NR 204.03(22)(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). NR 204.03(23)(23) “Food crops” means tobacco and crops grown for human consumption. NR 204.03(24)(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. NR 204.03(25)(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., (Y1●Y2●Y3●.....Yn) to the 1/nth power. NR 204.03(26)(26) “Grit” means the heavy solid materials such as sand, gravel and cinders collected from the headwork of a treatment system. NR 204.03(27)(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. NR 204.03(28)(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. NR 204.03(29)(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). NR 204.03(31)(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. NR 204.03(32)(32) “Injection” means the subsurface placement of liquid sludge to a depth of 4 to 12 inches. NR 204.03(33)(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. NR 204.03(34)(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. NR 204.03(35)(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. NR 204.03(36)(36) “Monthly average” means the arithmetic mean of all measurements taken during the month using analytical methodologies specified in ch. NR 219. NR 204.03(37)(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. NR 204.03(38)(38) “Pathogens” means disease causing organisms. This includes, but is not limited to, certain bacteria, protozoa, viruses and viable helminth ova. NR 204.03(40)(40) “Permeability” means the rate of the movement of liquid through the soil expressed in inches per hour. NR 204.03(41)(41) “Person” means an individual, owner, operator, association, partnership, corporation, municipality, interstate agency, state agency or federal agency. NR 204.03(42)(42) “Person who prepares sludge” means a generator. NR 204.03(43)(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. NR 204.03(44)(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. NR 204.03(45)(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. NR 204.03(46)(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. NR 204.03(47)(47) “Recreation area” means a designated area clearly identified for the purpose of providing an opportunity for recreational activity. NR 204.03(48)(48) “Reclamation site” means drastically disturbed land that is reclaimed using sewage sludge. This includes sites such as strip mines and construction sites. NR 204.03(49)(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. NR 204.03(50)(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.