NR 110.03(12g)(12g) “Design flow” means the anticipated wastewater discharge rate to a sewerage system component, which is used to design the sewerage system component to provide compliance with WPDES permit limits and other performance objectives, during the most critical operating conditions anticipated within the design planning period. Specific design flow terms used in this chapter, include the following:

NR 110.03(12g)(a)(a) “Average daily base flow” means the average of the daily flow volumes anticipated to occur for a continuous 12-month period, less infiltration and inflow, and expressed as a daily average.

NR 110.03(12g)(b)(b) “Average design flow” means the average of the daily flow volumes anticipated to occur for a continuous 12-month period, expressed as a daily average.

NR 110.03(12g)(c)(c) “Maximum month design flow” means the largest volume of flow anticipated to occur during a continuous 30-day period, expressed as a daily average.

NR 110.03(12g)(f)(f) “Maximum hour design flow” means the largest volume of flow anticipated to occur during a one-hour period, expressed as a daily or hourly average.

NR 110.03(12g)(h)(h) “Peak design flow” and “maximum design flow” mean the largest volume of flow anticipated to occur on an infrequent basis, expressed as a daily average. The “peak design flow” or “maximum design flow” may be equal to any one of the design flows defined in pars. (c) to (g).

NR 110.03(12m)(12m) “Design management zone” or “DMZ” means a 3-dimensional area, bounded by a set horizontal distance from the application or containment area, as specified in Table 4, ch. NR 140, and by variable vertical distance which extends from the land surface downward through all saturated formations.

NR 110.03(13)(13) “Dry land access” means a sewage treatment facility service road which has a minimum elevation of at least one foot above the regional flood elevation.

NR 110.03(13c)(13c) “Excessive infiltration/inflow” means the quantities of infiltration/inflow which can be economically eliminated from a sewerage system by rehabilitation, as determined in a cost-effectiveness analysis that compares the cost of correcting the infiltration/inflow conditions to the total costs for transportation and treatment of the infiltration/inflow.

NR 110.03(13e)(13e) “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.

NR 110.03(13t)(13t) “Highest anticipated groundwater elevation” means the sum of the calculated mounding effects of the disposal discharge and the seasonal high groundwater level.

NR 110.03(14e)(14e) “Hydraulic application rate” means the average daily volume of effluent discharged to a designed acreage of the land application system during a calendar month or other period of time specified in a WPDES permit. The rate is calculated by dividing the total discharge volume for the month or period of time by the acreage of land and by the number of days in the month or period of time, usually expressed in units of gallons per acre per day. For overland flow systems, the hydraulic application rate is expressed as a flow rate per unit width of slope per day.

NR 110.03(14t)(14t) “Hydrogeologist” means a person who is a graduate of an accredited institution of higher education and who has successfully completed 30 semester hours or 45 quarter hours of course work in geology. At least 6 semester hours or 9 quarter hours of the geology course work must be in hydrogeology, geohydrology or groundwater geology. This person shall also have acquired through education and actual field experience the ability to direct the drilling of borings, and the installation and development of wells; describe and classify geology samples and evaluate and interpret geologic and hydrogeologic data in accordance with the requirements of chs. NR 110 and 206.

NR 110.03(15)(a)(a) Any nongovernmental, nonresidential user of a municipally owned sewerage system which discharges more than the equivalent of 25,000 gallons per day (gpd) of sanitary wastes and which is identified in the Standard Industrial Classification Manual, 1972, United States Office Management and Budget, as amended and supplemented as of October 1, 1978 under one of the following divisions:

Division A. Agriculture, Forestry, and Fishing
Division B. Mining
Division D. Manufacturing
Division E. Transportation, Communications, Electric,
Gas, and Sanitary Services
Division I. Services.

NR 110.03(15)(a)1.1. In determining the amount of a user’s discharge, domestic wastes or discharges from sanitary conveniences may be excluded.

NR 110.03(15)(a)2.2. After applying the sanitary waste exclusion in subd. 1., discharges in the above divisions that have a volume exceeding 25,000 gpd or the weight of biochemical oxygen demand (BOD) or suspended solids (SS) equivalent to that weight found in 25,000 gpd of sanitary waste are considered industrial users. Sanitary wastes, for purposes of this calculation of equivalency, are the wastes discharged from residential users. The municipality shall, with the department’s approval, define the strength of the residential waste discharges in terms of parameters including biochemical oxygen demand (BOD) and suspended solids (SS) per volume of flow as a minimum. Dischargers with a volume exceeding 25,000 gpd or the weight of BOD or SS equivalent to that weight found in 25,000 gpd of sanitary waste are considered as industrial users.

NR 110.03(15)(b)(b) Any nongovernmental user of a municipally owned sewerage system which discharges wastewater to the sewerage system which contains toxic pollutants or poisonous solids, liquids, or gases in sufficient quantity either singly or by interaction with other wastes, to contaminate the sludge of any municipal system, or injure or interfere with any sewage treatment process, constitutes a hazard to humans or animals, creates a public nuisance, or creates any hazard in or has an adverse effect on the waters receiving any discharge from the treatment works;

NR 110.03(16)(16) “Infiltration” means water other than wastewater that enters a sewerage system (including sewer service connections) from the ground through such sources as defective pipes, pipe joints, connections, or manholes. Infiltration does not include, and is distinguished from, inflow.

NR 110.03(17)(17) “Inflow” means water other than wastewater that enters a sewerage system (including sewer service connections) from sources such as roof leaders, cellar drains, yard drains, area drains, foundation drains, sump pumps, drains from springs and swampy areas, manhole covers, cross connections between storm sewers and sanitary sewers, catch basins, cooling towers, storm waters, surface runoff, street wash waters, or drainage. Inflow does not include, and is distinguished from, infiltration.

NR 110.03(19)(19) “Lagoon” means those sewage treatment facilities where the wastewater or sludge containment structure is constructed primarily of earthen materials.