Updated MSW Landfill Emission Factors for RTR Risk Modeling
In order to conduct modeling required for the residual risk and technology review (RTR) of the Municipal Solid Waste (MSW) Landfills National Emission Standards for Hazardous Air Pollutants (NESHAP), the EPA has developed MSW landfill emission factors specifically for the RTR. These factors are based on the data originally used in the 2008 Draft AP-42 for this source category in addition to the data submitted in response to the 2008 Draft AP-42. Overall, including the original data and additional data submissions, test reports were available for landfills in 37 different states. All non-detect data was removed then to remove outliers, data that was two standard deviations above or below the mean of each HAP was removed. Each HAP’s data was then averaged to develop the emission factor.
Municipal Solid Waste Landfill Emission Factors for the Residual Risk and Technology Review of Subpart AAAA (Corrected for Air Infiltration)
| Compound | CAS Number | Number of Test Reports | Mean (ppm) |
|---|---|---|---|
| 1,1,2,2-Tetrachloroethane | 79345 | 17 | 3.65E-01 |
| 1,1,2-Trichloroethane | 79005 | 4 | 1.19E-01 |
| 1,2,4-Trichlorobenzene | 120821 | 8 | 3.02E-02 |
| 1,3-Butadiene | 106990 | 6 | 1.77E-01 |
| 1,3-Dichloropropene | 542756 | 10 | 5.73E-03 |
| 1,4-Dichlorobenzene | 106467 | 116 | 9.30E-01 |
| 2,2,4-Trimethylpentane | 540841 | 11 | 7.03E-01 |
| Acetaldehyde | 75070 | 5 | 7.74E-02 |
| Acetonitrile | 75058 | 16 | 3.85E-01 |
| Acrylonitrile | 107131 | 2 | 6.29E-02 |
| Allyl Chloride | 107051 | 1 | 4.08E-03 |
| Benzene | 71432 | 131 | 1.70E+00 |
| Benzyl Chloride | 100447 | 4 | 1.16E-02 |
| Bromoform | 75252 | 5 | 1.02E-02 |
| Carbon Disulfide | 75150 | 88 | 1.72E-01 |
| Carbon Tetrachloride | 56235 | 6 | 1.28E-02 |
| Carbonyl Sulfide | 463581 | 86 | 2.31E-01 |
| Chlorobenzene | 108907 | 93 | 1.82E-01 |
| Chloroform | 67663 | 18 | 3.27E-01 |
| Cumene | 98828 | 7 | 4.51E-01 |
| Ethyl Benzene | 100414 | 55 | 4.12E+00 |
| Ethyl Chloride | 75003 | 33 | 1.66E+00 |
| Ethylene Dibromide | 106934 | 4 | 8.20E-03 |
| Ethylene Dichloride | 107062 | 77 | 2.09E-01 |
| Ethylidene Dichloride (1,1-Dichloroethane) | 75343 | 99 | 1.11E+00 |
| Formaldehyde | 50000 | 5 | 1.17E-02 |
| Hexachlorobutadiene | 87683 | 3 | 4.71E-03 |
| Hexane | 110543 | 48 | 1.64E+01 |
| Methanol | 67561 | 6 | 1.64E+01 |
| Methyl Bromide | 74839 | 7 | 1.28E-02 |
| Methyl Chloride | 74873 | 15 | 1.46E-01 |
| Methyl Chloroform | 71556 | 62 | 1.69E-01 |
| Methyl Isobutyl Ketone | 108101 | 27 | 9.22E-01 |
| Methyl Tert-Butyl Ether | 1634044 | 14 | 6.68E-01 |
| Methylene Chloride | 75092 | 121 | 5.05E+00 |
| m-Xylene | 108383 | 19 | 1.47E+01 |
| Naphthalene | 91203 | 4 | 1.07E-01 |
| o-Xylene | 95476 | 110 | 3.14E+00 |
| p-Dioxane | 123911 | 2 | 5.73E-02 |
| Propylene Dichloride | 78875 | 7 | 5.70E-03 |
| Styrene | 100425 | 31 | 4.23E-01 |
| Tetrachloroethylene | 127184 | 88 | 1.42E+00 |
| Toluene | 108883 | 134 | 2.61E+01 |
| Trichloroethylene | 79016 | 128 | 7.71E-01 |
| Vinyl Acetate | 108054 | 7 | 8.08E-02 |
| Vinyl Bromide | 593602 | 1 | 3.06E-03 |
| Vinyl Chloride | 75014 | 124 | 1.21E+00 |
| Vinylidene Chloride | 75354 | 67 | 1.08E-01 |
| Xylenes (Mixture of o, m, and p Isomers) | 1330207 | 139 | 1.07E+01 |