NR 211.11(3)(bm)1.c. c. Provides sufficient information to establish the facility’s actual average daily flow rate for all waste streams, based on data from a continuous effluent flow monitoring device, as well as the facility’s long-term average production rate. Both the actual average daily flow rate and the long-term average production rate shall be representative of current operating conditions;

NR 211.11(3)(bm)1.d. d. Does not have daily flow rates, production levels, or pollutant levels that vary so significantly that equivalent mass limits are not appropriate to control the discharge; and

NR 211.11(3)(bm)1.e. e. Has consistently complied with all applicable categorical pretreatment standards during the period prior to the industrial user’s request for equivalent mass limits.

NR 211.11(3)(bm)2. 2. Upon approval by the control authority an industrial user subject to equivalent mass limits shall:

NR 211.11(3)(bm)2.a. a. Maintain and effectively operate control and treatment technologies adequate to achieve compliance with the equivalent mass limits;

NR 211.11(3)(bm)2.b. b. Continue to record the facility’s flow rates through the use of a continuous effluent flow monitoring device;

NR 211.11(3)(bm)2.c. c. Continue to record the facility’s production rates and notify the control authority whenever production rates are expected to vary by more than 20 percent from its baseline production rates determined in subd. 1. c. Upon notification of a revised production rate, the control authority shall reassess the equivalent mass limit and revise the limit as necessary to reflect changed conditions at the facility; and

NR 211.11(3)(bm)2.d. d. Continue to employ the same or comparable water conservation methods and technologies as those implemented pursuant to subd. 1. a. so long as it discharges under an equivalent mass limit.

NR 211.11(3)(bm)3. 3. A control authority which chooses to establish equivalent mass limits:

NR 211.11(3)(bm)3.a. a. Shall calculate the equivalent mass limit by multiplying the actual average daily flow rate of the regulated processes by the concentration-based daily maximum and monthly average standard for the applicable categorical pretreatment standard and the appropriate unit conversion factor;

NR 211.11(3)(bm)3.b. b. Upon notification of a revised production rate, shall reassess the equivalent mass limit and recalculate the limit as necessary to reflect changed conditions at the facility; and

NR 211.11(3)(bm)3.c. c. May retain the same equivalent mass limit in subsequent control mechanism terms if the industrial user’s actual average daily flow rate was reduced solely as a result of the implementation of water conservation methods and technologies, and the actual average daily flow rates used in the original calculation of the equivalent mass limit were not based on the use of dilution as a substitute for treatment as prohibited by s. NR 211.10 (4). The industrial user shall also be in compliance with s. NR 211.19.

NR 211.11(3)(bm)4. 4. A control authority may not express limits in terms of mass for pollutants such as pH, temperature, radiation, or other pollutants which cannot appropriately be expressed as mass.

NR 211.11(3)(cm) (cm) The control authority may convert the mass limits of the categorical pretreatment standards in chs. NR 233, 235, and 279 to equivalent concentration limits. When converting such limits to concentration limits, the control authority shall use the concentrations listed in the applicable subparts of chs. NR 233, 235, and 279 and document that dilution is not being substituted for treatment as prohibited by s. NR 211.10 (4).

NR 211.11(3)(d) (d) Equivalent limitations calculated in accordance with par. (a), (bm), or (cm) are deemed pretreatment standards for the purposes of this chapter and s. 283.21 (2), Stats. The control authority shall document how the equivalent limits were derived and make this information available to the public. Once incorporated into its control mechanism, the industrial user shall comply with the equivalent limitations in lieu of the promulgated categorical standards from which the equivalent limitations were derived.

NR 211.11(3)(e) (e) When pretreatment standards specify both maximum daily and maximum average limits, the same production or flow figures shall be used in calculating maximum daily and maximum average limits.

NR 211.11(4) (4) Compensation for pollutants in intake water.

NR 211.11(4)(a) (a) Categorical pretreatment standards may be adjusted to reflect the presence of pollutants in an industrial user’s intake water if the applicable categorical pretreatment standards specifically provide that they may be applied on a net basis or if the industrial user demonstrates to the control authority that:

NR 211.11(4)(a)1. 1. The control system used or proposed to meet the categorical pretreatment standards would meet the categorical pretreatment standards in the absence of pollutants in the intake water if the control system is properly installed and operated;

NR 211.11(4)(a)2. 2. The constituents of a generic measure, such as BOD, TSS or oil and grease, in the industrial user’s effluent are substantially similar to the constituents of the generic measure in the intake water. The control authority may waive this requirement if appropriate additional limits are placed on process water pollutants either at the point of discharge or elsewhere; and

NR 211.11(4)(a)3. 3. The intake water is drawn from the same water body as the water body to which the POTW discharges. The control authority may waive this requirement if it finds that no environmental de-gradation will result.

NR 211.11(4)(b) (b) The control authority shall grant credits only to the extent necessary to meet the applicable categorical pretreatment standards, up to a maximum value equal to the influent value. The control authority may require additional monitoring to determine eligibility for credits and compliance with the adjusted standards.

NR 211.11 History History: Cr. Register, July, 1983, No. 331, eff. 8-1-83; am. (1), r. and recr. (2) and (3), cr. (4), Register, March, 1992, No. 435, eff. 4-1-92; CR 13-006: am. (3) (title), cr. (3) (a) 5., r. (3) (b), cr. (3) (bm), r. (3) (c), cr. (3) (cm), (d), (e), am. (4) (a) (intro.) Register January 2014 No. 697, eff. 2-1-14.

NR 211.12 NR 211.12 Combined wastestreams.

NR 211.12(1) (1) Where effluent from a process regulated by a categorical pretreatment standard is mixed prior to treatment with wastewaters other than those generated by the regulated process, fixed alternative discharge limits may be established by the control authority or by the industrial user with the written concurrence of the control authority. These alternative limits shall apply to the mixed effluent. When deriving alternative categorical limits, the control authority or industrial user shall calculate both an alternative daily maximum value using the daily maximum values specified in the appropriate categorical pretreatment standards and an alternative monthly average value using the monthly average values specified in the appropriate categorical pretreatment standards. The industrial user shall comply with the alternative daily maximum and monthly average limits approved by the control authority until the control authority modifies the limits or approves an industrial user modification request. Modification is authorized whenever there is a material or significant change in the values used in the calculation to fix alternative limits for the regulated pollutant. An industrial user shall immediately report any such material or significant change to the control authority. New alternative categorical limits shall be calculated within 30 days.

NR 211.12(2) (2) Alternative limit calculation. Alternative limits shall be derived according to the following formulas:

NR 211.12(2)(a) (a) Alternative concentration limit:

NR 211.12(2)(b) (b) Alternative mass limit:

NR 211.12(2)(c) (c) Where: