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California Air Resources Board
Development of Emission Development of Emission Inventories for Inventories for
Air Quality PlansAir Quality Plans
Development of Emission Development of Emission Inventories for Inventories for
Air Quality PlansAir Quality Plans
Bart E. Croes, P.E.Bart E. Croes, P.E.Chief of the Research DivisionChief of the Research DivisionCalifornia Air Resources BoardCalifornia Air Resources Board
Delhi, IndiaDelhi, IndiaNovember 6-11, 2000November 6-11, 2000
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2California Air Resources Board
Presentation OutlinePresentation Outline
I.I. OverviewOverview
II.II. California’s EmissionCalifornia’s EmissionInventory ProgramInventory Program
III.III. Planning for Planning for EmissionEmissionInventoriesInventories
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Clean Air
Air Quality MonitoringAir Quality Monitoring
Emission InventoryEmission Inventory
Air Quality Air Quality ModelingModeling
ControlControlStrategyStrategy
Building an Air Quality PlanBuilding an Air Quality Plan
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4California Air Resources Board
Emission InventoryEmission Inventory
““Is a comprehensive listing of Is a comprehensive listing of the sources of air pollution the sources of air pollution andand an an estimateestimate of their of their emissions within a specific emissions within a specific geographic area for a geographic area for a specific time interval.”specific time interval.”
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5California Air Resources Board
Inventories can be used to:Inventories can be used to: Identify sources of pollutionIdentify sources of pollution Identify pollutants of concernIdentify pollutants of concern Amount, distribution, trends Amount, distribution, trends Identify and track control strategiesIdentify and track control strategies Input to air quality modelingInput to air quality modeling Input to health risk assessmentInput to health risk assessment
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6California Air Resources Board
Types of InventoriesTypes of Inventories
Annual averageAnnual average
Seasonal inventoriesSeasonal inventories
Forecasted - future estimatesForecasted - future estimates
Gridded / ModelingGridded / Modeling
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7California Air Resources Board
Pollutants:Pollutants:CriteriaCriteria
TOGTOG - - total organic gasestotal organic gases
ROGROG - - reactive organic gasesreactive organic gases
COCO - - carbon monoxidecarbon monoxide
NONOxx - - oxides of nitrogenoxides of nitrogen
SOSOxx - - oxides of sulfuroxides of sulfur
PMPM - - particulate matterparticulate matter
PMPM1010 - - PM PM << 10 microns 10 microns
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8California Air Resources Board
Pollutants:Pollutants:ToxicsToxics
Diesel PMDiesel PM BenzeneBenzene 1,3-Butadiene1,3-Butadiene FormaldehydeFormaldehyde Hexavalent ChromiumHexavalent Chromium PerchloroethlyenePerchloroethlyene LeadLead
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StationaryStationarySourcesSources RefineriesRefineries
ManufacturingManufacturing
Food processingFood processing
Electric utilitiesElectric utilities
Chemical Chemical productionproduction
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Area-WideArea-WideSourcesSources
FarmingFarming Paved & unpavedPaved & unpaved
road dustroad dust SolventsSolvents ConsumerConsumer
productsproducts Open burningOpen burning
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Mobile SourcesMobile Sources CarsCars
TrucksTrucks
BusesBuses
AircraftAircraft
TrainsTrains
ShipsShips
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Non- anthropogenicNon- anthropogenic
WildfiresWildfires
BiogenicsBiogenics
Windblown DustWindblown Dust
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13California Air Resources Board
California’sCalifornia’sEmissionEmissionInventoryInventoryProgramProgram
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14California Air Resources Board
California’s Emission California’s Emission Inventory ProgramInventory Program
Required by State lawRequired by State law Over 30 years of experienceOver 30 years of experience Cooperative effort with other Cooperative effort with other
agencies agencies (state, federal, local)(state, federal, local)
Cooperation with industry groupsCooperation with industry groups Commitment of resourcesCommitment of resources
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15California Air Resources Board
California ProcessCalifornia Process
Local Districts - facility dataLocal Districts - facility data
State - on-road and off-road State - on-road and off-road emissionsemissions
Both share area-wide categoriesBoth share area-wide categories
Other agencies also provide dataOther agencies also provide data
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16California Air Resources Board
California’s InventoryCalifornia’s Inventory
Comprehensive inventoryComprehensive inventory
Data base 1979-1999Data base 1979-1999
Forecasts to 2020Forecasts to 2020
Criteria and toxics Criteria and toxics
Over 800 categories of emissionsOver 800 categories of emissions
Over 12,000 stationary sourcesOver 12,000 stationary sources
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17California Air Resources Board
Inventory ImprovementsInventory Improvements Ongoing researchOngoing research
Category improvements to support Category improvements to support regulationsregulations
Intense studies every 3-4 years to Intense studies every 3-4 years to support planning processsupport planning process
Published annually Published annually
Incorporate new improvementsIncorporate new improvements
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18California Air Resources Board
Statewide ChangesStatewide ChangesROG for 1995ROG for 1995
0
500
1000
1500
2000
2500
3000
3500
4000
Stationary Area On-RoadMobile
OtherMobile
Total
1995 Estimate
2000 Estimate
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19California Air Resources Board
Statewide ChangesStatewide ChangesNONOxx for 1995 for 1995
0
500
1000
1500
2000
2500
3000
3500
4000
4500
Stationary Area On-RoadMobile
OtherMobile
Total
1995 Estimate
2000 Estimate
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Passenger Car Emissions Passenger Car Emissions Changes for Southern CaliforniaChanges for Southern California
Year 2000, by Emissions ModelYear 2000, by Emissions Model
0
50
100
150
200
250
300
350
TOG CO NOx PM10
7E
7F
7G
2K
ton
s/d
ay
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21California Air Resources Board
Consumer ProductsConsumer ProductsSouthern California, 1997Southern California, 1997
0
50
100
150
200
250
300
350
ton
s/d
ay
ROG
1982 Study
1995 Survey
1997 Survey
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Southern California Southern California NONOxx, ROG, PM, ROG, PM1010
Stationary11%
Area-wide3%
On-road65%
Other Mobile
21%
NONOxx
Stationary23%
Area-wide16%
On-road51%
Other Mobile
10%
ROGROG
Stationary7%
Area-wide84%
On-road6%
Other Mobile
3%
PMPM1010
Source: 1999 California Almanac of Emissions & Air Quality, ARB
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19851990
1995
0
400
800
1200
1600
2000
Em
issi
on
s (t
on
s p
er d
ay)
Stationary Area-wide Gasoline Vehicles
Diesel Vehicles Other Mobile
19851990
1995
0
400
800
Em
issi
ons
(ton
s pe
r d
ay)
Stationary Area-wide Gasoline VehiclesDiesel Vehicles Other Mobile
19851990
1995
0
400
800
1200
1600
Em
issi
on
s (t
on
s p
er d
ay)
Stationary Area-wide Gasoline VehiclesDiesel Vehicles Other Mobile
Southern California Trends Southern California Trends NONOxx, ROG, PM, ROG, PM1010
NONOxx
ROGROG
PMPM1010
Source: 1999 California Almanac of Emissions & Air Quality, ARB
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Air Quality Improvement Air Quality Improvement versus Growthversus Growth
-50 -47 -30
+41 +81 +75
-60
-40
-20
0
20
40
60
80
Per
cen
t Ch
ang
e19
80-1
998
Ozone PM10 Toxics Population VehicleTravel
Economy
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25California Air Resources Board
Resource Commitment Resource Commitment
Over 50 people at State levelOver 50 people at State level
35 districts staffs35 districts staffs
Millions in research dollars Millions in research dollars
An inventory for an air quality plan An inventory for an air quality plan may take 1-3 years and $500k to may take 1-3 years and $500k to $1million $1million
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26California Air Resources Board
Lessons LearnedLessons Learned
Need for regulatory frameworkNeed for regulatory framework Inventories take time and resources Inventories take time and resources Inventory development is a Inventory development is a
continuous and iterative processcontinuous and iterative process Reduced emission means improved Reduced emission means improved
air qualityair quality
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Planning for the Planning for the Development of Development of
Emission InventoriesEmission Inventories
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28California Air Resources Board
Developing Emission Developing Emission InventoriesInventories
Planning for inventory Planning for inventory developmentdevelopment
Data collectionData collection
Data management and reportingData management and reporting
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Type and ScopeType and Scope
Emission Inventories forEmission Inventories forAir Quality PlanningAir Quality Planning
Emission Inventories forEmission Inventories forAir Quality PlanningAir Quality Planning
InventoryInventoryObjectivesObjectives
resolutionresolution
sourcessourcespollutantspollutants
regionregion
AvailableAvailableResourcesResources MethodologiesMethodologiesMethodologiesMethodologies
Responsible PartiesResponsible Parties
ExistingExistingInformationInformation
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30California Air Resources Board
Selection of MethodsSelection of Methods
Intended use of inventory Intended use of inventory
Availability of dataAvailability of data
Practicality of methodPracticality of method
Priority of categoryPriority of category
Time/ResourcesTime/Resources
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31California Air Resources Board
MethodologiesMethodologies Top down approachTop down approach Continuous emission monitorsContinuous emission monitors Source testingSource testing Material balanceMaterial balance Emission factorsEmission factors Fuel analysisFuel analysis SurveysSurveys Engineering judgementEngineering judgement
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32California Air Resources Board
Estimation ModelsEstimation Models BEIS BEIS (biogenics)(biogenics)
Landfill Gas Emission ModelLandfill Gas Emission Model TANKS TANKS (storage tanks)(storage tanks)
MECH MECH (PM emissions form road, ag.)(PM emissions form road, ag.)
PM Calc PM Calc (PM(PM2.52.5 emissions) emissions)
MOBILE6 / EMFAC2000MOBILE6 / EMFAC2000 OFFROADOFFROAD Model Model
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33California Air Resources Board
Where to Find InformationWhere to Find Information Emission Inventory Improvement Emission Inventory Improvement
Program Program (EIIP)(EIIP)– 10 volumes of methods10 volumes of methods
California Air Resources BoardCalifornia Air Resources Board– Area Source ManualArea Source Manual– Speciation ManualsSpeciation Manuals– CATEF toxic emission factorsCATEF toxic emission factors
U. S. EPAU. S. EPA – CHIEF clearinghouse CHIEF clearinghouse – Fire Database (toxic factors)Fire Database (toxic factors)
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Data Collection & ManagementData Collection & ManagementData Collection & ManagementData Collection & Management
ReportsReportsAnnual AverageAnnual Average
SeasonalSeasonalForecastedForecasted
GriddedGridded
Collect Collect DataData
Calculate Calculate EmissionsEmissions
Quality Quality AssuranceAssurance
DocumentationDocumentation
Data Handling Data Handling SystemSystem
ReportsReports
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Calculate EmissionsCalculate Emissions
Process RateProcess Rate (ActivityActivity)
Number ofNumber of UnitsUnits
EmissionEmissionFactorFactorxx
EmissionsEmissions per Unitper Unit
xx
EmissionsEmissions==
TotalEmissions
==
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36California Air Resources Board
Data CollectionData Collection
Activity dataActivity data
Emission factorsEmission factors
Facility information Facility information
Spatial and temporalSpatial and temporal
SpeciationSpeciation
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37California Air Resources Board
Data Quality ObjectivesData Quality Objectives
AccuracyAccuracy // uncertaintyuncertainty CompletenessCompleteness RepresentativenessRepresentativeness ComparabilityComparability Consistency Consistency ReasonablenessReasonableness
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38California Air Resources Board
DocumentationDocumentation
Methods usedMethods used
Sources of dataSources of data
AssumptionsAssumptions
CalculationsCalculations
CommunicationCommunication
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39California Air Resources Board
Data ManagementData Management
NeedsNeeds // capabilitiescapabilities
ExpandabilityExpandability // flexibilityflexibility
Computer systemComputer system
Ease of useEase of use
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40California Air Resources Board
Data ReportingData Reporting
Annual average Annual average
Seasonal Seasonal
Forecasted Forecasted
GriddedGridded // modeling modeling
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41California Air Resources Board
Forecasting EmissionsForecasting Emissions
Forecast emissions based on Forecast emissions based on expectations of future economic expectations of future economic conditions, population growth, and conditions, population growth, and emission controlsemission controls
Need a baseline emission Need a baseline emission inventory, growth factors and inventory, growth factors and control factorscontrol factors
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Gridded/Modeling Gridded/Modeling EmissionsEmissions
Determined by model selectionDetermined by model selection
Spatially and temporallySpatially and temporallyresolvedresolved
Hourly emissions byHourly emissions bygrid cellgrid cell
Day specific emissions Day specific emissions
Gridded NOx Emissions
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Los Angeles CountyLos Angeles CountyGridded ROGGridded ROG
Facilities emitting greater than 100 tons/year ROG shown.
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44California Air Resources Board
Resources NeededResources Needed
Dependent on Dependent on OBJECTIVESOBJECTIVES!!
Minimum of 18 months - 3 years?Minimum of 18 months - 3 years?
4-6 people full time?4-6 people full time?
$500k to $1 million?$500k to $1 million?
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Clean Air
Air Quality MonitoringAir Quality Monitoring
Emission InventoryEmission Inventory
Air Quality Air Quality ModelingModeling
ControlControlStrategyStrategy
Building an Air Quality PlanBuilding an Air Quality Plan
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ConclusionsConclusionsConclusionsConclusions Plan for inventory developmentPlan for inventory development Identify needsIdentify needs Identify resourcesIdentify resources Build on what others Build on what others
have donehave done Schedule to allow timeSchedule to allow time Cooperative efforts Cooperative efforts
needed between needed between agencies & businessesagencies & businesses
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47California Air Resources Board
ARB Emissions Contact:ARB Emissions Contact:Linda Murchison, Ph.D.Linda Murchison, [email protected]@arb.ca.gov916-322-6021916-322-6021
Web Site:Web Site:http://arb.ca.gov/http://arb.ca.gov/emisinv/eib.htmemisinv/eib.htm
California Air ResourcesCalifornia Air ResourcesBoardBoard
Contact and InformationContact and Information
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ENDEND
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California Air Resources Board
Emission InventoryEmission Inventory
Discussion GroupDiscussion Group
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Type and ScopeType and Scope
Emission Inventory PlanningEmission Inventory PlanningEmission Inventory PlanningEmission Inventory Planning
ObjectivesObjectives
resolutionresolution
sourcessourcespollutantspollutants
regionregion
AvailableAvailableResourcesResources MethodologiesMethodologiesMethodologiesMethodologies
Responsible PartiesResponsible Parties
ExistingExistingInformationInformation
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Inventories Inventories for Air for Air QualityQualityModelsModels
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52California Air Resources Board
Air Quality ModelsAir Quality Models
Use emissions, atmospheric Use emissions, atmospheric chemistry, and meteorological chemistry, and meteorological data to predict pollutant data to predict pollutant concentrations concentrations in the atmospherein the atmosphere
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Modeling Input DataModeling Input Data
Speciated, gridded emission dataSpeciated, gridded emission data
Surface and aloft meteorological Surface and aloft meteorological measurementsmeasurements
Atmospheric chemistry Atmospheric chemistry
Extensive air quality Extensive air quality monitoring datamonitoring data
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54California Air Resources Board
Modeling Output DataModeling Output Data
Prediction of air quality impacts Prediction of air quality impacts based on changes in emissions based on changes in emissions or meteorologyor meteorology
Evaluate mix of emissions Evaluate mix of emissions reductions to best improve air reductions to best improve air qualityquality
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55California Air Resources Board
EmissionsEmissions ActualActual
– Measured or estimated emissions which most accurately represent the emissions from an emissions Measured or estimated emissions which most accurately represent the emissions from an emissions unit. For example: The actual rate of emissions is defined in tons per year of any regulated pollutant unit. For example: The actual rate of emissions is defined in tons per year of any regulated pollutant emitted from a major source over the preceding two years. Actual emissions shall be calculated using emitted from a major source over the preceding two years. Actual emissions shall be calculated using the unit's actual operating hours, production rates,and types of materials processed, stored, or the unit's actual operating hours, production rates,and types of materials processed, stored, or combusted during the preceding calendar year or other defined period. For a new emission unit, actual combusted during the preceding calendar year or other defined period. For a new emission unit, actual emissions equal the potential to emit of the unit.emissions equal the potential to emit of the unit.
AllowableAllowable– Permitted emissions levels. Actual should not exceed allowable emissions.Permitted emissions levels. Actual should not exceed allowable emissions.
PotentialPotential– The maximum physical and operational design capacity to emit a pollutant. Limitations on the physical The maximum physical and operational design capacity to emit a pollutant. Limitations on the physical
or operational design capacity, including emissions control devices and limitations on hours of or operational design capacity, including emissions control devices and limitations on hours of operation, may be considered only if such limitations are incorporated into the applicable Authority to operation, may be considered only if such limitations are incorporated into the applicable Authority to Construct and Permit to Operate. EPA Part 70 regulations define potential to emit as the "maximum Construct and Permit to Operate. EPA Part 70 regulations define potential to emit as the "maximum capacity of a stationary source to emit any air pollutant under its physical and operational design." In capacity of a stationary source to emit any air pollutant under its physical and operational design." In general, this definition means that emissions from a source must be estimated at maximum capacity general, this definition means that emissions from a source must be estimated at maximum capacity over 365 days per year. over 365 days per year.
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56California Air Resources Board
Success in Clean AirSuccess in Clean Air Due to stringent control programDue to stringent control program
Must account for growthMust account for growth
Stationary ControlsStationary Controls– control of industrial sourcescontrol of industrial sources– consumer products, paintsconsumer products, paints
Mobile ControlsMobile Controls– engine standardsengine standards– retrofit existing enginesretrofit existing engines– clean fuelsclean fuels
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57California Air Resources Board
Databases for Developing Databases for Developing InventoriesInventories
Microsoft Access DatabaseMicrosoft Access Database
Oracle DatabaseOracle Database
Paradox DatabaseParadox Database
Dbase DatabaseDbase Database
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58California Air Resources Board
SCCs Define and Categorize SCCs Define and Categorize Emissions Related DataEmissions Related Data
Identify Emission ProcessesIdentify Emission Processes 8 Digit Source Classification Codes8 Digit Source Classification Codes Created by U.S. EPACreated by U.S. EPA Over 7100 Valid SCCs Now AvailableOver 7100 Valid SCCs Now Available Important to Assign SCCs CorrectlyImportant to Assign SCCs Correctly
Source Classification Codes Source Classification Codes (SCC) System(SCC) System
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59California Air Resources Board
Gridded and Modeling Gridded and Modeling Emission Inventories Emission Inventories (cont.)(cont.)
How are emissions spatially How are emissions spatially allocated?allocated?
– Point sources - UTM coordinatesPoint sources - UTM coordinates
– Area sources - spatial surrogates (land Area sources - spatial surrogates (land use or population)use or population)
– Mobile sources - motor vehicle emission Mobile sources - motor vehicle emission and transportation modelsand transportation models
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60California Air Resources Board
Growth FactorsGrowth Factors
What are growth factors?What are growth factors?– Factors based on specific economic Factors based on specific economic
profiles for certain industry typesprofiles for certain industry types– or based on demographic dataor based on demographic data
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61California Air Resources Board
Control FactorsControl Factors
What are control factors?What are control factors?– Control factors are derived from rules and Control factors are derived from rules and
regulations which impose emission regulations which impose emission reductions or a technological change on a reductions or a technological change on a particular emission process. particular emission process.
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62California Air Resources Board
Emission ControlsEmission Controls
Motor VehicleMotor Vehicle– catalyst, vapor recovery, OBD, clean fuelscatalyst, vapor recovery, OBD, clean fuels
Stationary SourcesStationary Sources
– scrubbers, cyclones, electrostatic scrubbers, cyclones, electrostatic precipitators, bag housesprecipitators, bag houses
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63California Air Resources Board
CARB Mobile Source and Fuels CARB Mobile Source and Fuels Regulations and ProgramsRegulations and Programs
New engine emission standards New engine emission standards In-use durability requirementsIn-use durability requirements Retrofit existing enginesRetrofit existing engines Cleaner fuels: gasoline, diesel, natural Cleaner fuels: gasoline, diesel, natural
gasgas Promote national and international Promote national and international
standards for trucks, ships, and aircraftstandards for trucks, ships, and aircraft New technologies for the futureNew technologies for the future
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64California Air Resources Board
CARB Cleaner Fuels CARB Cleaner Fuels ProgramProgram
1992: Eliminated lead from gasoline, 1992: Eliminated lead from gasoline, limited vapor pressure, required limited vapor pressure, required oxygenates in winter to reduce carbon oxygenates in winter to reduce carbon monoxidemonoxide
1996: Introduced “cleaner-burning 1996: Introduced “cleaner-burning gasoline” to achieve maximum gasoline” to achieve maximum reductions in ozone and toxicsreductions in ozone and toxics
1999: Phase out MTBE by 2002, 1999: Phase out MTBE by 2002, reduce sulfur and benzene furtherreduce sulfur and benzene further
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65California Air Resources Board
CARB NOx Emission Standards for On-Road Trucks
0
2
4
6
8
10
12 g/hp-hr
1990
1991
1998
2004
1985
Possible Future Standards• NOx aftertreatment-based• 75-90% reduction • 2007 goal
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66California Air Resources Board
CARB PM Emission StandardsFor On-Road Trucks
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7 g/hp-hr
1988
1991
1994truck
bus
Possible Future Standards• PM trap-based• ~90% Reduction • 2007 goal
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67California Air Resources Board
Diesel PM and NOx Diesel PM and NOx ControlsControls
Cleaner diesel fuelCleaner diesel fuel– Very low sulfur enables after-treatment Very low sulfur enables after-treatment
Exhaust after-treatmentExhaust after-treatment– PM traps > 90% efficientPM traps > 90% efficient– NOx catalysts 50-90% efficiency potentialNOx catalysts 50-90% efficiency potential
Alternative fuels: natural gasAlternative fuels: natural gas
New technologies: fuel cellsNew technologies: fuel cells
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68California Air Resources Board
Cleaner Industrial SourcesCleaner Industrial Sources
Best controls on new and existing sourcesBest controls on new and existing sources
Controls for NOx, ROG, SOx, CO, toxicsControls for NOx, ROG, SOx, CO, toxics
Diesel particulate matter controls to Diesel particulate matter controls to reduce toxics risk reduce toxics risk
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69California Air Resources Board
Cleaner Consumer ProductsCleaner Consumer Products CARB CARB has set ROG emission limits for has set ROG emission limits for
nearly 50 categories of consumer products nearly 50 categories of consumer products and 35 categories of aerosol paints and and 35 categories of aerosol paints and coating products.coating products.
• CARB regulations will reduce CARB regulations will reduce emissions by 53 tons per day in Los emissions by 53 tons per day in Los AngelesAngeles
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Relative Toxics Risk for Relative Toxics Risk for Diesel PMDiesel PM
Based on CARB’s 1995 -1997 ambient monitoring data and estimated diesel PM concentrations
Ben
zene
Ben
zene
1,3-
But
adie
ne
1,3-
But
adie
ne
Chr
ome
VI
Chr
ome
VIC
arbo
n Te
trac
hlor
ide
Car
bon
Tetr
achl
orid
e
Form
alde
hyde
Form
alde
hyde
para
-Dic
hlor
oben
zene
para
-Dic
hlor
oben
zene
Perc
hlor
oeth
ylen
e
Perc
hlor
oeth
ylen
e
Ace
tald
ehyd
e
Ace
tald
ehyd
e
All
Oth
ers
All
Oth
ers
Die
sel P
M
Die
sel P
M
Co
ntr
ibu
tio
n t
o S
tate
wid
e C
ance
r R
isk
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On-Road Diesel9%
On-Road Gas2%
Tire & Brake2%
Off-Road Moble10%
Industrial14%
Burning30%
Geologic33%
Organic Carbon18%
Elemental Carbon
8%
Sodium1%
Chloride1%
Geologic6%
Sulfate9%
Nitrate40%
Ammonium17%
Emissions Inventory Ambient Species(CMB analysis - all species)
Slices with lines are secondary PM
Does not include secondary PMRubidoux, 1997 AQMP, App. V, SCAQMD
Direct & Secondary PMDirect & Secondary PM2.52.5
Inventory vs Ambient Air Inventory vs Ambient Air for SCAQMDfor SCAQMD
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72California Air Resources Board
What is in the Air?What is in the Air?Mobile6%
Industrial5%
Geologic6%
Burning16%
Nitrates67%
Secondary compoundsSecondary compoundssometimes significantsometimes significant
Extremely variableExtremely variable– By seasonBy season– By locationBy location– By dayBy day
San Joaquin Valley PMSan Joaquin Valley PM2.52.5
(hypothetical winter day)(hypothetical winter day)
From ammonia and From ammonia and
combustion exhaustcombustion exhaust
primary, directprimary, direct
emissionsemissions
secondarysecondary
emissionsemissions
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73California Air Resources Board
PMPM1010 Inventoried Sources Inventoried SourcesSouth Coast Air Basin, 1996South Coast Air Basin, 1996
On-Road Mobile6%
Other Mobile4%
Industrial & Other7%
Waste Burning1%
Residential Wood Burn6%
Wildfires4%
Conctruction11%
Farming4%
Paved Road Dust41%
Fugitive Windblown
4%
Unpaved Road Dust12% Source: ARB 1996 Statewide Inventory
440 tons/day
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74California Air Resources Board
NONOxx Inventoried Sources Inventoried SourcesSouth Coast Air Basin, 1996South Coast Air Basin, 1996
On-Road Gasoline45%
On-Road Diesel18%
Other Mobile22%
Fuel Combustion10%
Industrial2%
Areawide3%
1100 tons/daySource: ARB 1996 Statewide Inventory
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75California Air Resources Board
ROG Inventoried SourcesROG Inventoried SourcesSouth Coast Air Basin, 1996South Coast Air Basin, 1996
On-Road Gasoline42%
On-Road Diesel3%
Other Mobile9%
Fuel Combustion1%
Degreasing9%
Coatings13%
Other Stationary9%
Consumer Products
9%
Misc5%
1100 tons/daySource: ARB 1996 Statewide Inventory
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Emission trends NOEmission trends NOxx
19851990
1995
0
400
800
1200
1600
Em
issi
on
s (t
on
s p
er d
ay)
Stationary Area-wide Gasoline VehiclesDiesel Vehicles Other Mobile Source: 1999 California Almanac
of Emissions & Air Quality, ARB
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Emission trends ROGEmission trends ROG
19851990
1995
0
400
800
1200
1600
2000
Em
issi
on
s (t
on
s p
er d
ay)
Stationary Area-wide Gasoline VehiclesDiesel Vehicles Other Mobile Source: 1999 California Almanac
of Emissions & Air Quality, ARB
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Emission trends PMEmission trends PM1010
19851990
1995
0
400
800
Em
issi
on
s (t
on
s p
er d
ay)
Stationary Area-wide Gasoline VehiclesDiesel Vehicles Other Mobile Source: 1999 California Almanac
of Emissions & Air Quality, ARB
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Passenger Car Exhaust Passenger Car Exhaust Changes for Southern CaliforniaChanges for Southern California
Year 2000, by Emissions ModelYear 2000, by Emissions Model
0
50
100
150
200
250
300
TOG CO NOx PM10
7E
7F
7G
2K
ton
s/d
ay
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Statewide, 2000 Statewide, 2000 NONOxx, ROG, ROG
Stationary19%
Area-wide3%
On-road47%
Other Mobile
31%
NONOxx
Stationary23%
Area-wide28%
On-road35%
Other Mobile
14%
ROGROG
Stationary17%
Area-wide3%
On-road52%
Other Mobile
28%
NONOxx
Stationary20%
Area-wide24%
On-road44%
Other Mobile
12%
ROGROG
OldOldEstimateEstimate
RevisedRevisedEstimateEstimate