bay and its tributaries;

        (4)    All ponds, lakes, rivers, streams, public ditches, tax ditches, and public drainage systems within the State, other than those designed and used to collect, convey, or dispose of sanitary sewage; and

        (5)    The floodplain of free–flowing waters determined by the Department on the basis of the 100–year flood frequency.