NR 440.75(5)(a)4.a.a. If the NMOC mass emission rate as calculated using the site-specific methane generation rate constant and concentration of NMOC is equal to or greater than 50 megagrams per year, the owner or operator shall comply with sub. (3) (b) 2. NR 440.75(5)(a)4.b.b. If the NMOC mass emission rate is less than 50 megagrams per year, the owner or operator shall submit a periodic emission rate report as provided in sub. (8) (b) 1. and shall recalculate the NMOC mass emission rate annually, as provided in sub. (8) (b) 1. using the equations in subd. 1. and using the site-specific methane generation rate constant and NMOC concentration obtained in subd. 3. The calculation of the methane generation rate constant is performed only once, and the value obtained from this test shall be used in all subsequent annual NMOC emission rate calculations. NR 440.75(5)(a)5.5. ‘Alternative methods.’ The owner or operator may use other methods to determine the NMOC concentration or a site-specific k as an alternative to the methods required in subds. 3. and 4. if the method has been approved by the administrator. NR 440.75(5)(b)1.1. After the installation of a collection and control system in compliance with sub. (6), the owner or operator shall calculate the NMOC emission rate for purposes of determining when the system can be removed as provided in sub. (3) (b) 3., using the following equation: where:
MNMOC is the mass emission rate of NMOC in megagrams per year
QLFG is the flow rate of landfill gas in cubic meters per minute
CNMOC is the NMOC concentration in parts per million by volume as hexane
NR 440.75(5)(b)2.2. The flow rate of landfill gas, QLFG, shall be determined by measuring the total landfill gas flow rate at the common header pipe that leads to the control device using a gas flow measuring device calibrated according to the provisions of section 4 of Method 2E in 40 CFR part 60, Appendix A, incorporated by reference in s. NR 440.17 (1). NR 440.75(5)(b)3.3. The average NMOC concentration, CNMOC, shall be determined by collecting and analyzing landfill gas sampled from the common header pipe before the gas moving or condensate removal equipment using the procedures in Method 25C or Method 18 in 40 CFR part 60, Appendix A, incorporated by reference in s. NR 440.17 (1). If using Method 18, the minimum list of compounds to be tested shall be those published in the most recent Compilation of Air Pollutant Emission Factors, AP-42, incorporated by reference in s. NR 440.17 (2) (i) 2. The sample location on the common header pipe shall be before any condensate removal or other gas refining units. The landfill owner or operator shall divide the NMOC concentration from Method 25C by 6 to convert from CNMOC as carbon to CNMOC as hexane. NR 440.75(5)(b)4.4. The owner or operator may use another method to determine landfill gas flow rate and NMOC concentration if the method has been approved by the department. NR 440.75(5)(c)(c) When calculating emissions for purposes of prevention of significant deterioration, the owner or operator of each MSW landfill subject to the provisions of this section shall estimate the NMOC emission rate for comparison to the major source and significance levels in s. NR 405.02 using the Compilation of Air Pollutant Emission Factors, AP-42, incorporated by reference in s. NR 440.17 (2) (i) 2., or other measurement procedures approved by the department. NR 440.75(5)(d)(d) For the performance test required in sub. (3) (b) 2. c. 2), Method 18, 25 or 25C in 40 CFR part 60, Appendix A, incorporated by reference in s. NR 440.17 (1), shall be used to determine compliance with the 98% by weight reduction efficiency or the 20 ppmv outlet concentration level, unless another method to demonstrate compliance has been approved by the department as provided by sub. (3) (b) 2. a. 2). Method 3 or 3A, in 40 CFR part 60, Appendix A, incorporated by reference in s. NR 440.17 (1), shall be used to determine oxygen for correcting the NMOC concentration as hexane to 3%. In cases where the outlet concentration is less than 50 ppm NMOC as carbon (8 ppm NMOC as hexane), Method 25A shall be used in place of Method 25. If Method 18 is used, the minimum list of compounds to be tested shall be those published in the Compilation of Air Pollutant Emission Factors, AP-42, incorporated by reference in s. NR 440.17 (2) (i) 2. The following equation shall be used to calculate efficiency: where:
NMOCin is the mass of NMOC entering control device
NMOCout is the mass of NMOC exiting control device
NR 440.75(6)(a)1.1. For the purpose of calculating the maximum expected gas generation flow rate from the landfill to determine compliance with sub. (3) (b) 2. b. 1) a), one of the equations in this subdivision shall be used. The k and Lo kinetic factors shall be those published in the Compilation of Air Pollutant Emission Factors, AP-42, incorporated by reference in s. NR 440.17 (2) (i) 2., or other site specific values demonstrated to be appropriate and approved by the department. If k has been determined as specified in sub. (5) (a) 4., the value of k determined from the test shall be used. A value of no more than 15 years shall be used for the intended use period of the gas mover equipment. The active life of the landfill is the age of the landfill plus the estimated number of years until closure. The equations are as follows: where:
Qm is the maximum expected gas generation flow rate in cubic meters per year
Lo is the methane generation potential in cubic meters per megagram of solid waste
R is the average annual acceptance rate in megagrams per year
k is the methane generation rate constant in year-1