CHAPTER 1

INTRODUCTION

Purpose

Constraints in Achieving Standards

Control Efforts

1994 Air Quality Management Plan

1997 AQMP Revision

Format of This Document
Chapter 1 Introduction

1 - 1

PURPOSE

The purpose of the 1997 Revision to the Air Quality Management Plan (AQMP or Plan) 

for the South Coast Air Basin (Basin) and those portions of the Mojave Desert Air Basin 

and Salton Sea Air Basin under the South Coast Air Quality Management District 

(District) jurisdiction, is to set forth a comprehensive program that will lead these areas 

into compliance with all federal and state air quality planning requirements. Specifically, 

the 1997 AQMP Revision is designed to satisfy: 1) the State Implementation Plan 

requirements under Title I of the federal Clean Air Act (CAA) and 2) the California 

Clean Air Act (CCAA). These federal and state requirements are summarized briefly 

later in this chapter.

The 1997 AQMP sets forth programs which require the cooperation of all levels of 

government: local, regional, state, and federal. Each level is represented in the Plan by 

the appropriate agency or jurisdiction that has the authority over specific emissions 

sources. Accordingly, each agency or jurisdiction is assigned specific planning and 

implementation responsibilities.

At the federal level, the U.S. Environmental Protection Agency (EPA) is charged with 

regulation of on-road motor vehicle standards; trains, airplanes, and ships; non-road 

engines; and off-shore oil development. The Air Resources Board (ARB), representing 

the state level, also oversees on-road vehicle emission standards, fuel specifications, 

some off-road sources and consumer product standards. At the regional level, the 

District is responsible for stationary sources and some mobile sources. In addition, the 

District has lead responsibility for the development and adoption of the Plan. Lastly, at 

the local level, Associations of Governments have a dual role of leader and coordinator. 

In their leadership role, they, in cooperation with local jurisdictions and subregional 

associations, develop strategies for these jurisdictions to implement; as a coordinator, 

they facilitate the implementation of these strategies. For the South Coast Air Basin, the 

Southern California Association of Governments is the District’s major partner in the 

preparation of the AQMP. Interagency commitment and cooperation are the keys to 

success of the AQMP. 

Since air pollution physically transcends city and county boundaries, it is a regional 

problem. No one agency can design or implement the Plan alone, and the strategies in 

the Plan reflect this fact.
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CONSTRAINTS IN ACHIEVING STANDARDS 

The District is faced with a number of constraints or confounding circumstances to 

achieving clean air. These include the physical and meteorological setting, the large 

pollutant emissions burden of the Basin, and the rapid population growth of the area.

Setting

The South Coast Air Quality Management District has jurisdiction over approximately 

12,000 square miles consisting of the four-county South Coast Air Basin and the Los 

Angeles county and Riverside county portions of what used to be under state 

classification the Southeast Desert Air Basin. Figure 1-1 shows the boundaries of the 

District; also shown are the federally designated ozone nonattainment areas. In May 

1996, the boundaries of the South Coast Air Basin were changed by ARB to include the 

Beaumont-Banning area. In addition, the Southeast Desert Air Basin was separated into 

two areas and renamed as the Mojave Desert Air Basin and the Salton Sea Air Basin. 

The South Coast Air Basin is bounded by the Pacific Ocean to the west and the San 

Gabriel, San Bernardino, and San Jacinto Mountains to the north and east. It includes all 

of Orange county and the non-desert portions of Los Angeles, Riverside, and San 

Bernardino counties. The Los Angeles county portion of the Mojave Desert Air Basin 

(known as North county or Antelope Valley) is bounded by the San Gabriel Mountains to 

the south and west, the Los Angeles/Kern county border to the north, and the Los 

Angeles/San Bernardino county border to the east. In September 1996, AB 2666 

(Knight) established the Antelope Valley Air Pollution Control District (AVAPCD) to be 

effective on July 1, 1997. In the interim, the Antelope Valley is considered part of the 

South Coast Air Quality Management District. As such, the planning requirements for 

the Antelope Valley are provided in this Plan. The Riverside county portion of the 

Salton Sea Air Basin and the Mojave Desert Air Basin is bounded by the San Jacinto 

Mountains in the west and spans eastward up to the Palo Verde Valley (Blythe).

While the state action redrew the boundaries of the desert regions of Southern California, 

the federal ozone nonattainment area is still called the Southeast Desert Modified Ozone 

Nonattainment Area and contains portions from all three air basins. The Salton Sea Air 

Basin portion of Riverside County east of the South Coast Air Basin (known as the 

Coachella Valley Planning Area) is bounded by the San Jacinto Mountains to the west 

and the eastern boundary of the Coachella Valley to the east.

The topography and climate of Southern California combine to make the Basin an area of 

high air pollution potential, and constrain the District’s efforts to achieve clean air. 

During the summer months, a warm air mass frequently descends over the cool, moist 

marine layer produced by the interaction between the ocean’s surface and the lowest 

layer of the atmosphere. The warm upper layer forms a cap over the cool marine layer 
Chapter 1 Introduction

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and inhibits the pollutants in the marine layer from dispersing upward. In addition, light 

winds during the summer further limit ventilation. Furthermore, sunlight triggers the 

photochemical reactions which produce ozone, and this region experiences more days of 

sunlight than any other major urban area in the nation except Phoenix.

Southeast Desert Nonattainment Area

Antelope Valley

South Coast Air Quality Management 

District Boundaries

Coachella Valley Planning Area

FIGURE 1-1

Boundaries of the South Coast Air Quality Management District

and Federal Planning Areas

[Note: A New District (Antelope Valley Air Pollution Control District) was Formed in 

September 1996 and Will Be Effective on July 1, 1997.]

The Basin’s economic base is diverse. Historically, the four counties of the Basin have 

collectively comprised one of the fastest-growing local economies in the United States. 

Until recently, the aerospace and electronic industries accounted for about 20 percent of 

the Basin’s employment. Significant changes have occurred in the composition of the 
FINAL 1997 AQMP

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industrial base of the region in the past ten years. As in many areas of the country, a 

large segment of heavy manufacturing, including steel and tire manufacturing and 

automobile assembly, has been phased down. The aerospace and electronics industries 

have been reduced in scale by cutbacks in defense spending. Small service industries 

and businesses resulting from growth in shipping and trade have replaced much of the 

heavy industry.

Both the Antelope Valley and the Coachella Valley Planning Area are impacted by 

pollutant transport from the South Coast Air Basin. In addition, pollutant transport 

occurs to the Mojave Desert, Ventura county, and San Diego county. As part of this 

AQMP revision, transport issues relative to the Antelope Valley and the Coachella 

Planning Area are specifically addressed in Chapter 8 and Appendix V.

In summary, the diverse geographical characteristics of the Southern California region 

place a significant constraint on achieving air quality standards.

Emission Sources

The pollution burden of the Basin is substantial. It has been estimated from prior studies 

that emissions of volatile organic compounds, oxides of nitrogen, carbon monoxide, 

sulfur oxides, and direct primary particulates in the South Coast Air Basin must be 

reduced by over 50 percent to attain the federal air quality standards.

Air pollution forms either directly or indirectly from pollutants emitted from a variety of 

sources. These sources can be natural, such as oil seeps, vegetation, or windblown dust. 

Emissions may also result from combustion, as in automobile engines; from evaporation 

of organic liquids, such as those used in coating and cleaning processes; or through 

abrasion, such as from tires on roadways. The air pollution control strategy in the 

AQMP is directed almost entirely at controlling man-made sources. Where naturally 

occurring emissions can be mitigated, such as through windbreaks, they are included. 

Otherwise, natural emissions are accounted for in the background and initial conditions 

data used for the air quality modeling analysis described in Chapters 5 and 8 and 

Appendix V.

Population

Since the end of World War II, the Basin has experienced faster population growth than 

the rest of the nation. Although growth has slowed somewhat, the region’s population is 

expected to increase significantly towards the end of the century and through 2020. 

Table 1-1 shows the projected growth based on SCAG’s regional growth forecast.
Chapter 1 Introduction

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Although per-capita emissions have been brought down substantially in the Basin 

through 40 years of implementing pollution controls, increases in the population over 

that time have made overall emission reductions more difficult. Many sources, such as 

automobiles, have been significantly controlled. However, increases in the number of 

sources, particularly those growing proportionally to population, reduce the potential air 

quality benefits of new controls. The net result is that unless significant steps are taken 

to further control air pollution, growth will overwhelm much of the improvements 

expected from the existing control program.

TABLE 1-1

Population Growth

Year Population Average Percent Increase 

Per Year Over the Period

1950 4.8 million

1980 10.5 million 2.7

1990 13.0 million 2.2

2010 16.7 million 1.3

2020 18.9 million 1.2

CONTROL EFFORTS

History

The seriousness of the local air pollution problem was recognized in the early 1940s. In 

1946, the Los Angeles County Board of Supervisors established the first air pollution 

control district in the nation to address the problems of industrial air pollution. In the 

mid-1950s, California established the first state agency to control motor vehicle 

emissions. Countywide or regional air pollution districts were required throughout the 

state by 1970. Many of the controls, originating in California, became the basis for the 

federal control program which began in the 1960s.

Nearly all control programs developed to date have relied on the development and 

application of cleaner technology and add-on emission control devices. Industrial and 

vehicular sources have been significantly affected by this technology. Only recently 

have preventive efforts come to the forefront of the air pollution control program, [e.g., 

alternative materials, waste minimization, and maintenance procedures for industrial 

sources].
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In the 1970s, it became apparent at both the state and federal levels that local programs 

were not enough to solve a problem that was regional in nature and did not stay within 

jurisdictional boundaries. Instead, air basins, defined by geographical boundaries, 

became the basis for regulatory programs.

In 1976, the California Legislature adopted the Lewis Air Quality Management Act 

which created the South Coast Air Quality Management District from a voluntary 

association of air pollution control districts in Los Angeles, Orange, Riverside, and San 

Bernardino counties. The new agency was charged with developing uniform plans and 

programs for the region to attain federal standards by the dates specified in federal law. 

The agency was also mandated to meet state standards by the earliest date achievable, 

using reasonably available control measures.

Rule development in the 1970s and 1980s resulted in dramatic improvement in Basin air 

quality (see Appendix II). However, the effort to impose incremental rule changes on the 

thousands of stationary sources under District permits was laborious and time 

consuming. The District concluded it was possible that the limits of the command and 

control regulatory process were being reached. The 1991 AQMP introduced the concept 

of a Marketable Permits Program and outlined the skeleton of an idea that was 

forerunner to what is now known as the Regional Clean Air Incentives Market 

(RECLAIM).

A historical milestone occurred with the adoption of RECLAIM on October 15, 1993. 

RECLAIM is an alternative means of achieving further emission reductions from 

stationary sources, different from the traditional source-specific regulatory program. 

RECLAIM calls for declining mass emission limits on the total emissions from all 

sources within a facility. The facility can choose from a selection of methods for 

achieving the prescribed emission reductions: add-on controls, use of reformulated 

products, changes in production, purchase of excess emission reductions from other 

sources, and/or any other methods that would be enforceable and quantifiable. At the 

time of adoption, RECLAIM was estimated to affect approximately 390 and 41 of the 

largest emitters of oxides of nitrogen and oxides of sulfur in the Basin and is designed to 

reduce emissions of these pollutants by 80 and 14 tons/day, respectively, by July 1, 

2004.1

Impact of Control

Past air quality programs have been effective in improving the Basin’s air quality. 

Ozone levels have been reduced in half over the past 30 years, sulfur dioxide and lead 

 

1

RECLAIM, Volume I: Development Report and Proposed Rules; South Coast Air Quality Management District; 

October 1993.
Chapter 1 Introduction

1 - 7

standards have been met, and other criteria pollutant concentrations have significantly

declined. And for the first time in 1992, the federal annual nitrogen dioxide standard 

was not exceeded in the Basin. However, the Basin still experiences exceedances of 

health-based standards for ozone, carbon monoxide, and particulate matter under ten 

microns (PM10). Air quality summaries and health effects in the Basin are briefly 

discussed in Chapter 2; Appendix II provides an in-depth analysis of air quality as 

measured within the District’s jurisdiction.

1994 AIR QUALITY MANAGEMENT PLAN

In September 1994, the District and SCAG adopted an Air Quality Management Plan for 

the Basin which revised the previous AQMPs. The 1994 AQMP continued an aggressive

emission control program with primary emphasis on mobile sources. The control 

program consists of short- and intermediate-term control measures and long-term (or new 

technology) measures. The long-term control measures would be implemented after 

2000 to achieve the federal ozone air quality standard by 2010. The 1994 AQMP 

proposed a comprehensive set of control measures that included market incentive 

approaches for stationary sources, introduction of market incentive concepts that could 

replace indirect source control measures, and the use of advanced technologies for 

stationary and mobile sources. The need to build the infrastructure for new mobile 

source technologies was also identified.

The 1994 AQMP addressed specific requirements of the 1990 federal Clean Air Act and 

the state Clean Air Act. Specifically, the 1994 AQMP provided an ozone attainment 

demonstration as required in the 1990 federal Clean Air Act and served as the triennial 

report update for the South Coast Air Basin as required under state law. Upon the 

adoption of the 1994 AQMP, the District Governing Board requested that only those 

control measures necessary to the federal ozone air quality standard be forwarded to the 

U.S. EPA as part of the ozone State Implementation Plan (SIP).

State and Federal Approval Actions on the 1994 AQMP

Subsequent to the adoption of the 1994 AQMP, the California Air Resources Board 

(ARB) took actions to approve the 1994 AQMP as part of the California Ozone SIP. In 

November 1994, the ARB approved the California Ozone SIP and replaced many of the 

AQMP mobile source control measures with statewide mobile measures. In addition, 

ARB replaced the AQMP consumer products and pesticide control measures with 

statewide measures. All of the statewide measures provide equivalent emission 

reductions to those replaced AQMP measures. The California Ozone SIP was forwarded 

to the U.S. EPA on November 15, 1994 and a completeness finding was made on April 

18, 1995.
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The U.S. EPA proposed two actions on the California Ozone SIP. The first action on 

August 21, 1995, approved several of the long-term new technology measures in the 

Ozone SIP and several of the statewide mobile source control measures. On March 8, 

1996, the U.S. EPA proposed actions to approve the California Ozone SIP. The 

proposed actions were finalized on September 26,1996 and will be effective 30 days 

after publication in the Federal Register. As part of the final action, U.S. EPA will enter 

into a consultative process to further develop the assignment of emission reductions to 

federal transportation sources (locomotives, ships, and aircrafts) needed to achieve the 

federal ozone air quality standard in the South Coast Air Basin. The consultative process 

is anticipated to be completed by the summer of 1997 and if necessary, a revised ozone 

attainment demonstration would be submitted by the end of 1997.

Progress in Implementing the 1994 AQMP

Progress in implementing the 1994 AQMP can be measured by the number of control 

measures that have been adopted as rules and the resulting tons of pollutants targeted for 

reduction. Since 1994, nine control measures have been adopted by the District through 

September 30, 1996. Table 1-2 lists the District stationary and mobile source control 

measures from the 1994 AQMP that were adopted through September 30, 1996.

The primary focus of the District’s efforts had been the development of the VOC 

RECLAIM program since 1994. The VOC RECLAIM control measure (CTS-01) was 

put on hold by the District Governing Board in October 1995 due to lack of consensus on 

major policy issues. Concurrent actions by the Governing Board placed the substitution 

measures identified in the 1994 AQMP as the primary regulatory program. The District 

is currently developing regulations to implement the substitution measures and these 

measures are discussed in Chapters 4 and 7.

Additional rules have been adopted by the ARB to further reduce emissions from mobile 

sources and consumer products. In addition, the Phase 2 reformulated fuels program 

(known as California Cleaner Burning Gasoline) began in the spring of 1996 and is 

projected to further reduce Basin-wide emissions of volatile organic compounds, oxides 

of nitrogen, carbon monoxide, and oxides of sulfur.1 

 

1 Emission Benefits Analysis - Phase 2 Reformulated Gasoline; Air Resources Board; January 13, 1993.
Chapter 1 Introduction

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TABLE 1-2

District Control Measures Adopted From

September 1994 Through September 1996

Control Measure Rule Pollutant Title

CTS-05 14122 VOC Further Emissions Reductions from 

Perchloroethylene Dry Cleaning 

Operations

FUG-01 462 VOC Emission Reductions from Organic 

Liquid Transfer and Loading

FUG-02 1176 VOC Emission Reductions from 

Wastewater Systems (formerly titled 

“Emission Reductions from Active 

Draining of Liquid Products”

RFL-02 461 VOC Further Control of Emissions from 

Gasoline Dispensing Facilities

CTS-C 1171 VOC Emission Reductions from Solvent 

Cleaning Operations

MOF-03 1623 All Emission Reduction Credits for Leaf 

Blowers

MOF-04 1620 All Off-Road Mobile Source Emission 

Reduction Programs

MON-01 1612 All Emission Reduction Credits for LowEmissions Retrofit Fleet Vehicles

MON-05 1612 All Emission Reduction Credits for 

Heavy-Duty Buses

MON-06 1612 All Emission Reduction Credits for 

Heavy-Duty Trucks

2 Perchloroethylene has been delisted as a VOC by the U.S. EPA since the adoption of Rule 1412 and is no 

longer reported in the VOC emissions inventory, however, it is still considered a toxic air contaminant.

Local governments can play an active role in reducing mobile source emissions through 

the implementation of specific actions. Since 1994, a task force jointly chaired by the 

District and SCAG has been working on possible on-road pricing market incentive 

approaches. The REACH (Reduce Emissions and Congestion on Highways) Task Force 
FINAL 1997 AQMP

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has developed several such approaches for further analysis. The status of the current 

efforts is discussed in Chapter 7 and in Appendix IV.

The Southern California Economic Partnership (The Partnership) was established in late 

1994 and has been developing approaches to initiate the development of various 

infrastructures needed for alternative fuel programs. A discussion of the progress of the 

Partnership is provided in Chapter 7.

Global Warming and Stratospheric Ozone Depletion Policy

On April 6, 1990, the District adopted a “Policy on Global Warming and Stratospheric 

Ozone Depletion.” The Policy commits the District to consider global impacts in 

rulemaking and in drafting revisions to the AQMP. 

In March of 1992, the District’s Governing Board reaffirmed this policy and adopted 

amendments to the policy to include the following directives:

 phase out the use and corresponding emissions of chlorofluorocarbons (CFCs), 

methyl chloroform (1,1,1-trichloroethane or TCA), carbon tetrachloride, and 

halons by December 1995;

 phase out the large quantity use and corresponding emissions of 

hydrochlorofluorocarbons (HCFCs) by the year 2000;

 develop recycling regulations for HCFCs;

 develop an emissions inventory and control strategy for methyl bromide; and

 support for the adoption of a California greenhouse gas emission reduction goal.

In support of these policies, the District Governing Board has adopted several rules to 

reduce ozone depleting compounds. Several other rules concurrently reduce global 

warming gases and criteria pollutants. In the future, these policies will be further 

implemented principally through federal actions.

Toxic Air Contaminant Control Programs

The District is also developing and implementing rules to control Hazardous Air 

Pollutants (HAPs). These control programs have been designed to meet federal and state 

requirements. The District is required to develop such programs under federal and state 

law. 
Chapter 1 Introduction

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At the federal level, Title III of the Clean Air Act provides a program for the control of 

189 HAPs. The first stage of the program involves the promulgating of National 

Emission Standards for HAPs (NESHAPs) to reduce HAP emissions from new and 

existing sources. Major sources will be required to implement Maximum Available 

Control Technology (MACT). Area sources will be required to implement general 

achievable control technology (GACT). This will be followed by a second phase in 

which residual risk will be evaluated and further controls considered. 

The District will implement the NESHAPs MACT (including the standards) through its 

Title V permitting program for major sources or regular permitting for area sources (EPA 

has deferred Title V permitting for area sources for the next five years). The District 

continually evaluates its existing rules to determine whether they need to be amended to 

meet new MACT standards, or whether new rules need to be developed. 

At the state level, the California state legislature has enacted several programs directed at 

toxic air contaminants (TACs). These programs include the Tanner Toxics Act (AB 

1807), Air Toxics Hot Spots Assessment Program (AB 2588), Toxic Emissions Near 

Schools Program (AB 3205), and Disposal Site Air Monitoring Program (AB 3374). 

These programs are currently being implemented by the District either through the 

District rulemaking, permitting, monitoring or AB 2588 program. 

The AB 1807 program, in particular, requires ARB to adopt air toxic control measures 

(ATCMs) to reduce levels of exposure and the risks associated with those levels. At 

present, the District has developed and is implementing eight rules that control emissions 

from specific sources of TACs. These rules meet and in some instances exceed the 

requirements set forth in the ATCM. The District will continue to implement this 

program through new rulemaking as ARB adopts additional ATCMs. Currently, under 

state law, the federal NESHAPs becomes an ATCM, unless ARB has already adopted an 

ATCM for the source category and the hazardous air pollutant(s). 

1997 AQMP REVISION

As mentioned earlier in this chapter, this 1997 Revision to the AQMP is designed to 

satisfy the planning requirements of both the Federal Clean Air Act and the California 

Clean Air Act. The 1994 AQMP is the primary basis for the 1997 AQMP with many of 

the 1994 AQMP control measures carried into the 1997 AQMP. A majority of the 1994 

AQMP control measures are updated in terms of the proposed adoption and 

implementation schedule.
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Federal Clean Air Act Planning Requirements

In November 1990, Congress enacted a series of amendments to the Clean Air Act 

intended to intensify air pollution control efforts across the nation. One of the primary 

goals of the 1990 Clean Air Act Amendments was an overhaul of the planning provisions

for those areas not currently meeting National Ambient Air Quality Standards (NAAQS). 

The CAA identifies specific emission reduction goals, requires both a demonstration of 

reasonable further progress and an attainment demonstration, and incorporates more 

stringent sanctions for failure to attain or to meet interim milestones. The discussion that 

follows briefly presents the general planning requirements of the CAA, lists previous 

State Implementation Plan (SIP) submittals, and introduces CAA provisions that are 

addressed in the 1997 AQMP.

General Requirements

In general, the federal CAA does not necessitate significant changes in attainment 

planning for the Basin in 1997, except requiring an attainment plan for PM10. The CAA 

requires plans to provide for the implementation of all reasonably available control 

measures “as expeditiously as practicable,” including the adoption of reasonably 

available control technology for reducing emissions from existing sources. Emission 

control innovations in the form of market-based approaches are explicitly encouraged by 

the CAA. As mentioned earlier, the District is the first local agency in the country to 

adopt a market-based approach for controlling stationary source emissions of oxides of 

nitrogen and sulfur. The CAA also requires plans to include standards for reasonable 

further progress, which is defined as annual incremental reductions in emissions of 

relevant air pollutants needed to ensure attainment of the National Ambient Air Quality 

Standards (NAAQS) by the applicable date. A similar demonstration of progress was 

instituted in California with the passage of the California Clean Air Act in 1988. This is 

discussed further later in this chapter.

There are several sets of general planning requirements, both for nonattainment areas 

[Section 172(c)] and for implementation plans in general [Section 110(a)(2)]. These 

requirements are listed and very briefly described in Tables 1-3 and 1-4, respectively. 

The general provisions apply to all applicable pollutants unless superseded by pollutantspecific requirements.

Section 110(a)(2)(A) requires reasonable and enforceable control measures in plans. 

EPA has interpreted this requirement to imply that control measures in a plan be in 

regulatory form (i.e., adopted rules) at the time of the plan submittal. However, EPA has 

the authority to conditionally approve a plan revision based on a commitment to adopt 

specific enforceable measures by not later than one year after the date of conditional 

approval of the plan revision [Section 110(k)(4)].
Chapter 1 Introduction

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TABLE 1-3

Nonattainment Plan Provisions [CAA Section 172(c)]

Requirement Description

Reasonably available 

control measures

Implementation of all reasonably available control measures as 

expeditiously as practicable.

Reasonable further 

progress

Provision for reasonable further progress which is defined as 

“such annual incremental reductions in emissions of the relevant 

air pollutant as are required . . . for the purpose of ensuring 

attainment of the applicable national ambient air quality standard 

by the applicable date.”

Inventory Development and periodic revision of a comprehensive, accurate, 

current inventory of actual emissions from all sources.

Allowable emission 

levels

Identification and quantification of allowable emission levels for 

major new or modified stationary sources.

Permits for new and 

modified stationary 

sources

Permit requirements for the construction and operation of new or 

modified major stationary sources.

Other measures Inclusion of all enforceable emission limitations and control 

measures as may be necessary to attain the standard by the 

applicable attainment deadline.

Contingency measures Implementation of contingency measures to be undertaken in the 

event of failure to make reasonable further progress or to attain 

the NAAQS.
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TABLE 1-4

General Requirements for Implementation Plans 

[CAA Sections 110(b)(2), 182(c)(5), 187, and 189]

Requirement Description 

Ambient monitoring An ambient air quality monitoring program.

Enforcement and 

regulation

A program for the enforcement of adopted control measures and 

emission limitations and regulation of the modification and 

construction of any stationary source to assure that the NAAQS 

are achieved.

Interstate transport Adequate provisions to inhibit emissions that will contribute to 

nonattainment or interfere with maintenance of NAAQS or 

interfere with measures required to prevent significant 

deterioration of air quality or to protect visibility in any other 

state.

Adequate resources Assurances that adequate personnel, funding, and authority are 

available to carry out the plan.

Source testing 

Monitoring

Requirements for emission monitoring and reporting by the 

source operators.

Plan revisions Provisions for revising the air quality plan to incorporate changes 

in the standards or in the availability of improved control 

methods.

Other CAA 

requirements

Adequate provisions to meet applicable requirements relating to 

consultation, notification, and prevention of significant 

deterioration and visibility protection contained in other sections 

of the CAA.

Impact assessment Appropriate air quality modeling to predict the effect of new 

source emissions on ambient air quality.

Permit fees Provisions requiring major stationary sources to pay fees to cover 

reasonable costs for reviewing and acting on permit applications 

and for implementing and enforcing the permit conditions.

Local government 

participation

Provisions for consultation and participation by local political 

subdivisions affected by the plan.

Transportation control 

measures

Provisions requiring that serious and above nonattainment areas 

submit an implementation plan that includes transportation 

control measures considering at least the measures listed in 

Section 108(f).
Chapter 1 Introduction

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EPA guidance3states that regulatory programs tend to be less than 100 percent effective 

for many source categories. Rule effectiveness reflects the ability of a regulatory 

program to achieve all the emission reductions that could be achieved by full compliance 

with the applicable regulations at all sources at all times. An effectiveness factor of 80 

percent is required by EPA for all stationary source and non-tailpipe mobile source 

control measures for the future controlled scenarios. EPA, however, does allow 

exceptions to this rule if data exists to adequately demonstrate that the “real world” 

control percentage is higher. It should be noted that stationary point source controls are 

nearly 100 percent effective so an assumption of 80 percent rule effectiveness 

underestimates the expected emission reductions.

The CAA requires that most submitted plans include information on tracking plan 

implementation and milestone compliance. Requirements for these elements are 

described in Section 182(g) and Section 187(d) for ozone and carbon monoxide, 

respectively. Chapter 7 addresses these issues.

EPA also requires a public hearing on many of the required elements in SIP submittals 

before considering them officially submitted. The 1997 AQMP adoption process 

includes a public hearing on all of the required elements prior to submittal.

CAA Planning Requirements Addressed by the 1997 AQMP

Table 1-5 lists the CAA planning requirements addressed by the 1997 AQMP. The main 

submittal is a PM10 attainment demonstration SIP which is due to the U.S. EPA by 

February 8, 1997. The table lists the relevant CAA section and submittal deadline along 

with the AQMP document or chapter where the submittal is discussed. It may be used as 

a reference guide showing where each of the CAA planning requirements is addressed.

Besides the CAA requirements due prior to this plan revision (i.e., attainment 

demonstration plans for ozone, carbon monoxide, and nitrogen dioxide; 1996 Rate-ofProgress and Post-1996 Rate-of-Progress for ozone; and Best Available Control 

Measures (BACM) for PM10), the CAA requires the District to develop a PM10

attainment demonstration, as given in Section 189.

As specified in Section 189(b)(1)(A) of the Act, the PM10 attainment demonstration is 

due no later than four years after reclassification of an area to “serious.” The South 

Coast Air Basin and the Coachella Valley were reclassified from “moderate” to “serious” 

on February 8, 1993. As part of the attainment demonstration, the plan must also contain 

emission reduction milestones to be achieved every three years until the area is 

 

3

Emission Inventory Requirements for Carbon Monoxide State Implementation Plans; U.S. Environmental Protection 

Agency; OAQPS, Research Triangle Park, NC, March 1991.
FINAL 1997 AQMP

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redesignated attainment and the emission reductions must demonstrate reasonable further 

progress as defined under Section 171(l) of the Act. The 1997 AQMP is designed to 

satisfy the requirements of the CAA provisions for PM10.

TABLE 1-5

CAA SIP Revisions and Submittals in the 1997 AQMP

Submittal CAA Section 1997 AQMP 

Reference

PM10 Attainment Demonstration (Basin) 189(b)(1)(A) Chapter 5

Appendix V

PM10 Attainment Demonstration/Maintenance 

Plan (Coachella Valley)

189(b)(1)(A) Chapter 8

Separate Cover

PM10 Reasonable Further Progress Milestones 189(c)(1) Chapter 6

Appendix V

Maintenance Plan for Nitrogen Dioxide 175A(a) and (d) Chapter 5 and 6

Appendix V

Revision to the Ozone Attainment 

Demonstration (Basin)

182(c)(2)(A) Chapter 5

Appendix V

Revision to the Ozone Attainment 

Demonstration, Mojave Desert Air Basin and 

Salton Sea Air Basin (under District jurisdiction)

182(c)(2)(A) Chapter 8

Appendix V

Revision to the Post-1996 Rate-of-Progress 

Demonstration

182(c)(2)(B) Chapter 6

Appendix V

Revision to the Carbon Monoxide Attainment 

Demonstration

187(b)(1) Chapter 5

Appendix V

Growth Factors -- Appendix III

Control Measure Documentation -- Appendix IV
Chapter 1 Introduction

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PM10 monitoring data in the Coachella Valley indicate that (with the exception of one 

measured PM10 exceedance due to a high-wind natural event) the area has attained the 

federal PM10 air quality standard. The U.S. EPA recently released a natural events policy 

which exempts certain high wind events causing PM10 air quality exceedances as being 

counted as a violation. In applying this policy the Coachella Valley is now eligible for 

consideration by U.S. EPA as having attained the federal PM10 air quality standards. The 

Coachella Valley Maintenance Plan is provided under separate cover and discussed in 

Chapter 8 of this document. Certain portions of this 1997 AQMP will provide 

supporting documentation to that maintenance plan.

With new technical information on emissions estimates, the future-year baseline 

emissions projections changed, thereby requiring updates to previous SIP submittals. In 

particular, the emission budgets currently approved for federal conformity purposes must 

be updated and the California Ozone SIP for the South Coast Air Basin must be updated 

to reflect the best available technical information. In addition, the Carbon Monoxide 

Attainment Demonstration Plan must be revised. As such, the 1997 AQMP provides 

revisions to the previous SIP submittals.

The South Coast Air Basin is the only area in nonattainment of the federal nitrogen 

dioxide air quality standard and under the federal Clean Air Act was to attain the federal 

air quality standard by 1995. Monitoring data for the past three years have shown that 

the federal nitrogen dioxide concentrations were below the federal air quality standard. 

Accordingly, the 1997 AQMP will serve as the maintenance plan for nitrogen dioxide. 

As required under Section 175A(a), the plan must provide for maintenance of the air 

quality standard for at least 10 years after the area is redesignated to attainment. In 

addition, the plan must contain contingency measures to assure that any violations will be 

promptly corrected.

Section 181(a)(1) classifies the Basin as an extreme nonattainment area and states that

the Basin must achieve the federal ozone standard by November 15, 2010. As such, an 

attainment demonstration for ozone was provided as part of the 1994 AQMP and the 

ozone portion of the 1994 AQMP is part of the 1994 California Ozone SIP. The ozone 

attainment demonstration followed U.S. EPA and ARB modeling guidelines and as such 

is based on the photochemical grid model called the Urban Airshed Model (UAM). The 

model evaluation and attainment demonstration are fully presented in Technical Report 

V-B and Appendix V-A of the 1994 AQMP, respectively. Based on new technical 

information, the 1994 AQMP ozone attainment demonstration is revised as part of the 

1997 AQMP revision and the attainment demonstration is summarized in Chapters 5 and 

6 and Appendix V.

According to Section 182(c)(2)(B), the District must demonstrate how the Basin will 

achieve actual volatile organic compound emission reductions of at least three percent 
FINAL 1997 AQMP

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per year averaged over each consecutive three-year period beginning from November 15,

1996 and ending November 15, 2010 (i.e., the Basin’s attainment date). The rate-ofprogress milestone years for the Basin are 1999, 2002, 2005, 2008, and 2010. Section 

182(c)(9) requires that the post-1996 rate-of-progress demonstration must contain a set 

of contingency measures, that is, additional control measures which would be 

implemented in the event of a milestone or attainment failure. Appendix V contains the 

detailed calculations of the post-1996 rate-of-progress demonstration. Chapter 6 

provides an estimation of the emission levels at each of the milestone years compared to 

the CAA target levels. Contingency measures are given in Chapter 9.

State Law Requirements

The California Clean Air Act (CCAA) was signed into law on September 30, 1988, 

became effective on January 1, 1989, and was amended in 1992. Also known as the Sher 

Bill (AB 2595), the CCAA established a legal mandate to achieve health-based state air 

quality standards at the earliest practicable date. The Lewis Presley Act provides that the 

plan must also contain deadlines for compliance with all state ambient air quality 

standards and the federally mandated primary ambient air quality standards [Health and 

Safety Code (H&SC) 40462(a)]. In September 1996, AB 3048 (Olberg) amended 

Sections 40716, 40717.5, 40914, 40916, 40918, 40919, 40920, 40920.5, and 44241, and 

repealed Sections 40457, 40717.1, 40925, and 44246 of the Health and Safety Code 

relating to air pollution. The amendments to the Health and Safety Code will become 

effective January 1, 1997. As such, this plan revision reflects the new state planning 

requirements as they pertain to the South Coast Air Quality Management District. 

Through its many requirements, the CCAA serves as the centerpiece of the Basin’s 

attainment planning efforts since it is generally more stringent than the federal Clean Air 

Act.

Based on pollutant levels, the CCAA divides nonattainment areas into categories with 

progressively more stringent requirements (H&SC 40918-40920). The categories are 

outlined in Table 1-6. The state nonattainment designations are on a county basis. The 

entire Basin is an extreme nonattainment area for ozone. Los Angeles County is the only 

county considered as a serious nonattainment area for carbon monoxide. Although PM10

is not explicitly addressed in the CCAA, it is governed by the Lewis Presley Act. The 

plan therefore provides achieving all federal ambient air quality standards by their 

applicable date and state ambient air quality standards as early as possible.
Chapter 1 Introduction

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TABLE 1-6

California Clean Air Act Nonattainment

Area Classifications (H&SC 40921.5)

Concentration Level (ppm)

Category Ozone Carbon Monoxide

Moderate 0.09 to 0.12* 9.0 to 12.7*

Serious 0.13 to 0.15* > 12.7

Severe 0.16 to 0.20* --

Extreme > 0.20 --

* Inclusive range. 

Serious and above nonattainment areas are required to revise their air quality 

management plan to include specified emission reduction strategies, and to meet 

milestones in implementing emission controls and achieving more healthful air quality. 

The key planning requirements are provided in Table 1-7. Some of these requirements 

are discussed in further detail in the next section. Chapter 6 addresses how these 

requirements are met in the Basin. The CCAA also includes some additional 

requirements that can significantly affect control strategy selection. These requirements 

are provided in Table 1-8. All of these mandates have either already been met through 

District regulations or are included/considered in the preparation of the 1997 AQMP.

Plan Effectiveness

The CCAA requires, beginning on December 31, 1994 and every three years thereafter, 

that each district demonstrate the overall effectiveness of its air quality program. For 

those areas that do not attain state air quality standards by 2000, a comprehensive plan 

update is required to be submitted by December 31, 1997. In addition, Section 40925 of 

the Health and Safety Code requires that the plan incorporate new data or projections 

including, but not limited to, the quantity of emission reductions actually achieved in the 

preceding three-year period and the rates of population-related, industry-related, and 

vehicle-related emissions growth actually experienced in the district and projected for the 

future. The 1997 AQMP serves as the comprehensive plan update for the South Coast 

Air Basin.

TABLE 1-7
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California Clean Air Act Planning Requirements

Requirement Description

Indirect and area source 

controls

An indirect and area source control program

[H&SC 40918(a)(4)],

Best available retrofit 

control technology

Best available retrofit control technology (BARCT) for 

existing sources [H&SC 40918(a)(2))],

New source review A program to mitigate all emissions from new and modified 

permitted sources [H&SC 40918(a)(1))],

Pollutant transport Assessment of relative upwind emissions contributions to 

downwind ozone levels [H&SC 39610(b)],

Transportation control 

measures

Transportation control measures as needed to meet plan 

requirements [H&SC 40918(a)(3))], and

Clean fleet vehicle 

programs

Significant use of low-emission vehicles by fleet operators 

[H&SC 40919(a)(4)].
Chapter 1 Introduction

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TABLE 1-8

California Clean Air Act Requirements for Control Strategy Development

Requirement Description

Rate-of-progress Reducing pollutants contributing to nonattainment by five 

percent per year (H&SC 40914) or all feasible control 

measures and an expeditious adoption schedule,

Public education programs Public education programs [H&SC 40918(a)(6)],

Per-capita exposure Reducing per-capita population exposure to severe 

nonattainment pollutants according to a prescribed schedule 

[H&SC 40920(c)],

Any other feasible controls Any of the feasible controls that can be implemented or for 

which implementation can begin, within 10 years of adoption 

date [H&SC 40920.5(c)], and

Control measure ranking Ranking control measures by cost-effectiveness and 

implementation priority (H&SC 40922).

The Act suggests a number of air quality indicators, including actual emission 

reductions, ozone and carbon monoxide design value improvements, population exposure

reductions, and pollutant concentration hours. In Chapter 6, plan effectiveness is 

illustrated by trends in the following indicators:

 volatile organic compound, oxides of nitrogen, and carbon monoxide emissions,

 nitrogen dioxide, carbon monoxide, and ozone air quality (i.e., exceedance 

days), and

 nitrogen dioxide, carbon monoxide, and ozone populational exposure above air 

quality standards.

Emission Reductions

According to the CCAA, districts must design their air quality management plan to 

achieve a reduction in basinwide emissions of five percent or more per year (or 15 

percent or more in a three-year period) for each nonattainment pollutant or its precursors 

(H&SC 40914). However, an air basin may use an alternative emission reduction 
FINAL 1997 AQMP

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strategy which achieves a reduction of less than 5 percent per year if it can be 

demonstrated that either of the following applies:

 The alternative emission reduction strategy is equal to or more effective than the 

5 percent per year control approach in improving air quality; or

 That despite the inclusion of every feasible measure, and an expeditious 

adoption schedule, the air basin is unable to achieve the 5 percent per year 

reduction in emissions.

For emission reduction accounting purposes, the ARB has established a seven-year initial 

reporting period from January 1, 1988, to December 31, 1994 (Section 70701 of the 

California Code of Regulations). The reporting intervals after this initial period occur 

every three years (i.e., 1997, 2000, etc.). Therefore, the 1997 AQMP must seek to 

achieve a 35 percent emissions reduction for the initial reporting period and a 15 percent 

additional reduction for every subsequent interval.

Population Exposure

The CCAA also requires that the 1997 AQMP control measures reduce overall 

population exposure to criteria pollutants. Specifically, exposure to severe 

nonattainment pollutants above standards must be reduced from 1986 through 1988 

levels by at least 25 percent by December 31, 1994; 40 percent by December 31, 1997; 

and 50 percent by December 31, 2000. Reductions are to be calculated based on percapita exposure and the severity of exceedances. This provision is applicable to ozone, 

carbon monoxide, and nitrogen dioxide in the Basin [H&SC 40920(c)]. The definition of 

exposure is the number of persons exposed to a specific pollutant concentration level 

above the state standard times the number of hours. The per-capita exposure is the 

population exposure (units of pphm-persons-hours) divided by the total population.

Control Measure Ranking

The CCAA requires the District Governing Board to determine that the AQMP is a costeffective strategy that will achieve attainment of the state standards by the earliest 

practicable date (H&SC 40913). In addition, the Plan must include an assessment of the 

cost-effectiveness of available and proposed measures and a list of the measures ranked 

from the least cost-effective to the most cost-effective [H&SC 40922(a)].

In addition to the relative cost-effectiveness of the measures, the District must consider 

other factors as well in developing an adoption and implementation schedule [H&SC 

40922(b)]. The other factors noted in the CCAA include technological feasibility, 

emission reduction potential, rate of reduction, public acceptability, and enforceability. 

Efficiency, equity, and legal authority have also been included in the 1997 AQMP for 
Chapter 1 Introduction

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prioritization purposes because of their importance. The results of the prioritization are 

given in Chapter 6.

Pollutant Transport

The South Coast Air Basin both transports to and receives air pollutants from the coastal 

portions of Ventura and Santa Barbara counties in the South Central Coast Air Basin. 

The South Coast Air Basin also receives air pollutants from oil and gas development 

operations on the outer continental shelf. The 1997 AQMP does not specifically address 

the control requirements for these adjacent areas. However, the control measures in this 

Plan meet both the CAA and CCAA transport requirements and will assist downwind 

areas in complying with the federal ozone air quality standard.

The Antelope Valley and the Coachella Valley are both classified as “severe-17” ozone 

nonattainment areas under the CAA. The San Bernardino county portion of the Mojave 

Desert is under the jurisdiction of the Mojave Desert Air Quality Management District 

(MDAQMD) and is also classified as “severe-17.” These areas must comply with the 

federal ozone air quality standard by 2007. The CAA requires separate attainment and 

post-1996 rate-of-progress demonstrations for each severe air basin under the District’s 

jurisdiction. These were provided separately for the Antelope Valley and the CoachellaSan Jacinto Planning Area in the 1994 AQMP Appendices I-A and I-B, respectively. 

Revisions to the attainment demonstration for these areas are provided in Chapter 8 and 

Appendix V.

Areas upwind of the South Coast Air Basin (primarily Ventura county, but also including 

Santa Barbara county and the outer continental shelf) will need to reduce emissions to 

allow those areas to come into compliance with all air quality standards. If the South 

Coast Air Basin is to comply, sources in these upwind areas may need to reduce 

emissions further (i.e., reduce emissions beyond what may be required to achieve the 

standards in these areas).

FORMAT OF THIS DOCUMENT

This document is organized into eight chapters, each addressing a specific topic. Each of 

the remaining chapters are summarized below.

Chapter 2, “Air Quality and Health Effects,” discusses the Basin’s air quality in 

comparison with the federal and state air pollution standards.

Chapter 3, “Base Year and Future Emissions,” summarizes recent updates to the 

emissions inventories, estimates current emissions by source and pollutant, and projects 

future emissions with and without controls.
FINAL 1997 AQMP

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Chapter 4, “AQMP Control Strategy,” presents the attainment strategies.

Chapter 5, “Future Air Quality,” describes the modeling approach used in the AQMP and 

summarizes the Basin’s future air quality projections with and without controls.

Chapter 6, “Clean Air Act Requirements,” discusses specific federal and state 

requirements as they pertain to the 1997 AQMP.

Chapter 7, “Implementation,” presents the implementation schedule of the various 

control measures and delineates each agency’s area of responsibility.

Chapter 8, “Future Air Quality - Desert Nonattainment Areas,” describes the future air 

quality in the Antelope Valley and the Coachella Valley Planning Area.

Chapter 9, “Contingency Measures,” presents contingency measures as required by the 

federal CAA, and measures for further consideration or deletion.

Chapter 10, “Looking Beyond Current Requirements”, examines the basis for and the 

implications of possible new federal standards for ozone and particulate matter; and 

provides a first look at an ozone air quality analysis for the year 2020. This chapter also 

presents a discussion on uncertainties associated with the technical analysis used to 

develop the 1997 AQMP, including air quality modeling.

For convenience, a “Glossary” is provided at the end of the document, presenting 

definitions of commonly used terms found in the 1997 AQMP.