PM10 IMPLEMENTATION/MAINTENANCE PLAN 

AND REDESIGNATION REQUEST 

FOR SACRAMENTO COUNTY 

OCTOBER 28, 2010 

(WITH ERRATA SHEET INCORPORATED) 

SACRAMENTO METROPOLITAN 

AIR QUALITY MANAGEMENT DISTRICT 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Title Page 

Page i 

PM10 IMPLEMENTATION/MAINTENANCE PLAN 

AND REDESIGNATION REQUEST 

FOR SACRAMENTO COUNTY 

OCTOBER 28, 2010 

(WITH ERRATA SHEET INCORPORATED) 

Prepared by: 

Sacramento Metropolitan Air Quality Management District 

777 12th Street, Third Floor 

Sacramento, CA 95814-1908 

(916) 874-4800 

http://www.airquality.org 

Principal Authors: Bruce Katayama, Associate Air Quality Planner 

 Janice Lam, Statistician 

 Steven Lau, Associate Air Quality Planner 

 Hao Quinn, Associate Air Quality Engineer 

 Karen Taylor, Assistant Air Quality Engineer 

Reviewed by: Charles Anderson, Program Coordinator 

Approved by: Brigette Tollstrup, Division Manager 

 Larry Greene, Executive Director/APCO 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Table of Contents 

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TABLE OF CONTENTS 

1. INTRODUCTION ................................................................................................... 1-1

1.1 Background Information ................................................................................. 1-1

1.2 Health Impacts ............................................................................................... 1-1

1.3 Description of Sacramento County PM10 Nonattainment Area ....................... 1-3

1.4 Purpose of Plan ............................................................................................. 1-4

1.5 Plan Development and Public Review Process ............................................. 1-5

1.6 Overview of Plan Contents ............................................................................. 1-6

1.7 References ..................................................................................................... 1-7

2. FEDERAL CLEAN AIR ACT REQUIREMENTS .................................................... 2-1

2.1 PM10 Standards .............................................................................................. 2-1

2.2 Nonattainment Designation ............................................................................ 2-1

2.3 Attainment Determination .............................................................................. 2-2

2.4 Clean Air Act PM10 Planning Requirements ................................................... 2-2

2.5 State Implementation Plan ............................................................................. 2-3

2.6 Clean Data Policy .......................................................................................... 2-5

2.7 Implementation Plan Submittal Elements ...................................................... 2-6

2.8 Maintenance Plan Requirements ................................................................... 2-7

2.9 Redesignation Requirements ......................................................................... 2-8

2.10 References ..................................................................................................... 2-8

3. PM10 MONITORING NETWORK AND AIR QUALITY DATA ................................ 3-1

3.1 Introduction to PM10 Data ............................................................................... 3-1

3.2 PM10 Monitoring Network ............................................................................... 3-2

3.3 PM10 Data Trends .......................................................................................... 3-6

3.4 PM10 Seasonality Analysis ............................................................................. 3-8

3.5 PM10 Speciation Analysis ............................................................................. 3-10

3.6 PM10 Air Quality Data Conclusions .............................................................. 3-11

3.7 References ................................................................................................... 3-12

4. EMISSIONS INVENTORY .................................................................................... 4-1

4.1 Introduction to Emissions Inventory ............................................................... 4-1

4.2 Emissions Inventory Requirements ................................................................ 4-1

4.3 Precursors to PM10......................................................................................... 4-1

4.4 Emissions Inventory Source Categories ........................................................ 4-2

4.5 Base Year Emissions and Forecasts ............................................................. 4-4

4.6 Analysis of Emissions Inventory Forecasts .................................................... 4-8

4.7 General Conformity and Airport Emissions Inventory .................................. 4-10

4.8 Emission Reduction Credits ......................................................................... 4-11

4.9 Emissions Inventory Documentation ............................................................ 4-13

4.10 Emissions Inventory Conclusions ................................................................ 4-13

4.11 References ................................................................................................... 4-13

5. CONTROL MEASURES ....................................................................................... 5-1

5.1 Introduction to Control Measures ................................................................... 5-1

5.2 Control Measure Requirements ..................................................................... 5-1

5.3 RACM/RACT Evaluation ................................................................................ 5-1
PM10 Implementation/Maintenance Plan and 

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5.4 New Source Review Program ........................................................................ 5-5

5.5 Control Measures Conclusions ...................................................................... 5-5

5.6 References ..................................................................................................... 5-6

6. MAINTENANCE DEMONSTRATION .................................................................... 6-1

6.1 Introduction to Maintenance Demonstration................................................... 6-1

6.2 Maintenance Demonstration Requirements ................................................... 6-1

6.3 Maintenance Demonstration Analysis ............................................................ 6-1

6.4 Results of Maintenance Demonstration ......................................................... 6-5

6.5 Future Monitoring Network ............................................................................. 6-6

6.6 Verification and Tracking the Maintenance Demonstration ............................ 6-7

6.7 References ..................................................................................................... 6-7

7. MAINTENANCE CONTINGENCY PLAN .............................................................. 7-1

7.1 Introduction to Contingency Plan ................................................................... 7-1

7.2 Contingency Plan Requirements .................................................................... 7-1

7.3 Maintenance Contingency Plan ..................................................................... 7-1

7.4 Contingency Plan Conclusions ...................................................................... 7-2

7.5 References ..................................................................................................... 7-3

8. TRANSPORTATION CONFORMITY BUDGETS .................................................. 8-1

8.1 Introduction to Transportation Conformity ...................................................... 8-1

8.2 Transportation Conformity Requirements ...................................................... 8-1

8.3 Latest Planning Assumptions ......................................................................... 8-1

8.4 SACOG’s MTP2035 ....................................................................................... 8-2

8.5 Proposed Motor Vehicle Emission Budgets ................................................... 8-3

8.6 Impact of New Emission Budgets .................................................................. 8-5

8.7 References ..................................................................................................... 8-5

9. REDESIGNATION REQUEST .............................................................................. 9-1

9.1 Introduction to Redesignation and Redesignation Requirements .................. 9-1

9.2 Evaluation of Redesignation .......................................................................... 9-2

9.3 References ..................................................................................................... 9-7

10. SUMMARY AND CONCLUSIONS .................................................................. 10-1

10.1 PM10 Nonattainment Designation ................................................................. 10-1

10.2 PM10 Air Quality Data ................................................................................... 10-1

10.3 Emissions Inventory ..................................................................................... 10-1

10.4 Control Measures ......................................................................................... 10-1

10.5 Maintenance Demonstration ........................................................................ 10-2

10.6 Contingency Plan ......................................................................................... 10-2

10.7 Transportation Conformity Budgets ............................................................. 10-2

10.8 Redesignation Request ................................................................................ 10-3

10.9 Overall Conclusions ..................................................................................... 10-3

APPENDICES 

A. EMISSIONS INVENTORY 

B. CONTROL MEASURES 

C. TRANSPORTATION CONFORMITY BUDGETS 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Introduction 

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1. INTRODUCTION 

1.1 Background Information 

Particulate matter (PM) is the term for the mixture of solid and liquid particles in the 

ambient air that we breathe. Because particles originate from a variety of activities and 

processes, their chemical and physical compositions vary widely. Components of PM 

include nitrates, sulfates, elemental carbon, organic carbon compounds, acid aerosols, 

trace metals, and geologic materials. PM can be directly emitted to the air or can be 

produced by secondary formation in the atmosphere when precursor gaseous 

pollutants, such as nitrogen oxides and sulfur oxides, chemically react with ammonia to 

form fine aerosol particles. 

Sources of PM are mainly due to human (anthropogenic) activities, such as residential 

fuel combustion smoke and soot, entrained road dust, motor vehicle exhaust precursor 

pollutants, and dust emissions from construction and farming activities. PM can also be 

generated from natural sources such as windblown dust and wildfires. 

For air quality monitoring purposes, PM is measured and expressed as the mass of 

particles in micrograms per cubic meter (μg/m3) of air. Ambient PM concentrations can 

build up in the Sacramento region due to its valley geography, stagnant wintertime 

meteorology, and urban emission sources. PM may eventually be removed from the 

atmosphere by gravitational settling or deposition, rainout (attaching to water droplets 

as they fall to the ground), and washout (being absorbed by water molecules in clouds 

and later falling to the ground with rain). 

Ambient air quality standards for particulate matter focus on the smaller particle sizes 

that are responsible for adverse health effects because of their ability to reach the lower 

regions of the respiratory tract. PM10 standards established to protect human health 

refer to the air pollutant that consists of particles ten microns or less in diameter (about 

one seventh the width of a human hair). PM10 standards are also designed to protect 

visibility and prevent vegetation damage. 

1.2 Health Impacts 

In developing the national ambient air quality standards (NAAQS) for PM10 exposure, 

the major emphasis has been placed upon community epidemiological studies, along 

with additional toxicological and controlled human exposure studies. These studies 

show that exposure to elevated levels of particulate matter causes adverse human 

health effects, including reduced lung functions, increased respiratory complications, 

cardiovascular disease, lowering the body's defense against infections, injury to lung 

tissue, nonfatal heart attacks, increased risk of cancer and, in extreme cases, 

premature death. People most sensitive to the effects of PM10 are those with influenza, 

asthma and other chronic lung and heart disease, as well as the elderly, young children, 

and exercising adults. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Introduction 

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PM10 is likely to penetrate deep into the lung tissue and lodge in the alveoli, the small air 

sacs in the lung where the essential oxygen transfer occurs. PM10 is too small for the 

natural filtering process of the human body (small hairs and mucous throughout the 

nasal and lung passage) to remove. Researchers studied health effects from short-term 

and long-term exposure to particulate matter concentrations in the air. 

Short-Term PM10 Exposure Studies 

In developing a short-term (24-hour) health-based standard for PM10, EPA examined 

the acute health effects in reported studies, including mortality (death) and various 

morbidity (illness) indicators such as reduced lung function, the rates of upper and lower 

respiratory illness, and related hospital admissions. Studies cited by EPA showed a 

decrease in lung function following particulate pollution occurrences (Dockery, 1982) 

(Dassen, 1986).

Some children, particularly asthmatics, showed higher effects to PM10 indicating that 

they may be a more vulnerable subgroup in the population. Respiratory illness is 

particularly important in children since many studies have indicated that respiratory 

illness events (mostly viral) during childhood are important determinants for future risk 

of chronic respiratory symptoms in adult life. 

Based on mortality data examined, EPA concluded there is evidence that elevated 

particulate levels may increase the risk of death. A large share of the acute-exposure 

mortality and hospitalization occurrences are within the elderly population. These 

studies indicate the most susceptible population segment for mortality risk from 

particulate exposure consists of elderly individuals with preexisting cardiovascular and 

respiratory diseases, such as caused by smoking. 

Long-Term PM10 Exposure Studies 

In initially developing a more long-term (annual average period) health-based standard 

for PM10, EPA considered chronic health effects for both mortality and morbidity related 

to elevated particulate levels. EPA cited several studies which noted a correlation 

between mortality rates and long-term particulate pollution levels (EPA, 1986). These 

studies raised concerns for possible premature death resulting from particulate 

pollution, and their results were considered part of the determination of the margin of 

safety for the standard. 

However, in 2006, after evaluating more recent long-term PM10 exposure research 

studies, EPA concluded that the long-term health impacts were mainly related to 

exposure to fine-sized particles 2.5 microns or less in diameter (71 FR 61198). The 

annual PM10 standard was no longer warranted with the annual PM2.5 standard in place. 

In addition, EPA mentioned that the 24-hour PM10 standard “that would reduce 24-hour 

exposures would also likely reduce long-term average exposures, thus providing some 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Introduction 

Page 1-3 

margin of safety against the possibility of health effects associated with long-term 

exposures.” 

Economic and Social Costs 

Adverse health effects related to ambient particulate matter exposure result in a number 

of economic costs and social consequences. These include increased medical costs, 

hospital admissions, work loss days, school absences, caregiver burdens, and 

premature deaths. The economic valuation estimates for the health impacts associated 

with particulate matter exposures are in the billions of dollars per year for the 

Sacramento region, mainly due to premature deaths. 

1.3 Description of Sacramento County PM10 Nonattainment Area 

Physical Geography (SMAQMD, 2004) 

Sacramento County encompasses approximately 994 square miles and is located at the 

southern end of the Sacramento Valley, which is in the northern portion of California’s 

Central Valley (see Figure 1.1). It is bounded by the Coast and Diablo ranges on the 

west and the Sierra Nevada on the east. 

The prevailing wind is from the southwest, primarily because of marine breezes through 

the San Francisco Bay Delta, although during winter, the sea breezes diminish and 

winds from the north occur more frequently. Between late spring and early fall, a layer of 

warm air often overlays a layer of cool air from the San Francisco Bay Delta, resulting in 

an inversion. Typical winter inversions are formed when the sun heats the upper layers 

of air, trapping below them air that has been cooled by contact with the colder surface of 

the earth during the night. Calm conditions and poor ventilation allow for increased 

ambient air pollution concentrations (CARB, 1994). 

Sacramento County hosts an array of habitat types, which include annual grasslands 

and croplands, valley-foothill riparian habitat, valley-foothill woodlands, freshwater 

emergent wetlands, and riverine habitat. Surface water resources in Sacramento 

County include the Sacramento, American, Cosumnes, and Mokelumne Rivers, all of 

which flow to the Sacramento-San Joaquin Delta. 

Population and Economy 

The region has experienced tremendous growth in population over the past twenty 

years. From 1990–2009, Sacramento County’s population grew from approximately 

1,041,000 to 1,433,000 (California Department of Finance, 2009). A broad spectrum of 

land uses characterizes the developed lands. The Sacramento County infrastructure 

has a well-established and comprehensive transportation system, which is dominated 

by highways and freeways. Downtown Sacramento has high-rise office buildings and 

high density housing, surrounded by suburban development. 
PM10 Implementation/Maintenance Plan and 

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Introduction 

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The major economic activity in the area is government services and retail trade, along 

with significant agricultural, industrial, and construction industries. The agricultural lands 

in Sacramento County are dominated by crop lands in the valley and rangelands in the 

foothills and produce a wide variety of crops. 

Figure 1.1: Location of Sacramento County 

1.4 Purpose of Plan 

The Sacramento Metropolitan Air Quality Management District (SMAQMD) has 

prepared this plan in compliance with the federal Clean Air Act requirements pertaining 

to PM10 nonattainment areas. In 2002, EPA officially determined that Sacramento 

County had attained the PM10 NAAQS by the attainment deadline (67 FR 7082). The 

purpose of this plan is to fulfill the requirements for EPA to redesignate Sacramento 

County from nonattainment to attainment of the PM10 NAAQS by preparing the following 

plan elements and tasks: 

 Document the extent of the PM10 problem in Sacramento County. 

 Determine the emission inventory sources contributing to the PM10 problem. 

 Identify the appropriate control measures that achieved attainment of the PM10

NAAQS. 

 Demonstrate maintenance of the PM10 NAAQS. 

 Request formal redesignation to attainment of the PM10 NAAQS. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Introduction 

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1.5 Plan Development and Public Review Process 

The SMAQMD is a local government air quality regulatory agency for the jurisdiction of 

Sacramento County. This PM10 plan is developed for the Sacramento County 

nonattainment area by the SMAQMD staff with participation from the Sacramento Area 

Council of Governments (SACOG) and the California Air Resources Board (CARB). 

SACOG is the Metropolitan Planning Organization (MPO) for the Sacramento region, 

representing six counties and over 20 member cities. SACOG develops regional 

transportation and land use development plans and acts as a forum for governmental 

and public input on regional issues. 

Because of recent changes in the regional travel demand model data used in 

transportation plans, SACOG was a key contributor in the preparation of the updated 

motor vehicle emissions inventory and transportation emissions budgets. CARB staff 

also provided information regarding mobile and area-wide emissions inventory category 

estimates, state and federal control measures, and PM10 air quality data analysis. 

Existing public working groups are used to disseminate information and seek input from 

a wide variety of key community stakeholders during the development and review 

process of the draft plan. SACOG’s Regional Planning Partnership is an advisory 

committee with close to 100 representatives from local, regional, state, federal, and 

tribal governments, as well as representatives of business, environmental, and minority 

organizations and associations (SACOG, 2010). This venue, which includes local, 

regional, state, and federal air quality and government agencies, serves as the 

interagency consultation process to provide comments on transportation conformity 

budgets and issues. 

A minimum of 30 days for a public hearing notice and review period is needed to solicit 

comments on the proposed PM10 plan. This outreach includes publishing a public notice 

in the Sacramento Bee newspaper and mailing a notice to several thousand interested 

parties and over 2,000 e-mail addresses. The Board of Directors for the Sacramento 

Metropolitan Air Quality Management District is required to hold a public hearing prior to 

considering approval of the PM10 plan, which is scheduled for October 28, 2010. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Introduction 

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1.6 Overview of Plan Contents 

This document includes the information and analyses to fulfill the federal PM10 air 

quality implementation, maintenance, and redesignation planning requirements for the 

Sacramento County nonattainment area. The following chart contains a brief description 

of each chapter in this plan. 

Chapter 1 Provides an introduction that contains background information on PM10 air 

pollution, health impacts, Sacramento County nonattainment area, purpose and 

development of the plan. 

Chapter 2 Explains the current PM10 nonattainment status and defines federal Clean Air 

Act PM10 requirements for implementation, maintenance and redesignation to 

attainment. 

Chapter 3 Analyzes PM10 air quality data and trends in Sacramento County. 

Chapter 4 Presents the PM10 and precursor pollutants baseline emissions inventory and 

the emission forecasts that are based on existing control strategies and growth 

assumptions. 

Chapter 5 Describes control measure requirements and identifies the appropriate control 

measures that achieved attainment and will provide for maintenance of the 

PM10 NAAQS. 

Chapter 6 Includes the data analysis and provisions for a maintenance demonstration. 

Chapter 7 Discusses the maintenance contingency plan. 

Chapter 8 Assesses the motor vehicle emissions budgets for transportation conformity 

purposes. 

Chapter 9 Evaluates the fulfillment of the redesignation requirements. 

Chapter 10 Summarizes the key points and major conclusions of this report. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Introduction 

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1.7 References 

CARB. California Surface Wind Climatology, Aerometric Data Division, CA: California 

Air Resources Board, Sacramento, CA [1994.] p. 13. 

California Department of Finance, Revised Historical City, County and State Population 

Estimates. CA: California Department of Finance, Sacramento, CA [2009.] 

Dassen, W., et al, Decline in Children’s Pulmonary Function During an Air Pollution 

Episode. Journal of Air Pollution Control Associations, 36:1223-1227, [1986.] 

Dockery, D.W., et al. Change in pulmonary function in children associated with air 

pollution episodes. Journal of Air Pollution Control Associations, 32:937-942, 

1982. 

SACOG. Regional Planning Partnership and list of attendees. Sacramento, CA: 

Sacramento Area Council of Governments, Sacramento, CA. Web: 21 

September 2010 

<http://www.sacog.org/about/> and 

<http://www.sacog.org/calendar/2010/07/28/rpp/> 

SMAQMD. Initial Study for Sacramento Area Regional Federal Ozone State 

Implementation Plan Update. Sacramento, CA: Sacramento Metropolitan Air 

Quality Management District, Sacramento, CA [2004.] p. 7-8. 

USEPA. Second Addendum to Air Quality Criteria for Particulate Matter and Sulfur 

Oxides: Assessment of Newly Available Health Effect Information. EPA-600/8-

86-020F, [1986.] 

USEPA. Designation of Areas for Air Quality Planning Purposes, Federal Register, 

Volume 58, December 21, 1993, p. 67334. 

USEPA. Clean Air Act Attainment Finding; Bullhead City and Payson Nonattainment 

Areas, AZ; Sacramento and San Bernardino Nonattainment Areas, CA; 

Particulate Matter of 10 Microns or Less (PM-10), Federal Register, Volume 67, 

February 15, 2002, p. 7082-7085. 

USEPA, National Ambient Air Quality Standards for Particulate Matter, Federal 

Register, Volume 71, October 17, 2006, p. 61198. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Federal Clean Air Act Requirements 

Page 2-1 

2. FEDERAL CLEAN AIR ACT REQUIREMENTS 

2.1 PM10 Standards 

On July 1, 1987, EPA revised the NAAQS for particulate matter with a new PM10

indicator as the basis for the standards (52 FR 24634). The level of the federal PM10

standards was set at 150 μg/m3

 for a 24-hour average concentration1 and 50 μg/m3 for 

an annual average concentration. The new PM10 standards replaced the previous 

standards for total suspended particulates (TSP less than 30 microns in diameter). The 

change from the TSP standards to PM10 was in response to updated information from 

health officials indicating adverse human health effects from the smaller PM10

penetrating deep into the lower respiratory tract and lung tissue. 

In 1997, EPA retained the existing 24-hour and annual PM10 standards after reviewing 

the PM NAAQS. However, EPA expanded the PM NAAQS by adding new PM2.5

standards based on updated human health research impacts from fine-sized particles 

2.5 microns or less in diameter. PM2.5 standards were set at 65 μg/m3 for a 24-hour 

average concentration and 15 μg/m3

 for an annual average concentration (62 FR 

38652). 

In 2006, EPA reaffirmed the 24-hour PM10 standard after reviewing the air quality 

criteria and PM NAAQS again. EPA concluded that the research “evidence continues to 

support a 24-hour averaging time for a coarse particulate standard, based primarily on 

evidence suggestive of associations between short-term (24-hour) exposure and 

morbidity effects and, to a lesser degree, mortality” (71 FR 61198). However, effective 

December 18, 2006, EPA revoked the annual average PM10 standard based on the 

more recent studies indicating long-term health impacts were mainly related to PM2.5

exposure. EPA also tightened the 24-hour average PM2.5 standard by lowering the 

concentration level from 65 μg/m3 to 35 μg/m3 (71 FR 61202).

2.2 Nonattainment Designation 

Upon enactment of the 1990 Clean Air Act Amendments, Sacramento County was 

designated as unclassifiable for PM10 pursuant to Section 107(d)(4)(B)(iii) of the Clean 

Air Act. However, during 1989 and 1990, two different SMAQMD PM10 monitors (Del 

Paso Manor and Stockton Boulevard sites) exceeded and violated the 24-hour PM10

standard. A violation at a monitoring site occurs if the expected number of 24-hour 

NAAQS exceedance days per calendar year is greater than 1.0 averaged over 3 

consecutive years of representative data (40 CFR 50, Appendix K). Effective January 

20, 1994, EPA took final action to redesignate Sacramento County as a “moderate” 

nonattainment area for the PM10 NAAQS (58 FR 67334). Monitoring sites in 

Sacramento County have not violated the annual PM10 NAAQS. 

 

1

 When comparing a 24-hour average PM10 concentration to the federal standard of 150 μg/m3, the 

concentration value is rounded to the nearest 10 μg/m3

. Therefore, the minimum concentration exceeding 

the 24-hour standard is 155 μg/m3

, which rounds to 160 μg/m3. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Federal Clean Air Act Requirements 

Page 2-2 

Areas designated as nonattainment after the enactment of the 1990 CAAA and 

classified as moderate must attain the PM10 NAAQS “as expeditiously as practicable but 

no later than the end of the sixth calendar year after the area's designation as 

nonattainment” (CAA Section 188(c)(1)). Therefore, Sacramento County’s attainment 

deadline for the PM10 NAAQS was established as December 31, 2000. 

2.3 Attainment Determination 

Effective March 18, 2002, EPA officially determined that Sacramento County had 

attained the PM10 NAAQS by the attainment deadline based on PM10 air quality 

monitoring data recorded during 1998 to 2000 (67 FR 7082). The attainment 

determination was based on the following table which summarizes the one-in-six day 

PM10 data collected at five monitoring sites in Sacramento County and reported to EPA. 

The PM10 concentrations showed no measured exceedances of the 24-hour PM10

NAAQS or violations of the annual standard between 1998 and 2000. Since then, the air 

monitoring network includes six PM10 stations throughout Sacramento County, and 

there have not been any measured violations of the PM10 NAAQS. However, this 

determination of attainment by itself does not redesignate Sacramento County to 

attainment for PM10 and additional planning requirements need to be fulfilled. 

Table 2.1: Summary of PM10 Air Quality Data – Sacramento County 1998-2000 

Monitoring site 

Highest 24 hour 

concentration (μg/m3

) Annual average (μg/m3

) 3-year 

annual 

average 

(μg/m3 1998 1999 2000 1998 1999 2000 )

North Highlands 73 73 82 22 26 23 24 

Del Paso Manor 104 141 58 22 27 21 23 

Sacramento – Health Center 79 88 86 23 25 31 26 

Sacramento – Branch Center Rd 81 86 56 27 33 27 29 

Sacramento – T Street 75 99 64 23 29 25 26 

2.4 Clean Air Act PM10 Planning Requirements 

Various federal Clean Air Act planning requirements apply to PM10 moderate 

nonattainment areas. Key sections of the Clean Air Act that relate to nonattainment 

planning requirements for the preparation of this PM10 plan include: 

 Section 110(a) and Section 172 of the Clean Air Act contain general nonattainment 

planning provisions, regarding the public review, adoption, submittal, and content of 

implementation plans. 

 Section 189 of the Clean Air Act specifies additional plan provisions for particulate 

matter nonattainment areas. 

 Section 175A of the Clean Air Act pertains to the submittal of maintenance plans. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Federal Clean Air Act Requirements 

Page 2-3 

 Section 107(d)(3) includes requirements for redesignating a nonattainment area to 

attainment. 

 General Preamble for the Implementation of Title I of the Clean Air Act Amendments 

of 1990 provides a detailed discussion of EPA’s interpretation of the Title I 

requirements (57 FR 13498). 

2.5 State Implementation Plan 

State and air district commitments for attaining and maintaining the NAAQS are outlined 

in a planning document known as the state implementation plan (SIP). The purpose of a 

SIP is to identify a comprehensive strategy needed to achieve the NAAQS by the 

mandated deadline and requirements. The rules and programs in a SIP are then 

implemented over time to reduce the emissions that go into the air, reducing unhealthful 

concentrations of air pollutants and helping areas reach federal air quality standards. 

The following SIP elements are briefly described: 

 

Emissions Inventory 

The SIP must include, “a comprehensive, accurate, current inventory of actual 

emissions from all sources of the relevant pollutant or pollutants in such area, including 

such periodic revisions as the [EPA] may determine necessary to assure that the 

requirements of this part are met.” [CAA Section 172(c)(3)] 

The SIP needs to “identify and quantify the emissions, if any, of any such pollutant or 

pollutants which will be allowed, in accordance with [Section 173(a)(1)(B) of the Clean 

Air Act], from the construction and operation of major new or modified stationary 

sources in each such area.” The SIP needs to “demonstrate to the satisfaction of the 

[EPA] that the emissions quantified for this purpose will be consistent with the 

achievement of reasonable further progress and will not interfere with attainment of the 

applicable national ambient air quality standard by the applicable attainment date.” 

[CAA Section 172(c)(4)] 

Control Measures 

The SIP must “provide for the implementation of all reasonably available control 

measures as expeditiously as practicable (including such reductions in emissions from 

existing sources...through the adoption, at a minimum, of reasonably available control 

technology)”. [CAA Section 172(c)(1)] 

“Such plan provisions shall include enforceable emission limitations, and such other 

control measures, means or techniques (including economic incentives such as fees, 

marketable permits, and auctions of emission rights), as well as schedules and 

timetables for compliance, as may be necessary or appropriate to provide for 

attainment...by the applicable attainment date”. [CAA Section 172(c)(6)] 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Federal Clean Air Act Requirements 

Page 2-4 

Attainment Demonstration 

The SIP needs to include a demonstration (including air quality modeling) that will 

provide for attainment of the national ambient air quality standards by the applicable 

attainment date, or a demonstration that attainment by such date is impracticable. [CAA 

Section 189(a)(1)(B)] 

Reasonable Further Progress 

The SIP is required to contain quantitative milestones which are to be achieved every 3 

years until the area is redesignated to attainment and which demonstrate reasonable 

further progress (RFP) in emission reductions toward attainment by the applicable date. 

[CAA Section 172(c)(2) and Section 189(c)(1)] 

Contingency Measures 

The SIP needs to include “specific measures to be undertaken if the area fails to make 

reasonable further progress, or to attain the national primary ambient air quality 

standard by the [applicable] attainment date”. Contingency measures are to “take effect 

in any such case without further action by the State or the [EPA].” [CAA Section 

172(c)(9)] 

Permits for New and Modified Major Stationary Sources (New Source Review) 

The SIP needs to include provisions for a permit program to require permits for the 

construction and operation of new or modified major stationary sources anywhere in the 

nonattainment area, in accordance with Section 173, Permit Requirements. [CAA 

Section 172(c)(5) and Section 189(a)(1)(A)] 

In addition, the SIP must include provisions to ensure that the control requirements 

applicable to “major stationary sources of PM10 shall also apply to major stationary 

sources of PM10 precursors, except where the [EPA] determines that such sources do 

not contribute significantly to PM10 levels which exceed the [NAAQS] in the area.” [CAA 

Section 189(e)] 

After EPA redesignates Sacramento County to attainment for the PM10 NAAQS, major 

stationary sources will be subject to the prevention of significant deterioration (PSD) 

requirements under Section 160 et seq. of the Clean Air Act, rather than the new source 

review (NSR) nonattainment area provisions of Section 173 (Calcagni, 1992, p. 6). 

Milestone Progress Reports 

After an RFP milestone date occurs as specified in the implementation plan, a progress 

tracking report must be submitted to EPA that demonstrates all applicable measures in 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Federal Clean Air Act Requirements 

Page 2-5 

the plan have been implemented and the RFP emission reduction target has been met. 

[CAA Section 189(c)(2)] 

2.6 Clean Data Policy 

EPA issued a Clean Data Policy on May 10, 1995, which describes the process by 

which EPA will determine that an area has attained the ozone standard and that certain 

SIP planning requirements will not apply so long as the area remains in attainment 

(Seitz, 1995). The area must continue to operate an appropriate air quality monitoring 

network to verify its attainment status. This policy is a determination that certain SIP 

requirements are written so as to be applicable only if the area is not attaining the 

standard. EPA interprets that this Clean Data Policy is applicable to the SIP provisions 

of the CAA with regard to: 

 Attainment demonstrations, 

 Rate of progress plans or reasonable further progress demonstrations, 

 Contingency measures (related to meeting attainment and RFP), 

 Reasonably available control measures (RACM) analysis, 

 Milestone progress reports, and 

 Sanction clocks that had been started for failure to meet related SIP submittal 

requirements. 

In addition, the Clean Data Policy states, “The issuance of a determination pursuant to 

this policy will have no immediate impact on the way conformity is demonstrated. Areas 

will continue to demonstrate conformity using the build/no-build test and [no-greater]-

than-1990 test...(and attainment/RFP SIP, if one with a budget has been submitted).” 

Since areas that are subject to a clean data determination are not required to submit an 

RFP or attainment demonstration SIP, those areas will not generally have approved 

budgets until a maintenance plan is approved as part of the approval of a redesignation 

request. Areas must still produce a basic emissions inventory, and the applicable tests 

for general conformity still apply. 

EPA’s Clean Data Policy interpretations of the Clean Air Act were initially set forth in its 

General Preamble discussions of the relevant provisions of Title I, Part D. EPA 

incorporated the statutory interpretation set forth in the Clean Data Policy in a final rule, 

40 CFR 51.918, to implement the 8-hour ozone NAAQS (70 FR 71644). On December 

14, 2004, EPA issued a memorandum that applied the Clean Data Policy to fine 

particulate matter NAAQS (Page, 2004). EPA also incorporated the statutory 

interpretation set forth in the Clean Data Policy in a final rule, 40 CFR 51.1004(c), to 

implement the PM2.5 NAAQS (72 FR 20603). 

In addition, EPA has applied the Clean Data Policy to the PM10 NAAQS and stated, 

“Our interpretation that an area that is attaining the standards is relieved of obligations 

to demonstrate RFP and to provide an attainment demonstration and contingency 

measures pursuant to part D of the CAA, pertains whether the standard is PM10, ozone, 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Federal Clean Air Act Requirements 

Page 2-6 

or PM2.5” (71 FR 13024). Furthermore, EPA interprets “that RACM requirements are a 

component of an area’s attainment demonstration. Thus, for the same reason the 

attainment demonstration no longer applies...the requirement for RACM no longer 

applies” (71 FR 6354). 

Therefore, under EPA’s Clean Data Policy, the following implementation plan elements 

are not applicable for an area that has already attained the NAAQS and are not 

included in this PM10 plan: 

 Attainment demonstration, 

 Rate of progress plan or reasonable further progress demonstrations, 

 Contingency measures (related to meeting attainment and RFP), 

 Reasonably available control measures (RACM) analysis. 

The Clean Data Policy is the approach being pursued for Sacramento County’s PM10

planning requirements. Any requirements solely related to designation or classification, 

such as new source review, remain in effect until the area is redesignated to attainment. 

Prevention of significant deterioration requirements will apply to Sacramento County 

after redesignation. 

2.7 Implementation Plan Submittal Elements 

The following implementation plan elements have been fulfilled and are included or 

verified in this PM10 plan: 

1. The area must continue to operate an appropriate PM10 air quality monitoring 

network in order to verify its attainment status. 

Chapter 3 of this PM10 plan includes and documents a description of the current PM10

air quality monitoring network in Sacramento County in accordance with 40 CFR 58 – 

Ambient Air Quality Surveillance. 

2. A comprehensive, accurate, current inventory of actual emissions from all sources of 

the relevant pollutants must be completed for the area. 

Chapter 4 of this PM10 plan includes and documents a comprehensive updated 

inventory of actual emissions from all sources of PM10 and nitrogen oxides (NOX), a 

precursor pollutant of PM10 in Sacramento County. 

3. The control measures for the area, which were responsible for bringing the area into 

attainment, must be approved by EPA as meeting reasonably available control 

measures (RACM) and reasonably available control technology (RACT) 

requirements. 
PM10 Implementation/Maintenance Plan and 

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Federal Clean Air Act Requirements 

Page 2-7 

Chapter 5 of this PM10 plan includes and describes the PM10 and applicable PM10

precursor control measures implemented in Sacramento County, which were 

responsible for bringing the area into attainment. It is anticipated that EPA will approve 

these measures as meeting RACM and RACT requirements. 

4. Provide for a permit program to require permits for the construction and operation of 

new or modified major stationary sources of PM10 and applicable PM10 precursors 

(new source review) anywhere in the nonattainment area. 

Chapter 5 of this PM10 plan includes and describes the new source review permit 

program to require permits for the construction and operation of new or modified major 

stationary sources of PM10 and applicable PM10 precursors. 

2.8 Maintenance Plan Requirements 

Section 175A of the Clean Air Act contains planning requirements pertaining to the 

general framework of a maintenance plan. A maintenance plan is a SIP revision that is 

submitted after a nonattainment area attains the applicable national primary ambient air 

quality standard in order to demonstrate future compliance. An approved maintenance 

plan is one of the requirements for redesignating a nonattainment area to attainment. 

CAA Section 175A requires a maintenance plan to: 

 Provide for maintenance of the NAAQS for at least 10 years after redesignation is 

approved by EPA. 

 Contain such additional measures, if any, as may be necessary to ensure such 

maintenance. 

 Include contingency provisions to ensure prompt correction of any violation of the 

standard after redesignation. 

 Provide a contingency measure to implement all control measures contained in the 

nonattainment SIP. 

CAA requirements also specify that a subsequent maintenance plan is required 8 years 

after redesignation. This second plan must provide for maintenance of the NAAQS for 

10 more years after expiration of the first 10-year maintenance period. 

 

In 1992, EPA issued additional discussion, clarification and guidance on requirements 

for redesignation requests and maintenance plans (Calcagni, 1992). This Calcagni 

memorandum includes the following additional provisions needed in a maintenance 

plan: 

 Attainment emissions inventory to identify the level of emissions in the area sufficient 

to attain the NAAQS. 

 Maintenance demonstration of the NAAQS either by showing that future emissions 

will not exceed the attainment level or by modeling to show future emissions will not 

cause a violation of the standard. 
PM10 Implementation/Maintenance Plan and 

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Federal Clean Air Act Requirements 

Page 2-8 

 Verification of continued attainment through operation of an appropriate air quality 

monitoring network. 

 Tracking the progress of the maintenance demonstration by a periodic review or 

update of the factors and assumptions used in the maintenance demonstration. 

2.9 Redesignation Requirements 

Section 107(d)(3)(E) of the Clean Air Act contains the applicable provisions for 

approving a redesignation request to attainment. EPA must determine that the following 

redesignation requirements have been met for an area: 

1. Attained the applicable NAAQS without any further violations. 

2. Has a fully approved applicable implementation plan under CAA Section 110(k). 

3. Demonstrate that the air quality improvement is due to permanent and enforceable 

emission reductions. 

4. Has a fully approved maintenance plan, including a contingency plan, for the area 

pursuant to CAA Section 175A. 

5. Met all relevant requirements under CAA Section 110 and Part D, including Section 

172(c) nonattainment plan requirements and Section 176(c)(4) SIP conformity 

criteria and procedures. 

For an area for which an attainment determination has been made, the SIP submissions 

discussed and suspended under the Clean Data Policy would not be required for the 

area’s redesignation request to be approved since they would no longer be considered 

applicable requirements under CAA Section 107(d)(3)(E). 

Upon redesignation to attainment for the PM10 NAAQS, new source review permitting 

requirements for major stationary sources would no longer apply and prevention of 

significant deterioration requirements would be in effect as required by SMAQMD Rule 

203 – Prevention of Significant Deterioration. 

2.10 References 

Calcagni, John. Procedures for Processing Requests to Redesignate Areas to 

Attainment, Air Quality Management Division, EPA, September 4, 1992. 

Page, Stephen D. Clean Data Policy for the Fine Particle National Ambient Air Quality 

Standards, OAQPS, EPA, December 14, 2004. 

Seitz, John S. Reasonable Further Progress, Attainment Demonstration, and Related 

Requirements for Ozone Nonattainment Areas Meeting the Ozone National 

Ambient Air Quality Standard, OAQPS, EPA, May 10, 1995. 

U.S. Code of Federal Regulations, Title 40, Appendix K to Part 50, referenced 

November 17, 2009. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Federal Clean Air Act Requirements 

Page 2-9 

USEPA. Revisions to the National Ambient Air Quality Standards for Particulate Matter, 

Federal Register, Volume 52, July 1, 1987, p. 24634. 

USEPA. General Preamble for the Implementation of Title I of the Clean Air Act 

Amendments of 1990. Federal Register, Volume 57, April 16, 1992, p. 13498. 

USEPA. Designation of Areas for Air Quality Planning Purposes, Federal Register, 

Volume 58, December 21, 1993, p. 67334. 

USEPA. National Ambient Air Quality Standards for Particulate Matter, Federal 

Register, Volume 62, July 18, 1997, p. 38652-38760. 

USEPA. Clean Air Act Attainment Finding; Bullhead City and Payson Nonattainment 

Areas, AZ; Sacramento and San Bernardino Nonattainment Areas, CA; 

Particulate Matter of 10 Microns or Less (PM-10), Federal Register, Volume 67, 

February 15, 2002, p. 7082-7085. 

USEPA. Final Rule to Implement the 8-Hour Ozone National Ambient Air Quality 

Standard – Phase 2, Federal Register, Volume 70, November 29, 2005, p. 

71644-71646. 

USEPA. Approval and Promulgation of Implementation Plans; Designation of Areas for 

Air Quality Planning Purposes; State of Arizona; Finding of Attainment for Ajo 

Particulate Matter of 10 Microns or Less (PM10) Nonattainment Area; 

Determination Regarding Applicability of Certain Clean Air Act Requirements, 

Federal Register, Volume 71, February 8, 2006, p. 6352-6356. 

USEPA. Approval and Promulgation of Implementation Plans; Designation of Areas for 

Air Quality Planning Purposes; State of Arizona; Particulate Matter of 10 Microns 

or Less; Finding of Attainment for Yuma Nonattainment Area; Determination 

Regarding Applicability of Certain Clean Air Act Requirements, Federal Register, 

Volume 71, March 14, 2006, p. 13021-13025. 

USEPA. National Ambient Air Quality Standards for Particulate Matter, Federal 

Register, Volume 71, October 17, 2006, p. 61198. 

USEPA. National Ambient Air Quality Standards for Particulate Matter, Federal 

Register, Volume 71, October 17, 2006, p. 61202. 

USEPA. Clean Air Fine Particle Implementation Rule, Federal Register, Volume 72, 

April 25, 2007, p. 20586-20667. 
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PM10 Monitoring Network and Air Quality Data 

Page 3-1 

3. PM10 MONITORING NETWORK AND AIR QUALITY DATA 

3.1 Introduction to PM10 Data 

Particulate matter is the term for solid or liquid particles found in the air. Some particles 

are large or dark enough to be seen with the naked eye and can take the form as soot 

or smoke. Others are so small they can be detected only with an electron microscope. 

Because particles originate from a variety of sources (cars, buses, diesel trucks 

(mobile), fireplaces, woodstoves, power plants (stationary), construction demolition, 

wind blown dust, etc.), their chemical and physical compositions vary widely. Particulate 

matter can be directly emitted or can be formed in the atmosphere when gaseous 

pollutants such as sulfur dioxide (SO2) and nitrogen oxides (NOX) react to form fine 

particles. 

In 1987, EPA replaced the earlier total suspended particulate (TSP) air quality standard 

with a PM10 standard. TSP is an outmoded regulatory measure of the mass 

concentration of particulate matter (PM) in community air. It was defined by the 

(unintended) size-selectivity of the inlet to the filter that collected the particles. Under 

windy conditions the mass tended to be dominated by large wind-blown soil particles of 

relatively low toxicity. 

The PM10 standard focuses on smaller particles that are likely responsible for adverse 

health effects because of their ability to reach the lower regions of the respiratory tract. 

The PM10 standard includes particles with a diameter of 10 micrometers or less (0.0004 

inches or one-sixth the width of a human hair – Figure 3.1). EPA's health-based national 

ambient air quality standards for PM10 were set at 50 μg/m3 (measured as an annual 

mean) and 150 μg/m3 (measured as a daily concentration). However, effective 

December 18, 2006, EPA revoked the annual average PM10 standard based on more 

recent studies indicating long-term health impacts were mainly related to PM2.5

exposure. 

Figure 3.1: Human Hair Diameter 
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PM10 Monitoring Network and Air Quality Data 

Page 3-2 

Table 3.1 below shows the standard set forth by EPA for PM10 

Pollutant Primary Standard Averaging Times Secondary 

Standard 

Particulate Matter (PM10) Revoked Annual (Arith. Mean) 

150 μg/m3 24-hour Same as Primary 

EPA determined that the Sacramento PM10 nonattainment area attained the PM10

NAAQS as of December 31, 2000. The PM10 concentrations reported at the time 

included five different monitoring sites, which showed no measured exceedances of the 

24-hour PM10 NAAQS between 1998 and 2000. There are currently six monitoring sites 

in Sacramento County that collect PM10 data. Although the area has not been officially 

re-designated, it has not violated these standards since the 2000 attainment 

determination. 

3.2 PM10 Monitoring Network 

The District operates a network of PM monitors for use in air quality planning and to 

meet federal requirements. Federal regulations require PM10 monitoring networks to 

meet basic objectives: 

 Monitoring the highest concentration of a pollutant 

 Monitoring representative concentrations in areas of high population density 

 Monitoring the impact of major pollutant sources 

 Monitoring pollutant background concentrations 

“Network Design Criteria for Ambient Air Quality Monitoring,”2

 Title 40 Code of Federal 

Regulations, Appendix D to Part 58 defines minimum monitoring requirements based on 

the population of the Metropolitan Statistical Area (MSA) and the design value for each 

NAAQS. Sacramento County is within the Sacramento-Arden Arcade-Roseville MSA. 

The minimum number of monitors for each pollutant is based on the MSA population as 

described in 40 CFR 58 Appendix D. Currently, the Sacramento-Arden ArcadeRoseville MSA has a population of 2.1 million. The monitoring network within the MSA 

exceeds the minimum monitoring requirements for all criteria pollutants. Section 3.0 of 

the 2010 Annual Air Monitoring Network Plan for Sacramento County submitted to EPA 

July 19, 2010 discusses the minimum required monitors for PM10 which is two to four 

monitors. 

There are two types of PM10 monitors used throughout the monitoring network: 1) the 

Federal Reference Method (FRM) filter-based high-volume size-selective inlet sampler 

(hi-vols or SSI), and 2) the Federal Equivalent Method (FEM) tapered element 

oscillating microbalance (TEOM), which measures PM10 on a continuous basis. The 

 

2 “Network Design Criteria for Ambient Air Quality Monitoring,” Federal Register 40 Appendix D to Part 58 
PM10 Implementation/Maintenance Plan and 

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PM10 Monitoring Network and Air Quality Data 

Page 3-3 

schedule for PM10 sample collection is one in six days for the FRM filter-based highvolume samplers, while the FEM TEOM monitors operate on a daily 24-hour schedule. 

There are currently six PM10 monitoring sites within Sacramento County. The District 

operates five of the monitoring sites (Goldenland Court, North Highlands, Del Paso 

Manor Site, Branch Center Rd #2, and Stockton Blvd). The California Air Resources 

Board operates the T Street monitoring site. FRM filter-based high-volume samplers are 

located at all of the six sites listed above for PM10. Del Paso Manor and the Stockton 

Blvd operate both the FRM filter-based samplers and FEM TEOM monitors. Table 3.2 

provides a summary of the monitoring sites in Sacramento County, and Figure 3.2 

shows a map of the locations of Sacramento County monitoring stations. 

The District plans for modifications to the operation of its air quality monitoring network 

for PM10 are presented in the 2010 Annual Air Monitoring Network Plan. The District is 

evaluating relocating the PM10 TEOM monitor at the Del Paso Manor site to the 

Goldenland Court site. The District is also considering the possibility of shutting down 

the PM10 SSI and PM10 TEOM monitors at the Stockton Blvd site. This site’s PM10 SSI 

monitor is not required, and TEOM data is not usable for forecasting or analysis due to 

potential inaccuracies during the winter time when there is wood combustion. The 

SMAQMD older model TEOM monitors contain a heater for reducing moisture, which 

can remove volatile compounds from ambient air samples (such as those in wood 

smoke). In addition, the District is evaluating the possibility of shutting down the PM10

SSI monitors at the Goldenland Court and the North Highlands sites as they are not 

required. The maintenance plan commits to continue to maintain and operate a PM10

ambient monitoring network in Sacramento County that meets or exceeds the minimum 

monitoring requirements. 

 
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PM10 Monitoring Network and Air Quality Data 

Page 3-4 

 Table 3.2: Summary of Monitoring Sites in Sacramento County 

List of Monitoring Sites Within Sacramento County 

Site Name Purpose AQS ID Pollutants/Parameters Monitored3

Branch Center Rd #2 

3847 Branch Center 

Road 

SLAMS 06-067-0284 PM10-SSI 

Elk Grove - Bruceville 

Road 

12490 Bruceville Road SLAMS/ PAMS 06-067-0011 

O3,NO2,Total NMHC, Speciated VOC, BAM 

PM2.5, Ambient Temp., Wind Direction, Wind 

Speed, Relative Humidity, Barometric Pressure, 

Precipitation, Ultraviolet Radiation, Solar 

Radiation, Upper Level Meteorology (Wind Dir., 

Wind Speed, Virtual Temp.) 

Del Paso Manor 

2701 Avalon Drive 

SLAMS/ 

PAMS/ STN/ 

SPM 

06-067-0006 

O3,CO,NO2, SO2,Total NMHC, Speciated VOC, 

Carbonyl, BAM PM2.5, TEOM PM10, PM2.5-FRM 

(main & collocated), PM10-SSI (main & 

collocated), Speciated PM2.5 (SASS), Black 

Carbon, Scattering Coeff., Ambient Temp., Wind 

Direction, Wind Speed, Relative Humidity, Solar 

Radiation 

El Camino – Watt 

3535 El Camino SLAMS 06-067-0007 CO 

Folsom-50 Natoma 

50 Natoma Street SLAMS/ PAMS 06-067-0012 

O3,NO2,Total NMHC, Speciated VOC, BAM 

PM2.5, Ambient Temp., Wind Direction, Wind 

Speed, Relative Humidity, Solar Radiation 

Goldenland Court SLAMS/PAMS 06-067-0014 

O3, CO, NO2, Total NMHC, PM10-SSI, Ambient 

Temp, Wind Direction, Wind Speed, Relative 

Humility, Solar Radiation 

North Highlands 

7823 Blackfoot Way SLAMS/ SPM 06-067-0002 O3,CO,NO2,SO2,PM10-SSI 

Stockton Blvd 

2221 Stockton Blvd SLAMS 06-067-4001 PM2.5-FRM, TEOM PM10, PM10-SSI 

Sloughhouse Road 

7250 Sloughhouse Road SPM 06-067-5003 O3, Wind Direction, Wind Speed, PM2.5 (E-BAM, 

winter PM2.5 SPM study) 

T Street 

1309 T Street SLAMS 06-067-0010 

O3, NO2, PM10-SSI, BAM PM2.5, PM2.5-FRM, 

Speciated PM2.5 (SASS), Ambient Temp., Wind 

Direction, Wind Speed, Relative Humidity, 

Barometric Pressure 

Walnut Grove Tower 

Upper Air 

Research (nonSLAMS site) 

N/A, nonSLAMS site 

Upper level ozone, Wind Direction, Wind Speed, 

Ambient Temp 

Rancho Seco SPM (nonSLAMS site) 

N/A, nonSLAMS site PM2.5 (E-BAM, winter PM2.5 SPM study) 

 

3

 Definition of SLAMS – State and Local Monitoring Stations; NAMS – National Air Monitoring Station; 

PAMS – Photochemical Assessment Monitoring Stations; STN – Speciation Trends Network, SPM – 

Suspended Particulate Matter; FRM – Federal Reference Method; BAM – Beta Attenuation Method; 

NMHC – Non-Methane Hydrocarbon; SSI – Size Selective Inlet; VOC – Volatile Organic Compound 
PM10 Implementation/Maintenance Plan and 

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PM10 Monitoring Network and Air Quality Data 

Page 3-5 

Figure 3.2: Sacramento County Monitoring Stations 
PM10 Implementation/Maintenance Plan and 

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PM10 Monitoring Network and Air Quality Data 

Page 3-6 

3.3 PM10 Data Trends 

Sacramento County was designated as nonattainment for PM10 effective on January 20, 

1994 (58 FR 67334). The PM10 monitoring data showed that Sacramento County 

violated the 150 μg/m3

 federal standard three days between the years of 1989 to 1991. 

Table 3.3 lists the 24-hour PM10 exceedances. 

Table 3.3: Sacramento County Exceedances Violating 24-Hour PM10 Standard 

Monitoring Site Date 24-Hour PM10 Conc. 

Stockton Blvd. November 18, 1989 155 μg/m3

Stockton Blvd. December 18, 1989 158 μg/m3

Del Paso Manor December 25, 1990 187 μg/m3

Table 3.4 shows the historical maximum 24-hour average PM10 concentrations for the 

monitoring sites in Sacramento County for the years 1989-2009 collected by PM10 SSI 

monitors. The highest 24-hour average value of 187 μg/m3

 was from the nonattainment 

designation period in 1990. The lowest peak 24-hour PM10 value of 58 μg/m3 was 

monitored in 2004. The annual peak monitoring site changes from year to year 

throughout the 21-year period, which suggests the potential for elevated PM10

concentrations is mainly caused by emissions from area-wide and mobile source 

activities in the Sacramento area. The peak 1999 24-hour PM10 concentration of 141 

μg/m3 occurred on July 5th at the Del Paso Manor monitoring site, and was likely 

impacted by emissions from Fourth of July fireworks. 

Table 3.4: PM10 Historical Maximum 24-Hour Average Concentrations (μg/m3) for 

Sacramento County Monitoring Sites, 1989-2009 

Year Branch 

Center Rd 

Citrus 

HeightsSunrise 

Blvd* 

Del Paso 

Manor 

Earhart Dr / 

Airport Rd / 

Goldenland 

Ct** 

North 

Highlands

Stockton 

Blvd T Street Peak Site

1989 120 139 147 125 158 140 158 

1990 113 153 187 96 95 140 187 

1991 95 98 127 76 96 98 134 134 

1992 71 89 84 62 79 85 72 89 

1993 80 61 118 104 63 75 77 118 

1994 83 98 76 92 94 99 99 

1995 81 65 90 69 67 85 90 

1996 68 83 59 65 86 75 86 

1997 85 70 36 52 107 108 108 

1998 81 104 93 73 79 75 104 

1999 86 141 70 73 88 99 141 

2000 56 59 73 82 86 64 86 

2001 78 68 51 64 58 89 89 

2002 77 86 73 53 85 77 86 

2003 75 54 57 62 53 65 75 

2004 45 49 47 44 44 58 58 
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PM10 Monitoring Network and Air Quality Data 

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2005 61 72 56 110 64 53 110 

2006 81 63 81 65 56 109 109 

2007 56 70 94 56 56 53 94 

2008 89 71 71 97 88 73 97 

2009 76 45 48 33 45 47 76 

 *Citrus Heights-Sunrise Blvd site closed in 1993. 

**Earhart Dr site closed 1997 and relocated to Airport Rd site 1998. Airport Rd site closed June 2008 and relocated to 

Goldenland Ct site. 

Data source: California Air Resources Board ADAM air quality data base of PM10 FRM SSI monitors. Pre-1994 data 

supplemented by SMAQMD data. 

The chart in Figure 3.3 plots the annual peak 24-hour average PM10 concentration for 

the years 1989-2009 monitored in Sacramento County. This data shows no further 

violations of the 24-hour average PM10 standard since the nonattainment designation 

period. The historical trend (broken) line indicates a decline in the maximum 24-hour 

average PM10 concentrations at the peak monitoring site over the 21-year period. The 

trend line R2 statistic (coefficient of determination = 0.34) is low, which represents a 

weak correlation due to the variability in the data caused by year-to-year differences in 

meteorological conditions and air pollutant emissions patterns. 

Figure 3.3: Peak 24-Hour Average PM10 Concentrations 

Sacramento County 1989-2009 

R2 = 0.345

0

20

40

60

80

100

120

140

160

180

200

1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

YEAR

Maximum 24-Hour PM10 concentration (g/m3

)

Sacramento Peak Monitoring Site 24-Hour PM10 NAAQS Standard Linear (Sacramento Peak Monitoring Site)

Note: The 1999 peak concentration of 141 μg/m3 occurred on July 5th at the Del Paso Manor monitoring site, and was 

likely impacted by emissions from Fourth of July fireworks. 
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PM10 Monitoring Network and Air Quality Data 

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PM10 TEOM Data 

As previously mentioned in this chapter, PM10 data from tapered element oscillating 

microbalance (TEOM) monitors is not used for analysis due to its potential inaccuracies 

during the winter time when there is wood combustion. In Sacramento County, daily 

TEOM monitors have recorded three separate days exceeding, the 24-hour average 

PM10 NAAQS since they were first operated in winter 1992. 

Three TEOM sampler sites exceeded PM10 concentrations over 200 μg/m3 on October 

4, 1995. The Earhart Drive site’s TEOM monitor measured a concentration of 156 μg/m3

on October 21, 1995. The Stockton Blvd-Health Department site’s TEOM monitor 

recorded a concentration of 160 μg/m3

 on September 22, 2006. All of these TEOM 

exceedances of the 24-hour average PM10 NAAQS were flagged and suspected of 

being caused by high wind events. 

A violation at a monitoring site occurs if the expected number of 24-hour NAAQS 

exceedance days per calendar year is greater than 1.0 averaged over 3 consecutive 

years of representative data (40 CFR 50, Appendix K). The TEOM exceedance days 

are based on daily monitoring data sampling. The most exceedance days at TEOM 

sites in any 3-year period would include 1995, and it would be two. Therefore, the 

expected average number of exceedance days per calendar year was less than 1.0, 

and there was no violation of the 24-hour PM10 NAAQS. 

3.4 PM10 Seasonality Analysis 

A PM10 seasonality analysis was conducted to evaluate whether the potential for high 

PM10 was an all year round problem or a more seasonal occurrence in Sacramento 

County. Various meteorological factors4 can vary during the year and play an important 

role in their effect on PM10 levels. 

Wind. Wind speed and direction are important, because they are indicative of the level 

of pollutant dispersion. Predominant winds are from south-southwest during the spring, 

summer and fall. During the winter, predominant winds are coming from north-west and 

south-east. Wind speeds average around 8 miles per hour (mph) during the spring, 

summer, and early fall. Typically, during the late fall and winter, air flows experience a 

significant decrease in speed leading to calm conditions. The light winds and calm 

conditions result in higher air pollution potential, because pollutants can accumulate in 

the area for several days before being dispersed. Wind velocities average 

approximately 5.9 mph for the month of November and 6.4 mph for the month of 

December. 

 

4 Average wind speed, precipitation, and temperature data for Sacramento from: 

National Oceanic and Atmospheric Administration (NOAA) National Data Center website at 

http://ols.nndc.noaa.gov/plolstore/plsql/olstore.prodspecific?prodnum=C00095-PUB-A0001#OVERVIEW 
PM10 Implementation/Maintenance Plan and 

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PM10 Monitoring Network and Air Quality Data 

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Precipitation. Sacramento averages approximately 18 inches of precipitation per year, 

with 90 percent of the annual precipitation falling between November and April. 

November through March averages greater than 2 inches of precipitation per month, 

while the summer months of June through September average less than 1/5 of an inch 

of precipitation per month. As expected, fugitive dust levels are greater in hot, dry 

months when little atmospheric moisture is present to control fugitive dust, although 

studies have also suggested that secondary particulate (nitrates and sulfates) formation 

is enhanced with elevated humidity levels. While elevated PM10 levels have occasionally 

occurred when no measurable precipitation was present, elevated levels have occurred 

with increased humidity. 

Atmospheric Stability and Dispersion. Vertical air movement is important in the 

dispersion of air pollutants. A temperature inversion acts as a nearly impenetrable lid to 

the vertical mixing of the atmosphere and inhibits the dilution of pollution near the 

ground. Inversions occur with great frequency throughout the year in the Sacramento 

Valley, and when they are accompanied by low wind speeds in the winter, pollution 

concentration levels can escalate. 

Temperature. Sacramento temperatures can reach a high of 115 degrees Fahrenheit 

during the summer, and can experience low readings of 18-20 degrees during winter 

months. Low temperatures in the presence of increased humidity are conducive to the 

formation of secondary particulates. In addition, as winter temperatures drop, more 

residents are likely to utilize wood combustion devices such as fireplaces and 

woodstoves for residential heating, increasing PM10 levels. Although in November 2007, 

the District began to implement a program (Rule 421) for mandatory episodic wood 

combustion curtailment on poor air quality days. Rule 421 has been shown to lower 

particulate matter during those poor air quality days.5

PM10 Air Quality Data. Figure 3.4 illustrates the monthly variation in average and peak 

PM10 concentrations monitored in Sacramento County for 1998-2008. Elevated 

concentrations generally occur in fall and winter timeframes, with lowest concentrations 

during spring. The peaks shown in months of May and September may occur due to 

occasions of high winds combined with agricultural burning and agricultural tilling 

activities. Peaks during winter months typically occur from increased secondary 

formation of particulates and more residential wood combustion. This seasonality 

analysis of PM10 FRM SSI data excluded the July 5, 1999 peak concentration of 141 

μg/m3

 at the Del Paso Manor monitoring site since it was likely impacted by emissions 

from Fourth of July fireworks. 

 

5

 “Report on Rule 421 – Mandatory Episodic Curtailment of Wood and Other Solid Fuel Burning 

Effectiveness,” SMAQMD staff report package for May 28, 2009 Board of Directors meeting. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

PM10 Monitoring Network and Air Quality Data 

Page 3-10 

Figure 3.4: Monthly Average and Peak PM10 Concentration Values* for 

Sacramento County, 1998-2008 

0

20

40

60

80

100

120

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Month

Concentration (ug/m3)

Average PM10 1998-2008 2nd High 1st High

*PM10 FRM SSI 24-hour filter average concentration (μg/m3) 

Note: This seasonality analysis excluded the July 5, 1999 peak concentration of 141 μg/m3

 at the Del 

Paso Manor monitoring site since it was likely impacted by emissions from Fourth of July fireworks. 

3.5 PM10 Speciation Analysis 

In 1999, the California Air Resources Board submitted a technical paper on wintertime 

PM2.5 and PM10 source apportionment for Sacramento, California (Motallebi, 1999). The 

Chemical Mass Balance (CMB) modeling calculated source contributions for ambient air 

quality samples (>40 μg/m3

) collected from November to January for 1991-1996. 

Results show that the main source types that contribute to the wintertime PM10 air 

quality problem in Sacramento were (1) secondary particles of ammonium nitrate [29%]; 

(2) motor vehicle exhaust (from cars, trucks, and buses fueled with diesel, leaded 

gasoline, and unleaded gasoline) [23%]; (3) wood smoke (from wood stoves, fire 

places, and agricultural burning) [17%]; and (4) fugitive dust (from tilling and roads) 

[12%]. 

Other sources that have contributed to a lesser extent were secondary particles of 

ammonium sulfate [4%] and traces of residual and crude oil combustion and marinegenerated aerosols (suggesting coastal transport). Approximately 15% of the measured 

PM10 was not explained by the selected source types at the 13th and T Streets site. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

PM10 Monitoring Network and Air Quality Data 

Page 3-11 

Figure 3.5 is a pie chart of the average source contributions to wintertime PM10 1991-

1996 in Sacramento based on Chemical Mass Balance modeling for 24-hour PM10

samples greater than 40 μg/m3. 

Figure 3.5 

Average CMB Source Estimates to 24-Hour PM10 

Sacramento 13th and T Street, Winter 1991-1996 

Secondary 

Ammonium Nitrate, 

28.9%

Motor Vehicles, 

22.9%

Woodsmoke, 16.7%

Unexplained, 14.6%

Fugitive Dust, 12.5%

Secondary 

Ammonium Sulfate, 

4.4%

Average PM10 mass = 51.5 μg/m3

3.6 PM10 Air Quality Data Conclusions 

PM10 air quality data includes solid and liquid particles with a diameter of 10 

micrometers or less. EPA's health-based national ambient air quality standard for 24-

hour PM10 is 150 μg/m3

 (measured as a daily concentration). There are currently six 

PM10 monitoring sites within Sacramento County. 

EPA determined that the Sacramento PM10 nonattainment area attained the PM10

NAAQS as of December 31, 2000 since no exceedances of the 24-hour PM10 NAAQS 

were measured between 1998 and 2000. The air quality monitoring data shows an 

overall declining trend in peak 24-hour PM10 concentrations from 1989 to 2009. Data 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

PM10 Monitoring Network and Air Quality Data 

Page 3-12 

collected since the 2000 attainment determination continues to show that Sacramento 

County meets the federal PM10 standard. 

A PM10 seasonality analysis was conducted to evaluate whether the potential for high 

PM10 was an all year round problem or a more seasonal occurrence in Sacramento 

County. Elevated concentrations during 1998-2008 generally occur in fall and winter 

timeframes, with lowest concentrations during spring. 

The Chemical Mass Balance (CMB) model was used to identify the source contributions 

for ambient air quality samples collected during November to January for 1991-1996. 

CMB results show that the main source types contributing to wintertime PM10 air quality 

in Sacramento were secondary ammonium nitrate particles, motor vehicles exhaust, 

wood smoke, and fugitive dust. 

Historically in Sacramento County, violations of the 24-hour PM10 NAAQS have only 

occurred during late November and December. These peak concentrations typically 

occur due to wintertime weather conditions (e.g., atmospheric stability, low wind 

dispersion, and colder temperatures) conducive to PM10 pollutant build up in conjunction 

with increased secondary formation of particulates and more residential wood 

combustion activities. 

3.7 References 

Motallebi, Nehzat. Wintertime PM2.5 and PM10 Source Apportionment at Sacramento 

California. Air and Waste Management Association 1999: 25-34. 

U.S. Code of Federal Regulations, Title 40, Appendix K to Part 50, referenced 

November 17, 2009. 

USEPA. Designation of Areas for Air Quality Planning Purposes, Federal Register, 

Volume 58, December 21, 1993, p. 67334. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-1 

4. EMISSIONS INVENTORY 

4.1 Introduction to Emissions Inventory 

An emissions inventory is an account of pollutant emissions that estimates the amount 

of air pollutants emitted from many sources. It is a starting point used in air quality 

modeling and attainment demonstrations. 

Although it is impractical to directly measure and compile emissions from a multitude of 

sources on a continuous basis, surveys and sampling may be used to increase 

understanding. For example, actual emission measurements are taken on a subset of 

devices to determine an average emission rate, source tests at stationary emission 

sources provide a snapshot of emission rates that are then be applied over time, and 

field measurements of fugitive dust emissions taken at area sources (such as 

construction sites) are used to determine an average emission rate under a variety of 

conditions. 

Emission factors, representative values that relate the quantity of emitted pollutants to 

an associated activity, may be developed by using the methods mentioned above, and 

are used to determine the total emissions. These factors are multiplied by activity and 

control factors to estimate emissions from sources. 

For this emissions inventory, 2008 is the base year, the year from which the inventory is 

projected forward and backward. This baseline year is the year from which rate of 

progress calculations, control measure development, and other calculations are based. 

More detailed information and emissions inventory tables are provided in Appendix A – 

Emissions Inventory. 

4.2 Emissions Inventory Requirements 

Emissions are updated as part of the overall requirement for “plan revisions to include a 

comprehensive, accurate, current inventory of actual emissions from all sources of the 

relevant pollutants” under sections 172(c)(3) and 182(a)(1) of the Clean Air Act. 

4.3 Precursors to PM10

This maintenance plan includes an emissions inventory for total primary PM10 and NOX

as a PM10 precursor. An analysis of inventories from the California Air Resources Board 

(CEFS Version 1.06 Sacramento Metropolitan AQMD, Rf#980) along with Chemical 

Mass Balance (CMB) modeling analysis (Motallebi, 1999) indicate that emissions of 

sulfur oxides (SOX) from Sacramento County sources are an insignificant contributor to 

secondary particulate formation. Adjusting for the past decrease in SOX emissions, 

current ambient ammonium sulfate concentrations are estimated to be about 1 μg/m3

. 

Therefore, SOX emissions are not included in this chapter. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-2 

4.4 Emissions Inventory Source Categories 

Due to the large number and wide variety of emission processes and sources, a 

hierarchical system of emission inventory categories was developed for more efficient 

use of the data. The anthropogenic (man-made) emissions inventory is divided into four 

broad categories: stationary sources, area-wide sources, on-road mobile sources, and 

other mobile sources. Each of these major categories is subdivided into more 

descriptive subcategory sources. Each of these subcategories is further defined into 

more specific emission processes. 

4.4.1 Stationary Sources 

The stationary source category of the emissions inventory includes non-mobile, fixed 

sources of air pollution. They are mainly comprised of individual, industrial, 

manufacturing, and commercial facilities called “point sources.” The more descriptive 

subcategories include fuel combustion (e.g. electric utilities), waste disposal (e.g. 

landfills), petroleum production and marketing, and industrial processes (e.g. mineral). 

Industrial facility operators reported the process and emissions data used to calculate 

emissions from point sources. 

4.4.2 Area-Wide Sources 

The area-wide sources inventory category includes aggregated emissions data from 

processes that are individually small and widespread or not well-defined point sources. 

The area-wide subcategories include residential fuel combustion, farming operations, 

construction and demolition activities, and road dust. Emissions from these sources are 

calculated from fuel usage, product sales, population, employment data, and other 

parameters for a wide range of activities that generate air pollution across Sacramento 

County. More detailed information on the area-wide source category emissions can be 

found on the CARB website: 

http://www.arb.ca.gov/ei/areasrc/areameth.htm. 

4.4.3 On-Road Motor Vehicles 

The on-road motor vehicles inventory category consists of trucks, automobiles, buses, 

and motorcycles. EMFAC, the California model for on-road motor vehicle emissions, 

has undergone significant revision since the EMFAC2002 model (version 2.2). As 

discussed below, this analysis relies on updated model parameters. 

Improved Motor Vehicle Emissions Model, EMFAC2007 

The California Air Resources Board has continued to update and improve its EMFAC 

on-road motor vehicle emissions model with extensive new data. CARB’s EMFAC2007 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-3 

model (version 2.3) was released November 2006. The most significant improvements 

in EMFAC2007 include: 

 Revised vehicle fleet information based on California Department of Motor Vehicles 

registration records specific to each county, which reflect the growth in vehicle 

populations and the increasing average age of the fleet; 

 Current base year and forecast year VMTs and speed distributions from regional 

transportation and metropolitan planning organizations; 

 Redistribution of heavy-duty diesel truck populations based on VMT; 

 Enhanced emission rate data for heavy-duty diesel trucks that include the results of 

testing larger sample sizes and recent model years; and 

 New temperature and relative humidity profiles better representing the meteorological 

conditions corresponding to air pollution problems. 

EMFAC software and detailed information on the vehicle emission model can be found 

on the CARB website: http://www.arb.ca.gov/msei/onroad/on-road.htm. 

Vehicle Activity Data 

On-road motor vehicle emission estimates for this plan were developed using the latest 

available transportation data and California’s new EMFAC2007 model6. The current and 

forecasted vehicle miles traveled (VMT) are from SACOG-supplied activity data 

(submitted to CARB July 2010)7 based on transportation modeling prepared for the 

Sacramento region’s August 2009 MTIP analysis. 

4.4.4 Other Mobile Sources

The emission inventory category for other mobile sources includes aircraft, trains, boats, 

and off-road vehicles and equipment used for construction, farming, commercial, 

industrial, and recreational activities. The OFFROAD2007 model was released 

November 2006 by CARB and used to calculate the air pollution emissions from offroad vehicles and equipment. In general, emissions are calculated based on estimated 

equipment population, engine size and load, usage activity, and emissions factors. 

Aircraft, boat, and train emissions are estimated outside the OFFROAD model. More 

detailed information on the OFFROAD 2007 mobile emissions model can be found on 

the CARB website: http://www.arb.ba.gov/msei/offroad/offroad.htm

 

6

 ARB conducted off model runs to incorporate SACOG’s regional travel demand model forecasts 

prepared for the August 2009 MTIP analysis that were not included in the released EMFAC2007 model 

(version 2.3). 

7

 SACOG (Griesenbeck) e-mail transmitting travel data to CARB (Wade) and SMAQMD (Anderson) on 

July 12, 2010. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-4 

4.5 Base Year Emissions and Forecasts 

4.5.1 Anthropogenic Emissions Tables by Source Category 

In Sacramento County, violations of the 24-hour PM10 NAAQS have only occurred 

during late November and December. These peak concentrations typically occur due to 

wintertime weather conditions (e.g., atmospheric stability, low wind dispersion, and 

colder temperatures) conducive to PM10 pollutant build up in conjunction with increased 

secondary formation of particulates and more residential wood combustion activities. 

Therefore, emissions inventories for PM10 and NOX are compiled for an average winter 

day. Emissions of volatile organic compounds (VOC) and sulfur oxides (SOX) are 

considered to be insignificant contributors to the formation of PM10 in Sacramento 

County, based on previous CMB analyses (see page 3-11). 

The following tables (Table 4.1 and 4.2) show the anthropogenic emissions inventory of 

PM10 and NOX by source categories for Sacramento County. The emissions inventory is 

shown for average winter day in units of tons per day. Inventories were obtained from 

the California Air Resources Board (CARB) on September 3, 2010 for the years 2008, 

2012, and 2022.8 

 

8

 CARB (Ruiz) e-mail transmitting emissions inventory data for the Sacramento PM10 Maintenance Plan to 

SMAQMD (Tollstrup) on September 3, 2010. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-5 

Table 4.1 

PM10 Emissions (tons per day) 

Sacramento County 

 AVERAGE WINTER DAY INVENTORY 2008 2012 2022 

 

TOTAL EMISSIONS 35 35 36 

 STATIONARY 1 1 2 

 AREAWIDE 30 30 31 

 ON-ROAD MOTOR VEHICLES 2 2 2 

 OTHER MOBILE 1 1 1 

 

STATIONARY 

 Fuel Combustion 0.5 0.5 0.6 

 Industrial Processes 1.0 0.9 1.1 

 

AREAWIDE 

 Residential Fuel Combustion 9.9 9.2 10.2 

 Farming Operations 2.4 2.3 2.1 

 Construction and Demolition 7.0 7.2 7.8 

 Paved Road Dust 6.1 6.2 6.4 

 Unpaved Road Dust 3.6 3.6 3.6 

 Other 1.2 1.3 1.4 

 

ON-ROAD MOTOR VEHICLES 2.2 2.1 2.1 

 

OTHER MOBILE 

 Aircraft 0.1 0.1 0.1 

 Trains 0.1 0.1 0.1 

 Boats 0.1 0.1 0.1 

 Equipment (Off-Road/Farm) 1.1 1.0 0.4 

Data Source: CARB (Ruiz) e-mail transmitting emissions inventory data for the Sacramento PM10

Maintenance Plan to SMAQMD (Tollstrup) on September 3, 2010. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-6 

Table 4.2 

NOX Emissions (tons per day) 

Sacramento County 

 AVERAGE WINTER DAY INVENTORY 2008 2012 2022 

TOTAL EMISSIONS 82 67 42

 STATIONARY 4 4 4 

 AREAWIDE 4 4 4 

 ON-ROAD MOTOR VEHICLES 50 38 18 

 OTHER MOBILE 24 21 15 

STATIONARY 

 Fuel Combustion 3.9 4.0 4.2 

 Industrial Processes 0.1 0.1 0.1 

AREAWIDE 

 Residential Fuel Combustion 4.4 4.3 4.4 

 Managed Burning and Disposal 0.1 0.1 0.1 

ON-ROAD MOTOR VEHICLES 49.6 37.6 18.1 

OTHER MOBILE 

 Aircraft 2.0 2.3 3.0 

 Trains 3.4 3.3 3.6 

 Boats 0.5 0.5 0.5 

 Off-Road Equipment 16.0 13.6 7.6 

 Farm Equipment 1.8 1.4 0.6 

Data Source: CARB (Ruiz) e-mail transmitting emissions inventory data for the Sacramento PM10

Maintenance Plan to SMAQMD (Tollstrup) on September 3, 2010. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-7 

4.5.2 2008 Base Year Emissions Distribution 

The following pie chart (Figure 4.1) shows the 2008 PM10 emission inventory categories 

as a percentage of the total inventory for Sacramento County. In 2008, the PM10

inventory was mainly comprised of area-wide sources – Paved Road Dust, Residential 

Fuel Combustion, and Construction & Demolition. 

Figure 4.1 

2008 PM10 Emissions Distribution 

Sacramento County 

35 Tons Per Day (avg. winter day) 

Off-Road Equipment

3%

Stationary Sources

4%

Other Areawide Sources

3%

Other Mobile Sources

7%

Unpaved Road Dust

10%

Paved Road Dust

17%

Construction & Demolition

20%

Farming Operations

7%

Residential Fuel 

Combustion

29%

Data Source: CARB (Ruiz) e-mail transmitting emissions inventory data for the Sacramento PM10

Maintenance Plan to SMAQMD (Tollstrup) on September 3, 2010. 

The main contribution of NOX emissions comes from on-road motor vehicles and then 

other mobile sources. In 2008, on-road motor vehicles accounted for about 60% of the 

NOX inventory, and other mobile sources contributed almost 30%. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-8 

4.6 Analysis of Emissions Inventory Forecasts 

Figure 4.2, shows that between 2008 and 2022, combined values of PM10 and NOX

emissions are expected to steadily decline from 117 tons per day down to 78 tons per 

day, for a 33% decrease. 

Figure 4.2 

PM10 & NOX Emissions and Forecasts 

Sacramento County 

0

20

40

60

80

100

120

140

2008 2012 2022

Year

tons per day

NOx PM10

Data Source: CARB (Ruiz) e-mail transmitting emissions inventory data for the Sacramento PM10

Maintenance Plan to SMAQMD (Tollstrup) on September 3, 2010 for average winter day. 

An examination of the inventory forecast indicates that the three largest categories of 

primary PM10 will continue to be paved road dust, residential fuel combustion, and 

construction & demolition. Table 4.3 shows that between 2008 and 2022, these subcategories of primary PM10 are expected to increase. 

Table 4.3 

Major Categories of PM10 Expected Increase 

Sacramento County for 2008-2022 

PM10 Inventory 

Category Paved Road Dust Residential Fuel 

Combustion 

Construction & 

Demolition 

Tons Per Day 2008 2022 2008 2022 2008 2022 

6.12 6.35 9.91 10.24 7.01 7.76 

Percent Increase 4% 3% 11% 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-9 

The increase in paved road dust is forecasted to correlate to the increase in centerline 

road miles. The increase in residential fuel combustion PM10 is estimated by 

assumptions on population growth and the effectiveness of residential wood burning 

control measures. The PM10 emissions increase from construction & demolition 

activities is related to the expected growth in population and economic development. 

The NOX emissions inventory forecast indicates a steady decline due to emission 

controls, despite expected increases in population and vehicle miles traveled (VMT). 

Between 2008 and 2022, NOX emissions from on-road motor vehicles are estimated to 

emit 50 tons per day down to 18 tons per day, for a 64% decrease. Other mobile source 

NOX emissions decline from 24 tons per day down to 15 tons per day, for a 37% 

decrease. 

Figure 4.3 illustrates trends in population and VMT. Between 2008 and 2022, population 

and VMT in Sacramento County are expected to increase by 24% and 21%, 

respectively. 

Figure 4.3 

Population and Vehicle Miles Traveled (VMT) Forecasts 

Sacramento County (1990-2035) 

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

2.00

1990 1995 2000 2005 2010 2015 2020 2025 2030 2035

YEAR

Population (million) 

0

10000

20000

30000

40000

50000

60000

VMT (Thousands of miles per day)

Population VMT

Data sources: 

1. SACOG household population forecasts are from SACOG’s Tina Glover 7-3-08 email. Data are 

derived from the December 2007 SACSIM travel model. 

http://www.arb.ca.gov/app/emsinv/trends/ems_trends_results.php

2. 2005 to 2035 VMT data are based on SACSIM regional travel demand model forecasts for SACOG’s 

August 2009 MTIP analysis (submittal to CARB, June 2010). Pre-2005 VMT data are from CARB 

EMFAC2007 model runs (version 2.3). 

3. Yearly values not given in either SACOG report are interpolated. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-10 

4.7 General Conformity and Airport Emissions Inventory 

General conformity is the federal regulatory process for preventing major federal 

actions9

 or projects from interfering with air quality planning goals. Conformity provisions 

ensure that federal funding and approval are given only to those activities and projects 

that are consistent with state air quality implementation plans (SIPs). Conformity with 

the SIP means that major federal actions will not cause new air quality violations, 

worsen existing violations, or delay timely attainment of the national ambient air quality 

standards (NAAQS). 

Current federal rules require that federal agencies use the emissions inventory from an 

approved SIP’s attainment or maintenance demonstration to support a conformity 

determination. The emissions inventory in this PM10 implementation/maintenance plan 

may be used for general conformity purposes. A specific inventory for airport emissions 

is provided for the potential general conformity analysis of future airport expansions. 

Sacramento County has prepared a master plan for future growth in airport activities 

that shows an increase in emissions. The Sacramento County Airport System is 

comprised of four airports: Sacramento International (SMF), Mather (MHR), Executive 

(SAC), and Franklin (F32). In addition, the County Airport System manages the aviation 

activities at McClellan Airport on behalf of another County agency. Three private 

airports also operate in Sacramento County: Rancho Murieta, Rio Linda, and Sunset.10

To facilitate future conformity determinations, the emissions from growth in airport 

activities are estimated for 2012 and 2022. The PM10 and NOX airport emissions 

forecasts associated with aircraft operations and ground support equipment in 

Sacramento County are provided in Table 4.4. This table reflects elementary 

mathematical rounding convention to nearest tenths, for example 0.25 or greater is 0.3 

and 0.24 or less is 0.2. Numbers less than 0.05 are rounded up to 0.1 to avoid the 

erroneous impression that the emissions are zero.

 

9

 Federal actions are defined as any activity engaged in by a department, agency, or instrumentality of the 

Federal government, or any activity that they support, fund, license, permit, or approve, other than 

activities related to transportation plans, programs, and projects that are applicable to transportation 

conformity requirements. (40 CFR 93.152) 

10 Information from Sacramento County Airport System; comment letter dated October 24, 2008. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-11 

Table 4.4 

Airport (Aircraft Operations + Ground Support Equipment) Emissionsa

for Sacramento County Only 

Year Operations PM10 (tons/day) NOX (tons/day) 

2012 Aircraft Operations Only 0.1 2.3 

Ground Support Equipment 0.1 0.3 

2022 Aircraft Operations Only 0.2 0.1 3.0 

 Ground Support Equipment 0.1 0.2 

a

 Data Source: CARB CEFS Version 1.06 Sacramento Metropolitan AQMD (Rf#980), February 28, 2007, 

for average winter day. 

4.8 Emission Reduction Credits 

Certain pollutant emission reductions due to equipment shutdown or voluntary control 

may be converted to emission reduction credits (ERCs) and registered with the Air 

District. These ERCs may then be used as “offsets” to compensate for an increase in 

emissions from a new or modified major emission source regulated by the Air District. In 

the SMAQMD, ERCs may also be used as an alternative to strict compliance with 

specified rules. Thus, if a permitted source cannot meet the applicable emission 

standard requirements, usually because it is technically infeasible or not cost effective, 

the source may lease or purchase ERCs to achieve the required reductions. 

Since ERCs represent potential emissions, they need to be taken into account in the 

emission inventories. One method is to assume that the use of ERCs will already be 

included within the projected rate of stationary source growth in the emissions inventory. 

However, if the use of available ERCs exceeds anticipated emissions growth, future 

emissions could be underestimated. Therefore, to ensure that the use of ERCs will not 

be inconsistent with the future PM10 maintenance goals, the amount of ERCs issued for 

reductions that occurred prior to the 2008 base year are added to the emission 

inventory forecasts in the maintenance demonstration. 

Pre-2008 Emission Reduction Credits 

For this PM10 maintenance plan, the amounts of unused banked ERCs of emissions 

reductions that occurred prior to the 2008 baseline year in Sacramento County are 

listed in Table 4.5. The ERCs consist of emissions reduced from stationary sources and 

military aircraft. Including these ERCs here simply maintains the validity of previously 

banked ERCs and other reductions. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-12 

Future Bankable Rice Burning Emission Reduction Credits 

California legislation11 in 1991 (known as the Connelly bill) required rice farmers to 

phase down rice field burning on an annual basis, beginning in 1992. A burn cap of 

125,000 acres in the Sacramento Valley Air Basin was established, and growers with 

400 acres or less were granted the option to burn their entire acreage once every four 

years. Since the rice burning reductions were mandated by state law, they would 

ordinarily not be “surplus” and eligible for banking. However, the Connelly bill included a 

special provision declaring that the reductions qualified for banking if they met the State 

and local banking rules. 

Reductions in rice burning may be banked in the future under an ERC rule12 currently in 

development. The total amounts of potential bankable rice burning ERCs in Sacramento 

County are summarized in Table 4.5. 

Available Wood Stove/Fireplace Change Out Incentive Program Emission Reduction 

Credits 

The Wood Stove/Fireplace Change Out Incentive Program was established in June 

2006 to provide financial incentives to remove or replace existing fireplaces and dirty 

wood stoves. About half of the emission reductions from this program will be available 

for the ERC bank. These potential ERCs from the Wood Stove/Fireplace Change Out 

Incentive Program are summarized in Table 4.5. 

Summary of Emission Reduction Credits 

ERCs issued for reductions that occurred prior to the 2008 base year and potential 

future bankable ERCs from rice burning and Wood Stove/Fireplace Change Out 

Incentive Program are summarized for Sacramento County in Table 4.5. These ERCs 

are in tons per day for average winter day and will be included in the PM10 maintenance 

demonstration. 

 

11 Connelly-Areias-Chandler Rice Straw Burning Reduction Act of 1991, section 41865 of California 

Health and Safety Code. 

12 This rice burning ERC rule must be approved by EPA into the SIP for the rice ERCs to be used for 

compliance with federal air quality requirements. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Emissions Inventory 

Page 4-13 

Table 4.5 

Emission Reduction Credits Added to the Maintenance Demonstration 

Sacramento County 

Emissions in tons/day (avg. winter day) PM10 NOX SOX

Pre-2008 Emission Reduction Credits 0.081 1.469 0.222 

Future Bankable Rice Burning Emission Reduction 

Credits 0.109 0.090 0.019 

Wood Stove/Fireplace Change Out Incentive 

Program 0.067 0.004 0.001 

Total ERCs 0.257 1.563 0.242 

Total ERCs (rounded up) 0.3 1.6 0.3 

4.9 Emissions Inventory Documentation 

More detailed tables of the PM10 and NOX emissions inventory are provided in Appendix 

A. This appendix contains the estimated 2008, 2012, and 2022 emissions inventory for 

Sacramento County. 

Emission inventories are constantly being updated to incorporate new and better 

information and methodologies. Detailed information on emission methodologies, 

changes and forecasts can be found on CARB websites: http://www.arb.ca.gov/ei/ei.htm

and http://www.arb.ca.gov/msei/msei.htm

4.10 Emissions Inventory Conclusions 

The emissions inventory is an account of pollutant emissions that estimates the amount 

of air pollutants emitted from many sources. This maintenance plan includes an 

emissions inventory for total primary PM10 and NOX as a PM10 precursor. 2008 is the 

base year, the year from which the inventory is projected forward. An examination of the 

emissions inventory indicates that the three largest categories of primary PM10 are the 

area-wide sources for paved road dust, residential fuel combustion, and construction & 

demolition, while mobile source categories contribute over 85% of the NOX emissions 

inventory. Between 2008 and 2022, total PM10 emissions are expected to increase 2-3% 

and NOX emissions are expected to steadily decrease by 48%, despite increasing 

vehicle miles traveled and population in Sacramento County. The combined inventory of 

PM10 and NOX precursors is projected to decline about 33%. 

4.11 References 

Motallebi, Nehzat. Wintertime PM2.5 and PM10 Source Apportionment at Sacramento 

California. Air and Waste Management Association 1999: 25-34. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Control Measures 

Page 5-1 

5. CONTROL MEASURES 

5.1 Introduction to Control Measures 

This chapter briefly describes the control measure requirements and identifies the 

appropriate control measures that enabled Sacramento County to attain the PM10

NAAQS and also provide for maintenance of the standard. The control strategy includes 

a combination of actions taken by local, state, and federal agencies to reduce PM10 and 

applicable PM10 precursor emissions from various source categories. Control measures 

are developed and adopted into regulatory rules and programs, which are then 

implemented, monitored, and enforced. No new control measure commitments are 

included in this plan since the existing control strategy is predicted to maintain the PM10

NAAQS throughout the future 10-year maintenance period. 

5.2 Control Measure Requirements 

Sections 172(c)(1) and 189(a)(1)(C) of the Clean Air Act require that PM10

nonattainment area plans include provisions to ensure that reasonably available control 

measures (RACM) are implemented, including, at a minimum, the adoption of 

reasonably available control technology (RACT). Section 189(e) of the Clean Air Act 

requires control requirements that apply to major stationary sources of PM10 also apply 

to major stationary sources of PM10 precursor pollutants. 

However, the RACM and RACT requirements make certain allowances. EPA will allow 

rejection of any of the RACM, provided it can be shown that emissions from the sources 

affected do not contribute significantly to PM10 levels which exceed the NAAQS 

(Calcagni, 1991, p.7). Also, a SIP can commit to less than all the available measures 

when attainment and RFP requirements have been adequately and appropriately 

demonstrated or already achieved. Thus, where an area is already attaining the 

standard, no additional RACM measures are required (71 FR 27444). 

EPA provided a list of certain RACM measures in the General Preamble to Title I of the 

Clean Air Act that were suggested for incorporation into a PM10 SIP (57 FR 13498). 

These EPA-established RACM for PM10 control strategies include: 

1. Fugitive dust control measures, 

2. Residential wood combustion control measures, and 

3. Prescribed burning control measures. 

5.3 RACM/RACT Evaluation 

Since EPA determined that Sacramento County already attained the PM10 NAAQS, 

RACM requirements are suspended under EPA’s Clean Data Policy. Therefore, no 

additional RACM measures are required. Rules previously adopted prior to the 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Control Measures 

Page 5-2 

nonattainment designation period and control measures that were implemented 

afterwards and brought the nonattainment area into attainment are identified. 

Fugitive Dust Control Measures 

Fugitive dust is particulate matter suspended in the air either by mechanical disturbance 

of the surface material or by wind action blowing across the surface. RACM for fugitive 

dust primarily focuses on stabilizing the particulate on the road surface, or eliminating 

the particulate. Several RACM measures have already been adopted in the past, and 

are currently being enforced in the Sacramento area. An example is the California 

Vehicle Code (23114) which requires that haul trucks cover their load or maintain 

adequate freeboard. This plan does not include any fugitive dust control measures 

above those already in place. The SMAQMD proposes to evaluate additional RACM 

PM10 measures as potential contingency plan measures. 

The following District measures were previously implemented to reduce fugitive dust 

emissions: 

Rule Number and Topic Date Initially Adopted 

 Rule 401 Ringelmann Chart/Opacity 8-3-77 

 Rule 403 Fugitive Dust 8-3-77 

 Rule 404 Particulate Matter 3-11-70 

 Rule 405 Dust and Condensed Fumes 8-1-62 

Residential Wood Combustion Control Measures 

Incomplete combustion in residential wood stoves and fireplaces can lead to elevated 

PM10 concentrations. The residential wood combustion control measures are intended 

to reduce emissions from existing stoves and fireplaces through inspections, education, 

shifting to cleaner fuels, voluntary or mandatory curtailment of burning during 

meteorological conditions which trap particulates (such as stagnant air and inversions), 

and limit the future growth of wood combustion emissions. The highest recorded PM10

levels in the county have occurred during the winter months when stagnation and 

inversions were evident. 

The following District measures were implemented to reduce residential wood 

combustion emissions. These measures were adopted after attaining the federal PM10

standard and will help in maintaining the standard. 

 The Wood Stove/Fireplace Change Out Incentive Program was established in June 

2006 to provide financial incentives to remove or replace existing fireplaces and dirty 

wood stoves. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Control Measures 

Page 5-3 

 Rule 417, Wood Burning Appliances, was approved by the Board of Directors on 

October 26, 2006 to prohibit installing new fireplaces and dirty wood burning 

devices. 

 Rule 421, Mandatory Episodic Curtailment of Wood and Other Solid Fuel Burning, 

was adopted on October 25, 2007 to restrict wood burning on forecasted high PM2.5

days during November through February. It was amended on September 24, 2009 to 

tighten the forecast thresholds for burning restrictions. Emission reductions from 

Rule 421 were included in the emission inventory projections used in the 

maintenance demonstration. 

 The Spare The Air public education program has incorporated ambient PM2.5 air 

pollution awareness and AQI forecasting during November through February. 

Prescribed Burning Control Measures 

EPA suggests that a prescribed burning program include the following elements: 

 smoke dispersion evaluation 

 burn planning, authorization, and administration 

 requirements to ensure burner qualifications 

 public education and awareness 

 surveillance and enforcement 

 emissions inventories and emission efforts 

 state oversight 

The existing District Rule 501 – Agricultural Burning (initially adopted September 13, 

1971) is equivalent to these specifications and meets the RACM requirements for 

prescribed burning. In addition, Sacramento County is included in the Sacramento 

Valley Air Basin Smoke Management Program13 which ensures that agricultural burning 

is prohibited on days meteorologically conducive to potentially elevated PM10

concentrations. 

Other Burning Control Measures 

The following District measures were previously implemented to reduce burning 

emissions: 

Rule Number and Topic Date Initially Adopted 

 Rule 407 Open Burn 3-11-70 

 Rule 408 Incinerator Burning 3-11-70 

 Rule 409 Orchard Heaters 5-15-72 

 

13 Specifics can be found in the “Smoke Management Guidelines for Agricultural and Prescribed Burning,” 

CARB, May 14, 2001. Title 17 California Code of Regulations, Subchapter Z, Section 80100 et. seq. 

<http://www.arb.ca.gov/smp/regs/RevFinRegwTOC.pdf> 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Control Measures 

Page 5-4 

Sulfur Dioxide Control Measures 

The following District measures were previously implemented to reduce sulfur dioxide 

emissions: 

Rule Number and Topic Date Initially Adopted 

 Rule 406 Specific Contaminants 3-11-70 

 Rule 420 Sulfur Content of Fuels 8-3-77 

RACT Measures 

Reasonably available control technology (RACT) is the lowest emission limitation that a 

particular source is capable of meeting by the application of control technology that is 

“reasonably available” considering technological and economic feasibility. RACT applies 

to existing stationary sources, and EPA recommends that major stationary sources be 

the minimum starting point for RACT analysis (Calcagni, 1991). Generally, it is 

recommended that RACT be applied to existing sources in the nonattainment area that 

are reasonable to control, based on the attainment needs of the area. 

SMAQMD’s various fugitive dust and combustion restriction rules have been applied to 

major stationary sources within Sacramento County to reduce PM10 emissions and meet 

RACT requirements. However, PM10 emissions from existing stationary sources only 

add up to less than 2% of the total emissions inventory of PM10 and NOX. 

In addition to RACT for major PM10 stationary sources, CAA Section 189(e) suggests 

that moderate PM10 nonattainment areas apply RACT for major stationary sources of 

PM10 precursors, unless EPA determines such sources do not contribute significantly to 

PM10 exceedance levels (Calcagni, 1991). The District has applied RACT rules to 

existing NOX sources. The NOX RACT evaluations of reduction measures were 

completed to satisfy ozone nonattainment mandates (SMAQMD, 2006) (SMAQMD, 

2008). The evaluation/demonstration satisfies the RACT requirements for PM10 required 

due to the secondary formation of atmospheric ammonium nitrates, which are a 

significant component of PM10 concentrations in the Sacramento area. 

The following District control measures to reduce NOX emissions from existing 

stationary sources were implemented: 

 Rule 411 – NOX from Boilers, Process Heaters, and Steam Generators (initially 

adopted 2-2-95) 

 Rule 412 – Stationary Internal Combustion Engines at Major Stationary Sources of 

NOX (initially adopted 6-1-95) 

 Rule 413 – Stationary Gas Turbines (initially adopted 4-6-95) 

 Rule 414 – Natural Gas Fired Water Heaters (initially adopted 8-1-96) 
PM10 Implementation/Maintenance Plan and 

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Control Measures 

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State Control Measures 

Several emission reduction programs have been implemented by the California Air 

Resources Board (CARB) to reduce directly emitted particulates and secondary PM 

precursor pollutants (NOX and SOX). These measures primarily address cleaner fuel 

specifications for diesel and reformulated gasoline, and mobile source engine emission 

standards that CARB has implemented statewide. 

5.4 New Source Review Program 

Sections 172(c)(5) and 189(a)(1)(A) of the Clean Air Act require the SIP to include 

provisions for a new source review (NSR) program to require permits for the 

construction and operation of new or modified major stationary sources anywhere in the 

nonattainment area, in accordance with Section 173, Permit Requirements. The term 

major stationary sources for a PM10 “moderate” nonattainment classification means any 

stationary source which directly emits, or has the potential to emit, 100 tons per year or 

more of PM10. NSR requirements also apply to major stationary sources of PM10

precursors. The proposed sources are required to comply with the lowest achievable 

emission rate. 

The District’s New Source Review Rule (Rule 202) requires that all new or modified 

sources of PM10, nitrogen oxides, sulfur oxides, or reactive organic compounds apply 

best available control technology (BACT) to control those emissions. Rule 202 

requirements meet or are more stringent than those required for a moderate 

nonattainment area and therefore satisfy the Clean Air Act’s NSR permit program 

requirement. The Calcagni memo states that, “the Part D new source review program 

will be replaced by the prevention of significant deterioration (PSD) program once the 

area has been redesignated” (Calcagni, 1992). Rule 203 – Prevention of Significant 

Deterioration will be implemented after EPA redesignates Sacramento County to 

attainment. 

5.5 Control Measures Conclusions 

The SMAQMD has adopted and implemented a number of PM control measures to 

reduce emissions from fugitive dust, wood burning devices, and agricultural burning. In 

addition, the SMAQMD has applied RACT rules to existing PM10 and NOX sources, 

which will directly reduce fugitive dust, combustion particulates, and the secondary 

formation of atmospheric ammonium nitrates, a significant component of PM10

concentrations in the Sacramento area. Several emission reduction programs have also 

been implemented by the California Air Resources Board (CARB) to reduce directly 

emitted particulates and secondary PM precursor pollutants (NOX and SOX) from mobile 

sources. These measures primarily address cleaner fuel specifications for diesel and 

reformulated gasoline, and mobile source engine emission standards that CARB has 

implemented statewide. No new control measure commitments are included in this plan 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Control Measures 

Page 5-6 

since the existing control strategy is predicted to maintain the PM10 NAAQS throughout 

the future 10-year maintenance period. 

5.6 References 

Calcagni, John. PM-10 Moderate Area SIP Guidance: Final Staff Work Product, Air 

Quality Management Division, EPA, April 2, 1991. 

Calcagni, John. Procedures for Processing Requests to Redesignate Areas to 

Attainment, Air Quality Management Division, EPA, September 4, 1992, p. 6. 

SMAQMD. Analysis of Reasonably Available Control Technology for the 8-Hour Ozone 

State Implementation Plan (RACT SIP) Staff Report, September 26, 2006. 

SMAQMD. Updated Analysis of Reasonably Available Control Technology for the 8-

Hour Ozone State Implementation Plan (Updated RACT SIP) Staff Report, 

September 22, 2008. 

USEPA. General Preamble for the Implementation of Title I of the Clean Air Act 

Amendments of 1990, Appendix C, Federal Register, Volume 57, April 16, 1992, 

p. 13498. (http://www.epa.gov/ttn/oarpg/t1pfpr.html) 

USEPA. Approval and Promulgation of Air Quality Implementation Plans; West Virginia; 

Redesignation of the City of Weirton PM-10 Nonattainment Area to Attainment 

and Approval of the Maintenance Plan, Federal Register, Volume 71, May 11, 

2006, p. 27440-27447. 
PM10 Implementation/Maintenance Plan and 

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Maintenance Demonstration 

Page 6-1 

6. MAINTENANCE DEMONSTRATION 

6.1 Introduction to Maintenance Demonstration 

The maintenance demonstration is a key element in a SIP maintenance plan that shows 

future compliance of the national ambient air quality standard (NAAQS) will continue to 

be achieved. This chapter describes the basic requirements for a maintenance 

demonstration, provides a maintenance demonstration analysis, and discusses 

methods for implementing verification and tracking procedures. 

6.2 Maintenance Demonstration Requirements 

Section 175A of the Clean Air Act (CAA) contains planning requirements pertaining to 

the general framework of a maintenance plan. These requirements include a 

maintenance demonstration to provide for maintenance of the NAAQS for at least 10 

years after redesignation is approved by EPA (not 10 years after submittal of a 

redesignation request). Therefore, the maintenance planning period also must factor in 

time necessary for EPA review and approval action on the redesignation request. 

Section 107(d)(3)(D) allows EPA up to 18 months from receipt of a complete submittal 

to process a redesignation request. Since this maintenance plan and redesignation 

request are being submitted simultaneously in 2010, the maintenance planning years 

are from 2012 to 2022. 

Section 175A also specifies that the maintenance plan shall contain such additional 

measures, if any, as may be necessary to ensure such maintenance. In 1992, EPA 

issued additional discussion, clarification and guidance on requirements for 

redesignation requests and maintenance plans (Calcagni, 1992). This Calcagni 

memorandum included the following additional provisions needed for a maintenance 

demonstration plan: 

 Maintenance demonstration of the NAAQS either by showing that future emissions 

will not exceed the attainment level or by modeling to show future emissions will not 

cause a violation of the standard. 

 Verification of continued attainment through operation of an appropriate air quality 

monitoring network. 

 Tracking the progress of the maintenance demonstration by a periodic review or 

update of the factors and assumptions used in the maintenance demonstration. 

6.3 Maintenance Demonstration Analysis 

The maintenance demonstration must show that the future mix of sources and emission 

rates, when combined with implemented control strategies during the 10-year 

maintenance planning period, will not cause any violations of the NAAQS. The method 

used for the maintenance demonstration is performed by proportional rollback modeling 

to show that future emissions will not cause a violation of the 24-hour PM10 NAAQS 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Maintenance Demonstration 

Page 6-2 

(150 μg/m3). The premise of proportional rollback is that the change in individual 

pollution sources are directly proportional to the change in associated ambient 

concentrations due to that individual source as determined by receptor modeling using 

the Chemical Mass Balance (CMB) model. 

Four steps were taken to demonstrate maintenance of the 24-hour PM10 NAAQS. 

Step 1: PM10 and Precursor Emissions Source Inventories 

Table 6.1 contains the emissions source inventories for PM10 and secondary PM10

precursor pollutants for 1995, 2008, 2012, and 2022. Emission reduction credits 

(described in Section 4.8) are added to the 2012 and 2022 emission forecasts to ensure 

their use will not be inconsistent with the PM10 maintenance demonstration. 

The additional increase in 1.0 ton per day of PM10 to Paved Road Dust and 0.5 ton per 

day of PM10 to Road Construction Dust in the 2022 transportation budgets are 

accounted for in the maintenance demonstration emission forecasts for Fugitive Dust 

PM10. The additional increase in the 2008, 2012, and 2022 NOX and PM10 transportation 

budgets due to rounding up to the nearest ton are also accounted for in the 

maintenance demonstration emission forecasts for Total NOX and Fugitive Dust PM10. 

The PM10 and precursor emissions source inventory categories are assumed to directly 

impact the matching CMB ambient PM10 speciation categories for projection purposes in 

Step 2. For example, as shown in the following table, Total NOX emissions are matched 

to CMB ambient Ammonium Nitrate concentrations. 

 

Category 

No. 

Emissions Source Category CMB Ambient Source 

Category 

1. Total NOX Ammonium Nitrate 

2. Mobile Sources PM10 (all on-road and off-road mobile sources) Motor Vehicles PM10

3. Wood Burning PM10 (residential fuel combustion, fires, waste 

burning and disposal) 

Wood Smoke PM10

4. Fugitive Dust PM10 (mineral processes, farming operations, 

construction and demolition, paved road dust, unpaved road 

dust, and fugitive windblown dust) 

Fugitive Dust PM10

5. Total SOX Ammonium Sulfate 

6. Total PM10 (all direct PM10 emission source categories) Unidentified Other 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Maintenance Demonstration 

Page 6-3 

Table 6.1 

PM10 and Precursor Emissions Source Inventories 

Sacramento County 

 Emissions (tons/day, winter average) 

Emissions Source Category 1995* 2008 2012 2022 

1. Total NOX + 1.6 tpd ERCs 118.2 82.1 67.7 + 1.6 43.1 + 1.6 

2. Mobile Sources PM10 3.6 3.6 3.3 2.8 

3. Wood Burning PM10

** 10.2 10.2 9.5 10.5 

4. Fugitive Dust PM10 17.8 20.2 20.4 22.8 

5. Total SOX*** + 0.3 tpd ERCs 2.2 0.6 0.7 + 0.3 0.7 + 0.3 

6. Total PM10 + 0.3 tpd ERCs 33.0 35.2 34.5 + 0.3 35.9 + 0.3 

 *1995 source emissions are listed since 1991-1996 ambient monitoring data used for CMB modeling analysis. 

 **Reflects mandatory episodic wood burning restrictions (SMAQMD Rule 421) implemented Nov 2007. 

***SOX emissions obtained from CARB CEFS Version 1.06 winter average inventory. 

Step 2: Ambient PM10 Speciation Concentrations 

CMB receptor modeling results for 1991-1996 wintertime (Nov-Jan) ambient 24-hour 

PM10 samples (>40 μg/m3) were used to derive an average speciation profile to 

represent high value 1995 PM10 winter concentrations. However, the 1995 ambient 

PM10 speciation profile may have changed over time due to emission source inventory 

changes and may no longer reflect current ambient data. Therefore, the 1995 ambient 

PM10 speciation concentrations are forecasted to 2008 by applying the ratio of 

associated emissions source category changes listed in Step 1. 

Table 6.2 contains the 1995 CMB analysis concentration profile and the projected 

speciation adjustments to 2008. The percent adjustment is assumed linear at 1 to 1, 

except ammonium nitrate concentrations are assumed to change 0.7% for every 1% 

change in NOX emissions, based on evaluation of San Joaquin Valley Air Pollution 

Control District modeling results from their 2007 PM10 Maintenance Plan (SJVAPCD, 

2007). 
PM10 Implementation/Maintenance Plan and 

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Maintenance Demonstration 

Page 6-4 

Table 6.2 

Ambient PM10 Speciation Concentrations 

Sacramento County 

1995 CMB* 

Analysis 1995 

2008 

Projection 2008 Conc. 2008 

PM10 CMB Source Category (μg/m3) (% Total) Factor (μg/m3) (% Total) 

1. Ammonium Nitrate 14.9 28.9% 0.786 11.7 24.4% 

2. Motor Vehicles 11.8 22.9% 0.996 11.7 24.5% 

3. Wood Smoke 8.6 16.6% 0.997 8.5 17.8% 

4. Fugitive Dust 6.4 12.4% 1.135 7.3 15.1% 

5. Ammonium Sulfate 2.3 4.4% 0.277 0.6 1.3% 

6. Unidentified Other 7.6 14.7% 1.065 8.1 16.9% 

Total PM10 51.5 100.0% 48.0 100.0% 

*Average CMB speciation analysis of 1991-1996 wintertime (Nov-Jan) ambient 24-hour PM10 samples >40 (μg/m3) 

for 13th and T St. site assumed to represent 1995. 

Step 3: Speciated 2008 Base Peak PM10 Concentrations 

2008 base peak 24-hour PM10 concentrations are derived by applying the % total 

speciation categories to the recent peak PM10 monitored value of 109 μg/m3 (shown in 

Table 6.3). The 109 μg/m3

 represents the 2008 design (high) value for 24-hour PM10

concentrations monitored during 2006-2008 in Sacramento County. 

The PM10 monitoring data used to determine the design value concentrations are from 

the FRM filter based high-volume samplers. TEOM data samples were not used for this 

analysis due to potential inaccuracies during the winter time when there is wood 

combustion.14

Step 4: Predicted Future Peak 24-Hour PM10 from 2008 Base Peak 

Predicted peak 24-hour PM10 concentrations for 2012 and 2022 in Table 6.3 are 

estimated by using applicable emissions forecast changes (with ERCs) to project 2008 

base peak PM10 concentrations. The reduction in source contributions from motor 

vehicles and nitrates in future years is due to the existing emissions control strategies 

that have already been accounted for in the emissions forecast inventories. Increases in 

future wood smoke, fugitive dust, and sulfate concentrations can be attributed to 

population growth, the construction of more roads, and increasing fuel combustion. The 

unidentified other PM10 concentrations are forecasted using the change in total PM10

since their associated emission source categories are not known. 

 

14 The SMAQMD older model TEOM monitors contain a heater for reducing moisture, which can remove 

volatile compounds from ambient air samples, such as those in wood smoke. 
PM10 Implementation/Maintenance Plan and 

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Maintenance Demonstration 

Page 6-5 

Table 6.3 

Predicted Peak PM10 from “2008” Base Peak 

Sacramento County 

2008 

2008 

Peak 

Conc. 

2012 

Projection

2012 

Peak 

Conc. 

2022 

Projection 

2022 

Peak 

Conc. 

PM10 CMB Source Category (% Total) (μg/m3) Factor (μg/m3) Factor (μg/m3) 

1. Ammonium Nitrate 24.4% 26.6 0.891 23.7 0.681 18.1 

2. Motor Vehicles 24.5% 26.7 0.932 24.9 0.775 20.7 

3. Wood Smoke 17.8% 19.4 0.931 18.1 1.032 20.0 

4. Fugitive Dust 15.1% 16.5 1.010 16.7 1.129 18.6 

5. Ammonium Sulfate 1.3% 1.4 1.532 2.2 1.677 2.4 

6. Unidentified Other 16.9% 18.4 0.991 18.2 1.028 18.9 

Total PM10 100.0% 109* 104 99 

*109 μg/m3 was peak monitored value from 2006-2008 in Sacramento County (T Street, 2006)

6.4 Results of Maintenance Demonstration 

Overall peak 24-hour PM10 concentrations are forecasted to decline in Sacramento 

County. Figure 6.1 shows historical 3-year peak 24-hour PM10 concentrations from 

1988-2008 and the predicted peak during the 10-year maintenance period, 2012-2022. 

The peak 24-hour PM10 concentration is predicted to be 104 μg/m3

 at the start of the 

maintenance period in 2012 and 99 μg/m3

 at the end of the maintenance period in 2022. 

Therefore, 10-year maintenance of the 24-hour PM10 NAAQS (150 μg/m3) is 

demonstrated through 2022, due to declining NOX and motor vehicle exhaust 

emissions, despite increasing fugitive dust and wood smoke emissions. 
PM10 Implementation/Maintenance Plan and 

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Maintenance Demonstration 

Page 6-6 

Figure 6.1 

3-Year Peak* 24-Hour PM10 Concentration Trend and 

NAAQS 10-Year Maintenance Demonstration for Sacramento County 

99 104

0

20

40

60

80

100

120

140

160

180

200

1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 2022

Year

24-Hour PM10 Concentration (μg/m3

)

0

20

40

60

80

100

120

140

160

180

200

Sacramento 3-Year Peak Conc. NAAQS Maintenance Demonstration 24-Hour PM10 NAAQS Standard

*For example: 3-year maximum for 2008 is the peak concentration of 109 μg/m3 

Data Source: Ambient PM10 monitoring data from FRM high volume samplers with size selective inlet.

6.5 Future Monitoring Network 

EPA guidance states that once an area has been redesignated, the area should 

continue to operate an appropriate air quality monitoring network, in accordance with 40 

CFR Part 58, to verify the attainment status of the area (Calcagni, 1992). The 

maintenance plan should contain provisions for continued operation of air quality 

monitors that will provide such verification. 

As mentioned in Chapter 3 of this report, there are two types of PM10 monitors currently 

used throughout the monitoring network: 1) the Federal Reference Method (FRM) filter 

based high-volume sampler (hi-vols), 2) the Federal Equivalent Method (FEM) Tapered 

Element Oscillating Microbalance (TEOM), which measures PM10 on a continuous 24-

hour basis. The schedule for PM10 sample collection is one in six days for the filter 

based high-volume samplers. There are currently six PM10 monitoring sites within 

Sacramento County. 

The SMAQMD will assure the on-going quality of the measured data by performing the 

operational procedures for data collection, including routine calibrations, pre-run and 

post-run test procedures, and routine service checks. An annual review of the entire air 

quality monitoring network is required by federal regulations as a means to determine if 

the network is effectively meeting the objectives of the monitoring program. If relocation 

or a closure is recommended in the annual network review, reports are submitted to 

EPA and ARB to document compliance with siting criteria. The data collection 

procedures already in place, in conjunction with the annual review program, will ensure 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Maintenance Demonstration 

Page 6-7 

that the future PM10 ambient monitoring network in Sacramento County meets or 

exceeds the minimum monitoring requirements and that ambient PM10 concentrations 

are monitored appropriately to verify the attainment status of the area. 

6.6 Verification and Tracking the Maintenance Demonstration 

EPA guidance states that the maintenance plan submittal should indicate how the 

progress of the maintenance plan will be tracked. “This is necessary due to the fact that 

the emission projections made for the maintenance demonstration depend on 

assumptions of point and area source growth” (Calcagni, 1992). Options for tracking the 

progress of the maintenance demonstration would be to periodically (typically every 3 

years) review and update the emissions inventory, if needed, and reevaluate the 

assumptions and inputs used in the demonstration. In any event, the indicators for 

triggering contingency measures (specified in Chapter 7) should be monitored as well. 

The SMAQMD will review the assumptions and data for the PM10 maintenance 

demonstration in 2015 and 2018 to fulfill the verification and tracking requirements. The 

SMAQMD will also continue to operate an appropriate PM10 ambient monitoring network 

in Sacramento County to track maintenance of the PM10 standard and monitor the 

indicator for triggering the maintenance contingency plan. 

In addition, two years prior to the end of the maintenance planning period, Clean Air Act 

(CAA Section 175A) requirements specify that a subsequent maintenance plan is 

required. This second plan must provide for maintenance of the NAAQS for 10 more 

years after expiration of the first 10-year maintenance period. Therefore, the SMAQMD 

will prepare and submit another maintenance plan in 2020 to demonstrate maintenance 

of the PM10 standard through 2032. 

6.7 References 

Calcagni, John. Procedures for Processing Requests to Redesignate Areas to 

Attainment. Air Quality Management Division, EPA, September 4, 1992, p. 11-12. 

SJVAPCD. 2007 PM10 Maintenance Plan and Request for Redesignation, Appendix F. 

Modeling Analysis. September 20, 2007, p. 60-98. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Maintenance Contingency Plan 

Page 7-1 

7. MAINTENANCE CONTINGENCY PLAN 

7.1 Introduction to Contingency Plan 

A contingency plan provides for future actions and additional measures to implement if 

needed to mitigate any unexpected increases in emissions and ambient air quality 

concentrations to ensure specific targets and goals are achieved to maintain the 

applicable NAAQS. This chapter mentions the federal requirements for a PM10

maintenance contingency plan and discusses the proposed SMAQMD contingency plan 

to fulfill these requirements. 

7.2 Contingency Plan Requirements 

Section 175A (d) of the Clean Air Act requires a maintenance plan to: 

 Include contingency provisions, as necessary, to promptly correct any violation of 

the standard that occurs after redesignation of the area to attainment. 

 Provide a contingency provision to implement all control measures contained in the 

nonattainment SIP for the area before redesignation to attainment. 

EPA guidance further states that fully adopted contingency measures that will take 

effect without further action are not required in order for the maintenance plan to be 

approved (Calcagni, 1992). However, the contingency plan is considered to be an 

enforceable part of the SIP and should ensure that the contingency measures are 

adopted expediently once they are triggered. The plan should clearly identify the 

measures to be adopted, a schedule and procedure for adoption and implementation, 

and a specific time limit for action. It is also necessary for the contingency plan to 

identify specific indicators or triggers which will be used to determine when the 

contingency measures need to be implemented. EPA will review the maintenance 

contingency plan on a case-by-case basis. 

In addition, Section 175A (d) of the Clean Air Act specifies that the failure of any area, 

which has been redesignated as an attainment area, to maintain the national ambient 

air quality standard concerned shall not result in a requirement for a SIP revision unless 

EPA, in its discretion, requires such submittal. 

7.3 Maintenance Contingency Plan 

The contribution of sources to the PM10 problem can vary at different seasons of the 

year under a variety of different meteorological conditions. Therefore, the SMAQMD is 

proposing a contingency strategy to evaluate applicable PM10 events that trigger the 

contingency plan and take appropriate action to ensure continued maintenance of the 

PM10 NAAQS. It is recommended that the SMAQMD implement the contingency plan 

during the maintenance period if a PM10 monitor should violate the 24-hour PM10

NAAQS (150 μg/m3) not due to natural or exceptional events. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Maintenance Contingency Plan 

Page 7-2 

After verification of a monitoring violation of the PM10 NAAQS, which includes sufficient 

time for sample weighing and processing, the following major steps are envisioned for 

the contingency plan process: 

1. First, the SMAQMD will examine the event and determine if it needs to be classified 

as a natural or exceptional event in accordance with EPA requirements. If the data 

qualify for flagging, the SMAQMD would proceed with preparing and submitting the 

necessary documentation for a natural or exceptional event, as required by EPA’s 

“Treatment of Data Influenced by Exceptional Events” Rule (72 CFR 13560). The 

flagged data would not be considered to trigger the maintenance contingency plan. 

2. Second, if the event does not qualify as a natural or exceptional event, the 

SMAQMD would then analyze the event to determine its possible causes. Any 

applicable emission reductions from already adopted rules that have not yet been 

implemented would be evaluated to determine if these new emission reductions 

would be sufficient to prevent future PM10 exceedances. These already adopted 

controls could include CARB and District PM2.5 and NOX measures to address ozone 

and PM2.5 SIP requirements. In addition, the District would evaluate applicable 

reasonably available control measures (RACM) that could potentially provide the 

corrective action needed. This evaluation step will take no more than 18 months. 

3. Third, if the additional emission reductions from already adopted rules are 

insufficient, the SMAQMD would proceed with selecting specific RACM measures for 

adoption and implementation that would be applicable to addressing the seasonal 

PM10 problem. The contingency provision to implement all control measures 

contained in the nonattainment SIP for the area before redesignation to attainment 

does not apply since there were no additional SIP measures proposed beyond 

existing measures. This adoption and implementation step will take no more than 12 

months. 

Details of the potential rules would be developed at that time. The rule development and 

adoption process would be subject to individual and specific public review and a 

separate Board of Directors public hearing. 

7.4 Contingency Plan Conclusions 

The proposed contingency plan is expected to ensure prompt correction of any violation 

of the PM10 NAAQS that occurs after redesignation and provide continued maintenance 

of the standard. The plan identifies a specific indicator or trigger to determine when the 

contingency requirements are activated for evaluating, selecting, developing, and 

adopting the most appropriate contingency measures in an expedient timeframe. A 

suggested list of reasonably available control measures is in Appendix B, which may 

provide cost-effective, particulate matter emissions reduction benefits. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Maintenance Contingency Plan 

Page 7-3 

7.5 References 

Calcagni, John. Procedures for Processing Requests to Redesignate Areas to 

Attainment, Air Quality Management Division, EPA, September 4, 1992. 

USEPA, Treatment of Data Influenced by Exceptional Events, Federal Register, Volume 

72, March 22, 2007, p. 13560-13581. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Transportation Conformity Budgets 

Page 8-1 

8. TRANSPORTATION CONFORMITY BUDGETS

8.1 Introduction to Transportation Conformity 

Transportation conformity is the federal regulatory procedure for linking and 

coordinating the transportation and air quality planning processes. Under the 1990 

Clean Air Act Amendments, federal agencies may not approve or fund transportation 

plans and projects unless they are consistent with state air quality implementation plans 

(SIPs). Conformity with the SIP requires that transportation activities (1) not cause or 

contribute new air quality violations, (2) increase the frequency or severity of any 

existing violation, or (3) delay timely attainment of National Ambient Air Quality 

Standards (NAAQS). The quantification and comparison of on-road motor vehicles 

emissions is one of the elements for determining transportation conformity between air 

quality and transportation planning. 

This chapter provides a summary of principal transportation conformity requirements 

and proposed motor vehicles emissions budgets (MVEB) for PM10 and for NOX, which is 

a significant PM10 precursor forming ammonium nitrate particulates. 

8.2 Transportation Conformity Requirements 

The CAA Section 176 states that no federal department engage in, support in any way 

or provide financial assistance for or license or approve any activity that does not 

conform to the State Implementation Plan (SIP). To implement this requirement, EPA 

established the Transportation Conformity Rule (40 CFR §93). This Rule: 

 Establishes criteria and procedures for determining whether long range

metropolitan transportation plans (MTPs), short range metropolitan transportation

improvement programs (MTIPs), and projects conform to the SIP.

 Ensures that transportation plans and projects are consistent with the applicable

SIP, such that associated transportation emissions are less than or equal to motor

vehicle emissions budgets established for demonstrating reasonable further

progress, attainment or maintenance of health-based air quality standards.

 Ensures that transportation plans, programs, and other individual projects do not

cause new air quality violations, exacerbate existing ones, or delay attainment of air

quality standards.

8.3 Latest Planning Assumptions

Sacramento County had rapid growth in population, number of households, number of 

dwelling units, and jobs in the last two decades and these trends are expected to 

continue. Forecasting of these factors is important in establishing the MVEB. 

Sacramento Area Council of Governments (SACOG) adopted population, dwelling units 

and employment forecasts in September 2007. These are applied to vehicle miles 

traveled (VMT) forecasting. The current and forecasted VMT estimates are from 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Transportation Conformity Budgets 

Page 8-2 

SACOG-supplied activity data which are from the SACSIM regional travel demand 

model prepared for the August 2009 Metropolitan Transportation Improvement Program 

(MTIP) analysis (SACOG, 2010). The 2009 MTIP is based on transportation projects 

included in the SACOG Metropolitan Transportation Plan for 2035 (MTP2035). 

8.4 SACOG’s MTP2035 

Over the past several years, the Sacramento region has embarked on a process of 

defining and implementing a new, higher density, land use pattern which reduces 

congestion, encroachment on open space, average vehicle miles traveled per 

household and air pollutants. The program, called Blueprint, was initiated by SACOG 

with the goal of reducing traffic congestion in future metropolitan transportation plans. 

In December 2004, Blueprint smart growth principles and a 2050 growth scenario were 

approved by SACOG (SACOG, 2004) to achieve the following objectives: 

1. Provide a variety of transportation choices 

2. Offer housing choices 

3. Take advantage of compact development 

4. Use existing assets 

5. Increase mixed land use 

6. Encourage natural resource conservation 

7. Ensure distinctive, attractive communities with quality design 

The region then began the more detailed planning efforts for the long range MTP2035. 

SACOG works with local jurisdictions, California Department of Transportation 

(CalTrans), and transportation and planning agencies to define interim land use 

allocations and specific transportation project needs. Federal MTP guidelines require 

that the land use allocations represent what is most likely to be built. Therefore, the 

specific Blueprint smart growth policies affect land use allocations only to the extent that 

the local jurisdictions and SACOG are able to demonstrate that the policies will actually 

be implemented. The MTP2035 was adopted by the SACOG Board on March 20, 2008 

(SACOG, 2008). 

SACOG’s Transportation Model 

The transportation analysis for the 2009 MTIP and MTP2035 relied on the latest 

planning assumptions and SACOG’s new regional travel demand forecasting model, 

SACSIM (Bradley et al, 2007). The SACSIM model was used to estimate future traffic 

volumes and public transit ridership in the 6-county Sacramento region. SACSIM 

incorporates an “activity-based” travel model which simulates the population of 

households allocated to parcels and creates a one-day activity and trip travel schedule 

for each person in the population. 
PM10 Implementation/Maintenance Plan and 

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Transportation Conformity Budgets 

Page 8-3 

The activity and travel schedule are sensitive to transportation network accessibility and 

a variety of demographic and land use variables. SACSIM also incorporates a mode 

choice (i.e. bus, car, bike, walking, etc) model which determines how each travel 

destination is reached. 

The network traffic assignment models load the trips onto the network, resulting in 

vehicle miles traveled at four time intervals (AM peak, midday, PM peak, and 

evening/early morning) and speed within each time period. To develop the travel 

forecasting, information on the characteristics and constraints of the transportation 

system and residents’ travel survey data were collected. The SACSIM travel outputs 

were compared to actual base year data to be able to demonstrate adequate model 

performance results. 

SACOG used the SACSIM travel demand model to forecast average weekday travel 

patterns for several future years, based on given assumptions about expected future 

population and employment projections (SACOG, 2007), land use allocations, and 

transportation system improvements and changes contained in the MTP2035. The 

results of the travel model predicted that growth in vehicle trips and growth in vehicle 

miles traveled will be slightly lower than the population growth rate for the Sacramento 

region through 2035. 

8.5 Proposed Motor Vehicle Emission Budgets 

To reflect the updated motor vehicle emission forecasts, the PM10

Implementation/Maintenance Plan and Redesignation Request for Sacramento County 

include transportation conformity budgets for 2008, 2012 and 2022. These years are 

selected because 2008 is the emission inventory base year, the beginning of the 

maintenance period is 2012, and the end of the 10 year maintenance period is 2022. 

The proposed transportation budgets listed in Table 8.1, incorporate: 

1) The recent on-road motor vehicle emission inventory factors of EMFAC2007,15 

2) Updated travel activity data from SACOG’s August 2009 MTIP analysis, based 

on the SACSIM (Sacramento Activity-Based Travel Demand Simulation Model) 

transportation modeling system (SACOG, 2010), and 

3) Latest regional and state control strategies. 

The PM10 Motor Vehicle Emissions Budget for conformity purposes includes regional reentrained dust from travel on paved roads, vehicular exhaust, travel on unpaved roads, 

and road construction. Transportation Conformity Rule (40 CFR Part 93, §93.122(e)(2)) 

requires that PM10 from construction-related fugitive dust be included in the regional 

PM10 emissions analysis if it is identified as a contributor to the nonattainment problem 

in a PM10 implementation plan. 

 

15 CARB’s EMFAC2007 model (version 2.3) was released November 2006. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Transportation Conformity Budgets 

Page 8-4 

In addition to PM10, Transportation Conformity Rule (40 CFR Part 93, §93.102(b)(2)(iii)) 

identifies volatile organic compounds (VOC) and oxides of nitrogen (NOX) as PM10

precursor pollutants that must also have a motor vehicle emissions budget if deemed a 

significant contributor to the PM10 nonattainment problem. The CMB modeling analysis 

in Chapter 6 indicates that the secondary formation of ammonium nitrate from NOX

emissions contributes a significant amount to the wintertime ambient PM10

concentration. 

An additional 1.5 tons per day of PM10 were added to the 2022 PM10 budgets in order to 

account for potential emission increases in Paved Road Dust (1.0 ton per day) and 

Road Construction Dust (0.5 ton per day) beyond 2022. This additional increase may be 

needed for SACOG to make a transportation conformity determination for a horizon 

year of 2035 or later for transportation planning purposes when using the latest year of 

motor vehicle emissions budgets (2022) in this maintenance plan. Transportation 

Conformity Rule (40 CFR Part 93, §93.124(a) allows an implementation plan to explicitly 

increase the motor vehicle emissions budgets for available use by the Metropolitan 

Planning Organization (MPO) and the Department of Transportation (DOT) for 

conformity purposes as long as emissions will be lower than needed to provide for 

continued maintenance. 

The additional increase in 1.0 ton per day of PM10 to Paved Road Dust and 0.5 ton per 

day of PM10 to Road Construction Dust in the 2022 transportation budgets are 

accounted for in the maintenance demonstration emission forecasts for Fugitive Dust 

PM10 in Chapter 6. The additional increase in the 2008, 2012, and 2022 NOX and PM10

transportation budgets due to rounding up to the nearest ton are also accounted for in 

the maintenance demonstration emission forecasts for Total NOX and Fugitive Dust 

PM10. 

The proposed motor vehicle budgets for NOX and PM10 average winter day emissions in 

Table 8.1 are for the Sacramento County which is the nonattainment area for federal 

PM10 standards. 

Table 8.1: Motor Vehicle Emissions Budgets for Maintenance of PM10 NAAQS 

Sacramento County 2008 2012 2022 

 NOX PM10 NOX PM10 NOX PM10

Direct Exhaust 

(includes tire and brake wear for PM10) 49.6 2.2 37.6 2.1 18.1 2.1 

Paved Road Dust --- 6.1 --- 6.2 --- 6.4 + 1.0

Unpaved Road Dust --- 3.6 --- 3.6 --- 3.6 

Road Construction Dust --- 2.7 --- 2.8 --- 2.8 + 0.5

Total (rounded up to nearest ton) 50 15 38 15 19 17 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Transportation Conformity Budgets 

Page 8-5 

8.6 Impact of New Emission Budgets 

Currently, Sacramento County has no established PM10 budgets. The Metropolitan 

Planning Organization, SACOG, uses “build vs no build” test to determine transportation 

conformity for the region’s transportation plans and programs for PM10. If the proposed 

MVEBs are determined to be adequate by EPA, future transportation plans will need to 

conform to these motor vehicle emissions budgets in any future transportation plan 

amendment and updates. SACOG must ensure that the aggregate wintertime 

transportation emissions in Sacramento County (including, but not limited to, vehicle 

emissions, dust from paved and unpaved roads and road construction), rounded up to 

the nearest integer, do not exceed these levels when approving new metropolitan 

transportation plans and transportation improvement programs, even if the mix of 

projects changes or growth increases. Following EPA action, these new NOX and PM10

MVEBs will remain in effect until other budgets are found adequate or approved by 

EPA. 

8.7 References 

Bradley, M.A., Bowman J.L. and Griesenbeck B. Development and application of the 

SACSIM activity-based model system. Berkeley, CA [2007.] 

SACOG. Examples from the Sacramento Region of the seven principles of smart 

growth: Better Ways to Grow. Sacramento, CA: Sacramento Area Council of 

Governments, Sacramento, CA [2004.] Web. January 7, 2010. 

<http://www.sacog.org/regionalfunding/betterways.pdf> 

SACOG. SACOG Board of Directors approved 2013 and 2018 housing and employment 

allocations based on July 2007 California Department of Finance projections. 

Sacramento, CA [2007.] 

SACOG. Sacramento Region Metropolitan Transportation Plan for 2035, Sacramento 

Area Council of Governments. Sacramento, CA [2008.] 

SACOG. Sacramento County travel data for PM10 plan, Griesenbeck e-mail to 

Anderson, SMAQMD, July 12, 2010, Sacramento Area Council of Governments 

[2010]. 

SMAQMD. Sacramento Regional 8-Hour Ozone Attainment And Reasonable Further 

Progress Plan (with errata sheets incorporated). Sacramento, CA: Sacramento 

Metropolitan Air Quality Management District, Sacramento, CA [2009.] 

USEPA. Transportation Conformity Rule Amendment To Implement Provisions 

Contained in the 2005 Safe, Accountable, Flexible, Efficient Transportation 

Equity Act: A Legacy for Users (SAFETEA-LU), Federal Register, Volume 73, 

January 24, 2008, p. 4420. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Redesignation Request 

Page 9-1 

9. REDESIGNATION REQUEST 

9.1 Introduction to Redesignation and Redesignation Requirements 

The Sacramento Metropolitan Air Quality Management District is requesting that the 

Environmental Protection Agency (EPA) redesignate Sacramento County to attainment 

status for the PM10 National Ambient Air Quality Standards (NAAQS). The Air District 

has met the criteria for the EPA Administrator to promulgate redesignation as outlined in 

the Federal Clean Air Act (CAA) Section 107(d)(3)(E). 

The EPA Administrator may not promulgate a redesignation of a nonattainment area (or 

portion thereof) to attainment unless — 

 the Administrator determines that the area has attained the national ambient air 

quality standard; 

 the Administrator has fully approved the applicable implementation plan for the 

area under Section 110 (k); 

 the Administrator determines that the improvement in air quality is due to 

permanent and enforceable reductions in emissions resulting from 

implementation of the applicable implementation plan and applicable Federal air 

pollutant control regulations and other permanent and enforceable reductions; 

 the Administrator has fully approved a maintenance plan for the area as meeting 

the requirements of Section 175A; and 

 the State containing such area has met all requirements applicable to the area 

under Section 110 and Part D. 

The following Table 9.1 includes the compliance statements for each of the 

redesignation criteria. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Redesignation Request 

Page 9-2 

Table 9.1 

Compliance with CAA Section 107(d)(3)(E) Criteria 

for Redesignation to Attainment for PM10 NAAQS 

Criterion Compliance 

Attainment of the PM10

NAAQS 

USEPA found the Sacramento County to be in attainment 

of the PM10 NAAQS (67 FR 7082). 24-hour PM10 attainment 

demonstrated for last 3 years (2007-2009) in Table 9.2. 

State Implementation Plan 

(SIP) Approval under CAA 

Section 110(k) 

PM10 Implementation Plan elements are submitted in this 

Plan and are discussed in Sections 2.5 to 2.7. Chapter 3 

describes the PM10 air quality monitoring network. Chapter 

4 documents the emissions inventory. Chapter 5 discusses 

the control measures responsible for attainment and the 

SMAQMD new source review stationary source permit 

program. 

Permanent and Enforceable 

Improvement in Air Quality 

Section 9.2.3 in this Plan demonstrates that Sacramento 

County’s improvement in PM10 air quality was due to 

permanent and enforceable emissions reductions achieved 

through Air District and CARB rules and regulations that will 

remain in effect after redesignation to attainment. Long term 

trends show emissions decreased and air quality improved 

in spite of growth in population and vehicle miles traveled. 

Fully Approved 

Maintenance Plan 

In accordance with EPA Guidance (Calcagni, 1992), the 

PM10 Maintenance Plan is submitted in this Plan with the 

request for redesignation. Chapter 4 includes the emission 

inventories, documenting a base year and forecast 

inventories for the maintenance period. Chapter 6 includes 

the maintenance demonstration analysis and a commitment 

to an appropriate future monitoring network, and verification 

and tracking of the maintenance demonstration. Chapter 7 

describes the maintenance contingency plan. 

CAA Section 110 and Part 

D requirements 

Contingent to the EPA approval of this PM10

Implementation/Maintenance Plan and the Motor Vehicle 

Emissions Budgets, this would satisfy the CAA Section 110 

and Part D requirements. 

9.2 Evaluation of Redesignation 

9.2.1 Attainment of PM10 NAAQS 

USEPA published a Proposed Rule on July 25, 2001 (66 FR 38603), and a Final Rule of 

Attainment Finding on February 15, 2002 (67 FR 7082) determining that the 

Sacramento County had attained the PM10 NAAQS. The Final Rule became effective on 

March 18, 2002. The Rule contained the Sacramento PM10 monitoring data which 

showed no measured exceedances of the 24-hour PM10 NAAQS between 1998 and 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Redesignation Request 

Page 9-3 

2000. The February 15, 2002 finding determined that the Sacramento County attained 

the 24-hour and annual PM10 standards by the attainment date of December 31, 2000. 

Data collected since the 2000 attainment determination continues to show that 

Sacramento County has not had any violations and meets the federal PM10 standard. 

Table 9.2 contains a summary of FRM PM10 air quality data for the six Sacramento 

County monitoring sites for the last 3 years, 2007-2009. The highest 24-hour PM10

concentration over this 3-year period was 97 μg/m3, recorded at the North Highlands 

monitoring site. The 2009 design value of 97 μg/m3 is below the 24-hour PM10 NAAQS 

of 150 μg/m3. Therefore, the number of expected exceedances per year from all 

monitoring sites in the area is less than 1.0, which demonstrates continued attainment 

of the standard. 

Table 9.2 

Summary of PM10 Air Quality Data – Sacramento County 2007-2009 

Sacramento County Monitoring Site 

Highest 24-Hour Concentration (μg/m3

) 

2007 2008 2009 

North Highlands – Blackfoot Way 56 97 33 

Sacramento – Branch Center Road 2 56 89 76 

Sacramento – Del Paso Manor 70 71 45 

Sacramento – Goldenland Court 56 48 

Sacramento – Health Dept Stockton Blvd 56 88 45 

Sacramento – T Street 53 73 47 

9.2.2 Fully Approved State Implementation Plan 

The Air District is submitting the required PM10 Implementation Plan elements to meet 

the requirement. Contingent to the approval of this Plan, the Sacramento nonattainment 

area would satisfy the requirement of having a fully approved applicable implementation 

plan. There have been no previous disapprovals, or partial, conditional, or limited 

approvals of required elements of a PM10 Implementation Plan. Approval of the PM10

State Implementation Plan would allow EPA to proceed with the redesignation of 

Sacramento County as attainment for the PM10 NAAQS. 

PM10 Implementation Plan elements are discussed in Sections 2.5 to 2.7. Chapter 3 

describes the PM10 air quality monitoring network. Chapter 4 documents the emissions 

inventory. Chapter 5 discusses the control measures responsible for attainment and the 

SMAQMD new source review stationary source permit program. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Redesignation Request 

Page 9-4 

9.2.3 Permanent and Enforceable Improvement in Air Quality 

EPA redesignation guidance states that “the State must be able to reasonably attribute 

the improvement in air quality to emission reductions which are permanent and 

enforceable” (Calcagni, 1992). It also further notes that temporary emission reductions 

or “unusually favorable meteorology” would not qualify as an air quality improvement 

due to permanent and enforceable emission reductions. 

Figure 9.1 shows the long term air quality trend of maximum 24-hour PM10 from 1986 to 

2009. The air monitoring data shows no violation since 1991 and the annual maximum 

concentrations are maintained below the 24-Hour PM10 NAAQS16. Additionally, the data 

do not show any upward air quality trend for the annual maximum 24-hour PM10

concentrations at an air monitoring station. 

Figure 9.1 

Annual Maximum 24-hour PM10 Concentration (μg/m3

) 

Sacramento County for 1986-2009 

0

20

40

60

80

100

120

140

160

180

200

1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2008

Year

Maximum 24-Hour PM10 Concentration (μg/m3

)

Sacramento-Peak Monitoring Site 24-Hour PM10 NAAQS Standard Linear (Sacramento-Peak Monitoring Site)

Data source: Ambient PM10 monitoring data from high volume samplers with size selective inlet 

(SMAQMD, 1996 and CARB, 2009)

Since the Sacramento County has not had a 24-hour PM10 violation for the past 19 

years, this demonstrates that the attainment is not a result of temporary emission 

reductions or from “unusually favorable meteorology”. The Sacramento County 

 

16 When comparing a 24-hour average PM10 concentration to the federal standard of 150 μg/m3

, the 

concentration value is rounded to the nearest 10 μg/m3

. Therefore, the minimum concentration exceeding 

the 24-hour standard is 155 μg/m3

, which rounds to 160 μg/m3. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Redesignation Request 

Page 9-5 

experienced a variety of meteorological conditions over the past 19 years (1991-2009.) 

Although the Sacramento County experienced growth in both population and vehicle 

miles traveled (VMT), these conditions have not lead to a violation of the 24-hour PM10

NAAQS due to the implementation of emission reduction measures which resulted in 

declining emissions. Figure 9.2 shows the population and VMT historical growth and 

projection for Sacramento County. Figure 9.3 shows the historical and projected 

emission inventory for PM10 and its NOX precursor. 

Figure 9.2 

Population and VMT for Sacramento County 

1990-2022 (historical data and projection) 

0.00

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

1990 1995 2000 2005 2010 2015 2020

YEAR

Population (million) 

0

5000

10000

15000

20000

25000

30000

35000

40000

45000

50000

VMT (Thousands of miles per day)

Population VMT
PM10 Implementation/Maintenance Plan and 

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Redesignation Request 

Page 9-6 

Figure 9.3 

PM10 and NOX Precursor Emissions for Sacramento County 

1990-2022 (historical data and projection) 

0

20

40

60

80

100

120

140

160

180

1990 2000 2008 2012 2022

Year

Tons per Day

NOx PM10

9.2.4 Fully Approved Maintenance Plan 

In accordance with EPA guidance (Calcagni, 1992) the Air District is submitting this 

PM10 Maintenance Plan and request for redesignation for Sacramento County. Approval 

of this document would allow EPA to proceed with redesignation of the Sacramento 

County as attainment for the PM10 NAAQS. Chapter 4 includes the emission 

inventories, documenting a base year and forecast inventories for the maintenance 

period. Chapter 6 includes the maintenance demonstration analysis, showing continued 

maintenance of the PM10 NAAQS from 2012 to 2022. Chapter 6 also contains a 

commitment to a future monitoring network and verification and tracking of the 

maintenance demonstration. Chapter 7 describes the maintenance contingency plan to 

ensure prompt correction of any violation of the NAAQS. 

9.2.5 CAA Section 110 and Part D Requirements 

Contingent to the approval of this Implementation/Maintenance Plan and the Motor 

Vehicle Emissions Budgets discussed in Chapter 8, the Sacramento PM10

nonattainment area would meet the requirements of Section 110 and applicable 

portions of Part D of the Federal Clean Air Act. This would allow EPA to proceed with 

redesignation of the Sacramento County as attainment for the PM10 NAAQS. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Redesignation Request 

Page 9-7 

9.3 References 

Calcagni, John. Memorandum, Procedures for Processing Requests to Redesignate 

Areas to Attainment. United States Environmental Protection Agency, Office of 

Air Quality Planning and Standards, Research Triangle Park, NC [1992.]

CARB. CEPAM: 8-Hour Ozone SIP Baseline Emission Projections – Version 1.06 MAIN 

Planning Inventory Tool. CA: California Air Resources Board, 28 February 2007. 

Web. 31 December 2009. 

<http://www.arb.ca.gov/app/emsinv/o3sip/fcemssumcat_o3v106.php. 

CARB. CEPAM: 2009 Almanac – Population and Vehicle Trends Tool. CA: California 

Air Resources Board, Sacramento, CA [2009.] 

CARB. iADAM Air Quality Data Statistics. CA: California Air Resources Board, 

Sacramento, CA, 15 April 2009. Web. 31 December 2009. 

< http://www.arb.ca.gov/adam/welcome.html>. 

SJVAPCD. 2007 PM10 Maintenance Plan and Request for Redesignation. Fresno, CA: 

San Joaquin Valley Air Pollution Control District, Fresno, CA [2007.] 

SMAQMD. Revised Draft 1995 Attainment and Maintenance Plan For The Federal PM10

Standard. Sacramento, CA: Sacramento Metropolitan Air Quality Management 

District, Sacramento, CA [1996.] 

USEPA Designation of Areas for Air Quality Planning Purposes, Federal Register, 

Volume 56, November 6, 1991, p. 56694. 

USEPA. Proposed Rule: Clean Air Act Attainment Finding; Bullhead City and Payson 

Nonattainment Areas, AZ; Sacramento and San Bernardino Nonattainment 

Areas, CA; Particulate Matter of 10 Microns or Less (PM-10). Federal Register, 

Volume 66, July 25, 2001, p. 38603. 

USEPA. Final Rule: Clean Air Act Attainment Finding; Bullhead City and Payson 

Nonattainment Areas, AZ; Sacramento and San Bernardino Nonattainment 

Areas, CA; Particulate Matter of 10 Microns or Less (PM-10). Federal Register, 

Volume 67, February 14, 2002, p. 7082. 

USEPA. Final Rule: Air Quality Designations for the 2006 24-Hour Fine Particle (PM2.5) 

National Ambient Air Quality Standards. Federal Register, Volume 74, November 

13, 2009, p.58688. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Summary and Conclusions 

Page 10-1 

10. SUMMARY AND CONCLUSIONS 

10.1 PM10 Nonattainment Designation 

Upon enactment of the 1990 Clean Air Act Amendments, Sacramento County was 

designated as unclassifiable for PM10. However, during 1989 and 1990, two different 

SMAQMD PM10 monitors (Del Paso Manor and Stockton Boulevard sites) violated the 

24-hour PM10 standard. Effective January 20, 1994, EPA took final action to redesignate 

Sacramento County as a “moderate” nonattainment area for the PM10 NAAQS with an 

attainment deadline of December 31, 2000. 

10.2 PM10 Air Quality Data 

PM10 air quality data includes solid and liquid particles with a diameter of 10 

micrometers or less. EPA's health-based national ambient air quality standard for 24-

hour PM10 is 150 μg/m3 (measured as a daily concentration). There are currently six 

PM10 monitoring sites within Sacramento County. The Chemical Mass Balance (CMB) 

model was used to identify the source contributions for ambient air quality samples. 

CMB results show that the main source types contributing to PM10 air quality in 

Sacramento were secondary ammonium nitrate particles, motor vehicles exhaust, wood 

smoke, and fugitive dust. EPA determined that the Sacramento PM10 nonattainment 

area attained the PM10 NAAQS as of December 31, 2000 since no exceedances of the 

24-hour PM10 NAAQS were measured between 1998 and 2000. There have been no 

violations of the PM10 NAAQS through 2009. 

10.3 Emissions Inventory 

The emissions inventory is an account of pollutant emissions that estimates the amount 

of air pollutants emitted from many sources. This maintenance plan includes an 

emissions inventory for total primary PM10 and NOX as a PM10 precursor. 2008 is the 

base year, the year from which the inventory is projected forward and backward. An 

examination of the emissions inventory indicates that the three largest categories of 

primary PM10 are the area-wide sources for paved road dust, residential fuel 

combustion, and construction & demolition, while mobile source categories contribute 

over 85% of the NOX emissions inventory. Between 2008 and 2022, total PM10

emissions are expected to increase 2-3% and NOX emissions are expected to steadily 

decrease by 48%, despite increasing vehicle miles traveled and population in 

Sacramento County. 

10.4 Control Measures 

The SMAQMD has adopted and implemented a number of PM control measures to 

reduce emissions from fugitive dust, wood burning devices, and agricultural burning. In 

addition, the SMAQMD has applied RACM/RACT rules to existing NOX sources, which 

will directly reduce the secondary formation of atmospheric ammonium nitrates, a 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Summary and Conclusions 

Page 10-2 

significant component of PM10 concentrations in the Sacramento area. Several emission 

reduction programs have also been implemented by the California Air Resources Board 

(CARB) to reduce directly emitted particulates and secondary PM precursor pollutants 

(NOX and SOX) from mobile sources. These measures primarily address cleaner fuel 

specifications for diesel and reformulated gasoline, and mobile source engine emission 

standards that CARB has implemented statewide. No new control measure 

commitments are included in this plan since the existing control strategy is predicted to 

maintain the PM10 NAAQS throughout the future 10-year maintenance period. 

10.5 Maintenance Demonstration 

Overall peak 24-hour PM10 concentrations are forecasted to decline in Sacramento 

County. The peak 24-hour PM10 concentration is predicted to be 104 μg/m3 at the start 

of the maintenance period in 2012 and 99 μg/m3 at the end of the maintenance period in 

2022. Therefore, 10-year maintenance of the 24-hour PM10 NAAQS (150 μg/m3) is 

demonstrated through 2022, due to declining NOX and motor vehicle exhaust 

emissions, despite increasing fugitive dust and wood smoke emissions. The SMAQMD 

will continue to operate an appropriate air quality monitoring network and review the 

assumptions and data for the PM10 maintenance demonstration to fulfill the verification 

and tracking requirements 

10.6 Contingency Plan 

The proposed contingency plan is expected to ensure prompt correction of any violation 

of the PM10 NAAQS that occurs after redesignation and continued maintenance of the 

standard. The plan identifies a specific indicator or trigger to determine when the 

contingency requirements are activated for selecting, developing, and adopting the most 

appropriate contingency measures in an expedient timeframe. Any applicable emission 

reductions from already adopted rules that have not yet been implemented would be 

evaluated to determine if these new emission reductions would be sufficient to prevent 

future PM10 exceedances. These already adopted controls could include CARB and 

District PM2.5 and NOX measures to address ozone and PM2.5 SIP requirements. In 

addition, the District would evaluate applicable reasonably available control measures 

(RACM), which may provide cost-effective particulate matter emissions reduction 

benefits that could potentially provide the corrective action needed. 

10.7 Transportation Conformity Budgets 

Under the 1990 Clean Air Act Amendments, federal agencies may not approve or fund 

transportation plans and projects unless they are consistent with state air quality 

implementation plans (SIPs). The quantification and comparison of on-road motor 

vehicle emissions is the method for determining transportation conformity between air 

quality and transportation planning. Currently, Sacramento County has no established 

PM10 motor vehicle emissions budgets (MVEBs). The Metropolitan Planning 

Organization, SACOG, uses “build vs no build” test to determine transportation 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Summary and Conclusions 

Page 10-3 

conformity for the region’s transportation plans and programs for PM10. To reflect 

updated motor vehicle emission forecasts, this maintenance plan for Sacramento 

County includes transportation conformity budgets for 2008, 2012 and 2022 for PM10

(including motor vehicle exhaust and road-related dust) and oxides of nitrogen (NOX), a 

significant PM10 precursor. If the proposed MVEBs are determined to be adequate or 

approved by EPA, SACOG must ensure that the aggregate transportation emissions do 

not exceed these motor vehicle emissions budgets in any future transportation plan 

amendment and updates. 

10.8 Redesignation Request 

The Sacramento Metropolitan Air Quality Management District is requesting that the 

Environmental Protection Agency (EPA) redesignate Sacramento County to attainment 

status for the PM10 national ambient air quality standards (NAAQS). The SMAQMD has 

met the following criteria for the EPA Administrator to promulgate redesignation as 

outlined in the Federal Clean Air Act (CAA) Section 107(d)(3)(E): 

1. Attainment of the PM10 NAAQS: effective March 18, 2002, continuing through 2009.

2. Fully approved PM10 SIP for the area: submittal contained in this plan.

3. Improvement in air quality is due to permanent and enforceable reductions: control

measures have reduced overall emissions despite increasing population and VMT,

and not due to temporary emission reductions or unusually favorable meteorology.

4. Fully approved PM10 maintenance plan for the area: submittal contained in this plan.

5. Met CAA Section 110 and Part D requirements: contingent on the approval of this

implementation and maintenance plan, and motor vehicle emissions budgets.

10.9 Overall Conclusions 

Collective local and state air quality regulations were successful in attaining the PM10

national ambient air quality standard (NAAQS) in Sacramento County by the 2000 

deadline. Continued attainment of the PM10 standard is demonstrated throughout the 

10-year maintenance period, 2012-2022, from existing control strategies. In addition, it 

is anticipated that future PM10 and NOX emission reductions will occur due to the 

adoption and implementation of new control measures needed for the attainment 

demonstration SIP efforts for achieving the PM2.5 and 8-hour ozone NAAQS in the 

region. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Appendices 

Title Page 

PM10 IMPLEMENTATION/MAINTENANCE PLAN AND 

REDESIGNATION REQUEST FOR SACRAMENTO COUNTY 

APPENDICES 

A. EMISSIONS INVENTORY 

B. CONTROL MEASURES 

C. TRANSPORTATION CONFORMITY BUDGETS 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Appendix A: Emissions Inventory 

Page A-1

Appendix A: Emissions Inventory 

The following tables show the anthropogenic emissions inventory of PM10 and NOX by 

source categories for Sacramento County. The emissions inventory is shown for 

average winter day in units of tons per day. Inventories were obtained from the 

California Air Resources Board (CARB) on September 3, 2010 for the years 2008, 

2012, and 2022.17 These inventories included recent CARB updates to the Residential 

Fuel Combustion and Paved Road Dust categories. 

An average winter emission inventory of PM10 and NOX is also shown for the years 

1990, 1995, and 2000. These inventories are used in the emissions trend analysis and 

the CMB analysis. The data source is CARB CEFS Version 1.06 Sacramento County 

(Rf#980), except Residential Fuel Combustion and Paved Road Dust were adjusted by 

SMAQMD staff to reflect the recent changes in CARB methodology. 

17 CARB (Ruiz) e-mail transmitting emissions inventory data for the Sacramento PM10 Maintenance Plan 

to SMAQMD (Tollstrup) on September 3, 2010. 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Appendix A: Emissions Inventory 

Page A-2

Sacramento PM10 Maintenance Plan - 2008 Emissions Data (Tons/Day)

(Sacramento County Only)

WINTER DAY

FYEAR

EIC 

SUM EICSUMN NOX PM10

2008 10 ELECTRIC UTILITIES 0.69 0.25

2008 20 COGENERATION 0.00 0.00

2008 30 OIL AND GAS PRODUCTION (COMBUSTION) 0.06 0.01

2008 50 MANUFACTURING AND INDUSTRIAL 0.99 0.04

2008 52 FOOD AND AGRICULTURAL PROCESSING 0.25 0.01

2008 60 SERVICE AND COMMERCIAL 1.52 0.16

2008 99 OTHER (FUEL COMBUSTION) 0.42 0.02

2008 110 SEWAGE TREATMENT 0.00 0.00

2008 120 LANDFILLS 0.02 0.01

2008 130 INCINERATORS 0.01 0.00

2008 199 OTHER (WASTE DISPOSAL) 0.00 0.00

2008 210 LAUNDERING 0.00 0.00

2008 220 DEGREASING 0.00 0.00

2008 230 COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

2008 240 PRINTING 0.00 0.00

2008 250 ADHESIVES AND SEALANTS 0.00 0.00

2008 299 OTHER (CLEANING AND SURFACE COATINGS) 0.00 0.00

2008 310 OIL AND GAS PRODUCTION 0.00 0.00

2008 330 PETROLEUM MARKETING 0.00 0.00

2008 410 CHEMICAL 0.03 0.03

2008 420 FOOD AND AGRICULTURE 0.00 0.10

2008 430 MINERAL PROCESSES 0.07 0.53

2008 440 METAL PROCESSES 0.01 0.01

2008 450 WOOD AND PAPER 0.00 0.18

2008 470 ELECTRONICS 0.00 0.00

2008 499 OTHER (INDUSTRIAL PROCESSES) 0.01 0.01

2008 510 CONSUMER PRODUCTS 0.00 0.00

2008 520 ARCHITECTURAL COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

2008 530 PESTICIDES/FERTILIZERS 0.00 0.00

2008 540 ASPHALT PAVING / ROOFING 0.00 0.01

2008 610 RESIDENTIAL FUEL COMBUSTION 4.42 9.91

2008 620 FARMING OPERATIONS 0.00 2.40

2008 630 CONSTRUCTION AND DEMOLITION 0.00 7.01

2008 640 PAVED ROAD DUST 0.00 6.12

2008 645 UNPAVED ROAD DUST 0.00 3.58

2008 650 FUGITIVE WINDBLOWN DUST 0.00 0.12

2008 660 FIRES 0.01 0.06

2008 670 WASTE BURNING AND DISPOSAL 0.06 0.20

2008 690 COOKING 0.00 0.82

2008 ALL ON-ROAD MOBILE 49.56 2.20

2008 810 AIRCRAFT 1.95 0.08

2008 820 TRAINS 3.37 0.09

2008 840 RECREATIONAL BOATS 0.52 0.06

2008 850 OFF-ROAD RECREATIONAL VEHICLES 0.01 0.00

2008 860 OFF-ROAD EQUIPMENT 16.00 1.04

2008 870 FARM EQUIPMENT 1.75 0.10

2008 890 FUEL STORAGE AND HANDLING 0.00 0.00

2008 TOTALS: 81.72 35.15

CMB PM10 Source Categories (EIC SUM)

Adjusted 

MVEB

Adjusted 

Total

Motor Vehicles PM10 (On-Road Mobile, 810-870) 3.57

Wood Smoke PM10 (610, 660, 670) 10.17

Fugitive Dust PM10 (430, 620-650) 19.77 0.4 20.17

Total NOx 81.72 0.4 82.12

Total PM10 35.15

Note that the increase in the motor vehicle emission budgets due to rounding up to the nearest integer is added to the

Fugitive Dust PM10 and Total NOx emission forecasts.

Fugitive Dust PM10: 14.6 rounds up to 15 = 0.4 increase

Total NOx: 49.6 rounds up to 50 = 0.4 increase
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Appendix A: Emissions Inventory 

Page A-3

Sacramento PM10 Maintenance Plan - 2012 Emissions Data (Tons/Day)

(Sacramento County Only)

WINTER DAY

FYEAR

EIC 

SUM EICSUMN NOX PM10

2012 10 ELECTRIC UTILITIES 0.83 0.30

2012 20 COGENERATION 0.00 0.00

2012 30 OIL AND GAS PRODUCTION (COMBUSTION) 0.06 0.01

2012 50 MANUFACTURING AND INDUSTRIAL 1.05 0.04

2012 52 FOOD AND AGRICULTURAL PROCESSING 0.18 0.01

2012 60 SERVICE AND COMMERCIAL 1.50 0.16

2012 99 OTHER (FUEL COMBUSTION) 0.38 0.02

2012 110 SEWAGE TREATMENT 0.00 0.00

2012 120 LANDFILLS 0.02 0.01

2012 130 INCINERATORS 0.01 0.00

2012 199 OTHER (WASTE DISPOSAL) 0.00 0.00

2012 210 LAUNDERING 0.00 0.00

2012 220 DEGREASING 0.00 0.00

2012 230 COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

2012 240 PRINTING 0.00 0.00

2012 250 ADHESIVES AND SEALANTS 0.00 0.00

2012 299 OTHER (CLEANING AND SURFACE COATINGS) 0.00 0.00

2012 310 OIL AND GAS PRODUCTION 0.00 0.00

2012 330 PETROLEUM MARKETING 0.00 0.00

2012 410 CHEMICAL 0.03 0.03

2012 420 FOOD AND AGRICULTURE 0.00 0.10

2012 430 MINERAL PROCESSES 0.07 0.57

2012 440 METAL PROCESSES 0.01 0.01

2012 450 WOOD AND PAPER 0.00 0.19

2012 470 ELECTRONICS 0.00 0.00

2012 499 OTHER (INDUSTRIAL PROCESSES) 0.01 0.02

2012 510 CONSUMER PRODUCTS 0.00 0.00

2012 520 ARCHITECTURAL COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

2012 530 PESTICIDES/FERTILIZERS 0.00 0.00

2012 540 ASPHALT PAVING / ROOFING 0.00 0.01

2012 610 RESIDENTIAL FUEL COMBUSTION 4.32 9.21

2012 620 FARMING OPERATIONS 0.00 2.32

2012 630 CONSTRUCTION AND DEMOLITION 0.00 7.22

2012 640 PAVED ROAD DUST 0.00 6.17

2012 645 UNPAVED ROAD DUST 0.00 3.58

2012 650 FUGITIVE WINDBLOWN DUST 0.00 0.12

2012 660 FIRES 0.01 0.06

2012 670 WASTE BURNING AND DISPOSAL 0.06 0.20

2012 690 COOKING 0.00 0.87

2012 ALL ON-ROAD MOBILE 37.61 2.13

2012 810 AIRCRAFT 2.25 0.09

2012 820 TRAINS 3.31 0.09

2012 840 RECREATIONAL BOATS 0.51 0.07

2012 850 OFF-ROAD RECREATIONAL VEHICLES 0.01 0.00

2012 860 OFF-ROAD EQUIPMENT 13.61 0.86

2012 870 FARM EQUIPMENT 1.44 0.08

2012 890 FUEL STORAGE AND HANDLING 0.00 0.00

2012 TOTALS: 67.28 34.54

CMB PM10 Source Categories (EIC SUM)

Adjusted 

MVEB

Adjusted 

Total

Motor Vehicles PM10 (On-Road Mobile, 810-870) 3.32

Wood Smoke PM10 (610, 660, 670) 9.47

Fugitive Dust PM10 (430, 620-650) 19.97 0.4 20.37

Total NOx 67.28 0.4 67.68

Total PM10 34.54

Note that the increase in the motor vehicle emission budgets due to rounding up to the nearest integer is added to the

Fugitive Dust PM10 and Total NOx emission forecasts.

Fugitive Dust PM10: 14.6 rounds up to 15 = 0.4 increase

Total NOx: 37.6 rounds up to 38 = 0.4 increase
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Appendix A: Emissions Inventory 

Page A-4

Sacramento PM10 Maintenance Plan - 2022 Emissions Data (Tons/Day)

(Sacramento County Only)

WINTER DAY

FYEAR

EIC 

SUM EICSUMN NOX PM10

2022 10 ELECTRIC UTILITIES 1.00 0.37

2022 20 COGENERATION 0.00 0.00

2022 30 OIL AND GAS PRODUCTION (COMBUSTION) 0.05 0.01

2022 50 MANUFACTURING AND INDUSTRIAL 1.22 0.05

2022 52 FOOD AND AGRICULTURAL PROCESSING 0.09 0.01

2022 60 SERVICE AND COMMERCIAL 1.52 0.16

2022 99 OTHER (FUEL COMBUSTION) 0.26 0.01

2022 110 SEWAGE TREATMENT 0.00 0.00

2022 120 LANDFILLS 0.02 0.01

2022 130 INCINERATORS 0.02 0.00

2022 199 OTHER (WASTE DISPOSAL) 0.00 0.00

2022 210 LAUNDERING 0.00 0.00

2022 220 DEGREASING 0.00 0.00

2022 230 COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

2022 240 PRINTING 0.00 0.00

2022 250 ADHESIVES AND SEALANTS 0.00 0.00

2022 299 OTHER (CLEANING AND SURFACE COATINGS) 0.00 0.00

2022 310 OIL AND GAS PRODUCTION 0.00 0.00

2022 330 PETROLEUM MARKETING 0.00 0.00

2022 410 CHEMICAL 0.03 0.03

2022 420 FOOD AND AGRICULTURE 0.00 0.11

2022 430 MINERAL PROCESSES 0.08 0.65

2022 440 METAL PROCESSES 0.01 0.01

2022 450 WOOD AND PAPER 0.00 0.22

2022 470 ELECTRONICS 0.00 0.01

2022 499 OTHER (INDUSTRIAL PROCESSES) 0.01 0.03

2022 510 CONSUMER PRODUCTS 0.00 0.00

2022 520 ARCHITECTURAL COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

2022 530 PESTICIDES/FERTILIZERS 0.00 0.00

2022 540 ASPHALT PAVING / ROOFING 0.00 0.01

2022 610 RESIDENTIAL FUEL COMBUSTION 4.36 10.24

2022 620 FARMING OPERATIONS 0.00 2.13

2022 630 CONSTRUCTION AND DEMOLITION 0.00 7.76

2022 640 PAVED ROAD DUST 0.00 6.35

2022 645 UNPAVED ROAD DUST 0.00 3.57

2022 650 FUGITIVE WINDBLOWN DUST 0.00 0.11

2022 660 FIRES 0.01 0.07

2022 670 WASTE BURNING AND DISPOSAL 0.05 0.19

2022 690 COOKING 0.00 1.00

2022 ALL ON-ROAD MOBILE 18.12 2.05

2022 810 AIRCRAFT 2.95 0.10

2022 820 TRAINS 3.62 0.10

2022 840 RECREATIONAL BOATS 0.51 0.12

2022 850 OFF-ROAD RECREATIONAL VEHICLES 0.01 0.00

2022 860 OFF-ROAD EQUIPMENT 7.58 0.37

2022 870 FARM EQUIPMENT 0.64 0.03

2022 890 FUEL STORAGE AND HANDLING 0.00 0.00

2022 TOTALS: 42.20 35.86

CMB PM10 Source Categories (EIC SUM)

Adjusted 

MVEB

Adjusted 

Total

Motor Vehicles PM10 (On-Road Mobile, 810-870) 2.77

Wood Smoke PM10 (610, 660, 670) 10.50

Fugitive Dust PM10 (430, 620-650) 20.58 2.2 22.78

Total NOx 42.20 0.9 43.10

Total PM10 35.86

Note that the 2022 motor vehicle emission budgets (MVEB) for Fugitive Dust PM10 are increased by 1.5 tpd to allow for 

potential increases in Paved Road Dust and Road Construction Dust from 2022 to 2035. This additional increase may 

be needed for SACOG to make a transportation conformity determination for a horizon year of 2035 or later for 

transportation planning purposes when using the latest year of motor vehicle emissions budgets (2022) from the PM10

Maintenance Plan.

In addition, the increase in the motor vehicle emission budgets due to rounding up to the nearest integer is added to the

Fugitive Dust PM10 and Total NOx emission forecasts.

Fugitive Dust PM10: 16.3 rounds up to 17 = 0.7 increase

Total NOx: 18.1 rounds up to 19 = 0.9 increase
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Appendix A: Emissions Inventory 

Page A-5

Sacramento PM10 Maintenance Plan - 1990 Emissions Data (Tons/Day)

(Sacramento County Only)

CARB CEFS v.1.06

FYEAR

EIC 

SUM EICSUMN NOX PM10

1990 10 ELECTRIC UTILITIES 0.02 0.00

1990 20 COGENERATION 0.67 0.05

1990 30 OIL AND GAS PRODUCTION (COMBUSTION) 0.20 0.01

1990 50 MANUFACTURING AND INDUSTRIAL 0.92 0.03

1990 52 FOOD AND AGRICULTURAL PROCESSING 0.39 0.02

1990 60 SERVICE AND COMMERCIAL 2.72 0.20

1990 99 OTHER (FUEL COMBUSTION) 0.40 0.02

1990 110 SEWAGE TREATMENT 0.00 0.00

1990 120 LANDFILLS 0.00 0.00

1990 130 INCINERATORS 0.02 0.00

1990 199 OTHER (WASTE DISPOSAL) 0.00 0.39

1990 210 LAUNDERING 0.00 0.00

1990 220 DEGREASING 0.00 0.00

1990 230 COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

1990 240 PRINTING 0.00 0.00

1990 250 ADHESIVES AND SEALANTS 0.00 0.00

1990 299 OTHER (CLEANING AND SURFACE COATINGS) 0.00 0.00

1990 310 OIL AND GAS PRODUCTION 0.00 0.00

1990 330 PETROLEUM MARKETING 0.00 0.00

1990 410 CHEMICAL 0.01 0.06

1990 420 FOOD AND AGRICULTURE 0.00 0.16

1990 430 MINERAL PROCESSES 0.13 0.87

1990 440 METAL PROCESSES 0.01 0.01

1990 450 WOOD AND PAPER 0.00 0.27

1990 470 ELECTRONICS 0.00 0.00

1990 499 OTHER (INDUSTRIAL PROCESSES) 0.00 0.00

1990 510 CONSUMER PRODUCTS 0.00 0.00

1990 520 ARCHITECTURAL COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

1990 530 PESTICIDES/FERTILIZERS 0.00 0.00

1990 540 ASPHALT PAVING / ROOFING 0.00 0.01

1990 610 RESIDENTIAL FUEL COMBUSTION 4.83 10.24

1990 620 FARMING OPERATIONS 0.00 2.81

1990 630 CONSTRUCTION AND DEMOLITION 0.00 7.44

1990 640 PAVED ROAD DUST 0.00 5.92

1990 645 UNPAVED ROAD DUST 0.00 3.31

1990 650 FUGITIVE WINDBLOWN DUST 0.00 0.14

1990 660 FIRES 0.01 0.04

1990 670 MANAGED BURNING AND DISPOSAL 0.14 0.30

1990 690 COOKING 0.00 0.42

1990 ALL ON-ROAD MOBILE 92.61 2.46

1990 810 AIRCRAFT 0.73 0.04

1990 820 TRAINS 4.50 0.09

1990 840 RECREATIONAL BOATS 0.33 0.04

1990 850 OFF-ROAD RECREATIONAL VEHICLES 0.02 0.03

1990 860 OFF-ROAD EQUIPMENT 20.88 1.67

1990 870 FARM EQUIPMENT 3.16 0.22

1990 890 FUEL STORAGE AND HANDLING 0.00 0.00

1990 TOTALS: 132.69 37.27

CMB PM10 Source Categories (EIC SUM)

Motor Vehicles PM10 (On-Road Mobile, 810-870) 4.55

Wood Smoke PM10 (610, 660, 670) 10.58

Fugitive Dust PM10 (430, 620-650) 20.49

Note that these 1990 PM10 source emissions are adjusted to reflect updated CARB inventory

changes to Residential Fuel Combustion and Paved Road Dust per September 3, 2010 e-mail.

WINTER DAY
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Appendix A: Emissions Inventory 

Page A-6

Sacramento PM10 Maintenance Plan - 1995 Emissions Data (Tons/Day)

(Sacramento County Only)

CARB CEFS v.1.06 WINTER DAY

FYEAR

EIC 

SUM EICSUMN NOX PM10

1995 10 ELECTRIC UTILITIES 0.01 0.00

1995 20 COGENERATION 0.66 0.14

1995 30 OIL AND GAS PRODUCTION (COMBUSTION) 0.33 0.00

1995 50 MANUFACTURING AND INDUSTRIAL 0.85 0.04

1995 52 FOOD AND AGRICULTURAL PROCESSING 0.25 0.04

1995 60 SERVICE AND COMMERCIAL 1.81 0.18

1995 99 OTHER (FUEL COMBUSTION) 0.45 0.02

1995 110 SEWAGE TREATMENT 0.00 0.00

1995 120 LANDFILLS 0.00 0.00

1995 130 INCINERATORS 0.03 0.01

1995 199 OTHER (WASTE DISPOSAL) 0.01 0.09

1995 210 LAUNDERING 0.00 0.00

1995 220 DEGREASING 0.00 0.00

1995 230 COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

1995 240 PRINTING 0.00 0.00

1995 250 ADHESIVES AND SEALANTS 0.00 0.00

1995 299 OTHER (CLEANING AND SURFACE COATINGS) 0.00 0.00

1995 310 OIL AND GAS PRODUCTION 0.00 0.00

1995 330 PETROLEUM MARKETING 0.00 0.00

1995 410 CHEMICAL 0.02 0.00

1995 420 FOOD AND AGRICULTURE 0.00 0.22

1995 430 MINERAL PROCESSES 0.04 0.53

1995 440 METAL PROCESSES

1995 450 WOOD AND PAPER 0.00 0.24

1995 470 ELECTRONICS 0.00 0.00

1995 499 OTHER (INDUSTRIAL PROCESSES) 0.00 0.00

1995 510 CONSUMER PRODUCTS 0.00 0.00

1995 520 ARCHITECTURAL COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

1995 530 PESTICIDES/FERTILIZERS 0.00 0.00

1995 540 ASPHALT PAVING / ROOFING 0.00 0.01

1995 610 RESIDENTIAL FUEL COMBUSTION 4.58 9.79

1995 620 FARMING OPERATIONS 0.00 2.69

1995 630 CONSTRUCTION AND DEMOLITION 0.00 5.30

1995 640 PAVED ROAD DUST 0.00 5.98

1995 645 UNPAVED ROAD DUST 0.00 3.14

1995 650 FUGITIVE WINDBLOWN DUST 0.00 0.13

1995 660 FIRES 0.01 0.05

1995 670 WASTE BURNING AND DISPOSAL 0.15 0.37

1995 690 COOKING 0.00 0.47

1995 ALL ON-ROAD MOBILE 82.25 2.05

1995 810 AIRCRAFT 1.09 0.05

1995 820 TRAINS 4.56 0.09

1995 840 RECREATIONAL BOATS 0.35 0.04

1995 850 OFF-ROAD RECREATIONAL VEHICLES 0.02 0.03

1995 860 OFF-ROAD EQUIPMENT 18.08 1.16

1995 870 FARM EQUIPMENT 2.70 0.16

1995 890 FUEL STORAGE AND HANDLING 0.00 0.00

1995 TOTALS: 118.24 33.01

CMB PM10 Source Categories (EIC SUM)

Motor Vehicles PM10 (On-Road Mobile, 810-870) 3.58

Wood Smoke PM10 (610, 660, 670) 10.20

Fugitive Dust PM10 (430, 620-650) 17.77

Note that these 1995 PM10 source emissions are adjusted to reflect updated CARB inventory

changes to Residential Fuel Combustion and Paved Road Dust per September 3, 2010 e-mail.
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Appendix A: Emissions Inventory 

Page A-7

Sacramento PM10 Maintenance Plan - 2000 Emissions Data (Tons/Day)

(Sacramento County Only)

CARB CEFS v.1.06

FYEAR

EIC 

SUM EICSUMN NOX PM10

2000 10 ELECTRIC UTILITIES 0.40 0.15

2000 20 COGENERATION 0.02 0.01

2000 30 OIL AND GAS PRODUCTION (COMBUSTION) 0.05 0.01

2000 50 MANUFACTURING AND INDUSTRIAL 0.83 0.04

2000 52 FOOD AND AGRICULTURAL PROCESSING 0.30 0.02

2000 60 SERVICE AND COMMERCIAL 1.64 0.17

2000 99 OTHER (FUEL COMBUSTION) 0.49 0.03

2000 110 SEWAGE TREATMENT 0.00 0.00

2000 120 LANDFILLS 0.02 0.01

2000 130 INCINERATORS 0.01 0.00

2000 199 OTHER (WASTE DISPOSAL) 0.00 0.00

2000 210 LAUNDERING 0.00 0.00

2000 220 DEGREASING 0.00 0.00

2000 230 COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

2000 240 PRINTING 0.00 0.00

2000 250 ADHESIVES AND SEALANTS 0.00 0.00

2000 299 OTHER (CLEANING AND SURFACE COATINGS) 0.00 0.00

2000 310 OIL AND GAS PRODUCTION 0.00 0.00

2000 330 PETROLEUM MARKETING 0.00 0.00

2000 410 CHEMICAL 0.05 0.02

2000 420 FOOD AND AGRICULTURE 0.00 0.04

2000 430 MINERAL PROCESSES 0.14 0.59

2000 440 METAL PROCESSES 0.01 0.01

2000 450 WOOD AND PAPER 0.00 0.13

2000 470 ELECTRONICS 0.00 0.00

2000 499 OTHER (INDUSTRIAL PROCESSES) 0.00 0.11

2000 510 CONSUMER PRODUCTS 0.00 0.00

2000 520 ARCHITECTURAL COATINGS AND RELATED PROCESS SOLVENTS 0.00 0.00

2000 530 PESTICIDES/FERTILIZERS 0.00 0.00

2000 540 ASPHALT PAVING / ROOFING 0.00 0.01

2000 610 RESIDENTIAL FUEL COMBUSTION 4.32 9.34

2000 620 FARMING OPERATIONS 0.00 2.54

2000 630 CONSTRUCTION AND DEMOLITION 0.00 6.53

2000 640 PAVED ROAD DUST 0.00 6.03

2000 645 UNPAVED ROAD DUST 0.00 3.14

2000 650 FUGITIVE WINDBLOWN DUST 0.00 0.13

2000 660 FIRES 0.01 0.05

2000 670 MANAGED BURNING AND DISPOSAL 0.13 0.28

2000 690 COOKING 0.00 0.52

2000 ALL ON-ROAD MOBILE 63.26 1.90

2000 810 AIRCRAFT 1.72 0.07

2000 820 TRAINS 4.90 0.10

2000 840 RECREATIONAL BOATS 0.34 0.05

2000 850 OFF-ROAD RECREATIONAL VEHICLES 0.01 0.01

2000 860 OFF-ROAD EQUIPMENT 19.11 1.23

2000 870 FARM EQUIPMENT 2.34 0.14

2000 890 FUEL STORAGE AND HANDLING 0.00 0.00

2000 TOTALS: 100.11 33.36

CMB PM10 Source Categories (EIC SUM)

Motor Vehicles PM10 (On-Road Mobile, 810-870) 3.50

Wood Smoke PM10 (610, 660, 670) 9.67

Fugitive Dust PM10 (430, 620-650) 18.96

Note that these 2000 PM10 source emissions are adjusted to reflect updated CARB inventory

changes to Residential Fuel Combustion and Paved Road Dust per September 3, 2010 e-mail.

WINTER DAY
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Appendix B: Control Measures 

Page B-1 

Appendix B: Control Measures 

The following fugitive dust measures are considered to be potential reasonably 

available control measures (RACM) for PM10: 

Source Category Control Action 

Paved Roads Improved sanding/salting applications/materials 

Truck covering 

Construction site measures 

Curb installation and shoulder stabilization 

Storm water drainage 

Unpaved Roads Paving and surface improvements (graveling) 

Chemical stabilization 

Traffic reduction plans 

Vehicle speed reduction 

Storage Piles (Transfer Operations) Wet suppression and dust control 

Construction/Demolition Paving permanent roads early in project 

Truck covering 

Access apron construction and cleaning 

Watering of graveled travel surfaces 

Open Area Wind Erosion Revegetation 

Limitation of off-road vehicle traffic 

Limitation of leafblowers 

Agricultural Tilling Land conservation practices 

The following residential wood combustion control measures are considered to be 

potential reasonably available control measures for PM10: 

Source Category Control Action 

Integral Measures Public awareness/education and voluntary curtailment 

program 

Mandatory curtailment during predicted periods of high 

PM10 concentrations 

New stoves EPA-certified Phase II 

Improved wood burning performance 

 Control of wood moisture content

 Weatherization of homes with wood stoves  Educational opacity program

Existing Installations Convert wood-burning fireplaces to gas logs 

Changeover to EPA-certified Phase II stoves or low 

emitting stoves 

New Installations Gas fireplaces or gas logs in new installations 

Upgrade offset 

Restriction on number or density of new stove and 

fireplace installations 

Requirement that new stove installations are low emitting 

New and Existing Installations Device offset and upgrade offset 
PM10 Implementation/Maintenance Plan and 

Redesignation Request for Sacramento County October 28, 2010

Appendix C: Transportation Conformity Budgets 

Page C-1

Appendix C: Transportation Conformity Budgets 

Sacramento County PM10 Maintenance Plan 

Transportation Conformity Budgets 

Average Winter Day 

Tons per Winter Day 

Sacramento County 2008 2012 2022 

NOX PM10 NOX PM10 NOX PM10

Direct Exhaust

(includes tire and brake wear for PM10) 49.6 2.2 37.6 2.1 18.1 2.1 

Paved Road Dust --- 6.1 --- 6.2 --- 6.4 + 1.0

Unpaved Road Dust --- 3.6 --- 3.6 --- 3.6 

Road Construction Dust --- 2.7 --- 2.8 --- 2.8 + 0.5

Total 49.6 14.6 37.6 14.6 18.1 14.8 + 1.5

Total (rounded up to nearest ton) 50 15 38 15 19 17 

Notes: 

1. An additional 1.5 tons per day of PM10 was added to the 2022 PM10 budgets in order to account for

potential increases in Paved Road Dust and Road Construction Dust beyond 2022. This additional 

increase may be needed for SACOG to make a transportation conformity determination for a horizon year 

of 2035 or later for transportation planning purposes when using the latest year of motor vehicle 

emissions budgets (2022) in the PM10 Maintenance Plan. 

2. The additional increase in 1.0 ton per day of PM10 to Paved Road Dust and 0.5 ton per day of PM10 to

Road Construction Dust in the 2022 transportation budgets are accounted for in the maintenance 

demonstration emission forecasts for Fugitive Dust PM10 to ensure consistency with the maintenance 

demonstration. 

3. The additional increase in the 2008, 2012, and 2022 NOX and PM10 transportation budgets due to

rounding up to the nearest ton are accounted for in the maintenance demonstration emission forecasts for 

Total NOX and Fugitive Dust PM10 to ensure consistency with the maintenance demonstration. 

4. If the proposed MVEBs are determined to be adequate by EPA, future transportation plans will need to

conform to these motor vehicle emissions budgets in any future transportation plan amendment and 

updates. SACOG must ensure that the aggregate wintertime transportation emissions in Sacramento 

County (including, but not limited to, vehicle emissions, dust from paved and unpaved roads and road 

construction), rounded up to the nearest integer, do not exceed these levels when approving new 

metropolitan transportation plans and transportation improvement programs, even if the mix of projects 

changes or growth increases.