# Air Resources Board Mary 

### D. Nichols, Chairman

1001 1 Street P.O. Box 2815 Linda S. Adams Sacramento, California 95812 www.arb.ca.gov Edmund G. Brown Jr. Acting Secretary for Governor Environmental Protection



### May 18,2011

ElizabethAdams, Deputy Director Air Division, Region 9 U.S. Environmental Protection Agency 75 Hawthorne Street San Francisco, California 94105 Dear Ms. Adams: On April 28,2011,the Air Resources Board (ARB or Board) approvedfor adoption a revisionto California's State Implementation Plan (SIP) for the federal particulate matter standard (PM2.5). Under separate cover,ARB is formally submitting the SIP revisionto the U.S. Environmental ProtectionAgency (U.S. EPA). Following the Board'sApril action, U.S. EPA staff requested additional explanation of information contained in the SIP revision. In responseto this request, ARB staff is providing the following: Attachment 1: lnformation that shows the emission inventory relationships among the detailed information in specific appendices: Appendix C, "Reasonable Further Progress Tables";Appendix Dl "Transportation Conformity Budgets";and the detailed methodology included inAppendix El "Additional Documentation." lnformation on howthese methodologies affect base year emissions is also discussed. Attachment 2: lnformation on attainment year contingency estimates contained in the adopted SIP revision, includingthe emission reductions between 2014 and 2015 that would be used for attainment year contingency. Attachment 3: lnformation on inter-pollutant trading ratios that depicts the relative effectiveness of reductions in different precursors contributingto ambient PM2.5 levels in the San Joaquin Valley Air Basin and the South Coast Air Basin. Attachment 4: lnformation on what measures are included inthe motor vehicle emissions budget calculations, with comparisons of line item adjustmentsto measures used in previous transportation conformity budgets with line item

The energy challenge facing Californiais real. Every Californianneeds to take immediate action to reduce energy consumption. For a list ofsimple ways you can reduce demand and cutyour energy costs, see our website: htt~://w.arb.ca.aov. 

### California Environmental Protection Agency Printed on Recycled Paper

### Elizabeth Adams May 18, 201 1 Page 2 adjustments used in the Transportation Conformity Budgets contained in the 201 1 SIP 

### revision. Attachment 5: Description of irr~provements to California's Motor Vehicle Emissions Inspection and Maintenance (IIM) Program that will improvethe effectiveness of California's IIM program, beginning in January 2013. Ifyou have any questions, please call me at (916) 322-2739, or have your staff contact Mr. Douglas Ito, Chief, Air Quality and Transportation Planning Branch, at (916) 322-0285. Sincerely, 

# ,WT ~ynn Terry Deputy ~xecutive Officer Attachments
cc: (WIO attachments) Mr. Douglas Ito, Ct-lief Air Quality and Transportation Planning Branch Planning and Technical Support Division

### Attachment 1 Emissions Inventory Discussion Appendix E of the ARB staff report describes the inventory improvements ARB made as a part of rulemaking to implement the SIP. The recession does not impact the SIP base year modeling since both regions used a base year prior to the recession. The base year irr~pacts from inventory improvements for the South Coast Air Basin (2002) and the San Joaquin Valley Air Basin (2005) reflected in Tables SC-2002 and SJV-2005, while critical to rulemaking, are small relative to the overall inventory. Small changes in base year emissions would not substantially change the fundamental relationship between emissions and nieasured air quality in the base year modeling. Tables SC-2009, SC-2012, SC-2014, SJV-2009, SJV-2012, and SJV-2014 show the relationships among the detailed information in Appendix C: Reasonable Further Progress Tables, Appendix 

### D: Transportation Conformity Budgets and the detailed methodology included in Appendix E:Additional Documentation.Attachment 1



### Table SC-2002 South Coast Air Basin 2002 

### (AnnualAverage, tpd)

NOx Equivalent SIP Stationary and Areawide 1144 On-road Mobile 1012 Off-road Mobile 1059 Total Inventory 3216
NOx Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory
PM2.5 Current Estimate 

# --- 1144 1095 1069 3292

Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory

sox % Change 0% 8% 1% 2%

SIP 93 628 372 1093

Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory
ROG Current Estimate 93 685 269 1046

SIP 60 18 21 99

Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory Current Estimate 60 19 15 94

SIP 22 4 27 53 Current Estimate 22 5 39 I 65

SIP 303 361 180 844 Current Estimate 303 362 162 827

### Attachment 1



### San Joaquin Valley 

### 2005 

### (AnnualAverage, tpd)

NOx Equivalent Category Stationary and Areawide On-road Mobile I Off-road Mobile Total Inventory
NOx Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory
PM2.5

sox % Change I 0% -9% -12% -4% SIP Current Estimate

SIP 

### 1 Current Estimate

Current Estimate 65

- 10 8 8 2 SIP Category

Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory 96 51 28 176

94

Stationary and Areawide
-- On-road Mobile Off-road Mobile Total Inventory 9 6 47 25 168

94

65 12 9 86

SIP 21 3 2 2 6 Current Estimate 21 2 2 26 328 154 575 315 132 540Attachment 1

Table SC-2009 South Coast Air Basin 2009 (Annual Average, tpd)

NOx

PM2.5 Category 2009 Remaining Emissions 84 397 198 678

1 677 I

Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory

sox Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory

ROG SIP
84 413 326 823

62 18 18 97

2009 Remaining Emissions 22 2 19 43 0 43 Category

Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory Reductionsfrom Adopted Local Measures Estimated Remaining Emissions

62 17 11 89 Reductionsfrom Adopted Local Measures Estimated Remaining Emissions

Stationary and Areawide On-road Mobile Off-road ~obile


### . Total Inventory 0 89 

# -

22 2 21 45



# 1 2009 Reductionsfrom Adopted Local Measures Estimated Remaining Emissions

SIP
241 196 147 584 Reductionsfrom Adopted Local Measures Estimated Remaining Emissions Remaining Emissions 241 192 131 564

0 563Attachment 1

Table SC-2012 South Coast Air Basin 2012 (Annual Average, tpd)

NOx Category Stationaryand Areawide On-road Mobile Off-road Mobile Total Inventory

PM2.5 Category 

# 1
SIP 

# 1 Re2:ing Emissions

sox 

# 1 2012 SIP Remaining

63 16 10 89 1 88 Stationaryand Areawide On-road Mobile Off-road Mobile Total Inventory

Category Stationary and Areawide

-- On-road Mobile Off-road Mobile Total Inventory

ROC 

# 1 2012 76 337 297 710 Reductionsfrom Adopted Local Measures Estimated Remaining Emissions

63 17 17 97 Emissions 76 326 184 586

5 582

Reductions from Adopted Local Measures Estimated Remaining Emissions

SIP
17 2 23 43

Remaining Emissions 247 158 121 525 11 514 Category 2012 Remaining Emissions 17 2 6 26 Reductionsfrom Adopted Local Measures Estimated RemainingEmissions

Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory 0 26

247 I 162 134 542 Reductionsfrom Adopted Local Measures Estimated RemainingEmissionsAttachment 1

Table SC-2014 South Coast Air Basin 2014 (AnnualAverage, 

### tpd)

NOx

PM2.5 2014 Remaining Emissions 75 291 176 542

8 534 Category Stationaryand Areawide On-road Mobile Off-road Mobile Total Inventory

sox SIP
75 292 285 653

2014 Remaining Emissions 64 14 10 88 1 87 Category Stationaryand Areawide On-road Mobile Off-road Mobile Total Inventory

Category Stationary andAreawide On-road Mobile Off-road Mobile Total Inventory

ROG ReductionsfromAdopted Local Measures EstimatedRemaining Emissions

SIP
64 17 16 97 Reductionsfrom Adopted Local Measures Estimated Remaining Emissions

SIP

2014 Remaining Emissions 251 136 116 503 14 489 Category Stationary andAreawide On-road Mobile Off-road Mobile Total Inventory 2014 Remaining Emissions

Reductionsfrom Adopted Local Measures Estimated Remaining Emissions

SIP
251 145 127 524 4 20

Reductionsfrom Adopted Local Measures Estimated Remaining Emissions 17 2 2 5 45 17 2 5 24

### Attachment 1



### San Joaquin 

### Valley 2009 

### (Annual Average, tpd)

NOx

PM2.5



## * The San Joaquin Valley Reasonable Further Progresstables inAppendix Care consistent with the remaining emissions identified inthe New 2009 Baseline Column. SIP Category

sox New 2009 2009 Remaining Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory

2009 Remaining Emissions 61 7 6 75 SIP 

# ~ New 2009 Category

Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory Baseline* 74 208 102 384 74 297 130 501

Stationary and Areawide

- On-road Mobile ---- Off-road Mobile Total Inventory Emissions 74 - 208 102 384 Reductionsfrom Adopted Local Measures Estimated Remaining Emissions

Reductionsfrom Adopted Local Measures Estimated Remaining Emissions Baseline*

2009 Remaining Emissions 2 2

1 SIP 

# 1 New 2009 Baseline*

Reductionsfrom Adopted Local Measures Estimated Remaining Emissions 2

61 11 8
2

2 2

1 381

6 1 7 I 6

73

2 2

1 1 23 0 381

80 I 75
73

23

1 2 3
23 1 23

### Attachment 1



### San Joaquin Valley 201

### 2 (Annual Average, tpd)

NOx

PM2.5



## * The San Joaquin Valley Reasonable Further Progress tables inAppendix C are consistent with the remainingemisiions identified inthe New 2012 Baseline Column. Category Stationary and Areawide On-road Mobile** Off-road Mobile Total Inventory

Category Stationary and Areawide On-road Mobile** Off-road Mobile Total Inventory

sox 

### .



### **The San Joaquin Valley Transportation Conformity Budgets inAppendix D are consistent with the On-road Mobilesource estimated emission values in the 2012 Remaining Emissionscolumn. New2012 Baseline* 70 182 88 340 SIP 70 244 111 424 2012 Remaining Emissions 70 180 88 338 Reductions from Adopted Local Measures Estimated Remaining Emissions

SIP 60 10 7 77

Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory Reductions fromAdopted Local Measures Estimated Remaining Emissions

New2012 Baseline* 22 1 1 24 SIP 2 2 1 1 24 12

New2012 2012 Remaining

2012 Remaining Emissions 2 2 1 1 24 Reductions from Adopted Local Measures Estimated Remaining Emissions 328

Baseline* 60 7 6 74 S 326

Emissions 60 7 6 73
69

3 68

20 20

### Attachment 1



### San Joaquin Valley 

### 2014 

### (Annual Average, tpd)

NOx Category Stationary and Areawide On-road Mobile* Off-road Mobile Total Inventory

PM2.5



### * The San Joaquin Valley Transportation Conformity Budgets in Appendix D are consistent with the Onroad Mobilesource estimated emission values in the 2014 Remaining Emissionscolumn. sox SIP 67 207 102 376

2014 Remaining Emissions 60 5 6 71 Category Stationary and Areawide On-road Mobile* Off-road Mobile Total Inventory Reductionsfrom Adopted Local Measures Estimated Remaining Emissions



# '
SIP New 2014 Baseline 67 161 84 313

ReductionsfromAdopted Local Measures Estimated Remaining Emissions SIP 60 9 7 75

New 2014 Baseline 2 3

1 1 24 Category Stationary and Areawide On-road Mobile Off-road Mobile Total Inventory 2014 Remaining Emissions 67 159 84 311 13

New 2014 Baseline 60 7 6 72

2014 Remaining Emissions 23

1 1 24 23

1 1 24 300

5

ReductionsfromAdopted Local Measures Estimated Remaining Emissions 298

67

4 65

21 21

### Attachment 

### 2
Attainment 

### Year Contingency Estimates 

### For the 2014 attainment year, the additional emission reductions accrued in 201

### 5 are relied upon to meet the contingency requirements for both the San Joaquin Valley and the South Coast. 'The contingency estimates were calculated by taking into account baseline emission reductions that occur between 2014 and 201

### 5 as shown in the 2007 State Strategy emission inventory, as well as emission reductions from recently adopted regulations and recession adjustments. Table 

### I San Joaquin Valley 

### PM2.5 Attainment Year Contingency 

# I Contingency (tpd)

Table 

### 2 'lux 

### PM2.5 sox L I 

### 0 3

South Coast 

### PM2.5 Attainment Year Contingency 

### NOx PM2.5 sox ROG 

### Contingency (tpd) 24 0 0 

### 13

### Attachment 3


### Precursor Effectiveness In order to understandthe relativeeffectiveness of reductions in different precursors contributing to ambient PM2.5, staff of the Air Resources Board (ARB) and the South Coast Air Quality Management District (SCAQMD) conducted air quality modeling sensitivity runs using the modeling conducted for the attainment demonstrations. These relative effectiveness ratios were used to guide control strategy development as well as to normalize the benefits of multiple precursors so they can be reflected interms of a single equivalent precursor. This method also provides a uniform metricfor tracking progress relativeto the attainment emissionstargets. Documentation on the methodologies used for calculatingthe effectiveness ratios in each area is provided below. South Coast A description of the methodology used by SCAQMD staff is provided inAppendix C 

### of ARB'Sstaff report on the SCAQMD 2007 State Implementation Plan which can befound at:

San Joaquin Valley In order to evaluate precursoreffectiveness, ARB staff focused on the response inthe Bakersfield metropolitanarea where the highest PM2.5concentrations in the San Joaquin Valley occur. Staff conducted two grid-based modeling sensitivity runs where the NOx and primary PM2.5 emissionswere reduced, one at a time, by 10% relative to the future-year modeled attainmentscenario. Fromthese sensitivity runs we calculated a 

### future year modeled design value reflectingthe further 10% emission reduction assumptions. The difference between the attainment scenario (before 10% reduction in emissions) and adjusted (after 10% reduction in emissions) design values were then compared. Table 1 shows results for NOx and primary PM2.5 emission reductions as well as the efficacy of reducing primary PM2.5relative to that for NOx. The 

### lS' column of Table 1 lists the Bakersfield area monitoring sites and the 2" column contains the monitored2006 designvalue for those sites. The 3rdcolumn contains the 2014 modeled design values taking into account all of the reductions inthe attainment strategy. The 4Ihand 5'h columns list the adjusted 2014 design values with additional 10% emissions reductionsfor NOx, and primary PM2.5, respectively. The 6'h column lists the effectiveness of controlling primary PM2.5 relative to that of controlling NOx. This analysis showed that controlling primary PM2.5is approximately nine times more effective than controlling NOx based on the average across the three Bakersfieldarea sites.

### Attachment 

### 3 The precursor effectiveness values were calculated by determining the difference between the modeled 2014 attainment design value (3rd 

### column) and the design value of the sensitivity run (4thor 5th 

### col~~mns). This difference was then divided by the tonnage of each precursor corresponding to a 10%domain-wide reduction in emissions to develop the respective precursor effectiveness ratios. 'The 

### PM2.5 effectiveness value was then divided by the NOx 

### effectiveness value to determine a relative ratio (6th column).
Table 1: The effectiveness of precursor controls on the 2014 

### design value.
Site Measured 2006 Design Value (uglm3) Modeled 2014 Design Value With SIP Attainment

Strategy (uglm3) Modeled 2014 Design Value With Additional 10% NOx Reduction

(uglm3) Modeled 2014 Design Value With Additional 10% PM2.5 Reduction

(uglm3) Effectiveness Relative to NOx

Site 1 (Bakersfield-California Site 2 (Bakersfield-Planz) Site 3 (Bakersfield-Golden) 18.5 18.9 18.6 14.3 14.7 14.4 - 14.1 14.6 14.2 13.6 14.0 13.7 8.7 9.3 8.6

### Attachment 

### 4 New Budqets EMFAC2007 Baseline, covering 201

### 2 and 2014 for South Coast and San Joaquin Valley Line ltem Adjustments to Baseline for Measures Adopted Prior to December 2006 (Referredto as "Adjustments to Baseline"in 

### Budgets, adjustments included in 

### applicable years) South Coast and San Joaquin Vallev AB 1493 GHG Standards On-Road Portion of Carl Moyer Program San Joaquin Vallev Onlv District Rule 931 0 

# - School Buses

Adjustments Now Included 

### in New Heavy Duty Diesel Truck Model (Included in "State Strategy Adjustments" in Budgets, adjustments included in applicable years) South Coast and San Joaquin Vallev New HDDT Inventory HDDT Recession Impacts HDDT In-Use Rule HDDT Chip Re-flash HDDT Public Fleet and Solid Waste Rules HDDT Idling Rule

Line ltem Adjustments for Adopted SIP Measures (Included in "State Strategy Adjustments" in Budgets, adjustments included in 

### applicable years) South Coast and San Joaquin Vallev Smog Check Improvements (Low Pressure Evap, Cutpoints, Lt. Duty Diesels, Smoke Test) Reformulated Gasoline South Coast Or~ly AB 923 High Emitter San Joa~uin Vallev Onlv Indirect Source Rule

### Attachment 4 

### Line ltem Adjustments in PM2.5 Conformity Budgets for South Coast and San Joaquin Valley Previous Budgets 

### EMFAC2007 Baseline, covering 2009,2012,2014, 2023 and 2030 for South Coast and 2009,2012 and 2014 for San Joaquin Valley
Line ltem Adjustments To Baseline For Measures Adopted Prior To December2006 

### (Referredto as "Adjustmentsto Baseline" in Budgets, adjustments included in applicable years) South Coast and San Joaquin Valley Heavy Duty Diesel Truck (HDDT) Chip Reflash HDDT Public Fleet and Solid Waste Rules HDDT Idling Rule AB 1493 GHG Standards On-Road Portion of Carl Moyer Program San Joaquin Vallev Onlv District Rule 9310 

## - School Buses

Line ltem Adjustments for ProposedSIP Measures



### (Referredto as "State Strategy Reductions" in Budgets, adjustments included in applicable years) South Coast and San Joaquin Valley All Smog Check Improvements(Low Pressure Evap, Cutpoints, Annual Insp. for Older, Annual Insp. for High Mileage, Motorcycles, Lt. Duty Diesels, Smoke Test) HDDT In-Use Rule Reformulated Gasoline Expanded Vehicle Retirement South Coast Onlv A6 923 High Emitter San Joaquin Vallev Only Indirect Source Rule

### Attachment 5
lmprovements to California's lnspection and Maintenance Program 

### California took a major step forward in improving the effectiveness of the Enhanced Vehicle lnspection and Maintenance (IIM) prog'ramwith the recent passage of Assembly Bill 2289 (Chapter 258, Statutes of 2010). This bill requires that the Bureau of Automotive Repair identify the specific Smog Check stations and individual technicians that are doing the bestjob identifying dirty vehicles and repairing them. The Station and Technician Achievement Rating program, or STAR, will start in January 2013. After that, all vehicles older than model year 1999, can only be inspected by high performingtechnicians at STAR Certified Stations. For all vehicles model year 2000 and newer, California will test the on-board diagnostic computer systems, commonly referred to as OBD-only testing, in place of tailpipe testing. With this, California willjoin the 22 other states that perform OBD-only testing on late model vehicles. This will greatly improve the accuracy and quality of inspections on late model vehicles by taking advantage of the advanced technology, real-time data transfer, and state-of-the-art antifraud provisions built into OBD II equipped vehicles. Other improvementsto California's I/M programwill include revisions to the enforcement fine structure to improve industry compliance, mandated annual reporting, and support for technician training programs through community colleges and private training entities. Comparison of lmprovements to California's Enhanced IIM Proaram 

### Existing IIM Program Gold Shield Test and Repair Test and Repair
Vehicles OnlyIGold Shield stations. lmprovements STAR certified stations (test-only and test and repair) Non-STAR certified stations (testonly and test and repair) All model year 1999 and older vehicles directedto STAR stations. Model year 2000 and newer receive OBD-onlv ins~ections. Program Performance

inspections. I 

### USEPA approvedthe enhanced STAR performance criteria are program in 2009 as a CaliforniaSIP more stringent than Gold Shield. revision based on modelingthat showed the enhanced program The USEPA 

### acknowledgesthe effectivenessof OBD II inspections meets or exceeds the federal by providingfull emission credits to performance standard. IIM programs with OBD-Only