Wisconsin Administrative Code › Department of Natural Resources › NR 200-299 - Environmental Protection - Wisconsin Pollutant Discharge Elimination System › Chapter NR 204 - Domestic sewage sludge management › Section NR 204.03 - Definitions

Current through June 24, 2024
The following definitions are applicable to terms used in
				  this chapter. Definitions of other terms and the meaning of abbreviations are
				  in ch. NR 205.
(1) "Aerobic digestion"
				means the biochemical decomposition of organic matter in sewage sludge into
				carbon dioxide and water by microorganisms in the presence of air.
(2) "Agricultural land" means land on which a
				food crop, a feed crop or fiber crop will be grown within 12 months following
				sludge application. This includes range land and land used as
				pasture.
(3) "Agronomic rate" means
				the whole sludge application rate, on a dry weight basis, designed to provide
				the amount of nitrogen needed by the food crop, feed crop, fiber crop, cover
				crop or vegetation grown on the land, and designed to minimize the amount of
				nitrogen in the sewage sludge that passes below the root zone of the crop or
				vegetation grown on the land to the groundwater.
(4) "Anaerobic digestion" means the
				biochemical decomposition of organic matter in sewage sludge into methane gas
				and carbon dioxide by microorganisms in the absence of air.
(5) "Annual pollutant loading rate" means the
				maximum amount of a pollutant that can be applied to a unit area of land during
				a 365-day period.
(6) "Application
				rate" means the loading limits placed on a landspreading site, as established
				by the agronomic needs of the crop and the characteristics of the sludge,
				normally expressed as dry tons/acre, gallons/acre or cu yd/acre.
(7) "Available nitrogen" means the nitrogen
				which is present in the sludge in the NH3-N form and the nitrogen that is
				mineralized from the organic nitrogen in the sludge; both of which can then be
				absorbed and assimilated by growing plants in the cropping year.
(8) "Bag or other container" or "bagged" or
				"bag" means either a bag or an open or closed receptacle that has a capacity of
				one metric ton or less. This includes a bucket, a box, a carton and a vehicle
				or trailer.
(9) "Bedrock" means the
				rocks that underlie soil material. Bedrock may be present at the earth's
				surface when the weathered in-place consolidated material, larger than 2 mm in
				size, is greater than 50% by volume.
(10) "Bulk sewage sludge" means sewage sludge
				which will be applied to the land but is not bagged.
(11) "Centralized septage treatment facility"
				means a treatment facility which accepts septage from multiple sources and
				treats the septage prior to discharge or disposal.
(12) "Community well" means a public well
				which serves at least 15 service connections used by year-round residents or
				regularly serves at least 25 year- round residents. Any well serving 7 or more
				homes, 10 or more mobile homes, 10 or more apartment units or 10 or more
				condominium units shall be considered a community well unless information is
				available to indicate that 25 year- round residents will not be
				served.
(13) "Cumulative metals
				loading rate" means the maximum amount of an inorganic metal that can be
				applied to a unit area of land.
(14) "Density of microorganisms" means the
				number of microorganisms per unit mass of total solids, on a dry weight basis,
				in the sewage sludge.
(15)
				"Department" means the department of natural resources.
(16) "Detrimental effects" means
				contamination of the lands or waters of the state or making the same injurious
				to public health, harmful for commercial or agricultural use, or deleterious to
				animal or plant life.
(17)
				"Domestic sewage" means waste and wastewater from humans or household
				operations that is discharged to or otherwise enters a treatment
				works.
(18) "Dry run" means a
				drainage pathway, either natural or artificial, with definable banks, which
				contains confined flow during periods of natural runoff.
(19) "Exceptional quality sludge" means
				sludge that meets the class A requirements for pathogens, as specified in s.
				NR 204.07(6)
				(a), the high quality pollutant
				concentrations, as specified in s.
				NR 204.07(5)
				(c), and one of the pre-land application
				processes to reduce vector attraction, as specified in s.
				NR 204.07(7) (a) to
				(i).
(20) "Feed crops" means crops produced
				primarily for consumption for animals.
(21) "Field" means a subset of a
				site.
(22) "Floodplain" means the
				land which has been or may be covered by flood water during the regional flood
				as specified under s.
				NR
				116.03(16) and (41).
(23) "Food crops" means tobacco and crops
				grown for human consumption.
(24)
				"Generator" means either the person who generates or prepares sludge during the
				treatment of domestic sewage in a treatment works or the person who derives a
				material from sludge or the person who changes the sludge characteristics
				either through treatment, mixing or any other process.
(25) "Geometric mean" means the average of
				the log values of the colony density and taking the antilog of that value, or
				by taking the nth root of the products of the n values, i.e., (Y10Y20Y
				30.....Yn) to the 1/nth power.
(26)
				"Grit" means the heavy solid materials such as sand, gravel and cinders
				collected from the headwork of a treatment system.
(27) "Groundwater" means any of the waters of
				the state, as defined in ss.
				281.01(18)
				and
				283.01(20),
				Stats., occurring in a saturated subsurface geological formation of permeable
				rock or soil.
(28) "High
				groundwater level" means the higher of either the elevation to which the soil
				is saturated as observed as a free water surface in an unlined hole or the
				elevation to which the soil has been seasonally or periodically saturated as
				indicated by soil color patterns throughout the soil profile.
(29) "High quality sludge" means sludge that
				meets the monthly average pollutant concentration limits which are shown, as
				Table 3, in s.
				NR 204.07(5)
				(c).
(30) "Historical site" means any property as
				established under s.
				44.40(2)
				(a), Stats.
(31) "Incorporation" means the mixing of
				sludge with topsoil to a minimum depth of 4 inches by such means as discing,
				mold-board plowing, chisel plowing, rototilling or other tillage
				methods.
(32) "Injection" means the
				subsurface placement of liquid sludge to a depth of 4 to 12 inches.
(33) "Land application" means the spraying or
				spreading of sludge onto the land surface, the injection of sludge below the
				land surface, or the incorporation of sludge into the soil. Sludge can either
				condition the soil or fertilize crops or vegetation grown in the
				soil.
(34) "Land with high
				potential for public exposure" means land that the public uses frequently. This
				includes sites such as a public contact site, a lawn or home garden, and a
				reclamation site located in a populated area, e.g., a construction site located
				in a city.
(35) "Land with low
				potential for public exposure" means land that the public uses infrequently.
				This includes agricultural land, forest and reclamation sites located in an
				unpopulated area.
(36) "Monthly
				average" means the arithmetic mean of all measurements taken during the month
				using analytical methodologies specified in ch. NR 219.
(37) "Municipal solid waste landfill" means a
				discrete area of land or an excavation that is subject to the requirements in
				chs.
				NR 500 to
				538 and is licensed to receive
				household waste, other wastes such as commercial solid waste, nonhazardous
				sludge, small quantity generator waste and industrial solid waste. It does not
				include a land application site, surface disposal unit, surface impoundment,
				injection well or waste pile.
(38)
				"Pathogens" means disease causing organisms. This includes, but is not limited
				to, certain bacteria, protozoa, viruses and viable helminth ova.
(39) "PCBs" means polychlorinated
				biphenyls.
(40) "Permeability"
				means the rate of the movement of liquid through the soil expressed in inches
				per hour.
(41) "Person" means an
				individual, owner, operator, association, partnership, corporation,
				municipality, interstate agency, state agency or federal agency.
(42) "Person who prepares sludge" means a
				generator.
(43) "pH" means the
				logarithm of the reciprocal of the hydrogen ion concentration measured at
				25° C or measured at another temperature and then converted to an
				equivalent value at 25° C.
(44)
				"POTW" or "publicly owned treatment works" means a treatment works which is
				owned by a public entity and any sewers that convey wastewater to the treatment
				works. This definition includes any device or system used by a municipality in
				the storage, treatment, recycling and reclamation of municipal sewage, sludge
				or liquid industrial waste.
(45)
				"Privately owned domestic wastewater treatment works" means a facility which
				has a permit under ch. 283, Stats., and which treats domestic wastewater or
				sludge and which is owned and operated by non-municipal entity or enterprise
				such as a mobile home park, restaurant, hotel, motel or country club.
(46) "Public contact site" means land with a
				high potential for contact by the public. This includes sites such as public
				parks, ball fields, plant nurseries, turf farms and golf courses.
(47) "Recreation area" means a designated
				area clearly identified for the purpose of providing an opportunity for
				recreational activity.
(48)
				"Reclamation site" means drastically disturbed land that is reclaimed using
				sewage sludge. This includes sites such as strip mines and construction
				sites.
(49) "Recycling" means the
				beneficial reuse of sludge through land application, composting or other
				approved method that returns organic matter or nutrients to the soil, or
				creates a useful product.
(50)
				"Research plots" means an area of land approved by the department and designed
				and operated by a qualified person to investigate questions pertaining to land
				application and uses of sludge.
(51) "Restricted public access" means private
				property or the limiting of entry, for a period of time, by means such as signs
				or traditional agricultural fencing or other department approved
				method.
(52) "School" means a
				public or private educational facility in which a program of educational
				instruction is provided to children or adults in any grade or grades from
				pre-school through the university level.
(53) "Screenings" means the coarse sewage
				solids collected from devices such as gratings, wire mesh or perforated
				plates.
(54) "Set aside land" or
				"acreage conservation reserve" means the agricultural land which is taken out
				of crop production on an annual basis for the purposes of conservation and to
				reduce the acreage planted of a particular crop.
(55) "Sewage sludge" or "sludge" or
				"biosolids" means the solid, semi-solid or liquid residue generated during the
				treatment of domestic sewage in a treatment works. Sewage sludge includes scum
				or solids removed in primary, secondary or advanced wastewater treatment
				processes and material derived from sewage sludge. Sewage sludge does not
				include ash generated during the firing of a sewage sludge incinerator or grit
				and screenings generated during preliminary treatment of domestic sewage in a
				treatment works.
Note: All 3 terms defined here are interchangeable and
				  recognized by the department, as they are all in common use.
(56) "Site" means any property used for
				recycling, disposal or storage of sludge and may be divided into
				fields.
(57) "Soil" means the
				unconsolidated material which overlies bedrock.
(58) "Soil compaction" means the degree of
				compaction to a soil at which its infiltration capacity, permeability and
				ability to function as a medium for plant growth is impeded.
(59) "Soil conservation practice" means a
				measure used to retain surface water and soil on agricultural fields, including
				contour strip cropping, terracing, grassed waterways or plant residue
				management practices.
(60) "Soil
				pH" means the pH of the soil in the plow layer as measured in water by a pH
				meter with a glass electrode or by using another department approved
				procedure.
(61) "Specific oxygen
				uptake rate" or "SOUR" means the mass of oxygen consumed per unit time per unit
				mass of total solids on a dry weight basis.
(62) "Stabilization of sludge" means any
				combination of chemical, physical, thermal or biological treatment processes
				which result in a significant reduction in the percentage of volatile solids or
				the specific oxygen uptake rate in the sludge.
(63) "Surface disposal unit" means an area of
				land on which only sewage sludge, including exceptional quality sludge, is
				placed for final disposal. This does not include land or lagoons on which
				sewage sludge is either stored or treated, municipal solid waste landfills or
				land application sites.
(64)
				"Surface water" means those portions of Lake Michigan and Lake Superior within
				the boundaries of Wisconsin, all lakes, bays, rivers, streams, springs, ponds,
				impounding reservoirs, marshes, water courses, drainage systems and other
				surface water, natural or artificial, public or private within the state or
				under its jurisdiction, except those waters which are entirely confined and
				completely retained upon the property of a facility.
(65) "Threatened or endangered species" means
				those species defined in ch. NR 27.
(66) "Total nitrogen" means the sum of
				nitrite, nitrate, ammonia and organic nitrogen.
(67) "Total solids" means the materials in
				sewage sludge that remain as residue when the sewage sludge is dried at 103 to
				105° Celsius.
(68) "Treatment
				works" means a publicly or privately owned treatment works, centralized septage
				treatment facility, and treatment works owned by federal or state
				government.
(69) "Unstabilized
				solids" means the organic materials in sewage sludge that have not been treated
				in either an aerobic or anaerobic treatment process.
(70) "Vector attraction" means the
				characteristics of sewage sludge that attract rodents, flies, mosquitos or
				other organisms capable of transporting infectious agents.
(71) "Volatile solids" means the amount of
				the total solids in sewage sludge lost when the sewage sludge is combusted at
				550° Celsius in the presence of excess air.
(72) "Wetlands" means those areas where water
				is at, near, or above the land surface long enough to be capable of supporting
				aquatic or hydrophytic vegetation, and which have soils indicative of wet
				conditions.
(73) "Wisconsin
				pollutant discharge elimination system permit" or "WPDES permit" or "permit"
				means a permit issued by the department under ch. 283, Stats., for the
				discharge of pollutants.