'Jr.iteti States Office of Air Quality EPA-450/4-84-028 Environmentai p:c;sc:;on Planning ?nd Standards December 1984 Agency Research Triangle Park NC 2771 I SEFPk National Air Pollutant Emission Estimates, 1940-1983 -¦i r'« '.Zr--fr.*"-'t.'Crv• w i*«-i mwaaffl ------- EPA-450/4-84-028 National Air Pollutant Emission Estimates, 1940-1983 Monitoring and Data Analysis Division U.S. ENVIRONMENTAL PROTECTION AGENCY Office of Air and Radiation Office of Air Quality Planning and Standards Research Triangle Park, North Carolina 27711 December 1 984 ------- This report is published by the U.S. Environmental Protection Agency to report information of general interest in the field of air pollution. Copies are available free of charge to Federal employees, current contractors and grantees, and nonprofit organizations - as supplies permit - from the Library Services Office (MD-35), U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711; or, for a fee, from the National Technical Information Services, 5285 Port Royal Road, Springfield, Virginia 22161. Publication No. EPA-450/4-84-028 ii ------- ABSTRACT This report presents estimates of trends in nationwide air pollutant emissions for the six major pollutants: particulates, sulfur oxides, nitrogen oxides, volatile organic compounds, carbon monoxide and lead. Estimates are presented for each year from 1940 through 1983. Emission estimates are broken down according to major classifications of air pollution sources. A short analysis of trends is given, along with a discussion of methods used to develop the data. ------- CONTENTS Section Page LIST OF TABLES vi i 1. SUMMARY 1 2. NATIONWIDE EMISSION TRENDS, 1940-1983 3 2.1 Particulates 3 2.2 Sulfur Oxi des 3 2.3 Nitrogen Oxides 4 2.4 Volatile Organic Compounds. ............ 4 2.5 Carbon Monoxide 4 2.6 Lead 5 3. METHODS 33 3.1 Transportation 34 3.1.1 Motor Vehicles 34 3.1.2 Aircraft 35 3.1.3 Railroads 35 3.1.4 Vessels 35 3.1.5 Nonhi ghway Use of Motor Fuels 35 3.2 Fuel Combustion in Stationary Sources 35 3.2.1 Coal 35 3.2.2 Fuel Oil 36 3.2.3 Natural Gas 36 3.2.4 Other Fuels 36 3.3 Industrial Processes 36 3.3.1 Miscellaneous Industrial Processes 37 3.4 Solid Waste Disposal 37 3.5 Miscellaneous Sources 37 3.5.1 Forest Fi res 37 3.5.2 Agricultural Burning 38 3.5.3 Coal Refuse Burning 38 3.5.4 Structural Fires . 38 3.5.5 Nonindustrial Organic Solvent Use 38 v ------- CONTENTS (continued) Page 4. ANALYSIS OF TRENDS 39 4.1 Particulates 40 4.2 Sulfur Oxides 42 4.3 Nitrogen Oxides 43 4.4 Volatile Organic Compounds 44 4.5 Carbon Monoxide 45 4.6 Lead 46 5. REFERENCES 49 TECHNICAL REPORT DATA AND ABSTRACT 53 ------- LIST OF TABLES Table Page 1. Summary of National Emission Estimates 2 2. Summary of Estimated Particulate Emissions, 1940-1970 6 3. Summary of Estimated Sulfur Oxide Emissions, 1940-1970 7 4. Summary of Estimated Nitrogen Oxide Emissions, 1940-1970. ... 8 5. Summary of Estimated Volatile Organic Compound Emissions, 1940-1970 9 6. Summary of Estimated Carbon Monoxide Emissions, 1940-1970 ... 10 7. National Estimates of Particulate Emissions, 1970-1983 11 8. National Estimates of Sulfur Oxide Emissions, 1970-1983 .... 12 9. National Estimates of Nitrogen Oxide Emissions, 1970-1983 ... 13 10. National Estimates of Volatile Organic Compound Emissions, 1970-1983 14 11. National Estimates of Carbon Monoxide Emissions, 1970-1983. . . 15 12. National Estimates of Lead Emissions, 1970-1983 16 13. Particulate Emissions from Transportation 17 14. Sulfur Oxide Emissions from Transportation 18 15. Nitrogen Oxide Emissions from Transportation 19 16. Volatile Organic Compound Emissions from Transportation .... 20 17. Carbon Monoxide Emissions from Transportation 21 18. Particulate Emissions from Fuel Combustion 22 19. Sulfur Oxide Emissions from Fuel Combustion 23 20. Nitrogen Oxide Emissions from Fuel Combustion 24 21. Volatile Organic Compound Emissions from Fuel Combustion. ... 25 22. Carbon Monoxide Emissions from Fuel Combustion 26 vi i ------- LIST OF TABLES (continued) Table Page 23. Particulate Emissions from Industrial Processes 27 24. Sulfur Oxide Emissions from Industrial Processes 28 25. Nitrogen Oxide Emissions from Industrial Processes 29 26. Volatile Organic Compound Emissions from Industrial Processes 30 27. Carbon Monoxide Emissions from Industrial Processes 31 28. Lead Emissions from Industrial Processes 32 29. Theoretical 1983 National Emission Estimates with 1970 Level of Control 48 vi i i ------- NATIONAL AIR POLLUTANT EMISSION ESTIMATES 1940-1983 1. SUMMARY The primary objectives of this publication are to provide current estimates of nationwide emissions for six major pollutants: particu- late matter (PM), sulfur oxides (SO?), nitrogen oxides (NOv), volatile organic compounds (V0C), carbon monoxide (CO) and lead (Pb). Esti- mates are presented for 1940, 1950, and 1960 to give an historical perspective of national air pollutant emissions, and for 1970 through 1983 as an indication of recent trends. These data entirely replace those published earlier for 1940-1982 in EPA report National Air Pollutant Emission Estimates, 1940-1982 (EPA-450/4-83-024). Because of modifications in methodology and use of more refined emission factors, data from this report should not be compared with data in the earlier report. Reporting of emissions on a nationwide basis, while useful as a general indicator of pollutant levels, has definite limitations. National totals or averages are not the best guide for estimating trends for particular localities. Vet, it is important that some criteria be established for measurement of national progress in the control of air pollutant emissions. The emission estimates presented herein represent calculated estimates based on standard emission in- ventory procedures. Since these data are estimates only and do not represent the results of any program for the measurement of actual emissions, their accuracy is somewhat limited. Similarly, it would not necessarily be expected that these emission estimates would be in agreement with emission estimates derived through a different emission inventory procedure. The principal objective of compiling these data is to identify probable overall changes in emissions on a national scale. It should be recognized that these estimated national trends in emissions may not be representative of local trends in emissions or ai r quali ty. 1 ------- TABLE 1 SUMMARY OF NATIONAL EMISSION ESTIMATES Units of Sulfur Nitrogen Volatile Carbon Measurement Year Particulates Oxides Oxides Organics Monoxide Lead PM, SO? NOXt VOC, CO: Teragrams/Year 1940 22.4 18.0 6.7 17.7 79.4 NA (106 metric tons/year) 1950 24.2 20.3 9.3 20.3 84.8 NA 1960 20.9 20.0 12.8 23.3 87.5 NA Lead (Pb): 1970 18.0 28.2 18.1 27.0 98.3 203. 1971 16.7 26.8 18.5 26.3 96.3 220. Gigagrams/Year 1972 15.0 27.4 19.7 26.3 93.8 231. (103 metric ton/year) 1973 13.9 28.7 20.2 25.7 89.5 202. 1974 12.2 27.0 19.6 24.1 84.6 162. 1975 10.3 25.6 19.1 22.7 80.5 147. 1976 9.6 26.2 20.3 23.8 85.3 153. 1977 9.0 26.3 20.9 23.6 81.1 141. 1978 8.9 24.5 21.0 24.2 80.6 127. 1979 8.8 24.5 21.1 23.5 77.4 108. 1980 8.3 23.2 20.3 22.3 75.0 70. 1981 7.7 22.3 20.5 21.0 72.3 55. 1982 6.8 21.3 19.6 19.4 66.1 54. 1983 6.9 20.8 19.4 19.9 67.6 46. PM, SO?, N0X, VOC, CO: (106 short tons/year) 1940 24.7 19.8 7.4 19.5 87.5 NA 1950 26.7 22.4 10.3 22.4 93.5 NA Lead (Pb): 1960 23.0 22.0 14.1 25.7 96.5 NA 1970 19.8 31.1 20.0 29.8 108.4 224. (103 short ton/year) 1971 18.4 29.5 20.4 29.0 106.2 243. 1972 16.5 30.2 21.7 29.0 103.4 255. 1973 15.3 31.6 22.3 28.3 98.7 223. 1974 13.4 29.8 21.6 26.6 93.3 178. 1975 11.4 28.2 21.1 25.0 88.7 162. 1976 10.6 28.9 22.4 26.2 94.0 168. 1977 9.9 29.0 23.0 26.0 89.4 155. 1978 9.8 27.0 23.1 26.7 88.8 141. 1979 9.7 27.0 23.3 25.9 85.3 119. 1980 9.1 25.6 22.4 24.6 82.7 77. 1981 8.5 24.6 22.6 23.1 79.7 61. 1982 7.5 23.5 21.6 21.4 72.9 60. 1983 7.6 22.9 21.4 21.9 74.5 51. Change 1940-1983 -69% +16% +190% +12% -15% NA Change 1970-1983 -62% -262 +7% -26% -31% -77 Change 1975-1983 -33% -19* +2% -12% -16% -68 2 ------- 2. NATIONWIDE EMISSION TRENDS, 1940-1983 Table 1 gives a summary of total national emission estimates for 1940-1983. Tables 2 through 12 present summaries for each year according to the five major categories of sources: transportation, stationary source fuel combustion, industrial processes, solid waste disposal, and miscellaneous sources. More detailed breakdowns of emissions for 1970 through 1983 are given in Tables 13 through 17 for transportation, Tables 18 through 22 for stationary source fuel combustion, and in Tables 23 through 28 for industrial processes. The Standard Industrial Classifications (SIC) are shown for each process category in the industrial process tables. These designa- tions are not intended to represent the complete emissions for all SIC categories and serve only to identify and classify the industrial process shown. In all tables, data are reported in metric units, either as teragrams (10*2 grams) or gigagrams (10^ grams) per year. One teragram equals approximately 1.1 x 10^ short tons and one gigagram equals approxi- mately 1.1 x 10^ short tons. 2.1 Particulates (PM) Parti cul ate emi ssi ons result primarily from industrial processes and from fuel combustion in stationary sources. For 1940 and 1950, emissions from transportation (coal combustion by railroads) and miscellaneous sources (forest fi res) were also si gni ficant. Emissions from fuel combustion and industrial processes did not change sub- stantially from 1940 to 1970. Since 1970, emissions from these categories have been substantially reduced as the result of installa- tion of air pollution control equipment. Particulate emissions from transportation decreased substantially from 1940 to 1960 as the result of the obsolescence of coal-burning railroad locomotives. From 1960 to 1983, particulates from transportation increased due to increased travel by highway motor vehicles. Miscellaneous source emissions decreased substantially from 1940 to 1970, primarily due to a major reduction in the acreage burned by forest wildfires. Solid waste emissions increased from 1940 to 1970, but declined substantially to 1983 as the result of air pollution regulations prohibiting or limiting the burning of solid waste. 2.2 Sulfur Oxides (SO2) Sulfur oxide emissions occur mostly from stationary source fuel combustion and to some extent, from industrial processes. Sulfur oxide emissions from combustion of coal by railroad locomotives were also significant in 1940 and 1950. Emissions from solid waste dis- posal and miscellaneous sources have always been minor. Emissions from stationary source fuel combustion increased greatly from 1940 to 3 ------- From 1970 to 1983, emissions from fuel combustion have decreased slightly. During this time period, fuel combustion, particularly of sulfur-bearing coal and oil, continued to increase, but the average sulfur contents of fuels decreased and a limited number of pollution control systems (flue gas desulfurization) were installed. Emissions from industrial processes increased from 1940 to 1970 reflecting increased industrial production. From 1970 to 1983, industrial process emissions decreased primarily due to control measures by primary nonferrous smelters and sulfuric acid plants. 2.3 Nitrogen Oxides (N0X) Nitrogen oxide emissions are produced largely by stationary source fuel combustion and transportation sources. Emissions have steadily increased over the period from 1940 to 1970 as the result of increased fuel combustion. From 1970 to 1983, the size of the increase was reduced somewhat by controls installed on highway motor vehicles and to a lesser extent by controls on coal-fired electric utility boilers. Since 1979, N0X emissions have actually decreased slightly. Nitrogen oxide emissions by industrial processes increased from 1940 to 1970, but have remained about constant since then. 2.4 Volatile Organic Compounds (V0C) The largest sources of V0C emissions are transportation sources and industrial processes. Miscellaneous sources, primarily forest wild- fires and non-industrial consumption of organic solvents, also contri- bute significantly to total V0C emissions. Emissions from stationary source fuel combustion and solid waste disposal are relatively small. Transportation source emissions increased greatly from 1940 to 1970, primarily as the result of increased travel by highway motor vehicles. Since 1970, air pollution controls installed on motor vehicles have been effective in reducing V0C emissions. Industrial process emis- sions have increased through the late 70's, generally reflecting increased levels of industrial production. Controls installed on industrial processes since 1970 have had a modest effect in preventing additional increases in V0C emissions. Since 1979, V0C emissions from industrial processes have decreased. This reflects both the installa- tion of controls and a lower level of industrial output during these years. Emissions from stationary source combustion declined from 1940 through the mid-1970's and then increased to 1983, reflecting primarily the trend in residential wood combustion. 2.5 Carbon Monoxide (CO) Transportation sources are the largest emitters of carbon monoxide. Major increases in emissions occurred from 1940 to 1970 as the result of increased motor vehicle travel. From 1970 to 1983, transportation emissions decreased as the result of highway vehicle emission controls, 4 ------- despite continued increases in highway vehicle travel. Emissions from stationary source fuel combustion have declined from 1940 through the mid-1970*s and then increased slightly to 1983. Prior to 1970, residential coal and wood combustion contributed significantly to CO emissions. However, as residential use of coal has been replaced by other fuels, residential emissions have declined. Beginning in the late 1970's, residential combustion of wood has increased, however, and as a result CO emissions from residential fuel combustion increased. Carbon monoxide emissions from industrial processes increased from 1940 to 1950 but have declined somewhat since then. The decline is due largely to the obsolesence of a few high-polluting industrial processes such as carbon black manufacture by the channel process and limited installation of control equipment on other processes. These factors have been significant enough to offset growth in industrial production which would otherwise have caused a net increase in emissions. Carbon monoxide emissions from solid waste disposal increased from 1940 to 1970, but have subse- quently decl i ned as the result of air pollution control efforts. Substantial emissions of carbon monoxide from forest fires occurred in 1940. In later years, these emissions have been much smaller due to improved fire prevention efforts and more effective suppression of wildfi res. 2.6 Lead (Pb) Lead emissions result primarily from transportation sources and industrial processes. Emissions for lead were not computed before 1970 because of missing data, especially for transportation sources. From 1970 to 1974, the transportation emissions varied based on the amount of gasoline consumed and the average lead content. From 1975 to 1983, transportation emissions decreased as a result of the con- version to unleaded gasoline. Emissions from industrial processes have declined from 1970 to 1983 as the result of installation of air pollution control equipment. 5 ------- TABLE 2 1940-1970 SUMMARY OF ESTIMATED EMISSIONS OF PARTICULATES (TERAGRAMS/YEAR) Source Category 1940 1950 1960 1970 Transportation Highway Vehicles 0.2 0.3 0.6 0.9 Ai rcraft 0.0 0.0 0.0 0.1 Rail roads 2.4 1.7 0.1 0.1 Vessels 0.1 0.1 0.0 0.0 Other Off-Highway 0.0 0.0 0.0 0.1 Transportation Total 2.7 2.1 0.7 1.2 Stationary Source Fuel Combustion Electric Utilities 1.3 2.0 2.8 2.3 Industrial 3.3 2.7 1.7 1.6 Commercial Institutional 0.4 0.5 0.1 0.1 Residential 2.1 1.5 0.9 0.5 Fuel Combustion Total 7.1 6.7 5.5 4.5 Industrial Processes Iron and Steel Mills 3.0 3.5 1.7 1.2 Primary Metal Smelting 0.6 0.6 0.5 0.5 Secondary metals 0.3 0.3 0.2 0.2 Mineral Products 1.7 2.6 3.4 2.6 Chemicals 0.3 0.4 0.3 0.2 Petroleum Refining 0.0 0.0 0.1 0.1 Wood Products 0.4 0.7 0.8 0.6 Food and Agriculture 0.8 0.8 0.9 0.8 Mining Operations 1.3 3.4 4.1 3.9 Industrial Processes Total 8.4 12.3 12.0 10.1 Solid Waste Disposal Inci neration 0.3 0.3 0.4 0.4 Open Burning 0.2 0.3 0.5 0.7 Sol id Waste Total 0.5 0.6 0.9 1.1 Miscellaneous Forest Fires 2.9 1.7 1.0 0.7 Other Burning 0.8 0.8 0.8 0.4 Misc. Total 3.7 2.5 1.8 1.1 Total of Al1 Sources 22.4 24.2 20.9 18.0 NOTE: One teragram equals 10*2 grams (10® metric tons) or approximately 1.1 x 10° short tons. A value of zero indicates emissions of less than 50,000 metric tons. 6 ------- TABLE 3 1940-1970 SUMMARY OF ESTIMATED EMISSIONS OF SULFUR OXIDES (TERAGRAMS/YEAR) Source Category 1940 1950 1960 1970 Transportation Highway Vehicles 0.0 0.1 0.1 0.3 Ai reraft 0.0 0.0 0.0 0.0 Rail roads 2.7 2.0 0.2 0.1 Vessels 0.2 0.2 0.1 0.1 Other Off-Highway 0.0 0.0 0.0 0.1 Transportation Total 2.9 2.3 0.4 0.6 Stationary Source Fuel Combustion Electric Utilities 2.2 4.1 8.4 15.8 Industrial 5.5 5.2 3.5 4.1 Commercial Institutional 1.0 1.7 1.0 0.9 Residential 2.3 1.9 1.1 0.5 Fuel Combustion Total 11.0 12.9 14.0 21.3 Industrial Processes Primary Metal Smelting 2.5 2.8 3.0 3.6 Pulp Mills 0.1 0.1 0.1 0.1 Chemi cals 0.2 0.4 0.4 0.6 Petroleum Refining 0.2 0.3 0.6 0.7 Iron & Steel 0.3 0.5 0.4 0.5 Secondary Metals 0.0 0.0 0.0 0.0 Mineral Products 0.3 0.5 0.5 0.6 Natural Gas Processing 0.0 0.0 0.1 0.1 Industrial Processes Total 3.6 4.6 5.1 6.2 Solid Waste Disposal Inci neration 0.0 0.0 0.0 0.0 Open Burning 0.0 0.0 0.0 0.0 Solid Waste Total 0.0 0.0 0.0 0.0 Miscellaneous Forest Fires 0.0 0.0 0.0 0.0 Other Burning 0.5 0.5 0.5 0.1 Misc. Total 0.5 0.5 0.5 0.1 Total of Al1 Sources 18.0 20.3 20.0 28.2 NOTE: One teragram equals 10^ grams (10^ metric tons) or approximately 1.1 x 10® short tons. A value of zero indicates emissions of less than 50,000 metric tons. 7 ------- TABLE 4 1940-1970 SUMMARY OF ESTIMATED EMISSIONS OF NITROGEN OXIDES (TERAGRAMS/YEAR) Source Category 1940 1950 1960 1970 Transportation Highway Vehicles 1.3 2.1 3.6 6.0 Ai reraft 0.0 0.0 0.0 0.1 Rail roads 0.6 0.9 0.7 0.6 Vessels 0.1 0.1 0.1 0.1 Other Off-Highway 0.2 0.4 0.5 0.8 Transportation Total 2.2 3.5 4.9 7.6 Stationary Source Fuel Combustion " Electric Utilities 0.6 1.2 2.3 4.5 Industrial 2.2 2.9 3.7 3.9 Commercial Institutional 0.2 0.3 0.3 0.3 Residential 0.3 0.3 0.4 0.4 Fuel Combustion Total 3.3 4.7 6.7 9.1 Industrial Processes Petroleum Refining 0.1 0.1 0.2 0.2 Chemi cals 0.0 0.0 0.1 0.2 Iron and Steel Mills 0.0 0.1 0.1 0.1 Pulp Mil Is 0.0 0.0 0.0 0.0 Mineral Products 0.1 0.1 0.1 0.2 Industrial Processes Total 0.2 0.3 0.5 0.7 Solid Waste Disposal Inci neration 0.0 0.1 0.1 0.1 Open Burning 0.1 0.1 0.2 0.3 Solid Waste Total 0.1 0.2 0.3 0.4 Mi seel 1aneous Forest Fires 0.7 0.4 0.2 0.2 Other Burning 0.2 0.2 0.2 0.1 Misc. Total 0.9 0.6 0.4 0.3 Total of All Sources 6.7 9.3 12.8 18.1 NOTE: One teragram equals 10^ grams (10& metric tons) or approximately 1.1 x 10° short tons. A value of zero indicates emissions of less than 50,000 metric tons. 8 ------- TABLE 5 1940-1970 SUMMARY OF ESTIMATED EMISSIONS OF VOLATILE ORGANIC COMPOUNDS (TERAGRAMS/YEAR) Source Category Transportation Highway Vehicles Ai rcraft Railroads Vessels Other Off-Highway Transportation Total Stationary Source Fuel Combustion Electric Utilities Industrial Commercial Institutional Residential Fuel Combustion Total Industrial Processes Chemi cals Petroleum Refining Iron and Steel Mills Mineral Products Food and Agriculture Industrial Organic Solvent Use Petroleum Product Production and Marketing Industrial Processes Total Sol id Waste Disposal Inci neration Open Burning Solid Waste Total Miscellaneous Forest Fires Other Burning Misc. Organic Solvent Use Misc. Total Total of Al1 Sources NOTE: One teraqram equals 10*2 grams 1.1 x 10® short tons. A value 50,000 metric tons. 1940 1950 1960 1970 4.5 6.8 10.0 11.1 0.0 0.1 0.2 0.2 0.5 0.5 0.2 0.2 0.0 0.1 0.2 0.3 0.2 0.4 0.5 0.5 5.2 7.9 11.1 12.3 0.0 0.0 0.0 0.0 0.1 0.1 0.1 0.1 0.0 0.0 0.0 0.0 3.8 2.5 1.5 0.8 3.9 2.6 1.6 0.9 0.8 1.2 1.1 1.6 0.4 0.5 0.7 0.7 0.1 0.1 0.1 0.1 0.0 0.0 0.0 0.0 0.1 0.1 0.2 0.2 1.0 2.1 2.4 4.0 0.8 1.2 1.6 2.1 3.2 5.2 6.1 8.7 0.4 0.4 0.5 0.5 0.5 0.6 0.9 1.3 0.9 1.0 1.4 1.8 3.1 1.7 0.9 0.7 0.6 0.6 0.5 0.3 0.8 1.3 1.7 2.3 4.5 3.6 3.1 3.3 17.7 20.3 23.3 27.0 (10^ metric tons) or approximately of zero indicates emissions of less than 9 ------- TABLE 6 1940-1970 SUMMARY OF ESTIMATED EMISSIONS OF CARBON MONOXIDE (TERAGRAMS/YEAR) Source Category 1940 .1950 1960 1970 Transportation Highway Vehicles 22.0 33.1 46.5 62.7 Ai rcraft 0.0 0.8 1.6 0.9 Railroads 3.7 2.8 0.3 0.3 Vessels 0.2 0.2 0.6 1.1 Other Off-Highway 3.4 6.7 8.0 6.8 Transportation Total 29.3 43.6 57.0 71.8 Stationary Source Fuel Combustion Electric Utilities 0.0 0.1 0.1 0.2 Industrial 0.4 0.5 0.6 0.7 Commercial Institutional 0.1 0.1 0.0 0.1 Residential 13.2 9.2 5.4 2.9 Fuel Combustion Total 13.7 9.9 6.1 3.9 Industrial Processes Chemicals 3.8 5.3 3.6 3.1 Petroleum Refining 0.2 2.4 2.8 2.0 Iron and Steel Mills 1.5 1.1 1.3 1.6 Primary Metal Smelting 0.0 0.1 0.3 0.6 Secondary Metals 1.0 1.4 1.0 1.1 Pulp Mills 0.1 0.2 0.3 0.6 Industrial Processes Total 6.6 10.5 9.3 9.0 Solid Waste Disposal Inci neration 2.0 2.5 2.5 2.7 Open Burning 1.3 1.8 2.6 3.7 Solid Waste Total 3.3 4.3 5.1 6.4 Mi seel 1aneous Forest Fires 22.8 12.8 6.7 5.1 Other Burning 3.7 3.7 3.3 2.1 Misc. Total 26.5 16.5 10.0 7.2 Total of Al1 Sources 79.4 84.8 87.5 98.3 NOTE: One teragram equals 10*2 grams (10^ metric tons) or approximately 1.1 x 10° short tons. A value of zero indicates emissions of less than 50,000 metric tons. 10 ------- TABLE 7 PARTICULATE NATIONAL EMISSION ESTIMATES (TERAGRAMS/YEAR) Source Cateqory 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Transportation Highway Vehicles 0.9 0.9 1.0 1.1 1.0 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 Ai rcraft 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Railroads 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.0 0.0 Vessels 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Other Off-Highway 0.1 0,1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Transportation Total 1.2 1.2 1.3 1.4 1.3 1.4 1.4 1.4 1.4 1.4 1.4 1.4 1.3 1.3 Stationary Source Fuel Combustion Electric Utilities 2.3 2.1 1.9 1.8 1.7 1.5 1.3 1.2 1.2 1.0 0.8 0.7 0.6 0.5 Industrial 1.6 1.2 0.9 0.8 0.7 0.6 0.5 0.5 0.4 0.5 0.5 0.5 0.4 0.4 Commercial Institutional 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Residential 0.5 0.5 0.4 0.4 0.4 0.4 0.5 0.6 0.6 0.7 0.8 0.9 0.9 1.0 Fuel Combustion Total 4.5 3.9 3.3 3.1 2.9 2.6 2.4 2.4 2.3 2.3 2.2 2.2 2.0 2.0 Industrial Processes 10.1 9.4 8.8 7.9 6.4 5.0 4.4 4.0 4.0 3.8 3.2 2.8 2.4 2.3 Solid Waste Disposal Incineration 0.4 0.4 0.3 0.3 0.3 0.3 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Open burning 0.7 0.5 0.4 0.3 0.3 0.3 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Sol id Uaste Total 1.1 0.9 0.7 0.6 0.6 0.6 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Hi seel 1aneous Forest Fires 0.7 0.9 0.7 0.7 0.8 0.6 0.9 0.7 0.7 0.8 1.0 0.8 0.6 0.8 Other burning 0.4 0.4 0.2 0.2 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Misc. Organic Solvent 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Hisc. Total 1.1 1.3 0.9 0.9 1.0 0.7 1.0 0.8 0.8 0.9 1.1 0.9 0.7 0.9 Total of All Sources 18.0 16.7 15.0 13.9 12.2 10.3 9.6 9.0 8.9 8.8 8.3 7.7 6.8 6.9 NOTE: One teragram equals 10^2 grams (10& metric tons) or approximately 1.1 x 10& short tons. A value of zero indicates emissions of less than 50,000 metric tons. ------- TABLE 8 SULFUR OXIDE NATIONAL EMISSION ESTIMATES (TERAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Transportation Highway Vehicles A1 rcraft Railroads Vessels Other Off-Highway 0.3 0.0 0.1 0.1 0.1 0.3 0.0 0.1 0.1 0.1 0.3 0.0 0.1 0.1 0.1 0.3 0.0 0.1 0.1 0.1 0.3 0.0 0.1 0.1 0.1 0.3 0.0 0.1 0.1 0.1 0.3 0.0 0.1 0.2 0.1 0.4 0.0 0.1 0.2 0.1 0.4 0.0 0.1 0.2 0.1 0.4 0.0 0.1 0.3 0.1 0.4 0.0 0.1 0.3 0.1 0.4 0.0 0.1 0.2 0.1 0.4 0.0 0.1 0.2 0.1 0.5 0.0 0.1 0.2 0.1 Transportation Total 0.6 0.6 0.6 0.6 0.6 0.6 0.7 0.8 0.8 0.9 0.9 0.8 0.8 0.9 Stationary Source Fuel Combustion Electric Utilities Industrial Commercial Institutional Residential 15.8 4.1 0.9 0.5 15.5 3.5 0.9 0.4 15.8 3.5 0.9 0.3 17.2 3.3 0.9 0.3 16.6 3.1 0.8 0.3 16.6 2.7 0.7 0.3 17.1 2.7 0.8 0.3 17.2 2.8 0.8 0.3 15.8 2.7 0.8 0.3 16.0 2.6 0.6 0.2 15.5 2.4 0.7 0.2 14.7 2.3 0.6 0.2 14.2 2.3 0.6 0.2 14.0 2.1 0.5 0.2 Fuel Combustion Total 21.3 20.3 20.5 21.7 20.8 20.3 20.9 21.1 19.6 19.4 18.8 17.8 17.3 16.8 Industrial Processes 6.2 5.8 6.2 6.3 5.6 4.7 4.6 4.4 4.1 4.2 3.5 3.7 3.2 3.1 Solid Waste Disposal Incineration Open Burning 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Sol Id Waste Total 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Miscellaneous Forest Fires Other burning Misc. Organic Solvent 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Misc. Total 0.1 0.1 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Total of A11 Sources 28.2 26.8 27.4 28.7 27.0 25.6 26.2 26.3 24.5 24.5 23.2 22.3 21.3 20.8 NOTE: One teragram equals 1012 grams (10& metric tons) or approximately 1.1 x 10*> short tons. A value of zero indicates emissions of less than 50,000 metric tons. ------- TABLE 9 NITROGEN OXIDE NATIONAL EMISSION ESTIMATES (TERAGRAMS/VEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Transportat ion Highway Vehicles Ai rcraft Railroads Vessels Other Off-Highway 6.0 0.1 0.6 0.1 0.8 6.4 0.1 0.6 0.1 0.8 7.1 0.1 0.7 • 0.1 0.9 7.5 0.1 0.7 0.1 0.9 7.1 0.1 0.7 0.1 0.9 7.1 0.1 0.7 0.1 0.9 7.4 0.1 0.7 0.1 1.0 7.6 0.1 0.7 0.1 1.0 7.6 0.1 0.7 0.2 1.1 7.4 0.1 0.8 0.2 1.1 7.2 0.1 0.8 0.1 1.0 7.4 0.1 0.7 0.2 0.9 7.0 0.1 0.7 0.2 0.9 7.0 0.1 0.6 0.2 0.9 Transportation Total 7.6 8.0 8.9 9.3 8.9 8.9 9.3 9.5 9.7 9.6 9.2 9.3 8.9 8.8 Stationary Source Fuel Combustion Electric Utilities Industrial Commercial Institutional Residential 4.5 3.9 0.3 0.4 4.7 3.8 0.3 0.4 5.0 3.9 0.3 0.4 5.3 3.9 0.3 0.4 5.3 3.7 0.3 0,4 5.2 3.4 0.3 0.4 5.6 3.7 0.3 0.4 6.0 3.7 0.3 0.4 5.9 3.7 0.3 0.4 6.2 3.6 0.3 0.4 6.4 3.0 0.3 0.4 6.5 3.0 0.3 0.4 6.2 3.0 0.3 0.4 6.3 2.8 0.2 0.4 Fuel Combustion Total 9.1 9.2 9.6 9.9 9.7 9.3 10.0 10.4 10.3 10.5 10.1 10.2 9.9 9.7 Industrial Processes 0.7 0.7 0.7 0.8 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.7 0.6 0.6 Solid Waste Disposal Incineration Open Burning 0.1 0.3 0.1 0.2 0.1 0.1 0.0 0.1 0.0 0.1 0.0 0.1 0.0 0.1 0.0 0.1 0.0 0.1 0.0 0.1 0.0 0.1 0.0 0.1 0.0 0.1 0.0 0.1 Sol id Waste Total 0.4 0.3 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Miscellaneous Forest Fires Other burning Misc. Organic Solvent 0.2 0.1 0.0 0.2 0.1 0.0 0.2 0.1 0.0 0.1 0.0 0.0 0.2 0.0 0.0 0.1 0.0 0.0 0.2 0.0 0.0 0.2 0.0 0.0 0.2 0.0 0.0 0.2 0.0 0.0 0.2 0.0 0.0 0.2 0.0 0.0 0.1 0.0 0.0 0.2 0.0 0.0 Misc. Total 0.3 0.3 0.3 0.1 0.2 0.1 0.2 0.2 0.2 0.2 0.2 0.2 0.1 0.2 Total of Al1 Sources 18.1 18.5 19.7 20.2 19.6 19.1 20.3 20.9 21.0 21.1 20.3 20.5 19.6 19.4 NOTE: One teragram equals than 50,000 metric 1012 grams tons. (10^ metric tons) or approximately 1, .1 x 10® short tons . A value of zero indicates emissions of less ------- TABLE 10 VOLATILE ORGANIC COMPOUND NATIONAL EMISSION ESTIMATES (TEKAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Transportation 8.7 6.0 Highway Vehicles 11.1 10.9 10.8 10.2 9.2 9.0 9.1 8.5 7.6 6.9 6.7 6.2 Aircraft 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Railroads 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Vessels 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Other Off-Highway 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.4 Transportation Total 12.3 12.2 12.1 11.5 10,5 10.3 10.4 10.0 9.8 8.9 8.2 8.0 7.5 7.2 Stationary Source Fuel Combustion Electric Utilities 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Industrial 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Commercial Institutional 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Residential 0.8 0.7 0.7 0.7 0.7 0.8 0.9 1.0 1.2 1.4 1.6 1.8 1.9 2.0 Fuel Combustion Total 0.9 0.8 0.8 0.8 0.8 0.9 1.0 1.1 1.3 1.5 1.7 1.9 2.0 2.1 Industrial Processes 8.7 8.4 9.1 9.4 9.0 8.1 8.7 9.0 9.6 9.5 8.9 8.0 7.1 7.5 Solid Waste Disposal Incineration 0.5 0.5 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.3 0.3 0.3 0.3 Open Burning 1.3 1.0 0.7 0.6 0.5 0.5 0.4 0.4 0.4 0.3 0.3 0.3 0.3 0.3 Solid Haste Total 1.8 1.5 l.l 1.0 0.9 0.9 0.8 0.8 0.8 0.7 0.6 0.6 0.6 0.6 Miscellaneous Forest Fires 0.7 0.9 0.7 0.6 0.7 0.5 0.9 0.7 0.7 0.8 0.9 0.8 0.6 0.8 Other burning 0.3 0.3 0.2 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Misc. Organic Solvent J?-3 2.2 2.3 2.2 2.1 1.9 1.9 1.9 1.9 2.0 1.9 1.6 1.5 1.6 Misc. Total 3.3 3.4 3.2 3.0 2.9 2.5 2.9 2.7 2.7 2.9 2.9 2.5 2.2 2.5 Total of All Sources 27.0 26.3 26.3 25.7 24.1 22.7 23.8 23.6 24.2 23.5 22.3 21.0 19.4 19.9 NOTE; One teragram equals 1012 grams (106 metric tons) or approximately 1.1 x 106 short tons . A value of zero indicates emissions of less than 50,000 metric tons. ------- TABLE 11 CARBON MONOXIDE NATIONAL EMISSION ESTIMATES (TERAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Transportat ion Highway Vehicles 62.7 61.7 62.3 59.7 55.1 54.2 56.4 53.4 52.8 48.7 45.3 44.2 41.1 41.2 Ai rcraft 0.9 0.9 0.9 0.8 0.9 0.9 0.9 0.9 1.0 1.0 1.0 1.0 1.0 1.0 Railroads 0.3 0.2 0.3 0.3 0.3 0.2 0.3 0.3 0.3 0.3 0.3 0.3 0.2 0.2 Vessels 1.1 1.2 1.3 1.3 1.3 1.4 1.4 1.4 1.5 1.4 1.4 1.4 1.4 1.4 Other Off-Highway 6.8 6.5 6.3 6.2 5.6 5.3 5.3 5.1 4.8 4.5 4.7 4.7 4.4 3.9 Transportation Total 71.8 70.5 71.1 68.3 63.2 62.0 64.3 61.1 60.4 55.9 52.7 51.6 48.1 47.7 Stationary Source Fuel Combustion • Electric Utilities 0.2 0.2 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Industrial 0.7 0.7 0.7 0.7 0.7 0.6 0.7 0.7 0.7 0.7 0.6 0.6 0.6 0.6 Commercial Institutional 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Residential 2.9 2.7 2.5 2.3 2.4 2.7 3.0 3.3 3.8 4.5 5.2 5.3 5.7 6.0 Fuel Combustion Total 3.9 3.7 3.6 3.4 3.5 3.7 4.1 4.4 4.9 5.6 6.2 6.3 6.7 7.0 Industrial Processes 9.0 8.7 8.4 8.5 8.1 6.9 7.1 7.2 7.1 7.1 6.3 5.9 4.4 4.6 Solid Uaste Disposal Inci neration 2.7 2.3 2.2 2.1 1.9 1.8 1.5 1.5 1.4 1.3 1.2 1.2 1.1 1.1 Open Burning 3.7 2.7 2.1 1.7 1.5 1.3 1.2 1.1 1.1 1.0 1.0 0.9 0.9 0.9 Solid Waste Total 6.4 5.0 4.3 3.8 3.4 3.1 2.7 2.6 2.5 2.3 2.2 2.1 2.0 2.0 Miscellaneous Forest Fires 5.1 6.7 5.2 4.5 5.6 4.0 6.4 5.1 5.0 5.8 6.9 5.8 4.3 5.7 Other burning 2.1 1.7 1.2 1.0 0.8 0.8 0.7 0.7 0.7 0.7 0.7 0.6 0.6 0.6 Misc. Organic Solvent 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Misc. Total 7.2 8.4 6.4 5.5 6.4 4.8 7.1 5.8 5.7 6.5 7.6 6.4 4.9 6.3 Total of Al1 Sources 98.3 96.3 93.8 89.5 84.6 80.5 85.3 81.1 80.6 77.4 75.0 72.3 66.1 67.6 NOTE: One teragram equals 10*2 grans (10& metric tons) or approximately 1.1 x 106 short tons . A value of zero indicates emissions of less than 50,000 metric tons. ------- TABLE 12 « LEAD NATIONAL EMISSION ESTIMATES (GIGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Transportation Highway Vehicles Off-Highway 156.0 7.6 174.8 7.8 190.4 7.6 166.0 6.3 129.6 4.7 118.1 4.5 127.5 4.9 119.5 4.7 108.2 4.2 90.8 3.8 56.4 3.0 43.9 2.5 44.4 2.5 38.7 2.0 Transportation Total 163.6 182.6 198,0 172.3 134.3 122.6 132.4 124.2 112.4 94.6 59.4 46.4 46.9 40.7 Stationary Source Fuel Combustion Electric Utilities Industrial (7i Commercial Institutional Residential 0.3 9.3 0.0 0.0 0.3 9.2 0.0 0.0 0.2 9.2 0.0 0.0 0.2 9.2 0.0 0.0 0.2 9.2 0.0 0.0 0.2 9.1 0.0 0.0 0.2 8.1 0.0 0.0 0.2 7.0 0.0 0.0 0.2 5.9 0.0 0.0 0.1 4.8 0.0 0.0 0.1 3.8 0.0 0.0 0.1 2.7 0.0 0.0 0.1 1.6 0.0 0.0 0.1 0.5 0.0 _0.0 Fuel Combustion Total 9.6 9.5 9.4 9.4 9.4 9.3 8.3 7.2 6.1 4.9 3.9 2.8 1.7 0.6 Industrial Processes 23.9 22.5 18.6 15.6 13.3 10.3 8.1 5.7 5.4 5.2 3.6 3.0 2.7 2.5 Solid Waste Disposal 6.7 6.2 5.7 5.4 5.1 4.8 4.3 4.1 4.0 4.0 3.7 3.7 3.1 3.1 Total of All Sources 203.8 220.8 231.7 202.7 162.1 147.0 153.1 141.2 127.9 108.7 70.6 55.9 54.4 46.9 NOTE: One gigagram equals 109 grams or 103 metric tons (1.1 * 103 short tons). ------- TABLE 13 PARTICULATE EMISSIONS FROM TRANSPORTATION (G1GAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Highway Vehicles Gasoline-powered Passenger cars Light trucks - 1 Light trucks - 2 Heavy duty vehicles Motorcycles 610 80 20 60 4 640 90 20 50 5 670 100 30 60 6 690 100 30 60 7 670 100 30 50 8 680 100 30 50 8 680 100 40 60 8 670 100 50 60 8 670 90 60 60 8 620 90 70 60 8 570 90 70 60 7 540 90 70 60 5 560 80 70 50 4 550 90 60 50 4 Total - Gasoline 770 810 870 890 860 870 890 890 890 850 800 770 760 750 Diesel-powered Passenger cars Light trucks Heavy duty vehicles 0 0 130 0 0 140 0 0 160 0 0 170 0 0 180 1 0 180 1 0 190 1 0 200 2 1 210 5 1 230 9 3 250 10 5 280 20 5 270 20 7 280 Total- Diesel 130 140 160 170 180 180 190 200 210 230 260 300 290 310 Highway Vehicle Total 900 950 1,020 1,060 1,040 1,050 1,080 1,090 1,100 1,070 1,050 1 ,070 1,050 1,060 Aircraft 100 90 90 70 80 80 70 70 70 70 70 70 70 80 Railroads 60 60 60 60 60 50 50 50 50 60 50 50 50 40 Vessels 40 30 30 30 30 30 20 30 30 30 30 30 30 20 Farm Machinery 40 40 50 40 50 50 60 60 70 70 60 60 60 60 Construction Machinery 10 10 20 20 10 10 20 20 20 20 20 20 20 20 Industrial Machinery 20 20 20 20 20 20 20 30 30 30 20 20 20 20 Other Off-highway Vehicles 4 4 4 5 4 5 5 5 5 5 5 5 5 5 Transportation Total 1,170 1,200 1,290 1,300 1,290 1,290 1,320 1 ,350 1,370 1,350 1,300 1 ,320 1,300 1,300 NOTE: One gigagram equals 10^ to independent rounding. grams or 10^ metric tons (1. 1 x 103 short tons). Total may di f fer sl ightly from summary table value due ------- TABLE 14 SULFUR OXIDE EMISSIONS FROM TRANSPORTATION (GIGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Highway Vehicles Gasoline-powered Passenger cars Light trucks - 1 Light trucks - 2 Heavy duty vehicles Motorcycles 120 20 6 10 0 120 20 6 10 0 130 20 7 20 0 130 30 8 10 0 130 30 8 10 0 130 30 9 10 0 140 30 10 10 1 150 30 10 10 1 150 30 20 10 1 150 30 20 10 1 140 30 20 10 1 140 30 20 10 0 150 30 20 10 0 160 30 20 10 0 Total - Gasoline 160 160 180 180 180 180 190 200 210 210 200 200 210 220 Diesel-powered Passenger cars Light trucks Heavy duty vehicles 0 0 100 0 0 no 0 0 130 0 0 140 0 0 140 0 0 140 0 0 150 1 0 160 1 0 170 3 1 180 5 2 200 10 3 220 10 3 210 10 4 220 Total - Diesel 100 no 130 140 140 140 150 160 170 180 210 230 220 230 Highway Vehicle Total 260 280 300 320 320 320 350 360 380 390 420 450 440 450 Ai rcraft 10 10 10 10 10 10 10 10 10 10 10 10 10 10 Railroads 130 110 120 120 120 110 120 120 110 120 120 110 no 100 Vessel s 150 130 120 140 140 140 160 180 210 250 270 250 200 180 Farm Machinery 30 30 30 30 30 30 40 40 40 50 40 40 40 40 Construction Machinery 10 10 20 20 20 20 20 20 20 20 20 20 20 20 Industrial Machinery 20 20 20 20 20 20 20 30 30 20 20 20 10 10 Other Off-highway Vehicles 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Transportation Total 610 590 620 660 660 650 720 760 800 860 900 900 830 810 NOTE: One giyagram equals 10^ grams or 10^ metric tons (1.1 x 10^ short tons). Total may differ slightly from summary table value due to to independent rounding. ------- TABLE 15 NITROGEN OXIDE EMISSIONS FROM TRANSPORTATION (GIGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Highway Vehicles GasolIne-powered Passenger cars Light trucks - 1 Light trucks - 2 Heavy duty vehicles Motorcycles 3,890 490 210 440 3 4,190 550 220 430 4 4,510 630 270 480 5 4,710 650 300 470 6 4,370 610 300 460 7 4,370 600 310 430 7 4,410 640 380 440 6 4,410 660 450 420 7 4,360 650 510 410 7 3,960 640 530 380 10 3,660 640 520 360 10 3,490 690 570 350 10 3,470 640 510 300 10 3,380 660 510 290 10 Total- Gasoline 5,030 5,390 5,890 6,140 5,750 5,720 5,880 5,950 5,940 5,520 5,190 5,110 4,930 4,850 Diesel-powered Passenger cars Light trucks Heavy duty vehicles 0 0 950 0 0 1,050 0 0 1,220 0 0 1,340 0 0 1,390 1 0 1,410 1 0 1,520 2 0 1,620 3 1 1,710 8 2 1,840 10 6 2,020 20 10 2,230 30 10 2,080 30 10 2,090 Total - Diesel 950 1,050 1,220 1,340 1,390 1,410 1,520 1,620 1,710 1,850 2,040 2,260 2,120 2,130 Highway Vehicle Total 5,990 6,440 7,110 7,480 7.140 7,120 7,410 7,570 7,650 7,380 7,230 7,370 7,040 6,980 A1 rcraft no no 100 100 100 100 100 100 110 120 110 no no no Railroads 640 620 690 730 730 660 690 700 710 750 750 710 660 650 Vessels 90 100 100 120 110 120 130 150 170 180 150 190 160 150 Farm Machinery 400 410 430 410 440 430 490 510 540 560 460 480 470 440 Construction Machinery 180 190 200 220 190 190 210 250 260 230 230 200 200 200 Industrial Machinery 220 230 240 240 250 240 250 260 260 260 260 240 220 220 Other Off-highway Vehicles 10 9 10 10 10 10 10 10 10 10 10 10 10 10 Transportation Total 7,640 8,120 8,880 9,310 8,970 8,890 9,290 9,550 9,710 9,490 9,200 9,310 8,870 8,760 NOTE: One glgagram equals 10" grams or 10^ metric tons (1.1 x 10^ short tons). Total may differ slightly from summary table value due to Independent rounding. ------- TABLE 16 VOC EMISSIONS FROM TRANSPORTATION (GIGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Highway Vehicles Gasoli ne-powered Passenger cars 8,530 8,340 8,040 7,560 6,760 6,520 6,400 6,020 5,770 5,010 4,440 4,080 3,940 3,860 Light trucks - 1 1,130 1,120 1,220 1,140 1,040 990 1,060 1,030 970 900 870 910 800 800 Light trucks - 2 450 430 500 520 500 520 650 730 830 860 790 840 720 680 Heavy duty vehicles 830 740 800 730 640 610 640 580 570 540 530 530 440 420 Motorcycles 80 120 140 160 170 180 180 180 180 150 110 80 60 60 Total- Gasoline 11,020 10,750 10,700 10,110 9,110 8,820 8,930 8,540 8,320 7,460 6,740 6,440 5,960 5,820 01esel-powered Passenger cars 0 0 0 0 0 0 0 0 1 2 3 4 4 5 Light trucks 0 0 0 0 0 0 0 0 0 1 2 3 3 3 Heavy duty vehicles 100 110 120 130 130 130 150 160 170 180 200 220 210 220 Total - Diesel 100 110 120 130 130 130 150 160 170 180 200 220 220 230 Highway Vehicle Total 11,120 10,860 10,820 10,230 9,240 8,950 9,080 8,700 8,490 7,640 6,930 6,660 6,180 6,040 Ai rcraft 250 230 210 190 190 190 170 170 180 180 180 160 160 170 Rail roads 160 150 170 180 180 160 170 170 170 180 180 170 160 160 Vessels 330 350 380 390 380 400 410 420 430 420 400 430 410 410 Farm Machinery 250 240 240 240 230 220 230 220 220 220 190 180 180 160 Construction Machinery 40 40 40 40 40 30 40 40 40 40 40 40 30 30 Industrial Machinery 120 120 130 120 90 80 90 90 90 80 80 100 90 80 Other Off-highway Vehicles 110 130 140 150 140 160 160 160 160 160 160 160 160 160 Transportation Total 12,380 12,120 12,130 11,540 10,490 10,190 10,350 9,970 9,780 8,920 8,160 7,900 7,370 7,210 NOTE: One gigagram equals 109 grans or 103 metric tons (1.1 x 103 short tons). Total may differ slightly from summary table value due to independent rounding. ------- TABLE 17 CARBON MONOXIDE EMISSIONS FROM TRANSPORTATION (G1GAGRAHS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Highway Vehicles Gasolf ne-powered 26,520 Passenger cars 47,610 46,990 45,990 43,870 40,170 39,390 39,660 36,920 35,790 32,000 29,200 27,280 26,360 Light trucks - 1 5,650 5,760 6,230 5,900 5,650 5,490 6,180 6,010 5,860 5,690 5,480 5,920 5,240 5,310 Light trucks - 2 2,020 1,920 2,200 2,300 2,250 2,390 3,100 3,470 4,030 4,230 4,000 4,400 3,860 3,850 Heavy duty vehicles 6,880 6,390 7,060 6,750 6,140 5,990 6,470 6,000 6,060 5,800 5,690 5,730 4,820 4,700 Motorcycles 240 360 400 450 510 510 520 510 520 430 310 230 160 160 Total - Gasoline 62,400 61,420 61,880 59,270 54,720 53,770 55,930 52,910 52,260 48,150 44,680 43,560 40,440 40,540 Diesel-powered Passenger cars 0 0 0 0 0 0 1 1 2 4 7 10 10 20 Light trucks 0 0 0 0 0 0 0 0 1 2 3 6 6 7 ro Heavy duty vehicles 290 320 370 400 390 390 440 470 500 530 590 680 630 660 Total - Diesel 290 320 370 400 390 390 440 470 500 530 600 690 650 690 Highway Vehicle Total 62,690 61,750 62,250 59,680 55,110 54,170 56,370 53,390 52,770 48,670 45,290 44,250 41,090 41,230 Aircraft 900 890 860 840 860 880 860 900 960 990 990 960 950 980 Rail roads 250 240 260 270 270 240 250 260 260 270 270 250 240 230 Vessels 1,150 1,220 1,230 1,350 1,300 1,360 1,400 1,420 1,470 1,420 1,380 1,440 1,390 1,400 Farm Machinery 3,570 3,450 3,140 3,250 3,000 2,930 2,780 2,600 2,370 2,240 2,040 1,880 1,780 1,460 Construction Machinery 580 510 470 450 430 370 410 360 340 370 460 370 320 260 Industrial Machinery 1,780 1.710 1,810 1,580 1,230 1,060 1,070 1,100 1,070 820 1,110 1,330 1,190 1,030 Other Off-highway Vehicles 840 870 910 950 960 990 1,000 1,020 1,050 1,080 1,090 1,100 1,110 1,120 Transportation Total 71,760 70,640 70,930 68,370 63,160 62,000 64,140 61,050 60,290 55,860 52,630 51,580 48,070 47,710 NOTE: One glgagram equals 10" grams or 103 metric tons (1.1 * 103 short tons). Total may differ slightly from summary table i value due to Independent rounding. ------- TABLE 18 PARTICULATE EMISSIONS FROM FUEL COMBUSTION (GIGAGRAHS/VEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Coal Electric utilities Industrial Residential/Commercial 2,220 1,300 120 1,960 920 110 1,750 650 80 1,690 550 80 I ,560 440 70 1,4 20 360 60 1,150 250 50 1,060 230 50 1,050 220 50 860 250 50 720 250 50 640 280 50 490 220 50 480 210 60 Coal Total 3,640 2,990 2,480 2,320 2 ,070 1,840 1,450 1,340 1,320 1,160 1,020 970 760 750 Fuel Oil Electric util ities Industrial Residential/Commercial 110 80 80 120 80 70 120 80 70 130 90 70 130 80 60 120 70 60 120 80 60 140 90 60 140 80 60 120 70 50 110 60 50 90 50 40 70 50 40 60 30 30 Fuel Oil Total 270 270 270 290 270 250 260 290 280 240 220 180 160 120 Natural Gas Electric utilities Industrial Residential/Commercial 6 20 10 6 20 10 6 20 10 6 20 10 5 20 10 5 20 10 5 20 10 5 20 10 5 20 10 5 20 10 6 20 10 6 20 10 5 20 10 4 20 9 Natural Gas Total 36 36 36 36 35 35 35 35 35 35 36 36 35 33 Wood Industrial Residential 140 380 130 360 140 360 140 330 130 350 90 400 90 450 100 510 100 590 100 700 100 800 90 830 80 890 90 940 Hood Total 520 490 500 470 480 490 540 610 • 690 800 900 920 970 1,030 Other Fuels Industrial Residential 40 4 40 4 40 4 40 4 30 3 40 3 40 3 30 3 30 3 30 3 30 2 20 2 20 2 20 2 Other Fuels Total 44 44 44 44 33 43 43 33 33 33 32 22 22 22 Fuel Combustion Total 4,510 3,830 3,330 3,160 2 ,890 2,660 2,330 2,310 2,360 2,270 2,210 2,130 1,950 1,950 NOTE: One gigagram equals 10^ grams or 10^ metric tons (1.1 x 10^ short tons). Total may differ slightly from summary table value due to independent rounding. ------- TABLE 19 Source Category 1970 1971 Coal Electric utilities Industrial Residentlal/Commerclal 14,330 2.840 340 14,080 2,300 320 Coal Total 17,510 16,700 Fuel Oil Electric utilities Industrial Residentlal/Commercial 1,460 1,140 1.000 1,460 1,070 950 Fuel Oil Total 3.600 3,480 Natural Gas Electric utilities Industrial Residential/Commercial 1 2 2 1 2 2 Natural Gas Total 5 5 Wood Industrial Residential 3 5 3 4 Wood Total 8 7 Other Fuels Industrial Residential 160 20 140 20 Other Fuels Total 180 160 Fuel Combustion Total 21,300 20,350 NOTE: One gigagram equals 10' grams or 10^ metric Independent rounding. SULFUR OXIOE EMISSIONS FROM FUEL COMBUSTION (GIGAGRAMS/YEAR) 1972 1973 1974 1975 1976 1977 14,410 2,180 230 15,600 1,970 220 15,100 1,800 240 15,200 1,700 210 15,650 1,490 200 15,580 1,450 200 16,820 17.790 17,140 17.110 17,340 17,230 1,390 1,170 990 1,570 1.180 930 1,520 1,110 860 1,380 880 760 1,440 1,090 870 1,630 1.210 850 3,550 3,680 3,490 3,020 3,400 3.690 1 2 2 1 2 2 1 2 2 1 2 2 1 2 2 1 2 2 5 5 5 5 5 5 3 4 3 4 3 4 3 5 4 6 4 6 7 7 7 8 10 10 140 10 130 10 160 10 100 10 140 10 110 10 150 140 170 no 150 120 20,530 21,620 20,810 20,250 20,900 21,060 is (1.1 X lO^ short tons). Total may differ slightly 1978 1979 1980 1981 1982 1983 14,080 1,500 230 14,550 1,610 190 14,190 1,380 140 13,580 1,560 170 13.270 1.500 210 13,250 1,540 220 15.810 16,350 15,710 15,310 14.980 15.010 1.680 1,100 780 1.450 910 640 1,310 850 720 1,130 680 560 950 700 550 770 440 400 3,560 3,000 2,880 2,370 2,200 1,610 1 2 2 1 2 2 1 2 2 1 2 2 1 2 2 1 2 2 5 5 5 5 5 5 4 7 4 8 4 10 4 10 4 10 4 10 11 12 14 14 14 14 130 9 130 9 120 6 100 6 80 5 80 5 139 139 126 106 85 85 19,520 19,510 18,740 17.800 17.280 16,720 from summary table value due to ------- TABLE 20 NITROGEN OXIDE EMISSIONS FROM FUEL COMBUSTION (GIGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Coal Electric utilities Industrial Residential/Commercial 3,170 700 40 3,230 580 40 3,410 560 40 3,740 510 40 3,780 480 40 3,880 470 40 4,270 440 30 4,550 420 40 4,470 420 30 4,820 460 30 5,150 400 30 5,250 460 30 5,200 450 30 5,410 460 30 Coal Total 3,910 3,850 4,010 4,290 4,300 4,390 4,740 5,010 4,930 5,310 5,580 5,740 5,680 5,900 Fuel Oil Electric utilities Industrial Residential/Commercial 390 300 300 480 310 300 600 320 300 700 340 300 670 310 280 600 270 260 620 340 290 730 360 280 680 350 280 570 260 230 440 220 220 380 190 180 270 200 170 260 150 140 Fuel 011 Total 990 1,090 1,220 1,340 1,260 1,130 1,250 1,370 1,310 1,060 880 750 640 550 Natural Gas Electric utilities Industrial Residential/Commercial 940 2,770 330 960 2,830 340 960 2,900 350 870 2,930 340 830 2,820 330 740 2,570 340 710 2,800 350 730 2,810 330 720 2,790 340 790 2,710 350 830 2,240 330 820 2,140 320 730 2,230 330 620 2,020 300 Natural Gas Total 4,040 4,130 4,210 4,140 3,980 3,650 3,860 3,870 3,850 3,850 3,400 3,280 3,290 2,940 Wood Industrial Residential 70 30 70 30 70 30 70 30 70 30 70 30 80 40 80 40 90 50 90 60 90 60 90 70 80 70 90 70 Wood Total 100 100 100 100 100 100 120 120 140 150 150 160 150 160 Other Fuels Industrial Residential 50 60 50 50 50 60 50 50 50 50 50 40 60 50 50 40 60 40 70 30 70 30 60 30 60 20 60 20 Other Fuels Total 110 100 110 100 100 90 no 90 100 100 100 90 80 80 Fuel Combustion Total 9,150 9,270 9.650 9,970 9,740 9,360 10,080 10,460 10,330 10,470 10,110 10,020 9,840 9,630 NOTE: One gigagram equals 10^ grams or 103 metric tons (1.1 x 10^ short tons). Total may differ slightly from summary table value due to independent rounding. ------- TABLE 21 VOC EMISSIONS FROM FUEL COMBUSTION (GIGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Coal Electric util ities Industrial Residential/Commercial 20 4 60 20 3 50 20 3 30 20 3 30 20 3 20 20 3 20 20 3 20 20 2 10 20 2 10 30 3 10 30 2 10 30 3 10 30 3 10 30 3 10 Coal Total 84 73 53 53 43 43 43 32 32 43 42 43 43 43 Fuel Oil Electric utilities Industrial Residential/Commercial 7 4 8 9 5 8 10 5 8 10 5 8 10 5 7 10 5 7 10 5 8 20 6 7 20 6 7 10 4 6 8 3 6 6 3 5 5 3 4 4 3 4 Fuel Oil Total 19 22 23 23 22 22 23 33 33 20 17 14 12 11 Natural Gas Electric utilities Industrial Resident ial/Commercial 5 70 20 5 70 20 5 70 20 5 70 20 5 70 20 4 60 20 4 70 20 4 70 20 4 70 20 5 70 20 5 50 20 5 50 20 4 50 20 4 50 20 Natural Gas Total 95 95 95 95 95 84 94 94 94 95 75 75 74 74 Wood Industrial Residential 40 700 40 660 40 660 40 620 40 640 40 740 50 840 50 940 50 1,130 50 1,380 50 1,600 50 1,730 50 1,870 50 2,000 Wood Total 740 700 700 660 680 780 890 990 1,180 1,430 1,650 1 ,780 1,920 2,050 Other Fuels Industrial Residential 7 2 7 2 8 2 7 2 7 2 10 2 10 2 9 2 10 2 10 1 10 1 9 1 7 I 8 1 Other Fuels Total 9 9 10 9 9 12 12 11 12 11 11 10 8 9 Fuel Combustion Total 950 900 880 840 850 940 1,060 1,160 1,350 1,600 1,800 1,920 2,060 2,190 NOTE: One gigagram equals 10^ grams or 10^ metric tons (1.1 x 10^ short tons). Total may differ slightly from summary table value due to independent rounding. ------- TABLE 22 CARUON MONOXIDE EMISSIONS FROM FUEL COMBUSTION (GIGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Coal Electric utilities Industrial Residential/Comme rc i a 1 100 90 510 100 80 450 100 70 280 120 70 230 120 60 220 120 60 170 130 60 150 140 50 140 140 60 130 160 60 120 170 50 100 180 60 110 180 60 120 190 60 130 Coal Total 700 630 450 420 400 350 340 330 330 340 320 350 360 380 Fuel Oil Electric utilities Industrial Residential/Commercial 40 40 50 50 40 50 60 50 60 70 50 50 70 40 50 60 40 50 70 50 50 80 50 50 80 50 50 60 30 50 40 30 40 40 30 30 30 30 30 30 20 30 Fuel Oil Total 130 140 170 170 160 150 170 180 180 140 no 100 90 80 Natural Gas Electric utilities Industrial Residential/Commercial 80 420 70 90 430 70 90 440 70 80 440 70 70 430 70 70 390 70 70 420 70 70 420 70 70 420 70 80 410 70 80 350 70 80 330 60 70 340 70 60 310 70 Natural Gas Total 570 590 600 590 570 530 560 560 560 560 500 470 480 440 Wood Industrial Residential 10 2,310 110 2,200 120 2,190 120 2,040 120 2,140 110 2,450 130 2,780 130 3,120 150 3,640 150 4,340 140 5,020 150 5,130 140 5,500 150 5,810 Uood Total 2,420 2,310 2,310 2,160 2,260 2,560 2,910 3,250 3,790 4,490 5,160 5,280 5,640 5,960 Other Fuels Industrial Residential 10 10 10 10 20 10 10 10 10 10 20 10 20 10 20 10 20 10 20 8 20 6 20 6 20 5 20 5 Other Fuels Total 20 20 30 20 20 30 30 30 30 28 26 26 25 25 Fuel Combustion Total 3,840 3,690 3,560 3,360 3,410 3,620 4,010 4,350 4,890 5,560 6,120 6,230 6,600 6,880 NOTE: One gigagram equals 10^ grams or 10^ metric tons (1.1 x 10^ short tons). Total may differ slightly from summary table value due to independent rounding. ------- TAULE 23 PARTICULATE EMISSIONS FROM INDUSTRIAL PROCESSES (GIGAGRAMS/VEAR) ro Source Category Cattle Feed lots (0211) Cotton Ginning (0724) Metallic Ore Mining (10) Coal Mining (1211) Crushed Stone (142) Sand and Gravel (144) Clays (145) Potash/Phosphate Rock (1474,1475) Feed and Grain Milling (204) Lumber and Plywood (24) Pulp Hills (261.262) Chemicals (28) Petroleum Refining (2911) Asphalt Paving and Roofing (295) Glass (321 ,322) Cement (3241) Brick and Tile (3251) Concrete, Lime, Gypsum (327) Clay Sintering (3295) Iron and Steel (3312) Ferroalloys (3313) Iron and Steel Foundries (332) Primary Nonferrous Smelters (333) Secondary Nonferrous Smelters (334,336) Grain Elevators (4421 ,5153) TOTAL 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 30 20 20 20 20 30 20 20 20 30 20 10 530 490 400 480 400 320 260 180 210 210 180 200 no 110 350 300 300 280 250 250 260 260 250 280 290 290 290 280 1,350 1,260 1,210 1,180 980 760 660 560 610 570 450 380 340 360 50 50 50 50 50 40 40 50 50 50 40 40 30 30 1,610 1,350 1,140 950 560 290 220 210 210 150 130 70 60 70 40 40 40 40 40 30 30 30 30 30 30 10 10 10 80 80 80 70 60 60 50 50 60 50 50 50 60 40 80 80 90 90 80 70 80 90 90 80 70 70 60 70 520 460 440 310 270 180 150 150 110 no 110 80 90 90 220 180 170 150 130 100 100 110 110 110 100 90 70 80 60 70- 70 70 70 70 60 60 60 50 50 40 40 30 560 560 550 590 500 320 220 130 120 130 no 90 90 90 40 50 50 50 40 40 40 40 30 30 30 30 30 30 1,380 1,350 1,190 870 690 560 540 550 560 480 350 280 210 230 40 50 50 50 40 30 40 40 40 40 30 20 20 20 520 430 390 370 320 240 210 150 140 130 120 100 80 80 100 100 100 90 70 40 30 20 10 10 10 10 10 10 1,190 970 970 890 760 570 500 440 450 400 310 300 200 210 160 140 150 160 150 90 80 70 60 40 30 30 10 10 170 170 160 130 120 80 80 70 70 60 50 40 40 40 320 300 280 250 200 170 140 100 100 100 90 80 60 60 50 60 50 50 50 50 50 40 40 50 40 40 30 30 670 790 730 720 570 590 550 500 500 550 440 440 450 270 10,130 9,350 8,770 7,910 6,440 5,030 4,420 3,950 3,960 3,760 3,170 2,830 2,420 2,310 NOTE: One glgagram equals 109 grams or 103 metric tons (1.1 * 103 short tons). Independent rounding of data. Total may differ slightly from sum of source category totals due to ------- TABLE 24 SULFUR OXIDE EMISSIONS FROM INDUSTRIAL PROCESSES (GIGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Natural Gas Production (1311) 100 100 120 150 160 160 130 120 130 140 140 150 140 160 Pulp Mills (261,262) 110 100 110 110 110 100 110 100 100 100 110 110 100 110 Sulfuric Acid (2819) 540 530 570 570 440 330 250 260 260 250 250 220 170 180 Carbon Black (2895) 0 0 10 10 10 10 10 10 10 10 10 10 10 10 Petroleum Reftning (2911) 700 750 790 850 850 830 850 890 900 880 840 770 740 740 Glass (321,322) 20 20 20 30 30 30 30 30 30 30 30 30 30 30 Cement (3241) 560 550 560 560 540 460 510 580 630 630 570 550 480 520 Lime (3274) 30 30 30 30 30 30 30 30 30 30 30 30 20 20 ,Iron and Steel (3312) 480 390 440 510 460 480 450 450 430 440 390 370 240 220 Primary Copper (3331) 3,180 2,840 3,130 3,210 2,710 2,140 2,040 1,770 1,370 1,450 990 1,270 970 880 Primary Lead and Zinc (3332,3333) 410 360 310 190 160 110 110 90 100 120 70 70 160 140 Primary Aluminum (3334) 70 70 70 80 80 60 70 80 80 80 90 80 60 60 Secondary Lead (3341) 20 . 20 20 20 20 20 30 30 30 40 30 30 30 20 TOTAL 6,210 "5,750 6,170 6,320 5,610 4,740 4,610 4,430 4,100 4,210 3,540 3,690 3,150 3,090 NOTE: One gigagram equals 10^ grams or 10^ metric tons (l.J x JO* short tons). Total may differ slightly from sumof source category totals due to Independent rounding of data. ------- TABLE 25 NITROGEN OXIDE EMISSIONS FROM INDUSTRIAL PROCESSES (GIGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Pulp Mills (261,262) 20 20 30 30 30 20 30 30 30 30 30 30 30 30 Organic Chemicals (286) 60 70 60 80 70 60 60 60 60 70 50 50 40 50 Ammonia (2873) 30 40 40 40 40 40 40 40 40 50 50 50 40 30 Nitric Acid (2873) 150 140 140 140 130 110 110 110 100 100 100 90 60 50 Petroleum Refining (29II) 220 230 230 240 240 240 240 260 260 250 240 210 200 200 Glass (321,322) 40 40 50 50 50 50 50 60 60 60 50 60 50 50 Cement (3241) 90 90 100 100 100 80 90 90 100 100 90 80 70 80 Lime (3274) 20 20 20 20 20 20 20 20 20 20 20 20 20 20 Iron and Steel (3312) 70 70 70 80 80 70 70 70 80 70 60 60 40 40 TOTAL 710 720 730 770 750 690 710 740 750 740 690 650 560 560 NOTE: One glgagram equals 10" grains or 103 metric tons (1.1 x 103 short tons). Total may differ slightly from sum of source category totals due to Independent rounding of data. ------- TABLE 26 VOLATILE ORGANIC COMPOUND EMISSIONS FROM INDUSTRIAL PROCESSES (GIGAGRAMS/YEAR) Source Category Crude oil production, storage arid transfer {1311,4463) Food and beverages (20) Textiles (22) Graphic arts (27) Plastics (2821,3079) Organic chemicals (286) Other chemicals (28) Petroleum refining (2911) Rubber tires (3011) co Iron and steel (3312) o Petroleum product storage and transfer (5171 ,5541) Dry cleaning (721) Adhesivesl Degreas ingl Solvent extraction processes1 Surface coatingl Other organic solvent use1 TOTAL iThts is a general category which includes process emissions from organic solvent use in a wide variety of industries. Thus no specific SIC is given. NOTE: One gigagram equals 10g grams or 103 metric tons (1.1 x 103 short tons). Total may differ slightly from sum of source category totals due to independent rounding of data. 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 550 560 560 560 540 530 530 550 570 570 560 540 530 530 190 190 190 180 180 170 170 170 180 180 170 180 180 180 10 10 10 10 20 20 20 20 20 20 20 20 20 10 290 270 310 320 300 250 280 290 350 350 340 260 240 280 380 360 410 430 410 350 390 410 470 490 460 390 350 420 570 600 680 740 770 690 810 820 820 810 710 650 490 570 590 530 530 550 520 460 510 560 560 580 530 540 470 500 720 760 790 820 850 880 890 940 970 970 970 960 900 810 50 50 60 60 50 50 50 60 60 50 40 50 40 50 110 80 100 110 100 90 100 90 90 90 80 70 50 40 1,570 1,640 1,720 1,780 1,730 1,740 1,780 1,780 1,810 1,660 1,490 1,440 1,370 1,370 240 230 240 240 240 230 250 260 290 290 290 240 210 210 50 40 50 50 50 40 40 50 60 60 50 40 40 40 640 560 590 600 540 450 490 490 550 560 510 420 360 410 40 40 40 40 40 30 30 40 50 40 40 40 30 40 2,390 2,230 2,550 2,570 2,340 1,880 2,090 2,190 2,510 2,500 2,320 1,820 1,560 1,780 270 240 270 290 280 220 250 290 280 300 290 300 250 260 8,670 8,410 9,100 9,360 8,960 8,090 8,690 9,020 9,620 9,500 8,870 7,980 7,100 7,490 ------- TABLE 27 CARBON MONOXIDE EMISSIONS FROM INDUSTRIAL PROCESSES (GIGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Pulp Mills (261,262) 550 550 590 610 610 550 620 630 650 660 720 720 700 760 Inorganic Pigments (2816) 20 20 20 20 30 20 30 30 30 30 30 30 30 30 Charcoal (2861) 50 50 50 50 40 30 30 40 40 50 40 40 30 30 Organic Chemicals (286) 310 320 380 400 410 410 410 450 490 510 450 470 420 470 Ammonia (2873) 100 110 no 110 110 120 120 130 120 130 140 140 no 100 Carbon Black (2895) 2,600 2,380 1,780 1,890 1,680 1,420 1,550 1,760 1,630 1,590 1,290 1,320 950 1,030 Petroleum Refining (2911) 2,000 2,070 2,100 2,140 2,060 2,040 1,960 1,870 1,780 1,690 1,600 1,110 690 630 Asphalt Roofing (2952) 10 10 10 10 10 10 10 20 20 20 10 10 10 10 Lime (3274) 10 10 20 20 20 10 20 20 20 20 10 10 10 10 Iron and Steel (3312) 1,620 1,470 1,560 1,580 1,460 1,100 1,180 1,160 1,210 1,200 910 990 640 660 Iron Foundries (3321) 1,090 1,160 1,180 1,060 920 590 590 470 440 410 310 290 280 280 Primary Aluminum (3334) 590 580 610 670 730 580 630 680 720 750 760 740 540 550 TOTAL 8,950 8,730 8,410 8,550 8,080 6,870 7,150 7,230 7,140 7,060 6,340 5,870 4,420 4,580 NOTE: One gigagram equals 10^ grams or 10^ metric tons (1.1 x 10^ short tons). Total may differ slightly from sum of source category totals due to independent rounding of data. ------- TABLE 28 LEAD EMISSIONS FROM INDUSTRIAL PROCESSES (MEGAGRAMS/YEAR) Source Category 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 Iron & Steel Industry 3,087 2,441 2,352 2,326 1,772 1,073 913 873 911 769 476 468 335 369 Primary Nonferrous Metals 12,350 11,960 8,414 7,116 6,416 5,569 3,465 1,519 1,463 1,316 1,038 859 874 872 Secondary Nonferrous Metals 5,612 5,484 4,650 3,286 2,890 1,905 1,682 1,510 1,440 1,391 1,020 883 784 724 Mineral Products 764 716 630 464 422 440 400 374 378 296 272 254 202 171 Miscellaneous 2,050 1,879 2,221 2,448 1,793 1,338 1,599 1,411 1,227 1,389 778 585 515 389 Total Industrial 23,863 22,480 18,567 15,640 13,293 10,325 8,059 5,687 5,419 5,161 3,584 3,049 2,710 2,525 NOTE: One megagram equals 10^ grams or one metric ton (1.1 short ton). ------- 3. METHODS The generation of an emission inventory involves many steps to achieve the desired result, which is to estimate the amount of emissions for selected pollutants in a defined geographical area. Ideally, nationwide emission estimates should result from a summation of county, State, and regional data in which each component is reported separately. The National Emissions Data System (NEDS) uses this procedure. The methods used to prepare data for this publication are as similar as possible to those used for NEDS data preparation. Since NEDS uses a more detailed procedure involving calculation of emissions for individual sources and summation of these individual emission totals to produce national totals, there is a much greater chance for errors or omissions to occur in the NEDS data. Because of the basic similarity of techniques, discrepancies between national totals reported herein and those given in NEDS reports are due largely to incomplete data reporting and errors in the NEDS data. The quality of NEDS data over time has improved so that the differences between NEDS emission reports for 1977 and later years and national emission totals determined by the procedure used for this publication are not as great as in earlier NEDS reports. Moreover, historical NEDS data are not revised to account for updated emission factors, errors or omissions in the data. As a result annual NEDS publications do not necessarily represent a consistent trend in estimated emissions. Because it is impossible to test every pollutant source indivi- dually, particularly area sources, an estimating procedure must be used. In order to do this, however, one must either estimate the emissions directly or estimate the magnitude of other variables that can then be related to emissions. These indicators include fuel con- sumption, vehicle miles, population, sales, tons of refuse burned, raw materials processed, etc., which are then multiplied by appropriate emission factors to obtain emission estimates. The limitations and applicability of emission factors must be understood. In general, emission factors are not precise indicators of emissions from a single source; rather, they are quantitative estimates of the average rate of pollutant released as a result of some activity. They are most valid when applied to a large number of sources and processes. If their limitations are recognized, emission factors are extremely useful in determining emission levels. A detailed discussion of emission factors and related information is contained in Reference 2. The emission factor thus relates quantity of pollutants emitted to indicators such as those noted above, and is a practical approach for determining estimates of emissions from various source categories. A basic discussion of trends is meaningful only when there is a common basis for evaluation. It was necessary, therefore, to quantify emissions using the same criteria for each year. This meant using the 33 ------- same estimation techniques, using equal or equivalent data sources, covering the same pollutant sources, and using compatible estimates of pollutant control levels from year to year. Estimates for previous years were updated using current emission factors and including the most recent information available. The criteria used in calculating emissions was the same for all years. The methodology used in generation of emission estimates for individual source categories follows. 3.1 Transportation 3.1.1 Motor Vehicles Emission estimates from gasoline-and diesel-powered motor vehicles were based upon vehicle-mile tabulations and emission factors. Eight vehicle categories are considered; light duty gasoline (mostly passen- ger cars), light duty diesel passenger cars, light duty gasoline trucks (trucks less than 6000 pounds in weight), light duty gasoline trucks 6000 to 8500 pounds in weight, light duty diesel trucks, heavy duty gasoline trucks and buses, and heavy duty diesel trucks and buses, and motorcycles. The emission factors used are based on the latest available data from Reference 3. The M0BILE3 model, developed by the EPA Office of Mobile Sources was used to calculate emission factors for each year. The current M0BILE3 model does not provide emission factors for California. The earlier model, M0BILE2, was used for California. The use of M0BILE2 for California may cause V0C emissions from highway vehicles to be slightly underestimated, but should have a negligible effect on CO and N0X emissions. The emission factors are weighted to consider the approximate amount of motor vehicle travel in low altitude areas, high altitude areas, and California to obtain overall national average emission factors. For each area a representative average annual temperature, together with national averages for motor vehicle model year distributions and hot/cold start vehicle operation percentages were used to calculate the emission factors. Average speed is taken into account according to the published distribution of vehicle-miles travelled (VMT) as published in Reference 4. The published VMT are divided into three road categories corresponding to roads with assumed average speeds of 55 miles per hour for interstates and other primary highways, 45 miles per hour for other rural roads, and 19.6 miles per hour for other urban streets. For 1940 and 1950, average speeds were assumed to be 45, 35 and 19.6 miles per hour for these roadway classifications. Lead emission estimates from gasoline-powered-motor vehicles, were based on highway gasoline consumption, lead content of gasoline, per- cent unleaded gasoline, and emission factors. The gasoline consump- tion is based on highway gasoline usage as published in Reference 4. The lead content of gasoline was obtained from Reference 13 for 1970-74 and Reference 31 for 1975-83. The percent unleaded gasoline is obtained from Reference 6. The emission factor was also obtained from Reference 31. 34 ------- 3.1.2 Aircraft Aircraft emissions are based on emission factors and aircraft acti- vity statistics reported by the Federal Aviation Administration.5 Emissions are based on the number of 1anding-takeoff (LTO) cycles. Any emissions in cruise mode, which is defined to be above 3000 feet (1000 meters) are ignored. Average emission factors for each year, which take into account the national mix of aircraft types for general aviation, military, and commercial aircraft, are used to compute the emi ssions. 3.1.3 Railroads The Department of Energy reports consumption of diesel fuel and residual fuel oil by railroads.6 Average emission factors appli- cable to diesel fuel consumption were used to calculate emissions. The average sulfur content of each fuel was used to estimate S0X emissions. Coal consumption by railroads was obtained from References 7 and 13. 3.1.4 Vessels Vessel use of diesel fuel, residual oil, and coal is reported by the Department of Energy.6>7 Gasoline use is based on national boat and motor registrations, coupled with a use factor (gallons/motor/ year) from Reference 8 and marine gasoline sales as reported in Reference 4. Emission factors from AP-42? are used to compute emis- sions. Since AP-42 does not contain an emission factor for coal use by vessels, an average emission factor for coal combustion in boilers was used. 3.1.5 Nonhighway Use of Motor Fuels Gasoline and diesel fuel are consumed by off-highway vehicles. The fuel use is divided into seven categories; farm tractors, other farm machinery, construction equipment, industrial machinery, small general utility engines such as lawnmowers and snowthrowers, snowmobiles, and motorcycles. Fuel use is estimated for each category from estimated equipment population and an annual use factor of gallons per unit per year°, together with reported off-highway diesel fuel deliveries given in Reference 6 and off-highway gasoline sales reported in Reference 4. 3.2 Fuel Combustion in Stationary Sources 3.2.1 Coal Bituminous coal, lignite, and anthracite coal use are reported by the Department of Energy.Most coal is consumed by electric utilities. Average emission factors and the sulfur content of each type of coal were used to estimate emissions. Degree of particulate 35 ------- control was based on a report by Midwest Research Institute^ together with data from NEDSlO. Sulfur content data for electric utilities are available from the Department of Energyll. Sulfur contents for other categories are based on coal shipments data reported in Refer- ence 7 and average sulfur contents of coal shipped from each pro- duction district as reported in Reference 13 or 24. For electric utilities, SO2 emissions are adjusted to account for flue gas desul- furization controls, based on data reported in Reference 25. 3.2.2 Fuel Oil Distillate oil, residual oil, and kerosene are consumed by station- ary sources nationwide. Consumption by user category is reported by the Department of Energy.6 Average emission factors and the sulfur content of each fuel were used to estimate emissions. 3.2.3 Natural Gas Natural gas consumption data are also reported by the Department of Energy.12 Average emission factors from AP-42^ were used to calculate the emission estimates. 3.2.4 Other Fuels Consumption of wood has been estimated by the Department of Energy.27 Consumption of bagasse is based on data reported in NEDS.10 Sales of liquefied petroleum gas (LPG) are reported in Reference.6 Estimated consumption of coke and coke-oven gas are based on Reference 13 and 26, together with data from NEDS. Average emission factors were used to calculate emissions. Lead emissions from the combustion of waste oil were based on information obtained from Reference 32. The amount of waste oil burned has been assumed to remain constant and the emissions have been changed as a result of a decrease in the lead content of the waste oil. 3.3 Industrial Processes In addition to fuel combustion, certain other industrial processes generate and emit varying quantities of pollutants into the air. The lack of published national data on production, type of equipment, and controls, as well as an absence of emission factors, makes it impos- sible to include estimates of emissions from all industrial process sources. Production data for industries that produce the great majority of emissions were derived from literature data. Generally, the Minerals Yearbook,published by the Bureau of Mines, and Current Industrial Reports,14 published by the Bureau of the Census, provide adequate data for most industries. Average emission factors were applied to 36 ------- production data to obtain emissions. Control efficiencies applicable to various processes were estimated on the basis of published reports^ and from NEOS data.10 For the purposes of this report, petroleum product storage and marketing operations (gasoline, crude oil, and distillate fuel oil storage and transfer, gasoline bulk terminals and bulk plants, retail gasoline service stations) are included as industrial processes. Also included as industrial processes are industrial surface coating and degreasing operations, graphic arts (printing and publishing), and dry cleaning operations. All of these processes involve the use of organic solvents. Emissions from the consumption of organic solvents are estimated based on data reported in Reference 15. It is assumed that all solvents consumed are eventually released as air pollution, except for industrial surface coating operations. Esti- mates of the level of control for surface coating operations have been derived from References 10 and 28. In addition, the methodology given in Reference 15 has been updated to be consistent with similar procedures used for estimating organic solvent emissions in the National Emissions Data System (NEDS).29 3.3.1 Miscellaneous Industrial Processes for Lead Lead emissions from miscellaneous industrial processes include the major source of lead alkyl production as well as other minor sources such as type metal production, can soldering, cable covering, and other minor sources. The lead alkyl production is based on informa- tion from Reference 33. The production information for the other minor sources is from Reference 13. 3.4 Solid Waste Disposal A study conducted in 1968 on solid waste collection and disposal practices^ was the basis for estimating emissions from solid waste disposal. Results of this study indicate that the average collection rate of solid waste is about 5.5 pounds per capita per day in the United States. It has been stated that a conservative estimate of the total generation rate is 10 pounds per capita per day. The results of this survey were updated based on data reported in NEDS and used to estimate, by disposal method, the quantities of solid waste generated. Average emission factors were applied to these totals to obtain estimates of total emissions from the disposal of solid wastes. 3.5 Miscellaneous Sources 3.5.1 Forest Fires The Forest Service of the Department of Agriculture publishes infor- mation on the number of forest fires and the acreage burned.17 Esti- mates of the amount of material burned per acre are made to estimate 37 ------- the total amount of material burned. Similiar estimates are made to account for managed burning of forest areas. Average emission factors were applied to the quantities of materials burned to calculate emissions. 3.5.2 Agricultural Burning A studylS was conducted by EPA to obtain from local agricultural and pollution control agencies estimates of the number of acres and estimated quantity of material burned per acre in agricultural burning operations. These data have been updated and used to estimate agri- cultural burning emissions, based on average emission factors. 3.5.3 Coal Refuse Estimates of the number of burning coal-refuse piles existing in the United States are made in reports by the Bureau of Mines. 19 Their publication presents a detailed discussion of the nature, origin, and extent of this source of pollution. Rough estimates of the quantity of emissions were obtained using this information by applying average emission factors for coal combustion. It was assumed that the number of burning refuse piles decreased to a negligible amount by 1975. 3.5.4 Structural Fires The United States Department of Commerce publishes, in their statis- tical abstracts, information on the number and types of structures damaged by fire.20 Emissions were estimated by applying average emission factors for wood combustion to these totals. 3.5.5 Nonindustrial Organic Solvent Use This category includes nonindustrial sales of surface coatings (primarily for architectural coating) solvent evaporation from con- sumer products (aerosols, space deodorants, polishes, toiletries, etc.), use of volatile organic compounds as general cleaning solvents, paint removers, and liquefaction of asphalt paving compounds, and other undefined end uses. Total national organic solvent use is estimated from chemical production reports of Reference 21, together with estimates of the Dortion of total production for use as solvent for each chemical.15,29 it is assumed that all solvent production is equal to the amount necessary to make up for solvent lost through evaporation. 38 ------- 4. ANALYSIS OF TRENDS National trends in air pollutant emissions are a function of a number of factors. Air pollution control measures and economic conditions have the strongest impact on total emissions. National emission trends do not provide any insight into the distribution or concentration of air pollution sources within the United States. Therefore, local emission trends do not necessarily coincide with national emission trends. Based on the national implementation of control measures for some classes of sources, such as highway motor vehicles, it is reasonable to infer that for most localities, the national trend in emissions reasonably approximates local trends in emissions for the same class of sources. In addition to the fact that national emission trends do not measure local changes in emission densities, national emission trends may not be consistent with air quality trends because of the impact of meteorological factors on air quality data. Also, the estimates for PM, SOx, and NOx emissions include more substances than are routinely measured by ambient air monitoring equipment. For example, high-volume air samplers collect only suspended particulates approximately 0.3 to 100 micro-meters in diameter, but particulate emission inventories include both suspended and settled particulates generated by man's activities. Likewise, sulfur dioxide (SO2) and nitrogen dioxide (NO2) ambient air monitors measure only those two compounds while oxides of sulfur (SOx) and nitrogen (NOx) are included in the emission estimates. In each case, the substance measured by the ambient air monitor is the most prevalent constituent of its pollutant class or is acknowledged to be its most representative indicator. In this report, emissions of sulfur oxides are reported as the equivalent weight of SO2, which is the predominant sulfur oxide species. Some emissions of sulfur tri oxide (SO3) are also included, expressed at the equivalent weight of SO2. Similarly, nitrogen oxides include predominantly nitric oxide (NO) and nitrogen dioxide (NO2). Other nitrogen oxides are probably emitted in small amounts. In this report all nitrogen oxide emissions are express- ed as the equivalent weight of NO2. Estimates of oxidant emissions are not provided because most oxidant species are secondary pollutants generated by photochemical reactions in the atmosphere. Emission estimates of VOC, a major ingredient in oxidant-producing reactions, were developed from current emission factors.2,3 Generally excluded from VOC estimates were emissions of methane, ethane, methyl chloroform, and other compounds which are considered to be of neglible photochemical reactivity. Organic species were identified based on Reference 22. If no data were available for a source category, the total nonmethane hydro- carbon or the total hydrocarbon emission factor from Reference 2 was used. Highway vehicle emissions were estimated as nonmethane VOC's.3 The following sections discuss the most important factors influencing the emission trends for each pollutant. 39 ------- 4.1 Particulates 1940-1970 The estimated particulate emissions for 1940, 1950 and 1960 are 15 to 30 percent higher than in 1970. Even though industrial production levels and the quantities of fuels consumed were lower than the post- 1970 period, the general lack of air pollution controls before 1970 resulted in relatively large particulate emissions. Also, for the years 1940 and 1950, particulate emissions from coal combustion by railroads and from forest wildfires were significant. A large portion of the particulate emissions from stationary source fuel combustion, result from the combustion of coal. In 1940, coal was consumed largely in the industrial and residential sectors. Residential coal use has declined substantially since 1940, resulting in a corre- sponding reduction in emissions. Industrial coal use has also declined, but not to the same extent. The degree of control employed by industrial coal consumers has increased, however, so that overall industrial coal combustion emissions decreased by 1970 to only about 40 percent of the estimated 1940 level. On the other hand, coal combustion by electric utilities has increased greatly, from an estimated 51 million tons in 1940 to 321 million tons in 1970. This increased consumption resulted in increased emissions from 1940 to 1950. Since then, particulate emis- sions from electric utilities have decreased, despite continued in- creases in coal consumption. Installation of improved control equip- ment is responsible for this reduction. Particulate emissions from industrial processes increased from 1940 to 1950, reflecting increased industrial production. From 1950 to 1970, industrial output continued to grow, but installation of pollution control equipment helped to offset the increase in industrial produc- tion. As a result, from 1950 to 1960 industrial process emissions stayed about the same, and decreased slightly from 1960 to 1970. 1970-1983 Since 1970, particulate emissions have decreased substantially as the result of air pollution control efforts. The extent of the reduction is most evident from the data in Table 29 which shows theoretical 1983 national emission estimates, assuming that pollutant control levels did not change since 1970. Overall, particulate emissions would have increased by about 7 percent from 1970 to 1983 with no change in the degree of control from 1970. In comparison, as shown in Table 1, particulate emissions decreased about 62 percent from 1970 to 1983. Thus, 1983 actual particulate emissions were about a third of what they might have been without additional control efforts since 1970. A large portion of the particulate emissions from stationary source fuel combustion result from the combustion of coal. In 1970, a larger portion of coal was consumed in the industrial and residential sectors. 40 ------- Residential coal use has declined substantially since 1970, resulting in a corresponding reduction in emissions. Industrial coal use has also declined, but not to the same extent. The degree of control employed by industrial coal consumers has increased, however, so that overall industrial coal combustion emissions have decreased by 1983 to only about 16 percent of the estimated 1970 level. On the other hand, coal combustion by electric utilities has increased greatly, from an estimated 321 million tons in 1970 to 625 million tons in 1983. However, particulate emissions from electric utilities have decreased, despite continued increases in coal consumption. Installation of improved control equipment is responsible for this reduction. New facilities constructed in the 1970's were required to meet New Source Performance Standards (NSPS) requirements to achieve a high degree of control. From Tables 2 and 29, it can be seen that if the 1970 level of control had remained in effect in 1983, electric utility emissions would have nearly doubled, from 2.3 teragrams to 4.6 teragrams. Estimated actual 1983 emissions from electric utilities were 0.5 teragrams, a decrease of 78 percent from 1970. Particulate emissions from industrial processes have been reduced substantially due to installation of improved control equipment mandated by air pollution control programs. Since 1970, actual emissions from industrial processes declined by over 77 percent. If the 1970 control level had remained unchanged to 1983, emissions would have decreased only about 14 percent. It should be noted that industrial production levels for many sectors in 1983 were significantly lower than in the previous few years, reflecting poor economic conditions. This down-turn in industrial production also contributes to a decreased level of emissions relative to 1970. Table 23 shows estimated emissions for specific processes. These annual emissions estimates reflect changes in production levels along with an increase in average control levels from 1970 to 1983. Comments on Particulate Emission Estimates Caveats that should be noted with respect to these particulate emission estimates are first that the estimates represent total particu- late emissions, without any distinction of particle sizes. Thus, both large particles and small particles are included. Emissions of very large particles are more likely to settle out of the atmosphere and not be measured as total suspended particulate by air quality monitoring equipment. Small and intermediate size particles are more likely to remain airborne and are more efficiently captured by total suspended particulate air monitoring equipment. Small particles are also capable of being inhaled into the human respiratory system, possibly causing adverse health effects. The particulate emission controls that have been employed to date have been most effective in reducing emissions of large and intermediate size particles. The trend in the emissions of small particles is not clearly known. It is very doubtful whether small particle emissions have been reduced to the extent that total particulate emissions have been reduced, however. It should be noted 41 ------- that some small particles may be formed in the atmosphere as the result of various chemical and physical processes. Such particles are not included in the estimated total particulate emissions. A second caveat is that fugitive particulate (emissions from unconfined sources such as storage piles, material loading, etc.) emissions are incompletely ac- counted for in the emission totals. Rough estimates of industrial pro- cess fugitive emissions are included for some industries. Area source fugitive dust emissions (unpaved roads, construction activities, etc.) are not included at all. Similarly, natural sources of particulates, such as wind erosion or dust, are not included. (An exception is forest fires, some of which result from natural causes). In total, these fugitive emissions may amount to a considerable portion of total particulate emissions. The controls applied to these sources have so far been minimal. Due to the lack of adequate emission factors and emission inventory techniques for these sources, fugitive particulate emissions have not been included in most emission inventories. As additional data become available, it is expected that estimates of fugitive particulate emissions will be included in future emission inventories. It should be noted, however, that a major portion of the fugitive particulate emissions are relatively large particles that are not readily captured by particulate air quality monitors. Simi- larly, these large particles do not effectively enter into the human respiratory system. 4.2 Sulfur Oxides 1940-1970 From 1940 to 1970, major increases in sulfur oxide emissions occurred as the result of increased combustion of fossil fuels such as coal and oil. Industrial process emissions also increased, but to a lesser extent. Sulfur oxide emissions from other source categories decreased, primarily as the result of the obsolescence of coal-fired railroad locomotives and a decrease in coal refuse burning. 1970-1983 Since 1970, total sulfur oxide emissions have declined about 26 percent as the result of use of fuels with lower average sulfur contents, some scrubbing of sulfur oxides from flue gases, and controls on indus- trial process sources. Significant emission reductions from industrial processes have occurred, mostly from non-ferrous smelters and sulfuric acid plants. By-product recovery of sulfuric acid at smelters has increased since 1970. As a result, sulfur oxide emissions that previ- ously would have been released to the atmosphere are recovered as sulfuric acid. Since 1972, new sulfuric acid manufacturing plants have been subject to New Source Performance Standards requirements. These rules have contributed to decreased emissions, as new plants built to meet new product demands or replace old facilities, must meet more stringent emission limitations than old facilities. 42 ------- As shown in the tables, since 1970 sulfur oxide emissions from electric utilities account for more than half of the total emissions. Combustion of sulfur-bearing fuels, chiefly coal and residual fuel oil, is responsible. Between 1970 and 1983, utility use of coal increased by about 95 percent. Emissions from utilities have decreased, however, because fuels with lower sulfur content have been used to the extent that they were available. Also, flue gas desulfurization systems have been installed so that by the late 1970's enough units were in service to prevent increases in electric utility emissions. 1983 electric utility emissions would have been approximately 15 percent higher without the operation of flue gas desulfurization controls. The theoretical 1983 national emission estimates given in Table 29 for stationary fuel combustion sources are based on 1983 fuel amounts but fuel sulfur contents that represent 1970 average levels for fuel oil and an estimated average sulfur content of coal that would have been consumed if there were no changes in air pollution regulations since 1970. It is estimated that the national average sulfur content of coal burned would have declined anyway even without new air pollution regulations due to the greater use of coal from the Western U.S., which generally has a lower sulfur content than coal from the Eastern States. On this basis, electric utility emissions would have increased 24 percent. In fact, emissions decreased by 11 percent. Sulfur oxide emissions from other fuel combustion sectors decreased, primarily due to less coal burning by these industrial, commercial and residential consumers. Comments on Sulfur Oxide Emission Estimates Emissions of sulfur and nitrogen oxides have been identified as precursors of acidic precipitation and deposition. To support Federal research activities on the subject, more detailed historical emissions estimates of sulfur and nitrogen oxides have been developed. Interested readers may wish to review Reference 30, which contains State level estimates of sulfur and nitrogen oxide emissions from 1900 through 1980. 4.3 Nitrogen Oxides 1940-1970 Nitrogen oxide emissions result almost entirely from fuel combustion by stationary sources and motor vehicles. From 1940 through 1970, NOx emissions increased steadily as the result of increased fuel combustion. 1970-1983 Controls applied to sources of NOx emissions have had a limited effect in reducing emissions through 1983. Table 29 shows that with the 1970 control level, national NOx emissions would have been only 18 percent higher than actual 1983 emissions. The emissions from stationary fuel 43 ------- combustion sources largely reflect the actual growth in fuel consump- tion. For electric utilities, NSPS control requirements have held down the growth in NOx emissions somewhat. Nevertheless, NOx emissions from electric utilities increased 40 percent from 1970 to 1983. For mobile sources, NOx emissions were controlled as a result of the Federal Motor Vehicle Control Program (FMVCP). Nitrogen oxide emissions from highway vehicles would have increased 57 percent, had there been no change in control level since 1970. The estimates of actual NOx emissions show a 17 percent increase. 4.4 Volatile Organic Compounds 1940-1970 From 1940 through 1970, VOC emissions increased about 50 percent. Major increases in highway vehicle travel and industrial production were chiefly responsible. Emissions from these source categories were about two and a half times higher in 1970 than in 1940. Emissions from residential fuel combustion and forest fires declined substantially, however. In 1940, residential fuel combustion and forest fires account- ed for 40 percent of total national VOC emissions. By 1970, their contribution to total VOC emissions had been reduced to 6 percent. 1970-1983 Since 1970, emissions of VOC decreased primarily due to motor vehicle controls and less burning of solid waste. Had controls not been implemented, a substantial increase in emissions from highway vehicles would have occurred. From 1970 to 1983, vehicle-miles of travel in the U.S. increased by about 47 percent.°> A comparable increase in emissions would have occurred had 1970 control levels remained unchanged. As a result of the controls put in place, VOC emissions from highway vehicles actually decreased 46 percent. VOC emissions also decreased due to the substitution of water-based emulsified asphalts (used for road paving) for asphalts liquefied with petroleum distillates (cutback asphalts). This is reflected in the decreased emissions reported for miscellaneous organic solvent use. Through 1978 these decreases were offset by increases in industrial process emissions. Since then, industrial process emissions have also declined, so that overall total VOC emissions were reduced about 26 percent from 1970 to 1983. Industrial process emissions increased due to higher production levels, particularly in industrial sectors such as petroleum refining, organic chemical production, and industrial uses of organic solvents. Control procedures employed were effective in limiting the growth in emissions, however. In addition, source production levels in 1980 through 1983 were relatively low due to poor economic conditions. Through the mid-1970's, emissions from petroleum product storage and marketing operations also increased as the result of increased demand for petroleum products, particularly motor gasoline. 44 ------- Since 1978, emissions from this source sector are estimated to have decreased as the result of declining product demand and more effective control measures. In 1970, VOC emissions from residential fuel combustion were insigni- ficant. However, in the late 19701s emissions began to increase due to the popularity of wood stoves and fireplaces for residential space heating. In 1983, residential fuel combustion accounted for about 10 percent of total VOC emissions. Comments on VOC Emission Estimates Volatile organic compounds along with nitrogen oxides are participants in atmospheric chemical and physical processes that result in the formation of ozone and other photochemical oxidants. Emissions of VOC that are most likely to have a role in such atmospheric processes are included in the reported emissions estimates. Photochemically non- reactive compounds such as methane are not included in the estimated emissions of VOC. Biogenic sources of organic compounds such as trees and other vegetation are not included either. Initial estimates are that emissions of VOC from naturally-occurring sources exceed the amount of anthropogenic emissions. The extent to which biogenic sources of VOC contribute to oxidant formation, if at all, has not been clearly estab- lished, however. Ambient concentrations of ozone are typically higher during the summer months. As a result, analysis of seasonal, rather than annual VOC emissions may be more appropriate to understand the relationship between VOC emissions and high ozone concentrations in the atmosphere. Sources such as residential space heating, which occurs primarily during the winter would have little impact on summer ozone levels. 4.5 Carbon Monoxide 1940-1970 From 1940 through 1970, the relative contribution by the various source categories to total CO emissions changed considerably. In 1940, highway vehicles contributed only about 28 percent of carbon monoxide emissions. Residential fuel combustion (primarily of wood and coal), forest fires and other burning (agricultural crop residues and coal refuse) contributed about 50 percent of total CO emissions. From 1940 to 1970, highway vehicle emissions nearly tripled, while emissions from residential fuel combustion and miscellaneous burning sources decresed substantially. As a result, in 1970 highway vehicles accounted for 64 percent of total CO emissions. Industrial process CO emissions increas- ed from 1940 to 1970 by about 36 percent. The largest increase occurred in the petroleum refining sector, primarily as the result of expansion of catalytic cracking capacity to meet increased demand for gasoline and other middle distillates. 45 ------- 1970-1983 Since 1970, highway motor vehicles have been the largest contributing source of CO emissions. The implementation of the Federal Motor Vehicle Control Program (FMVCP) has been successful in reducing CO emissions since the early 1970's. From 1970 through 1978, motor vehicle miles of travel increased 38 percent, but because of controls on new vehicles, total CO emissions from highway vehicles decreased 16 percent. From 1978 to 1980, VMT declined by 1.7 percent. Since 1980, growth in VMT has resumed, similar to the growth rate that occurred in the 1970's. Overall, from 1978 to 1983, VMT grew by only 6.5 percent, however. This lack of growth in vehicle travel together with an increased degree of control because of stricter emission standards for new vehicles and the gradual disappearance of older uncontrolled vehicles from the vehicle fleet, produced an estimated 22 percent drop in highway vehicle emissions in the four year period from 1978 to 1982. Overall from 1970 to 1983, without the implementation of FMVCP, highway vehicle emissions would have increased 34 percent. By comparison, actual emissions are estimated to have decreased 34 percent. CO emissions from other sources have also generally decreased. In 1970, emissions from burning of agricultural crop residues were greater than in more recent years. Solid waste disposal emissions have also decreased as the result of implementation of regulations limiting or prohibiting burning of solid waste in many areas. Emissions of CO from stationary source fuel combustion occur mainly from the residential sector. These emissions were reduced somewhat through the mid-1970's as residential consumers converted to natural gas, oil, or electric heating equipment. Recent growth in the use of residential wood stoves has reversed this trend, but increased CO emissions from residential sources continue to be small compared to highway vehicle emissions. Nevertheless, in 1983 residential wood combustion accounted for about 9 percent of national CO emissions, more than any source category except highway vehicles. CO emissions from industrial processes have generally been declining since 1970 as the result of the obsolescence of a few high polluting processes such as manufacture of carbon black by the channel process and installation of controls on other processes. 4.6 Lead 1970-1983 The emissions of lead have decreased due to the implementation of the Federal Motor Vehicle Control Program (FMVCP). The implementation of FMVCP has resulted in the use of catalytic converters to reduce NOx, V0C, and CO emissions and has required the use of unleaded gasoline for vehicles with converters. From 1970 through 1974, the highway use of gasoline increased 13 percent, but because of the decrease in lead content in leaded gasoline, lead emissions from highway vehicles decreased 17 percent. From 1975 to 1983, the percent unleaded gasoline 46 ------- sales increased from 13 to 55 percent, and the lead emissions decreased 67 percent. From 1970 through 1983, off highway consumption of gasoline decreased 44 percent while lead emissions decreased 74 percent. Lead emissions also decreased from other sources. The 94 percent decrease in stationary source fuel combustion is a result of the decrease in lead concentration in waste oil utilized in industrial boilers. Lead emissions decreased 90 percent for industrial processes from 1970 through 1983. Part of this decrease reflects the changes that result from installation of air pollution control equipment. As shown in Tables 12 and 29, the change in emissions as a result of changes in operating rates would be a 32 percent reduction. Lead emissions from solid waste disposal have decreased 84 percent from 1970 through 1983 as a result of the decreased amount of solid waste disposed of by i nci neration. 47 ------- TABLE 29 THEORETICAL 1983 NATIONAL EMISSION ESTIMATES BASED ON 1970 LEVEL OF CONTROL (TERAGRAMS/YEAR) Source Category PM SO, NO. voc CO P81 Transportation Highway Vehicles 1.4 0.5 9.4 15.7 83.9 181.2 Non-Highway 0.2 0.4 1.8 1.2 6.6 4.3 Transportation Total 1.6 0.9 11.2 16.9 90.5 185.5 Stationary Source Fuel Combustion Electric Utilities 4.6 19.6 7.1 0.0 0.3 0.5 Industrial 1.1 2.1 2.8 0.1 0.6 9.2 Residential/Commercial 1.1 0.7 0.6 2.0 6.1 0.0 Fuel Combustion Total 6.8 22.4 10.5 2.1 7.0 9.7 Industrial Processes (SIC) Mining Operations (10,2,13,14) 3.3 0.4 0.0 0.0 0.0 0.2 Food and Agriculture (02,07,20) 0.9 0.0 0.0 0.2 0.0 0.0 Wood Products (24,26) 0.7 0.1 0.0 0.0 0.7 0.0 Chemicals (28) 0.2 0.7 0.2 2.0 2.4 0.4 Petroleum Refining (29) 0.1 0.9 0.2 1.0 2.0 0.0 Mineral Products (32) 2.4 0.7 0.2 0.0 0.0 0.5 Metals (33) 1.1 2.5 0.0 0.0 2.2 15.1 Miscellaneous 0.0 0.0 0.0 5.8 0.0 0.1 Industrial Processes Total 8.7 5.3 0.6 9.0 7.3 16.3 Solid Waste 1.2 0.1 0.4 2.0 7.0 3.3 Miscellaneous 0.9 0.0 0.2 3.3 6.3 0.0 Total 19.2 28.7 22.9 33.3 118.1 214.8 1983 Actual Emissions (Table 1) 6.9 20,8 19.4 19.9 67.6 46.9 Theoretical 1983 Emissions As A 278S 138* 118$ 1672 1751 4581 Percentage Of 1983 Actual Emissions 1970 Actual Emissions (Table 1) 18.0 28.2 18.1 27.0 98.3 203.8 Theoretical 1983 Emissions As A 107* 102S 127? 1232 1201 105* Percentage of 1970 Actual Emissions *Lead emissions are expressed in g1gagrams/yea r. 48 ------- 5. REFERENCES *1. National Emissions Report, National Emissions Data System (NEDS). NADB, OAQPS, US Environmental Protection Agency, Research Triangle Park, NC. Publication No. EPA-450/4-84-026. November 1984. 2. Compilation of Air Pollutant Emission Factors, Third Edition (Including Supplements 1-15). US Environmental Protection Agency, Research Triangle Park, NC. Publication No. AP-42. 3. User's Guide to M0BILE3 (Mobile Source Emissions Model K US Envi- ronmental Protection Agency, Office of Mobile Source Air Pollution Control, Ann Arbor, Michigan. Publication No. EPA-460/3-89-002. June 1984. *4. Highway Statistics. Federal Highway Administration, US Department of Transportation, Washington, DC. 1983. *5. FAA Air Traffic Activity. Federal Aviation Administration, US Department of Transportation, Washington, DC. 1983. *6. Petroleum Supply Annual 1983, Energy Information Administration, US Department of Energy. Washington, DC. Publication No. DOE/EIA- 0 340(83)/1. June 1984. *7. Coal Distribution January-December, Energy Information Administration, US Department of Energy, Washington, DC. Publication No. DOE/EIA- 0125(83/4Q). April 1984. 8. Exhaust Emissions from Uncontrolled Vehicles and Related Equipment Using Internal Combustion Engines. Southwest Research Institute, San Antonio, TX. Prepared for US Environmental Protection Agency, Research Triangle Park, NC. EPA Contract No. EHS 70-108. Oct 1973. 9. Particulate Pollutant Systems Study. Midwest Research Institute, Kansas City, MO. Prepared for US Environmental Protection Agency, Research Triangle Park, NC. National Air Pollution Control Administration Contract No. CPA 22-69-104. May 1971. 10. Standard Computer Retrievals from the National Emissions Data System (NEDS). Unpublished computer report available from NADB, OAQPS, US Environmental Protection Agency, Research Triangle Park, NC. *These publications are issued periodically. The most recent publication available when this document was prepared is cited. 49 ------- *11. Cost and Quality of Fuels for Electric Utility Plants-1983, Energy Information Administration, US Department of Energy, Washington, D.C. Publication No. D0E/EIA-0191(83). July 1984. *12. Natural Gas Annual, Energy Information Administration, US Department of Energy, Washington, DC. Publication No. D0E/EIA-0131(82). October 1983. *13. Minerals Yearbook. Bureau of Mines, US Department of the Interior, Washington, DC. 1982. *14. Current Industrial Reports. Bureau of the Census, US Department of Commerce, Washington, DC. 15. End Uses of Solvents Containing Volatile Organic Compounds, The Research Corporation of New England, Wethersfield, CT, EPA Publication EPA-450/3-79-032, May 1979. 16. 1968 National Survey of Community Solid Waste Practices. Public Health Service, US Department of Health, Education, and Welfare, Cincinnati, OH. PHS Publication No. 1867. 1968. *17. Wildfire Statistics. Forest Service, US Department of Agriculture, Washington, DC. 1978. 18. Emissions Inventory from Forest Wildfires, Forest Managed Burns, and Agricultural Burns. US Environmental Protection Agency, Research Triangle Park, NC 27711. Publication No. EPA-450/3-74- 062. November 1974. 19. Coal Refuse Fires, An Environmental Hazard. Bureau of Mines, US Department of the Interior, Washington, DC. Information Circular 8515. 1971. *20. Statistical Abstract of the United States. Bureau of the Census, US Department of Commerce, Washington, DC. 1984 (104th ed.). *21. Chemical and Engineering News, Annual Facts and Figures Issue, American Chemical Society, Washington, DC. June 11, 1984. 22. Volatile Organic Compound (VOC) Species Data Manual Second Edition, US Environmental Protection Agency, Research Triangle Park, NC. Publication No. EPA-450/4-80-015. July 1980. 23. Standard Industrial Classification Manual 1972, Executive Office of the President, Office of Management and Budget, Washington, DC. *These publications are issued periodically. The most recent publication available when this document was prepared is cited. 50 ------- *24. Coal Production, Energy Information Administration, US Department of Energy, Washington, DC. Publication No. D0E/EIA-0118(83). October 1984. *25. Project Summary Utility FGD Survey April-June 1983. PEDCo Environmental, Inc., Cincinnati, OH. Prepared for Electric Power Research Institute, Contract No. RP982-32. October 1983. *26. Quarterly Coal Report, Energy Information Administration, U.S. Department of Energy, Washington, DC. Publication No. DOE/EIA- 0121(84/2Q). September 1984. 27. Estimates of U.S. Wood Energy Consumption from 1949 to 1981. U.S. Department of Energy, Washington, DC. Publication No. DOE/EIA- 0341. August 1982. 28. Organic Solvent Use in Web Coating Operations, Emission Standards and Engineering Division, US Environmental Protection Agency, Research Triangle Park, NC. Publication No. EPA-450/3-81-012. September 1981. 29. AEROS Manual Series Volume IV: NADB Internal Operations Manual. OAQPS Guidelines No. 1.2-041. U.S. Environmental Protection Agency, Research Triangle Park, NC. January 1978. 30. Historic Emissions of Sulfur and Nitrogen Oxides in the United States from 1900 to 1980. Pacific Environmental Services, Inc. Durham, NC. Prepared under EPA Contract 68-02-3511, Task No. 31 and 47. November 1984. 31. Supplementary Guidelines for Lead Implementation Plans--Updated Projections for Motor Vehicle Lead Emissions, OAQPS/OMS Research Triangle Park, NC 27711/Ann Arbor, MI 48105. Publication No. EPA-450/2-83-002. March 1983. 32. Telephone communication between Jacob Summers, OAQPS, and Michael Petruska, Office of Solid Waste, US EPA, Washington, DC, November 9, 1984. *33. Synthetic Organic Chemicals, United States Production Sales, 1983, United States International Trade Commission, Washington, DC 20436. *These publications are issued periodically. The most recent publication available when this document was prepared is cited. 51 ------- TECHNICAL REPORT DATA (Please read Instructions on the reverse before completing) 1. REPORT NO. 2. EPA-450/4-84-028 3. RECIPIENT S ACCESSION NO. 4. TITLE AND SUBTITLE National A1r Pollutant Emission Estimates, 1940-1983 5. REPORT DATE December 1984 6. PERFORMING ORGANIZATION CODE 7. AUTHOR(S) Monitoring and Data Analysis Division 8. PERFORMING ORGANIZATION REPORT NO. 9. PERFORMING ORGANIZATION NAME AND ADDRESS U.S. Environmental Protection Agency Office of A1r and Radiation Office of A1r Quality Planning and Standards Research Triangle Park, North Carolina 27711 10. PROGRAM ELEMENT NO. 11. CONTRACT/GRANT NO. 12. SPONSORING AGENCY NAME AND ADDRESS 13. TYPE OF REPORT AND PERIOD COVERED Final - 1940-1983 14. SPONSORING AGENCY CODE 16. SUPPLEMENTARY NOTES 16. ABSTRACT This report presents estimates of trends 1n nationwide air pollutant emissions for the six major pollutants: sulfur oxides, particulates, carbon monoxide, volatile organic compounds, nitrogen oxides, and lead. Estimates are broken down according to major types of air pollutant sources. A short analysis of emission trends 1s given, along with a discussion of methods used to develop the data. 17. KEY WORDS AND DOCUMENT ANALYSIS a. DESCRIPTORS b.IDENTIFIERS/OPEN ENDED TERMS c. COSATI Field/Group trends, emissions, inventory, air pollutants, nationwide, sulfur oxides, carbon monoxide, particulates, volatile organic compounds, nitrogen oxides, con- trollable emissions, miscellaneous sources, lead 18. DISTRIBUTION STATEMENT Release unlimited 19. SECURITY CLASS (This Report) Unclassified 21. NO. OF PAGES 53 20. SECURITY CLASS (This page) Unclassified 22. PRICE EPA Form 2220-1 (Rev. 4-77) previous edition is obsolete ------- INSTRUCTIONS 1. REPORT NUMBER Insert the LPA report number as jt appears on the cover of the publication. 2. LEAVE BLANK 3. RECIPIENTS ACCESSION NUMBER Reserved for use by each report recipient. 4. TITLE AND SUBTITLE Title should indicate clearly and briefly the subject coverage of the report, and be displayed prominently. Set subtitle, if used, in smaller type or otherwise subordinate it to main title. When a report is prepared in more than one volume, repeal the primary title, add volume number and include subtitle for the specific title. 5. REPORT OATE Each report shall carry a date indicating at least month and year. Indicate the basis on which it was selected (c.jr., date of issue. datc'of ' approval, date of preparation, etc.). 6. PERFORMING ORGANIZATION CODE Leave blank. 7. AUTHOR(S) Give name(s) in conventional order (John R. Doc, J. Robert Doe, etc.). List author's affiliation if it differs from the performing organi- zation. 8. PERFORMING ORGANIZATION REPORT NUMBER Insert if performing organization wishes to assign this number. 9. PERFORMING ORGANIZATION NAME ANOADORESS Give name, street, city, state, and ZIP code. List no more than two levels of an organizational liircarchy. 10. PROGRAM ELEMENT NUMBER Use the program element number under which the report was prepared. Subordinate numbers may be included in parentheses. 11. CONTRACT/GRANT NUMBER Insert contract or grant number under which report was prepared. 12. SPONSORING AGENCY NAME AND AODRESS Include ZIP code. 13. TYPE OF REPORT ANO PERIOO COVEREO Indicate interim final, etc., and if applicable, dates covered. 14. SPONSORING AGfcNCY COOE Insert appropriate code. 16. SUPPLEMENTARY NOTES Enter information not included elsewhere but useful, such as: Prepared in cooperation with. Translation of, Presented al coiiIitcikc <>f. To be published in. Supersedes, Supplements, etc. 16. ABSTRACT Include a brief (200 words or less) factual summary of the most significant information contained in the report. If die report contains a significant bibliography or literature survey, mention it here. 17. KEY WORDS AND DOCUMENT ANALYSIS (a) DESCRIPTORS - Select from the Thesaurus of Engineering and Scientific Terms the proper authorized terms that identify the major concept of the research and are sufficiently specific and precise to be used as index entries for cataloging. (b) IDENTIFIERS AND OPEN-ENDED TERMS - Use identifiers for project names, code names, equipment designators, etc. Use open- ended terms written in descriptor form for those subjects for which no descriptor exists. (c) COSAT1 FIELD GROUP - Field and group assignments are to be taken from the 1965 COSATI Subject Category List. Since the ma- jority of documents are multidisciplinary in nature, the Primary Field/Group assignmcnt(s) will be specific discipline, area of human endeavor, or type of physical object. The application(s) will be cross-refcrcnccd with secondary Field/Group assignments that will follow the primary posting(s). 18. DISTRIBUTION STATEMENT Denote releasability to the public or limitation for reasons other than security for example "Release Unlimited." Cite any availability to the public, with address and price. 19. &20. SECURITY CLASSIFICATION DO NOT submit classified reports to the National Technical Information service. 21. NUMBER OF PAGES Insert the total number of pages, including this one and unnumbered pages, but exclude distribution list, it any. 22. PRICE Insert the price set by the National Technical Information Service or the Government Printing Office, if known. EPA Form 2220—1 (Rev. 4—77) (Reverie) ------- |