NR 428.04(4)(c)3. 3. The monthly and yearly total hours for each occurrence when a secondary fuel was burned in accordance with the provisions under sub. (2) (i).

NR 428.04(4)(c)4. 4. Other relevant information as required by the department.

NR 428.04 History History: Cr. Register, January, 2001, No. 541, eff. 2-1-01; CR 02-076: cr. (2) (g) 3. Register November 2002 No. 563, eff. 12-1-02; CR 03-049: am. (2) (g) 1., cr. (2) (g) 4. Register December 2003 No. 576, eff. 1-1-04; CR 07-016: am. (2) (h) 1. and 2. Register July 2007 No. 619, eff. 8-1-07; CR 08-103: am. (1) and (3) (b) Register August 2009 No. 644, eff. 9-1-09; CR 23-017: am. (2) (g) 1. d., cr. (2) (i), (4) (c) Register March 2024 No. 819, eff. 4-1-24.

NR 428.05 NR 428.05 Requirements and performance standards for existing sources.

NR 428.05(1) (1) Applicability. The requirements of this section apply to emissions units described in this section that are located in the county of Kenosha, Manitowoc, Milwaukee, Ozaukee, Racine, Sheboygan, Washington or Waukesha and that were initially constructed on or before February 1, 2001.

NR 428.05(2) (2) NOx emissions optimization.

NR 428.05(2)(a) (a) The requirements of this subsection do not apply to emissions units which are subject to the emission limits of sub. (3).

NR 428.05(2)(b) (b) Except as provided under par. (a), (c), or (f) the following categories of NOx emissions units listed under this subsection shall complete a combustion optimization to minimize NOx emissions in accordance with s. NR 439.096 by December 31, 2002:

NR 428.05(2)(b)1. 1. Solid fuel-fired boilers with a maximum design heat input of 75 million Btu per hour or greater and operated during the 2000 ozone season or a later ozone season with a capacity factor of at least 20%.

NR 428.05(2)(b)2. 2. Natural gas-fired boilers with a maximum design heat input of 75 million Btu per hour or greater and operated during the 2000 ozone season or a later ozone season with a capacity factor of at least 20%.

NR 428.05(2)(b)3. 3. Distillate or residual fuel oil-fired boilers with a maximum design heat input of 75 million Btu per hour or greater and operated during the 2000 ozone season or a later ozone season with a capacity factor of at least 20%.

NR 428.05(2)(b)4. 4. Cement kilns, lime kilns and calciners with a maximum design heat input of 75 million Btu per hour or greater and operated during the 2000 ozone season or a later ozone season with a capacity factor of at least 20%.

NR 428.05(2)(b)5. 5. Reheat furnaces, annealing furnaces and galvanizing furnaces with a maximum design heat input of 75 million Btu per hour or greater and operated during the 2000 ozone season or a later ozone season with a capacity factor of at least 20%.

NR 428.05(2)(b)6. 6. Glass manufacturing furnaces with a maximum design heat input of 75 million Btu per hour or greater and operated during the 2000 ozone season or a later ozone season with a capacity factor of at least 20%.

NR 428.05(2)(c) (c) An emissions unit described in par. (b) which first operates with a capacity factor exceeding 20% in an ozone season after the 2000 ozone season shall complete a combustion optimization by December 31 of the calendar year following that ozone season.

NR 428.05(2)(d) (d) The owner or operator of an NOx emissions unit subject to a combustion optimization requirement under par. (b) shall operate the emissions unit in a manner consistent with the results of the combustion optimization.

NR 428.05(2)(e) (e) The owner or operator of a source subject to the NOx emissions optimization requirements of this subsection shall perform monitoring sufficient to determine compliance with the requirements of this subsection. The monitoring required under this paragraph shall be either continuous monitoring of NOx emissions or periodic monitoring of parameters adequate to ascertain the quality of the combustion and shall conform to the source’s approved combustion optimization plan pursuant to s. NR 439.096.

NR 428.05(2)(f) (f) An emissions unit that is capable of firing secondary fuel is not subject to the requirements under this subsection when utilizing only a secondary fuel if any of the following apply:

NR 428.05(2)(f)1. 1. The emissions unit heat input capacity or maximum design power output while utilizing the secondary fuel is less than the applicability thresholds under this subsection.

NR 428.05(2)(f)2. 2. The emissions unit burns the secondary fuel only during any of the following periods:

NR 428.05(2)(f)2.a. a. Supply interruption or curtailment of primary fuel. The secondary fuel usage under this paragraph may not exceed 500 hours within a 12 consecutive month time period unless the owner or operator obtains a fuel variance under s. NR 436.06.

NR 428.05(2)(f)2.b. b. Periodic testing, maintenance, or operator training of the secondary fuel when the periodic testing, maintenance, or operator training does not exceed a combined total of 48 hours during any calendar year.

NR 428.05(2)(f)3. 3. The secondary fuel constitutes less than 1 percent on an energy equivalent basis of the emissions unit’s fuel consumption within the most recent 12 consecutive month time period.

NR 428.05(3) (3) Performance standards.

NR 428.05(3)(a) (a) Utility boilers. No person may cause, allow or permit nitrogen oxides to be emitted from a boiler owned or operated by a utility as defined in s. NR 409.02 (84) with a maximum design heat input of 500 million Btu per hour or greater in excess of the most stringent of the following limits, as applicable, during the ozone season:

NR 428.05(3)(a)1. 1. 0.33 pound per million Btu of heat input on a 30-day rolling average basis, on or after December 31, 2002.

NR 428.05(3)(a)2. 2. 0.31 pound per million Btu of heat input on a 30-day rolling average basis, on or after December 31, 2003.

NR 428.05(3)(a)3. 3. 0.30 pound per million Btu of heat input on a 30-day rolling average basis, on or after December 31, 2004.

NR 428.05(3)(a)4. 4. 0.29 pound per million Btu of heat input on a 30-day rolling average basis, on or after December 31, 2005.