Chapter NR 256

NR 256.03(9) (9) Abbreviations to be used:

NR 256.03(9)(a) (a) “SCF” means standard cubic feet.

NR 256.03(9)(b) (b) “Sm 3” means standard cubic meters.

NR 256.03(9)(c) (c) “TTO” and “total toxic organics” mean the sum of the mass of each of the toxic organic compounds specified in the tables within this chapter which are found at a concentration greater than 0.010 mg/l.

NR 256.03 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.04 NR 256.04  Monitoring and reporting requirements.

NR 256.04(1) (1)  Total toxic organics. An indirect discharger may elect to monitor for oil and grease as an alternate to TTO under PSES and PSNS regulatory values. Due to the high solubility of toxic organics in oil and grease, compliance with the oil and grease standard is considered equivalent to compliance with the TTO standard.

NR 256.04(2) (2) Noncontinuous dischargers.

NR 256.04(2)(a) (a) For noncontinuous direct dischargers, the department shall apply effluent limitations or standards in the form of mass-based annual average, concentration-based maximum day and concentration-based maximum monthly average as indicated in the tables within this chapter.

NR 256.04(2)(b) (b) For noncontinuous indirect dischargers, the control authority may elect to establish concentration-based standards as outlined in sub. (3).

NR 256.04(3) (3) Conversion to concentration-based units.

NR 256.04(3)(a) (a) The control authority may apply concentration-based standards which are exactly equivalent to PSNS and PSES mass-based standards. Concentration-based standards shall be derived by the following procedure:

NR 256.04(3)(b) (b) Multiply PSNS or PSES mass-based standards by a) average production (kkg of metal poured), b) raw material usage (kkg of sand reclaimed), or c) air scrubber flow (Sm3 of air scrubbed), whichever applies, and divide by average discharge flow to the POTW. In calculating, use appropriate measurements and conversion factors to ensure that concentration-based units in mg/l result.

NR 256.04(4) (4) Monthly discharge limit. Compliance with the monthly discharge limits, as calculated from monthly average regulatory values from tables contained in this chapter, is required regardless of the number of samples analyzed and averaged.

NR 256.04 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.05 NR 256.05  Compliance dates.

NR 256.05(1) (1) Any existing source subject to this chapter which discharges to waters of the state shall achieve:

NR 256.05(1)(a) (a) The effluent limitations representing BPT by July 1, 1977; and

NR 256.05(1)(b) (b) The effluent limitations representing BAT by July 1, 1984.

NR 256.05(2) (2) Any new source subject to this chapter which discharges to waters of the state shall achieve NSPS at the commencement of discharge.

NR 256.05(3) (3) Any existing source subject to this chapter which introduces process wastewater pollutants into a POTW shall achieve PSES by October 31, 1988.

NR 256.05(4) (4) Any new source subject to this chapter which introduces process wastewater pollutants into a POTW shall achieve PSNS at the commencement of discharge.

NR 256.05 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

subch. I of ch. NR 256 Subchapter I — Aluminum Casting Subcategory

NR 256.10 NR 256.10  Applicability; description of the aluminum casting subcategory.

NR 256.10(1) (1) This subchapter applies to discharges to waters of the state and to introductions of pollutants into publicly owned treatment works from aluminum casting operations. It applies to a production process if the molten metal contains, on average, greater than 50% by weight of aluminum or if aluminum comprises the greatest percentage of the metal, measured by weight.

NR 256.10(2) (2) This subchapter does not apply to the casting of ingots, pigs or other cast shapes following primary metal smelting, which is regulated by the nonferrous metals manufacturing point source category under 40 CFR Part 421. This subchapter does not apply to the casting of aluminum performed as an integral part of aluminum forming and conducted on-site at an aluminum forming plant, which is regulated by the aluminum forming point source category under 40 CFR Part 467.

NR 256.10(3) (3) Processing operations following the cooling of castings, except for grinding scrubber operations, may be regulated by the aluminum forming point source category under 40 CFR Part 467, electroplating point source category under ch. NR 260, or metal finishing point source category under ch. NR 261.

NR 256.10 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.12 NR 256.12  Effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available. Except as provided in 40 CFR 125.30 to 125.32, any existing point source subject to this subchapter, including noncontinuous direct dischargers, shall achieve the following BPT effluent limitations. Grinding scrubber operations may not discharge process wastewater pollutants to waters of the state. - See PDF for table - See PDF for table - See PDF for table - See PDF for table - See PDF for table - See PDF for table - See PDF for table - See PDF for table

NR 256.12 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.13 NR 256.13  Effluent limitations representing the degree of effluent reduction attainable by the application of the best available technology economically achievable. Except as provided in 40 CFR 125.30 to 125.32, any existing point source subject to this subchapter, including noncontinuous direct dischargers, shall achieve the copper, lead, zinc, and total phenols effluent limitations contained in s. NR 256.12. Grinding scrubber operations may not discharge process wastewater pollutants to waters of the state.

NR 256.13 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.14 NR 256.14  New source performance standards. Any new source subject to this subchapter, including noncontinuous direct dischargers, shall achieve the effluent limitations contained in s. NR 256.12. Grinding scrubber operations may not discharge process wastewater pollutants to waters of the state.

NR 256.14 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.15 NR 256.15  Pretreatment standards for existing sources. Except as provided in ss. NR 211.13 and 211.14, any existing source subject to this subchapter which introduces pollutants into a publicly owned treatment works shall comply with ch. NR 211 and achieve the following pretreatment standards for existing sources. Grinding scrubber operations may not discharge process wastewater pollutants to a POTW. - See PDF for table - See PDF for table - See PDF for table - See PDF for table - See PDF for table - See PDF for table - See PDF for table

NR 256.15 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.16 NR 256.16  Pretreatment standards for new sources. Except as provided in s. NR 211.13, any new source subject to this subchapter which introduces pollutants into publicly owned treatment works shall comply with ch. NR 211 and achieve the pretreatment standards contained in s. NR 256.15. Grinding scrubber operations may not discharge process wastewater pollutants to a POTW.

NR 256.16 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

subch. II of ch. NR 256 Subchapter II — Copper Casting Subcategory

NR 256.20 NR 256.20  Applicability; description of the copper casting subcategory.

NR 256.20(1) (1) This subchapter applies to discharges to waters of the state and to introductions of pollutants into publicly owned treatment works from copper casting operations. It applies to a production process if the molten metal contains, on average, greater than 50% by weight of copper or if copper comprises the greatest percentage of the metal, measured by weight.

NR 256.20(2) (2) This subchapter does not apply to the casting of ingots, pigs or other cast shapes following primary metal smelting, which is regulated by the nonferrous metals manufacturing point source category under 40 CFR Part 421. This subchapter does not apply to the casting of copper alloys containing either beryllium at 0.1% or greater by weight or precious metal at 30% or greater by weight.

NR 256.20(3) (3) Processing operations following the cooling of castings, except for grinding scrubber operations, may be regulated by the electroplating point source category under ch. NR 260 or metal finishing point source category under ch. NR 261.

NR 256.20 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.22 NR 256.22  Effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available. Except as provided in 40 CFR 125.30 to 125.32, any existing point source subject to this subchapter, including noncontinuous direct dischargers, shall achieve the following BPT effluent limitations. Grinding scrubber operations may not discharge process wastewater pollutants to waters of the state. - See PDF for table

NR 256.22 Note (1)   These concentrations shall be multiplied by the ratio of (4.8/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured.
(3)   Within the range of 7.0 to 10.0 to all times. - See PDF for table

NR 256.22 Note (1)   These concentrations shall be multiplied by the ratio of (145/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured.
(3)   Within the range of 7.0 to 10.0 to all times. - See PDF for table

NR 256.22 Note (1)   These concentrations shall be multiplied by the ratio of (0.086/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 SCF of air scrubbed) for a specific plant.
(2)   kg/62.3 million Sm3 (pounds per billion SCF) of air scrubbed.
(3)   Within the range of 7.0 to 10.0 at all times. - See PDF for table

NR 256.22 Note (1)   These concentrations shall be multiplied by the ratio of (1,320/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured.
(3)   Within the range of 7.0 to 10.0 to all times. - See PDF for table

NR 256.22 Note (1)   These concentrations shall be multiplied by the ratio of (0.282/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 SCF of air scrubbed) for a specific plant.
(2)   kg/62.3 million Sm3 (pounds per billion SCF) of air scrubbed.
(3)   Within the range of 7.0 to 10.0 to all times. - See PDF for table

NR 256.22 Note (1)   These concentrations shall be multiplied by the ratio of (61/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured.
(3)   Within the range of 7.0 to 10.0 to all times.

NR 256.22 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.23 NR 256.23 Effluent limitations representing the degree of effluent reduction attainable by the application of the best available technology economically achievable. Except as provided in 40 CFR 125.30 to 125.32, any existing point source subject to this subchapter, including noncontinuous direct dischargers, shall achieve the following BAT effluent limitations. Grinding scrubber operations may not discharge process wastewater pollutants to waters of the state. - See PDF for table

NR 256.23 Note (1)   These concentrations shall be multiplied by the ratio of (4.8/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured. - See PDF for table

NR 256.23 Note (1)   These concentrations shall be multiplied by the ratio of (145/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured. - See PDF for table

NR 256.23 Note (1)   These concentrations shall be multiplied by the ratio of (0.086/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 SCF of air scrubbed) for a specific plant.
(2)   kg/62.3 million Sm3 (pounds per billion SCF) of air scrubbed. - See PDF for table

NR 256.23 Note (1)   These concentrations shall be multiplied by the ratio of (1,320/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured. - See PDF for table

NR 256.23 Note (1)   These concentrations shall be multiplied by the ratio of (0.282/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 SCF of air scrubbed) for a specific plant.
(2)   kg/62.3 million Sm3 (pounds per billion SCF) of air scrubbed. - See PDF for table

NR 256.23 Note (1)   These concentrations shall be multiplied by the ratio of (61/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured.

NR 256.23 History History: Cr. Register, June 1989, No. 402, eff. 7-1-89.

NR 256.24 NR 256.24  New source performance standards. Any new source subject to this subchapter, including noncontinuous direct dischargers, shall achieve the following standards. Grinding scrubber operations may not discharge process wastewater pollutants to waters of the state. - See PDF for table

NR 256.24 Note (1)   These concentrations shall be multiplied by the ratio of (4.8/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured.
(3)   Within the range of 7.0 to 10.0 to all times. - See PDF for table

NR 256.24 Note (1)   These concentrations shall be multiplied by the ratio of (145/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured.
(3)   Within the range of 7.0 to 10.0 to all times. - See PDF for table

NR 256.24 Note (1)   These concentrations shall be multiplied by the ratio of (0.086/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 SCF of air scrubbed) for a specific plant.
(2)   kg/62.3 million Sm3 (pounds per billion SCF) of air scrubbed.
(3)   Within the range of 7.0 to 10.0 to all times. - See PDF for table

NR 256.24 Note (1)   These concentrations shall be multiplied by the ratio of (1,320/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured.
(3)   Within the range of 7.0 to 10.0 to all times. - See PDF for table

NR 256.24 Note (1)   These concentrations shall be multiplied by the ratio of (0.282/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 SCF of air scrubbed) for a specific plant.
(2)   kg/62.3 million Sm3 (pounds per billion SCF) of air scrubbed.
(3)   Within the range of 7.0 to 10.0 to all times. - See PDF for table

NR 256.24 Note (1)   These concentrations shall be multiplied by the ratio of (61/x) where x is the actual normalized process wastewater discharge flow (in gallons per 1,000 pounds of metal poured) for a specific plant.
(2)   kg/1,000 kkg (pounds per million pounds) of metal poured.
(3)   Within the range of 7.0 to 10.0 to all times.

NR 256.24 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.25 NR 256.25 Pretreatment standards for existing sources. Except as provided in ss. NR 211.13 and 211.14, any existing source subject to this subchapter which introduces pollutants into a publicly owned treatment works shall comply with ch. NR 211 and achieve the following pretreatment standards for existing sources. Grinding scrubber operations may not discharge process wastewater pollutants to a POTW. - See PDF for table - See PDF for table - See PDF for table - See PDF for table - See PDF for table - See PDF for table

NR 256.25 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.26 NR 256.26  Pretreatment standards for new sources. Except as provided in s. NR 211.13, any new source subject to this subchapter which introduces pollutants into publicly owned treatment works shall comply with ch. NR 211 and achieve the pretreatment standards contained in s. NR 256.25. Grinding scrubber operations may not discharge process wastewater pollutants to a POTW.

NR 256.26 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

subch. III of ch. NR 256 Subchapter III — Ferrous Casting Subcategory

NR 256.30 NR 256.30  Applicability; description of the ferrous casting subcategory.

NR 256.30(1) (1) This subchapter applies to discharges to waters of the state and to introduction of pollutants into publicly owned treatment works from ferrous casting operations. It applies to a production process if the molten metal contains, on average, greater than 50% by weight of ferrous metal or if ferrous metal comprises the greatest percentage of the metal, measured by weight.

NR 256.30(2) (2) Ancillary scrubber operations, such as fan washes and backwashes, are covered by the mass limitations of the associated discrete wet scrubbing device. Water discharges from aftercooling devices are not regulated as a process wastewater in this subcategory.

NR 256.30(3) (3) Processing operations following the cooling of castings, except for grinding scrubber operations, may be regulated by the electroplating point source category under ch. NR 260, or metal finishing point source category under ch. NR 261.

NR 256.30 History History: Cr. Register, June, 1989, No. 402, eff. 7-1-89.

NR 256.31 NR 256.31  Specialized definitions. The following definitions are applicable to terms used in this chapter:

NR 256.31(1) (1) “Cast iron” means an iron containing carbon in excess of the solubility in the austentite that exists in the alloy at the eutectic temperature, or any iron-carbon alloy that contains 1.2% or more carbon by weight.

NR 256.31(2) (2) “Discrete wet scrubbing device” means a distinct, stand-alone device that removes particulates and fumes from a contaminated gas stream by bringing the gas stream into contact with a scrubber liquor, usually water, and from which there is a wastewater discharge, including but not limited to spray towers and chambers, fixed and variable venturi scrubbers, wet caps, packed bed scrubbers, quenchers and orifice scrubbers. It does not include aftercoolers, ancillary scrubber operations such as fan washes and backwashes, or semi-wet scrubbing devices.

NR 256.31(3) (3) “Ductile iron” means a cast iron treated while molten with a master alloy that contains an element such as magnesium or cerium to induce the formation of free graphite as nodules or spherules, which imparts a measurable degree of ductility to the cast metal.

NR 256.31(4) (4) “Gray iron” means a cast iron that gives a gray fracture due to the presence of flake graphite.

NR 256.31(5) (5) “Malleable iron” which means a cast iron made by a prolonged anneal of white cast iron in which either decarburization or graphitization, or both, eliminate some or all of the cementite, and where graphite is present in the form of temper carbon.

NR 256.31(6) (6) “Multiple ferrous melting furnace scrubber configuration” means a configuration where 2 or more discrete wet scrubbing devices are used in series in a single melting furnace exhaust gas stream.

NR 256.31(7) (7) “Primary metal cast” means the metal that is poured in the greatest quantity at an individual plant.

NR 256.31(8) (8) “Semi-wet scrubbing device” means a device to which water is added and totally evaporates prior to dry air pollution control.

NR 256.31(9) (9) “Steel” means and iron-base alloy containing manganese, carbon at less than 1.2% by weight, and often other alloying elements.