NR 440.50(5)(h)1.
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.
NR 440.50(5)(h)2.
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.
NR 440.50(5)(h)3.
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:
NR 440.50(5)(h)3.a.
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.
NR 440.50(5)(h)3.b.
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 section 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.
NR 440.50(5)(h)4.
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.
NR 440.50(5)(i)
(i) The frequency of determining the sulfur and nitrogen content of the fuel shall be as follows:
NR 440.50(5)(i)1.
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.
NR 440.50(5)(i)2.
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.
NR 440.50(5)(i)3.
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).
NR 440.50(5)(i)3.a.
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 between 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 between 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.
NR 440.50(5)(i)3.b.
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).
NR 440.50(5)(j)
(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) 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.
NR 440.50(5)(j)1.b.
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.
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 NO
x 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.
NR 440.50(5)(j)1.d.
d. For owners or operator that elect, under
par. (f), to monitor combustion parameters or parameters that document proper operation of the NO
x 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.
NR 440.50(5)(j)2.
2. 'Sulfur dioxide.' If the owner or operator is required to monitor the sulfur content of the fuel under
par. (h):
NR 440.50(5)(j)2.a.
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.
NR 440.50(5)(j)2.b.
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.
NR 440.50(5)(j)2.c.
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.
NR 440.50(5)(j)3.
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.
NR 440.50(5)(j)4.
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.
NR 440.50(6)(a)(a) The owner or operator shall conduct the performance tests required in
s. NR 440.08 using one of the following:
NR 440.50(6)(b)1.
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.
NR 440.50(6)(b)2.
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:
NR 440.50(6)(b)2.b.
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.
NR 440.50(6)(b)3.
3. Other acceptable alternative reference methods and procedures are given in
par. (d).
NR 440.50(6)(c)
(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:
NR 440.50(6)(c)1.
1. For each run of the performance test, the mean nitrogen oxides emission concentration (NO
xo) corrected to 15% O
2 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
NR 440.50(6)(c)2.
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).
NR 440.50(6)(c)3.
3. For a combined cycle turbine system with supplemental heat (duct burner), the owner or operator may elect to measure the turbine NO
x 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 NO
x emission limit in
sub. (3) for the combustion turbine shall still be met.
NR 440.50(6)(c)4.
4. If water or steam injection is used to control NO
x with no additional post-combustion NO
x 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) NO
x emission limit.
NR 440.50(6)(c)5.
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.
NR 440.50(6)(c)6.
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.
NR 440.50(6)(c)7.
7. If the owner or operator elects to install and certify a NO
x CEMS under
sub. (5) (e), then the initial performance test required under
s. NR 440.08 may be done in the following alternative manner:
NR 440.50(6)(c)7.a.
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.
NR 440.50(6)(c)7.b.
b. Use the test data both to demonstrate compliance with the applicable NO
x emission limit under
sub. (3) and to provide the required reference method data for the RATA of the CEMS described under
sub. (5) (b).
NR 440.50(6)(c)8.
8. If the owner or operator is required under
sub. (5) (f) to monitor combustion parameters or parameters indicative of proper operation of NO
x 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).
NR 440.50(6)(c)9.
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:
NR 440.50(6)(c)9.a.
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.
NR 440.50(6)(c)9.b.
b. For gaseous fuels, analytical methods and procedures that are accurate to within 5% of the instrument range and are approved by the department.
NR 440.50(6)(c)10.
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:
NR 440.50(6)(c)10.a.
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.
NR 440.50(6)(c)10.b.
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.
NR 440.50(6)(c)11.
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.
NR 440.50(6)(d)
(d) The owner or operator may use the following as alternatives to the reference methods and procedures specified in this subsection:
NR 440.50(6)(d)1.
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.
NR 440.50 History
History: 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. 7-1-9
3; 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.
