Classification of Wastewater Treatment Facilities

(1) Each municipal wastewater treatment facility shall be classified by the Board as either 1M, 2M, 3M, 4M or 5, 6, or 7 for large or complex facilities. Each industrial wastewater treatment facility shall be classified as either 1I, 2I, 3I, 4I, or 5, 6, or 7 for large or complex facilities. The increasing numerical class indicates increasing complexity of operation and a higher level of training, knowledge, and experience required for operation. (2) The class of a facility shall be established by adding together all rating values reflecting the complexity of operation for units which are present in the facility, as set forth below: Rating Values for Classification of Facilities Unit Rating Aeration; mechanical or diffused air greater than 0.5 MGD less than 0.5 MGD Aeration; sludge, re-aeration Aeration; pure oxygen greater than 0.5 MGD BOD Removal 1 and up* Carbon Filter Carbon absorption in an Industrial facility Carbon reactivation Centrifuge Chemical addition 2 points per chemical Chlorination pre, gas or liquid Chlorination post, gas or liquid Clarifier, tube settling or inclined plate Clariflocculation Coagulation and Neutralization Comminution Condenser Cooling Tower Dechlorination Denitrification Dissolved Air Flotation Electrodialysis Electrolytic Recovery Unit Rating Equalization Evaporators Extended Aeration greater than 0.1 MGD, less than 0.5 MGD Extended Aeration equal to or less than 0.1 MGD Flash Mixing Flow measurement Flocculation Grit Chamber, Aerated Grit Chamber manually cleaned Grit Chamber mechanical grit removal Heat Exchangers High rate filtration units less than 0.1 MGD greater than 0.1 less than 0.5 MGD greater than 0.5 less than 1.0 MGD greater than 1.0 MGD Hypochlorite generation Hypochlorination pre and/or post Hydrocyclones (grit removal) Imhoff tanks Incineration Instrumentation Ion Exchange Laboratory Land Irrigation, spraying Land Irrigation, direct discharge Membrane Filtration Nitrification Odor Control Oil Separation Oxidation Ditch Oxygen Generation Ozonation Polishing Filter Post-aeration (cascade) Post-aeration (mechanical) Pre-aeration Primary Settling; airlift or manual sludge removal Primary Settling; mechanical sludge removal Primary sludge holding and mixing Pumping (in plant) Pumping stations under operator's control Reaction Vessel Reverse osmosis Rotating Biological Contactors Unit Rating Rotating Biological Contactors; multiple stage Rotary Drum Dryers Sand filters; multi media, automatic backwash Sand filters; intermittent Sand filters; polishing Sand filters; subsurface Screens (mechanical) Scum Concentrator Secondary settling; airlift or manual sludge removal Secondary settling; mechanical sludge removal Septage facilities Sludge blending Sludge composting Sludge drying beds Sludge digestion; aerobic Sludge digestion; heated and mixed anaerobic Sludge digestion; heated and unmixed, anaerobic Sludge digestion; unheated Sludge elutriation Sludge incinerators Sludge press; belt Sludge press; plate and frame Sludge storage Sludge thickeners; gravity Sludge thickeners; flotation Stabilization ponds; non-aerated Stabilization ponds; aerated Stripping Air Steam Trickling filters; high rate Trickling filters; staged Trickling filters; standard rate Ultraviolet disinfection Vacuum filter Wet Air Oxidation Design BOD in Pounds/Day x "f" * BOD Removal Rating = "f" = 0.3 for primary treatment and 0.8 for secondary or higher facilities. (3) Wastewater treatment facilities shall be classified according to the following cumulative rating value: Class Cumulative Rating Value Class 1 (M or I) Class 2 (M or I) Class 3 (M or I) Class 4 (M or I) Class 5 (C) Class 6 (C) Class 7 (C) 81 or more (4) Class 1 (I) and Class 2 (I) facilities which have fewer than three units or a rating of 20 or fewer points shall be considered Type I facilities for the purposes of 310 CMR 4.00. (5) Class 1 (I) and Class 2 (I) facilities with greater than three units or a rating of more than 20 points and Class 3 (I), Class 4 (I), Class 5, Class 6, and Class 7 facilities shall be considered Type II facilities for the purposes of 310 CMR 4.00. (6) The Board may establish a rating value for any unit not shown on the table. The Board may change the classification of a particular wastewater treatment facility when there are site-specific factors affecting the complexity of the treatment process.