AN IMPLEMENTATION PLAN
FOR
SUSPENDED PARTICULATE MATTER
IN THE LOS ANGELES REGION
FINAL REPORT
Prepared for
ENVIRONMENTAL PROTECTION AGENCY
REGION X - SAN FRANCISCO, CALIFORNIA
K.WW/0
OTRANSPOHiATION AND
£NVIRONM£HTAL ENGINEERING
PEftATiONS
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AN IMPLEMENTATION PLAN FOR SUSPENDED
PARTICULATE MATTER IN THE LOS ANGELES REGION
FINAL REPORT
By: John Trijonis (Project Manager)
George Richard (Assistant Project Manager)
Kimm Crawford
Ronald Tan
Ronald Wada
Prepared For
Environmental Protection Agency
Region IX - San Francisco, California
MARCH 1975
TRW/
O TRANSPORTAT ION AND
ENVIRONMENTAL ENGINEERING
PERATIONS
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DISCLAIMED
This report was furnished to the Environmental Protection Agency by
TRW Transportation and Environmental Operations in fulfillment of Contract
Number 68-02-1384. The contents of this report are reproduced herein as
received from the contractor. The opinions, findings, and conclusions
are those of TRW and not necessarily those of the Environmental Protec-
tion Agency. Mention of company or product names does not constitute
endorsement by the Environmental Protection Agency.
n
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TABLE OF CONTENTS
1.0 INTRODUCTION 1-1
1.1 Basic Definitions 1-3
1.2 Limitations in the Scope of the Study 1-5
1.3 Summary of Conclusions and Recommendations 1-10
2.0 BASIC TECHNICAL BACKGROUND INFORMATION 2-1
2.1 Analysis of Air Monitoring Data 2-2
2.1.1 Review of the Hi-Vol Sampling Method 2-2
2.1.2 Review of Monitoring Programs in the
Los Angeles Region 2-8
2.1.3 Characterization of Hi-Vol Levels in the
Los Angeles Region for the 1972 Base Year ... 2-13
2.2 Emission Inventories and Projections 2-25
2.2.1 Development of the 1972 Base Year Inventory . 2-25
2.2.2 Development of Emission Projections for 1977
and 1980 2-41
2.3 A Methodology for Relating Emission Levels to Ambient
Particulate Air Quality 2-59
2.3.1 Characterization of Aerosol Origins in the
Metropolitan Los Angeles Region 2-60
2.3.2 The Dependence of Suspended Particulate Levels
on Contaminant Emissions 2-71
2.3.3 Illustration of the Complete Model 2-87
3.0 ALTERNATIVE EMISSION CONTROL MEASURES 3-1
3.1 General Control Methods Available 3-2
3.1.1 Controls for Primary Particulates 3-2
3.1.2 Controls for Gaseous Precursors 3-9
3.1.3 Alternative Fuels - A Control for Particulates,
S02 and NO 3-25
3.1.4 Non-TechnoTogical Control Measures 3-29
3.2 Summary of Control Alternatives for Emission Sources
i n the Four County Area 3-33
3.2.1 Petroleum Industry 3-42
3.2.2 Stationary Fuel Combustion 3-47
3.2.3 Minerals Industry 3-58
3.2.4 Aircraft Operations 3-62
3.2.5 Motor Vehicles 3-76
3.2.6 Organi c Sol vents 3-91
3.2.7 Metallurgical Processes 3-94
iii
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TABLE OF CONTENTS (Cont)
4.0 EVALUATION OF ALTERNATIVE CONTROL STRATEGY SCENARIOS 4-1
4.1 Control Strategy I: A Reasonable/Implementable
Scenario for 1977 and 1980 4-1
4.1.1 Impact on Emission Levels 4-2
4.1.2 Air Quality Impact 4-6
4.1.3 Control Costs 4-9.
4.1.4 Implementation Problems 4-13
4.2 Control Strategy II: Maximal Technological Control
for 1977 4-16
4.2.1 Impact on Emission Levels 4-19
4.2.2 Ai r Qual i ty Impact 4-20
4.2.3 Control Costs 4-23
4.2.4 Implementation Problems 4-26
4.3 Control Strategy III: A Delayed Scenario for 1980
Based on Methanol Conversion 4-28
4.3.1 Impact on Emissions Levels. 4-31
4.3.2 Air Quality Impact 4-32
4.3.3 Control Costs 4-35
4.3.4 Implementation Problems 4-38
4.4 Control Strategy IV: A Drastic Source-Relocation/VMT-
Reduction Strategy to Attain the Primary Air Quality
Standard by 1980' 4-40
4.4.1 Impact on Emission Levels 4-43
4.4.2 Air Quality Impact 4-44
4.4.3 Control Costs 4-47
4.4.4 Implementation Problems 4-48
5.0 CONCLUSIONS AND RECOMMENDATIONS 5-1
5.1 Control Strategy Recommendations 5-1
5.2 Conclusions and Recommendations Resulting from the
Technical Support Analyses 5-8
IV
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LIST OF TABLES
Table Page
2-1 Sampling Sites and Sampling Frequency of the APCD, NASN,
and Chess Monitoring Programs in the Los Angeles Region ... 2-8
2-2 APCD, NASN, and Chess Annual Hi-Vol Levels, AGM'S for
1967-1973 i 2-12
2-3 Equivalency Tests for APCD and NASN Hi-Vol Geometric
Means 2-13
2-4 The National Ambient Air Quality Standards for Particulates 2-14
2-5 Monitoring Sites for the 1972 Base Year Air Quality
Characterization 2-17
2-6 Expected Measured 24 Hour Maxima vs. Expected Actual 24
Hour Maxima for Hi-Vol Monitoring Sites in the Los Angeles
Region 2-21
2-7 Characteristic Maximal Hi-Vol Levels in Three Subareas of
the Los Angeles Region -- (For Base Year 1972) 2-24
2-8 1972 Emission Inventory of Primary Particulates and
Gaseous Precursors for the Four County Area 2-31
2-9 Summary of Assumptions and Data Sources used for Baseline
Emission Inventory Projections to 1977 and 1980 2-43
2-10 Projected Emission Inventory for the Four County Area
when the Present Emissions Control Program is Implemented . 2-48
2-11 Projected Emission Inventory for the Four County Area
when the EPA Air Program is Implemented 2-49
2-12 Estimates of Average Total Background Levels 2-63
2-13 Background Aerosol Classification Scheme for the Los
Angeles Region 2-64
2-14 Hi-Vol Particulate Composition: Characterization for the
1972 Base Year 2-66
2-15 First Iteration Calculation Methods for Non-Background
Origin Categories 2-67
2-16 Aerosol Origin Characterization., First Iteration
(Annual Arithmetic Mean -- ug/m ) 2-68
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LIST OF TABLES (Cont)
Tables Pages
2-17 Origin Characterization for Annaul Mean Hi-Vol Parti-
cipate Levels (ug/m3) 2-70
2-18 Hypothetical Illustration of the Model for Predicting
Control Strategy Impact on Particulate Air Quality
Level s 2-88
2-19 Breakdown of Primary Particulate and Sulfate Contribu-
tions at Chino 2-90
3-1 Installed Costs of Control Equipment 3-4
3-2 Scrubber Capabilities 3-7
3-3 Process for Desulfurization of Effluent Gas Streams Proces-
sed Principally in the Gas Phase 3-16
3-4 SOp Removal Processes Currently in Test 3-22
3-5 Alternative Control Measures, for Prevention of Particu-
late Emissions in the Four-County Area 3-34
3-6 Alternative Control Measures for Prevention of S02 Emissions
in Four-County Area 3-35
3-7 Alternative Control Measures for Prevention of NO Emissions
in Four-County Area 3-36
3-8 Inventory of Hydrocarbon Emissions Under the EPA Oxidant
Implementation Plan, Four County Area 3-37
3-9 Emissions of Particulates, S0?, and NO from Refinery Opera-
tions, Four-County Area, 1972 ... 3-42
3-10 Characterization of Control Methods Currently Utilized in
Petroleum Industry For Control of Major Particulate Emission
Sources, Four-County Area, 1972 3-43
3-11 Summary of Fuel Burning Equipment 3-47
3-12 Pollutant Emissions by Fuel Type Consumed for Basic Com-
bustion Categories in Four-County Area 3-48
3-13 Cost of Particulate Emission Control for Oil-Burinig
Combustion Equipment, 1977 3-51
3-14 The Effect of NO Emission Controls on Fuel Combustion
Equipment, Four-County Area 3-53
vi
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LIST OF TABLES (Cont)
Tables Pages
3-15 Impact of Conversion to Methyl-Fuel in Combustion Units
in Four-County Area 3-58
3-16 Summary of Emission Controls Currently Utilized in
Minerals Industry of Four-County Area 3-60
3-17 Aircraft Emissions, Present and Projected, Piston and Jet . 3-63
3-18 Engine Modifications for Emission Control for Existing and
Future Turbine Engines 3-66
3-19 Effectiveness of Engine Modification in Control of Emissions
from Turbine Engines, by Operating Mode 3-67
3-20 Modal Emissions Distribution for Principal Jet Engines in
Use 3-68
3-21 Impact of Alternative Control on Overall Jet Aircraft
Emissions 3-69
3-22 Time and Costs for Modification of Current Civil Aviation
Engines 3-70
3-23 Cost Effectiveness for Turbine Retrofit Measures, 1977,
Four County Area 3-70
3-24 Comparative Reductions Resulting from Control Methods
Applied at Los Angeles International Airport 3-73
3-25 Engine Modifications for Emission Control for Existing and
Future Piston Engines 3-75
3-26 Role of Motor Vehicle Emissions in Atmospheric Pollution of
Four County Area 3-76
3-28 The Effect of Lead Removal in Motor Fuels on Motor Vehicle
Particulate Exhaust Emissions in Four County Area 3-83
3-29 The Effect of Automotive Fuel Desulfurization (100 ppm)
On Motor Vehicle Emissions in Four County Area 3-85
3-30 Cost of Desulfurization of Vehicle Fuels for Control of
Exhaust Emissions 3-86
3-31 Impact of Particulate Traps on Particulate Emissions from
Motor Vehicles in Four County Area 3-88
3-32 Impact of Scrubber on S0? and Particulate Emissions from
Motor Vehicles in Four County Area 3-90
vii
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LIST OF TABLES (Cont)
Tables Pages
3-33 Emissions from Paint Spray Booths and "Other" Organic
Solvent Operations, Four County Area, 1972 3-93
3-34 Characterization of Furnace Control Effectiveness, Four
County Area, 1972 3-96
4-1 Control Strategy I - Reasonable/Implementation Strategy
for 1977 and 1980 4-3
4-2 Emission Projections from Control Strategy I for the 4
County Sub-Area 4-4
4-3 Primary Particulate and S02 Emission Estimates for the
Kaiser/Edison Complex in tne Western San Bernardino County
Hot-Spot Under Control Strategy I 4-5
4-4 Cost of Control Measures for Control Strategy I (Reasonable/
Implementable Scenario for 1977 & 1980) 4-10
4-5 Control Strategy II - Maximal Technological Control for
1977 4-18
4-6 Emission Projections from Control Strategy II for the 4
County Sub-Area 4-19
4-7 Primary Particulate and SOp Emission Estimates for the
Kaiser/Edison Complex in tne Western San Bernardino County
Hot-Spot Under Control Strategy II 4-20
4-8 Cost of Control Measures for Control Strategy II (Maximal
Technological Scenario for 1977) 4-24
4-9 Control Strategy III - A Delayed Scenario for 1980 Based on
Methanol Conversion 4-30
4-10 Emission Projections from Control Strategy III for the 4
County Sub-Area 4-31
4-11 Primary Particulate and S02 Emission Estimates for the
Kaiser/Edison Complex in tne Western San Bernardino County
Hot-Spot Under Control Strategy III 4-32
4-12 Cost of Control Measures for Control Strategy III (Delayed
Methanol Conversion Scenario for 1980) 4-36
4-13 Control Strategy IV - A Drastic Source Relocation/ VMT
Reduction Strategy to Attain the Primary Air Quality
Standard by 1980 4-41
viii
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LIST OF TABLES (Cont)
Tables Pages
4-14 Emission Projections from Control Strategy IV for the
4 County Sub-Area 4-43
4-15 Primary Particulate and SCL Emission Estimates for the
Kaiser/Edison Complex in tne Western San Bernardino County
Hot-Spot under Control Strategy IV 4-44
5-1 Summary of Air Quality Impacts, Control Costs, and Imple-
mentation Problems Associated with the Alternative Control
Strategies 5-3
5-2 Sulfate Air Quality Impact of the Recommended Strategies .. 5-7
IX
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LIST OF FIGURES
Page
T-l Metropolitan Los Angeles Air Quality Control Region 1-6
2-1 Hi-Volume Sampler and Shelter 2-3
2-2 APCD, NASN, and CHESS Hi-Vol Sites in the Metropolitan
Los Angeles Region 2-9
2-3 Expected Annual Geometric Mean Hi-Vol Levels for the 1972
Base Year 2-18
2-4 Expected 24-Hour Max. Hi-Vol Levels for the 1972 Base Year
(for the Present APCD Monitoring Frequency) 2-20
2-5 Sub-Areas for Control Strategy Formulation 2-23
2-6 The Role of the Various Source Categories in Emission of
Particulates and Gaseous Precursors in the Four County Area, 1972 2-32
2-7 Particulate Emission Density Map 2-37
2-8 Sulfur Oxides Emissions Density Map 2-38
2-9 Reactive Hydrocarbon Emission Density Map 2-39
2-10 Nitrogen Oxides Emission Density Map 2-40
2-11 Projection of Particulate Emissions in Four County Area .... 2-50
2-12 Projection of NO Emissions in Four County Area 2-50
A
2-13 Projection of SO^ Emissions in Four County Area 2-50
2-14 Projection of Reactive Hydrocarbon Emissions in Four County Area 2-50
2-15 The Projected Role of the Various Major Source Categories in
Emissions of Particulates and Gaseous Precursors in the Four
County Area under the EPA Air Program 2-52
2-16 Locations for the Aerosol Origin Characterization 2-62
2-17 Estimated Non-Background Primary Particulate Levels in the
Los Angeles Region 2-72
2-18 Total Sulfate Levels in the Los Angeles Region 2-73
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LIST OF FIGURES (Continued)
Page
2-19 Total Nitrate Levels in the Los Angeles Region 2-74
2-20 Estimated Non-Background Secondary Organic Levels in the
Los Angeles 2-75
2-21 Schematic Illustration of the Dependence of Sulfate Levels
on S02 Input 2-79
2-23 Sulfur Dioxide/Sulfate Relationship for 18 U.S. Cities 2-81
2-24 Aerometric Relationship Between Sulfate and Sulfur Dioxide in
the Metropolitan Los Angeles AQCR 2-82
2-25 Aerometric Relationship Between Nitrate and NO in the
Metropolitan Los Angeles AQCR 2-85
2-26 Suspended Particulate Air Quality Forecasts for the Baseline
Emission Projections, (Present Controls and EPA Oxidant Plan). . 2-92
3-1 Continued Improvement in VHO Isomax Process 3-10
3-2 Cost to Desulfurize Arabian Heavy Crude Oil with VGO Isomax . . 3-11
3-4 Role of Aircraft Emissions in Atmospheric Pollution of
Four County Area 3-63
3-5 Gaseous Emission Characteristics of a JT8D Turbine Engine . . . 3-72
3-6 Emission Characteristics for Piston Engine 3-74
3-7 The Effect of Exhaust Emission Standards on Pollutant Emissions
from Various Vehicle Categories 3-80
4-1 Air Quality Impact of Control Strategy I on Suspended
Particulate Levels in the Los Angeles Region 4-7
4-2 Air Quality Impact of Control Strategy II on Suspended
Particulate Levels in the Los Angeles Region 4-21
4-3 Air Quality Impact of Control Strategy III on Suspended
Particulate Levels in the Los Angeles Region 4-33
4-4 Air Quality Impact of Control Strategy IV on Suspended
Particulate Levels in the Los Angeles Region 4-45
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BLANK PAGE
xii
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1.0 INTRODUCTION
This report presents the results of a study, prepared under contract
to the Environmental Protection Agency, to develop a particulate implemen-
tation plan for the Metropolitan Los Angeles Air Quality Control Region.
The Los Angeles Region presently experiences suspended particulate levels
well in excess of the National Ambient Air Quality Standards (NAAQS). This
study formulates control strategies which produce substantial reductions in
suspended particulate levels and evaluates the impact of these strategies
in 1977 and 1980.
A principal goal of the present project is to identify a control stra-
tegy that will actually attain the NAAQS for particulates in the Los Angeles
Region. Such a plan has been formulated and is described in the final chap-
ters of this report. However, because of the severity of tha Los Angeles
particulate problem and because of significant background (non-controllable)
particulate levels, the strategy for standard attainment is of a very drastic
nature. Great socio-economic disruption and extreme implementation pro-
blems are inherent in the standard attainment strategy. Thus, this study
formulates and recommends other (less drastic) control plans for actual
implementation. These strategies do not attain the suspended particulate
air quality standards, but they do achieve substantial improvement in par-
ticulate air quality. These alternative plans result in much more acceptable
socio-economic costs and much more manageable implementation problems than
the standard attainment strategy.
1-1
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The present chapter serves as an overall introduction and sumnary for
the study. The remainder of this section describes the organization of this
report. Section 1.1 discusses basic definitions and establishes a consistent
terminology. Section 1.2 deals with the limitations in scope which have
been established for the project. In Section 1.3, the principal conclu-
sions and recommendations of the study are reviewed.
Chapter 2 deals with basic technical background information. Before
control strategies can be systematically formulated and evaluated, certain
basic technical analyses must be performed. Chapter 2 summarizes the ana-
lytical foundation which has been established for this study. Three areas
are covered: (1) analysis of particulate air monitoring procedures and
characterization of present air quality levels in Los Angeles, (2) compilation
of emission inventories and projections for both primary particulates and
gaseous precursors of secondary particulates, and (3) development of a
methodology to translate changes in emission levels into changes in air
quality levels. More detailed descriptions of the technical analyses asso-
ciated with each of these areas are found in Support Documents #1, #2, and
#3 to this report, [ 1 ], [2], [3].
Chapter 3 presents alternative emission control measures for primary
particulates and for gaseous precursors of secondary particulates. The
emission reduction effectiveness, economic costs, and implementation pro-
blems associated with each measure are described. The control measures are
organized according to both source type and pollutant type. Detailed data
are presented for technological controls, but only qualitative discussions
are given on non-technological (administrative) controls. Chapter 3 essen-
tially consists of a summary of Support Document #4 which gives a more
comprehensive analysis of the alternative control measures for various sources, [4]
1-2
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Chapter 4 describes and evaluates four alternative control strategy
scenarios, each composed of various combinations of the control measures
given in Chapter 3. The first strategy, called the "reasonable/implementable
scenario", centers on a general policy of fuel desulfurization, along with
some add-on controls for particulate and NOV emissions. The second strategy
A
consists of maximal technological controls for all sources. Strategy III
is a delayed scenario, involving methanol conversion for stationary fuel
conbustion sources and some add-on control measures. The final strategy
combines the maximal technological controls with a drastic source reloca-
tion/VMT reduction scheme so as to provide for attainment of the particulate
air quality standards. Each control scenario calls for the EPA oxidant
implementation plan as a concurrent control for suspended particulates.
For every strategy, an evaluation is made of emission reductions, air
quality impact, economic costs, and implementation problems.
The final chapter presents conclusions and recommendations. These
include control strategy conclusions as well as findings which have resulted
from the technical support analyses. Some of the limitations inherent in the
study are discussed, and areas for future work are briefly described.
1.1 BASIC DEFINITIONS
Suspended particulate air pollution in Los Angeles is an extremely
complex phenomenon. Before embarking on a control study for this air
pollution system, it is useful to establish agreement on terminology. This
section provides definitions for several basic terms that appear frequently
in this report.
In this study, suspended particulates and aerosol are used inter-
changeably. Both refer to suspended particles, (liquid or solid), in air.
1-3
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The basic measuring unit used herein is total aerosol mass concentration,
(pg/m3); thus, the details of the particle size distribution are usually
neglected.
One very important distinction that is made involves the concept of
primary particulates versus secondary particu1ates, (or alternatively primary
aerosol versus secondary aerosol).* Primary aerosols are directly emitted;
they enter the atmosphere as particles. Secondary particulates are formed
in the atmosphere from the conversion of gases to particles by chemical re-
action processes. The four principal types of secondary aerosol are sulfate
(SO^), nitrate (NOZ), ammonium (NHt), and secondary organics. The gaseous
precursors of these aerosols are sulfur dioxide (S0«), nitrogen oxides (NO ),
£ X
ammonia (NhL), and reactive hydrocarbons (RHC), respectively.
A distinction is sometimes made here, (see Section 2.1.1 or Support
Document #1), between ambient total suspended particulates and Hi-Vol total
suspended particulates. The former refers to total particulate mass loading
in the atmosphere, while the latter refers to the mass loading which is
measured by a Hi-Vol monitor. As discussed in Section 2.1.1, Hi-Vol measure-
ments are sometimes not fully representative of ambient conditions.
A third distinction involves the concept of background particulates
versus non-background particulates. For the purposes of this study, non-
background aerosol is defined as that which is subject to direct emission
regulations in the Metropolitan Los Angeles Region. Conversely, background
aerosol consists of the part which is non-controllable by direct emission
*The reader should not confuse this concept with the terms "primary" and
secondary" standards. The national primary and secondary standards refer
to the different target levels for total particulate air quality, i.e.
each standard applies to the sum of both primary and secondary aerosol.
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regulations in Los Angeles. In this sense, there are three main background
aerosol sources: natural sources, suspended soil dust from man-related
activities such as traffic or agriculture, and anthropogenic* sources
exterior to the Metropolitan Los Angeles Region. This definition of back-
ground source differs from the more common usage which refers to natural
sources only.
In formulating control plans, it is useful to distinguish between
control measures and control strategies. Herein, a control measure refers
to a specific emission reduction technique applied to a certain source or
group of sources. A control strategy consists of a collection of various
control measures along with a timetable for implementation. Thus, the
distinction between Chapters 3 and 4 of this report is that the former pro-
vides documentation on alternative control measures while the latter selects
various combinations of these measures to formulate control strategy scenarios.
1.2 LIMITATIONS IN THE SCOPE OF THE STUDY
Limits in the allocated level of effort necessitated the establish-
ment of certain bounds for this study. Countless decisions were made
during the course of the project as to the depth of pursuit for various
problems and issues. Some of the major limitations in study scope are
discussed briefly below.
Study Region: The 4-County Sub-Area
As shown in Figure 1-1, the Metropolitan Los Angeles Air Quality Control
Region includes all of Orange and Ventura Counties and portions of Los Angeles,
Riverside, San Bernardino, and Santa Barbara Counties. During the course of
this study, it was found that suspended particulate levels in Ventura and
*Man-made
1-5
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SANTA
BARBARA
Location Of
Basin
N
Figure 1-1 Metropolitan Los Angeles Air Quality Control Region
1-6
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Santa Barbara Counties are generally much lower than levels found in the
other four counties, (the 4-County Sub-Area). The highest annual readings
in Ventura and Santa Barbara Counties are very close to the primary national
o
standard for suspended particulates, (75 pg/m AGM), while the highest read-
ings in the other four counties are well in excess of that standard sometimes
by a factor of two or more. Also, the overall emission and meteorological
patterns in the Los Angeles Region support the conclusion that sources in
Ventura and Santa Barbara Counties have negligible impact on overall air
quality levels in the 4-County Sub-Area. In an air quality sense, the 4-
County Sub-Area can be viewed as a distinct entity within the entire air
basin. In this study it was decided to focus on the 4-County Sub-Area in
formulating and evaluating control strategies.
Annual Versus 24-Hour Standards
Federal air quality standards for suspended particulates have been
established for both long term (annual geometric mean) and short term
(24-hour maximum) concentrations. However, in evaluating the impact of
control strategies on air quality, this study focuses only on the annual
levels. There are two basic reasons for this restriction in scope.
First, analyses performed in this study indicate that the annual standards
are the binding constraints for the Los Angeles Region. Attainment of the
annual standards apparently implies concurrent attainment of the 24-hour
standards. Second, it was found that existing aerometric data could not
1-7
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support a sound emission level/air quality model for 24-hour concentrations.
In contrast, data were sufficient to allow a systematic model for annual
particulate levels. A detailed discussion of these .two reasons can be
found in Section 2.1 of Support Document #3 to this study.
Strategy Time Frame and Base Year Selection
As called for by contractual arrangements with the Environmental
Protection Agency, this study evaluates control strategies for the years
1977 and 1980. Although quantitative analyses are not carried out for post
1980, some of the qualitative long term differences between alternative
strategies are discussed.
The base year for the study is 1972. This choice is convenient in the
sense that it is the most recent year for which both extensive emission
and air quality data are available. The base year emission data are
used as the foundation for emission forecasts to 1977 and 1980. Both the
emission and air quality data for the base year are important as calibration
parameters for an air-quality/emission-level model.
It should be noted that this report treats base year air quality in a
statistical sense. "Expected" 1972 air quality levels are determined from
the statistical distribution of particulate levels based on two years of
data (7/71-6/73) and from a comparison of these results to several more
years of data. These expected levels, rather than actually measured 1972
levels, are used to characterize air quality for the base year. This help<,
to avoid the pitfall of calibrating the air quality model with an anom-
alous measured air quality value which may have occurred in the base year.
Particulate S-ize Distribution and Chemical Composition
The objective of this study is to investigate control strategies for
1-8
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approaching and/or attaining the national air quality standards for particu-
i
lates. These standards are specified in terms of the total mass concentra-
tion of suspended particulates, (yg/m ). The usage of only total mass con-
centration neglects the size distribution and chemical composition of parti-
culate matter. The particulate size distribution is a very important factor
for public health and visibility considerations. Light scattering is much
more efficiently produced by particles in the .1 to 1 micron size range
than by an equivalent mass of particles outside that range. Sub-micron
particles have also been shown to be relatively more deleterious to pulmonary
health than larger particles. The chemical pomposition of particulates,
(e.g. sulfate, lead, asbestos, etc.), is also a very important factor in
health effects .
The only parts of this study which treat particle size distribution
in a specific and quantitative way are the emission inventory and control
effectiveness analyses for primary particulates. In the inventory, emitted
total particulates are distinguished from emitted suspended particulates.
The distinction is based on a particle diameter of 10 microns, (only those
smaller than 10 microns are considered as suspended). The efficiency of
various control measures for primary particulate emissions are also computed
separately for total andvfor suspended emissions. The emissions and control
data for suspended particulates are used in calculating air quality changes
resulting from emission level changes.
The chemical composition of particulate matter is considered here in
order to formulate an air quality model for suspended particulates. Changes
in air quality levels are computed separately for sulfates, nitrates,
ammonia, secondary organics, and primary particulates.* The complete change
*Data are also available in this study for determining the effect of lead
emissions on suspended lead air quality.
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in suspended particulate air quality is calculated by summing the changes
for the individual categories. Since this study is concerned with the
existing national standards, only the results for total suspended particulate
air quality are presented. One exception is made in Chapter 5, where the
impacts of alternative strategies on sulfate levels are also briefly
discussed.
1.3 SUMMARY OF CONCLUSIONS AND RECOMMENDATIONS:
Chapter 5 of this report presents the conclusions and recommendations
that have resulted from this investigation. For summary and emphasis, the
most significant points are listed below.
Conclusions:
For the purpose of control strategy formulation, at least
three general sub-areas of the Los Angeles Region have been
identified, each with different maximal suspended particulate
levels, (the maximum among the monitoring sites in those
areas). These are 1) Ventura and Santa Barbara Counties
(presently just above the national primary standard), 2) the
Four-County Area except Area 3 below (presently at about
twice the national primary standard), and 3), the Western
San Bernardino County Hot-Spot (presently at about three
times the national primary standard).
Eight process categories account for more than 97% of
primary suspended particulate, S09,NO , and RHC emissions
c. X
in the Los Angeles Region. They are stationary fuel com-
bustion, motor vehicles, the petroleum industry, aircraft,
the chemical industry, metallurgical processes, organic
solvent use, and mineral processes. The first four
categories are especially significant. Motor vehicles
are the major source of RHC and NO emissions in the 1972
j\
base year inventory. Motor vehicles, stationary fuel
combustion, and aircraft account for most of the suspended
particulate emissions. Stationary fuel combustion, chemical
1-10
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processes, petroleum refineries, and motor vehicles,
respectively are the most important sources of SO^.
The forecasted substitution of fuel oil for natural
gas in stationary combustion sources and the scheduled
controls for motor vehicles are the two most significant
factors affecting emission projections for 1977 and 1980
in the Los Angeles Region. Due to the increased use of
fuel oil, basin-wide emissions of suspended particulates,
S0? and NO will increase from 1972 to 1977 with present
£ A
control policies. The motor vehicle control program will
significantly reduce regional RHC emissions in 1977 and
1980, especially if the EPA oxidant implementation plan
is implemented. Around the middle of the decade, motor
vehicle controls will reverse the upward trend in
regional NO emissions. The combined effect of these
/\
emission trends leads to very slight changes in air
quality from 1972 to 1977 and 1980. Suspended parti-
'culate levels are forecasted to increase marginally
at most locations; however, a few sites will experience
minor improvements in air quality.
Existing data indicate that background (noncontrollable)
3
particulate levels are around 30-40 ;ug/m AAM in the
coastal areas of the Los Angeles Region. Background
aerosol levels apparently increase with distance inland
to about 45-60 -ug/m AAM in the eastern-inland parts of
the region. The existence of substantial background levels
limits the air quality effectiveness of emission controls
in the Los Angeles Region; a very high degree of control for
man-made sources will be required to attain the national
air quality standards.
Non-background primary particulate contributions generally
tend to be highest in the coastal and central-valley areas
of the Los Angeles Region. The one exception involves the
Western San Bernardino County Hot-Spot (Chino-Rialto) which
1-11
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is apparently influenced by the Kaiser Steel/Edison
Electric complex. Sulfate levels tend to be uniformly
distributed over the basin at around 10-:15/jg/itr AAM,
(again the Hot-Spot is an exception). Measured nitrate
and estimated secondary organic levels tend to increase
considerably with distance inland. The combined effect
of background and non-background spatial patterns is a
slight general increase in total suspended particulates
with distance inland. The above spatial air quality trends
are consistent with known aspects of emission source
distribution, meteorology, and atmospheric chemistry.
The federal and state motor vehicle controls and the
county APCD stationary source programs have achieved
substantial overall levels of control for primary parti-
culates and gaseous precursors of secondary particulates
in the Los Angeles Region. The most significant additional
technological control alternatives for primary suspended
particulates are motor vehicle particulate traps, fabric
filters, electrostatic precipitators, and alternative
fuels (e.g. methanol). The major additional control
possibilities for SCL are desulfurization of petroleum
products to very low sulfur levels, SCL removal processes
for exhaust gases, and alternative fuels, For further
NO control, modifications of combustion processes and
f\
alternative fuels are the principal control measures.
The EPA oxidant plan appears to incorporate all the major
additional RHC control options that are presently implemen-
table. Non-technological control options include growth
restrictions, relocations, and source usage measures (e.g.
conservation policies or transportation controls).
Application of the most effective technological controls
which have been identified in this study will attain
overall reductions of 59%, 86%, and 22% (for primary
suspended particulates, S09, and NO respectively) from
( A
1-12
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projected 1977 levels. Since emissions of each pollutant
are projected to increase from 1972 to 1977, the overall
reductions in 1977 from 1972 levels are only 49%, 83%, and
6% respectively. The EPA oxidant plan will achieve a 51%
reduction in RHC levels from 1972 to 1977.
Recommendations:
A strategy to attain the national primary standards for
suspended-particulates in the Los Angeles Region would
involve severe non-technological controls in addition to
the maximum degree of technological control available from
measures considered in this study. The overall degree
of non-technological control required would be equivalent
to 75% relocation of aircraft activity, power plants,
refineries, and major industrial sources plus a 50%
reduction in motor vehicle traffic. Because of the great
socio-economic disruptions and implementation problems
involved, the standard attainment strategy is not recommended
as a viable basis for air quality control policy in the 1970's.
Two alternative technological control strategies are
recommended as options for suspended particulate air quality
policy in the 1970's. One is based on desulfurization of
fuels plus add-on devices for various sources. The second
is a delayed scenario emphasizing methanol conversion for
stationary combustion sources plus add-on devices for other
sources. Although neither strategy will produce standard
attainment at all locations by 1980, significant air
quality improvements are attained by each. The annualized
cost for the strategies is about $230 million per year. The
methanol strategy leads to a three year delay in air quality
improvement and entails greater implementation problems;
however, we find a slight preference for it based on long
term advantages for air quality and energy considerations.
In general, long term strategies seem more appropriate than
1-13
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shorter term approaches due to the expected long term
nature of the particulate air quality problem in the
Los Angeles Region.
It is recommended that growth restrictions, energy
conservation measures, and transportation controls be
given further study. Appropriate non-technological
controls should be combined with the proposed technological
strategies to form a more comprehensive air quality control
plan.
The particulate air pollution problem in the Los Angeles
Region will be aggravated by the forecasted substitution
of fuel oil for natural gas in stationary combustion
sources. It is recommended that national allocation of
clean fuels, such as natural gas, be performed with strong
consideration given to relative air quality impacts in
various regions.
The technical support analyses for this study encountered
many areas of uncertainty due to inadequacies in existing
data. Recommendations for future work to help reduce
these uncertainties are made in Chapter 5 of this study.
1-14
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2.0 BASIC TECHNICAL BACKGROUND INFORMATION
The purpose of the present study is to formulate an implementation
plan for the control of suspended particulates in the Metropolitan Los
Angeles Air Quality Control Region for the years 1977 and 1980. In order
to formulate this plan, certain preliminary analyses are required which
serve as basic technical supports for the study. First, existing air
monitoring data must be analyzed so that base year (1972) particulate air
quality can be characterized for the Los Angeles Region. This character-
ization establishes the overall scope of the problem and helps to identify
sub-areas of the region for the purpose of control strategy formulation.
Second, emission inventories and projections must be compiled for primary
suspended particulates as well as for the gaseous precursors of secondary
particulates. The 1972 base year emission inventories and the 1972 air
quality characterization serve as the fundamental calibration parameters
for an air-quality/emission-level model. The emission projections to 1977
and 1980 are for the existing or nominal control policy; the control
strategies proposed later will be applied to this projected inventory.
Finally, a model must be formulated which can translate emission level
changes into air quality changes. This model is used to project air quality
for the existing or nominal control policy and later to determine the air
quality impact of the control strategies proposed in the implementation
plan.
The above three preliminary studies have been performed as described
in the first three Support Documents to this report, [1],[2],[3].
This chapter serves to summarize the results. Section 2.1 deals with the
analysis of particulate air monitoring data. Section 2.2 presents the
2-1
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emission inventories and projections. In Section 2.3, a model is des-
cribed for determining the air quality impact of emission level changes.
2.1 ANALYSIS OF AIR MONITORING DATA
The first preliminary technical study, (Support Document #1), con-
sists of an analysis of Hi-Vol monitoring data for the Metropolitan Los
Angeles Region. The main objective of this analysis is to characterize
particulate levels in the Los Angeles Region for the 1972 base year.
This characterization is presented below in Section 2.1.3.
In using ambient measurements to characterize air quality, it is
important to know what those measurements represent and how they were
taken. This helps to establish error bounds for the air quality character-
ization. Accordingly, two sub-objectives of the air monitoring data
analysis are to review the Hi-Vol monitoring method in general, and to re-
view the procedures of Los Angeles Region monitoring programs in particu-
lar. These reviews are presented in Sections 2.1.1 and 2.1.2 below.
2.1.1 Review of the Hi-Vol Sampling Method
The National Ambient Air Quality Standards for suspended
particulates specify Hi-Vol sampling as the appropriate monitoring tech-
nique. The official procedure is published in the Federal Register,
[b]. Comprehensive descriptions of the Hi-Vol monitoring technique
are found in References [6] and [7].
A Hi-Vol sampler (illustrated in Figure 2-1) consists of a
covered housing, a filter holder assembly, a vacuum sweeper motor, and
a flow meter. Sampling with a Hi-Vol basically consists of weighing
a preconditioned (temperature and humidity) filter pad, drawing air
through the pad for a given time (usually 24 hours), recording the
initial and final flow rates, and reweighing the pad (again after con-
2-2
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Housing
Filter
Surface
Figure 2-1 Hi-Volume Sampler and Shelter
ditioning to set humidity and temperature). The average concentration
of total suspended particulates is calculated by dividing the weight
gain of the filter pad by the total volume of air sampled.
Hi-Vol filters generally provide a very efficient means of
entrapping samples of suspended particulates. The filter fibers tend
to intercept larger particles (>1 Micron) by mechanical action and
smaller ones (<0.1 Micron) by Brownian motion. A minimum in collection
efficiency is observed in the 0.1 to 1 Micron range. However, the
EPA reference procedure calls for filter standardization to achieve
99% collection efficiency at a nominal particle diameter of 0.3 Microns
This level of collection in the range of minimal efficiency insures
an extremely high overall entrapment efficiency.
The high level of collection efficiency does not insure that
Hi-Vol samples accurately represent ambient particulates. Factors
2-3
-------
other than entrapment efficiency are important. Volatile liquid aerosols
can be lost during the sampling and analysis procedures, leading to an
underestimate of true, ambient aerosol mass. Gaseous pollutants,
particularly SOp and NO^ can be adsorbed on the filter, leading to an
overestimate. Measurement techniques for air volume and mass deposit
are also potential sources of inaccuracy. As will be discussed below,
the importance of these various factors depends on the nature of the
test atmosphere and on the specific monitoring procedures which are
practiced. However, in terms of a gross generalization, the potential
error in a Hi-Vol measurement typically appears to be on the order of
10 to 20%.
Fa'ctors Affecting Hi-Vol Accuracy
Aspects of Hi-Vol monitoring practice which affect sampling
accuracy are the choice of_ fil ter media, equil ibriating procedures,
flow measurement techniques, calibration procedures, and weight and
time measurements. These will be discussed very briefly here. A more
detailed treatment can be found in Support Document #1 to this study,
[1].
Routinely, Hi-Vol sampling is performed with glass fiber
filters. The principal advantages are; high collection efficiency,
low flow resistance, and low tendency to plug under heavy loading. One
disadvantage is that some alkalinity may be associated with the glass,
resulting in adsorption of acid gases such as S0~ and N0? and leading
to an apparent increase in measured particulate loading. The magni-
tude of this error depends on the chemical nature of the test atmosphere.
2-4
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To mini mize this effect, acid washed filters are preferred.
To obtain reproducible results with Hi-Vol samples, weighing
of filter pads is performed after conditioning at controlled humidity
and temperature. The standard equil ibriating procedures call for 50%
RH and 20°C. Present evidence indicates that equilibrated Hi-Vol data
reflect only trace amounts of water, [8], [9]. This apparently
represents an understatement of ambient loadings which can contain
water fractions of 10-20%, or more, [10] . Volatile organic
material associated with the participate phase also may evaporate between
sampling and weighing, [11], [12]. The magnitude of this effect de-
pends on the amount of organic material present, but the typical im-
pact on total measured particulate mass should not exceed a couple
percent, [11]. A short delay between sampling and weighing will help
to reduce this source of error.
Flow measurement techniques and flow meter calibration pro-
cedures are important factors in the precision of Hi-Vol measurements.
With the continuous flow measurement technique and with frequent
calibrations, the accuracy of flow measurements should be about - 5%,
[11], [13]. Using an average of initial and final flow readings or
performing infrequent calibrations can increase the potential error by
a factor of 2 or more.
Weight and time measurement techniques are a relatively
small source of error in Hi-Vol data. The uncertainty in these tech-
niques is typically less than - 1%.
Reproducibility of Hi-Vol Measurements
Investigators have examined the overall reproducibility of
2-5
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Hi-Vol measurements under a variety of operating conditions, [7], [14],
[15], [16], [17], [18]. These studies suggest that, for-given monitor-
ing procedures, the reproducibility of Hi-Vol measurements varies from
about - 2% under carefully controlled conditions to about * 6% under
actual field conditions. It should be remembered, however, that repro-
ducibility does not necessarily represent accuracy. As noted above,
Hi-Vol monitoring procedures can contain built-in biases which result
in consistent underestimates or overestimates of ambient aerosol loadings,
Chemical Analysis Procedures
After Hi-Vol samples have been weighed to determine total
aerosol mass, the filters can be divided up for analysis of metals,
inorganic ions, and/or organic material. Support Document #1 to this
study describes some of the chemical analysis procedures involved. It
appears that current methods for metals and inorganic ions are generally
appropriate; the precision of these methods is around - 10%.* In con-
trast, the common analysis procedures for organics are notably deficient.
Measurements of organic aerosol content typically consist of data on
benzene solubles, (or sometimes cyclohexane solubles). Benzene and
cyclohexane are fairly efficient for extracting primary organic aerosol,
e.g., the tarry particles emitted in auto exhaust. However, both sol-
vents are very inefficient for highly oxidized secondary organic com-
pounds; possibly 30% or less of the secondary organic aerosol is
* A notable exception involves some lead data determined by the "ash
procedure". Before the ash procedure was standardized, values for
lead were often 50% or more low due to excessive temperature and baking
time.
2-6
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extracted, [19], [20]. For areas like Los Angeles, where secondary
organic aerosol contributions are very significant, benzene or cyclo-
hexane solubles provide a poor measure of organic particulate levels.
Hi-Vol Sampler Location
Hi-Vol measurements are sensitive to the details of sampler
location. Since larger particles have a lower probability of being
transported to higher elevations, total particulate loading tends to
decrease with height. The proximity to local sources, such as traffic,
also has a strong affect on measured particulate levels. Recent data
taken in Los Angeles indicate about a 20% decrease in Hi-Vol measure-
ments from an elevation of 20 feet to an elevation of 90 feet, [l ].
Several guidelines are pertinent to Hi-Vol sampler location
e Hi-Vol sampling should be performed at 50
feet or less above ground in order to represent
prime human exposure areas .
e Samplers should be located away from direct
influence by local particulate sources.
Pairs of Hi-Vols should be several feet apart
to avoid sampling each other's exhaust.
The exhaust should be two or more feet above
ground to avoid stirring up ground dust.
o Sampling should be done away from a wall to
allow representative air to pass over the mon-
itor.
Compliance with these guidelines should be checked when using Hi-Vol
data for air quality analysis.
2-7
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2.1.2 Review of Monitoring Programs in the Los Angeles Region
There are three major sources of Hi-Vol data in the Metro-
politan Los Angeles Region: the Air Pollution Control Districts (APCD's),
the National Air Surveillance Network (NASN), and the Community Health
Environmental Surveillance System (CHESS). The APCD's are county agencies,
while NASN and CHESS are federal programs. Table 2-1 summarizes the
number of sampling sites and the sampling frequency for each of the
monitoring programs. Figure 2-2 illustrates the location of the Hi-Vol
sites within the Los Angeles Region.*
TABLE 2-1 SAMPLING SITES AND SAMPLING FREQUENCY OF THE APCD, NASN, AND
CHESS MONITORING PROGRAMS IN THE LOS ANGELES REGION
MONITORING
PROGRAM
County APCD's
.os Angeles
Drange
San Bernardino
Riverside
i/entura
Santa Barbara
Total - APCD's
WSN
CHESS ;
NUMBER OF
SAMPLING SITES
6
3
7
1
10
1
28
11
6
SAMPLING
FREQUENCY \
~70 per year
~90 per year
~60 per year
~70 per year
~60 per year
~60 per year
60 - 90 per year
~24 per year ;
daily
* The addresses of the sampling sites are presented in Support Docu
ment #1 to this study, [ 1 ].
2-8
-------
ro
Co
Figure 2-2. APCD, NASN, and CHESS Hi-Vol Sites in the
Metropolitan Los Angeles Region
-------
Comparison of Monitoring Procedures
Support Document #1 reviews the specific Hi-Vol monitoring
procedures of the APCD, NASN, and CHESS programs, [1 ]. As discussed
later in Section 2.1.3, this review is useful in deciding what data
to rely on in characterizing air quality levels in the Los Angeles
Region. Some of the more significant results of the monitoring program
review can be summarized as follows:
Sampling in the CHESS program is performed
daily. Sampling frequencies of the various .
county APCD's range from every fourth to
every ninth day. NASN Hi-Vol measurements
are taken only about twice a month.
Non-acid washed glass fiber filters are used
in each monitoring program. Equilibriation
at 20°C and 50% RH is performed by all agencies
except the Ventura County APCD. All agencies
except the Los Angeles County APCD use the
orifice plate calibration method.
9 Uniform sampler positioning guidelines do
not appear to have been enforced in either the
NASN or APCD programs. NASN and APCD samplers
are at heights varying from ground level to about
100 feet, but most of the APCD monitors are at
10-30 feet elevations.
CHESS monitors tend to be located in quiet areas
such as suburban school yards. NASN stations in
Los Angeles generally represent downtown commercial
areas. Most APCD monitors are also in commercial
areas.
The most extensive data on Hi-Vol chemical compo-
sition are provided by the NASN, Los Anaeles APCD,
2-10
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and San Bernardino APCD programs. The Ventura,
Orange, Riverside, and Santa Barbara APCD's take
either no composition data or data on lead only.
Comparison of Measured Hi-Vol Levels
Table 2-2 provides an overall comparison of APCD, NASN, and
CHESS measurements for total suspended particulates in the Los Angeles
Region. The available annual geometric means (AGM's) are given for
1967 through 1973. The main point emphasized by Table 2-2 is that
the CHESS values are considerably lower than APCD or NASN values in
each of the three counties with CHESS stations. For instance, Los
3
Angeles County data typically fall in the range of 75-155 ju.g/m for APCD
samples and 75-130/jg/m for NASN samples. However, CHESS data in Los
3
Angeles county are in the range of 50-100 /jg/m . The apparent reason
for this discrepancy is that the CHESS data represent residential
areas rather than prime exposure areas. CHESS sites have been chosen
for a health study involving school children, end, as discussed above,
they are located in quiet suburban areas, [21].
The overall Hi-Vol levels measured by the NASN and APCD pro-
grams appear to be generally in line with one another. To examine the
question of agreement more rigorously, statistical "t" tests were per-
formed for five locations where NASN and APCD monitors have been main-
tained within a few years of one another. Table 2-3 summarizes
the results. County APCD data are slightly higher than NASN data at
Riverside, San Bernardino, and Ontario, but the differences are not
statistically significant to 95%. At Anaheim, APCD data are lower
2-11
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TABLE 2-2
APCD, NASN, AND CHESS ANNUAL HI-VOL LEVELS, AGM'S FOR 1967
COUNTY APCD STATIONS
- 1973
County
Los Angeles
Riverside
San Bernardino
Orange
Ventura
Santa Barbara
Station
Central LA
Lennox
U.Los Angeles
W.San Fernando
Valley (Reseda)
Azusa
Pasadena
Riverside
San Bernardino
Ontario
Redlands
Fontana
Rial to
Chino
Upland
Anaheim
La Ha bra
Costa Mesa
Oxnard
OJai
Santa Paula
Ventura
Camari llo
Port Hueneme
Simi Valley
Moore Park
Pt. Mugu
Thousand Oaks
Santa Barbara
1973
114
124
74
103
121
101
135D
85
S3
89
111
153
118B
127
98
113
66
77
66
67
73
80
106
74
62
58
81
HA
1972
130
137
86
143
150
110
140°
108
110
96
136
170
194
-
105
120
67
77
66
76
66
73
97
-
-
-
66
1971 1970
162 136
154 144
85 91
115 112
138C -
106C -
(136°) -
117 119
111 107
94 102
100 NA
130 139
178 NA
-
85 95
114
-
71 64
73
-
69 51
90
-
-
65
60
1969 1968 1967
154 157 145
150 148 139
99 92 71
117 109 135
-
.
.
91 121 123
134 151 122
94 95 133
NA NA 109
NA 151 NA
172 163 144
111
105 95 NA
-
-
-
-
.
.
.
- '
92
-
NASN STATIONS
CHESS STATIONS
A California ARB Data
B Station Moved from Airport to Downtown Chino after 1972
C Represents July to December only
D Calculated from raw data of Riverside APCD
E 3 Quarters Only
.OS Angeles
Overside
San Bernardino
Orange
Central LA
Pasadena
Burbank
Glendale
Long Beach
Torrance
Riverside
San Bernardino
Ontario
Anaheim
Santa Ana
NA
NA
NA
NA
NA
NA
NA
HA
NA
NA
HA
120
90
117
95
96
73
114E
135
117
103
96
133
100
131
85
87
88
120
104
111
116
140
125
111
123
87
95
86
119
118
116
114
127
93
90
88
74
104
68
124
95
109
93
123
129
106
103
90
114
-
116
92
116
95
91
-
75
118
-
-
.
-
Los Angeles
)range
Ventura
Santa Monica
Glendora
West Covina
Anaheim
Garden Grove
Thousand Oaks
67
48
64
67
63
35
69 -
97
99
87
80
59
-
.
.
-
-
-
2-12
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than NASN data, and the difference is just over 95% significant. At
Central Los Angeles, APCD data are much higher than NASN data and the
results are very significant on a statistical basis. As discussed in
Support Document #1, the discrepancy at Anaheim may best be assigned to
less frequent calibration of the NASN samplers, [22]. The one very
large discrepancy, at Central Los Angeles, may be due to differences
in calibration procedures and/or to a higher operating flow rate for
the NASN Hi-Vol. [9 ].
TABLE 2-3 EQUIVALENCY
LOCATION
Central Los Angeles
Riverside
San Bernardino
Ontario
Anaheim
TESTS FOR APCD
YEARS OF
DATA
1967-1972
1970-1971
1968-1972
1968-1972
1969-1972
AND NASN
HI-VOL GEOMETRIC
GEO. MEANJ.EVELS
APCD NASN
147
136
111
121
97
114
121
108
114
106
MEANS
"t" VALUE
6.5
1.6
0.5
1.1
2.1
NOTE: t = 1.98 for 95% confidence of a statistical difference in the
respective data
2.1.3 Characterization of Hi-Vol Levels in the Los Angeles Region
for the 1972 Base Year
The main objective of the present section, ANALYSIS OF HI-VOL AIR
MONITORING DATA, is to characterize Hi-Vol air quality in the Los Angeles
Region for the 1972 base year. This characterization will provide a
systematic comparison of present Hi-Vol levels at various locations in
the Los Angeles Region to the National Ambient Air Quality Standards
for particulates, (presented in Table 2-4). The comparison will be used
here to define sub-areas of the Los Angeles Region for the purpose of
2-13
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control strategy formulation. Later, in Section 2.3, the 1972 air
quality characterization will serve as a fundamental calibration input
for an air-quality/emission-level model for particulates in the Los
Angeles Region.
TABLE 2-4 THE NATIONAL AMBIENT AIR QUALITY
STANDARDS FOR PARTICULATES
Annual
Geometric
Mean
Maximum: Not to
be exceeded more than
once a year
PRIMARY STANDARD
SECONDARY STANDARD
75 ug/nf
f
60 ug/nT
260 ug/m for 24 hours
3
150 ug/m for 24 hours
*Target level for achievement of the secondary 24 hour standard
Policies for Data Analysis
In characterizing present Hi-Vol levels for Los Angeles, two main
policy issues arose concerning data analysis. The first issue involves
the question of which data set to emphasize, i.e., APCD data vs. NASN
data vs. CHESS data. As noted in the previous section, these data sets
are not totally consistent. The decision was made to rely basically
on APCD data, using NASN and CHESS data as supports where appropriate.
The reasons for emphasizing APCD data are summarized below:
t CHESS data tend to represent "clean urban" areas and are
considerably lower than APCD data which in many cases re-
present "prime exposure" areas. The use of APCD data will
provide a more conservative comparison of present air quality
to the air quality standards. The addition of the 6 CHESS
sites to the 28 APCD sites adds no further binding constraints
in designing control strategies to meet the air quality
standards.
2-14
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APCD samples are taken more frequently than NASN samples; thus,
they provide a better statistical data base. APCD Hi-Vols are
usually standardized more frequently than NASN samplers.
There is a shorter time period between sampling and weighing
for APCD samples. Also, several NASN sites are higher above
ground than recommended.
For the areas with the highest Hi-Vol recordings, APCD results
appear to be somewhat higher than NASN results, (although the
difference is statistically very significant only at Central
Los Angeles). The addition of 11 NASN sites to the 28 APCD
sites adds no further constraints on the degree of reduction
required by control strategies in order to attain the NAAQS.
The second issue involves the statistical treatment of the data.
In many previous implementation plans for various pollutants, base year
air quality has simply been taken as the air quality level actually
measured in the base year, e.g., the actual annual average or actual
one day maximum that occurred in the base year. Unfortunately, an anom-
alous value in the base year can have pronounced effects on the degree
of control required in the implementation plan. With APCD Hi-Vol data,
the potential for a very uncharacteristic value to occur in any given
year is significant; sampling is performed only 60-90 days per
year and the standard deviations of the measured annual geometric means
are +_ 10 to 15%.
To account for the stochastic nature of air quality levels, it
was decided in this study to perform a statistical examination of Hi-
Vol levels in the Los Angeles region. The basic statistical tool in-
volved the use of "log-probability" paper. The techniques which were
used are explained in detail in Support Document #1, [l]. Basically,
Hi-Vol data were plotted on log probability paper and straight lines,
(log normal distributions), were fitted to the data. The expected
2-15
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annual geometric mean and expected 24 hour maximal values were calculated
from these distributions.
To augment the amount of data for determining the 1972 base year
Hi-Vol distributions, measurements were used for the period of July
1971 to June 1973, (2 years of data).* The distributions were determined
for the 15 APCD monitoring sites listed in Table 2-5. The two main
criteria in selecting these sites were that they be scattered through-
out the air basin and that they be the sites with maximal Hi-Vol levels
for the particular sub-area which they represented. The log-normal
plots and relevant statistical parameters for each of the 15 Hi-Vol
sites are presented in Support Document #1 .
Expected Annual Geometric Means for the 1972 Base Year
Figure 2-3 presents the expected annual geometric mean Hi-Vol levels
for the 1972 base year at the 15 APCD monitoring sites listed in Table
2-5. As noted above, these expected AGM'S have been calculated from
statistical distributions based on data from 7/71 to 6/73.
To check that the period from 7/71 to 6/73 was not an extremely un-
usual meteorological period for Hi-Vol geometric means, the calculated
values were compared to historical AGM'S (from 1967-1973) in Support
Document #1, [1]. This check indicated that the values in Figure 2-3
were generally in agreement with the historical record. **
*For two locations, slightly different periods were used because
the monitoring sites were changed during 7/71 to 6/73. See Support
Document #1 for details, [Ij.
** The only notable exceptions were that the Reseda (and possibly Azusa)
value might be about 10% higher than for average meteorology and the
Central Los Angeles value might be about 10-15% lower than for
average meteorology.
2-16
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TABLE 2-5 MONITORING SITES FOR THE 1972 BASE
YEAR AIR QUALITY CHARACTERIZATION
LOS ANGELES COUNTY
ORANGE COUNTY
San Bernardino County
Riverside County
VENTURA COUNTY
SANTA BARBARA COUNTY
Lennox
Central Los Angeles
Reseda
West Los Angeles
Pasadena
Azusa
La Habra
Anaheim
San Bernardino
Ontario
Chi no
Rial to
Ri vers ide/Rubi odoux
Oxnard
Santa Barbara
2-17
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ro
i
CO
Figure 2-3. Expected Annual Geometric Mean Hi-Vol Levels
for the 1972 Base Year
-------
Expected Maximal 24 Hour Levels for the 1972 Base Year
Figure 2-4 presents the expected maximal 24 hour levels for the
1972 base year at the 15 monitoring sites. These expected measured
maxima have been calculated from the statistical distributions for the
present APCD monitoring frequency (60 to 90 days per year). The expected
actual maxima (assuming monitoring was done every day) would be higher
than these values; Table 2-6 illustrates this difference.
In Support Document #1, the values in Figure 2-4 were compared
to the historical APCD record of maximal 24 hour levels for the years
1967 to 1973. This served as a check against the possibility that
the 7/71 to 6/73 period was meteorologically unusual. The historical
record tended to confirm the calculated 24 hour max values, with the
exception that the calculated values in Los Angeles County were about
10% lower than typical historical maxima in that county. Possible
reasons for this discrepancy are discussed in the Support Document.
Analyses were also made of Hi-Vol seasonal patterns at various loca-
tions and of the meteorology associated with maximal Hi-Vol levels. It
was found that Hi-Vol levels in the western-coastal area are greatest
during the winter, on days associated with high values of primary
contaminants such as CO. In the eastern-inland area, of the Los Angeles
Region, Hi-Vol levels are greatest during the summer-fall photochemical
smog season. These findings are qualitatively consistent with known
facts about particulate origins, meteorology, and pollution distributions
in the Los Angeles region. The Los Angeles aerosol is composed of both
primary particulate (directly emitted) and secondary particulate (formed
in the atmosphere by chemical-physical processes). The primary and
secondary sources are of the same order of magnitude, (see Section 2.3).
2-19
-------
ro
ro
o
I
Figure 2-4. Expected 24-Hour Max. Hi-Vol Levels for the 1972 Base Year
(for the present APCD Monitoring Frequency)
-------
TABLE 2-6 EXPECTED MEASURED 24 HOUR MAXIMA vs. EXPECTED
ACTUAL 24 HOUR MAXIMA FOR HI-VOL MONITORING
SITES IN THE LOS ANGELES REGION
MONITORING
SITE
L. A.
COUNTY
ORANGE
COUNTY
SAN BERN.
COUNTY
RIVERSIDE
COUNTY
VENTURA
COUNTY
SANTA BARB.
COUNTY
Lennox
Central Los Angeles
Reseda
West Los Angeles
Pasadena
Azusa
Anaheim
La Habra
San Bernardino
Ontario
Chi no
Ri al to
Riverside
Oxnard
Santa
Barbara
C70
EXPECTED MEASURED 24
HR. MAX. AT PRESENT
MONITORING, FREQUENCY
Gug/nr)
290
336
356
172
210
323
240
360
411
275
710
550
470
166
164
C365
EXPECTED ACTUAL 24
HR. MAX. ASSUMING
DAILY MONITORING
(jug/tir)
340
414
446
200
247
380
290
460
540
360
1000
780
620
200
200
2-21
-------
Now, it is known that primary contaminants (e.g., CO) reach maximal
levels in the western-coastal area of the basin and that the highest
values occur in the winter. It is also known that photochemical smog,
a principle source of secondary contaminants, is most intense in the
eastern-inland portions of the basin and that summer-fall is the "in-
season" for photochemical pollution. The high winter values for suspended
particulatesin the western-coastal area during the winter appear to
reflect the importance of primary aerosol, (particularly to the
western area). The high summer-fall values for particulates in the
eastern-inland area seem to reflect the importance of secondary aerosol,
(particularly to the eastern area).
Sub-Regions for Control Strategy Formulation
In formulating control policies for an air basin, it is useful to
distinguish sub-areas with different maximal characteristic Hi-Vol
levels. The object of control policy is to reduce each of these
characteristic levels to the air quality standards. In some cases,
different degrees of control may be required for different sub-areas.
In choosing an explicit number of sub-areas to consider, a balance
should be struck between simplicity and realism. The fewer the sub-areas,
the easier it is to formulate, implement, and administer a control
program. The greater the number of sub-areas, the more specific and
efficient is the control program.
For the purpose of control strategy formulation in the Los Angeles
Region, a three area classification is proposed (see Figure 2-5). Table
2-7 lists the sub-areas along with the characteristic maximal AGM'S and
24 hour extrema for the 1972 base year. It should be emphasized that
the characterstic values in Table 2-7 are not the typical values for
2-22
-------
ro
i
ro
co
SANTA BARBARA AND
VEtlTURA COUNTY SUB:AREA
Figure 2-5 Sub-Areas for Control Strategy Formulation
-------
the region but rather the maximal values among all monitoring sites
in the region. These characteristic values are approximate; the numbers
have been rounded to reflect their approximate nature.
TABLE 2-7 CHARACTERISTIC MAXIMAL HI-VOL LEVELS IN
THREE SUBAREAS OF THE LOS ANGELES REGION
(FOR BASE YEAR 1972)
AREA
A.
B.
C,
Ventura and Santa Barbara
Counties
Los Angeles, Orange, San
Bernardino, and Riverside
Counties (except area C
below)
Western San Bernardino
County Hot-Spot
FEDERAL STANDARDS
Primary
Secondary
CHARACTERISTIC
MAXIMAL AGM
80 jjg/m3
1 50 fig/m3
200 >ig/m3
75 }jg/m
60 jug/m3
CHARACTERISTIC
MAXIMAL 24 HR. EXTREMUM
1 80 >jg/m3
470 jug/m3
700 jjg/m3
260 )jg/m3
150 jug/m3
2-24
-------
2.2 EMISSION INVENTORIES AND PROJECTIONS
The development of air pollution control strategies for the improvement
of ambient air quality depends on a detailed knowledge of the quantity and
character of pollutant emissions in the region. This section summarizes
the effort performed in this study to develop an inventory for emissions
of particulates, S09, NO , and reactive hydrocarbons in the Metropolitan
b. /\
Los Angeles Region. Section 2.2.1 describes the development of the 1972
base year emission inventory. Section 2.2.2 outlines the development of
a projected emissions inventory for the future years, 1977 and 1980.
A more detailed discussion of these aspects of the study (emissions
quantification and projection) may be found in Support Document #2, [2],
2.2.1 Development of the 1972 Base Year Inventory
A preliminary search of available emissions data revealed that 1972
would be the most recent year in which reasonably complete emissions infor-
mation could be obtained. Hence 1972 was selected as the base year for the
emissions inventory. Data sources were investigated, study policies and
assumptions were formulated, emission estimation methodologies were
established, and subsequently, the 1972 base year inventory was compiled.
The following sections describe the various elements of the inventory
development.
Data Sources and Study Policies
Previous studies, [23],[24],[25], in which air pollutant emission in
the Los Angeles region were quantified were obtained for review. The
utility of these studies was found to be rather limited in terms of their
applicability to the present study. Emission inventories which have been
previously compiled are generally incomplete in the sense that they do
2-25
-------
not reflect more current and extensive data now available and they do not
provide a sufficiently detailed characterization of the emission sources.
Because of these limitations, TRW developed a separate emission inventory
based on consideration of various emission studies involving the many
specific emission source categories. The following discussion relates
some of the more important studies, data sources, and general rationale
utilized to select the data and policy base, which was subsequently used
to construct the base year emission inventory.
Stationary Sources:
The Los Angeles Air Pollution Control District maintains
a staff of emission analysts for each of the major emission
source categories 'and a source permit file containing
detailed information for each of the large individual emission
sources in the county. No other agency is in as favorable
a position to characterize the air pollution arising from
stationary sources. The air pollution control districts of
Orange, San Bernardino, Ventura, Riverside, and Santa
Barbara are similarly in a favorable position to assess the
emissions from stationary sources within their jurisdiction.
Hence the stationary source inventories developed by the APCD's
were considered the most appropriate data sources except
for special cases in which it was demonstrated that a more
extensive alternative data base was available. The two
most significant special cases in which APCD emission data
were disregarded in favor of other information concerned:
1) emissions of NO from stationary sources in the Los
A
2-26
-------
Angeles Region, (determined in a recent study by KVB
Engineering, Inc. while under contract to the Air
Resources Board), and 2) emissions of particulates, SCL.
and NO from Southern California Edison power plants,
/\
(available from emissions study performed by the Southern
California Edison Company).
Additional data was obtained from the National Emissions
Data System for individual sources generating greater than
100 tons/year of pollutants. These data were used
specifically to characterize spatial emission distri-
butions (discussed, later in this section).
t Motor Vehicle Emissions:
Several sources of information were investigated during
the preparation of the motor vehicle emission source
inventory. Calculations of S09, NO , and reactive
£ /\
hydrocarbon emissions were performed by utilizing published
EPA emission factors [26] in preference to methodology
developed by the Los Angeles APCD. Because of the rela-
tively limited attention addressed to the quantification
of emissions of particulates from motor vehicle exhaust
in previous studies, several recent automotive emission
studies were synthesized to develop particulate emission
factors which were believed to be more representative of
motor vehicle emissions than either the EPA or APCD
published emission factors.
2-27
-------
Aircraft Emissions:
Both the EPA and the Los Angeles APCD have published
separate emission inventories for aircraft operations
at the Los Angeles International Airport. The APCD
figures are based on a recent detailed study, [27], in which
emission factors were derived from field measurements.
These were considered the most acceptable information
source for the present study. Aircraft emissions at
other airports were determined from the estimates
contained in the various APCD emission inventories.
Hydrocarbon Reactivity Factors:
Hydrocarbon emissions were tabulated in terms of
reactive hydrocarbons, determined by employing reactivity
factors established from an EPA analysis of empirical smog
chamber data, [25]. These reactivity coefficients express the
potential of the organic emissions to form photochemical
oxidant, and do not specifically represent the aerosol-
forming potential of organics. However, it
has been found that organics which are non-reactive in
terms of oxidant yield are generally also non-contributory
to aerosol formation. Hence, while the EPA reactivity
scale expresses potential for oxidant formation, it also
provides a limited representation of the aerosol-forming
potential, and as such, is more suitable for use in this
study than a total hydrocarbon scale.
2-28
-------
Suspended and Total Particulates:
In the primary particulate emission inventory developed
in this study, a distinction was incorporated between
suspended particulates and total particulates. Suspen-
ded particulates were assumed to be those actually
measured at sampling stations, whereas the term total
particulates refered to all source emissions of parti-
culate matter, including the larger particles which
settle out on surfaces neighboring the emissions source.
In the emission inventory 10 microns was chosen as the
dividing point between suspended and total particulates.
The size distinction and delineation of the two separate
segments of the particulate inventory were considered
important in the study since ambient air quality is re-
lated to the suspended portion of the particulate inven-
tory, while air pollution control technology for parti-
culate matter is more commonly expressed in relation to
total particulate emissions.
t The Four County Area:
Air monitoring and meteorological data have demonstrated
that the air resources of Santa Barbara and Ventura
counties are relatively remote from the remaining "Four
County Area" of the South Coast Air Basin in a meteo-
rological sense, and that consequently the air pollu-
tion-problems of these two portions of the basin are
separate. In addition, air monitoring data demonstrate
that the National Ambient Air Quality Standards
2-29
-------
for participate concentrations are seldom exceeded in
Santa Barbara and Ventura. These factors would suggest
the sensibility of developing separate air resources
management techniques for the Four County Area and the
northern portion of the air basin, directing the
major effort of the study to develop an air program
plan for the worst case of the basin, the Four County
Area.
The 1972 Baseyear Inventory
Table 2-8' provides the 1972 Four County Area emissions inventory
developed in this study. Stationary sources generate the majority of
primary particulate and S02 emissions, while mobile sources account for
a high percentage of the NO and reactive hydrocarbon emissions. The
/\
relative role of each of the various source categories in overall emissions
totals is shown in Figure 2-6. Stationary fuel combustion and motor
vehicles are the two greatest pollutant emitters, accounting for the majority
of all pollutants emitted in the Four County Area. In 1972, stationary fuel
combustion was the largest single source of SOp emissions, while motor
vehicles were the greatest emitters of primary particulates, NO , and
J\
reactive hydrocarbons. The other most significant emission sources are
petroleum operations, chemical processing, and aircraft activity. The
methodology employed in deriving emission estimates for the individual
source categories is described in the following discussion.
Stationary Emission Sources:
Inventories provided by each of the local air pollution
control districts were used in the compilation of the
2-30
-------
TABLE 2-8. 1972 EMISSION INVENTORY OF PRIMARY PARTICULATES AND GASEOUS
PRECURSORS FOR THE FOUR COUNTY AREA
Source Category
Stationary Sources
Petroleum
Petroleum Refining
Petroleum Marketing
Organic Solvent Operations
Industrial Spray Booths
Surface Coating
Dry Cleaning
Degreasing
Other
Chemical Processing
Chemical Manufacturing
Sulfur Recovery
Other
Metallurgical Operations
Sand Handling
Melting and Pouring
Mineral Processing
Aggregate Operations
Abrasive Blasting
Other
Incineration Operations
Fuel Combustion
Power Plants
Industrial
Domestic
Agricultural
Orchard Heaters
Stationary Source Subtotal
Mobile Sources
Motor Vehicles
Light Duty
Heavy Duty
Diesels
Motorcycles and
Mi seel laneous
Motor Vehicle Tire
Wear
Aircraft
Jet
Piston
Ship and Railroads
Mobile Source Subtotal
Total Inventory
Emissions, tons/day
Primary Parti culates
Total
3.0
...
8.0
...
...
...
10.2
---
...
0.7
11.6
2.8
2.5
6.0
2.2
22.3
12.0
10.6
2.2
93
58.6
1.7
4.1
5.8
31 .1
11.5
3.5
1.5
118
212
Suspended
3.0
7.2
--- ..
...
...
...
9.2
---
...
0.7
11.6
2.5
2.2
5.5
2.0
22.1
12.0
10.6
2.2
90
47.5
1.4
3.3
4.7
15.2
11.4
2.8
1.2
88
178
S02 NOX
60 67.5
---
--.
---
---
95
2.0 0.4
...
13.0 0.5
---
---
1.4
1.6
180 93.5
27.6 115
.3 74.1
1.1
381 353
39.8 747
.6 27
. 8.5 117
59
3.4 12.4
.2 6.2
10.8 24.0
63 993
444 ' 1 345-
Reactive
Hydrocarbons
7.0
67.1
10.0
1.0
10.0
22.0
---
---
---
...
---
---
.3
---
---
---
.4
118
827
31
12
91
9.9
5.8
---
977
1095
2-31
-------
SUSPENDED PARTICULATES
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S^:
-------
stationary source emission inventory of this study. Excep-
tions to this procedure were incorporated for estimation of
power plant emissions and emissions of NO from all
X.
source categories. Power plant emission estimates
were obtained from Southern California Edison for their
power plants. These emission estimates were scaled
upward to include Los Angeles Department of Water and
Power plants by applying the assumption, that emissions
are proportional to electric generating capacity.
Estimates of NO emissions from .the various source
/\
categories were obtained from the inventory provided
by KVB Engineering.
The reactive hydrocarbon emission inventory was adjusted
to reflect the current set of reactivity coefficients
derived by the EPA. The total particulate emission inven-
tory was adjusted to a suspended particulate inventory by
application of suspension factors relating to the various
source categories. The suspension factors were deter-
mined primarily by consultation with Los Angeles APCD
air pollution emission analysts (see Support Document
#2), and are related directly to the degree of parti -
culate pollution control presently applied to a given
particulate emission source.
Mobile Source Emissions:
Emission estimates of particulates from light duty motor
vehicle exhaust were based on empirical results of
2-33
-------
automotive studies by Habibi and Ter Haar, [28] . A
synthesis of findings from these studies yielded a set of
particulate emission factors for new cars and old cars,
and for both suspended particulates and total particu-
lates. These emission factors were utilized in conjunc-
tion with the regional vehicle age distribution to derive
a weighted average emission factor for exhaust particu-
lates. Particulate emissions (suspended and total) for
the Four County Area were then computed from vehicle mile-
age data extracted from the Los Angeles Regional Transporta-
tion Study, [24]. Emissions of gaseous percursors from
light and heavy duty gasoline powered motor vehicles were
calculated using current EPA emission factors and deterio-
ration factors, combined with vehicle population data from
R. L. Polk and Company, and VMT data from the Los Angeles
Transportation Study. The details of the procedure for
these calculations are described in Appendix C of Support
Document #2, [2]. The EPA emission factors were selected for
the emission calculations by direction of the project
officer for the stiidy. It was recognized however, that a
controversy presently exists between the EPA and the
California Air Resources Board concerning emission factors
of gasoline powered motor vehicles. These differences
result in two distinct motor vehicle emission inventories
and lead to substantial differences in estimates of
potential emission reductions via motor vehicle controls.
2-34
-------
Motor vehicle S02 exhaust emissions were estimated
using EPA emission factors, adjusted to reflect the
regional content of sulfur (.067%) in gasoline sold
in Southern California.
Emissions from heavy-duty diesel vehicles were estimated
using EPA emission factors (expressed in pounds of
pollutant per gallon of fuel) and 1970 diesel fuel- con-
sumption data obtained from the National Emissions Data
System. Fuel consumption for 1970 was projected to
1972 by adjusting by the diesel truck registration
growth rate.
Particulate and gaseous precursor emissions from motor-
cycles were calculated using EPA emission factors,
population data from the California Department of Motor
Vehicles, and an assumed annual VMT of 4000 miles per
cycle, [29].
The quantity of aircraft, ship and railroad parti -
culate and gaseous precursor emissions were obtained
from the supplement to the Implementation Plan - South
Coast Air Basin, submitted to the Air Resource Board
by the local APCD's.
Particulates are also emitted to the atmosphere in
substantial amounts due to vehicle tire wear. Cal-
culations for these emissions were based on EPA emission
factors. The suspended portion of matter arising from
tire wear is estimated to be 49% of the total particulate
emissions , [30].
2-35
-------
The reactive hydrocarbon emission inventory for mobile
sources was adjusted to reflect the current set of
reactivity coefficients derived by the EPA, and the
total particulate emission inventory was adjusted to
a suspended matter inventory by application of sus-
pension factors determined for emissions of each of
the individual source categories.
Locational Considerations
A special feature of this study was the presentation of the spatial
distribution of emissions on maps. Typically, emission inventories are
expressed on an aggregated basin-wide basis with no indication of
spatial distribution. The emission maps were produced to provide an aide
in evaluating locational aspects of control strategies.
Figures 2-7 through 2-10 provide the approximate spatial distribution
of emissions of particulates, reactive hydrocarbons, sulfur dioxide, and
nitrogen oxides in the Los Angeles Region for the 1972 base year. These
maps were formulated by locating the most significant emission sources, and
then assuming a simple proportional relationship between the known source
activity level (such as the megawatt capacity of a power plant, or the
barrels/day throughput of a refinery) and the aggregated overall emission
totals of the emission inventory of Table 2-7. The procedure is explained
in more detail in Support Document #2, [2 ] .
Examination of the emission density maps reveals that emission
of reactive hydrocarbons and nitrogen oxides are distributed evenly
throughout the basin, in a pattern which parallels the distribution
of vehicular activity (the primary source of these pollutants). The density
2-36
-------
GO
Figure 2-7. Particulate Emission Density Map.
1 Dot = 2 Tons/Day Total Participate Emissions
-------
OJ
00
Figure 2-8. Sulfur Oxides Emissions Density Map.
1 Dot = 2 Tons/Day SOX Emissions
-------
ro
i
GO
Figure 2-9. Reactive Hydrocarbon Emission Density Map.
1 Dot = 10 Tons/Day of Reactive Hydrocarbon Emissions
-------
ro
i
Figure 2-10. Nitrogen Oxides Emission Density Map.
1 Dot = 11 Tons/Day NOX Emissions
-------
plot of primary participate matter provides a similar distribution, except
for a distinct concentration of participate emissions appearing in the
area of the Los Angeles International Airport. The plot of S02 emissions
shows intense emission densities in the coastal regions, where power uti-
lities and oil refineries emit the bulk of S02 emissions for the Four County
Area.
2.2.2 Development of Emission Projections for 1977 and 1980
Predictions of the quantities of particulate and gaseous precursor
emissions which will be generated in the Los Angeles Region in 1977 and 1980
were formulated for two sets of future conditions. Projections were made
in the first case under the condition that local APCD and federal new car
air pollution control programs are implemented. Emission forecasts were
formulated in the second case under the condition that the EPA-promulgated
air program plan for achieving the oxidant standard is implemented. The
following sections describe the development of these emission projections.
Data Sources and Study Policies
A search of the public domain indicated that limited research has been
directed toward the development of emission forecasts for the Los Angeles
Basin. It was necessary therefore to develop predictions specifically for
this study based on various information sources characterizing the anti-
cipated future activities of each of the source categories. The more
important data sources, and the general rationale used to select the data
and policy base for constructing the projected emission inventories, are
related below.
2-41
-------
t Stationary Sources:
The various independent data sources consulted with
respect to the various different stationary source
categories and the basic assumptions regarding the pro-
jection of the stationary emission inventory are
summarized in Table 2-9. For the majority of source
categories, the projected rate of increase of air
pollution emissions was considered to be equal to the
rate of increase in total employment in the county.
Employment trends and predictions were available from
a study performed by the Wells Fargo Bank, [31]. Projected
emissions from fuel combustion were predictable from
projections of natural gas supplies available from the
Southern California Gas Company. It was determined that
emissions from refining activity of the petroleum industry
could be projected based on environmental impact studies
assessing the nature of changing emissions at oil refineries
expecting to develop new facilities by 1980. Future
emissions of reactive hydrocarbons resulting from petroleum
marketing activities were assumed to be reflected by histor-
ical gasoline marketing trends, (4% per year growth rate),
available from a previous study of the Metropolitan
Los Angeles Region by TRW, [24].
« Motor Vehicle Emissions:
Emissions from motor vehicles have been previously projected
for the purpose of oxidant control strategy development, [24]
2-42
-------
TABLE 2-9. SUMMARY OF ASSUMPTIONS AND DATA SOURCES USED FOR BASELINE EMISSION INVENTORY 'PROJECTIONS
TO 1977 AND 1980
ro
00
Petroleum
(1)
(2)
(3)
Production
Refining
Marketing
Organic Solvent
(1) Surface Coating
Dry Cleaning
Degreasing
Other
(2)
3)
4)
Los Angeles
1
9
3
4
4
4
4
Chemical
(1) Petrochemical
(2) Sulfur Plants
(3) Sulfur ic Acid Plants
(4) Pulp and Paper
(5) Other
4
4
4
4
4
Metallurgical
(1) Ferrous 4
(2) Non Ferrous 4
Mineral
(1) Glass and Frit 4
(2) Asphalt Batching 4
(3) Asphalt Roofing 4
(4) Cement Production 4
(5) Concrete Patching 4
(6) Other 4
Orange
1
2
3
2
2
4
4
2
2
2
2
4
4
4
4
4
4
4
4
4
Riverside San Bernardino Santa Barbara
2
2
3
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
2
2
3
4
4
4
4
2
2
2
2
2
4
4
4
4
4
4
4
4
2
2
2
4
4
4
4
2
2
2
2
2
2
2
4
4
4
4
4
4
Ventura
2
3
4
4
4
4
4
4
4
4
4
2
2
4
4
4
4
4
4
-------
ro
TABLE 2-9. SUMMARY OF ASSUMPTIONS AND DATA SOURCES USED FOR BASELINE EMISSIONS INVENTORY PROJECTIONS
TO 1977 AND 1980 (CONTD)
Los Angeles
Orange
Incineration
(1) Open Burning
(Dumps)
(2) Open Burning
(Backyard)
(3) Incinerators
(4) Other
Combustion of Fuel
(1) Steam and Power
Plants
(2) Other Industrial
(3) Domestic and
Commercial
Agricultural
(1) Debris Burning
(2) Orchard Heaters
(3) Agricultural
Production Pro-
cessing Plants
Riverside San Bernardino Santa Barbara
Ventura
2
2
8
2
6
7
7
2
2
2
2
2
8
2
6
7
7
5
2
2
2
2
8
2
6
7
7
5
5
5
2
2
2
5
6
7
7
2
5
2
2
2
2
2
6
7
7
5
2
2
2
2
2
5
6
7
7
5
5
5
Assumption #1: There will be no change of emission levels from 1972 because no new oil fields or increased
production from existing fields and refineries is expected.
Assumption #2: There were no emissions from these sources in 1972 and none is expected in the future.
Assumption #3: The historical 4% per year growth rate in gasoline sales is expected to hold true in the
future. No attempts have been made to assess the impact of possible fuel shortages on
gasoline sales.
-------
ro
en
TABLE 2-9. SUMMARY OF ASSUMPTIONS AND DATA SOURCES USED FOR BASELINE EMISSIONS INVENTORY PROJECTIONS
TO 1977 AND 1980 (CONTD)
Assumption #4: The rate of increase in emissions is equal to the rate of increase in the total
employment of each county, which is given below:
Los Angeles 1.5% per year
Orange 3.5% per year
Riverside 2.5% per year
San Bernardino 2.3% per year
Santa Barbara 2.3% per year
Ventura 2.9% per year
Source: "Moving Ahead - Wells Fargo Looks at California," Wells Fargo Bank, 1973.
Assumption #5: The emissions from these sources are assumed to remain constant
through 1980.
Assumption #6: Emission projections were assumed to be best represented by Southern California Edison.
Assumption #7: Emission projections were assumed to be reflected best by the 1973 California Gas Report.
Assumption #8: Emissions are assumed to increase at the same rate as population in each county.
Assumption #9: Emission projections reflecting the anticipated expansions at local refineries
(Atlantic Richfield and Standard Oil) were based on emission estimates from
environmental impact statements associated with the proposed Standard Oil expan-
sion project (as conveyed to TRW by the EPA, [33]).
-------
However, these projections were made prior to the
granting of delay to the automobile manufacturers in
meeting the Clean Air Act standards. Moreover,
these projections did not address primary particulates
and the gaseous percursor, SOp- Hence, new projec-
tions were developed for the entire range of motor
vehicle types to incorporate the modified status of
vehicle emission control regulations and to character-
ize the specific pollutants of interest in this study.
The results of recent automotive studies were synthe-
sized in the approach to develop particulate emis-
sion factors representative of future motor vehicles.
Projection of emissions from uncontrolled motor
vehicles (such as exempted automobiles, motorcycles,
dune buggies, farm equipment, and earth moving equip-
ment) has been studied by Automotive Environmental
Systems in a contract effort for the Air Resources
Board, [28]. The study includes predictions of emissions
from uncontrolled motor vehicle sources from 1970 to
1980 for each air quality region in California.
Aircraft Emissions:
In accord with the data sources selected for the base year
aircraft emission inventory, projected aircraft emissions
for the various counties were determined based on
predicted jet emission trends identified by the
2-46
-------
Los Angeles APCD for the Los Angeles International
Airport. Piston aircraft emissions were projected
to the future based on an aviation study performed
by the System Development Corporation, [32].
Projected Emissions Inventory for 1977 and 1980
Table 2-10 provides the baseline emissions inventory summary for 1972,
1977, and 1980, when present emission control programs (APCD control plans-in
combination with the federal new car emission controls) are implemented.
Adding additional emission controls by implementing the EPA-promulgated air
program (which includes vapor recovery systems at gasoline stations,
additional controls on organic solvent usage, a motor vehicle inspection/
maintenance program, and catalytic converter retrofit to light duty motor
vehicles) results in the projected emission inventory shown in Table 2-11.
The overall emissions totals in future years for the two different control
programs are illustrated in Figures 2-11 to 2-14. For either control program,
emissions of primary particulates, S0?, and NO are projected to increase
fc /\
substantially by the years 1977 and 1980. These increased emissions are due
primarily to two factors: growth of the category sources and increasing
utilization of fuel oil (replacing the cleaner-burning natural gas) in
stationary combustion equipment. Due to intensive efforts to meet the
oxidant ambient air standards, reactive hydrocarbon emissions in the Four
County Area will be reduced by more than one-half by the year 1980.
Figures 2-11 to 2-14 show that the control measures of the EPA air program
are most effective in reducing hydrocarbon emissions below the levels ex-
pected under presently scheduled control programs. The EPA program would
reduce reactive organic emissions an additional 15% beyond the emission
2-47
-------
TABLE 2-10. PROJECTED EMISSION INVENTORY FOR THE FOUR COUNTY AREA WHEN THE PRESENT EMISSIONS
CONTROL PROGRAM IS IMPLEMENTED
ro
-Ck
CO
Process Category
Stationary Sources
Petroleum
Organic Solvent
Chemical
Metallurgical
Mineral
Incineration
Fuel Combustion
Agricultural
Mobile Sources
Light Duty Vehicles
Heavy Duty Vehicles
Diesels
Aircraft
Motorcycles, off-road vehicles
Motor Vehicle tire wear
Ships and Railroads
Total Inventory
Suspended Particulates
1972
3.0
7.2
10.2
12.3
10.3
2.0
44.7
2.2
47.5
1.4
3.3
14.2
4.7
15.2
1.2
178
1977
3.0
7.7
10.7
13.4
11.0
2.3
82.6
2.9
45.3
1.6
3.9
25.7
5.6
17.4
1.2
233
1980
3.0
7.8
11.1
14.0
11.5
2.3
80.7
2.9
40.2
1.7
4.1
37.0
6.2
18.6
1.2
240
S02
1972
60.0
---
97.0
13.0
1.4
---
208.0
1.1
39.8
.6
8.5
3.6
_._
__.
10.8
444
1977
60.0
---
10.0
15.0
1.7
...
374.0
1.1
41.2
.8
9.7
6.5
---
___
10.8
530
1980
60.0
...
10.0
15.9
1.8
...
380.0
1.1
39.9
0.9
10.4
9.6
-__
___
10.8
540
NOX
1972
67.5
...
0.4
0.5
---
1.6
283.0
.-.
747
27.0
117
18.6
59.0
__-
24.0
1345
1977 1980
67.5 67.5
___
0.5 0.5
0.6 0.6
_..
1.8 1.8
672.0 629.0
0.3 0.3
586.0 427
24.7 19.3
133.7 143.2
32.2 45.4
70.2 75.5
___
24.0 24.0
1614 1434
RHC
1972
67.1
43. C
_..
---
---
0.3
---
0.4
827
31.0
12.0
15.7
91.0
...
---
1095
1977
71.1
45.9
-
---
...
0.4
...
0.4
460
24.1
13.7
26.7
99.2
---
___
741
1980
71.1
45.9
---
...
...
0.4
---
0.4
276
17.8
14.7
37.1
104
---
...
567
-------
TABLE 2-11. PROJECTED EMISSION INVENTORY
IS IMPLEMENTED
FOR THE FOUR COUNTY AREA WHEN THE EPA AIR PROGRAM
Process Category
Stationary Sources
Petroleum
Organic Solvent
Chemical
Metallurgical
Mineral
Incineration
Fuel Combustion
Agriculture
Mobile Sources
Light Duty Vehicle
Heavy Duty Vehicles
Diesels
Aircraft
Motorcycles, off-road vehicles
Motor Vehicle tire wear
Ships and Railroads
Total Inventory
Suspendec
1972
3.0
7.2
10.2
12.3
10.2
2.0
44.7
2.2
47.5
1.4
3.3
14.2
4.7
15.2
1.2
Particulates
1977 1980
3.0 3.0
7.7 7.8
10.7 11.1
13.4 14.0
11.0 11.5
2.3 2.3
82.6 80.7
2.9 2.9
35.1 33.6
1.6 1.7
3.9 4.1
25.7 37.0
5.6 6.2
17.4 18.6
1.2 1.2
178 223 233
so2
1972
60.0
---
97.0
13.0
1.4
---
208
1.1
39.8
.6
8.5
3.6
---
---
10.8
444
1977
60.0
---
10.0
15.0
1.7
---
374
1.1
35.6
.8
9.7
6.5
---
---
10.8
524
1980
60.0
000
10.0
15.9
1.8
-._
380
1.1
35.7
.9
10.4
9.6
---
---
10.8
535
NOX
1972
67.5
---
0.4
0.5
---
1.6
283
-._
747
27.0
117
18.6
59.0
---
24.0
1345
1977
67.5
._-
.5
.6
---
1.8
672
0.3
586
24.7
134
32.2
70.2
...
24.0
1614
1980
67.5
---
0.5
0.6
---
1.8
629
0.3
427
19.3
143
45.4
75.5
---
24.0
1434
RHC
1972
67.1
43.0
-_.
---
---
0.3
---
0.4
827
31.0
12.0
15.7
91.0
---
-'--
1095
1977
17.3
30.4
---
---
---
0.4
._.
0.4
335
24.1
13.7
26.7
99.2
-_.
...
547
1980
18.2
30.0
---
---
---
0.4
-
0.4
188
17.8
14.7
37.1
104
---
...
410
-------
ro
in
o
250 T
to
c
o
-p
200..
150T-
SUSPENDED PARTICULATES
Present Controls
EPA Controls
SO,
1972
Figure 2-11.
1977
Projection of Particulate
Emissions in Four County Area
1600"
>>
31500-
c
+11400-
1300-
NO /-" \
/ \
/ \
/ ^
/ti rt v
A
/ Present'
7
Xi i i i i i iii
1972
Figure 2-12.
1977 1980
Projection of NOX Emissions
in Four County Area
600 T
500
"° Jinn 4-
c
o
400
300
Present Controls
Controls
_i i
19
372 1977 1980
Figure 2-13. Projection of S02 Emissions in
Four County Area
1200
£1000 +
8004
600--
400-
Present
Controls
EPA
Controls
572 1377 1!
Figure 2-14. Projection of Reactive Hydro-
carbon Emissions in Four County
Area
-------
control attainable by the existing scheduled air programs. However, as
the EPA plan does not address control of particulates, S09, and NO
£ /\
directly, it provides very minimal additional control of these type
of pollutants. In fact, the apparent slight benefit indicated for parti-
culate control in Figure 2-11 from implementation of the EPA plan actually
involves a serious trade-off pollution problem. This problem concerns the
changing character of motor vehicle particulate pollution (increased genera-
i
tion of sulfates) when catalytic converter controls are utilized in auto-
motive exhaust systems as required by the EPA plan.
Figure 2-15 illustrates the dominant role of four source categories
(fuel combustion, petroleum, motor vehicles, and aircraft) in the overall
projected emissions inventory of the Four County Area when the EPA air
program is implemented. By 1980, the four categories are expected to
account for 79% of all the particulate emissions in the Four County Area,
93% of the S0?, 98% of the NO. and 92% of the reactive hydrocarbons.
C* /\
Stationary fuel combustion is expected to become the largest source of
particulates, S0?, and NO by 1980, due to increasing fuel oil utilization
£. /\
schedules for combustion equipment in future years, coupled with the effect
of increasing controls programmed to reduce motor vehicle emissions sub-
stantially by 1980. Motor vehicles will continue to be the most significant
source of reactive hydrocarbon emissions, accounting for approximately 88%
of the overall inventory. Without significant controls expected until 1979,
aircraft emissions are expected to increase markedly over the next decade,
and although the overall quantity of pollution arising from aircraft
activity is a small portion of the total emissions inventory, it is emitted
in a limited area and therefore constitutes a significant local source of
pollution.
2-51
-------
o
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,ion Vehicles roleum Aircraft Other c. Combustion Vehicles roleum Aircraft Other
° 100-r
X
o
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4->
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QJ
CM
r>>
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ps.
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co
cn
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Combustion Vehicles roleum Aircraft Other
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cn
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r^ rv. o
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Fuel Motor
Combustion Vehicles
Pet-
roleum Aircraft Other
Figure 2-15.
The Projected Role of the Various Major Source Categories in Emissions of
Particulates and Gaseous Precursors in the Four County. Area under the EPA
Air Program
-------
The methodology employed to develop the projected emission estimates
(Tables 2-10 and 2-11)for each of the source categories, for both the
EPA air program and the present air pollution control program, is de-
scribed in the following discussion.
Estimation of Emission Projections under Present Controls:
Petroleum Industry Emissions. Except for Los Angeles
County, all counties reporting emissions due to refining
process operations are expected to have the same quantity
of emissions through 1980. In Los Angeles County, emis-
sions will change at Standard Oil and Atlantic Richfield
due to construction of new facilities scheduled for com-
pletion before 1977. The effect of these new facilities
on projected refinery emissions have been assessed and
reported in the related environmental impact statements
submitted prerequisite to the construction permit, [33].
Because of improvements in emissions control which will
accompany the new construction, emissions of reactive
hydrocarbon emissions will decrease by .5 tons. All other
pollutant emissions will remain unchanged, except for those
arising from new refinery combustion equipment, which is
classified as a stationary combustion source in the emis-
sion inventory of this study.
Reactive hydrocarbon emissions from marketing operations
were projected by assuming a continuation of the historical
4% per year gasoline sales increase, and by accounting for
a 90% reduction in these emissions starting in 1975 due
2-53
-------
to initiation of the Los Angeles APCD vapor recovery rule
(Rule #65) targeted for gasoline service station storage
tanks.
i
Organic Solvent Operations. Chemical Processing, Metallurgical.
and Mineral Processing. The yearly growth rate of emis-
sions was calculated by assuming it equal to the projected
yearly increase in total employment for the county (see
Table 2-9).. An exception to this procedure was incor-
porated in the estimation of future emissions of SC^ from
sulfur recovery plants. These emissions were assumed
constant at 10 tons/day of SOp over the next several years
due to: (1) enforcement of Rule 53 limiting SOg stack con-
centrations, and (2) relatively constant activity expected
from the recovery plant feed sources (petroleum refinery
offstream gases) until 1980.
Agriculture and Incineration. Emission rates from agri-
culture related industries were assumed to be unchanged
through 1980. Emissions due to incineration operations
were assumed to increase at the same rate as the popula-
tion in each county. Population projections were avail-
able from the State Population Research Unit, [34].
Stationary Fuel Combustion. Estimations for projected
emissions arising from power plant fuel combustion were
based on projections of emissions developed by the
Southern California Edison Company. Edison has based
these estimates on expected customer demands, availability
2-54
-------
of natural gas and low sulfur fuel oil, and purchased
power from Edison plants outside the air basin. Emis-
sions from Los Angeles Department of Water and Power
plants were assumed to be related to their power genera-
ting capacity according to the same proportion indicated
by the Edison Company projected emissions and power
generation figures. Because of the Department of Water
and Power's proposed policy of obtaining future addi-
tional power demands from sources outside the air basin, [35]
emissions from these plants were assumed to remain con-
stant from 1972 through 1980.
Emissions from domestic and commercial fuel combustion
equipment result from the burning of natural gas supplied
by the Southern California Gas Company and the City of
Long Beach. Projected gas deliveries have been estimated
by each of these gas companies, [36]. Using the gas
M
delivery projections and EPA emission factors, [26].
the average daily emissions from domestic and commer-
cial fuel combustion were calculated.
Emissions from industrial fuel combustion equipment are
generated when burning either natural gas or alternate
fuels (primarily fuel oil). The "interruptible" natural
gas consumption of industrial combustion units has been
projected by gas suppliers, [36], for the next several years.
These projections, coupled with emission factors for
combustion of natural gas, permit the calculation of
2-55
-------
the portion of industrial fuel combustion emissions
which arise from the burning of natural gas. The
curtailment (the difference between supply and demand)
of natural gas is made up by the burning of alternate
fuels. Emissions generated by the burning of alternate
fuels were projected to future years by scaling up the
corresponding portion of the 1972 baseyear emissions
with the natural gas curtailment projections (see Support
Document #2, [ 2], for detailed explanation). Because the pet-
roleum refineries manufacture their own supply of com-
bustion fuels from offstream process gases, emission
estimates for this source were calculated separately
and added to the fuel combustion emissions calculated
above. The level of projected emissions from fuel
combustion at the refineries were assumed to remain
constant from 1972 to 1980, except for additional
emissions expected to arise from operation of new
refinery facilities scheduled for completion before
1977. The magnitude of the projected emissions from
fuel combustion at the new refinery facilities was
extracted from the environmental impact statements
associated with the new refinery projects.
Aircraft Emissions. Jet aircraft emissions were assumed
to originate entirely from air carrier airports, while
general aviation airports were assumed to be constituted
2-56
-------
entirely of piston aircraft activities. Jet aircraft emis-
sions were assumed to be increased at a rate of 14% per year,
the historical growth rate of passenger volume from 1960-
1970, [32]. Emissions from piston engine aircraft were esti-
mated to increase at a rate equal to the projected growth
rate of piston aircraft based at the general aviation air-
ports, [32]. The effect of federal aircraft standards, sch-
eduled to become effective in 1979 for new turbine and pis-
ton engines,was considered to be insignificant in 1980.
Motor Vehicles. Light and heavy duty motor vehicle emis-
sions of hydrocarbons and NO were projected using the
/\
standard procedure outlined in Appendix C of Support
Document #2, [2]. Basically, emissions are estimated by
determining the annual mileage by model distribution of
the region's vehicle population, the overall anticipated
mileage traveled by vehicles in the region, and then
applying appropriate emission factors which are attri-
butable to the various vehicle age classifications. The
emission factors reflect the present control program and
the Air Resources Board retrofit program requiring nitro-
gen oxide control devices on all 1966-1970 vehicles.
Emissions of S02 and particulates were calculated on the
basis of emission factors obtained from automotive ex-
haust studies concerning vehicles equipped with catalytic
converters (see Appendix E of Support Document #2, [2 ]),[37].
These emission factors were applied to the segment of
the motor vehicle population expected to be equipped
with the converter by the year 1977 or 1980 (see Appendix
D of Support Document #2, [2]). The remainder of the vehicle
2-57
-------
population was assumed to emit particulates and S02 at
the rate assumed for the baseyear calculation.
Diesel emissions were projected by assuming them equal
to the growth rate of VMT as projected by the Los Angeles
Transportation Study for the Los Angeles area.
Emissions from miscellaneous uncontrolled vehicles were
projected on the basis of the statewide projection to
1980 made by Automotive Environmental Systems* [29]. The
projection to 1977 was calculated by a linear inter-
polation between 1972 and 1980 figures.
Estimation of Emissions Projections under EPA - Promul-
gated Controls:
Stationary Sources. By 1977 the EPA federal air program
will require the installation of vapor recovery systems
at gasoline stations and additional emission controls for
organic solvent operations, [38]. The projected stationary
source emission inventory after implementation of these
controls is calculated by considering the emission reduc-
tions attributable to each of the control measures: an
81% reduction of reactive hydrocarbon emissions at gasoline
stations, and a 33.6% reduction of emission from organic
solvent users , [39].
Motor Vehicles. Under the promulgated EPA air program,
inspection/maintenance and catalytic converter retrofits
are required for a major portion of the light-duty
vehicle population (VMT reduction measures specified under
the EPA plan were not included in this study assessment due
to the current uncertainty with regard to their effectiveness
and socio-economic acceptability). Projections of emissions
with these control measures in effect were calculated by
2-58
-------
attributing a 15% reduction in hydrocarbon emissions from
motor vehicles affected by the inspection/maintenance pro-
gram, and a 50% reduction in hydrocarbon emissions from motor
vehicles retrofitted with the catalytic converters. Pro-
jection of emissions of particulates and S02 from light
duty motor vehicles retrofitted with the catalytic converter
were calculated utilizing emission factors extracted from
recent relevant automotive studies, [37]. The methodology of
the calculation is the same as that used in deriving emis-
sions of particulates and S02 from the motor vehicle popu-
lation characterized under the "present control plan," which
involves a lesser percentage of vehicles equipped with the
converter. A detailed explanation of the projection esti-
mates is contained in Appendix C, D, and E of Support Docu-
ment #2, [ 2].
2.3 A METHODOLOGY FOR RELATING EMISSION LEVELS TO AMBIENT PARTICULATE AIR
QUALITY
In order to formulate a systematic air quality implementation plan, a
methodology is needed to translate emission level changes into air quality
changes. Specific to this project, a model is required to determine how
suspended particulate air quality will depend on emissions of primary
particulates, S02, NOX, and RHC in the Los Angeles Region. Such a model
can be used to transform emission projections into air quality forecasts
and to predict the atmospheric impact of various control strategies.
Support Document #3 develops the model to be used in this study, [3].
The present section summarizes the major results of that development
process. The air quality - emission level model depends on two basic
analyses. First, the origins of suspended particulates are identified at
2-59
-------
several locations in the Los Angeles Region, (See Section 2.3.1). Second,
the dependence of the controllable (non-background) origin categories on
contaminant emissions levels is determined, (Section 2.3.2.). As shown in
Section 2.3.3., the air quality-emissions level model is completed by a
synthesis of these two results.
2.3.1 Characterization of Aerosol Origins in the Metropolitan Los
Angeles Region
The development of a systematic relationship between pollutant emissions
and measured suspended particulate levels required identification of the
origins of suspended particulate matter. This study employed the fol-
lowing classification scheme to characterize aerosol origins:
AEROSOL ORIGIN CLASSIFICATION SCHEME
I. Background Contributions
A. Primary
Sea Salt
Soil Dust
Primary Anthropogenic
Sources Exterior to
the Los Angeles
Region
B. Secondary
Sulfate
Nitrate
Secondary
Organics
II. Non-Background Contributions
(Anthropogenic Sources within
the Los Angeles Region)
A. Primary
B. Secondary
Total Primary
Sulfate
Nitrate
Ammonium _
Secondary
Organics
2-60
-------
It was found that there were 12 locations in the Metropolitan Los
Angeles Region with sufficient data on aerosol chemical composition to
support the origin analysis. These locations are illustrated in Figure 2-16.
As noted above, the origin characterization was carried out only for annual
mean particulate levels, not for 24 hour maximal levels.
Estimates of Background Contributions
For the purposes of this study, the background aerosol is defined as
that part of the total aerosol which is not subject to emission regulations
i l '
in the Los Angeles Region. Thus, the non-background aerosol is that
portion subject to direct emission control. The three raain sources of
; . !
i
background aerosol are natural sources, dust resulting from activities
such as agriculture or traffic, and man-made emissions exterior to the
Los Angeles Region. Water aerosol was not included in the background
classification because there are indications that, unlike the ambient
aerosol, equilibriated Hi-Vol samples contain negligible amounts of water,
(see Support Document #1 for a discussion).
Background particulate levels may undergo significant spatial variations
in the Los Angeles Region. In this study, three general areas were dis-
tinguished for the background aerosol analysis: the coastal area, the
central-valley area, and the eastern-inland area, (see Figure 2-16). In
the final origin characterization, adjustments were made for individual
monitoring sites within these general areas, (see later, Table 2-17).
Two methods were used to estimate background aerosol levels. METHOD
I derived estimates of overall background levels by reviewing total Hi-Vol
measurements at several (non-urban) marine and desert locations in the
Southern California area. METHOD II determined values for each specific
category of background aerosol. Sulfate, nitrate, secondary organics,
and man-made primary sources exterior to the Los Angeles Region were
2-61
-------
ro
a\
ro
Figure 2-16 Locations for the Aerosol Origin Characterization
-------
estimated from data at the non-urban locations. The sea salt and soil
dust contributions were found by applying a chemical element tracer
technique to sodium and aluminum measurements taken within the Los
Angeles Region. In METHOD II, the total background levels were found by
adding the contributions from each sub-category. Support Document #3
to this study gives a detailed description of each of the methods.
Table 2-12 compares the background aerosol estimates obtained by the
two methods. Although the variance in the estimates is large, the agree-
ment of overall levels and of trends from coast to inland is extremely
good.
In summary, total background levels in the Los Angeles Region appear
3 3
to vary from around 30-40 ug/m in the coastal area, to around 35-45 ug/m
in the central-valley area, to around 45-55 ug/m in the eastern-inland
area. The approximate origin breakdown for the background aerosol that
was indicated by the analysis is as given in Table 2-13.
TABLE 2-12
ESTIMATES OF AVERAGE TOTAL BACKGROUND LEVELS
(ARITHMETIC MEANS)
COASTAL AREA
CENTRAL-VALLEY AREA
EASTERN- INLAND AREA
METHOD I
: ANALYSIS OF TOTAL NON-
: URBAN LEVELS
: 30-40 jug/m
: 35-50 ajug/m3
: 45^60 ug/m3
METHOD II
BY ADDITION OF ESTIMATES
FOR EACH CATEGORY IN THE
CLASSIFICATION SCHEME
24-46 jjg/m3
27-49 jjg/m3
: 35-57 jjg/m3
a. Interpolation of the Coastal and Eastern Inland Results.
2-63
-------
TABLE 2-. 13
BACKGROUND AEROSOL CLASSIFICATION SCHEME
FOR THE LOS ANGELES REGION
(ARITHMETIC MEANS)
SUB- AREA
COASTAL
CENTRAL-VALLEY
EASTERN- INLAND
APPROXIMATE
TOTAL BACK-
GROUND LEVEL
~35 jjg/m
-40 jjg/m
~50 yg/m
BACKGROUND CLASSIFICATION SCHEME (pg/m3)
SEA
SALT
8
6
4
PR
SOIL
DUST
16
23
35
:MARY
MAN-MADE SOURCES
EXTERIOR TO L.A.
REGION
3
3
3
SECO
so,-
4
4
4
WARY
NO,"
1
1
1
SECONDARY
ORGAN I CS
3
3
3
Hi-Vol Composition Data
In order to determine non-background contributions, data were required
on Hi-Vol chemical composition within the Los Angeles Region. Specifically,
measurements were needed for lead (Pb), sulfate (SOT), nitrate (NOZ),
ammonimum (NH^), and benzene solubles (BSOL). The compositional data base
was reviewed in Support Document #3, and it was found that sufficient data
existed to characterize particulate composition at 12 locations in the Los
Angeles Region. These locations are illustrated in Figure 2-16.
In determining annual average aerosol composition, reliance was placed
on data from three long term monitoring programs: the National Air
Surveillance Network (NASN), The Los Angeles APCD Network, and the San
Bernardino County APCD Network. Some compositional measurements were also
available fron the following monitoring projects:
Orance County APCD Monitoring Program
t California Air Resources Board Monitoring System, [40]
2-64
-------
University of Southern California Study, (Gordon & Bryan [41])
State Air Pollution Research Center Study, (Lundgren, [42])
Air Resources Board/Rockwell International Aerosol Characterization
Study, (ACHEX), (Hidy, [43])
However, the last three of these projects were just of temporary nature,
and the first two supplied compositional data only for lead. Thus, the
latter five projects were used only in a supplementary fashion.
At each location, the average composition measurements from the
various monitoring networks were compared and analyzed. From this analysis,
a percentage contribution from each constituent was determined for each
location. These percentages were then applied to the 1972 expected annual
average Hi-Vol levels, (as determined in Support Document #1), to yield a
compositional breakdown characteristic of the 1972 base year. The results
are given in Table 2-14. The interested reader is referred to Support
Document #3 for the details of the analysis.
A First Iteration for the Aerosol Origin Characterization
As a first iteration, rather simplistic calculations were applied to
the compositional data in order to estimate contributions from the non-
background aerosol categories. Table 2-15 briefly describes these calculations,
A thorough discussion is given in Support Document #3.
As shown in Table 2-16, the calculated non-background contributions
were added to the background estimates to yield "accounted for" values of
average Hi-Vol levels. The results of this first iteration were then com-
pared to the actual average Hi-Vol levels at each location. For all but
three locations, the relative differences between "accounted for" and actual
particulate levels were less than 8%. This agreement was remarkable con-
sidering the simplicity of many of the assumptions inherent in the first
2-65
-------
I"!
TABLE 2-14 HI-VOL PARTICULATE COMPOSITION:
CHARACTERIZATION FOR THE 1972 BASE YEAR
Location
Total Suspended Participates
wr/m
AGM AAH
Cc
1 . Lennox
2. West LA
3. Long Beach
135 145
85 90
95 105
Cen
4. Downtown
LA
5. Pasadena
6. Anaheim
7. Reseda
130 140
110 120
95 105
130 140
Eas
8. Azusa
9. Ontario
10. San
Bernardino
11. Riverside
150 160
110 120
115 125
140 150
Pb
astal Area S
6.7
(4.6%)
3.0
(3.3*)
2.3
(2.2%)
so;
N03
NH+
Benzene Solubles
tes
13.2
(9.1%)
9.3
(10.3%)
11.2
(10.7%)
7.4
(5.1%)
6.8
(7.6%)
5.6
(5.3%)
N/A
N/A
1.5
(1.4%)
N/A
N/A
10.2
(9.72)
ral Vallev Sites
4.1
(2.9%)
3.6
(3.0%)
2.8
(2.7%)
4.3
(3.1%)
ern Inland A
3.0
(1.9%)
1.9
(1.6%)
2.0
(1.6%)
1.8
(1.2%)
14.3
(10.2%)
12.7
(10.5%)
8.7
(8.3%)
12.9
(9.2%)
11.6
(8.3?,)
11.4
(9.5%)
6.5
(6.2%)
8.4
(6.0%)
1.4
(1.0%)
1.2
(1.0%)
0.8
(10.8%)
1.4
(1.0%)
14.0
(10.0%)
13.8
(11.5%)
16.0
(11.4%)
rea Sites
15.2
(9.5%)
10.2
(9.5%)
12.6
(10.1%)
11.7
(7.8%)
17.7
(11.1%)
10.8
(9.0%)
13.1
(10.5%)
15.1
(10.1%)
1.0
(0.8%)
1.0
(.8%)
1.5
(1.0%)
9.4
(7.8%)
11.3
(9.0%)
11.0
(7.3*)
Western San. Bernardino Countv Hot Soot
12. Chino
200 220
2.2
(1.0%)
22.0
(10.0%)
18.0
(9.0%)
1 2.1
(5.5%)
2-66
-------
TABLE 2-15 FIRST ITERATION CALCULATION
METHODS FOR NON-BACKGROUND ORIGIN CATEGORIES
Origin Category
Calculation Method
i
(^Ion-Background Primary Particulates
Lead (Pb) was used as a tracer for
primary particulate contributions.
The total non-background primary
contribution at each site was
estimated by factoring the Pb con-
centration at that site by the
ratio of total regional suspended
particulate emissions to total susp.
regional Pb emissions. This factor
was 12.8, (See Support Document #3).
Non-Background Sulfate Contribution
Non-background sulfate was simply
taken as the total sulfate measured
at each site minus the estimated
3
background level of 4 ug/m .
Non-Background Nitrate Contribution
Non-background nitrate was taken
as the total nitrate measured at
each site minus the estimated back-
3
ground level of 1 ug/m .
JNon-Background Ammonium
Non-background ammonium was taken
as total ammonium minus the esti-
mated background level of .3 ug/m"
Non-Background Secondary Organics
A method using benzene soluble data
along with estimates for the sol-
ubility of both primary and second-
ary organics did not yield, sensible
results. Thus, as a first approx-
imation, an educated conjecture was
made that non-background secondary
organic levels were 10, 20, and 30
in the coastal, central -valley,
and eastern-inland areas respectively.
2-67
-------
TABLE 2-16 AEROSOL ORIGIN CHARACTERIZATION FIRST ITERATION
(ANNUAL ARITHMETIC MEAN '~3'
LOCATION
APPROXIMATE
BACKGROUND AEROSOL
Natural .Contribution, Suspended
Dust, and Man-made Sources
Exterior to the L.A. Region
NON-BACKGRC
(Anthropogenic
dust and sourc
Los Angeles R.£
PRIMARY SO^
UND C(
, exc
es ex
gion)
NO'
DNTRIB
uding
terior
mj
JTIONS
suspended
to the
SECONDARY
ORGAN I CS
ACCOUNTED
FOR
ANNUAL
MEAN
TOTAL 1972
ANNUAL
MEAN
RELATIVE
DIFFERENCE
COASTAL AREA
1 . Lennox
2. West Los Angeles
3. Long Beach
35
35
35
86
38
29
4. Downtown Los Angeles
5. Pasadena
6. Anaheim
7. Reseda
40
40
40
40
52
46
36
55
9
5
7
6
6
5
i
i
i
10
10
10
147
95
87
CENTRAL- VALLEY AREA
10
9
5
9
11
10
6
7
i
i
i
i
20
20
20
20
134
126
108
132
145
90
105
140
120
105
140
+1*
+62!
-17*
-4%
+5%
+3%
-6%
EASTERN -INLAND AREA
8. Azusa
9. Ontario
10. San Bernardino
11 . Riverside
50
50
50
50
38
24
26
23
11
6
9
8
17
10
12
14
i
i
i
i
30
30
30
30
147
121
128
126
160
120
125
150
WESTERN SAN BERNARDINO COUNTY HOT-SPOT
12. Chino 1 50 1 28
18
17
i
30 1 144
220
-8%
+1*
+2*
-17%
-35%
ro
en
CO
-------
iteration calculations. For the locations with larger relative differences,
such as Chino, Long Beach, or Riverside, there were apparent reasons why
some of the simplistic assumptions were not appropriate. These reasons
are discussed in Support Document #3.
Completion of the Aerosol Origin Characerization
In order to formulate a systematic model for the relationship between
pollutant emissions and ambient particulate levels, the total particulate
level at each location should be fully accounted for by the origin
classification scheme. Thus, as a second and final characterization,
the origin contributions in the first iteration were adjusted so that
the total particulate levels at each site were fully accounted for. The
adjustments were made in the most uncertain origin classes: the back-
ground, non-background primary, and non-background secondary organic
categories. The other categories represented direct measurements and were
not adjusted. The rationale behind the adjustments is discussed in
Support Document #3. Large changes were made with distinct reasons, but
some small changes were rather arbritary. The only locations that re-
quired large alterations were Long Beach, Riverside, and Chino.
Table 2-17 presents the complete origin characterization for the
twelve locations in the Metropolitan Los Angeles Region. Although an at-
temp was made to derive the best origin characterization that is possible
with existing data, there is still considerable uncertainty in many of the
values given in Table 2-17. It is difficult to perform a quantitative
error analysis of the results; however, a subjective indication of the
error level is useful in interpreting the results. The most uncertain
category is non-background secondary organics; the error may be as high
as 20 to 40%. The other categories, (total background, non-background primary,
2-69
-------
TABLE 2-17 ORIGIN CHARACTERIZATION FOR ANNUAL MEAN HI-VOL PARTICULATE LEVELS
LOCATION v
Sea
Salt
Suspended
Dust
BACKGROUND CONTR
PRIMARY
Primary Man-made ,'
Sources Exterior to
the L;A. Region
IBUTIONS |
SECONDARY V
so4=
COASTAL
1 . Lennox
2. West Los Angeles
3. Long Beach
8
8
8
16
14
16
3 '
3
3
4
4 ;
4
N°1J
i
Secondary;
Organics'
t
TOTAU
BACK-"'
GROUND*
. NON-BACKGROUND CONTRIBUTIONS.
(Anthropogenic Sources within LA Region)
PRIMARY
SECONDARY
S°4=
N0~
NHj
Secondary
Organics
TflTAl
AAM
AREA LOCATIONS
i ;
1 :
1
3 '
3
3
35^
33 I
35 i
84
36
47
9 '
5,
7
. 6 '
6 '
5
1
1
1
10
9
10
145
90
105
CENTRAL-VALLEY AREA LOCATIONS
4. Downtown Los Angeles
5. Pasadena
6. Anaheim
7. Reseda
6
6
6
6
27
21
23
26
3
3
3
3
4
4
4
4
1 .
1
1
1
3
3
3
3
44 ;
38 .'
40
43
54
42
36
58
10
9
5
9
IT
10
6
7
1
1
1
1
20
20
17
22
140
120
105
140
EASTERN- INLAND AREA LOCATIONS
8. Azusa
9. Ontario
10. San Bernardino
11 . Riverside
4
4
4
4
38
34
33
45
3
3
3
3
4
4
4
4
1
1
1
1
3
3
3
3
53
49
48
60
41
24
26
30
11
6
9
8
17
10
12
14
1
1
1
1
37
30
29
37
160
120
125
150
r\i
o
WESTERN SAN BERNARDINO COUNTY HOT SPOT
|12. Chino"
45
I 1 I
I 60
89
35
220
-------
sulfate, nitrate, and ammonium), are better documented. The error in these
categories should be on the order of 10 to 20%.
Figures 2-17 through 2-20 presents the spatial distribution of the
most significant origin categories. It can be seen that background aero-
sol and non-background nitrate and secondary organics increase with dis-
tance inland. Non-background sulfate shows no consistent spatial trend.
The non-background primary contribution generally decreases with distance
inland. Support Document #3 shows that these trends can be explained
by the source distribution and meteorology of the Los Angeles Region.
2.3.2 The Dependence of Suspended Particulate Levels on Contaminant
Emissions
In the previous section, the portion of the Los Angeles aerosol that
is subject to direct emission control in the Los Angeles Region was class-
ified as non-background. Non-background particulates were subdivided ac-
cording to the following origin categories:
Non-background primary particulates
Non-background secondary particulates
Sulfates
Nitrates
Ammonium
Secondary Organics
Having identified the contributions from these controllable origin
categories, the final step in determining the relationship between emissions
and air quality is to find the dependence of each origin category on emis-
sion levels. In Support Document #3, the existing theoretical and empirical
2-71
-------
ro
i
ro
Figure 2-17 Estimated Non-Background Primary Particulate Levels in the Los Angeles Region
-------
ro
>g
CO
Figure 2-18 Total Sulfate Levels in the Los Angeles Region
-------
Figure 2-19 Total Nitrate Levels in the Los Angeles Region
-------
ro
i
in
Figure 2-20 Estimated Non-Background Secondary Organic Levels in the Los Angeles Region
-------
evidence pertaining to this dependence was reviewed for each origin
category. The results of this review will be summarized below. In genr
eral , it was found that a great deal of uncertainty surrounds the depen-
dence of suspended particulates on emission levels, particularly with
regard to secondary aerosol levels and gaseous precusor emissions. In
the end, the linear rollback formula was chosen for primary particulates,
and a similar linear form was assumed for each of the sulfate/SOp, nitrate/
NOx, and organic/RHC relationships.
Air Quality Relationship for Non-background Primary Particulates
The simple "linear rollback" technique was chosen to provide the
air-quality/emission-level relationship for primary particulates. That
is, non-background primary parti cul ate levels at each location were taken
as directly proportional to total primary suspended particulate emissions
from man-made sources in the region.* Expressed mathematically,
NBPSP^E) = E
'
where
NBPSP. = non-background primary suspended particulate level at
location "i",
E = total primary suspended particulate emissions from anthro-
pogenic sources in the region,
and the subscript "o" refers to base year values.
The applicability of the linear rollback formula to inert primary
contaminants is supported by the linearity of the equation of advective
*As noted later, a modified form of this relationship was chosen for
application at the Chino location which is strongly influenced by
local sources.
2-76
-------
diffusion with one main proviso. The proviso is that the space and time
distribution of emissions does not change when the total emission level
goes from E to E. As discussed in Support Document #3, the assumption
of fixed emission spatial pattern should be fairly well met by the con-
trol strategies to be proposed in this study. The main factor changing
primary particulate emissions will be large reductions from the control
of all significant source categories. This should approximate a homo-
geneous change fairly well. The error in the linear rollback assumption
for primary particulates should be one relatively small compared to other
sources of uncertainty in this study.
Sulfate Air Quality Relationship
The relationship between sulfur dioxide emissions and ambient sul-
fate levels has been the subject of considerable research, much of which
is still in progress. Support Document #3 reviewed the current state
of knowledge. It was found that the oxidation of SOp to form sulfate is
a very complex process and that considerable uncertainty still exists
concerning the SC^/SO^ relationship.
In Support Document #3, the form of the SOp/SOT relationship was
first analyzed by considering known aspects of the chemical transformation
processess. A review of the literature and of current research revealed
that several possible avenues have been identified which can oxidize
atmospheric SCL to yield sulfate aerosol. The three main avenues which
appear to be significant are 1) photochemically induced oxidation of
S02 to SO., in the gas phase with subsequent reactions yielding sulfuric
acid and sulfates, 2) absorption of S02 in aqueous droplets with sub-
sequent catalytic oxidation, and 3) adsorption of SCL on solid particules
with subsequent reaction with adsorbed oxygen. These chemical trans-
2-77
-------
formation mechanisms and the atmospheric factors which affect the reac-
tion rates were described in Support Document #3.
Theoretical analyses indicated that, at low SOp levels, the sulfate
yield would be directly proportional to SOp input for all three mechanisms,
For higher SOp levels, one would expect that the sulfate yield would be-
come less than proportional to SOp input. This expected dependence is
illustrated for a hypothetical experiment and for a hypothetical air
basin in Figure 2-21. Unfortunately, the specific SO* level at which
nonlinear effects become important has not been established from analyses
of the chemical reaction processes.
A second approach used 1n Support Document #3 to investigate the
SCL/S(n relationship involved the empirical analysis of actual atmospheric
data. One empirical method that was tried relied on historical data
for measured ambient sulfates and for estimated SOp emissions, (see Figure
2-22). However, it was found that this method could not yield a systematic
SOp/SO^ relationship from existing data due to the limited range of recent
historical SOp emission levels and due to the meteorological fluctuations
inherent in yearly SOT levels.
A second empirical method involved ambient measurements for both S0?
and SOT. The most comprehensive study of this type was performed by
Altshuller on nationwide NASN data, [45], (see Figure 2-23). In Support
Document #3, this method was also applied to data for the Los Angeles
Region, (see Figure 2-24). In the Los Angeles application, the data were
distinguished as to distance inland in order to decrease the variance
from different SOp residence times. The Altshuller results and the Los
Angeles data appeared to indicate an initial linear increase of SOT with
SOp, followed by a leveling off of SOT at higher SOp levels.
2-78
-------
FIGURE 2-21 a Hypothetical Experiment
-a
c
fO
to
O)
01
u
O)
-o
r-
10
at
s-
s_
o
s-
fO
Q.
S-
ai
Non-Hnear Effects
Linear Sub-region
S02 INPUT
FIGURE 2-215 Hypothetical Air Basin
UJ LU
_
Q 3
UJ LU O
o: i s-
ra <: o>
GO u. .*:
«X _i o
LU Z3 (O
s: oo as
Non-Linear Effects
Linear Sub-region
S02 EMISSIONS
Figure 2-21 Schematic Illustration of the Dependence of
Sulfate Levels on S02 Input
2-79
-------
en
«=c
LU
1C
ID
1 fi-
ll!
1(
d 2
i
70
DO 3
169
30 4
62
* !
63
64
DO 5
A'
57,5
.
»67 GO
,, .
00 6i
f
-------
ro
oo
30
20
<
o:
UJ
o
o
o
10
o o
CD
I
I
I
I
20 40 60 80 100 120 140
SULFUR DIOXIDE CONCENTRATION,
160
3
180
Figure 2-23 Sulfur Dioxide/Sulfate Relationship for 18 U. S. Cities
I
200 220
REFERENCE: Altshuller 145].
-------
Estimated Background Sulfate
60
Yearly Average Sulfur Dioxide (>jg/m )
Coastal Stations Eastern - Inland Stations
Central Stations
Intermediate, Central - Eastern Stations
DATA SOURCES:
WLA - West Los Angeles (LA APCD 1969-1972)*
LB - Long Beach (NASN 1968 - 1970)
LEN - Lennox (LA APCD 1969-1972)*
SNT - Santa Ana (NASN 1969)
ANH - Anaheim (NASN 1969)
RES - Reseda (LA APCD 1969-1972)*
PAS - Pasadena (LA APCD 1972)*
DTLA - Downtown L-)S Angeles (LA APCD 1969-1972)*
SB - San Bernadir.c (SB APCD 197? & NASN 1968-1969)
FNT - Fontana (SB APCD 1972)
AZ - Azusa (LA APCD 1972)*
* Los Angeles APCD S02 data have been corrected to allow for
systematic round oft error; the LA APCD reports all S02 values from
0 to .015 ppm as .01 ppm.
Figure 2-24 Aerometric Relationship Between Sulfate and Sulfur
Dioxide in the Metropolitan Los Angeles AQCR
2-82
-------
Both the analysis of chemical transformation processes and the
empirical methods yielded the same qualitative conclusion. In response
to S02 emissions, sulfate levels initially increase above background
in a linear way. Gradually, nonlinear effects become important, and
further increases in sulfate are less than linear.
For the purpose of simplicity in control strategy evaluation for
the Los Angeles Region, a linear relation between ambient sulfate aerosol
and SCL emissions was adopted. The assumption was that measured sulfate,
minus the estimated 4yg/m3 background level, is linearly proportional to
SOp emissions. Support Document #3 examined the potential error in the
linearity assumption and concluded that the error in predicted sulfate
levels might be around 10-30%. However, since sulfate represents only
about 10% of the total aerosol mass, the error in total predicted par-
ticulate levels would amount to only 1 to 3%. This is quite small com-
pared to some other uncertainties involved in the present study. Also,
some of the error due to the neglect of the nonlinear sulfate/SO^ depen-
dence may be offset by an opposite error due to neglect of the synergistic
impact from expected decreases in HC and NO levels, (see Support Document
A
#3 for a discussion).
Nitrate Air Quality Relationship
Support Document #3 also examined the dependence of ambient inorganic*
nitrate levels in NO emission levels in the Los Angeles Region. This
A
problem directly parallels the issue of the sulfate --SOp dependence. Al-
though considerable uncertainty surrounds the relationship between sulfate
* In the aerosol classification scheme used by this study, organic nitrates
are included in the secondary organic category.
2-83
-------
levels and S02 emissions, it was found that even less is known for the
case of the nitrate -- NOV relationship. The nitrate problem appears to
A
be a more difficult one to solve, and to compound the trouble, less re-
search effort seems to have been devoted to the nitrate issue.
It is not now possible to build a sound theoretical case for the
form of the nitrate -- NO relationship because the significant conversion
X
mechanisms have not been defined and documented. Although there is evi-
dence that photochemical processes are important, the explicit photo-
chemical (or other) reactions involved in nitrate production are not well
understood.
In the absence of grounds for a systematic theoretical argument,
Support Document #3 explored the empirical approach based on atmospheric
monitoring data. Again, it was found that less work has been done with
nitrates than with sulfates. No empirical study has been published for
NOg -- NOX that is equivalent to Altshuller's work with SO^ S02 (see
figure 2-23). An attempt was made in the Support Document to perform an
empirical analysis using aerometric data from the Los Angeles Region
(see Figure 2-25). However, the results were inconclusive. For the coastal
and eastern-inland locations, the spread in NO levels was not wide enough
J\
to justify inferences about the NOZ -- NO relationship. For the central-
O A
valley stations, a straight line to the estimated NOg background level
fit well, but four data points are not sufficient to support a firm con-
clusion concerning linearity.
In summary, that existing knowledge concerning the dependence of
NOg concentrations on NOX emissions is very poor. Neither theoretical
nor empirical analysis can presently justify sound conclusions as to the
2-84
-------
EASTERN-INLAND
CENTRAL-VALLEY
COASTAL
*T__ _ ' ESTIMATED NITRATE BACKGROUND
.05
COASTAL STATIONS
A CENTRAL STATIONS
.10 .15 .20
YEARLY AVERAGE NOX (ppm)
A EASTERN-INLAND STATIONS
INTERMEDIATE .CENTRAL-EASTERN STATION
DATA SOURCE
WLA
LB
LEN
DTLA
PAS
RES
ANA
AZ
SB
UPL
West Los Angeles
Long Beach
Lennox
Downtown Los Angeles
Pasadena
Reseda
Anaheim
Azusa
San Bernardino
Upland
(LA APCD, 1969-72)
(LA APCD - NOx, NASN-NO" 1969-70)
(LA APCD, 1969-72) J
(LA APCD, 1969-72)
(LA APCD, 1972)
(LA APCD, 1969-72)
(Orange APCD-NOx, NASN-NO;, 1969-70)
(LA APCD, 1972)
(San Ben., APCD, 1972-73)
(San Ben., APCD, 1972-73)
Figure 2-25 Aerometric Relationship Between Nitrate and NO
in the Metropolitan Los Angeles AQCR
2-85
-------
form of the N(L--NOX relationship. It was decided to assume the simplest
relationship: non-background nitrate (total nitrate minus 1 ^g/m back-
ground*) was taken as_ directly proportional tp_ total NOx emission levels.
There is considerable uncertainty in the use of this linear rollback
formula; the principal justification is that there was no firm evidence
to support the use of any specific nonlinear relationship.
Ammonium Air Quality Relationship
Support Document #3 defined non-background ammonium aerosol as that
which is associated with non-background sulfate and nitrate. The air
quality relationship for non-background ammonium was taken as simple linear
rollback based on control of non-background sulfate and nitrate. Since
non-background ammonium is such a small fraction of total suspended par-
ticulate levels, (about 1 Mg/m3), the prediction of total particulate
levels should be highly insensitive to errors in the assumed NH. air
quality relationship.
Secondary-Organic Air Quality Relationship
The current state of knowledge concerning the relationship between
secondary organic levels and reactive hydrocarbon (RHC) emissions was
briefly reviewed in Support Document #3. It was found that present in-
formation cannot support any firm conclusions as to the form of the
dependence. It is not possible to base the relationship upon a theoret-
ical analysis of the reactions involved because the chemical reactions
are not well understood. Empirical models based on air monitoring data
appear to be ruled out because existing aerometric data are very de-
ficient for both the precursor (reactive hydrocarbons) as well as the
*See Table 2-13 2-86
-------
end product (secondary organic aerosol). Recent smog chamber studies
seem to indicate a linear-proportional relationship between total aerosol
formation and HC input; but this conclusion is still indefinite. These
experiments also indicate a very complex nonlinear effect v/hen the
composition of HC mixtures is changed.
It was decided to assume a linear-proportional relationship for
the dependence of non-background secondary organic aerosol levels on
I\HC emissions. The accuracy of this assumption is very uncertain;
there are no firm theoretical or atmospheric results which support the
proportional formula for secondary organics. The main justification for
the linear rollback formula is that is is the simplest and most obvious
one to assume until more evidence is gathered.
2.3.3 Illustration of the Complete Model
Section 2.3.2 characterized the origins of annual average psr-
ticulate levels at twelve locations in the Metropolitan Los Angeles
Region. Section 2.3.3 provided (linear) relationships linking the con-
tributions from controllable origin categories to contaminant emission
levels. By combining these results, we obtain a model that yields the
annual arithemetic average particulate level at each location as a func-
tion of total emission levels in the Los Angeles Region.
Table 2-18 illustrates the application of the complete model. The
left side of Table 2-1 & presents the 1972 origin classification for an
example location, Downtown Los Angeles. The center column of the table
outlines a hypothetical control strategy for primary particulates, SOp,
NOV, and RHC. The right side of the table gives the predicted impact of
J\
3
the control strategy. In this hypothetical case, the 140 /jg/m AAM in
1972 would be reduced to 78 fjg/m by the control strategy.
2-87
-------
ro
CO
CO
TABLE 2-18 HYPOTHETICAL ILLUSTRATION OF
THE MODEL FOR PREDICTING CONTROL
STRATEGY IMPACT ON PARTICULATE
AIR QUALITY LEVELS
Origin Categories
BACKGROUND CONTRIBUTIONS
(Sea Salt, Soil Dust,
Man-Made Sources exterior
to the L.A. Region, and
Background 504, NOo, and
Secondary Organics)
NON-BACKGROUND CONTRIBUTIONS
PRIMARY
SECONDARY:
so! -
NO
nriq
Secondary Orgam'cs
1972 Base Year
Origin Character-
ization for Down-
town Los Angeles
44
54
10
11
1
20
TOTAL AAM
140 yg/nf
Hypothetical Control
Strategy (% Reduction
from the 1972 Base
Year Level)
67% Reduction in
Primary Particulate Emissions
50% Reduction in S0« Emissions
50% Reduction in NOEmissions
50% Reduction in S02 & N0x
75% Reduction in RHC Emissions
Air Quality Resulting
from the Control
Strategy (ug/m3)
44
18
5
5%
78 yg/mw
-------
A Special Case: Chino
In this study, the model will be applied as illustrated above to each
location with one exception. The exception involves the primary particu-
late and sulfate contributions at Chino. For the other eleven locations
and other origin categories, the origin contribution will be changed
(rolled-back) according to total emissions in the Four-County Sub-Area.
However, for non-background primary particulates and sulfate at Chino, an
allowance will be made for localized emissions.
As explained in Support Document #3, the Chino station appears to
experience a particularly strong influence from a localized source.
This source, evidently the Kaiser Steel-Edison Electric complex, leads
to atypically high primary particulate and sulfate levels at Chino.
Estimates of the contributions from the localized source are presented
in Table 2-19. The model will be applied in a special way to Chino by
rolling back the localized origin contributions (column III in Table 2-"l9)
according to emissions from the localized source and by rolling back
the remainder (column II in Table 2-19) according to total emissions
in the Four-County Sub-Area.
Arithemetic Means vs. Geometric Means
As explained previously, this study will examine strategies for
attaining the annual national standards for particulates. These stan-
dards are expressed as annual geometric means (AGM'S), (See Table 2-4).
A problem arises since the air quality-emission level model has been
formulated in terms of annual arithemetic means. (AAM'S),* A method is
needed to reconcile the outputs of the model, (AAM'S), with the form of
the air quality standards, (AGM'S).
*The aerosol origin characterization used arithemetic means in order
to present overall linearity.
2-89
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TABLE 2-19
BREAKDOWN OF PRIMARY PARTICULATE AND
SULFATE CONTRIBUTIONS AT CHINO
Primary Suspended
Parti dilates
Sul fates
: COLUMN I
Total 1972
non-background
level*
(jjg/m3)
89
18
COLUMN II
Typical Value
for similar
stations not
strongly influenced
by the localized
source*
(yg/m3)
30
9
COLUMN III
Contribution
from the
localized
source
(II Minus I)
(jjg/m3)
59
9
* See Table 2-17,
2-90
-------
Support Document #3 examined this proble'm through an analysis of the
geometric standard deviations associated with particulate concentration
distributions. For the purposes of this study, it wad decided to replace
the AGM standards by equivalent target AAM levels. The target AAM's
3 3
were chosen as 80 ug/m for the primary annual standard and 65 ug/m for
the secondary annual standard. These target arithemtic mean levels are
"conservative" in the sense that achieving the target AAM levels will
likely result in air quality slightly better than the federal AGM stan-
dards.
Air Quality Forecasts for the Baseline Emission Projections
Tables 2-10 and 2-11 summarized the emission projections for primary
particulates, S02> NOx, and RHC from 1972 through 1980. Projections were
given for two scenarios: (1) "Present Controls", (controls presently
scheduled to go into effect by the local APCD's and the California ARB
plus the federal new car control program), and (2) "EPA Oxidant Plan",
(the present controls plus the controls called for in the EPA-promulgated
plan for oxidant in the Los Angeles Region). These projected emission
levels for the Four-County Area have been transformed into forecasted
air quality levels using the air quality model outlined above.* Air quality
projections are given for ekjht locations in Figure 2-26.
* As noted above, the model is applied to Chino in a specialized way.
The projected primary particulate and S02 levels for the local Chino
source (assuming no further controls) are as follows:
(.Kaiser/Edison Complex)
Emissions as % of 1972 level
1977 1980
Primary Particulates 150% 147%
S02 166% 163%
The details on these results are presented in Appendix A of Support Docu-
ment #3.
2-91
-------
COASTAL AREA
ro
i
ro
20ft
a
00
a 100-
0
LENNOX
Present Controls
^^ -==:=:::::=:=TPAOxidant Plan
TGJ,.
B/GND
i i
72 77 80
200
rn
e
DO
a 100-
t.
0
LONG BEACH
Present Controls
" " EPA Oxidant Plan
TGT.
B/GND
i i i
72 77 80
YEAR YEAR
CENTRAL VALLEY AREA
200
n
00
* 100
0
DOWNTOWN L.A.
Present Controls
* ~~ EPA Oxidant Plan
TGT.
B/GND
1 f 1
72 YEAR77 8°
200
^B
00
a 100*
0
ANAHE IM
Present Controls
' EPA Oxidant Plan
LUi . . ......
B/GND
72 YEAR77 8«
LEGEND:
TGT TARGET FOR PRIMARY STANDARD
Figure 2-26. Suspended Particulate Air Quality Forecasts for the Baseline Emission
Projections, (Present Controls and EPA Oxidant Plan)
-------
EASTERN- I NLAND AREA
200
72
AZ U SA
TGT.
B/GND
1
Present Controls
_.
1 ^ 1
EPA Oxidant Plan
1 1
77
80
00
a.
72
ONTAR IO
IUU
100-
n
Present Controls
EPA Oxidant Plan
TGT.
B/GND
-U. -., I 1
77
80
a
^
00
72
RIVERS!DE
IUU
100-
n
^.
TGT.
B/GND.
1
Present Controls
* .
*-^-^n
EPA Oxidant: Plan
77
80
ro
CO
LEGEND:
TGT.-
B/GND
WESTERN S A N B E R N A R D I N 0 COUNTY HOT-SPOT
-TARGET FOR
PRIMARY STANDARD
ESTIMATED BACKGROUND
300
r, 200--
p
00
a.
100-
XGL _
B/GND
72
CHINO
Present Controls
77
80
Figure 2-26.
Suspended Particulate Air Quality Forecasts for the Baseline Emission
Projections, (Present Controls and EPA Oxident Plan) (Continued)
-------
It is apparent that the projected increases in primary participate.,
SO,, and NOV emissions will lead to a deterioration of suspended particulate
C. A
air quality at most locations. Reductions in secondary orgariics (due to
decreases in RHC emissions) are sufficient to keep particulate levels
about constant in the eastern-inland area where secondary organics are
particularly important. The deterioration of air quality is especially
pronounced at Chino; with no further controls, the forecasted increase in
primary particulates and S02 from the Kaiser Steel/Edison Electric com-
plex will result in considerable worsening of an already severe particu-
late problem.**
In Chapter 4 of this report, control strategies will be proposed
for reducing primary particulate, S0?> NO. , and RHC emissions in the
» A
Los Angeles Region. The effect of these strategies on air quality will
be calculated using the linear model developed in this sections. The
goal of Chapter 4 will be to identify strategies for approaching and
attaining the national air quality standards for particulates in the
Los Angeles Region.
** Actually, some significant emission controls are planned for the
Kaiser/Edison complex, [46]. They have not been included in the
above projections because the expected emission reductions have
not yet been documented. These controls may be similar to the
controls proposed later in this report.
2-94
-------
3.0 ALTERNATIVE EMISSION CONTROL MEASURES
The development of air pollution control strategies for the improve-
ment of ambient air quality depends on a comprehensive consideration of
the various alternative emission control measures which are available
for use. This section provides an identification and characterization
of various alternative emission control measures which might be utilized
in the formulation of an air program to achieve the Ambient Air Quality
Standards for participate matter in the Los Angeles Region. This includes
an identification of emission control options for the management of gas-
eous precursors of secondary particulates, namely sulfur dioxide and
nitrogen oxides. The omission here of the consideration of emission
controls for reactive hydrocarbon precursors was justified on the basis
that the control of this pollutant species has already been the principal
subject of extensive investigation in the preparation of the State Air
Program Implementation plan.
Section 3.1 of this report includes a brief general characterization
of alternative control methods which are available for prevention of
primary particulate and gaseous precursor emissions. Section 3.2 con-
tains an analysis of the impact of applying these available control
methods to specific major source categories, in terms of control effec-
tiveness, technological practicability, and cost. The information con-
tained in these sections has been extracted and summarized from Support
Document #4,£4]-
3-1
-------
3.1 GENERAL CONTROL METHODS AVAILABLE
This section provides a brief general characterization of alternative
control methods which are applicable for prevention of emissions leading
to the suspension of participate matter in the atmosphere. A more detailed
description of these controls can be found in Support Document #4,[4]. Section
3.1.1 is a summary of the conventional control devices available to manage
emissions of primary particulates. Section 3.1.2 includes an identification
of alternative controls now available or in development to prevent emissions
of gaseous precursors. Section 3.1.3 deals with simultaneous control of
primary particulates and gaseous precursors via alternative fuels, and
Section 3.1.4 provides a discussion of emissions control by the route of
alternative administrative policies (such as shutdown, relocation, and growth
retardation).
3.1.1 Controls for Primary Particulates
Feasible control devices for emissions of primary particulates include
mechanical collectors, wet scrubbers, electrostatic precipitators, and
filters. The application of these various gas cleaning devices is based on
consideration of particulate characteristics in the gas stream, and process,
operating, construction, and economic factors. The technology of each of
the above controls is well developed, and many equipment manufacturers have
provided several generations of reliable control devices to the industry.
The table below provides a summary of the typical collection efficiency of
various control devices when used in their conventional applications.
Cyclones and settling chambers are often used as precleaners in combination
with either electrostatic precipitators or fabric filters. Wet scrubbers
can be used separately or as a precleaner. Only the electrostatic
3-2
-------
precipitator and the fabric filter are capable of removing submicron
particles with high efficiency, and these devices are used extensively
whenever strict regulations apply.
TYPICAL EFFICIENCY RANGES FOR PARTICULATE
COLLECTION DEVICES USED IN CONVENTIONAL
APPLICATIONS
Unit
Efficiency,
Percent
settling chambers
!-
large diameter cyclones
small diameter cyclones
wet scrubbers
electrostatic precipitators
fabric filters
20 - 60
30 - 65
70 - 90
70 - 99
75 - 99.5
80 - 99.5
Source: Reference [47].
The cost of preventing emissions of particulates to the atmosphere is
related to the collection efficiency of the control equipment. Table 3-1
provides a brief summary of capital costs for the various types of control
devices used to collect particulates. The two most efficient control
methods, (electrostatic precipitator and the fabric filter) appear to be
i
cost competitive for management of moderate gas flow rates. However, for
larger emission control systems, the electrostatic precipitator
demonstrates a significant cost advantage.
3-3
-------
TABLE 3-1. INSTALLED COSTS OF CONTROL EQUIPMENT
Collector Type
Gravity
Mechanical
Wet
High- voltage electrostatic
precipitator
Low- voltage electrostatic
precipitator
Fabric filter:
High temperature (550°F.)
Medium Temperature (250°F.)
Afterburner, direct flame
catalytic
Approximate Installed
in Thousands of Dol
Gas Flow Rates
(1000 Actual Cubic Feet
2 5 10 15 100
0.5 1.2 2.6 15 28
4 13 23
7.5 10 30 55
85 120
13 24 105 200
30 88 155
15 45 82
8.2 12 18 -
16 20 29 -
Cost,
lars,
per Minute)
300
-
80
150
265
-
430
225
-
-
500
-
-
-
415
-
720
375
-
-
Source: Reference [47].
The following sections provice a brief discussion of each of the
standard gas cleaning devices in terms of their operating characteristics
and applications.
Mechanical Collectors
Mechanical collectors include settling chambers and cyclones. The
settling chamber is the simplest particulate collector, typically consist-
ing of a baffle chamber in which the velocity of the polluted gas is
diminished to a level where particles settle out by gravity. Mechanical
3-4
-------
collectors are effective in removing relatively large particles. They
are usually employed as pre-cleaners to remove large particles (greater
than 43 microns) before the gas is treated by other more efficient removal
equipment.
The cyclone provides a configuration in which the polluted gas is
introduced tangentially into a conically shaped vessel that directs it
along a spiral path. Centrifugal forces push particulates of the gas
stream toward the wall, where they fall by gravity to the bottom of the
device. The inner flow of clean air travels up the center of the cyclone
and exits out the top.
Cyclones are widely employed in various industrial applications for
both pre-treatment or secondary gas cleaning operations. They are used in
fertilizer plants, petroleum refineries, mineral processing, metallurgical
operations, chemical processing, metals manufacturing, and so forth.
Met Scrubbers
Wet collectors are devices which employ liquids to remove particles
by: 1) increasing the effective size of the particles to enable efficient
collection, and 2) trapping and washing away particles in a liquid film.
This particulate-liquid interface occurs through the physical processes of
interception, gravitation, impingement, diffusion, electrostatic forces,
and thermal gradients.
There are principally two classes of wet scrubbers: the low energy
type and the high energy type. The low energy type includes
Open spray towers.
t Packed towers, in which the polluted gas and liquid
pass cross^flow through a contact bed.
3-5
-------
t Wet cyclone, in which water spray and centrifugal
forces work in combination to collect particles.
t
Flooded bed scrubbers, in which baffle grids cooperate
in aiding contact between particles and water spray.
Orifice type, in which the polluted gas is directed
through an orifice restricted by liquid spray.
Wet dynamic, which consists of a liquid spray in an
impeller cyclone.
The high energy wet collectors are commonly known as Venturi
scrubbers. In a Venturi scrubber high collection efficiency is obtained
by high velocity impingement of the gas particles with the scrubbing liquid
spray in the throat of a Venturi. The liquid is injected into the throat of
the Venturi where the velocity of the gases causes the disintegration of the
liquid to fine droplets. This disintegration enhances the probability of
contact with particulates of the gas stream.
The collection efficiency of scrubbers varies with the power input.
Table 3-2 summarizes the efficiency of the various types of scrubbers
discussed above.
Electrostatic Precipitators
The electrostatic precipitator is most frequently used to process
large volumes of gas (50,000 to 2,000,000 CFM) at large industrial
installations. In many applications, the precipitator is the only proven
high-efficiency (up to 99.9% removal) particulate control device available
today. They are used extensively to process polluted effluent gases from
smelters, furnaces, petroleum refineries, acid plants, boilers, and other
process operations.
3-6
-------
TABLE 3-2. SCRUBBER CAPABILITIES
Type of Scrubber
Open spray tower
Packed tower
Wet centrifugal
Flooded bed
Orifice
Wet cynamic
Venturi
Flooded disk
Usual Range of
Particle Sizes, Microns
10.0
10.0
2.5 '
2.5
2.5
2.0
0.5
0.5
Normal Draft Loss,
In Water
3/4-2
1-6
2-6
2-8
To 6
None
6-80
6-70
Maximum
Efficiency %
85
85
95
95
95
98
99+
99+
Source: Reference [48].
The electrostatic precipitator collects suspended particulates by
directing the polluted gas through an electrical field. The field is
established between an electrode maintained at high voltage and a grounded
collection surface. Particles passing through the field become charged
immediately and are attracted to the grounded collecting surface. The
particulate matter is dislodged from the collecting surface by mechanical
means such as vibrating with rappers or by flushing with liquids.
The electrostatic precipitator is a versatile approach to particulate
collection in that it may handle a variety of applications at very high
efficiencies. It is used to collect .particles in the submicron size
range, and is capable of operation at temperatures exceeding 1000°F, and
at pressures up to 150 psi. A distinct advantage of the configuration
of either type of precipitator is the low pressure drop associated with
3-7
-------
the gas flow path, permitting immense volumes of gas to be handled with
relatively low level of power required. Because the design of the pre-
cipitator requires considerable experience for a given application, the
industry relies heavily on the air pollution control device manufacturer to
develop equipment specifications and provide guarantees of performance.
Filter Collectors
Collecting devices based on fabric filtration are among the oldest
means of removing material from gas streams. In fabric filtration, the
particulate matter is removed from the gas stream by impinging on or adhering
to fibers of the fabric. The physical mechanism for particle collection
includes interception, inertial impaction, diffusion, electrostatic
attraction, sieving, and gravitational settling. Fabric filtration is an
effective device for removal of particles as small as .5 micron and will
remove a substantial quantity of particles as small as .01 micron.
Fabric filtration is typically accomplished by directing the
pollutant-bearing gas through flat or tubular fabric bags hanging in an
enclosure called a baghouse. The particulate material is retained on the
upstream side of the fabric while the cleaned air which passes through the
fabric is discharged to the atmosphere. The collected material is removed
from the bags by mechanical means, such as manual shaking or air shaking.
The selection of the fabric is probably the most critical aspect of
the equipment design. Determining the resistance of the filter to gas flow
for the clean fabric, and for dust laden fabric are important pre-
requisites to intake and exhaust system design. Optimal air flow ratio
through the fabric is another important consideration. Experience in
numerous applications (cement kilns, foundary cupolas, furnaces, grain
operations) have provided the baghouse device manufacturers with detailed
3-8
-------
performance characteristics cn: the many different bag fabrics and baghouse
systems. These data allow the manufacturer to guarantee high efficiency
baghouse installations in varied applications.
3.1.2 Controls for Gaseous Precursors
Gaseous emissions which play a major role as precursors to particulate
formation in the atmosphere are NOX, S02, and hydrocarbons. The following
sections provide a brief description of the most promising control methods
which are applicable to prevention of SOg, NOX, and hydrocarbon emissions.
Desulfurization of Petroleum Products
The trend toward the processing of higher sulfur crude oils coincides
with the trend of increasingly stringent emission regulations, which are
causing restrictions on the sulfur content of refinery products, as well as
on the sulfur level of refinery process emissions. These concurrent trends
obviate the need to develop additional sulfur removal facilities in U. S.
oil refineries.
Desulfurization of the heavier fractions of crudes (from diesel/No. 2
oil to heavy fuel oils) has not been extensively practiced in the U. S. to
date. The production of low sulfur products in the heavier fractions of
the crude will require catalytic hydrodesulfurization of the heavy dis-
tillates and residuum fuel oil stocks. Extensive processing of this type
has been employed in foreign countries, especially Japan. In many cases,
improved technology in desulfurization of the heavy distillates to produce
very low sulfur blend stocks has deferred the need for facilities to
desulfurize the residuum portion of the barrel. The residuum portion is
blended with the low sulfur blend stocks to obtain low sulfur fuel oils
meeting the standards.
3-9
-------
While many of the Initial desulfurization facilities were designed
to reduce sulfur levels to prevailing standards, the technology is now
available for desulfurization of vacuum gas oils to levels of a few parts
per million sulfur. Chevron claims their VGO Isomax Process, which was
first operated in Japan five years ago, is capable of sulfur levels as low
as 100-200 ppm with only moderate increases in operating severity (high
pressure and temperature) over the conditions which produce sulfur
contents of .1 - .2 percent sulfur. Figure 3-1 illustrates progress made
in the last five years in terms of the operating pressure required to
remove 92% of the sulfur from a Middle East vacuum gas oil.
900
800
700
eoo
BOO
HOC
Basis: Middle-East VGO
Desulfurizcd to
0.2.H Sulfur
UOO
300
200
1968
1973
Year
Source: Reference [49].
Figure 3-1. Continued Improvement in VGO Isomax Process
3-10
-------
Technical improvements in desulfurizati-en processes have had
dramatic effects on processing costs. Figure 3-?2 summarizes the trend to
lower costs. At current levels of technology, the Chevron Isomax Process
can produce .05% sulfur fuel oil blend stock at less cost than required to
produce .2% sulfur fuel oil blend a few years ago.
10
Base
-10
-20
'Includes amortization of onplot investment,
Hj at 60 cents/MSCF, catalyst, utilities
(Fuel at $U-/FOE Bbl), maintenance, insurance,
taxes, and operating labor.
I I I I
O.I
Product Sulfur, Wt
0.2
Source: Reference [49J.
Figure 3-2. Cost to Desulfurize Arabian Heavy Crude
Oil with VGO Isomax
3-11
-------
Typically the VGO Isomax Process has not been utilized to produce
very low sulfur content products as the standards do not generally require
this degree of operation. In fact, because of the ability of the VGO
isomax to process low sulfur fuels far below standards, a VRDS Isomax
process has been designed to complement the VGO Isomax process by providing
for moderate sulfur content fuels which may be blended with VGO Isomax
fuels to reach the higher limits of the sulfur content standards. The VRDS
Isomax is a moderate pressure, vacuum residuum desulfurization process
which will process a wide variety of high sulfur content residual to produce
sulfur products in the range of .5 to 1% sulfur content. Blending of VRDS
Isomax products with the low sulfur products of the Isomax unit provides
the most economic route for manufacturing low sulfur fuel oils meeting the
current sulfur content standards.
The VGO Isomax is an efficient tool to remove sulfur from the vacuum
gas oils of the fuel oil barrel. However it is becoming evident that low
sulfur processing of both vacuum residuum as well as the vacuum gas oil
will be needed to meet lower sulfur fuel oil requirements. There are
several processing schemes being studied as possible routes to very low
sulfur fuels (such as .05 to 1% sulfur). Chevron Research has identified
two of the most feasible methods as:
1) Solvent-deasphalting and gasification of the by-product
high sulfur SDA tar, and
2) VRDS Isomax followed by delayed coking of the VRDS bottoms
product.
In the first of the two methods, the vacuum residuum is solvent
deasphalted and then combined with the vacuum gas oil for desulfurization
3-12
-------
in the VGO Isomax process to give a 93% yield on low sulfur fuel oil.
Gasification facilities are included to convert high sulfur by-product
tar to a useful high BTU content synthetic field gas.
The solvent-deasphalted oil is more difficult to desulfurize in the
VGO Isomax Unit than the straight run vacuum gas oil above. However the
blend of the two oils does not require appreciably different processing
conditions than those which are used in existing commercial VGO Isomax
Units. The VGO Isomax Plus solvent-deasphalting process is well established
and has been operative at the Standard Richmond Refinery over the past eight
years. Experience has shown that high yields of low sulfur fuel oils can
be obtained.
In the second of the two methods above, vacuum residuum is processed
in a VRDS Isomax Unit and the higher boiling products are sent to a
delayed coker. The lower boiling fractions (975°F) are combined with the
vacuum gas oil for desulfurization in the VGO Isomax to result in the
desired low sulfur fuel oil. This process provides a 93% yield of fuel oil
from high sulfur Arabian residuum. Metallurgical quality coke is removed
as a useful by-product from the delayer coker.
Chevron Research has demonstrated the two processed above with pilot
plant studies using difficult high sulfur feed stocks such as Arabian Heavy.
Results of test runs show that refineries can process high sulfur crude
while maintaining product quality and meeting environmental standards. Both
processes lend to stepwise construction at the refinery. The VRDS Isomax
and the VGO Isomax can be integrated into existing refineries with delayed
coking and catalytic cracking facilities.
Cost comparisons reveal that initial capital investment is similar
for the two low sulfur processing approaches. In terms of processing costs,
3-13
-------
the Isomax VGO/VRDS plus delayed coker method is superior by about 36 cents/
barrel of low sulfur product over the Isomax VGO/Solvent-Deasphalting plus
gasification procesr plan. Process costs depend somewhat on the market
demand for the by-products of the two approaches, which tend to fluctuate
greatly. Initial investment and manufacturing costs for the two
desulfurization schemes are outlined in Support Document #4, [4].
SOg Removal Technology
Commercial methods for desulfurization of tail gas from sulfur plants,
stack gases, and other effluent gas streams amount to some 20 techniques
which are representative of more than 50 identifiable processes. These
SOp removal systems are in various phases of development and the number of
actual applications have been limited to date. Because of performance
uncertainties associated with the infant SOp control systems, industry is
not rushing to purchase these expensive systems, despite the approaching
clean air deadlines.
Virtually every desulfurization control process has its own chemical,
engineering, economic, and operating peculiarities. Some processes are
particularly suited to meet one set of plant effluent conditions, while
another S02 removal process may be best adapted to an entirely different
set of plant parameters. Since there are probably as many different plant
effluent-gas-stream types as there are plants emitting gases, the
combinations of effluent stream and desulfurization techniques are
practically unlimited.
In the long term, radical new technologies may lead to entirely
different process systems which are compatible with the ambient air quality
goals. However until such new technology is available, "add on" control
3-14
-------
systems are a more likely candidate method for achieving the imminent and
stringent future S02 emission regulations. Table 3-3 provides a descrip-
tion of 14 of the principle techniques now being adapted or considered for
S02 removal in different process effluent streams. The choice of
technique in any application depends on the nature of the gas stream being
treated and a variety of engineering and economic factors related to each
situation.
Sulfur can exist in a large number of oxidation states. The common
oxidation states of sulfur found in process effluent gas streams are those
typified by H2S (-2), elemental sulfur (zero), S02 (+4) and S03 (+6).
The reduction-oxidation interconversion of sulfur between the oxidation
states -2, 0, +4, and +6 is an essential feature of current and proposed
desulfurization processes. In each of the processes the objective is to
produce a sulfur product which may be removed mechanically from the
system. This corresponds to an oxidation state of either zero (elemental
sulfur) or +6 (sulfuric acid and sulfates). To convert the various
oxidation states of sulfur existing in an effluent gas, a wide range of
oxidizing and reducing agents is used. The conversion route may involve
an indirect pathway, such as +4 to -2 to zero as in the Beavon Process,
+4 to +6 in the Mitsubishi Process, and other variations as shown in
Table 3-3.
Characterization of the effluent stream is the first step in
selection of an appropriate desulfurization process. Effluents from
combustion sources such as power generating stations are rich in S02 with
little or no hLS content due to prior oxidation incineration. These
conditions would tend to encourage the use of processes that handle S02
3-15
-------
TABLE 3-3. PROCESS FOR DESULFURIZATION OF EFFLUENT GAS STREAMS
PROCESSED PRINCIPALLY IM THE GAS PHASE
Process
(Developer)
Comments
Process Chemistry
1.
2.
3.
4.
5.
YIELDING SULFURIC
Dry limestone
(TVA)
Manganese dioxide
(Mitsubishi)
Active magnesia
(Showa Hatsuden)
(Chemico)
Modified contact
Activated carbon
ACID OR SULFATE {(S = + 6)
Simultaneous reaction of SOg with lime and SO , SO , AIR
flir oxidantion of resulting sulfite to sul- CaCO CaO 23 ^ ^^Q
fate. End product slag requires suitable ^ " ""^
disposal. Swedish Bahco Process uses
hydrated lime slurry. Lignite ash also used + C02 (TO ATMOSPHERE)
as absorber (Carl Still, W. Germany).
Initial concentration and oxidation of SO? to S02 n-n » MnSO* -TnT*" (NHJ, SO, + H,0
metal sulfate with air regeneration of Mn02 -2 A1K * ^ 4 i
oxygen carrier and ammonium sulfate (fer- j
tilizer) production. REGENERATION
Essentially a concentrati.on process using rn 200°-300°F urcn 1400°F 1ca, cri rne
MgO as a "collector" followed by regenera- °°2 MGD * 3 "" * 2
tion of concentrated S02 stream for sul f uric ( 1 CONTACT
acid plant reea. REGENERATION * PROCESS
Essential Contact Process yield acid onnOc 2 ^
(Monsanto) or ammonium sulfate (Tokyo) but AIR i SO » SO ^ II rO
accepts hot dilute S02 gas stream rather 2 V2°5 ,3 H2° 2 4
than high S02 acid plant feed. (See also | , .
lopsoe Process) 2NH.OH "~ ^M4^°4 + H2°
All methods depend on absorptive powers of
various forms active carbon to first con- AIR H Q
rentrate and then catalvze exidation SOo r^r\ HIK, ng ^^ ^.,
v.ciiiiai.c anu mcii v.ai.aijr<.c cAiuakiuii ou^ j(j nrTT\ic rADDnM ^^ "3JU/I
to S03 for acid or sulfate production. 2 ACTIVE CARBON 2 4
Fluidi zed, fixed and plugged flow beds
variously employed
co
i
-------
Process
(Developer)
TABLE 3-3. PROCESS FOR DESULFURIZATION OF EFFLUENT GAS STREAMS (CONTINUED)
Comments Process Chemistry
6.
7.
8.
9.
10.
YIELDING SULFUR (S = ZERO)
Sulfreen . Catalytic use of active carbon for high
(SNPA-Lurgi) efficiency Claus redox reaction to yield
Clll-flir v-Thhrtv -f-h-in /-> vi H -» lit -i r\n nf Cfin t,-, HP 4- ^fi _....,., »_ IJ f\ .1. C
Alkalized alumina
(U.S. Bur. of Mines
discont.) U.K.
Cent. Elec. Board
Processes
Molten salt
(Atomics, I ntn'l)
(Garrett, Res.&
Dev.)
Solution Claus
(Inst. Francais
du Petrole)
Giammarco-
Vetrocoke
S64=: Requires both H2S and S0; InStreara. 2 2 ACTIVE CARBON 2
Concentration of dilute SOp stream on cn Al203/NA20
Alk/alumina and in situ catalytic reduc- 2 56% 37% * ML-UKLLU -u2
tion to HoS using reformer Hb, HS then f u . rn
to Claus with regenerated S02. REGENERATION | "2 J LU
r ^ ii r i rn rcrrnpMrn
With At Least One Principal Solution Staae LLMU;> ^
-0 + HCO (L) 430°C ^M -0 + CO
Dilute S0? concentrated by absorption S ^ ' H? + CO NATURAL GAS
in inolLen sdlL as sulfiLe arid reduced i CLAUb *^ KthUKMAiL
by H2 (Atomics) or coke roasting (Garrett) H20 OR COKE ROASTING
to sulfide and hence H2S. Both processes ' f
feed Claus. H,S + M,CO,(L) *- M,S + H,0 + C0?
L. t J £ U C
* 1
STEAFT + C02
Essentially Claus redox in solution with MFT., <- ., T r»Tfll V<-T
nv- uiithr.nl- nrlrlorl rit-iTuct Hinh hm'Tlnn II r 1 rO » 1 + H 0
01 without added catalyst. High boiling ll^ i M2 POLyGLYcOL SOLVENT (M.W. -400 2U
solvents preferred to accept hot gases
without extensive cooling.
thioarsenite with arsenate/arsenite air 1
regeneratable redox couple as oxygen T
carrier. Several similar systems in- -,,,., . Q r , y\\ A-Q « KH0AsS3 + 3KH2ASO/I
volving inorganic redox couples (thylox, 2s 3J X2°3 " 1
manchester, lacykeller exist. I
ISO^flTP^ I_^+3S
I
>>l
-------
TABLE 3-3. PROCESS FOR DESULFURIZATION OF EFFLUENT GAS STREAMS (CONTINUED)
Process
(Developer)
Comments
Process Chemistry
11.
12.
13.
14.
YIELDING SULFUR
Stretford
U.K. North W.
Gas Board)
Well man-Lord
Beavon
(Parsons Co. )
Cleanair
(Pritchard)
(IGS)
(S = ZERO) (Continued)
Solution oxidation of H2S absorbed as H?S + Na?CO^ »- |NaHS + NaHCO.,
Bisulfide by two stage redox couple
involving vanadate and anthraquinone S + Na2V?0 + Na?CO. + H?0 + NaVO,
disulfonic acid as oxygen carriers i -to c. $
Takahax uses napthaquinone. I pcnnv '
AQDSA(02) AQDSA
i AIR 0 1
A solution method for concentratina SO + II 0 t M SO » ?MHSO fSOIN^
dilute SO, steam to rich feed for Claus . i ~zf J pcniccni uc *
bv bisulfite formation crystal! izatlnn SO + H 0 + M SO .»,.., ?MHSO OfXSTI \
and thermal regeneration. No reduction "
or oxidation in solution step. . pTrH
II f; ,1 .__.,. ,,. n MK , ^_ t;
H2J FEED TCT LLAUo d
Prhliminnrv an^ nhn^n rntnlvtir hvrfrn fH \ ^fl Cfi^ f^ , / ° ^"J. _. H ^
genation all sulfur compounds to HoS i
COS and CS2 reduced. $^ STRETFORD »
HoO
continue Claus^and hydro lyze COS and 2' '* 2> ' 2 COOLING 2 2
CSo; final HoS to Stretford.
FURTHER CLAUS
S -* STRETFORD J
co
Co
Source: Reference [50].
-------
directly and alone. In processes where effluents consist principally of H2$s
such as from oil refinery sour gas processing, those processes designed to
treat H2S alone or both H2S and S02 together may be preferred. Of course the
H2S may be incinerated to S02 alone, but this leads to dilution of the
effluent and complicates the control process by introducing larger
processing volume requirements.
t End Products of Desulfurization Systems:
All desulfurization processes yield an end product.
In some of the processes the product is marketable.
Sulfur is the end product in many of the cleanup
processes (particularly those applied to sulfur
recovery tail gas at oil refineries), and finds wide
use as a base chemical. Its marketability fluctuates,
and its low dollar-per-ton cost does not begin to
enable the cleanup system to pay for itself. However
because of its marketability and relative ease of
handling, sulfur as an end product may be disposed
of conveniently.
The disposal of sulfuric acid as an end product is
complicated by storage problems. Large tonnage
storage or long distance hauling is not feasible.
Selection of desulfurization cleanup systems
yielding sulfuric acid as an end product depends
on the presence of a consumer near the
process.
Disposal of ammonium sulfate (the end product in
processes such as the ammoniacal solution and man-
ganese dioxide technique) may be costly when moisture
protection during storage is required. It can then
3-19
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find immediate use as a fertilizer.
Calcium sulfate, an end product of the
dry-limestone process, is a waste requiring land
fill disposal.
Water wastes are a disposal problem with all of
the large-volume aqueous solution processes.
Large volumes of contaminated water must be
repurified before recycling or discharging as
effluent.
The Wellman Lord cleanup process yields a sodium
sulfate which is nonregenerable. Its handling
does not pose a problem, but the current market
for this process is limited.
0 Process Efficiency:
Performance data for the various desulfurization
processes is rather limited, except as each of
the processes relates to particular applications
now prevalent in the field. In this respect a
number of the cleanup processes have proven suit-
able for SO £ removal down to concentrations of
less than 500 ppm. Initially, desulfurization
processes were applied successfully to the tail
gas of Claus units at oil refineries. Several
units have been operating successfully at
various refineries for the past few years.
SOU cleanup processes have also been installed
3-20
'to
-------
in Los Angeles, reducing emissions from refinery tail
gas to less than 500 ppm as required by new regula-
tions imposed by the APCD. Among those processes capable
of reducing SOg levels well below 500 ppm in effluent
gas streams are the Vetrocoke, Stretford, and Wellman-
Lord process. These processes have operated in various
tail-gas applications to reduce SOp concentrations to
less than 200 ppm.
Motivated by imminent new SOp emission standards tar-
geted for the electric utilities, several power plants
have now been equipped with desulfurization systems
which are providing continuous operation at 90% plus
S02 removal rates. Table 3-4 provides a summary of
nine different cleanup processes now under test at
various utilities. In Los Angeles, APCD S0? envissiom.
regulations are met by the electric utilities burning
low sulfur fuels, stack emissions are kept under the
permissible 2000 ppm SOp emission level (Rule 53, Sul-
fur Compounds Concentration). This control procedure
permits relatively low sulfur emissions to be achieved
without the need of costly add-on desulfurization sys-
tems. However, unless desulfurization of fuels is
extended to lower limits, the sulfur removal effected
by this strategy may not be satisfactory to meet the
moving clean air targets. Add-on desulfurization
equipment may then become a candidate control measure
for power utilities located in the Four-County Area.
3-21
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TABLE 3-4. S02 REMOVAL PROCESSES CURRENTLY IN TEST
Process
Lime scrubbing
(boiler injection)
Lime scrubbing
(scrubber introduction)
Limestone scrubbing
Magnesia scrubbing
Catalytic oxidation
Sodium salt scrubbing
(thermal regeneration)
Sodium salt scrubbing
(throwaway)
Manganese oxide
absorption
Carbon adsorption
Approx.Test
Unit Size, Mw
120
120
117
150
100
125
125
110
150
Developer
Combustion
Engineering
Chemico
Babcock & Wilcox
Chemi co-Basic
Monsanto
Wellman-Powe'r Gas
Combustion
Equipment
Associates
Mitsubishi
Hitachi
Utility
Kansas City
Power & Light
Mitsui Aluminum
(Japan)
Kansas City
Power & Light
Boston Edison
Illinois Power
Northern Indiana
Public Service
Nevada Power
Chubu Electric
Power (Japan)
Tokyo Electric
Power (Japan)
Source: Reference [51].
Cost:
Under the new federal regulations, electric utilities
are the main target for SOp and control systems. The
Sulfur Oxide Control Technology Assessment Panel has
estimated that the cost of S0~ stack cleaning for
power utilities could increase consumer cost for
electricity by 17%. Several utilities have affirmed
that S02 cleanup technology will increase consumer
rates by 20%. The Louisville Gas and Electric Company
3-22
-------
has stated the cost of its announced SCL com-
pliance program for its eight existing units will
amount to a rate increase of 30%. Some examples
of the capital cost of retrofitting S02 cleanup
technology in existing power generating plants are
shown below:
Size of Plant
(MW)
800
550
65
1650
Initial
Capital
150
42
3.1
100
% per KW
60
80
50
60
Developer & Utility
Penn Power, Bruce Mani field
Station (2 units)
TVA, Widows Creek
Louisville Gas & Electric
Louisville Gas & Electric
(8 units)
Although numerous cost estimates have been made
for cleaning stack gases, most of the published
information is not definitive. It is difficult
to evaluate and compare the cost of cleanup
processes when there are still many problems to
be identified during development. This situation
will be remedied as current projects are completed
and more operating data has been obtained. In
addition, costs will vary widely depending on factors
such as plant size and location, cost of raw
materials, difficulty of product disposal, and
whether the installation is new or retrofit. The
3-23
-------
present indication is that for power plants
investment can be as high as $80/KW with an
annual operating cost as high as $2.5/KW.
The costing of desulfurization cleanup systems
used to control emissions from the tail gas of
Claus sulfur recovery plants involves less guess
work than other applications. S02 removal pro-
cesses have operated continuously with high
efficiency at several sulfur recovery plants for
the past few years. A high efficiency cleanup
system for a typical C3aus unit processing
1000 tons/day of sulfur with a tail gas S02
concentration of 10,000 ppm would incur a capital
cost of $3.5 million.
The problem of high cost for stack desulfurization
is compounded by the limited availability of the S
cleanup systems. The Sulfur Oxide Control Tech-
nology Assessment Panel has stated that processes
may not be readily available for the next few
years. Currently there are several scheduled
process installations, and if projected emission
control standards are implemented in the next few
years, commercial demand for the cleanup systems
will far exceed the industry's limited manufac-
turing capacity.
3-24
-------
3.1.3 Alternative Fuels - A Control for Particulates, S02 and NOX
Today's energy needs are served primarily by direct use of fossil
fuels. The disappearing reserves of these fuels for low cost energy,
and the concern over long-term energy supply, has recently given rise to
investigation of alternative energy systems by various energy planning
agencies. Synthetic fuels from non-fossil sources are now being advocated
as the most suitable alternative for supplying the long term needs for
gaseous and liquid fuels. However, in the near term, until technology is
more advanced, even synthetic fuels will require fossil sources such as
coal and oil shale.
A conversion to synthetic fuel systems would have dramatic impact
on air quality problems. Consumption of synthetic fuels in these systems
results in very little air pollution, and would eliminate the immense
effort now targeted for control of air pollutant emissions from fossil
energy use.
Among the comprehensive studies of potential fuels, methanol is
described as the most desirable of the alternatives in many ways. Hydrogen,
which has been suggested as a universal, nonpolluting fuel, is expensive,
difficult to store and transport, unadaptable to current fuel-using
equipment, and hazardous; the use of methanol does not pose these
problems.
Methyl-fuel can serve as a substitute in many current fuel systems.
In full scale boiler combustion tests, methyl-fuel has proven itself an
effective air pollution control measure. The burning of methyl-fuel
produced virtually no unburned hudrocarbons, S02, or particulate emissions,
and NO emissions were reduced below that produced under firing of natural
J\
gas. Methyl-fuel is especially attractive as a fuel substitute for motor
3-25
-------
vehicles, and can be utilized as an additive to current fuel stocks without
special adaption. Its research octane blend value of 130 makes it a possible
octane booster substitute, and because it has no lead or sulfur it can be
used compatibly with motor vehicles equipped with catalytic exhaust
control devices. When methyl-alcohol is used as a complete motor fuel sub-
stitute (requiring engine adaption estimated at $100 per vehicle), exhaust
emissions are reduced by 80%,[52],[53].
Methanol is produced by reacting synthesis gas (CO, C02, and H2) at
various temperatures and pressure in the presence of a catalyst. In the
typical commercial production of methanol, the synthesis gas is produced
by reacting steam and methane. However the synthesis gas can also be
produced from natural gas and carbonaceous materials such as oil shale,
coal, and refuse. In the manufacture of methanol the output can be
increased by 50% if small amounts of other alcohols can be tolerated in
the product. Such a mixture is called "methyl-fuel," and can be produced
in larger quantities and lower prices than pure methanol, and has
superior properties as a fuel.
In the near term, coal must be utilized to achieve large scale
methyl-fuel production. However the desirability of coal for methyl-
fuel production depends heavily upon successful coal gasification
design. Intensified development is now under way to provide these designs,
and some have proven feasible already. These systems are similar to those
already built on commercial scale for the U. S. Bureau of Mines and
various chemical companies.
Economics of Methyl-Fuel Production:
In the past two years, dramatic changes have occurred
in the world economic situation, affecting the cost of
3-26
-------
many types of raw materials. The price of pet-
roleum has increased by a factor of five, and
costs are now rising to reflect the increased
demand for coal. While the current uncertainties
in the marketplace suggest restraint in economic
projection, it does appear that the current trend
is pricing alternative fuels into competition.
The cost of fuel oil to the fuel-burning utility
companies is presently $15 per barrel, or $2.46 per
million BTU.
One of the principal drawbacks to the immediate use
of methyl-fuel as a substitute in fuel combustion
equipment is its availability. Currently the
projected market for this fuel is limited. In
addition, it may be difficult to provide the coal
resources needed for expansive manufacturing
of methyl-fuel. The nation is currently engaged
in a program toa increase utilization of coal for
generation of electric power, and limited coal
availability has already placed uncertainties on
that effort. Environmental concern over land
abuse by coalmining is a primary constraint to
plentiful coal supply. However, an advantage con-
tained in the methyl-fuel production is that it will
use "low quality" lignite coal, a cheaper and lower
demand coal.
3-27
-------
In addition to material supply problems confronting
any immediate plan for large scale product-on of a
substitute fuel, there are obvious social and poli-
tical disruptions inherent in a plan proposing
radical manufacturing arid consumer conversions. If
air quality standards are to be met in the near term
through fuel conversion policy, the disruptions are
inevitable, and probably, intolerable. However, if
environmental standards are promulgated to promote
alternative fuels over the long term, the transition
would appear to be feasible. The market demand may very
well supplant this long term possibility. It has been
estimated that by 1975 there will exist a market for 18
methyl-fuel plants by coal gasification. By 1980 the
demand will be 28. According to the Vulcan-Cincinnati
Company, who has a proprietary hold for the manufacture
of methyl-fuel, it would be possible to construct these
fuel plants by 1980. By 1990 the market demand is
projected at 120 plants,[53].
In the long term, methyl-fuel conversion appears
practical. In fact, the apparent far reaching
attractiveness of methyl-fuel conversion as a long
term approach to air resources management problems would
seem to raise serious questions as to the sensibility of
current air quality achievement goals predicated on
rapid timetables. In the long term, deferment of
3-28
-------
present short term air quality objectives could
have significant impact on the rate of development o
of far reaching alternatives such as methyl-fuel
substitution. More investigation is needed to
determine the relationship between these factors.
3.1.4 Non-Technological Control Measures
The total regional emission rate from a certain type of air pol-
lution source can usually be described as a product of three factors:*
/ Total \ / Number of \ /Average \ /Average \
i Regional l _ / Source Units] I Source i / Source \
I Emission I I in Region / I Usage j I Emission I
\ Rate / \ / \ Level / \ Factor /
The controls considered so far in this chapter have essentially dealt
with methods for reducing the last of these three factors. The above
controls have consisted of modifications of processes or additions of
cleaning devices so as to reduce average source emission factors. As
such, they might be called "Technological" controls.
This section will briefly examine "non-technological controls",
that is, controls aimed at reducing source numbers or source usage.
Source relocation and growth restrictions will be the two methods examined
for decreasing source numbers. The discussion of source usage control
will emphasize vehicle use reductions, i.e., vehicle miles travelled
(VMT) restrictions.
*For example, regional NO emissions from motor vehicles (say in tons/
day), equal the number or vehicles times the miles travelled per vehicle
per day times NO emission per vehicle mile.
J\
3-29
-------
It is not unappropriate that non-technological controls are considered
last in this chapter. As will be evidenced by the discussions below,
there are very great socio-economic costs and implementation problems as-
sociated with non-technological controls, especially when they are con-
sidered over the short-term, (say 5 to 10 years). It may be difficult to
implement strict technological controls for motor vehicles, aircraft,
power plants, or industries. However, the resistance to measures such as
50 percent VMT reduction, industry relocations, or a no gravity policy
can be much greater. On the short-run, non-technological controls are
somewhat a last resort. They sould be considered here, however, since
very large reductions in total emission levels will be needed to approach
the national air quality standards for particulates in the Los Angeles
Region.
Growth Restrictions
Control measures which limit community growth provide an important
means of maintaining air quality. These measures may be geared toward
discouragement of new growth (disincentive measures) or toward total
prohibitions. Alternative measures providing disincentive to growth have
been outlined in a recent TRW study on Air Quality Maintenance for the
San Diego Area, [54]. The measures include various restrictions on land
use such as special residential zoning ordinances, environmental impact
reporting, special taxation rates, open space planning, and capital
improvements requirements. The severity of the restrictions is established
to reflect the degree of growth control needed to maintain air quality
levels within standards.
Due to the substantial magnitude of the air pollution problem in
the Los Angeles Area, it may be necessary to consider implementation of
3-30
-------
control measures which would actually prohibit certain types of growth.
These prohibitions might be directed at the more significant sources, and
could include such restrictions as a limit on motor vehicle registrations,
prohibitions on industrial expansion, prohibition of airport expansions,
limits on utility service hook-up, etc.
Relocation
Source relocation is potentially a very effective method for reducing
total regionwide emission levels. However, unless one is moving significant
portions of the human population out of the air basin, (which some may
agree is the step that is actually necessary to attain all present air
quality standards in Los Angeles), source relocation appears to be most
appropriate for large, concentrated sources. It is usually a much more
difficult problem to relocate area sources, such as traffic, residence,
etc. Accordingly, in this study, relocations will be considered only for
concentrated or ooint sources.
The major candidates for relocation in the Los Angeles area are the
international airport, power plants, refineries, and certain large in-
dustries. The re-shifting of any of these facilities would invalue a
tremendous cost and would be resisted by very strong political forces.
It is not within the scope of this study to examine these costs and
implementation problems in detail. Rather, this study will just note
the amount of relocation that may be necessary to meet the air quality
standards. If relocation is actually chosen by control agencies as a
viable measure, further study will have to be given to the impact associated
with its implementation.
3-31
-------
Source Usage
Restriction of source usage rates is potentially a very effective
method of reducing emissions. Examples would be limits on power plant
operating level, refinery throughout, or motor vehicle travel. Usage
limits for large stationary sources would be equivalent to growth control
(for slight restrictions) or to partial relocation (for severe restrictions)
The following discussion will concentrate on use controls for motor vehicles
Recent transportation studies have examined the effect of alternative
policies for reducing vehicle miles travelled (VMT), [55], [56], [57].
The list of potential measures which have been studied include the
following:
§ Improvements in bus services
New rail transit service
« Auto free zones
Increased parking costs
Carpool promotion
t Exclusive bus and/or carpool lanes
A study for Los 'Angeles indicates that each of these measures (when carried
out at a reasonable level) would produce only marginal reductions in VMT,
(from .1 percent to 5 percent), [55]. A comprehensive program comprised
of all these would only be expected to reduce VMT by 10 to 20 percent.
In order to produce larger changes in VMT, say on the order of 50 percent,
gasoline rationing appears to be the most appropriate step. The reader
is referred to references [55], [56], and [57] for a detailed discussion
of potential VMT reduction measures and their impacts.
3-32
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3.2 SUMMARY OF CONTROL ALTERNATIVES FOR EMISSION SOURCES IN THE FOUR
COUNTY AREA
This section provides an identification of those alternative control
methods of Section 3.1 which may be applied to specific emission source
categories in the Four County Area. Tables 3-5, 3-6, 3-7 and 3-8 contain
a summary of these control options for the control of particulates, S02,
NO , and reactive hydrocarbons (RHC), respectively. Included in the first
J\
three tables is: 1) an assessment of the emission control impact of each of
the control methods, in terms of the emission reductions expected from the
control in 1977 and 1980, 2) a tabulation of the cost effectiveness of
the control measures, and 3) the baseline projected emission inventory for
the various source categories when the EPA oxidant plan is implemented.
Since no additional controls were examined to be added to the EPA oxidant/
RHC control program, Table 3-8 presents a summary of the RHC emission in-
ventory only.
Various air pollution control techniques were identified in the study
as candidates to improve the control of emissions from the major source
categories. The most significant emission control options identified are:
1) desulfurization of petroleum products to very low sulfur levels, 2)
alternative fuels, 3) S02 removal processes, 4) motor vehicle particulate
traps, 5) fabric filters or baghouses, and 6) electrical precipitators.
The first three control options listed above each represent a relative-
ly new state of the art in emission control technology. Desulfurization
of petroleum products to very low sulfur content has been practiced com-
mercially in very few applications. However, the technology has been proven,
and it appears to be suitable for the production of very low sulfur fuel
oils, and for motor vehicle fuels with sulfur contents below 100 ppm.
3-33
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TABLE 3-5
ALTERNATIVE CONTROL MEASURES FOR PREVENTION OF
PARTICULATE EMISSION IN THE FOUR-COUNTY AREA
PARTICIPATE BASELINE
EMISSIONS
TOTAL
1972 1977 1980
M.9 83.5 86. 1
-_ .
12.3 12. 5 '.2.8
B5.4fl71.4d69.2d
SUSPENDED
1972 1977 1980
44.7 82.6 85.2
11.2 11.4 12.0
72.1d63.6d64.2<)
SOURCE CATEGORY
Petroleui Industry
Stationery Fuel
Combustion
" ~
Minerals Industry
Motor Vehicles
Processes
Industry
CONTROL MEASURE
1) throve efficiency
of regenerator unit
dust control system
fro* 9SX to 991 (by
upgrade of p red pi-
ta tor).
2) Require SO? removal
equipment for stick
control (901 remov-
al) of regenerator
unit.
1} High efficiency
electrostatic pre-
clpttatlon on power
plant boilers.
large nan-power
plant boilers, and
refinery heaters.
2) High efficiency
baghouse for appli-
cation on power
plant boilers.
large non-power
plant boilers, tnd
refinery heaters.
3} Desulfurlzatlon of
fuel oils to .051
5 with new desul-
furization technol-
ogy. To be applied
to power plant
boilers and large
non-power plant
boilers.
4) Fuel conversion to
methyl-fuel in all
combustion units
which can use fuel
oil.
- Ho significant
alternative
Identified.
chamber redesign
In turbine engines.
turbine aircraft
ground operations -
towing of aircraft
to avoid taxi Idle
emissions.
3) 1 and 2 above.
1) Remove lead In all
motor fuels.
fuels to 100 ppn
sulfur content.
3) Equip motor vehic-
les (without cata-
lytic converters)
with partlculau
traps.
4} Equip all motor
vehicles w1thS02
scrubber.
5) (2) and (3) above.
(Desulfurlzatlon and
partlculate traps.
6) (Z) and <4> above.
(Desulfurliatlon and
SO, scruboer/partl-
culate trap).
spray booths with
water wash.
hiving uncontrol-
led paniculate
emissions with bag
house.
alternatives
Identified.
'ARTICULATE EMISSION
(EDUCTIONS TONS/DAT)
TOTAl
1977 1980
1.8 l.fl
.7 .7
64.6 61.7
67.9 64.7
12 23
65
0 0
13.6 19.6
9.8 7.3
46.8 44.3
40.5 37.4
48.4 46.3
iCSPEHDCD
1977 1980
1.8 1.8
.7 .7
63. B 60. 9
67.1 63.9
11.3 22.3
64.3
0 0
12.9 18.6
S.I 4.3
42.1 41.4
34.7 31.6
44.0 43.3
COST EFFECTIVCKtSS
(Cost per Ton of
Paniculate
Emissions
Preventtd)
$512
1193
11520
$1540
114100"
$5730
$4)00*
1300*
$2930 '
M75
t
$4630«
12260
16300
17Z4
$1242
-
b. The cost of air pollution control benefit! ire figured for four-County Area only, and do not
reflect the tons of emission reductions due to operation of the controlled aircraft fleet In other
a. Includes airborne partlculatei arising frtm tire wear.
3-34
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TABLE 3-6
ALTERNATIVE CONTROL MEASURES FOR PREVENTION
OF S02 EMISSIONS IN FOUR-COUNTY AREA
BASELINE SO, EMISSIONS
TONSXDAY
1972 1977 1980
60 60 60
208 374 380
1.4 1.7 1.8
3.4 6.5 9.6
48.9 46.1 47.0
13.0 15.0 15.9
97.0 10.0 10.1
SOURCE
CATEGORY
Petroleum
Industry
Stationary
Fuel
Combustion
Minerals
Industry
Aircraft
Operations
Motor
Vehicle
Organic
Solvents
Metallur-
gical
Processes
Chemical
Industry
CONTROL MEASURE
1) Require SOj removal equip-
ment for stack control.
2) Require desulfurization
(to .05% S) of all petro-
leum feed to catalytic
cracker.
1) Desulfurize petroleum
residuum to obtain fuel
oil with sulfur content
of .05%. To be applied
to power plant boilers and
large non-power plant
boilers.
2) Equip all combustion
equipment stacks with SO.
removal systems.
3) Fuel conversion to methyl-
fuel in all combustion
units which can use fuel
oil (power plant boilers,
iron-power plant boilers,
and refinery heaters).
4) (1) above, and SO? remova
systems on all refinery
heaters.
No significant alterna-
tives identified.
1) Modification of turbine
aircraft ground opera-
tions. Tow aircraft to
avoid taxi emissions.
1} Desulfurization of motor
fuels to 100 ppm sulfur
content.
2) Equip all motor vehicles
wi th S02 scrubber.
None required as this
source category does not
account for significant
S02 emissions.
1) Equip all furnace efflu-
ent stacks with SO. re-
moval systems.
No significant alterna-
tives identified.
(Control of sulfur re-
covery plants by local
agencies has accounted
for the substantial re-
ductions between 1972
and 1977.)
SO. EMISSION REDUCTION
TONS/DAY
1977 1980
51.4 51.4
51.4 51.4
168a 308
336 342
379
201 342
0 0
1.4 2.1
35.5 35.3
43.8 44.6
13.5 14.3
COST
EFFECTIVENESS
(Cost per Ton
of SOg Emission
Prevention)
$193
$964
$1040
$1540
$1030
$1075
-
$750b
$1680°
$4950°
$101
a. Due to long lead time requirements for design and construction of desulfurization equipmen', it
was assumed that only 1/2 of the required desulfurization plants could be available by 1977.
b. This control measure is proposed for the control of other types of emissions in addition to SO-,.
c. The cost effectiveness figure may be misleading since this measure is proposed as a control for
both particulate and SO^ emissions.
3-35
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TABLE 3-7. ALTERNATIVE CONTROL MEASURES FOR PREVENTION
OF NOV EMISSIONS IN FOUR-COUNTY AREA
/\
BASELINE NOX EMISSIONS
TONS/DAY
1972 1977 1980
67.5 67.5 67.5
282 672 629
18.6 32.2 45.4
950 815 665
.5 .6 .5
.4 .5 .5
SOURCE
CATEGORY
Petroleum
Industry
Stationary
Fuel
Combustion
Aircraft
Operations
Motor
Vehicles
Organic
Solvents
Metallur-
gical Pro-
cesses
Chemical
Industry
CONTROL MEASURE
No significant alterna-
tives Identified.
1) Initiate low excess air
firing and flue gas re-
circulation for small
power plant boilers, and
large/medium sized non-
power plant boilers.
2) Low excess air firing
for refinery heaters.
3) Water Injection or ex-
haust gas recirculation
for stationary internal
combustion engines.
4) Fuel conversion to me thy 1-
fuel in all combustion
units which can use fuel
oil (power plant boilers,
non-power plant boilers,
and refinery heaters).
1) Water injection
2) Major combustion chamber
redesign.
3) Modification of ground
operations. Tow aircraft
to avoid taxi emissions.
4) (1) and (3) above.
No significant alternatives
were identified in addition
to those already scheduled
under the local, state, and
federal clean air programs.
NO EMISSION REDUCTIONS
* TONS/DAY
1977 1980
0 0
242 227
26 24
66 62
328
13.9 20.5
8.1 12.0
2.1 3.2
14.8 22.8
0 0
COST
EFFECTIVENESS
(Cost per Ton
of NO, Preven-
tion)
-
$588
$111
$18
$1190
$820
$5770
$1100a
$890
a. This control measure is proposed for the control of other types of emissions in addition to NOX.
3-36
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TABLE 3-8. INVENTORY OF HYDROCARBON EMISSIONS UNDER THE
EPA OXIDANT IMPLEMENTATION PLAN*, FOUR COUNTY AREA
Source
Category
Petroleum Industry
Stationary Fuel Combustion
Minerals Industry
Aircraft Operations
Motor Vehicles
Organic Solvents
Metallurgical Processes
Chemical Industry
Other
TOTALS
Emissions When Plan is
Implemented
1972 1977
67.1 17.3
1980
18.2
--
15.7 26.7
961 472
43.0 30.4
37.1
325
30.0
.7 .8
1095 547
.8
410
*The EPA oxidant plan consists of the following control measures:
t Vapor recovery systems for gasoline marketing operations.
Inspection/maintenance and catalytic converter retrofit
for motor vehicles.
c Restrictions on the use of organic solvents and on
emissions from organic solvent operations.
3-37
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Conversion to synthetic, clean-burning fuels is another possible air pol-
lution control option in which new technology must be consolidated into
commerical production systems. Various studies have demonstrated the
adaptability of current fuel systems to methanol fuel, and confirmed its
effectiveness in reducing polluting emissions from fuel burning operations.
Construction of several large methanol producing plants is now being con-
sidered as an economic route to fuel supply needed by the electric utilities.
S$2 cleanup systems represent an established emission control technology,
but one which has been employed in a limited number of applications. Still
there are several SOp removal systems commercially available for removal
of S02 gases from stack effluents. In each of these systems the objective
is to produce a sulfur product (elemental sulfur, sulfuric acid, or sul-
fates) which may be removed mechanically from the system.
The most promising equipment which has been developed to be responsive
to the problem of sulfate emissions from vehicles equipped with catalytic
exhaust control devices is an SOp scrubber-muffler system. The unit
operates on the basis that lead and sulfur will react with an alkaline
molten carbonate placed in the scrubber. The unit also is highly effective
for collection of total particulates. Limited testing has been performed
with the scrubber-muffler device, and there are no immediate plans by its
manufacturer to commit the concept to a production effort.
The other significant emission control options identified in the study
include the standard air pollution control equipment now used extensively
in many emission-control applications. Both baghouses and electrical pre-
cipitators may be incorporated as emission controls in cases where: 1)
sources are currently uncontrolled by either of these two devices, or 2)
when the efficiency of the existing precipitator or baghouse may be improved.
3-38
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In the latter case, improving the collection efficiency may involve the
replacement of an older, or less efficient unit, or the retrofit of an
existing unit with additional equipment.
Control options classified as administrative policy were not addressed
except very briefly, in this study. The implementation of shutdowns, par-
tial or total, or relocation of process categories to locations where their
generation of pollution is tolerable, is generally unfeasible from an
economic standpoint. The actual disruption and socio-economic impact of
this control option was not assessed quantitatively. It was assumed this
approach would be considered as a last resort only, or possible as an op-
tion allowed the manufacturer in lieu of compliance with local emission
regulations.
The cost effectiveness figures of Tables 3-5, 3-6 and 3-7 must be
judged with some reservation. For example, the desulfurization control
option may not be fairly represented by its cost effectiveness as applied
to one source category alone since its implementation in the petroleum in-
dustry would produce reductions in SO^ emissions whenever the associated
petroleum products are used, and these reductions have not been credited
to this control in Tables 3-5, 3-6 and 3-7. If desulfurization was adopted
as a universal emission control method for the petroleum, fuel combustion,
motor vehicle, and aircraft emissions source categories, its overall cost
effectiveness would be markedly improved because of the overlapping control
achieved among the various source categories.
The cost of controlling aircraft particulate emissions is greater than
the control cost for any of the other control options. However it should
be realized that these cost figures may be high, since the emission reduc-
tions attributed to the major combustion chamber redesign and ground
3-39
-------
operation modifications were conservative estimates, calculated to a base-
line turbine engine which emits at "best emission rate" levels.
Obviously, the cost effectiveness of a given control option will vary
accordingly to the degree of pollution which is available for cleanup. For
example, S02 removal systems are shown to cost $101 per ton of S02 removed
when installed to manage emissions of metallurgical furnaces, but cost
$1540 per ton of SO^ removed when treating effluent gases from stationary
fuel combustion units. The difference in cost effectiveness is due in large
part to the more concentrated emissions of SO,, which are available for con-
trol from lead melting furnace effluents.
In general, the cost effectiveness of the various controls for the mo-
bile emission sources appears least impressive. These controls involve the
incorporation of retrofit technology to individual engines. Traditionally
this type of control has been more expensive than those which are associated
with stationary industrial process operations. The source emissions from
the individual engines are relatively small, and there is therefore only
minimal control potential available.
Within each process category there are unique air pollution problems
/
which lend to treatment by the various alternative control measures in
distinctly separate ways. Tables 3-5, 3-6 and 3-7 show that each of the
significant control measures identified in the study is the most effective
control approach available for at least one of the major source categories.
In some cases, there are only minor advantages to be gained in emission
control by using one control in preference to another. For example, de-
sulfurization of petroleum products to very low sulfur content can result
in effective emission control for S02 emissions from motor vehicle travel,
3-40
-------
fuel combustion, and petroleum refining operations. Slightly greater SCL
control can be achieved for the former categories by utilizing other op-
tions, since they provide slightly greater removal efficiency for a given
source (SOp muffler-scrubber for motor vehicles), or they enable control
of a larger portion of the sources within the process category (S02 clean-
up systems can effect emissions from refinery heaters as well as from
boilers).
Clearly there are a great number of factors which must be examined
to determine which of the emission control options may be the "most ef-
fective." First it is evident that emission controls for the four largest
source categories cannot be evaluated on a mutually exclusive basis. If
a single control method can be utilized throughout the source categories,
its effectiveness would have to be judged according to its overall benefits,
as well as the singular effects on each process category. Another factor
in the fair appraisal of the candidate emission control methods involves
technical feasibility. Some of the measures are in a higher state of
technical refinement than others, and may therefore be more feasible in
terms of immediate implementability. Another consideration in candidate
appraisals must be the long-term potential it possesses for meeting emis-
sion standards which become increasingly more stringent with time. Several
other factors are significant in the true appraisal of an emission pre-
vention system. Identification of these factors, and their relative sig-
nificance, is developed in the final control strategy formulation of the
succeeding section of this report.
The following discussion (Sections 3.2.1 to 3.2.9) provides a brief
narrative for the control options for each of the source categories. It
3-41
-------
includes a characterization of: 1) atmospheric emissions arising from the
source category, 2) the prevailing emission control technology presently
being utilized and 3) the control options and their impact on emissions.
3.2.1 Petroleum Industry
Emissions^
The greatest quantity of air contaminants from the petroleum industry
originates from refinery operations. The quantities of these emissions
generated from refineries in the Four County Area are given in Table 3-9.
Regeneration of the Catalyst utilized in the catalytic cracking of petro-
leum produces the largest portion of particulate, S02, and NOX emissions
TABLE 3-9. EMISSIONS OF PARTICULATES, S02, AND NOX FROM REFINERY .
OPERATIONS, FOUR-COUNTY AREA, 1972
Process Emissions to Atmosphere % Particulate Emissions
Ton/Day in This Industry
PARTICULATES
Petroleum Coke .7 22.4
Operations
Catalytic Cracking 2.2 73.2
Other .1 4.4
TOTAL 3.0
so2
Catalytic Cracking 57.2 95.4
Other ^ 2.8 4.6
TOTAL 60.0
NOX
Catalytic Cracking 60.5 89.8
Other 7.0 10.3
TOTAL 67.5
Source: Support Document #4,[4].
3-42
-------
from this industry.
Existing Controls
Table 3-10 lists the type of control equipment currently being utilized
to reduce particulate emissions of petroleum refining emission sources.
It has been estimated by the Los Angeles APCD that over 90% of refinery
particulate emissions are prevented from entering the atmosphere.
TABLE 3-10. CHARACTERIZATION OF CONTROL METHODS-CURRENTLY UTILIZED
IN PETROLEUM INDUSTRY FOR CONTROL OF MAJOR PARTICULATE
EMISSION SOURCES, FOUR-COUNTY AREA, 1972
Actual Emissions Average
Process Operation lb/daya Control Efficiency
Petroleum Coke - 102Q None(except for
Conveying wet treatment)
15 Baghouse 89.6
Size Reduction 14 Baghouse 94.7
Storage 381 None
Catalytic Cracking 4400 Electrical 95.0
Precipitation
aFigures are based on Reference [58], adjusted to reflect the overall
Four-County emission totals as reported in Support Document #2,[2].
The traditional air pollution control devices, electrical precipita-
tors, fabric filters, mechanical collectors, and wet scrubbers are used
throughout the petroleum industry to control particulate emissions from
large sources and a variety of small pollution generating sources. This
equipment is suitable for reducing most emissions to negligible levels.
However, despite levels of control which are in the neighborhood of 95% re-
moval efficiency, the volumes of gases (up to 150,000 cfm) vented from a
3-43
-------
large regenerator still carry substantial emissions approaching the 30
Ib/hr maximum (Rule #54, Solid Particulate Matter).
The major S09 and NO emissions of the petroleum industry result from
£ f\
catalytic regeneration operations, and are uncontrolled at present. There
are currently no scheduled preventions planned for these sources.
Additional Control Options
Alternative controls which may be applied to refinery operations to
reduce particulate and gaseous precursors emissions consist of both add-on
equipment and process alterations.
Control of Particulate Emissions:
Retrofits to precipitators for improved performance is
generally possible with newer equipment, but because of the rapid
evolution of technology in the air pollution control industry,
older generations of precipitators cannot be practically retro-
fitted. An additional problem in the retrofitting of existing
precipitators is the space limitation constraining the retrofit.
Typically most manufacturers have utilized all available space
in the initial control equipment installation, such that retrofits
may be extremely costly and probably less desirable than replace-
ment alternatives.
Due to a history of stringent air pollution controls in the
Los Angeles Area, all local refineries have operated air pollution
control equipment for several years. Most of this equipment has
been updated in the last 3 to 5 years to reflect increasingly
stringent emission regulations. Thus some of the equipment may be
retrofitable to meet further demands for air pollution prevention,
but it is likely that a large portion of the existing equipment would
require replacement,due either to the economical or physical unfeasi-
bility of configuration changes, or to the unavailability of adaptable
retrofits on previous generation equipment.
3-44
-------
The impact of equipping the refineries in the Los Angeles
area with higher performance (99% removal) participate emission
control equipment is outlined in Table 3-5. The measure would
provide for a 1.8 ton per day reduction in particulate emissions
from refineries in 1977. The annual cost of the control is esti-
mated at .25 million per year, or $512 per ton of particulates re-
moved.
Control of Gaseous Precursors:
There are many commercial methods for SCL removal from ef-
fluent gas streams, but to date relatively few of these have been
thoroughly tested. Hence the operating and performance data asso-
ciated with these recovery systems is very limited. Since refinery
operations are not the primary contributor to SCL air pollution,
none of the pilot S02 removal installations are directed at the re-
moval of SCL from refinery regenerators. Most of the applications
of commercial systems are now being used to recover sulfur from
power plant stacks and sulfur recovery plant tail gases. However,
a number of the SCL removal systems now being commercially pro-
moted are applicable to a variety of flue gases containing SCL.
Particularly adaptable to a wide range of effluent gases are wet
scrubbing techniques, such as the Wellman Lord process, the Double
Alkali-system and the lime-scrubber technique.
The Wellman-Lord SCL removal system may be particularly well
suited to application in refineries since its process produces a
concentrated SOU gas, which can be delivered to sulfur recovery
plants already existing at the refineries. While the quantity of
sulfur which can be recovered from regenerator flue gases is not of
appreciable magnitude to generate important economic benefits, the
employment of the sulfur recovery using the Wellman-Lord principle
avoids some of the supply and waste discard problems inherent in
the wet scrubbing techniques. The Wellman-Lord process is now
being utilized in 10 systems of different magnitude throughout the
United States, and presently, 12 other systems are in construction.
The manufacturer, Davy Power Gas Company, can guarantee an effluent
3-45
-------
S02 concentration of less than 100 ppm. Obtaining this level of
emissions would correspond to a 90% S02 emission reduction from
the regenerator effluent stream.
Several other S02 removal systems may also be applied to the
regenerator flue gases. A number of these may be able to remove
over 90% of the S02, although their performance under the condi-
tions of this application is unproven. These systems, notably the
wet absorption methods, have been discussed in Support Document #4.[4],
The impact of add-on S02 removal systems to cracker units at
the refineries in Los Angeles is given in Table 3-6. A 90% removal
of S0? in the stack gases was assumed, providng a 51.4 ton per day
reduction in S02 emissions from refinery emissions in 1977. The
annual cost of these controls is estimated to be $3.8 million per
year, or $193 per ton of S02 removed.
Another approach to the control of S02 emissions from refinery
effluent streams is the desulfurization of those petroleum distil-
lates targeted for catalytic cracking. The desulfurization of all
those petroleum fractions fed to the catalytic cracker unit cannot
be achieved with existing desulfurization equipment. The Chevron
VGO Isomax Desulfurization Process is suitable for the desulfuriza-
tion of catalytic cracker feed stock. Sufficient sulfur removal
may be achieved to produce low sulfur products from the cracker and
to reduce the sulfur oxides content in the regenerator stack gas to
appreciably lower levels.
Construction of new desulfurization facilities with the capa-
bility of throughputting current cracker feed volumes and proces-
sing the feed to .05% sulfur will be required if refinery S0? emis-
sions are to be reduced substantially by this route. The expected
emission reductions from these facilities would amount to a pre-
vention of 51.4 tons per day of S02 emitted to the atmosphere
(Table 3-6). The cost of construction, operation, and maintenance
of the desulfurization facilities would amount to an annual cost of
$19 million, or a cost of $964 for each ton of S02 prevention.
3-46
-------
3.2.2 Stationary Fuel Combustion
Emissions
The most significant emissions arising from stationary fuel combustion
are sulfur dioxide gases. Combustion sources presently account for about
46% of all atmospheric SOp, 21% of the particulate emissions, and 20% of
the NO . These emissions are distributed throughout the Four County Area.
A
Emission rates vary among the various types of stationary combustion
equipment. The emissions are dependent on type and size of equipment, the
method of firing, and the degree of maintenance. Table 3-11 provides a
summary of various types of fuel burning equipment found in the South
Coast Air Basin. The smaller units (domestic and commercial) burn entirely
on a schedule of natural gas and the larger industrial units burn either
natural gas or fuel oil. Many industrial units are equipped for fuel con-
version, and still others are able to burn both natural gas and fuel oil
simultaneously.
TABLE 3-11. SUMMARY OF FUEL BURNING EQUIPMENT
Equipment Category Description
Power Plants Power plant boilers
Industrial Large and medium sized boilers, refinery
heaters, stationary internal combustion
engines
Domestic & Commercial ' Residential, combustion (space heaters,
water heaters, ranges), and small
commercial boilers.
The effect of fuel type on emissions from combustion units of power
generating stations is illustrated in Table 3-12. Emission rates of both
nitrogen oxides and particulate matter are substantially higher when burn-
ing fuel oil than when burning natural gas. There are essentially no
3-47
-------
emissions of sulfur dioxide when natural gas is burned.
TABLE 3-12. POLLUTANT EMISSIONS BY FUEL TYPE FOR BASIC
COMBUSTION CATEGORIES IN FOUR-COUNTY AREA
Year
Pollutant
1972
1977
1980
Parti culates
SO?
NOX
Parti culates
S02
NOX
Parti culates
S02
NOX
Power
Nat. (las | ui
1.5
1.1
44.0
.1
.2
6.2
.1
.2
7.6
i
20.
179
49.
35.
292
129
36.
304
135
Plant
T~
8
5
9
7
r Tota
1
22.
180
93.
36.
292
135
36.
304
143
1
3
3
0
8
Industrial
Nat. Gas | Oil
6.6
.3
26.4
3.7
.2
31.0
4.5
.2
37.0
5.5
27.3
88.4
32.2
81.0
445
28.0
85.0
388
I Total
12.0
27.6
114.8
35.9
81.2
476
32.5
75.2
425
Domestic
Nat
.Gas
10
74
11
61
12
61
.6
.3
.1
.6
.4
.1
.3
.4
.1
Source: Reference [2].
Existing Controls
Applied emission control technology for combustion units includes:
1) fuel modification, 2) burner design and operation techniques, and 3)
removal of pollutants from stack gases. The effectiveness of fuel modi-
fication for pollution control has been illustrated in Table 3-12. This
pollution control approach is used whenever the supply of natural gas per-
mits. However the effectiveness of this approach will be limited in future
years due to the smaller quantities of fuel gas available.
Stack treatment for removal of pollutants from combustion systems has
not been employed in the Four-County Area. In the past, emission regula-
tions have been met through the use of clean fuels and burner adjustments.
Projected regulations are not expected to provoke any changes in this
status.
Reduction of NOX in existing boilers large enough to be under
3-48
-------
jurisdiction of Rule 68 (Fuel Burning Equipment) has been accomplished by
operations changes or combustion modifications. These control methods are
applicable to smaller burner units' but are not required under present
regulations. Rule 68 limits NO emissions to low levels (325 ppm stack
/\
gas concentration) and is targeted for larger boilers at the power plants.
Control methods utilized by Edison Company in complying with Rule 68
include: 1) off stoichiometric diffusion flame operation, 2) two-
stage combustion, and 3) flue gas recirculation (these methods are
discussed in the next section). The overall reduction of NO emis-
/\
sions due to these controls from all units tested at Edison Plants was
over 50 percent,[59].
Additional Control Options
The technology available to reduce emissions discharged by fuel com-
bustion consists of equipment modification and operational changes, flue
gas treatment, and fuel substitution. Except for fuel substitution, no
single control method is effective in preventing emissions of all pollu-
tant species (particulates, S02, NOX).
Control of Particulates
With conventional use of burner equipment, particles in the
flue gases can generally be maintained well below the emission
standard of .3 grain per scf of exhaust (Rule 53b). Given proper
operation of the combustion burners, the rate of particulate emis-
sions depends primarily on fuel type. The efficient burning of a
common heavy residual oil of .1% ash results in a stack gas con-
centration of only .03 grain per scf. There is no measurable in-
organic ash in exhaust gases from the combustion of natural gas.
Low sulfur oil contains small amounts of ash. Hence, the exhaust
gases of typical fuel burning is not likely to exceed local
standards.
3-49
-------
While the relative emission rate of participates from fuel
combustion is low, the immense volumes of exhaust gases produced
by large oil burning units result in appreciable discharges of
particulate matter to the atmosphere. Because of the large vol-
umes of exhaust and the small size of particulates in the gas
stream, only the electrical precipitation and fabric filter are
suitable candidate controls for this application.
A removal efficiency of 99.9% is typically obtained with a
fabric filter for particles 1n the submicron range. By comparison,
electrical precipitators which collect submicron size particles at
over 95% efficiency require additional equipment at greatly in-
creased costs. However fabric filters Travelnot.been used ex-
tensively to handle applications in which the gas volumes to be
treated are as large as that emitting from a utility boiler.
Manufacturers of fabric filters state this is because the fabric
filter is not competitive when installed for such immense effluent
volumes.
The impact of equipping oil-burning equipment in the Four
County Area with high efficiency (95% removal) electrical pre-
cipitators, or fabric filter baghouses (99.9% removal) on fuel
burning emissions is shown in Table 3-5. Table 3-13 summarizes
the cost of the two particulate control options for oil-burning
combustion equipment. The electrical precipitator is slightly
more cost effective as a control for larger fuel burning equip-
ment, and equally cost effective to the fabric filter when proces-
sing the smaller effluent volumes associated with boilers of less
thermal rating. Since the baghouse has not been used extensively
to control emissions from large boiler units, it appears that its
selection for this application would be unwarranted. The baghouse
is significantly more cost effective as a collector for refinery
heater emissions, and should probably be recommended for this ap-
plication.
3-50
-------
TABLE 3-13. COST OF PARTICULATE EMISSION CONTROL FOR
OIL-BURNING COMBUSTION EQUIPMENT, 1977
Equipment
Large power plant boilers
(Average size = 260 MW)
Small power plant boilers
(Average size = 65 MW) .
Large non-power plant
boilers (Average size
= 78 MW)
Refinery heaters
(Average size =6.5 MW)
Number
Of
Units
35
II
49
"
152
II
220
u
Control
high efficiency electro-
static precipftator
high efficiency baghouse
high efficiency electro-
static precipitator
high efficiency baghouse
high efficiency electro-
static precipitator
high efficiency baghouse
high efficiency electro-
static precipitator
high efficiency baghouse
Cost
Initial
Purchase &
Installation
Cost x 10°
48.1
38.5
13.5
12.2
68.4
60.8
28.6
28.6
in Millions
Operation
Cost
Increase
7.0
10.5
2.0
2.2
9.1
11.4
3.3
2.1
of Dollars
Annual i zed
Cost
Increase
12.6
15.0
3.6
3.6
17.1
18.5
6.7
5.4
Cost per
Ton of
Parti cul ate
Reduced
$1452
1671
932
904
1530
1590
241 Oe
1863
co
i
en
Source: Reference [4].
-------
NO Control:
y\
The control of NO emissions from combustion units is primarily
X
a function of the control of temperature and residence time in the
primary flai.ie zone. Both of these functions can be managed by
modification of operating conditions and by modification of design
features in existing combustion units. Numerous methods of modify-
ing the operating conditions have proven successful and may be
adopted for use in existing combustion units. These include: l)low
excess air firing, 2) two stage combustion, 3) flue gas recircula-
tion, 4) steam or water injection, and 5) direct temperature con-
trol . Design modifications which may be utilized for NO control
s\
generally involve an alteration in the burner and furnace configu-
ration, or the location and spacing of burners.
The effect of implementing the various NO control alternatives
/\
for combustion units in the Four-County Area is summarized in Table
3-14. The most feasible combinations of NO control options have
J\
been examined. As a single control, low excess air firing was con-
sidered the most appropriate option, due to its cost advantages
over other equally effective options (such as direct temperature
control, or flue gas recirculation). Low excess air firing results,
on the average, in 40% reductions of NO emissions from commercial
A
and industrial boilers. These boilers generally are fired to 15-30%
excess air, and may be reduced to 2-6% according to tests. In
power plant boilers less than 1775 MBTU/HR, excess air firing is
typically 5-15%, and NO reductions from lower excess air firing
/\
averages about 30%. Tests conducted with refinery heater units
have confirmed 40% reductions are attainable ,[60].
To develop additional NO removal, flue gas recirculation may
/\
be used with low excess air firing to achieve NO reductions of 70%
/\
from boilers. The feasibility of utilizing flue gas recirculation
in refinery heaters as a retrofit is not clear at this time. There
is currently evidence which indicates this approach requires de-
velopment of an entire new heater design. Hence, this control option
was not considered for implementation on refinery heaters ,[60].
3-52
-------
TABLE 3-14. THE EFFECT OF NOX EMISSION CONTROLS ON FUEL COMBUSTION EQUIPMENT,
FOUR-COUNTY AREA
CO
I
U)
Co
Un
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Projected NOX
Average Emissions
nbustion size . Tons/Bay
ft Description MBTU/Hr 1977
Large power plant 2630 105
boilers (1825-3550
MBTU/hr)
Small power plant 660 30
boilers (100-1775
MBTU/hr)
Large non-power 80 118
boilers (30-400
MBTU/hr)
Medium sized boilers 9 205
(2-30 MBTU/hr)
Large refinery heaters 120 38
(90-290 MBTU/hr)
Small refinery heaters 45 27
(5-90 MBTU/hr)
Large stationary In- 700 H.P. 69
ternal combustion
engines (>300 H.P.)
Small compressor 200 H.P. 19
engines « 300 H.P.)
Domestic (residential) - 46
fuel combustion (space
S utter heaters, ranges)
Small commercial and - 15
industrial boilers
( 2 MBTU/hr)
1980
111
32
105
183
34
24
61
17
46
15
Control Measure
None-already equipped with advanced
combustion control (emissions are
controlled to about 20% of
uncontrolled emissions level)
Low excess air firing
* flue gas recirculatlon
Low excess air firing
& flue gas recirculation
Low excess air firing
4 flue gas recirculation
Low excess air firing
Low excess air firing
Water Injection or exhaust gas
recirculation
Water Injection or exhaust gas
recirculation
None
None
NO, Reduction In
1977
Percent
30
50
40
70
40
70
40
40
75
75
-
-
Tons/Day
0
9
15
47
83
82
144
15
11
52
14
0
0
Cost/Ton
Of NOX
Reduction
0
$200
450
22
127
694
870
27
226
13
37
-
-
Source: Reference [47].
-------
Many controls have already been applied in power plants to
comply with the NO emission reductions required by Rule No. 68.
/\
These control options are applicable to large utility boilers and
have not been considered as candidate alternatives in Table 3-14.
The compact size and limited number of burners in other boilers
and in heaters render these options technically unretrofittable
for applications other than large utility boilers. These alterna-
tives include two stage combustion, relocation of burners, modifica-
tion of burner spacing, and others.
There are currently no retrofit controls developed to manage the
NO emitting from residential fuel combustion, and small industrial
A
and commercial boilers. New units may be designed to control NO
A
emissions, but because retrofit controls would require relatively
extreme costs for these small units, they would probably not be
politically acceptable. Hence, no controls have been considered in
Table 3-14 for these smaller source categories»[61].
Stationary internal combustion engines (used primarily in gas
and oil industry for gas compression) can be retrofitted with water
injection or exhaust gas recirculation equipment to obtain NO emis-
A
sion reductions of about 75%. The two approaches are equally cost
effective. Stochiometric fuel adjustments have been shown effective
in reducing NO emissions to 70%, but the associated loss in power
/\
and fuel economy make this control method less desirable than water
injection or exhaust gas recirculation,[60],[62],[63].
The cost effectiveness of the various NO control options for
A
combustion units in the Four-County Area is summarized in Table 3-14.
The least costly control alternative consists of either water injec-
tion or exhaust gas recirculation, applied to stationary internal
combustion engines. This measure may be incorporated on large en-
gines at a cost of only $13 per ton of NO emissions prevented. The
A
most costly NO control option is also the most significant in terms
X
of overall NO emissions, low excess air firing and flue gas recir-
A
culation in medium sized boilers. The cost for this retrofit is
$870 per ton of NOV removed.
3-54
-------
Control of SCy
An obvious means of reducing emissions of S0? from fuel com-
bustion is to remove the sulfur from the fuel. Present regulations
permit .5% sulfur content in fuel oil (Rule 62). This standard was
initially adopted with the intention of motivating utility companies
to substitute natural gas for fuel oil. At the time the regulation
became law, natural gas was more abundant.and less expensive than
the low sulfur (.5%S) fuel oil. Hence,the desired switch to gas
use occurred quickly and emissions from power plants decreased ap-
preciably. These gains in air pollution control have diminished in
recent years and are expected to be realized even less because of
the continuing shortage of natural gas, and the increased burning
of low sulfur fuel oils.
Currently, low sulfur fuel oils of .5% sulfur content are
typically produced by: 1 )desulfurization of heavy distillate to
produce very low sulfur blend stocks, and 2) blending these low
sulfur stocks with the high sulfur residuum portion of the barrel.
Low sulfur processing of the residuum has not been practiced ex-
tensively, and it is becoming evident that this will be required if
petroleum products are to be manufactured according to the increas-
ingly stringent standards. Several processing schemes are being
proposed as possible routes to very low sulfur fuel oils. Two of
the most feasible methods were discussed in Section 3.1. These
methods have been tested in pilot development and are termed: 1)VGO
Isomax Plus Solvent Deasphalting, and 2) VGO Isomax Plus VRDS Isomax.
Both of these processes lend to stepwise construction at the refin-
ery and are integrateable with existing refinery equipment. The
level of sulfur content obtained by these processes is .05%.
Another obvious means of controlling S02 emissions is incorporation
of S02 removal systems in the stacks.'
Several SCU cleanup processes are commercially available to
manage emissions from fuel-burning combustion unit stacks. These
methods are discussed in Section 3.1. Several installations are
now operating at various power plants throughout the nation to con-
trol SCL emissions within new and more stringent state pollution
3-55
-------
standards. Many of the SO^ removal processes are being tested under
pilot projects (mainly utility boiler stacks) sponsored by the EPA
Comparative evaluations of the various S02 cleanup processes is
not possible since many problems still remain to be identified dur-
ing development and commercial operation. It seems certain, however,
that a number of processes will be available to provide guaranteed
reductions of 90% for a variety of applications>[64].
The effect of implementing the potential SOp control methods on
fuel combustion emissions throughout the Four-County Area is shown
in Table 3-6. Both .the option of add-on S02 removal system and de-
sulfurization of fuel oil offer the same emission control effective-
ness in the long term. However, desulfurization of fuel oils is not
expected to affect emissions from refinery heaters, since these units
operate primarily on refinery make gas and fuel oil. These fuels
are generally heavy residual oils and high sulfur content gas
streams. They are not practically marketed or further processed,
and are therefore burned in the heating equipment as an economical
expedient. Unless these refinery by-product gases and oils can be
disposed of alternately, it does not appear feasible that low sul-
fur supply stock could be used in its place. Hence, only flue gas
cleanup systems were considered a candidate control for refinery
heater emissions.
Implementation of either control (desulfurization or stack SC^
removal) would result in substantial preventions of S02 entering
the atmosphere. The option of fuel oil desulfurization cannot be
implemented totally by 1977 due to lead time required to construct
the processing facilities. However, by 1980, this option can be
fully implemented.
Desulfurization of fuels to low sulfur levels created beneficial
side effects as the ash content is reduced concurrently with sulfur
removal. Consequently, particulate emissions are reduced when low
sulfur fuels are burned. Particulate emissions originate from un-
burned hydrocarbons as well as the inorganic ash contained in the
fuel, but when combustion conditions are adjusted properly, the ash
3-56
-------
content is the main factor causing participate emissions. Most of
the materials found in stack emissions consist of metal oxides,
sulfates, and chlorides, all of which are directly attributable to
the sulfur and ash content of the fuel. Therefore it may be ex-
pected that the combustion of very low sulfur fuel oil from new de-
sulfurization facilities will result in appreciable particulate
emission reductions. These reductions have been estimated in Table
3-6 (based on source measurement data of the Los Angeles APCD»[65],
and fuel analysis data of residual fuels used in Los Angeles,[66]). It
was estimated that a 40% reduction in particulate emissions may be
obtained when burning the higher quality very low sulfur fuels manu-
factured by the new refinery equipment. These fuels will contain
a negligible quantity of ash ,[67].
The cost effectiveness of implementing the candidate SOp controls
is shown in Table 3-6. Desulfurization of fuel oils is the most
cost effective alternative at $1040 per ton of S02 emissions pre-
vented. This is about 35% less than the cost of adding stack S02
removal processes to all oil burning combustion units in the Four-
County Area. However, desulfurization of fuel oils itself does not
obtain the same total prevention as overall stack control since it
is not applicable to refinery heaters (in which refinery make gases
are disposed of). Hence, stack SO,, add-on control must be used with
fuel desulfurization to obtain 90% prevention of SO* emissions.
Fuel Substitution - A Control for Particulates, S02 and NOX:
The impact of converting to methyl-fuel in fuel burning units in
the Four-County Area is shown in Table 3-15. The effect is dramatic
as the alternate fuel burns virtually pollution free, except for
small amounts of NO .
/\
The cost evaluation shown in Table 3-5,3-6 and 3-7 can be con-
sidered preliminary. It does not include consideration of adap-
tions which will be required for fuel burning equipment when con-
verting from fuel oil to methyl-fuel (equipment such as fuel pumps
and nozzles will require modification). However, most of these
adaptions are not expected to incur substantial expense, and have
therefore been neglected in prior cost estimates.
3-57
-------
TABLE 3-15. IMPACT OF CONVERSION TO METHYL-FUEL IN
COMBUSTION UNITS IN FOUR-COUNTY AREA
Emissions expected in 1980
from combustion with burn-
ing fuel oil
Emission reductions when
methyl -fuel is used as
fuel, 1980
Parti culates
65
65
so2
379
379
N0x
431
*
328
*
Based on emission rate of 1000 Ibs/NOj, per 1000
equivalent barrels of natural gas, and projected fuel re
requirement of 111 x 106 barrels fuel oil in 1980,[52],
[53],[68].
The preliminary data demonstrate clearly that methyl-fuel should
be given serious consideration as: l)a clean burning fuel which
would solve many air pollution problems, and 2) an economical fuel
substitute which can be manufactured from domestic raw materials,
without dependence on foreign petroleum stocks. The lead time to
build a methyl-fuel producing plant, 3-4 years, would pose serious
difficulties in imposing fuel substitution plans in the near term.
In addition, the political and social disruptions resulting from
an enforced imposition of fuel substitution would make a near term
conversion unfeasible.
3.2.3 Minerals Industry
Emissions
Most of'the emissions arising from the mineral industry in the
Four-County Area are from twelve basic process categories. These are
aggregate operations, abrasive blasting, clay and clay related operations,
cement operations, asphalt saturation, glass and frit operations, concrete
batching, sand handling, asphalt batching, foundry sand operations, cata-
lyst production, and lime and limestone operations. Emissions are general-
ly in the form of dust from screening, crushing, storage, and handling
3-58
-------
operations, where the material being handled is dry. Those emissions which
are most difficult to control are those emitted from processes such as
quarrying, yard storage and transportation.
12.3 tons/day of particulate emissions come from mineral operations
in the Four-County Area (see Table 3-5). This amount is 6% of the total
particulate emissions from all emission source types in this area.
NO and S09 emissions from mineral operations are negligible in the Four-
X £
County Area.
Existing Controls
Table 3-16 shows a summary of emission controls for each of the twelve
major mineral operation categories. In the table, each emission control
method as it is applied to each category is listed. The range of efficiency
and average efficiency is shown for each control method along with the
amount of particulates emissions for each category that comes from sources
which are controlled by each method. It can be seen that the most frequent-
ly applied control devices in the mineral industry are the fabric filter and
mechanical collector. The use of high efficiency particulate control de-
vices have been used whenever economically feasible to control emissions at
the larger point sources. Because the industry typically handles immense
process volumes, the preventions accomplished by the emission control equip-
ment has been substantial - over 100 tons per day.
According to the APCD emissions file, many mineral operations are un-
controlled. The data of Table 3-16 indicates that a total of approximately
four tons per day of particulate matter is emitted from uncontrolled mineral
operations. However, it has been found through further investigations that
many of these so called uncontrolled sources are, in fact, controlled.
Many operations involving aggregates, clay products, cement, concrete and
3-59
-------
TABLE 6--2. SUMMARY OF EMISSION CONTROLS CURRENTLY UTILIZED
IN MINERALS INDUSTRY OF LOS ANGELES COUNTY
1.
2.
3.
4.
5.
6.
7.
i
Process
Aggregate
Operations
Abrasive Blasting
Clay and Clay
Related Operations
Cement Operations
Asphalt Saturation
Glass and Frit
Operations
Concrete Batching
Parti culates
Efficiency of
Control
Dry Filter, Baghouse
Dry Filter, Other
Dry Inertlal
Separator
Dust Suppression
System
Scrubber
None
Dry Filter, Baghouse
Dry Filter , Other
Separator
Scrubber
M1st Collector
None
Dry Filter, Baghouse
Dry Inertlal
Separator
Scrubber
None
Dry Filter, Baghouse
Dry Filter, Other
None
Dry Filter, Other
Electrical
Pred pita tor
Mist Collector
Scrubber
None
Dry Filter, Baghouse
Spray Booth Ceramic
Dry Inertlal
Separator
Scrubber
None
Dry Filter, Baghouse
Dry Filter, Other
Scrubber
Control
Range Average
0
50-99
.-90-95
90-93
20-95
0
98
99
97
98
0
90-99
98
0-80
0
90-99
0-99
0
97
93
89
75
0
87-99
0
93
0-87
0
96
0
50
Dust Suppression System 98
8.'
Sand Handling
None
Dry Filter, Baghouse
0
99
Dry Inertlal Separator 83
9.
10.
11:
..
12J
.
'.
>.
Asphalt Batching
Foundry Sand
Operations
Catalyst
Production
Lime Limestone
Operations
Totals
Scrubber
Dry Filter, Baghouse
Scrubber
None
Dry Filter, Baghouse
Scrubber
None
CO Boiler Cyclone
Dry Filter, Baghouse
Scrubber
Incineration, Direct
Flame
None
Dry Filter, Baghouse
Scrubber
78
99+
99+
0
93-98
79-89
0
0
99-99+
81
98
0
80-99
98
0
98
94
93
52
0
98
99
98
0
97
98
80
0
99
69
0
97
93
89
75
0
96
0
93
85
0
96
0
50
98
0
99
83
78
99+
99+
0
97
88
0
0
99
81
98
0
98
98
Lbs/Day
Emitted
4472
179
60
566
686
104
5.2
4701
33
971
601
21
165
238
1430
9
244
249
493
204
207
804
159
30
62
221
522
195
2
69
276
269
529
9
116
143
635
509
58
102
13
20
7
579
V
94
351
124
21667
' -r
Lbs/Oay .
Preven- .
tlon '
8771
29
940
7520
743
Q
255
465400
2793
841
1617
0
19432
1029
660
0
141570
20
0
8051 '
6550
1651
621
0
3816
0
824
1252
0
4680
0 "
69 .
13524 v
0
52371
44
411
14160
62865
0
1875 .
748
0
0
693
2468
2303
0
17199
6076
853871
Notes:
l.« Where control Is designated as "none" It Is probable that wetting
techniques are being utilized to reduce dust emissions (see text).
Source: Reference [92].
3-60
-------
sand are conducted while the material is wet or damp. Wetting the material
suppresses dust emissions, and is an effective and economical control
not identified in the available data.
Additional Control Options
The vast majority of significant particulate emission sources of the
mineral industry are controlled by standard collector devices. Improving
emission control in this industry would necessarily involve the employment
of additional devices (such as baghouses, scrubbers, and cyclones) at the
numerous "uncontrolled" process transfer points. Currently, dust emissions
from various transfer operations are minimized by insuring all materials
are wetted as they are processed from one operation to another. Of the
four tons per day of particulates arising from the numerous uncontrolled
point sources, it is probable that nearly all of it could be collected with
additional control equipment installations. However, it is clear that such
an installation program would involve severe economic penalties.
It is significant that wetting practices have proven effective in re-
ducing dust emissions to levels complying with APCD regulations. The emis-
sions are not visible (meeting with Ringleman Rule No. 50), do not pose a
nuisance (Rule 51), do not exceed the maximum permissible concentration
(Rule 52), and do not violate the process weight rule (Rule 54). If any
source has, in the past, violated any of these regulations, it has since
been equipped with additional particulate emission controls or been given
a variance. Hence the controls which are being applied at present have for
the most part been applied according to the present concept of particulate
emission control and the associated technology.
3-61
-------
While economically 1t appears clear that more stringent controls can-
not be feasibly imposed on the mineral industry, there are in addition, in-
herent limitations in the emission inventory which, make untenable the pro-
posal for increased control expenditures. The quantification of particulate
emissions generated by various points in a mineral processing system is
extremely difficult, if not impossible. The "average" emission rates used
in the inventory tabulation are presumed to reflect varied process condi-
tions and configurations which in many cases have never been investigated
empirically or theoretically, and which in many cases, have been modified
significantly since the initial analysis.
It appears that if improvements can be made to the level of existing
controls, they should be directed toward good practice, proper operation,
and maintenance of control efficiency. Control equipment should be care-
fully inspected prior to initial installation and after regular maintenance
to insure that no production faults have occurred, and that adequate control
efficiency is being attained.
3.2.4 Aircraft Operations
Aircraft Emissions
The most significant type of emissions deriving from aircraft operations
are particulates. Figure 3-4 shows that particulate emissions from air-
craft accounted for 7% of the :total particulate emissions discharged to the
atmosphere of the Four-County Area in 1972, and are expected to account for
15% of the particulate discharges by 1980. Aircraft operations accounted
for a small portion of the gaseous particulate precursors emitted in 1972,
but are expected to exercise a more significant role in this type of pol-
lution by 1980.
The magnitude of atmospheric pollution arising from piston aircraft
3-62
-------
20-r
Percentage
of total
atmospheric
emissions
by aircraft
1980
10-
1980
PARtlCULATE
NOX
RHC
Figure 3-4. Role of Aircraft Emissions in Atmospheric
Pollution of Four-County Area.
and jet aircraft in the Four-County Area is shown in Table 3-17. Emissions
from both piston and jet powered aircraft are expected to increase in future
years, owing to the imminent growth rates of these motive types and the
limited pollution control currently scheduled for implementation. Due to
the increasing predominance of jet powered aircraft operations at the vari-
ous airports, piston aircraft are expected to contribute a lesser percentage
of the anticipated aircraft pollution.
TABLE 3-17. AIRCRAFT EMISSIONS, PRESENT AND PROJECTED,
PISTON AND JET
Year
Engine
Type
Parti culates
so2
NOX
RHC
1972
1972
1977
1977
1980
1980
jet
piston
jet
piston
jet
piston
11.5
3.5
22.2
4.6
32.8
5.5
3.4
.2
6.5
. -
9.6
-
12.4
6.2
23.9
8.3
35.4
10.0
9.9
5.8
19.0
7.7
28.1
9.0
Source: Reference [4].
3-63
-------
Emission Controls
Congressional studies (1969) evolving from the Air Quality Act of
1967 identified visible emissions as the most significant problem associated
with aircraft, and as a result, three airlines voluntarily agreed to retro-
fit the widely-used Pratt and Whitney JT8D engines with smoke combustors
by the end of 1972. The smoke combustor retrofit program was further ex-
tended to include all JT3D engines by 1976. Since air operation activity
at the major airports is predominantly composed of aircraft powered by
either JT3D or JT8D engines, it is estimated that the reduced smoke com-
bustion retrofit substantially affected the quantities of pollutants emit-
ting from aircraft acitvity. Hydrocarbon emissions were the most drastical-
ly affected by this retrofit program, while particulate emissions were
also significantly reduced.
Standards requiring major changes in engine emission characteristics
were promulgated for turbine engines on July 17, 1973. The standards con-
sist basically of the following control categories:
1. Retrofit control of smoke emissions and fuel venting
for in-use turbine engines.
2. Standards in 1979 to reduce emissions for new turbine
and piston engines built in 1979 and after.
3. Standards in 1981 to reflect emission reductions
achievable with new large aircraft engine designs.
Alternative Control Options
The current emission standards will result in substantial emission
reductions only after attrition of pre-1979 engines. Additional controls
i
will be required to bring about significant near-term reductions. Feasible
control technology which may be applied includes:
. Modification of ground operations
« Engine modification (retrofits) for turbine and piston fleets.
3-64
-------
Retrofit Alternatives for Turbine Engines:
The EPA has studied the technology which may be applied to
reduce emissions from turbine aircraft. Engine modification
methods feasible for turbine engines as retrofits are described
briefly in Table 3-18. These modifications can be combined (with
the exception of T4 and T6) to achieve increased emission control
effectiveness.
The estimated effectiveness from these measures are presented
in Table 3-19, in terms of the reductions attainable from the low-
est current emission rates realistically obtainable for the given
turbine engine class. This baseline level is equivalent to the
emissions resulting when an engine is well maintained and operates
with control method tl (smoke combustor). The basis for the effec-
tiveness estimates are document in Support Document #4, [4].
The overall reduction to atmospheric emissions by implementa-
tion of the turbine engine modifications depends on the mix of tur-
bine aircraft classes operating at the various airports throughout
the South Coast Basin. In addition, the overall reductions also
depend on the mix of engine makes within each engine class, and
the degree to which each of these contribute total emissions during
the various segments of the idle-take-off approach cycle. The
engines representative of the turbine engine classes are the JT3D,
JT8D, and JT4A engines. Currently these turbine engines generate
approximately 90% of all polluting emissions from turbine engines.
The importance of the JT9D engine (jumbo aircraft) is expected to
increase in the future emission profile.
Emissions for the different engines vary for the different
modes of operation. Table 3-20 demonstrates that particulate and
SOp emissions from jet aircraft engines are most conspicuous during
the taxi and idle modes. This is due primarily to the fact that
emissions in this mode are sustained over approximately 80% of the
total LTO cycle. Oxides of nitrogen emissisons are most prevalent
during the higher loading conditions of takeoff and climbout. The
distributions are based on actual field measurements performed by
the LAAPCD of aircraft operating at Los Angeles International
3-65
-------
TABLE 3-18.
ENGINE MODIFICATIONS FOR EMISSION CONTROL
FOR EXISTING AND FUTURE TURBINE ENGINES
Control Method
Existing engines
tl - Minor combustion
chamber redesign
t2 - Major combustion
chamber redesign
t3 - Fuel drainage
control
t4 - Divided fuel
supply system
t5 - Water injection
t6 - Modify compressor
air bleed rate
Future engines
t7 - Variable-geometry
combustion chamber
t8 - Staged injection
combustor
Minor modification of combustion chamber
(smoke combustor retrofit) and fuel noz-
zle to achieve best state-of-art emission
performance.
Major modification of combustion chamber
and fuel nozzle incorporating advance fuel
injection concepts (carburetion or pre-
vaporization).
Modify fuel supply system or fuel drainage
system to eliminate release of drained
fuel to environment.
Provide independent fuel supplied to sub-
sets of fuel nozzles to al-low shutdown of
one or more subsets during low-power
operation.
Install water injection system for short
duration use during maximum power (take-
off and climb-out) operation.
Increase air bleed rate from compressor
at low power operation to increase com-
bustor fuel -air ratio.
Use of variable airflow distribution to
provide independent control of combustion
zone fuel-air ratio.
Use of advanced combustor design concept
involving a series of combustion zones
with independently controlled fuel injec-
tion in each zone.
Source: Reference [69].
3-66
-------
TABLE 3-19. EFFECTIVENESS OF ENGINE MODIFICATION IN CONTROL OF
EMISSIONS FROM TURBINE ENGINES, BY OPERATING MODEa
Control
Method
t2b
t2
t2
t2
t3
t3
t3
t4
t4
t4
t4
t4
t4
t5
t5
t5
t6
t6
t6
t6
t6
t6
Engine
Class
Tl
Tl
T2
T3
Tl
T2
T3
Tl
Tl
T2
T2
T3
T3
Tl
T2
T3
Tl
Tl
T2
T2
T3
T3
Pollutant
DP
NOX
DP
NOX
THC
THC
THC
CO
THC
CO
THC
CO
THC
NOX
NQX
NOX
CO
THC
CO
THC
THC
CO
Idle/taxi
0.5
NCC
0.5
NC
NC
NC
NC
0.25
0.25
0.25
0.25
0.25
0.25
NC
NC
NC
0.5
0.5
0.5
0.5
0.5
0.5
Mode
Approach
0.5
NC
0.5
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC
Takeoff
0.5
0.5
0.5
0.5
Qd
fld
fld
NC
NC
NC
NC
NC
NC
0.1
0.1
0.1
NC
NC
NC
NC
NC
NC
Emission rate is fraction of best current rate assumed to be attainable
.through minor combustion chamber redesign and with control method cited.
t2 = Major combustion chamber redesign
t3 = Fuel drainage control
t4 Divided fuel supply system
t5 = Water injection
t6 = Modify compressor air bleed rate
jNC indicates no change
Refers to raw fuel drainage only
Source: Reference [69].
3-67
-------
Airport. It was presumed that these figures could be used to de-
vise representative modal emission distributions.
TABLE 3-20.
MODAL EMISSIONS DISTRIBUTION FOR PRINCIPAL
JET ENGINES IN USE
Percentage of Emissions per LTO
Pollutant
Particulates
so2
NOX
THC
Turbine
Engine
JT3D
JT8D
JT4A
JT9D
FT3D
JT8D
JT4A
JT9D
JT3D
JT8D
JT4A
. JT9D
JT3D
JT8D
JT4A
JT9D
Engine
Class
T2
T2
T2
T3
T2
T2
T2
T3
T2
T2
T2
T3
T2
T2
T2
T3
Idle-Taxi
47
36
70
55
42
39
46
39
12
15
15
9
95
95
90
60
Approach
12
37
11
21
18
28
18
22
14
30
17
15
3.1
3.1
4
18
Takeoff and
Climbout
41
27
18
24
40
33
37
39
74
55
68
76
1.2
1.2
5
22
Calculations for modal distribution are based on
Reference [70] and [71].
3-68
-------
Based on the JT8D and JT3D, the most Widely used engines in the
turbine fleet, the estimated relative effectiveness of the retrofit
controls is as shown in Table 3-21. Actual emission reductions for
the Four-County Area have been calculated from these figures and are
shown in Tables 3-5,3-6 and 3-7.
TABLE 3-21.
IMPACT OF ALTERNATIVE CONTROL ON OVERALL
JET AIRCRAFT EMISSIONS
Control
Method
t2
t3
t4
t5
t6
Percent
Parti cul
50
NC
NC
NC
NC
Reduction in Overall
ates THC
NC
la
71
NC
48
Engine
NOX
A
34
NC
NC
58
NC
Emissions
S0_2
NC
NC
NC
NC
NC
NC = No change
aRefers to reduction due to elimination of raw fuel drainage only,
which constitutes a small portion of emissions in takeoff mode.
New design standard for engines manufactured in 1979 and after
(not a retrofit measure).
Presently, the EPA is proposing that all aircraft engines be
retrofitted to 1979 standards by 1979. The technical feasibility of
this proposal is unclear since alternative retrofits are not in
a good state of refinement at this time,[72]. Few of the control
methods have been developed or applied to aircraft engines. Table
3-22 lists the development time requirements for each of the control
methods. A major consideration in development time consists of the
maintenance facilities and procedures accompanying the retrofitting
equipment. The minimum time for implementation of most of the emis-
sion control methods for turbine engines is estimated to be two and
one-half years.
3-69
-------
TABLE 3-22. TIME AND COSTS FOR MODIFICATION OF CURRENT
CIVIL AVIATION ENGINES
Control Method
Major combustion
chamber redesign
Fuel drainage control
Divided fuel supply
Water injection
Compressor air bleed
Development Development
Time, Years Cost, 106 Dollars
2.5 to 7.5
1 to 2.5
5 to 7.5
2.5 to 4
4 to 6.5
74
1.5
84
25
90
Implementation
Cost, 106 Dollars
665
5.4
102
175
58
Source: Reference [69].
Of the potential methods for aircraft emission control, the re-
trofitting of in-use engines is the most costly. The cost of modify-
ing existing designs for emission control in new engines is approxi-
mately one-half of that incurred by retrofitting. The incorporation
of new control technology during new engine design incurs the least
cost, estimated at a 3-4% increase over the base engine cost. Table
3-23 provides cost estimates for implementing the various retrofit
control methods in the Four-County Area. Implementation includes
initial installation of the control method on all engines of a given
class and the additional effort required for the control method
throughout the remaining life of the engines (assuming 10 year life).
The only measure affecting particulate emissions is the major combus-
tion chamber redesign, which requires; a cost of $4100 per ton of
particulate recovered. NO emissions are reduced most drastically by
A
water injection control, at a cost of $820 per ton of NO controlled.
J^
TABLE 3-23. COST EFFECTIVENESS FOR TURBINE RETROFIT
MEASURES, 1977, FOUR-COUNTY AREA
Cost of Emission Control Per Ton of
Pollutant Prevention
Mpthnd Particulates 2 x THC
Major combustion $4100 - $5770
chamber redesign
Fuel drainage control - - - $17000
Divided fuel supply - - - 550
Water injection - - $820
Compressor jn'r bleed - - - 550
1. Cost of air pollution control benefits are figured for Four-County
Area only, and do hot reflect the tons of emission reductions due
to operation of the aircraft fleet in other areas.
3-70
-------
Modification of Ground Operations:
Aircraft ground operations contribute a substantial portion of
the emissions of particulates, SO., and THC arising from overall
aircraft operations. This is due to relatively high emission rates
of the pollutants at low engine power levels, as well, as the extended
period of operation characteristic of idle-taxi modes for jet powered
aircraft. A number of ground operation modifications have been pro-
posed to reduce taxi-idle mode emissions. Regulations which may
arise from these proposals have been deferred until"operational and
safety considerations can be studied jointly by the EPA and FAAi
The procedures devised to control emissions by reducing the time of
taxi-idle or by operating turbine engines at higher and more ef-
ficient thrust settings are shown in Table 3-24.
Modification of ground operations have been proposed primarily
for reduction of HC and CO emissions. To this end, the most at-
tractive option for ground control is the use of fewer engines at
higher, more efficient power settings during taxi and idle modes.
This conclusion is based on modal emission characteristics of tur-
bine engines, typically protrayed as in Figure 3-5. At the elevated
thrust required when only one engine is used during taxi and idle,
the emission reduction is approximately 80% for HC during this mode.
Since the idle mode accounts for a substantial portion of all tur-
bine engine emissions, the introduction of this ground operation
modification could reduce turbine aircraft hydrocarbon emissions by
approximately 50% (see Table 3-24). However, introduction of the
same ground operation modification will result in increases in par-
ticulate, SOp and NO emissions. Other options for ground operation
controls, such as reducing the amount of time in the taxi and idle
mode, would enable overall reductions in hydrocarbon emissions as
well as particulate and NO emissions. The most effective overall
/\
option in this respect is the towing of aricraft to avoid taxi
emissions.
3-71
-------
IDLE APPROACH
TAKEOFF
0
'50
CO
^40
o
o
o
c
1C
4->
^20
'o
a.
.210
40 60 80 100
Percent thrust
Source: Reference [72],[73].
Figure 3-5. Gaseous Emission Characteristics
of a JT8D1 Turbine Engine
Table 3-24 shows that towing of aircraft to avoid taxi emissions
will reduce particulate and S02 emissions from turbine aircraft to
78% of the levels expected without controls. The projected emission
reductions from the towing measure in the Four-County Area, and
their cost, are shown in Tables 3-5, 3-6 and 3-7. The measure is
most cost effective for preventing emissions of RHC and particulates.
As an overall measure, it provides emission control of all pollutants
for a cost of $79 per ton.
Retrofits for Piston Aircraft:
The EPA has studied the technology which may be applied to re-
duce hydrocarbons and CO emissions from piston aircraft. Control
methods considered feasible for aircraft piston engines include
approaches that have been conceived or developed for automotive
engines. Table 3-25 provides a summary of nine of the piston en-
gine control methods identified by EPA as potentially feasible ap-
proaches. Recent research indicates that control method PI, fuel-
3-72
-------
TABLE 3-24. COMPARATIVE REDUCTIONS RESULTING FROM CONTROL
METHODS APPLIED AT LOS ANGELES INTERNATIONAL
AIRPORT
Resultant Emissions,
% of Baseline Emissions
Control Method Parti culates NOV SO?
1.
2.
3.
4.
5.
6.
Increase engine idle 150 164 150
speed
Increase idle speed
and use minima} engines
for taxi
two engines 134 142 134
single engine 168 186 168
Eliminate delays at 96 99 96
gate and runway
Transport passengers 98 100 98
between terminal and
aircraft
Tow aircraft to avoid 78 91 78
taxi emissions
Avoid use of aircraft 99 100 99
auxiliary power units
(APU)
THC
93
66
51
91
97
42
98.5
Calculations of emission reductions are based on 1) gaseous emission
characteristics of JT8D turbine engine, 2) modal emission distributions,
and 3) hydrocarbon reductions resulting from control methods at Los
Angeles International Airport.
Source: Reference [4].
air ratio control, is the most technically feasible approach to
substantial piston emission reductions. In this approach, leaner
air-fuel ratios are obtained to produce reductions in hydrocarbons
and CO. Figure 3-6 illustrates the effect of air-fuel ratio on
piston emission characteristics. Operation at a 13 to 1 air-fuel
ratio gives more than 50% reduction in CO and HC from levels at a
10 to 1 air-fuel ratio.
3-73
-------
Figure
Source:
9:1 10:1 11:1 12:1 13:1 14:1 15:1
Air-fuel ratio
3-6. Emission Characteristics for Piston Engine
Reference [73].
Because particulate and NO emission rates from piston aircraft
are considered to be relatively low, the EPA has not been directly
concerned with developing controls for these pollutant types. This
is reflected in the aircraft emission standards, which are directed
at control for hydrocarbon, CO and NOX emissions only. Consequently,
the available research data characterizing particulate emissions
during various piston engine operating modes is quite limited-
Although particulate emissions associated with the candidate
piston engine controls have not been specifically determined,it is
expected that those controls which reduce exhaust hydrocarbon emis-
sions will also produce particulate emission reductions. Experience
with reciprocating automotive engines has shown that leaning air i
fuel ratios, currently the leading candidate measure for implementa-
tion as piston engine emission control, effects hydrocarbon emis-
sions.
Currently,there are numerous uncertainties associated with the
technical and economical feasibility of the various control methods
as a retrofit measure. For control Pl.it is suspected that engine
detonation and overheating will occur with leaner air fuel mixtures
in existing engines. Hence a redesign of the cylinder head for
operation at the elevated temperatures would be required, and retro-
fits for measure PI would be economically unfeasible. The FAA is
3-74
-------
TABLE 3-25. ENGINE MODIFICATIONS FOR EMISSION CONTROL
OF EXISTING AND FUTURE PISTON ENGINES
Control Method
Existing engines
pi - Fuel-air ratio
control
p2 - Simple air
injection
p3 - Thermal reactors
p4 - Catalytic reactors
for HC and CO
control
Direct-flame
afterburner
P5
p6 - Water injection
p7 - Positive crankcase
ventilation
p8 - Evaporative
emission controls
Future engines
p9 - Engine redesign
Modification
Limiting rich fuel-air ratios to only those
necessary for operational reliability
Air injected at controlled rate into each
engine exhaust port.
Air injection thermal reactor installed in
place of, or downstream of, exhaust manifold.
Air injection catalytic reactor installed in
exhaust system. Operation with lead-free or
low-lead fuel required.
Thermal reactor with injection of air and
additional fuel installed in exhaust system.
Water injected into intake manifold with
simultaneous reduction in fuel rate to
provide for cooler engine operation at
leaner fuel-air ratios.
Current PCV system used with automotive engines
applied to aircraft engines. Effective only
in combination with one of preceding control
methods.
A group of control methods used singly or in
combination to reduce evaporative losses from
the fuel system. Control methods commonly
include charcoal absorbers and vapor traps in
combination with relatively complex valving
and fuel flow systems.
Coordinated redesign of combustion chamber
geometry, compression ratio, fuel distribution
system, spark and valve timing, fuel-air ratio,
and cylinder wall temperature to minimize
emissions while maintaining operational
reliability.
3-75
-------
currently funding research by piston engine manufacturers
(Continental/Lycoming) to study the feasibility of retrofitting
piston engines for lower emissions with timing and fuel mixture
ratio modifications. However, because of the apparent difficulties
associated with the implementation of this measure, and because
of its potential impact on aircraft emission reductions would be
minor, it has not been included as a candidate control measure in
the study.
3.2.5 Motor Vehicles
Emissions and Present Emissions Control
TABLE 3-26. ROLE OF MOTOR VEHICLE EMISSIONS IN ATMOSPHERIC
POLLUTION OF FOUR-COUNTY AREA
Percentage of Total Emissions in Four-Countv Area
Year
1972
1977
1980
Parti culates
49
35
34
so2
13
11
10
NOX
74
51
46
Reactive
Hydrocarbons
89
85
78
The important role of the motor vehicle in atmospheric pollution in
The South Coast Four-County region is illustrated clearly above. With the
Federal promulgation of air program implementation plans for the State of
California, hydrocarbon and NO emissions from motor vehicles are expected
J\
to decline rapidly in the next few years. While the implementation programs
do not address emissions of particulates and S02 directly, both these pol-
lutant species will be affected by the control measure targeted for hydro-
carbon and NO emission reductions. S09 emissions from light-duty vehicles
j\ £
will be reduced by about 7%, and light-duty vehicle and particulate emissions
by 37%, by the year 1980. The measures principally responsible for these
emission reductions will be non-leaded fuel utilization, in combination
3-76
-------
with the use of catalytic converter exhaust control devices. These measures
are to be required under a retrofit program for all gasoline-powered, light
duty motor vehicles of model years 1966 through 1974 capable- of operating
on unleaded gasoline having a research octane number of 91 or lower,[74].
These measures are also to be utilized in attaining 1975-76 motor vehicle
emission standards for new Tight-duty vehicles. By 1980 it is estimated that
90% of all light duty vehicle VWT will be accumulated by vehicles equipped
with the catalytic exhaust control device.
Extensive studies addressing the effects of catalytic converters on
automotive exhaust emissions have been conducted by the EPA and by ESSO
Research Corp.,[75]. These investigations employed measurement techniques
for the determination of exhaust emissions which condense as sulfuric acid
mist when emitted to the atmosphere. While only a trace of sulfuric acid
is exhausted by conventional exhaust systems operating on leaded fuel, it
was found that significant quantities of sulfuric acid aerosol are emitted
from vehicles equipped with oxidation catalysts. The sulfuric acid emis-
sion rates increase markedly with increasing fuel sulfur content. It has
also been found that, despite the alarming character change in particulate
emissions (sulfuric acid mist), total particulates from the oxidizer devices
are reduced from their former rate of .43 grams/mile.
The degradation of the reactive effectiveness of the catalyst, and the
generation of sulfuric acid pollution from vehicle exhaust systems pose
serious trade-off questions as to the suitability of the catalytic converter
as an exhaust emission control. The EPA is currently committed to inves-
tigate the public health consequences of vehicles operating with catalytic
converters, but as yet has not withdrawn 1975 interim Federal emission
3-77
-------
regulations which would necessitate catalytic devices to be installed on
most new 1975 Vehicles. Automobile manufacturers are currently scheduling
installation of the catalytic converters in 1975 model year vehicles to
meet these standards. EPA, in recent public hearings, has stated that sul-
furic acid emissions will not become a serious problem until new cars with
these devices comprise a larger segment of: the vehicle popultaion. Reason-
able concern over sulfuric acid emissions will be advisable, EPA recommends,
in approximately two and one-half years, by which time it is presumed new
technological developments will exist to resolve this problem. Of course
it is apparent that this technology will be quickly overdue in the critical
California Air Basins, where air quality implementation plans will insure
that 65% of the light duty vehicle population be equipped with the oxidizing
catalysts by 1977.
In addition to oxidizing catalyst retrofits, other significant mobile
source control:'measures scheduled for implementation in the South Coast
Air Basin include inspection-maintenance programs for light duty vehicles,
a nitrogen oxides control retrofit, and emission standards for new motor-
cycles beginning in 1975. Each of these control measures contribute in
part to the emission reductions expected for NO and hydrocarbons. However,
A
their effect on particulate and S02 emissions is not considered to be signi-
ficant.
Hydrocarbon and NOV exhaust emission standards have also been established
/\
for heavy-duty gasoline powered vehicles, heavy-duty diesel powered vehicles,
and motorcycles. The effect of the various motor vehicle standards in
future years is reflected in the projected emissions summary of Figure 3-7.
The rapid decrease in vehicular hydrocarbon and NO emissions is consistent
/\
with the objective of the promulgated air programs to reduce photochemical
3-78
-------
100 _
Partlculates
Motor
Vehicle
Emissions
in Four-
County
Area
80 . .
60 . .
40 . .
20 ..
I ILDMV
Motorcycles
-rlOOO
Figure 3-7 The Effect of Exhaust Emission Standards on
Pollutant Emissions from Various Vehicle
Categories
Source: Reference [4].
smog for the attainment of the ambient air standards for oxidant. This
objective is not incompatible with the goal to reach the ambient standard
for particulate matter. The role which vehicular emissions of NO and
A
hydrocarbons assume as precursors in the formation of particulates will be
effectively mitigated by the EPA strategies to reduce oxidant air pollution.
However, the control of emissions of primary particulates has not been the
target of these air programs, and the apparent benefit from the reduction
of particulate emissions indirectly resulting from this strategy actually
involves a serious trade-off pollution problem. This problem concerns the
increased generation of sulfates already discussed above.
3-79
-------
Except for the minor effects of certain transportation oriented con-
straints which would cause slight reductions in vehicle travel, the EPA
implementation plans have no provisions which address the potential manage-
ment of airborne particulate matter from vehicle tire wear. Unfortunately,
tire wear accounts for a substantial portion of the particulate emissions
caused by vehicle travel. In 1972, -.tire wear in the Four-County Area pro-
duced 15.2 tons/day of airborne particulates, or about 22% of the motor
vehicle particulate pollution. By 1980, tire wear will be responsible for
18.6 tons/day of airborne particulate emissions, which amounts to 37% of
the motor vehicle particulate pollution.
Alternative Control Options
The important options for control of motor vehicle particulate emis-
sions are:
1. Modification of fuels
2. Particulate trap devices
3. SOp scrubbers
4. Fuel substitution
5. Tire options
e> Fuel Composition - Lead Content:
Numerous studies have demonstrated the effect o.f fuel composition
on particulate emissions from motor vehicles. Typically, it has been
found that emission of particulate matter can be reduced with de-
creases in aeromatic, sulfur, or lead content in the fuel. The actual
extent of these reductions depends on a number of variables, such as
the driving test pattern, and the engine design, age, and condition.
Extensive testing has shown that approximately one-third of motor
vehicle exhaust particulate matter is composed of lead. This lead
discharge results directly from the'lead content in the fuel. Tests
show that stabilized unleaded-fuel cars emit about 40% less total
particulates than the leaded fuel cars. Carbon represents about 70%
of the total particulate matter when lead is absent in the fuel.
Current Federal regulations require that gasoline manufacturers
3-80
-------
shall provide non-leaded gasoline (maximum of .05 gm/gal) for use in
automobiles by the year 1975,[76]. This rule was constructed to insure
the use of fuels which would be compatible with catalyst exhaust
controls which are:.projected for utilization in meeting the 1975
motor vehicle requirements. Hence in the next few years there will
be a gradual change in the lead content of fuels on the market. Un-
leaded fuel will be available in increasing amounts to be consumed
primarily by those vehicles equipped with catalytic oxidizers, and
leaded fuels will be available in smaller volumes for use in the
remaining vehicles. This trend will be particularly marked in the
South Coast Air Basin, where the law calls for a catalytic oxidizer
retrofit for all light duty vehicles of model year 1966 to 1974.
An important question in the large scale production of unleaded
fuels is the effect this modification will have on the overall fuel
composition, and consequently, on particulate emissions. (The
techniques for producing the small proportion of unleaded fuels now
on the market could be very different from a large volume production.
Hence the unleaded fuels of tomorrow could be very different in com-
position from those used for exhaust emission tests today.) Lead
addition to fuel is currently the most economic path to achieving
higher octane numbers. If lead were to be removed from motor fuels,
equivalent octane numbers would have to be provided by higher con-
centrations of more expensive blending components. Depending on the
process utilized to achieve the octane rating, particulate emissions
from vehicles may or may not be increased.
After lead addition, the next most economic way to raise the
octane number of motor fuel is by increasing aeromatics content. To
upgrade an existing "clean" regular motor fuel to its typical octane
rating by addition of aeromatics rather than lead, the aeromatic con-
tent will typically be raised from 35% to 50%, [77],[78]. The effect
of aeromatics content in unleaded gasoline on particulate exhaust
emissions has been studied in several independent investigations.
According to typical findings, [79], ther would be an increase in
automobile particulate emissions of approximately 30% associated
with the projected 35 to 50% aeromatics increase.
3-81
-------
The impact of removing lead from motor fuels to overall fuel
composition is lessened somewhat by the timely policy of automobile
manufacturers to design 1971 and later model year cars to operate
with 90-91 octane fuel. Previously the automobile companies manu-r.
factured engines with higher octane requirements, as reflected by
leaded regular gasolines of 94-95 octane number which are produced to
accommodate these engines. As the 1971 and later model year auto-
mobiles began to comprise the majority of the car popultaion, there
will be a corresponding shift to lower octane motor fuel production
by the refineries. The present average lead free pool gasoline will
come close to satisfying the octane requirement for all production
vehicles manufactured in the year 1971 and after, as well as those
vehicles prior to 1971 able to operate on an ONR of 91,[80]. This
observation, plus numerous other studies of the economics of lead
removal, [78],[81],[82], has permitted the conclusion that a
universally lead-free motor gasoline supply can be attained by
1977 without major dislocations in the petroleum refining industry,
and without major changes in fuel composition.
Aside from the vehicles targeted for catalytic oxidizer instal-
lations, there will remain a significant portion of vehicles in 1977,
and even 1980, which could potentially operate on leaded fuels. The
impact of operating this vehicle segment on non-leaded fuels in terms
of particulate emission reductions is shown in Table 3-28. The data
show that total lead removal in fuels by 1977 will accomplish reduc-
tions of 28% of the motor vehicle exhaust particulate emissions in
1977, and 21% in 1980. This is based on the supported assumption,[82],
that aeromatic content will not increase appreciably in the unleaded
transition.
The cost of producing unleaded fuels depends heavily on restric-
tions limiting the aeromatic content. If aeromatic content can be
varied to produce desired octane ratings in the unleaded fuels, costs
would be minimal. Moreover, since lower octane fuels will be permis-
sible in future motor fuels, unleaded fuels will not require substanr.
tial increases in aeromatic content.
3-82
-------
TABLE 3-28. THE EFFECT OF LEAD REMOVAL IN MOTOR FUELS ON
MOTOR VEHICLE PARTICIPATE EXHAUST EMISSIONS
IN FOUR-COUNTY AREA
Projected Baseline
Participate Emissions
Tons/Dav
Motor Vehicle Category
Light duty
Heavy duty
Motorcycles and other
miscellaneous vehicles
1977
40.4
6.6
7.0
1980
35.8
7.1
7.7
Particulate Emissions
Reductions3
Tons/Dav
1977
4.4
2.6
2.8
1980
1.4
2.8
3.1
Emission reductions are based on 40% decrease attributable to all vehicles
not equipped with catalytic oxidizers when operating on unleaded fuel. It
was assumed that aeromatic content of fuel was essentially unchanged.
The portion of light duty vehicle VMT for those vehicles equipped with
catalytic oxidizer exhaust control was taken as 73% in 1977, and 90% in
1980,[2].
It is significant to the economics of unleaded fuel, that vehi-
cle exhaust from a catalytic muffler shows little sensitivity to
aeromatic fuel content. Particulate emissions from the catalytic
oxidizers are typically composed of almost 100% sulfates and water,
with very minor traces of carbonaceous particles present. In-
creased aeromatics are expected to affect gaseous hydrocarbon emis-
sions significantly, since organics are essentially eliminated by
the purposeful behavior of the oxidizing catalyst. These observa-
tions would suggest an arrangement of the vehicle gasoline pool in
which higher content aeromatics would be used to obtain octane
levels for vehicles equipped with catalytic mufflers, while low
content aeromatic fuel would be provided for vehicles operating
without the catalytic exhaust device. This motor fuel configura-
tion might provide a more economic path to octane attainment, by
permitting a higher overall aeromatic composition in the motor
gasoline pool.
3-83
-------
Another significant consideration in unleaded fuel economics
are the tradeoff benefits due to vehicle maintenance savings. These
savings are due principally to longer spark plug life, less oil
contamination, and greater exhaust system life,[78],[81].
Considering the above observations, it is apparent that the
cost of the control option, complete removal of lead in fuels, can
be implemented at less than the published estimates>[78], of .H per
gallon of gas. This amounts to a cost of $475 per ton of parti-
culate emissions controlled (Table 3-5).
f Fuel Composition - Sulfur Content:
New attention is now being drawn to the role of sulfur in motor
vehicle emissions. This is because it has been shown that vehicles
equipped with oxidation catalysts convert a substantial portion of
the sulfur in the gasoline to sulfuric acid particles. The emission
of sulfuric acid vapors directly into the atmosphere as high concen-
tration sources near transportation corridors poses an important new
health problem.
An obvious means of preventing emissions of sulfuric acid from
catalytic oxidizer equipped vehicles, or SCL from all vehicles, is
to remove the sulfur from the fuel. Desulfurization of automotive
gasolines can be accomplished with facilities similar to those now
employed to desulfurize low sulfur fuel blend stocks for fuel oil
supply to electric utilities companies. However, in most installa-
tions, the operating severity of the equipment cannot be sufficient-
ly increased for sulfur contents less than about .05%, hence, it is
necessary to construct new facilities for more complete desulfuriza-
tion. In one process which has proven effective for essentially
complete desulfurization, the Chevron Isomax, a wide range of distil-
lites, from diesel up to 1100°F end point vacuum gas oil, are eco-
nomically processed to sulfur contents less than 100 ppm. Several
oil companies are now licensed to use the Isomax process. Because
of its relatively widespread recognition in the literature, it has
been considered here as candidate equipment for implementing de-
sulfurization control.
3-84
-------
The impact of automotive fuel desulfurization to levels below
100 ppm on motor vehicle emissions is shown in Table 3-29. De-
sulfurization of the entire spectrum of vehicle motor fuels to less
than 100 ppm sulfur content would result in particulate emission
reductions of about 87% for vehicles equipped with the catalytic
mufflers. Sulfuric acid emitted from these vehicles would be re-
duced by about 99%. Prevention of SOp emissions would vary from 25
to 60% depending on the vehicle category and the type of fuel.
TABLE 3-29. THE EFFECT OF AUTOMOTIVE FUEL DESULFURIZATION (100 ppm)
ON MOTOR VEHICLE EMISSIONS IN FOUR-COUNTY AREA
Motor Vehicle Category
PARTI CULATES
Light duty
SULFUR DIOXIDE
Light duty
with catalyst
without catalyst
Heavy duty
diesel
gasoline
Motorcycles & off-road
vehicles
TOTAL (S02)
Projected Baseline
Emissions
Tons/Day
1977 1980
40.4 35.8
18.2 22.5
17.4 13.2
9.7 10.4
.8 .9
46.1 47.0
Emissions Reductions
Tons/Day
1977 1980
15.5 19.8
10.8 13.4
14.8 11.2
9.2 9.9
.7 .8
35.5 35.3
1. The portion of light duty VMT for vehicles equipped with catalytic
mufflers was taken as 73% in 1977, and 90% in 1980, [2].
2. S02 reductions are based on 85% reduction in gasoline sulfur content,
ana 95% in diesel fuel. For light duty vehicles equipped with catalytic
mufflers it was assumed that 30% of the fuel sulfur is converted to
sulfate (sulfuric acid) and the remainder is emitted as S0?.
Source: Reference [4].
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The economics of motor vehicle emission control via the desulfuri-
zation route is portrayed, in Table 3-30. The measure of desulfurization
is most cost effective as a control for S02 emissions. Taken as a joint
control for emissions of particulates and $62 combined, the cost
effectiveness is substantially enhanced. Moreover it is also
TABLE 3-30.
COST OF DESULFURIZATION OF VEHICLE FUELS FOR
CONTROL OF EXHAUST EMISSIONS
Equipment
Annual Opera- Total
tion Cost Annuali-
Capital Increase zed Cost
Cost in Millions of Dollars
Cost Per Ton of
Emission Prevented
Particulates S02
T977
1980 1977 T98C)
Desulfurization
facilities (8 V60
high severity Iso-^
max units of avg.
capacity, 40,000
barrels/day)
80
13.8
21.8 $3850 $3120 --$1680 $1690
Source: Reference [4].
evident that desulfurization facilities utilized in an effort to
prevent motor vehicle emissions are also integral to control efforts
to prevent emissions from combustion equipment and refinery process
equipment operational in the Four-County Area. The various de-
sulfurization schemes which have been examined as candidate emission
control measures for a given targeted process (combustion, motor
vehicles, refineries, aircraft) in this study, cannot be viewed as
mutually exclusive measures. There is substantial overlap in the
equipment requirements for the various desulfurization options
identified in this study, and therefore,the cost effectiveness of
any of these measures analyzed independently of its side benefits
does not provide a true credit of effectiveness.
3-86
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Particulate Trap Devices:
Several systems for removing particulate matter from exhaust
gases have been under evaluation. These devices have typically
been designed to manage particulate matter from vehicles with
standard exhaust systems (without the oxidizing catalyst), princi-
pally as a trap for lead particulate. None of the systems tested
to date have clearly demonstrated an effectiveness which would al-
low use of leaded gasoline with catalytic converters. The most
extensive testing and development of particulate traps has been
performed by Ethyl Corporation. The results of these efforts have
provided particulate trapping systems which are effective as retro-
fit emission controls for incomplete control for lead emissions
when employed in new vehicles.
Most oof the proposed particulate traps consist of an agglomera-
tor, an inertia! separator, and a filter. The agglomerator unit is
generally composed of beads or mesh, and provides a surface for
mechanically agglomerating the particles into larger sizes. The
inertial separator is generally a cyclone or combination of cyclones
used to spin out the particles at high velocity into a reservoir.
A filter is often employed at the exit of the trapping unit to re-
move smaller particles remaining in the gas stream when exiting
from the cyclone.
Preliminary data of commercial prototype retrofits units de-
veloped by Ethyl Corporation have shown that total particulate emis-
sions in standard exhaust systems may be reduced by 70% with traps
consisting of agglomeration and inertial reactions. Lead is re-
duced by more than 90%,[79],[83]. More sophisticated traps now being
developed by Ethyl have shown ability to remove nearly all (95%) lead
and particulate emissions in the standard exhaust system,[84]. These
higher efficiency systems are not engineered as retrofit units and have
limited adaptability to in-use vehicles. They are intended for
adaption to new vehicle designs whenever the vehicle is equipped
with a conventional exhaust system. Since the traps are essentially
mechanical collectors by nature, they are therefore ineffective as
a control for vapors of sulfuric acid. Particulate traps for sulr
furic acid vapors have .been developed to a limited extent. The
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technology on sulfuric acid removal is discussed in the next sec-
tion (S02)Scrubbers).
There is currently substantial indication that very effective
particulate trapping systems can be engineered and adapted to con-
trol exhaust emissions from both in-use and new motor vehicles which
utilize standard exhaust systems. This indication is based on the
apparent effectiveness of preliminary particulate trapping devices
which have been constructed with limited budgets and within a very
limited segment of the industry. A more substantial effort, sup-
ported by greater certainty of the market for the trapping devices,
would undoubtedly produce significant gains in effectiveness and
costs over the existing control devices. It appears feasible that
production of these units could be accomplished by 1977.
The preventions of particulate emissions when motor vehicles
are equipped with particulate traps is shown in Table 3-31. While
particulate traps are not applicable to a major segment of the
vehicle population (65% of light duty vehicles in 1977 and 90% in
1980), their installation on the remaining vehicle population can
effect a 46% particulate emission prevention in 1977, and 35% in
1980.
TABLE 3-31.
IMPACT OF PARTICULATE TRAPS ON PARTICULATE
EMISSIONS FROM MOTOR VEHICLES IN FOUR-COUNTY AREA
Projected Baseline
Particulate
Emissions
Motor Vehicle
Category
Light duty
with catalyst
without catalyst
Heavy duty
Motorcycles and off-road
vehicles
TOTAL
Tons/ Day
1977
20.2
20.2
6.6
7.0
54.0
1980
25.8
10.0
7.1
7.7
50.6
Prevention of
Particulate
Emissions
Tons/Day
1977 1980
0 0
16.2 8.0
5.3 5.7
3.5 3.9
25.0 17.6
Notes:
1. It was assumed that vehicles non-equipped with catalysts would utilize
leaded fuels, and that leaded fuels would be available through 1980.
2, Trap devices were assumed to be 80% efficient.
3-88
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Due to the very limited operating data available .the economics
of particulate traps are not well defined. Ethyl estimates they
would be able to provide a trap with about 80% collection efficiency
for the light duty vehicle at a cost of $14,[83]. The device would be
incorporated into a muffler, and would be rated for a lifetime of
36,000 miles, with no periodic maintenance required. This amounts
to a cost of approximately .03tf per mile per vehicle. Table 3-5
summarizes the overall economics of an implementation measure to
equip the Four-County Area with motor vehicle particulate traps.
S02 Scrubber Particulate Trap:
Because the important discovery of the interaction of sulfur and
oxidizing catalysts is relatively recent, and because of the uncer-
tainty associated with the implementation of the catalytic control
device, limited effort has been directed toward development of
auxiliary hardware to circumvent the problem that sulfur poses for
the catalytic controls. Perhaps the most promising equipment which
has been developed to be responsive to the sulfur-catalyst problem
is the molten carbonate scrubber-mufflers by Atomics International.
Designed principally to remove lead vapors in the heated portion
of the exhaust upstream of the catalytic converter, road tests have
shown the scrubber also removes essentially all the sulfur oxides
in the exhaust ,[85]. The unit operates on the basis that lead and sulfur
compounds in vehicle exhaust are acidic and will react chemically
with alkaline molten carbonate. In these reactions, lead vapor is
converted to solid lead carbonates and oxides, and sulfur dioxide
is reacted to metal sulfates.
The scrubber-muffler device utilizes heat from the engine ex-
haust in attaining the 750°F melting point of the molten carbonate
mixture rapidly. The molten mixture is aspirated out a venturi suc-
tion tube into the gas stream to facilitate rapid acid-base reac-
tions. The resulting carbonates and sulfates are retained by absorp-
tion' on the mesh. Particulates are wetted and retained in the car-
bonate mixture. Test data,[86], show the collection efficiency for
particulates in the scrubber is about 90%, making the device both an
3-89
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effective particulate and S02 control for vehicles not equipped
with the catalytic converter.
The preventions of S02 and particulate emissions when motor
vehicles are equipped with the Atomics International scrubber-muf-
fler system are shown in Table 3-32. Because of the very effective
control of S02 and particulates claimed by Atomics International,
TABLE 3-32.
IMPACT OF SCRUBBER ON S0? AND PARTICULATE
EMISSIONS FROM MOTOR VEHICLES IN FOUR-COUNTY AREA
Projected Baseline
Emissions
Tons/Day
Motor Vehicle Category
PARTICULATES
Light Duty
with catalyst
without catalyst
Heavy Duty
Motorcycles and off- road
vehicles
TOTAL
SULFUR DIOXIDE
Light Duty
Heavy Duty
Motorcycles and off-road
vehicles
TOTAL
1977
20.2
20.2
6.6
7.0
54.0
35.6
10.5
,
46.1
1980
25.8
10.0
7.1
7.7
50.6
35.7
11.3
~
47.0
Emission Preventions
Tons/Day
1977
18.1
17.2
5.6
5.9
46.8
33.8
10.0
43.8
1980
23.2
8.5
6.0
6.6
44.3
33.9
10.7
44.6
Notes:
1. The scrubber was assumed to have an efficiency of 95% for S02 removal
and 85% for particulate collection.
2. Since the scrubber removes S02 upstream of the catalytic oxidizer,
conversions of S02 to sulfuric acid particulates does not occur.
Particulates of other types are also removed by the scrubber. Hence
it is assumed that particulate emissions from vehicles with the catalytic
oxidizer will be controlled to 90% efficiency.
3. It was assumed that the scrubber-muffler unit could be adapted for
retrofit on motorcycles and heavy duty vehicles,[87].
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the overall emission control impact on the motor vehicle population is
impressive. Serious reservation should probably be maintained relative
to this preliminary analyses until further testing can be accomplished
to confirm the very encouraging preliminary data.
The cost to the consumer for the scrubber and muffler device
has been estimated at $35 for a factory installed device to $45 for
retrofit units. This compares to a typical muffler purchase and
installation cost of approximately $22. Maintenance of the scrubber
device consists of replacing the salt solution every 15,000 to 20,000
miles at a cost of $10, [85]. The live of the dual function scrubber
and muffler is estimated at 50,000 miles.
The overall economics of implementing the installation of scrub-
ber devices on the motor vehicle population as a pollution control
measure is summarized in Table 3-5 and 3-6. Because the unit has
nearly equal effectiveness either as a particulate trap or for S02
removal, it is applicable as an emission control for all the motor
vehicle categories, whether they are equipped with catalytic oxi-
dizers or not. Clearly the device is more cost effective for those
vehicles not equipped with the device since more emissions would be
prevented from these sources for an equivalent cost. Similarly,
the scrubber would be most cost effective for heavy duty vehicles
from which the greatest potential of emission preventions exists.
3.2.6 Organic Solvents
Emissions and Existing Controls
Most of the emissions originating from the use or manufacture of or-
ganic solvents occur from the process of natural or forced evaporation.
For example, when architectural coatings are applied with solvents, the
solvents evaporate into the atmosphere as the coating forms a film. In
dry cleaning operation of clothes, the solvents are removed by heat, or
forced evaporation. In general, the emissions from these activities are
hydrocarbon vapors, of varying reactivity depending on the nature of the
solvents used. With the Federal promulgation of air program implementation
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plans for the State of California, release of solvent vapors to the atmos-
phere will be prevented by stricter emission controls for dry cleaning and
degreasing operations. The user of solvents in those operations may choose
to comply with the regulation by applying emission control hardware, or by
selection of a non-photochemically active solvent.
The Federal emission controls are directed at attaining the oxidant
ambient air standards, and therefore.control stipulations for the use of
organic solvents address the prevention of reactive hydrocarbons. The
scheduled controls do not significantly affect particulate emissions, as
can be seen in Table 3-5. There are essentially no S07 or NO emissions
£ X
yielded by organic solvent operations.
A characterization of the various emission sources resulting from the
use of organic solvents in Los Angeles County revealed that painting opera-
tions in spray booths account for an overwhelming portion (85%) of their
particulate emissions. This is due to the fact that emissions from other
organic solvent operations are controlled with higher collection efficiency,
while emissions from spray booths are typically controlled to low efficien-
cies. The average emission level from a typical paint spray booth is re-
latively small, such that in the majority of cases Rule 66, which limits
total discharge of organic materials from a given piece of equipment to
less than 15 pounds of organic materials per day, is not violated. In ad-
dition, the emissions are well diluted, so as to comply with Rule 52 (which
limits the concentration of particulate matter arising from a source ac-
cording to the volume discharge) and Rules 50 and 51 (visible emissions
and nuisance rules). Table 3-33 summarizes clearly the important role
that paint spraying operations play in atmospheric pollution from organic
solvent emission sources in the Four-County Area.
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TABLE 3-33. EMISSIONS FROM PAINT SPRAY BOOTHS AND "OTHER"
ORGANIC SOLVENT OPERATIONS, FOUR-COUNTY AREA, 1972
Ooeration
Paint spraying in
spray booth
"Other"
TOTAL
No. of
Permits
4482
3470
7952
Parti cul ate Emissions
Tons/Day
Actual Preventions
6.8 1.1
.1.2 2.8
8.0 3.9
Efficiency
of
Control
13.5%
70.8%
32.8%
Source: Reference [4].
There are basically three types of devices used to capture the paint
spray of paint spray booths before the ventilation fan exhausts the booth
air to the atmosphere. They are: 1) dry baffle plates, 2) arresters or
filters, 3) a water wash. Baffle plates capture paint spray particles
with low efficiency, and are generally used as the most economic route for
protection of the spray booth operator and prevention of nuisance emissions.
Arresters or filter paper provide collection of paint particles with ef-
ficiencies up to 98%. Where filters are not practical for continuous paint-
ing operations, water washes may be used with collection efficiencies of 95%.
Additional Control Options
Since paint spraying in spray booths accounts for 85% of all emissions
from organic solvent activities, it follows that it shall be the target for
additional controls. Consultation with spray booth manufacturers revealed
the most frequently used spray booth is about 12 feet wide by 7 feet high
at the venting entry, and is usually equipped with a dry baffle collector.
It was estimated that 80% of the booths in Los Angeles are of this general
description,[88]. To improve the efficiency of the 4482 spray booths operating
with county permits, two retrofits are feasible: an arrester filter mat,
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or a water wash. In many instances ,the water wash is the more economic
route as servicing requirements are very minimal, while filters must be
replaced regularly when utilized under continuous spray operations.
The emission preventions obtained by retrofitting the present popula-
tion of paint spray booths in the Four-County Area with a water wash is
shown in Table 3-5. This control measure can yield a 77% overall preven-
tion of particulate emissions arising from organic solvent usage. Based
on an average retrofit cost of $2800 per spray booth, annualized to $280
per year at 10% interest, the total annualized cost for the entire popu-
lation of retrofits is $1.6 million. This amounts to a cost effectiveness
of $724 per ton of particulate emissions removed from the atmosphere.
3.2.7 Metallurgical Processes
Emissions
The principal emissions produced during metallurgical operations are
particulates and S02- These emissions are generated from the melting of
metals and ores in furnaces. As the feed in the furnace is melted, combus-
tibles such as grease, oil and burner fuel are burned and emitted along
with refining emissions which consist of oxide fumes of the metal consti-
tuents in the furnace melt mixture. The quantities of emissions generated
by furnace operation depends mainly on the specific melting process. The
total emissions deriving from activity of all metallurgical furnaces in the
Four County Area is tabulated in Table 3-5, 3-6 and 3-7. Emissions from
incomplete combustion constitute a small portion of the furnace effluents,
as can be seen by the relatively minor quantities of NO generated.
/\
Emission Controls
Substantial effort has already been employed throughout the metallurgical
industry to achieve a high rate of particulate collection efficiency. The
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basic control equipment generally consists of either a baghouse or an elec-
trical precipitator. A critical aspect of the successful control of furnace
dust and fumes is the hooding design. Various hooding configurations are
employed depending on the layout and shape of the furnace, and the volume
of effluent to be managed. The most difficult design problem concerns the
provision of adjustability for the hood to facilitate furnace charging and
access. For the hood to remain effective it must be positioned to allow
continuous capture of emissions arising during the charging process.
It is estimated by the Los Angeles Air Pollution Control District that
about 92% of all particulate emissions generated from metallurgical opera-
tions are prevented from entering the atmosphere , [89]. However, with regard to
emissions of S02, there are virtually no controls applied. S02 emissions
arise almost solely from lead refining, in which a substantial amount of
sulfur is present in various forms in the charge to the furnace. The melt-
ing of the charge oxidizes the sulfur compounds resulting in emission of
so2.
There are a vast number of furnaces utilized in which no emission con-
trol system has been incorporated. These furnaces are relatively small,
and the effluents which are diluted and discharged to the atmosphere by the
hooding capture systems do not constitute a violation of air pollution re-
gulations. Nevertheless, these "uncontrolled" emissions account for 58% of
the air pollution from all metallurgy operations. Table 3-34 provides a
characterization of these small furaaces and their role in emissions from
metallurgical operations.
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TABLE 3-34. CHARACTERIZATION OF FURNACE CONTROL
EFFECTIVENESS, FOUR-COUNTY AREA, 1972
Type of
Furnace
Control
None
Baghouse
Preci pita tor
Scrubbers, &
Afterburners
TOTALS
No. of
Permits
1782
483
9
224
2489
Parti culates
Emitted
from Control
System
7.2
4.7
1.4
12.3
Parti culates
Prevented
from
Emitting
0
128
3.9
132
Control i
Efficiency
o !
96.4
90.7
91.5
Source: Reference [4].
Additional Control Options
There are probably very few basic equipment modifications which would
enable significant improvements in particulate collection efficiencies for
those furnaces equipped with control systems. However it has been found
that baghouses have on numerous occasions been inadequately maintained,
resulting in poor collection efficiencies (less than 90%),[90],[91]. Bag-
house filters must be designed to be compatible with the effluent gas tem-
peratures, and condensation should be avoided or filters will saturate,
causing increased pressure drop and exhaust air flow. Bags must be shaken
regularly as furnace fumes tend to agglomerate on the fibers. It is con-
ceivable that significant performance improvements could be affected in fur-
nace emission control systems if stricter industrial maintenance practices
were implemented. However, it would be extremely difficult to assess the
benefits of such a program without extensive inventigations of prevailing emis-
sion rates and maintenance procedures. It is noted however, that the APCD
emission inventory file credits baghouse installations with a composite control
3-96
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effectiveness of 96.4% (this Is based on estimates derived, for the most
part, from theoretical calculations, and not field measurements), which,
it would seem, already presumes a high degree of maintenance consciousness.
The vast number of furnaces which currently are not equipped with emis-
sion control devices can be best retrofitted with baghouse installations
in most instances. Baghouse operating temperature is an important consi-
deration, and often temperature control must be provided for by installing
extra equipment such as convection cooling columns, or thermal insulation.
Lead melting operations are presently equipped with baghouse emission
control systems, but this equipment has no substantial effect on S02 pol-
lution. Several candidate S02 removal processes may be employed at the
baghouse effluent to obtain preventions of S02 emissions by 90%. These
controls have been discussed in Section 3.1.
The air pollution control benefits of retrofitting baghouse control
systems to furnaces which currently are vented directly to the atmosphere
are shown in Table 3-5. The retrofit measure will provide a 56% reduction
in total particulate matter emitted by metallurgical melting operations.
The impact of retrofitting lead processing furnaces with S02 cleanup
systems is shown in Table 3-6. The add-on S02 removal systems require pre-
treatment of the effluent for particulate removal, hence they must be sized
to manage the effluent of the baghouses. In furnace emission control ap-
plications, the baghouse effluent volumes are often several times that of
the furnace itself due to the dilution air used to cool the hot fumes and
prevent condensation or rapid agglomeration of matter on the baghouse
filter fabric. Based on numerous studies now being carried out to assess
the performance of S02 cleanup systems, it is estimated that 90% of the
S02 pollution generated by metallurgical activities can be eliminated.
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The cost of retrofitting uncontrolled pollutant emissions of S02 and
particulates from melting furnaces in the Four-County Area, is shown in
Tables 3-5 and 3-6. Several assumptions were necessary in the derivation
of the cost figures, and the estimates are preliminary at best. However,
the magnitude of the cost effectiveness closely parallels the cost of
other similar pollution control systems which are well documented in the
literature, and in other sections of this report. Treatment for S02 re-
moval from the effluent of lead melting furnaces is about ten times more
cost effective than particulate collection from the small uncontrolled
furnaces scattered about the Four-County Area.
3.2.8 Chemical Processing Industry . . -
Emissions
The principal emissions arising from chemical processing activities
are particulates and S02 (see Tables 3-5, 3-6, and 3-7). In future years
the .chemical industry is projected to be responsible for about 4% of all
particulate emissions, and only 2% of the S02 emission inventory. Emis-
sions of S02 are expected to be reduced dramatically by 1977 owing to
the impact of Rule 53.2 of the Los Angeles Air Pollution Control District.
Rule 53.2 will provide for reduction of 862 emissions from .the vent gas.
of sulfur recovery plants. S02 removal processes are presently being
applied in Los Angeles to reduce these emissions below 500 ppm.
Emission Controls
From the detailed itemization of emission sources and emission con-
trol equipment contained in Support Document #4, [4], it is apparent
that appreciable effort has already been invested to achieve a high rate
of particulate collection efficiency. Particulate control devices being
3-98
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used consist of mechanical collectors, wet scrubbers, electrostatic
precipitators, filters, and incinerators. The Los Angeles Air Pollution
Control District estimates that about 97% of all particulate emissions
generated by chemical processing operations are prevented from entering
the atmosphere.
The principal source of SOg emissions from the chemical industry
are sulfur recovery plants which process the offstream acid gases at oil
refineries. The acid gases are processed by the recovery plants to ob-
tain sulfur and vent gases. Previously these vent gases were incinerated
and discharged through a stack to the atmosphere. The concentration of
S02 in these stack gases varied between 2000 and 20,000 ppm. The S02
from the stacks of these plants are now being controlled by new available
technology (see Section 3.1) to a stack discharge concentration of less
than 500 ppm. S0£ removal processes have now been applied successfully
to most recovery plants in Los Angeles, but in some instances inadequate
control systems were initially installed, causing delays in the compli-
ance schedule. Scheduled equipment replacements or improvements will
insure compliance before 1977.
Alternative Controls
A substantial degree of control (reflecting the best available tech-
nology) has been accomplished over particulate emissions from the chem-
ical industry in Los Angeles County. It is presumed (in the absence of
suitable data for confirmation) that a similar level of particulate emis-
sion control has been accomplished throughout the remainder of the Four
County Area, since the process emission regulations are fairly consistent
for the various counties. With respect to the emissions of SOp the newly
3-99
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adopted regulations for sulfur recovery plants are especially stringent,
requiring commitment of oil refineries to utilization of expensive control
equipment still in its infant stages of development. These controls are
to be implemented throughout Los Angeles County, which contains all sulfur
recovery plants within the Four County Area. Owing to the impact of S02
and particulate regulations in the Four County Area, it would not appear
that significant additional emission reductions can presently be achieved
with reasonable available technology. Hence, no alternative control
measures have been identified for the chemical processing industry.
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4.0 EVALUATION OF ALTERNATIVE
CONTROL STRATEGY SCENARIOS
This chapter presents and evaluates alternative control strategy
scenarios for reducing suspended particulate levels in the Los Angeles
Region. Each control strategy is composed of a specific combination of
the control measures which were described in Chapter 3. For each strategy,
the total reduction in primary particulate, SOp* NO , and RHC emissions
is calculated. Then, these emission reductions are translated into air
quality impacts. A brief evaluation is also made of the control costs and
implementation problems associated with each strategy.
Four different control strategies are examined below. Section 4.1
describes a reasonable/implementable scenario that emphasizes fuel
desulfurization. Section 4.2 deals with a scenario based on maximal
technological control by 1977. Section 4.3 discusses a delayed strategy
based on methanol conversion; this strategy has a slow time table but
results in low emissions by 1980. None of the above strategies will
attain the primary national standard at all monitoring sites. To attain
the standard, significant reductions in growth and vehicle use as well
as industry relocation appear necessary. Section 4.4 describes the very
drastic strategy that would be required to actually attain the federal
air quality standards for particulates in the Los Angeles Region.
4.1 CONTROL STRATEGY I: A REASONABLE/IMPLEMENTABLE SCENARIO FOR
1977 AND 1980
This section presents and evaluates the first of four alternative
control strategies to be examined in this study. Control Strategy I is
called the "reasonable/implementable" scenario. It is reasonable since
4-1
-------
it avoids duplication in controls and emphasizes the most cost-effective
measures. Further, it relies on a general policy of desulfurization
which has the advantage of reducing several source types simultaneously,
(e.g., refineries, power plants, automobiles, diesels, etc.). In fact,
an alternative name for Control Strategy I would be the "desulfurization"
scenario.
Control Strategy I is implementable in a relative sense. Although
there are considerable implementation obstacles to be overcome in this
first strategy, there are even greater problems with the three strategies
to be examined later. Implementation, enforcement, and administrative
difficulties will be significant for any strategy which can bring about
substantial improvements in particulate air quality for the Los Angeles Region,
The control measures which make up Control Strategy I are listed on
the left side of Table 4-1. Detailed descriptions of these measures
can be found in Chapter 3 of this report or in Support Document #4. As
with all the control strategies proposed here, Control Strategy I assumes
that the EPA oxidant plan will be implemented.* This assumption is
intended as a recommendation of that plan. The EPA RHC/oxidant control
program is very important for reducing secondary organic particulates
as well as for controlling oxidant.
4.1.1 Impact on Emission Levels
The right hand side of Table 4-1 presents the emission reductions
to be expected from Control Strategy I in 1977 and 1980. As can be seen in
Table 4-1, the largest particulate reductions occur in the stationary
fuel combustion category (high efficiency electrostatic precipitators or
See Table 3-8 for a description of the EPA oxidant plan.
4-2
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TABLE 4-1. CONTROL STRATEGY I - REASONABLE/IMPLEMENTABLE STRATEGY FOR
1977 and 1980
Note: The EPA Oxidant Implementation Plan is Assumed as Part
of this Strategy
Source Category
A. Petroleum
Industry
B. Stationary
Fuel
Combustion
C. Organic
Solvent Use
D. Metallurgical
Processes
.
E . Chcmi cs i
Industry
Industry
G. Motor Vehicles
H. Aircraft
Operations
Proposed Control Measures
for Strategy I
A.I Improve efficiency of regenerator
unit dust control systems from 95%
to 99% (by upgrading precipitators)
A. 2 Desulfurization (to .05% S) of all
petroleum feed to catalytic
crackers
B.I High efficiency electrostatic
precipitators or high efficiency
baghouses applied to power plant
boilers, large non-power plant
boilers, and refinery heaters
(includes effect of B.2 below)
B.2 Desulfurization of fuel oils to
0.5% S with new desulfurization
technology (applied to power plant
boilers and large non-power plant
boilers)
B.3 S02 stack gas removal systems on
all refinery heaters
B.4 Low excess air firing and flue gas
recirculation for small power plant
boilers and on large/medium size
non-power plant boilers
B.5 Low excess air firing for refinery
heaters
B.6 Water injection or exhaust gas re-
circulation for stationary internal
combustion engines
C.I Water wash equipment for all paint
spray booths
D.I Baghouses for furnaces with uncon-
trolled particulate emissions
0.2 S02 removal systems for all furnace
effluent stacks
G.I Desulfurization of motor fuels to
100 PPM sulfur content
G.2 Particulate traps for motor vehi-
cles without catalytic mufflers
H.I Modification of ground operations:
towing of aircraft to avoid taxi-
idle emissions (only after land-
ing). Also, water injection for
jet engines.
Total Emission Reductions for Control Strategy I
Emission Reductions (tons/day)
1977
Susp.
Part.
2
67
6
8
13
?1
2
119
S02
51
168
33
14
36
1
303
NOX
242
26
66
...
15
349
RHC
...
6
6
1980
Susp.
Part.
2
64
6
8
17
15
3
115
S0?
51
308
34
14
35
1
443
NOX
227
24
62
...
22
335
RHC
...
8
8
4-3
-------
baghouses) and the motor vehicle category (desulfurization of motor fuels
and participate traps for vehicles without catalytic mufflers). The most
significant control of S02 is achieved by a major desulfurization program,
(for catalytic cracker feed, fuel oils, and motor fuels). Significant
NOX reductions are obtained through a control program for stationary NOX
emission sources.
The emission reductions in Table 4-1 are to be subtracted from the
emission projections for the EPA oxidant plan which is included as part
of the strategy. Table 4-2 gives the projected emissions for the 4-
County Area after application of Control Strategy I. It is noteworthy
TABLE 4-2
EMISSION PROJECTIONS FROM CONTROL STRATEGY I
FOR THE 4 COUNTY SUB-AREA
PRIMARY
SUSPENDED PARTICULATES
1972 1977 1980
EMISSION PROJEC-
TIONS UNDER EPA
OXIDANT PLAN
EMISSIONS RESULT-
IMP CDHM POMTDAI
llNb r KUrl LUIN 1 KUL
STRATEGY I
(tons/day)
(tons/ day)
(% of 1972)
178
223
104
58%
233
118
66%
NITROGEN OXIDES
1972 1977 1980
1345
1614
1266
94%
1434
1100
82%
EMISSION PROJEC-
TIONS UNDER EPA
OXIDANT PLAN^
EMISSIONS RESULT-
ING FROM rnMTRni
STRATEGY I
(tons/day)
(tons/day)
(% of 1972)
SULFUR DIOXIDE
1972 1977 1980
444
524
221
50%
535
92
21%
REACTIVE HYDROCARBONS
1972 1977 1980
1095
547
541
49%
410
402
37%
4-4
-------
that the control strategy produces reductions in each emission category
from the 1972 base emission level. Very significant decreases in primary
particulates, RHC, and especially S02 are obtained.
As noted in Section 2.3, the air quality/emission level model is
applied to the Chino monitoring site in a specialized way. For that
location, estimates are required of particulate and S02 emission reductions
from the localized source, (Kaiser/Edison complex). Table 4-3 presents
the expected reductions for the Kaiser/Edison complex under Control
Strategy I, (see Appendix A of Support Document #3 for the calculation
method). As illustrated by Table 413, the controls on metallurgical: processes,
industrial fuel combustion, and power plant fuel combustion produce signifi-
cant reductions in suspended particulate and S02 emissions from the Kaiser/
Edison complex.
TABLE 4-3
PRIMARY PARTICULATE AND S09 EMISSION ESTIMATES
FOR THE KAISER/EDISON COMPLEX IN THE WESTERN SAN
BERNARDINO COUNTY HOT-SPOT UNDER CONTROL STRATEGY I
EMISSIONS (% of 1972 LEVEL)
1977 1980
PRIMARY PARTICULATES
SOo
32%
o
54%
34%
16%
4-5
-------
4.1.2 Air Quality Impact
The emission projections for Control Strategy I have been translated
into air quality projections using the air quality model developed in
Section 2.3. The results for eight locations in the 4 County Sub-Area are
presented in Figure 4-1. It is evident that significant improvement in
total suspended particulate air quality will occur; most stations experience
about a 28 to 30 percent reduction in TSP by 1980. However, none of the eight
o
selected sites will attain the national secondary standard target level (65 jug/m
AAM), and only two sites, (Anaheim and Long Beach), will attain the national
primary standard target level, (80 ug/m AAM). Chino experiences the greatest
improvement (40 percent by 1980), but since it starts at an extremely high level,
3
Chino remains above 130 ug/m even in 1980. The other five sites all remain
above the primary standard target level in 1980, ranging from 86 ug/m at
3
Ontario to 111 ug/m at Azusa.
As indicated in Table 4-2, the effect of Control Strategy I on emission
levels is quite different for each pollutant. In 1980, primary particulate,
S02» NOx, and RHC emissions are reduced to 66 percent, 21 percent, 82 per-
cent and 37 percent of 1972 levels, respectively. However, in terms of a
gross generalization, the overall emission reduction appears to be on the
order of 50 percent. As indicated above, this emission reduction results
in an air quality improvement on the order of 30 percent. The relative
improvement in air quality is significantly less than the relative improve-
ment in emissions. This effect is basically due to high background
particulate levels in the Los Angeles Region, (30 to 60 Jjg/m at various
locations). Emission reductions affect only the non-background portion
of particulate matter; thus, total particulate levels generally change less than
in proportion to emission level changes.
4-6
-------
COASTAL AREA
LENNOX
LONG BEACH
£UU
C"l
B
00
a 100-
0
200
f>
4
00
* 100-
0
Present Controls
fc;^====:=::::nEPA Oxidant Plan
TGTj_ Control Strategy 1
B/GND
l i i ..
IUU
CO
oo
a 100-
a.
n
Present Controls
*-^^____^^ EPA Oxidant Plan
«
Control Strategy I
B/GND
i i
1 1 1 ' U 1 II
72 77 80 72 77 80
YEAR YEAR
CENTRAL VALLEY AREA
DOWNTOWN L.A. ANAHEIM
Present Controls
*s=:dr EPA Oxidant Plan
TGT. Control Strategy I
B/GND
i i i
72 ^An77 80
£UU
ro
00
a 100-
0
Present Controls
" ^_^ EPA Oxidant Plan
- t
Control Strategy I
B/GND
72 VCAD77 80
LEGEND:
TGT
B/GND.
TARGET FOR PRIMARY STANDARD
'ESTIMATED BACKGROUND
Figure 4-1 Air Quality Impact of Control Strategy I on Suspended
Particulate Levels in the Los Angeles Region
-------
EASTERN- INLAND AREA
I
CO
200
AZ U SA
ONTAR IO
R IVERSIDE
00
a
100 -
Present Controls
^-\^^ EPA Oxidant Plan
"TGT Control Strategy I
B/GND
i i i
72 77 80
WESTERN
LEGEND:
TGT. TARGET FOR
PRIMARY STANDARD
IUU
fl
a
oo
a 100-
*
SAN B
JUU
«H 200-
00
a.
1
100-
Present Controls
Control Strategy I
B/GND
1 i I
72 77 80
ERNARPINQ COUN
CHINO
Present Controls
^fffSf::::::::::^?X^ Oxidanl*Plan
\.
\v
Control Strategy I
TGT.
B/GND
1 1 1
72 77 80
zuu
Present Controls
.s ^~~~~~~-^^^EPA Oxidant Plan
=» 100-
^ TGT. Control Strategy I
5 B/GND, .
01 i 1
72 77 80
TY HOT-SPOT
Figure 4-1 Air Quality Impact of Control Strategy I on Suspended
Particulate Levels in the Los Angeles Region (Continued)
-------
4.1.3 Control Costs
The cost of implementing the control measures of Control Strategy I
is shown in Table 4-4. A scan of the cost effectiveness column shows that
the various control measures may be implemented for as low as $18. per
ton of emission controlled to as much as $3850 per ton of emission control-
led. The most costly measures (in terms of cost-effectiveness) are those
which are proposed for prevention of particulate and S02 emissions from
motor vehicles. Collectively measures G.I and G.2 (desulfurization of
motor fuels and retrofitting of particulate traps) will cost $2260 per
ton of total particulate emissions controlled. Reduction of motor vehicle
S02 emission is obtained by executing control measure G.I (desulfurization
of motor fuel) at a cost of $1680 per ton. The most cost effective
control measure for prevention of particulate emissions is modification
of jet aircraft ground operations. Initiation of this control measure
at the major airports in the 4 County Area would cost $300 per ton of
particulate emission prevented. S02 emissions are most economically
controlled by S02 removal systems in the metallurgical industry. The
cost of S02 recovery for these installations is only $101 per ton of
S02 removed. NO emissions are most economically managed by controls
applied to stationary fuel combustion emission sources. Application of
water injection or exhaust gas recirculation in stationary internal com-
bustion engines can effect NO emission control at a cost of only $18 per
/\
ton.
In general, the overall control of primary particulates constitutes
the most costly (on a dollar per ton basis) part of Control Strategy I.
The cost summary below shows that both S09 and NO emissions are controlled
c X
at substantially less cost per ton than are particulates. However, because
4-9
-------
TABLE 4-4
COST OF CONTROL MEASURES FOR CONTROL STRATEGY I
(REASONABLE/IMPLEMENTABLE SCENARIO FOR 1977 & 1980)
SOURCE
CATEGORY
IKCS EASED
ANNUAL
OPERATING
CONTROL MEASURE
INITIAL
COST - COST
MILLIONS OF I
ANNUAL UED
COST
COST EFFECTIVENESS
(t/TOIl)
Pirtlculitts SO,
A. Petroleum
B. Stationary
Fuel Com-
bust Ion
C. Organic
Solvent
Operations
D. Metallurgi-
cal Proces-
ses
E Cheinlcal
Industry
.
Industry
G. Motor
Vehicles
H. Aircraft
Operations
All Source
Categories
A.I Improve efficiency
of regenerator unit
dust control system
from 951 t« 995 by
upgrading preclpt-
tator.
A. 2 Desulfurlze (to .05X
5) all petroleum
feed to catalytic cracker
B.I High efficiency electro-
static preclpltators
or bag houses
applied to power plant
boilers, large non-power
plant boilers & refinery
heaters
B.2 Desulfurlze fuel oils
to .05* 5) with new de-
sulfuHzatlon tech-
nology (applied to power
plant boilers 4 large non
power plant boilers).
B.3 SO* removal systems on
stacks of refinery heater
B.4 Low excess air firing a
flue gas reclrculatlon
for small power plant
boilers 4 large/medium
size non-power plant
boilers
B.5 Low excess air firing for
refinery heaters -
B.6 Water Injection or ex-
haust gas reclrculatlon
for stationary Internal
combustion engines
C.I Water wash equipment for
all paint spray booths
D.I Baghoases for furnaces
with uncontrolled parti -
culate emissions
D.2 SOj removal systems
for all furnace ef-
fluent stacks.
G.I Desulfurlzatlon of motor
fuels to 100 ppm sulfur
content
G.2 Parti cul ate traps for
motor vehicle without
catalytic converters.
(These devices will
replace standard mnf-
flers)
K.I Combination of:
a) modification of
" ground operations,
towing of Jet aircraft
to avoid taxi-Idle
emissions (only after
landing - and
b) water Injection for
Jet engines '
Total cost for above
combination measures
All of controls
Hsted above
1.8
70
159
80
480
95.1
28. 5
11.0
1.3
12.6
18.6
4.0
80
28.5
1.2
13.6
14.8
896
.6
12
21.4
26.2
70
6.4
.7
- .7
.02
.1
1.5
.1.
13.8
0
.5
1.9
2.4
119
.25
19
40.0
42.5
118
15.9
5.2
1.1
.44
1.3
3.4
.5
21.8
11.5
.6
(ground
operation)
4.1
4.8
226
$ 512
$1520
$1540
__
..
_,
< 724
(1242
13850
11500
J3001
$964
$1040
$1310
__
$ 101
$1680
$740*
._
..
_.
$588
$111
$ 18
._
..
-
t89(
NOTES:
1. The cost totals do not Include costs for control measure A.2. This Is because control Measures B.2
and G.I require the sane equipment which control A.2 would use. Also, the operating costs of equip-
ment under 8.2 and G.I would Include the operating costs required by A.2.
2. Costs for each control measure are based on emission control attained In 1977. with th* exception
of control measure B.2. for which costs are based on emission control by 1980.
The cost effectiveness of paniculate and SO? control from this combination measure was calculated
based on H.I.a only because H.l.b has no substantial effect on partlculata or S02 emissions.
4-10
-------
OVERALL COSTS OF CONTROL OF SPECIFIC EMISSION TYPES
Annuali zed cost (millions)
Cost Effectiveness
($ per ton removed)
Parti culate
$ 70 $
1640
so2
145
890
NOX
$11
860
Note: Costs of those measures which effect control of more than one
pollutant type were proportioned equally among the pollutant
categories for the purposes of the above comparison.
of the different degrees of emission control obtained by the strategy
for the pollutant categories, and because of the appreciable differences
in the inventories of the pollutants, the greatest cost of the overall
strategy is consumed by control measures affecting removal of S02 emis-
sions.
The cost effectiveness of a given type of control will vary accord-
ing to the degree of pollution which is available for cleanup. For
example, S02 removal systems are shown to cost $101 per ton of S02 re-
moved when installed to manage emissions of metallurgical furnaces, but
cost $1310 per ton of S02 removed when treating effluent gases from re-
finery heaters. The difference in cost effectiveness is due in large
part to the more concentrated emissions of S02 which were available for
control from lead melting furnace effluents.
Although it would be absurd to term Control Strategy I economical,
its relative low cost and superior cost-effectiveness in relation to
the other control scenarios is a major reason for its designation as
"Reasonable/Implementable." Table 4-4 shows that the total annualized cost
of Control Strategy I is $226 million. If this amount was to be assessed
as a tax on automobile gas in the 4 County Area, it would amount to a
4-n
-------
4.5 cents per gallon price increase. Expressed in cost per capita, the
figure is $24 per person each year. The initial capital required for
the overall control plan is $896 million, and annual operating costs are
$119 million.
The most significant control measures in the plan, both in terms
of emission control quantities and overall cost, are those which would
provide for desulfurization facilities and production of low sulfur
petroleum products. If desulfurization were adopted as a universal
emission control method for the petroleum, fuel combustion, and motor
vehicle emission source categories, the effect of the desulfurization
control measures (A.2, B.2, 6.1) of Control Strategy I would overlap.
The operation of the desulfurization facilities required to produce low
sulfur motor fuels (control B.I) and low sulfur fuel oils (control B.2)
would insure the delivery of low sulfur petroleum feed stocks to the
catalytic cracker (control A.2). The overall cost of the desulfurization
strategy of the control plan would therefore, be $140 million per year,
and the initial capital required would amount to $560 million. The com-
bined cost effectiveness of the desulfurization measures to reduce S02
emissions would be $1570 per ton of SOo (with attainment of control imple-
mentation by 1980).
It should be recognized that there are many uncertainties associated
with the assessment of the cost of the control strategy. The technology
for many of the proposed emission control systems is currently in its in-
fancy, and the economics of the newly developed equipment are not well
defined. In addition, most of the control measures involve systems
which must be custom engineered to the specific application. Hence the
cost of a given type of control method may vary substantially depending
on the circumstances of the installation and the operating conditions.
4-12
-------
Cost figures were based on simplified estimative data presented in the
literature and on documented costs of existing installations assumed to
be similar to those proposed in this study. The resulting cost evalua-
tion provides the overall magnitude of the economic problems confronting
the implementation of the control strategy and a broad comparative view
between the costs of the various proposed control measures.
4.1.4 Implementation Problems
Control Strategy I is relatively the most implementable of the four
proposed control scenarios. Yet a simple inspection of the main elements
of the plan indicates there will be serious technological, socio-economic,
and administrative problems associated with its implementation. Numerous
public and private groups will sustain major adverse impacts. These
groups include refineries, industrial process corporations, the utility
companies, governmental enforcement agencies, and the public at large.
One of the most obvious implementation problems involves the status
of the control equipment technology. Some of the proposed control
measures would require the use of equipment which currently is in the
infant stages of refinement. The limited production and operating history
of desulfurization complexes, stack SCL removal systems, and motor vehicle
particulate traps raise important questions as to the suitability of
widespread legislation of these controls in the very near future.
Another obvious implementation problem concerns the high cost of
the proposed control measures. Because most of the controls are targeted
for private industry, the most substantial costs of Control Strategy I
are expected to be sustained by industrial firms. These firms include
the petroleum industry, the electric power utilities, the metallurgical
4-13
-------
industry, the air travel companies, the automobile industry, and process
industries in general. Under Control Strategy I, the petroleum industry
would bear approximately 62 percent of the total implementation cost,
amounting to an initial capital of $560 million and an annualized cost of
$140 million. While these costs would ultimately be borne by the con-
sumer, the petroleum industry would likely be quite reluctant to finance
the initial investments. In official testimony before the Committee on
Public Works in 1973, Shell Oil Company expressed concern about the
availability of capital needed for desulfurization of automobile fuels
and the physical capability of the industry to construct the needed
facilities according to the specified time tables. In addition, Shell
cautioned that desulfurization facilities would require additional
energy expenditures, which in the light of current national energy short-
ages, would impose severe hardships on society. The position taken by
Shell Oil is representative of that of other oil companies. Hence,
collectively the petroleum industry can be expected to offer powerful
resistance against the implementation of Control Stragegy I.
Equipment lead time is another very real problem associated with
successful implementation. Because many of the proposed control measures
involve newly developed control technology which has been used only
sparingly to date, the manufacturers of the associated control equipment
are not yet geared to large supply volumes such as would be needed under
the proposed implementation schedule. Hence, the ability of the equipment
manufacturers to supply some of the control systems within the allowable
lead time is very uncertain. In the case of control measures requiring large
electrical precipitators, baghouses, and desulfurization facilities, it
is not even clear that equipment manufacturers could obtain the needed
4-14
-------
raw materials prior to the actual operating emission compliance schedules.
Some control measures, such as the motor vehicle particulate traps, may
require additional development effort before they can be placed into pro-
duction status.
A fair portion of the impact of the control strategy is dependent
on its acceptance by the public. The accepatance level depends to a
great extent on an awareness of the air pollution problem and a re-
cognition of the limited means of providing immediate relief to this
problem. Traditionally, conservationist groups have been relatively
ineffective in the widespread conveyance of this awareness. Instead, the
more influential private interests have often effectively controlled
opinion. However, there is recent evidence which indicates a waivering
balance in the struggle of opinion control relating to conservationist
issues. This is true in California where public acceptance of a shore-
line conservation measure was ivoted into law amidst substantial opposition
posed by the traditional private interest elements. While such indicators
of a changing public awareness are encouraging it is unclear how wide-
spread public acceptanct of Strategy I would be.
Additional obstacles to implementation of the proposed control
strategy will very likely be generated by governmental institutions now
having jurisdication over emission source control in the 4 County
Area. Promulgation of a particulate control program by the Environmental
Protection Agency would mandate action by other appropriate governmental
agencies which might possibly be in conflict with their present official
position. For example, the implementation of controls generally requires
4-15
-------
action by 1) the state legislature, 2) California Air Resources Board,
and/or 3) the affected air pollution control districts. Execution of
the control measure requiring particulate trap retrofits to motor vehicles
could conceivably meet resistance from any of the above agencies, manifest-
ing delays in the implementation schedule, or possibly, legal suits in the
courts. While stationary source measures require no authorizing legisla-
tion or action by the Air Resources Board, local APCD's could conceivably
offer resistance to enforcement of the EPA promulgated controls if they
are sufficiently committed to conflicting emission source policies.
4.2 CONTROL STRATEGY II: MAXIMAL TECHNOLOGICAL CONTROL FOR 1977
The objective of Control Strategy II is the attainment of "maximal
technological control by 1977." Here, maximal technological control for
1977 means that the most efficient (for 1977) emission reduction measures
of Chapter 3 are selected. These measures lead to higher costs and greater
implementation problems than those associated with Control Strategy I.
The left hand side of Table 4-5 lists the control measures contained
in Control Strategy II. The reader is referred to Chapter 3 or to Support
Document #4 for comprehensive descriptions of these measures. As seen by
comparing Table 4-5 to Table 4-1, Control Strategy II differs from Control
Strategy I in four basic respects:
4-16
-------
(1) In Strategy II, SOp stack gas removal devices are used for catalytic
crackers instead of desulfurization of the cracker feed. Since
a general policy of desulfurization is not followed in Strategy II,
the less expensive but equally efficient stack gas removal devices
are chosen for catalytic crackers.
(2) In order to attain maximal SOp control from stationary fuel
combustion sources by 1977, S02 stack gas removal systems are used
in Strategy II. This avoids the delay in Strategy I associated with
fuel oil desulfurization which can be only partially implemented
by 1977.
(3) In Control Strategy II, SCL scrubber/particulate trap systems
are used on all vehicles. Strategy I calls only for particulate
traps on vehicles without catalytic mufflers. Both strategies
include desulfurization of all motor fuels.
(4) Modification of aircraft ground operations is done only after
landing in Strategy I; Strategy II also calls for modifications
before take-off. The latter may be much harder to implement
because of safety considerations. Strategy II also adds modifica-
tion of compressor airbleed for RHC control, another measure of
uncertain implementability.
It should be noted that the EPA oxidant implementation plan is specified
by Control Strategy II, as it is in all strategies considered here.
4-17
-------
TABLE 4-5 CONTROL STRATEGY II - MAXIMAL TECHNOLOGICAL CONTROL FOR 1977
Note: The EPA Oxidant Implementation Plan is Assumed as
Part of this Strategy
Source Category
A. Petroleum
Industry
B. Stationary
Fuel
Combustion
C. Organic
Solvent Use
D. Metallurgical
Processes
E. Chemical
Industry
FMi naval e
ni nera i s
Industry
G. Motor
Vehicles
H. Aircraft
Operations
Proposed Control Measures
for Strategy II
A.I Improve efficiency of regenerator
unit dust control systems from
95% to 99% (by upgrading precipi-
tators)
A. 2 S02 stack gas removal devices
for catalytic crackers
B.I High efficiency baghouses applied
to power plant boilers, large non-
power plant boilers, and refinery
heaters
B.2 SOg removal systems for all re-
finery heaters and all oil-fired
boilers
B.3 Low excess air firing and flue
gas recirculation for small power
plant boilers and on large/
medium size non-power plant
boilers
B.4 Low excess air firing for re-
finery heaters
B.5 Water injection or exhaust gas
recirculation for stationary
internal combustion engines
C.I Water wash equipment for all
paint spray booths
D.I Baghouses for furnaces with
uncontrolled particulate
emissions
D.2 S02 removal systems for all
furnace effluent stacks
G.I Desulfurization of motor fuels
to 100 PPM sulfur content and
addition of SOg scrubber/parti -
culate trap systems to all
vehicles
H.I Modification of ground opera-
tions: towing aircraft to avoid
taxi-idle emissions (before
take-off and after landing).
Also, water injection and modi-
fied compressor air bleed rate
for jet engines
Total Emission Reductions for Control Strategy II
Emission Reductions (tons/day)
1977
Susp.
Part.
2
...
64
6
8
44
5
132
S02
51
336
14
44
1
446
NOX
...
242
26
66
15
349
RHC
...
15
15
1980
Susp.
Part.
2
...
64
6
8
43
7
130
so2
51
342
14
44
2
453
NOX
...
227
24
62
23
336
RHC
...
22
22
4-18
-------
4.2.1 Impact on Emission Levels
The right hand side of Table 4-5 presents the emission reductions
resulting from Control Strategy II in 1977 and 1980. These reductions
are to be subtracted from the emission projections for the EPA oxidant
plan which is included as part of the strategy. The resulting projected
emissions from Control Strategy II in the 4 County Sub-Area are presented
in Table 4-6. A comparison with Strategy I reveals that Strategy II
attains slightly higher primary particulate and RHC control. The most
significant improvement over Strategy I is a greater reduction in S02
emissions by 1977.
TABLE 4-6
EMISSION PROJECTIONS FROM CONTROL STRATEGY II
FOR THE 4 COUNTY SUB-AREA
EMISSION PROJEC-
TIONS UNDER EPA
OXIDANT PLAN
EMISSION RESULT-
TNR FROM rnwTpni
IN\3 ri\Url UUI'1 1 KUL
STRATEGY II
(tons/day)
(tons/day)
(% of 1972)
EMISSION PROJEC-
TIONS UNDER EPA
OXIDANT PLAN
EMISSONS RESULT-
ING FROM TONTRni
STRATEGY II
(tons/day)
(tons /day)
(% of 1972)
PRIMARY
SUSPENDED PARTICULATES
1972 1977 1980
NITROGEN OXIDES
1972 1977 1980
178
223
91
51%
233
103
58%
1345
1614
1265
94%
1434
1098
82%
SULFUR DIOXIDE REACTIVE HYDROCARBONS
1972 1977 1980 1972 1977 1980
444
524
78
17%
535
82
18%
1095
547
532
49%
410
388
35%
4-19
-------
In order to apply the air quality/emission level model to Chino, esti-
mates are required of particulate and S02 emission reductions from the
Kaiser/Edison complex. Table 4-7 presents the expected emission projections
for the Kaiser/Edison complex under Control Strategy II. Here, the only
difference from Strategy I is a higher degree of S02 control in 1977,
(see Table 4-3 for a comparison)
TABLE 4-7
PRIMARY PARTICULATE AND SO- EMISSION ESTIMATES
FOR THE KAISER/EDISON COMPCEX IN THE WESTERN SAN
BERNARDINO COUNTY HOT-SPOT UNDER CONTROL STRATEGY II
EMISSIONS (% of 1972 LEVEL)
1977 1980
PRIMARY
PARTICULATES
so2
32%
15%
34%
16%
4.2.2 Air Quality Impact
The air quality impact of Control Strategy II is presented in
Figure 4-2. Results have been obtained using the particulate air quality
model of Section 2.3 for eight monitoring sites in the 4 County Sub-Area.
Under Control Strategy II, most sites experience a 31 to 33 percent im-
provement in suspended particulate air quality. However, as with Strategy
I, none of the eight selected locations attains the national secondary
standard target level, (65jug/m AAM). Two sites, Anaheim and Long Beach,
attain the national primary standard target level, (80 jug/m AAM). Again,
Chino experiences the greatest relative improvement (42 percent by 1980),
but is still at a level (127 jug/m in 1980) well in excess of the federal
standard. The other five sites remain above the primary target level, rang-
ing from 83 yg/m3 to 107 .ug/m3 in 1980.
4-20
-------
COASTAL AREA
ro
LENNOX LONG BEACH
n
8
00
a 100-
0
200
i
00
a 100
0
LEGENI
TGT.
B/GND.
Present Controls
t^==::::==::::fPA Oxidant Plan
^^\Control Strategy II
^s""-\_
1G1 1 - ^^"~
B/GND
1 1 I.M.
£UU
<»>
6
oo
1 100-
ft
Present Controls
*^^___^^ EPA Oxidant Plan
^-^ -^ A
Control Strategy II
B/GND
i i i
72 77 80 72 77 80
YEAR YEAR
CENTRAL VALLEY AREA
DOWNTOWN L.A. ANAHEIM
_ ...
-------
EASTERN-INLAND AREA
200
DO
100--
1QT._
B/GND
72
AZ U SA
Present Controls
*==9
EPA Oxidant Plan
Control Strategy II
77
80
CO
a.
72
ONTA R IO
-------
Strategy II demonstrates some slight air quality advantages over
Strategy I. The overall 1980 reductions are 31 - 40 percent for Strategy
II and 28 - 40 percent for Strategy I at the various locations. Strategy
II compares even more favorably in 1977. However, even in 1977 the ad-
vantages over Strategy I are still somewhat marginal, (3 to 4 percent
better reductions in 1977).
As with Strategy I, the air quality improvement associated with
Strategy II is smaller (on a relative basis) than the emission level
improvement. On an overall basis, emission levels are reduced more
than 50 percent by Strategy II. Ambient suspended particulate reductions
are around 33 percent. As discussed in Section 4.1.3, the relative
insensitivity of air quality to emission reductions is due to high back-
ground particulate levels in the Los Angeles Region.
4.2.3 Control Costs
The co.sts of implementing the control measures of Control Strategy
II are shown in Table 4-8. The cost-effectiveness ratios of the measures
range from as low as $18 per ton of emissions controlled to as much as $6300
per ton of emissions controlled. As in Control Strategy I, the least
cost-effective measures are those which are proposed for prevention
of particulate and SOp emissions form motor vehicles. Control measures
G.I and G.2 (desulfurization of motor fuels and retrofitting of SOp
scrubber/particul ate trap mufflers) will cost $6300 per ton of particulates
controlled, and $6070 per ton of S02 emission prevented. The least cost
effective control of NO is the combination of aircraft measures H.I.a,
A
H.l.b, and H.l.c, at $1430 per ton of NOV emissions controlled. The most
X
cost-effective measures included in Control Strategy I are also the most
cost-effective under Control Strategy II.
4-23
-------
TABLE 4-8
COST OF CONTROL MEASURES FOR CONTROL STRATEGY II
(MAXIMAL TECHNOLOGICAL SCENARIO FOR 1977)
Brecon
A. NtroleuM
industry
B. Stationary
Fuel
Combustion
C. Organic
Solvent
Operations
D. Metallurgi-
cal proem
E. DiCMlcal
Industry
F. Minerals
Industry
G. Motor
Vehicles
H. Aircraft
Operations
All Source
Cateogrles
KASlflS
A.1 throve efficiency
of regenerate unit
dust control lytte*
fro* 951 to 9» by
upgrading preclpl-
tator
A.Z SO? reMval sys-
te» on catalytic
regenerator stacks
B.I High efficiency
baghouset
applied to power
plint boilers.
large non-power
plant boilers, t
refinery heaters
B.2 SO. rawal system
for ill refinery
heaters and all
oil fired boilers
B.3 Lou excess air
firing 1 flue gas
^circulation for
seell power plant
boilers I large/
edlua site non-
power plant bolter*
B.4 Low excess air
firing for refinery
htaters
B.5 Utter Injection or
exhaust gas re-
circulation for
stationary Internal
coobustlon engines
C.I Uitar wash equip-
ment for alt
ptlnt spray booths
D.t Saghouses for
furnaces with
uncontrolled partt-
cutate emissions
0.2 SO, reaoval systces
for all furnace
effluent stacks
G.I Dtsulfurtiatlon of
otor fuels to 100
ppM sulfur content
Installation of SOj
tcrabber/partlculab
trap evffltrs on
alt vehicle*
total cost for
above corttnatlon
mature
H.I Co* In* t (on of:
a) %d
-------
Implementation of Control Strategy II would require a 62 percent
greater cost than Control Strategy I. The cost difference is due
primarily to those measures proposed for stationary fuel combusion
sources and motor vehicle sources. Strategy II would provide for
control of S02 emissions from stationary fuel combustion with S02 re-
moval systems in boiler stacks, rather than by desulfurization of fuel
oils (a slightly less effective control, especially in terms of 1977
attainment). The stack control of S02 incurs a cost of $58 million
more per year than the desulfurization option. The employment of S02
scrubber/particulate-trap mufflers to attain higher efficiency control
of motor vehicles would cost $68 million per year more than the use
of the simple particulate-trap of Control Strategy I. While the petro-
leum industry was charged with the responsibility of a $140 million
annualized cost in Control Strategy I, its expenditure under Control
Strategy II would be only $26 million per year. Hence, it is evident that
Strategy II provides for a more even distribution of costs among the
various private interest than in the first strategy.
Control of primary particulates is more costly (on a dollar per
ton basis) than control of S02 or NO . The cost summary below out-
lines the expenditures in terms of the pollutant categories controlled.
OVERALL COSTS FOR CONTROL OF SPECIFIC EMISSION TYPES
Annual i zed Cost (millions)
Cost Effectiveness
($ per ton of prevention)
Note: Costs of those measures w
lutant type were proporti(
for the purposes of the at
Particulates
$ 98
$2060
so2
$247
$1510
NOX
$ 11
$860
n'ch effect control of more than one p
)ned equally among the pollutant categ
jove comparison.
ol-
ories
4-25
-------
The combination of controls comprising the Maximal Technological
Control Strategy for 1977 would be implemented at a cost of $360 million
per year. Assessed as a tax on automobile gas in the Four County Area,
this cost would translate to a 7.3 cents per gallon price increase.
Expressed in cost per capita, the figure would be $38 per person per
year. The initial capital required for the overall control plan is
$1211 million. Annual operating costs would be $206 million.
Unlike Control Strategy I, there are no substantial overlaping im-
pacts between the control measures of Strategy II. Whereas the main
theme of Control Strategy I was desulfurization, the theme of Strategy
II could probably be termed "add-on control." Except for the desulfur-
furization of motor fuels (which really has a minor effect on motor
vehicle emissions after the S02 scrubber/particulate trap is incorporated),
all of the other major control measures of the plan involve the incorpora-
tion of add-on emission control equipment.
It should be remembered once again (see Section 4.1.3) that the
cost figures developed in this study are based on simplified estimative
data presented in the literature, and on documented costs of existing
installations assumed to be similar to those proposed in this study. The
resulting cost evaluation is, therefore, only a preliminary indicator
of the economic impact associated with the strategy implementation.
4.2.4 Implementation Problems
Because of its high cost, Control Strategy II would present more
implementation problems than Control Strategy I. Strategy II imposes
a 62 percent greater cost than Strategy I. Most of the increased cost
is sustained by the motor vehicle owner, the electric power utilities,
and process industries with fuel combustion emission sources. The
4-26
-------
latter two sectors will absorb 36 percent of the total implementation
cost, and the former, 22 percent. On the other hand, the petroleum
industry will suffer far less than under Control Strategy I (the "de-
sulfurization strategy") since its expenditures will be reduced from an
annualized cost of $140 million to $26 million. While it should be
remembered that all control costs are eventually borne by the consumer,
it is also evident that each of the private interests having responsi-
bility for initial capital outlay may be expected to lobby extensively
against the control strategy.
Most of the problems confronting the administration of Strategy II
are similar to those which would be encountered with Control Strategy
I (section 4.1.4). The plan involves essentially the same type of
control measures, although it is weighted heavily with "add-on" controls
in preference to the desulfurization control theme of the first scenario.
Because of the increased number of stack SGL removal systems required
by the plan, it may be very difficult to insure supplier delivery of
this required volume by the scheduled compliance dates. The combined
number and size of the required S02 cleanup systems would surpass that
which is already operative as installed units throughout the nation.
Implementation of the control measure which would provide for
retrofitting motor vehicles with S0« scrubber/particulate trap mufflers
could conceivably be delayed by development problems. The device is
not yet technologically refined and requires more testing and design
effort before it can be placed into production. In addition, enforcement
of the retrofit will face legal and institutional obstacles, as it must
receive legislative authorization and Air Resources Board testing
approval.
4-27
-------
As in Control Strategy I implementation will be encumbered by certain
technological problems, equipment lead time difficulties, public
acceptance problems, and administrative and enforcement complications.
While a detailed assessment of the magnitude and extent of these
difficulties is beyond the scope of this study, it is clear that the
successful execution of Control Strategy II would require an extensive
organizational mechanism to deal very rapidly with the elimination of
these technical, socio-economic, and administrative obstacles.
4.3 CONTROL STRATEGY III: A DELAYED SCENARIO FOR 1980 BASED ON
METHANOL CONVERSION
The third alternative control strategy centers around methanol
conversion for stationary combustion sources which presently burn fuel oil
or refinery make gas. Strategy III is a delayed scenario since it requires
a relatively long implementation time. It is assumed here that methanol
conversion can be fully implemented for stationary sources by 1980, but
that negligible conversion can be accomplished by 1977, (see Support
Document #4 for a discussion of market demand and construction requirements),
4-28
-------
Methanol conversion results in a very high degree of control for
participate, S0?, and NO emissions from stationary combustion sources.
^ ^
The efficiency for particulate emissions is about the same as the measures
proposed in Strategies I and II, (approximately 99 percent for the sources
which are affected). The efficiency for S02 and NOX is substantially higher
than attained by the measures in Strategies I and II. Possibly an even
greater advantage of the methanol conversion strategy is the impact on
projected energy problems. Methanol can be produced from low grade coal
or even from certain types of refuse. The methanol conversion scheme
can thus help to alleviate the supply problem associated with petroleum
based fuels. A detailed description of the methanol control measure
and associated impacts, costs, and implementation problems can be found
in Support Document #4.
The left hand side of Table 4-9 list the control measures to be
included in Strategy III. As noted above, the principal change from
Strategies I and II is the substitution of methanol conversion in place
of several other controls for stationary combustion sources. The re-
mainder of Strategy III is identical to Strategy I, (the reasonable/
implementable strategy), with two exceptions. These exceptions have
been made in order to make Strategy III more compatible with a policy
of methanol conversion in the long run. In the long term, (post 1980),
it might prove best to convert nearly all petroleum fuel users (mobile
as well as stationary) to methanol on a nationwide basis. Accordingly,
there would be a general phasing out of petroleum fuel production and use.
To be compatible with this phasing out, exhaust gas treatment add-on de-
vices are chosen in Strategy III for both catalytic crackers and automobiles
rather than the desulfurization options for cracker feed and motor fuel
which represent long-term capital commitments in the petroleum industry.
4-29
-------
TABLE 4-9 CONTROL STRATEGY III - A DELAYED SCENARIO
FOR 1980 BASED ON METHANOL CONVERSION
Note: The EPA Oxidant Implementation
Plan is Assumed as Part of
This Strategy
SOURCE CATEGORY
A. Petroleum
Industry
B. Stationary
Fuel
Combustion
C. Organic
Solvent
Use
D. Metallurgical
Processes
E. Chemical
Industry
F. Minerals
Industry
G. Motor
Vehicles
H. Aircraft
Operations
PROPOSED CONTROL MEASURES
FOR STRATEGY III
A.I. Improve efficiency of regenerator
unit dust control systems from 952!
to 99% by upgrading precipitators.
(Includes reduction in operations
from B.I . below.
A. 2. SO. stack qas removal devices for
catalytic crackers. (Includes re-
duction in operations from B.I.
below).
B.I. Conversion of all boilers and
heaters using fuel oil or refinery
make gas to methanol fuel by 1980.
B.2. Water injection or exhaust gas
recirculation for stationary in-
ternal combustion engines.
C.I. Water wash equipment for all spray
booths .
D.I. Baghouses for furnaces with un-
controllable paniculate emissions.
D.2. S02 removal systems for all
furnace effluent stacks.
G.I. SOj scrubbers/particulate trap
systems for all vehicles.
H.I. Modification of ground operations:
towing. of aircraft to avoid
taxi-idle emissions, (only after
landing). Also, water injection
for jet engines.
EMISSION REDUCTIONS (TONS/DAY)
1977
SUSP.
PART.
2
6
8
42
2
so2
51
44
1
N0x
...
66
14
15
RHC
...
6
1977
TOTAL EMISSION REDUCTIONS FROM CONTROL STRATEGY III
(TONS/DAY)
SUSP.
PART.
60
so2
110
NOX
81
RHC
6
1980
SUSP.
PART.
2
64
6
8
...
41
3
so2
51
379
...
14
45
1 '
NOX
328
62
...
22
RHC
...
8
1980
SUSP.
PART.
124
so2
490
N0x
412
RHC
8
4-30
-------
4.3.1 Impact on Emissions Levels
The right hand side of Table 4-9 presents the emission reductions
to be expected from Control Strategy III in 1977 and 1980. As evidenced
by the table, methanol conversion of boilers and heaters is the dominant
control measure. Since methanol conversion is not attained until 1980,
the 1980 emission reductions are much larger than the 1977 reductions.
The emission reductions of Table 4-9 are to be subtracted from the
baseline emission projections for the EPA oxidant plan which is included
as part of the proposed control strategy. Table 4-10 presents the resulting
emission projections for the 4 County Sub-Area under Control Strategy III.
A comparison with Strategies I and II, (Tables 4-2 and 4-6), reveals that
Strategy III leaves greater particulate, S02> and NO emissions in 1977
but attains considerably lower S02 and NOX levels by 1980.
TABLE 4-10
EMISSION PROJECTIONS FROM CONTROL STRATEGY III
FOR THE 4 COUNTY SUB-AREA
PRIMARY NITROGEN OXIDES
SUSPENDED PARTICULATES
1972 1977 1980 1972 1977 1980
EMISSION PROJEC-
TIONS UNDER EPA
OXIDANT PLAN
EMISSIONS RESULT-
ING FROM mWTRni
STRATEGY III
(tons/day
(tons/day
(% of 1972)
EMISSION PROJEC-
TIONS UNDER EPA
OXIDANT PLAN
EMISSIONS RESULT-
ING FROM CONTROL
STRAGEGY III
(tons/day)
(tons/day)
(% of 1972)
178
223
163
92%
233
109
61%
1345
1614
1533
114%
1434
1022
76%
SULFUR DIOXIDE REACTIVE HYDROCARBONS
1972 1977 1980 1972 1977 1980
444
524
414
93%
535
45
10%
1095
547
541
49%
410
402
37%
4-31
-------
In order to apply the air quality/emission level model to the Chino
monitoring site, estimates are required for the effect of each strategy on
particulate and SOp emissions at the Kaiser/Edison Complex. Table 4-11
presents the expected particulate and SOg emissions for Kaiser/Edison
under Control Strategy III. The difference in Strategy III from the first
two strategies is demonstrated even more dramatically here. The delayed
scenario initially yields an increase in particulate and SO^ emissions
from Kaiser/Edison, followed by a drastic decrease as methanol conversion
is implemented between 1977 and 1980.
TABLE 4-11
PRIMARY PARTICULATE AND SO, EMISSION ESTIMATES
FOR THE KAISER/EDISON COMPCEX IN THE WESTERN SAN
BERNARDINO COUNTY HOT-SPOT UNDER CONTROL STRATEGY III
EMISSIONS (% of 1972 LEVEL)
1977 1980
PRIMARY PARTICULATES
SOo
108% 34%
115% 5%
4.3.2 Air Quality Impact
Figure 4-3 presents the air quality impact of Control Strategy III
at the eight monitoring sites in the 4 County Sub-Area. The delayed
nature of the methanol control strategy is evident in Figure 4-3. In
1977, only marginal improvements in air quality are attained, (about 10
percent better than 1972 levels at most stations). Between 1977 and 1980,
significant reductions in particulate levels are achieved at each station.
4-32
-------
COASTAL AREA
LENNOX
LONG BEACH
I
O.)
CO
-------
EASTERN- INLAND AREA
AZU SA
ONTAR IO
R IVERSIDE
2UU
a
00
Soo-
*
.*»
co
Present Controls
' - JJ[A Oxldant Plan
Control Strategy Iir^«
TGT.
B/GND
i i i
72 77 80
WESTERN
LEGEND:
TGT. TARGET FOR
PRIMARY STANDARD
tvv
n 1
_B
5 10°1
*
SAN B
9AA
JUU
«B 200-
oo
a.
i
100-
o
Present Controls
TGT. " ====:tl!A^dant
Control Strategy III
B/GND
1 i |
72 77 80
ERNARDINO COUN
CHINO
Present Controls
. -^^^^Plan
\,
Control Strategy Ilr^
TGT.
B/GND
t 1 1
^uu
Present Controls
*% " ' *^^^^^^Idlnt
-1 100- Control Strategy III~~*
^ TGT.
5 B/GN,D,
01 i
72 77 80
TY HOT-SPOT
72
77 80
Figure 4-3 Air Quality Impact of Control Strategy ill on Suspended
Particulate Levels in the Los Angeles Region (Continued)
-------
In 1980, the air quality levels under Strategy III are very similar
to those under Strategy II, (the maximal technological scenario). Most
sites experience a 30 to 34 percent improvement in suspended particulate
air quality by 1980. No stations reach the target level for the secondary
o
national particulate standard, (65 ug/m ). Anaheim and Long Beach attain
the national primary standard target level, (80 ug/m ). Chino experiences
the greatest improvement (42 percent by 1980), but still remains at the
highest level of all the sites, (127 >jg/m in 1980). These are almost
exactly the same results as Strategy II for 1980. The main difference be-
tween the air quality impacts of Strategies II and III is that the latter
achieves only about a third of the improvement associated with the former
in 1977.
4.3.3 Control Costs
The implementation costs of the delayed scenario for 1980 based on
methanol conversion are shown in Table 4-12. The strategy is essentially
the same as Control Strategy I (Reasonable/Implementable Plan) with the
main exceptions that control of fuel combustion equipment is accom-
plished by conversion to the cleaner burning methanol fuel, and the
desulfurization measures of Strategy I have been omitted (in anticipation
of the eventual universal conversion of all petroleum fuel use to methanol),
These significant distinctions produce a total cost for the Methanol
Strategy of $235 million per year, which is nearly the same as the imple-
mentation cost of Control Strategy I (Reasonable/Impleraentable). However,
the initial capital required for execution of the plan is $1650 million,
substantially more than each of the first two control strategies. These
high capital costs are offset by the fact that there are no increases in
operating costs for the methanol production facilities over the previous
4-35
-------
TABLE 4-12
COST OF CONTROL MEASURES FOR CONTROL STRATEGY III
(DELAYED METHANOL CONVERSION SCENARIO FOR 1980)
SOURCE
CATEGORY
A. Petroleuo
Industry
9. Stationary
Fuel
Conbustlon
C. Organic
Solvent
Operations
0. Metallurgi-
cal process
E. Chemical
Industry
F. Minerals
Industry
G. Motor
Vehicles
H. Aircraft
Operations
All Source
Categories
CONTROL
MEASURE
A.I Improve efficiency
of regenerator unit
dust control system
from 95S to 99J by
upgrading pred pi-
ta tor
A. 2 SO. removal system
on catalytic regene-
rator stacks
B.I Conversion of all
boilers and heaters
using fuel oil or
refinery make gas
to methanol fuel by
1980.
B.Z Mater Injection or
exhaust gas redrcu-
latlon for stationary
Internal combustion
engines
C.I Water wash equip-
ment for all
Paint spray booths
D.I Baghouses for
furnaces with
uncontrolled parti-
cipate emissions
B.Z SO, removal systems
for all furnace
efficient stacks
G.I SO. scrubber/
participate trap
mufflers for all
motor vehicles.
H.I a) Modification of
ground operations:
Towing of aircraft to
avoid taxi-Idle emis-
sions (only after
landing) and
b) Water Injection for
( jet engines
total cost for a and b '
All of above control
measures
INCREASED
ANNUAL
INITIAL OPERATING AHNUAL1ZED
COST COST COST
MILLIONS OF DOLLARS
1.8 .6 .25
28 .7 3.8
1422 0 142
1.3 .2. .44
12.6 .1 1.3
18.6 1.5 3.4
4.0 .1 .5
147 41 79
1.2 .5 .6
13.6 1.9 4.1
14.8 2.4 4.7
1650 47 235
COST EFFECTIVENESS
<$/TON)
Suspend*
PartlculaUs S02 NO,,
$ 512
$6000*
$724
$1242
....
$5300
ISO"
$ 193
$1030*
$ 101
....
$4820
370*
....
$1190*
$ IB
$890
a. This control measure Is proposed for control of participates. NO and SO. collectively. The cotfclned cost
effectiveness of the measure for all three erlsslon typ»* Is $505 per tofl reaoved.
b. The cost effectiveness of paniculate and SO. control fran this neasur* MS calculated based on (H.I.a)
only because (H.l.b) has no substantial effect on paniculate or S02 emissions.
4-36
-------
operating cost of facilities producing fuel oil. This, of course, is
possible because of the increased cost of raw petroleum stocks in the
past two years relative to the cost of coal, which will be used in the
production of methanol.
The conversion of fuel oils to methanol fuel in boilers and heaters
is the most significant control measure contained in the plan. Sixty-two
percent of the total annualized implementation cost would be accounted for
c
by the conversion. The remainder of the cost of implementation would
be due almost entirely to the motor vehicle control measure, (SCL scrubber/
particulate trap muffler retrofit). This measure would incur a cost of
$79 million per year.
It should be recognized that the overall implementation costs shown
in Table 4-12 are reflective only of the plan status in 1980. Whereas
in the "Desulfurization" and "Add-on-Control" Scenarios there were no
substantial cost pertubations expected in the far term, the methanol
conversion of the "Delayed Scenario" would eventually (after 1980) be
expected to expand to other petroleum products such as motor fuels and
aircraft fuels. With engines designed to be operative on the methanol
fuel, it is expected that federal emission regulations for aircraft and
motor vehicles eould be attained and surpassed. This occurence would
virtually eliminate the need of petroleum fuels and the associated
emission control equipment required to manage the pollution derived from
consumption of the petroleum products. Hence the cost effectiveness
and emission removal effeciency of Control Strategy III would improve in
the far term, making this strategy the least costly of the alternate
scenarios.
4-37
-------
Since Control Strategy III is in harmony with national goals of
energy self sufficiency, it is evident that its cost effectiveness
cannot be weighed only in terms of air pollution abatement. While it is
unclear how prices of methanol fuel will vary in the inflationary markets,
it appears that there are important cost factors in its favor. Methanol
can, for example, be produced from low quality coal, of which there are
ample domestic reserves to supply the nation for many decades. In
addition, it can be produced from any other carbonaceous substance which
can be burned to create the required synthesis gas needed for methanol
production. Eventually it is expected that raethanol will be produced by
chemical formation of synthesis gas, eliminating the need to consume
fossil fuels. While the cost relationships for these factors cannot be
assessed within the scope of this study, it is apparent that they would
cause significant impact on the long term comparison of the four control
scenarios considered in this study.
4.3.4 Implementation Problems
Control Strategy III is confronted with many of the same technological,
socio-economic, and administrative problems associated with the first two
control scenarios. (See Sections 4.1.4 and 4.2.4). The strategy is
essentially the same as that of Control Strategy I except for the addition
of the methanol conversion measure, which replaces the "add-on-controls"
for stationary fuel combustion sources and the fuel desulfurization
measures. The extent of the implementation problems due to these differ-
ences depends largely on the role of the petroleum industry in the execu-
tion of the proposed control measures. Implementation of the methanol
conversion measure (B.I) would incur a substantial market loss to the
petroleum industry, with even larger losses imminent with expanded future
4-38
-------
conversions for motor and aircraft fuels. Unless the petroleum industry is
able to participate in the conversion measure, it would not be able to avoid
severe financial setbacks imposed by the plan.
Another obvious implementation problem associated with the plan is the
high capital cost of the methanol conversion measure. This measure alone
will require an initial capital of $1422 million, imposing a severe fund-
ing burden on potential methanol suppliers, and raising questions as to
whether governmental subsidies should be provided.
While there are numerous difficulties concerning implementation of
Strategy III, there are also beneficial side effects to be derived. The
plan is consistent with the nation's energy sufficiency program. Also,
since it appears that methanol fuel will be cost competitive with fuel
oils, there is a built-in incentive for commitment by private interests
to exploit this market. Of course none of the benefits can be realized
in the near term; the four to five year lead time required to construct
the expensive methanol producing plant is one of the main drawbacks.
4-39
-------
4.4 CONTROL STRATEGY IV: A DRASTIC SOURCE-RELOCATION/VMT-REDUCTION
STRATEGY TO ATTAIN THE PRIMARY AIR QUALITY STANDARD BY 1980
None of the first three control strategies examined above attained
the national primary standard for suspended particulates at all monitoring
sites in the Los Angeles Reion. In fact, in 1980, suspended particulates
at several locations are.still about 25 percent above the target level
for the primary standard with all three of the strategies considered.
Chi no, in the Western San Bernardino County Hot-Spot, still would have
levels about 60 percent above the primary standard target level. It is
evident that significantly more stringent controls are necessary to reach
the primary standard for particulates at all locations in the Los Angeles
Region.
This section describes a drastic control strategy designed to attain
the primary national air quality standard for particulates. Control Strategy IV
is drastic in the sense that severe "non-technological" controls have
been added to the maximal.technological controls as given by Strategy
II. These non-technological controls include a comprehensive relocation
program for all major types of stationary sources as well as a gasoline
rationing program to reduce vehicle traffic by 50 percent. The socio-
economic discruptions associated with this control strategy would be
staggering, and it is not expected that Strategy IV would really be carried
out. Accordingly, the present discussion is in some sense an academic
exercise. We are investigating what type of strategy would be required
to attain the national primary standard for particulates, rather than proposing
a strategy for actual implementation.
The left hand side of Table 4-13 lists the control measures which are
included in Strategy IV. The technological measures are identical to those
in Control Strategy II, (the maximal technological control scenario). To
4-40
-------
TABLE 4-13
CONTROL STRATEGY IV - A DRASTIC SOURCE RELOCATION/
VMT REDUCTION STRATEGY TO ATTAIN THE PRIMARY AIR
QUALITY STANDARD BY 1980
NOTE: The EPA Oxidant Implementation Plan is
Assumed as part of this strategy
Source Category
Proposed Control Measures
for Strategy IV
Emission Reductions (tons/day;
Susp,
Part,
1977
so2
«°x
RHC
1980
Susp.
Part.
S82
"°»
RHC
MAXIMAL TECHNOLOGICAL CONTROLS
A. Petroleum
Industry
B. Stationary
Fuel
Combustion
C. Organic
Solvent Use
D. Metallurgical
Process
E. Chemical
Industry
F. Minerals
Industry
G. Motor
* Vehicles
H. Aircraft
Operations
A.I Improve efficiency of regenerator
unit dust control systems from 951
to 991. (by upgrading precipl-
tators)
A. 2 S02 stack gas removal devices
for catalytic crackers
B.I High efficiency baghouses applied
to power plant boilers, large non-
power plant boilers, and refinery
heaters
B.2 S07 removal systems for all re-
finery heaters and all oil-fired
boilers
0.3 Low excess air firing and flue
gas recirculatlon for snail power
plant boilers and on large/
medium size non-power plant
boilers
B.4 Low excess air firing for re-
finery heaters
B.5 Water injection or exhaust gas -
recirculatlon for stationary
internal combustion engines
C.
Water wash equipment for all
paint spary boths
D.I Baghouse for furnaces with
uncontrolled particulate
emissions
0.2 SO* removal systems for all
furnace effluent stacks
G.
Desulfurlzatlon of motor fuels
to 100 PPM sulfur content and
addition of SO- scrubber/part f-
culate trap systems to all
vehicles
H.I Modification of ground opera-
tions: towing aircraft to
avoid taxi-idle emissions
(before take-off and after
landing). Also, water Injec-
tion and modification of com-
pressor air bleed rate for Jet
engines
Emission Reductions From the Technological Controls
2
67
6
8
-
44.
5
132
51
336
44
1
446
242
26
66
15
349
...
...
...
...
15
15
2
64
6
43
7
130
51
342
14
44
2
453
...
227
24
62
...
...
...
23
336
...
22
22
NON-TECHNOLOGICAL CONTROLS
Petroleum
Refining
Stationary
Source Fuel
; adjust ion
liners Is
Industry
Chemical
ndustry
11 re raft
pe rations
Metallurgical
Processes
Motor
Vehicles
-
Relocation or the
development of new
technology to achieve
751 further reduction
of partTcuTate. SOg. and
NOX emissions from the levels
remaining with the above con-
trols In 1930.
Relocation or the development of
new technology to achieve 901
further reduction of particulate
and SO? emissions from the levels
remaining with the above controls
In 1980.
Gasoline rationing to achieve a
501 reduction In VMT In 1980.
(Includes effect on RHC emissions
from petroleum marketing)
Emission Reductions from the Non-Technological Controls
Total Emission Reductions for Control Strategy IV
132
446
349
15
1
16
9
8
22
9
10
71
201
6
28
1
8
6
1
...
50
603
51
237
17
...
332
637
973
...
170
170
192
4-41
-------
these are added two types of non-technological controls: stationary
source relocation and gasoline rationing.
Strategy IV specifies a relocation program to achieve a 75 percent
emission reduction for petroleum refineries, stationary fuel combustion
sources (power plants, industrial boilers, refinery heaters, etc.),
mineral industries, chemical industries, and aircraft operations. In
order to achieve greater improvement at the Chino location, a relocation
program to attain 90 percent emission reduction is specified for
metallurgical processes.* As indicated in Table 4-13, the development
of new control technology to achieve the reductions is allowed as a
possible option to relocation.
A 50 percent decrease in vehicle miles travelled (VMT) is also
specified by Strategy IV. As indicated in Section 3.1.4, the only effec-
tive way to attain this magnitude of traffic reduction appears to be
through a gasoline rationing program.
It should be noted that the severity of the relocation and gas
rationing controls would be lessened by other growth, conservation, and
transportation policies. In fact, we would certainly recommend that
such policies be adopted along with relocation if Strategy IV were act-
ually implemented. A no growth policy for vehicle traffic between 1975
and 1980 would reduce VMT by about 10 to 15 percent from the presently
projected 1980 levels.** No growth for fuel combustion sources between
1975 and 1980 would reduce presently projected 1980 emissions by about
25 percent. However, the impact of growth policy alone (as well as of other
* The Chino site appears to be strongly affected by Kaiser Steel/Edison
Electric emissions.
** See Support Document #2 for projected growth rates from various sources,
4-42
-------
conservation and transportation policies) falls well short of the severe
emission reductions needed to attain the particulate air quality standards.
Thus Control Strategy IV calls for the more stringent measures of re-
location and gas rationing.
4.4.1 Impact on Emission Levels
The right hand side of Table 4-13 lists the emission reductions associated
with the control measures in Strategy IV. Greater total reductions are
obtained in 1980 than in 1977 since the relocation and vehicle use
restrictions are not to be implemented until 1980. The total emission
reductions in Table 4-13 are to be subtracted from the emission pro-
jections for the EPA oxidant implementation plan which has been included
as part of the strategy. The resulting emission forecasts under Control
Strategy IV are given in Table 4-14. It can be seen that very strict
overall control of particulate, SO,, NOV> and RHC emissions is attained
L. A
in 1980 by the drastic measures of Strategy IV.
TABLE 4-14
EMISSION PROJECTIONS FROM CONTROL STRATEGY IV
FOR THE 4 COUNTY SUB-AREA
EMISSION PROJEC-
TIONS UNDER EPA (tons/day)
OXIDANT PLAN
EMISSIONS RESULT- (tons/day)
ING FROM CONTROL
STRATEGY IV (% of 1972)
EMISSION PROJEC-
TIONS UNDER EPA (tons/day)
OXIDANT PLAN
EMISSIONS RESULT- (tons/day)
ING FROM CONTROL
STRATEGY IV (35 of 1972)
PRIMARY
SUSPENDED PARTICULATES
1972 1977 1980
NITROGEN OXIDES
1972 1977 1980
178
223
91
51%
233
32
18%
1345
1614
1265
94%
1434
461
34%
SULFUR DIOXIDE
1972 1977 1980
444
A A?
524
78
18%
535
32
7%
REACTIVE HYDROCARBONS
1972 1977 1980
1095
547
532
49%
410
218
20%
-------
In order to compute air quality changes at the Chi no monitoring
site, estimates are required of particulate and S02 emission reductions
from the Kaiser/Edison complex. Table 4-15 presents these projections
for Control Strategy IV. The very high degree of control proposed in
Strategy IV for stationary source fuel combustion and for metallurgical
processes brings about more than a 95 percent reduction in particulate
and S02 levels by 1980.
TABLE 4-15
PRIMARY PARTICULATE AND S09 EMISSION ESTIMATES FOR
THE KAISER/EDISON COMPLEX IN THE WESTERN SAN BERNARDINO
COUNTY HOT-SPOT UNDER CONTROL STRATEGY IV
EMISSION (% of 1972 LEVEL)
1977 1980
PRIMARY PARTI CULATES
so2
32%
15%
4%
3%
4.4.2 Air Quality Impact
Figure 4-4 presents the impact of Control Strategy IV on suspended
particulate air quality at eight locations in the Los Angeles Region. The
stringent emission reductions in 1980 bring particulate levels down to at
least the national primary standard target C80 jig/m3 AAM) at each location.
Five of the eight stations, (Lennox, Long Beach, Downtown, Anaheim, and
Ontario)', also attain the national secondary standard target level,
o
(65 ug/m .AAM). The other three stations, (Asuza, Riverside, and Chino),
2
are right at or just below 80 jjg/m AAM.
With the severe emission reductions of Strategy IV, the air quality
levels at each location approach background levels. The differences in
4-44
-------
COASTAL AREA
LENNOX
LONG BEACH
-p.
en
£VU
fl
B
00
* 100-
0
200
n
a
00
* 100-
0
LEGENI
TGT.
B/GND
Present Controls
^^g^^^^TSPA Oxidant Plan
^"^^Control Strategy IV
TGTj_ ^~"*x.
B/GND
i i i
1 1 1
72 77 80
YEAR
CENTR
DOWNTOWN L.A.
Present Controls
"=^~ EPA Oxidant Plan
^~~^-~^Control Strategy IV
TGI. ^*>^^
B/GND
1 1 1
72 YEAR77 8°
):
TARGET FOR PRIMARY STANDARD
-------
EASTERN- I NLAND AREA
200
AZ U SA
00
a.
100--
Present Controls
EPA Oxidant Plan
Control Strategy IV
72
200
ONTAR IO
B
CO
' a.
100-
Present Controls
EPA Oxidant Plan
TGI.
B/CND Control Strategy IV'
77 80
4-
200
RIVERSIDE
B
00
72
77 80
Present Controls
EPA Oxidant*Plan
a- IQO- -Control Strategy I
5 TGT_.
< B/GND.
72
77 80
WESTERN SAN BERNARDINO COUNTY HOT-SPOT
LEGEND:
TGT.
B/GND
-TARGET FOR
PRIMARY STANDARD
ESTIMATED BACKGROUND
300
m 200-
100-
B/GND
72
CHINO
Present Controls
*==3
EPA OxidanWlan
77 80
Figure 4-4 Air Quality Impact of Control Strategy IV on Suspended
Particulate Levels in the Los Angeles Region (Continued)
-------
air quality at the various locations are then dominated by the relative
background levels. The basic reason why Asuza, Riverside, and Chi no
attain only the primary standard while the other stations attain the
secondary standard is that the former three locations have the highest
estimated background levels, (53 to 60 yg/m ). As noted previously,
these high background* levels are the principal reason why very
stringent control is needed to attain the primary standard.
4.4.3 Control Costs
Control Strategy IV combines the high costs of the Maximal Tech-
nological Control Strategy with prohibitive costs of drastic administra-
tive controls. The cost of the relocation measure, requiring the
major industries to relocate 75 percent of their emission sources or to
provide new technology to control these emissions an equivalent degree,
is probably insurmountable.** It is not clear which cost would be greater,
the development of new control technology or relocation. If current
control technology were used to comply with the measure, the cost of
implementation could conceivably exceed the capital worth of the industrial
facilities themselves. Relocation would, in many cases, impose similar
costs. Quantitatively assessing the impact of these costs which would
undoubtedly force many concerns out of business, is beyond the scope of
this study.
*The reader should note that background refers to non-controllable origin
categories in this report. These origin categories include suspended
soil dust from man-made activities and man-made sources exterior to the
Los Angeles Region as well as natural sources.
**The reader is reminded that a 75% further reduction is required from the
"maximal technological control" level.
4-47
-------
4.4.4 Implementation Problems
Because of the severe socio-economic disruptions which would be
imposed by Control Strategy IV, it is considered unimplementable. It is
unlikely that the extreme costs imposed on industrial interests could be
recovered unless massive subsidies were incorporated in the plan. While
resistance from influential firms would pose great implementation problems,
strong resistance would also be generated from the general public. Personal
livelihoods would be threatened and life styles would be severely disrupted.
These impacts would be difficult to predict or measure and are not within
the evaluative scope of this report. Suffice it to say that total attain-
ment of the particulate air quality standards in Los Angeles is not imple-
mentable within the modus operandi of the prevailing political and
socio-economic framework.
4-48
-------
5.0 CONCLUSIONS AMD RECOMMENDATIONS
This chapter presents the conclusions and recommendations which have
resulted from the various phases of this investigation. Section 5.1
deals with proposed control strategies. The four alternative control
scenarios are compared and recommendations are made as to preferred stra-
tegies. Section 5.2 summarizes the conclusions reached by the technical
support analyses performed in the study. The limitations of these analy-
ses are discussed and recommendations are made for further research
efforts.
5.1 CONTROL STRATEGY RECOMMENDATIONS
The previous chapter formulated and evaluated alternative control
strategies designed to reduce suspended particulate .levels in the
Los Angeles Region. These strategies consisted of various combinations
of emission control measures for primary particulates and for gaseous
precursors of secondary particulates. The evaluation included analyses
of emissions reductions, air quality impacts, control costs, and implemen-
tation problems. Table 5-1 summarizes the overall air quality improvement,
economic costs, and implementation difficulties associated with each of .
the strategies.
As noted in the previous chapter, Control Strategy IV (the air quality
standard attainment strategy for 1980) is not considered implementable.
As indicated in Table 5-1, this strategy would involve great socio-economic
disruption; its implementation would be oppossed by very strong public and
private forces. We do not think that Strategy IV would serve as a viable
approach to particulate air quality policy in the Los Angeles Region, and
we do not recommend it as a policy goal.
5-1
-------
An overall comparison of Strategies I and II, (Table 5-1), reveals
that Strategy II (maximal technological control) achieves small air
quality improvements over Strategy I (reasonable/implementable scenario)
at the expense of extra economic costs and more difficult implementation
problems. A recommendation of one of these strategies over the other
should be based on a comparison of the marginal reductions in pollution
damage costs vs. the marginal increases in control and administrative
costs. The quantitative analysis required to make this comparison is not
within the scope of the present effort. However, through a qualitative
examination of the problem we have concluded that Strategy I appears
preferable to Strategy II. The relative air quality improvement in
Strategy II, (about 3 to 4%), does not seem to compensate for the extra
costs and implementation problems associated with that strategy.
A comparison of Strategy II with Strategy III reveals that both plans
attain the same overall air quality level by 1980. However, the delayed
scenario based on methanol conversion (Strategy III) achieves much less air
quality improvement by 1977. Although the delayed methanol strategy has
higher capital cost, it demonstrates lower total annualized cost than
Strategy II. A recommendation concerning Strategy II vs. Strategy III
should be based on a comparison of the benefits of the earlier air
quality improvements (Strategy II) to the lesser total annualized cost
(Strategy III). A quantitative analysis of this problem is not possible
within the level of effort allocated to this study. However, by a cursory
analysis of the problem, we find a distinct preference for Strategy III.
Strategy III has appeal because of substantial side benefits for
national energy problems. Further, Strategy III is preferable because it
5-2
-------
TABLE 5-1
SUMMARY OF AIR QUALITY IMPACTS, CONTROL COSTS, AND
IMPLEMENTATION PROBLEMS ASSOCIATED WITH THE
ALTERNATIVE CONTROL STRATEGIES
Present Control Emission Forecast
EPA Oxidant Plan Emission Forecast
Control Strategy I: A Reasonable/
Implementable Scenario for 1977
and 1980. (The Desulfurization
Scenario)
Control Strategy II: Maximal
Technological Control by 1977
Control Strategy III: A De-
layed Scenario for 1980 based
on Methanol Conversion
;ontrol Strategy IV: A Drastic
Source Relocation/VMT Reduction
Strategy to Attain the Pri-
mary Standard by 1980
AIR QUALITY FORECAST
Average AAM at the 4-
worst stations (Chi no,
Azusa, Riverside, & Lennox)
1972 Level = 169 ug/m3
1977
187 >ig/m3
1T9 ug/m3
117jjg/m3
110/jg/m3
152;jg/m3
110 ug/m3
1980
180 ug/m3
174 pg/m3
112 fjg/m3
108 ug/m
108 /jg/m3
72 ug/m3
Number of stations which
attain the primary national
standard target level. (Out
of the 8 sites studied)
1972 Level = 0
1977
0
0
2
2
0
2
1980
0
0
2
2 .
2
8
CONTROL COSTSb
Initial
Capital
Cost
(Millions)
$ 896
$1211
$1650
Undeter-
mined0
Total
Operation
Cost
(Millions/year
$ 119
$ 206
$ 47
Undeter-
mined
Total
Annual 1 zed
Cost
(Millions/year)
$ 226
$ 367
$ 235
Undeter-
minedc
IMPLEMENTATION DIFFICULTIES
Relative level of Implementation
Problems on a scale of 1 to 10.
1 = Difficult
10 = Extremely Difficult
1
2
2
10
01
I
00
a. These eight sites are not typical locations but rather are among those with the highest particulate levels.
b. These costs are in addition to the present controls and the EPA oxidant plan which are assumed as part of each strategy.
c. These costs would be at least as great as Strategy II which is included in Strategy IV. They might actually be orders
of magnitude more.
-------
is the best long run plan. Particulate air pollution will be a long term
problem for the Los Angeles Region, and we consider long term strategies
to have distinct advantages over shorter term plans.
To summarize, the reasonable/implementable and the delayed methanol
conversion scenarios are the preferred plans among the four strategies
formulated here. Choosing between these two strategies is difficult. The
two plans result in nearly the same total annualized cost. Strategy I
leads to significantly better air quality in 1977 but to slightly worse
air quality in 1980. Strategy III requires more capital investment and
involves considerably more implementation obstacles. However, as noted
above, Strategy III has beneficial side-effects for the national energy
problem and is very attractive on a long-tenti basis. All in all, we find
a slight preference for Strategy III because of the long-term advantages.
The major factor which is of concern with Strategy III is the implementa-
tion problem which will be encountered, (see Section 4.3.3).
Several of the control measures in Strategies I and III are identical,
(See Tables 4-1 and 4-9). For these measures we recommend that steps be
taken for actual implementation. These steps should include an in-depth
analysis of each measure to prepare for possible engineering, administrative,
or legal problems. For the areas where Strategies I and III diverge,
(essentially fuel desulfurization plus stack controls vs. methanol conver-
sion), it is recommended that further comparative analysis be done,
especially in the area of implementation obstacles. This will allow a more
confident choice to be made between the two alternatives. Steps can then be
taken to implement the appropriate strategy.
5-4
-------
A control policy based on either Strategy I or Strategy III should
also include some non-technological controls such as growth restrictions,
energy conservation incentives, transportation measures, and possibly
some relocation. These administrative controls will be particularly impor-
tant in the long run. It was not possible in this study to perform a
quantitative analysis of non-technological controls. Strategy IV indicated
the overall level of administrative control that would be needed to attain
the air quality standards by 1980. However, this very severe level of
control would require extensive source relocation and gas rationing. We
recommend that more moderate forms of administrative control be documented
and that these be included in a comprehensive air quality policy.
It should be remembered that the above control strategies have been
formulated and evaluated for the 4-County Area of the Metropolitan
Los Angeles Region. The remainder of the Los Angeles Region, Ventura and
Santa Barbara Counties, experiences a much less severe particulate air
pollution problem. Presently, the suspended particulate levels in Ventura
and Santa Barbara Counties are just above the national primary standard.
Either Strategy I or Strategy III would attain the national primary
standard (and possibly the national secondary standard) when applied to the
Ventura/Santa Barbara area. However, since the origin of the particulate
problem in these two counties is apparently different, (mineral industries
and agriculture are much more important than in the 4^County Area), it is
recommended that a separate examination be made of the particulate control
problem for Ventura and Santa Barbara. It should be possible to pick a
5-5
-------
different strategy for Ventura and Santa Barbara that would involve lower
costs and less implementation problems. The examination of control
strategies for these counties might best be carried out by local control
agencies who are familiar with the important stationary source problems.
In order to be consistent with the present form of the national air
quality standards for suspended particulates, the air quality evaluation
of the above strategies has been done only on the basis of total mass
o
concentration of suspended particulates, (jjg/m ). As noted in Section
1.2, (Limitations in the Scope of the Study), the chemical composition of
suspended particulates. is very important to health effects. In the future,
air quality standards may be expected for certain aerosol constituents.
Sulfate aerosol is of particular concern in this respect. Since the air
quality model used here inherently includes calculations of sulfate levels,
it may be useful to indicate the effect of the two recommended strategies
on sulfate levels. Table 5-2 provides estimates of sulfate air quality
for each of the strategies. These results should be interoreted with
caution. As noted in Section 2.3.2, the air quality model tends to be
especially uncertain when used to predict individual secondary aerosol
components such as sulfates, nitrates, and secondary organics.
Section 1.2 also noted that particle size distribution is important
to health and visibility considerations. Particles in the .1 to 1 micron
range are especially significant. In this regard, we can add an optimistic
note. The strategies here have been formulated for man-made primary
suspended particulates (less than 10 microns in size) and for man-made
sources of secondary aerosol. These man-made sources are the major con-
tributors of aerosol in the smaller size range, (<1 micron). The greatest
5-6
-------
TABLE 5-2 SULFATE AIR QUALITY IMPACT OF
THE RECOMMENDED STRATEGIES3
(>ig/m3 - AAM)
Locati on
Lennox
Long Beach
Central Los Angeles
Anaheim
Azusa
Ontario
Riverside
Chino
Esti-
mated
sof
Back-
ground
4
4
4
4
4
4
4
4
Expect-
ed 197;
so:
Levels
13
11
14
9
15
10
12
22
Strategy I
S0| Levels
1977 1980
8 V
7 h'
9
6 h
9 h,.
7
8
13
6
5 h
6
5
6
5
5 *
8 *
Strategy III
S0| Levels
1977 1980
12 h
10 %
13 %
8 ^.
14
9 %
11 %
22 %
5
4 *
5
4 *
5
4'V
5
5 h
b.
These results have been computed using the linear S04/S02 model
outlined in Section 2.3.2. As noted there and in Support Document
#3, the linear model probably tends to underestimate resulting sulfate
levels. As indicated in the support document, the calculated controlled
values in this table are likely about 1 jug/m^ low, with the maximal
error possibly as much as 3 A-ig/m3. The uncertainties in the linear
model should be kept in mind in interpreting these results.
The calculation for Chino is performed in a specialized way as out-
lined in Section 2.3.3. The local Kaiser/Edison contribution is
computed separately.
5-7
-------
portion of the natural aerosol, Csea salt and soil dust), occurs pre-
dominately in the larger size range (<1 micron), [93]. When a given
percent of control is suspended particulate air quality is indicated in
this report, this control tends to occur among the sources of the smaller
particles. The relative reduction in mass loading of the smaller par-
ticles will likely be greater than the relative reduction in total mass
loading. Thus, one would expect more improvement in visibility and
health than indicated by the calculated improvements in total mass loading.
5.2 CONCLUSIONS AND RECOMMENDATIONS RESULTING FROM THE TECHNICAL SUPPORT
ANALYSES
The principal goal of this study was to investigate control strategies
for approaching and achieving the National Ambient Air Quality Standards
for suspended particulates in the Metropolitan Los Angeles Region. In
order to perform a systematic investigation, four major technical support
analyses were conducted. These were (1) an analysis of particulate air
monitoring procedures and a characterization of present air quality
levels in the Los Angeles Region, (2) a compilation of emission inventories
and projections for both primary particulates and gaseous precursors of
secondary particulates, (3) the development of a methodology to translate
changes in emission levels into changes in air quality, and (4) an identifi-
cation and evaluation of alternative emission control measures for major
sources of both primary particulates and gaseous precursors of secondary
aerosol. These analyses are described in detail in Technical Support
Documents #l-#4. Chapters 2 and 3 of this report are condensed versions
of the support documents.
5-8
-------
This section serves to summarize the major conclusions and recommenda-
tions which resulted from the technical support analyses. This summary
includes some discussion of analytical limitations and of needs for future
work. Each of the four technical areas is treated in turn below.
Analysis of Air Monitoring Data
Conclusions:
Hi-Vol filters generally'provide a very efficient means of
entrapping samples of suspended particulate matter. However,
samples are not always fully representative of ambient conditions
due to loss of volatile liquids (such as water or organics) and/or
gain of adsorbed gaseous pollutants(such as S02 or NC^). Hi-Vol
data do not provide information on particle size distribution.
Specific monitoring practices can significantly affect Hi-Vol
accuracy. Substantially different practices can produce dis-
crepancies on the order of 20%. The reproducibility of individual
Hi-Vol measurements using equivalent procedures is around 5% under
field conditions.
The APCD, NASN, and CHESS monitoring programs generally follow the
same sampling guidelines. However, deviations exist in certain
specific practices such as-sampling frequency, calibration pro-
cedures, flqw rate, analysts delay time, and location. In some
cases, these deviations are enough to cause significant differences
in measured values.
The 6 CHESS sites in the Los Angeles Region are located in quiet
suburban areas. Measurements from CHESS monitors are generally
around 20-40% lower than those from APCD and NASN sites which tend
to be in prime exposure urban areas.
The western part of the basin, near the coast, tends to experience
the highest Hi-Vol levels during the winter season. In the eastern
part of the basin, the summer/fall period tends to yield the highest
Hi-Vol readings. These findings appear to be consistent with the
hypothesis that primary particulate (directly emitted) is relatively
more important in the western basin while secondary particulate
(formed by atmospheric reactions) is relatively more important
in the eastern areas.
The federal secondary air quality standards are exceeded at all
monitoring sites which were analyzed. Ventura and Santa Barbara
Counties as well as the coastal areas of Los Angeles and Orange
Counties typically yield Hi-Vol levels at just about the federal
primary standards. Riverside and San Bernardino Counties and the
inland areas of Los Angeles and Orange Counties yeild Hi-Vol values
up to more than twice the federal primary standards.
5-9
-------
In the inland areas of greatest participate pollution, no general
pattern can be discerned in Hi-Vol measurements with the present
level of spatial resolution. The location of each monitoring
site with respect to local sources appears to be important; this
effect produces fluctuations so that no general pattern emerges.
Recommendati ons:
It would be useful to perform experimental studies to gain further
information on the differences between Hi-Vol measured particulates
and actual ambient particulates. These studies should focus on
quantifying the loss of water and volatile organics and the gain
of adsorbed gaseous pollutants under actual field conditions.
A further standardization of Hi-Vol procedures among various moni-
toring programs is recommended. The establishment of guidelines
for site location with respect to local sources is particularly
important. This standardization could afford more meaningful
comparisons of data from alternative monitoring programs.
The establishment of an ongoing program of data analysis would
allow better use to be made of the considerable quantities of
Hi-Vol data being generated in the Los Angeles Region. Such a
program should continually examine trends in total suspended
particulate levels and in specific aerosol constituents and should
compare these results with the expected impact of source growth
and emission control policy.
0 For the purpose of control strategy formulation, at least three
general sub-areas have been identified, each with different maximal
Hi-Vol levels (the maximum among the monitoring sites in those
areas). These are A. Ventura and Santa Barbara Counties (presently
just above the national primary standard), B. The 4 County Area
except Area C (presently at about twice the national primary
standard), and C. The Western San Bernardino County Hot-Spot
(presently at about three times the national primary standard).
The formulation and evaluation of control strategies should make
distinctions among these three areas.
Emission Inventories and Projections
Conclusions:
Numerous alternative data sources are available for compiling the
1972 base year inventory of primary suspended particulates, SC^,
NOX, and RHC for the Los Angeles Region. Conflict often exists
among the varous data sources; this is an indication of the un-
certainties in emission data. Presently, the most appropriate
way to construct an emission inventory for implementation planning
is to use many sources of data, picking the most reliable sources
for each inventory category.
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t Data are not available for compiling an RHC inventory based on the
aerasol forming potential of organic gases. For the purposes of
this study, an RHC inventory based on oxidant reactivity seems more
appropriate than a total hydrocarbon inventory.
The size distribution of particulate emissions from various sources
is not well documented. However, estimates of the fraction of
particles below VQ microns for various sources are available so that
suspended particulate emissions can be distinguished in an approxi-
mate way from total particulate emissions.
Motor vehicles are the major source of RHC and NOX emissions in the
1972 base year inventory for the Los Angeles Region. Motor vehicles
and stationary source fuel combustion account for most of the
suspended particulate emissions. Stationary fuel combustion, the
chemical industry, petroleum refineries, and motor vehicles are
respectively the most important sources of S02.
The forecasted substitution of fuel oil for natural gas in many
stationary combustion sources and the scheduled controls for motor
vehicles are the two most significant factors affecting emission
projections for 1977 and 1980 in the Los Angeles Region. Due to
the increased use of fuel oil, total emissions of suspended parti-
culates, S02, and NOX will increase from 1972 to 1977 with present
control policies. The motor vehicle control program will signifi-
cantly reduce regional RHC emissions in 1977 and 1980; it will also
reverse the upward trend in NOX emissions, (leading to a decrease
between 1977 and 1980). Stationary combustion will be the largest
single source of suspended particulates and S02 in 1980 and will
nearly equal motor vehicles as an NOX contributor.
t The EPA oxidant implementation plan results in significantly lower
RHC emissions than present control policy. The EPA oxidant plan
also achieves very slight reductions in particulate and SOg
emissions. However, the catalytic converter retrofit called for by
the EPA plan, (as well as the new car catalytic converters), will
result in the emission of sulfuric acid mist from motor vehicles.
The latter can be controlled by desulfurization of motor fuels or
by S02 scrubber/particulate trap retrofits.
Large scale emission density maps reveal that RHC, NOX, and (to
some extent) particulate emissions are distributed in a way
similar to population and motor vehicle traffic within the
Los Angeles Region. An emission density map for SO? indicates the
importance of very localized sources for that pollutant.
Recommendations:
Efforts to update emission information for both mobile and station-
ary sources should be supported. Further documentation is needed
to reduce uncertainties concerning both source growth -rates and
source emission factors.
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0 Of special importance to particulate air quality studies is
the need for RHC emission inventories based on the aerosol form-
ing reactivity of organic gases. Also of importance is in-
formation on the size distribution of particulates from various
sources. Further effort should be made to generate data perti-
nent to these two issues.
The severe air pollution problem in the Los Angeles Region will
be significantly aggravated by the forecasted substitution of
fuel oil for natural gas in many stationary combustion sources.
It is recommended that national allocation of clean fuels,
such as natural gas, be performed with strong consideration
given to air quality impacts in various regions.
The Relationship Between Emissions and Ambient Air Quality
Conclusions:
t In order to construct a systematic relationship between sus-
pended particulate levels and emissions of primary particulates,
S02» NOX, and RHC, two separate analyses must be performed. The
first is to characterize the origins (e.g., background, non-
background primary, non-background sulfate, etc.) of suspended
particulate levels at various locations. The second is to de-
termine the dependence of each origin category on emission
levels.
Existing aerosol composition data (from the county APCD's, NASN,
and other monitoring programs) are sufficient to support an
approximate aerosol origin characterization for annual arithmetic
means (AAM'S) at twelve locations in the Los Angeles Region.
Existing data are not sufficient to characterize aerosol origins
on episode days. The latter result may not be a severe handi-
cap to control policy formulation since it appears that the
annual national standards for particulates are more restrictive
than the 24 hour max. national standards in the Los Angeles
Region.
Existing data indicate that background (non-controllable) particu-
late levels are about 30-40 ug/m3 AAM in the coastal areas of
the Los Angeles Region. Background aerosol levels appear to
increase with distance inland to about 45-60 jug/m3AAM in the
eastern-inland parts of the region. The existence of significant
background levels limits the air quality effectiveness of emis-
sion controls in the Los Angeles Region.
Non-background primary particulate contributions generally tend
to be highest in the coastal and central-valley portions of the
Los Angeles Region. The one exception involves the very high
primary contributions estimated for the Western San Bernardino
County Hot-Spot (Chino-Rialto) which is apparently affected by
the Kaiser/Edison complex. Sulfate levels tendgto be uniformly
distributed over the basin at around 10-15 jjg/m AAM, (again the
Hot-Spot is an exception). Measured nitrate and estimated
5-12
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secondary organic levels tend to increase considerably with
distance inland. The above spatial trends appear to be con-
sistent with known aspects of source distribution, meteorology,
and atmospheric chemistry.
For the purposes of this study, the linear rollback formula
appears to be generally adequate for relating primary suspended
particulate emissions to non-background primary aerosol levels.
In order to assess air quality changes for the special case of
the Western San Bernardino County Hot-Spot, a modification of
the linear rollback approach must be made.
Considerable uncertainty surrounds the relationship between
non-background sulfate air quality and S02 emissions. However,
theoretical analysis and empirial data both suggest a slightly
less than linear dependence. At low SCL levels, sulfate yield
appears to increase linearly with S02 input. At higher S02
levels, the sulfate yield tends to level off. For the purpose
of this study, (the prediction of total suspended particulate
levels), it appears sufficient to assume a linear relationship.
0 Very little is known concerning the dependence of nitrate
levels on NO emissions and the dependence of secondary organic
levels on RHC emissions. In this study a simple linear form
is assumed for each relationship. The main justification is
that there is no evidence to support the use of any specific
nonlinear relationship.
Recommendations:
0 In order to improve the aerosol origin estimates, more com-
prehensive data are needed on particulate chemical composition.
Specifically, it is recommended that further sodium and aluminum
data be taken to verify the sea salt and soil dust levels cal-
culated here. Also, it would be very useful to devise and apply
a method for measuring secondary organic particulate levels.
Existing data on ambient organic aerosol, (benzene or cyclo-
hexane solubles), are essentially only measures of primary organic
contributions.
0 Further research effort should be allocated to determining the
the dependence of secondary aerosol levels on gaseous precursor
emissions. Much of the research to date has been directed to-
ward identifying the reaction mechanisms and understanding the
physico-chemical processes. This work should be continued since it
supplies a scientific base for explaining the relationship.
However, it may be possible to obtain reasonable answers in a
shorter time by emphasizing an empirical approach. Ambient and
experimental measurements of NO (or S02) input vs. nitrate
(or sulfate) yield may be able to supply a relationship that
is adequate for present planning purposes.
5-13
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Evaluation of Alternative Emission Control Measures
Conculsions:
Eight process categories are the major candidates for control in
the Los Angeles Region. These are stationary source fuel com-
bustion, motor vehicles, the petroleum industry, aircraft, the
chemical industry, metallurgical processes, organic solvent use,
and the mineral industry. Together these categories account
for more than 97 percent of the emissions of primary particulates,
S02, NOX, and RHC in the Los Angeles Region. Especially signifi-
cant are the fuel combustion, motor vehicle, petroleum, and air-
craft categories.
The federal and state motor vehicle control programs and the
county APCD stationary source control programs have achieved
substantial overall control for primary particulates and gaseous
- precursors of secondary aerosol in the Los Angeles Region.
However, additional control options can be identified to bring
significant further reductions in emissions.
The most significant additional control alternatives for primary
suspended particulates in the Los Angeles Region are motor
vehicle particulate traps, fabric filters, and electrostatic
precipitators. For S02, the major options are desulfufization
of petroleum products to very low sulfur levels, S02 removal
processes for exit gases, and alternative fuels. For NOx
control, various modifications of combustion processes and
alternative fuels are the principal control possibilities.
No major new options for RHC control, other than those con-
tained in the EPA oxidant implementation plan, have been identified.
Application of the most effective control options which have been
identified will attain overall reductions of 59 percent, 86 per-
cent, and 22 percent (for primary suspended particulates, S02 and
NOX respectively) from projected 1977 levels. Since emissions of
each pollutant are forecasted to increase from 1972 to 1977, the
overall reductions in 1977 from the 1972 levels are only 49 per-
cent, 83 percent, and 6 percent respectively. The EPA oxidant
plan will achieve a 51 percent reduction in RHC levels from
1972 to 1977.
t The total annualized cost associated with a major new control
program to achieve substantial emission reductions such as that noted
above would be around $300 million per year. The initial capital
cost would be around $1 billion. These costs would be in addi-
tion to the costs of present controls and the costs associated
with the EPA oxidant plan.
The various control measures for each pollutant demonstrate a wide
range of cost-effectiveness. Most of the suspended particulate
controls yield cost effectiveness ratios around $1,000 to $7,000
per ton. The majority of the S02 controls considered here had
cost-effectiveness values of around $500 = $1500 per ton. Most
5-14
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NOx measures tended to demonstrate ratios of around $500 -
$1200 per ton controlled.
V t
Many of the potential control measures will entail signifi-
cant implementation difficulties. These will include problems of
technical development, engineering application, enforcement,
and administration.
Recommendations:
As control strategy planning efforts proceed, more in-depth
analysis should be performed on the effectiveness and cost of
the control measures studied in this report. Due to limitations
on time and level, of effort, the present study estimated control
efficiency and costs on a simplified basis, aggregating over many
emission sources in a given process category. The cost and
effectiveness of the measures will likely vary substantially among
individual sources within a given process category. Some of these
variations can have significant implications for control policy.
As part of the implementation procedure, proposed control measures
should undergo an intensive evaluation as to real applicability.
This evaluation should be carried out by a task force of in-
dustrial, academic, and governmental experts who would consider
the specific engineering, enforcement, and legal problems
involved with the control measure. A carefully planned and
executed implementation procedure should help to reduce technical
difficulties as well as public and private resistance.
Further attention should be given to a long tern view of the
various control measures. A strategy based on long run considerations
may be considerably different from one designed to achieve short
run control. Short run controls should be evaluated as to their
compatibility with likely long run controls.
5-15
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BLANK PAGE
5-16
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REFERENCES
1. Crawford, K. W. and Tr1 join's, J. C., "An Implementation Plan for Sus-
pended Participate Matter in the Los Angeles Region, Technical Support
Document #1: Analysis of Air Monitoring Data,'-1 prepared-for. the Environ-
mental Protection Agency under Contract #68-02-1384, TRW Environmental
Services, 1975.
2. Tan, R. L. and Wada, R. Y., "An Implementation .Planrfor Suspended
Particulate Matter in the Los Angeles Region, Technical Support Docu-
ment #2: Emission Inventories and Projections/' prepared for the
Environmental Protection Agency under Contract #68-02-1384, TRW
Environmental Services, 1975.
3. Trijonis, 0. C., "An Implementation Plan for Suspended Particulate
Matter in the Los Angeles Region, Technical Support Document #3:
Air Quality-Emission level Relationship." prepared for the Environ-
mental Protection Agency uWd₯r~contract #68-02-1384, TRW Environmental
Services, 1975.
4. Richard, 6., "An Implementation.Plan for .Suspended Particulate Matter
in the Los Angeles Region, Technical Support Document #4: Alterna-
tive Emission Control Measures," prepared for the Environmental Pro-
tection Agency under Contract #68-02-1384, TRW Environmental Services,
1975.
5. Federal Register, Volume 36, Number 84, Part II, 30 April 1971.
6. Jutze, G. A. and Foster, K. E., "Recommended Standard Method for Atmo-:
spheric Sampling of Fine Particulate Matter by Filter-Media/High
Volume Sampling," Air Pollution Control Association J., 17 (1), p 17
(1967).
7. Methods of Air Sampling and Analysis, Intersociety Committee, American
Public Health Association, Inc., (1972).
8. Tierney, G. P. and Conner, W. D., "Hygroscopic Effects on Weight
Determination of Particles Collected on Glass Fiber Filbers," Am.
Industrial Hygiene Assoc. J.. Vol. 28 p 363 (1967).
9. Wadley, Margil, Chemist, LA APCD, Personal Communication, April 1974.
10. Hidy, G. et al., "Characterization of Aerosols in California (ACHEX),
Interim Report, Phase I," 'Rockwell International Science Center,
California ARB Contract #358 (1974).
11. "Guideline for the Development of a Quality Assurance Program for
High-Volume Sampling," U.S. Environmental Protection Agency R4-73-
028b, June 1973.
R-l
-------
12. Mueller, Peter, Region IX, EPA, Personal Communication, March 1974.
13. Robson, C. D. and Foster, K. E., "Evaluation of Air Particulate Samp-
ling Equipment," Am. Ind. Hygiene Assoc. J.. 23, p 404-410 (1962).
14. Lee, R. E. et al, "Evaluation of Methods of Measuring Suspended Parti-
culates in the Atmosphere," 162nd National Meeting of the American
Chemical Society, Washington, D.C., Dec. 12-17, 1971.
15. Clements, H. A., et al, "Reproducibility of the Hi-Vol Sampling Method
Under Field Conditions," J. Air Pollution Control Assoc.. Vol. 22,
No. 12, p 955 (1972). [
16. Faora, R., "Collaborative Study of the Reference Method for Determina-
tion of Suspended Particulates in the Atmosphere," U.S. Environmental
Protection Agency, APTD-0302, PB 205-892.
17. Cohen, A. L., et al, "Dependence of Hi-Vol Measurements on Airflow
Rate," E,nvironmental Science and Technology, Vol. 7, No. 1, p 61 (1973).
18. McKee, C. H., et al, "Collaboration Testing of Methods to Measure
Air Pollutants," J. Air Pollution Control Association, Vol. 22, No. 5
p 342 (1972). .
19. Holmes, John, Chemist with California Air Resources Board, Personal
Communication, April 1974.
20. Grosjean, Daniel, Caltech, Post Doctoral Fellow, Personal Communication,
April 1974.
21. Thompson, R., University of California Riverside, Personal Communica-
tion, April 1974.
22. Hartledge, Thomas, Environmental Protection Agency, Personal Communi-
cation, April 1974.
23. State of California, The Resources Agency, Air Resources Board, "Air
Pollution Control in California 1971," January 1971.
24. TRW Inc., "Transportation Control Strategy Development for the Metro-
politan Los Angeles Region," January 1973.
25. TRW Inc.,"Episode Contingency Plan Development for the Metropolitan Los
Angeles Air Quality Control Region," December 1973.
26. EPA, "Compilation of Air Pollution Emission Factors," February 1973.
27. Private communication, John Nevitt, Los Angeles County APCD.
28. Habibi, K., "Characterization of Particulate Matter in Vehicle Exhaust,"
Environmental Science and Technology, Vol. 7, No. 3, March 1973.
R-2
-------
29. Automotive Environmental Systems, Inc., "Uncontrolled Vehicle Emis-
sion Study," Report to the California State Air Resources Board,
October 30, 1973.
30. Pierson, W. R. and Brachaczek, W. W., "Airborne Particula^e Debris
from Rubber Tires," preliminary draft, presented at the American
Chemical Society Rubber Division Symposium on Ecology, May 7-10,
Toronto, Ontario, Canada.
31. Wells Fargo Bank, "Moving Ahead - Wells Fargo Looks at Southern
California," 1973.
32. "Final Report - Southern California Regional Aviation Systems Study,"
prepared for the Southern California Association of Governments,
Aviation Study Authority by System Development Corporation/William
L. Pereira Associates.
33. Private communication, Morris Goldberg, EPA, Region IX.
34. EPA, "Population and Economic Activity in the United States and
Standard Metropolitan Statistical Areas," 1972.
35. Private communication, Bart Sokolow, Los Angeles City Department of
Water and Power.
36. "1973 California Gas Report."
37. Campion, R. J., et al, "Measurement of Vehicle Particulate Emis-
sions," Society of Automotive Engineers, Automotive Engineering
Congress, February 25 - March 1, 1974, Detroit, Michigan.
38. Federal Register, Vol. 38, No. 217, Part II, November 12, 1973.
39. County of Los Angeles, Air Pollution Control District Rules and
Regulations.
40. California Air Resources Board, "California Air Quality Data,"
Quarterly Reports, 1972-1973.
41. Gordon, R. J. and Bryan, R. J., "Ammonium Nitrate in Airborne Parti-
cles in Los Angeles," Environmental Science and Technology, Vol. 7,
July 1973.
42. Lundgren, D. A., "Atmospheric Aerosol Composition and Concentration
as a Function of Particle Size and of Time," Journal of the Air
Pollution Control Association. Vol. 20, No. 9, September 1970.
43. Hidy, G. M., et al., "Characterization of Aerosols.in California,
Interim Report for Phase I," prepared, for.the. California.Air Resources
Board by Rockwell International under ARB Contract No. 358, December
1973.
R-3
-------
44. Los Angeles County Air Pollution Control District, Profile in Air
Pollution Control. 1971.
45. Altshuller, A. P., "Atmospheric Sulfur Dioxide and Sulfate," Environ-
mental Science and Technology. Vol. 7, No. 8, August 1973.
46. Hilovsky, R., San Bernardino County AOCD, personal communication,
September 1974.
47. National Air Pollution Control Administration, "Control Techniques
for Particulate Air Pollutants," publication of U.S. Department of
Health Education and Welfare, January 1969.
48. "Basic Technology," Section IV Air Pollution Control, Desk Book Issue,
Chemical Engineering, April 27, 1970.
49. Christensen, R., Chevron Research Company, "Low Sulfur Products from
Middle East Crudes," National Petroleum Refiners Association, AM-73-
38, April 1973.
50. Slack, A., Division of Chemical Development, Tennessee Valley Author-
ity, "Removing SO? from Stack Gases," Environmental Science and Tech-
nology, February 1973.
51. Olds, F., "S02 & NOX," Power Engineering. August 1973.
52. Reed, T. and Lerner, R., "Methanol: A Versatile Fuel for Immediate
Use," Science. December 1973.
53. "Outlook Bright for Methyl-Fuel," Environmental Science and Technology,
November 1973.
54. TRW Transportation and Environmental Operations, "Development of a
Sample Air Quality Maintenance Plan for San Diego," prepared for
Environmental Protection Agency, September 13, 1974.
55. TRW Transportation and Environmental Operations, "Transportation
Control Strategy Development for the Metropolitan Los Angeles
Region," prepared for Environmental Protection Agency, January 1973.
56. Rand Corporation, "San Diego Clean Air Project," R-1366-SD Appendix
4, December 1973.
57. Hprwitz, H and Kuhrtz, S., Environmental Protection Agency,
"transportation Controls to Reduce Automobile Use and Improve Air
Quality in Cities," November 1974.
58. Los Angeles County Air Pollution Control District, Air Emissions
Computer Inventory File, obtained by purchase from the District.
R-4
-------
59. Bell, A., "Combustion Control For Elimination of Nitric Oxide Emis-
sions from Fossil Fuel Power Plants," presented at 13th International
Symposium on Combustion, University of Utah, Salt Lake City, Utah,
March 1970.
60. ESSO Research and Engineering Company, "Systems Study Control Methods
for Stationary Sources," Volume II, prepared for National Air Pollu-
tion Control Association, November 1969.
61. HEW (Department of Health, Education and Welfare), "Control Techni-
ques for Nitrogen Oxide Emissions from Stationary Sources," Report
AP-67, March 1970.
62. Downing, P. and Stoddard, L., "Benefit/Cost Analysis of Air Pollution
Control Devices for Used Cars," Project Clean Air Research Reports,
Volume 3, (Riverside, California: University of California, 1970).
63. Trijonis, John, "An Economic Air Pollution Control Model Application:
Photochemical Smog in Los Angeles County in 1975, Thesis at the
California Institute of Technology, May 1972.
64. Personal communication with Arthur D. Little, Inc., New York.
65. Air Pollution Control District of Los Angeles, Report to the Los
Angeles County Energy Commission on "The Feasibility of Burning
Combinations of Natural Gas and High Sulfur Fuel Oil," May 1974.
66. Air Pollution Control District of Los Angeles, "Air Pollution Engi-
neering Manual," U.S. Environmental Protection Agency Publication
AP-40, May 1973.
67. Personal communication with Chevron Research, San Francisco, California.
68. California Gas Report, 1973.
69. Environmental Protection Agency, "Aircraft Emissions: Impact on Air
Quality and Feasibility of Control."
70. Environmental Protection Agency, "Compilation of Air Pollutant Emis-
sion Factors, AP-42, Second Edition, April 1973.
71. Los Angeles Air Pollution Control District, "Study of Jet Aircraft
Emissions and Air Quality in the Vicinity of the Los Angeles Inter-
national Airport, April 1971.
72. Personal communication with Dick Munt, Environmental Protection
Agency, Ann Arbor, Michigan.
73. Jones, Kay; Sampson, Robert; Holmes, John, Environmental Protection
Agency, "The Federal Aircraft Emissions Control Program: Standards
and Their Basis," Journal of the Air Pollution Control Association.
January 1974.
*
R-5
-------
74. Environmental Protection Agency, "Air Programs: Approval and Promul-
gation of Implementation Plans," California Transportation Control
Plan, Federal Register, December 12, 1973.
75. Beltzer, Morton; Campion, Raymond; Peterson, William, ESSO Research
and Engineering Company, "Measurement of Vehicle Particulate Emis-
sions," Society of Automotive Engineers, 740286, February 25-March 1,
1974.
76. Environmental Protection Agency, "Regulations on Fuels and Fuel
Additives," Environmental Reporter 121:0801, 1973.
77. Personal communication with Chevron Research Company, San Francisco,
California.
78. United States Department of Commerce, "Automotive Fuels and Air
Pollution," a Report of the Panel on'Automotive Fuels and Air Pollu-
tion, March 1971.
79. Haas, G., Lenane, D., Brandt, M., Ethyl Corporation, "Composition,
Size and Control of Automotive Exhaust Particulates," Journal of
the Air Pollution Control Association. January 1972.
80. Personal communication with Atlantic Richfield Corporation, Los
Angeles, California.
81. Technical Advisory Committee to the California State Air Resources
Board, "A Rational Program for Control of Lead in Motor Gasoline,"
March 1970.
82. Sorem, S. S., "Automotive Fuels and Air Pollution," statement by
Shell Oil Company to the Arizona Board of Health, November 20, 1970.
83. Lenane, Dennis, Ethyl Corporation Research and Development Depart-
ment, Letter of Data Transmittal to J. Sommers, Environmental Pro-
tection Agency, June 7, 1973.
84. Personal communication with Ethyl Corporation Research and Develop-
ment, Ferndale, Michigan.
85. Aerospace Corporation, Final Report: "An Assessment of the Effects
of Lead Additives in Gasoline on Emission Control Systems Which
Might be Used to Meet the 1975-76 Motor Vehicle Emission Standards,"
distributed by NTIS, U.S. Department of Commerce, November 1971.
86. Atomics International, North American Rockwell, "Evaluation of a
Device to Remove Lead and Particulates from Automobile Exhaust,"
a technical proposal to the Division of Motor Vehicle Research and
Development, National Air Pollution Control Administration, AI-70-51P,
August 1970.
87. Personal communication with Atomics International, Canoga Park,
California.
R-6
-------
88. Personal communication with Binks Company, Los Angeles, and
DeVilbiss, Los Angeles.
89. Air Pollution Control District, County of Los Angeles, "Profile of
Air Pollution Control," 1971.
90. Los Angeles County Air Pollution Control District, "Air Pollution
Engineering Manual," Document AP-40, Environmental Protection Agency,
May 1973.
91. Personal communication with Los Angeles County Air Pollution Control
District.
92. Printout of Computer Emission Inventory File, developed by Los
Angeles County Air Pollution Control District.
93. Gartrell, G., and Friedlander, S. K., "Relating Particulate Pollution
to sources: The 1972 California Aerosol Characterization Study,"
Working Paper, W. M. Keck Laboratory of Environmental Engineering,
Caltech, Pasadena, California.
R-7
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