314 CMR 4.02 - Definitions
Aquatic Life. A native, naturally diverse, community of aquatic flora and fauna including, but not limited to, wildlife and threatened and endangered species.
Authorization. An approval granted pursuant to 314 CMR 4.04(5) for a discharge to High Quality Waters, Outstanding Resource Waters or Special Resource Waters.
Background Conditions. That water quality which exists or would exist in the absence of pollutants requiring permits and other controllable cultural factors that are subject to regulation under M.G.L. c. 21, §§ 26 through 53.
Best Available Treatment Technology. The technology-based standard of the Clean Water Act defined as Best Available Technology Economically Achievable (BAT) for privately-owned treatment works. BAT effluent limitation guidelines reflect the best performance technologies for a particular pollutant or group of pollutants, or for a category or class of point sources, that are economically achievable.
Best Management Practices or BMPs. Schedules of activities, prohibitions of practices, maintenance procedures, and other management practices to prevent or reduce the discharge of pollutants to waters of the Commonwealth. BMPs include treatment requirements, operating procedures, structures, devices, and/or practices to control plant site runoff, spillage, or leaks, sludge or waste disposal, or drainage from raw material storage.
Best Professional Judgment. The method used by the Department to develop technology-based Surface Water Discharge Permit Conditions on a case by case basis using all reasonably available and relevant data.
Biological Integrity. The capability of supporting and maintaining a balanced, integrated, adaptive community of organisms having species composition, diversity, and functional organization comparable to that of the natural habitat of the region.
Class A Waters or Class A. Those Inland Waters so designated pursuant to 314 CMR 4.06; including, without limitation, 314 CMR 4.06(1)(d)1. and (4) as public water supplies and their tributaries; certain wetlands designated in 314 CMR 4.06(2); certain reservoirs designated in 314 CMR 4.06(3); and certain surface waters designated in 314 CMR 4.06(6)(b). They are designated as excellent habitat for fish, other aquatic life and wildlife, including for their reproduction, migration, growth and other critical functions, and for primary and secondary contact recreation, even if not allowed. These waters shall have excellent aesthetic value. These waters are protected as Outstanding Resource Waters.
Class B Waters or Class B. Those Inland Waters so designated pursuant to 314 CMR 4.06; including, without limitation, certain wetlands designated in 314 CMR 4.06(2), certain other waters designated in 314 CMR 4.06(5), and certain qualified waters designated in 314 CMR 4.06(6)(b). These waters are designated as a habitat for fish, other aquatic life, and wildlife, including for their reproduction, migration, growth and other critical functions, and for primary and secondary contact recreation. Where designated in 314 CMR 4.06(1)(d)6. and (6)(b) as a "Treated Water Supply" these waters shall be suitable as a source of public water supply with appropriate treatment. Class B waters shall be suitable for irrigation and other agricultural uses and for compatible industrial cooling and process uses. These waters shall have consistently good aesthetic value.
Class B (CSO). Those Class B partial use Inland Waters so designated in accordance with 314 CMR 4.06(1)(d)11. and (6)(b).
Class C Waters or Class C. These Inland Waters are designated as a habitat for fish, other aquatic life and wildlife, including for their reproduction, migration, growth and other critical functions, and for secondary contact recreation. These waters shall be suitable for the irrigation of crops used for consumption after cooking and for compatible industrial cooling and process uses. These waters shall have good aesthetic value.
Class SA Waters or Class SA. Those Coastal and Marine Waters so designated pursuant to 314 CMR 4.06; including, without limitation, 314 CMR 4.06(2) and (5), and certain qualified waters designated in 314 CMR 4.06(6)(b). These waters are designated as an excellent habitat for fish, other aquatic life and wildlife, including for their reproduction, migration, growth and other critical functions, and for primary and secondary contact recreation. In certain waters, excellent habitat for fish, other aquatic life and wildlife may include, but is not limited to, seagrass. Where designated for shellfishing in 314 CMR 4.06(6)(b), these waters shall be suitable for shellfish harvesting without depuration (Approved and Conditionally Approved Shellfish Areas). These waters shall have excellent aesthetic value.
Class SB Waters or Class SB. Those Coastal and Marine Waters so designated pursuant to 314 CMR 4.06; including, without limitation, 314 CMR 4.06(2) and certain surface waters designated in 314 CMR 4.06(6)(b). These waters are designated as a habitat for fish, other aquatic life and wildlife, including for their reproduction, migration, growth and other critical functions, and for primary and secondary contact recreation. In certain waters, habitat for fish, other aquatic life and wildlife may include, but is not limited to, seagrass. Where designated for shellfishing in 314 CMR 4.06(6)(b), these waters shall be suitable for shellfish harvesting with dupuration (Restricted and Conditionally Restricted Shellfish Areas). These waters shall have consistently good aesthetic value.
Class SB (CSO). Those Class SB partial use Coastal and Marine Waters so designated in accordance with 314 CMR 4.06(1)(d)11. and (6)(b).
Class SC Waters or Class SC. These Coastal and Marine Waters are designated as a habitat for fish, other aquatic life and wildlife, including for their reproduction, migration, growth and other critical functions, and for secondary contact recreation. They shall also be suitable for certain industrial cooling and process uses. These waters shall have good aesthetic value.
Coastal and Marine Waters. The Atlantic Ocean and all contiguous saline bays, inlets and harbors within the jurisdiction of the Commonwealth including areas where fresh and salt waters mix and tidal effects are evident or any partially enclosed coastal body of water where the tide meets the current of a stream or river.
Cold Water Fishery. Waters in which the mean of the maximum daily temperature over a seven day period generally does not exceed 68°F (20°C) and, when other ecological factors are favorable (such as habitat), are capable of supporting a year-round population of cold water stenothermal aquatic life such as trout (Salmonidae).
Combined Sewer Overflow or CSO. Any intermittent overflow, bypass or other discharge from a municipal combined sewer system which results from a wet-weather flow in excess of the dry-weather carrying capacity of the system.
Criteria. Elements of state water quality standards, expressed as constituent concentrations, levels, or narrative statements, representing a quality of water that supports a use.
Cultural Eutrophication. The human-induced increase in nutrients resulting in acceleration of primary productivity, which causes nuisance conditions, such as algal blooms or dense and extensive macrophyte growth, in a waterbody.
Department or MassDEP. The Massachusetts Department of Environmental Protection.
Designated Use. Those uses specified in 314 CMR 4.05 and 314 CMR 4.06 for each water Class whether or not they are being attained.
Discharge of Pollutants. Any addition of any pollutant or combination of pollutants to the waters of the Commonwealth from any source.
EPA. The United States Environmental Protection Agency.
Epilimnion. The upper circulating layer of a stratified lake or pond.
Existing Use. Those designated uses and any other uses that do not impair the designated uses that are actually attained in a waterbody on or after November 28, 1975; except that in no case shall assimilation or transport of pollutants be considered an existing use.
Federal Act. The Federal Water Pollution Control Act (FWPCA), currently known as the Clean Water Act, 33 U.S.C. § 1251 et seq.
Harmonic Mean Flow. A long-term flow value calculated by dividing the number of daily flows analyzed by the sum of the reciprocals of those daily flows.
Highest and Best Practical Treatment or HBPT. The best practicable waste treatment technology for publicly-owned treatment works that is the most appropriate means available on a regional basis for controlling the direct discharge of toxic and nonconventional pollutants to navigable waters. HBPT effluent limitation guidelines reflect the best performance technologies for a particular pollutant or group of pollutants that are economically achievable.
Inland Waters or Fresh Waters. Any surface water not subject to tidal action or not subject to the mixing of fresh and ocean waters.
Lakes and Ponds. Waterbodies having open water, situated in a topographical depression, generally with a maximum depth of greater than two meters. Lakes and ponds do not include constructed stormwater retention basins, constructed impervious basins or impervious impoundments, permitted wastewater lagoons, constructed farm ponds into which and from which no stream or river flows, and generally do not include dammed river or stream impoundments. The Department may determine, on a case by case basis, that a shallower waterbody or a dammed river or stream impoundment is a lake or pond based on aquatic and other resources or uses to be protected.
Massachusetts Act. The Massachusetts Clean Waters Act, M.G.L. c. 21, §§ 26 through 53.
National Goal Uses. Propagation of fish, shellfish other aquatic life and wildlife and recreation in and on the water in accordance with 33 U.S.C. § 1251 et seq.
New or Increased Discharge. Any discharge which commences after the date 314 CMR 4.00 initially became effective; any discharge requiring a permit which is unpermitted and commenced prior to the date 314 CMR 4.00 became effective; and any increase in discharges except for an increase in conformance with a currently valid permit.
Nonpoint Source. Any source of pollutant discharge that is not a point source.
Outstanding Resource Waters or ORW. Waters designated for protection in 314 CMR 4.06, which include Class A Public Water Supplies (314 CMR 4.06(1)(d)1.) and their tributaries, certain wetlands as specified in 314 CMR 4.06(2), certain surface waters designated in 314 CMR 4.06(6)(b), and other waters as determined by the Department based on their outstanding socio-economic, recreational, ecological and/or aesthetic values.
Point Source. Any discernable, confined and discrete conveyance, including but not limited to any pipe, ditch, channel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, vessel or other floating craft, from which pollutants are or may be discharged. Point Source does not include return flows from irrigated agriculture.
Pollutant. Any element or property of sewage, agricultural, industrial or commercial waste, runoff, leachate, heated effluent, or other matter in whatever form, and whether originating at a point or nonpoint source, that is or may be discharged, drained or otherwise introduced into any sewage system, treatment works or waters of the Commonwealth.
Primary Contact Recreation. Any recreation or other water use in which there is prolonged and intimate contact with the water with a significant risk of ingestion of water. These include, but are not limited to, wading, swimming, diving, surfing and water skiing.
Publicly-owned Treatment Works or POTW shall have the meaning as defined in 314 CMR 3.02: Publicly-owned Treatment Works or POTW.
Rivers and Streams. Waterbodies contained within a channel (naturally or artificially created) which periodically or continuously contains flowing water or forms a connecting link between two bodies of standing water.
Secondary Contact Recreation. Any recreation or other water use in which contact with the water is either incidental or accidental. These include, but are not limited to, fishing, including human consumption of fish, boating and limited contact incident to shoreline activities. Where designated, secondary contact recreation also includes shellfishing, including human consumption of shellfish.
Segment. A finite portion of a waterbody established by the Department for the purpose of classification.
Site-specific Criteria. Site-specific criteria are criteria that apply to a particular surface water or segment, as set forth in 314 CMR 4.06(6)(c): Table 28: Site-specific Criteria.
Source Reduction. In-plant changes in production processes or raw materials that reduce, avoid or eliminate the use of pollutants including, but not limited to, toxic or hazardous substances, or generation of pollution by-product per unit of product, so as to reduce risks overall to the environment. Also compliance with M.G.L. c. 21I: Toxics Use Reduction Act, to the extent required by such law.
Special Resource Waters or SRW. Waters of exceptional significance, such as waters in national or State parks and wildlife refuges, so designated by the Department pursuant to 314 CMR 4.06(1)(d)3. and (6)(b).
Surface Waters. All waters other than groundwaters within the jurisdiction of the Commonwealth including, without limitation, rivers, streams, lakes, ponds, springs, impoundments, estuaries, wetlands, coastal waters and vernal pools.
Total Maximum Daily Load or TMDL. The sum of a receiving water's individual waste load allocations and load allocations and natural background, which, together with a margin of safety that takes into account any lack of knowledge concerning the relationship between effluent limitations and water quality, represents the maximum amount of a pollutant that a waterbody can receive and still meet water quality standards in all seasons.
Toxic Pollutants. Any pollutant or combination of pollutants, including disease causing agents, that are capable of producing an adverse effect in an organism or its offspring, including food chain effects, according to information available to the Department. The effect may be the result of direct or indirect exposure and may injure structure, function or cause death to the organism. These pollutants include, but are not limited to, those identified in 314 CMR 3.17: Appendix B - Toxic Pollutants.
Treatment Works shall have the meaning as defined in 314 CMR 3.02: Treatment Works.
Use Attainability Analysis or UAA. A structured scientific assessment of the factors affecting the attainment of a use, which may include physical, chemical, biological, and economic factors as described in 40 CFR 131.10(g).
Variance. A temporary modification of the surface water quality standards issued pursuant to 314 CMR 4.03(4).
Vernal Pool. A waterbody that has been certified by the Massachusetts Division of Fisheries and Wildlife as a vernal pool. Vernal pools are confined basin depressions which, at least in most years, hold water for a minimum of two continuous months during the spring and/or summer, and which are free of adult fish populations.
Warm Water Fishery. Waters in which the maximum mean monthly temperature generally exceeds 68°F (20°C) during the summer months and are not capable of sustaining a year-round population of cold water stenothermal aquatic life.
Waters of the Commonwealth. All waters within the jurisdiction of the Commonwealth, including, without limitation, rivers, streams, lakes, ponds, springs, impoundments, estuaries, wetlands, coastal waters, groundwaters, and vernal pools.
Notes
State regulations are updated quarterly; we currently have two versions available. Below is a comparison between our most recent version and the prior quarterly release. More comparison features will be added as we have more versions to compare.