Wis. Admin. Code Department of Natural Resources NR 446.185

Current through October 28, 2024
Section NR 446.185 - Compliance alternatives
(1) ALTERNATIVE ANNUAL ALLOWABLE MERCURY EMISSIONS.
(a) Owners and operators of a coal-fired EGU affected by this subchapter may use baseline mercury emissions approved by the department as an alternative to procedures in s. NR 446.18(5) (a) in determining annual allowable mercury emissions.
(b) Baseline mercury emissions shall be determined and used for calculating annual allowable mercury emissions for 5-year periods beginning with the period of 2016 to 2020. Baseline mercury emissions shall be determined every 5 years and used to calculate annual allowable mercury emissions for the subsequent 5-year period.
(c) Baseline mercury emissions for each 5-year period shall be determined using fuel mercury content data measured for the calendar year which is 2 years prior to the first year of the applicable 5-year period. The year designated for measuring fuel mercury content is the baseline determination year.

Note: Baseline emissions are measured for 2013 for determining the annual allowable emissions for compliance years 2015 to 2019, measured for 2018 for determining allowable emissions for compliance years 2020 through 2024, etc.

(d) No later than May 1 of the calendar year after the baseline determination year, the owner or operator of a coal-fired EGU shall submit a report to the department that includes information necessary to determine the baseline mercury emissions for that 5-year period.
(e) In the report required under par. (d), the owners or operators of a coal-fired EGU may request alternative data be used for determining baseline emissions if the data for the specified year is not representative of the EGU's normal operations or maintenance schedule.
(f) Baseline mercury emissions for each EGU shall be determined according to the following procedures:
1. Measure and determine the fuel mercury content according to requirements of s. NR 446.18(3) for all fuels combusted in the EGU for the baseline determination year.
2. Calculate the baseline mercury concentration, on a mmBtu-basis, for the baseline determination year according to Equation 11.

See Image

where:

BMC is the average baseline mercury concentration of fuel, in pounds per mmBtu, contained in the fuels combusted in the EGU during the baseline determination year

Fuel Hgannual is the total mass of mercury contained in the fuel determined in subd. 1.

HIi is the total amount of fuel, in mmBtu, consumed each hour i, during the baseline determination year

h is the total number of hours fuel is consumed during the baseline determination year

3. Calculate the baseline mercury emissions according to Equation 12 as the baseline mercury concentration times the 3-year average of annual fuel consumption, in mmBtu, for the baseline determination year and 2 years prior to the baseline determination year.

See Image

where:

BME is the baseline mercury emissions for the EGU in pounds

BMC is the baseline mercury concentration for the EGU determined in subd. 2., in pounds per mmBtu.

HIi is the amount of fuel, in mmBtu combusted in the EGU for each hour i during each year y

h is the total number of hours fuel is combusted in the EGU during each year

(g) When determining annual allowable mercury emissions for achieving compliance on a unit-by-unit basis, use one of the following equations as applicable:
1. For a percent reduction mercury emission limitation, Equation 13.

See Image

where:

Hgallowable is the mass of mercury emissions allowed for the EGU for the compliance year

BME is the baseline emissions for the EGU as determined in par. (f) 3.

Hg CE is the applicable requirement for percent mercury emission reduction divided by 100.

2. For a mercury output emission limitation, Equation 14.

See Image

where:

Hgallowable is the mass of mercury emissions allowed for the compliance year

GEOGWh is the annual gross energy output of the EGU, in GWh, as determined in s. NR 446.18(4) for the compliance year

BMC is the baseline mercury concentration determined in par. (f) 2. for the EGU in pounds per mmBtu

Hg CE is the applicable requirement for percent mercury control removal divided by 100

HIi is the amount of fuel, in mmBtu combusted each hour i, in the baseline determination year

h is the total number of hours fuel is combusted during the calendar year designated for measuring baseline emissions data under par. (c)

EGWh is the annual gross electric output, in GWh, for the baseline determination year calculated according to s. NR 446.18(4) (a)

(2) ALTERNATIVE SO2 COMPLIANCE DETERMINATION.
(a) The owner or operator of a coal-fired EGU may demonstrate compliance with the SO2 emission limitation in s. NR 446.14(1) by demonstrating a minimum SO2 control efficiency equal to or greater than 90% removal of sulfur from fuels combusted in the EGU each year, excluding startup and shutdown, using a method approved by the department.
(b) If electing to demonstrate compliance according to par. (a), the owners or operators of a coal-fired EGU shall submit an SO2 compliance demonstration procedure for department approval no later than October 1, 2013. The compliance procedure shall include test methods to determine sulfur removal from fuel and operating and parametric monitoring procedures to ensure continuous operation of control equipment consistent with maintaining the required control efficiency.
(3) ALTERNATIVE METHODS AND PROCEDURES. The owner or operator of a coal-fired EGU may use methods and procedures in determining annual allowable emissions as approved by the department to account for any of the following:
(a) The contribution to mercury emissions by non-fuel materials inherent to pollution control processes. The contribution to the annual allowable emissions may not exceed the amount calculated when substituting annual mercury content of non-fuel materials for annual fuel mercury content in Equation 7 in s. NR 446.18(5) (a) 1.
(b) When monitoring or implementing control equipment for a stack serving multiple EGUs.

Wis. Admin. Code Department of Natural Resources NR 446.185

CR 07-036: cr. Register November 2008 No. 635, eff. 12-1-08; correction in (3) made under s. 13.92(4) (b) 1, Stats., Register November 2008 No. 635; CR 13-089: am. (1) (b) Register July 2014 No. 703, eff. 8-1-14.