Wis. Admin. Code Department of Natural Resources NR 440.50

Current through November 25, 2024
Section NR 440.50 - Stationary gas turbines
(1) APPLICABILITY AND DESIGNATION OF AFFECTED FACILITY.
(a) The provisions of this section are applicable to the following affected facilities: all stationary gas turbines with a heat input at peak load equal to or greater than 10.7 gigajoules (10 million Btu) per hour, based on the lower heating value of the fuel fired.
(b) Any facility under par. (a) which commences construction, modification, or reconstruction after October 3, 1977, is subject to the requirements of this section except as provided in sub. (3) (e) and (j).
(2) DEFINITIONS. As used in this section, terms not defined in this subsection have the meanings given in s. NR 440.02.
(a) "Base load" means the load level at which a gas turbine is normally operated.
(b) "Combined cycle gas turbine" means any stationary gas turbine which recovers heat from the gas turbine exhaust gases to heat water or generate steam.
(bg) "Diffusion flame stationary combustion turbine" means any stationary combustion turbine where fuel and air are injected at the combustor and are mixed only by diffusion prior to ignition. A unit which is capable of operating in both lean premix and diffusion flame modes is considered a lean premix stationary combustion turbine when it is in the lean premix mode, and it is considered a diffusion flame stationary combustion turbine when it is in the diffusion flame mode.
(br) "Duct burner" means a device that combusts fuel and that is placed in the exhaust duct from another source, such as a stationary gas turbine, internal combustion engine or kiln, to allow the firing of additional fuel to heat the exhaust gases before the exhaust gases enter a heat recovery steam generating unit.
(c) "Efficiency" means the gas turbine manufacturer's rated heat rate at peak load in terms of heat input per unit of power output based on the lower heating value of the fuel.
(d) "Electric utility stationary gas turbine" means any stationary gas turbine constructed for the purpose of supplying more than one-third of its potential electric output capacity to any utility power distribution system for sale.
(e) "Emergency fuel" is a fuel fired by a gas turbine only during circumstances, such as natural gas supply curtailment or breakdown of delivery system, that make it impossible to fire natural gas in the gas turbine.
(f) "Emergency gas turbine" means any stationary gas turbine which operates as a mechanical or electrical power source only when the primary power source for a facility has been rendered inoperable by an emergency situation.
(fm) "Excess emissions" means a specified averaging period over which one of the following occurs:
1. The NOx emissions are higher than the applicable emission limit in sub. (3).
2. The total sulfur content of the fuel being combusted in the affected facility exceeds the limit specified in sub. (4).
3. The recorded value of a particular monitored parameter is outside the acceptable range specified in the parameter monitoring plan for the affected unit.
(g) "Fire-fighting turbine" means any stationary gas turbine that is used solely to pump water for extinguishing fires.
(h) "Garrison facility" means any permanent military installation.
(i) "Gas turbine model" means a group of gas turbines having the same nominal air flow, combustor inlet pressure, combustor inlet temperature, firing temperature, turbine inlet temperature and turbine inlet pressure.
(j) "ISO standard day conditions" means 288° Kelvin, 60% relative humidity and 101.3 kilopascals pressure.
(k) "Ice fog" means an atmospheric suspension of highly reflective ice crystals.
(km) "Lean premix stationary combustion turbine" means any stationary combustion turbine where the air and fuel are thoroughly mixed to form a lean mixture for combustion in the combustor. Mixing may occur before or in the combustion chamber. A unit which is capable of operating in both lean premix and diffusion flame modes is considered a lean premix stationary combustion turbine when it is in the lean premix mode, and it is considered a diffusion flame stationary combustion turbine when it is in the diffusion flame mode.
(L) "Natural gas" means a naturally occurring fluid mixture of hydrocarbons, such as methane, ethane, or propane, produced in geological formations beneath the earth's surface that maintains a gaseous state at standard atmospheric temperature and pressure under ordinary conditions. Natural gas contains 20.0 grains or less of total sulfur per 100 standard cubic feet. Equivalents of this in other units are as follows: 0.068 weight percent total sulfur, 680 parts per million by weight (ppmw) total sulfur, and 338 parts per million by volume (ppmv) at 20 degrees Celsius total sulfur. Additionally, natural gas shall either be composed of at least 70% methane by volume or have a gross calorific value between 950 and 1100 Btu per standard cubic foot. Natural gas does not include the following gaseous fuels: landfill gas, digester gas, refinery gas, sour gas, blast furnace gas, coal-derived gas, producer gas, coke oven gas, or any gaseous fuel produced in a process which might result in highly variable sulfur content or heating value.
(m) "Offshore platform gas turbines" means any stationary gas turbine located on a platform in an ocean.
(n) "Peak load" means 100% of the manufacturer's design capacity of the gas turbine at ISO standard day conditions.
(p) "Regenerative cycle gas turbine" means any stationary gas turbine that recovers heat from the gas turbine exhaust gases to preheat the inlet combustion air to the gas turbine.
(q) "Simple cycle gas turbine" means any stationary gas turbine which does not recover heat from the gas turbine exhaust gases to preheat the inlet combustion air to the gas turbine, or which does not recover heat from the gas turbine exhaust gases to heat water or generate steam.
(r) "Stationary gas turbine" means any simple cycle gas turbine, regenerative cycle gas turbine or any gas turbine portion of a combined cycle steam/electric generating system that is not self-propelled. It may, however, be mounted on a vehicle for portability.
(s) "Turbines employed in oil or gas production or oil or gas transportation" means any stationary gas turbine used to provide power to extract crude oil or natural gas, or both, from the earth or to move crude oil or natural gas, or both, or products refined from these substances through pipelines.
(t) "Unit operating day" means a 24-hour period between 12:00 midnight and the following midnight during which any fuel is combusted at any time in the unit. It is not necessary for fuel to be combusted continuously for the entire 24-hour period.
(u) "Unit operating hour" means a clock hour during which any fuel is combusted in the affected unit. If the unit combusts fuel for the entire clock hour, it is considered to be a full unit operating hour. If the unit combusts fuel for only part of the clock hour, it is considered to be a partial unit operating hour.
(3) STANDARD FOR NITROGEN OXIDES.
(a) On and after the date on which the performance test required by s. NR 440.08 is completed, every owner or operator subject to the provisions of this section, as specified in pars. (b), (c) and (d), shall comply with one of the following, except as provided in pars. (e) through (L).
1. No owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere from any stationary gas turbine, any gases which contain nitrogen oxides in excess of:

See PDF for diagram

where:

STD is the allowable ISO corrected, if required as given in sub. (6) (c), NOx emissions (percent by volume at 15% oxygen and on a dry basis)

Y is the manufacturer's rated heat rate at manufacturer's rated load (kilojoules per watt hour), or actual measured heat rate based on lower heating value of fuel as measured at actual peak load for the facility (the value of Y may not exceed 14.4 kilojoules per watt hour)

F is the NOx emission allowance for fuel-bound nitrogen as defined in subd. 4.

2. No owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere from any stationary gas turbine, any gases which contain nitrogen oxides in excess of:

See PDF for diagram

where:

STD is the allowable ISO corrected, if required as given in sub. (6) (c), NOx emissions (percent by volume at 15% oxygen and on a dry basis)

Y is the manufacturer's rated heat rate at manufacturer's rated peak load (kilojoules per watt hour), or actual measured heat rate based on lower heating value of fuel as measured at actual peak load for the facility (the value of Y may not exceed 14.4 kilojoules per watt hour)

F is the NOx emission allowance for fuel-bound nitrogen as defined in subd. 4.

3. The use of F in subds. 1. and 2. is optional. That is, the owner or operator may choose to apply an NOx allowance for fuel-bound nitrogen and determine the appropriate F-value in accordance with subd. 4. or may accept an F-value of zero.
4. If the owner or operator elects to apply an NOx emission allowance for fuel-bound nitrogen, F shall be defined according to the nitrogen content of the fuel during the most recent performance test required under s. NR 440.08 as follows:

Fuel-Bound Nitrogen (percent by weight)F (NOx percent by volume)
1. N<=0.015 0
2. 0.015 < N<=0.1 0.04(N)
3. 0.1< N<=0.25 0.004 + 0.0067(N - 0.1)
4. N>0.25 0.005

where N is the nitrogen content of the fuel (percent by weight), or manufacturers may develop and submit to the department custom fuel-bound nitrogen allowances for each gas turbine model they manufacture. These fuel-bound nitrogen allowances shall be substantiated with data and must be approved for use by the administrator before the initial performance test required by s. NR 440.08.

Note: The administrator will publish notices of approval of custom fuel-bound nitrogen allowances in the federal register.

(b) Electric utility stationary gas turbines with a heat input at peak load greater than 107.2 gigajoules per hour (100 million Btu/hour) based on the lower heating value of the fuel fired except as provided in par. (d) shall comply with the provisions of par. (a) 1.
(c) Stationary gas turbines with a heat input at peak load equal to or greater than 10.7 gigajoules per hour (10 million Btu/hour) but less than or equal to 107.2 gigajoules per hour (100 million Btu/hour) based on the lower heating value of the fuel fired shall comply with the provisions of par. (a) 2.
(d) Electric utility stationary gas turbines with a manufacturer's rated base load at ISO conditions of 30 megawatts or less except as provided in par. (b) shall comply with the provisions of par. (a) 2.
(e) Stationary gas turbines with a heat input at peak load equal to or greater than 10.7 gigajoules per hour (10 million Btu/hour) but less than or equal to 107.2 gigajoules per hour (100 million Btu/hour) based on the lower heating value of the fuel fired and that have commenced construction prior to October 3, 1982 are exempt from par. (a).
(f) Stationary gas turbines using water or steam injection for control of NOx emissions are exempt from par. (a) when ice fog is deemed a traffic hazard by the owner or operator of the gas turbine.
(g) Emergency gas turbines, military gas turbines for use in other than a garrison facility, military gas turbines installed for use as military training facilities and fire fighting gas turbines are exempt from par. (a).
(h) Stationary gas turbines engaged by manufacturers in research and development of equipment for both gas turbine emission control techniques and gas turbine efficiency improvements may be exempted from par. (a) on a case-by-case basis by the department.
(i) Exemptions from the requirements of par. (a) may be granted on a case-by-case basis as determined by the department in specific geographical areas where mandatory water restrictions are required by governmental agencies because of drought conditions. These exemptions may be allowed only while the mandatory water restrictions are in effect.
(j) Stationary gas turbines with a heat input at peak load greater than 107.2 gigajoules per hour that commenced construction, modification or reconstruction between the dates of October 3, 1977, and January 27, 1982, and were required in the September 10, 1979 federal register (44 FR 52792) to comply with 40 CFR 60.332(a) (1), except electric utility stationary gas turbines, are exempt from par. (a).
(k) Stationary gas turbines with a heat input greater than or equal to 10.7 gigajoules per hour (10 million Btu/hour) when fired with natural gas are exempt from par. (a) 2. when being fired with an emergency fuel.
(L) Regenerative cycle gas turbines with a heat input less than or equal to 107.2 gigajoules per hour (100 million Btu/hour) are exempt from par. (a).
(4) STANDARD FOR SULFUR DIOXIDE. On and after the date on which the performance test required to be conducted by s. NR 440.08 is completed, every owner or operator subject to the provisions of this section shall comply with one or the other of the following conditions:
(a) No owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere from any stationary gas turbine any gases which contain sulfur dioxide in excess of 0.015% by volume at 15% oxygen and on a dry basis.
(b) No owner or operator subject to the provisions of this section may burn in any stationary gas turbine any fuel which contains sulfur in excess of 0.8% by weight (8000 ppmw).
(5) MONITORING OF OPERATIONS.
(a) Except as provided in par. (b), the owner or operator of any stationary gas turbine subject to the provisions of this section and using water or steam injection to control NOx emissions shall install, calibrate, maintain and operate a continuous monitoring system to monitor and record the fuel consumption and ratio of water or steam to fuel being fired in the turbine.
(b) The owner or operator of any stationary gas turbine that commenced construction, reconstruction or modification after October 3, 1977, but before July 8, 2004, and which uses water or steam injection to control NOx emissions may, as an alternative to operating the continuous monitoring system described in par. (a), install, certify, maintain, operate and quality-assure a continuous emission monitoring system (CEMS) consisting of NOx and O2 monitors. As an alternative, a CO2 monitor may be used to adjust the measured NOx concentrations to 15% O2 by either converting the CO2 hourly averages to equivalent O2 concentrations using Equation F-14a or F-14b in Appendix F of 40 CFR part 75, incorporated by reference in s. NR 440.17(1), and making the adjustments to 15% O2, or by using the CO2 readings directly to make the adjustments, as described in Method 20. If the option to use a CEMS is chosen, the CEMS shall be installed, certified, maintained and operated as follows:
1. Each CEMS shall be installed and certified according to PS 2 and 3 (for diluent) of 40 CFR part 60, Appendix B, incorporated by reference in s. NR 440.17(1), except the 7-day calibration drift is based on unit operating days, not calendar days. Appendix F, Procedure 1 is not required. The relative accuracy test audit (RATA) of the NOx and diluent monitors may be performed individually or on a combined basis, that is, the relative accuracy tests of the CEMS may be performed in one of the following ways:
a. On a ppm basis (for NOx) and a percent O2 basis for oxygen.
b. On a ppm at 15% O2 basis.
c. On a ppm basis (for NOx) and a percent CO2 basis, for a CO2 monitor that uses the procedures in Method 20 to correct the NOx data to 15% O2.
2. As specified in s. NR 440.13(5) (b), during each full unit operating hour, each monitor shall complete a minimum of one cycle of operation (sampling, analyzing and data recording) for each 15-minute quadrant of the hour, to validate the hour. For partial unit operating hours, at least one valid data point shall be obtained for each quadrant of the hour in which the unit operates. For unit operating hours in which required quality assurance and maintenance activities are performed on the CEMS, a minimum of 2 valid data points, one in each of 2 quadrants, are required to validate the hour.
3. For purposes of identifying excess emissions, CEMS data shall be reduced to hourly averages as specified in s. NR 440.13(8).
a. For each unit operating hour in which a valid hourly average, as described in subd. 2., is obtained for both NOx and diluent, the data acquisition and handling system shall calculate and record the hourly NOx emissions in the units of the applicable NOx emission standard under sub. (3) (a), that is, percent NOx by volume, dry basis, corrected to 15% O2 and International Organization for Standardization (ISO) standard conditions, if required as given in sub. (6) (c) 1. For any hour in which the hourly average O2 concentration exceeds 19.0% O2, a diluent cap value of 19.0% O2 may be used in the emission calculations.
b. A worst case ISO correction factor may be calculated and applied using historical ambient data. For the purpose of this calculation, substitute the maximum humidity of ambient air (Ho), minimum ambient temperature (Ta), and minimum combustor inlet absolute pressure (Po) into the ISO correction equation.
c. If the owner or operator has installed a NOx CEMS to meet the requirements of 40 CFR part 75, and is continuing to meet the ongoing requirements of 40 CFR part 75, the CEMS may be used to meet the requirements of this section, except that the missing data substitution methodology provided for at 40 CFR part 75, subpart D, is not required for purposes of identifying excess emissions. Instead, periods of missing CEMS data are to be reported as monitor downtime in the excess emissions and monitoring performance report required in s. NR 440.07(3).
(c) For any turbine that commenced construction, reconstruction or modification after October 3, 1977, but before July 8, 2004, and which does not use steam or water injection to control NOx emissions, the owner or operator may, for purposes of determining excess emissions, use a CEMS that meets the requirements of par. (b). Also, if the owner or operator has previously submitted and received EPA, department or local permitting authority approval of a petition for an alternative procedure of continuously monitoring compliance with the applicable NOx emission limit under sub. (3), that approved procedure may continue to be used.
(d) The owner or operator of any new turbine constructed after July 8, 2004, and which uses water or steam injection to control NOx emissions may elect to use either the requirements in par. (a) for continuous water or steam to fuel ratio monitoring or may use a NOx CEMS installed, certified, operated, maintained and quality-assured as described in par. (b).
(e) The owner or operator of any new turbine that commences construction after July 8, 2004, and which does not use water or steam injection to control NOx emissions may elect to use a NOx CEMS installed, certified, operated, maintained and quality-assured as described in par. (b). Other acceptable monitoring approaches include periodic testing approved by EPA, the department or local permitting authority or continuous parameter monitoring as described in par. (f).
(f) The owner or operator of a new turbine that commences construction after July 8, 2004, which does not use water or steam injection to control NOx emissions may perform continuous parameter monitoring as follows:
1. For a diffusion flame turbine without add-on selective catalytic reduction controls (SCR), the owner or operator shall define at least 4 parameters indicative of the unit's NOx formation characteristics and shall monitor these parameters continuously.
2. For any lean premix stationary combustion turbine, the owner or operator shall continuously monitor the appropriate parameters to determine whether the unit is operating in low-NOx mode.
3. For any turbine that uses SCR to reduce NOx emissions, the owner or operator shall continuously monitor appropriate parameters to verify the proper operation of the emission controls.
4. For affected units that are also regulated under 40 CFR part 75, if the owner or operator elects to monitor the NOx emission rate using the methodology in Appendix E of 40 CFR part 75, incorporated by reference in s. NR 440.17(1), or the low mass emissions methodology in 40 CFR 75.19, the requirements of this paragraph may be met by performing the parametric monitoring described in sectio n 2.3 of Appendix E of 40 CFR part 75 or in 40 CFR 75.19(c) (1) (iv) (H).
(g) The steam or water to fuel ratio or other parameters that are continuously monitored as described in par. (a), (d) or (f) shall be monitored during the performance test required under s. NR 440.08, to establish acceptable values and ranges. The owner or operator may supplement the performance test data with engineering analyses, design specifications, manufacturer's recommendations and other relevant information to define the acceptable parametric ranges more precisely. The owner or operator shall develop and keep on-site a parameter monitoring plan which explains the procedures used to document proper operation of the NOx emission controls. The plan shall include the parameters monitored and the acceptable ranges of the parameters as well as the basis for designating the parameters and acceptable ranges. Any supplemental data such as engineering analyses, design specifications, manufacturer's recommendations and other relevant information shall be included in the monitoring plan. For affected units that are also subject to 40 CFR part 75 and that use the low mass emissions methodology in 40 CFR 75.19 or the NOx emission measurement methodology in Appendix E of 40 CFR part 75, the owner or operator may meet the requirements of this paragraph by developing and keeping on-site (or at a central location for unmanned facilities) a quality-assurance plan, as described in 40 CFR 75.19(e) (5) or in sectio n 2.3 of Appendix E and sectio n 1.3.6 of Appendix B of 40 CFR part 75, both incorporated by reference in s. NR 440.17(1).
(h) The owner or operator of any stationary gas turbine subject to the provisions of this section:
1. Shall monitor the total sulfur content of the fuel being fired in the turbine, except as provided in subd. 3. The sulfur content of the fuel shall be determined using total sulfur methods described in sub. (6) (d). Alternatively, if the total sulfur content of the gaseous fuel during the most recent performance test was less than 0.4 weight percent (4000 ppmw), ASTM D4084-94, D5504-01, D6228-98, or Gas Processors Association Standard 2377-86, incorporated by reference in s. NR 440.17(2) (a) 52., 64. and 68. and (m). respectively, which measure the major sulfur compounds may be used.
2. Shall monitor the nitrogen content of the fuel combusted in the turbine, if the owner or operator claims an allowance for fuel bound nitrogen, that is, if an F-value greater than zero is being or will be used by the owner or operator to calculate STD in sub. (3). The nitrogen content of the fuel shall be determined using methods described in sub. (6) (c) 9. or an approved alternative.
3. Notwithstanding the provisions of subd. 1., the owner or operator may elect not to monitor the total sulfur content of the gaseous fuel combusted in the turbine, if the gaseous fuel is demonstrated to meet the definition of natural gas in sub. (2) (L), regardless of whether an existing custom schedule approved by the department for this section requires the monitoring. The owner or operator shall use one of the following sources of information to make the required demonstration:
a. The gas quality characteristics in a current, valid purchase contract, tariff sheet or transportation contract for the gaseous fuel, specifying that the maximum total sulfur content of the fuel is 20.0 grains/100 scf or less.
b. Representative fuel sampling data which show that the sulfur content of the gaseous fuel does not exceed 20 grains/100 scf. At a minimum, the amount of fuel sampling data specified in sectio n 2.3.1.4 or 2.3.2.4 of Appendix D to 40 CFR part 75, incorporated by reference in s. NR 440.17(1), is required.
4. For any turbine that commenced construction, reconstruction or modification after October 3, 1977, but before July 8, 2004, and for which a custom fuel monitoring schedule has previously been approved, the owner or operator may, without submitting a special petition to the department, continue monitoring on this schedule.
(i) The frequency of determining the sulfur and nitrogen content of the fuel shall be as follows:
1. 'Fuel oil.' For fuel oil, use one of the total sulfur sampling options and the associated sampling frequency described in sections 2.2.3, 2.2.4.1, 2.2.4.2, and 2.2.4.3 of Appendix D to 40 CFR part 75, incorporated by reference in s. NR 440.17(1), that is, flow proportional sampling, daily sampling, sampling from the unit's storage tank after each addition of fuel to the tank, or sampling each delivery prior to combining it with fuel oil already in the intended storage tank. If an emission allowance is being claimed for fuel-bound nitrogen, the nitrogen content of the oil shall be determined and recorded once per unit operating day.
2. 'Gaseous fuel.' Any applicable nitrogen content value of the gaseous fuel shall be determined and recorded once per unit operating day. For owners and operators that elect not to demonstrate sulfur content using options in par. (h) 3., and for which the fuel is supplied without intermediate bulk storage, the sulfur content value of the gaseous fuel shall be determined and recorded once per unit operating day.
3. 'Custom schedules.' Notwithstanding the requirements of subd. 2., operators or fuel vendors may develop custom schedules for determination of the total sulfur content of gaseous fuels, based on the design and operation of the affected facility and the characteristics of the fuel supply. Except as provided in subd. 3. a. and b., custom schedules shall be substantiated with data and shall be approved by the department before they can be used to comply with the standard in sub. (4).
a. The 2 custom sulfur monitoring schedules set forth in subd. 3 .a. 1) to 4) and in subd. 3. b. are acceptable, without prior department approval:
1) The owner or operator shall obtain daily total sulfur content measurements for 30 consecutive unit operating days, using the applicable methods specified in this section. Based on the results of the 30 daily samples, the required frequency for subsequent monitoring of the fuel's total sulfur content shall be as specified in subd. 3. a. 2), 3) or 4), as applicable.
2) If none of the 30 daily measurements of the fuel's total sulfur content exceeds 0.4 weight percent (4000 ppmw), subsequent sulfur content monitoring may be performed at 12-month intervals. If any of the samples taken at 12-month intervals has a total sulfur content betwee n 0.4 and 0.8 weight percent (4000 and 8000 ppmw), follow the procedures in subd. 3. a. 3). If any measurement exceeds 0.8 weight percent (8000 ppmw), follow the procedures in subd. 3. a. 4).
3) If at least one of the 30 daily measurements of the fuel's total sulfur content is betwee n 0.4 and 0.8 weight percent (4000 and 8000 ppmw), but none exceeds 0.8 weight percent (8000 ppmw), then:
a) Collect and analyze a sample every 30 days for 3 months. If any sulfur content measurement exceeds 0.8 weight percent (8000 ppmw), follow the procedures in subd. 3. a. 4). Otherwise, follow the procedures in subd. 3. a. 3) b).
b) Begin monitoring at 6-month intervals for 12 months. If any sulfur content measurement exceeds 0.8 weight percent (8000 ppmw), follow the procedures in subd. 3. a. 4). Otherwise, follow the procedures in subd. 3. a. 3) c).
c) Begin monitoring at 12-month intervals. If any sulfur content measurement exceeds 0.8 weight percent (8000 ppmw), follow the procedures in subd. 3. a. 4). Otherwise, continue to monitor at this frequency.
4) If a sulfur content measurement exceeds 0.8 weight percent (8000 ppmw), immediately begin daily monitoring according to subd. 3. a. 1). Daily monitoring shall continue until 30 consecutive daily samples, each having a sulfur content no greater than 0.8 weight percent (8000 ppmw), are obtained. At that point, the applicable procedures of subd. 3. a. 2) or 3) shall be followed.
b. The owner or operator may use the data collected from the 720-hour sulfur sampling demonstration described in section 2.3.6 of Appendix D to 40 CFR part 75, incorporated by reference in s. NR 440.17(1), to determine a custom sulfur sampling schedule, as follows:
1) If the maximum fuel sulfur content obtained from the 720 hourly samples does not exceed 20 grains/100 scf, that is, the maximum total sulfur content of natural gas as defined in sub. (2) (L), no additional monitoring of the sulfur content of the gas is required for the purposes of this section.
2) If the maximum fuel sulfur content obtained from any of the 720 hourly samples exceeds 20 grains/100 scf, but none of the sulfur content values, when converted to weight percent sulfur, exceeds 0.4 weight percent (4000 ppmw), then the minimum required sampling frequency shall be one sample at 12-month intervals.
3) If any sample result exceeds 0.4 weight percent sulfur (4000 ppmw), but none exceeds 0.8 weight percent sulfur (8000 ppmw), follow the provisions of subd. 3. a. 3).
4) If the sulfur content of any of the 720 hourly samples exceeds 0.8 weight percent (8000 ppmw), follow the provisions of subd. 3. a. 4).
(j) For each affected unit that elects to continuously monitor parameters or emissions, or to periodically determine the fuel sulfur content or fuel nitrogen content under this section, the owner or operator shall submit reports of excess emissions and monitor downtime, in accordance with s. NR 440.07(3). Excess emissions shall be reported for all periods of unit operation, including startup, shutdown and malfunction. For the purpose of reports required under s. NR 440.07(3), periods of excess emissions and monitor downtime that shall be reported are defined as follows:
1. 'Nitrogen oxides.'
a. For turbines using water or steam to fuel ratio monitoring:
1) An excess emission shall be any unit operating hour for which the average steam or water to fuel ratio, as measured by the continuous monitoring system, falls below the acceptable steam or water to fuel ratio needed to demonstrate compliance with sub. (3), as established during the performance test required in s. NR 440.08. Any unit operating hour in which no water or steam is injected into the turbine shall also be considered an excess emission.
2) A period of monitor downtime shall be any unit operating hour in which water or steam is injected into the turbine, but the essential parametric data needed to determine the steam or water to fuel ratio are unavailable or invalid.
3) Each report shall include the average steam or water to fuel ratio, average fuel consumption, ambient conditions (temperature, pressure and humidity), gas turbine load, and, if applicable, the nitrogen content of the fuel during each excess emission. You do not have to report ambient conditions if you opt to use the worst case ISO correction factor as specified in par. (b) 3. b., or if you are not using the ISO correction equation under the provisions of sub. (6) (c) 1.
b. If the owner or operator elects to take an emission allowance for fuel bound nitrogen, then excess emissions and periods of monitor downtime are as described in subd. 1. b. 1) and 2).
1) An excess emission shall be the period of time during which the fuel-bound nitrogen (N) is greater than the value measured during the performance test required in s. NR 440.08 and used to determine the allowance. The excess emission begins on the date and hour of the sample which shows that N is greater than the performance test value, and ends with the date and hour of a subsequent sample which shows a fuel nitrogen content less than or equal to the performance test value.
2) A period of monitor downtime begins when a required sample is not taken by its due date. A period of monitor downtime also begins on the date and hour that a required sample is taken, if invalid results are obtained. The period of monitor downtime ends on the date and hour of the next valid sample.
c. For turbines using NOx and diluent CEMS:
1) An hour of excess emissions shall be any unit operating hour in which the 4-hour rolling average NOx concentration exceeds the applicable emission limit in sub. (3) (a) 1. or 2. For the purposes of this section, a "4-hour rolling average NOx concentration" is the arithmetic average of the average NOx concentration measured by the CEMS for a given hour (corrected to 15% O2 and, if required under sub. (6) (c) 1., to ISO standard conditions) and the 3 unit operating hour average NOx concentrations immediately preceding that unit operating hour.
2) A period of monitor downtime shall be any unit operating hour in which sufficient data are not obtained to validate the hour, for either NOx concentration or diluent, or both.
3) Each report shall include the ambient conditions (temperature, pressure and humidity) at the time of the excess emission period and, if the owner or operator has claimed an emission allowance for fuel bound nitrogen, the nitrogen content of the fuel during the period of excess emissions. You do not have to report ambient conditions if you opt to use the worst case ISO correction factor as specified in par. (b) 3. b., or if you are not using the ISO correction equation under the provisions of sub. (6) (c) 1.
d. For owners or operator that elect, under par. (f), to monitor combustion parameters or parameters that document proper operation of the NOx emission controls:
1) An excess emission shall be a 4-hour rolling unit operating hour average in which any monitored parameter does not achieve the target value or is outside the acceptable range defined in the parameter monitoring plan for the unit.
2) A period of monitor downtime shall be a unit operating hour in which any of the required parametric data are either not recorded or are invalid.
2. 'Sulfur dioxide.' If the owner or operator is required to monitor the sulfur content of the fuel under par. (h):
a. For samples of gaseous fuel and for oil samples obtained using daily sampling, flow proportional sampling, or sampling from the unit's storage tank, an excess emission occurs each unit operating hour included in the period beginning on the date and hour of any sample for which the sulfur content of the fuel being fired in the gas turbine exceeds 0.8 weight percent and ending on the date and hour that a subsequent sample is taken that demonstrates compliance with the sulfur limit.
b. If the option to sample each delivery of fuel oil has been selected, the owner or operator shall immediately switch to one of the other oil sampling options, that is, daily sampling, flow proportional sampling, or sampling from the unit's storage tank, if the sulfur content of a delivery exceeds 0.8 weight percent. The owner or operator shall continue to use one of the other sampling options until all of the oil from the delivery has been combusted, and shall evaluate excess emissions according to par. (j) 2. a. When all of the fuel from the delivery has been burned, the owner or operator may resume using the as-delivered sampling option.
c. A period of monitor downtime begins when a required sample is not taken by its due date. A period of monitor downtime also begins on the date and hour of a required sample, if invalid results are obtained. The period of monitor downtime shall include only unit operating hours, and ends on the date and hour of the next valid sample.
3. `Ice fog.' Each period during which an exemption provided in sub. (3) (f) is in effect shall be reported in writing to the department quarterly. For each period, the ambient conditions existing during the period, the date and time the air pollution control system was deactivated and the date and time the air pollution control system was reactivated shall be reported. All quarterly reports shall be postmarked by the 30th day following the end of each calendar quarter.
4. `Emergency fuel.' Each period during which an exemption provided in sub. (3) (k) is in effect shall be included in the report required in s. NR 440.07(3). For each period, the type, reasons, and duration of the firing of the emergency fuel shall be reported.
5. All reports required under s. NR 440.07(3) shall be postmarked by the 30th day following the end of each calendar quarter.
(6) TEST METHODS AND PROCEDURES.
(a) The owner or operator shall conduct the performance tests required in s. NR 440.08 using one of the following:
1. EPA Method 20.
2. ASTM D6522-00, incorporated by reference in s. NR 440.17(2) (a) 70.
3. EPA Method 7E and either EPA Method 3 or 3A in 40 CFR part 60 Appendix A, incorporated by reference in s. NR 440.17(1).
(b) The performance tests under par. (a) shall be conducted as follows:
1. Sampling traverse points are to be selected following Method 20 or Method 1 (non-particulate procedures) and sampled for equal time intervals. The sampling shall be performed with a traversing single-hole probe or, if feasible, with a stationary multi-hole probe that samples each of the points sequentially. Alternatively, a multi-hole probe designed and documented to sample equal volumes from each hole may be used to sample simultaneously at the required points.
2. Notwithstanding subd. 1., the owner or operator may test at fewer points than are specified in Method 1 or Method 20 if the following conditions are met:
a. You may perform a stratification test for NOx and diluent pursuant to the procedures specified in section 6.5.6.1(a) to (e) in Appendix A of 40 CFR part 75, incorporated by reference in s. NR 440.17(1).
b. Once the stratification sampling is completed, the owner or operator may use one of the following alternative sample point selection criteria for the performance test:
1) If each of the individual traverse point NOx concentrations, normalized to 15% O2, is within ± 10% of the mean normalized concentration for all traverse points, then you may use 3 points located either 16.7, 50.0 and 83.3 % of the way across the stack or duct, or, for circular stacks or ducts greater than 2.4 meters (7.8 feet) in diameter, at 0.4, 1.2 and 2.0 meters from the wall. The 3 points shall be located along the measurement line that exhibited the highest average normalized NOx concentration during the stratification test.
2) If each of the individual traverse point NOx concentrations, normalized to 15% O2, is within ± 5% of the mean normalized concentration for all traverse points, then you may sample at a single point, located at least one meter from the stack wall or at the stack centroid.
3. Other acceptable alternative reference methods and procedures are given in par. (d).
(c) The owner or operator shall determine compliance with the applicable nitrogen oxides emission limitation in sub. (3) and shall meet the performance test requirements of s. NR 440.08 as follows:
1. For each run of the performance test, the mean nitrogen oxides emission concentration (NOxo) corrected to 15% O2 shall be corrected to ISO standard conditions using the following equation. Notwithstanding this requirement, use of the ISO correction equation is optional for: lean premix stationary combustion turbines; units used in association with heat recovery steam generators (HRSG) equipped with duct burners; and units equipped with add-on emission control devices:

See PDF for diagram

where:

NOx is the emission concentration of NOx at 15% O2 and ISO standard ambient conditions, ppm by volume, dry basis

NOxo is the mean observed NOx concentration, ppm by volume, dry basis, at 15% O2

Pr is the reference combustor inlet absolute pressure at 101.3 kilopascals ambient pressure, mm Hg

Po is the observed combustor inlet absolute pressure at test, mm Hg

Ho is the observed humidity of ambient air, g H2O/g air

e is the transcendental constant,

2.718

Ta is the ambient temperature, K

2. The 3-run performance test required by s. NR 440.08 shall be performed within ± 5% at 30, 50, 75 and 90-to-100% of peak load or at 4 evenly-spaced load points in the normal operating range of the gas turbine, including the minimum point in the operating range and 90-to-100% of peak load, or at the highest achievable load point if 90-to-100% of peak load cannot be physically achieved in practice. If the turbine combusts both oil and gas as primary or backup fuels, separate performance testing is required for each fuel. Notwithstanding these requirements, performance testing is not required for any emergency fuel, as defined in sub. (2) (e).
3. For a combined cycle turbine system with supplemental heat (duct burner), the owner or operator may elect to measure the turbine NOx emissions after the duct burner rather than directly after the turbine. If the owner or operator elects to use this alternative sampling location, the applicable NOx emission limit in sub. (3) for the combustion turbine shall still be met.
4. If water or steam injection is used to control NOx with no additional post-combustion NOx control and the owner or operator chooses to monitor the steam or water to fuel ratio in accordance with sub. (5) (a), then that monitoring system shall be operated concurrently with each EPA Method 20, ASTM D6522-00, incorporated by reference in s. NR 440.17(2) (a) 70., or Method 7E run and shall be used to determine the fuel consumption and the steam or water to fuel ratio necessary to comply with the applicable sub. (3) NOx emission limit.
5. If the owner operator elects to claim an emission allowance for fuel bound nitrogen as described in sub. (3), then concurrently with each reference method run, a representative sample of the fuel used shall be collected and analyzed, following the applicable procedures described in subd. 9. These data shall be used to determine the maximum fuel nitrogen content for which the established water or steam to fuel ratio will be valid.
6. If the owner or operator elects to install a CEMS, the performance evaluation of the CEMS may either be conducted separately, as described in subd. 7., or as part of the initial performance test of the affected unit.
7. If the owner or operator elects to install and certify a NOx CEMS under sub. (5) (e), then the initial performance test required under s. NR 440.08 may be done in the following alternative manner:
a. Perform a minimum of 9 reference method runs, with a minimum time per run of 21 minutes, at a single load level, between 90 and 100% of peak, or the highest physically achievable, load.
b. Use the test data both to demonstrate compliance with the applicable NOx emission limit under sub. (3) and to provide the required reference method data for the RATA of the CEMS described under sub. (5) (b).
c. The requirement to test at 3 additional load levels is waived.
8. If the owner or operator is required under sub. (5) (f) to monitor combustion parameters or parameters indicative of proper operation of NOx emission controls, the appropriate parameters shall be continuously monitored and recorded during each run of the initial performance test, to establish acceptable operating ranges, for purposes of the parameter monitoring plan for the affected unit, as specified in sub. (5) (g).
9. To determine the fuel bound nitrogen content of fuel being fired if an emission allowance is claimed for fuel bound nitrogen, the owner or operator may use equipment and procedures meeting the requirements of the following:
a. For liquid fuels, ASTM D2597-94 (reapproved 1999), D4629-02, D5762-02 or D6366-99, incorporated by reference in s. NR 440.17(2) (a) 33., 60., 66. and 70., respectively.
b. For gaseous fuels, analytical methods and procedures that are accurate to within 5% of the instrument range and are approved by the department.
10. If the owner or operator is required under sub. (5) (i) 1. or 3 to periodically determine the sulfur content of the fuel combusted in the turbine, a minimum of 3 fuel samples shall be collected during the performance test. The samples shall be analyzed for the total sulfur content of the fuel using:
a. For liquid fuels, ASTM D129-00, D1266-98, D1552-01, D2622-98, D4294-02 or D5453-00, incorporated by reference in s. NR 440.17(2) (a) 8., 18., 20., 34., 55. and 64., respectively.
b. For gaseous fuels, ASTM D1072-90 (Reapproved 1994), D3246-96, D4468-85 (Reapproved 2000) or D6667-01, incorporated by reference in s. NR 440.17(2) (a) 15., 44., 59. and 72., respectively. The applicable ranges of some of the ASTM methods are not adequate to measure the levels of sulfur in some fuel gases. Dilution of samples before analysis, with verification of the dilution ratio, may be used, subject to the prior approval of the department.
11. The fuel analyses required under subds. 9. and 10. may be performed by the owner or operator, a service contractor retained by the owner or operator, the fuel vendor, or any other qualified agency.
(d) The owner or operator may use the following as alternatives to the reference methods and procedures specified in this subsection:
1. Instead of using the equation in par. (c) 1., manufacturers may develop ambient condition correction factors to adjust the nitrogen oxides emission level measured by the performance test as provided in s. NR 440.08 to ISO standard day conditions.

Wis. Admin. Code Department of Natural Resources NR 440.50

Cr. Register, January, 1984, No. 337, eff. 2-1-84; am. (3) (d), renum. (6) (b) 2. to be 2. a. and am., cr. (6) (b) 2. b., Register, September, 1986, No. 369, eff. 10-1-86; renum. (1) to be (1) (a), cr. (1) (b), am. (2) (intro.), (3) (a) 3., (6) (a) 1. b. and (b) 2. a., r. (2) (o), Register, September, 1990, No. 417, eff. 10-1-90; r. and recr. (6), Register, July, 1993, No. 451, eff. 7-1-93; am. (3) (a) 3., (j), (5) (c) 3., Register, December, 1995, No. 480, eff. 1-1-96; correction in (6) (f) 1. made under s. 13.93(2m) (b) 7, Stats., Register, November, 1999, No. 527; CR 06-109: am. (1) (a), (2) (p), (3) (a) 1. and 2., (4) (b), (5) (a), (6) (c) (intro.), 1. and 2., cr. (2) (bg), (br), (fm), (km), (L), (t) and (u), (3) (a) 3., (5) (c) to (i) and (j) 5. and (6) (c) 4. to 11., renum. (3) (a) 3. to be (3 (a) 4. and am., r. and recr. (5) (b) and (c) 1. and 2., (6) (a), (b) and (c) 3., renum. (5) (c) (intro.) to be (5) (j) and am., renum. (5) (c) 3. and 4. to be (5) (j) 2. and 4., r. (6) (d) and (e) Register May 2008 No. 629, eff. 6-1-08; corrections in (6) (b) 3. and (c) 10. (intro.) made under s. 13.92(4) (b) 7, Stats., Register May 2008 No. 629.