Chapter 1

Introduction

2012 PM2.5 Plan

SJVUAPCD
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

Chapter 1: Introduction 

2012 PM2.5 Plan 

This page intentionally blank.
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-1 Chapter 1: Introduction 

2012 PM2.5 Plan 

Chapter 1: Introduction 

The U.S. Environmental Protection Agency (EPA) periodically reviews and establishes

health-based air quality standards (often referred to as National Ambient Air Quality 

Standards, or NAAQS) for ozone, particulates, and other pollutants. Although the San 

Joaquin Valley’s (Valley) air quality is steadily improving, the Valley experiences unique 

and significant difficulties in achieving these increasingly stringent standards. Over the 

past couple of decades, the San Joaquin Valley Air Pollution Control District (District) 

has implemented several generations of emissions control measures for those 

stationary and area sources under its jurisdiction. Similarly, the California Air 

Resources Board (ARB) has adopted regulations for mobile sources. Together, these 

efforts represent the nation’s toughest air pollution emissions controls and have greatly

contributed to reduced ozone and particulate matter concentrations in the Valley. 

Despite the significant progress under these regulations, greatly aided by the efforts of 

Valley businesses and residents, many air quality challenges remain, including 

attainment of EPA’s most recent standard for particulate matter that is 2.5 microns or 

less in diameter (PM2.5). 

This 2012 PM2.5 Plan establishes the District’s strategy for attaining the 2006 PM2.5

standard as expeditiously as possible, and synthesizes the District’s strategies for 

improving air quality and public health in the Valley. To provide overall strategic 

direction in developing this 2012 PM2.5 Plan, the District Governing Board adopted the 

following Guiding Principles at its February 2012 public hearing:

1. With public health as our number one priority, meet the national ambient air 

quality standards as expeditiously as practicable. 

2. Use sound science as the plan’s foundation. This includes efforts to assess 

public health impacts, predict future air quality, determine the extent of 

emissions reductions needed, and evaluate the availability, effectiveness, and 

feasibility of emission control measures. 

3. Consider the Valley’s unique challenges and develop cost-effective strategies 

that provide adequate operational flexibility and minimize costs to Valley 

businesses. 

4. Consider all opportunities for timely, innovative, and cost-effective emission 

reductions. Consider traditional regulations, but look beyond traditional 

regulations to incorporate monetary incentives, policy initiatives, guidance 

documents, and outreach, including working with cities and counties to 

incorporate 2012 PM2.5 Plan principles into their general plans. 

5. Given that 80% of the Valley’s NOx emissions originate from mobile sources, 

provide a balanced approach to reducing mobile and stationary source 

emissions. 

6. Devise and implement reasonable strategies that involve the public in reducing 

emissions. 
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-2 Chapter 1: Introduction 

2012 PM2.5 Plan 

7. Prioritize strategies that contribute to the District’s Risk-based Strategy by 

achieving the greatest public health benefits. 

8. Prioritize strategies that contribute to attainment of multiple air quality standards. 

9. Recognize that there is no “silver bullet” for attainment. In this plan and 

upcoming attainment plans, every sector—from the public through all levels of 

government, businesses, and industry—must continue to reduce emissions. 

10. Compel state and federal agencies to provide adequate resources and 

regulatory assistance to reduce emissions from sources under their jurisdiction. 

11. Address air pollutant transport issues with air districts neighboring the Valley. 

12. Provide ample opportunity for public participation and feedback in the design 

and implementation of these plans. Utilize the planning process to also inform 

participants of the Valley’s air quality challenges and successes as well as 

actions that can be taken to improve Valley air quality. 

13. Build off of the successes of the District’s Technology Advancement Program by 

identifying further opportunities to continue fostering technology advancement, 

thus paving the way for new emissions control devices to be increasingly used 

in the San Joaquin Valley. 

1.1 THE VALLEY’S UNIQUE CHALLENGES

The Valley’s geography and meteorology exacerbate the formation and retention of high 

levels of air pollution. Surrounding mountains and consistently stagnant weather 

patterns prevent the dispersal of pollutants that accumulate within the Valley. The 

Valley has significant naturally occurring biogenic emissions. The California landscape

also allows for air pollutant transport within the Valley, as well as between the Valley 

and other air basins. These natural factors will continue to impact the Valley’s progress 

toward attainment of air quality standards. 

The Valley is also one of the fastest growing regions in the state (see Appendix B for 

more information). The Population Research Unit of the California Department of 

Finance (DOF) released interim revised population growth projections in May 2012.

1

 

Based on these revised DOF data, from 2010 to 2020, the Valley’s population is 

expected to increase by 18% (Table 1-1). In contrast, the total population for the State 

of California is projected to increase by only 9% over the same time period. Increasing 

population generally means increases in air pollutant emissions as a result of increased 

consumer product use and more automobile and truck travel. Between 2010 and 2020, 

the Valley’s total vehicle miles traveled (VMT) will increase about 21%,

2

consistent with 

 

1 California Department of Finance [DOF]: Interim Population Projects for California and its Counties 2010-2050. 

(May 2012). Retrieved from http://www.dof.ca.gov/research/demographic/reports/projections/interim/view.php

2 California Air Resources Board: 2009 Almanac – Population and Vehicle Trends Tool. Retrieved July 2012 from 

http://www.arb.ca.gov/app/emsinv/trends/ems_trends.php
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-3 Chapter 1: Introduction 

2012 PM2.5 Plan 

the Valley’s population growth. Also, the Valley is home to the state’s major arteries for 

goods and people movement, which adds to the increases in vehicular traffic.

Table 1-1 Estimated Valley Population by County, 2010-2020 3

County Estimated 2010 Projected 2020

Fresno 932,926 1,083,889

Kern* 841,609 1,041,469

Kings 152,996 179,722

Madera 151,136 183,176

Merced 256,345 301,449

San Joaquin 686,651 795,631

Stanislaus 515,229 582,746

Tulare 443,567 536,429

Total 3,980,459 4,704,511

*Kern County is separated into two air districts: San Joaquin Valley and 

Eastern Kern. This data is the Valley-portion of Kern only. 

Although reducing mobile source emissions is critical to the Valley’s attainment of air 

quality standards, the District does not have direct regulatory authority to reduce motor 

vehicle tailpipe emissions, which are regulated by the EPA and ARB. As described in 

Chapter 6 of this plan and in Appendix C, the District must collaborate with interagency 

partners and use innovative approaches to reduce mobile source emissions. 

As Chapter 3 of this plan details, the formation and composition of PM2.5 can be 

complex, with some species impacting health more than others. Long-term trends show 

that PM2.5 concentrations throughout the Valley have declined since monitoring of this 

pollutant first began and are projected to continue on that trend. In addition to declining 

PM2.5 concentrations, most emissions inventories of PM2.5 precursors are also 

projected to decrease despite future population growth.

Figure 1-1 shows the trend in numbers of days that air monitoring sites recorded 24-

hour PM2.5 averages over 35 μg/m3 at the Modesto, Fresno-First, and BakersfieldCalifornia air monitoring sites. An overall downward trend is apparent when comparing 

the early years of 1999 and 2000 to recent years. The current pattern shows generally 

that the northern Valley has the fewest days over the standard, that the southern Valley 

has the most days over the standard, and that the central Valley registers somewhere 

between the two.

 

3

Ibid. footnote 1.
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-4 Chapter 1: Introduction 

2012 PM2.5 Plan 

Figure 1-1 Trends in Exceedances of the 24-hour PM2.5 Standard

Despite the magnitude of the challenges described above, the Valley has a history of 

success in reducing emissions and improving air quality. The Valley must continue to 

reduce air pollutant emissions to improve air quality and to improve public health 

throughout the Valley. 

1.2 PM2.5 AND ASSOCIATED HEALTH IMPACTS

Particulate matter (PM) is a mixture of solid particles and liquid droplets in the air. PM 

can be emitted directly into the atmosphere (primary PM), or can form as secondary 

particulates in the atmosphere through the photochemical reactions of precursors (when 

precursors are energized by sunlight). Thus, PM is made up of a number of 

components, including acids (such as nitrates and sulfates), organic chemicals, metals, 

and soil or dust particles. PM10 is PM that is 10 microns or less in diameter, and the 

PM2.5 subset includes smaller particles that are 2.5 microns or less in diameter (Figure 

1-2).

Any particles 10 microns or less are considered respirable, meaning they can be 

inhaled into the body through the mouth or nose. PM10 can generally pass through the 

nose and throat and enter the lungs. PM2.5 can be inhaled more deeply into the gas 

exchange tissues of the lungs, where it can be absorbed into the bloodstream and 

carried to other parts of the body. 
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-5 Chapter 1: Introduction 

2012 PM2.5 Plan 

Figure 1-2 PM10, PM2.5, Human Hair, and Fine Beach Sand

The potential health impacts of particle pollution are linked to the size of the particles, 

with the smaller particles having larger impacts. Numerous studies link PM2.5 to a 

variety of health problems, including aggravated asthma, increased respiratory 

symptoms (irritation of the airways, coughing, difficulty breathing), decreased lung 

function in children, development of chronic bronchitis, irregular heartbeat, non-fatal 

heart attacks, increased respiratory and cardiovascular hospitalizations, lung cancer, 

and premature death. Children, older adults, and individuals with heart or lung diseases 

are the most likely to be affected by PM2.5. Many studies have quantified and 

documented the health benefits of attaining EPA’s 2006 PM2.5 standard. For example, 

one 2008 study used the Regional Human Exposure Model (REHEX) to evaluate 

potential Valley health benefits.

4

 As part of developing this 2012 PM2.5 Plan, the 

District utilized an EPA-developed model named BenMAP to quantify the health that 

would be achieved by this plan, as discussed in more detail in Chapter 2 and Appendix 

E. 

Air pollutant health impacts carry economic costs as well. For example, a study 

conducted in 2008 estimated that the economic benefits of meeting EPA’s 2006 PM2.5

standard to be approximately $5.6 billion. Similarly, using the BenMAP model, the 

District estimated an economic and social benefit of $5.5 billion resulting from 

implementing this plan and attaining the PM2.5 standard (see Chapter 2 and Appendix 

E). The applied economic values were based on the cost of treating illness and the 

expressed value people place on avoiding illness and premature death. The 2008 study 

recognized that some known effects of pollutant exposure cannot yet be quantified in 

 

4 Hall, J.V., Brajer, V., Lurmann, F.W. (November 2008). The Benefits of Meeting Federal Clean Air Act Standards in 

the South Coast and San Joaquin Valley Air Basins. Institute for Economic and Environmental Studies, California 

State University, Fullerton. Retrieved from 

http://business.fullerton.edu/centers/iees/reports/Benefits_of_Meeting_Clean_Air_Standards_11-13-08.pdf
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-6 Chapter 1: Introduction 

2012 PM2.5 Plan 

economic terms, so the actual economic benefits of attainment are likely higher than the 

study reports. 

In addition to particle size, the chemical composition of PM2.5 is a primary factor in the 

type and severity of health impacts. There are several PM2.5 species, or chemical 

compounds, summarized in Table 1-2.

Table 1-2 PM2.5 Species

Species Description

Organic carbon

Directly emitted, primarily from combustion sources (e.g. residential wood 

combustion). Also, smaller amounts attached to geologic material and road 

dusts. May also be emitted directly by natural sources (biogenic).

Elemental carbon Also called soot or black carbon; incomplete combustion (e.g. diesel engines)

Geologic material Road dust and soil dust that are entrained in the air from activity, such as soil 

disturbance or airflow from traffic

Trace metals

Identified as components from soil emissions or found in other particulates 

having been emitted in connection with combustion from engine wear, brake 

wear, and similar processes. Can also be emitted from fireworks.

Sea salt Sodium chloride in sea spray where sea air is transported into the Valley

Secondary organic 

aerosol

Secondary particulates formed from photochemical reactions of organic carbon 

Ammonium nitrate

Reaction of ammonia and nitric acid, where the nitric acid is formed from 

nitrogen oxide emissions, creating nitric acid in photochemical processes or 

nighttime reactions with ozone

Ammonium sulfate

Reaction of ammonia and sulfuric acid, where the sulfuric acid is formed 

primarily from sulfur oxide emissions in photochemical processes, with smaller 

amounts forming from direct emissions of sulfur.

Combined water A water molecule attached to one of the above molecules

Understanding various PM2.5 species, including how each forms, how much each

contributes to the Valley’s total PM2.5 concentrations, and how each is linked to 

different public health impacts, is of the utmost importance for the development of an 

effective, health-protecting control strategy (see Chapter 2). For example, ammonium 

nitrate is estimated to comprise about 40% of the Valley’s total PM2.5 concentrations, 

but it is generally regarded as having relatively low toxicity as compared to other types 

of PM2.5. In contrast, metals have higher health impacts, but are found in relatively low 

concentrations in the Valley. Bioaerosols, such as mold spores, bacteria, pollen, and 

endotoxins, carry significant health risks for sensitive individuals. Ultrafine particles, or 

those particles 0.1 microns or less in diameter (PM0.1), are small enough to effectively 

deliver harmful chemicals into the lungs, bloodstream, and the brain, but typically 

comprise a small portion of the Valley’s total airborne PM mass. 

In addition to affecting human health, air pollution also affects the health of the natural 

environment. PM2.5 can be transported from sources hundreds of miles away to 

contribute to visibility problems at remote locations, such as the Sierra Nevada and 

associated national parks. As PM settles out of the air, it can make lakes and streams 

acidic, change an ecosystem’s nutrient balance, and affect ecosystem diversity. PM 

can affect vegetation by damaging foliage, disrupting the chemical processes within 
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-7 Chapter 1: Introduction 

2012 PM2.5 Plan 

plants, reducing light adsorption, and disrupting photosynthesis. This can impact green 

spaces as well as crops. PM can also stain and damage stone and other materials. As 

the Valley progresses toward attainment of EPA’s human-health-based PM2.5 

standards, there will also be less harmful impacts to the surrounding natural 

environment.

1.3 NATIONAL AMBIENT AIR QUALITY STANDARDS

1.3.1 EPA’s Standard-Setting Process 

Clean Air Act (CAA) Sections 108 and 109 require EPA to set health-based standards 

for six criteria pollutants, including PM2.5. EPA periodically reviews existing standards 

to consider the most recent health studies. These reviews are to be conducted every 

five years, though in the past, some standard revisions did not meet the 5-year 

deadline. The review process starts as the Clean Air Scientific Advisory Committee 

(CASAC) analyzes available science and then, if supported by research, suggests to 

EPA a range of revised standards that would protect public health from the adverse 

effects of air pollution. The EPA Administrator appoints CASAC members, who are 

non-EPA experts in the fields of science, engineering, or the social sciences. The 

committee is to provide objective, independent advice to EPA on the technical basis for 

the standard. Thousands of peer-reviewed scientific studies are considered as EPA 

formulates its proposed standard, which is made available for scientific peer review and 

public comment. EPA then sets the standard.

In evaluating and setting new standards, federal law prohibits EPA from taking into 

account economic feasibility. However, economic feasibility issues can be considered 

as EPA promulgates the implementation rules that establish the deadlines for meeting 

the standards and in devising individual control measures aimed at attaining the 

standards.

Once a standard is set, EPA designates an area as attainment or nonattainment based 

on the most recent three years of air quality data available. For some pollutants, EPA 

classifies nonattainment areas as marginal, moderate, serious, severe, or extreme. The 

classification sets the attainment deadline and other planning requirements. The 

classification is to be based on certain air quality parameters, though areas can request 

reclassification with adequate documentation. 

EPA also adopts implementation rules to guide states and local air districts as they 

prepare state implementation plans (SIPs) to bring areas into attainment with the 

standard. While EPA cannot consider costs or difficulty in setting the standards, costs 

and difficulty are inescapable for local air districts as they determine the best way to 

bring areas into attainment. That being said, local air districts must meet planning and 

attainment requirements to avoid federal sanctions and to improve public health. 

There are a number of serious penalties and risks associated with any failure to submit 

approvable attainment strategies for meeting federal standards. Upon development of 

an attainment strategy, an area submits the plan to EPA for approval. If EPA finds that 
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-8 Chapter 1: Introduction 

2012 PM2.5 Plan 

an area fails to submit an approvable plan on time or fails to implement plan 

commitments after the plan has been approved, then the following sanctions may be 

applied:

 Two-to-one offset requirement for major sources, leading to a de facto ban on 

new and expanding business

 Loss of federal highway funds, which would cost the Valley an estimated $250 

million per year 

 A federal implementation plan (FIP), which would result in a loss of local control

Once EPA approves a SIP, that plan becomes federally enforceable. The plan can then 

be enforced by the public or EPA through lawsuits. In addition, failure to reach 

attainment by the deadline would result in the assessment of Section 185 penalty fees. 

1.3.2 Federal PM2.5 Standards and Implementation 

EPA established the first PM2.5 standard in 1997 and in 2005 designated the Valley as 

nonattainment for the 1997 standard. The 1997 standard has two limits of attainment: 

an annual average of 15 micrograms per cubic meter (μg/m3) and a 24-hour average of 

65 μg/m3. The District adopted the 2008 PM2.5 Plan in April 2008 to document its 

regulatory commitments, to demonstrate the anticipated effectiveness of its PM2.5 

strategy to bring the Valley into attainment of the 1997 PM2.5 standard no later than 

April 2015 (based on 2012-2014 data), and to meet other federal requirements. EPA 

approved the 2008 PM2.5 Plan in 2011.

EPA revised the 24-hour average PM2.5 standard to 35 μg/m3 in October 2006.

5

 EPA 

designated the Valley as nonattainment of the 2006 PM2.5 standard in 2009, effective 

December 14, 2009.6 The effective date of designation triggered an attainment plan 

due date of December 14, 2012. 

Areas must attain the 2006 standard within five years of the effective date of EPA 

designations, though up to a five year extension is possible. This sets the Valley’s initial 

attainment date at December 14, 2014, with an extension up to December 14, 2019, if 

needed. This 2012 PM2.5 Plan will demonstrate that the Valley will attain the 2006 

standard as expeditiously as practicable, with all feasible measures and strategies 

being considered to accomplish this goal.

Designation under the national PM2.5 standard (unlike the ozone standard) does not 

use a nonattainment area classification system (i.e., moderate, serious, severe, and 

extreme). Therefore, attainment planning requirements are the same for all PM2.5 

 

5 National Ambient Air Quality Standards for Particulate Matter; Final Rule. 71 Fed. Reg. 200, pp. 61144–61233. 

(2006, October 17). (codified at 40 CFR Part 50) Retrieved from http://www.gpo.gov/fdsys/pkg/FR-2006-10-

17/html/06-8477.htm

6

Air Quality Designations for the 2006 24-Hour Fine Particle (PM2.5) National Ambient Air Quality Standards; Final 

Rule. 74 Fed. Reg. 218, pp. 58688–58781. (2009, November 13). (codified at 40 CFR Part 81). Retrieved from 

www.epa.gov/pmdesignations/2006standards/documents/2009-10-08/FR-11-13-2009.pdf
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-9 Chapter 1: Introduction 

2012 PM2.5 Plan 

nonattainment areas. EPA finalized the PM2.5 Implementation Rule7in April 2007 to 

provide rules and guidance on the CAA requirements for attainment plans required 

under the 1997 PM2.5 standard. On March 2, 2012, EPA issued its “Implementation 

Guidance for the 2006 24-Hour Fine Particle (PM2.5) NAAQS.”8 This memo confirmed

the continued appropriateness of the 2007 implementation rule framework for PM2.5 

attainment planning and provided additional guidance where needed. Table 1-3

summarizes PM2.5 attainment planning requirements and where those requirements 

will be met in this plan.

During the compilation and subsequent implementation of this plan for the 2006 PM2.5 

standard, EPA’s standard-setting process continues. On June 14, 2012, EPA published 

a proposed new annual PM2.5 standard of 12 or 13 μg/m3, with the new standard 

projected to be finalized by December 2012. This new standard will require new 

planning and strategy development, beyond what will be implemented with the 2012 

PM2.5 Plan—such is the nature of complying with overlapping federal standards within 

the rigors of local planning and regulatory processes. This overlap of planning 

requirements is shown in Table 1-4. 

Despite the overlap, efforts to reduce PM2.5 and PM2.5 precursors under one PM2.5 

standard will help the Valley to start progressing toward more stringent PM2.5 

standards on the horizon. This is already occurring with the 1997 and 2006 PM2.5 

standards—the emissions reductions strategy being implemented under the plan for the 

1997 PM2.5 standard will continue to achieve additional emissions reductions as fully 

implemented over the next couple of years, and these reductions will contribute to 

improvements in 24-hour average PM2.5 concentrations, bringing the Valley closer to 

the 2006 standard. Building on the 2007 Ozone Plan and 2008 PM2.5 Plan, the District 

is coordinating emissions reductions strategies whenever possible to address multiple 

standards, to maximize efficiency for staff as well as stakeholders, and to maximize 

health benefits. 

 

7 Clean Air Fine Particle Implementation Rule [PM2.5 Implementation Rule]. 72 Fed. Reg. 79, pp. 20586–20667. 

(2007, April 25). Retrieved from http://www.gpo.gov/fdsys/pkg/FR-2007-04-25/pdf/E7-6347.pdf#page=1

8 U.S. Environmental Protection Agency (2012, March 2). Memorandum from the Office of Air Quality Planning and 

Standards: Implementation Guidance for the 2006 24-Hour Fine Particle (PM2.5) National Ambient Air Quality 

Standards (NAAQS). Retrieved from http://www.epa.gov/ttn/naaqs/pm/pdfs/20120302_implement_guidance_24-

hr_pm2.5_naaqs.pdf
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-10 Chapter 1: Introduction 

2012 PM2.5 Plan 

Table 1-3 Federal Requirements for PM2.5 Nonattainment Areas

General 

Requirements

Federal 

CAA

PM2.5 

Implementation 

Rule

Description 2012 PM2.5 

Plan

Attainment 

demonstration 

due date

172(b) 72 FR 20599

PM2.5 SIPs are due to EPA by December 

14, 2012, three years from the designation 

date.

NA

Attainment date 172(b)(2) 72 FR 20601

Nonattainment areas should reach 

attainment as expeditiously as practicable, 

but no later than 5 years from the 

designation date. EPA may extend the 

attainment date up to 10 years from the 

designation date, considering severity of 

nonattainment and availability and 

feasibility of control measures.

Chapter 9

RACT/RACM 172(c)(1) 72 FR 20609-

20633

SIP provisions should provide for the 

implementation of reasonably available 

control measures (RACM), including, at a

minimum, reasonably available control 

technologies (RACT).

Chapter 5 and 

9

RFP 172(c)(2) 72 FR 20633-

20642

SIP provisions must provide for reasonable 

further progress. Chapter 9

Contingency 

provisions 172(c)(1) 72 FR 20642-20645

The SIP must provide for the 

implementation of specific measures that 

would take effect without further action by 

the State and that would be undertaken if 

the area fails to make RFP or attainment 

on time.

Chapter 9

Emissions 

inventory 172(c)(3) 72 FR 20647-20651

The SIP must include a comprehensive, 

accurate, current inventory of actual 

emissions from all sources of the relevant 

pollutants in the area.

Appendix B

NSR 172(c)(4-5) 72 FR

The SIP must identify and quantify the 

emissions of pollutants that will be allowed 

(in accordance with section 173(a)(1)(B)), 

from the construction and operation of 

major new or modified stationary sources 

in the area. The SIP must require permits 

for new or modified stationary sources.

Appendix H

Other measures 172(c)(6) 72 FR 20599

The SIP must include enforceable 

emission limitations, other control 

measures and techniques, and compliance 

schedules to provide for attainment by the 

applicable deadline.

Chapters 5

through 8
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-11 Chapter 1: Introduction 

2012 PM2.5 Plan 

Table 1-4 Federal Air Quality Standards and Valley Status for PM2.5

PM2.5 Standards and Timelines

1997 PM2.5 2006 PM2.5 2012 PM2.5

LEVEL OF THE 

STANDARD

24-hr: 65 μg/m3

annual: 15 μg/m3

24-hr: 35 μg/m3

annual: 15 μg/m3 To be determined

1997 EPA sets standard 

1998–2004

2005 EPA finalizes attainment 

designations

2006 EPA sets standard 

2007 EPA implementation rule

2008 Attainment plan due

(SJV’s 2008 PM2.5 Plan)

2009 EPA finalizes attainment 

designations

2010

2011 EPA approves SJV plan

 2012 Attainment plan due

(SJV’s 2012 PM2.5 

Plan)

Proposes annual

standard of 12 or 

13μg/m3: June 2012

Final standard to be 

issued: December 2012

2014 Initial attainment deadline EPA attainment 

designations: December 

2014. 

Attainment plan likely due 

in early 2018, and 

attainment deadline to be 

determined

2015 Final attainment deadline

2016 & beyond

Final attainment deadline: 

2019

1.3.3 State Standards

California also sets ambient air quality standards for several pollutants, including PM2.5. 

The California ambient air quality standards are considerably more stringent than the 

federal standards and are more protective of human health. California’s annual average 

PM2.5 standard is currently 12 μg/m3. There is no California standard for 24-hour 

average PM2.5 concentrations. 

California has no specific attainment date for state air quality standards, nor does it 

require attainment plans. In fact, California Health and Safety Code (CH&SC) Section 

39602 says, “Notwithstanding any other provision of this division, the state 

implementation plan shall only include those provisions necessary to meet the 

requirements of the [federal] Clean Air Act.” Federal standards thus provide the 

framework for SIPs, such as this PM2.5 plan. However, progress toward federal 

standards also brings areas closer to the lower, California standards. 
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-12 Chapter 1: Introduction 

2012 PM2.5 Plan 

1.4 PUBLIC PROCESS OF PLAN DEVELOPMENT

To ensure that the public has the opportunity for meaningful involvement in reviewing 

and commenting on the plan, the District has been using the following timeline for the 

public process (Table 1-5).

Table 1-5 2012 PM2.5 Plan Development and Public Workshop Timeline

Ongoing

Outreach on plan process and findings: 

presentations/discussions with stakeholders at 

various meetings

April 27th and 30th 2012 Public workshops and commenting period

June 2012 Public workshops and public commenting 

October 9, 2012 Public workshops and public commenting 

November 2012 Proposed draft of the plan

December 20, 2012 District Governing Board hearing to adopt the plan 

January 2013

ARB hearing to adopt the SJV plan and the state 

strategy

The District has held a number of meetings and workshops throughout development of 

this plan to seek public input. These meetings have been well-attended by members of 

the public, and a number of questions have been raised and discussed. The District 

has discussed the 2012 PM2.5 Plan at numerous meetings of District Governing Board, 

Citizens Advisory Committee (CAC), Environmental Justice Advisory Group (EJAG), 

and other meetings (including an April meeting with the Central Valley Air Quality 

Coalition). 

The comments and questions received during workshops and associated written 

comment periods have been integral to development of this plan. All significant 

comments and responses are summarized in Appendix I of this plan. The following 

summarizes the recent public workshops:

April 27, 2012 

2012 PM2.5 Plan Technical Symposium 

The District and ARB staff co-hosted a technical symposium on the scientific basis of air 

quality modeling being conducted for the 2012 PM2.5 Plan. Attendees included District 

staff, ARB staff, EPA staff, and members of the public. The meeting, which was hosted 

in Fresno, could be attended via VTC in the District’s Modesto and Bakersfield offices, 

or attended via webcast. Presenters representing District staff, ARB staff, and UC 

Davis researchers addressed the scientific basis of modeling for the plan, the nature of 

PM2.5 species and formation in the Valley, a review of modeling results from CRPAQS 

(the California Regional Particulate Air Quality Study), modeling for state 
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-13 Chapter 1: Introduction 

2012 PM2.5 Plan 

implementation plan purposes, and the technical approach for 2012 PM2.5 Plan 

modeling. These presentations and the discussions that followed provided a valuable 

opportunity to improve understanding of how PM2.5 is formed and retained in the 

Valley, as well as how these processes are analyzed in the plan. 

April 30, 2012 

2012 PM2.5 Plan Workshop 

The District hosted a public workshop on the general direction and first draft 

components of the 2012 PM2.5 Plan. Attendees included District staff, ARB staff, and 

members of the public. District staff presented an overview of federal planning

requirements, the District’s guiding principles for the plan, draft emissions inventory 

trends, ambient PM2.5 trends, and the District’s approach for analyzing control measure 

opportunities. 

June 27, 2012

2012 PM2.5 Plan Workshop 

The District hosted a public workshop on further development of draft 2012 PM2.5 Plan

components. Attendees included District staff, ARB staff, and members of the public. 

District staff presented an overview of the background for the plan, air quality trends, 

development of the risk-based strategy as it is to be incorporated into the PM2.5 plan, 

preliminary control measure findings, and the role of incentives and technology 

advancement in the Valley’s attainment challenges. ARB staff presented an overview of 

photochemical modeling, emissions inventory improvements, and the Valley’s 

preliminary attainment outlook.

October 9, 2012

Two-session 2012 PM2.5 Plan Workshop

The District and ARB hosted a two-session workshop on the 2012 PM2.5 Plan and its 

technical components. Attendees included District staff, ARB staff, EPA staff, and 

members of the public. ARB hosted the morning session to present and respond to 

questions on plan modeling, modeling results, and other analysis. The District hosted 

the afternoon session to present and respond to questions on the plan control strategy, 

demonstration of federal plan requirements, and the public health benefits that would be 

achieved by the PM2.5 Plan. Public comments were heard during the workshop and 

invited on the draft plan. 
San Joaquin Valley Unified Air Pollution Control District December 20, 2012

1-14 Chapter 1: Introduction 

2012 PM2.5 Plan 

This page intentionally blank.