NR 428.24(4)(4) Other regulated unit. The owner or operator claiming a regulated emissions unit exemption for an emissions unit under s. NR 428.21 (3), shall maintain a record of all performance tests, calculations, assumptions and methods used to determine the emissions unit’s potential emissions. NR 428.24 HistoryHistory: CR 07-016: cr. Register July 2007 No. 619, eff. 8-1-07; CR 08-103: am. (1) (b) (intro.) Register August 2009 No. 644, eff. 9-1-09; CR 23-017: cr. (1) (c) Register March 2024 No. 819, eff. 4-1-24. NR 428.25NR 428.25 Alternative compliance methods and approaches. NR 428.25(1)(1) Emissions averaging. The owner or operator of an emissions unit may demonstrate compliance with an NOx emission limitation in s. NR 428.22 by participating in an emissions rate averaging program according to the general provisions of par. (a) and either the specifications for facility wide averaging in par. (b) or for multi-facility averaging in par. (c). NR 428.25(1)(a)1.a.a. The participation of an emissions unit in an emissions averaging program shall be designated for each calendar year. Individual emissions units may not be withdrawn from an averaging program during a calendar year, unless each emissions unit in the averaging program meets its applicable emission limit in s. NR 428.22. NR 428.25(1)(a)1.b.b. If an emissions unit at a facility participates in an averaging program, all similar units at the facility shall be included in the averaging program unless the unit is complying with an emission limit in s. NR 428.22 or is participating in another emissions averaging program under this subsection. Similar units at a facility are those which serve a similar process or purpose and which are described by the same general source category under s. NR 428.22 without regard to fuel type or unit size threshold. NR 428.25(1)(a)1.c.c. An emissions unit for which the department has approved an alternative emission limit or compliance schedule under sub. (3) may not participate in an emissions averaging program under this subsection for the purpose of demonstrating compliance with the approved alternative emission limitation or compliance schedule. NR 428.25(1)(a)2.2. ‘Monitoring requirement.’ The owner or operator of an emissions unit participating in an emissions averaging program shall monitor all necessary NOx emissions, as applicable, according to requirements of s. NR 428.23 (1) (b) 1. or 2. The total heat input and NOx mass emissions shall be monitored and measured according to s. NR 428.23 (1) (b) 5. and compiled according to s. NR 428.23 (2) (d). NR 428.25(1)(a)3.3. ‘New units.’ An emissions unit which begins operation on or after August 1, 2007 may not participate in an emissions averaging program under this subsection. NR 428.25(1)(a)4.4. ‘Emission reductions.’ For purposes of this subsection, only emission reductions which go beyond all state and federal requirements are considered excess emission reductions. NR 428.25(1)(b)(b) Facility averaging. An owner or operator may average emissions from emissions units at one facility by complying with the following procedures for demonstrating compliance on an annual and on an ozone season basis with an aggregate NOx emission limit and mass emissions cap: NR 428.25(1)(b)1.1. ‘Notification.’ The owner or operator shall submit to the department a notification of an NOx emissions averaging program by October 1 of the year prior to the emissions averaging year. The notification shall include the following information: NR 428.25(1)(b)1.d.d. For a participating emissions unit not subject to s. NR 428.22, the average emission rate by fuel type over the unit’s normal operating range determined according to methods of s. NR 428.23 (1) (b) 3. The tested average emission rate may be adjusted based on a heat input weighted average of the emissions unit’s annual percent operation at different load points in the previous calendar year. NR 428.25(1)(b)1.e.e. For averaging programs effective on or after January 1, 2013, for each emissions unit, the annual and ozone season heat input for 2000 to 2005, and the annual and ozone season average of the 3 years of highest annual heat input for 2000 to 2005. NR 428.25(1)(b)1.f.f. For averaging programs effective on or after January 1, 2013, an annual and ozone season NOx mass emissions cap in aggregate for the emissions units in the averaging program. The mass emissions caps shall be the summation of the products for each emissions unit of the emission limitation in subd. 1. c. or the average emission rate in subd. 1. d. and the 3-year average annual or ozone season heat input. The mass emission cap shall be calculated as follows: where:
MC is either the annual mass emissions cap or the ozone season mass emissions cap in tons of NOx for all units participating in the averaging program
Ej is the applicable emission limitation for fuel j submitted in subd. 1. c. or the average emission rate in subd. 1. d.
HIj is either the average annual or ozone season heat input for fuel j, submitted in subd. 1. e., for the 3 years of highest heat input from 2000 to 2005
k is the number of fuels fired by a unit either during the year or during the ozone season
n is the number of units participating in the averaging program
NR 428.25(1)(b)2.2. ‘Implementation.’ The department shall review the proposed averaging program provided in the notification and unless the department, within 30 days of receiving the proposed averaging program, requests additional information or revisions to the program, the owner or operator shall comply with the submitted emissions averaging program. NR 428.25(1)(b)3.3. ‘Compliance demonstration.’ The owner or operator of emissions units participating in the averaging program shall submit a compliance report containing the following information by March 1 of the calendar year following the averaging program year: NR 428.25(1)(b)3.a.a. The annual and ozone season actual heat input by fuel type for each emissions unit in the averaging program. NR 428.25(1)(b)3.b.b. The annual and ozone season actual NOx mass emissions for each emissions unit. NR 428.25(1)(b)3.c.c. The annual and ozone season actual average NOx emission rate for each emissions unit calculated as follows: where:
ERavg is the annual or ozone season average emission rate for each emissions unit
NOx Mass is the total NOx mass emissions for the averaging period
HIj is the heat input for fuel type j for the averaging period
n is the number of fuels fired during the averaging period
NR 428.25(1)(b)3.d.d. The annual and ozone season actual NOx mass emissions and heat input in aggregate for all emissions units. NR 428.25(1)(b)3.e.e. The annual and ozone season actual aggregate NOx emission rate for all emissions units. This emission rate is the summation of the total mass of NOx emissions for all emissions units divided by the total heat input for all emissions units and is calculated as follows: where:
ERaggr is the emission rate in aggregate for all emissions units on an annual or ozone season basis
NOx Massu is the total NOx mass emissions for emissions unit u, for the averaging period
HIu is the total heat input for each emissions unit u, for the averaging period
n is the number of emissions units participating in averaging
NR 428.25(1)(b)3.f.f. The annual and ozone season aggregate emission limitation for all emissions units. These emission limitations are the summation of the product of each unit’s actual heat input and emission limitation by fuel type divided by the summation of the actual heat input for all emissions units. The aggregate emission limitations shall be calculated as follows: where:
ELaggr is the aggregate emission limit for all emissions units on an annual or ozone season basis
HIf is the heat input for fuel f, for unit u
ELf is the emission limit for fuel f, for unit u
HIu is the total heat input for emissions unit u, for the averaging period
n is the number of emissions units participating in averaging
j is the number of fuels for unit u
NR 428.25(1)(b)3.g.g. Compliance on an annual and ozone season basis is demonstrated if the aggregate emission rate required in subd. 3. e. is less than the aggregate emission limit required in subd. 3. f., and the NOx mass emissions required in subd. 3. b. is less than the mass emissions cap required in subd. 1. f. NR 428.25(1)(b)4.4. ‘Heat input conversion.’ For an emissions unit subject to emission limitations expressed in units other than heat input, the emission limitation shall be converted to a heat input basis. All required calculations shall be on a common basis with necessary conversions performed according to the methods in 40 CFR part 60, Appendices A and B, incorporated by reference in s. NR 484.04 (13) and (21). NR 428.25(1)(b)5.5. ‘Mass emissions cap exceedance.’ If the total NOx emissions from the emissions units in the averaging program exceed either the annual or ozone season emissions caps determined in subd. 1. f., the owner or operator shall achieve additional NOx reductions to compensate for the excess emissions within 3 calendar years after the averaging year with the exceedance. NR 428.25(1)(c)(c) Multi-facility average. An owner or operator may average emissions from emissions units at multiple facilities by complying with the following procedures for demonstrating compliance on an annual and ozone season basis with an aggregate NOx emission limitation: NR 428.25(1)(c)1.1. ‘Notification.’ The owner or operator shall submit to the department a notification of an NOx emissions averaging program by October 1 of the year prior to the emissions averaging year. The notification shall include the following information: NR 428.25(1)(c)1.d.d. The projected heat input, capacity utilization, NOx emission rate and total NOx mass emissions for each emissions unit on an annual and ozone season basis. NR 428.25(1)(c)1.e.e. The projected heat input, capacity utilization, NOx emission rate and total NOx mass emissions in aggregate for all emissions units participating in the averaging program. NR 428.25(1)(c)2.2. ‘Implementation.’ The department shall review the proposed averaging program provided in the notification and unless the department, within 30 days of receiving the proposed averaging program, requests additional information or revisions to the program, the owner or operator shall comply with the submitted emissions averaging program. NR 428.25(1)(c)3.a.a. The owner or operator proposing to average emissions units at multiple facilities shall provide public notice 60 days prior to the calendar year of the averaging program in newspapers of general circulation for the areas of the emissions units. NR 428.25(1)(c)3.b.b. The public notice shall describe the proposed averaging program, the participating emissions units and how to obtain a copy of the averaging program information required in subd. 1. NR 428.25(1)(c)3.c.c. In addition to the information required in subd. 1., the averaging program information provided to the public upon request shall indicate whether any of the emissions units identified in the proposed averaging program participated in prior averaging programs under this subsection and whether that participation resulted in a violation of the emission limits. NR 428.25(1)(c)4.4. ‘Compliance demonstration.’ The owner or operator participating in an averaging program shall submit a compliance report containing the following information by March 1 of the calendar year following the averaging program year: NR 428.25(1)(c)4.b.b. The annual and ozone season actual NOx mass emissions for each emissions unit. NR 428.25(1)(c)4.c.c. The annual and ozone season actual average NOx emission rate for each emissions unit calculated using equation 7 in par. (b) 3. c. NR 428.25(1)(c)4.d.d. The annual and ozone season actual NOx mass emissions and heat input in aggregate for all emissions units. NR 428.25(1)(c)4.e.e. The annual and ozone season aggregate NOx emission rate for all emissions units calculated using equation 8 in par. (b) 3. e. NR 428.25(1)(c)4.f.f. The annual and ozone season aggregate emission limitation for all emissions units. These emission limitations are the summation of the product of the each unit’s actual heat input and emission limitation divided by the summed actual heat input for all emissions units less an averaging program environmental benefit factor. The aggregate emission limitations are calculated as follows: where:
ELaggr is the aggregate emission limit in aggregate for all emissions units on an annual or ozone season basis
HIu is the heat input for each emissions unit, u, for the specified period of time
ELu is the emission limit for each emissions unit, u. For emission limitations in units other than heat input, the emission limitations shall be converted to a heat input basis according to par. (b) 4.
EBF is the environmental benefit factor. For averaging programs effective on or after January 1, 2013, the EBF is 10% for the annual emission limit and 10% for the ozone season emission limit. Prior to this date the EBF is 0%.
NR 428.25(1)(c)4.g.g. A demonstration of compliance on an annual and ozone season basis consisting of the aggregate emission rates under subd. 4. e. compared to the aggregate emission limitations calculated in subd. 4. f. NR 428.25(1)(d)1.1. All emissions units participating in an emissions averaging program are considered out of compliance if emissions exceed any of the averaging program emission limitations on either an annual or ozone season basis. NR 428.25(1)(d)2.2. Each emissions unit participating in the averaging program shall be considered in violation for each day of non-compliance until corrective action is taken to achieve compliance. NR 428.25(1)(d)3.3. Except for those periods of time for which the department grants an electric or steam utility reliability waiver under s. NR 428.26 to the emissions units exceeding the applicable aggregate average emission limitation, the department shall require the owners or operators of the emissions units in the program to achieve reductions equivalent to the amount of the exceedance. The additional emission reductions shall be achieved within the subsequent 3 years on an annual or ozone season basis, consistent with the period of the exceedance. NR 428.25(1)(d)4.4. All owners or operators of emissions units considered out of compliance with an averaging program emission limitation are liable for each violation and subject to enforcement and penalty provisions under ss. 285.83 and 285.87, Stats. The owners or operators of the emissions units in the averaging plan shall evaluate the emissions and operating data for any period of non-compliance to determine which units are responsible for the non-compliance event. The information used in this evaluation shall be made available to the department within 30 days of the discovery of a non-compliance event.
