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) (6) Compliance provisions.

NR 440.75(6)(a) (a) Except as provided in sub. (3) (b) 2. a. 2), the following specified methods shall be used to determine whether the gas collection system is in compliance with sub. (3) (b) 2. b.:

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:

NR 440.75(6)(a)1.a. a. For sites with unknown year-to-year solid waste acceptance rate:

)

e

R(e

2L

Q

-kt

-kc

o

m

-

=

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

t is the age of the landfill at equipment installation plus the time the owner or operator intends to use the gas mover equipment or active life of the landfill, whichever is less. If the equipment is installed after closure, t is the age of the landfill at installation in years.

C is the time since closure in years. For an active landfill c = 0 and e-kc = 1.

NR 440.75(6)(a)1.b. b. For sites with known year-to-year solid waste acceptance rate:

å

=

=

where:

Qm is the maximum expected gas generation flow rate in cubic meters per year

k is the methane generation rate constant in year-1

Lo is the methane generation potential in cubic meters per megagram of solid waste

Mi is the mass of solid waste in the ith section in megagrams

ti is the age of the ith section in years

NR 440.75(6)(a)2. 2. If a collection and control system has been installed, actual flow data may be used to project the maximum expected gas generation flow rate instead of, or in conjunction with, the equation in subd. 1. a. or b. If the landfill is still accepting waste, the actual measured flow data will not equal the maximum expected gas generation rate, so calculations using the equation in subd. 1. a. or b. or other methods shall be used to predict the maximum expected gas generation rate over the intended period of use of the gas control system equipment.

NR 440.75(6)(a)3. 3. For the purposes of determining sufficient density of gas collectors for compliance with sub. (3) (b) 2. b. 1) b), the owner or operator shall design a system of vertical wells, horizontal collectors or other collection devices, satisfactory to the department, capable of controlling and extracting gas from all portions of the landfill sufficient to meet all operational and performance standards.

NR 440.75(6)(a)4. 4. For the purpose of demonstrating whether the gas collection system flow rate is sufficient to determine compliance with sub. (3) (b) 2. b. 1) c), the owner or operator shall measure gauge pressure in the gas collection header at each individual well, monthly. If a positive pressure exists, action shall be initiated to correct the exceedance within 5 calendar days, except for the 3 conditions allowed under sub. (4) (a) 2. If negative pressure cannot be achieved without excess air infiltration within 15 calendar days of the first measurement, the gas collection system shall be expanded to correct the exceedance within 120 days of the initial measurement of positive pressure. Any attempted corrective measure may not cause exceedances of other operational or performance standards. An alternative timeline for correcting the exceedance may be submitted to the department for approval.

NR 440.75(6)(a)5. 5. Owners or operators are not required to expand the system as required in subd. 4. during the first 180 days after gas collection system startup.