The EPA Acting Regional Administrator, Alexis Strauss signed the following 

proposed rule on July 12, 2013 and EPA is submitting it for publication in 

the Federal Register (FR). While we have taken steps to ensure the accuracy 

of this Internet version of the proposed rule, it is not the official version 

of the proposal for purposes of public comment. Please refer to the official 

version in a forthcoming FR publication appearing on the Government Printing 

Office’s FDsys website, http://fdsys.gpo.gov/fdsys/search/home.action and on 

Regulation.gov in Docket Number EPA-R09-OAR-2012-0877, 

http://www.regulations.gov

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Billing Code: 6560-50-P

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R09-OAR-2012-0877;_________]

Approval and Promulgation of Implementation Plans; Designation 

of Areas for Air Quality Planning Purposes; State of California; 

PM10; Redesignation of Sacramento to Attainment; Approval of PM10

Redesignation Request and Maintenance Plan for Sacramento

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

SUMMARY: EPA is proposing to approve, as a revision of the 

California state implementation plan, the State's request to 

redesignate the Sacramento nonattainment area to attainment for 

the 24-hour particulate matter of ten microns or less (PM10) 

National Ambient Air Quality Standard (NAAQS). EPA is also 

proposing to approve the PM10 maintenance plan and the associated 

motor vehicle emissions budgets for use in transportation 

conformity determinations necessary for the Sacramento area. 

Finally, EPA is proposing to approve the attainment year 

emissions inventory. EPA is proposing these actions because the 

SIP revision meets the requirements of the Clean Air Act and EPA 

guidance for such plans and motor vehicle emissions budgets.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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DATES: Comments must be received on or before [Federal Register: 

Insert date 30 days after the publication date].

ADDRESSES: Submit your comments, identified by Docket ID Number 

EPA-R09-OAR-2012-0877, by one of the following methods:

1. http://www.regulations.gov: Follow the on-line 

instructions for submitting comments.

2. Email: ungvarsky.john@epa.gov

3. Mail or deliver: John Ungvarsky (AIR-2), U.S. 

Environmental Protection Agency, Region IX, 75 Hawthorne Street, 

San Francisco, CA 94105-3901. Deliveries are only accepted 

during the Regional Office's normal hours of operation.

Instructions: All comments will be included in the public docket 

without change and may be made available online at 

http://www.regulations.gov, including any personal information 

provided, unless the comment includes Confidential Business 

Information (CBI) or other information whose disclosure is 

restricted by statute. Information that you consider CBI or 

otherwise protected should be clearly identified as such and 

should not be submitted through http://www.regulations.gov or 

email. http://www.regulations.gov is an anonymous access system, 

and EPA will not know your identity or contact information 

unless you provide it in the body of your comment. If you send 

email directly to EPA, your email address will be automatically 

captured and included as part of the public comment. If EPA 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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cannot read your comment due to technical difficulties and 

cannot contact you for clarification, EPA may not be able to 

consider your comment.

Docket: The index to the docket and documents in the docket 

for this action are generally available electronically at 

www.regulations.gov and in hard copy at EPA Region IX, 75 

Hawthorne Street, San Francisco, California. While all documents 

in the docket are listed at www.regulations.gov, some 

information may be publicly available only at the hard copy 

location (e.g., copyrighted material, large maps), and some may 

not be publicly available in either location (e.g., CBI). To 

inspect the hard copy materials, please schedule an appointment 

during normal business hours with the contact listed in the FOR 

FURTHER INFORMATION CONTACT section.

FOR FURTHER INFORMATION CONTACT: John Ungvarsky, Air Planning 

Office (AIR-2), U.S. Environmental Protection Agency, Region IX, 

(415) 972-3963, ungvarsky.john@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document, whenever 

“we,” “us,” or “our” is used, we mean EPA. This supplementary 

information section is arranged as follows:

Table of Contents

I. Summary of Today's Proposed Action

II. Background

A. The PM10 NAAQS
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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B. PM10 Planning Requirements

III. Procedural Requirements for Adoption and Submittal of SIP 

Revisions

IV. Substantive Requirements for Redesignation

V. Evaluation of the State's Redesignation Request for the 

Sacramento PM10 Nonattainment Area 

A. Determination That the Area Has Attained the PM10 NAAQS.

B. The Area Must Have a Fully-Approved SIP Meeting 

Requirements Applicable for Purposes of Redesignation under 

Clean Air Act Section 110 and Part D.

1. Basic SIP Requirements under Section 110

2. SIP Requirements under Part D

C. EPA Has Determined That the Improvement in Air Quality is 

Due to Permanent and Enforceable Reductions in Emissions.

D. The Area Must Have a Fully Approved Maintenance Plan under 

Clean Air Act Section 175A.

1. Attainment Inventory

2. Maintenance Demonstration

3. Verification of Continued Attainment

4. Contingency Provisions

5. Subsequent Maintenance Plan Revisions

6. Transportation Conformity and Motor Vehicle Emissions 

Budgets

VI. Proposed Action and Request for Public Comment
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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VII. Statutory and Executive Order Reviews

I. Summary of Today's Proposed Action

Under Clean Air Act (CAA or “the Act”) section 

107(d)(3)(D), EPA is proposing to approve the State’s request to 

redesignate the Sacramento PM10 nonattainment area to attainment 

for the 24-hour PM10 National Ambient Air Quality Standard (NAAQS

or “standard”). We are doing so based on our conclusion that the 

area has met the five criteria for redesignation under CAA 

section 107(d)(3)(E): 1) that the area has attained the 24-hour 

PM10 NAAQS in the 2010-2012 time period and that the area 

continues to attain the PM10 standard since that time; 2) that 

relevant portions of the California state implementation plan 

(SIP) are fully approved; 3) that the improvement in air quality 

is due to permanent and enforceable reductions in emissions; 4) 

that California has met all requirements applicable to the 

Sacramento PM10 nonattainment area with respect to section 110 

and part D of the CAA; and 5) that the PM10

Implementation/Maintenance Plan and Redesignation Request for 

Sacramento County (October 28, 2010) (“Sacramento PM10

Maintenance Plan” or “Plan”)

1 meets the requirements of section 

175A of the CAA.

 

1 See letter, James N. Goldstene, Executive Officer, to Jared Blumenfeld, 

Regional Administrator, EPA Region 9, dated December 7, 2010, with 

attachments.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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In addition, under CAA section 110(k)(3), EPA is proposing 

to approve the maintenance plan including the motor vehicle 

emissions budgets (MVEBs) in the 2008 Sacramento PM10 Plan as a 

revision to the California SIP because we find the MVEBs meet 

the applicable transportation conformity requirements under 40 

CFR 93.118(e). EPA finds that the maintenance demonstration 

shows how the area will continue to attain the 24-hour PM10 NAAQS 

for at least 10 years beyond redesignation (i.e., through 2023)

and that the contingency provisions describing the actions that 

the Sacramento Metropolitan Air Quality Management District 

(SMAQMD) will take in the event of a future monitored violation 

meet all applicable requirements for maintenance plans and 

related contingency provisions in CAA section 175A. Finally, EPA 

is proposing to approve the attainment year emissions inventory 

under CAA section 172(c)(3).

EPA is proposing these actions because the SIP revision 

meets the requirements of the CAA and EPA guidance for such 

plans and budgets.

II. Background

A. The PM10 NAAQS

EPA sets the NAAQS for certain ambient air pollutants at 

levels required to protect public health and welfare. 

Particulate matter with an aerodynamic diameter less than or 

equal to a nominal ten micrometers, or PM10, is one of these 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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ambient air pollutants for which EPA has established healthbased standards. 

EPA revised the NAAQS for particulate matter on July 1, 

1987 (52 FR 24633), replacing standards for total suspended 

particulates (TSP less than 30 microns in diameter) with new 

standards applying only to particulate matter up to 10 microns 

in diameter (PM10). At that time, EPA established two PM10

standards, an annual standard and a 24-hour standard. 

In an October 17, 2006 PM NAAQS revision, the 24-hour PM10

standards were retained but the annual standards were revoked

effective December 18, 2006. 71 FR 61144 (October 17, 2006). On 

January 15, 2013, EPA announced that it was again retaining the 

24-hour PM10 NAAQS as a 24-hour standard of 150 micrograms per 

cubic meter (ug/m3). See 78 FR 3086. This SIP submittal addresses 

the 24-hour PM10 standard as originally promulgated in 1987 and 

reaffirmed on January 15, 2013. An area attains the 24-hour PM10

standard of 150 micrograms per cubic meter (ug/m3) when the 

expected number of days per calendar year with a 24-hour

concentration in excess of the standard (referred to as an 

exceedance), is equal to or less than one.2

B. PM10 Planning Requirements

 

2 An exceedance is defined as a daily value that is above the level of the 24-

hour standard, 150 μg/m3, after rounding to the nearest 10 μg/m3 (i.e., values 

ending in five or greater are to be rounded up). Thus, a recorded value of 

154 μg/m3 would not be an exceedance since it would be rounded to 150 μg/m3; 

whereas, a recorded value of 155 μg/m3 would be an exceedance since it would 

be rounded to 160 μg/m3. See 40 CFR part 50, Appendix K, section 1.0.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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Effective January 20, 1994, EPA designated Sacramento 

County as a moderate nonattainment area for the PM10 NAAQS. See 

58 FR 67334 (December, 21, 1993). The designation, 

classification, and boundaries of the Sacramento nonattainment 

area are codified at 40 CFR 81.305.

Beginning in the 1970’s and continuing to the present, the 

SMAQMD3 and CARB have adopted a number of rules and prepared a 

number of nonattainment plans to address planning requirements 

under the CAA, as amended in 1977. CARB submitted these rules 

and plans to EPA at various times, and EPA approved a number of 

them into the California SIP. Examples of rules adopted by 

SMAQMD and approved by EPA as revisions to the California SIP as 

part of the PM10 control strategy in the Sacramento PM10

nonattainment area include: Rule 403 - Fugitive Dust; Rule 405 -

Dust and Condensed Fumes; Rule 412 - Stationary Source Internal 

Combustion Engines at Major Stationary Sources of NOx; and Rule 

414 - Natural Gas Fired Water Heaters. Examples of rules adopted 

by CARB and approved by EPA as revisions to the California SIP 

that have reduced PM10 in the Sacramento PM10 nonattainment area 

include: California Code of Regulations (CCR) Title 13, Section 

1956.8 - Heavy Duty Vehicle Exhaust Emission Standards; CCR, 

Section 2262 - California Reformulated Gasoline Phase 2 and 

 

3 In 1990, the Sacramento County Air Pollution Control District changed its 

name to the Sacramento Metropolitan Air Quality Management District.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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Phase 3 Standards; and CCR, Sections 2420-2427 - Heavy Duty 

Diesel Cycle Engines.

On February 15, 2002, EPA determined under section 179(c)

of the CAA that the Sacramento PM10 nonattainment area had 

attained the 24-hour PM10 NAAQS by its December 31, 2000 

attainment date, based on complete, quality-assured, and 

certified ambient air monitoring data that showed the area 

monitored attainment of the 24-hour PM10 NAAQS for 1998-2000. (67 

FR 7082). Because EPA determined that the Sacramento PM10

nonattainment area met its attainment date, no PM10 serious 

nonattainment area requirements apply in the Sacramento PM10

nonattainment area. In this action, we are updating the 

determination of attainment to account for PM10 monitoring data 

since 2001, including more recent years consistent with the 

applicable criterion for redesignation under CAA section 

107(d)(3)(E)(i).

On December 7, 2010, CARB submitted the Sacramento PM10

Maintenance Plan and requested that EPA redesignate the 

Sacramento PM10 nonattainment area to attainment for the 24-hour 

PM10 NAAQS. We are proposing action today on CARB’s December 7, 

2010 submittal, including the Sacramento PM10 Maintenance Plan

and redesignation request.

III. Procedural Requirements for Adoption and Submittal of SIP 

Revisions
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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Sections 110(a)(1) and 110(l) of the Act require states to 

provide reasonable notice and public hearing prior to adoption 

of SIP revisions. In this action, we are proposing action on 

CARB's December 7, 2010 submittal of the Sacramento PM10

Maintenance Plan, dated October 28, 2010, as a revision to the 

California SIP. The submittal documents the public review 

process followed by SMAQMD and CARB in adopting the Sacramento 

PM10 Maintenance Plan prior to submittal to EPA as a revision to 

the California SIP. The documentation provides evidence that 

reasonable notice of a public hearing was provided to the public 

and that a public hearing was conducted prior to adoption.

CARB’s submittal includes a letter dated October 28, 2010 

from Larry Greene, Executive Director / Air Pollution Control 

Officer to the Board of Directors for the SMAQMD. In addition, 

Enclosure 1, Attachment 3 of CARB’s submittal includes a copy of 

the notice to the public published on September 27, 2010, 

announcing a public hearing to be held on October 28, 2010. 

These materials document the public review process followed by 

SMAQMD in adopting the Sacramento PM10 Maintenance Plan prior to 

transmittal to CARB and provide evidence that reasonable notice 

of a public hearing was provided to the public and that a public 

hearing was conducted prior to adoption. Specifically, the 

notice for the Board hearing was published in the Sacramento 

Bee, a newspaper of general circulation, on September 27, 2010 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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and sent to over 2000 e-mail addresses. The Sacramento PM10

Maintenance Plan was also made available for viewing on the 

District's website and at the District office on and after 

September 27, 2010. 

Enclosure I, Attachment 1 of CARB’s submittal documents the 

adoption of the Sacramento PM10 Plan by the SMAQMD Board of 

Directors. On October 28, 2010, the SMAQMD Board of Directors 

approved the Sacramento PM10 Maintenance Plan and directed SMAQMD 

staff to forward the Plan to CARB, the Governor of California’s

designee for SIP matters. 

Enclosure IV of CARB’s submittal documents CARB’s board 

resolution regarding the Sacramento PM10 Plan. On December 7, 

2010, CARB submitted the Sacramento PM10 Maintenance Plan to EPA 

for approval as a revision to the California SIP.

Based on the documentation included in CARB’s submittal, we 

find that the submittal of the Sacramento PM10 Maintenance Plan

as a SIP revision satisfies the procedural requirements of 

sections 110(l) of the Act for revising SIPs. 

CAA section 110(k)(1)(B) requires EPA to determine whether 

a SIP submittal is complete within 60 days of receipt. This 

section also provides that any plan that we have not 

affirmatively determined to be complete or incomplete will 

become complete six months after the day of submittal by 

operation of law. A completeness review allows us to determine 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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if the submittal includes all the necessary items and 

information we need to act on it. 

We make completeness determinations using criteria we have 

established in 40 CFR part 51, Appendix V. These criteria fall 

into two categories: administrative information and technical 

support information. The administrative information provides 

documentation that the State has followed basic administrative 

procedures during the SIP-adoption process and thus we have a 

legally-adopted SIP revision in front of us. The technical 

support information provides us the information we need to 

determine the impact of the proposed revision on attainment and 

maintenance of the air quality standards. 

We notify a state of our completeness determination by 

letter unless the submittal becomes complete by operation of 

law. A finding of completeness does not approve the submittal as 

part of the SIP nor does it indicate that the submittal is 

approvable. It does start a 12-month clock for EPA to act on the 

SIP submittal. See CAA section 110(k)(2). The Sacramento PM10

Maintenance Plan became complete by operation of law on June 7,

2011.

IV. Substantive Requirements for Redesignation

The CAA establishes the requirements for redesignation of a 

nonattainment area to attainment. Specifically, section 

107(d)(3)(E) allows for redesignation provided that the 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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following criteria are met: (1) EPA determines that the area has 

attained the applicable NAAQS; (2) EPA has fully approved the 

applicable implementation plan for the area under section 

110(k); (3) EPA determines that the improvement in air quality 

is due to permanent and enforceable reductions in emissions 

resulting from implementation of the applicable SIP, applicable 

federal air pollution control regulations, and other permanent 

and enforceable reductions; (4) EPA has fully approved a 

maintenance plan for the area as meeting the requirements of CAA 

section 175A; and (5) the State containing such area has met all 

requirements applicable to the area under section 110 and part D 

of the CAA. 

EPA provided guidance on redesignations in a document 

entitled, “State Implementation Plans; General Preamble for the 

Implementation of Title I of the Clean Air Act Amendments of 

1990,” published in the Federal Register on April 16, 1992 (57 

FR 13498), and supplemented on April 28, 1992 (57 FR 18070) 

(referred to herein as the “General Preamble”). Other relevant 

EPA guidance documents include: “Procedures for Processing 

Requests to Redesignate Areas to Attainment,” Memorandum from 

John Calcagni, Director, Air Quality Management Division, EPA 

Office of Air Quality Planning and Standards, September 4, 1992 

(referred to herein as the “Calcagni memorandum”); “Part D New 

Source Review (part D NSR) Requirements for Areas Requesting 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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Redesignation to Attainment,” Memorandum from Mary D. Nichols, 

Assistant Administrator for Air and Radiation, October 14, 1994 

(Nichols memorandum); and “State Implementation Plans for 

Serious PM10 Nonattainment Areas, and Attainment Date Waivers for 

PM10 Nonattainment Areas Generally; Addendum to the General 

Preamble for the Implementation of title I of the Clean Air Act 

Amendments of 1990,” 59 FR 41998 (August 16, 1994) (PM10

Addendum).

In this proposed rulemaking action, EPA applies these 

policies to the Sacramento PM10 Maintenance Plan, taking into 

consideration the specific factual issues presented. For the 

reasons set forth below in section V of this document, we 

propose to approve CARB’s request for redesignation of the 

Sacramento PM10 nonattainment area to attainment for the 24-hour

PM10 NAAQS based on our conclusion that all of the criteria under 

CAA section 107(d)(3)(E) have been satisfied. 

V. Evaluation of the State's Redesignation Request for the 

Sacramento PM10 Nonattainment Area

A. Determination That the Area Has Attained the PM10 NAAQS.

CAA section 107(d)(3)(E)(i) states that for an area to be 

redesignated to attainment, EPA must determine that the area has 

attained the relevant NAAQS. In this case, the relevant NAAQS is 

the 24-hour PM10 NAAQS.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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Generally, EPA determines whether an area’s air quality is 

meeting the 24-hour PM10 NAAQS based upon complete,4 qualityassured, and certified data gathered at established state and 

local air monitoring stations (SLAMS) in the nonattainment area 

and entered into the EPA Air Quality System (AQS) database. Data 

from air monitors operated by state, local, or tribal agencies 

in compliance with EPA monitoring requirements must be submitted 

to AQS. These monitoring agencies certify annually that these 

data are accurate to the best of their knowledge. Accordingly, 

EPA relies primarily on data in AQS when determining the 

attainment status of an area. See 40 CFR 50.6; 40 CFR part 50, 

appendices J and K; 40 CFR part 53; and, 40 CFR part 58, 

appendices A, C, D, and E.5 EPA will also consider air quality 

data from other air monitoring stations in the nonattainment 

area provided those stations meet the federal monitoring 

requirements for SLAMS, including the quality assurance and 

quality control criteria in 40 CFR part 58, appendix A. See 40 

CFR 58.14 (2006) and 58.20 (2007);6 71 FR 61236, 61242; (October 

17, 2006). All valid data are reviewed to determine the area’s 

 

4 For PM10, a complete set of data includes a minimum of 75 percent of the 

scheduled PM10 samples per quarter. See 40 CFR part 50, Appendix K, section 

2.3(a).

5 Because the annual PM10 standard was revoked effective December 18, 2006, 

this document discusses only attainment of the 24-hour PM10 standard. See 71 

FR 61144; (October 17, 2006).

6 EPA promulgated amendments to the ambient air monitoring regulations in 40 

CFR parts 53 and 58 on October 17, 2006. (See 71 FR 61236.) The requirements 

for Special Purpose Monitors were revised and moved from 40 CFR 58.14 to 40 

CFR 58.20.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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air quality status in accordance with 40 CFR part 50, appendix 

K.

Attainment of the 24-hour PM10 standard is determined by 

calculating the expected number of exceedances of the standard 

in a year. The 24-hour PM10 standard is attained when the 

expected number of exceedances averaged over a three-year period 

is less than or equal to one at each monitoring site within the 

nonattainment area. Generally, three consecutive years of air 

quality data are required to show attainment of the 24-hour PM10

standard. See 40 CFR part 50 and appendix K.

To demonstrate attainment of the 24-hour PM10 standard at a 

monitoring site, the monitor must provide sufficient data to 

perform the required calculations in 40 CFR part 50, appendix K. 

The amount of data required varies with the sampling frequency, 

data capture rate, and the number of years of record. For PM10, a 

“complete” set of data includes a minimum of 75 percent of the 

scheduled PM10 samples per quarter. See 40 CFR part 50, appendix 

K, section 2.3(a). In all cases, three years of representative 

monitoring data that meet the 75 percent criterion should be 

utilized, if available. More than three years may be considered 

if all additional representative years of data meeting the 75 

percent criterion are utilized. Data not meeting these criteria 

may also suffice to show attainment; however, such exceptions 

must be approved by the appropriate Regional Administrator in 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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accordance with EPA guidance. See 40 CFR part 50, appendix K, 

section 2.3.

In the Sacramento PM10 nonattainment area, the agencies 

responsible for assuring that the area meets air quality 

monitoring requirements include CARB and SMAQMD. Both CARB and 

SMAQMD submit annual monitoring network plans to EPA. SMAQMD 

network plans describe the monitoring network operated by SMAQMD 

and CARB in Sacramento County, and CARB’s network plans describe 

the monitoring sites CARB operates. These plans discuss the 

status of the air monitoring network, as required under 40 CFR 

58.10.

EPA regularly reviews these annual plans for compliance 

with the applicable reporting requirements in 40 CFR part 58. 

With respect to PM10, EPA has found that the area’s network 

plans, submitted by CARB and SMAQMD, meet the applicable 

requirements under 40 CFR part 58. See EPA letters to CARB and 

SMAQMD approving their annual network plans for years 2010, 

2011, and 2012.7,8 EPA also concluded from its Technical System 

 

7 Letter from Matthew Lakin, Manager, Air Quality Analysis Office, U.S. EPA 

Region IX, to Karen Magliano, Chief, Air Quality Data Branch, Planning and 

Technical Support Division, CARB (October 29, 2010) (approving CARB’s “2010 

Annual Monitoring Network Plan for the Small Districts in California”); 

Letter from Matthew Lakin, Manager, Air Quality Analysis Office, U.S. EPA 

Region IX, to Karen Magliano, Chief, Air Quality Data Branch, Planning and 

Technical Support Division, CARB (November 1, 2011) (approving CARB’s “2011 

Annual Monitoring Network Plan for the Small Districts in California”); 

Letter from Matthew Lakin, Manager, Air Quality Analysis Office, U.S. EPA 

Region IX, to Karen Magliano, Chief, Air Quality Data Branch, Planning and 

Technical Support Division, CARB (April 19, 2013) (approving CARB’s “2012

Annual Monitoring Report for the Small Districts in California”).
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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Audit of the CARB Primary Quality Assurance Organization (PQAO) 

(conducted during the summer of 2011), that the combined ambient 

air monitoring network operated by CARB and the local air 

districts in their PQAO (which includes SMAQMD) currently meets 

or exceeds the requirements for the minimum number of SLAMS for 

PM10 in the Sacramento nonattainment area.9 CARB annually 

certifies that the data it submits to AQS are complete and 

quality-assured.10

There are two types of PM10 monitors used throughout the 

Sacramento PM10 nonattainment area monitoring network: the 

Federal Reference Method (FRM) filter-based high-volume sizeselective inlet sampler (hi-vols or SSI), and the Federal 

Equivalent Method (FEM) tapered element oscillating microbalance 

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

for PM10 sample collection is one in six days for the FRM filter-

 

8 Letter from Matthew Lakin, Manager, Air Quality Analysis Office, U.S. EPA 

Region IX, to Larry Greene, Air Pollution Control Officer, SMAQMD (November 

1, 2010) (approving the “Sacramento Metropolitan Air Quality Management 

District’s 2010 Annual Monitoring Network Plan”); Letter from Matthew Lakin, 

Manager, Air Quality Analysis Office, U.S. EPA Region IX, to Larry Greene, 

Air Pollution Control Officer, SMAQMD (October 31, 2011) (approving the 

“Sacramento Metropolitan Air Quality Management District’s 2011 Annual 

Monitoring Network Plan”); Letter from Matthew Lakin, Manager, Air Quality 

Analysis Office, U.S. EPA Region IX, to Larry Greene, Air Pollution Control 

Officer, SMAQMD (March 1, 2013) (approving the “Sacramento Metropolitan Air 

Quality Management District’s 2012 Annual Monitoring Network Plan”).

9 See letter from Deborah Jordan, Director, Air Division, U.S. EPA Region IX, 

to James Goldstene, Executive Officer, CARB, transmitting ”System Audit of 

the Ambient Monitoring Program: California Resources Board, June-September: 

2011,” with enclosure, October 22, 2012.

10 See, e.g., letter from Sylvia Vanderspek, Chief, Air Quality Data Branch, 

Planning and Technical Support Division, CARB, to Jared Blumenfeld, Regional 

Administrator, U.S. EPA Region IX, certifying calendar year 2012 ambient air 

quality data and quality assurance data, May 16, 2013.
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the accuracy of this version, but it is not the official version.

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based high volume samplers, while the FEM TEOM monitors operate 

on a daily 24-hour schedule.

There were six PM10 monitoring sites within the Sacramento 

PM10 nonattainment area in calendar years 2010, 2011, and 2012. 

SMAQMD operates five of the monitoring sites: Goldenland Court, 

North Highlands, Del Paso Manor, Branch Center Rd #2, and 

Stockton Blvd. CARB operates the T Street monitoring site. FRM 

filter-based high-volume samplers are located at all of the six 

sites listed above. Del Paso Manor and the Stockton Blvd utilize 

both the FRM filter-based samplers and FEM TEOM monitors.11 EPA 

defines specific monitoring site types and spatial scales of 

representativeness to characterize the nature and location of 

required monitors. For the six sites, the spatial scale is 

neighborhood scale, and the monitoring objective is population 

exposure, except the T Street site, which has a monitoring 

objective of highest concentration.12

Consistent with the requirements contained in 40 CFR part 

50, EPA has reviewed the quality-assured, and certified PM10

ambient air monitoring data as recorded in AQS for the 

applicable monitoring period collected at the monitoring sites 

in the Sacramento nonattainment area and determined that the 

data are complete.

 

11 A map of the locations of Sacramento County monitoring stations is found in 

Figure 3.2 of the Sacramento PM10 Plan.

12 See footnotes 7 and 8.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

20

Table 1 summarizes the site-specific highest 24-hour PM10

concentrations for the period of 2001-2012. As shown in Table 1, 

only one of the highest concentrations exceeded the 24-hour PM10

NAAQS standard of 150 μg/m3. Table 2 summarizes the expected 

number of exceedances occurring over three-year periods dating 

back to EPA’s previous clean data determination. See 67 FR 7082

(February 15, 2002). The 24-hour PM10 standard is attained when 

the expected number of exceedances averaged over a three-year 

period is less than or equal to one at each monitoring site 

within the nonattainment area. The highest value in Table 2 is 

0.3 exceedances over a three-year period, and the Sacramento PM10 

nonattainment area did not violate the 24-hour PM10 NAAQS during 

the 2001-2012 period. Therefore, we are proposing to determine, 

based on the complete, quality-assured data for three most 

recent years (2010-2012) that the Sacramento PM10 nonattainment 

area has attained the 24-hour PM10 standard. There are six PM10

monitors currently operating in the nonattainment area. 

Preliminary SLAMS data for 2013 from these monitors are also 

consistent with continued attainment.
The EPA Acting Regional Administrator, Alexis Strauss signed the following proposed rule on July 12, 2013

and EPA is submitting it for publication in the Federal Register (FR). While we have taken steps to ensure 

the accuracy of this Internet version of the proposed rule, it is not the official version of the proposal 

for purposes of public comment. Please refer to the official version in a forthcoming FR publication 

appearing on the Government Printing Office’s FDsys website, http://fdsys.gpo.gov/fdsys/search/home.action

and on Regulation.gov in Docket Number EPA-R09-OAR-2012-0877, http://www.regulations.gov

21

Table 1: Summary of Highest 24-hour PM10 Concentrations (μg/m3) from Ambient Data Collected within the 

Sacramento PM10 Nonattainment Area, 2001-2012.a

Site AQS Monitor ID

Highest Concentration (μg/m3)

2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

North HighlandsBlackfoot 06-067-0002-1 64 53 62 44 110 65 56 97 33 48 65 34

Sacramento-Del 

Paso Manor

06-067-0006-1 68 86 53 38 71 63 70 71 45 44 62 41

06-067-0006-3 65 43 43 101 49 132 66 92 39 19 NA NA

Branch Center 

Road #1b 06-067-0283-1 78 77 75 45 61 38 NA NA NA NA NA NA

Branch Center 

Road #2b 06-067-0284-1 NA NA NA NA NA 81 56 89 76 62 69 60

SacramentoAirport Road

c

06-067-0013-1 73 144 NA 35 56 90 94 71 NA NA NA NA

06-067-0013-2 51 73 57 47 NA NA NA NA NA NA NA NA

Sacramento Health 

Dept.-Stockton 

Blvd

06-067-4001-2 58 85 53 44 64 56 56 88 45 45 60 34

06-067-4001-3 122 103 73 91 70 159 51 92 44 50 73 37

SacramentoGoldenland Courtc

06-067-0014-1 NA NA NA NA NA NA NA 56 48 42 63 32

06-067-0014-3 NA NA NA NA NA NA NA NA NA 55 69 76

Sacramento-T 

Street

06-067-0010-1 89 77 65 58 53 109 53 73 47 53 38 36

06-067-0010-2 73 86 NA NA NA NA NA NA NA NA NA NA

06-067-0010-3 48 NA NA NA NA NA NA NA NA NA NA NA

a The data in this table are from AQS QuickLook Reports dated January 10, 2013 and June 7, 2013. 

b The Branch Center Road #1 monitor was replaced by the Branch Center Road #2 monitor, located .25 mi to the 

north, in early 2006.

c

The Airport Road site was relocated to the Goldenland Court site in August 2008.

NA: data are not available.
This document is a prepublication version signed by EPA Acting Regional Administrator Alexis Strauss on 

July 12, 2013. We have taken steps to ensure the accuracy of this version, but it is not the official 

version.

22

Table 2: Summary of Expected Exceedances 3-yr Average from Ambient Data Collected within the Sacramento PM10

Nonattainment Area, 2001-2012.a 

Site Name Site (AQS 

Monitor ID)

Expected Exceedances 3-yr Average

1999

-

2001

2000

-

2002

2001

-

2003

2002

-

2004

2003

-

2005

2004

-

2006

2005

-

2007

2006

-

2008

2007

-

2009

2008

-

2010

2009

-

2011

2010

-

2012

North HighlandsBlackfoot 06-067-0002-1 0 0 0 0 0 0 0 0 0 0 0 0

Sacramento-Del 

Paso Manor

06-067-0006-1 0 0 0 0 0 0 0 0 0 0 0 0

06-067-0006-3 0 0 0 0 0 0 0 0 0 0 0 0

Branch Center 

Road #1b 06-067-0283-1 0 0 0 0 0 0 0 0 NA NA NA NA

Branch Center 

Road #2b 06-067-0284-1 NA NA NA NA NA NA 0 0 0 0 0 0

SacramentoAirport Road

c

06-067-0013-1 0 0 0 0 0 0 0 0 0 0 NA NA

06-067-0013-2 0 0 0 0 0 0 NA NA NA NA NA NA

Sacramento Health 

Dept.-Stockton 

Blvd

06-067-4001-2 0 0 0 0 0 0 0 0 0 0 0 0

06-067-4001-3 0 0 0 0 0 0.3 0.3 0.3 0 0 0 0

SacramentoGoldenland Courtc

06-067-0014-1 NA NA NA NA NA NA NA 0 0 0 0 0

06-067-0014-3 NA NA NA NA NA NA NA NA NA 0 0 0

Sacramento-T 

Street

06-067-0010-1 0 0 0 0 0 0 0 0 0 0 0 0

06-067-0010-2 0 0 0 0 0 NA NA NA NA NA NA NA

06-067-0010-3 0 0 0 0 NA NA NA NA NA NA NA NA

a The data in this table are from AQS QuickLook Reports dated January 10, 2013 and June 7, 2013. 

b The Branch Center Road #1 monitor was replaced by the Branch Center Road #2 monitor, located .25 mi to the 

north, in early 2006.

c

The Airport Road site was relocated to the Goldenland Court site in August 2008.

NA: data are not available.
The EPA Acting Regional Administrator, Alexis Strauss signed the following 

proposed rule on July 12, 2013 and EPA is submitting it for publication in 

the Federal Register (FR). While we have taken steps to ensure the accuracy 

of this Internet version of the proposed rule, it is not the official version 

of the proposal for purposes of public comment. Please refer to the official 

version in a forthcoming FR publication appearing on the Government Printing 

Office’s FDsys website, http://fdsys.gpo.gov/fdsys/search/home.action and on 

Regulation.gov in Docket Number EPA-R09-OAR-2012-0877, 

http://www.regulations.gov

23

B. The Area Must Have a Fully Approved SIP Meeting Requirements 

Applicable for Purposes of Redesignation under Clean Air Act 

Section 110 and Part D.

Section 107(d)(3)(E)(ii) and (v) require EPA to determine 

that the area has a fully approved applicable SIP under section 

110(k) that meets all applicable requirements under section 110 

and part D for the purposes of redesignation. 

1. Basic SIP Requirements under Section 110

The general SIP elements and requirements set forth in 

section 110(a)(2) include, but are not limited to, the 

following: submittal of a SIP that has been adopted by the State 

after reasonable public notice and hearing; provisions for 

establishment and operation of appropriate procedures needed to 

monitor ambient air quality; implementation of a source permit 

program; provision for the implementation of part C requirements 

for prevention of significant deterioration (PSD) provisions; 

provisions for the implementation of part D requirements for 

nonattainment new source review (nonattainment NSR) NSR permit 

programs; provisions for air pollution modeling; and provisions 

for public and local agency participation in planning and 

emission control rule development.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

24

We note that SIPs must be fully approved only with respect 

to applicable requirements for purposes of redesignation in 

accordance with section 107(d)(3)(E)(ii). The section 110 (and 

part D) requirements that are linked to a particular

nonattainment area’s designation and classification are the 

relevant measures to evaluate in reviewing a redesignation 

request. Requirements that apply regardless of the designation 

of any particular area on the State are not applicable 

requirements for the purposes of redesignation, and the State 

will remain subject to these requirements after the Sacramento 

PM10 nonattainment area is redesignated to attainment. 

For example, CAA section 110(a)(2)(D) requires that SIPs 

contain certain measures to prevent sources in a state from 

significantly contributing to air quality problems in another 

state, known as “transport SIPs.” Because the section 

110(a)(2)(D) requirements for transport SIPs are not linked to a 

particular nonattainment area’s designation and classification 

but rather apply regardless of the attainment status, these are 

not applicable requirements for the purposes of redesignation 

under section 107(d)(3)(E). 

Similarly, EPA believes that other section 110 (and part D) 

requirements that are not linked to nonattainment plan 

submissions or to an area’s attainment status are not applicable 

requirements for purposes of redesignation. EPA believes that 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

25

the section 110 (and part D) requirements that relate to a 

particular nonattainment area’s designation and classification 

are the relevant measures to evaluate in reviewing a 

redesignation request. This view is consistent with EPA’s 

existing policy on applicability of the conformity SIP 

requirement for redesignations. See discussion in 75 FR 36023, 

36026 (June 24, 2010).

On numerous occasions, CARB and SMAQMD have submitted and 

we have approved provisions addressing the basic CAA section 110 

provisions. The Sacramento portion of the California SIP13

contains enforceable emission limitations; requires monitoring, 

compiling and analyzing of ambient air quality data; requires 

preconstruction review of new or modified stationary sources; 

provides for adequate funding, staff, and associated resources 

necessary to implement its requirements; and provides the 

necessary assurances that the State maintains responsibility for 

ensuring that the CAA requirements are satisfied in the event 

that Sacramento is unable to meet its CAA obligations. There are 

no outstanding or disapproved applicable SIP submittals with 

respect to the Sacramento portion of the SIP that prevent 

redesignation of the Sacramento PM10 nonattainment area for the 

24-hour PM10 standard. Therefore, we propose to conclude that 

 

13 Sacramento’s portion of the California SIP may be found at

http://yosemite.epa.gov/r9/r9sips.nsf/Casips?readform&count=100&state=Califor

nia.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

26

CARB and SMAQMD have met all SIP requirements for Sacramento 

applicable for purposes of redesignation under section 110 of 

the CAA (General SIP Requirements).

2. SIP Requirements Under Part D

Subparts 1 and 4 of part D, title 1 of the CAA contain air 

quality planning requirements for PM10 nonattainment areas. 

Subpart 1 contains general requirements for all nonattainment 

areas of any pollutant, including PM10, governed by a NAAQS. The 

subpart 1 requirements include, among other things, provisions 

for the reasonable available control measures (RACM), reasonable 

further progress (RFP), emissions inventories, contingency 

measures, and conformity. Subpart 4 contains specific planning 

and scheduling requirements for PM10 nonattainment areas. Section 

189(a), (c), and (e) requirements apply specifically to moderate 

PM10 nonattainment areas and include: (1) an approved permit 

program for construction of new and modified major stationary 

sources; (2) provisions for RACM; (3) an attainment 

demonstration; (4) quantitative milestones demonstrating RFP 

toward attainment by the applicable attainment date; and (5) 

provisions to ensure that the control requirements applicable to 

major stationary sources of PM10 also apply to major stationary 

sources of PM10 precursors except where the Administrator has 

determined that such sources do not contribute significantly to 

PM10 levels that exceed the NAAQS in the area.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

27

As noted above, in 2002, EPA determined that the Sacramento 

PM10 nonattainment area attained the 24-hour PM10 NAAQS based on 

1998-2000 data. (67 FR 7082, February 15, 2002). In accordance 

with EPA’s Clean Data Policy, we have determined that the 

following requirements do not apply to the State for so long as 

Sacramento continues to attain the PM10 standard or until the 

area is redesignated to attainment: an attainment demonstration 

under section 189(a)(1)(B); RACM provisions under sections 

172(c) and 189(a)(1)(C); reasonable further progress provisions 

under section 189(c)(1); and contingency measures under section 

172(c)(9). For other rulemaking actions applying the Clean Data 

Policy in the context of PM10, see 77 FR 31271-72 (proposed 

Determination of Attainment for Paul Spur / Douglas, Arizona); 

76 FR 10821-22 (proposed Determination of Attainment for Truckee 

Meadows, Nevada); 75 FR 13712-14 (proposed Determination of 

Attainment for Coso Junction, California); 75 FR 36027 (proposed 

Redesignation for Coso Junction, California); 73 FR 22313 

(proposed Redesignation for San Joaquin Valley). See also, 40 

CFR 51.918.

Moreover, in the context of evaluating the area’s 

eligibility for redesignation, there is a separate and 

additional justification for finding that requirements 

associated with attainment are not applicable for purposes of

redesignation. Prior to and independently of the Clean Data 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

28

Policy, and specifically in the context of redesignations, EPA 

interpreted attainment-linked requirements as not applicable for 

purposes of redesignation. In the General Preamble, “General 

Preamble for the Interpretation of Title I of the Clean Air Act

Amendments of 1990,” (General Preamble) 57 FR 13498, 13564 

(April 16, 1992), EPA stated: [t]he section 172(c)(9) 

requirements are directed at ensuring RFP and attainment by the 

applicable date. These requirements no longer apply when an area 

has attained the standard and is eligible for redesignation.

Furthermore, section 175A for maintenance plans * * * provides 

specific requirements for contingency measures that effectively

supersede the requirements of section 172(c)(9) for these areas.

See also Calcagni memorandum at 6 (“The requirements for 

reasonable further progress and other measures needed for 

attainment will not apply for redesignations because they only 

have meaning for areas not attaining the standard.”). Thus, even 

if the requirements associated with attainment had not 

previously been suspended, they would not apply for purposes of 

evaluating whether an area that has attained the standard 

qualifies for redesignation. EPA has enunciated this position 

since the General Preamble was published more than twenty years 

ago, and it represents the Agency’s interpretation of what 

constitutes applicable requirements under section 107(d)(3)(E). 

The Courts have recognized the scope of EPA’s authority to 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

29

interpret “applicable requirements” in the redesignation 

context. See Sierra Club v. EPA, 375 F.3d 537 (7th Cir.2004).

The remaining applicable Part D requirements for moderate 

PM10 areas are: (1) an emission inventory under section 172(c)

(3); (2) a permit program for the construction and operation of 

new and modified major stationary sources of PM10 under sections 

172(c)(5) and 189(a)(1)(A); (3) control requirements for major 

stationary sources of PM10 precursors under section 189(e), 

except where the Administrator determines that such sources do 

not contribute significantly to PM10 levels that exceed the 

standard in the area; (4) requirements under section 172(c)(7) 

that meet the applicable provisions of section 110(a)(2); and 

(5) provisions to ensure that federally supported or funded 

projects conform to the air quality planning goals in the 

applicable SIP under section 176(c). We discuss each of these 

requirements below.

 Emissions Inventory

CAA section 172(c)(3) requires states to submit a 

comprehensive, accurate, current inventory of relevant PM10

pollutants for the baseline year from all sources within the 

nonattainment area. The inventory is to address direct and 

secondary PM10 emissions, and all stationary (generally referring 

to larger stationary source or “point” sources), area (generally 

referring to smaller stationary and fugitive sources), and 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

30

mobile (on-road, nonroad, locomotive and aircraft) sources are 

to be included in the inventory. We interpret the Act such that 

the emission inventory requirements of section 172(c)(3) are 

satisfied by the inventory requirements of the maintenance plan. 

See 57 FR 13498, at 13564 (April 16, 1992). Thus, EPA is

proposing to approve the attainment inventories submitted as 

part of the Sacramento PM10 Maintenance Plan as satisfying the 

requirements of sections 172(c)(3) for the purposes of 

redesignation of the Sacramento PM10 nonattainment area to 

attainment for the 24-hour PM10 NAAQS. The attainment inventories 

are described in V.D.1 of this notice.

 Permits for New and Modified Major Stationary Sources

CAA Sections 172(c)(5) and 189(a)(1)(A) require the State 

to submit SIP revisions that establish certain requirements for 

new or modified stationary sources in nonattainment areas, 

including provisions to ensure that major new sources or major 

modifications of existing sources of nonattainment pollutants 

incorporate the highest level of control, referred to as the 

Lowest Achievable Emission Rate (LAER), and that increases in 

emissions from such stationary sources are offset so as to 

provide for reasonable further progress towards attainment in 

the nonattainment area. The process for reviewing permit 

applications and issuing permits for new or modified stationary 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

31

sources in nonattainment areas is referred to as “nonattainment 

New Source Review” (nonattainment NSR). 

EPA has previously approved SMAQMD Rule 203 (Prevention of 

Significant Deterioration) and partially approved and partially 

disapproved SMAQMD Rule 214 (Federal New Source Review). 76 FR 

43183 (July 20, 2011). Because of the partial disapproval, 

SMAQMD does not currently have a fully-approved nonattainment 

NSR program. 

The NSR deficiencies identified in EPA’s partial approval 

and partial disapproval of Rule 214 are limited to the following 

issues: (1) a small number of definitions: “begin actual 

construction,” “federally enforceable,” and “necessary 

preconstruction approvals or permits”; (2) the rule is missing 

adequate public notice requirements for minor sources; (3) the 

rule is missing provisions meeting the requirements of 40 CFR 

51.165(a)(5)(ii) and 40 CFR 51.307(b)(2); and (4) the rule 

contains a cross reference to Rule 207 — Title V — Federal 

Operating Permit Program, which is not SIP approved. The limited 

disapproval triggered an obligation on EPA to promulgate a 

federal implementation plan (FIP) to remedy the NSR deficiencies 

by August 19, 2013. See 77 FR 43184 (July 20, 2011). To correct 

the deficiencies, on September 26, 2012, CARB submitted amended 

SMAQMD Rule 214 for inclusion in the SIP. On February 14, 2013, 

a notice of proposed rulemaking to approve revised Rule 214 was 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

32

published in the Federal Register. See 78 FR 10589. On April 25, 

2013, Regional Administrator Jared Blumenfeld signed a notice of 

final rulemaking to approve revised Rule 214. It is currently 

awaiting publication in the Federal Register. If the final 

rulemaking for revised Rule 214 becomes effective prior to EPA 

finalizing the area’s redesignation to attainment for PM10, the 

172(c)(5) and 189(a(1)(A) requirements would be fulfilled prior 

to redesignation. 

If EPA does not approve revised Rule 214 prior to EPA 

finalizing the area’s redesignation to attainment for PM10, it 

would not affect EPA approval of the redesignation request 

because upon redesignation the requirements of SMAQMD’s PSD 

program would apply to PM10 and PM10 precursor emissions of new 

major sources or major modifications. Thus, new major sources 

with significant PM10 emissions and major modifications of PM10 at 

major sources as defined under 40 CFR 51.21 will be required to 

obtain a PSD permit or include PM10 emissions in their existing 

PSD permit. Since PSD requirements14 will apply after 

redesignation, an area being redesignated to attainment need not 

comply with the requirement that a nonattainment NSR program be 

approved prior to redesignation as long as the state 

demonstrates maintenance of the NAAQS in the area without 

 

14 PSD requirements control the growth of new source emissions in areas 

designated as attainment for a NAAQS.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

33

implementation of nonattainment NSR. A more detailed rationale 

for this view is described in a memorandum from Mary Nichols, 

Assistant Administrator for Air and Radiation, dated October 14, 

1994, titled “Part D New Source Review Requirements for Areas 

Requesting Redesignation to Attainment.” See also, redesignation 

rulemakings for Detroit, Michigan (60 FR 12467-12468, March 7, 

1995); Cleveland-Akron-Lorain, Ohio (61 FR 20458, 20469-20470, 

May 7, 1996); Louisville, Kentucky (66 FR 53665, October 23, 

2001); and, Grand Rapids, Michigan (61 FR 31834-31837, June 21, 

1996). 

Based on our review of the Sacramento PM10 Maintenance Plan, 

we conclude that the maintenance demonstration does not rely on 

implementation of nonattainment NSR because the Plan applies 

standard growth factors to stationary source emissions and does 

not rely on NSR offsets to reduce the rate of increase in 

emissions over time from point sources.15 In addition, the PM10

Maintenance Plan adds emission reduction credits (ERCs) for PM10, 

NOx, and SOx to future projected emissions to ensure that the use 

of ERCs will not be inconsistent with the future PM10 maintenance 

goals. Therefore, EPA concludes that a fully-approved 

nonattainment NSR program is not necessary for approval of the 

State's redesignation request for the Sacramento PM10

nonattainment area.

 

15 See letter, Larry Greene, Executive Officer, SMAQMD, to Deborah Jordan, 

Director, Air Division, US EPA, Region 9, dated June 28, 2013.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

34

We conclude that Sacramento’s portion of the California SIP 

adequately meets the requirements of section 172(c)(5) and 

189(a)(1)(A) for purposes of this redesignation.

 Control Requirements for PM10 Precursors 

Section 189(e) of the CAA requires that the control 

requirements applicable under the part D SIP for major 

stationary sources of PM10 also apply to major stationary sources 

of PM10 precursors, except where the Administrator determines 

that such sources do not contribute significantly to PM10 levels 

which exceed the standard in the area. Sacramento’s PM10

Maintenance Plan states that NOx is a PM10 precursor in the 

secondary formation of atmospheric ammonium nitrates, which are

a significant component of PM10 concentrations in the Sacramento 

area. SMAQMD also determined, based on analyses of inventories16

from CARB and Chemical Mass Balance modeling, that emissions of 

sulfur oxides17 (SOx) and volatile organic compounds (VOCs) from 

sources in the Sacramento nonattainment area are an 

insignificant contributor to secondary particulate formation in 

the Sacramento PM10 nonattainment area. Therefore, SOx and VOC 

emissions are not included in the Sacramento PM10 Maintenance 

 

16 California Emission Forecasting System (CEFS) Version 1.06 Sacramento 

Metropolitan AQMD, Rf#980.

17 The following SMAQMD measures were previously implemented to reduce sulfur 

dioxide emissions: Rule 406 - Specific Contaminants and Rule 420 - Sulfur 

Content of Fuels. These measures were approved into the SIP on December 5, 

1984 (49 FR 47490). Adjusting for the past decrease in SOX emissions, current 

ambient ammonium sulfate concentrations are estimated to be about 1 μg/m3.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

35

Plan. See pages 4-1 and 5-4 in the Sacramento PM10 Maintenance 

Plan. To satisfy ozone nonattainment requirements in CAA section 

182(b), SMAQMD has adopted Reasonably Available Control 

Technology rules to reduce NOX emissions from existing sources. 

See Rules 411, 412, and 413 in Table 3 in this action. These 

rules also address the control requirements in CAA section 

189(e) because they control NOx emissions from major stationary 

sources. Major stationary sources of NOx are also controlled by 

Rules 202 and 203, which are the District’s nonattainment NSR 

and PSD permitting programs. 

 Compliance with Section 110(a)(2)

Section 172(c)(7) requires the SIP to meet the applicable 

provisions of section 110(a)(2). As noted above, we conclude the 

California SIP meets the requirements of section 110(a)(2)

applicable for purposes of this redesignation.

 General and Transportation Conformity Requirements

Under section 176(c) of the Clean Air Act Amendments of 

1990, states are required to establish criteria and procedures 

to ensure that federally supported or funded projects conform to 

the air quality planning goals in the applicable SIP. Section 

176(c) further provides that state conformity provisions must be 

consistent with federal conformity regulations that the CAA 

requires EPA to promulgate. EPA’s conformity regulations are 

codified at 40 CFR part 93, subparts A (referred to herein as 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

36

“transportation conformity”) and B (referred to herein as 

“general conformity”). Transportation conformity applies to 

transportation plans, programs, and projects developed, funded, 

and approved under title 23 U.S.C. or the Federal Transit Act, 

and general conformity applies to all other federally-supported 

or funded projects. SIP revisions intended to address the 

conformity requirements are referred to herein as “conformity 

SIPs.”

EPA believes it is reasonable to interpret the conformity 

SIP requirements as not applying for purposes of a redesignation 

request under section 107(d) because state conformity rules are 

still required after redesignation and federal conformity rules 

apply where state rules have not been approved. See Wall v. EPA,

265 F. 3d 426 (6th Cir. 2001), upholding this interpretation. 

See also, 60 FR 62748 (December 7, 1995).

Thus, EPA proposes to determine that, if EPA later 

finalizes its approval of the Sacramento PM10 Maintenance Plan 

described in today’s proposal and also finalizes its approval of 

the emissions inventory and motor vehicle emissions budgets for 

SMAQMD, the State has a fully-approved SIP meeting all 

requirements applicable under section 110 and part D for the 

Sacramento PM10 nonattainment area for purposes of redesignation. 

CAA Section 107(d)(3)(E)(v).
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

37

C. EPA Has Determined That the Improvement in Air Quality Is Due 

to Permanent and Enforceable Reductions in Emissions.

Section 107(d)(3)(E)(iii) requires EPA to determine that 

the improvement in air quality is due to emission reductions 

that are permanent and enforceable resulting from the 

implementation of the applicable SIP and applicable Federal air 

pollution control regulations and other permanent and 

enforceable regulations in order to approve a redesignation to 

attainment. Under this criterion, the State must be able to 

reasonably attribute the improvement in air quality to emissions 

reductions which are permanent and enforceable. Attainment 

resulting from temporary reductions in emissions rates (e.g., 

reduced production or shutdown due to temporary adverse economic 

conditions) or unusually favorable meteorology would not qualify 

as an air quality improvement due to permanent and enforceable 

emission reductions. Calcagni memorandum, p. 4.

Historically, exceedances of the 24-hour PM10 NAAQS in the 

Sacramento nonattainment area occur in late November and 

December. The Chemical Mass Balance (CMB) model was used to 

identify source contributions for ambient air quality samples 

collected during the winter months (i.e., November through 

January) for 1991-1996. CMB uses known chemical “fingerprints” 

of various source types together with measurements of the 

chemical components of ambient PM10 to find the contribution of 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

38

those sources to PM10 concentrations. CMB results show the main 

components of wintertime PM10 in the Sacramento nonattainment 

area were secondary ammonium nitrate particles (29%), motor 

vehicle exhaust from cars, trucks, and buses (23%), wood smoke 

(17%), and fugitive dust (12%).18 The CMB analysis indicates how 

reductions in emissions of primary PM10 and PM10 precursors (e.g., 

NOx) will reduce ambient PM10 concentrations; each of the ambient 

components can be “rolled back” in proportion to the emission 

changes in the corresponding source categories. The Sacramento 

PM10 Maintenance Plan credits control measures adopted and 

implemented by SMAQMD and CARB and approved into the SIP by EPA 

as reducing emissions to attain the 24-hour PM10 NAAQS. 

The SMAQMD has jurisdiction over air quality planning 

requirements for Sacramento County. The SMAQMD has adopted 

numerous plans, rules, and revisions for Sacramento County in 

order to reduce PM10 and PM10 precursor emissions. The Sacramento 

PM10 Maintenance Plan includes a list of control measures adopted 

and implemented by SMAQMD and approved into the SIP by EPA as 

reducing emissions to attain the 24-hour PM10 NAAQS. Table 3

lists SMAQMD rules contributing towards attainment and/or

continued attainment of the 24-hour PM10 NAAQS. 

 

18 See Sacramento PM10 Maintenance Plan, section 3.5, page 3-10.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

39

Table 3. Sacramento Metropolitan AQMD Control Measures and 

Programs Contributing Towards Attainment and/or Continued 

Attainment of the 24-hour PM10 NAAQS.

Rule Title Date Approved

into SIP Citation

401 Ringelmann Chart/Opacity 02/01/1984 49 FR 3987

403 Fugitive Dust 12/05/1984 49 FR 47490

404 Particulate Matter 07/13/1987 52 FR 26148

405 Dust and Condensed Fumes 12/05/1984 49 FR 47490

406 Specific Contaminants 12/05/1984 49 FR 47490

407 Open Burn 12/05/1984 49 FR 47490

417 Wood Burning Appliances 04/11/2013 78 FR 21540

408 Incinerator Burning 12/05/1984 49 FR 47490

409 Orchard Heaters 12/05/1984 49 FR 47490

411

NOx from Boilers, Process 

Heaters, and Steam

Generators

08/01/2007 72 FR 41894

412

Stationary Source 

Internal Combustion 

Engines at Major 

Stationary Sources of NOx

04/30/1996 61 FR 18959

413 Stationary Gas Turbines 02/11/1999 64 FR 6803

414 Natural Gas Fired Water 

Heaters

04/20/1999, 

11/01/2011

64 FR 19277

76 FR 67366

420 Sulfur Content of Fuels 12/05/1984 49 FR 47490

501 Agricultural Burning 12/05/1984 49 FR 47490

Other SMAQMD measures or programs not in the SIP19,20

 

19 On September 26, 2012, Rule 421 was submitted to EPA for inclusion in the 

SIP. The Wood Stove/Fireplace Change Out Incentive Program, Spare The Air 

public education program, and Sacramento Valley Air Basin Smoke Management 

Program have not been submitted for inclusion in the SIP.

20 Sacramento County also participates in the State’s Sacramento Valley Air 

Basin Smoke Management Program. The program describes the policies and 

procedures used with hourly and daily measurements of air quality and 

meteorology to determine how much open biomass burning can be allowed in the 

Sacramento Valley Air Basin. The program ensures that agricultural burning is 

prohibited on days meteorologically conducive to potentially elevated PM10

concentrations. The area covered by the program is referred to as the 

Sacramento Valley Air Basin, and includes all or parts of the following 

counties: Butte, Colusa, Glenn, Placer (portion), Sacramento, Shasta, Solano 

(portion), Sutter, Tehama, Yolo and Yuba. See Title 17 California Code of 

Regulations, Subchapter 2, Section 80100 et. seq. The regulations can be 

viewed at http://www.arb.ca.gov/smp/regs/RevFinRegwTOC.pdf.
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40

421 Mandatory Episodic Curtailment of Wood and Other Solid 

Fuel Burning

-- Wood Stove/Fireplace Change Out Incentive Program

-- Spare The Air

 

Source categories for which CARB has primary responsibility 

for reducing emissions in California include most new and 

existing on- and off-road engines and vehicles, motor vehicle 

fuels, and consumer products. In addition, California has unique 

authority under CAA section 209 (subject to a waiver by EPA) to 

adopt and implement new emission standards for many categories 

of on-road vehicles and engines, and new and in-use off-road 

vehicles and engines. California has been a leader in the 

development of some of the most stringent control measures 

nationwide for on-road and off-road mobile sources and the fuels 

that power them. These measures have helped reduce primary PM10

and PM10 precursors in the Sacramento PM10 nonattainment area and 

throughout the State.

CARB’s 2007 State Strategy and 2009 and 2011 updates to 

the State Strategy provide a recent summary of the measures 

adopted and implemented by the State.21 From 1994 to 2006, the 

State promulgated more than thirty-five rules that have achieved 

significant emission reductions contributing to attainment and 

continued attainment in the Sacramento PM10 nonattainment area. 

 

21

 See “Air Resources Board’s Proposed State Strategy for California’s 2007 

State Implementation Plan,” release date: April 26, 2007 (2007 State 

Strategy).
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41

See 2007 State Strategy, p.38.

22,23 These measures include new 

emission standards and in-use requirements that have resulted in 

significant reductions in emissions of PM10 and PM10 precursors 

(e.g., NOx) from categories such as passenger cars, trucks, 

buses, motorcycles, locomotives, cargo handling equipment, and 

large off-road equipment. EPA has generally approved into the 

SIP all of the State’s measures that are not subject to the CAA 

section 209 waiver process. See EPA’s final approval of the San 

Joaquin Valley PM2.5 Plan at 76 FR 69896 (November 9, 2011) and

accompanying Technical Support Document and Responses to 

Comments.

24 Finally, in addition to the local district and State 

rules discussed above, the Sacramento PM10 nonattainment area has 

also benefitted from emission reductions from federal measures. 

These federal measures include EPA‘s national emissions 

standards for heavy-duty diesel trucks (66 FR 5001 (January 18, 

 

22 The 2007 Proposed State Strategy can be found at: 

http://arb.ca.gov/planning/sip/2007sip/apr07draft/sipback.pdf. Page 38 of the 

Proposed State Strategy lists forty-five actions; thirty-five of these 

actions provide NOx reductions. 

23 On August 12, 2009, CARB submitted the “Status Report on the State Strategy 

for California’s 2007 State Implementation Plan (SIP) and Proposed Revision 

to the SIP Reflecting Implementation of the 2007 State Strategy,” dated March 

24, 2009 and adopted April 24, 2009 (“2009 State Strategy Status Report”). 

This submittal updated the 2007 State Strategy to reflect its implementation 

during 2007 and 2008. See CARB Resolution No. 09–34, April 24, 2009 and 

letter, James N. Goldstene, Executive Officer, CARB, to Wayne Nastri, 

Regional Administrator, EPA Region 9, August 12, 2009 with enclosures. Only 

pages 11–27 of the 2009 State Strategy Status Report are submitted as a SIP 

revision. The balance of the report is for informational purposes only. See 

Attachment A to CARB Resolution No. 09–34. 

24 Technical Support Document and Responses to Comments, Final Rule on the San 

Joaquin Valley 2008 PM2.5 State Implementation Plan, September 30, 2011. This 

document can be found at: http://www.regulations.gov/#!documentDetail;D=EPAR09-OAR-2010-0516-0175.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

42

2001)), certain emissions standards for new construction and 

farm equipment (Tier 2 and 3 non-road engines standards, 63 FR 

56968 (October 23, 1998) and Tier 4 diesel non-road engine 

standards, 69 FR 38958 (June 29, 2004)), and locomotive engine 

standards (63 FR 18978 (April 16, 1998) and 73 FR 37096 (June 

30, 2008)).

The on-road and off-road vehicle and engine standards cited 

above have contributed to improved air quality through the 

gradual, continued turnover and replacement of older vehicle 

models with newer models manufactured to meet increasingly 

stringent emissions standards. 

We note that many of the control measures cited above and 

in the Sacramento PM10 Maintenance Plan have provided emissions 

reductions since 1990, and thus, the improvement in air quality 

since 1990 may reasonably be attributed to them. 

A sense of the effectiveness of the control measures to 

reduce PM10 and PM10 precursor emissions can be gained by 

comparing emissions in 1990 (a nonattainment year), 2000 (the 

year EPA determined the area met its attainment date) and 2008

(an attainment year).25 In 1990, area-wide PM10 and NOx emissions 

in the Sacramento PM10 nonattainment area were estimated to be 

approximately 37 and 133 tons per day (winter day), 

respectively. In 2000, despite an increase in population and 

 

25 See Appendix A in the Sacramento PM10 Maintenance Plan.
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43

vehicle-miles-traveled (VMT) of approximately 14% and 15%, 

respectively, area-wide emissions of PM10 dropped to 33 tons per 

day and NOx declined to 100 tons per day compared. Despite 

increases between 1990 and 2008 in population (29%) and VMT

(35%), area-wide emissions of direct PM10 decreased slightly to 

35 tons per day. NOx emissions decreased significantly to 82 tons 

per day, a reduction of approximately 38% compared to 1990 

levels.

With respect to the connection between the emissions 

reductions and the improvement in air quality, we also conclude 

that the air quality improvement in the Sacramento PM10

nonattainment area since 1990 through 2011 is not the result of 

a local economic downturn or unusual or extreme weather 

patterns. Our conclusion is based on the air quality data in 

Table 1 and recognition that the fluctuation in economic and 

meteorological conditions since 1998 did not result in a 

violation of the 24-hour PM10 standard.

26 We do recognize that a 

significant economic slowdown occurred nationally starting in 

2008, but we note that the downward PM10 trend had already been 

established before that time (see Figure 3.3 on page 3-7 of the 

Sacramento PM10 Maintenance Plan). 

 

26 EPA’s February 2002 determination that the Sacramento PM10 nonattainment 

area had attained the 24-hour PM10 NAAQS was based on complete, qualityassured, and certified ambient air monitoring data for 1998-2000.
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44

Thus, we find that the improvement in air quality in the 

Sacramento PM10 nonattainment area is the result of permanent and 

enforceable emissions reductions from a combination of EPAapproved local and State control measures and federal control

measures. As such, we propose to find that the criterion for 

redesignation set forth at CAA section 107(d)(3)(E)(iii) is 

satisfied.

D. The Area Must Have a Fully Approved Maintenance Plan under 

Clean Air Act Section 175A.

Section 175A of the CAA sets forth the elements of a 

maintenance plan for areas seeking redesignation from 

nonattainment to attainment. We interpret this section of the 

Act to require, in general, the following core elements: 

attainment inventory, maintenance demonstration plus a 

commitment to submit a second maintenance plan eight years after 

redesignation, monitoring network, verification of continued 

attainment, and contingency plan. See Calcagni memorandum, pages 

8 through 13. 

Under CAA section 175A, a maintenance plan must demonstrate 

continued attainment of the applicable NAAQS for at least ten 

years after EPA approves a redesignation to attainment. Eight 

years after redesignation, the State must submit a revised 

maintenance plan that demonstrates continued attainment for the 

subsequent ten-year period following the initial ten-year 
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45

maintenance period. To address the possibility of future NAAQS 

violations, the maintenance plan must contain such contingency 

provisions that EPA deems necessary to promptly correct any 

violation of the NAAQS that occurs after redesignation of the 

area. Based on our review and evaluation of the plan, as 

detailed below, we are proposing to approve the Sacramento PM10

Maintenance Plan because we believe that it meets the 

requirements of CAA section 175A. 

1. Attainment Inventory

Section 172(c)(3) of the CAA requires plan submittals to 

include a comprehensive, accurate, and current inventory of 

actual emissions from all sources in the nonattainment area. In

demonstrating maintenance in accordance with CAA section 175A 

and the Calcagni memorandum, the State should provide an 

attainment emissions inventory to identify the level of

emissions in the area sufficient to attain the NAAQS. Where the 

State has made an adequate demonstration that air quality has 

improved as a result of the SIP, the attainment inventory will

generally be an inventory of actual emissions at the time the 

area attained the standard. EPA’s primary guidance in evaluating 

these inventories is the document entitled, “PM–10 Emissions

Inventory Requirements,” EPA, OAQPS, EPA–454/R–94–033 (September 

1994) which can be found at: 

http://www.epa.gov/ttn/chief/eidocs/pm10eir.pdf.
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Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

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46

A maintenance plan for the 24-hour PM10 standard must 

include an inventory of emissions of PM10 and its precursors 

(NOx, sulfur oxides, and volatile organic compounds) in the area 

to identify a level of emissions sufficient to attain the 24-

hour PM10 NAAQS. This inventory must be consistent with EPA’s 

most recent guidance on emissions inventories for nonattainment 

areas available at the time and should represent emissions 

during the time period associated with the monitoring data 

showing attainment. The inventory must also be comprehensive, 

including emissions from stationary point sources, area sources, 

and mobile sources. 

SMAQMD selected year 2008 as the year for the attainment 

inventory in the Sacramento PM10 Maintenance Plan. Year 2008 is a 

current, accurate, and comprehensive inventory during a period 

which the area continued to attain the 24-hour PM10 standard 

prior to adoption and submittal of the redesignation request and 

maintenance plan. The attainment inventory will generally be the 

actual inventory during the time period the area attained the 

standard. EPA previously made an attainment determination for 

the Sacramento PM10 nonattainment area. See 67 FR 7082, February 

15, 2002. Thus, Sacramento Metropolitan's selection of 2008 for 

the attainment inventory is acceptable.

Based on our review of the Sacramento PM10 Maintenance Plan, 

we find that the emissions inventories in the Plan are 
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Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

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47

comprehensive in that they include estimates of PM10 and its 

precursors from all of the relevant source categories, which the 

Plan divides among stationary, area wide, on-road motor 

vehicles, and other mobile.

The Sacramento PM10 Maintenance Plan includes inventories 

for total primary PM10 and for NOx as a PM10 precursor. See tables

4-1 and 4-2 in the Sacramento PM10 Maintenance Plan. Appendix A 

to the PM10 Maintenance Plan contains additional details of the 

emission inventories for 2008 (and 1990, 1995, 2000, 2012, and 

2022). As previously described in section V.B.2, SMAQMD 

determined, based on analyses of inventories from CARB and 

Chemical Mass Balance modeling, that emissions of SOx and VOCs 

from sources in the Sacramento nonattainment area are an 

insignificant contributor to secondary particulate formation in 

the Sacramento PM10 nonattainment area. Therefore, SOx and VOC 

emissions are not included in the Sacramento PM10 Maintenance

Plan.

The stationary source category includes non-mobile, fixed 

sources of air pollution. Examples of sources included in this 

category include fuel combustion (e.g., electric utilities), 

waste disposal (e.g., landfills), and oil and gas production. 

SMAQMD’s 2008 (and subsequent year inventories) for stationary 
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48

sources were developed using methods in CARB’s 2009 Almanac27 and 

information reported by emission sources to SMAQMD and entered 

into the California Emission Inventory Development and Reporting 

System (CEIDARS) database.

28 For area wide sources, SMAQMD 

calculated emissions based on reported data for fuel usage, 

product sales, population, employment data, and other parameters 

covering a wide range of activities.29 

The on-road mobile source category consists of trucks, 

automobiles, buses, and motorcycles. The on-road emissions 

inventory estimates in the Sacramento PM10 Plan were prepared by 

CARB using EMFAC2007 (version 2.3), a California model for onroad motor vehicle emissions.30 The vehicle miles traveled were 

developed from Sacramento Area Council of Governments-supplied 

activity data using transportation modeling prepared for the 

Sacramento region’s August 2009 Metropolitan Transportation 

Improvement Program.31

 

27 The 2009 Almanac contains information about current and historical air

quality and emissions in California. In addition, forecasted emissions

are presented. See http://www.arb.ca.gov/aqd/almanac/almanac09/almanac09.htm

28 The CEIDARS database consists of two categories of information: source 

information and utility information. Source information includes the basic 

inventory information generated and collected on all point and area sources. 

Utility information generally includes auxiliary data, which helps categorize 

and further define the source information. Used together, CEIDARS is capable 

of generating complex reports based on a multitude of category and source 

selection criteria.

29 For more information on emissions from the area-wide source category, see 

the CARB web site: http://www.arb.ca.gov/ei/areasrc/areameth.htm.

30 EMFAC software and detailed information on the vehicle emission model can

be found on the CARB web site at http://www.arb.ca.gov/msei/onroad/onroad.htm.

31 Metropolitan Transportation Improvement Program 2009/12, 

Sacramento Area Council of Governments, August 21, 2008.
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Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

49

With respect to nonroad mobile sources (or other mobile as 

categorized in the PM10 Plan), the category includes aircraft, 

trains, boats, and off-road vehicles and equipment used for 

construction, farming, commercial, industrial, and recreational 

activities. CARB used its OFFROAD2007 to calculate the nonroad 

emissions.32 In general, emissions are calculated using equipment 

population, engine size and load, usage activity, and emission 

factors.

Table 4 presents the direct PM10 and PM10 precursor emissions 

(i.e., NOx) estimates contained in the Sacramento PM10

Maintenance Plan for 2008. Based on the estimates in table 4, 

the area-wide category of emissions accounted for 86% of the 

direct PM10, with residential fuel combustion making up 28%, 

construction and demolition 20%, and paved road dust 17% of the 

total direct PM10 inventory for 2008. Mobile source emissions 

accounted for 90% of the NOx emissions generated within the PM10

nonattainment area in 2008 with on-road motor vehicle emissions 

comprising approximately 61% and off-road equipment 20% of the 

total NOx inventory for 2008.

Table 4: 2008 Actual PM10 Emissions from various source 

categories in the Sacramento PM10 Nonattainment Area, Total Daily 

Emissions (tons per day, average winter day)a

Category Emission Source

2008

PM10 NOx

 

32 See http://www.arb.ca.gov/msei/offroad/offroad.htm
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

50

Stationary

Fuel Combustion 0.5 3.9

Industrial 

Processes 1.0 0.1

Area wide

Residential 

Fuel Combustion 9.9 4.4

Farming 

Operations 2.4 -

Construction 

and Demolition 7.0 -

Paved Road Dust 6.1 -

Unpaved Road 

Dust 3.6 -

Managed Burning 

and Disposal - 0.1

Other 1.2 -

On-Road Motor 

Vehicles

On-Road Motor 

Vehicles 2.2 49.6

Other Mobile

Aircraft 0.1 2.0

Trains 0.1 3.4

Boats 0.1 0.5

Equipment 

(Off-Road/Farm)

1.1 17.8

Totals 35 82

a From Appendix A in the Sacramento PM10 Maintenance Plan.

Based on our review of the emissions inventories (and 

related documentation) from the Sacramento PM10 Maintenance Plan, 

we find that the inventories for 2008 are comprehensive, that 

the methods and assumptions used by CARB and SMAQMD to develop 

the emission inventories are reasonable, and that the 2008 

inventory reasonably estimates actual PM10 emissions in the 
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Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

51

attainment year. Therefore, we are proposing to approve the 2008

inventory, which serves as the Sacramento PM10 Maintenance Plan’s

attainment year inventory, as satisfying the requirements of 

section 172(c)(3) of the CAA for the purposes of redesignation 

of the Sacramento PM10 nonattainment area to attainment of the 

24-hour PM10 NAAQS.

2. Maintenance Demonstration

Section 175A(a) of the CAA requires that the maintenance 

plan “provide for the maintenance of the national primary 

ambient air quality standard for such air pollutant in the area 

concerned for at least 10 years after the redesignation.” 

Generally, a state may demonstrate maintenance of the 24-hour 

PM10 NAAQS by modeling to show that the future mix of sources and 

emissions rates will not cause a violation of the NAAQS. A 

showing that future emissions will not exceed the level of the 

attainment year inventory can also be used to further support of 

a maintenance demonstration. For areas that are required under 

the Act to submit modeled attainment demonstrations, the 

maintenance demonstration should use the same type of modeling. 

Calcagni memorandum, page 9.

In addition to accounting for area-wide growth trends, 

SMAQMD included growth in airport emissions to accommodate 

future airport expansions within the Sacramento County Airport 
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52

System.

33 The portion of the 2012 and 2022 inventories associated 

with airports is detailed in table 5.

Table 5. Airport Emissions for Sacramento County Only, Total 

Daily Emissions (tons per day, average winter day)a

Emission Source

NOx PM10

2012 2022 2012 2022

Aircraft Operations Only 2.3 3.0 0.1 0.1

Ground Support Equipment 0.3 0.2 0.1 0.1

a From table 4-4 in the Sacramento PM10 Maintenance Plan.

SMAQMD also included emissions reduction credits (ERCs) 

from pre-2008 ERCs, future bankable rice burning ERCs, and the 

wood stove/fireplace change out incentive program in the event 

that the ERCs are used for the purposes of issuing permits for 

new or modified stationary sources in the air quality planning 

area.

34

We have reviewed the methods and assumptions, as described 

in connection with the attainment inventory, that SMAQMD used to 

project emissions to 2012 and 2022 for the various source 

categories and find them to be reasonable. The Sacramento PM10

Maintenance Plan’s maintenance demonstration is based on the use 

of Chemical Mass Balance (CMB) with proportional rollback (69 FR 

5412, 5424–5425 and 69 FR 30006) to demonstrate maintenance of 

the 24-hour PM10 standard until 2022. See Plan, pp. 6–1 – 6-5.

Under proportional rollback, changes in source categories’ 

 

33 See Sacramento PM10 Maintenance Plan, section 4.7, page 4-10.

34 See Sacramento PM10 Maintenance Plan, section 4.7, page 4-11.
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53

emissions are added in proportion to their corresponding 

component from CMB. In proportional rollback, a 1% change in 

direct PM10 emissions causes a 1% change in the direct PM10

ambient component. However, because ammonium nitrate is 

secondary PM, that is, it is formed from chemical reactions in 

the air, it does not necessarily scale one-to-one with the 

precursor NOx emissions. The Plan relied on photochemical 

modeling results showing that a 1% change in NOx emission causes 

only a 0.7% change in ammonium nitrate. See Plan, p.6-3.

The results of the modeling show that all monitoring sites 

in the Sacramento PM10 nonattainment area will be below the 24-

hour PM10 NAAQS in 2022, with the projected value of 99 μg/m3 at

the T Street site, which had the peak monitored value from 2006-

2008 in the Sacramento PM10 nonattainment area. See Plan, Table 

6.3.

In addition to the CMB rollback modeling in the Sacramento 

PM10 Maintenance Plan, it also demonstrates that the 2022 

maintenance year inventory is well below the 2008 attainment 

year inventory for PM10 precursors (i.e., NOX) and flat for 

direct PM10. Thus, even without the rollback analysis previously 

described, the Plan clearly demonstrates maintenance of the PM10

NAAQS through 2022. Tables 6, 7 and 8 compare inventory 

estimates for direct PM10 and PM10 precursor (i.e., NOx) for 

various years, including the 2008 attainment year, 2012, and the 
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54

2022 maintenance year. Since current ambient concentrations are 

well below the NAAQS, the slight increase in projected direct 

PM10 emissions is consistent with maintenance of the NAAQS. Even 

if all ambient PM10 were directly emitted (i.e., without 

accounting for the benefit of NOx reductions), the 2008 measured 

ambient level of 109 μg/m3 could increase by 37% and remain below 

the NAAQS, so direct PM10 emissions could also increase by 37% 

and the area would remain in attainment. In fact, direct PM10 is 

projected to increase by only 3% (or 7% considering potential 

increases in road dust allowed for in the Motor Vehicle 

Emissions Budget). This is a very conservative conclusion, 

because is assumes NOx emissions are constant, whereas they are 

actually projected to decrease by 50%, with an accompanying 

reduction in the ammonium nitrate component of PM10. The effects 

of the declining NOx and slightly increasing PM constitute a 

variant of simple rollback modeling, and can be considered a 

second, supporting maintenance demonstration method in addition 

to the CMB proportional rollback demonstration.

Table 6: Summary of 2008 Actual and 2012 and 2022 Projected PM10

and NOx Emissions in the Sacramento PM10 Nonattainment Area (tons 

per day, average winter day)a

Pollutants 2008 2012 2022

PM10 35 35 36

NOx 82 67 42

a From Appendix A in the Sacramento PM10 Maintenance Plan; 

includes Emission Reduction Credits in 2012 and 2022 for PM10 and 

NOx in table 4-5 of the Sacramento PM10 Maintenance Plan.
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the accuracy of this version, but it is not the official version.

55

Based on our review of the 2012 and 2022 emissions 

inventories and related documentation from the Sacramento PM10

Maintenance Plan, we find that the 2012 and 2022 emissions 

inventories in the PM10 Maintenance Plan reflect the latest 

planning assumptions and emissions models available at the time 

the Plan was developed, and provide a comprehensive and 

reasonably accurate basis upon which to forecast direct PM10 and 

PM10 precursor emissions for years 2012 and 2022.35 These 

inventories further support maintenance through 2022.

Table 7: 2008 Actual and 2012 and 2022 Projected PM10 Emissions 

from various source categories in the Sacramento PM10

Nonattainment Area, Total Daily Emissions (tons per day, average 

winter day)a

Category Emission Source

PM10

2008 2012 2022

Stationary

Fuel Combustion 0.5 0.5 0.6

Industrial 

Processes 1.0 0.9 1.1

Area wide

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

 

35 The 2022 emission inventory includes emissions reductions from State 

measures adopted through 2006. Because the measures in Table 3 were adopted 

after 2006, the 2022 inventory is a conservative estimate of the projected 

emissions. December 27, 2012 email from Martin Johnson of CARB to John 

Ungvarsky, EPA. 
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Other 1.2 1.3 1.4

On-Road Motor 

Vehicles

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

Totals 35 35 36

a From Appendix A in the Sacramento PM10 Maintenance Plan.

Table 8: 2008 and Projected 2012 and 2022 NOx Emissions from 

various source categories in the Sacramento PM10 Nonattainment 

Area, Total Daily Emissions (tons per day, average winter day)a

Category Emission Source

NOx

2008 2012 2022

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

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
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Farm Equipment 1.8 1.4 0.6

Totals 82 67 42

a From Appendix A in the Sacramento PM10 Maintenance Plan.

Taking the CMB results into account gives an even stronger 

conclusion with respect to the acceptability of the slight 

increase of direct PM10 emissions. According to the CMB 

proportional rollback, direct PM10 contributes 81 μg/m3 of the

2008 total. See Plan, Table 6.3, p.6-5. Considering the measured 

109 μg/m3, that component could increase by 41 μg/m3, or 50%, and 

the sum would remain below the NAAQS. When combined, the 

projected slight PM10 emissions increase and substantial NOx

emissions decrease are well below the levels consistent with 

attainment through the 2022 maintenance period and thereby 

adequately demonstrate maintenance through that period.

a. Showing That Maintenance Plan Provides for Ten Years of 

Maintenance Through 2023

Section 175A requires a state seeking redesignation to

attainment to submit a SIP revision to provide for the 

maintenance of the NAAQS in the area “for at least 10 years 

after the redesignation.” EPA has interpreted this as a showing 

of maintenance “for a period of ten years following 

redesignation.” September 4, 1992 Memorandum from John Calcagni, 
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the accuracy of this version, but it is not the official version.

58

Director, AQMD, “Procedures for Processing Requests to 

Redesignate Areas to Attainment,” p. 9. 

As discussed in detail above, the Sacramento PM10

Maintenance Plan expressly documents that the area’s emissions 

inventories will remain below the attainment year inventories 

through 2022. In addition, for the reasons set forth below, EPA 

believes that the State’s submission, in conjunction with 

additional supporting information, further demonstrates that the 

area will continue to maintain the 24-hour PM10 NAAQS at least 

through 2023. Thus, if EPA finalizes its proposed approval of 

the redesignation request and maintenance plans in 2013, it will 

be based in part on a showing, in accordance with section 175A, 

that the Sacramento PM10 Maintenance Plan provides for 

maintenance for at least ten years after redesignation. EPA 

believes the area will continue to maintain the 24-hour PM10

NAAQS at least through 2023 for the following reasons.

1. Significant emissions controls remain in place and will 

continue to provide reductions that keep the area in 

attainment. Because the Sacramento area is currently 

nonattainment for the 1997 and 2008 ozone standards and the

2006 24-hour PM2.5 standard, it is expected that not only 

will existing emissions controls remain in place, but the 

Sacramento area may need additional reductions (e.g., NOx)

to attain the aforementioned standards. In addition, the 
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the accuracy of this version, but it is not the official version.

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emissions controls that brought the area into attainment 

cannot be removed from the SIP unless the State 

demonstrates that the removal would be consistent with 

sections 110(l) and 193 of the CAA.

2. The 2022 projected emissions inventory for PM10 precursors 

is well below the 2008 attainment year level and is

expected to decline or remain stable during the 2022 to 

2023 period. It is extremely improbable that emissions 

would increase between 2022 and 2023 such that they would 

exceed the 2008 attainment year levels. As shown in table

7, while primary PM10 emissions have remained relatively 

flat, by 2022 NOx emissions are projected to decline by 

approximately 70% and 49% when compared to 1990 and 2008, 

respectively. The majority of these reductions resulted 

from cleaner fuels, tighter emission standards, and fleet 

turnover in the mobile source sector. The 2022 emission 

inventory is conservative in that it does not include 

reductions from State measures adopted after 2006. Because 

Sacramento is nonattainment for the 1997 and 2008 ozone 

standards and the 2006 24-hour PM2.5 standard, SMAQMD and

the State may need to adopt additional measures that will 

further reduce emissions between 2013 and 2023. Because 

fundamental relaxations or changes to the existing SIPapproved measures, mobile source fleet, and infrastructure
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cannot be easily made or reversed during the 2022-2023 

period, it is highly unlikely that PM10 and PM10 precursor

emissions would increase significantly between 2022 and 

2023 to the extent it would jeopardize a showing of 

maintenance for a 10-year period after redesignation.

3. Fleet turnover supports a continued gradual decrease in 

emission levels beyond 2025. Specifically, California's Low 

Emission Vehicle (LEV) program sets gasoline and vehicle 

emissions standards for passenger cars, light trucks, and 

larger passenger vehicles. The program was designed to 

reduce emissions, including NOx, responsible for the ozone 

and particulate matter impacts from these vehicles. The LEV 

2 standards were phased in between 2004 and 2010, have been 

replaced by the LEV 3 standards adopted in 2012. The LEV 3 

standards represent a further strengthening of the program 

and are planned to be phased in between 2015 and 2025. 

Consequently, the full emission reduction benefits from the 

LEV 2 and 3 standards will not be achieved until after 2022 

and continue beyond 2023.36 The relationship between the LEV 

standards and fleet turnover is just one example of a 

 

36 2011 records from CARB’s inspection and maintenance program indicate 

approximately 20% of the fleet had not yet turned over after 15 years. It is 

reasonable to assume that because the LEV 2 standards were not fully 

implemented until 2009, the reductions from the program will continue through 

2023, which would represents the 14 years of turnover affected by the LEV 2

standards. Thus, it is reasonable to conclude reductions from fleet turnover 

would continue even beyond 2023. To see the report, go to: 

http://www.bar.ca.gov/80_BARResources/04_Miscellaneous/USEPA%202010%20Calenda

r%20Year.pdf.
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measure providing continued NOx emissions reductions between 

2022 and 2023 because of continued fleet turnover.

4. Air quality concentrations are well below the 24-hour PM10

NAAQS, and, when coupled with the emissions inventory 

projections through 2022, clearly show it would be very 

unlikely for a PM10 violation to occur in 2023. The 

Sacramento PM10 nonattainment area has not violated the 24-

hour PM10 NAAQS since 1990. Air quality concentrations for

the three most recent years (2009–2011) of complete, 

quality-assured, and certified ambient air monitoring data 

show the highest monitored PM10 concentration to be 76 

μg/m3, approximately half of the PM10 NAAQS. The historical 

trend of the maximum 24-hour PM10 peak concentrations 

between 1989 and 2011 indicates a steady decline.37 As shown 

in table 7, by 2022 PM10 precursor emissions (NOx) will drop 

significantly compared to 2008, and direct PM10 emissions 

will remain relatively flat. The combination of the air 

quality concentrations well below the standard and the 

declining inventory as described above indicate it is 

highly unlikely that the Sacramento PM10 nonattainment area 

will violate the 24-hour PM10 NAAQS during the 2022 to 2023 

period. 

 

37 See Sacramento PM10 Maintenance Plan, Figure 3.3, page 3-7.
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For the above reasons, EPA believes the area will continue 

to maintain the 24-hour PM10 NAAQS at least through 2023 and 

that the Sacramento PM10 Maintenance Plan shows maintenance for a 

period of ten years following redesignation. Thus, if EPA 

finalizes its proposed approval of the Sacramento PM10

Maintenance Plan in 2013, it is based on a showing, in 

accordance with section 175A, that the Sacramento PM10

Maintenance Plan provides for maintenance for at least ten years 

after redesignation.

3. Verification of Continued Attainment

In demonstrating maintenance, continued attainment of the 

NAAQS can be verified through operation of an appropriate air 

quality monitoring network. The Calcagni memorandum states that 

the maintenance plan should contain provisions for continued 

operation of air quality monitors that will provide such 

verification. Calcagni memorandum, p. 11. As discussed in 

section V.A. of this document, PM10 is currently monitored by 

SMAQMD (five sites) and CARB (one site) within the Sacramento 

PM10 nonattainment area. In the Sacramento PM10 Maintenance Plan 

(see Plan, p. 7-1), SMAQMD indicates its intention to continue 

operation of an air quality monitoring network that meets or 

exceeds the minimum monitoring requirements and that ambient PM10

concentrations will be monitored appropriately to verify 

continued attainment of the 24-hour PM10 NAAQS. The Sacramento 
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Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

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PM10 Maintenance Plan also notes that a review of the entire 

monitoring network will be undertaken annually as required by 

federal regulations.38 We find the SMAQMD’s commitment for 

continued ambient PM10 monitoring as set forth in the Sacramento 

PM10 Maintenance Plan to be acceptable.

Second, the transportation conformity process, which would 

require a comparison of on-road motor vehicle emissions that 

would occur under new or amended regional transportation plans 

and programs with the MVEBs in the PM10 Maintenance Plan, 

represents another means by which to verify continued attainment 

of the 24-hour PM10 NAAQS in Sacramento County. See page 8-1 of 

the Sacramento PM10 Maintenance Plan. 

Lastly, while not cited in the Plan, CARB and SMAQMD must 

inventory emissions sources and report to EPA on a periodic 

basis under 40 CFR part 51, subpart A ("Air Emissions Reporting 

Requirements"). These emissions inventory updates will provide a 

third way to evaluate emissions trends in the area and thereby 

verify continued attainment of the NAAQS. These methods are 

sufficient for the purpose of verifying continued attainment.

4. Contingency Provisions

Section 175A(d) of the Clean Air Act requires that 

maintenance plans include contingency provisions, as EPA deems 

necessary, to promptly correct any violations of the NAAQS that 

 

38 EPA's requirements for annual review of monitoring networks are found at 

40 CFR 58.10.
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occur after redesignation of the area. Such provisions must 

include a requirement that the State will implement all measures 

with respect to the control of the air pollutant concerned that 

were contained in the SIP for the area before redesignation of 

the area as an attainment area. These contingency provisions are 

distinguished from those generally required for nonattainment 

areas under section 172(c)(9) in that they are not required to 

be fully-adopted measures that will take effect without further 

action by the state in order for the maintenance plan to be 

approved. However, the contingency plan is considered to be an 

enforceable part of the SIP and should ensure that the 

contingency measures are adopted expeditiously once they are 

triggered by a specified event.

Under section 175A(d), contingency measures identified in 

the contingency plan do not have to be fully adopted at the time 

of redesignation. However, the contingency plan is considered to 

be an enforceable part of the SIP and should ensure that the 

contingency measures are adopted expeditiously once they are 

triggered by a specified event. The maintenance plan should 

clearly identify the measures to be adopted, a schedule and 

procedure for adoption and implementation, and a specific 

timeline for action by the State. As a necessary part of the 

plan, the State should also identify specific indicators or 
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triggers, which will be used to determine when the contingency 

measures need to be implemented.

As required by section 175A of the CAA, SMAQMD has adopted 

a contingency plan to address possible future PM10 air quality 

problems. The contingency provisions in the Sacramento PM10

Maintenance Plan are contained in section 7.3 of the Plan and 

were clarified in a subsequent letter from the District.39 After 

verification of the 24-hour PM10 NAAQS violation, including 

allowing sufficient time for sample weighing and processing, 

SMAQMD commits to the following steps. 

(1) Examine the violation to determine if it qualifies as a 

natural or exceptional event. 

(2) If the violation was not a natural or exceptional 

event, SMAQMD will analyze the event to determine its plausible 

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 SMAQMD PM2.5 and NOX measures to 

address ozone and PM2.5 SIP requirements. In addition, the SMAQMD

would evaluate applicable reasonably available control measures 

 

39 See letter, Larry Greene, Executive Officer, SMAQMD, to Deborah Jordan, 

Director, Air Division, US EPA, Region 9, dated June 28, 2013. 
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(RACM) that could potentially provide the corrective action 

needed. This evaluation step will take no more than 18 months.

(3) 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. 

Appendix B in the Sacramento PM10 Maintenance Plan contains 

potential RACM measures to be evaluated for future adoption and 

implementation. This adoption and implementation step will take 

no more than 12 months.

In their June 28, 2013 letter, SMAQMD clarified that all 

three of the aforementioned steps will be completed, including 

the implementation of additional control measures, within 24

months. 

Upon our review of the Plan, as summarized above, we find 

that the contingency provisions of the Sacramento PM10

Maintenance Plan clearly identify specific contingency measures, 

contain tracking and triggering mechanisms to determine when 

contingency measures are needed, contain a description of the 

process of recommending and implementing contingency measures, 

and contain specific timelines for action. Thus, we conclude 

that the contingency provisions of the Sacramento PM10

Maintenance Plan are adequate to ensure prompt correction of a 

violation and therefore comply with section 175A(d) of the Act.
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For the reasons set forth above, EPA is proposing to find that 

the Sacramento PM10 Maintenance Plan is consistent with the 

maintenance plan contingency provision requirements of the CAA

and EPA guidance.

5. Subsequent Maintenance Plan Revisions

Section 175A(b) of the CAA provides that eight years after 

redesignation, the State must submit a revised maintenance plan 

that demonstrates continued attainment for the subsequent tenyear period following the initial ten-year maintenance period.

The Sacramento PM10 Maintenance Plan includes a SMAQMD commitment

to prepare and submit a revised maintenance plan in 2020, seven 

years after redesignation to attainment. See page 6-7 of the 

Sacramento PM10 Maintenance Plan.

In light of the discussion set forth above, EPA is 

proposing to approve the Sacramento PM10 Maintenance Plan as 

meeting the requirements of CAA section 175A.

6. Transportation Conformity and Motor Vehicle Emissions Budgets

a. Requirements for Transportation Conformity and Motor Vehicle 

Emissions Budgets

Under section 176(c) of the CAA, transportation plans, 

programs and projects in the nonattainment or maintenance areas 

that are funded or approved under title 23 U.S.C. and the

Federal Transit Laws (49 U.S.C. chapter 53) must conform to the 

applicable SIP. In short, a transportation plan and program are 
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deemed to conform to the applicable SIP if the emissions 

resulting from the implementation of that transportation plan 

and program are less than or equal to the motor vehicle 

emissions budgets (budgets) established in the SIP for the 

attainment year, maintenance year and other years. See, 

generally, 40 CFR part 93 for the federal conformity regulations 

and 40 CFR 93.118 specifically for how budgets are used in 

conformity.

The budgets serve as a ceiling on emissions that would 

result from an area's planned transportation system. The budget

concept is further explained in the preamble to the November 24, 

1993, transportation conformity rule (58 FR 62188). Maintenance 

plan submittals must specify the maximum emissions of 

transportation-related PM10 and NOx emissions allowed in the last 

year of the maintenance period, i.e., the motor vehicle 

emissions budgets (MVEBs). (MVEBs may also be specified for 

additional years during the maintenance period.) The submittal 

must also demonstrate that these emissions levels, when 

considered with emissions from all other sources, are consistent 

with maintenance of the NAAQS.

b. Motor Vehicle Emissions Budgets in the Sacramento PM10

Maintenance Plan

The Sacramento PM10 Maintenance Plan contains PM10 and NOx

MVEBs for the Sacramento PM10 nonattainment area for 2008, 2012, 
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and 2022. The MVEBs are the on-road mobile source primary PM10

and NOx (as a PM10 precursor) emissions for Sacramento County for 

2008, 2012 and 2022. The MVEBs are compatible with the 2008, 

2012, and 2022 on-road mobile source PM10 and NOx emissions 

included in SMAQMD’s 2008, 2012, and 2022 PM10 and NOx emission 

inventories, as summarized above in tables 6, 7 and 8. The 

derivation of the MVEBs is thoroughly discussed in section 8 of 

the Sacramento PM10 Maintenance Plan.

40 The motor vehicle 

emissions budgets for Sacramento are summarized in table 9. 

Table 9: Summary of Motor Vehicle Emissions Budgets (tons per 

day, average winter day) in the Sacramento PM10 Maintenance Plan41

Budget Year PM10 NOx

2008 15 50

2012 15 38

2022 17 19

The details for each component of the budgets are shown in 

table 10 and are comprised of direct on-road mobile source 

emissions, road construction emissions, fugitive emissions from 

paved and unpaved roads, and safety margins. A state may choose 

to apply a safety margin under our transportation conformity 

rule so long as such margins are explicitly quantified in the 

applicable plan and are shown to be consistent with attainment 

or maintenance of the NAAQS (whichever is relevant to the 

 

40 Additional information associated with the motor vehicle emission budget 

calculations is provided in a technical analysis accompanying June 2013 

letters from ARB and SMAQMD to EPA.

41 See Table 8.1, page 8-4 of the Sacramento PM10 Maintenance Plan.
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particular plan).42 In this instance, the safety margin has been 

explicitly quantified and shown to be consistent with continued 

maintenance of the PM10 NAAQS through the applicable maintenance 

period, through 2023. The MVEBs incorporate: (1) on-road motor 

vehicle emission inventory factors of EMFAC200743 and AP-42;44 and 

(2) updated recent vehicle activity data from Sacramento Area 

Council of Governments’ Sacramento Activity-Based Travel Demand 

Simulation Model transportation modeling system.

Table 10: Source Categories and Emissions Comprising the Motor 

Vehicle Emissions Budgets (tons per day, average winter day) in

the Sacramento PM10 Maintenance Plan45

Category 2008 2012 2022

NOx PM10 NOx PM10 NOx PM10

Direct Exhausta 49.6 2.2 37.6 2.1 18.1 2.1

Paved Road Dust -- 6.1 -- 4.9 -- 5.5

Unpaved Road Dust -- 3.6 -- 3.6 -- 3.6

Road Construction 

Dust -- 2.7 -- 2.8 -- 2.8

Safety Margin46 -- -- -- 1.3 -- 2.5

 

42 See 40 CFR 93.124(a).

43 EMFAC (EMission FACtor) is California’s model for estimating emissions from 

on-road vehicles operating in California. EPA approved EMFAC2007 on January 

18, 2008 (73 FR 3464). CARB’s latest release is EMFAC 2011 which EPA approved 

on March 6, 2013 (78 FR 14533) was not approved when this plan was developed.

44 AP-42, Compilation of Air Pollutant Emission Factors, is a document 

published by EPA as the primary collection of EPA approved emission factor 

information. The emission factors have been developed and compiled from 

source test data, material balance studies, and engineering estimates. EPA 

has publishes supplements and updates to the each of the chapters available 

in Volume I, Stationary Point and Area Sources at the following web site:

http://www.epa.gov/ttnchie1/ap42/.

45 Ibid.

46 The Sacramento PM10 Maintenance Plan includes PM10 MVEB safety margins of 1.3 

tons per day (tpd) for 2012 and 2.4 tpd for 2022. This additional increase 

may be needed for the Sacramento Area Council of Governments to make a 

transportation conformity determinations, including 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 Sacramento PM10 Maintenance 

Plan. See letter, Larry Greene, Executive Officer, SMAQMD, to Deborah Jordan, 

Director, Air Division, US EPA, Region 9, dated June 28, 2013. Also see 
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Totals (rounded 

up to nearest 

ton)

50 15 38 15 19 17

a Direct Exhaust includes PM10 from tire and brake wear.

c. Initial Adequacy Review of Budgets

On September 1, 2011, EPA announced the availability of the 

Sacramento PM10 Maintenance Plan with MVEBs and a 30-day public 

comment period on EPA's Adequacy Web site at: 

http://www.epa.gov/otaq/stateresources/transconf/reg9sips.htm#ca

. The comment period for this notification ended on October 3, 

2011, and EPA received no comments from the public. On November 

23, 2011, EPA published in the Federal Register (76 FR 72404) a 

finding of adequacy for the PM10 MVEBs for the years 2008, 2012, 

and 2022.

d. Updated Technical Review

As described earlier, the budgets were developed using 

emission factors generated by CARB’s EMFAC2007 model and AP-42. 

The paved road emissions were originally calculated using the 

2006 version of AP-42 by estimating the 2008 paved road 

emissions and projecting them to 2012 and 2022. The calculation 

relied on a California profile of silt loading, weather, and 

growth in roadway centerline miles. 

EPA released an update to Compilation of Air Pollutant 

Emission Factors (AP-42) in January of 2011, which revised the 

 

letter, Lynn Terry, Deputy Executive Officer, CARB, to Deborah Jordan, 

Director, Air Division, US EPA, Region 9, dated June 13, 2013.
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equation for estimating paved road dust emissions based on an 

updated regression that included new emission tests results. 

CARB staff conducted an additional technical analysis of the 

Sacramento County paved road emission projections using the 

updated AP-42 equation and growth in vehicle miles traveled, to 

ensure that the motor vehicle emission budgets were still 

consistent with the currently approved modeling tools and data 

and the maintenance demonstration. The technical analysis showed 

that the updated paved road emissions provided safety margins in 

2012 and 2022 as compared to the attainment inventory emissions 

of paved road dust which was used in establishing the MVEBs in 

the Sacramento PM10 Maintenance Plan.

47 Therefore, the total MVEBs 

are consistent with maintenance of the standard.

e. Proposed Actions on the Budgets

EPA is proposing to approve the MVEBs for 2008, 2012 and 

2022 as part of our approval of Sacramento PM10 Maintenance Plan.

EPA has determined that the MVEB emission targets are consistent 

with emission control measures in the SIP and that Sacramento 

County can maintain attainment of the 24-hour PM10 NAAQS. Because 

the budgets EPA found adequate in 2011 are the same budgets EPA 

is proposing to approve in this action, if EPA approves the 

MVEBs in the final rulemaking action, it would not change the 

 

47 See letter, Lynn Terry, Deputy Executive Officer, CARB, to Deborah Jordan, 

Director, Air Division, US EPA, Region 9, dated June 13, 2013. See Letter, 

Larry Greene, Executive Director/Air Pollution Control Officer, SMAQMD, to 

Deborah Jordan, Director Air Division, US EPA, Region 9, dated June 28, 2013.
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budgets currently in use for future transportation conformity 

determinations for Sacramento County. As discussed in section 

V.D.2.a of this notice, EPA is proposing that if this approval 

is finalized in 2013 the area will continue to maintain the 24-

hour PM10 NAAQS through at least 2023. Consistent with this 

proposal, EPA is proposing to approve the MVEBs submitted by the 

State in the Sacramento PM10 Maintenance Plan. EPA is proposing 

that the submitted budgets, when combined with EPA’s additional 

analysis for the 2022–2023 time period, are consistent with 

maintenance of the 24-hour PM10 NAAQS through 2023.

VI. Proposed Action and Request for Public Comment

Based on our review of the Sacramento PM10 Maintenance Plan 

submitted by the State, air quality monitoring data, and other 

relevant materials, EPA is proposing to find that the State has 

addressed all the necessary requirements for redesignation of 

the Sacramento nonattainment area to attainment of the PM10

NAAQS, pursuant to CAA sections 107(d)(3)(E) and 175A. 

First, under CAA section 107(d)(3)(D), we are proposing to 

approve CARB’s request, which accompanied the submittal of the 

Sacramento PM10 Maintenance Plan, to redesignate the Sacramento 

PM10 nonattainment area to attainment for the 24-hour PM10 NAAQS. 

We are doing so based on our conclusion that the area has met 

the five criteria for redesignation under CAA section 

107(d)(3)(E). Our conclusion is based on our proposed 
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determination that the area has attained the 24-hour PM10 NAAQS; 

that relevant portions of the California SIP are fully approved; 

that the improvement in air quality is due to permanent and 

enforceable reductions in emissions; that California has met all 

requirements applicable to the Sacramento PM10 nonattainment area 

with respect to section 110 and part D of the CAA; and is based 

on our proposed approval of the Sacramento PM10 Maintenance Plan

as part of this action.

Second, in connection with the Sacramento PM10 Maintenance 

Plan and EPA’s analysis showing maintenance through 2023, EPA 

finds that the maintenance demonstration showing how the area 

will continue to attain the 24-hour PM10 NAAQS for 10 years 

beyond redesignation (i.e., through 2023) and the contingency 

provisions describing the actions that SMAQMD will take in the 

event of a future monitored violation meet all applicable 

requirements for maintenance plans and related contingency 

provisions in section 175A of the CAA. EPA is also proposing to 

approve the motor vehicle emissions budgets in the Sacramento 

PM10 Maintenance Plan because we find they meet the applicable 

transportation conformity requirements under 40 CFR 93.118(e).

Lastly, EPA is proposing to approve the 2008 inventory, which 

serves as the Sacramento PM10 Maintenance Plan’s attainment year 

inventory, as satisfying the requirements of section 172(c)(3)

of the CAA.
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We are soliciting comments on these proposed actions. We 

will accept comments from the public on this proposal for 30 

days following publication of this proposal in the Federal

Register. We will consider these comments before taking final 

action.

VII. Statutory and Executive Order Reviews

Under the CAA, redesignation of an area to attainment and 

the accompanying approval of a maintenance plan under section 

107(d)(3)(E) are actions that affect the status of a 

geographical area and do not impose any additional regulatory 

requirements on sources beyond those imposed by State law. 

Redesignation to attainment does not in and of itself create any 

new requirements, but rather results in the applicability of 

requirements contained in the CAA for areas that have been 

redesignated to attainment. Moreover, the Administrator is 

required to approve a SIP submission that complies with the 

provisions of the Act and applicable federal regulations. 42 

U.S.C. 7410(k); 40 CFR 52.02(a). Thus, in reviewing SIP 

submissions, EPA's role is to approve State choices, provided 

that they meet the criteria of the Clean Air Act. Accordingly, 

these actions merely propose to approve a State plan and 

redesignation request as meeting federal requirements and do not 

impose additional requirements beyond those by State law. For 

these reasons, these proposed actions:
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the accuracy of this version, but it is not the official version.

76

 Are not a "significant regulatory action” subject to review 

by the Office of Management and Budget under Executive 

Order 12866 (58 FR 51735, October 4, 1993); 

 Do not impose an information collection burden under the

provisions of the Paperwork Reduction Act (44 U.S.C. 3501 

et seq.);

 Are certified as not having a significant economic impact 

on a substantial number of small entities under the 

Regulatory Flexibility Act (5 U.S.C. 601 et seq.); 

 Do not contain any unfunded mandate or significantly or 

uniquely affect small governments, as described in the 

Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4);

 Do not have Federalism implications as specified in 

Executive Order 13132 (64 FR 43255, August 10, 1999);

 Are not an economically significant regulatory action based 

on health or safety risks subject to Executive Order 13045 

(62 FR 19885, April 23, 1997);

 Are not a significant regulatory action subject to 

Executive Order 13211 (66 FR 28355, May 22, 2001); 

 Are not subject to requirements of Section 12(d) of the 

National Technology Transfer and Advancement Act of 1995 

(15 U.S.C. 272 note) because application of those 

requirements would be inconsistent with the CAA; and 
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

77

 Do not provide EPA with the discretionary authority to 

address disproportionate human health or environmental 

effects with practical, appropriate, and legally 

permissible methods under Executive Order 12898 (59 FR 

7629, February 16, 1994).

In addition, this proposed rule does not have tribal 

implications as specified by Executive Order 13175 (65 FR 67249, 

November 9, 2000), because the SIP is not approved to apply in 

Indian country located in the State, and EPA notes that it will 

not impose substantial direct costs on tribal governments or 

preempt tribal law. In addition, there are no federally 

recognized tribes located within the Sacramento PM10

nonattainment area. 

List of Subjects

40 CFR Part 52

Environmental protection, Air pollution control, 

Incorporation by reference, Intergovernmental relations, 

Nitrogen dioxide, Particulate matter, Reporting and 

recordkeeping requirements, Sulfur dioxide.
This document is a prepublication version signed by EPA Acting Regional 

Administrator Alexis Strauss on July 12, 2013. We have taken steps to ensure 

the accuracy of this version, but it is not the official version.

78

40 CFR Part 81

Environmental protection, Air pollution control, National 

parks, Wilderness areas.

____________________ ________________________

Dated: Alexis Strauss

Acting Regional Administrator,

Region IX.