ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2010-0516; FRL- ]

Approval and Promulgation of Implementation Plans; California;

2008 San Joaquin Valley PM2.5 Plan and 2007 State Strategy

AGENCY: U.S. Environmental Protection Agency (EPA).

ACTION: Proposed rule.

SUMMARY: EPA is proposing to approve in part and disapprove in 

part state implementation plan (SIP) revisions submitted by 

California to provide for attainment of the 1997 fine 

particulate matter (PM2.5) national ambient air quality standards 

in the San Joaquin Valley (SJV). These SIP revisions are the SJV 

2008 PM2.5 Plan (revised 2010 and 2011) and SJV-related 

provisions of the 2007 State Strategy (revised 2009 and 2011). 

EPA is proposing to approve the emissions inventories; air 

quality modeling; the reasonably available control 

measures/reasonably available control technology, reasonable 

further progress, and attainment demonstrations; and the 

transportation conformity motor vehicle emissions budgets. EPA 

is also proposing to grant California's request to extend the 

attainment deadline for the SJV to April 5, 2015 and to approve 

commitments to measures and reductions by the SJV Air Pollution 

Control District and the California Air Resources Board.

Finally, it is proposing to disapprove the SIP’s contingency 
2

measures. This proposed rule amends EPA’s November 30, 2010

proposed rule (75 FR 74518) on the SJV 2008 PM2.5 Plan and 2007 

State Strategy.

DATE: Any comments must be received on or before [Insert date 30 

days from the date of publication in the Federal Register].

ADDRESSES: Submit comments, identified by docket number EPA-R09-

OAR-2010-0516, by one of the following methods:

Federal eRulemaking Portal: www.regulations.gov. Follow the 

on-line instructions.

E-mail: wicher.frances@epa.gov

Mail or deliver: Frances Wicher, Office of Air Planning 

(AIR-2), U.S. Environmental Protection Agency Region 9, 75 

Hawthorne Street, San Francisco, CA 94105.

Instructions: All comments will be included in the public docket 

without change and may be made available online at 

www.regulations.gov, including any personal information 

provided, unless the comment includes Confidential Business 

Information (CBI) or other information for which 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 www.regulations.gov or e-mail. 

The www.regulations.gov website is an “anonymous access” system, 

and EPA will not know your identity or contact information 

unless you provide it in the body of your comments. If you send 
3

e-mail directly to EPA, your e-mail address will be 

automatically captured and included as part of the public 

comment. If EPA cannot read your comments due to technical 

difficulties and cannot contact you for clarification, EPA may 

not be able to consider your comments.

Docket: The index to the docket for this action is available 

electronically at www.regulations.gov and in hard copy at EPA 

Region 9, 75 Hawthorne Street, San Francisco, California. While 

all documents in the docket are listed in the index, some may be 

publicly available only at the hard copy location (e.g., 

copyrighted material) and some may not be publicly available at 

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 below.

Copies of the SIP materials are also available for 

inspection at the following locations:

California Air Resources Board, 2020 L Street, Sacramento, 

California 95812

San Joaquin Valley Air Pollution Control District, 1990 E. 

Gettysburg, Fresno, California 93726.

The SIP materials are also electronically available at: 

www.valleyair.org/Air_Quality_Plans/PM_Plans.htm and 

www.arb.ca.gov/planning/sip/sip.htm.
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FOR FURTHER INFORMATION CONTACT: Frances Wicher, Air Planning 

Office (AIR-2), U.S. Environmental Protection Agency, Region 9, 

(415) 972-3957, wicher.frances@epa.gov

SUPPLEMENTARY INFORMATION: Throughout this document, “we”, “us” 

and “our” refer to EPA.

Table of Contents

I. The PM2.5 NAAQS and the San Joaquin Valley PM2.5 Nonattainment 

Area

II. California State Implementation Plan Submittals to Address 

PM2.5 Nonattainment in the San Joaquin Valley

A. California’s SIP Submittals

1. SJV 2008 PM2.5 Plan

2. CARB 2007 State Strategy

3. CARB 2011 Progress Report

B. CAA Procedural Requirements for SIP Submittals

III. EPA’s 2010 Proposed Action on the SJV 2008 PM2.5 SIP

IV. CAA and Regulatory Requirements for PM2.5 Attainment SIPs

V. Review of the SJV 2008 PM2.5 Plan and the SJV Portion of the 

Revised 2007 State Strategy

A. Emissions Inventories

1. Requirements for Emissions Inventories

2. Emissions Inventories in the SJV PM2.5 SIP

3. Proposed Action on the Emissions Inventories
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B. Reasonably Available Control Measures/Reasonably Available 

Control Technology Demonstration and Adopted Control Strategy

1. Requirements for RACM/RACT

2. RACM/RACT Demonstration in the SJV PM2.5 SIP

a. The District’s RACM/RACT Analysis and Adopted Control 

Strategy

b. CARB’s RACM Analysis and Adopted Control Strategy

c. The Local Jurisdictions’ RACM Analysis

3. Proposed Actions on RACM/RACT Demonstration and Adopted 

Control Strategy

C. Attainment Demonstration

1. Requirements for Attainment Demonstrations

2. Air Quality Modeling in the SJV 2008 PM2.5 Plan

3. PM2.5 Attainment Plan Precursors Addressed in the SJV 2008 

PM2.5 SIP

4. Extension of the Attainment Date

5. Attainment Demonstration

a. Enforceable Commitments

i. The Commitment Represents a Limited Portion of Required 

Reductions

ii. The State is Capable of Fulfilling its Commitment

iii. The Commitment is for a Reasonable and Appropriate 

Timeframe

6. Proposed Action on the Attainment Demonstration
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D. Reasonable Further Progress Demonstration

1. Requirements for RFP

2. The RFP Demonstration in the SJV 2008 PM2.5 Plan

3. Proposed Action on the RFP Demonstration

E. Contingency Measures

1. Requirements for Contingency Measures

2. Contingency Measures in the SJV 2008 PM2.5 Plan

3. Proposed Action on the Contingency Measures

F. Motor Vehicle Emissions Budgets for Transportation Conformity

1. Requirements for Motor Vehicle Emissions Budgets

2. Motor Vehicle Emissions Budgets in the SJV 2008 PM2.5 Plan

3. Updated Motor Vehicle Emissions Budgets in the 2011 Progress 

Report and Proposed Revisions

4. Proposed Action on the Motor Vehicle Emissions Budget

5. Proposed Action on the Trading Mechanism

VI. EPA’s Proposed Actions and Potential Consequences

A. EPA’s Proposed Approvals and Disapprovals

B. CAA Consequences of a Final Disapproval

VII. Statutory and Executive Order Reviews

I. The PM2.5 NAAQS and the San Joaquin Valley PM2.5 Nonattainment 

Area 

On July 18, 1997 (62 FR 36852), EPA established new 

national ambient air quality standards (NAAQS) for PM2.5, 
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particulate matter with a diameter of 2.5 microns or less, 

including annual standards of 15.0 micrograms per cubic meter 

(μg/m3) based on a 3-year average of annual mean PM2.5

concentrations and 24-hour (daily) standards of 65 μg/m3 based on 

a 3-year average of the 98th percentile of 24-hour 

concentrations. 40 CFR § 50.7. EPA established these standards 

after considering substantial evidence from numerous health 

studies demonstrating that serious health effects are associated 

with exposures to PM2.5 concentrations above the levels of these 

standards.

Epidemiological studies have shown statistically 

significant correlations between elevated PM2.5 levels and 

premature mortality. Other important health effects associated 

with PM2.5 exposure include aggravation of respiratory and 

cardiovascular disease (as indicated by increased hospital 

admissions, emergency room visits, absences from school or work, 

and restricted activity days), changes in lung function and 

increased respiratory symptoms, as well as new evidence for more 

subtle indicators of cardiovascular health. Individuals 

particularly sensitive to PM2.5 exposure include older adults, 

people with heart and lung disease, and children. See EPA, Air 

Quality Criteria for Particulate Matter, No. EPA/600/P–99/002aF 

and EPA/600/P–99/002bF, October 2004.
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PM2.5 can be emitted directly into the atmosphere as a solid 

or liquid particle (primary PM2.5 or direct PM2.5) or can be 

formed in the atmosphere as a result of various chemical 

reactions from precursor emissions of nitrogen oxides, sulfur 

oxides, volatile organic compounds, and ammonia (secondary 

PM2.5). See 72 FR 20586, 20589 (April 25, 2007).

Following promulgation of a new or revised NAAQS, EPA is 

required by Clean Air Act (CAA) section 107(d) to designate 

areas throughout the nation as attaining or not attaining the 

NAAQS. On January 5, 2005, EPA published initial air quality 

designations for the 1997 PM2.5 NAAQS, using air quality 

monitoring data for the three-year periods of 2001-2003 or 2002-

2004. 70 FR 944. These designations became effective on April 5, 

2005.1

EPA designated the San Joaquin Valley (SJV) nonattainment 

for both the 1997 annual and 24-hour PM2.5 standards. 40 CFR § 

81.305. The SJV PM2.5 nonattainment area is home to 4 million 

 

1 On October 17, 2006, EPA strengthened the 24-hour PM2.5

NAAQS by lowering the level to 35 μg/m3. At the same time, it 

retained the level of the annual PM2.5 standards at 15.0 μg/m3. 71 

FR 61144. On November 13, 2009, EPA designated areas, including 

the SJV, with respect to the revised 24-hour NAAQS. 74 FR 58688. 

California is now required to submit an attainment plan for the 

35 μg/m324-hour standards no later than 3 years after the 

effective date of the designation, that is, no later than 

December 14, 2012. In this preamble, all references to the PM2.5

NAAQS, unless otherwise specified, are to the 1997 24-hour PM2.5

standards of 65 μg/m3 and annual standards of 15 μg/m3 as 

codified in 40 CFR § 50.7.
9

people and is the nation’s leading agricultural area. Stretching 

over 250 miles from north to south and averaging 80 miles wide, 

it is partially enclosed by the Coast Mountain range to the 

west, the Tehachapi Mountains to the south, and the Sierra 

Nevada range to the east. It encompasses over 23,000 square 

miles and includes all or part of eight counties: San Joaquin, 

Stanislaus, Merced, Madera, Fresno, Tulare, Kings, and the 

valley portion of Kern. For a precise description of the 

geographic boundaries of the San Joaquin Valley PM2.5

nonattainment area, see 40 CFR § 81.305. The local air district 

with primary responsibility for developing a plan to attain the 

PM2.5 NAAQS in this area is the San Joaquin Valley Unified Air 

Pollution Control District (SJVUAPCD or District).

Ambient annual and 24-hour PM2.5 levels in the urban 

Bakersfield area in the southern SJV are the highest recorded in 

the United States at 21.2 μg/m3 and 65 μg/m3, respectively, for 

the 2008-2010 period.2 These values have declined significantly 

since 2001. See Figures IB-1 and IB-2 in the technical support 

document (TSD) for this proposal.

 

2 See EPA, Air Quality System, Design Value Report, June 1, 

2011. These values are the highest design values in the SJV. A 

design value is an ambient concentration calculated using a 

specific methodology from monitored air quality data and is used 

to compare an area’s air quality to a NAAQS. The methodologies 

for calculating design values for the annual and 24-hour PM2.5

NAAQS are found in 40 CFR part 50 Appendix N, Sections 1(c)(1)

and (c)(2), respectively.
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The levels and composition of ambient PM2.5 in the SJV 

differ by season. 2008 PM2.5 Plan, Figures H-4 and H-5. Higher 

PM2.5 concentrations occur during the winter, between late 

November and February, when ambient PM2.5 is dominated by 

ammonium nitrate (a secondary particulate formed from nitrogen 

oxides (NOx) and ammonia emissions) and directly-emitted 

particulates, such as wood smoke. During the winter, the SJV 

experiences extended periods of stagnant weather with cold foggy 

conditions which are conducive to the formation of ammonium 

nitrate and which encourage wood burning. During the summer, 

PM2.5 levels generally remain below 15 μg/m3, the level of the 

annual standards. 2008 PM2.5 Plan, Figures H-6 and H-7.

II. California’s State Implementation Plan Submittals to Address 

PM2.5 Nonattainment in the San Joaquin Valley

A. California’s SIP Submittals

Designation of an area as nonattainment starts the process 

for a state to develop and submit to EPA a state implementation 

plan (SIP) under title 1, part D of the CAA. This SIP must 

include, among other things, a demonstration of how the NAAQS 

will be attained in the nonattainment area as expeditiously as 

practicable but no later than the date required by the CAA. 

Under CAA section 172(b), a state has up to three years after an 

area’s designation as nonattainment to submit its SIP to EPA. 
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For the 1997 PM2.5 NAAQS, these SIPs were due April 5, 2008. 40 

CFR § 51.1002(a).

California has made five SIP submittals to address the 

CAA’s PM2.5 planning requirements in the San Joaquin Valley. The 

two principal ones are the SJVAPCD’s 2008 PM2.5 Plan (2008 PM2.5

Plan or Plan) and the California Air Resources Board’s (CARB) 

State Strategy for California’s 2007 State Implementation Plan 

(2007 State Strategy). Together the 2008 PM2.5 Plan and the State 

Strategy present a comprehensive and innovative strategy for 

attaining the 1997 PM2.5 standards in the SJV.

In addition to these submittals, the District and State 

have also submitted numerous rules that contribute to improving 

air quality in the San Joaquin Valley. See Appendices A and B of 

the TSD for this proposal.

1. SJV 2008 PM2.5 Plan

The 2008 PM2.5 Plan was adopted by the District's Governing 

Board on April 30, 2008 and by CARB on May 22, 2008 and 

submitted to EPA on June 30, 2008.3 It includes an attainment 

demonstration, commitments by the District to adopt control 

 

3 See SJVUAPCD Governing Board Resolution: In the Matter of 

Adopting the San Joaquin Valley Unified Air Pollution Control 

District 2008 PM2.5 Plan, April 30, 2008 (SJVUAPCD Governing 

Board Resolution), CARB Resolution No. 08-28, May 22, 2008; and 

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

Nastri, Regional Administrator, EPA Region 9, June 30, 2008, 

with enclosures.
12

measures to achieve emissions reductions from sources under its 

jurisdiction (primarily stationary sources), and motor vehicle 

emissions budgets (MVEB) used for transportation conformity 

purposes. The attainment demonstration includes air quality 

modeling, a reasonable further progress (RFP) plan, an analysis 

of reasonably available control measures/reasonably available 

control technology (RACM/RACT), base year and projected year 

emissions inventories, and contingency measures. The 2008 PM2.5

Plan also includes the District’s demonstration that attainment 

of the PM2.5 standards in the SJV will require significant 

reductions in direct PM2.5 and NOx emissions (25 percent and 50 

percent from 2005 levels, respectively) in addition to 

reductions in SOx emissions, that the most expeditious date for

attaining the 1997 PM2.5 NAAQS in the San Joaquin Valley is April 

5, 2015, and that all controls necessary for attainment by that 

date will be in place by the attainment year of 2014.4 On 

September 15, 2010, CARB submitted a minor revision to the 2008 

PM2.5 Plan's control strategy to extend the adoption date for one 

control measure.5

 

4 While the applicable attainment date for PM2.5 areas with

a full five-year extension is April 5, 2015, reductions must be 

implemented by 2014 to achieve attainment by that date. See 40 

CFR § 51.1007(b). We, therefore, refer to 2014 as the attainment 

year and April 5, 2015 as the attainment date.

5 See letter, James N. Goldstene, Executive Officer, CARB,

to Jared Blumenfeld, Regional Administrator, EPA Region 9, 
13

2. CARB 2007 State Strategy

To demonstrate attainment, the 2008 PM2.5 Plan relies in 

part on measures in CARB’s 2007 State Strategy. The 2007 State 

Strategy was adopted on September 27, 2007 and submitted to EPA 

on November 16, 2007.6 It describes CARB’s overall approach to 

addressing, in conjunction with local plans, attainment of both 

the 1997 PM2.5 and 8-hour ozone NAAQS not only in the San Joaquin 

Valley but also in California’s other nonattainment areas such 

as the South Coast Air Basin. It also includes CARB’s 

commitments to propose 15 defined State measures7 and to obtain 

specific amounts of aggregate emissions reductions of direct 

PM2.5 and NOx in the SJV from sources under the State’s 

jurisdiction, which are primarily on- and off-road motor 

vehicles and engines.

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 

 

September 15, 2010, with enclosures.

6 See CARB Resolution No. 07-28, September 27, 2007 with 

attachments and letter, James N. Goldstene, Executive Officer, 

CARB, to Wayne Nastri, Regional Administrator, EPA Region 9,

November 16, 2007, with enclosures.

7 The 2007 State Strategy also includes measures to be 

implemented by the California Bureau of Automotive Repair (Smog

Check improvements) and the California Department of Pesticide 

Regulation (VOC reductions from pesticide use). See 2007 State 

Strategy, pp. 64-65 and CARB Resolution 7-28, Attachment B, p. 

8.
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Implementation of the 2007 State Strategy,” dated March 24, 

2009, adopted April 24, 2009 (2009 State Strategy Status Report)8

which updates the 2007 State Strategy to reflect its 

implementation during 2007 and 2008.

In today's proposal, we are only evaluating those portions 

of the 2007 State Strategy and its revisions (including the 2011 

revisions described below) that are relevant for attainment of 

the PM2.5 standards in the San Joaquin Valley.

3. CARB 2011 Progress Report

On May 18, 2011, CARB submitted the “Progress Report on 

Implementation of PM2.5 State Implementation Plans (SIP) for the 

South Coast and San Joaquin Valley Air Basins and Proposed SIP 

Revisions,” dated March 29, 2011 and adopted April 28, 2011 

(2011 Progress Report). This submittal, which updates both the 

2007 State Strategy and SJV 2008 PM2.5 Plan, shows that both CARB 

and the District have made significant progress in meeting their 

commitments to adopt measures and to reduce emissions. More 

specifically, it updates CARB’s rulemaking calendar in the 2007 

State Strategy (as revised in 2009) to reflect the current 

 

8 See CARB Resolution No. 09-34, April 21, 2009, with 

attachments and letter, James N. Goldstene, Executive Officer, 

CARB, to Laura Yoshii, Acting 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 is for informational purposes only. See Attachment A 

to the CARB Resolution No. 09-34.
15

status of CARB’s adopted measures and to change the expected 

action dates for several measures. It also updates the RFP 

demonstration, contingency measures, and transportation 

conformity MVEB in the 2008 PM2.5 Plan to reflect rule adoptions, 

changes to activity and emissions factors for certain source 

categories, and the impact on projected future emissions levels 

in the SJV of the recent economic recession.

9

The District has also prepared a report documenting its 

progress in implementing the 2008 PM2.5 Plan. See SJVUAPCD, 2008 

PM2.5 Plan Progress Report, draft March 2011 (SJV PM2.5 Progress 

Report). This report, which is informational only and does not 

include any revisions to the SIP, was posted for public comment 

in March and was presented to the District’s Governing Board at 

its June 2011 meeting. 

Future references in this proposal to the SJV 2008 PM2.5

Plan and the 2007 State Strategy will be to the Plan as revised

in 2010 and 2011 and the Strategy as revised in 2009 and 2011, 

respectively, unless otherwise noted.

B. CAA Procedural Requirements for SIP Submittals

CAA sections 110(a)(1) and (2) and 110(l) require a state 

to provide reasonable public notice and opportunity for public 

 

9 On June 21, 2011, CARB posted to its website technical 

revisions to the updated MVEB in the 2011 Progress Report. See

www.arb.ca.gov/planning/sip/2007sip/2007sip.htm. We discuss 

these revisions in the section on MVEB below.
16

hearing prior to the adoption and submittal of a SIP or SIP 

revision. To meet this requirement, every SIP submittal should 

include evidence that adequate public notice was given and an 

opportunity for a public hearing was provided consistent with 

EPA’s implementing regulations in 40 CFR § 51.102.

Both the District and CARB have satisfied applicable 

statutory and regulatory requirements for reasonable public 

notice and hearing prior to adoption and submittal of the 2008 

PM2.5 Plan. The District conducted public workshops, provided 

public comment periods, and held a public hearing prior to the 

adoption of the Plan on April 30, 2008. See 2008 PM2.5 Plan, 

Appendix J and SJVUAPCD Governing Board Resolution, p. 3. CARB 

provided the required public notice and opportunity for public 

comment prior to its May 22, 2008 public hearing on the Plan. 

See CARB Resolution No. 08-28. The District also provided the 

required public notice and hearing on the 2010 revision to the 

Plan. See SJVUAPCD Governing Board Resolution No. 10-06-18.

CARB conducted public workshops, provided public comment 

periods, and held a public hearing prior to the adoption of the 

2007 State Strategy on September 27, 2007. See CARB Resolution 

No. 07-28. CARB also provided the required public notice, 

opportunity for public comment, and a public hearing prior to 

its April 24, 2009 adoption of the 2009 State Strategy Status 

Report and its April 28, 2011 adoption of the 2011 Progress 
17

Report. See CARB Resolution No. 09-34 and CARB Resolution No. 

11-24.

The SIP submittals include proof of publication for notices 

of District and CARB public hearings, as evidence that all 

hearings were properly noticed. We find, therefore, that each of 

the five submittals that comprise the SJV PM2.5 SIP meets the 

procedural requirements for public notice and hearing in CAA 

sections 110(a) and 110(l).

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 EPA has not 

affirmatively determined to be complete or incomplete will 

become complete by operation of law six months after the date of 

submittal. EPA’s SIP completeness criteria are found in 40 CFR 

part 51, Appendix V.

The June 30, 2008 submittal of the 2008 PM2.5 Plan became 

complete by operation of law on December 30, 2008. We determined 

that the 2010 revision to the Plan was complete on September 23, 

2010.10 The November 16, 2007 submittal of the 2007 State 

Strategy and the August 12, 2009 submittal of the 2009 revisions 

to the Strategy became complete by operation of law on May 16, 

 

10 Letter, Deborah Jordan, EPA-Region 9 to James Goldstene, 

CARB, September 23, 2010.
18

2008 and February 12, 2010, respectively. We determined that the 

2011 revision to the Plan was complete on June 13, 2011.11

III. EPA’s 2010 Proposed Action on the SJV PM2.5 SIP

This is the second time that EPA has proposed action on 

California’s SIP to address attainment of the 1997 PM2.5

standards in the SJV. On November 30, 2010 (75 FR 74518), EPA 

proposed to approve in part and disapprove in part the 2008 PM2.5

Plan and the related portions of the 2007 State Strategy. 

Specifically, we proposed to approve the emissions 

inventories as meeting the applicable requirements of the CAA 

and PM2.5 implementation rule in 40 CFR part 41, subpart Z. We 

also proposed to approve the District’s and CARB’s commitments 

to adopt and implement specific measures and to achieve specific 

aggregate emissions reductions because their approval would 

strengthen the SIP.

In addition, we proposed to find that volatile organic 

compounds (VOC) are a PM2.5 attainment plan precursor for the 

1997 PM2.5 NAAQS in the SJV and therefore needed to be addressed 

in the 2008 PM2.5 SIP’s RACM/RACT, RFP, and attainment 

demonstrations and in other PM2.5 SIP control requirements, such 

as contingency measures. As submitted prior to our November 2010 

proposal, the Plan did not treat VOC as an attainment plan 

 

11 Letter, Deborah Jordan, EPA-Region 9 to James Goldstene, 

CARB, June 13, 2011.
19

precursor but did contain information indicating that 

significant reductions in VOC emissions could significantly 

reduce ambient PM2.5 concentrations in the SJV.

We proposed to disapprove the air quality modeling analysis 

on which the 2008 PM2.5 Plan’s RACM/RACT, RFP, and attainment 

demonstrations and the State’s attainment date extension request 

were based because the Plan did not include sufficient 

documentation and analyses for EPA to determine the modeling’s 

adequacy.

Based on our proposed finding that VOC should be a PM2.5

attainment plan precursor and our proposed disapproval of the 

air quality modeling, we proposed to disapprove the 2008 PM2.5

Plan’s RACM/RACT, RFP, and attainment demonstrations and the 

contingency measures as not meeting the applicable requirements 

of the CAA and PM2.5 implementation rule. We proposed to 

disapprove the attainment demonstration for the additional 

reason that it relied too extensively on enforceable commitments 

to reduce emissions in place of fully-adopted and submitted 

rules. We also proposed to disapprove the transportation 

conformity MVEB for the RFP milestone years of 2009 and 2012 and 

the attainment year of 2014 because they were derived from 

unapprovable RFP and attainment demonstrations. Finally, based 

also on our proposed finding on VOC and our proposed disapproval 

of the air quality modeling as well as our proposed disapproval 
20

of the RACM/RACT and attainment demonstrations, we proposed to 

not grant the State’s request to extend the attainment date for 

the PM2.5 NAAQS in the SJV to April 5, 2015.

During the comment period for the November 2010 proposal, 

we received five comment letters from the public as well as 

comment letters from CARB and the District. Subsequent to the 

close of the comment period, CARB adopted and submitted 

revisions to the SJV PM2.5 Plan and 2007 State Strategy After 

considering information contained in the comment letters and 

these supplemental SIP submittals, we have substantially amended 

our November 2010 proposed action as described below. EPA will 

consider all significant comments submitted in response to both 

its November 2010 proposal and today’s proposal before taking 

final action on the SJV PM2.5 SIP. However, EPA strongly 

encourages those who submitted comments on the November 2010 

proposal to submit revised comments reflecting today’s amended 

proposal during the comment period on this amended proposal. 

IV. CAA and Regulatory Requirements for PM2.5 Attainment 

SIPs

EPA is implementing the 1997 PM2.5 NAAQS under Title 1, Part 

D, subpart 1 of the CAA, which includes section 172, 

“Nonattainment plan provisions.” Section 172(a)(2) requires that 

a PM2.5 nonattainment area attain the NAAQS “as expeditiously as 

practicable” but no later than five years from the date of the 
21

area's designation as nonattainment. This section also allows 

EPA to grant up to a five-year extension of an area’s attainment 

date based on the severity of the area's nonattainment and the 

availability and feasibility of controls. EPA designated the SJV 

as nonattainment for the 1997 PM2.5 NAAQS effective April 5, 

2005, and thus the applicable attainment date is no later than 

April 5, 2010 or, should EPA grant a full five-year extension, 

no later than April 5, 2015.

Section 172(c) contains the general statutory planning 

requirements applicable to all nonattainment areas, including 

the requirements for emissions inventories, RACM/RACT, 

attainment demonstrations, RFP demonstrations, and contingency 

measures.

On April 25, 2007, EPA issued the Clean Air Fine Particle 

Implementation Rule for the 1997 PM2.5 NAAQS. 72 FR 20586, 

codified at 40 CFR part 51, subpart Z (PM2.5 implementation 

rule). The PM2.5 implementation rule and its preamble address the 

statutory planning requirements for emissions inventories, 

RACM/RACT, attainment demonstrations including air quality 

modeling requirements, RFP demonstrations, and contingency 

measures. This rule also addresses other matters such as which 

PM2.5 precursors must be addressed by the state in its attainment 
22

SIP and applicable attainment dates.12 We discuss each of these 

CAA and regulatory requirements for PM2.5 attainment plans in 

more detail below.

V. Review of the SJV 2008 PM2.5 SIP

 

12 In June 2007, a petition to the EPA Administrator was 

filed on behalf of several public health and environmental 

groups requesting reconsideration of four provisions in the PM2.5

implementation rule. See Earthjustice, Petition for 

Reconsideration, “In the Matter of Final Clean Air Fine Particle

Implementation Rule,” June 25, 2007. These provisions are 1) the 

presumption that compliance with the Clean Air Interstate Rule 

satisfies the NOx and SO2 RACT requirements for electric 

generating units; 2) the deferral of the requirement to 

establish emission limits for condensable particulate matter

(CPM) until January 1, 2011; 3) revisions to the criteria for 

analyzing the economic feasibility of RACT; and 4) the use of 

out-of-area emissions reductions to demonstrate RFP. These 

provisions are found in the PM2.5 implementation rule and 

preamble at 72 FR 20586 at 20623-20628, 40 CFR § 51.1002(c), 72 

FR 20586, 20619-20620 and 20636, respectively. On May 13, 2010, 

EPA granted the petition with respect to the fourth issue. 

Letter, Gina McCarthy, EPA, to David Baron and Paul Cort, 

Earthjustice, May 13, 2010. On April 25, 2011, EPA granted the 

petition with respect to the first and third issues but denied 

the petition with respect to the second issue given that the 

deferral period for CPM emissions limits had already ended. 

Letter, Lisa P. Jackson, EPA, to Paul Cort, Earthjustice, April 

25, 2011. EPA intends to publish a Federal Register notice that 

will announce the granting of the latter petition with respect 

to certain issues and to initiate a notice and comment process 

to consider proposed changes to the 2007 PM2.5 implementation 

rule.

Neither the District nor the State relied on the first, 

third, or fourth of these provisions in preparing the 2008 PM2.5

Plan or the 2007 State Strategy. The District has deferred some, 

but not all, CPM limits in its rules. This limited deferral does 

not affect the proposed approvals of the SJV PM2.5 SIP’s 

RACM/RACT and expeditious attainment demonstrations. EPA will 

evaluate any rule adopted or revised by the District after 

January 1, 2011 to assure that it appropriately addresses CPM.
23

We summarize our evaluation of the SJV PM2.5 SIP’s 

compliance with applicable CAA and EPA regulatory requirements 

below. Our detailed evaluation can be found in the TSD for this 

proposal which is available online at www.regulations.gov in 

docket number EPA-R09-OAR-2010-0516 or from the EPA contact 

listed at the beginning of this notice.

A. Emissions Inventories

1. Requirements for Emissions Inventories

CAA section 172(c)(3) requires a state to submit a plan 

provision that includes a “comprehensive, accurate, current 

inventory of actual emissions from all sources of the relevant 

pollutant.” The PM2.5 implementation rule requires a state to 

include direct PM2.5 emissions and emissions of all PM2.5 

precursors in this inventory, even if it has determined that 

control of any of these precursors is not necessary for 

expeditious attainment. 40 CFR § 51.1008(a)(1) and 72 FR 20586 

at 20648. Direct PM2.5 includes condensable particulate matter. 

40 CFR § 51.1000. PM2.5 precursors are NOx, SO2, VOC, and ammonia.

Id. The inventories should meet the data requirements of EPA’s 

Consolidated Emissions Reporting Rule (codified at 40 CFR part 

51 subpart A) and include any additional inventory information 

needed to support the SIP’s attainment demonstration and (where 

applicable) RFP demonstration. 40 CFR § 51.1008(a)(1) and (2).
24

Baseline emissions inventories are required for the 

attainment demonstration and for meeting RFP requirements. As 

determined on the date of designation, the base year for these

inventories should be the most recent calendar year for which a 

complete inventory was required to be submitted to EPA. The 

emissions inventory for calendar year 2002 or other suitable 

year should be used attainment planning and RFP plans for areas 

initially designated nonattainment for the PM2.5 NAAQS in 2005. 

40 CFR § 51.1008(b).

EPA has provided additional guidance for PM2.5 emissions 

inventories in “Emissions Inventory Guidance for Implementation 

of Ozone and Particulate Matter NAAQS and Regional Haze 

Regulations,” November 2005 (EPA–454/R–05–001).

2. Emissions Inventories in the SJV PM2.5 SIP

The base year and future year baseline planning inventories 

for direct PM2.5 and all PM2.5 precursors for the SJV PM2.5

nonattainment area together with additional documentation for 

the inventories are found in Appendix B of the 2008 PM2.5 Plan. 

Both average winter day and average annual day inventories are 

provided for the Plan’s base year of 2005 and each baseline year 

from 2009 to 2014. These base year and baseline inventories 

incorporate reductions from federal, State, and District 

measures adopted prior to 2007. See 2008 PM2.5 Plan, p. B-1 and 

2007 State Strategy, Appendix A, p. 1. A winter inventory is 
25

provided because the majority of high PM2.5 days in the SJV occur 

during the winter months between November and February. 2008 

PM2.5 Plan, Figures H-4 and H-5.

Both base year and baseline inventories use the most 

current version of California’s mobile source emissions model, 

EMFAC2007, for estimating on-road motor vehicle emissions. EPA 

has approved this model for use in SIPs and transportation 

conformity analyses. 73 FR 3464 (January 18, 2008). 

Table 1 is a summary of the average annual day inventories 

of direct PM2.5 and PM2.5 precursors for the base year of 2005. 

These inventories provide the basis for the control measure 

analysis and the RFP and attainment demonstrations in the 2008 

PM2.5 Plan.

As a starting point for the 2008 PM2.5 Plan’s inventories, 

the District used CARB’s inventory for the year 2002. An example 

of this inventory and CARB’s documentation for its inventories 

can be found in Appendices A and F, respectively, of the 2007 

State Strategy. The 2002 inventory for the SJV was projected to 

2005 and future years using CARB’s California Emissions 

Forecasting System (CEFSv 1.06). See 2008 PM2.5 Plan, p. B-1.

Table 1

San Joaquin Valley Emissions Inventory Summary for Direct 

PM2.5 and PM2.5 Precursors for the 2005 Base Year

(tons per annual average day)

Emissions Direct NOx SO2 VOC Ammonia
26

Inventory Category PM2.5

2005 2005 2005 2005 2005

Stationary Sources 13.3 80.1 20.4 121.5 19.8

Area Sources 51.5 13.5 0.9 140.7 355.9

On-Road Mobile 

Sources 12.1 327.9 2.6 94.8 6.2

Off-Road Mobile 

Sources 9.0 153.9 2.4 62.7 0

Total 86.0 575.4 26.4 419.8 382.0

3. Proposed Action on the Emissions Inventories

The inventories in the SJV PM2.5 SIP are based on the most 

current and accurate information available to the State and 

District at the time the Plan was developed and submitted 

(including using the latest EPA-approved version of California’s 

mobile source emissions model, EMFAC2007), address 

comprehensively all source categories in the SJV, and are 

consistent with EPA’s inventory guidance. For these reasons, EPA 

is proposing to approve the 2005 base year emissions inventory 

in the SJV PM2.5 SIP as meeting the requirements of CAA section 

172(c)(3) and 40 CFR § 51.1008(a)(1) and to find that the 

baseline inventories in the SJV PM2.5 SIP provide an adequate 

basis for the RACM/RACT, RFP, and attainment demonstrations. We 

provide more detail on our review of the base year inventory as 

well as the projected year inventories in section II.A. of the 

TSD.

Since late 2007, California has experienced an economic 

recession that has greatly reduced current levels of economic 
27

activity in the State’s construction and goods movement sectors. 

The recession has resulted in lowered projected future levels of 

activity in this sector. 2011 Progress Report, Appendix E. As a 

result, projected emissions levels from these categories are now 

substantially lower than those projected for 2008 and later in 

the Plan as submitted in 2008. At this time, California is 

addressing these recession impacts on future economic activity 

through adjustments to the baseline inventories for specific 

source categories. 2011 Progress Report, Appendix E. There are 

no recession-related adjustments to the 2005 base year inventory 

in the SJV 2008 PM2.5 Plan.

CARB also made technical changes to the inventories for 

diesel trucks, buses, and certain categories of off-road mobile 

source engines as part of its December 2010 rulemaking amending 

the In-Use On-Road Truck and Bus Rule and In-Use Off-Road Engine 

Rule. Id. The State estimates that these changes collectively 

reduce the 2005 base year NOx inventory in the SJV by 

approximately 6 percent and the PM2.5 inventory by 5 percent.13

These change are small given the normal and unavoidable 

uncertainties in all emissions inventories and, therefore, do 

not change our basis for proposing to approve the base year 

 

13 See attachment 1 to the letter, Lynn Terry, Deputy 

Executive Officer, CARB, to Elizabeth Adams, Deputy Director, 

Air Division, EPA Region 9, May 18, 2011 (CARB Progress Report 

supplement), in the docket for today’s proposal.
28

inventory or to find the baseline inventories adequate for SIP 

planning purposes. We discuss the impact of these changes on the 

Plan’s RFP and attainment demonstrations later in this notice. 

We note that the State and District are currently working 

on revisions to the SJV PM2.5 SIP to address the 2006 24-hour 

PM2.5 standards. These revisions are due to EPA in December 2012 

and will include the most current inventory information that is 

available.

B. Reasonably Available Control Measures/Reasonably Available 

Control Technology Demonstration and Adopted Control Strategy

1. Requirements for RACM/RACT

CAA section 172(c)(1) requires that each attainment plan 

“provide for the implementation of all reasonably available 

control measures as expeditiously as practicable (including such 

reductions in emissions from existing sources in the area as may 

be obtained through the adoption, at a minimum, of reasonably 

available control technology), and shall provide for attainment 

of the national primary ambient air quality standards.” EPA 

defines RACM as measures that a state finds are both reasonably 

available and contribute to attainment as expeditiously as 

practicable in its nonattainment area. Thus, what constitutes 

RACM/RACT in a PM2.5 attainment plan is closely tied to that 

plan’s expeditious attainment demonstration. 40 CFR § 51.1010; 

72 FR 20586 at 20612. States are required to evaluate RACM/RACT 
29

for direct PM2.5 and all of its attainment plan precursors. 40 

CFR 51.1002(c).

Consistent with subpart 1 of Part D of the CAA, EPA is 

requiring a combined approach to RACM and RACT for PM2.5

attainment plans. Subpart 1, unlike subparts 2 and 4, does not 

identify specific source categories for which EPA must issue 

control technology documents or guidelines for what constitutes 

RACT, or identify specific source categories for state and EPA 

evaluation during attainment plan development. 72 FR 20586 at 

20610. Rather, under subpart 1, EPA considers RACT to be part of 

an area's overall RACM obligation. Because of the variable 

nature of the PM2.5 problem in different nonattainment areas, EPA 

determined not only that states should have flexibility with 

respect to RACT and RACM controls but also that in areas needing 

significant emission reductions to attain the standards, 

RACT/RACM controls on smaller sources may be necessary to reach 

attainment as expeditiously as practicable. 72 FR 20586 at 

20612, 20615. Thus, under the PM2.5 implementation rule, RACT and 

RACM are those reasonably available measures that contribute to 

attainment as expeditiously as practicable in the specific 

nonattainment area. 40 CFR § 51.1010; 72 FR 20586 at 20612.

The PM2.5 implementation rule requires that attainment plans 

include the list of measures a state considered and information 

sufficient to show that the state met all requirements for the 
30

determination of what constitutes RACM/RACT in its specific 

nonattainment area. 40 CFR § 51.1010. In addition, the rule 

requires that the state, in determining whether a particular 

emissions reduction measure or set of measures must be adopted 

as RACM/RACT, consider the cumulative impact of implementing the 

available measures and to adopt as RACM/RACT any potential 

measures that are reasonably available considering technological 

and economic feasibility if, considered collectively, they would 

advance the attainment date by one year or more. Id. Any 

measures that are necessary to meet these requirements which are 

not already either federally promulgated, part of the state’s 

SIP, or otherwise creditable in SIPs must be submitted in 

enforceable form as part of a state’s attainment plan for the 

area. 72 FR 20586 at 20614.

A more comprehensive discussion of the RACM/RACT 

requirement for PM2.5 attainment plans and EPA’s guidance for it 

can be found in the PM2.5 implementation rule preamble (72 FR 

20586 at 20609-20633) and in section II.D. of the TSD.

2. RACM/RACT Demonstration in the SJV PM2.5 SIP

For the 2008 PM2.5 Plan and the 2007 State Strategy, the 

District, CARB, and the local agencies (through the SJV’s eight 

metropolitan planning organizations (MPO)) each undertook a 

process to identify and evaluate potential reasonably available 

control measures that could contribute to expeditious attainment 
31

of the PM2.5 standards in the SJV. These RACM/RACT analyses 

address control measures for sources of direct PM2.5, NOx and SO2, 

which are the State’s selected attainment plan precursors for 

the 1997 PM2.5 standards in SJV (see section V.C.3 below). We 

describe each agency’s efforts below.

a. District’s RACM/RACT Analysis and Adopted Control Strategy

The District’s RACM/RACT analysis, which focuses on 

stationary and area source controls, is described in Chapter 6 

and Appendix I of the 2008 PM2.5 Plan. To identify potential 

RACM/RACT, the District reviewed potential measures from a 

number of sources including EPA’s list of potential control 

measures in the preamble to the PM2.5 implementation rule (72 FR 

20586 at 20621), measures in other nonattainment areas’ plans, 

and measures suggested by the public during development of the 

2008 PM2.5 Plan. 2008 PM2.5 Plan, pp. 6-6 to 6-8. The identified 

potential measures, as well as existing District measures, are 

described by emissions inventory category in Appendix I. These 

measures address emissions of direct PM2.5, NOx and SO2. See 2008 

PM2.5 Plan, p. 6-8 and Appendix I. Potential RACM/RACT controls 

for VOC or ammonia were not specifically identified or 

evaluated.

From the set of identified potential controls for PM2.5, NOx, 

and SO2, the District selected measures for adoption and 

implementation based on the technological feasibility and 
32

practicality of emissions controls, the potential magnitude and 

timing of emissions reductions, cost effectiveness, and other 

acceptable criteria. 2008 PM2.5 Plan, p. 6-7.

After completing its RACM/RACT analysis for stationary and 

area sources under its jurisdiction, the District developed its 

“Stationary Source Regulatory Implementation Schedule” (2008 

PM2.5 Plan, Table 6-2) which gives the schedule for regulatory 

adoption and implementation of the selected RACM/RACT measures. 

The District also identified a number of source categories for 

which feasibility studies would be undertaken to refine the 

inventory and evaluate potential controls. These categories and 

the schedule for studying them are listed in Table 6-4 of the 

2008 PM2.5 Plan.

In the five years prior to the adoption of the 2008 PM2.5

Plan, the District developed and implemented comprehensive plans 

to address attainment of the PM10 standards (2003 PM10 Plan, 

approved 69 FR 30005 (May 26, 2004)), the 1-hour ozone standards 

(2004 Extreme Ozone Attainment Plan, approved 75 FR 10420 (March 

8, 2010)), and the 8-hour ozone standards (2007 Ozone Plan, 

submitted November 16, 2007). These plans for other NAAQS have 

resulted in the adoption by the District of many new rules and 

revisions to existing rules for stationary and area sources. For 

the most part, the District’s current rules are equivalent to or 

more stringent than those developed by other air districts. In 
33

addition to these stationary and area source measures, the 

District has also adopted an indirect source review rule, Rule 

9510, to address increased indirect emissions from new 

industrial, commercial and residential developments. See 

SJVUAPCD Rule 9510 “Indirect Source Review,” adopted December 

15, 2005, approved 76 FR 26609 (May 9, 2011). The District also 

operates incentive grant programs to accelerate turnover of 

existing stationary and mobile engines to cleaner units. See 

2008 PM2.5 Plan, Section 6.5 and SJV PM2.5 Progress Report, 

section 2.3.

For the 2008 PM2.5 Plan, the District identified and 

committed to adopt and implement 13 new control measures for 

direct PM2.5, NOx, and/or SOx. In Table 2 below, we list these 

measures, which mostly involve strengthening existing District 

rules, their anticipated and actual adoption dates and their 

current SIP approval status. As can be seen from Table 2, the 

District has met its intended rulemaking schedule with one 

exception and has only two rule actions remaining (S-COM-6 and 

S-COM-10). Table 6-3 in the Plan shows estimated emissions 

reductions from each rule for each year from 2009 to 2014; 

however, the District’s commitment is only to the aggregate 

emissions reductions of direct PM2.5, NOx, and SO2 in each year. 

2008 PM2.5 Plan, p. 6-9 and SJVUAPCD Governing Board Resolution, 

p. 5. We show these commitments in Table 3 below. In its SJV 
34

PM2.5 Progress Report, the District updated the reduction 

estimates to reflect the rules as adopted. See Table 4 below. 

Table 2

San Joaquin Valley Air Pollution Control District

2008 PM2.5 Plan Specific Rule Commitments

Measure 

Number District Rule

Expected

Adoption

Date

Actual 

Adoption 

Date

Current SIP Approval 

Status

S-AGR-1 4103 – Open Burning 2

nd Q – 2010 April 2010 Proposed approval

signed: June 29, 2011

S-COM-1 

4320 – Advanced 

Emissions Reductions 

for Boilers, Steam 

Generators and 

Process Heaters (> 5 

MMBtu/hr)

3

rd Q – 2008 October 

2008

Approved.

75 FR 1715 (January 

13, 2010)

S-COM-2 

4307 - Boilers, Steam 

Generators and 

Process Heaters (2 to 

5 MMBtu/hr)

3

rd Q – 2008 October 

2008

Approved.

76 FR 5276 (January 

31, 2011)

S-COM-3 

4308 - Boilers, Steam 

Generators and 

Process Heaters 

(0.075 to < 2 MM 

Btu/hr)

4

th Q – 2009 December 

2009

Approved. 

76 FR 16696 (March 

25, 2011)

S-COM-5 4703 - Stationary Gas 

Turbines 3

rd Q – 2007 September 

2007

Approved.

74 FR 53888 (October 

21, 2009)

S-COM-6 

Rule 4702 -

Reciprocating 

Internal Combustion 

Engines

4

th Q – 2010

Anticipate

d August 

2011

Most current revision 

of rule approved: 

January 18, 2007 at 

73 FR 1819 (January 

10, 2008)

S-COM-7 4354 - Glass Melting 

Furnaces 3

rd Q - 2008 76 FR 37044, June 24, 

2011

S-COM-9 4902 - Residential 

Water Heaters 1

st Q – 2009 March 2009 75 FR 24408 (May 5, 

2010)

S-COM-10 

4905 - Natural GasFired, Fan Type 

Residential Central 

Furnaces

4

nd Q – 2014 TBD

Most current revision 

of rule approved: 

October 20, 2005 at 

72 FR 29886 (May 30, 

2007)

S-COM-14 4901 - Wood Burning 

Fireplaces and Wood 

3

rd Q – 2009 October 

2008

Approved 

74 FR 57907 (November 

10, 2009)
35

Burning Heaters

S-IND-9 4692 - Commercial 

Charbroiling 2

nd Q – 2009 September 

2009

Proposed approval 

signed: June 9, 2011

S-IND-21 4311 – Flares 2

nd Q – 2009 June 2009 Action pending

M-TRAN-1 

9410 - Employer Based 

Trip Reduction 

Program

4

th Q – 2009 December 

2009 Action pending

Source: 2008 PM2.5 Plan, Table 6-2, revised June 17, 2010. 

Anticipated adoption date for Rule 4702, SJVAPCD, District 

Highlights, June 16, 2011 Actions by the District Governing 

Board.

Table 3

San Joaquin Valley Air Pollution Control District 

2008 PM2.5 Plan Aggregate Emissions Reductions Commitments

(tons per average annual day)

2009 2010 2011 2012 2013 2014

NOx 2.43 3.24 4.26 8.56 8.82 8.97

Direct 

PM2.5

1.60 2.96 4.46 6.69 6.70 6.70

SO2 0.06 0.11 0.16 0.92 0.92 0.92

Table 4

San Joaquin Valley Air Pollution Control District 

Aggregate Creditable Emissions Reductions from Adopted Rules

(tons per average annual day)

2009 2012 2014

NOx 2.4 10.2 11.4

Direct PM2.5 1.6 4.3 4.3

SO2 0.1 3.5 3.6

Source: SJVUAPCD, “Table 3-1 Adjusted PM2.5 Emission Inventory; 

Table 3-2 Adjusted NOx Emission Inventory; and Table 3-3 Adjusted 

SOx Emission Inventory,” March 2011 and TSD, Table F-4.

b. CARB’s RACM Analysis and Adopted Control Strategy

Source categories for which CARB has primary responsibility 

for reducing emissions in California include most new and 
36

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

fuels, and consumer products.

Given the need for significant emissions reductions from 

mobile and area sources to meet the NAAQS in California 

nonattainment areas, the State of California has been a leader 

in the development of stringent control measures for on-road and 

off-road mobile sources and the fuels that power them. 

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’s emissions standards have reduced new car 

emissions by 99 percent and new truck emissions by 90 percent 

from uncontrolled levels. 2007 State Strategy, p. 37. The State 

is also working with EPA on goods movement activities and is 

implementing programs to reduce emissions from ship auxiliary 

engines, locomotives, harbor craft and new cargo handling 

equipment. In addition, the State has standards for lawn and 

garden equipment, recreational vehicles and boats, and other 

off-road sources that require newly manufactured equipment to be 

80-98 percent cleaner than their uncontrolled counterparts. Id.

Finally, the State has adopted many measures that focus on 

achieving reductions from in-use mobile sources that include 

more stringent inspection and maintenance requirements in 
37

California’s Smog Check program, truck and bus idling 

restrictions, and various incentive programs. Appendix A of the 

TSD includes a list of all measures adopted by CARB between 1990 

and the beginning of 2007. These measures, reductions from which 

are reflected in the Plan’s baseline inventories, fall into two 

categories: measures that are subject to a waiver of Federal 

pre-emption under CAA section 209 (section 209 waiver measures 

or waiver measures) and those for which the State is not 

required to obtain a waiver (non-waiver measures). Emissions 

reductions from waiver measures are fully creditable in 

attainment and RFP demonstrations and may be used to meet other 

CAA requirements, such as contingency measures. See section 

II.F.4.a.i. of the TSD and EPA’s proposed approval of the SJV 1-

Hour Ozone Plan at 74 FR 33933, 33938 (July 14, 2009) and final 

approval at 75 FR 10420 (March 8, 2010). Generally, the State’s 

baseline non-waiver measures have been approved by EPA into the 

SIP and are fully creditable for meeting CAA requirements. See 

TSD Appendix A.

CARB developed its proposed 2007 State Strategy after an 

extensive public consultation process to identify potential SIP 

measures. This process is described in the 2008 PM2.5 Plan at p. 

7-11.14 Through this process, CARB identified and has committed 

 

14 More information on this public process including 

presentations from the workshops and symposium that proceeded 
38

to propose 15 new defined measures. These measures focus on 

cleaning up the in-use fleet as well as increasing the 

stringency of emissions standards for a number of engine 

categories, fuels, and consumer products. They build on CARB’s 

already comprehensive program described above that addresses 

emissions from all types of mobile sources through both 

regulations and incentive programs. See Appendix A of the TSD. 

Table 5 lists the defined measures in the 2007 State Strategy 

that contribute to attainment of the PM2.5 standards in the SJV 

and their current adoption and approval status. Table 6 provides 

the State’s current estimate of the emissions reductions in the 

SJV from these measures.

Table 5

2007 State Strategy Defined Measures Schedule for

Consideration and Current Status

State Measures

Expected 

Action 

Year

Current Status

Defined Measures in 2007 State Strategy

Smog Check 

Improvements 2007-2009 Elements approved 75 FR 38023 (July 1, 2010)15

Expanded Vehicle 2007 Adopted by CARB, June 2009; by 

 

adoption of the 2007 State Strategy can be found at 

www.arb.ca.gov/planning/sip/2007sip/2007sip.htm.

15 California Assembly Bill 2289, passed in 2010, requires 

the Bureau of Automotive Repair to direct older vehicles to high 

performing auto technicians and test stations for inspection and 

certification effective 2013. Reductions shown for the SmogCheck 

program in the 2011 Progress Report do not include reductions 

from AB 2289 improvements. CARB Progress Report supplement, 

attachment 5.
39

Table 5

2007 State Strategy Defined Measures Schedule for

Consideration and Current Status

State Measures

Expected 

Action 

Year

Current Status

Retirement (AB 118) BAR, September 2010.

Modification to 

Reformulated 

Gasoline Program

2007 Approved, 75 FR 26653 (May 12, 

2010)

Cleaner In-Use 

Heavy Duty Trucks 2008 Proposed approval signed: June 

29, 2011

Accelerated 

Introduction of 

Cleaner Locomotives

2008

Prop 1B bond funds awarded to 

upgrade line-haul locomotive 

engines not already accounted 

for by enforceable agreements 

with the railroads. Those 

cleaner line-hauls will begin 

operation by 2012.

Cleaner In-Use OffRoad Engines2007, 

2010 Waiver action pending. 

Cleaner In-Use 

Agricultural 

Equipment

2009 Incentive program in progress. 

No credit taken.

New Emissions 

Standards for 

Recreational Boats

2013 Partial adoption, July 2008, 

Additional action expected 2013.

Source: 2009 State Strategy Update, p.4 and 2011 Progress 

Report, Table 1. Additional information from www.ca.arb.gov. 

Only defined measures with direct PM2.5 or NOx reductions in the 

SJV are shown here.

Table 6

Expected Emissions Reductions from Defined Measures in the 

2011 Progress Report for the San Joaquin Valley

(tons per day 2014)

State Measure Direct 

PM2.5

NOx

Smog Check Improvements (BAR) 0.1 0.7

Expanded Vehicle Retirement -- --

Cleaner In-Use Heavy-Duty Trucks 1.7 1.1
40

Table 6

Expected Emissions Reductions from Defined Measures in the 

2011 Progress Report for the San Joaquin Valley

(tons per day 2014)

State Measure Direct 

PM2.5

NOx

Accelerated Intro. Of Cleaner 

Line-Haul Locomotives 0.0 0.0

Cleaner In-Use Off-Road Equipment 

(>25hp) 0.0 0.3

Source: 2011 Progress Report, p. 18. Only defined measures 

with direct PM2.5 or NOx reductions in the SJV are shown here.

In addition to the State’s commitment to propose defined 

new measures, the 2007 State Strategy includes an enforceable 

commitment for emissions reductions sufficient, in combination 

with existing measures and the District’s commitments, to attain 

the PM2.5 NAAQS in the San Joaquin Valley by the requested 

attainment date of April 5, 2015. For the SJV, these emissions 

reductions commitments were to achieve 5 tpd of direct PM2.5 and 

76 tpd of NOx in the SJV by the attainment year of 2014. See 2007 

State Strategy, p. 63 and CARB Resolution 07-28, Attachment B, 

p. 6. The nature of this commitment is described in the State 

Strategy as follows:

“The total emission reductions from the new measures 

necessary to attain the federal standards are an 

enforceable State commitment in the SIP. While the 

proposed State Strategy includes estimates of the 

emission reductions from each of the individual new 

measures, it is important to note that the commitment of 
41

the State Strategy is to achieve the total emission 

reductions necessary to attain the federal standards, 

which would be the aggregate of all existing and proposed 

new measures combined. Therefore, if a particular measure 

does not get its expected emission reductions, the State 

still commits to achieving the total aggregate emission 

reductions, whether this is realized through additional 

reductions from the new measures or from alternative 

control measures or incentive programs. If actual 

emission decreases occur in any air basin for which 

emission reduction commitments have been made that are 

greater than the projected emissions reductions from the 

adopted measures in the State Strategy, the actual 

emission decreases may be counted toward meeting ARB’s 

total emission reduction commitments.”

CARB Resolution 07-28 (September 27, 2007), Appendix B, p. 3.

c. The Local Jurisdictions’ RACM Analysis

The local jurisdictions’ RACM analysis was conducted by the 

SJV’s eight MPOs.16 This analysis focused on potential NOx

 

16 These eight MPOs represent the eight counties in the San 

Joaquin Valley nonattainment area: the San Joaquin Council of 

Governments, the Stanislaus Council of Governments, the Merced 

County Association of Governments, the Madera County 

Transportation Commission, the Council of Fresno County 

Governments, Kings County Association of Governments, the Tulare 
42

emissions reductions from transportation control measures (TCM). 

TCMs are, in general, measures designed to reduce emissions from 

on-road motor vehicles through reductions in vehicle miles 

traveled or traffic congestion. The results of the analysis are 

described in Chapter 7 (pp. 7-8 to 7-11) of the 2008 PM2.5 Plan. 

It addressed NOx but not direct PM2.5, SO2, or VOC.

For the 2008 PM2.5 Plan, the SJV MPOs reviewed and updated 

the RACM analysis they performed for the SJV 2007 [8-hour] Ozone 

Plan, based on EPA’s guidance in the preamble to the PM2.5

implementation rule. For the 2007 Ozone Plan, they developed a 

local RACM strategy after an extensive evaluation of potential 

RACM for advancing the 8-hour ozone standard attainment date. 

After reviewing the 2007 Ozone Plan’s local RACM analysis, EPA’s 

suggested RACM, recently developed plans from other areas, and 

the potential emission reductions available from the 

implementation of TCMs in the SJV, the MPOs determined that 

there were no additional local RACM for NOx, beyond those 

measures already adopted, that could advance attainment of the 

PM2.5 NAAQS in the SJV. 2008 PM2.5 Plan, p. 7-11.

3. Proposed Actions on RACM/RACT Demonstration and Adopted 

Control Strategy

 

County Association of Governments and the Kern Council of 

Governments.
43

We propose to find that there are, at this time, no 

additional reasonably available measures that individually or 

collectively would advance attainment of the PM2.5 NAAQS in the 

San Joaquin Valley nonattainment area by one year or more. This 

proposal is based on our review of potential RACM/RACT in the 

2008 PM2.5 Plan and updated and revised 2007 State Strategy; the 

District’s and State’s adopted control strategies, including 

their commitments to adopt measures and their progress in 

meeting those commitments; and our proposed concurrence 

(discussed below in section V.C.3.) with the State’s 

determination that SOx and NOx are and VOC and ammonia are not 

attainment plan precursors per 40 CFR § 51.1002(c).Therefore, we 

propose to find that the 2008 PM2.5 Plan, together with the 

updated and revised 2007 State Strategy, provides for the 

implementation of RACM/RACT as required by CAA section 172(c)(1) 

and 40 CFR § 51.1010.

We are also proposing to approve, with the exception of the 

commitment to revise Rule 4702, “Reciprocating Internal 

Combustion Engines,” the District's commitments to adopt and 

implement specific control measures on the schedule identified 

in Table 6-2 (as amended June 15, 2010) in the 2008 PM2.5 Plan, 

to the extent that these commitments have not yet been 

fulfilled, and to achieve specific aggregate emissions 

reductions of direct PM2.5, NOx and SOx by specific years as given 
44

in Table 6-3 of the 2008 PM2.5 Plan. The District had committed

to revise Rule 4702 by December 2010, but now expects adoption 

to occur in August 2011. Because EPA is subject to a consent 

decree requiring that we approve or disapprove all elements of 

the SJV 2008 PM2.5 Plan by no later than September 30, 2011,17 we 

are proposing to disapprove this element of the Plan; however, 

we will not need to finalize this proposed disapproval if the 

District adopts revisions to the rule that fulfill the 

commitment by the time of EPA’s final action on the Plan. We 

note that the District's decision to include the commitment to 

revise this rule in its Plan was discretionary and that the Plan 

does not specifically rely upon emission reductions from this 

particular rule. Adoption of revisions to Rule 4702 is now 

expected in August 2011.

We are also proposing to approve CARB's commitments to 

propose certain defined measures, as given in Table B-1 in 2011 

Progress Report, Appendix B and to achieve the total aggregate 

emissions reductions necessary to attain the 1997 PM2.5 standards 

in the SJV, whether these reductions are realized from the new 

measures, alternative control measures, incentive programs, or 

other actual emissions decreases. See CARB Resolution 07-28 

(September 27, 2007), Appendix B, p. 3. This commitment is to 

 

17 See Association of Irritated Residents v. U.S. EPA, Case 

No. 3:10-CV-03051-WHA, Consent Decree dated January 12, 2011.
45

aggregate emissions reductions of 5 tpd direct PM2.5 and 76 tpd 

NOx in the San Joaquin Valley by 2014 as given on page 21 of the 

2009 State Strategy Status Report.

C. Attainment Demonstration 

1. Requirements for Attainment Demonstrations

CAA section 172 requires a State to submit a plan for each 

of its nonattainment areas that demonstrates attainment of the 

applicable ambient air quality standard as expeditiously as 

practicable but no later than the specified attainment date. 

Under the PM2.5 implementation rule, this demonstration should 

consist of four parts:

(1) technical analyses that locate, identify, and quantify 

sources of emissions that are contributing to violations of the 

PM2.5 NAAQS; 

(2) analyses of future year emissions reductions and air 

quality improvement resulting from already-adopted national, 

state, and local programs and from potential new state and local 

measures to meet the RACM/RACT and RFP requirements in the area; 

(3) adopted emissions reduction measures with schedules for 

implementation; and 

(4) contingency measures required under section 172(c)(9) 

of the CAA.

See 40 CFR § 51.1007; 72 FR 20586 at 20605.
46

The requirements for the first two parts are described in 

the sections on emissions inventories and RACM/RACT above 

(sections V.A. and V.B.) and in the sections on air quality 

modeling, PM2.5 precursors, extension of the attainment date, and 

attainment demonstration that follow immediately below. 

Requirements for the third and fourth parts are described in the 

sections on the control strategy and contingency measures 

(sections V.B. and V.F.), respectively.

2. Air Quality Modeling in the SJV 2008 PM2.5 Plan

The PM2.5 implementation rule requires states to submit an 

attainment demonstration based on modeling results. 

Specifically, 40 CFR § 51.1007(a) states:

For any area designated as nonattainment for the PM2.5

NAAQS, the State must submit an attainment demonstration 

showing that the area will attain the annual and 24-hour 

standards as expeditiously as practicable. The 

demonstration must meet the requirements of § 51.112 and 

Appendix W of this part and must include inventory data, 

modeling results, and emission reduction analyses on which 

the State has based its projected attainment date. The 

attainment date justified by the demonstration must be 

consistent with the requirements of § 51.1004(a). The 

modeled strategies must be consistent with requirements in 

§ 51.1009 for RFP and in § 51.1010 for RACT and RACM. The 
47

attainment demonstration and supporting air quality 

modeling should be consistent with EPA’s PM2.5 modeling 

guidance.18

See also, 72 FR 20586 at 20665.

Air quality modeling is used to establish emissions 

attainment targets, the combination of emissions of PM2.5 and 

PM2.5 precursors that the area can accommodate without exceeding 

the NAAQS, and to assess whether the proposed control strategy 

will result in attainment of the NAAQS. Air quality modeling is 

performed for a base year and compared to air quality monitoring 

data in order to evaluate model performance. Once the 

performance is determined to be acceptable, future year changes 

to the emissions inventory are simulated to determine the 

relationship between emissions reductions and changes in ambient 

air quality throughout the air basin. The procedures for 

modeling PM2.5 as part of an attainment SIP are contained in 

EPA's “Guidance on the Use of Models and Other Analyses for 

Demonstrating Attainment of Air Quality Goals for the 8-Hour 

Ozone and PM2.5 NAAQS and Regional Haze” (Guidance).

 

18 EPA’s modeling guidance can be found in “Guideline on 

Air Quality Models” in 40 CFR part 51, Appendix W and “Guidance 

on the Use of Models and Other Analyses for Demonstrating 

Attainment of Air Quality Goals for the 8-Hour Ozone and PM2.5

NAAQS and Regional Haze”, EPA-454/B-07-002, April 2007.
48

The air quality modeling that underpins the SJV 2008 PM2.5

Plan is described in Chapter 3 and documented in Appendices E-H 

and the several additional appendices submitted with the Plan in 

2008. CARB supplemented this documentation in 2011. See Letter, 

John DaMassa, CARB to Frances Wicher, EPA, January 28, 2011

(CARB modeling supplement).

We provide a brief description of the modeling and a 

summary of our evaluation of it below. More detailed information

about the modeling and our evaluation are available in section 

II.D. of the TSD.

CARB and the District jointly performed the air quality 

modeling for the 2008 PM2.5 Plan. Significant time, money, and 

effort by CARB, the District, and many others have gone into 

preparing the air quality modeling to support the attainment 

demonstration in the 2008 PM2.5 Plan for the San Joaquin Valley, 

including support for the multi-million dollar California 

Regional Particulate Air Quality Study (CRPAQS). CRPAQS is a 

cooperative effort involving California cities, State and local 

and air pollution control agencies, federal agencies, industry 

groups, academics, and contractors. Field data for CRPAQS were 

collected during the 14 months from December 1999 through 

February 2001 and included short-term, intensive monitoring 

during the fall and winter. The study’s design placed emphasis 

on collecting sufficient continuous air quality and 
49

meteorological data, both at the surface and aloft, to support 

receptor and photochemical modeling. Data and modeling results 

based on the CRPAQS study provided solid underpinnings for the

2008 PM2.5 Plan.

The 2008 PM2.5 Plan uses multiple modeling analyses to 

demonstrate attainment of the PM2.5 NAAQS in the SJV. The 

narrative mainly relies on several variants of an approach based 

on receptor modeling for the annual PM2.5 NAAQS, but 

photochemical modeling is also included. The receptor modeling 

approach begins with Chemical Mass Balance (CMB) modeling, which 

distinguishes the ambient PM2.5 contributions of several broad 

emissions source categories based on how they match the chemical 

species components of PM2.5 measurements. The CMB results are 

then refined with emissions inventory data to distinguish 

additional source categories; an area of influence analysis to 

better reflect particular sources affecting a monitor; and 

information from past photochemical modeling to assess how 

secondarily-formed PM2.5 will respond to changes in precursor 

emissions. Several variants of this approach were used with CMB 

results from different locations and different base case years. 

This modeling only addresses the annual PM2.5 standard.

The Plan also includes an attainment demonstration using 

photochemical modeling with the Community Multiscale Air Quality 

(CMAQ) model. This modeling incorporates data collected during 
50

CRPAQS and addresses both the annual and 24-hour PM2.5 standards. 

Under EPA modeling guidance, this is considered the main 

attainment demonstration, with the receptor modeling as a 

corroborating analysis. Guidance, p.4 and p.103.

EPA recommends that States prepare modeling protocols as 

part of their modeled attainment demonstrations. Guidance, p. 

133. The Guidance at pp. 133-134 describes the topics to be 

addressed in this modeling protocol. A modeling protocol should 

detail and formalize the procedures for conducting all phases of 

the modeling analysis, such as describing the background and 

objectives, creating a schedule and organizational structure, 

developing the input data, conducting model performance 

evaluations, interpreting modeling results, describing 

procedures for using the model to demonstrate whether proposed 

strategies are sufficient to attain the NAAQS, and producing 

documentation to be submitted for EPA Regional Office review and 

approval prior to actual modeling.

The 2008 PM2.5 Plan’s modeling protocol is contained in 

Appendix F and includes descriptions of both the receptor 

modeling approaches and the photochemical modeling. Additional 

description of the photochemical modeling is covered in Appendix 

G, and also in the additional appendix entitled “Regional Model 

Performance Analysis” (RMPA). The protocol covers all of the 

topics recommended in the Guidance, except that it does not 
51

identify how modeling and other analyses will be archived or 

made available to the public. See Guidance, p. 117.

The 2008 PM2.5 Plan’s air quality model performance is 

discussed in the RMPA, starting at p. 6, and also more 

extensively in the CARB modeling supplement. In the Plan as 

submitted in 2008, modeling performance was not sufficiently 

documented for EPA to fully evaluate it, but CARB’s modeling 

supplement provides an extensive statistical and graphical 

analysis demonstrating adequate model performance. The 

supplement included discussion of the evaluation results and 

also of sensitivity or diagnostic testing, both of which are 

necessary for confidence in the model and the performance 

statistics presented. The testing described by CARB provides 

assurance that the model is adequately simulating the physical 

and chemical processes leading to PM2.5 in the atmosphere and 

that the model responds in a scientifically reasonable way to 

emissions changes.

The Plan as submitted in 2008 provided insufficient 

documentation about the deviations from EPA’s guidance on 

performing the Speciated Modeled Attainment Test (SMAT); again 

the CARB modeling supplement provides a reasonable rationale for 

the deviations, about which EPA’s Office of Air Quality Planning 

and Standards was consulted. The Plan cites several factors as 

justifying such deviations (e.g., the prevalence of ammonia, the 
52

dominance of ammonium nitrate, the effect of substantial 

controls on fugitive dust and direct carbon emissions (p. G-10 

and p. 3-20)), and the CARB modeling supplement provides 

documentation on accounting for evaporation of the ammonium ion. 

The CARB modeling supplement also provides extensive 

documentation on the Relative Reduction Factors, which are the 

key results from the model for use in the attainment test, and 

the details of their calculation, which were not presented in 

the 2008 PM2.5 Plan as originally submitted. EPA proposes to 

conclude that the attainment tests are adequate and consistent 

with EPA guidance.

In addition to a modeled attainment demonstration, which 

focuses on locations with an air quality monitor, EPA generally

requires an unmonitored area analysis. This analysis is intended 

to ensure that a control strategy leads to reductions in PM2.5 at 

other locations that have no monitor but that might have 

baseline (and future) ambient PM2.5 levels exceeding the NAAQS. 

The unmonitored area analysis uses a combination of model output 

and ambient data to identify areas that might exceed the NAAQS 

if monitors were located there. The analysis should include, at 

a minimum, all counties designated nonattainment and the 

counties surrounding the nonattainment area. In order to examine 

unmonitored areas in all portions of the modeling domain, EPA 
53

recommends use of interpolated spatial fields of ambient data 

combined with gridded modeled outputs. Guidance, p. 29.

The section in the 2008 PM2.5 Plan entitled “Unmonitored 

peaks” presents an abbreviated simple screening analysis, 

consisting of a filled concentration contour plot (Figure 3 on 

p. G-20), and the observation that “there are no areas with 

steep gradients that would result in higher design values than 

those measured at monitors.” 2008 PM2.5 Plan, p. G-15. This 

analysis departs significantly from the procedures recommended 

in the Guidance. However, the CARB modeling supplement documents 

a subsequent unmonitored area analysis that uses procedures 

recommended in the Guidance, including use of EPA’s MATS 

software, and concludes that there are no unmonitored PM2.5 peaks 

in the modeling domain that would violate the annual PM2.5 NAAQS. 

In summary, despite shortcomings in the documentation 

within the 2008 PM2.5 Plan as submitted in 2008, the CARB 

modeling supplement enables EPA to conclude that the modeling

supporting the Plan is sound. EPA proposes to approve the air 

quality modeling and to find that the modeling provides an 

adequate basis for the RACM/RACT, RFP, and attainment 

demonstrations in the Plan.

Effect of Inventory Changes on the Air Quality Modeling and 

Attainment Demonstrations
54

As discussed above in section V.A., CARB has recently 

updated the inventories for several mobile source categories for 

both the base and future years as well as revised the economic 

forecasts on which the future inventories were based. Relative 

to emissions in the Plan, the decreases in the base year 2005 

emissions inventory due to the inventory updates are about 6 

percent for NOx and 5 percent for direct PM2.5 emissions; the 

2014 attainment year target emissions levels are unchanged. CARB 

Progress Report supplement, Attachment 1. EPA believes that 

these base year emission changes are small enough to be 

relatively minor in the context of the overall uncertainties in 

inventories and in photochemical modeling itself, and that the 

base case modeling remains valid. However, EPA assessed how 

these emission inventory changes would be expected to affect the 

attainment demonstration, which relies on emission reductions 

between the base year and the 2014 attainment target year. The 

emissions decreases in the base year tend to reduce the relative 

effect of controls, and to increase the projected PM2.5

concentrations in the attainment year. (This is because the base 

year ambient concentration is now known to result from a 

slightly lower level of emissions. The model must therefore be 

slightly under-predicting, and so the predicted attainment year 

concentration should be slightly higher to compensate.) To 

assess the effect of the inventory changes on the attainment 
55

demonstration, EPA used model sensitivity results in the 2011 

Progress Report supplement, Attachment 3. Taking into account 

the model’s sensitivity to the inventory changes, EPA estimates 

that predicted ambient concentrations in the 2014 attainment 

year would be higher by only about 2.5 percent due to the 

emission inventory revisions, and that predicted design values

for 2014 remain below the PM2.5 NAAQS. EPA therefore proposes to 

find that the attainment demonstration remains valid, despite 

the emission inventory changes.

Pollutant Ratios Used to Determine PM2.5 Equivalency

The 2011 Progress Report and the 2011 SJV Progress Report 

use a PM2.5 equivalency metric in a number of tables and 

demonstrations. Two ratios are used: 

9 tpd NOx to 1 tpd direct PM2.5

1 tpd SOx to 1 tpd direct PM2.5

The NOx:PM2.5 ratio is documented in supplemental information 

provided by CARB, entitled “Precursor Effectiveness,” which is 

available in the docket for this proposed rulemaking. In two 

separate runs of the CMAQ modeling application used for the 

attainment demonstration, CARB simulated an additional 10 

percent reduction in modeling domain NOx emissions and in direct 

PM2.5 emissions. These PM2.5 effects were divided by the emissions 

totals for each pollutant to give a concentration change per 

emissions change, or effectiveness, for each pollutant. This 
56

effectiveness shows the reduction of precursor emissions needed 

for a given concentration change, and so can be used to estimate 

an interpollutant equivalence ratio, the amount of one precursor 

that is equivalent to the other in terms of the effect on 

ambient concentrations of PM2.5. The direct PM2.5 effectiveness 

was divided by the NOx effectiveness to arrive at a NOx:PM2.5

ratio for each monitor; the average of these is about 9. This 

method appears to be adequate for purposes of assessing the 

effect of area-wide emissions changes, such as are used in RFP, 

contingency measures, and conformity budgets, and EPA is 

proposing to allow its use here.19

 

19 EPA is proposing to approve the use of this NOx to PM2.5

interpollutant trading ratio to meet CAA planning requirements 

for the 1997 PM2.5 standards in the SJV. EPA is also proposing to

approve the use of this ratio in transportation conformity 

determinations for the 2006 24-hour PM2.5 NAAQS but only until 

such time as EPA finds adequate or approves budgets developed 

specifically for the 2006 standard. EPA is not proposing, at 

this time, to approve the use of this ratio in plans for future 

PM standards or in the District’s new source review (NSR) 

permitting program.

The District recently submitted revisions to its NSR rule, 

Rule 2201, which require that interpollutant trading ratios used 

for purposes of satisfying PM2.5 NSR offset requirements first be 

approved by EPA into the SIP. See Rule 2201 (April 21, 2011), 

section 4.13.3.2. The Rule 2201 submittal also states that the 

District intends to submit SJV-specific PM2.5 interpollutant 

trading ratios for EPA’s approval in a future SIP revision but 

will, in the interim, require project proponents to use the 

default ratios provided in the preamble to EPA’s PM2.5 NSR rule 

(73 FR 28321 at 28339 (May 16, 2008)), until alternative trading 

ratios are approved by EPA into the SIP. See SJVAPCD, Final 

Draft Staff Report, Proposed Amendments to Rule 2201 (New And 

Modified Stationary Source Review Rule), March 17, 2011, p. 4.
57

The SOx:PM2.5 ratio is documented in supplemental information 

provided by the District which is available in the docket for 

this proposed rulemaking. See “Atmospheric Interpollutant 

Equivalency between Direct Particulate Emissions and Secondary 

Particulate Formed from Gaseous Sulfur Oxide Emissions”; the 

spreadsheet “Interpollutant Calculation”; and letter dated May 

27, 2009 from David Warner, San Joaquin Valley Air Pollution 

Control District to Mr. Joseph Douglas, California Energy 

Commission, Attachment II, “Interpollutant Offset Ratio 

Explanation.” After reviewing this documentation, EPA does not 

agree with the method used to develop the ratio. 

The approach used by the District to estimate interpollutant equivalency ratios rests on the incorrect assumption 

that ambient sensitivity to emissions reductions of a given 

precursor can be estimated as the ratio of concentration to 

emissions. This is the assumption of linear “rollback”, and 

inherently cannot address the complexities of PM2.5 formation 

chemistry, which is nonlinear. It is in contrast to the State’s 

approach for the NOx:PM2.5 ratio which used photochemical modeling 

results to take into account such nonlinearity. EPA’s evaluation 

of the SOx:PM2.5 approach is discussed in greater detail in 

section II.B.4. of the TSD. 

EPA is proposing to not allow the use of this SOx to PM2.5

interpollutant trading ratio at this time to meet any CAA 
58

planning requirements for the 1997 PM2.5 standards in the SJV. We 

note that the State had proposed the use of this ratio to meet 

only the CAA requirement for contingency measures. See section 

V.E. below.

3. PM2.5 Attainment Plan Precursors Addressed in the SJV 

2008 PM2.5 SIP

EPA recognizes NOx, SO2, VOC, and ammonia as the main 

precursor gases associated with the formation of secondary PM2.5

in the ambient air. These gas-phase PM2.5 precursors undergo 

chemical reactions in the atmosphere to form secondary 

particulate matter. Formation of secondary PM2.5 depends on 

numerous factors including the concentrations of precursors; the 

concentrations of other gaseous reactive species; atmospheric 

conditions including solar radiation, temperature, and relative 

humidity; and the interactions of precursors with preexisting 

particles and with cloud or fog droplets. 72 FR 20586 at 20589.

As discussed previously, a state must submit emissions 

inventories for each of the four PM2.5 precursor pollutants. 72 

FR 20586 at 20589 and 40 CFR § 51.1008(a)(1). However, the 

overall contribution of different precursors to PM2.5 formation 

and the effectiveness of alternative potential control measures 

will vary by area. Thus, the precursors that a state should 
59

regulate to attain the PM2.5 NAAQS can also vary to some extent 

from area to area. 72 FR 20586 at 20589.

In the PM2.5 implementation rule, EPA did not require that 

all potential PM2.5 precursors must be controlled in each 

specific nonattainment area. See 72 FR 20586 at 20589. Instead, 

for reasons explained in the rule’s preamble, a state must 

evaluate control measures for sources of SO2 in addition to 

sources of direct PM2.5 in all nonattainment areas. 40 CFR § 

51.1002(c) and (c)(1). A state must also evaluate control 

measures for sources of NOx unless the state and/or EPA determine 

that control of NOx emissions would not significantly reduce PM2.5

concentrations in the specific nonattainment area. 40 CFR § 

51.1002(c)(2). In contrast, EPA has determined in the PM2.5

implementation rule that a state does not need to address 

controls for sources of VOC and ammonia unless the state and/or 

EPA make a technical demonstration that such controls would 

significantly contribute to reducing PM2.5 concentrations in the 

specific nonattainment area at issue. 40 CFR § 51.1002(c)(3) and 

(4). Such a demonstration is required “if the administrative 

record related to development of its SIP shows that the 

presumption is not technically justified for that area.” 40 CFR 

§ 51.1002(c)(5).

“Significantly contributes” in this context means that a 

significant reduction in emissions of the precursor from sources 
60

in the area would be projected to provide a significant 

reduction in PM2.5 concentrations in the area. 72 FR 20586 at 

20590. Although EPA did not establish a quantitative test for 

determining what constitutes a significant change, EPA noted 

that even relatively small reductions in PM2.5 levels are 

estimated to result in worthwhile public health benefits. Id.

EPA further explained that a technical demonstration to 

reverse the presumption for NOx, VOC, or ammonia in any area 

could consider the emissions inventory, speciation data, 

modeling information, or other special studies such as 

monitoring of additional compounds, receptor modeling, or 

special monitoring studies. 72 FR 20586 at 20596-20597. These 

factors could indicate that the emissions or ambient 

concentration contributions of a precursor, or the sensitivity 

of ambient concentrations to changes in precursor emissions, 

differs for a specific nonattainment area from the presumption

EPA established for that precursor in the PM2.5 implementation 

rule.

The SJV 2008 PM2.5 Plan does not explicitly identify the 

pollutants that have been selected as PM2.5 attainment plan 

precursors as defined in 40 CFR § 51.1000. The Plan addresses NOx

and SO2 in the RFP and attainment demonstrations and in the 

District’s RACM/RACT analysis, and thereby implicitly identifies 

NOx and SO2 as attainment plan precursors. The Plan also includes 
61

supporting documentation for the inclusion of NOx as an 

attainment plan precursor and for the exclusion of ammonia. In 

our November 30, 2010 proposal, we noted that the Plan did not 

fully evaluate the impact of controlling VOC as a precursor for 

PM2.5 attainment and contained conflicting information on whether 

controlling VOC, in addition to SO2 and NOx, may contribute 

significantly to reductions in ambient PM2.5 levels in the SJV.

In 2011, however, CARB provided additional technical information 

supporting its position that VOC should not be considered a PM2.5

attainment plan precursor in the San Joaquin Valley. See letter, 

James Goldstene, CARB, to Frances Wicher, EPA, January 31, 2011, 

attachment 4 (CARB VOC supplement). We discuss below our 

evaluation of this additional technical information.

As mentioned above, ambient contribution and ambient 

sensitivity to emissions changes may both be considered in 

determining whether the presumption for an attainment plan 

precursor should be reversed. The 2008 PM2.5 Plan contains 

numerous qualitative statements that San Joaquin Valley’s 

ambient PM2.5 levels are dominated by ammonium nitrate, and that 

NOx reductions are more effective at reducing ambient PM2.5 than 

reductions in the other precursors. Most of those statements are 

in Chapter 3 and Appendix F, and are based on excerpts of 

findings from the California Regional Particulate Air Quality 

Study (CRPAQS). Several of the cited CRPAQS documents are 
62

available at CARB’s “Central California Air Quality Studies” web 

site (at http://www.arb.ca.gov/airways).

For the 1997 annual and 24-hour PM2.5 NAAQS, the 2008 PM2.5

Plan contains some qualitative descriptions of precursor ambient 

contributions. For example, the 2008 PM2.5 Plan states on p. 2-8 

that annual concentrations are driven by wintertime 

concentrations and further, that the highest short term 

concentrations are driven by ammonium nitrate, as found in the 

CRPAQS study:

For most of the sites within the SJV, 50–75% of the annual 

average PM2.5 concentration could be attributed to a high 

PM2.5 period occurring from November to January. At nonurban sites, the elevated PM2.5 was driven by secondary 

[ammonium nitrate].20

There are also quantitative data in the Plan’s Appendix G 

(p. G-21, Table 2) and, projected to 2014, in the Receptor 

Modeling Documentation (RMD). Ammonium nitrate for 2000 

monitored data ranges from 24-36 percent of total PM2.5, and if 

projected to 2014, ranges from 36-51 percent, confirming the 

importance of NOx, one source of the nitrate in ammonium nitrate, 

 

20 Quote from “Initial Data Analysis of Field Program 

Measurements,” DRI Document No. 2497, July 29, 2005; Judith C. 

Chow, L.W. Antony Chen, Douglas H. Lowenthal, Prakash 

Doraiswamy, Kihong Park, Steven D. Kohl, Dana L. Trimble, John 

G. Watson, Desert Research Institute.
63

as a precursor that significantly contributes to annual PM2.5

levels in the SJV.

In addition to composition data, ambient sensitivity to 

emissions changes can also be a consideration in determining 

which pollutants should be regulated in the attainment plan for 

a specific area. For ammonium nitrate PM2.5, which is formed from 

both ammonia and NOx, a key issue is whether the control of 

either or both precursors would be effective at reducing ambient 

PM2.5 concentrations. Among the findings cited in the 2008 PM2.5

Plan that address this issue are that:

Particulate [ammonium nitrate] concentrations are limited 

by the rate of [nitric acid] formation, rather than by the 

availability of [ammonia]. 

and 

Comparisons of ammonia and nitric acid concentrations show 

that ammonia is far more abundant than nitric acid, which 

indicates that ammonium nitrate formation is limited by the 

availability of nitric acid, rather than ammonia.... This 

study's analyses suggest that reductions in NOx emissions 

will be more effective in reducing secondary ammonium 

nitrate aerosol concentrations than reductions in ammonia 

emissions. Reductions in VOC emissions will reduce 

secondary organic aerosol concentrations and may reduce 

ammonium nitrate.... The results indicate ammonium nitrate 
64

formation is ultimately controlled by NOx emission rates and 

the other species, including VOCs and background ozone, 

which control the rate of NOx oxidation in winter, rather 

than by ammonia emissions.21

These findings are based on the relative abundance of 

ammonia relative to nitrate: there is so much ammonia present 

that significantly reducing its emissions would still leave 

ample ammonia to form ammonium nitrate. On the other hand, NOx is 

scarce (relative to ammonia), so reducing it could reduce 

ammonium nitrate significantly.

Finally, sensitivity results from photochemical modeling 

were used in conjunction with the CMB results mentioned above. 

The 2014 RMD section on “Review of control strategy 

effectiveness supported by CMAQ nitrate particulate evaluation” 

shows the projected effect of a 50 percent reduction of NOx

emissions on PM2.5 concentrations annually and in shorter 

seasonal episodes. For the annual concentration, the NOx

reduction resulted in a predicted 5 μg/m3 PM2.5 reduction, while 

for the winter episode the NOx reduction resulted in a predicted 

28 μg/m3 PM2.5 reduction. 2014 RMD, p. 80. A 50 percent reduction 

in ammonia emissions, on the other hand, predicted PM2.5

 

21 Quote from Lurmann, F. et. al., 2006, “Processes 

Influencing Secondary Aerosol Formation in the San Joaquin 

Valley During Winter,” Journal of the Air & Waste Management 

Association, (56): 1679-1693, cited at 2008 PM2.5 Plan p. 3-10.
65

reductions of only 0.1 μg/m3 on an annual basis and 0.3 μg/m3

during the winter episode. RMD, p. 81. When compared to the 

annual and 24-hour NAAQS of 15 and 65 μg/m3, respectively, the 

effect of NOx reductions appears to be significant while the 

effect of ammonia reductions does not. Thus, the data and 

modeling results presented in the 2008 PM2.5 Plan, as well as the 

results of the cited studies, support the inclusion of NOx and 

the exclusion of ammonia as PM2.5 attainment plan precursors, 

consistent with the EPA presumptions in the PM2.5 implementation 

rule.

EPA’s presumption in the PM2.5 implementation rule is that 

VOC need not be an attainment plan precursor. 40 CFR 

51.1002(c)(3). This presumptive policy for VOC is largely based 

on uncertainties regarding the role of VOC in secondary organic 

aerosol (SOA) formation and in photochemical reactions that lead 

to the formation of certain free radical compounds (such as the 

hydroxyl radical [OH]), which participate in the formation of 

nitrate PM2.5. See 72 FR 20586 at 20593 (April 25, 2007). As 

explained in the preamble to the rule, this presumption may not 

be technically justified for a particular nonattainment area, 

i.e., where emissions of VOC significantly contribute to PM2.5 

concentrations in the specific nonattainment area at issue. 72 

FR 20586 at 20590-93, 20596-97. States or EPA may conduct a 

technical demonstration to reverse the presumptive exclusion of 
66

VOC as a PM2.5 attainment plan precursor based on the weight of 

evidence of available technical and scientific information. Id.

We note that because the SJV is designated and classified 

as extreme nonattainment for the 8-hour ozone standard, VOC 

emission sources in this area are already subject to specific 

control requirements under subpart 2 of title I, part D of the 

Act. Nevertheless, EPA examined the available evidence on the 

effect of VOC reductions on ambient PM2.5 levels in the SJV, 

consistent with the PM2.5 implementation rule.

The 2008 PM2.5 Plan contains inconclusive information on 

whether VOC should be considered a PM2.5 attainment plan 

precursor for the SJV nonattainment area. On the one hand, some 

information in the Plan indicates that VOC reductions may 

contribute to reduced ambient PM2.5 levels in the area. Table 2 

in Appendix G (p. G-21) gives an organic carbon range of 38-49 

percent of the total PM2.5 on an annual basis. This includes a 

secondary organic aerosol (SOA) contribution of 2-5 percent of 

total annual PM2.5. RMD at 19. This SOA contribution to overall 

PM2.5 levels appears to be non-negligible, although it may not 

necessarily be significant. The 2008 PM2.5 Plan also states: 

“Secondary organic aerosols (SOA) contribute to a significant 

fraction of PM2.5. SOA is organic carbon particulate formed in 

the photochemical oxidation of anthropogenic and biogenic VOC 

precursor gases. Aromatic compounds are believed to be efficient 
67

SOA producers contributing to this secondary particulate.” 2008 

PM2.5 Plan, p.3-8. On a 24-hour episodic basis, the contribution 

of SOA could theoretically be higher than the annual 2-5 

percent, but SOA is formed mainly in the summer and so tends to 

be lower for the winter episodes of most concern in the SJV, due 

to decreased photochemical activity when the SJV winter’s fog 

and clouds partially block sunlight. The SOA contribution to 24-

hour PM2.5 is thus smaller than for annual PM2.5. Finally, the RMD 

at page 82 contains sensitivity analyses for VOC, similar to the 

ones described above for NOx and ammonia. The 2014 RMD concludes: 

“Finding: VOC reduction is effective for the annual standard and 

the winter episode for reduction of total carbon secondary 

particulates.” It is not clear whether this refers only to SOA

or to all secondary particulates including ammonium nitrate. The 

various statements above indicate VOC reductions may contribute 

to reducing ambient PM2.5 levels. 

On the other hand, some statements in the Plan indicate VOC 

should not be considered a PM2.5 attainment plan precursor. In 

response to comments on the VOC issue submitted during the 

District’s public comment period, the Plan states that the 

“modeling has shown that VOC reductions are not as effective in 

reducing secondary PM2.5 as NOx or SO2 reductions” and that “[a]ll 

of the technical evaluations for CRPAQS and prior assessments of 

regional particulate models have indicated that NOx is the 
68

dominant factor and VOC and ammonia are not.” 2008 PM2.5 Plan, 

pp.J-9 and p.J-19. These statements reflect the District’s 

conclusion that VOC should not be considered an attainment plan 

precursor. This conclusion was also later explicitly stated by 

CARB. CARB VOC supplement. In addition, CARB later clarified 

that statements in the Receptor Modeling Document (cited above)

were not intended to address the question of whether VOC should 

be a PM2.5 attainment plan precursor, and that the methodology 

used in the RMD does not substitute for actual photochemical 

modeling performed by CARB. (Personal communication, Karen 

Magliano, CARB, January 26, 2011.) As noted above, EPA agrees 

that the CMAQ photochemical modeling is the primary basis for 

the Plan’s attainment demonstration.

Given the later and more definitive statements against VOC 

as an attainment plan precursor, overall the evidence on SOA 

does not constitute a technical demonstration that VOC is a PM2.5

attainment plan precursor in the San Joaquin Valley, and does 

not overcome the negative presumption for VOC as a PM2.5

attainment plan precursor.

However, the Plan’s inconsistency on VOC as an attainment 

plan precursor applies not just to the SOA just discussed, but 

also to the indirect role of VOC, which also requires a 

conclusion on its precursor status. VOC may be a PM2.5 precursor 

not just via formation of SOA, but also via its participation in 
69

the oxidant chemistry that leads to nitrate formation, a 

necessary step in the formation of ammonium nitrate PM2.5. As 

noted in the preamble to the PM2.5 implementation rule at pp. 

20592 - 20593, the lightest organic molecules can participate in 

atmospheric chemistry processes that result in the formation of 

ozone and certain free radical compounds (such as the hydroxyl 

radical [OH]) and these in turn participate in oxidation 

reactions to form secondary organic aerosols, sulfates, and 

nitrates. NOx emissions must be oxidized to nitric acid before 

they form particulate ammonium nitrate. Two pathways for this

oxidation to occur are 1) daytime oxidation by OH, which VOC 

radicals help create and which could be affected by VOC 

controls, and 2) nighttime oxidation by ozone, which might not 

be affected by VOC controls in the area.

22

Some statements in the Plan seem to favor VOC as an 

attainment plan precursor in this indirect role. The discussion 

in the 2008 PM2.5 Plan regarding ammonium nitrate (at p. 3-10, 

quoted above) also refers to VOC, which is identified as one of 

the controlling factors in NOx oxidation (which leads to ammonium 

nitrate PM2.5): “Reductions in VOC emissions will reduce 

secondary organic aerosol concentrations and may reduce ammonium 

nitrate.” The Plan also states: “Relatively low non-methane 

organic compounds/nitrogen oxide ratios indicate the daytime 

 

22 Lurmann, F. et. al., 2006, op cit., p. 1688.
70

photochemistry is VOC, sunlight, and background-ozone limited in 

winter.” Id. Although these are only generic statements, if 

nitrate formation is VOC-limited under some circumstances, then 

VOC emissions reductions could lead to ambient PM2.5 reductions. 

On the other hand, in this same section, the Plan states that 

“entrainment of aerosol nitrate formed aloft at night may 

explain the spatial homogeneity of nitrate in the San Joaquin 

Valley”. Id. Since this nighttime pathway may not be VOClimited, overall it is not clear whether VOC reductions would be 

effective for reducing PM2.5.

Given the inconclusive statements about VOC in the Plan, 

EPA reviewed the results of several modeling and monitoring 

studies of PM2.5 in the San Joaquin Valley, and previously 

proposed a technical demonstration that VOC should be a plan 

precursor. See 75 F 74518, 74530. Some of the study documents 

EPA reviewed are available on the “Central California Air 

Quality Studies” web site (at www.arb.ca.gov/airways) and/or are 

cited in the Plan and are reports from contractors involved in 

CRPAQS. Others are papers from peer-reviewed journals and are 

analyses using CRPAQS data or data from the earlier 1995 

Integrated Monitoring Study (IMS95 study). We found that four 

monitoring studies and six modeling studies were relevant to the 

VOC precursor issue. A list of these studies as well as further 

information on them and excerpts from them are provided in 
71

section II.E. of the TSD. The monitoring studies all contain 

evidence that the VOC pathway for nitrate creation is important 

at least some of the time but differ as to how important it is 

relative to other pathways such as the nighttime ozone pathway, 

and are not conclusive on the efficacy of VOC controls. As noted 

above, the study by Lurmann et al., which is the most recent of 

the monitoring studies and which was quoted in the Plan, stated 

that the observed spatial homogeneity of ammonium nitrate could 

be explained by nighttime production aloft via the ozone 

pathway, followed by mixing down to the surface, as opposed to 

production during the day via the VOC pathway. As noted in the 

CARB VOC supplement, CARB technical staff involved in the CRPAQS 

work cite this study and agree with this conclusion.

Unlike the monitoring studies, most of the modeling studies 

explicitly assessed the relative effectiveness of precursor 

controls, simulating the effect of 50 percent reductions in NOx, 

ammonia, and VOC. (One study does not explicitly address the VOC 

reductions, but states that background ozone flowing in from 

outside the nonattainment area is the most important oxidant, so

that VOC controls in the SJV would have little effect.) The two 

earliest modeling studies are based on photochemical box 

modeling and differ on whether VOC controls would significantly 

affect PM2.5. Three later studies use more sophisticated 

photochemical grid models and find VOC control to be effective, 
72

though generally less so than NOx control. One study predicts VOC 

control to be about two-thirds as effective as NOx control. The 

second study predicted VOC control to be effective, though only 

by a relatively small amount, at most 10 percent for a 50

percent reduction in VOC emissions, or only on certain days. The 

third grid modeling study predicts VOC control to give slightly 

more benefit than NOx control. In our November 2010 proposal, EPA 

indicated that although the models, input data, and results 

differ among these studies, the studies indicated that control 

of VOC could significantly reduce PM2.5 concentrations in the 

SJV. 

In its VOC supplement, however, CARB provided additional 

interpretation of these same studies. CARB makes several points 

about the modeling studies that argue against VOC as an 

attainment plan precursor in the SJV, namely their 

unreasonableness for this assessment and the lack of benefits 

shown in some of them. On the first of these main points, CARB 

argues that the hypothetical 50 percent VOC reduction evaluated 

in the modeling studies is not a reasonable basis for assessing 

VOC as a plan precursor, for at least two reasons. Its first 

reason is that this amount of reductions may not be feasible, 

especially given the VOC reductions already undertaken as part 

of other plans, such as the ozone plan for the SJV area. EPA 

agrees that reasonable assumptions are important for an 
73

attainment plan precursor technical demonstration; however, 

without an assessment from the State of the feasibility of a 50 

percent VOC reduction, the model results cannot be dismissed on 

that basis. Indeed, an assessment of the feasible degree of VOC 

control in a RACM/RACT analysis would be required if VOC were 

considered an attainment plan precursor.23

The second reason offered in the CARB VOC supplement for 

why the modeled 50 VOC percent reduction may not be a reasonable 

basis for evaluation of VOC as an attainment plan precursor is 

that it considers VOC in isolation from the other PM2.5

precursors. CARB argues that because precursors interact in 

complex ways in the atmosphere, the expected effect of VOC 

controls should be evaluated in the context of the expected 

emission levels of the other precursors in the attainment 

demonstration. In particular, CARB notes that the existing NOx

control program will provide substantial NOx emission reductions, 

and this will affect the benefit of VOC controls. Thus, it 

argues that while the modeling studies’ VOC reduction results 

may be technically correct in themselves, they do not translate 

directly into measurable reductions in ambient PM2.5

concentrations per ton of VOC, nor do they support a need for 

 

23 See 72 FR 20586 at 20591 (“Assessments of which source 

categories are more cost effective or technically feasible to 

control should be part of the later RACT and RACM assessment, to 

occur after the basic assessment of which precursors are to be 

regulated is completed.”).
74

additional VOC controls in the PM2.5 control strategy. EPA agrees 

that the studies highlight a need to consider multiple precursor 

effects at once, in the context of what is needed for attainment 

in the target year, and that it makes sense to examine precursor 

interactions in assessing plan precursors.

Another main point made by CARB in its VOC supplement about 

the modeling studies is that the more sophisticated ones, based 

on photochemical grid modeling, tended to show small benefits 

and sometimes disbenefits24 from VOC controls in the more 

realistic scenarios modeled. CARB pointed out that when NOx

reductions are considered at the same time, two studies showed 

PM2.5 disbenefits from VOC reduction at multiple locations, 

though in one this occurred only at some times. (No similar 

disbenefit was seen for additional NOx reductions when they were 

considered simultaneously with VOC reductions.) Thus, under the 

realistic assumption that NOx reductions will occur as a result 

of the Plan control strategy, according to these studies 

additional VOC reductions could be counterproductive, making it 

 

24 VOC typically contributes to the formation of ozone and 

hydroxyl, which through its oxidizing effect can help convert NOx

emissions to particulate nitrate. However, there are also direct 

VOC-NOx interactions that act as a “sink”, forming e.g. 

peroxyaceytl nitrate (PAN), and removing both VOC and NOx from 

the photochemical reactions that lead to ozone and some 

particulate. Under some circumstances, VOC reductions can lessen 

the effect of this “sink”, so that more NOx remains to form 

particulate, resulting in a PM2.5 disbenefit from VOC control.
75

more difficult for the SJV to come into PM2.5 attainment. EPA 

agrees that these analyses raise legitimate questions about the 

efficacy of VOC reductions and do not support a reversal of the 

PM2.5 implementation rule’s presumption that VOC is not an 

attainment plan precursor.

Finally, CARB notes that one of the studies showed a 

benefit from VOC control only at the very highest PM2.5 levels, 

above 80 μg/m3, well above current design values in the SJV which 

are more in the range of 50 – 60 μg/m3. See CARB VOC supplement, 

p.10.25

Based on an examination of model output throughout the 

episode, CARB hypothesizes that a different chemical regime is 

entered at high levels, for which this VOC sensitivity does 

occur, though this hypothesis apparently has not been explored 

with modeling tools such as process analysis. CARB staff 

involved in the CRPAQS modeling effort believes that, under 

current SJV conditions, the nighttime nitrate production route 

via background ozone is the main oxidation driver for nitrate 

PM2.5 in the SJV, and that the VOC-sensitive daytime oxidant 

route is of less importance. CARB VOC supplement, p.10.

 

25 According to monitoring data in EPA's AQS database, 

there were 172 values over 80 μg/m3 during 1999-2002; by 

contrast, there were only 24 values over 80 during 2007-2010.

EPA's Air Quality System, Violation Day Count Report, May 13, 

2011.
76

After careful review, EPA is proposing to determine that 

the information submitted by CARB in the VOC supplement raises 

significant questions about the efficacy of VOC controls for

reducing ambient PM2.5 concentrations in the SJV and demonstrates 

that the available technical information does not provide a 

sufficient basis for reversing the presumption in the PM2.5 

implementation rule that VOC is not an attainment plan precursor

in this area. Accordingly, EPA proposes to concur with CARB’s 

determination that at this time, VOC should not be an attainment 

plan precursor in the SJV area.

26 EPA also proposes to concur 

with the evaluation in the 2008 PM2.5 Plan that, at this time, 

ammonia does not need to be considered an attainment plan 

precursor for purposes of attaining the 1997 PM2.5 NAAQS in the 

SJV.

EPA’s proposed concurrence on excluding ammonia and VOC as 

attainment plan precursors in the SJV is limited to the SIP for 

attainment of the 1997 PM2.5 NAAQS. EPA revised the 24-hour PM2.5

standards in 2006 to lower them to 35 μg/m3. Evaluation of 

 

26 In its approval of the SJV 2003 PM10 plan, EPA determined 

that for the purposes of CAA section 189(b)(1)(B) and (e) and in 

the absence of final data from CRPAQS, VOC did not contribute 

significantly to PM10 levels which exceed the standards in the 

SJV. See 69 FR 30006, 30011 (May 26, 2004). We note that EPA 

made that 2004 finding for a different NAAQS (the 24-hour and 

now revoked annual PM10 standards of 150 μg/m3 and 50 μg/m

3, 

respectively), based on criteria for evaluation of precursors 

that differ from those provided in the PM2.5 implementation rule. 

See 72 FR 20586 at 20590-20594 and 40 CFR § 51.1000.
77

whether ammonia and VOC controls may be necessary for the 

expeditious attainment of the 2006 PM2.5 standards and any future 

revised standards may show that such controls would 

significantly contribute to lower PM2.5 levels in the SJV.

4. Extension of the Attainment Date

CAA section 172(a)(2) provides that an area’s attainment 

date “shall be the date by which attainment can be achieved as 

expeditiously as practicable, but no later than 5 years from the 

date such area was designated nonattainment..., except that the 

Administrator may extend the attainment date to the extent the 

Administrator determines appropriate, for a period no greater 

than 10 years from the date of designation as nonattainment 

considering the severity of nonattainment and the availability 

and feasibility of pollution control measures.”

Because the effective date of designations for the 1997 

PM2.5 standards is April 5, 2005 (70 FR 944), the initial 

attainment date for PM2.5 nonattainment areas is as expeditiously 

as practicable but not later than April 5, 2010. For any area 

that is granted a full five-year attainment date extension under 

section 172, the attainment date would be not later than April 

5, 2015.

Section 51.1004 of the PM2.5 implementation rule addresses 

the attainment date requirement. Section 51.1004(b) requires a 

state to submit an attainment demonstration justifying its 
78

proposed attainment date and provides that EPA will approve an 

attainment date when we approve that demonstration.

States that request an extension of the attainment date 

under CAA section 172(a)(2) must provide sufficient information 

to show that attainment by April 5, 2010 is impracticable due to 

the severity of the nonattainment problem in the area and the 

lack of available and feasible control measures to provide for 

faster attainment. 40 CFR § 51.1004(b). States must also 

demonstrate that all RACM and RACT for the area are being 

implemented to bring about attainment of the standard by the 

most expeditious alternative date practicable for the area. 72 

FR 20586 at 20601.

The 2008 PM2.5 Plan includes a demonstration that the 

attainment date for the SJV should be April 5, 2015, i.e., that 

the area qualifies for the full five-year extension of the 

attainment date allowable under section 172(a)(1). This 

demonstration is found in Chapter 9 of the 2008 PM2.5 Plan and is 

updated by information in Appendix C of the 2011 Progress 

Report.

SJV’s PM2.5 nonattainment problem is severe. The area 

typically records the highest ambient PM2.5 levels in the nation, 

with the 2008-2010 design value for the annual PM2.5 levels in 

urban Bakersfield area of 21.2 μg/m3. See EPA, Air Quality 

System, Design Value Report, June 1, 2011. The PM2.5 problem in 
79

the San Joaquin Valley is complex, caused by both direct and 

secondary PM2.5 and compounded by the area’s topographical and 

meteorological conditions that are very conducive to the 

formation and concentration of PM2.5 particles. See 2008 PM2.5

plan, Chapter 3.

As discussed in section V.B.2.a. above, the District's 

strategy for attaining the PM2.5 standard relies on reductions of 

direct PM2.5 as well as the PM2.5 precursor pollutants NOx and SOx. 

The SJV needs significant reductions in direct PM2.5 and NOx to 

demonstrate attainment. Further reducing these pollutants is 

challenging because the State and District have already adopted 

stringent control measures for most sources of direct PM2.5 and 

NOx emissions. Moreover, attainment in the SJV depends upon 

emissions reductions that offset the emissions increases 

associated with projected increases in population.

Reductions of direct PM2.5 are achieved primarily from open 

burning, commercial charbroiling, residential wood combustion, 

and in-use truck and bus control measures. These types of 

control measures present special implementation challenges 

(e.g., the large number of individuals subject to regulation and 

the difficulty of applying conventional technological control 

solutions). NOx reductions come largely from District rules for 

fuel combustion sources and from the State’s mobile source 

rules.
80

Because of the necessity of obtaining additional emissions 

reductions from these source categories in the SJV and the need 

to conduct significant public outreach if applicable control 

approaches are to be effective, EPA agrees with the District and 

CARB that the 2008 PM2.5 Plan reflects expeditious implementation 

of the available control programs during the 2008-2014 time 

frame. EPA also agrees that the implementation schedule for the 

District’s revised stationary source controls is expeditious, 

taking into account the time necessary for purchase and 

installation of the required control technologies. 

In addition, the State has adopted standards for many 

categories of on-road and off-road vehicles and engines, 

gasoline and diesel fuels, as well as improvements to 

California’s vehicle inspection and maintenance program, and 

programs requiring the retrofitting and replacement of in-use 

trucks, buses and off-road equipment. The State is implementing 

these rules and programs as expeditiously as practicable, and it 

is not feasible to accelerate the schedule for new emissions 

standards under the State and Federal mobile source control

program.

EPA also expects that the District and CARB will continue 

to investigate opportunities to accelerate progress toward 

attainment as new control opportunities arise, and that these 
81

agencies will promptly adopt and expeditiously implement any new 

measures found to be feasible in the future.

As discussed in section V.B.3. above, we are proposing to 

approve the RACM/RACT demonstration in the SJV 2008 PM2.5 SIP. As 

discussed below in section V.C.6., we are also proposing to 

approve the attainment demonstration in the SIP. Based on these 

proposed approvals as well as the Plan’s demonstration that 

April 5, 2015 is the most expeditious attainment date 

practicable, EPA is proposing to grant an extension of the 

attainment date for the 1997 PM2.5 standards in the SJV to April 

5, 2015 pursuant to CAA section 172(b)(2) and 40 CFR § 

51.1004(b).

5. Attainment Demonstration

Table 7 below summarizes the reductions that are relied on 

in the 2008 PM2.5 Plan to demonstrate attainment by April 5, 

2015.

Table 7

Summary of Reductions Needed for SJV’s PM2.5 Attainment 

Demonstration

(tons per average annual day)

Direct 

PM2.5

NOx SO2

A. 2005 emissions level 86.0 575.4 26.4

B. 2014 attainment target 63.3 291.2 24.6

C. Total reductions needed 

by 2014 (A - B) 22.7 284.2 1.8

D. Adjustments to 

baseline/reductions from 

baseline(pre-2007) measures 

13.7 258.1 1.0

Percent of total reductions 

from baseline 60% 91% 56%
82

measures/adjustments

E. Reductions needed from 

new measures (C - D) 9.0 26.1 0.8

Percent of total reductions 

needed from new measures 40% 9% 44%

Note: The 2005 emissions level, 2014 attainment target, and 

total reductions needed by 2014 remain unchanged from the 

November 30, 2010 proposal. 

As shown in this table, the majority of the emissions 

reductions that the State projects are needed for PM2.5

attainment in the SJV by 2015 come from baseline reductions. 

These baseline reductions include not only the benefit of 

numerous adopted District and State measures which generally 

have been approved by EPA either through the SIP process or the 

CAA section 209 waiver process but also the effect of the recent 

economic recession on projected future inventories. See 2011 

Progress Report, Appendix E and Appendices A and B of the TSD.

The remaining reductions needed for attainment are to be 

achieved through the District’s and CARB’s commitments to reduce 

emissions in the SJV. Since the submittal of the 2008 PM2.5 Plan 

and 2007 State Strategy, the District and CARB have adopted 

measures (summarized in Table 8 below) that can be credited 

toward reducing their aggregate emissions reduction in their

enforceable commitments.

Table 8

Reductions Needed for Attainment Remaining as 

Commitments

based on SIP-Creditable Measures

(tons per average annual day in 2014)
83

Direct 

PM2.5

NOx SOx

A

Total reductions needed 

from baseline and 

control strategy 

measures to attain

22.7 284.2 1.8

B

Reductions from baseline 

measures

13.7 258.1 1.0

C

Total reductions from 

approved/proposed for 

approval measures

6.0 13.2 3.6

Total reductions 

remaining as commitments 

(A-B-C)

3.0 12.9 0.0

Percent of total 

reductions needed 

remaining as commitments

13.2% 4.5% 0.0%

a. Enforceable Commitments

As shown above, measures already adopted by the District 

and CARB (both prior to and as part of the 2008 PM2.5 Plan) 

provide the majority of emissions reductions the State projects 

are needed to demonstrate attainment. The balance of the needed 

reductions is in the form of enforceable commitments by the 

District and CARB.

The CAA allows approval of enforceable commitments that are 

limited in scope where circumstances exist that warrant the use 

of such commitments in place of adopted measures.27 Once EPA 

 

27 Commitments approved by EPA under CAA section 110(k)(3) 

are enforceable by EPA and citizens under CAA sections 113 and 

304, respectively. In the past, EPA has approved enforceable 

commitments and courts have enforced these actions against 
84

determines that circumstances warrant consideration of an 

enforceable commitment, it considers three factors in 

determining whether to approve the CAA requirement that relies 

on the enforceable commitment: (a) does the commitment address a 

limited portion of the CAA-requirement; (b) is the state capable 

of fulfilling its commitment; and (c) is the commitment for a 

reasonable and appropriate period of time.28

 

states that failed to comply with those commitments. See, e.g., 

American Lung Ass'n of N.J. v. Kean, 670 F. Supp. 1285 (D.N.J. 

1987), aff'd, 871 F.2d 319 (3rd Cir. 1989); NRDC, Inc. v. N.Y. 

State Dept. of Env. Cons., 668 F. Supp. 848 (S.D.N.Y. 1987); 

Citizens for a Better Env't v. Deukmejian, 731 F. Supp. 1448, 

recon. granted in par, 746 F. Supp. 976 (N.D. Cal. 1990); 

Coalition for Clean Air v. South Coast Air Quality Mgt. Dist., 

No. CV 97-6916-HLH, (C.D. Cal. Aug. 27, 1999). Further, if a 

state fails to meet its commitments, EPA could make a finding of 

failure to implement the SIP under CAA section 179(a), which 

starts an 18-month period for the State to correct the nonimplementation before mandatory sanctions are imposed.

CAA section 110(a)(2)(A) provides that each SIP “shall 

include enforceable emission limitations and other control 

measures, means or techniques * * * as well as schedules and 

timetables for compliance, as may be necessary or appropriate to 

meet the applicable requirement of the Act.” Section 172(c)(6) 

of the Act, which applies to nonattainment SIPs, is virtually 

identical to section 110(a)(2)(A). The language in these 

sections of the CAA is quite broad, allowing a SIP to contain 

any “means or techniques” that EPA determines are “necessary or 

appropriate” to meet CAA requirements, such that the area will 

attain as expeditiously as practicable, but no later than the 

designated date. Furthermore, the express allowance for 

“schedules and timetables” demonstrates that Congress understood 

that all required controls might not have to be in place before 

a SIP could be fully approved.

28 The U.S. Court of Appeals for the Fifth Circuit upheld 

EPA's interpretation of CAA sections 110(a)(2)(A) and 172(c)(6) 

and the Agency's use and application of the three factor test in 
85

With respect to the 2008 PM2.5 Plan and 2007 State Strategy, 

circumstances warrant the consideration of enforceable 

commitments as part of the attainment demonstration for this 

area. As shown in Table 7 above, the majority of emissions 

reductions that are needed to demonstrate attainment and RFP in 

the SJV come from rules and regulations that were adopted prior 

to 2007, i.e., they come from the baseline measures.

As a result of these already-adopted District and State 

measures, most sources in the San Joaquin Valley nonattainment 

area were already subject to stringent rules prior to the 

development of the 2007 State Strategy and the 2008 PM2.5 Plan, 

leaving fewer and more technologically challenging opportunities 

to reduce emissions. In the 2008 PM2.5 Plan and the 2009 

revisions to the 2007 State Strategy, the District and CARB 

identified potential control measures that could achieve the 

additional emissions reductions needed for attainment. However, 

the timeline needed to develop, adopt, and implement these 

measures went well beyond the April 5, 200829 CAA deadline to 

submit the PM2.5 plan. As discussed above and below, since 2007, 

 

approving enforceable commitments in the 1-hour ozone SIP for 

Houston-Galveston. BCCA Appeal Group et al. v. EPA et al., 355 

F.3d 817 (5th Cir. 2003).

29 The 2007 State Strategy was developed to address both 

the 1997 PM2.5 NAAQS and the 1997 8-hour Ozone NAAQS. The 8-hour 

ozone SIPs were due in November 2007, and the development and 

adoption of the State Strategy was timed to coordinate with this 

submittal date. 2007 State Strategy, p. 1.
86

the District and State have made progress in adopting measures 

to meet their commitments, but have not completely fulfilled 

them. Given these circumstances, the 2008 PM2.5 Plan’s and 2007 

State Strategy’s reliance on enforceable commitments is 

warranted. We now consider the three factors EPA uses to 

determine whether the use of enforceable commitments in lieu of 

adopted measures to meet CAA planning requirements is 

approvable.

i. The Commitment Represents a Limited Portion of Required 

Reductions

For the first factor, we look to see if the commitment 

addresses a limited portion of a statutory requirement, such as 

the amount of emissions reductions needed for attainment in a 

nonattainment area.

As shown in Table 8, the remaining portion of the 

enforceable commitments in the 2008 PM2.5 Plan and the 2007 State 

Strategy are 3.0 tpd direct PM2.5 and 12.6 tpd NOx after 

accounting for measures that are either approved or proposed for 

approval and revisions to the future year baseline inventories 

resulting from changes to the Plan’s economic forecasts and 

other factors. When compared to the total reductions needed by 

2014 for PM2.5 attainment in the SJV on a per-pollutant basis, 

these remaining commitments represent approximately 13.2 percent 
87

of the direct PM2.5 and 4.5 percent of the NOx needed to attain 

the 1997 PM2.5 standards in the SJV.

We find that the reductions remaining as enforceable 

commitments in the 2008 PM2.5 Plan and 2007 State Strategy 

represent a limited portion of the total emissions reductions 

needed to meet the statutory requirement for attainment in the 

SJV and therefore satisfy the first factor. The level of 

reductions remaining as commitments is reasonably close to the 

10 percent range that EPA has historically accepted in approving 

attainment demonstrations.

30

ii. The State is Capable of Fulfilling its Commitment

For the second factor, we consider whether the State and 

District are capable of fulfilling their commitments. As 

discussed above, CARB has adopted and submitted a 2009 State 

Strategy Status Report and a 2011 Progress Report, which update 

and revise the 2007 State Strategy. These reports show that CARB 

has made significant progress in meeting its enforceable 

commitments for the San Joaquin Valley and several other 

nonattainment areas in California. Additional ongoing programs

that address locomotives and in-use agricultural equipment have 

yet to be quantified but are expected to reduce NOx and direct 

 

30 See, for example, our approval of the SJV PM10 Plan at 69

FR 30005 (May 26, 2004), the SJV 1-hour ozone plan at 75 FR

10420 (March 8, 2010), and the Houston-Galveston 1-hour ozone 

plan at 66 FR 57160 (November 14, 2001).
88

PM2.5 emissions in the SJV by 2014. See 2011 Progress Report, 

Appendix E, page 2.

The District has already exceeded its commitments to reduce

NOx emissions in 2014 by 9 tpd and SOx emissions by 0.9 tpd and 

has substantially met its commitment to reduce direct PM2.5

emissions by 6.7 tpd. See Tables 3 and 4. In addition, it is 

expecting to adopt revisions to District Rule 4702 

(Reciprocating Internal Combustion Engines) later this year that 

are likely to achieve substantial NOx reductions by 2014. See 

SJVUAPCD, Draft Staff Report For Draft Amendments To Rule 4702 

(Internal Combustion Engines–Phase 2), September 9, 2010. It is 

also continuing to work to identify and adopt additional 

measures to reduce emissions. Table F-5 in the TSD describes a 

number of the feasibility studies currently underway at the 

District.

Beyond the rules discussed above, both CARB and the 

District have well-funded incentive grant programs to reduce 

emissions from the on- and off-road engine fleets. See, for 

examples, SJV PM2.5 Progress Report, section 2.3. Reductions from 

several of these programs have yet to be quantified and/or 

credited in the attainment demonstration but efforts are 

underway to do so. See, for example, “Statement of Principles 

Regarding the Approach to State Implementation Plan 

Creditability of Agricultural Equipment Replaced Incentive 
89

Programs Implemented by the USDA Natural Resources Conservation 

Service and San Joaquin Valley Air Pollution Control District,” 

December 2010.

Finally, the SJV is designated nonattainment for the 2006 

24-hour PM2.5 standard. The State must submit a plan to address 

attainment of that standard by December 2012. 74 FR 58688, 58689 

(November 13, 2009).

Given the evidence of the State's and District’s efforts to 

date and their continuing efforts to reduce emissions, we find 

that the State and District are capable of meeting their 

enforceable commitments to reduce emissions of direct PM2.5 and 

NOx by 2014 to the levels needed to attain the 1997 PM2.5

standards in the San Joaquin Valley by its proposed attainment 

date of April 5, 2015.

iii. The Commitment is for a Reasonable and Appropriate 

Timeframe

For the third and last factor, we consider whether the 

commitment is for a reasonable and appropriate period of time.

In order to meet the commitments to reduce emissions to the 

levels needed to attain the 1997 PM2.5 standards in the San 

Joaquin Valley, the 2008 PM2.5 Plan and 2007 State Strategy 

included an ambitious rule development, adoption, and 

implementation schedules, which both the District and CARB have 

substantially met. EPA considers these schedules to provide 
90

sufficient time to achieve by 2014 the few remaining reductions 

needed to attain by the proposed attainment date of April 5, 

2015. We, therefore, conclude that the third factor is 

satisfied.

6. Proposed Action on the Attainment Demonstration

In order to approve a SIP’s attainment demonstration, EPA 

must make several findings and approve the plan’s proposed 

attainment date.

First, we must find that the demonstration’s technical 

bases, including the emissions inventories and air quality 

modeling, are adequate. As discussed above in sections V.A. and 

V.C.2, we are proposing to approve both the emissions 

inventories and the air quality modeling on which the SJV 2008 

PM2.5 Plan’s attainment demonstration and other provisions are 

based.

Second, we must find that the SIP submittal provides for 

expeditious attainment through the implementation of all RACM 

and RACT. As discussed above in section V.B., we are proposing 

to approve the RACM/RACT demonstration in the SJV PM2.5 SIP.

Third, EPA must find that the emissions reductions that are 

relied on for attainment are creditable. As discussed in section 

V.C.5., the 2008 PM2.5 Plan relies principally on adopted and 

approved/waived rules to achieve the emissions reductions needed 

to attain the 1997 PM2.5 standards in the SJV by April 5, 2015. 
91

The balance of the reductions is currently in the form of 

enforceable commitments that account for 13.2 percent of the 

direct PM2.5 and 4.5 percent of the NOx emissions reductions 

needed from 2005 levels for attainment. See Table 8.

EPA has previously accepted enforceable commitments in lieu 

of adopted control measures in attainment demonstrations when 

the circumstances warrant it and the commitments meet three 

criteria. As discussed above in section V.C.5., we find that 

circumstances here warrant the consideration of enforceable 

commitments and that the three criteria are met: 1) the 

commitments constitute a limited portion of the required 

emissions reductions, 2) both the State and the District have 

demonstrated their capability to meet their commitments, and 3) 

the commitments are for an appropriate timeframe. Based on these 

conclusions, we propose to allow the State to rely on these 

limited enforceable commitments in its attainment demonstration.

Finally, for a PM2.5 nonattainment area that cannot attain 

within five years of its designation as nonattainment, EPA must 

grant an extension of the attainment date in order to approve 

the attainment demonstration for the area. As discussed above in 

section V.C.4., we propose to determine that a five-year 

extension of the attainment date is appropriate given the 

severity of the nonattainment problem in the SJV and 

availability and feasibility of control measures and, therefore,
92

to grant the State’s request to extend the attainment date in 

the SJV to April 5, 2015.

For the foregoing reasons, we are proposing to approve the 

attainment demonstration in the SJV 2008 PM2.5 SIP.

D. Reasonable Further Progress Demonstration

1. Requirements for RFP

CAA section 172(c)(2) requires that plans for nonattainment 

areas shall provide for reasonable further progress (RFP). RFP 

is defined in section 171(1) as “such annual incremental 

reductions in emissions of the relevant air pollutant as are 

required by this part or may reasonably be required by the 

Administrator for the purpose of ensuring attainment of the 

applicable [NAAQS] by the applicable date.”

The PM2.5 implementation rule requires submittal of an RFP 

plan at the same time as the attainment demonstration for any 

area for which a state requests an extension of the attainment 

date beyond 2010. For areas for which the state requests an 

attainment date extension to 2015, such as SJV, the RFP plan 

must demonstrate that in the applicable milestone years of 2009 

and 2012, emissions in the area will be at a level consistent 

with generally linear progress in reducing emissions between the 

base year and the attainment year. 40 CFR § 51.1009(d). States 

may demonstrate this by showing that emissions for each 

milestone year are roughly equivalent to benchmark emissions 
93

levels for direct PM2.5 and each PM2.5 attainment plan precursor 

addressed in the plan. The steps for determining the benchmark 

emissions levels to demonstrate generally linear progress are 

provided in 40 CFR § 51.1009(f).

The RFP plan must describe the control measures that 

provide for meeting the reasonable further progress milestones 

for the area, the timing of implementation of those measures, 

and the expected reductions in emissions of direct PM2.5 and PM2.5

attainment plan precursors. See 40 CFR § 51.1009(c).

2. The RFP Demonstration in the SJV 2008 PM2.5 Plan

CARB provided an updated and revised RFP demonstration for 

the SJV in Appendix C of the 2011 Progress Report. The 

demonstration addresses direct PM2.5, NOx, and SO2 and uses the 

2005 annual average day inventory as the base year inventory and 

2014 as the attainment year. The control strategy measures that 

are relied on to demonstrate RFP and the emissions reductions 

from each measure in each year are given in the 2011 Progress 

Report, Appendix C, Table C-1 and supplemental information 

provided by the District.

31 The revised RFP demonstration is 

shown in Table 9 below.

Table 9

RFP Demonstration Using Updated Control Measures and 

Baseline Data

 

31 See SJVUAPCD, “Table 3-1 Adjusted PM2.5 Emission 

Inventory; Table 3-2 Adjusted NOx Emission Inventory; and Table 

3-3 Adjusted SOx Emission Inventory,” March 2011.
94

(tons per annual average day)

Direct 

PM2.5

NOx SO2

2009

Benchmark emissions level 76 449 26

Revised projected 

controlled emissions level 73 387 23

Emissions below benchmark 

emissions level -3 -62 -3

Percent below benchmark 

emissions level -4% -14% -12%

2012

Benchmark emissions level 68 354 25

Revised projected 

controlled emissions level 71 336 20

Emissions above/below 

benchmark emissions level +3 -18 -5

Percent above/below 

benchmark emissions level +4% -5% -20%

Source: Table H-4 in the TSD.

3. Proposed Action on the RFP Demonstration

EPA has reviewed the revised RFP demonstration in the 2011 

Progress Report and has determined that it was prepared 

consistent with applicable EPA regulations and policies. See 

Section II.H of the TSD. As can be seen from Table 9, controlled 

emissions levels for direct PM2.5, NOx, and SOx were below the 

benchmarks for 2009, demonstrating that the SJV met its RFP 

targets in that year. For 2012, the projected controlled 

emissions levels for direct PM2.5 are only slightly above the 

benchmark (by about 4 percent) and the projected controlled 

levels for NOx and SOx are substantially below the benchmarks. We 

find that, overall, these projected controlled emissions levels 

represent generally linear progress for 2012.
95

Based on our evaluation, which is summarized above and 

discussed in detail in section II.H. of the TSD, and our 

proposed concurrence (discussed above in section V.C.3.) with 

the State’s determination that SOx and NOx are and VOC and 

ammonia are not attainment plan precursors per 40 CFR § 

51.1002(c), we propose to find that the SJV 2008 PM2.5 SIP 

provides for reasonable further progress as required by CAA 

section 172(c)(2) and 40 CFR § 51.1009 and that the SJV has met 

its 2009 RFP benchmarks.32

E. Contingency Measures

1. Requirements for Contingency Measures

Under CAA section 172(c)(9), all PM2.5 attainment plans must 

include contingency measures to be implemented if an area fails 

to meet RFP (RFP contingency measures) and contingency measures 

to be implemented if an area fails to attain the PM2.5 NAAQS by 

the applicable attainment date (attainment contingency 

measures). These contingency measures must be fully adopted 

rules or control measures that are ready to be implemented 

 

32 As discussed above in section V.A., CARB has recently 

updated the inventories for several mobile source categories and 

estimates that these updates would reduce, if incorporated into 

those inventories, the Plan’s 2005 base year NOx inventory by 

approximately 6 percent and the direct PM2.5 inventory by 

approximately 5 percent. CARB Progress Report supplement, 

Attachment 1. EPA evaluated the potential impact of revising the

2005 base year inventories on the RFP demonstration and found 

that the Plan would continue to show the RFP. See Section II.H. 

of the TSD.
96

quickly without significant additional action by the state. 40 

CFR § 51.1012. They must also be measures not relied on in the 

plan to demonstrate RFP or attainment and should provide SIPcreditable emissions reductions equivalent to approximately one

year of the emissions reductions needed for RFP. 72 FR 20586 at 

20642-43. Finally, the SIP should contain trigger mechanisms for 

the contingency measures and specify a schedule for their 

implementation. Id.

Contingency measures can include Federal, State and local 

measures already adopted and implemented or scheduled for 

implementation that provide emissions reductions in excess of 

the reductions needed to provide for RFP or expeditious 

attainment. EPA has approved numerous SIPs under this 

interpretation. See, for example, 62 FR 15844 (April 3, 1997) 

direct final rule approving Indiana ozone SIP revision; 62 FR 

66279 (December 18, 1997), final rule approving Illinois ozone 

SIP revision; 66 FR 30811 (June 8, 2001), direct final rule 

approving Rhode Island ozone SIP revision; 66 FR 586 (January 3, 

2001), final rule approving District of Columbia, Maryland, and 

Virginia ozone SIP revisions; and 66 FR 634 (January 3, 2001), 

final rule approving Connecticut ozone SIP revision. The State 

may use the same measures for both RFP and attainment 

contingency if the measures will provide reductions in the 

relevant years; however, should measures be triggered for 
97

failure to make RFP, the State would need to submit replacement 

contingency measures for attainment purposes.

2. Contingency Measures in the SJV 2008 PM2.5 Plan

There are several types of contingency measures in the 2008 

PM2.5 SIP: a new commitment to an action by the District, surplus 

reductions in the RFP demonstration, post-2014 emissions 

reductions, a contingency provision in an adopted rule, and 

reductions from incentive funds and control strategy measures 

that are not relied on in the attainment and RFP demonstrations. 

We discuss each of these types of contingency measures below.

The Plan does not calculate the emissions reductions that 

are equivalent to one year’s worth of RFP. Based on information 

in the Plan, we have calculated one year’s worth of RFP to be 

2.5 tpd direct PM2.5, 31.6 tpd NOx, and 0.2 tpd SO2.. See section 

II.I. of the TSD.

Request CARB to Accelerate State Measure Implementation –

This proposed contingency measure (which could function as both 

a RFP and attainment contingency measure), requires the 

District’s Governing Board to adopt a resolution requesting CARB 

to accelerate the adoption and/or implementation of any 

remaining CARB control measures that have not yet been adopted 

or fully implemented. 2008 PM2.5 Plan, p. 9-7.
98

Under CAA section 172(c)(9) and EPA’s policies33

interpreting this section, contingency measures must require 

minimal additional rulemaking by the state and take effect 

within a few months of a failure to make RFP or to attain. This 

proposed contingency measure would require additional rulemaking 

at the District level and potentially substantial and lengthy 

additional rulemaking at the State level to be implemented. For 

these reasons, this proposed measure does not meet CAA 

requirements for contingency measures.

Surplus Reductions in the RFP Demonstration - In the June 

2008 version of the Plan, the method used to calculate emissions 

reductions needed to meet RFP benchmarks withheld a certain 

percentage of those reductions for contingency purposes: 1 

percent of the baseline PM2.5 inventory and 3 percent of the 

baseline NOx inventory. These percentages equate to roughly 1 tpd 

PM2.5 and 17 tpd NOx being reserved for contingency. No reserve 

was included for SOx because SOx emissions levels were projected 

to be below the applicable benchmarks and these excess 

reductions served as contingency measures. See 2008 PM2.5 Plan, 

p. 8-4.

The 2011 Progress Report updates the RFP demonstrations in 

the 2008 PM2.5 Plan. See 2011 Progress Report, Table C-1. The 

 

33 See “State Implementation Plans; General Preamble for 

the Implementation of Title I of the Clean Air Act Amendments of 

1990,” 57 FR 13498 at 13512 (April 16, 1992).
99

updated demonstration does not include a contingency measure 

reserve but rather shows that expected controlled emissions 

levels of NOx and SOx will be below the required RFP benchmarks. 

SOx reductions that are in excess of those needed to meet RFP and 

contingency are reserved for PM2.5 contingency measures at a 

interpollutant trading ratio of 1 tpd SOx to 1 tpd direct PM2.5. 

See 2011 Progress Report, Appendix A, p. 2 and (for the trading 

ratio), SJV PM2.5 Progress Report, Table 2-2. These excess 

reductions are from SIP-approved or otherwise SIP-creditable 

adopted measures and therefore may be used to meet the 

contingency measure requirement. We do not, however, agree at 

this time with the use of a SOx to direct PM2.5 interpollutant 

trading ratio of 1:1 as the State has not provided an adequate 

technical justification for such a ratio. See Section V.D.2 

above and section II.B.4.

Post-Attainment Year Emissions Reductions – The 2008 PM2.5

Plan relies on the incremental emissions reductions that will 

occur from existing controls in 2015 to provide for contingency 

measures for failure to attain. See p. 9-9. CARB estimates these 

incremental emissions reductions, including reductions expected 

from its In-use Truck and Bus and In-Use Off-Road Engine Rules, 

are 3 tpd SO2 and 21 tpd NOx. CARB Progress Report supplement, 

Attachment 2. These excess reductions are from SIP-approved or 
100

otherwise SIP-creditable adopted measures and therefore may be 

used to meet the contingency measure requirement.

Contingency Provision in Rule 4901 “Wood Burning Fireplace 

and Wood Burning Heaters” – In October, 2008, the District

revised Rule 4901 to incorporate a contingency provision in 

section 5.6.5. This provision requires that 60 days after EPA 

finds the SJV nonattainment area has failed to attain the 1997 

PM2.5 NAAQS, the District will lower the level at which mandatory 

curtailment of residential wood burning is required from a 

predicted level of 30 μg/m3 to 20 μg/m3. EPA approved this rule, 

including the contingency provision, on November 10, 2009. 74 FR 

57907.

This attainment contingency provision in Rule 4901 meets 

the statutory and regulatory requirements for attainment

contingency measures: it is triggered by a failure to attain, 

requires no additional rulemaking by the District, will be fully 

implemented within 60 days of being triggered, and is SIP 

approved. The District has preliminarily quantified the 

emissions reductions expected from this contingency provision at 

1.6 tons of PM2.5 per winter average day.34

Control Strategy Reductions Not Included in the RFP and/or 

Attainment Demonstrations

 

34 Personal communications, Jessica Ferrio, SJVUAPCD, to 

Frances Wicher, EPA, August 27, 2010.
101

In its resolution approving the SJV PM2.5 Plan, CARB 

required the District to adopt two additional contingency 

measures. See CARB Resolution No. 08-28, Attachment A. These 

measures are revisions to SJVUAPCD’s Rule 4307 (Boilers, 2 to 5 

MMBtu) and Rule 4702 (Internal Combustion Engines). While the 

District had already included these rule revisions as Measures 

S-COM-2 and S-COM-6 in the Plan’s control strategy, it had not 

estimated or included the NOx emissions reductions from the 

measures in either the Plan’s RFP or attainment demonstration.

The District adopted revisions to Rule 4307 in October 

2008. Reductions from these rule revisions are now included in 

the revised RFP and attainment demonstrations in the 2011 

Progress Report and are no longer in excess of those 

demonstrations and, therefore, cannot be used to meet the 

contingency measure requirement.

Revisions to Rule 4702 are not yet adopted. As discussed 

above, contingency measure must be fully-adopted measures. 

Therefore, expected emissions reductions from revisions to Rule 

4702 cannot currently be used to meet the contingency measure 

requirement.

Emissions Reductions from Incentive Funds – As noted 

previously, the District has several incentive grant programs 

that have the potential to generate considerable emissions 

reductions. The 2008 PM2.5 Plan suggests the use of these 
102

reductions as contingency measures for failure either to meet 

RFP or to attain. While neither the CAA nor EPA policy bar the 

use of emissions reductions from incentive programs to meet all 

or part of an area’s contingency measure obligation, the 

incentive programs must assure that the reductions are surplus, 

quantifiable, enforceable, and permanent in accordance with EPA 

guidance. See “Improving Air Quality with Economic Incentive 

Programs,” EPA-452/R-01-001 (January 2001).

The 2008 PM2.5 Plan does not identify the incentive grant 

programs expected to generate the emissions reductions, nor the 

quantity of the emissions reductions, that the District intends 

to use to meet the contingency measure requirement. Therefore, 

we are unable to determine if they are SIP creditable, surplus 

to attainment and/or RFP needs, or sufficient to provide the 

one-year’s worth of RFP needed. For these reasons, this proposed 

measure does not currently meet the CAA requirements for 

contingency measures.

3. Proposed Action on the Contingency Measures

We are not evaluating the provisions in the 2008 PM2.5 SIP 

that address contingency measures for failure to meet the 2009 

RFP benchmarks. Information in the 2011 Progress Report shows 

that SJV has met its 2009 benchmarks for direct PM2.5, NOx, and 

SOx. See 2011 Progress Report, Table C-1. Therefore, contingency 

measures for failure to meet the 2009 RFP benchmark no longer 
103

have any meaning or effect under the CAA and do not require any 

further review or action by EPA. In addition, as noted above, 

the purpose of RFP contingency measures is to provide a 

continued progress while the SIP is being revised to meet a 

missed RFP milestone. Failure to meet the 2009 benchmark would 

have required California to revise the SJV PM2.5 Plan to assure 

that the next milestone was met and that the Plan still provided 

for attainment. California has already prepared and submitted a 

revision to the SJV PM2.5 SIP that shows that the SIP continues 

to provide for RFP in 2012 and for attainment by April 5, 2015. 

This revision is the 2011 Progress Report, which is one of the 

submittals that EPA is proposing action on in this notice.

The 2008 PM2.5 Plan includes suggestions for several 

potentially approvable contingency measures as well as several 

measures that do not currently meet the CAA’s minimum 

requirements. The Plan does not, however, provide sufficient 

information for us to determine if the emissions reductions from 

some of the potentially approvable measures are SIP creditable 

(e.g., those from incentive grant programs) and does not 

quantify the expected emissions reductions.

The 2011 Progress Report does show that there are surplus 

reductions in the RFP demonstration for 2012. Appendix C, Table 

C-1. As shown on Table 10, these reductions, however, do not 
104

provide emissions reductions equivalent to one year’s worth of 

RFP when considered on a per-pollutant basis.

35

The continuing implementation of the State’s mobile source 

program in combination with the District’s contingency measure 

in Rule 4901, if triggered, will reduce emissions substantially 

in 2015 (the year after the attainment year of 2014). However, 

as shown on Table 10, these reductions do not provide emissions 

reductions equivalent to one year’s worth of RFP when considered 

on a per-pollutant basis.

Based on this evaluation, EPA proposes to disapprove the 

RFP and attainment contingency measures in the SJV 2008 PM2.5 SIP 

pursuant to CAA section 172(c)(9) and 40 CFR § 51.1012.

Table 10

Summary of Reductions from Contingency Measures

in the SJV 2008 PM2.5 Plan

(tons per average annual day)

Direct 

PM2.5

NOx SOx

Excess reductions in the RFP 0 18 5

 

35 In the 2011 Progress Report, the State asserts that 

these reductions are equal to at least one-year’s worth of RFP 

when considered on a PM2.5 equivalency basis; that is, an air 

quality basis. To make this showing, the State relies in part on 

an interpollutant trading ratio of 1 ton of SOx reductions to 1 

ton of PM2.5 reductions. As discussed in section V.D.2. of this 

notice and V.B.4. of the TSD, EPA has found that the technical 

demonstration submitted in support of this ratio is not adequate 

and is not allowing its use as part of the 2008 PM2.5 Plan. EPA 

may consider additional technical information submitted by the 

State to support an appropriate trading ratio and will provide 

an opportunity for public comment on such new information.
105

demonstration that are 

available to meet the 2012 RFP 

contingency requirements 

(excess reduction in the 2012 

RFP demonstration)

Reductions from contingency 

provision in Rule 9401 and new 

2015 reductions available to 

meet the attainment contingency 

requirement 

1.6 21 3

Reductions equivalent to 1-

year’s worth of RFP 2.5 31.6 0.2

F. Motor Vehicle Emissions Budgets for Transportation Conformity

1. Requirements for Motor Vehicle Emissions Budgets

CAA section 176(c) requires Federal actions in 

nonattainment and maintenance areas to conform to the goals of 

SIPs. This means that such actions will not: (1) cause or 

contribute to violations of a NAAQS, (2) worsen the severity of 

an existing violation, or (3) delay timely attainment of any 

NAAQS or any interim milestone.

Actions involving Federal Highway Administration (FHWA) or 

Federal Transit Administration (FTA) funding or approval are 

subject to the EPA’s transportation conformity rule, codified at 

40 CFR part 93, subpart A. Under this rule, Metropolitan 

Planning Organizations (MPOs) in nonattainment and maintenance 

areas coordinate with State and local air quality and 

transportation agencies, EPA, FHWA, and FTA to demonstrate that 

an area’s regional transportation plans (RTPs) and 

transportation improvement programs (TIPs) conform to the 
106

applicable SIPs. This is typically determined by showing that 

estimated emissions from existing and planned highway and 

transit systems are less than or equal to the motor vehicle 

emissions budgets (MVEB or budgets) contained in the SIP. An 

attainment or RFP SIP should include MVEB for the attainment 

year and each required RFP year, as applicable.

An MPO must use budgets in a submitted but not yet approved 

SIP, after EPA has determined that the budgets are adequate. 

Budgets in submitted SIPs may not be used before they are found 

adequate or are approved. In order for us to find a budget 

adequate, the submittal must meet the conformity adequacy 

requirements of 40 CFR § 93.118(e)(4) and (5). Additionally, 

motor vehicle emissions budgets cannot be approved until EPA 

completes a detailed review of the entire SIP and determines 

that the SIP and the budgets will achieve their intended purpose 

(i.e., RFP, attainment or maintenance). The budget must also 

reflect all of the motor vehicle control measures contained in 

the attainment and RFP demonstrations. See 40 CFR § 

93.118(e)(4)(v).

PM2.5 attainment and RFP plans should identify budgets for 

direct PM2.5 and PM2.5 attainment plan precursors. Direct PM2.5 SIP 

MVEB should include PM2.5 motor vehicle emissions from tailpipes, 

brake wear, and tire wear. States must also consider whether reentrained paved and unpaved road dust or highway and transit 
107

construction dust are significant contributors and should be 

included in the direct PM2.5 budget. See 40 CFR § 93.102(b) and § 

93.122(f) and the conformity rule preamble at 69 FR 40004, 

40031–40036 (July 1, 2004). The applicability of emission 

trading between conformity budgets for conformity purposes is

described in 40 CFR 93.124(c).

2. Motor Vehicle Emissions Budgets in the SJV 2008 PM2.5 Plan

The 2008 PM2.5 Plan included MVEB for direct PM2.5 and NOx for 

the attainment year of 2014 and the RFP years of 2009 and 2012. 

See 2008 PM2.5 Plan, Section 7.2.2 and Appendix C. The direct 

PM2.5 budgets include tailpipe, brake wear, and tire wear 

emissions but do not include paved road, unpaved road, and road 

and transit construction dust because these are not considered 

to be significant contributors to PM2.5 levels in the Valley. No 

budgets for SO2 are included because on-road emissions of SO2 are 

also considered insignificant. No budgets for ammonia or VOC are 

included because these pollutants are not considered attainment 

plan precursors for the 1997 PM2.5 standards in the San Joaquin 

Valley. Id.

In April 2010, based on our initial preliminary review of 

the Plan, EPA found the RFP budgets in the 2008 PM2.5 Plan as 

submitted in 2008 adequate and the attainment budgets inadequate 
108

for transportation conformity purposes.36 We published a notice 

of our findings at 75 FR 26749 (May 12, 2010).

3. Updated Motor Vehicle Emissions Budgets in the 2011 Progress 

Report and Additional Revisions

CARB submitted updated MVEB for the San Joaquin Valley in 

the 2011 Progress Report, Appendices A and D. The updated MVEB

were for direct PM2.5 and NOx for the RFP year of 2012 and the 

attainment year of 2014. No updated budgets were included for 

the RFP year of 2009 because there are no applicable conformity 

analysis years prior to 2012.

The submittal also includes a proposed trading mechanism 

for transportation conformity analyses that would allow future 

decreases in NOx emissions from on-road mobile sources to offset 

any on-road increases in PM2.5, using a NOx:PM2.5 ratio of 9:1. 

Transportation conformity trading mechanisms are allowed under 

40 CFR § 93.124. The basis for the trading mechanism is the SIP 

attainment modeling which establishes the relative contribution 

of each PM2.5 precursor pollutant.

As proposed in the 2011 Progress Report, this trading 

mechanism would only be used, if needed, for conformity analyses 

for years after 2014. To ensure that the trading mechanism does 

 

36 See letter, Deborah Jordan, Air Division Director, EPA 

Region 9, to James M. Goldstene, Executive Officer, CARB, “RE: 

Adequacy Status of San Joaquin Valley PM2.5 Reasonable Further 

Progress and Attainment Plan Motor Vehicle Emissions Budgets,” 

dated April 23, 2010.
109

not impact the ability of the SJV to meet the NOx budget, the NOx

emission reductions available to supplement the PM2.5 budget 

would only be those remaining after the 2014 NOx budget has been 

met. Clear documentation of the calculations used in the trade 

would be included in the conformity analysis. See 2011 Progress 

Report, Appendix D, footnote to Table D-2.

On June 20, 2011, CARB posted on its website technical 

revisions to the updated MVEBs in the 2011 Progress Report that 

were referenced in a June 3rd letter to EPA37. See CARB, “Proposed 

8-Hour Ozone State Implementation Plan Revisions and Technical 

Revisions to the PM2.5 State Implementation Plan Transportation 

Conformity Budgets for the South Coast and San Joaquin Valley 

Air Basins,” Appendix C, June 20, 2011, posted at 

www.arb.ca.gov/planning/sip/2007sip/2007sip.htm. These revised 

updated MVEBs are shown in table 11 below. The technical 

revisions correct data entry errors in the budget calculations 

and remove the emission reductions attributed to SJVAPCD’s Rule 

9510, “Indirect Source Review” (ISR). EPA recently approved Rule 

9510 into the California SIP but disallowed the use of emissions 

reductions from the rule for any SIP purpose including 

transportation conformity. See 75 FR 28509 (May 21, 2010) and 76 

FR 26609 (May 9, 2011).

 

37 See letter, James M. Goldstene, Executive Officer, CARB,

to Deborah Jordan, Air Division Director, EPA Region 9, June 3, 

2011.
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Table 11

Revised Updated PM2.5 MVEB for the San Joaquin Valley 

(tons per average annual day)

County

2012 2014

PM2.5 NOx PM2.5 NOx

Fresno 1.5 35.7 1.1 31.4

Kern (SJV) 1.9 48.9 1.2 43.8

Kings 0.4 10.5 0.3 9.3

Madera 0.4 9.2 0.3 8.1

Merced 0.8 19.7 0.6 17.4

San Joaquin 1.1 24.5 0.9 21.6

Stanislaus 0.7 16.7 0.6 14.6

Tulare 0.7 15.7 0.5 13.8

4. Proposed Action on the Motor Vehicle Emissions Budgets

EPA has evaluated the revised updated budgets against our 

adequacy criteria in 40 CFR § 93.318(e)(4) as part of our review 

of the budgets’ approvability. The results of this review are 

documented in Section II.J. of the TSD. We are also posting a 

notice of availability on our transportation adequacy website at 

http://www.epa.gov/otaq/stateresources/ transconf/currsips.htm. 

EPA is not required under its Transportation Conformity rules to 

find budgets adequate prior to proposing approval of them. We 

will ultimately complete the adequacy review of these budgets. 

That could occur when we take a final action on this SIP or it 

could happen at an earlier date.
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As discussed in sections V.C. and V.D., we have completed 

our detailed review of the 2008 SJV PM2.5 SIP and supplemental 

submittals including the 2011 Progress Report. Based on this 

thorough review of these submittals, we are proposing to approve

the attainment and RFP demonstrations in the 2008 SJV PM2.5 SIP. 

As discussed above, CARB has recently posted revisions to the 

updated budgets that were submitted in the 2011 Progress Report 

and intends to present these budgets for adoption as a SIP 

revision at its July 21, 2011 Board meeting. After reviewing 

these revised updated MVEBs, we are proposing to find them to be 

consistent with the approvable attainment and RFP demonstrations 

and to find that they meet all other applicable statutory and 

regulatory requirements including the adequacy criteria in 

§93.118(e)(4) and (5). Therefore, EPA proposes to approve the 

revised updated MVEB based on the assumption that we will 

receive the revised budgets as a complete SIP revision from the 

State prior to our final action on the SJV PM2.5 SIP. If CARB is 

unable to adopt and submit the revised updated budgets, then EPA 

intends to find inadequate and disapprove the updated MVEB 

contained in the 2011 Progress Report.38 If we disapprove the 

MVEB, a conformity freeze would take effect upon the effective 

 

38 EPA cannot approve or find adequate the updated budgets 

included in the 2011 Progress Report because they include 

uncreditable reductions from the District’s ISR rule and because 

of the technical error in the budget calculations.
112

date of the disapproval(usually 30 days after publication of the 

final action in the Federal Register). A conformity freeze means 

that only projects in the first four years of the most recent 

conforming RTP and TIP can proceed. During a freeze, no new 

RTPs, TIPs or RTP/TIP amendments can be found to conform. See 40 

CFR § 93.120.

5. Proposed Action on the Trading Mechanism

As noted above, CARB included a trading mechanism to be 

used in transportation conformity analyses that use the proposed 

budgets as allowed for under 40 CFR § 93.124. This trading 

mechanism would allow future decreases in NOx emissions from onroad mobile sources to offset any on-road increases in PM2.5, 

using a NOx:PM2.5 ratio of 9:1. As proposed by CARB, the trading 

mechanism would only be used, if needed, for conformity analyses 

for years after 2014. To ensure that the trading mechanism does 

not affect the ability of the SJV to meet the NOx budget, the NOx

emissions reductions available to supplement the PM2.5 budget 

would only be those remaining after the 2014 NOx budget has been 

met. The trading mechanism will be implemented with the 

following criteria. The trading applies only to:

Analysis years after the 2014 attainment year.

On-road mobile emission sources.
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Trades using vehicle NOX emission reductions in excess 

of those needed to meet the NOX budget.

Trades in one direction from NOX to direct PM2.5.

A trading ratio of 9 tpd NOX to 1 tpd PM2.5.

Clear documentation of the calculations used in the trade 

would be included in the conformity analysis. See 2011 Progress 

Report, Appendix D, footnote to Table D-2.

EPA has reviewed the 9:1 NOx:PM2.5 ratio and finds it is an 

appropriate ratio for trading between NOx and direct PM2.5 for 

transportation conformity purposes in the San Joaquin Valley for 

the 1997 PM2.5 NAAQS. The method discussed in the documentation 

appears to be adequate for purposes of assessing the effect of 

area-wide emissions changes, such as are used in conformity 

budgets. See section V.D.2. above and II.B.4. of the TSD.

EPA believes that the 2008 PM2.5 Plan as revised by the 2011 

Progress Report includes an approvable trading mechanism for 

determining transportation conformity after 2014. EPA is 

proposing to approve the trading mechanism and all of the 

criteria included in the footnote to Table D-2 as enforceable 

components of the transportation conformity program for the SJV

for the 1997 PM2.5 NAAQS. EPA is also proposing to approve the 

use of this ratio in transportation conformity determinations 

for the 2006 24-hour PM2.5 NAAQS but only until EPA finds 
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adequate or approves budgets developed specifically for the 2006 

24-hour PM2.5 standard. Until that time, conformity will be 

determined using the budgets for the 1997 annual PM2.5 NAAQS.

VI. EPA’s Proposed Actions and Potential Consequences

A. EPA’s Proposed Approvals and Disapprovals

For the reasons discussed above, EPA proposes to approve, 

with the exception of the contingency measures and one 

commitment by the SJVUAPCD, California’s SIP for attaining the 

1997 PM2.5 NAAQS in the San Joaquin Valley and to grant the 

State’s request for an extension of the attainment date. This 

SIP is composed of the SJVUAPCD’s 2008 PM2.5 Plan as revised in 

2010 and 2011 and the SJV-specific portions of CARB’s 2007 State 

Strategy as revised in 2009 and 2011 addressing CAA and EPA 

regulations for attainment of the 1997 PM2.5 NAAQS in the SJV.

Specifically, EPA proposes to approve under CAA section 

110(k)(3) the following elements of the SJV PM2.5 attainment SIP:

1. the 2005 base year emissions inventories as meeting the 

requirements of CAA section 172(c)(3) and 40 CFR § 51.1008;

2. the reasonably available control measures/reasonably 

available control technology demonstration as meeting the 

requirements of CAA section 172(c)(1) and 40 CFR § 51.1010;

3. the reasonable further progress demonstration as meeting 

the requirements of CAA section 172(c)(2) and 40 CFR § 51.1009;
115

4. the attainment demonstration as meeting the requirements 

of CAA sections 172(c)(1) and (6) and 40 CFR § 51.1007;

5. the air quality modeling as meeting the requirements of 

the CAA and EPA guidance;

6. the revised updated 2012 RFP year and 2014 attainment 

year motor vehicle emissions budgets as posted by CARB on June 

21, 2011 contingent upon our receipt of a SIP revision because 

they are derived from approvable RFP and attainment 

demonstrations and meet the requirements of CAA section 176(c) 

and 40 CFR part 93, subpart A and CARB’s trading mechanism to be 

used in transportation conformity analyses as allowed under 40 

CFR § 93.124;

7. SJVUAPCD's commitments to the adoption and 

implementation schedule for specific control measures listed in 

Table 6-2 (amended June 15, 2010) of the 2008 PM2.5 Plan to the 

extent that these commitments have not yet been fulfilled, and 

to achieve specific aggregate emissions reductions of direct 

PM2.5, NOx and SOx by year, as listed in Table 6-3 of the PM2.5

Plan, except for the commitment to adopt revisions to Rule 4702; 

and 

8. CARB's commitments to propose certain defined measures, 

as listed in Table B-1 on page 1 of Appendix B of the 2011 

Progress Report and to achieve aggregate emissions reductions by 
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2014 sufficient to provide for attainment of the 1997 PM2.5 NAAQS 

as described in CARB Resolution 07-28, Attachment B. 

EPA also proposes to concur with the State’s determination 

under 40 CFR § 51.1002(c) that SOx and NOx are and VOC and 

ammonia are not attainment plan precursors for the attainment of 

the 1997 PM2.5 NAAQS in the SJV.

EPA proposes to grant, pursuant to CAA section 172(a)(2)(A) 

and 40 CFR § 51.1004(a), California's request to extend the 

attainment date for the San Joaquin Valley PM2.5 nonattainment 

area to April 5, 2015.

EPA proposes to disapprove under CAA section 110(k)(3) the 

contingency measures provisions of the SJV PM2.5 attainment SIP 

as failing to meet the requirements of CAA section 172(c)(9) and 

40 CFR § 51.1012.

Finally, EPA proposes to disapprove the commitment by the 

SJVUAPCD to adopt revisions to Rule 4702 “Reciprocating Internal 

Combustion Engines” by December 2010 because that date has 

passed and the District has not adopted revisions to the rule. 

We will not finalize this proposed disapproval, however, if the

District adopts revisions to the rule that fulfill the 

commitment by the time of EPA’s final action on the Plan.

B. CAA Consequences of a Final Disapproval

EPA is committed to working with the District, CARB and the 

SJV MPOs to resolve the remaining issues that make the current 
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PM2.5 attainment SIP for the SJV not fully approvable under the 

CAA and the PM2.5 implementation rule. However, should we 

finalize the proposed disapproval of the contingency measure 

provisions in the SJV 2008 PM2.5 Plan or finalize a disapproval 

of the MVEB, the offset sanction in CAA section 179(b)(2) would 

apply in the SJV PM2.5 nonattainment area 18 months after the 

effective date of a final disapproval. The highway funding 

sanctions in CAA section 179(b)(1) would apply in the area six 

months after the offset sanction is imposed. Neither sanction 

will be imposed under the CAA if California submits and we 

approve prior to the implementation of the sanctions, SIP 

revisions that correct the deficiencies identified in our 

proposed action. In addition to the sanctions, CAA section 

110(c)(1) provides that EPA must promulgate a federal 

implementation plan addressing the deficient elements in the 

PM2.5 SIP for the SJV nonattainment area, two years after the 

effective date of any disapproval should we not approve a SIP 

revision correcting the deficiencies within the two years.

Neither sanctions nor a FIP would be imposed should EPA 

disapprove the District’s discretionary commitment to revise 

Rule 4702. Sanctions would not be imposed because the District’s 

decision to include the commitment in its Plan was discretionary 

(i.e., not required to be included in the SIP), and EPA would 

not promulgate a FIP in this instance because the disapproval 
118

does not reveal a deficiency in the PM2.5 SIP that such a FIP 

must correct. This is because the failure of the District to 

adopt revisions to Rule 4702 would not adversely affect the 2008 

PM2.5 SIP’s compliance with the CAA’s mandated requirements for 

RACM/RACT, RFP, and/or attainment demonstrations nor would it 

prevent EPA from granting an extension of the attainment date 

under CAA section 172(b).

Because we are proposing to approve the RFP and attainment 

demonstrations and the motor vehicle emission budgets, we are 

proposing to issue a protective finding under 40 CFR

§ 93.120(a)(3) to the disapproval of the contingency measures. 

Without a protective finding, final disapproval would result in 

a conformity freeze, under which only projects in the first four 

years of the most recent conforming Regional Transportation Plan 

and Transportation Improvement Programs can proceed. During a 

freeze, no new RTPs, TIPs or RTP/TIP amendments can be found to 

conform. See 40 CFR § 93.120(a)(2). Under a protective finding, 

however, final disapproval of the contingency measures would not 

result in a transportation conformity freeze in the San Joaquin 

PM2.5 nonattainment area.

VI. Statutory and Executive Order Reviews

Under the CAA, the Administrator is required to approve a 

SIP submittal that complies with the provisions of the Act and 

applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR § 
119

52.02(a). Thus, in reviewing SIP submittals, EPA’s role is to 

approve state choices, provided that they meet the criteria of 

the CAA. Accordingly, this action merely proposes to partially 

approve and partially disapprove State law as meeting Federal 

requirements and does not impose additional requirements beyond 

those imposed by State law.

A. Executive Order 12866, Regulatory Planning and Review 

This action is not a "significant regulatory action" under 

the terms of Executive Order (EO) 12866 (58 FR 51735, October 4, 

1993) and is therefore not subject to review under the EO.

B. Paperwork Reduction Act

This action does not impose an information collection 

burden under the provisions of the Paperwork Reduction Act, 44 

U.S.C. 3501 et seq, because this proposed SIP partial approval 

and partial disapproval under CAA section 110 and subchapter I, 

part D will not in-and-of itself create any new information 

collection burdens but simply approves certain State 

requirements for inclusion into the SIP and disapproves others. 

Burden is defined at 5 CFR 1320.3(b).

C. Regulatory Flexibility Act

The Regulatory Flexibility Act (RFA) generally requires an 

agency to conduct a regulatory flexibility analysis of any rule 

subject to notice and comment rulemaking requirements unless the 

agency certifies that the rule will not have a significant 
120

economic impact on a substantial number of small entities. Small 

entities include small businesses, small not-for-profit 

enterprises, and small governmental jurisdictions. For purposes 

of assessing the impacts of today's rule on small entities, 

small entity is defined as: (1) a small business as defined by 

the Small Business Administration’s (SBA) regulations at 13 CFR 

121.201; (2) a small governmental jurisdiction that is a 

government of a city, county, town, school district or special 

district with a population of less than 50,000; and (3) a small 

organization that is any not-for-profit enterprise which is 

independently owned and operated and is not dominant in its 

field.

After considering the economic impacts of today’s proposed

rule on small entities, I certify that this action will not have 

a significant impact on a substantial number of small entities.

This rule does not impose any requirements or create impacts on 

small entities. This proposed partial approval and partial 

disapproval of the SIP under CAA section 110 and subchapter I, 

part D will not in-and-of itself create any new requirements but 

simply approves certain State requirements for inclusion into 

the SIP and disapprove others. Accordingly, it affords no 

opportunity for EPA to fashion for small entities less 

burdensome compliance or reporting requirements or timetables or 

exemptions from all or part of the rule. The fact that the CAA 
121

prescribes that various consequences (e.g., higher offset 

requirements) may or will flow from a final disapproval does not 

mean that EPA either can or must conduct a regulatory 

flexibility analysis for this action. Therefore, this action 

will not have a significant economic impact on a substantial 

number of small entities.

We continue to be interested in the potential impacts of 

this proposed rule on small entities and welcome comments on 

issues related to such impacts.

D. Unfunded Mandates Reform Act

This action contains no Federal mandates under the 

provisions of Title II of the Unfunded Mandates Reform Act of 

1995 (UMRA), 2 U.S.C. 1531-1538 for State, local, or tribal 

governments or the private sector.” EPA has determined that the 

proposed partial approval and partial disapproval action does 

not include a Federal mandate that may result in estimated costs 

of $100 million or more to either State, local, or tribal 

governments in the aggregate, or to the private sector. This 

action proposes to partially approve and partially disapprove 

pre-existing requirements under State or local law, and imposes 

no new requirements. Accordingly, no additional costs to State, 

local, or tribal governments, or to the private sector, result 

from this action.

E. Executive Order 13132, Federalism
122

Executive Order 13132, entitled “Federalism” (64 FR 43255, 

August 10, 1999), requires EPA to develop an accountable process 

to ensure “meaningful and timely input by State and local 

officials in the development of regulatory policies that have 

federalism implications.” “Policies that have federalism 

implications” is defined in the Executive Order to include 

regulations that have “substantial direct effects on the States, 

on the relationship between the national government and the 

States, or on the distribution of power and responsibilities 

among the various levels of government.”

This action does not have federalism implications. It will 

not have substantial direct effects on the States, on the 

relationship between the national government and the States, or 

on the distribution of power and responsibilities among the 

various levels of government, as specified in Executive Order 

13132, because it merely partially approves and partially 

disapproves certain State requirements for inclusion into the 

SIP and does not alter the relationship or the distribution of 

power and responsibilities established in the CAA. Thus, 

Executive Order 13132 does not apply to this action.

F. Executive Order 13175, Coordination with Indian Tribal 

Governments

This action does not have tribal implications, as specified 

in Executive Order 13175 (65 FR 67249, November 9, 2000), 
123

because the SIP EPA is proposing to partially approve and 

partially disapprove would not 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. Thus, 

Executive Order 13175 does not apply to this action. 

G. Executive Order 13045, Protection of Children from 

Environmental Health Risks and Safety Risks

EPA interprets EO 13045 (62 FR 19885, April 23, 1997) as 

applying only to those regulatory actions that concern health or 

safety risks, such that the analysis required under section 5-

501 of the EO has the potential to influence the regulation. 

This action is not subject to EO 13045 because it because it is 

not an economically significant regulatory action based on 

health or safety risks subject to Executive Order 13045 (62 FR 

19885, April 23, 1997). This proposed partial approval and 

partial disapproval of the SIP under CAA section 110 and 

subchapter I, part D will not in-and-of itself create any new 

regulations but simply disapproves certain State requirements 

for inclusion into the SIP.

H. Executive Order 13211, Actions that Significantly Affect 

Energy Supply, Distribution, or Use

This proposed rule is not subject to Executive Order 13211 

(66 FR 28355, May 22, 2001) because it is not a significant 

regulatory action under Executive Order 12866.
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I. National Technology Transfer and Advancement Act

Section 12(d) of the National Technology Transfer and 

Advancement Act of 1995 (NTTAA), Public Law No. 104-113, 12(d) 

(15 U.S.C. 272 note) directs EPA to use voluntary consensus 

standards in its regulatory activities unless to do so would be 

inconsistent with applicable law or otherwise impractical. 

Voluntary consensus standards are technical standards (e.g., 

materials specifications, test methods, sampling procedures, and 

business practices) that are developed or adopted by voluntary 

consensus standards bodies. NTTAA directs EPA to provide 

Congress, through OMB, explanations when the Agency decides not 

to use available and applicable voluntary consensus standards.

The EPA believes that this action is not subject to 

requirements of Section 12(d) of NTTAA because application of 

those requirements would be inconsistent with the CAA.

J. Executive Order 12898: Federal Actions to Address 

Environmental Justice in Minority Populations and Low-Income 

Populations

Executive Order (EO) 12898 (59 FR 7629 (Feb. 16, 1994)) 

establishes federal executive policy on environmental justice. 

Its main provision directs federal agencies, to the greatest 

extent practicable and permitted by law, to make environmental 

justice part of their mission by identifying and addressing, as 

appropriate, disproportionately high and adverse human health or 
125

environmental effects of their programs, policies, and 

activities on minority populations and low-income populations in 

the United States.

EPA lacks the discretionary authority to address 

environmental justice in this proposed action. In reviewing SIP 

submittals, EPA’s role is to approve or disapprove State 

choices, based on the criteria of the CAA. Accordingly, t his 

action merely proposes to approve certain State requirements for 

inclusion into the SIP under CAA section 110 and subchapter I, 

part D and to disapprove others will not in-and-of itself create 

any new requirements. Accordingly, it does not provide EPA with 

the discretionary authority to address, as appropriate, 

disproportionate human health or environmental effects, using 

practicable and legally permissible methods, under Executive 

Order 12898.

List of Subjects in 40 CFR Part 52

Environmental protection, Air pollution control, Nitrogen 

dioxide, Particulate matter, Reporting and recordkeeping 

requirements, Sulfur oxides, Volatile organic compounds.

AUTHORITY: 42 U.S.C. 7401 et seq.

June 29, 2011 /s/

_______________________ ___________________________

Dated: Jared Blumenfeld,

Regional Administrator,

EPA Region 9