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

2. (b)

   1. (1) “Industrial user” means:

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

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

         1. 1. The Secretary; or
         2. 2. The Administrator of the U.S. Environmental Protection Agency.
   2. (2) “Industrial user” does not include the federal, State, and local governments.
3. (c) “PFAS chemicals” means a class of fluorinated organic chemicals that contain at least one fully fluorinated carbon atom, including perfluoroalkyl and polyfluoroalkyl substances.
4. (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).

5. (e)

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

      1. (i) Is subject to categorical pretreatment standards under 40 C.F.R. Part 403.6;
      2. (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;
      3. (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

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

         1. 1. A reasonable potential for adversely affecting the wastewater treatment plant's operations and sewer system; or
         2. 2. Violated a pretreatment standard or requirement.
   2. (2) “Significant industrial user” does not include the federal, State, and local governments.

6. (f) “Waters of the State” includes:

   1. (1) Both surface and underground waters within the boundaries of the State subject to its jurisdiction;
   2. (2) That portion of the Atlantic Ocean within the boundaries of the State;
   3. (3) The Chesapeake Bay and its tributaries;
   4. (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. (5) The floodplain of free-flowing waters determined by the Department on the basis of the 100-year flood frequency.

Added by Acts 2024, c. 556, § 1, eff. July 1, 2024; Acts 2024, c. 557, § 1, eff. July 1, 2024. Amended by Acts 2025, c. 142, § 1, eff. April 22, 2025.