Page 1 of 37

_____________________________________________________________________________________



# Final T echnical S upport D ocument

_____________________________________________________________________________________



## Final Rulemaking Action on the South Coast PM 10 

## Redesignation Request and Maintenance Plan

June 2013Page 2 of 37

For q uestions about this document

, please contact Wienke Tax, EPA Region 9, 415

- 947

- 4192 , or LaWeeda Ward, 213

- 244

- 1812.



## Table of Contents

I. Background

A. PM 10 

### NAAQS
B. PM 10 

### NAAQS Designations
C. PM 10 

### Planning Requirements

II. Review of SIP Submittal

A. Maintenance Plan Requirements
1. Attainment Emissions Inventory
2. Maintenance Demonstration
3. Monitoring Network
4. Commitment to Subsequent Maintenance Plan Revision

B. Transportation Conformity

III. Response to Comments



## List of Tables

Table B.1. South Coast Air Basin PM 10 

### Expected Exceedances (EE) and Completeness, 2007

- 201 2 Table C

- 1. Annual Average Day Attainment Baseline Emissions Inventory (tons per day) Table C

- 2. Annual Average Day Attainment Emissions Inventory for PM 10 

### Sources (tons per day) Table D

- 1. PM 10 

### Peak Concentrations Table D

- 2. County Level Estimate of Fine and Coarse PM 10 

### Peak Concentration Table D

- 3. County Level Estimate of Relative Reduction Factors for Fine PM 10 

### Peak Concentrations Table D

- 4. Projected 24

- hour PM 10 

### (μg/m 3 

### ) for 2023 and 2030 Table E

- 1. 2009 South Coast PM 10 

### Redesignation Request and Maintenance Plan Motor Vehicle Emissions Budgets as submitted in the Final South Coast PM 10 

### Redesignation Request and Maintenance Plan Table E

- 2. Transportation Conformity Budgets Detail for PM 10 Table E.3

. Evaluation of the Mot or Vehicle Emissions Budget for the Request for PM 10 

### Redesignation and Maintenance Plan for South Coast Air Basin



## List of Figures

Figure B

- 1 Ambient 

### PM 10 Monitoring Locations in the South Coast Air BasinPage 3 of 37



## I. Background

A. PM 10 

### NAAQS

The Clean Air Act (CAA or Act), which was last amended in 1990, requires the United States Environmental Protection Agency (EPA) to set National Ambient Air Quality Standards (NAAQS or standards ) for wide

- spread pollutants from numerous and diverse sources
considered harmful to public health and the environment. The CAA also requires EPA to periodically review the standards to ensure that they provide adequate health and environmental protection, and to update those standards as necessary. Thus EPA set NAAQS for particulate matt er and five other pollutants considered harmful to public health and the environment (the other pollutants are ozone, nitrogen oxides, carbon monoxide, sulfur dioxide and lead). These six pollutants are known as “criteria pollutants”.

"Particulate matter ," also known as particle pollution or PM, is a complex mixture of extremely small particles and liquid droplets. Particle pollution is made up of a number of components, including acids (such as nitrates and sulfates), organic chemicals, metals, and soil or dust particles. The size of particles is directly linked to their potential for causing health problems. EPA is concerned about particles that are 10 micrometers in diameter or smaller because those are the particles that generally pass through the thro at and nose and enter the lungs. Once inhaled, these particles can affect the heart and lungs and cause serious health
effects. EPA groups particle pollution into two categories:

 "Inhalable coarse particles," such as those found near roadways and dusty ind ustries, and possess aerodynamic diameters larger than 2.5 micrometers and smaller than 10

micrometers (PM 10 

### )

.

 "Fine particles," such as those found in smoke and haze, posses s aerodynamic
diameters 2.5 micrometers in diameter and smaller (PM 2.5 

### ) . These particles can be directly emitted from sources such as forest fires, or they can form when gases emitted from power plants, industries and automobiles react in the air.

Within the South Coast A ir B asin
, PM 10 

### particles are either directly emitted into the atmosphere (e.g., primary particles), or are formed through atmospheric chemical reactions from precursor gases (e.g., secondary particles). Primary PM 10 

### include s road dust, diesel soot, combustion products, and other sources of fine particles. Direct PM 10 

### emissions in the South Coast are dominated by re

- entrained road dust from paved and unpaved roads, constructionPage 4 of 37



### and demolition, and on

- and off

- road mobile sources

. Secondary products, such as sulfates, nitrates, and complex carbon compounds are formed from reactions with oxides of sulfur, oxides of nitrogen, volatile organic compounds ( VOCs ) and ammonia.

While NAAQS are set for PM 2.5 

### , the subject of this rulemaking is PM 10 

### . EPA first set a
NAAQS for total suspended particulates (TSP) in 1971

. At that time, the reference method for collecting particulate samples for comparison to the standard was the "high

- volume" sampler. This type of sampler collected particulate matter up to a size of 45 micrometers (μm) in
diameter. The 24

- hour primary and secondary TSP NAAQS were set at 260 and 150 micrograms per cubic meter (μg/m 3 

### ) , respectively, while the annual TSP NAAQS was set at 75 μg/m 3



### . EPA revised the NAAQS for particulate matter on July 1, 1987 (52 FR 24672), replacing standards for

TSP with new standards applying only to PM 10 

### . At that time, EPA established both an annual

PM 10 

### standard and a 24

- hour standard.

 The annual PM 10 

### standard of 50 micrograms per cubic meter (μg/m 3 

### ) is attained when the expected annual arithmetic mean of the 24

- hour samples averaged over a

3

- year period does not exceed 50 μ g/m 3



### .

 The 24

- hour standard of 150 μ g/m 3 

### is attained if samples taken for 24

- hour periods have no more than one expected exceedance per year, averaged over three years

. 1



### On July 18, 1997, EPA established a new NAAQS for PM 2.5 

### ( 62 FR 38652 ) . In this same
action EPA also revised the standards for PM 10 

### but these revised PM 10 

### standards were later vacated by the court, and the 1987 PM 10 

### standards remained in effect. On October 17, 2006

, EPA retained the 24

- hour PM 10 

### standard s but revoked the annual standard s , effective December 18, 2006

. ( 71 FR 61144 ) On January 13, 2013, EPA announced that it was again retaining the 24

- hour PM 10 

### NAAQS as a 24

- hour standard of 150 micrograms per cubic meter ( μ g/m 3 

### ). 2



### B. PM 10 

### NAAQS Designations

On the date of enactment of the 1990 CAA Amendments, PM 10 

### areas, including the

1 See 40 CFR 50.6 and 40 CFR part 50, appendix K.

2 See 78 FR 3086.Page 5 of 37



### South Coast Air Basin
, 3 

### meeting the qualifications of section 107(d)(4)(B) of the amended Act, and in accordance with CAA section 188(a) were initially designated “moderate” nonattainment by operation of law 4 

### with an applicable attainm ent deadline of December 31, 2001

. Section 188(b)(1) of the Act further provides that moderate areas can subsequently be reclassified as

“ serious ” before the applicable moderate area attainment date if at any time EPA determines that the area cannot “practicably” attain the PM 10 

### NAAQS by this attainment date.

EPA determined on January 8, 1993, that the South Coast could not practicably attain
the PM 10 

### NAAQS by the applicable attainment deadline for moderate areas (December 31, 1994, pursuant to section 188(c)(1) of the Act), and reclassified the area as serious (58 FR 3334).

C. PM 10 

### P lanning Requirements

The 1990 CAA Amendments established new planning requirements that states must
use to demonstrate attainment of the N AAQS. The most fundamental of these nonattainment area provisions applicable to the South Coast Air Basin is the requirement that the State submit

a State Implementation Plan ( “ SIP ” or “Plan” ) demonstrating attainment of the PM 10 

### NAAQS. This demonstration must be based upon enforceable measures to achieve emission reductions leading to emissions at or below the level predicted to result in at tainment of the NAAQS throughout the nonattainment area. The measures must meet the standard for Reasonably Available Control Measures ( R ACM), and the measures must be implemented expeditiously and ensure attainment no later than the applicable CAA deadlin e

. 5



### After the South Coast Air Basin was reclassified as serious non attainment for PM 10 

### , in accordance with section 189(b)(2) of the CAA , the State was required to make the following SIP
submittals :

1. The State had to submit by August 8, 1994, a SIP to ensure the implementation of Best Available Control Measures (BACM) no later than four years after reclassification, as required by CAA section 189(b)(1)(B).

3 The South Coast air basin inclu des Orange County, the southwestern two

- thirds of Los Angeles County, southwestern San Bernardino County, and western Riverside County (see 40 CFR 81.305)

.

4 See 56 FR 11101 (March 15, 1991) and 40 CFR 81.305.

5 See CAA Section 189(b)Page 6 of 37



### 2. T he State had to submit a SIP by February 8, 1997, providing for progress and expeditious atta inment, as required by CAA section 189(b)(1)(A).

3. T he State requested an extension of the attainment date for the South Coast beyond the applicable deadline of December 31, 2001, therefore, under CAA section 188(e) the
State also had to demonstrate that the plan contain ed the most stringent measures (MSM) that are included in any implementation plan or are achieved in practice, and can feasibly be implemented in the area.

D. PM 10 

### Nonattainment Plans for the South Coast Area

Commencing in the 1970s and continuing to the present, the South Coast Air Quality Management District ( SCAQMD ) and the California Air Resources Board ( CARB ) have adopted

numerous rules and SIPs to address planning requirements for the South Coast PM 10 

### nonattainment area under the CAA. In 2003, EPA fully approved a PM 10 

### attainment plan for the South Coast as meeting all CAA requirements for serious PM 10 

### areas, and as part of that action we also granted attainment date extensions for the area for both the 24

- hour and annual PM 10 

### NAAQS, from December 31, 2001 to December 31, 2006, pursuant to CAA section 188(e)

. 6 

### On August 1, 2003, the SCAQMD adopted the 20 03 South Coast Air Quality Management Plan (2003 South Coast AQMP or 2003 South Coast SIP ) including the motor vehicle emissions budgets (budget s ) for the area

. CARB adopted the plans on October 23, 2003, and submitted the plans to EPA on January 9, 2004. EPA proposed to approve the portions of the 2003 South Coast AQMP relating to attainment of the PM 10 

### standards on July 28, 2005 7 

### and finalized our approval on November 14, 2005

. 8



### CARB also submits local rules adopted by SCAQMD as well as its own rules to EPA as
revisions to the SIP. Examples of rules adopted by SCAQMD and approved by EPA as revisions
to the California SIP PM 10 

### control strategy i nclude:

 Rule 403

- Fugitive Dust;

 Rule 1186

– PM 10 

### Emissions from Paved and Unpaved Roads, and Livestock Operations;

6 For more information on the 2003 approval of the South Coast PM 10 plan, please see our proposed and final rulemaking notices. The proposal was issued on December 17, 2002 (67 FR 77212) and the final approval was issued on April 18, 2003 (68 FR 19316).

7 see 70 FR 43663

8 see 70 FR 69081Page 7 of 37



###  Rule 1156

– PM 10 

### Emissions Reductions from Cement Manufacturing Facilities;

 Rule 1157

- PM 10 

### Emissions Reductions from Aggregate and Related Operations.

Examples of rules adopted by CARB and approved by EPA as revisions to the California SIP PM 10 

### control strategy include:

 CCR, Title 13, Section 2025 (“Regulation to Reduce Emissions of Diesel Particulate Matter, Oxides of Nitrogen and other Criteria Pollutants, from In

- Use Heavy

- Duty Diese l

Fueled Vehicles”);

 Section 2027 (“In

- Use On

- Road Diesel

- Fueled Heavy

- Duty Drayage trucks”); and

 Section 2262 (“California Reformulated Gasoline Phase 2 and Phase 3 Standards”).

1. SCAQMD’s Request for Redesignation and Maintenance Plan

SCAQMD has submitted both a maintenance plan and a request for redesignation to

attainment of the PM 10 

### standard. According to CAA Section 175 A(a) , a maintenance SIP should provide for maintenance of the PM 10 

### standard for at least 10 years after the redesignation

. Additionally, as required in CAA Section 175 A (b), 8 years after redesignation, South Coast is required to submit a revision of the SIP that demonstrates maintenance of the standard for 10 years after the expiration of the original 10

- year m aintenance period. We expect to act on this redesignation request in 2013, therefore the submitted SIP and budgets must show
maintenance of the PM 10 

### standard through at least the year 2023 (10

- years after the date of redesignation).

T he SCAQMD adopted the Final PM 10 

### Redesignation Request and Maintenance Plan for the South Coast Air Basin (December 2009) ( 2009 South Coast PM 10 

### Redesignation Request
and Maintenance Plan ) on January 8, 2010 and forwarded it to CARB on January 15, 2010 . CARB held a Board Hearing on March 25 , 2010 to adopt the 2009 South Coast PM 10 

### Redesignation Request and Maintenance Plan . The plan was submitted to EPA on April 28, 2010

. 9 

### CARB's SIP submittal includes the following documents:

 April 2 8

, 2010 letter to J ared Blumenfeld, Regional Administrator, U.S. EPA Region 9, from James N. Goldstene, Executive Officer, CARB transmitting the redesignation request and maintenance plan;

9 See letter, James N. Goldstene, Executive Officer, to Jared Blumenfeld, Regional Administrator, EPA Region 9, dated April 28, 2010.Page 8 of 37



###  January 15

, 2010 transmittal letter to James N. Goldstene, Executive Officer, CARB, f rom Elaine Chang

, DrPH, Deputy Executive Officer, SCAQMD;

 October 17, 2009 Proof of Publication of Public Notice for Public Hearing on “Final

PM 10 

### Redesignation Request and Maintenance Plan for the South Coast Air Basin (December 2009)” and the January 8, 2010 SCAQMD Board Hearing;

 Transcripts of public hearings;

 SCAQMD Board Resolution of Adoption 10

- 1 approving and adopting the 2009
South Coast PM 10 

### Maintenance Plan;

 CARB’s February 17, 2010 Notice of Public Hearing for consideration of the adoption and approval of the 2009 South Coast PM 10 

### Redesignation Request and Maintenance Plan and associated motor vehicle emissions budgets on March 25, 2010;

 Final PM 10 

### Redesignation Request and Maintenance Plan for the South Coast Air Basin (December 2009);

 CARB Board Resolution 10

- 21 adopting the 2009 South Coast PM 10 

### Redesignation Request and Maintenance Plan and t ransportation conformity budgets

.

2. Requirements for Redesignation

CAA Section 107(d)(3)(E) describe s the following crit eria for redesignating an area from

nonattainment to attainment:

 EPA must determine that the area has attained the applicable NAAQS;

 EPA has fully approved the applicable implementation plan for the area under section 110(k) of the CAA;

 EPA must determine that the improvement in air quality is due to permanent and enforceable reductions in emissions resulting from implementation of the applicable SIP, applicable Federal air pollution control regulations, and other permanent and enforceable reductions;

 EPA must fully approve a maintenance plan for the area as meeting the requirements of section 175A of the CAA; and

 T he State has met all applicable requirements for the area un der section 110 and

Part D 10 

### of the CAA.

10 The Clean Air Act, as amended in 1990, contains six subchapters. Subchapter I, “Programs and Activities” is divided in six parts (Parts A through D). Part A, “Air Quality and Emission Limitations” contains section 110, whichPage 9 of 37



### 3. EPA Regulations and Guidance

EPA has issued the “State Implementation Plans; General Preamble for the Implementation of Title I of the Clean Air Act Amendments of 1990,” (“General Preamble”) that
describe s the Agenc y's preliminary views on how EPA intends to act on SIPs submitted under
Title I of the Act

. 11 

### Additional guidance is provided in the following:

 “Procedures for Processing Request to Redesignate Areas to Attainment,” John Calcagni, Director, Air Quality Management Division, EPA Office of Air Quality Planning and Standards

, September 4, 1992 EPA guidance document, ( referred
to as the “ Calcagni mem o”)

 “Part D New Source Review (part D NSR) Requirements for Areas Requesting Redesignation to Attainment,” Mary D. Nichols, Assistant Administrator for Air and Radiation, October 14, 1994 (Nichols Memo);

 “State Implementation Plans for Serious PM 10 

### Nonatta inment Areas, and
Attainment Date Waivers for PM 10 

### Nonattainment Areas Generally; Addendum to the General Preamble for the Implementation of title I of the Clean Air Act Amendments of 1990,” 59 FR 41998 (August 16, 1994) ( PM 10 

### Addendum).

provide for basic SIP requirements. Section 110 identifies a comprehensive list of elements that SIPs must include, and par t D establishes the SIP requirements for nonattainment areas. Additional SIP requirements for non

attainment areas are contained in Part D, “Plan Requirements for Nonattainment Areas”. Part D is further divided into six subparts. Generally applicable non attainment SIP requirements are found in part D, subpart 1, and the particulate

- specific nonattainment SIP requirements are found in part D, subpart 4

.

11 See 57 FR 13498 (April 16, 1992), 57 FR 18070 (April 28, 1992)Page 10 of 37



## II. Review of the So uth Coast Submittal

A. Selected Redesignation Request and Maintenance Plan Requirements

The c riteria for redesignating an area from nonattainment to attainment were discussed

in Section I of this document. Following is a review of the criteria described above as it pertains

to attainment of the standard, the emissions inventories, modeling, and motor vehicle emissions budgets.

B. Monitored Attainment

CAA section 107(d)(3)(E)(i) requires that we determine that the area has attained the applicable NAAQS. Generally, EPA determines whether an area’s air quality is meeting the 24

- hour PM 10 

### NAAQS based upon complete, 12 , 13 

### quality

- assured, and certified data gathered at established state and local air monitoring stations (SLAMS) i n the nonattainment area, and entered into the EPA Air Quality System (AQS) database. Data from air monitors operated by State, local, or Tribal agencies in compliance with EPA monitoring requirements must be submitted to AQS. These monitoring agencies cer tify annually that these data are accurate to the best of their knowledge. Accordingly, EPA relies primarily on data in AQS when determining
the attainment status of an area

. 14 

### EPA will also consider air quality data from other air monitoring stations in t he nonattainment area provided those stations meet the Federal monitoring requirements for SLAMS, including the quality assurance and quality control criteria in 40 CFR part 58, appendix A

. 15



### The 24

- hour PM 10 

### standard is attained when the expected number of days per calendar year with a 24

- hour average concentration above 150 μg/m3 , as determined in accordance
with 40 CFR appendix K , and average d over a three

- year period

, 16 

### is equal to or less than one.

12 For PM10, a “complete” set of data includes a minimum of 75 percent of the scheduled PM10 samples per quarter. See 40 CFR part 50, appendix K, section 2.3(a).

13 Because the annual PM10 standard was revoked effective December 18, 2006, this document discuss es only attainment of the 24

- hour PM10 standard. See 71 FR 61144; (October 17, 2006).

14 See 40 CFR 50.6; 40 CFR part 50, appendices J and K; 40 CFR part 53; and, 40 CFR part 58, appendices A, C, D, and
E.

15 See 40 CFR 58.14 (2006) and 58.20 (2007) 15 ; 71 FR 61236, 61242; (October 17, 2006). All valid data are reviewed to determine the area’s air quality status in accordance with 40 CFR part 50, appendix K.

16 See 40 CFR part 50, appendix K, section 2.1(a)Page 11 of 37



### For the purpose of determining attainment of the pr imary and secondary standards, particulate
matter shall be measured in the ambient air as PM 10 

### (particles with an aerodynamic diameter less than or equal to a nominal 10 micrometers) by a reference method based on 40 CFR appendix J and designated in accord ance with 40 CFR part 53 of this chapter, or an equivalent method designated in accordance with 40 CFR part 53

. 17



### According to 40 CFR Part 50 Appendix K, section 2.3 (b), to demonstrate attainment of
the 24

- hour standards at a monitoring site, the monitor must provide sufficient data (at least 75 percent complete) to perform the required calculations in 40 CFR part 50, appendix K 18 

### for expected exceedances. 19 

### The amount of data required varies with the sampling frequency, data capture rate, and the number of years of record. In all cases, three years of representative monitoring data that meet the 75 percent criterion discussed earlier should be utilized, if available. More than three years may be considered, if all additional representative years of
data m eeting the 75 percent criterion are utilized. Data not meeting these criteria may also suffice to show attainment; however, such exceptions must be approved by the appropriate Regional Administrator in accordance with EPA guidance

. 20



### In the South Coast PM 10 

### nonattainment area, the SCAQMD is the agenc y responsible for assuring that the area meets air quality monitoring requirements including its submit tal of
annual mon itoring network plans to EPA. The S C AQMD network plans describe the monitoring network ope rated by SCAQMD in the South Coast nonattainment area. These plans discuss the status of the air monitoring network, as required under 40 CFR 58.10. As shown in Figure B

- 1, SCAQMD operates 2 3 air quality monitoring stations for PM 10 

### in the South Coast Air Basin. As required by 40 CFR part 58, the SCAQMD conduct s annual reviews of the air quality monitoring
network and forward s these reviews to CARB and EPA for evaluation. Since 2007, EPA regularly

review s these annual plans for compli ance with the applicable reporting requirements in 40

17 See 40 CFR 50.6

.

18 See 40 CFR part 50, appendix K, section 2.3(b).

19 See 40 CFR part 50, appendix K, section 3.0(a)

.

20 See 40 CFR part 50, appendix K, section 2.3.Page 12 of 37 

## Figure B

- 1

. Ambient PM 10 

## Monitoring Locations in the South Coast Air Basin 21

21 Source: http://aqmd.gov/tao/AQ

- Reports/AQMonitoringNetworkPlan/AppendixA.pdfPage 13 of 37



### CFR part 58. Concerning PM 10 

### , EPA has found that the areas’ network plans submitted by SCAQMD meet the applicable requirements under 40 CFR part 58

. 22



### EPA also concluded from its Technical System Audit of the CARB Primary Quality Assurance Organization (PQAO)

, conducted during the spring of 2010, that the combined ambient air monitoring network operated by SCAQMD currently meets or exceeds the requirements for the minimum number of SLAMS for PM 10 

### in the South Coast nonattainment

area. 23 

### SCAQMD annually certifie s that the data it submits to AQS are complete and quality

assured. 24



### Since comprehensive monitoring began for PM 10 

### in the South Coast in the 19 6 0s, the area has seen a significant decline in ambient levels. Table B

- 1 displays the certified PM 10 

### data
for t he South Coast area for the years 2007

- 201 2 . All data have been certified by SCAQMD. As
shown in Table B

- 1, t here were a total of five missing quarters out of a possible total of 92 for
the 2009

- 2011 period. In total, there were 87 complete quarters for th is time period. To meet the 75 percent minimum completeness requirements

, the South Coast Monitoring network would require 18 sites to have 100 percent d ata completeness, with a total of 72 quarters complete . The South Coast Monitoring network exceeds this number of complete quarters. It should also be noted that the two sites (Perris and Fontana) with highest number of expected
exceedances in 2007 period both had 100 percent data completeness for all four quarters during the 2009

- 2011 period. 25



### In accordance with 40 CFR part 50, appendix K, 2.1 (a), the expected number of
exceedances for a 3

- year period is estimated by averaging the individual annual estimates for the past 3 years. The 3

- year average expected number of exceedances for these sites that

22 See Letter from Sean Hogan, Manager, Air Quality Analysis Office, U.S. EPA Region IX, to Dr. Chung Liu, Deputy Executive Officer, SCAQMD, dated May 30, 2008 ; Letter from Joe Lapka, Acting Manager, Air Quality Analysis Office, U.S. EPA Region IX, to Dr. Chung Liu, Deputy Execut ive Officer, SCAQMD, dated November 12, 2009 ; Letter from Matthew Lakin, Manager, Air Quality Analysis Office, U.S. EPA Region IX, to Dr. Chung Liu, Deputy Executive Officer, SCAQMD, dated November 1, 2010 ; and Letter from Matthew Lakin, Manager, Air Qual ity Analysis Office, U.S. EPA Region IX, to Dr. Chung Liu, Deputy Executive Officer, SCAQMD, dated November 1, 2011.

23 Technical System Audit Report, South Coast Air Quality Management District , April 13

– April 16, 2010, Conducted by Air Quality Analysis Office and Quality Assurance Office, US EPA Region 9, 75 Hawthorne Street

, San Francisco, California 94105, March 2011.

24 See, e.g., Letter, Chung Liu, Ph.D., Deputy Executive Officer Science and Technology Advancement, South Coast Air Quality M anagement District, to Jared Blumenfeld, Regional Administrator, U.S. EPA Region IX, certifying calendar year 2011 ambient air quality data and quality assurance data, May 1, 2012.

25 See EPA, Air Quality System Design Value Report s dated December 18, 201 2

– January 2, 2013 in the docket for today’s action.Page 14 of 37 

### Table B.1. South Coast Air Basin PM 10 

### Expected Exceedances (EE) and Completeness, 2007

- 201 2

Site AQS ID 2007 2008 2009

Ann
EE 3

- year EE Comp quart Ann

EE 3

- year

EE Comp quart Ann

EE 3

- year

EE Comp quart

Azusa 060370002 6.1 2 4 0 2 3 0 2 3 Burbank 060371002 0 0 1 0 0 4 0 0 4 Glendora 060370016 0 0 4 0 0 2 LAX Hastings 060375005 0 0 4 0 0 4 0 0 4 Los Angeles

– Main St. 060371103 0 0 4 0 0 4 0 0 4

North Long Beach 060374002 6.1 2 4 0 2 4 0 2 4

Santa Clarita 060376012 6.1 2 4 0 2 4 0 2 4 South Long Beach 060374004 0 0 1 0 0 4 0 0 4

Anaheim 060590007 6.1 2 4 0 2 4 0 2 4 Mission Viejo 060592022 0 0 4 0 0 4 0 0 4 Banning Airport 060650012 0 0 3 0 0 4 0 0 4

Lake Elsinore 060659001 0 0 4 0 0 4 Mira Loma (Van Buren) 060658005 0 0 4 0 0 4 0 0 4

Norco 060650003 6.1 2 4 0 2 4 0 2 4 Perris 060656001 29.1 9.7 3 0 9.7 3 0 9.7 4 Site AQS ID 2007 2008 2009

Ann EE 3

- year

EE Comp quart Ann EE 3

- year

EE Comp

quart Ann EE 3

- year EE Comp

quart

Azusa 060370002 6.1 2 4 0 2 3 0 2 3 Burbank 060371002 0 0 1 0 0 4 0 0 4 Glendora 060370016 0 0 4 0 0 2 LAX Hastings 060375005 0 0 4 0 0 4 0 0 4 Los Angeles

– Main St. 060371103 0 0 4 0 0 4 0 0 4 North Long Beach 060374002 6.1 2 4 0 2 4 0 2 4 Santa Clarita 060376012 6.1 2 4 0 2 4 0 2 4 South Long Beach 060374004 0 0 1 0 0 4 0 0 4 Anaheim 060590007 6.1 2 4 0 2 4 0 2 4 Mission Viejo 060592022 0 0 4 0 0 4 0 0 4 Banning Airport 060650012 0 0 3 0 0 4 0 0 4 Lake Elsinore 060659001 0 0 4 0 0 4 Mira Loma (Van Buren) 060658005 0 0 4 0 0 4 0 0 4
Norco 060650003 6.1 2 4 0 2 4 0 2 4 Perris 060656001 29.1 9.7 3 0 9.7 3 0 9.7 4 Riverside (Magnolia) 060651003 Rubidoux 060658001 3.1 1 4 0 0 4 0 1 4 Crestline 060710005 0 0 3 0 0 1 0 0 3
Fontana 060712002 13.2 4.4 4 0 4.4 4 0 4.4 4 Ontario Fire Station 060710025 6.1 2 4 0 2 4 0 2 4 Redlands 060714003 0 0 4 0 0 4 0 0 4 San Bernardino 060719004 6.1 2 4 0 2 4 0 2 4 Upland 060711004 0 0 4 0 0 4Page 15 of 37 

### Table B.1. South Coast Air Basin PM 10 

### Expected Exceedances (EE) and Completeness, 2007

- 201 2 (continued)

26 2012 air quality monitoring data and completeness data have not been certified.

Site AQS ID 2010 2011 2012 26

Ann EE 3

- year

EE Comp quart Ann EE 3

- year

EE Comp

quart Ann EE 3

- year EE Comp

quart

Azusa 060370002 0 0 4 0 0 4 0 0 NA Burbank 060371002 0 0 4 0 0 4 0 0 NA Glendora 060370016 0 0 3 0 0 4 0 0 NA LAX Hastings 060375005 0 0 4 0 0 4 0 0 NA Los Angeles

– Main St. 060371103 0 0 4 0 0 4 0 0 NA North Long Beach 060374002 0 0 4 0 0 4 0 0 NA Santa Clarita 060376012 0 0 4 0 0 4 0 0 NA South Long Beach 060374004 0 0 4 0 0 4 0 0 NA Anaheim 060590007 0 0 4 0 0 4 0 0 NA Mission Viejo 060592022 0 0 4 0 0 4 0 0 NA Banning Airport 060650012 0 0 4 0 0 4 0 0 NA Lake Elsinore 060659001 0 0 4 0 0 4 0 0 NA Mira Loma (Van Buren) 060658005 0 0 4 0 0 4 0 0 NA
Norco 060650003 0 0 4 0 0 4 0 0 NA Perris 060656001 0 0 4 0 0 4 0 0 NA Riverside (Magnolia) 060651003 0 0 4 0 0 NA Rubidoux 060658001 0 0 4 0 0 4 0 0 NA Crestline 060710005 0 0 4 0 0 4 0 0 NA
Fontana 060712002 0 0 4 0 0 4 0 0 NA Ontario Fire Station 060710025 0 0 4 0 0 4 0 0 NA Redlands 060714003 0 0 4 0 0 4 0 0 NA San Bernardino 060719004 0 0 4 0 0 4 0 0 NA Upland 060711004 0 0 4 0 0 4 0 0 NAPage 16 of 37



### include the year 2007 (e.g. 2007

- 2009), all have at least two expected exceedances. South Coast began attain ing the PM 10 

### standard in the year 2008. The first year where the 3

- year average expected number of exceedances is attaining is 2010 (i.e. for the 3

- year p eriod 2008

- 2010). Therefore, a nnual PM 10 

### levels in South Coast are below the standard with no or zero expected exceedances for the 200 8

- 2011 period at all sites in the South Coast nonattainment

are a for th e most recent 3

- year period of certified, qualit y

- assured data. 27



### We received a comment related to monitoring data from the South Coast Air Quality Management District, which is addressed in Section III. Response to Comments.

C. Attainment Inventory

Section 172(c)( 3) of the CAA requires plan submittals to include a comprehensive, accurate, and current inventory for the base year from all sources in the nonattainment area. In demonstrating maintenance in accordance with CAA section 175A and the Calcagni memo, 28



### the St ate should provide an attainment emissions inventory to identify the level of emissions in the area sufficient to attain the NAAQS. Where the State has made an adequate demonstration that air quality has improved as a result of the SIP, the attainment inve ntory should generally

contain actual emissions at the time the area attained the standard. The inventory should also include direct and secondary PM 10 

### emissions, and all stationary , area and mobile sources of

emissions.
In evaluating the State’s inventor y, EPA reviewed the following documents:

 South Coast Air Quality Management District

, Final PM 10 

### Redesignation Request and Maintenance Plan For the South Coast Air Basin, December, 2009

, Attachment C

.

 Chapter 3, Base Y

ear and Future Emissions, Introduction, Emission Inventories, Base Year Emissions, Future Emissions, Top Ten Source Categories (2002, 2014, 2023)

27 See EPA, Air Quality System Design Value Report s dated December 18, 2012

– January 2, 2013 in the docket for today’s action. 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 24

- hour PM10 NAAQS are found in 40 CFR 50, Appendix N, Section 1(c)(2).

28 “Procedures for Processing Request to Redesignate Areas to Attainment,” John Calcagni, Director, Air Quality Management Division, EPA Office of Air Quality Planning and Standards, September 4 , 1992

.Page 17 of 37 

###  South Coast Air Quality Management District

, Final 2007 AQMP, Appendix III,
Base and Future Year Emission Inventories

, June 2007

.

 California Environmental Protection Agency, Air Resources Board, Staff Report, Analysis of the South Coast A ir B asin PM 10 

### R edesignation Request, M aintenance Plan, and Conformity Budgets. February 22, 2010.

Table C

- 1 depicts the annual average day baseline emissions inventories for PM 10 

### , PM 2.5 

### , NOx,

VOC and SOX as presented in the 2009 South Coast PM 10 

### Redesignation Request and
Maintenance Plan for the years 2002 through 2030

. The District estimates that 56% of the total mass of average peak concentrations of PM 10 

### is attributable to PM 2.5 

### and 44% to coarse PM (fugitive dust)

. 29 

### Table C

- 2 provides a detailed breakout of the baseline attainment inventory
for the PM 10 

### emission subcategories. In the South Coast, the majority of daily PM 10 

### emissions
are estimated to come from re

- entrained road dust from paved and unpaved roads at 133.7 tons per day (47.6% of total emissions) in 2010. The District is using the year 2010 as the maintenance plan base year. EPA finds 2010 to be an appropriate base year because it is one of the years in the most recent three

- year periods (2008

- 2010, 2009

- 2011, and 2010

- 2012) in
which attainment of the PM 10 

### NAAQS was monitored.

As depicted in Table C

- 2, f uture PM 10 

### emissions are projected to nominally increase
from 2002 to 2030 (primari ly due to growth in the construction/demolition source categories ), from an estimated 274.7 tons per day in 2002 to an estimated 329.6 tons per day in 2030

. 30


### Overall, the PM 10 

### baseline emissions inventory will increase approximately seven (7) percent
from 2010 to 2020 and ten (10) percent from 2020 to 2030

. 31



### Based on our review of the 2009 South Coast PM 10 

### Redesignation Request and
Maintenance Plan , we find that the emissions inventories in the plan are comprehensive

, 32 

### in that they include estimates of PM 10 

### and its precursors from all of the relevant source categories.

29 See 2009 South Coast PM 10 Plan , p. 5.

30 See 2009 South Coast PM 10 Plan, p. 22.

31 See 2009 South Coast PM 10 Plan , p. 20.

32 EPA's primary guidance in evaluating these inventories is the document entitled, “PM 10 Emissions Inventory Requirements,” EPA, OAQPS, EPA

- 454/R

- 94

- 033 (September 1994) which can be found at: http://www.epa.gov/ttn/chief/eidocs/pm10eir.pdf

.Page 18 of 37



### While 2010 is the appropriate attainment plan base year, CAA Section 175A states that a request for redesignation of a nonattainment area shall provide for the maintenance of the NAAQS for at least 10 years after the redesignation. EPA expects to act on the South CoastPage 19 of 37 

### Table C

- 1. Annual Average Day Attainment Baseline Emissions Inventory (tons per day)

Pollutant 2002 2006 2008 2010 2011 2012 2014 2020 2023 2030

PM 10 

### 274.7 282.8 277.5 280.9 283.0 284.8 288.7 300.3 307.8 329.6

PM 2.5 

### 99.1 104.2 101.5 101.4 101.5 101.6 101.6 103.2 105.2 113.6

NOx 1093.2 970.7 853.7 774.7 742.9 711.6 653.6 525.2 506.4 511.8

VOC 844.2 695.9 608.0 572.4 559.4 547.9 527.7 498.5 496.0 508.4

SOx 53.3 54.8 40.9 39.2 40.1 40.7 42.8 51.4 55.1 71.7Page 20 of 37 

### Table C

- 2

. Annual Average Day Attainment Emissions Inventory for PM 10 

### Sources (tons per day)

Category 2002 2006 2008 2010 2011 2012 2014 2020 2023 2030

Stationary

– Point

sources 21.1 20.1 17.1 17.3 17.4 17.6 17.9 18.9 19.5 20.9

Construction and Demolition 39.9 46.9 49.8 52.9 54.3 55.8 58.7 66.0 69.7 78.9

Entrained Road Dust/Paved 125.4 123.5 122.3 123.4 124.0 124.5 125.8 129.3 131.1 135.2

Entrained Road Dust/Unpaved 13.6 11.5 10.3 10.3 10.3 10.3 10.3 10.2 10.2 10.2

Farming Operations 0.8 0.7 0.6 0.6 0.6 0.6 0.5 0.4 0.4 0.3

Fugitive Windblown
Dust 2.8 2.4 2.3 2.2 2.2 2.1 2.0 1.8 1.7 1.6

Other Area Sources 23.3 28.8 29.4 30.0 30.3 30.6 31.2 32.6 33.3 35.0

On

- road Mobile Sources 24.8 26.5 24.9 24.3 24.3 24.2 24.0 23.6 23.6 24.7

Off

- road Mobile Sources 23.1 22.5 20.7 19.9 19.6 19.2 18.4 17.4 18.1 22.7

Total PM 10 

### 274.7 282.8 277.5 280.9 283.0 284.8 288.7 300.3 307.7 329.6Page 21 of 37



### AQMD request for redesignation in 2013, therefore the maintenance period is anticipated to last through at least the year 2023. The district has provided inventories through the year

2030. In conclusion, EPA finds that the selection of 2010 as the attainment year inventory and 2030 for the maintenance year inventory is appropriate since 2010 is one of the years the area was determined to have attained, and the plan demonstrates maintenance of the standard through 2 030. We have reviewed the plan’s estimated attainment year emission inventory and determined that it is current, accurate and comprehensive, and meets EPA guidance and the CAA. Therefore we are approv ing the 2010 inventory, which also serves as the mainten ance plan’s attainment year inventory, under section 172(c) of the CAA.

We did not receive any comments on our proposed approval of the emissions inventory.

D. Modeling Demonstration of Maintenance of the NAAQS for 10 Years After Redesignation

Section 175A of the CAA requires a demonstration of maintenance of the NAAQS for 10 years after redesignation. A state generally may demonstrate maintenance of the NAAQS by either showing that future emissions of a pollutant or its precursors will not exceed the level of the attainment inventory, or by modeling to show that the future anticipated mix of sources and emission rates will not cause a violation of the NAAQS. For this plan, the state chose the second option and demonstrated maintenance of the 24

- hour PM 10 

### NAA QS by modeling to show that the future anticipated mix of sources and emission rates will not cause a violation of the NAAQS in the South Coast Air Basin.
In evaluating the State’s attainment demonstration modeling, EPA reviewed the following documents:

 South Coast Air Quality Management District, Final PM 10 

### Redesignation Request and Maintenance Plan For the South Coast Air Basin, December, 2009

, Attachment C

.

 South Coast Air Quality Management District

, Final 2007 AQMP, Appendix V, Modeling and Attainment Demonstrations, June 2007.

 U.S. Environmental Protection Agency, Region 9, Final Technical Support Document and Response to Comments, Final Rulemaking Action on the South Coast 2007 AQMP for PM 2.5 

### and the South Coast Portions of the Revised 2007 State Strategy

.Page 22 of 37 

###  U.S. Environmental Protection Agency

, Office of Air Quality Planning and Standards, PM 10 

### SIP Development Guideline, EPA

- 450/2

- 86

- 001, June 1987

.

 U.S. Environmental Protection Agency

, Guideli ne on Air Quality Models , 40 CFR Part 51 Appendix W

. EPA guidance recommends use of use of receptor and dispersion models in
combination. 33 

### In regulatory applications, dispersion models have been used in conjunction with receptor models to attribute source (or source category) contributions. 34 

### For this plan, the
state demonstrated maintenance of the 24

- hour PM 10 

### NAAQS by a combination of techniques, including dispersion modeling, and primary and precursor contribution based on filter analysis.

The state ’s analysis projected the maximum future year PM 10 

### concentration for each of the four counties in the South Coast Air Basin. The highest maximum concentration observed during each of the years 2005, 2006, and 2007 at any ambient air quality monitoring sit e in the county was selected to represent the potential peak concentration for the county. These values, and the site where the value was measured, are shown in Table D

- 1 below.

Table D

- 1. PM 10 

### Peak Concentrations

County Highest Site Peak Year Peak PM 10 

### 2005

- 2007 μg/m 3 

### Los Angeles South Coastal LA County

- 2 2005 131 Orange Central Orange County 2006 104 Riverside Mira Loma 2007 142 San Bernardino Central San Bernadino

- 1 2006 142

The future PM 10 

### levels were modeled in a two

- part analysis, using separate methods for projecting the future values of the fine fraction (PM 2.5 

### ) and the coarse fraction ( PM 2.5 

### to PM 10 

### )
fraction of PM 10 

### . First, the fine and coarse fractions for each of the site

- specific PM 10 

### peak

concentrations were determined by a county averaged ratio of the PM 2.5 

### and PM 10 

### maximum
concentrations. These values are listed in Table D

- 2
, below.

33 Chapter 4.0

, Air Quality Modeling for PM10
, PM10 SIP Development Guideline , EPA

- 450/2

- 86

- 001, June 1987

.

34 40 CFR Part 51 Appendix W, 5.2.2.2, PM

– 10

.Page 23 of 37



### Table D

- 2. County L evel Estimate of Fine and Coarse PM 10 

### Peak Concentration

County Peak PM 10



### 2005

- 2007

μg/m 3 

### County specific

PM 2.5 

### / PM 10 

### ratio Fine Mass

μg/m 3 

### Coarse Mass

μg/m 3



### Los Angeles 131 0.603 79 52 Orange 104 0.595 62 42 Riverside 142 0.573 81 61 San Bernardino 142 0.486 69 73

For the PM 2.5 

### fraction of PM 10 

### , the modeling demonstration was based on applying site

specific relative reduction factors (RRFs) for each of the future years to the fine mass fraction.
The relative reduction factors which were generated from the regional modeling analysis for

2007 PM 2. 5 

### Plan , which accounted for the chemical formation of secondary particulate matter. 35



### EPA’s evaluation of the 2007 PM 2.5 

### modeling is provided in the Final Technical Support Document and Response to Comments, Final Rulemaking Action on the South Coast 2007 AQMP for PM 2.5 

### and the South Coast Portions of the Revised 2007 State Strategy

. 36 

### The Air Quality
Model Selection

, Episode Selection

, Domain Size and Spatial Resolution

, Initial and Boundary
Conditions

, Meteorological Model , and Air Quality Model Performance for the regional PM 2.5 

### modeling are discussed in detail in that document.

The PM 2.5 

### RRFs were calculated from the regional modeling, based on the sites listed in
Table D

- 3 below , for each of the years 2010, 2011, 2012, 2014, 2020, 2023, and 2030. The county specific relative reduction factor for each ye ar was multiplied by the county

- specific fine

mass peak concentration . The projected fine mass for each county for the years 2023 and

2030 are shown in Table D

- 4 Projected 24 hour PM 10 

### (μg/m 3 

### ) for 2023 and 2030

.

35 Final 2007 AQMP, Appendix V, Modeling and Attainment Demonstrations, June 2007, South Coast Air Quality Management District

. 36 Final Technical Support Document and Response to Comments, Final Rulemaking Action on the South Coast 2007 AQMP for PM 2.5 and the South Coast Portions of the Revised 2007 State Strategy, Section II. Evaluation of the South Coast 2007 AQMP for PM 2.5 , B. Air Quality Modeling

.Page 24 of 37



### Table D

- 3. County L evel Estimate of Relative Reduction factors for Fine PM 10 

### Peak Concentrations

.

County Sites used for development of Relative Reduction Factors

Los Angeles Los Angeles, Long Beach, Burbank, Compton, Wilmington Orange Anaheim Riverside Rubidoux San Bernardino Fontana

Table D

- 4. Projected 24

- hour PM 10 

### (μg/m 3 

### ) for 2023 and 2030

County 2023 2030

Fine Coarse Total
Mass Fine Coarse Total
Mass Los Angeles 47 56 103 49 60 109 Orange 36 45 81 37 48 86 Riverside 53 66 118 54 70 125 San Bernardino 50 79 128 52 84 136

The future levels of the “coarse” fraction ( PM 2.5 

### - PM 10 

### ) of the PM 10 

### m ass were projected by emissions

- based rollback. Estimation of the future

- year PM 10 

### coarse particulate concentration was conducted by multiplying the coarse mass peak concentration by the projected changes in the emission level. Baseline PM 10 

### emissions for 2020, 2023 and 2030 show increases of 5, 8, and 15 percent respectively over 2005 levels. The projected coarse mass for each county for the years 2023 and 2030 are shown in Table D

- 4 below.

The projected total PM 10 

### mass was estimated for each of the future years by adding the
fine mass fraction to th e coarse mass fraction. The county

- specific projected PM 10 

### levels for
2023 and 2030 are also shown in the Table D

- 4. 37



### The reduction in particulate matter precursor emissions results in a reduction in the
levels of PM 10 

### , demonstrating maintenance of the PM 10 

### NAAQS for the South Coast Air Basin for ten years after redesignation , and beyond

. 38 

### The modeled PM 10 

### levels are below the 24

- hour

37 Final 2007 AQMP, Appendix V, Modeling and Attainment Demonstrations, June 2007, South Coast Air Quality Management District

. 38 24 hour average PM10 values were projected for the years 2010, 2011, 2012, 2014, 2020, 2023, and 2030. Pla n p. 69

.Page 25 of 37



### PM 10 

### NAAQS level of 150 μg/m3 for each of the future modeled years for each of the counties
in the South Coast Air Basin in cluding the year 2023, and beyond (2030)

.

EPA finds that the methodology used in the plan to project the levels of PM 10 

### for 10 years and beyond is reasonable and meets EPA ’s guidance. EPA finds the forecasted decreases in 24

- hour

PM 10 

### levels, based on the decrease in particulate matter precursor (NOx and VOC) emissions, are consistent with the control measures that are scheduled for implementation. Based on our review of the information presented in the 2009 South Coast PM 10 

### Redesignat ion Request and
Maintenance Plan , we find that the State has shown that attainment of the PM 10 

### NAAQS will be maintained in the South Coast Air Basin for at least ten years after redesignation

. We did not receive any comments on our proposed approval of the maintenance demonstration and modeling.

E. Transportation Conformity

1. Requirements for Transportation Conformity and Motor Vehicle Emissions Budgets

CAA section 176(c) requires Federal actions in nonattainment and maintenance areas to conform to the SIP’s goals of eliminating or reducing the severity and number of violations of the NAAQS and achiev e expeditious attainment of the standards. Conformity t o the SIP’s goals 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 (RTP) and transportation improvement programs (TIP) conform to the applicable SIP. This demonstration is typically done by showing that estimated emissions from existing and planned highway and transit systems are less than or equal to the motor vehicle emissions budgets (budgets) contained in all control strategy SIPs. An attainment, maintenance, or reasonable further progress ( RFP ) SIP should include budgets for the attainment year, each required RFP year or last year of the maintenance plan, as appropriate. Budgets are generally established for specific years and specific pollutants or precursors.Page 26 of 37



### PM 10 

### maintenance plans should identify budgets for direct PM 10 

### and PM 10 

### precursors. All direct PM 10 

### SIP budgets should include direct PM 10 

### motor vehicle emissions from tailpipe, brake wear, tire wear

, and re

- entrained pa v ed and u n paved road dust. A state must also
consider whether construction

- related dust is a significant contributor and should be included
in the direct PM 10 

### budget

. 39



### MPOs may use budgets in a submitted but not yet approved SIP

, only if EPA has first determined that the budg ets are adequate. Budgets are deemed adequate and may eventually
be approved if t he submittal meet s the conformity adequacy requirements of

4 0 CFR § 93.118(e)(4) and is approvable under all pertinent SIP requirements. In addition, the budgets must reflect all of the motor vehicle control measures contained in the attainment and
RFP demonstrations. 40



### 2. Motor Vehicle Emissions Budgets in the 2009 South Coast PM 10 

### Redesignation Request and
Maintenance Plan

The motor vehicle emissions budgets for the South Co ast are summarized in Table E

- 1

. 2009
South Coast PM 10 

### Redesignation Request and Maintenance Plan , submitted on April 28, 2010

, include s a set of PM 10 

### budgets for the years 2010, 2020 and 2030 for directly emitted PM 10 

### , VOC (in California, also known as ROG)

, 41 

### and NOx

. 42

, 43
, 44 

### CARB revised the budgets in the

39 See 40 CFR § 93. 122

. 40 See 40 CFR § 93.118(e)(4)(v).

41 The California Air Resources Board (CARB) uses the term reactive organic gases (ROG) for planning and inventory purposes and uses it synonymously with its own definition of “volatile organic compound” for regulatory purposes. The value of ROG for inventory purposes is derived by multiplying the reported Total Organic Gases (TOG) by the Fraction of Reactive Organic Gases (FROG). Each source category is keyed to one of several hundred available chemical speciation profiles. For each category, the FROG value i s calculated as the weight fraction of those species designated by the ARB as reactive in the speciation profile applicable to the category. CARB’s organic gas speciation profiles are available for download at http://www.arb.ca.gov/ei/speciate/speciate.htm . EPA defines and uses the term volatile organic compounds (VOC), which relies upon a list of exempted compounds having negligible photochemical reactivity

, that is periodically updated. EPA cod ifies its definition of VOC at 40 CFR part 51 section 51.100, Definitions. Although some differences existed in the past between California’s use of the term “ROG” and EPA’s definition of “VOC”, the two terms are now nearly identical in that CARB’s curren t definitions for ROG and VOC include a list of low

- reactive organic compounds which have been exempted by EPA. Source: Definitions of ROG and TOG (As of January 2009) ( See http://www.arb.ca.gov/ei/speciate/voc_rog_dfn_1_09.pdf)

42 See CARB Resolution 10

- 21 and the 2010 CARB Staff Report, “Analysis of the South Coast Air Basin PM10 Redesignation Request, Maintenance Plan,” and supplementary information, which is an update to the Final PM10 Redesignation Request and Maintenance Plan for the South Coast A ir Basin (South Coast PM10 Plan)

.

43 S ee letter , James N. Goldstene, Executive Officer, to Jared Blumenfeld, Regional Administrator, EPA Region 9, dated April 28, 2010 , transmitting the 2009 South Coast PM10 Redesignation Request and Maintenance Plan, CARBPage 27 of 37



### 2009 South Coast PM 10 

### Redesignation Request and Maintenance Plan in response to EPA comments. Additional information associated with the motor vehicle emission budget
calculations is provided in a technical analysis accompanying a March 19 , 2013 letter from
SCAQMD to EPA

. 45



### Table E

- 1

. 2009 South Coast PM 10 

### Redesignation Request and Maintenance Plan Motor Vehicle Emissions Budgets as submitted in the Final South Coast PM 10 

### Redesignation Request and Maintenance Plan (Annual Average tons per day)

Emissions Budget 2010 2020 2030

PM 10 

### 159 164 175

NOx 372 180 116

ROG 182 110 81

The details for each component of the budgets for the South Coast are shown in Table E

- 2
and are comprised of direct on

- road mobile source emissions

, road construction emissions, fugitive emissions from paved and unpaved roads, and safety margins . The budgets include a

Board Resolution 10

- 21 adopting the 2009 South Coast PM 10 Maintenance Plan and Transportation conformity budgets at the CARB Board hearing.

44 T he South Coast Air Quality Management District ( SCAQMD ) adopted its Final PM10 Redesignation Request and
Mai ntenance Plan for South Coast Air Basin ( 2009 South Coast PM 10 Plan) on January 8, 2010. Shortly before plan adoption, SCAQMD developed revised budgets for the plan based on U.S. EPA (EPA) comments that the budgets only include emission reductions from a dopted control measure s . Thus SCAQMD removed the budgets prior to Board consideration. SCAQMD and the California Air Resources Board (CARB) revised the budgets prior to CARB’s adoption of the South Coast PM10 Plan. Concurrent with its 45

- day notice for 2009 South Coast PM 10 Plan consideration on February 22, 2010, CARB posted the revised budgets for a 30

- day public review on February 22,
2010 . CARB approved both the budgets and the South Coast PM10 Plan as a revision to the California State Implementati on Plan (SIP) at a public hearing on March 25, 2010.

45 See Letter from Elaine Chang, Deputy Executive Officer, SCAQMD to Deborah Jordan, Director Air Division, EPA, Region 9, and accompanying technical analysis (“ South Coast Air Basin Paved Road Dust Calc ulation PM10 Based on 2011 AP

- 42 Default Silt Loading and EMFAC2011 VMT ”), dated March 19, 2013

.Page 28 of 37



### safety margin

, and even with this safety margin

, the total emissions in the maintenance plan

are less than the emissions carrying capacity calculated for the attainment year. A state mayPage 29 of 37 

### Table E

- 2

. Transportation Conformity Budgets Detail for PM 10

(Annual Average tons per day)

2010 2020 2030

ROG NOx 

### PM 10 ROG NOx 

### PM 10 ROG NOx 

### PM 10 On

- Road Emissions from EMFAC 2007 174.3 386.4 23.1 107.1 191.1 22.0 79.4 127.7 22.6

Paved Road Dust

__ __ 70.6 __ __ 73.4 __ __ 78.8

Un

- paved Road Dust

__

__ 10.3 __ __ 10.2 __ __ 10.2

Road Construction Dust

__ __ 2.4 __ __ 2.4 __ __ 2.5
Adjustments to Baseline*

- 0.3

- 14.7

- 0 .2

- 1.1

- 11.8

- 0.3

- 2.1

- 11.7

- 0.6 Safety Margin 7.0 __ 52.8 4.0 __ 56.9 3.0 __ 61.4

Net Inventory 181.1 371.1 159.0 110.0 179.3 163.6 80.3 116.0 174.9

Conformity Budget** 182 372 169 110 180 164 81 116 175

* Reductions from adopted rules not reflected in EMFAC ** Budget is obtained by rounding up to the nearest ton.

Notes: Paved and unpaved road dust is calculated by the South Coast AQMD and is reported in Table 3

- 2 in the adopted plan, and revised in March 19 , 2013 letter Road construction dust is a component of the Construction/Demolition category in T able 3

- 2 in the adopted plan. Vehicle activity data used in EMFAC was received from SCAG in April 2009, and reflects SCAG's 2008 RTP, Amendment 1. The safety margin is to account for additional directly emitted PM 10 from anticipated growth in VMT. The ado pted maintenance plan analyzes the impact of an additional 20 tons per day of PM 10 beyond the 2007 AQMP/SIP baseline and concludes that the Basin will continue to maintain the PM 10 stan dard. An additional 5 tons of PM10 is added to account for this antic ipated VMT growth while setting an emissions budget that ensures continued maintenance of the standard. An additional 7, 4 and 3 tons of ROG is added in 2010, 2020 and 2030, respectively to account for increased ROG emissions fro m anticipated growth in VMT

. Analysis by the South Coast District concluded that these budgets are consistent with continued maintenance of the standard a nd allowed for additional safety margin emissions. See the Supplementary Information for a discussion of the South Coast District analysis. Columns may not add due to rounding

.Page 30 of 37



### choose to apply a safety margin under our transportation conformity rule so long as such margins are explicitly quantified in the applicable plan and are shown to be consistent with attainment or maintenance of the NAAQS (whichever is relevant to the particular plan). 46 

### In this instance, the safety margin has been explicitly quantified and shown to be consistent with
continued maintenance of the PM 10 

### NAAQS in South Coast PM 10 

### nonattain ment area through the applicable maintenance period

, through 2030

. 47



### The budgets were developed using emission factors generated by CARB’s EMFAC2007 48


### model for direct emissions, and EPA’s AP

- 42 was used to develop emissions for the fugitive and
construction emissions. 49 

### The paved road emissions were originally calculated using the 2006
version of AP

- 42 as a component of the 2007 South Coast Air Quality Management Plan ( AQMP ) emissions inventory projected to 2010, 2020 and 2030. The calculation r elied on a California profile of silt loading, weather, roadway centerline miles and Vehicle Miles Traveled ( VMT ) growth. 50



### EPA released an update to AP

- 42 in January 2011 which revised the equation for estimating paved road dust emissions based on an up dated regression that included new emission tests
results . The SCAQMD staff conducted a technical analysis that accompanied the March 19,
2013 letter from SCAQMD to EPA 51 

### of their paved road dust emission projections using the updated equation and the late st planning assumptions to ensure that the budgets are consistent with the currently approved modeling tools and data. In the analysis

, SCAQMD applied the default values of silt loading for freeways, arterial, collectors and local roads of 0.03, 0.06, 0.06 and 0.2 grams per meter squared ( g/m 2 ) 

### , respectively and a default PM 10 

### particle size multiplier of 0.0022 pounds per VMT ( lbs/VMT )

. VMT estimates were extracted

46 See 40 CFR 93.124(a).

47 See the 2009 South Coast PM 10 Plan, page 25, Table 3

- 5 and Appendix

- 4.
48 EMFAC ( EM ission FAC tor) is California’s model for estimating emissions from on

- road vehicles operating in California. It is built on decades of vehicle testing and analysis, and is informed by DMV registration data, the Smog Check program, and many other data sources. EPA approved EMFAC2007 on January 18, 2008 (73 FR 3464). CARB’s latest release is EMFAC 2011 which EPA approved on March 6, 2013 (78 FR 14533).

49 AP

- 42, Compilation of Air Pollutant Emission Factors

, is a document published by EPA as the primary collection of EPA approved emission factor inf ormation. The emission factors have been developed and compiled from source test data, material balance studies, and engineering estimates. EPA has publishe d supplements and updates to the each of the chapters available in Volume I, Stationary Point and Ar ea Sources at the following web site: http://www.epa.gov/ttnchie1/ap42/

. 50 In the South Coast PM10 Plan, as adopted by the SCAQMD on January 8, 2010.

51 See Letter from Elaine Chang, Deputy Executive Officer, SCAQMD to Deborah Jordan, Director Air Division, EPA, Region 9, and accompanying technical analysis (“ South Coast Air Basin Paved Road Dust Calculation PM10 Based on 2011 AP

- 42 Default Silt Loading and EMFAC2011 VMT ”), dat ed March 19, 2013

.Page 31 of 37



### from the CARB ’s EMFAC2011 for 2010, 2020 and 2030. The technical analysis showed that the updated paved road dust emissions were less than the attainment inventory emissions of paved road dust for all years for which motor veh icle emission budgets were estimated in the original submittal. For example, in the technical analysis

, emissions of paved road dust in 2030 (done
with the latest AP

- 42 version and the updated silt loading factors and particle size multiplier)

were estimated to be 78.8 tpd. The 2009 South Coast PM 10 

### Redesignation Request and
Maintenance Plan demonstrates that the PM 10 

### NAAQS can be maintained with re

- entrained road dust emissions from paved roads at 135.2 tpd (see technical analysis in March 19, 201 3
letter ) . Therefore

, the revised future year emissions estimates resulting from the technical analysis are much lower (e.g. 56.4 tpd) than the levels that were shown as needed to attain and
maintain the PM 10 

### in the original analysis submitted by the SCAQ MD.

3. Final Action on the Budgets
We did not receive any comments on our proposed approval of the budgets in the PM 10 

### maintenance plan. In today’s action, EPA is approv ing the budgets in the 2009 South Coast PM 10 

### Redesignation Request and Maintenance Plan and therefore is reviewing the budgets against our adequacy criteria in 40 CFR § 93.318(a)(4) as part of our review of the approvability of the
submitted budgets. The results of this review are shown in the Table E

- 3 . EPA is not required under its Transportation Conformity rule to find budgets adequate prior to proposing approval
of them. As described in the Federal Register notice of proposed rulemaking, EPA notif ied the public that we review ed the adequacy of th e budgets and the public ha d 30 days to comment,
after which we would make a finding on the adequacy of the budgets.

We are approv ing the maintenance demonstration in the 2009 South Coast PM 10 

### Redesignation Request and Maintenance Plan

. As discussed above in Section C, Attainment Inventory , the motor vehicle emissions portions of these budgets (i.e., the evaporative and tailpipe emissions) were developed using the EMFAC2007 motor vehicle emissions factors, along with activity levels reflect ing current information provided by SCAG . T he fugitive emission estimates in the budgets are consistent with EPA’s AP

- 42 model and contain a safety margin consistent with maintenance of the standard for the maintenance period

. We are approv ing the

motor ve hicle emission budgets consistent with CAA section 176(c)(2)(A) and the adequacy criteria of 40 CFR 93.118(e)(4), includi ng consistency with the 2009 South Coast PM 10 

### Redesignation Request and Maintenance Plan emissions inventories, the motor vehicle contr ol

measure emission reductions used in the maintenance demonstration, and the reductions
needed for continued maintenance of the standa rd

.Page 32 of 37



### On the effective date of our final action, SCAG and the U.S. Department of Transportation will be required to use the revised budgets in transportation conformity determinations. Due to the formatting of the budgets (including adjustments to the baseline
emissions to account for additional reductio ns from control measures) CARB will need to provide SCAG with emission reductions associated with the control measures incorporated into the budgets for the appropriate analysis years in future conformity determinations so that they
can include these reduc tions pursuant to 40 CFR § 93.122. In addition, for these conformity determinations, the motor vehicle emissions from implementation of the transportation plan should be projected and compared to the budgets at the same level of accuracy as the budgets
in th is maintenance plan, for example emissions should be rounded to the whole number (e.g.

1 1 tpd).

### Table E.3

. Evaluation of the Motor Vehicle Emissions Budget for the Request for the Final PM 10 

### Redesignation and Maintenance Plan for the South Coast Air Basin

Adequacy Review Criteria (40 CFR Part 93) Is Criterion Satisfied? Y/N Reference in SIP Document/Comments

Sec. 93.118(e)(4)(i) The plan was endorsed by the

Governor (or designee) and was subject to a public hearing. Y Both the South Coast Air Quality Management District ( SCAQMD ) and the California Air Resources Board ( CARB ) satisfied applicable statutory and regulatory requirements for reasonable public notice and hearing prior to adoption and submittal of the Final PM 10 Redesignation Request and Maintenance Plan for the South Coast Air Basin ( 2009 South Coast PM 10 Redesignation Request
and Maintenance Plan ) and Motor Vehicle Emissions Budgets (budgets). SCAQMD approved the
2009 South Coast PM 10 Redesignation Request and Maintenance Plan at a public hearing on January 8, 2010 and transmitted Board Resolution 10

- 1 with the plan and other supporting documentation to CARB on January 15 , 2010. Shortly before plan adoption, SCAQMD developed revised budgets for the plan based o n U.S. EPA (EPA) comments that the budgets only include emission reductions from adopted control measure s . Thus SCAQMD removed the budgets prior to
Board consideration. SCAQMD issued “A Notice of Public Hearing”, made t he draft p lan available
on the Distr ict's website

, and published the notice in five local publications on October 21, 2009.

After the SCAQMD Board approv ed the plan on January 8, 2010 , CARB distributed a 45

- day notice
for the 2009 South Coast PM 10 Redesignation Request and Maintenance Plan consideration on February 22, 2010. Additionally, CARB posted the revised budgets for a 30

- day public review on February 22, 2010 . CARB approved both the budgets and the 2009 South Coast PM 10 Redesignation Request and Maintenance Plan as a revision to th e California State Implementation Plan (SIP) at a public hearing on March 25, 2010. See CARB Resolution 10

- 21. CARB received no comments on the plan.

The April 28, 2010 transmittal letter submitting the 2009 South Coast PM 10 Redesignation Request
and Maint enance Plan was sent to EPA by the CARB’s Executive Officer, James Goldstene, the Governor’s designee. Both the January 15 2010 and April 28 2010 submittals contain proof of publication and evidence that the SCAQMD and CARB public hearings were properly n oticed.Page 34 of 37

Sec. 93.118(e)(4)(ii) The plan was developed

through consultation with federal, state and local agencies; full implementation plan documentation was provided and EPA’s stated concerns, if any, were
addressed. Y Consultation with federal, state and local agencies was undertaken; this consultation took place
with the Southern California Association of Governments ( SCAG ) and an interag ency consultation working group. Members of the consultation group include: EPA, F HW A, FTA, CARB, C altrans,
SCAQMD , SCAG ( the area’s Metropolitan Planning Organization [ MP O] ) , and county transportation agencies . EPA received a copy of the draft South Coast PM 10 Redesignation Request and
Maintenance Plan on July 21 , 2009, and provided w ritten comments on August 18, 2009. The
South Coast AQMD addressed the comments by incorporating revisions into the final 2009 South
Coast PM 10 Redesignation Request and Maintenance Plan , dated December 2009. Revisions include: 1) an addition of emissions for 2008; 2) a revision of daily vehicle miles traveled (VMT) provided by CARB’s EMFAC2007 model; and 3) explanation of the relevancy of the 2002 base year.

The district also addressed EPA comments submitted previously by revising the original b udgets to only include emissions reduction resulting from control measures that were already adopted.

Sec. 93.118(e)(4)(iii) The motor vehicle emission

budget(s) is clearly identified
and precisely quantified. Y CARB’s Staff Report, Analysis of the South Coast Air Basin PM 10 Redesignation Request, Maintenance Plan, and Conformity Budgets , released to the public on February 22, 2010

, contains Table 4, Transportation Conformity Emissions Budgets for PM 10 in the South Coast Air Basin , wh ich clearly identifies and precisely quantifies the budgets and the methodology for the years 2010,
2020 and 2030.

Sec. 93.118(e)(4)(iv) The motor vehicle emissions

budget(s), when considered together with all other emission sources, is
consistent with applicable requirements for reasonable further progress, attainment, or maintenance (whichever is relevant to the given plan). Y EPA has determined that the budgets, when considered together with all other emission sources, are consistent with applicable r equirements for maintenance of the PM 10 National Ambient Air Quality Standard of 150 μ g/m 3 ( 24

- hour)

. Prior to the District’s Board hearing, the District revised the transportation conformity budgets in
the 2009 South Coast PM 10 Redesignation Request and Maintenance Plan to reflect U.S. EPA‘s comment that the budgets only include emission reductions from already adopted control measures. In Chapter 3 of the 2009 South Coast PM 10 Redesignation Request and Maintenance
Plan , a PM 10 modeling sensitivity analysis was conducted for the years 2010 through 2030 to evaluate the impact of adding 20 tons per day (tpd) of directly emitted PM 10 to the Basin baseline inventory. After consultation with the District and the metropolitan plannin g organization (MPO) for the region, the Southern California Association of Governments (SCAG), 5 tpd of directly

emitted PM 10 were added to the conformity budget for 2030 and 7 tpd, 4 tpd, and 3 tpd of ROG to the budgets for 2010, 2020, and 2030, respecti vely. Based on established modeling ratios, the additional ROG emissions translate to adding 1 tpd of PM 10 emissions of ROG equivalencyii. (rounding to whole tpd) for 2010, 2020, and 2030, respectively. Therefore, total additions for the 2030 budget are the e quivalent of 6 tpd of PM 10 . The additional 6 tpd of PM 10 represents only 30 percent of the 20 tpd PM 10 safety margin identified in the 2009 South Coast PM 10 Redesignation Request and Maintenance Plan . The 6 tpd of PM 10 facilitates anticipated growth while setting an emissions budget that ensures continued maintenance of the standard.

EPA released an update to AP

- 42 in January of 2011 which revised the equation for estimating paved road emissions based on an updated regression of emission tests. Th e SCAQMD staff
conducted additional technical analysis of their paved road emission projections using the updated AP

- 42 equation and the latest planning assumptions, to ensure that the mo tor vehicle emission budgets were sti ll consistent with the currently approved modeling tools and data and
the maintenance demonstration. The technical analysis showed that the updated paved road emissions provided a significant safety margin as compared to the attainment inventory emissions of paved road dust for all years for which motor vehicle emission budgets were estimate d, therefore the total motor vehicle emissions budgets are consistent with maintenance of the
standard.

Sec. 93.118(e)(4)(v) The plan shows a clear

relationship amon g the emissions budget(s), control
measures and the total emissions inventory. Y Emissions inventory estimates and modeling analyses are documented in Section 3 of the 2009
South Coast PM 10 Redesignation Request and Maintenance Plan . The attainment baseli ne emission inventories for all point, area and mobile sources are listed for PM 10 , PM 2.5 , NOx, VOC and SOX for the years 2002 (Inventory Base Year), 2006, 2008 2010, 2011, 2012, 2020, 2023 and 2030

. Section 3 also includes a detailed breakout of the updated baseline attainment inventory for the PM 10 emission subcategories, which includes emissions estimates from paved and unpaved entrained road dust. Budget estimates contained in the 2009 South Coast PM 10 Redesignation Request and
Maintenance Plan were not adopted on January 8, 2010 with the rest of the plan. However, the district developed and CARB posted to its website, revised budget estimates on February 22, 2010. These budget estimates, when con sidered together with adjustments made to the baseline inventories are consistent with and show a clear relationship to the emissions inventory contained
in Section 3 of the 2009 South Coast PM 10 Redesignation Request and Maintenance Plan . South Coast prov ided an explanation of budget adjustments made to reflect both a safety margin and the relative contribution from Reactive Organic Gases in a February 19, 2010 letter from Deputy Executive Officer, Elaine Chang to Lynn Terry, Deputy Executive Officer, Cali fornia Air Resources Board. All other adjustments to baseline inventories and 2020 and 2030 budget estimates for

PM 10 were minor and conform to the emissions inventory submitted in Section 3 of the 2009 SouthPage 36 of 37 Coast PM 10 Redesignation Request and Maintenan ce Plan

. Sec. 93.118(e)(4)(vi) Revisions to previously

submitted control strategy or maintenance plans explain and document any changes to any previous submitted budgets and control measures; impacts on point and area source emissions; any changes to established safety margins (see §93.101 for definition), and reasons for the changes (including the basis for any changes to
emission factors or estimates
of VMT. Y CARB submitted to EPA the draft South Coast PM 10 Redesignation Request and Maintenance Plan on July 21, 2009, and EPA provided written comments on August 18, 2009. South Coast finalized this plan in December 2009. South Coast made a number of editorial revisions to the plan, however, the most signific ant revisions were made to the budgets. Budgets contained in the both
the draft and final versions of the 2009 South Coast PM 10 Redesignation Request and Maintenance
Plan were revised. Prior to the District’s Board hearing on January 8, 2010 , the Distric t revised the transportation conformity budgets to reflect U.S. EPA‘s comment that the budgets only include emission reductions from already adopted control measures. The submitted budgets are contained
in Table E

- 1 of this report. In addition to the consi deration of the EPA’s comments, the 2030 budgets also include an additional 6 tpd safety margin to facilitate growth. The additional technical analysis performed by the SCAQMD, using the 2011 version of AP

- 42 showed that
additional emissions are available for inclusion in the safety margins for the motor vehicle emission budgets.

Sec. 93.118(e)(5) EPA has reviewed the State’s

compilation of public comments and response to comments that are required to be submitted with any implementation plan. Y Neither CARB nor SCAQMD received public comments on the 2009 South Coast PM 10 Redesignation Request and Maintenance Plan and Transportation Conformity Budgets.

## III. Response to Comments

EPA provided for a 30

- day public comment period on our proposed action. The comment period ended on May 8, 2013. We received one comment letter from the South Coast Air Quality Management District (SCAQMD or District) on May 8, 2013. 52 

### We respond to that
comment here.

Comment: SCAQMD strongly supports EPA’s proposed action. The District also commented that it submitted, through CARB, exceptional events packages requesting exclusion of monitoring data from multiple sites in the SCAQMD network from October 21, 2007 and July 5, 200 7 under EPA’s Exceptional Events Rule (72 FR 28612, May 22, 2007). The exceptional events requests were submitted to EPA by CARB on October 23, 2009 and December 22, 2009, respectively. The letter also requested EPA to acknowledge the requests if EPA did n ot evaluate these requests before taking final action on this proposal.

Response : EPA is not taking any action on the exceptional events requests cited in the District’s comment letter. It is not necessary for EPA to process those requests because this final action is based on monitored data occurring after the time of those requests. Therefore, whether we granted or denied the exceptional events requests concerning data from 2007 would not have any bearing on our action today.

52 See letter, Elaine Chang, DrPH, Deputy Executive Officer, South Coast Air Quality Management District, to Wienke Tax, US Environmental Protection Agency, Region IX, dated May 8, 2013, in the docket for today’s action.