A. The provisions of
9VAC5-40-30 (Emission testing) or 40 CFR
60.8, whichever is more restrictive, apply.
B.
1. The owner shall calculate the
NMOC emission rate using either the equation provided in subdivision B 1 a of this section or the equation provided in subdivision B 1 b of this section. Both equations may be used if the actual year-to-year
solid waste acceptance rate is known, as specified in subdivision B 1 a of this section, for part of the life of the
landfill and the actual year-to-year
solid waste acceptance rate is unknown, as specified in subdivision B 1 b of this section, for part of the life of the
landfill. The values to be used in both equations are 0.05 per year for k, 170 cubic meters per megagram for L
0, and 4,000 parts per million by volume as hexane for the C
NMOC. For landfills located in geographical areas with a 30-year average annual precipitation of less than 25 inches, as measured at the nearest representative official meteorological site, the k value to be used is 0.02 per year.
a. The following equation shall be used if the actual year-to-year
solid waste acceptance rate is known.
M
NMOC = View
Image2kL0Mi (e-kti) (C
NMOC) (3.6 X 10-9)
where
M
NMOC = Total NMOC emission rate from the landfill, megagrams per year
k = methane generation rate constant, year-1
L0 = methane generation potential, cubic meters per megagram solid waste
Mi = mass of solid waste in the ith section, megagrams
ti = age of the ith section, years
C
NMOC = concentration of NMOC, parts per million by volume as hexane
3.6 X 10-9 = conversion factor
The mass of nondegradable solid waste may be subtracted from the total mass of solid waste in a particular section of the landfill when calculating the value for Mi if documentation of the nature and amounts of such wastes is obtained.
b. The following equation shall be used if the actual year-to-year
solid waste acceptance rate is unknown.
M
NMOC = 2L0 R(e-kc -e-kt)(C
NMOC)(3.6 X 10-9)
where
M
NMOC = mass emission rate of NMOC, megagrams per year
L0 = methane generation potential, cubic meters per megagram solid waste
R = average annual acceptance rate, megagrams per year
k = methane generation rate constant, year-1
t = age of landfill, years
C
NMOC = concentration of NMOC, parts per million by volume as hexane
c = time since closure, years. For active landfill c = 0 and e-kc = 1
3.6 X 10-9 = conversion factor
The mass of nondegradable solid waste may be subtracted from the total mass of solid waste in a particular section of the landfill when calculating the value of R if documentation of the nature and amounts of such waste is maintained.
2. Tier 1. The owner shall compare the calculated
NMOC mass emission rate to the following emission rate applicability criteria:
(i) in the Northern Virginia Volatile Organic Compound Emissions Control Area, 23 megagrams per year or
(ii) in the remaining areas of the Commonwealth, 50 megagrams per year.
a. If the
NMOC emission rate calculated in subdivision B 1 of this section is (i) 23 megagrams per year in the Northern Virginia Volatile Organic Compound Emissions Control Area or (ii) 50 megagrams per year in the remaining areas of the Commonwealth, then the owner shall submit an emission rate report as provided in
9VAC5-40-5880 D 1, and shall recalculate the
NMOC mass emission rate annually as required under
9VAC5-40-5820 C 1.
b. If the calculated
NMOC emission rate is greater than or equal to (i) 23 megagrams per year in the Northern Virginia Volatile Organic Compound Emissions Control Area or (ii) 50 megagrams per year in the remaining areas of the Commonwealth, then the owner shall either comply with
9VAC5-40-5820 C 2, or determine a site-specific
NMOC concentration and recalculate the
NMOC emission rate using the procedures provided in subdivision B 3 of this section.
3. Tier 2. The owner shall determine the
NMOC concentration using the following sampling procedure. The owner shall install at least two sample probes per hectare of
landfill surface that has retained waste for at least two years. If the
landfill is larger than 25 hectares in area, only 50 samples are required. The sample probes should be located to avoid known areas of nondegradable
solid waste. The owner shall collect and analyze one sample of
landfill gas from each probe to determine the
NMOC concentration using Reference Method 25C of Appendix A of 40 CFR Part
60 or Reference Method 18 of Appendix A of 40 CFR Part
60. If using Reference Method 18 of Appendix A of 40 CFR Part
60, the minimum list of compounds to be tested shall be those published in the "Compilation of Air Pollutant Emission Factors (AP-42)" (see
9VAC5-20-21). If composite sampling is used, equal volumes shall be taken from each sample probe. If more than the required number of samples are taken, all samples shall be used in the analysis. The owner shall divide the
NMOC concentration from Reference Method 25C of Appendix A of 40 CFR Part
60 by six to convert from C
NMOC as carbon to C
NMOC as hexane.
a. The owner shall recalculate the NMOC mass emission rate using the equations provided in subdivision B 1 a or B 1 b of this section and using the average NMOC concentration from the collected samples instead of the default value in the equation provided in subdivision B 1 of this section.
b. If the resulting mass emission rate calculated using the site-specific
NMOC concentration is greater than or equal to (i) 23 megagrams per year in the Northern Virginia Volatile Organic Compound Emissions Control Area or (ii) 50 megagrams per year in the remaining areas of the Commonwealth, then the owner shall either comply with
9VAC5-40-5820 C 2, or determine the site-specific methane generation rate constant and recalculate the
NMOC emission rate using the site-specific methane generation rate using the procedure specified in subdivision B 4 of this section.
c. If the resulting
NMOC mass emission rate is less than (i) 23 megagrams per year in the Northern Virginia Volatile Organic Compound Emissions Control Area or (ii) 50 megagrams per year in the remaining areas of the Commonwealth, the owner shall submit a periodic estimate of the emission rate report as provided in
9VAC5-40-5880 D 1 and retest the site-specific
NMOC concentration every five years using the methods specified in this section.
4. Tier 3. The site-specific methane generation rate constant shall be determined using the procedures provided in Reference Method 2E of Appendix A of 40 CFR Part
60. The owner shall estimate the
NMOC mass emission rate using equations in subdivision B 1 a or B 1 b of this section and using a site-specific methane generation rate constant k, and the site-specific
NMOC concentration as determined in subdivision B 3 of this section instead of the default values provided in subdivision B 1 of this section. The owner shall compare the resulting
NMOC mass emission rate to the following emission rate applicability criteria:
(i) in the Northern Virginia Volatile Organic Compound Emissions Control Area, 23 megagrams per year or
(ii) in the remaining areas of the Commonwealth, 50 megagrams per year.
a. If the
NMOC mass emission rate as calculated using the site-specific methane generation rate and concentration of
NMOC is greater than or equal to (i) 23 megagrams per year in the Northern Virginia Volatile Organic Compound Emissions Control Area or (ii) 50 megagrams per year in the remaining areas of the Commonwealth, the owner shall comply with
9VAC5-40-5820 C 2.
b. If the
NMOC mass emission rate is less than (i) 23 megagrams per year in the Northern Virginia Volatile Organic Compound Emissions Control Area or (ii) 50 megagrams per year in the remaining areas of the Commonwealth, then the owner shall submit a periodic emission rate report as provided in
9VAC5-40-5880 D 1 and shall recalculate the
NMOC mass emission rate annually, as provided in
9VAC5-40-5880 D 1 using the equations in subdivision B 1 of this section and using the site-specific methane generation rate constant and
NMOC concentration obtained in subdivision B 3 of this section. 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.
5. The owner may use other methods to determine the NMOC concentration or a site-specific k as an alternative method required in subdivisions B 3 and B 4 of this section if the method has been approved by the board.
C. After the installation of a collection and control system in compliance with
9VAC5-40-5850, the owner shall calculate the
NMOC emission rate for purposes of determining when the system can be removed as provided in
9VAC5-40-5820 C 2 e, using the following equation:
M
NMOC = 1.89 X 10-3 QLFG C
NMOC
where
M
NMOC = mass emission rate of NMOC, megagrams per year
QLFG = flow rate of landfill gas, cubic meters per minute
C
NMOC = NMOC concentration, parts per million by volume as hexane
1. The flow rate of
landfill gas, Q
LFG, 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 § 4 of Reference Method 2E of Appendix A of 40 CFR Part
60.
2. The average
NMOC concentration, C
NMOC, 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 Reference Method 25C or Reference Method 18 of Appendix A of 40 CFR Part
60. If using Reference Method 18 of Appendix A of 40 CFR Part
60, the minimum list of compounds to be tested shall be those published in the "Compilation of Air Pollutant Emission Factors (AP-42)" (see
9VAC5-20-21). The sample location on the common header pipe shall be before any condensate removal or other gas refining units. The owner shall divide the
NMOC concentration from Reference Method 25C of Appendix A of 40 CFR Part
60 by six to convert from C
NMOC as carbon to C
NMOC as hexane.
3. The owner may use an alternative method to determine landfill gas flow rate and NMOC concentration if the method has been approved by the board.
D. When calculating emissions for prevention of significant deterioration purposes, the owner of each
MSW landfill subject to the provisions of this article shall estimate the
NMOC emission rate for comparison to the prevention of significant deterioration major source and significance levels in Article 8 (
9VAC5-80-1700 et seq.) of Part II of 9VAC5 Chapter 80 using the "Compilation of Air Pollutant Emission Factors (AP-42)" (see
9VAC5-20-21) or other measurement procedures acceptable to the board. If a collection system, which complies with the provisions in
9VAC5-40-5820 C 2 is already installed, the owner shall estimate the
NMOC emission rate using the procedures provided in subsection C of this section.
E. For the compliance test required in
9VAC5-40-5820 C 2 c (2), Reference Method 25 or Reference Method 18 of Appendix A of 40 CFR Part
60 shall be used to determine compliance with 98 weight-percent efficiency or the 20 ppmv outlet concentration level, unless an alternative method to demonstrate compliance has been approved by the board as provided by
9VAC5-40-5820 C 2 a (2). If using Reference Method 18 of Appendix A of 40 CFR Part
60, the minimum list of compounds to be tested shall be those published in the "Compilation of Air Pollutant Emission Factors (AP-42)" (see
9VAC5-20-21). The following equation shall be used to calculate efficiency:
Control Efficiency = (NMOCin - NMOCout)/(NMOCin)
where
NMOCin = mass of NMOC entering control device
NMOCout = mass of NMOC exiting control device
Notes
9 Va. Admin. Code §
5-40-5860
Derived from Virginia Register Volume 12, Issue 11, eff. April 1, 1996; amended, Virginia Register Volume 15, Issue 12, eff. April 1, 1999; Volume 20, Issue 8, eff. January 29, 2004.
Statutory Authority
§
10.1-1308 of the Code of Virginia; §§ 110, 111, 123, 129, 171, 172, and 182 of the Clean Air Act; 40 CFR Parts 51 and 60.