Section 327IAC5-22-5. Classification of wastewater treatment plants; industrial treatment plants

   (a) An industrial wastewater treatment plant shall be classified into one (1) of five (5) classifications based on the type of treatment provided, design population equivalent, and the average daily flow according to the following:

(1) Class A-SO includes wastewater treatment plants having one (1) or more of the following:

(A) Primary solids removal facilities, such as:

(i) settling tanks;

(ii) settling ponds;

(iii) sand filters; or

(iv) screens;

used only for removal of settleable inorganic solids.

(B) Tanks, ponds, centrifuges, or other facilities used to separate floatable oils and solids.

(C) pH adjustment.

Wastewater flow is not a limiting factor in the Class A-SO classification of industrial wastewater treatment plant.

(2) Class A includes wastewater treatment plants having one (1) or more of the following:

(A) Secondary treatment facilities that treat wastewater loads of less than two thousand (2,000) design population equivalent, such as:

(i) waste stabilization ponds whether anaerobic or aerobic;

(ii) trickling filter;

(iii) activated sludge-type treatment plants;

(iv) aerated lagoons; or

(v) other biological treatment facilities.

(B) Spray, broad, or ridge and furrow irrigation facilities that treat a wastewater flow of less than two hundred thousand (200,000) gallons per day.

(3) Class B includes wastewater treatment plants having one (1) or more of the following:

(A) Secondary treatment facilities that treat wastewater loads equal to or greater than two thousand (2,000) design population equivalent and less than ten thousand (10,000) design population equivalent, such as:

(i) waste stabilization ponds whether anaerobic or aerobic;

(ii) trickling filter;

(iii) activated sludge-type treatment plants;

(iv) aerated lagoons; or

(v) other biological treatment facilities.

(B) Spray, broad, or ridge and furrow irrigation facilities that treat a wastewater flow equal to or greater than two hundred thousand (200,000) gallons per day and less than one million (1,000,000) gallons per day.

(C) Chemical treatment facilities that process or treat wastewater flow of less than fifty thousand (50,000) gallons per day using one (1) of the following methods:

(i) Cyanide destruction.

(ii) Chromium reduction.

(iii) Coagulation and flocculation.

(iv) Air flotation.

(v) Air stripping.

(vi) Wet air oxidation.

(vii) Activated carbon filtration.

(viii) Membrane filtration.

(ix) Steam stripping.

(4) Class C includes wastewater treatment plants having one (1) or more of the following:

(A) Secondary treatment facilities that treat wastewater loads equal to or greater than ten thousand (10,000) design population equivalent and less than forty thousand (40,000) design population equivalent, such as:

(i) waste stabilization ponds whether anaerobic or aerobic;

(ii) trickling filter;

(iii) activated sludge-type treatment plants;

(iv) aerated lagoons; or

(v) other biological treatment facilities.

(B) Spray, broad, or ridge and furrow irrigation facilities that treat a wastewater flow equal to or greater than one million (1,000,000) gallons per day and less than four million (4,000,000) gallons per day.

(C) Chemical treatment facilities that process or treat wastewater flow equal to or greater than fifty thousand (50,000) gallons per day and less than two hundred thousand (200,000) gallons per day using one (1) of the following methods:

(i) Cyanide destruction.

(ii) Chromium reduction.

(iii) Coagulation and flocculation.

(iv) Air flotation.

(v) Air stripping.

(vi) Wet air oxidation.

(vii) Activated carbon filtration.

(viii) Membrane filtration.

(ix) Steam stripping.

(5) Class D includes wastewater treatment plants having one (1) or more of the following:

(A) Secondary treatment facilities that treat wastewater loads equal to or greater than forty thousand (40,000) design population equivalent, such as:

(i) waste stabilization ponds whether anaerobic or aerobic;

(ii) trickling filter;

(iii) activated sludge-type treatment plants;

(iv) aerated lagoons; or

(v) other biological treatment facilities.

(B) Chemical treatment facilities that process or treat a wastewater flow equal to or greater than two hundred thousand (200,000) gallons per day using one (1) of the following methods:

(i) Cyanide destruction.

(ii) Chromium reduction.

(iii) Coagulation and flocculation.

(iv) Air flotation.

(v) Air stripping.

(vi) Wet air oxidation.

(vii) Activated carbon filtration.

(viii) Membrane filtration.

(ix) Steam stripping.

(C) Deep well disposal systems, thermal evaporators, or incinerators used in conjunction with liquid waste disposal.

(D) Two (2) or more industrial wastewater treatment plants at one (1) industrial site if each independent industrial wastewater treatment plant is classified as a Class B or C wastewater treatment plant.

(E) An industry utilizing a highly complex wastewater treatment method.

  (b) If an industrial wastewater treatment plant has more than one (1) treatment process despite having only one (1) wastewater treatment plant, that industrial wastewater treatment plant shall be classified into the classification of the most complex component of wastewater treatment performed in relation to the following factors:

(1) Secondary treatment PE.

(2) Spray irrigation volume.

(3) Chemical treatment volume.

(Water Pollution Control Division; 327 IAC 5-22-5; filed Nov 20, 2000, 4:07 p.m.: 24 IR 964; readopted filed Aug 17, 2006, 10:31 a.m.: 20060830-IR-327060183BFA; filed Mar 18, 2008, 2:55 p.m.: 20080416-IR-327060179FRA; readopted filed Jul 30, 2014, 4:04 p.m.: 20140827-IR-327140189BFA)