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Table of Contents 

Connecticut PM2.5 Redesignation Request and Maintenance Plan 

Executive Summary 

CHAPTER 1 INTRODUCTION AND BACKGROUND 1

1.1 Particulate Matter Formation and Health Effects 1

1.2 Particulate Matter NAAQS History 2

1.2.1 1997 PM2.5 NAAQS 2

1.2.2 2006 PM2.5 NAAQS 5

1.3 Required Elements for PM2.5 Redesignation 5

CHAPTER 2 DEMONSTRATION OF ATTAINMENT OF THE PM2.5 STANDARDS 7

2.1    Monitoring Network 7

2.2 Data Handling and Quality Assurance 7

2.3 PM2.5 Monitoring Data Analysis 10

CHAPTER 3 APPLICABLE REQUIREMENTS UNDER CAA SECTION 110 AND TITLE 1 PART D 21

3.1 Satisfying Section 110 General SIP Requirements 21

3.2 Satisfying Part D Requirements 22

3.3 Fully Approved SIP Under Section 110(k) 24

CHAPTER 4 PERMANENT AND ENFORCEABLE EMISSION REDUCTIONS 25

4.1 Federal Control Measures 25

4.1.1 Tier 2 Vehicle Standards and Gasoline Sulfur Standards 25

4.1.2 Heavy-Duty Diesel and Gasoline Highway Vehicle Standards 27

4.1.3 Motorcycle Exhaust Standards 27

4.1.4 Large Non-road Diesel Engine Standards 27

4.1.5 Non-road Spark-Ignition Engines and Recreational Engine Standards 28

4.1.6 NOx SIP Call, CAIR and CSAPR Programs 28

4.2 Connecticut Control Measures 29

4.2.1 Control of SO2 and NOx Emissions from Power Plants and Other Large Stationary Sources 31

4.2.2 The Post-2002 Nitrogen Oxides (NOx) Budget Program 31

4.2.3 CAIR and Connecticut’s CAIR Replacement Rule 31

4.2.4 Outdoor Wood Burning Furnace (OWBF) Restrictions 32

4.2.5 Improvements in the Control of Particulate Matter and Visible Emissions 32

4.2.6 Connecticut Enhanced I/M (ASM 2525 final standards) and OBD-II Enhanced I/M 33

4.2.7 California Low Emission Vehicle 2 (CALEV2) 33

4.2.8 Reducing NOx Emissions from Municipal Waste Combustors 33

4.2.9 Conclusions 34
iv 

CHAPTER 5 MAINTENANCE PLAN 35

5.1 Attainment Inventory and Demonstration of Continued Maintenance 35

5.1.1 Pollutants 37

5.1.2 Source Categories 37

5.1.3 Geographic and Temporal Resolution 37

5.1.4 Point Source Inventory Procedures 38

5.1.5 Area Source Inventory Procedures 41

5.1.6 Non-Road Source Inventory Procedures 44

5.1.6.1 NMIM/NONROAD Modeling Methodology 44

5.1.6.2 MAR Methodology 45

5.1.7 On-Road Mobile Source Inventory Procedures 48

5.1.8 Comparison of Attainment Year and Projected Future Year Emissions 56

5.1.9 Motor Vehicle Emission Budgets 59

5.2 Ambient Monitoring Network Commitment 61

5.3 Verification of Continued Attainment 61

5.4 Contingency Plan 62

5.4.1 Warning Level Response 62

5.4.2 Action Level Response 63

5.5 Commitment to Revise Plan 63

CHAPTER 6 SUMMARY AND CONCLUSIONS 644

6.1 Area Has Attained the NAAQS 644

6.2 Applicable CAA Section 110 and Title 1 Part D Requirements are Satisfied 644

6.3 Attainment is Due to Permanent and Enforceable Emission Reductions 655

6.4 Maintenance Plan Ensures Continued Attainment 66

6.5 Withdrawal of the Attainment Demonstration 66
v 

List of Tables

Table 2.1 Connecticut PM2.5 Monitors: Data Completeness by Quarter 2008 – 2010 (Percent) ....................... 9

Table 2.2 Annual PM2.5 Design Values1 in Connecticut’s Portion of the NY-NJ-CT Nonattainment Area2

(μg/m3

) ............................................................................................................................................ 13

Table 2.3 24-hour PM2.5 Design Values1 in Connecticut’s Portion of the NY-NJ-CT Nonattainment Area2

(μg/m3

) ............................................................................................................................................ 13

Table 4.1 Post-2002 Control Measures ........................................................................................................... 26

Table 4.2 Comparison of Actual EGU Emissions from States Impacting Connecticut’s PM2.5 Air Quality .. 30

Table 5.1 CT DEEP Banked Emission Reduction Credits .............................................................................. 39

Table 5.2 MOVES Run Specifications ........................................................................................................... 50

Table 5.3 MOVES County Data Manager (CDM) .......................................................................................... 52

Table 5.4 References Cited in Table 5.2 and 5.3 ............................................................................................ 55

Table 5.5 Comparison of MOVES Emissions for 2007 and 2009 .................................................................. 56

Table 5.6 Connecticut PM2.5 Emissions Inventory Projections 2007-2025 .................................................... 57

Table 5.7 Connecticut NOx Emissions Inventory Projections 2007- 2025 ..................................................... 57

Table 5.8 Connecticut SO2 Emissions Inventory Projections 2007-2025 ....................................................... 58

Table 5.9 New York Preliminary Emissions Projections 2007-2025 .............................................................. 59

Table 5.10 New Jersey Preliminary Emission Projections 2007-2025 ............................................................. 59

Table 5.11 Transportation Conformity Budgets for Connecticut’s Portion of the NY-NJ-CT Area ................ 61

 
vi 

List of Figures

Figure 1.1 The NY-NJ-CT Annual and 24-hour PM2.5 Nonattainment Areas .................................................... 4

Figure 2.1 Connecticut’s PM2.5 Monitoring Network ....................................................................................... 8

Figure 2.2 2010 Annual Design Values............................................................................................................ 11

Figure 2.3 2010 24-hour Design Values ........................................................................................................... 12

Figure 2.4 Annual Design Value Trends for Monitors in Connecticut’s Portion of the NY-NJ-CT Area ....... 15

Figure 2.5 Annual Design Value Trends for Monitors in New York’s Portion of the NY-NJ-CT Area .......... 16

Figure 2.6 Annual Design Value Trends for Monitors in New Jersey’s portion of the NY-NJ-CT Area ........ 17

Figure 2.7 24-hour Design Value Trends for Monitors in Connecticut’s portion of the NY-NJ-CT Area ....... 18

Figure 2.8 24-hour Design Value Trends for Monitors in New York’s portion of the NY-NJ-CT Area ......... 19

Figure 2.9 24-hour Design Value Trends for Monitors in New Jersey’s portion of the NY-NJ-CT Area ....... 20
vii 

Appendices

Appendix A Version 3.3 Technical Support Document for the Development of the 2007 Emission INventory 

for Regional Air Quality Modeling in the Northeast/Mid-Atlantic Region; Prepared for 

MARAMA by AMEC Environment & Infrastructure and SRA International, Inc.; January 23, 

2012.

Appendix B Version 3.3 Technical Support Document for the Development of the 2025 Emission Inventory 

for PM Nonattainment Counties in the MANE-VU Region; Prepared for MARAMA by AMEC 

Environment & Infrastructure and SRA International, Inc.; January 23, 2012

Appendix C Version 3.3 Technical Support Document for the Development of the 2017 / 2020 Emission 

Inventories for Regional Air Quality Modeling in the NOrtheast / Mid-Atlantic Region; January 

23, 2012

Appendix D File Locations for Additional Documentation on Inventory Development Process

Appendix E Connecticut Department of energy and Environmental Protection's Review of the Seasonality of 

High PM2.5 Days.

Appendix F Excerpts from Connecticut's 2005 Draft Periodic Emission Inventory (PEI) for Ozone and Carbon 

Monoxide

Appendix G Connecticut 2007 Airport Related Emissions Provided to MARAMA for Inclusion in the 2007 

MANE-VU Inventory 

Appendix H Connecticut 2007 Locomotive Emissions Provided to MARAMA for Inclusion in the 2007 

MANE-VU Inventory 

Appendix I Connecticut MOVES On-Road Modeling Documentation 
E-1 

Executive Summary

This document presents the Connecticut Department of Energy and Environmental Protection’s (CT 

DEEP) request to redesignate Connecticut’s portion of the New York-New Jersey-Connecticut (NY-NJCT) nonattainment area to attainment for the federal 1997 annual and 2006 24-hour National Ambient Air 

Quality Standards (NAAQS) for fine particulate matter less than a nominal 2.5 micrometers in diameter 

(PM2.5). Evidence is provided satisfying Clean Air Act (CAA) sections 107(d)(3)(E) and 175A, which 

specify the requirements that must be met for the U.S. Environmental Protection Agency (EPA) to 

redesignate a nonattainment area to attainment status. These requirements include demonstrations that: 

• The area has attained the NAAQS; 

• The applicable implementation plan is fully approved under CAA section 110(k) and the area has 

met all applicable requirements of CAA section 110 and part D; 

• The air quality improvements are due to permanent and enforceable emission reductions; 

• The area has a fully approved a maintenance plan satisfying CAA section 175A. 

E.1 Background

Fine particles in the atmosphere are comprised of a complex mixture of components, including sulfate 

(SO4), nitrate (NO3), ammonium, elemental carbon, organic compounds and inorganic material (e.g., 

metals, dust, sea salt) generally referred to as ‘crustal material.’ Primary particles are emitted directly 

into the air as solid or liquid particles (e.g., elemental carbon from diesel engines). Secondary particles 

form in the atmosphere over time because of various chemical reactions (e.g., gaseous sulfur dioxide and 

ammonia reacting to form ammonium sulfate particles). Consequently, PM2.5 experienced at one location 

can have origins both nearby and distant. 

The annual average and 24-hour average PM2.5 NAAQS were initially established by EPA in 1997 and 

revised in 2006, based on evidence demonstrating that serious health effects are associated with exposure 

to elevated levels of PM2.5, mainly because particles of this size can easily reach into the deepest regions 

of the lungs. Significant health effects associated with PM2.5 exposure include premature mortality, 

aggravation of respiratory and cardiovascular disease, decreased lung function and difficulty breathing, 

asthma attacks, as well as cardiovascular problems such as heart attacks and cardiac arrhythmia. 

Particularly sensitive individuals include older adults, people with heart and lung disease, and children. 

Connecticut’s Fairfield and New Haven Counties are currently designated by EPA as nonattainment for 

both the 1997 annual and 2006 24-hour PM2.5 NAAQS and are grouped with several counties in New 

York and northern New Jersey in a multi-state (NY-NJ-CT) nonattainment area that encompasses 

metropolitan New York City, as shown in Figure E-1. EPA established these nonattainment areas in 2005 

for the annual NAAQS and in 2009 for the 24-hour NAAQS based on PM2.5air quality measured prior to 

those years. 
E-2 

Figure E-1. New York-New Jersey-Connecticut (NY-NJ-CT) Annual/24-hour PM2.5 Nonattainment Area 
E-3 

E.2 Monitoring Shows Compliance with PM2.5 NAAQS 

As shown in Figures E-2 and E-3, PM2.5 air quality has improved significantly over the last decade in the 

Connecticut portion of the NY-NJ-CT area. Similar improvements have occurred in the New York and 

New Jersey portions of the area as well. Connecticut’s portion of the nonattainment area measures 

compliance with the 15 μg/m3

 annual NAAQS, with a maximum 2010 design value of 10.3 μg/m3. As a 

whole, the area first reached compliance with the annual NAAQS in 2008, with a most recent (2010) 

maximum design value of 12.5 μg/m3

, measured in New York City. 

Connecticut’s portion of the area first measured compliance with the 35 μg/m3

 24-hour NAAQS in 2008, 

with a maximum 2010 design value of 29 μg/m3. As a whole, the NY-NJ-CT area first complied with the 

24-hour NAAQS in 2009 and has a most recent (2010) maximum design value of 30 μg/m3

, measured in 

New Jersey. Therefore, the entire NY-NJ-CT area has complied with both NAAQS since 2009. 

E.3 Applicable CAA Section 110 and Title 1 Part D Requirements are Satisfied 

Connecticut has submitted “infrastructure SIPs” addressing CAA section 110(a) requirements, for both 

the 1997 annual and 2006 24-hour PM2.5 NAAQS. EPA has found Connecticut’s infrastructure SIP 

submittal for the 1997 annual NAAQS to be complete, but has not yet issued rulemakings to approve the 

infrastructure SIPs for either of the NAAQS. Nonetheless, previous redesignation rulemakings issued by 

EPA for other areas conclude that section 110 elements that are not connected with nonattainment plan 

submissions and are not linked with an area’s attainment status are not applicable requirements for 

purposes of redesignation, because a state remains subject to these requirements after redesignation. 

CAA Subpart 1 of part D sets forth the basic nonattainment requirements applicable to all nonattainment 

areas. All areas that were designated nonattainment for the 1997 annual or the 2006 24-hour PM2.5 

NAAQS were designated under this subpart of the CAA, and the requirements applicable to them are 

contained in sections 172 and 176. For purposes of evaluating redesignation requests, the applicable part 

D, subpart 1 SIP requirements are contained in sections 172(c)(1)–(9) and in section 176. 

States with nonattainment areas are required to submit a plan to reach attainment. Connecticut submitted 

an attainment demonstration for its portion of the annual nonattainment area in November 2008, meeting 

CAA sections 172 and 176 requirements. See Section E.6 for further discussion regarding that attainment 

demonstration. Attainment demonstrations for the 24-hour NAAQS are due in December 2012. 

As discussed earlier, all monitors in the NY-NJ-CT area show compliance with both the annual and 24-

hour NAAQS. EPA has already recognized that the multi-state area has “clean data” in accordance with 

40 CFR 51.1004(c), for the annual NAAQS. Connecticut has requested a similar “clean data” finding for 

the 24-hour NAAQS and is awaiting EPA action. The requirement to submit the 24-hour NAAQS 

attainment demonstration would no longer apply if EPA issues a “clean data” finding for that NAAQS, or 

if EPA approves this redesignation request for the 24-hour NAAQS before the December 2012 due date. 

CAA section 172(c)(3) requires an inventory of actual emissions. The maintenance plan portion of this 

submittal includes a 2007 base year emissions inventory that meets the requirement. 
E-4 

Figure E-2 Annual Design Value Trends in Connecticut’s Portion of the NY-NJ-CT Area

Figure E-3 24-Hour Design Value Trends in Connecticut’s Portion of the NY-NJ-CT Area

0

2

4

6

8

10

12

14

16

18

2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

μg/m3

Connecticut Annual PM2.5 Design Values 2001‐2010

Bridgeport (09‐001‐0010) Danbury (09‐001‐1123)

Stamford HS (09‐001‐2124) Norwalk (09‐001‐3005)

Westport (09‐001‐9003) New Haven Fire House (09‐009‐0026)

New Haven Criscuolo (09‐009‐0027) New Haven State St (09‐009‐1123)

New Haven Ag Station (09‐009‐2008) Waterbury (09‐009‐2123)

Hamden Millrock (09‐009‐9005)

Annual NAAQS

0

5

10

15

20

25

30

35

40

45

2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

μg/m3

Connecticut 24‐hr PM2.5 Design Values 2001‐2010

Bridgeport (09‐001‐0010) Danbury (09‐001‐1123)

Stamford HS (09‐001‐2124) Norwalk (09‐001‐3005)

Westport (09‐001‐9003) New Haven Fire House (09‐009‐0026)

New Haven Criscuolo (09‐009‐0027) New Haven State St (09‐009‐1123)

New Haven Ag Station (09‐009‐2008) Waterbury (09‐009‐2123)

Hamden Millrock (09‐009‐9005)

24‐hr NAAQS
E-5 

EPA’s PM2.5 implementation rules require states to adopt specified new source review (NSR) permitting 

revisions by July 20, 2012. CT DEEP held a public hearing in November 2011 to consider revisions to 

Sections 22a-174-1 and 22a-174-3a of the Regulations of Connecticut State Agencies (RCSA) to include 

significant impact levels, significant emissions rates and increments for PM2.5, consistent with EPA’s 

requirements. CT DEEP anticipates that the revised regulations will be submitted as a SIP revision by the end 

of summer 2012, at which point Connecticut will have in place all applicable CAA Section 110 and Title 1 

Part D requirements necessary for PM2.5 redesignation. 

E.4 Attainment Results from Permanent and Enforceable Emission Reductions 

Numerous federal and state emission control programs have been adopted and implemented over the last 

decade, providing permanent and enforceable reductions in direct PM2.5 and PM2.5 precursor emissions (e.g., 

SO2 and NOx) in Connecticut and some upwind areas. Table E-1 lists post-2002 NOx, SO2 and PM2.5 control 

measures that are largely responsible for the significant improvements realized in measured PM2.5 air quality. 

Some of these control programs (e.g., on-road vehicle and non-road engine standards) will provide additional 

emission reductions during the maintenance period, ensuring continued compliance with the NAAQS. 

Connecticut requests withdrawal of one control measure cited in the attainment demonstration for the 1997 

annual PM2.5 NAAQS (submitted November 18, 2008). No applications were ever received for a general 

permit issued for distributed generation sources (authorized under CGS 22a-174(k) and section 102 of Public 

Act 07-242). The general permit has since expired, with no plans for renewal. Therefore, there is no need to 

include the general permit in the SIP. 

E.5 Maintenance Plan Provides for Continuing Attainment 

CAA section 175A establishes the required elements of a maintenance plan for areas seeking redesignation 

from nonattainment to attainment. Plans must include: an inventory sufficient to ensure attainment; a 

demonstration that the plan provides for continued NAAQS compliance through the first 10-year maintenance 

period; a commitment to maintain an appropriate monitoring network; methods to track the progress of the 

maintenance plan and contingency measures to be implemented if NAAQS violations occur during the 

maintenance period. 

Attainment and Future Year Inventories Demonstrate Continued NAAQS Compliance

Comprehensive inventories were developed in collaboration with other states in the Mid-Atlantic/ Northeast 

Visibility Union (MANE-VU) to support future multi-pollutant planning efforts. That regional effort also 

served as the basis for developing inventories needed by states, such as Connecticut, seeking PM2.5

redesignation. Figures E-4, E-5 and E-6 compare PM2.5, NOx and SO2 emission estimates, respectively, for 

Connecticut’s portion of the NY-NJ-CT area for the representative attainment year1

 (2007), an interim year 

(2017) and the end of the maintenance period (2025). Projected emission trends are also displayed for the 

nonattainment area as a whole. Note that emission estimates for the New York and New Jersey portions of the 

area are based on preliminary MARAMA inventory estimates (version 3_3) and are subject to change by each 

state in their PM2.5 redesignation SIP submittals. 

_________________________ 

1 See Section 5.1.7 of this TSD for an explanation of why CT DEEP elected to use 2009 MOVES on-road estimates 

in the 2007 attainment year inventory.
E-6 

Table E-1 Adopted Post-2002 Federal and Connecticut Control Measures 

Control Measure PM NOX SO2

Federal Programs

Tier 2 Vehicle Standards and Gasoline Sulfur Standards X X X 

Heavy-Duty Diesel and Gasoline Highway Vehicle Standards X X X 

Motorcycle Exhaust Standards X 

Large Non-road Diesel Engine Standards X X X 

Non-road Spark-Ignition Engines and Recreational Engine 

Standards X X X 

NOx SIP Call X 

CAIR X X 

State Programs

Control of Sulfur Dioxide and Nitrogen Oxide Emissions from 

Power Plants and Other Large Stationary Sources 

RCSA Sections 22a-174-19a and 22a-174-22(e)(3) 

X X 

The Post-2002 Nitrogen Oxides (NOx) Budget Program 

RCSA Section 22a-174-22b X 

CAIR NOX Ozone Season Trading Program 

RCSA Section 22a-174-22c X 

Outdoor Wood Burning Furnace Restrictions 

Section 22a-174k of the Connecticut General Statutes X 

Improvements in the Control of Particulate Matter and Visible 

Emissions RCSA Section 22a-174-18 X X 

Connecticut Enhanced Inspection and Maintenance Program 

(ASM 2525 final standards and OBD II program) 

RCSA Section 22a-174-27 

 X 

CT’s California Low Emission Vehicle Phase 2 (CALEV2) 

RCSA Section 22a-174-36b X X 

Reductions in NOx emissions from Municipal Waste Combustors 

(Phase 2) RCSA Section 22a-174-38 X 

NSR Permit to Construct and Operate Stationary Sources 

RCSA Section 22a-174-3a X X X 
E-7 

Figure E-4 Projected PM2.5 Emissions for the CT Portion and All of the NY-NJ-CT Area* 

* Emission estimates for NY and NJ are preliminary and are subject to change by each state in their PM2.5 redesignation SIP submittals.

Figure E-5 Projected NOx Emissions for the CT Portion and All of the NY-NJ-CT Area* 

* Emission estimates for NY and NJ are preliminary and are subject to change by each state in their PM2.5 redesignation SIP submittals.

0

10,000

20,000

30,000

40,000

50,000

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

2007 2017 2025

NY‐NJ‐CT

TPY

CT

TPY

PM2.5 Emission Trends for the

CT Portion and All of the NY‐NJ‐CT Area

CT Point

NonEGU

CT Point EGU

CT Onroad

MOVES

CT Nonroad

NMIM

CT Nonroad

MAR

CT Area

NY‐NJ‐CT

TOTALS

0

100,000

200,000

300,000

400,000

500,000

0

10,000

20,000

30,000

40,000

50,000

60,000

2007 2017 2025

NY‐NJ‐CT

TPY

CT

TPY

NOx Emission Trends for the

CT Portion and All of the NY‐NJ‐CT Area CT Point

NonEGU

CT Point EGU

CT Onroad

MOVES

CT Nonroad

NMIM

CT Nonroad

MAR

CT Area

NY‐NJ‐CT

TOTALS
E-8 

Figure E-6 Projected SO2 Emissions for the CT Portion and All of the NY-NJ-CT Area* 

* Emission estimates for NY and NJ are preliminary and are subject to change by each state in their PM2.5 redesignation SIP submittals.

Results demonstrate that total emissions of all three PM2.5-related pollutants decrease significantly 

through the maintenance period in both the Connecticut portion and throughout the entire NY-NJ-CT 

area. PM2.5 emissions are projected to decrease by 22%, NOx by 52% and SO2 by 43% between 2007 and 

2025 in the Connecticut portion of the area, with similar reductions expected for the entire area. These 

projected reductions occur due to the currently adopted federal and state control programs listed in Table 

E-1, with no additional control strategies necessary to maintain the NAAQS through 2025. Therefore, the 

Section 175A mandate to demonstrate continued compliance during the maintenance period is satisfied.

Motor Vehicle Emission Budgets 

The maintenance plan establishes PM2.5 and NOx transportation conformity budgets1 for 2017 and 2025 to 

ensure that future emissions from on-road mobile sources provide for continuing attainment of the PM2.5 

NAAQS. As depicted in Figure E-6, on-road emissions of SO2 are de minimis, comprising less than 2% 

of total SO2 emissions from all source categories; therefore, conformity budgets are not established for 

SO2. Conformity budgets for direct PM2.5 emissions do not include either re-entrained road dust or 

construction dust from transportation projects; however, emission estimates for both of those categories 

are included in the area source portion of the inventory. 

______________________________ 

1 EPA previously approved 2009 PM2.5 and NOx conformity budgets for CT’s portion of the nonattainment area that 

were established using EPA’s emissions model, MOBILE6.2. Emissions budgets in the maintenance plan are based 

on EPA’s recently released MOVES model, which supplanted the MOBILE6.2 model as EPA’s required method of 

determining on-road emissions. CT DEEP is requesting withdrawal of the 2009 MOBILE6.2 budgets and approval 

of 2017 and 2025 MOVES budgets. See Section 5.1.9 of this TSD for an explanation of why 2009 budgets are no 

longer necessary and Section 5.1.7 of this TSD for an explanation of why CT DEEP elected to use 2009 MOVES 

on-road estimates in the 2007 attainment year inventory.

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

2007 2017 2025

NY‐NJ‐CT

TPY

CT

TPY

SO2 Emission Trends for the

CT Portion and All of the NY‐NJ‐CT Area CT Point

NonEGU

CT Point EGU

CT Onroad

MOVES

CT Nonroad

NMIM

CT Nonroad

MAR

CT Area

NY‐NJ‐CT

TOTALS
E-9 

Since total combined emissions from all source sectors are projected to decline significantly during the 

maintenance period (see Figures E-4 and E-5), both the 2017 and 2025 projected emission levels provide 

a “safety margin” relative to total emissions in the 2007 attainment year. CT DEEP is allocating a small 

portion (i.e., 10%) of that safety margin to the 2017 and 2025 conformity budgets, as shown in Table E-2. 

Table E-2 Transportation Conformity Budgets for the Connecticut Portion of the NY-NJ-CT Area 

Year 

PM2.5

(tons/year) 

NOx

(tons/year) 

2017 On-Road Inventory 467.4 10,708.0 

 Safety Margin vs. 2007 1083.9 20,837.8 

 10% of Safety Margin 108.4 2,083.8 

2017 Conformity Budget 575.8 12,791.8 

2025 On-Road Inventory 378.9 7,113.4 

 Safety Margin vs. 2007 1371.3 26,146.9 

 10% of Safety Margin 137.1 2,614.7 

2025 Conformity Budget 516.0 9,728.1 

Monitoring Commitment and Tracking Progress of the Maintenance Plan 

CT DEEP commits to maintaining an appropriate PM2.5 monitoring network through the maintenance 

period, with any potential changes to be developed in collaboration with EPA and subject to stakeholder 

review that occurs with annual monitoring network plans and five-year network assessment reports. CT 

DEEP will continue to conduct ambient PM2.5 monitoring in accordance with 40 CFR 58 requirements 

and expeditiously review data as it becomes available to evaluate any risk of impending NAAQS 

violations. CT DEEP will also regularly review available emission inventory updates produced by EPA 

and CT DEEP. Both of these indicators will be used as potential triggers for early action in the 

contingency plan described below. 

Contingency Plan 

CT DEEP will implement a two-level plan to identify, examine and, if necessary, implement appropriate 

action for monitored PM2.5 levels that approach or violate the 1997 annual or 2006 24-hour PM2.5

NAAQS. An initial Warning Level Response will be triggered based on PM2.5 levels that approach the 

NAAQS. This voluntary commitment is intended to evaluate the need for early actions to prevent 

violations of the NAAQS from ever occurring during the maintenance period. The Warning Level 

Response will be triggered based on annual reviews of measured PM2.5 levels. If either a single year’s 

98th percentile daily value or a single year’s annual average exceeds the NAAQS (note that violations are 

based on three year averages), CT DEEP will examine available information (e.g., meteorology, 

exceptional events, local changes in source activity, source malfunctions/noncompliance or unexpected 

emissions increases) to identify contributing factors and make a judgment on whether any early corrective 

actions are warranted. 
E-10 

Should early actions not be successful and a subsequent verified violation occurs, an Action Level 

Response will be triggered. CT DEEP will first conduct the same types of investigations described above 

to determine potential causes and available resolutions. If the causes are within the jurisdiction and 

control of CT DEEP (e.g., not predominantly due to interstate transport or exceptional events), one or 

more control measures such as those in the example list below will be pursued for implementation. 

Ultimately, contingency measures will be selected from a comprehensive list of measures deemed 

appropriate and effective at the time the selection is made. The selection of measures will be based upon 

the presumed cause of the violation, cost effectiveness, emission reduction potential, economic and social 

considerations, or other appropriate factors. Stakeholder input will be solicited from interested and 

affected persons in the maintenance area prior to selecting any appropriate contingency measures. 

Because it is not possible at this time to determine what control measure will be appropriate at any future 

time during the maintenance period, the list of possible measures below is not intended to be exclusive or 

exhaustive. 

• Control measures already adopted, but designed to produce additional reductions after the 

verified violation occurred (e.g., mobile source measures that involve fleet turnover); 

• New control measures that may be adopted for other purposes (e.g., Tier 3 or CALEV3); 

• Corrections to source noncompliance or malfunctions; 

• Alternative fuel and/or diesel retrofit programs for fleet vehicle operations; 

• New or more stringent PM2.5, NOx or SO2 controls on stationary sources; 

• Wood stove change out program; 

• “No burn” days during cold weather inversion events; 

• Enhanced idle restrictions; 

• Transportation control measures selected in consultation with the Connecticut Department of 

Transportation (CTDOT) and affected local metropolitan planning organizations (e.g., traffic 

flow improvements, transit improvements, trip reduction programs, other new or innovative 

transportation measures). 

CT DEEP commits to pursue adoption of any appropriate measures with a goal of achieving 

implementation within 18 months from the date when the violation triggering the Action Level Response 

is verified. As required by CAA 175A(d), upon verification of a NAAQS violation, CT DEEP also 

commits to implement all measures that were contained in the SIP before the area was redesignated to 

attainment. 

Commitment to Revise Plan 

CT DEEP commits to submit a revised maintenance plan eight years after EPA finalizes redesignation. 

The revision will demonstrate that attainment will continue to be maintained for the 10 years following 

the initial 10-year period, as required by CAA section 175A(b). 
E-11 

E.6 Withdrawal of the Attainment Demonstration

Connecticut submitted an attainment demonstration for Connecticut’s portion of the NY-NJ-CT annual 

PM2.5 nonattainment area in November 2008. EPA subsequently issued a Clean Data Determination 

(CDD) on November 15, 2010 (75 FR 69589), ruling that the NY-NJ-CT area attained the 1997 annual 

PM2.5 standard based on 2007-2009 monitoring data. Among other things, the CDD suspended the 

requirement for Connecticut to submit an attainment demonstration for the 1997 PM2.5 NAAQS. Per 40 

CFR 51.1004(c), suspension of that requirement remains in place until the area is redesignated to 

attainment or EPA determines that the area has recorded new violations of the NAAQS. 

Citing the November 2010 CDD ruling, EPA has suggested that Connecticut withdraw its November 

2008 attainment demonstration SIP revision, except for adopted control measures. Based on the 

requirements of 40 CFR 51.1004(c), however, the Department believes withdrawing the attainment 

demonstration prior to the date on which EPA approves the redesignation/maintenance plan would be 

premature since violations measured prior to that date could result in reinstatement of the legal obligation 

to submit an attainment demonstration. 

In light of this concern, the Department hereby withdraws the attainment demonstration SIP, effective one 

day after EPA signs the final rule approving Connecticut’s redesignation request and maintenance plans. 

This timing ensures that either the attainment plan or the maintenance plan will be in place at all times for 

Connecticut’s portion of the area. The Department also specifies this withdrawal does not apply to any 

control measure except for the general permit described in Section E.4 of the Executive Summary. All 

other control measures remain in the SIP to ensure continued maintenance of the NAAQS.
1 

Chapter 1 Introduction and Background 

This technical support document (TSD) presents the Connecticut Department of Energy and 

Environmental Protection’s (CT DEEP) request to redesignate Connecticut’s portion of the New YorkNew Jersey-Connecticut (NY-NJ-CT) area to attainment for the federal 1997 annual and 2006 24-hour 

National Ambient Air Quality Standard (NAAQS) for fine particulate matter less than a nominal 2.5 

micrometers in diameter (PM2.5). The plan demonstrates that Connecticut’s air quality meets both 

standards due to a combination of national, regional and local control measures implemented to reduce 

emissions and presents a maintenance plan that will ensure continued attainment through the year 2025. 

1.1 Particulate Matter Formation and Health Effects 

Fine particles in the atmosphere are comprised of a complex mixture of components. Common 

constituents include: sulfate (SO4); nitrate (NO3); ammonium; elemental carbon; a great variety of organic 

compounds; and inorganic material, including metals, dust, sea salt, and other trace elements (generally 

referred to as ‘crustal material’). Primary particles are emitted directly into the air as a solid or liquid 

particle (e.g., elemental carbon from diesel engines or fire activities, or condensable organic particles 

from gasoline engines). Secondary particles form in the atmosphere over time because of various 

chemical reactions (e.g., gaseous sulfur dioxide and ammonia reacting to form ammonium sulfate 

particles). Consequently, PM2.5 experienced at one location can have origins both nearby and distant. 

The annual average and 24-hour average PM2.5 NAAQS were initially established by the United States 

Environmental Protection Agency (EPA) in 1997 and revised in 2006, based on evidence from numerous 

health studies demonstrating that serious health effects are associated with exposure to elevated levels of 

PM2.5. Epidemiological studies have shown statistically significant correlations between elevated PM2.5

levels and premature mortality. Individuals particularly sensitive to PM2.5 exposure include older adults, 

people with heart and lung disease, and children.1

The health effects associated with exposure to fine particles are significant, mainly because very small 

particles of this size can easily reach into the deepest regions of the lungs. Significant health effects 

associated with fine particle exposure include: 

• premature mortality; 

• aggravation of respiratory and cardiovascular disease (as evidenced by increased hospital 

admissions, emergency room visits, school/work absences, and restricted activity days); 

• decreased lung function and difficulty breathing; 

• asthma attacks; and 

• certain cardiovascular problems such as heart attacks and cardiac arrhythmia.2,3,4 

                                                           

1

 62 FR 38652-690 (July 18, 1997). 

2

 72 FR 20586, April 25, 2007. 

3

 “Air Quality Criteria for Particulate Matter”, United States Environmental Protection Agency, Research Triangle 

Park, North Carolina: National Center for Environmental Assessment—RTP, Office of Research and Development; 

EPA/600/P–99/002aF and EPA/600/P–99/002bF. October 2004. 
2 

The EPA has estimated that attainment of the annual and daily PM2.5 standards nationally would prolong 

tens of thousands of lives and prevent tens of thousands of hospital admissions each year.5

 In addition, 

these standards would prevent hundreds of thousands of doctor visits, absences from work and school, 

and respiratory illnesses in children. The elderly have been shown to be particularly at risk for premature 

death from the effects of particulate matter. Health studies indicate that there is no clear threshold below 

which adverse effects are not experienced by at least certain segments of the population. 

 

Although fine particulate matter generated from all sources can cause serious health impacts, particulate 

matter generated from diesel combustion is particularly troublesome. The concern over diesel particulate 

matter is two-fold. First, while diesel engines collectively are large sources of NOx and direct fine 

particle emissions, they also emit significant amounts of toxic air pollutants.6 Second, the size of diesel 

particulate matter may add to its health impacts. Almost all of the particles produced by diesel exhaust 

are fine particulate matter (below 2.5 micrometers in diameter), much in the ultra-fine range (that is, 

particles with an aerodynamic diameter of less than 0.1 micrometer). Since both fine and ultra-fine 

particles are respirable, many of these particles are not captured by the human respiratory system’s 

defense mechanisms and enter deep into the lungs. Studies have shown that ultra-fine particles are so 

small that they are capable of penetrating all the way to the cellular level, where they may induce 

structural damage in the body’s core building blocks. 

1.2 Particulate Matter NAAQS History 

The 1970 Clean Air Act (CAA) amendments established health and welfare protective limits, or national 

ambient air quality standards (NAAQS), for a number of air pollutants, including particulate matter. EPA 

first issued standards for total suspended particulate matter in 1971 and revised the standards to target 

PM10 (i.e., particles less than a nominal 2.5 micrometers in diameter) in 1987 and PM2.5 1997. In 

September 2006, the Agency revised the 1997 PM2.5 standards. 

1.2.1 1997 PM2.5 NAAQS 

On July 18, 1997, the EPA established two primary NAAQS for fine particles:

• An annual PM2.5 health-based standard of 15 micrograms per cubic meter (μg/m3

) (annual 

arithmetic mean not to be exceeded over a three year average); and 

• A daily (24-hour) PM2.5 health-based standard of 65 μg/m3

 (the three year average of 98th

percentile days, not to be exceeded).7,8

                                                                                                                                                                                                4 “Provisional Assessment of Recent Studies on Health Effects of Particulate Matter Exposure; National Center for 

Environmental Assessment, Office of Research and Development, U.S. Environmental Protection Agency; Research 

Triangle Park, NC 27711; EPA/600/R-06/063; July 2006.

5

 62 FR 38652-690, July 18, 1997. 

6

 Health Assessment Document for Diesel Engine Exhaust. United States Environmental Protection Agency, Office 

of Research and Development, National Center for Environmental Assessment, Washington, DC, EPA/600/8-

90/057F, May 1, 2002. 

7

 62 FR 38652-760, July 18, 1997. 
3 

Simultaneously, the EPA established secondary (welfare-based) PM2.5 standards identical to the primary 

standards. These standards are hereafter referred to as the 1997 PM2.5 standards. The EPA set the PM2.5

standards with 24-hour and annual averaging times to protect against effects from short- and long-term 

exposure identified by a number of published epidemiological studies. 

A number of events delayed implementation of the 1997 PM2.5 standard.9

 Specifically, the EPA’s 1997 

standards were challenged by the American Trucking Association, the U.S. Chamber of Commerce, and 

other state and business groups. The Transportation Equity Act for the Twenty-first Century (TEA-21) 

revised the deadline to publish nonattainment designations in order to provide additional time to collect 

three years of air quality monitoring data. In February 2001, the Supreme Court upheld the EPA’s 

authority under the Clean Air Act to set NAAQS that protect the American public from the harmful 

effects of air pollution. The Supreme Court also sent the case back to the D.C. Circuit Court of Appeals 

to resolve several additional issues. In March 2002, the D.C. Circuit Court addressed all remaining legal 

challenges to the EPA’s 1997 ambient air quality standards for PM2.5. 

On December 17, 2004, the EPA finalized attainment/ nonattainment designations for the 1997 PM2.5

standards, which became effective on April 5, 2005.10 EPA determined that air quality in Connecticut 

complied with the 1997 24-hour PM2.5 NAAQS, but that emissions from Fairfield and New Haven 

Counties contributed to measured violations of the annual PM2.5 NAAQS in New York City. As a result, 

EPA included those two Connecticut counties in a multi-state nonattainment area also comprised of the 

New York and New Jersey counties that make up the New York City Metropolitan Area. The multi-state 

NY-NJ-CT nonattainment area is depicted in Figure 1-1. The three affected states were responsible for 

developing and coordinating revisions to their respective air quality State Implementation Plans (SIPs) to 

provide for attainment of the 1997 annual PM2.5 NAAQS by the 2010 attainment deadline. Connecticut 

submitted an attainment demonstration SIP to EPA on November 18, 2008 for the 1997 annual PM2.5 

NAAQS.11 See Section 6.5 for further discussion related to that attainment demonstration. 

                                                                                                                                                                                                8

 The EPA also revised the PM10 NAAQS by revising the 24-hour form of the PM10 standard to the 99th percentile 

averaged over 3 years but retaining the 24-hour PM10 level (i.e., 150 mg/m3) (62 FR 38652 (July 18, 1997)). In 

2006, the EPA revoked the annual PM10 standard (71 FR 61144 (October 17, 2006)). Connecticut was not 

designated in nonattainment of the PM10 NAAQS and continues to meet the revised PM10 standards. 9

 EPA Fact Sheet: Areas Designated Nonattainment for the Fine Particle National Air Quality Standards. United 

States Environmental Protection Agency, December 17, 2004, 

http://www.epa.gov/pmdesignations/documents/final/factsheet.htm, accessed June 28, 2007. 10 72 FR 20586-667, April 25, 2007. 

11 Revision to Connecticut’s State Implementation Plan: Annual PM2.5 Attainment Demonstration; Connecticut 

Department of Environmental Protection; November 18, 2008. 
4 

Figure 1.1 The NY-NJ-CT Annual and 24-hour PM2.5 Nonattainment Areas 
5 

1.2.2 2006 PM2.5 NAAQS 

Meanwhile, as required by Clean Air Act (CAA) section 109(d)(1) and governed by a March 2003 

consent decree reached with national environmental organizations, EPA conducted a review of more 

recent health effects studies to assess the adequacy of the 1997 PM2.5 NAAQS. As result of that review, 

EPA promulgated12 revised NAAQS for PM2.5. The EPA retained the annual PM2.5 standard of 15 μg/m3

and revised the 24-hour PM2.5 standard, changing it from 65 μg/m3

 to 35 μg/m3. The effective date for 

the new 24-hour PM2.5 standard became December 18, 2006. In December 2007, Connecticut submitted a 

recommendation that New Haven and Fairfield Counties be designated nonattainment for the PM2.5 24-

hour NAAQS based on an analysis of monitored data for the 2004-2006 period. On November 13, 2009, 

EPA published final designations, effective December 13, 2009,13 including those two counties in a NYNJ-CT 24-hour PM2.5 nonattainment area (see Figure 1.1). EPA designated the remainder of the state as 

unclassifiable/attainment. 

As described in Section 2, PM2.5 air quality has improved significantly over the last decade due to 

emissions reductions resulting from various federal, regional and state control measures. Monitors 

throughout the NY-NJ-CT area are currently measuring compliance with both the 1997 and 2006 PM2.5 

NAAQS, meeting one of several eligibility requirements for redesignation to attainment status for both 

the annual and 24-hour standards. Other eligibility requirements are outlined below. 

1.3 Required Elements for PM2.5 Redesignation 

Section 107(d) (3) (E) of the CAA provides the mechanism for EPA to redesignate an area from 

nonattainment to attainment. Redesignation is contingent upon the EPA Administrator finding that: 

• The area has attained the subject NAAQS; 

• The applicable implementation plan for the area is fully approved under CAA section 110(k); 

• The State containing such area has met all requirements applicable to the area under CAA section 

110 and part D; 

• The improvement in air quality is due to permanent and enforceable emission reductions; 

• The area has a fully approved a maintenance plan meeting CAA section 175A requirements. 

EPA has provided guidance on redesignation in the General Preamble for the Implementation of title I of 

the CAA Amendments of 1990 (April 16, 1992, 57 FR 13498, and supplemented on April 28, 1992, 57 

FR 18070) and has provided further guidance on processing redesignation requests in the following 

documents: 

• “Procedures for Processing Requests to Redesignate Areas to Attainment”; Memorandum from 

John Calcagni, Director, Air Quality Management Division; September 4, 1992. 

• “State Implementation Plan (SIP) Actions Submitted in Response to Clean Air Act (CAA) 

Deadlines”; Memorandum from John Calcagni, Director, Air Quality Management Division; 

October 28, 1992. 

                                                           

12 71 FR 61144, October 17, 2006. 

13 74 FR 58688, November 13, 2009. 
6 

• “Part D New Source Review (Part D NSR) Requirements for Areas Requesting Redesignation to 

Attainment”; Memorandum from Mary D. Nichols, Assistant Administrator for Air and 

Radiation; October 14, 1994. 

The remainder of this TSD provides information describing how Connecticut’s portion of the NY-NJ-CT 

nonattainment area meets these requirements for redesignation to attainment for both the 1997 annual and 

2006 24-hour PM2.5 NAAQS. Section 2 provides a review of monitored PM2.5 data, analyzing trends and 

showing that Connecticut’s monitors comply with the NAAQS. Section 3 documents that Connecticut’s 

SIP meets all applicable CAA Section 110 and part D requirements. Section 4 describes the regulatory 

control programs that have produced the improvements in PM2.5 air quality. Section 5 presents the 

maintenance plan for the CT portion of the NY-NJ-CT area, addressing each of the required elements of 

CAA Section 175A, including transportation conformity emission budgets that will be used in the 

development of future transportation plans by the Connecticut Department of Transportation (CTDOT) 

and affected Metropolitan Planning Organizations (MPO) in the area. Section 6 summarizes the TSD, 

requesting EPA action to redesignate the area to attainment. Several appendices are also included, 

providing supporting details for the previous sections. 
7 

Chapter 2 Demonstration of Attainment of the PM2.5 Standards 

This section documents that the 1997 annual and 2006 24-hour (daily) NAAQS for PM2.5 have been 

attained at all monitors located throughout the NY-NJ-CT nonattainment area. Measured attainment of 

the NAAQS is a key factor in meeting the eligibility requirements of CAA section 107(d)(3)(E) for 

redesignation to attainment. The EPA has already finalized a finding that the area has attained the annual 

PM2.5 NAAQS.14 On February 8, 2011, CT DEEP made a formal request15 to EPA to make a similar 

determination that the NY-NJ-CT non-attainment area has attained the 2006 24-hour NAAQS for PM2.5. 

EPA is currently considering this request. An analysis of relevant monitoring data is provided below, 

with a focus on Connecticut’s monitoring network.16

2.1 Monitoring Network 

The CT DEEP maintains a comprehensive network of PM2.5 air quality monitors located throughout 

Connecticut with the primary objective being to determine compliance with the PM2.5 NAAQS. The CT 

DEEP submits network reviews to the EPA Region 1 annually, demonstrating that air monitoring 

operations meet or surpass all applicable federal requirements. Figure 2.1 is a map illustrating the portion 

of Connecticut within the NY-NJ-CT nonattainment area and the locations of Connecticut’s federal 

reference method (FRM) PM2.5 monitors, as of the end of 2010. CT DEEP continues to operate these 

eleven FRM PM2.5 sites, with seven of the monitors located in Connecticut’s portion of the nonattainment 

area. In addition, in 2009, CT DEEP shut down two sites in the City of New Haven that were operating 

as special purpose monitors. PM2.5 levels at those sites were lower than measurements at the remaining 

two sites in the city. 

2.2 Data Handling and Quality Assurance 

State air monitoring data are submitted to EPA’s data repository called the Air Quality System (AQS). 

All Connecticut data described in this section are included in AQS and have been quality assured, 

meeting the requirements specified in Title 40 of the Code of Federal Regulations (CFR) Part 58 

Appendix A. The completeness criteria for ambient monitoring data are specified in 40 CFR, Part 50, 

National Primary and Secondary Ambient Air Quality Standards: Appendix N. A minimum completeness 

of 75 percent per quarter for each year period is required at each monitoring site. Data completeness 

information is presented in Table 2.1. Six of Connecticut’s current seven PM2.5 monitors located 

                                                           

14 75 FR 69589, November 15, 2010. EPA’s “clean data” finding established that the area is measuring compliance 

with the NAAQS, although the area remains classified as nonattainment until EPA approves a redesignation request 

documenting that all CAA sections 107(d)(3)(E) have been satisfied. 

15 Clean Data Request Letter for 24-hr PM2.5 NAAQS, February 8, 2011. 16 Design values for monitors in the NY and NJ portions of the nonattainment area are also summarized in this 

section. Both NY and NJ have indicated their intention to submit similar PM2.5 redesignation requests, which will 

include more detailed descriptions of each state’s monitoring network and data trends. 
8 

Figure 2.1 Connecticut’s PM2.5Monitoring Network
9 

SITE 

% 

Complete 

2008 Qtr1

% 

Complete 

2008 Qtr2

% 

Complete 

2008 Qtr3

% 

Complete 

2008 Qtr4

% 

Complete 

2009 Qtr1

% 

Complete 

2009 Qtr2

% 

Complete 

2009 Qtr3

% 

Complete 

2009 Qtr4

% 

Complete 

2010 Qtr1

% 

Comp

2010 Q

Bridgeport (090010010) 87% 100% 81% 90% 87% 97% 93% 90% 97% 100% Danbury (90011123) 94% 97% 94% 97% 93% 97% 93% 100% 90% 100% Norwalk (090013005) 90% 97% 90% 87% 90% 90% 93% 97% 57%* 100% Westport (090019003) 84% 100% 99% 99% 84% 93% 99% 86% 100% 97% New Haven Firehouse (090090026) 100% 100% 97% 97% 100% 100% 100% 100% 37%** New Haven Criscuolo (090090027) 96% 97% 95% 100% 94% 99% 98% 100% 98% 99% New Haven State Street (090091123) 100% 100% 87% 100% 100% 100% 100% 94% 100% 100% New Haven Ag Station (090092008) 100% 100% 87% 83% 87% 100% 100% 100% 37%** Waterbury (090092123) 97% 100% 100% 100% 100% 87% 100% 100% 100% 100% * Data incomplete due to roof construction. ** Site removed 2/1/2010. 

Table 2.1 Connecticut PM2.5 Monitors: Data Completeness by Quarter 2008 – 2010
10 

in the NY-NJ-CT nonattainment area met the completeness criteria for the 2008-2010 period. The 

Norwalk monitor was temporarily removed during the first quarter of 2010 to allow roof 

repair/construction. Historically, measured values at the Norwalk site have been among the lowest in 

Connecticut’s portion of the NY-NJ-CT area. 

2.3 PM2.5 Monitoring Data Analysis 

Data from air quality monitors are used to calculate design values (DV)17 at each site. The monitor with 

the highest DV dictates whether the area complies with the NAAQS. For the annual PM2.5 NAAQS, the 

annual DV for each monitor is defined as the three-year average of valid annual means. When calculating 

an annual DV, intermediate calculations are not rounded, while final values are rounded to the nearest 0.1 

μg/m3

. Rounded values at or below 15.0 μg/m3 meet the standard. Rounded values equal to or greater 

than 15.1 μg/m3 exceed the standard. 

The design value for the 24-hour NAAQS is calculated for each site as the three-year average of the 

annual 98th percentile 24-hour average values. When calculating a monitor’s 24-hour DV, intermediate 

calculations are not rounded, while final values rounded to the nearest 1 μg/m3

. Rounded values at or 

below 35 μg/m3 meet the standard. Rounded values equal to or greater than 36 μg/m3 exceed the standard. 

Current (i.e., 2010) PM2.5 design values throughout the NY-NJ-CT nonattainment area are in compliance 

with both the annual NAAQS of 15.0 μg/m3

 and the 24-hour NAAQS of 35 μg/m3, as shown in Figures 

2.2 and 2.3, respectively. The maximum 2010 DVs measured anywhere in the NY-NJ-CT area are 12.5 

μg/m3

 for the annual standard (Morrisania monitor in the Bronx, NY) and 30 μg/m3 for the 24-hour 

NAAQS (Elizabeth Turnpike site in New Jersey). 

PM2.5 air quality has improved significantly over the last decade in Connecticut and throughout the NYNJ-CT nonattainment area. Annual design values for 2007 through 2010 are summarized in Table 2.2 for 

monitors in Connecticut’s portion of the NY-NJ-CT nonattainment area. Annual DVs at each 

Connecticut site have complied with the annual PM2.5 NAAQS throughout the period, with maximum 

DVs in Connecticut of 13.2 μg/m3

 in 2007, 12.4 μg/m3 in 2008, 11.4 μg/m3 in 2009 and 10.3 μg/m3 in 

2010. Maximum DVs anywhere in the NY-NJ-CT area were 15.9 μg/m3

 in 2007, 14.3 μg/m3 in 2008, 

13.9 μg/m3

 in 2009 and 12.5 μg/m3 in 2010, indicating that the NY-NJ-CT area first achieved attainment 

levels of the annual NAAQS in 2008. 

Table 2.3 summarizes 24-hour design values for 2007 through 2010 for monitors in Connecticut’s portion 

of the NY-NJ-CT nonattainment area. Maximum 24-hour DVs for the Connecticut monitors were 36 

μg/m3

 in 2007, 34 μg/m3 in 2008, 31 μg/m3 in 2009 and 29 μg/m3 in 2010. Maximum DVs in the

                                                           

17 A basic summary of design value calculations is provided here. For a more complete description, see 40 CFR Part 

50 Appendix N: Interpretation of the National Ambient Air Quality Standards for PM2.5. 
11 

Figure 2.2 2010 Annual Design Values
12 

Figure 2.3 2010 24-hour Design Values
13 

Table 2.2 Annual PM2.5 Design Values1 in Connecticut’s Portion of the 

NY-NJ-CT Nonattainment Area2

 (μg/m3) 

Site 2007 2008 2009 2010 

Bridgeport (09-001-0010) 13.2 12.4 11.3 10.0 

Danbury (09-001-1123) 12.6 12.0 11.0 10.0 

Norwalk (09-001-3005) 12.3 11.8 11.1 10.0 

Westport (09-001-9003) 11.3 10.6 10.0 9.2 

New Haven Fire House (09-009-0026) 12.1 11.6 10.8 Removed3

New Haven Criscuolo (09-009-0027) 12.3 11.7 10.8 10.0 

New Haven State St (09-009-1123) 12.8 12.2 11.4 10.3 

New Haven Ag Station (09-009-2008) 11.1 10.7 9.9 Removed3

Waterbury (09-009-2123) 12.6 11.9 11.0 10.1 

Table 2.3 24-hour PM2.5 Design Values1 in Connecticut’s Portion of the 

NY-NJ-CT Nonattainment Area2

 (μg/m3) 

Site 2007 2008 2009 2010 

Bridgeport (09-001-0010) 35 33 31 28 

Danbury (09-001-1123) 33 31 29 27 

Norwalk (09-001-3005) 34 31 29 26 (Inc4) 

Westport (09-001-9003) 32 30 29 27 

New Haven Fire House (09-009-0026) 34 32 30 Removed3

New Haven Criscuolo (09-009-0027) 35 33 31 29 

New Haven State Street (09-009-1123) 36 34 31 29 

New Haven Ag Station (9-009-2008) 32 29 27 Removed3

Waterbury (09-009-2123) 35 32 30 27 

Notes for both tables:

1

 The annual PM2.5 NAAQS is 15.0 μg/m3. The 24-hour PM2.5 NAAQS is 35 μg/m3. 2 Data from EPA’s design value website: http://www.epa.gov/airtrends/values.html 3

 These sites were removed in 2010 after measuring lower values than other New Haven sites. 4

 The Norwalk site had one incomplete calendar quarter in 2010 (less than 75% data capture), due to roof 

construction that required temporary monitor removal. 
14 

NY-NJ-CT nonattainment area were 41 μg/m3 in 2007, 38 μg/m3 in 2008, 33 μg/m3 in 2009 and 30 μg/m3

in 2010. Tables 2.2 and 2.3 demonstrate that Connecticut’s portion of the nonattainment area have been 

in compliance with the 24-hour NAAQS since 2008, while the NY-NJ-CT area as a whole first achieved 

attainment levels in 2009. 

The overall downward trend in PM2.5 concentrations is evident in the 10-year DV trend plots displayed in 

Figures 2.4 through 2.9. Figures 2.4 through 2.6 respectively show the significant decline in annual DVs 

in the Connecticut, New York and New Jersey portions of the nonattainment area during the 2001-2010 

period. Similar trends are obvious in Figures 2.7 through 2.9, which depict 24-hour DVs in each state’s 

portion of the nonattainment area. See Section 4 for a discussion of national, regional and state emission 

control programs that have prompted the improvements in PM2.5 air quality. Existing control programs 

are expected to provide further air quality improvements through the maintenance period. 
15 

Figure 2.4 Annual Design Value Trends for Monitors in Connecticut’s Portion of the NY-NJ-C

02468

1012141618

2001 2002 2003 2004 2005 2006 2007 2008 2009 

μg/m

3

Connecticut Annual PM2.5 Design Values 2001‐2010

Bridgeport (09‐001‐0010) Danbury (09‐001‐1123)Stamford HS (09‐001‐2124) Norwalk (09‐001‐3005)Westport (09‐001‐9003) New Haven Fire House (09‐009‐0026)New Haven Criscuolo (09‐009‐0027) New Haven State St (09‐009‐1123)New Haven Ag Station (09‐009‐2008) Waterbury (09‐009‐2123)Hamden Millrock (09‐009‐9005)

Annual NAAQS
16 

Figure 2.5 Annual Design Value Trends for Monitors in New York’s Portion of the NY-NJ-CT Area 

02468

101214161820

2001 2002 2003 2004 2005 2006 2007 2008 2009 

μg/m

3

New York Annual PM2.5 Design Values 2001‐2010

New York Morrisania (36‐005‐0080) Botanical Gardens (36‐005‐0083)New York IS52 (36‐005‐0110) Botanical Gardens Pfizer (36‐005‐0133)New York PS321 (36‐047‐0076) New York JHS126 (36‐047‐0122)Cedarhurst Hempstead (36‐059‐0008) New York PS59 (36‐061‐0056)Canal Street PO (36‐061‐0062) New York JHS45 (36‐061‐0079)New York PS19 (36‐061‐0128) New York PS124 (36‐061‐0134)Newburgh (36‐071‐0002) New York Queens College (36‐081‐0124)Port Richmond (36‐085‐0055) New York Susan Wagner (36‐085‐0067)Babylon MAM (36‐103‐0001) Babylon (36‐103‐0002)Mamaroneck (36‐119‐1002)

Annual NAAQS
17 

Figure 2.6 Annual Design Value Trends for Monitors in New Jersey’s portion of the NY-NJ-CT 

02468

101214161820

2001 2002 2003 2004 2005 2006 2007 2008 2009 

μg/m

3

New Jersey Annual PM2.5 Design Values 2001‐2010

Fort Lee (34‐003‐0003)Newark (34‐013‐0015)Jersey City (34‐017‐1003)Union City (34‐017‐2002)Trenton (34‐021‐0008)Washington Crossing (34‐021‐8001)North Brunswick Township (34‐023‐0006)Morristown (34‐027‐0004)Chester (34‐027‐3001)Paterson (34‐031‐0005)

Annual NAAQS
18 

Figure 2.7 24-hour Design Value Trends for Monitors in Connecticut’s portion of the NY-NJ-C

05

1015202530354045

2001 2002 2003 2004 2005 2006 2007 2008 2009 

μg/m

3

Connecticut 24‐hr PM2.5 Design Values 2001‐2010

Bridgeport (09‐001‐0010) Danbury (09‐001‐1123)Stamford HS (09‐001‐2124) Norwalk (09‐001‐3005)Westport (09‐001‐9003) New Haven Fire House (09‐009‐0026)New Haven Criscuolo (09‐009‐0027) New Haven State St (09‐009‐1123)New Haven Ag Station (09‐009‐2008) Waterbury (09‐009‐2123)Hamden Millrock (09‐009‐9005)

24‐hr NAAQS
19 

Figure 2.8 24-hour Design Value Trends for Monitors in New York’s portion of the NY-NJ-C

05

101520253035404550

2001 2002 2003 2004 2005 2006 2007 2008 2009 

μg/m

3

New York 24‐hr PM2.5 Design Values 2001‐2010

New York Morrisania (36‐005‐0080) Botanical Gardens (36‐005‐0083)New York IS52 (36‐005‐0110) Botanical Gardens Pfizer (36‐005‐0133)New York JHS126 (36‐047‐0122) Cedarhurst Hempstead (36‐059‐0008)New York JHS45 (36‐061‐0079) New York PS19 (36‐061‐0128)New York PS124 (36‐061‐0134) New York Queens College (36‐081‐0124)Port Richmond (36‐085‐0055) New York Susan Wagner (36‐085‐0067)Babylon (36‐103‐0002) Mamaroneck (36‐119‐1002)New York PS321 (36‐047‐0076) Babylon MAM (36‐103‐0001)Newburgh (36‐071‐0002) New York PS59 (36‐061‐0056)Canal Street PO (36‐061‐0062)

24‐hr NAAQS
20 

Figure 2.9 24-hour Design Value Trends for Monitors in New Jersey’s portion of the NY-NJ-

05

101520253035404550

2001 2002 2003 2004 2005 2006 2007 2008 2009 

μg/m

3

New Jersey 24‐hr PM2.5 Design Values 2001‐2010

Fort Lee (34‐003‐0003) Newark (34‐013‐0015)Jersey City (34‐017‐1003) Union City (34‐017‐2002)Trenton (34‐021‐0008) Washington Crossing (34‐021‐8001)North Brunswick Township (34‐023‐0006) Morristown (34‐027‐0004)Chester (34‐027‐3001) Paterson (34‐031‐0005)Elizabeth Turnpike (34‐039‐0004) Elizabeth Downtown (34‐039‐0006)Rahway (34‐039‐2003)

24‐hr NAAQS
21 

Chapter 3 Applicable Requirements Under CAA Section 110 and Title 1 Part D

As a precondition to redesignating a nonattainment area to attainment, the CAA requires EPA to 

determine that the state has met all applicable requirements under section 110 and part D of title I of the 

CAA (per CAA section 107(d)(3)(E)(v)) and that the state has a fully approved SIP under section 110(k) 

for the area (per CAA section 107(d)(3)(E)(ii)). In previous PM2.5 redesignation approvals for other 

areas,18 EPA has described the elements that must be in place to satisfy each of these requirements, 

differentiating between the elements that are applicable for purposes of redesignation and those that are 

not. Drawing from these previous EPA rulemakings, this section describes how Connecticut has met the 

relevant requirements. 

3.1 Satisfying Section 110 General SIP Requirements 

Section 110(a) of Title I of the CAA contains the general requirements for a SIP. Section 110(a)(2) 

provides that the implementation plan submitted by a state must have been adopted by the state after 

reasonable public notice and hearing, and, among other things, must: 

• Include enforceable emission limitations and other control measures, means or techniques 

necessary to meet the requirements of the CAA; 

• Provide for establishment and operation of appropriate devices, methods, systems, and procedures 

necessary to monitor ambient air quality; 

• Provide for implementation of a source permit program to regulate the modification and 

construction of any stationary source within the areas covered by the plan; 

• Include provisions for the implementation of part C, Prevention of Significant Deterioration 

(PSD) and part D, New Source Review (NSR) permit programs; 

• Include criteria for stationary source emission control measures, monitoring, and reporting; and 

• Include provisions for air quality modeling; and provide for public and local agency participation 

in planning and emission control rule development. 

Connecticut has submitted “infrastructure SIPs,” addressing each of these CAA section 110(a)(2) 

requirements, for both the 1997 annual19 and 2006 24-hour20 PM2.5 NAAQS. EPA has found 

Connecticut’s infrastructure SIP submittal for the 1997 annual NAAQS to be complete,21 but has not 

taken final action. EPA has not taken any action on the 24-hour PM2.5 infrastructure SIP. Regardless, 

EPA’s previous rulemakings have concluded that, for purposes of redesignation, an area is only subject to 

those section 110 elements connected with nonattainment plan submissions or an area’s attainment status 

because the area will still be subject to all other section 110 elements after redesignation to attainment.

Similarly, CAA section 110(a)(2)(D) requires that SIPs contain measures to prevent sources in a state 

from significantly contributing to air quality problems in another state. EPA’s previous redesignation 

                                                           

18 For examples, see 76 FR 59512 (September 27, 2011), 76 FR 70078 and 76 FR 70091 (both November 10, 2011). 

19 Submitted to EPA on 9/4/2008. 20 Submitted to EPA on 9/18/2009, with supplements submitted on 1/7/2011 and 8/19/2011. 21 73 FR 62902 (October 22, 2008). 
22 

rulemakings have concluded that this requirement is not applicable for purposes of redesignation22

because the transport SIP submittal requirements, where applicable, continue to apply to a state regardless 

of the designation of any one particular area within that state. 

3.2 Satisfying Part D Requirements 

CAA Title I, Part D, Subpart 1 sets forth the basic nonattainment requirements applicable to all 

nonattainment areas. All areas that were designated nonattainment for the 1997 annual or the 2006 24-

hour PM2.5 NAAQS were designated under this subpart of the CAA, and the requirements applicable to 

them are contained in sections 172 and 176. For purposes of evaluating redesignation requests, the 

applicable part D, subpart 1 SIP requirements are contained in sections 172(c)(1)–(9) and in section 176.23

As described in Section 1 of this document, in December 2004, EPA designated the NY-NJ-CT area as 

nonattainment for the 1997 annual PM2.5 NAAQS, triggering the requirement for an implementation plan 

under CAA section 172(b). On April 25, 2007, EPA promulgated its PM2.5 implementation rule,24

providing guidance for states to develop implementation plans for the annual NAAQS. Connecticut 

subsequently submitted an attainment demonstration for its portion of the annual nonattainment area on 

November 18, 2008, meeting the requirements of EPA’s implementation rule and CAA sections 172 and 

176. 

In 2006, EPA promulgated revisions to the PM2.5 NAAQS, lowering the 24-hour standard to 35 μg/m3

. 

Final designations for the revised 24-hour standard became effective in December 2009, retaining the 

same NY-NJ-CT nonattainment boundaries as for the annual NAAQS. Attainment demonstrations 

addressing CAA sections 172 and 176 for the 24-hour NAAQS are due in December 2012. EPA issued 

guidance for implementing the 24-hour NAAQS on March 2, 2012. The requirement for a state to submit 

an attainment demonstration will no longer apply if EPA rules that an area measures attainment of the 

NAAQS (i.e., the area has “clean data” in accordance with 40 CFR 51.1004(c)), or if EPA approves a 

redesignation request for the 24-hour NAAQS before the December 2012 due date. 

Section 2 of this document described how PM2.5 air quality has significantly improved over the last 

decade. In fact, all monitors in the NY-NJ-CT area have complied with both the annual and 24-hour 

NAAQS since 2009. EPA recognized the improvement by promulgating “clean data” findings25 that the 

multi-state nonattainment area has attained the annual NAAQS and that attainment was achieved by April 

5, 2010, as required under the provisions of EPA’s PM2.5 implementation rule. Connecticut has also 

formally requested26 similar “clean data” findings for the 24-hour NAAQS and is awaiting EPA action. 

                                                           

22 Nonetheless, EPA modeling in support of the Cross-State Air Pollution Rule (76 FR 48208, August 8, 2011) 

shows that Connecticut does not significantly contribute to nonattainment or maintenance issues in any other state 

for the 1997 annual and 2006 24-hour PM2.5 NAAQS, thus satisfying CAA section 110(a)(2)(D) requirements. 23 A thorough discussion of the requirements contained in section 172 can be found in the General Preamble for 

Implementation of Title I (see 57 FR 13498, April 16, 1992). The preamble also includes EPA’s view of applicable 

requirements for purposes of evaluating redesignation requests when an area is attaining a standard. 24 72 FR 20664, April 25, 2007. Codified at 40 CFR Part 51, subpart Z. 

25 75 FR 69589, November 15, 2010. See also see 40 CFR 51.1004. 

26 Clean Data Request Letter for 24-hr PM2.5 NAAQS, February 8, 2011. 
23 

As stipulated in 40 CFR 51.1004(c), EPA’s “clean data” finding for the annual NAAQS suspends the 

requirements for Connecticut to submit an attainment demonstration and associated reasonably available 

control measures (CAA section 172(c)(1) and (c)(6)), reasonable further progress requirements 

(172(c)(2)), contingency measures (172(c)(9)), and other planning SIPs related to attainment of the 1997 

PM2.5 annual NAAQS for so long as the area continues to attain that NAAQS. As noted above, 

Connecticut previously submitted all of these CAA section 172 planning elements to EPA for approval as 

part of the attainment demonstration for the annual PM2.5 NAAQS, although EPA has yet to take action 

approving the implementation plan (see Section 6.5 for further discussion related to the attainment 

demonstration). Nonetheless, per the “clean data” finding, and since the NY-NJ-CT area continues to 

measure attainment of the annual PM2.5 NAAQS, the requirement for these implementation plan elements 

remains suspended, and therefore, are not applicable. A similar conclusion would apply for the 24-hour 

NAAQS, assuming EPA approves Connecticut’s pending request for a “clean data” finding, either prior 

to, or along with approval of the redesignation request and maintenance plan. 

Section 172(c)(4) requires the identification and quantification of allowable emissions for major new and 

modified stationary sources in an area, and section 172(c)(5) requires source permits for the construction 

and operation of new and modified major stationary sources in the nonattainment area. EPA has 

previously issued approvals of Connecticut’s new source review (NSR) program.27 In addition, when the 

1997 annual PM2.5 NAAQS was promulgated, EPA allowed states to use the pollutant PM10 as a surrogate 

for PM2.5 in new source review (NSR) permitting programs until certain technical problems were resolved 

and EPA issued guidance for the states. EPA subsequently issued two relevant implementation rules28

and required states to adopt the necessary requirements by July 20, 2012. CT DEEP held a public hearing 

on November 9, 2011, to consider revisions to RCSA sections 22a-174-1 and 22a-174-3a to include 

significant impact levels, significant emissions rates and increments for PM2.5, consistent with EPA’s 

requirements. CT DEEP anticipates that the revised regulations will be submitted as a SIP revision by the end 

of summer 2012, at which point Connecticut will have in place all applicable CAA Section 110 and Title 1 

Part D requirements necessary for PM2.5 redesignation.

EPA has previously ruled that areas need not have a fully approved nonattainment NSR program for 

purposes of redesignation29 since prevention of significant deterioration (PSD) requirements will apply 

after redesignation. Connecticut’s current PSD program will become effective in the Connecticut portion 

of the NY-NJ-CT area upon redesignation to attainment. 

Section 172(c)(7) requires the SIP to meet the applicable provisions of section 110(a)(2). As noted above 

in Section 3.1, EPA’s previous rulemakings have concluded that this requirement is not applicable for 

purposes of redesignation because the transport SIP submittal requirements continue to apply to a state 

regardless of the designation of any one particular area within that state. 

                                                           

27 40 CFR 52.385. 28 73 FR 28321, May 16, 2008 and 75 FR 64864, October 20, 2010. 

29 Memorandum from Mary Nichols, Assistant Administrator for Air and Radiation; “Part D New Source Review 

Requirements for Areas Requesting Redesignation to Attainment”; October 14, 1994, 
24 

Section 176(c) of the CAA requires states to establish criteria and procedures to ensure that federally 

supported or funded activities, including highway projects, conform to the air quality planning goals in 

the applicable SIPs. The requirement to determine conformity applies to transportation plans, programs, 

and projects developed, funded, or approved under Title 23 of the U.S. Code and the Federal Transit Act 

(transportation conformity) as well as to all other federally-supported or funded projects (general 

conformity). EPA interprets the conformity SIP requirements as not applying for purposes of evaluating 

a redesignation request under section 107(d) because state conformity rules are still required after 

redesignation and federal conformity rules apply where state rules have not been approved. Section 5.1.9 

of this document includes transportation conformity budgets that, upon approval by EPA, will be required 

for use in future transportation planning efforts. 

The only remaining part D, subpart 1 element that must be addressed for both the annual and 24-hour 

PM2.5 NAAQS is the section 172(c)(3) requirement for an inventory of actual emissions for the area. 

Included as part of this redesignation request (see Section 5), is a 2007 base year emissions inventory that 

meets the section 172(c)(3) requirement. When EPA approves this inventory, Connecticut’s portion of 

the NY-NJ-CT area will meet the applicable SIP requirements for purposes of redesignation under title I, 

part D of the CAA. 

3.3 Fully Approved SIP Under Section 110(k) 

As described above, consistent with the previous EPA rulemakings approving other PM2.5 redesignation 

requests, when EPA issues final approval of Connecticut’s base year emissions inventory, EPA will have 

fully approved the applicable Connecticut SIP for Connecticut’s portion of the NY-NJ-CT annual and 24-

hour PM2.5 nonattainment areas under CAA section 110(k) for all requirements applicable for purposes of 

redesignation. 
25 

Chapter 4 Permanent and Enforceable Emission Reductions 

CAA section 107(d)(3)(E)(iv) specifies that a nonattainment area cannot be redesignated to attainment 

unless EPA determines that the improvements in air quality are due to permanent and enforceable 

emission reductions. This section documents that reductions in direct PM2.5 and PM2.5 precursor 

emissions (e.g., SO2 and NOx) have occurred in Connecticut and in upwind areas as a result of permanent 

and enforceable federal and state control measures, accounting for the significant improvements realized 

in measured PM2.5 air quality. Post-2002 NOx, SO2 and PM2.5 control measures that have resulted in 

improvements in ambient PM2.5 levels are listed in Table 4.1. Descriptions of the federal and state 

measures follow. 

4.1 Federal Control Measures 

Improvements in Connecticut’s ambient PM2.5 air quality are partially due to federal control programs that 

have reduced emissions in Connecticut and other states. Transported emissions are especially important 

because PM2.5 concentrations in Connecticut are strongly affected by PM2.5 secondary components such as 

sulfates and nitrates that result from precursor emissions of SO2 and NOx from upwind states. Post200230 federal measures that have contributed to measured attainment of the annual and 24-hour PM2.5 

NAAQS are listed in Table 4.1 and described below. 

4.1.1 Tier 2 Vehicle Standards and Gasoline Sulfur Standards 

The federal Tier 2 rule31, promulgated in February 2000, phased in more stringent vehicle emission 

standards between 2004 and 2009, resulting in lower emissions of NOx, PM and sulfur compounds from 

new cars and light duty trucks, including large sport utility vehicles and passenger vans. The final Tier 2 

standards limit NOx levels for new vehicles to an average of 0.07 grams per mile (g/mi), requiring new 

vehicles to be 77% to 95% lower emitting than those on the road prior to the program. The Tier 2 

standards also reduced the sulfur content of gasoline to 30 parts per million (ppm) by 2006, about an 

order of magnitude lower than 2002 levels. Sulfur in gasoline interferes with the operation of catalytic 

converters on vehicles resulting in higher NOx emissions. In addition to facilitating lower emissions from 

new Tier 2 equipped vehicles, the required lower sulfur levels also produced immediate emission 

reductions from older pre-Tier 2 vehicles due to less poisoning of catalysts on those vehicles. Further 

reductions will occur through the maintenance period as vehicle turnover increases the proportion of Tier 

2 vehicles in the fleet. 

                                                           

30 Designations for the 1997 annual PM2.5 NAAQS were based on 2001-2003 monitored data; therefore, reductions 

since 2002 have contributed to measured air quality improvements since that period. 

31 http://www.epa.gov/fedrgstr/EPA-AIR/2000/February/Day-10/a19a.pdf
26 

Table 4.1 Post-2002 Control Measures 

Control Measure PM NOX SO2

Federal Programs

Tier 2 Vehicle Standards and Gasoline Sulfur Standards X X X 

Heavy-Duty Diesel and Gasoline Highway Vehicle Standards X X X 

Motorcycle Exhaust Standards X 

Large Non-road Diesel Engine Standards X X X 

Non-road Spark-Ignition Engines and Recreational Engine 

Standards X X X 

NOx SIP Call X 

CAIR X X 

State Programs

Control of Sulfur Dioxide and Nitrogen Oxide Emissions from 

Power Plants and Other Large Stationary Sources 

RCSA Sections 22a-174-19a and 22a-174-22(e)(3) 

 X X 

The Post-2002 Nitrogen Oxides (NOx) Budget Program 

RCSA Section 22a-174-22b X 

CAIR NOX Ozone Season Trading Program 

RCSA Section 22a-174-22c X 

Outdoor Wood Burning Furnace Restrictions 

Section 22a-174k of the Connecticut General Statutes X 

Improvements in the Control of Particulate Matter and Visible 

Emissions RCSA Section 22a-174-18 X X 

Connecticut Enhanced Inspection and Maintenance Program 

(ASM 2525 final standards and OBD II program) 

RCSA Section 22a-174-27 

 X 

CT’s California Low Emission Vehicle Phase 2 (CALEV2) 

RCSA Section 22a-174-36b X X 

Reductions in NOx emissions from Municipal Waste Combustors 

(Phase 2) RCSA Section 22a-174-38 X 

NSR Permit to Construct and Operate Stationary Sources 

RCSA Section 22a-174-3a X X X 
27 

4.1.2 Heavy-Duty Diesel and Gasoline Highway Vehicle Standards 

New U.S. EPA standards32,33 designed to reduce NOx and VOC emissions from heavy-duty diesel and 

gasoline highway vehicles took effect in 2004 and 2005, respectively. A second phase of standards,34

commencing in 2007, established tighter PM and NOx emission limits for heavy-duty diesel and gasoline 

highway engines and also required highway diesel fuel sulfur content to be reduced by 97% to 15 ppm to 

minimize potential damage to emission control devices. EPA estimates that the total program achieves a 

90% reduction in PM emissions and a 95% reduction in NOx emissions from new engines using low 

sulfur diesel, compared to previous generation engines using higher sulfur content diesel. The reduction 

in fuel sulfur content also provided additional immediate reductions in sulfate particle emissions from all 

on-road diesel vehicles. Further emission reductions will occur through the maintenance period with fleet 

turnover.

4.1.3 Motorcycle Exhaust Standards 

In 2004, EPA published a final rule to implement improved exhaust emission standards on new highway 

motorcycles.35 These exhaust emission standards apply to all 2006 model year and newer motorcycles, 

including scooters and mopeds. In addition, motorcycles with the largest engines are subject to more 

stringent NOx and hydrocarbon standards beginning with the 2010 model year.

4.1.4 Large Non-road Diesel Engine Standards 

In May 2004, EPA expanded on previous requirements36 by adopting a new rule37 establishing tighter 

emission limits for large non-road diesel engines, such as those used in construction, agricultural, and 

industrial equipment, to be phased in between 2008 and 2014. The non-road diesel rule also required 

reductions in the sulfur content of non-road diesel fuel from pre-rule levels of approximately 3,400 ppm 

to 500 ppm by 2006, with a further reduction to 15 ppm by 2010, a total reduction of over 99 percent. 

The combined engine and fuel rules reduced NOx and PM emissions from new large non-road diesel 

engines by over 90%, compared to previous generation non-road engines using higher sulfur content 

diesel fuel. Given the timing of the new requirements, most of the reductions will occur during the 

maintenance period as the fleet of older non-road diesel engines is gradually replaced with the newer, 

lower emitting engines. Nonetheless, the required reduction in fuel sulfur content did yield an immediate 

reduction in sulfate particle emissions from all non-road diesel vehicles.

                                                           

32 http://www.epa.gov/fedrgstr/EPA-AIR/1997/October/Day-21/a27494.htm 33 http://www.epa.gov/fedrgstr/EPA-AIR/2000/October/Day-06/a20144.pdf 34 http://www.epa.gov/fedrgstr/EPA-AIR/2001/January/Day-18/a01a.pdf 35 69 FR 2398; January 15, 2004. See http://www.epa.gov/fedrgstr/EPA-GENERAL/2004/January/Day15/g006.htm

36 http://www.epa.gov/fedrgstr/EPA-AIR/1998/October/Day-23/a24836.htm 37 http://edocket.access.gpo.gov/2004/pdf/04-11293.pdf
28 

4.1.5 Non-road Spark-Ignition Engines and Recreational Engine Standards 

In November 2002, EPA promulgated emission standards38 for groups of previously unregulated non-road 

engines. These engines include large spark-ignition engines such as those used in forklifts and airport 

ground service equipment; recreational vehicles using spark-ignition engines such as off highway 

motorcycles, all-terrain vehicles, and snowmobiles; and recreational marine diesel engines. Emission 

standards from large spark ignition engines were implemented in two tiers, with Tier 1 starting in 2004 

and Tier 2 in 2007. Recreational vehicle emission standards are being phased in from 2006 through 2012. 

Marine diesel engine standards were phased in from 2006 through 2009. With full implementation of the 

entire non-road spark-ignition engine and recreational engine standards, an 80% reduction in NOx is 

expected by 2020, as the affected fleets are gradually replaced. 

4.1.6 NOx SIP Call, CAIR and CSAPR Programs 

In October 1998, EPA issued a NOx SIP Call39 requiring the District of Columbia and 22 states (including 

Connecticut) to reduce emissions of NOx. The program was primarily targeted at securing emission 

reductions from electric generating units (EGUs or power plants) in states that were determined to be 

significantly contributing to violations of the 1-hour ozone NAAQS in other, downwind states. Affected 

states were required to comply with Phase I of the SIP Call beginning in 2003/2004 and Phase II 

beginning in 2007. 

Subsequent to the 1997 revisions to the ozone and PM2.5 NAAQS, EPA promulgated the Clean Air 

Interstate Rule40 (CAIR) in May 2005 and associated Federal Implementation Plans41 (FIPs) in April 2006 

in order to reduce transported SO2 and NOx emissions from 28 states (including Connecticut) and improve 

air quality in many areas across the Eastern United States. However, on July 11, 2008, the United States 

Court of Appeals for the District of Columbia Circuit vacated and remanded both CAIR and the 

associated CAIR FIPs in their entirety.42 EPA petitioned for a rehearing, and the D.C. Circuit issued an 

order in December 2008 remanding CAIR and the CAIR FIPs to EPA without vacatur,43 directing that 

CAIR remain in place in order to ‘‘temporarily preserve the environmental values covered by CAIR’’ 

until EPA replaced it with a rule consistent with the Court’s opinion. 

EPA responded to the Court’s directive in August 2011, finalizing the Cross-State Air Pollution Rule44

(CSAPR) to address interstate transport of emissions and resulting secondary air pollutants and to replace 

CAIR. In response to subsequent challenges to CSAPR, the D.C. Circuit issued a stay45 of CSAPR on 

December 30, 2011, specifying that CAIR requirements remain in place while the Court considers and 

                                                           

38 http://www.epa.gov/fedrgstr/EPA-AIR/2002/November/Day-08/a23801.pdf 39 63 FR 57356; October 27, 1998. See http://www.epa.gov/fedrgstr/EPA-AIR/1998/October/Day-27/a26773a.htm 40 70 FR 25162; May 12, 2005. 

41 71 FR 25328; April 28, 2006. 

42 North Carolina v. EPA, 531 F.3d 836 (D.C. Cir. 2008). 

43 See North Carolina v. EPA, 550 F.3d 1176 (D.C. Cir. 2008). 

44 76 FR 48208; August 8, 2011. 

45 See http://epa.gov/airtransport/pdfs/CourtDecision.pdf. 
29 

rules on pending petitions in the case. CSAPR would retain the CAIR emission reduction requirements46

through 2011, requiring similar or greater emission reductions of SO2 and/or NOx from EGU’s in 28 

eastern states in 2012 and beyond. Assuming CSAPR is ultimately upheld by the Court, the post-2011 

emission reductions will further reduce transport into Connecticut, helping to ensure continued attainment 

through the maintenance period. On March 1,2012, EPA filed its brief defending CSAPR. Oral 

arguments were held on April 13, 2012. 

Because PM2.5 concentrations in Connecticut are significantly impacted by the transport of sulfates and 

nitrates, the area’s air quality is strongly affected by regulation of SO2 and NOx emissions from power 

plants in upwind states. Table 4.2 presents actual EGU emissions data downloaded from EPA’s Clean 

Air Markets Division47 (CAMD) website for the years 2002 and 2007 through 2009, the period when the 

NY-NJ-CT area first attained both the annual and 24-hour PM2.5 NAAQS. EGU emissions are included 

for all states that, according to EPA’s CSAPR modeling,48 are estimated to significantly impact 

Connecticut monitors at a level equal to or exceeding 1% of the annual or 24-hour PM2.5 NAAQS in the 

absence of CAIR or CSAPR. Emissions for 2002 reflect implementation of the federal acid rain program 

and, for states in the Ozone Transport Region, a regional NOx control program that was implemented 

during the late 1990’s. Emissions for 2007 also include reductions implemented under the NOx SIP Call, 

with CAIR Phase 1 NOx requirements reflected by 2009. Although CAIR SO2 limits were not in place 

until 2010, some early reductions were realized by 2009. Overall, the table shows a dramatic decrease in 

EGU emissions across the states impacting Connecticut, totaling 66% reductions in NOx and 48% 

reductions in SO2 emissions between 2002 and 2009. 

4.2 Connecticut Control Measures 

In addition to the federal control measures described above, Connecticut implemented several statespecific programs that contributed to the significant improvements observed in ambient PM2.5 levels. 

Details regarding state measures were provided in Connecticut’s attainment demonstration SIP49 for the 

1997 annual PM2.5 NAAQS. Connecticut’s post-2002 NOx, SO2 and PM2.5 control measures that have 

resulted in improvements in ambient PM2.5 levels are listed in Table 4.1. Descriptions of the state 

measures follow. 

Connecticut requests withdrawal of one control measure cited in the attainment demonstration for the 

1997 annual PM2.5 NAAQS (submitted November 18, 2008). No applications were ever received for a 

general permit issued for distributed generation sources (authorized under CGS 22a-174(k) and section 

102 of Public Act 07-242). The general permit has since expired, with no plans for renewal. Therefore, 

there is no need to include the general permit in the SIP. 

                                                           

46 Note that EPA’s revised technical analysis for CSAPR determined that Connecticut was not contributing to 

downwind attainment issues in any other state, thus Connecticut sources are not subject to CSAPR. However, as 

described in Section 5, Connecticut plans to adopt a rule to ensure that CAIR emission caps are retained in the state. 47 Using CAMD’s “Quick Report” application, specifying state-level annual acid rain program sources for each year 

because 2002 data are not available for the CAIR program sources. Differences are judged to be minimal. 48 http://epa.gov/crossstaterule/pdfs/CSAPR_Ozone%20and%20PM2.5_Contributions.xls 49 PM2.5 Attainment Demonstration SIP submitted to EPA on November 18, 2008. 

See: http://www.ct.gov/dep/cwp/view.asp?a=2684&Q=419074&depNav_GID=1619. 
30 

 

 NOx (tpy) SO2 (tpy) 

State 2002 2007 2008 2009 2002 2007 2008 2009 

CT 5,102 3,739 3,120 1,604 10,814 4,782 3,955 1,754 

GA 146,456 107,471 105,894 57,566 512,654 635,484 514,539 262,258 

IL 174,247 118,230 119,976 72,286 353,699 272,571 257,431 229,364 

IN 281,146 196,553 196,580 110,969 778,868 714,529 595,966 413,726 

KY 198,599 174,841 157,847 78,767 482,653 379,837 344,356 252,002 

MA 28,797 10,368 9,357 7,640 90,727 53,863 46,347 35,182 

MD 71,457 50,121 35,902 16,946 255,360 272,879 227,197 198,254 

MI 132,623 105,862 103,473 78,947 342,999 338,014 326,501 272,621 

MO 139,799 105,921 88,600 53,475 235,532 255,202 258,269 240,202 

NC 145,706 59,418 54,652 38,783 462,993 370,826 227,030 110,948 

NJ 27,960 11,808 9,143 5,219 48,269 34,189 21,204 10,867 

NY 69,665 41,167 31,060 22,587 231,984 107,210 65,427 43,616 

OH 370,497 237,876 235,018 95,785 1,132,069 954,646 709,444 600,687 

PA 200,909 178,656 175,219 110,218 889,766 951,186 831,915 573,619 

TN 155,996 102,886 85,543 27,912 336,995 237,231 208,069 108,042 

VA 78,868 53,488 43,017 25,881 230,846 172,685 125,985 93,163 

WV 225,371 150,849 97,331 36,120 507,110 371,996 301,574 174,583 

Total 2,455,200 1,711,261 1,553,737 842,712 6,905,340 6,129,139 5,067,219 3,622,899 

Change 

vs. 2002 

(tpy) -- -743,939 -901,463 -1,612,488 -- -776,201 -1,838,120 -3,282,441 

% Change 

vs. 2002 -- -30% -37% -66% -- -11% -27% -48% 

Table 4.2 Comparison of Actual EGU Emissions from States Impacting Connecticut’s PM2.5 Air Quality
31 

4.2.1 Control of SO2 and NOx Emissions from Power Plants and Other Large 

Stationary Sources 

The CT DEEP was required by an executive order of the Governor to adopt regulations to reduce 

emissions of SO2 and NOx from major stationary sources, including power plants. In response, 

CT DEEP adopted RCSA section 22a-174-19a and amended section 22a-174-22, in December 

2000, with the requirements phased in from 2002 to 2003. The requirements apply in general to 

the Acid Rain program sources and NOx Budget sources. 

The SO2 emissions reduction requirements include low sulfur fuel requirements (0.3% or 0.5% 

sulfur, by weight, depending on source type) and comparable quarterly average emissions limits. 

Revision to the NOx provisions included the addition of a non-ozone season NOx limit of 0.15 

pounds per MMBtu, which applied to the owners of all sources subject to the NOx Budget 

Program of RCSA section 22a-174-22b. 

4.2.2 The Post-2002 Nitrogen Oxides (NOx) Budget Program 

EPA’s NOx SIP Call of October 1998 led to Connecticut's adoption of its NOx Budget Program under 

RCSA section 22a-174-22b, which was approved by EPA as a SIP strengthening measure on December 

27, 2000.50 RCSA section 22a-174-22b established a statewide NOx budget and NOx allowance trading 

program for large electric generators and other industrial sources beginning with the 2003 ozone season. 

The budget cap was consistent with EPA's NOx SIP Call and the September 1994 OTC Memorandum of 

Understanding establishing the OTC NOx Budget Program (NBP). In Connecticut, the OTC program was 

conducted pursuant to RCSA section 22a-174-22a. Both of these regulations were repealed in 

Connecticut’s CAIR regulation, described below.

4.2.3 CAIR and Connecticut’s CAIR Replacement Rule 

Connecticut complied with EPA’s 2005 promulgation of CAIR by electing to participate in the federal 

CAIR ozone-season NOx trading program, adopting RCSA section 22a-174-22c on September 4, 2007. 

EPA subsequently approved51 the rule on January 24, 2008. Connecticut’s CAIR regulation supplanted 

the previous NOx Budget regulations, which were repealed. All the sources that participated in the RCSA 

section 22a-174-22b NOx budget program are subject to Connecticut’s CAIR ozone season NOx trading 

program, albeit subject to a reduced statewide ozone season budget and a revised allocation system. 

 

As described earlier, in August 2011, EPA publishedCSAPR in the Federal Register52 to comply with the 

Court remand of CAIR. EPA’s updated analysis for CSAPR concluded that Connecticut was not 

                                                           

50 65 FR 81743, December 27, 2000. 51 73 FR 4105; January 24, 2008. 

52 76 FR 48208, August 8, 2011. 
32 

significantly contributing to nonattainment or maintenance issues in any other state, thus CSAPR 

requirements do not apply to sources in Connecticut. Connecticut is obligated to maintain in-state 

emission reductions realized by RCSA section 22a-174-22c, but must revise its regulations due to EPA’s 

exclusion of Connecticut from CSAPR’s interstate trading programs. 

On December 15, 2011, CT DEEP held a hearing on the proposed adoption of a new intrastate ozone 

season nitrogen oxides (NOx) trading program (RCSA section 22a-174-22d), which would replace the 

interstate Clean Air Interstate Rule (CAIR) NOx Trading Program now in effect under RCSA section 22a174-22c when CSAPR is implemented. CT DEEP subsequently submitted the proposed CAIR 

replacement rule to EPA for approval, requesting parallel processing. EPA proposed approval of the rule 

on March 26, 2012 (77 FR 17367). CT DEEP expects to submit the final version of rule to EPA shortly. 

The proposed program is structured similarly to the program now in effect under RCSA section 22a-174-

22c, and EPA will administer the intrastate trading program in a similar manner. The regulated units will 

be subject to an emission budget of 2,691 tons per ozone season, exactly the same state emissions budget 

now in effect under RCSA section 22a-174-22c. As noted earlier, the D.C. Circuit issued a stay of 

CSAPR on December 30, 2011, specifying that CAIR requirements remain in place while the Court 

considers and rules on pending petitions in the case. As a result, the new regulation would be effective 

when CAIR sunsets by federal action after the CSAPR issues are resolved, thereby ensuring that the 

emission reductions originally secured in Connecticut by CAIR are retained into the future. 

4.2.4 Outdoor Wood Burning Furnace (OWBF) Restrictions 

As of July 2005, CGS Section 22a-174k prohibits the construction and use of an OWBF unless the 

OWBF is located more than 200 feet from any residence, meets certain stack height criteria and the owner 

complies with certain operating practices, including a requirement to burn only clean wood. These 

requirements address the siting and operation of these units in a manner that will work to limit exposure 

to particulate matter emissions. 

The statute includes a sunset clause53 that is triggered upon “ ... the effective date of regulations 

promulgated by the United States Environmental Protection Agency to regulate outdoor wood-burning 

furnaces.” EPA is currently considering pursuing adoption of a New Source Performance Standard 

(NSPS) that would include emission limits for OWBFs. The requirements of CGS Section 22a-174k 

would no longer apply upon the effective date of a federal NSPS, if one were eventually adopted in final 

form. 

4.2.5 Improvements in the Control of Particulate Matter and Visible Emissions 

RCSA section 22a-174-18 was revised in 2004 to: (1) improve enforceability of the opacity requirements 

by specifying the form and averaging time of the existing opacity standards for stationary sources and 

                                                           

53 The full text of CGS Section 22a-174k is available at http://www.cga.ct.gov/2011/pub/chap446c.htm#Sec22a-174k.htm.
33 

including provisions specific to sources with continuous emissions monitors; (2) add particulate matter 

standards appropriate to fuel-burning equipment using certain fossil fuels; and (3) add particulate matter 

emissions standards and requirements for stationary reciprocating internal combustion engines. 

 

4.2.6 Connecticut Enhanced I/M (ASM 2525 final standards) and OBD-II 

Enhanced I/M 

In August 2004, CT DEEP updated the motor vehicle emissions testing program standards implemented 

by the Connecticut Commissioner of Motor Vehicles to conform to revisions to the underlying federal 

program standards. Specifically, the revisions to RCSA section 22a-174-27: (1) defined new on-board 

diagnostic test requirements; (2) added new emissions standards for vehicles subject to a pre-conditioned 

two speed idle exhaust emissions test procedure; (3) required ASM 2525 exhaust emission standards 

consistent with federal guidance but for which the federal government has not adopted analogous 

standards; and (4) added new emissions standards for diesel vehicles subject to a modified snap 

acceleration smoke opacity test. 

In 2003, Connecticut began operating a decentralized I/M testing infrastructure through a new I/M 

contractor. The revised I/M program requires the use of the on-board diagnostics II (OBDII) test, the 

ASM 2525 test, the pre-conditioned two-speed idle (PCTSI) test, or one of two types of opacity testing, 

depending on the age, weight and fuel type of each vehicle. Virtually all vehicles that weigh less than 

10,000 pounds (gross vehicle weight rating) and that are between 4 and 25 years of age are subject to the 

program. DEEP filed a SIP revision with EPA on December 20, 2007 to incorporate these changes to the 

I/M program. 

4.2.7 California Low Emission Vehicle 2 (CALEV2) 

The State of Connecticut is implementing the light-duty motor vehicle emission standards of the State of 

California applicable for model year 2008 and later motor vehicles. California’s revision of their Low 

Emission Vehicle (LEV) standards also includes adoption of greenhouse gas emission standards for 

passenger cars, light-duty trucks and medium duty passenger vehicles commencing with 2009 and 

subsequent model year vehicles. The program is implemented through RCSA section 22a-174-36b, 

which was adopted in Connecticut in December 2005.

4.2.8 Reducing NOx Emissions from Municipal Waste Combustors 

Connecticut’s regulation to limit air pollutant emissions from the state’s municipal waste combustor 

(MWC) units is described in the previous section. An October 26, 2000 amendment to RCSA section 

22a-174-38 reduced the NOX emission limits below the 1999 levels beginning May 1, 2003. EPA 

approved the amended regulation and associated emissions reductions for 1-hour ozone NAAQS 

attainment on December 6, 2001.54 

                                                           

54 66 FR 63311, December 6, 2001. 
34 

4.2.9 Conclusions

Connecticut’s attainment demonstration SIP55 for the annual PM2.5 NAAQS included emission reduction 

estimates between 2002 and 2009 resulting from the federal and state control programs cited above. 

Significant annual emission reductions were estimated in Connecticut for direct PM2.5 (679 tons, or 4%), 

NOx (36,166 tons, or 30%) and SO2 (9,233 tons, or 29%) between 2002 and 2009. When paired with the 

upwind impact of the federal controls described previously, the combined emission reductions are 

responsible for the NAAQS-compliant levels of PM2.5 that continue to be measured in Connecticut and 

the rest of the NY-NJ-CT area. 

                                                           

55 Connecticut Attainment Demonstration SIP for the 1997 Annual PM2.5 NAAQS; Technical Support Document 

(Section 5); Submitted to EPA on November 18, 2008. 
35 

Chapter 5 Maintenance Plan 

Section 107(d)(3)(E)(iv) of the CAA stipulates that, for an area to be redesignated to attainment, EPA 

must fully approve a maintenance plan that meets the requirements of section 175A. A state may submit 

both the redesignation request and the maintenance plan at the same time and rulemaking on both may 

proceed on a parallel track. 

 

CAA section 175A establishes the required elements of a maintenance plan for areas seeking 

redesignation from nonattainment to attainment. Under section 175A, the plan must demonstrate 

continued attainment of the applicable NAAQS for at least 10 years after EPA approves an area’s 

redesignation to attainment. The plan must contain additional measures, if any, necessary to ensure such 

maintenance. Eight years after the redesignation approval, the state must submit a revised maintenance 

plan demonstrating that attainment will continue for the 10 years following the initial maintenance period. 

To address the possibility of future NAAQS violations, section 175 also specifies that the maintenance 

plan must contain contingency measures necessary to assure prompt correction of any violation of the 

standard that occurs after redesignation of the area to attainment. 

EPA has provided further guidance56 expanding on the required content of a maintenance plan, explaining 

that a maintenance plan should include the following five elements: 

• An inventory sufficient to ensure attainment; 

• A demonstration that the plan ensures continued maintenance of the NAAQS through a 10 year 

maintenance period commencing when EPA approves the redesignation request; 

• A commitment to maintain an appropriate monitoring network; 

• A method to track the progress of the maintenance plan; and 

• Contingency measures to be implemented if NAAQS violations occur during the maintenance 

period. 

The remainder of this section addresses each of the required elements. The first two elements, the 

attainment inventory and demonstration of continued maintenance, are addressed together in Section 5.1. 

5.1 Attainment Inventory and Demonstration of Continued Maintenance 

EPA’s guidance for maintenance plans calls for states to provide an emissions inventory representative of 

the level of emissions sufficient to attain the NAAQS. In addition, the maintenance plan should include a 

demonstration of continued compliance by showing that future emissions during the maintenance period 

will not exceed the level of emissions in the attainment inventory. 

As previously discussed in Section 2 of this TSD, three-year design values measured in the NY-NJ-CT 

area have shown compliance with the annual NAAQS since 2008 and the 24-hour NAAQS since 2009. 

                                                           

56 ”Procedures for Processing Requests to Redesignate Areas to Attainment”; Memorandum from John Calcagni, 

Director, Air Quality Management Division; September 4, 1992. 
36 

In the Connecticut portion of the area, annual compliance extends back to at least 2001, while compliance 

with the 24-hour NAAQS was initially achieved in 2008. As a result, 2007 was selected as an appropriate 

year for the attainment inventory. The end of the maintenance period was established as 2025, consistent 

with the CAA section 175A(a) requirement that the plan provide for maintenance of the NAAQS for at 

least 10 years after EPA formally approves the redesignation request. Emission estimates were developed 

for direct PM2.5, as well as for the most important PM2.5 precursors, SO2 and NOx. As described below, 

emissions are projected to decrease from the levels in the 2007 attainment inventory through the end of 

the maintenance period in 2025, including in the selected interim year of 2017, thus providing for 

continuous maintenance of the NAAQS. 

Annual inventories used for the PM2.5 redesignation effort were developed as an extension of regional 

efforts in the Mid-Atlantic/Northeast Visibility Union (MANE-VU) area to create inventories for use in 

photochemical modeling for the 2008 ozone NAAQS, potential future revisions to the PM2.5 NAAQS, and 

regional haze SIPs. Representatives from MANE-VU states and the Mid-Atlantic Regional Air 

Management Association (MARAMA), with contractor support, were already in the process of 

developing multi-pollutant inventories for 2007, 2017 and 2020 for the MANE-VU states (Connecticut, 

Delaware, the District of Columbia, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New 

York, Pennsylvania, Rhode Island, and Vermont) and Virginia. When the opportunity arose in several 

areas to pursue PM2.5 redesignation, MARAMA took the lead on coordinating with affected states to 

create a supplemental inventory for 2025 and to make appropriate modifications to the 2007 inventory for 

use in the redesignation effort. 

The paragraphs below summarize the inventory development process. Further inventory details are 

provided in the following appendices prepared by MARAMA’s contractor in cooperation with the 

MANE-VU states. 

Appendix A: VERSION 3.3 Technical Support Document for the Development of the 2007 Emission 

Inventory for Regional Air Quality Modeling in the Northeast/Mid-Atlantic Region; Prepared for 

MARAMA by AMEC Environment & Infrastructure and SRA International, Inc.; January 23, 2012. 

Appendix B: VERSION 3.3 Technical Support Document for the Development of the 2025 Emission 

Inventory for PM Nonattainment Counties in the MANE-VU Region; Prepared for MARAMA by AMEC 

Environment & Infrastructure and SRA International, Inc.; January 23, 2012. 

Appendix C: VERSION 3.3 Technical Support Document for the Development of the 2017 / 2020 

Emission Inventories for Regional Air Quality Modeling in the Northeast / Mid-Atlantic Region; 

Prepared for MARAMA by AMEC Environment & Infrastructure and SRA International, Inc.; January 

23, 2012. 

Detailed inventory data and other related documentation can be accessed through MARAMA’s ftp 

website. See Appendix D for directions for accessing that site. 
37 

5.1.1 Pollutants 

The inventories developed for the PM2.5 redesignation effort include directly emitted PM2.5 and PM2.5-

precursors (i.e., NOx and SO2). The PM2.5 species in the inventory are categorized as particles with an 

aerodynamic diameter less than or equal to a nominal 2.5 micrometers (PM25-PRI), which includes both 

condensable particles (PM-CON) and filterable particles (PM25-FIL). 

5.1.2 Source Categories 

Emission estimates were developed for sources in the following categories: 

• Electric Generating Unit (EGU) Point Sources are units that generate electric power and sell 

most of the power generated to the electrical grid. 

• Non-EGU Point Sources are individual industrial, commercial, and institutional facilities and are 

further subdivided by stack, emission unit, and emission process. 

• Stationary Area Sources include small, non-permitted sources that in aggregate may contribute 

significant emissions. Examples include small industrial/commercial facilities, residential 

heating furnaces, and road dust re-entrainment. 

• Non-road Mobile Sources include internal combustion engines used to propel marine vessels, 

airplanes, and locomotives, or to operate equipment such as forklifts, lawn and garden equipment, 

portable generators, etc. For activities other than marine vessels, airplanes, and railroad 

locomotives (MAR), the inventory was developed using the most current version of EPA’s 

NONROAD model as embedded in the National Mobile Inventory Model (NMIM). Because the 

NONROAD model does not include emissions from MAR sources, these emissions were 

estimated based on data and methodologies used in recent EPA regulatory impact analyses. 

• On-road Mobile Sources are sources of air pollution from internal combustion engines used to 

propel cars, trucks, buses, and other vehicles on public roadways. Emission projections for onroad mobile sources were developed using EPA’s Motor Vehicle Emission Simulator (MOVES) 

model. 

Biogenic/geogenic emissions are not included in this inventory. 

5.1.3 Geographic and Temporal Resolution 

The MANE-VU PM2.5 redesignation inventories were prepared only for those areas classified as 

nonattainment for the annual or 24-hour PM2.5 NAAQS (e.g., Fairfield County and New Haven County in 

Connecticut). The inventories were developed at the county level for the area and mobile source 

categories and at the process level for point sources categories, then summed to the county level. 

 

Discussions between MANE-VU states and EPA concluded that the use of annual inventories would also 

be appropriate for demonstrating continued compliance with the 24-hour PM2.5 NAAQS during the 

maintenance period if monitoring data analysis for an area showed that elevated 24-hour PM2.5 levels 

occur in multiple seasons. CT DEEP performed such an analysis, summarized in Appendix E, and found 

that elevated PM2.5 levels do occur in multiple seasons (primarily summer and winter) in Connecticut; 
38 

therefore, annual inventories can be used to demonstrate compliance with both the annual and 24-hour 

NAAQS during the maintenance period. 

5.1.4 Point Source Inventory Procedures

As part of the regional MANE-VU inventory effort, CT DEEP supplied MARAMA with actual 2007 

emissions for all EGU and non-EGU point sources. For consistency in both reporting emissions and 

projecting emissions to the future, states agreed to group as EGU sources only those EGU sources that 

report hourly emissions to EPA’s CAMD database. All other point sources (including non-EGUs in 

CAMD, small non-CAMD EGUs and all other non-EGUs) were grouped as non-EGU point sources. 

Quality Assurance

The point source inventory underwent a multi-step iterative review process to ensure data quality.57 The 

review process included: 

• EPA’s Basic Format and Content Checker tool was used to verify format and check for referential 

integrity and duplicate record issues; 

• Facility-level comparisons were made between the 2007 source list and the 2002 MARAMA 

inventory to identify and verify/correct any facilities included in only one of those inventories; 

• For facilities included in both inventories, large emission changes between 2002 and 2007 were 

examined for reasonableness, with corrections made if warranted; 

• Crosswalks were developed to compare and verify linkages between the CAMD and statesupplied NIF source data sets. 

• Source location coordinates were checked to ensure location in the correct county; 

• Source files were made available for stakeholder review, with requested changes evaluated by 

states for possible revisions. 

The quality assurance process resulted in several changes to CT DEEP’s original 2007 point source 

submittal. Revisions included corrections for PM-related pollutant codes for some combustion sources 

and recalculation of actual emissions where rule effectiveness should not have been included. In addition, 

stakeholder comments resulted in minor revisions to emission estimates for two facilities. 

PM Augmentation 

Similar to other states, Connecticut’s 2007 point source inventory, as supplied to MARAMA, did not 

include all components of PM emissions (i.e., PM-PRI, PM-FIL, PM-CON). The contractor applied PM 

augmentation procedures58 to calculate missing components, with different procedures used for EGU and 

non-EGU sources. The EGU process used updated condensable emission factors, with preference given 

to the use of emission factors developed from EGU source tests where nitrogen purging occurred so as to 

minimize overestimation of condensable emissions due to sulfur artifact. For non-EGU sources, PM 

augmentation employed essentially the same process used in developing the 2002 MANE-VU Version 3 

inventory. 

                                                           

57 See Section 2.1 through 2.7 of Appendix A for a full description of point source quality assurance procedures. 58 See Section 2.2 of Appendix A for a more complete explanation of PM augmentation procedures. 
39 

Banked Emission Reduction Credits 

CT DEEP maintains a registry of continuous emission reduction credits (CERCs) for potential use as 

offsets in new source review permits. In order to preserve potential future use of these credits, any 

CERCs initiated prior to the 2007 attainment inventory year must be accounted for in the 2007 and future 

year inventories that are included in this maintenance plan. Table 5-1 summarizes CERCs that have been 

included in the inventories. These emissions are reflected in the non-EGU inventory on a county-bycounty basis under source classification code (SCC) 23-99-000-000. All county-level emissions were 

assigned to a fictitious facility located at the county centroid with an assumed release height of 30 feet. 

Table 5.1 CT DEEP Banked Emission Reduction Credits 

DEEP Emission Reduction Credit Bank of 

NOx Emissions Included in 

2007, 2017 and 2025 Inventories FIPS 

NOx 

(tpy) 

Totals by 

County*: 

Fairfield 09001 392.0 

Hartford 09003 0.0 

Litchfield 09005 0.0 

Middlesex 09007 23.0 

New Haven 09009 476.8 

New London 09011 179.0 

Tolland 09013 0.0 

Windham 09015 247.0 

* Fairfield and New Haven Counties are part of the NY-NJ-CT PM2.5 nonattainment area.

Non-EGU Point Source Growth Factors 

Non-EGU point source growth factors were developed for Connecticut using employment or fuel 

consumption projections, depending on the source category.59 Connecticut Department of Labor 2006-

2016 employment forecasts by industry sector were provided for use as growth factors for non-fuel 

burning sources (such as manufacturing operations). MARAMA’s contractor extrapolated the 

employment forecasts through 2025 to develop emission estimates for these sources. Manufacturing 

employment projections for Connecticut are projected to decline by about 7% during the period, although 

declines are not as severe as those projected for other MANE-VU states. 

Annual Energy Outlook (AEO) fuel use projections published in 2010 by the U.S. Energy Information 

Administration were used to develop growth factors for fuel consuming sources.60 AEO provides 

regional fuel-use forecasts for various fuel types (e.g., coal, residual oil, distillate oil, natural gas) by end 

                                                           

59 See Section 3.1.1 and 2.3.1 of Appendix B for more detailed discussions of non-EGU growth factors. 

60 The 2011 update to the annual AEO forecasts was published midway through the inventory development process. 

MARAMA compared AEO2010 and AEO2011 projections, concluding that only one sector, industrial natural gas 

usage, was significantly different. Connecticut’s future year inventories were then changed to reflect the AEO2011 

forecast for that sector, with growth for all others non-EGU sectors remaining tied to the AEO2010 forecast. 
40 

uses (e.g., residential, commercial, industrial, transportation, and electric power). New England region 

forecasts were applied to Connecticut fuel burning sources. 

The AEO forecasts show declining trends for many fuel consumption sectors, especially industrial, 

residential, and commercial distillate fuel oil use. In order to be conservative in future emission 

estimates, Connecticut and several other states decided to apply a no-growth assumption (growth factor = 

1.0) for any non-EGU point source sector with a negative growth projection based on AEO forecasts. 

Such an approach could also help justify the creation of additional CERCs for facilities that might shut 

down during the maintenance period. 

Non-EGU Point Source Control Factors 

MARAMA’s contractor examined adopted federal and regional control strategies to determine those that 

would result in post-2007 emission reductions of PM2.5 or PM2.5 precursors from non-EGU point 

sources.61 Two federal toxics-related maximum achievable control technology (MACT) standards were 

identified that affect Connecticut sources, one for reciprocating internal combustion engines (RICE) and 

the other for industrial/commercial/institutional (ICI) boilers and process heaters. The contractor 

examined EPA guidance and documentation to determine that the RICE MACT will provide NOx or 

PM2.5 emission reductions and the ICI/process heater MACT will provide PM2.5 emission reductions from 

several non-EGU source classifications during the maintenance period. 

EGU Point Source Growth and Control Factors62

The 2007 EGU emissions were grown to future years based on AEO2011 electricity generation 

projections that delineated by market region and fuel type. The 2007 emissions were extracted for those 

units flagged as EGUs in the MANE-VU 2007 inventory. The appropriate AEO2011 growth factor was 

applied to the 2007 emissions to calculate a “growth only” emission value for 2017 and 2025. The 

following key assumptions were made because these inventories are not intended to be used for SIPquality photochemical modeling: 

• Any growth beyond unit capacity or permit limits was not limited (e.g., fuel consumption was 

allowed to grow beyond a unit’s physical capacity or permit limit); 

• Generation from any new units that may come on line and operate prior to 2025 but did not exist 

in 2007 is not explicitly included, but instead is assumed to be implicitly accounted for in the 

AEO2011 growth forecasts; 

• Similarly, generation from specific units that have or may shut down after 2007 is not explicitly 

accounted for, but instead, is assumed to be implicitly accounted for in the AEO2011 growth 

forecasts. 

• States indicated where post-2007 controls were to be applied on a unit-by-unit basis. The control 

factors were applied to the grown emissions to calculate a “growth and control” emission value 

for 2025. 

                                                           

61 See Section 3.3.2 of Appendix B for a discussion and references related to the identification of appropriate nonEGU control factors. 

62 See Sections 3.4.1 and 3.4.2 of Appendix B for a more complete description of EGU growth and control factors. 
41 

5.1.5 Area Source Inventory Procedures 

Area sources are relatively small, but often numerous, sources of air pollutants spread over a wide 

geographical area. They include sources that individually are insignificant, but in the aggregate may 

comprise significant emissions. Examples include emissions from home heating systems, small industrial 

or commercial operations that are not permitted as point sources, and road dust re-entrainment. There are 

356 individual area source categories in the MANE-VU inventory, categorized by a 10-digit SCC. 

 

The EPA regularly develops emission estimation methodologies and estimates for the National Emission 

Inventory (NEI). The NEI is developed on a three-year cycle, and inventories are available for 2002, 

2005, and 2008. CT DEEP initially instructed MARAMA to use EPA’s 2008 NEI63 emission values for 

all area source categories for the attainment year inventory. As described below, during the quality 

assurance effort, a number of categories were either discovered to be missing from the 2008 NEI, or used 

incorrect emission factor assumptions for Connecticut, so substitutions were made from either the 2005 

NEI64 or from CT DEEP’s draft 2005 periodic emission inventory65 (PEI). For residential wood 

combustion (RWC), MARAMA’s contractor ran EPA’s RWC tool with updated 2007 data to produce 

emission estimates. EPA’s 2011-updated methodology for developing emission factors for re-entrained 

particulate matter from vehicles traveling over a paved surface was also used. 

A full description of the area source development process is provided in the MANE-VU inventory 

documentation included as Appendix A (Section 4) and Appendix B (Sections 3 and 4). Note that Exhibit 

4.3 of Appendix A provides a tabular summary of data sources used for each state, including Connecticut, 

for each area source category. A summarized description of the area source inventory procedures is 

provided below, highlighting aspects unique to Connecticut for pollutants impacting the PM2.5 

redesignation effort. 

Quality Assurance

The area source inventory underwent a multi-step iterative review process to ensure data quality.66 The 

review process included: 

• Checks for missing categories, double counting, outliers and incorrect emission factors; 

• Comparisons between the 2007 and previously developed 2002 MANE-VU inventories to 

identify/verify/correct any facilities included in only one of those inventories; 

• For facilities included in both inventories, large emission changes between 2002 and 2007 were 

examined for reasonableness, with corrections made if warranted; 

• Source files were made available for stakeholder review, with requested changes evaluated for 

possible revisions. 

The quality assurance process resulted in additions, revisions and corrections to emission estimates for 

several area source categories in Connecticut, which were initially based solely on EPA’s 2008 NEI. The 

review process identified several area source categories that were not included in the 2008NEI. Missing 

                                                           

63 See http://www.epa.gov/ttnchie1/net/2008inventory.html. 64 See http://www.epa.gov/ttnchie1/net/2005inventory.html. 65 See Appendix F for excerpts from Connecticut’s draft 2005 PEI for selected area source categories. 66 See Section 2.1 through 2.7 of Appendix A for a full description of point source quality assurance procedures. 
42 

PM2.5-related categories included industrial fuel burning sources, commercial/institutional fuel burning 

sources, miscellaneous area source other-combustion (SCC 2810), industrial process mining/quarrying 

(SCC 2325), and miscellaneous area source crop agricultural crop production (SCC 2801). These missing 

categories were filled in with emission estimates from EPA’s 2005 NEI-v2. 

More detailed review discovered that EPA’s fuel burning estimates assumed a 2.25% sulfur level for 

residual fuel oil compared to a Connecticut regulatory maximum of 1.0% sulfur. In addition, CT DEEP 

could not verify whether EPA’s 2005 NEI-v2 adjusted its area source estimates to avoid double counting 

of point sources. CT DEEP addressed these issues by providing further updates to 2007 emission 

estimates for non-wood fuel combustion for the residential, commercial/institutional and industrial source 

categories. CT DEEP decided to use emission estimates from its draft-2005 PEI for the non-wood fuel 

combustion portions of the cited categories. The draft-2005 PEI includes only CO, VOC and NOx

emissions, so fuel use values were multiplied by appropriate EPA emission factors obtained from the 

2008 NEI to calculate estimates of annual SO2 and PM2.5 emissions. CT DEEP’s PEI also combined 

kerosene fuel use with distillate fuel use for the residential, commercial/institutional, and industrial 

sectors. Therefore, the 2007 MANE-VU inventory was modified by setting emissions for kerosene 

combustion SCCs to zero to avoid double counting of emissions. 

CT DEEP’s review of 2008 NEI emission estimates from land clearing debris activities also resulted in 

changes to the 2007 MANE-VU inventory. The methodology used for the 2008 NEI assumes all land 

clearing debris in rural counties is open burned, with no burning of debris in urban counties. This 

assumption greatly overestimates the mass of land clearing debris occurring in Connecticut, which is very 

limited. As a result, the 2005 NEI emission estimates were used instead because they are similar to 

estimates previously calculated by CT DEEP based on issued open burning permits. 

PM Transport Fractions 

Grid air quality models have consistently overestimated fugitive dust impacts when compared to ambient 

samples, indicating the importance of accounting for near-source removal mechanisms such as vegetation 

and other surface features. To address this issue, EPA developed a methodology to reduce fugitive dust 

emissions for use in grid modeling analyses.67 The MANE-VU 2007 and future year inventories apply 

the EPA defined county-level standard transport fractions and SCC assignments from EPA’s CHIEF 

website to adjust PM25-PRI emissions for specific fugitive dust categories such as paved and unpaved 

roads, construction activities and agricultural activities. Transport fractions in Connecticut’s two PM2.5 

nonattainment counties (Fairfield & New Haven) areas are both about 0.44, midway in the range of 0.14 

to 0.80 used for other nonattainment counties in the MANE-VU region. 

Area Source Growth Factors 

Growth factors were applied to the 2007 MANE-VU area source inventory to account for anticipated 

changes in fuel use, population and economic activity68 during the maintenance period. For Connecticut, 

growth factors were developed using six sets of data: 

• Annual Energy Outlook (AEO) New England region fuel consumption forecasts; 

• County-level population projections; 

                                                           

67 See the EPA CHIEF website at: http://www.epa.gov/ttnchie1/emch/dustfractions/. 68 See Section 2.3.1 of Appendix B for a more detailed discussion of area source growth factors. 
43 

• State-level employment projections; 

• County-level vehicle miles traveled (VMT) projections; and 

• EPA projections for residential wood combustion. 

As described earlier for the non-EGU sector, AEO fuel projections published in 2010 (AEO2010) were 

used for all fuel burning area source sectors, except for industrial natural gas combustion, which was 

updated to use AEO2011 projections. Industrial natural gas usage was the only sector showing a 

significant difference in future projections between the AEO2010 and AEO2011 forecasts. 

CT DEEP provided MARAMA’s contractor with county-level population projections developed in March 

2007 by the Connecticut Data Center at the University of Connecticut. Projected population increases 

between 2007 and 2025 are 6.7% for Fairfield County and 5.1% for New Haven County. These 

population-based growth factors were used for consumer-related area source sectors such as residential 

fuel combustion. 

The state-level employment projections previously described in Section 5.1.4 were also applied to 

manufacturing-related area source sectors. 

The Connecticut Department of Transportation (CTDOT) supplied VMT growth estimates that were used 

to project future year emission for re-entrained road dust from paved roads. Total VMT growth of 13.3% 

and 17.9% between 2007 and 2025 were used for Fairfield and New Haven Counties, respectively. 

For several area source categories, it seems reasonable that emissions would not change from the 2007 

values. No growth was applied to the 2007 emissions for PM2.5-related area source categories such as 

open burning and unpaved road dust.

For residential wood combustion (RWC), the MANE-VU inventories are based on emission projection 

parameters made available by EPA. EPA’s projected RWC emissions are based on the expected increase 

in the number of lower-emitting woodstoves. As newer, cleaner woodstoves replace older, more 

polluting stoves, there will be an overall reduction of emissions from this category. The approach used by 

EPA was developed as part of a modeling exercise to estimate the expected benefits of the woodstove 

change-out program. This methodology is based on activity, not pollutant. Growth and control are 

accounted for in a single factor for each residential wood SCC (certain SCCs represent controlled 

equipment, while others represent uncontrolled equipment). Control factors are indirectly incorporated 

based on which stove is used. 

Area Source Control Factors

MARAMA’s contractor examined adopted federal and regional control strategies to identify any that 

would result in post-2007 emission reductions of PM2.5 or PM2.5 precursors from area source categories.69 

As part of this process, EPA made available its 2020 emissions projections associated with its 2005-based 

v4 modeling platform. EPA’s modeling accounted for federal control strategies for four area source 

categories, only one of which was identified as reducing emissions of PM2.5 or PM2.5 precursors, the 

                                                           

69 See Section 2.3.2 of Appendix B for a discussion and references related to the identification of appropriate area 

source control factors. 
44 

replacement of retired woodstoves installed before promulgation of the new source performance standard 

(NSPS). As mentioned above, MARAMA’s contractor applied EPA’s latest RWC methodology70, which 

uses a combination growth and control factor and is based on activity and not pollutant. The growth and 

control are accounted for in a single factor for specific SCCs that account for the turnover from pre-NSPS 

to post-NSPS woodstoves. 

One post-2007 MACT standard was also incorporated into the MANE-VU future year area source 

inventories, EPA’s 2010 rule promulgated for reciprocating internal combustion engines (RICE). EPA 

made available estimates of the percent reductions in PM2.5 and NOx emissions attributable to the RICE 

MACT rule in 2012 and 2014. 

5.1.6 Non-Road Source Inventory Procedures 

Non-road sources include internal combustion engines used to propel marine vessels, airplanes, and 

locomotives, or to operate equipment such as forklifts, lawn and garden equipment, portable generators, 

etc. For activities other than marine vessels, airplanes, and railroad locomotives (MAR), the inventory 

was developed using the most current version of EPA’s NONROAD model as embedded in the National 

Mobile Inventory Model (NMIM). Because the NONROAD model does not include emissions from 

MAR sources, these emissions were estimated based on data and methodologies used in recent EPA 

regulatory impact analyses. The procedures used to run the NMIM/NONROAD platform and to 

determine emissions from MAR sources are discussed below. 

5.1.6.1 NMIM/NONROAD Modeling Methodology 

NMIM was developed by EPA to estimate county-level emissions for certain types of non-road 

equipment. NMIM uses the current version the NONROAD model, which estimates emissions from 

equipment such as recreational marine vessels, recreational land-based vehicles, farm and construction 

machinery, lawn and garden equipment, aircraft ground support equipment (GSE) and rail maintenance 

equipment. The NMIM national county database contains monthly input data to reflect county specific 

fuel parameters and temperatures. Most of the work associated with executing NMIM involved updating 

the NMIM county database with state-specific information. For this analysis, MARAMA’s contractor 

used the NMIM2008 software (version NMIM20090504), the NMIM County Database (version 

NCD20090531), and NONROAD2008a (July 2009 version) as a starting point. Changes were made to 

the NCD20090531 based on state review.71

Connecticut Changes to the NMIM National County Database and Other Inputs

MANE-VU States, including Connecticut, reviewed the NCD20090531 version of the National County 

Database (NCD) to determine if any parameters should be corrected or updated. CT DEEP requested 

changes to several fuel-related characteristics to make them consistent with reformulated gasoline (RFG) 

                                                           

70 See Section 2.3.1.6 of Appendix B for a more complete description of EPA’s methodology for projecting RWC 

emissions. 

71 See Section of 4 of Appendix A for a more complete description of NMIM/NONROAD modeling procedures. 
45 

sampling results reported by EPA for RVP, sulfur and ethanol oxygen weight percents in Connecticut’s 

multiple RFG areas. 

Several NONROAD categories use housing unit or population data to allocate the emissions to the county 

level from state calculations. States identified some discrepancies in the housing and population data 

contained in the NONROAD model and requested that MARAMA’s contractor update the allocation files 

for those categories. Consequently, the contractor obtained and applied 1 and 2 unit housing information 

and updated Census Bureau 2007 population estimates for each state, including Connecticut. The revised 

housing unit data affected the allocation of residential lawn and garden equipment. Revised population 

files applied to railroad maintenance equipment and AC/refrigeration equipment. 

Removal of Airport Ground Support Equipment Emissions 

The NMIM/NONROAD model includes emissions from airport ground support equipment. Emissions 

from airport ground support equipment can also be calculated using the Federal Aviation 

Administration’s (FAA) Emissions and Dispersion Modeling System (EDMS). MARAMA’s 

correspondence with EPA indicated that EPA considers the emissions calculated by EDMS to be better 

than those calculated by NONROAD. For this reason, all emissions calculated by NMIM/NONROAD 

for airport ground support equipment were removed from the 2007, 2017 and 2020 inventories and 

replaced with EDMS estimates, as described in Section 5.1.6.2. 

Future Year NMIM/NONROAD Growth and Control Information 

In estimating future year emissions, the NMIM/NONROAD model includes growth and scrappage rates 

for equipment in addition to a variety of control programs. It is not possible to separate out the future 

year emissions due to “growth only” or “control only” in a single run. That is, the model run provides a 

single future year estimate that is a “growth and control” scenario. The GROWTH packet of the 

NONROAD model cross-references each SCC to a growth indicator code. The indicator code is an 

arbitrary code that identifies an actual predicted value such as human population or employment that is 

used to estimate the future year equipment population. The GROWTH packet also defines the scrappage 

curves used to estimate the future year model year distribution.

The NMIM/NONROAD model accounts for all adopted EPA emission standards for non-road equipment. 

There are multiple standards that vary by equipment type, rated power, model year, and pollutant. Exhibit 

4.1 of Appendix C provides a tabular summary of the emission control programs accounted for in the 

NMIM/NONROAD model. 

Finally, as mentioned above, airport ground service emissions were removed from the future year 

NMIM/NONROAD runs and were replaced by estimates calculated by the FAA EDMS model. 

5.1.6.2 MAR Methodology 

This category of sources is collectively referred to as the MAR (marine, airports, and railroads) sector. It 

includes non-road engines associated with the following activities: 

• Marine Vessels: The Commercial Marine Vehicle (CMV) sector includes all boats and ships 

used either directly or indirectly in the conduct of commerce or military activity. The majority of 
46 

these vessels are powered by diesel engines that are fueled with either distillate or residual fuel oil 

blends. For the purpose of this inventory, it is assumed that Category 3 vessels primarily use 

residual blends, while Category 1 and 2 vessels typically used distillate fuels. 

• Airports: The aircraft sector includes all aircraft types used for public, private, and military 

purposes. This includes four types of aircraft: commercial, air taxis, general aviation and 

military. Ground support equipment (GSE) and auxiliary power units (APU) are also included. 

• Railroads: The railroad sector includes railroad locomotives powered by diesel-electric engines. 

Locomotives are divided into Class I line haul, Class II/III line haul, commuter/passenger and 

Class I yard. 

2007 Commercial Marine Vessel Inventory Development 

Along with several other MANE-VU states, Connecticut elected to use EPA’s 2008 NEI data for all 

commercial marine vessel categories. These estimates include emissions from CMV operation generally 

within 12 nautical miles of shore. The 2008 NEI data were used directly for 2007 (i.e., the 2007 

emissions were assumed to be equal to 2008). 

Future Year Commercial Marine Vessel Inventory Development 

For the purpose of emission calculations, marine vessel engines are divided into three categories based on 

displacement (i.e. swept volume) per cylinder. Category 1 and Category 2 marine diesel engines typically 

range in size from about 500 to 8,000 kW (700 to 11,000 hp). These engines are used to provide 

propulsion power on many kinds of vessels including tugboats, pushboats, supply vessels, fishing vessels, 

and other commercial vessels in and around ports. They are also used as stand-alone generators for 

auxiliary electrical power on vessels. Category 3 marine diesel engines typically range in size from 2,500 

to 70,000 kW (3,000 to 100,000 hp). These are very large marine diesel engines used for propulsion 

power on ocean-going vessels such as container ships, oil tankers, bulk carriers, and cruise ships. 

The majority of marine vessels are powered by diesel engines that are fueled with either distillate or 

residual fuel oil blends. For the purpose of emission inventories, EPA has assumed that Category 3 

vessels primarily use residual blends, while Category 1 and 2 vessels typically use distillate fuels. EPA 

developed national emission inventories for Category 1 and 2 vessels and Category 3 vessels for calendar 

years 2002 through 2040 as part of its effort to develop emission standards for these vessels. The 

methodologies used to develop the emission projections (for both a baseline and controlled scenario) are 

documented in three EPA regulatory impact assessments (RIA).72 MARAMA’s contractor used EPA data 

and methodologies from these RIAs to develop separate growth and control factors for Category 1 and 2 

vessels (diesel) and Category 3 vessels (residual). 

2007 Airport Inventory Development 

Connecticut aircraft emissions in the 2007 MANE-VU inventory are available on a county-by-county 

basis for six types of aircraft operations: 

• Air carrier operations represent landings and take-offs (LTOs) of commercial aircraft with seating 

capacity of more than 60 seats; 

                                                           

72 See Section 5.3.1 of Appendix B for a full description of the EPA methodology used for CMV emission 

projections and the associated EPA references. 
47 

• Commuter/air taxi operations are one category. Commuter operations include LTOs by aircraft 

with 60 or fewer seats that transport regional passengers on scheduled commercial flights. Air 

taxi operations include LTOs by aircraft with 60 or fewer seats conducted on non-scheduled or 

for-hire flights; 

• General aviation represents all civil aviation LTOs not classified as commercial; 

• Military operations represent LTOs by military aircraft; 

• Ground Support Equipment (GSE) typically includes aircraft refueling and baggage handling 

vehicles and equipment, aircraft towing vehicles, and passenger buses; 

• Auxiliary power units (APUs) provide power to start the main engines and run the heating, 

cooling, and ventilation systems prior to starting the main engines. 

CT DEEP calculated 2007 airport-related emissions based on the 2008 NEI for airport ground support 

equipment and auxiliary power units, detailed 2005 aircraft activity data from Connecticut-specific 

survey data and emission factors obtained from EDMS 5.1, augmented by PM emission factors from EPA 

2008 documentation for non-International Civil Aviation Organization (ICAO) certified engines. Growth 

factors were developed from the 2009 Terminal Air Forecast (TAF) database. No growth was assumed if 

a TAF-based growth factor was not available. Results were provided to MARAMA for inclusion in the 

2007 MANE-VU inventory. See Appendix G for further detail. 

Future Year Airport Inventory Development 

CT DEEP provided MARAMA with state-specific growth factors through 2025 by SCC and county. 

These growth factors closely followed the approach used and described in the MARAMA effort; 

however, the airport specific activity was grown based on the Terminal Air Forecasts for each airport 

where available (or no growth when not available) rather than applying a composite average growth 

factor for a county. See Appendix G for further detail. 

MARAMA’s contractor reviewed NOx aircraft engine emissions standards adopted by EPA in November 

2005. The standards are equivalent to the NOx emission standards (adopted in 1999 for implementation 

beginning in 2004) of the United Nations International Civil Aviation Organization (ICAO), and will 

bring the US aircraft standards into alignment with the international standards. The standards apply to 

new aircraft engines used on commercial aircraft including small regional jets, single-aisle and twin-aisle 

aircraft, and 747s and larger aircraft. The standards also apply to general aviation and military aircraft, 

which sometimes use commercial engines. For example, small regional jet engines are used in executive 

general aviation aircraft, and larger commercial aircraft engines may be used in military transport aircraft. 

Nearly all previously certified or in-production engine models currently meet or perform better than the 

standards EPA adopted in the November 2005 rule. In addition, manufacturers have already been 

developing improved technology in response to the ICAO standards. This rule is expected to reduce NOx

emissions by approximately 2 percent in 2015 and 3 percent in 2020. Because of the relatively small 

amount of NOx reductions, the MANE-VU future year aircraft emission projections do not account for 

this control program. 

2007 Railroad Inventory Development 

Railroad locomotive engine emissions in the 2007 MANE-VU inventory are classified into the following 

categories: 
48 

• Class I line haul locomotives are operated by large freight railroad companies and are used to 

power freight train operations over long distances (SCC 22-85-002-006); 

• Class II/III line haul locomotives are operated by smaller freight railroad companies and are used 

to power freight train operations over long distances (SCC 22-85-002-007); 

• Inter-city passenger train locomotives are operated primarily by Amtrak to provide inter-city 

passenger transport (SCC 22-85-002-008); 

• Independent commuter rail systems operate locomotives that provide passenger transport within a 

metropolitan area (SCC 22-85-002-009); and 

• Yard/switch locomotives are used in freight yards to assemble and disassemble trains, or for short 

hauls of trains that are made up of only a few cars (SCC 22-85-002-010). 

Along with many other MANE-VU states, Connecticut participated in the Eastern Regional Technical 

Advisory Committee (ERTAC) inventory effort for railroad locomotives and rail yards73 as the starting 

point for developing the 2007 railroad emissions inventory. The ERTAC rail inventory included only 

larger categories of locomotive emissions, such as large Class I line-haul and Class I rail yard switchers. 

This focus did not fit Connecticut’s railroad profile of predominantly line haul commuter (e.g. Shoreline 

East) and passenger (e.g., AMTRAK) activity, with Class II/III short line and regional railroads and a 

Class I railroad isolated from the Class I hub by Class II and III owned rail and a substandard bridge 

associated with an inconvenient pathway thru New York. Consequently, the ERTAC effort was not of 

direct use and CT DEEP calculated all the emissions needed for the 2007 railroad inventory. See 

Appendix H for further detail. 

Future Year Railroad Inventory Development 

In March 2008, EPA finalized a three-part program that will dramatically reduce emissions from diesel 

locomotives of all types -- line-haul, switch, and passenger rail. As part of this work, EPA developed a 

national emission inventory for calendar years 2002 through 2040. Emission projections methodologies 

for a baseline and controlled scenario were developed and documented.74 MARAMA’s contractor used 

the EPA methodology, updated with AEO2010 projections for passenger rail and freight rail energy use to 

develop MANE-VU future year inventories.

5.1.7 On-Road Mobile Source Inventory Procedures 

EPA’s recently released MOVES2010 (MOtor Vehicle Emission Simulator) is now the official model for 

estimating air pollution emissions from on-road mobile sources including buses, cars, trucks and 

motorcycles for SIP purposes75. MOVES2010 replaces MOBILE6.2, EPA’s previous mobile source 

model. MOVES input files are more detailed than the MOBILE6.2 input files. To assist in the transition 

to the new model, EPA developed software tools to convert certain MOBILE6.2 inputs for MOVES. 

                                                           

73 See Section 6.3 of Appendix A for more information on the ERTAC railroad inventory and associated ERTAC 

reference material. 

74 See Section 5.3.3.1 of Appendix B for a more complete discussion of how the projected railroad emissions were 

determined, as well as for associated EPA references. 

75 Emission estimates in this SIP revision were developed using MOVES2010a, EPA’s latest version at the time. EPA 

subsequently released a minor update, MOVES2010b in April2012. EPA documentation indicates that MOVES2010b does not 

significantly affect criteria pollutant emissions compared to previous versions of MOVES2010.
49 

These inputs were loaded into the MOVES County Data Manager (CDM), which together with LEV 

database files and MOVES run Specifications, were used to generate MySQL database output files 

generated by the MOVES Model. Post processing was accomplished using SQL in either MySQL or MS 

Access. 

States involved in the regional MARAMA inventory effort were offered the option of having NESCAUM 

perform the MOVES modeling using input data provided by and/or reviewed by the states. CT DEEP 

initially selected this option and provided the requested 2007 and 2025 inputs to MARAMA/NESCAUM 

in 2010 from data available at that time. By early 2012, CT DEEP was able to assemble updated MOVES 

data sets for several required parameters and elected to perform its own MOVES runs (using the 

inventory mode) with the updated data for 2009, 2017 and 2025. Connecticut’s MOVES input data sets 

are summarized in Tables 5.2 through 5.4, with more detailed documentation provided in Appendix I. 

Table 5.2 describes the selections made when creating the MOVES 2010a run specifications. Table 5.3 

summarizes the CDM inputs loaded into the MOVES model. Table 5.4 lists references cited in the 

previous two tables. 

Connecticut decided to include 2009 MOVES on-road emission estimates in the PM2.5 attainment year 

inventory, rather than developing updated 2007 emission estimates. This was done for several reasons. 

First, EPA had previously approved 2009 transportation conformity motor vehicle emission budgets 

(MVEB) for Connecticut that were determined using MOBILE6.2; the 2009 MOVES estimates were 

initially intended to replace those budgets using EPA’s state-of-the art model (see Section 5.1.9 for an 

explanation of why 2009 MVEBs are no longer necessary). Second, since on-road emissions are steadily 

decreasing due to fleet turnover to lower emitting vehicles, 2009 on-road emissions are lower than 2007 

estimates (see the next paragraph for a comparison of 2007 and 2009 on-road emissions). Use of the 

lower 2009 on-road emission estimates for 2007 ensures that the total attainment year inventory across all 

source sectors will be more conservative (i.e., lower) than if 2007 on-road emissions were used. Since 

emissions through the end of the maintenance period must be no higher than the attainment year 

inventory, this approach provides additional assurance that NAAQS compliance will continue through the 

maintenance period. 
50 

Table 5.2 MOVES Run Specifications

Scale 

Description MOVES Scale input page (panel) allows the selection of the Domain/Scale and 

Calculation Type for the run specification. 

Data Source EPA recommends the use of the county scale for SIP analyses [R3]. The Inventory 

Calculation type was used to integrate input calculations for a direct result for quick 

and reliable calculation of emissions. 

Time Spans 

Description MOVES Time Spans panel allows the selection of Time Aggregation Level (inputs), 

Years, Months, Type of Days and Hours. [R3] 

Data Source For SIP and regional conformity analysis, hour should be selected for Time 

Aggregation Level. Because emissions of criteria pollutants are dependent on 

ambient temperature, diurnal, daily, and monthly variations in temperature can have 

large impacts on emission results. [R3] 

MOVES can model calendar years 1990 and 1999-2050, inclusive. The County scale 

in MOVES allows only a single calendar year in a run specification [R3]. For the 

PM2.5 redesignation effort, 2009, 2017 and 2025 were selected. A separate run and 

run specification was needed for each year and for each county. 

To obtain an annual estimation of direct PM2.5 emissions, SO2 and NOx, all twelve 

months, week and weekday were selected under the Day submenu and all hours (24 

hours per day) were selected for the time span applicable to the MOVES run. 

Geographic Bounds 

Description MOVES requires the selection of a single county for each year when County is 

selected for the Domain/Scale. [R1] 

Data Source The Connecticut counties associated with the PM2.5 redesignation effort are Fairfield 

and New Haven. Individual run specifications and detailed county data manager 

inputs were provided for each count and each year modeled. County Data Manager 

inputs are further described in the table for MOVES Inputs below. 

Vehicles/Equipment - On Road Vehicles 

Description Allows the selection of Fuels and Source Use Types (types of vehicles) 

combinations. 

Data Source For SIP and regional conformity analyses, the appropriate fuel and vehicle type 

combinations in the On Road Vehicle Equipment panel must be selected to reflect 

the full range of vehicles that will operate in the county for the year selected. [R3] 

Liquefied Petroleum Gas (LPG) and the Placeholder Fuel Type were not included in 

the selection of fuels/vehicle combination included in Connecticut’s run 

specification. EPA discourages the inclusion of the placeholder fuel. LPG was not 

included due to warnings produced at the time of the creation of the RunSpec, which 

was judged not worth investigating due to zero or extremely low vehicle LPG vehicle 

populations and VMT. 
51 

Road Type

Description There are five available road types: Off-network, Rural Restricted Access, Rural 

Unrestricted Access, Urban Restricted Access, Urban Unrestricted Access. 

Data Source All five road type categories were selected to calculate a total annual emission 

estimate for direct PM2.5 pollutants. 

Pollutants and Processes 

Description Pollutants, precursors and the processes that can generate them can be selected in this 

input page [R3] 

Data Source The PM2.5 redesignation effort requires estimates for direct PM2.5, NOx and SO2. 

Manage Input Data Sets (MIDS) 

Description This panel allows users to create and use alternate data tables that are not part of the 

County Data Manager (CDM) inputs and that will be used in place of data from the 

MOVES default database [R3]. 

Data Source Connecticut was required to use the MIDS option to adjust emission factors 

associated with early adoption of the Low Emission Vehicle Standards. Connecticut 

adopted California Low Emission Vehicle (LEV) II standards in 2008 and also 

adopted early implementation of National Low Emission Vehicle (NLEV) standards 

for the 1999 and 2000 model years. Connecticut used the EPA’s early LEV database 

and a database created following EPA directions for creating a CALEV database to 

properly model Connecticut emissions. The early adoption of National LEV (early 

LEV) and a database for CA LEV II were included in MIDS to adjust emissions for 

all years considered in this analysis [R5]. 

Output - General Output 

Description This panel includes general information about the output. 

Data Source The name of the output database, the units (mass in U. S. Tons, energy in Joules and 

distance in Miles) for the output and the Activity Output requested. For activity, 

Distance Traveled and Population were selected to provide a quick check for these 

inputs. 

Output - Output Emissions 

Description In this subpanel several options can be selected. These options tell the model the 

level of aggregation of the outputs and how the results should be aggregated. 

Data Source Since the PM 2.5 redesignation relies on an annual analysis, aggregation of the results 

at a monthly level greatly simplifies post processing requirements. This makes post 

processing easy and reduces the possibility of introducing errors. Results were 

segregated by Fuel Type, Emissions Processes Road Type and Source Use Type to 

provide the capability to view/review results in different ways. 

Table 5.2 MOVES Run Specifications (continued) 
52 

Table 5.3 MOVES County Data Manager (CDM) 

Age Distribution

Description Vehicle age is used to determine the vintage of vehicle emission control technologies 

and vehicle deterioration. Fleets with a higher percentage of older vehicles have 

higher emissions than fleets with newer vehicles. MOVES covers a 31-year range of 

vehicle ages, with vehicles 30 years and older grouped together [R3]. 

Data Source The 2011 registration data set was fully evaluated, assigned a model year and 

assigned a MOBILE6.2 16-vehicle type classification based on CT DMV registration 

data. A MOBILE6.2 age distribution and a MOVES age distribution were developed 

directly from the results of the DMV data analysis. The EPA’s default diesel sales 

algorithm was used to convert the MOBILE6.2 16-vehicle type classifications to 

MOBILE6.2 28-vehicle type classifications. Table A.1 of the MOVES Technical 

Guidance [R3] was used to map the MOBILE6.2 28-vehicle type classification 

populations to MOVES source type populations. 

Average Speed Distribution

Description Average speed is used to calculate vehicle run times and to determine the emission 

factor of the vehicles. Higher speeds for a given VMT reduces run time and the total 

time for running emissions, however higher speeds are typically associated with 

higher emission factors. Average speed data specific to vehicle type 

(sourceTypeID), road type (roadTypeID), and time of day/type of day (hourdayID) 

provides the data necessary for MOVES to calculate emissions. MOVES defines 16 

"speed bins" which describe the average driving speed on a road type or link. 

MOVES uses a time-based distribution, whereas MOBILE6.2 used a VMT-based 

speed distribution. 

Data Source Connecticut used EPA Average Speed converters to produce MOVES inputs from 

MOBILE6.2 Speed-VMT files. 

Fuel 

Description Fuels inputs include both fuel formulation and fuel supply. Fuel Formulation 

specifies the components of the fuels considered. Fuel Supply indicates the fuel 

formulation’s fraction of the volume consumed in the area (i.e. market share) [R3]. 

Data Source MOVES default fuels inputs were used for all fuels except diesel and gasoline. 

Sulfur is the key parameter for diesel fuel. Diesel values were set at values specified 

in EPA guidance (i.e. 43 ppm in 2009 and 43 ppm after 2010). [R4] Connecticut 

specific reformulated gasoline data were used to establish gasoline parameters. 

Meteorology 

Description MOVES meteorological inputs consist of temperature and humidity data for 

months, zones (counties) and hours included in the MOVES run 

specification. Temperature and to a lesser extent humidity affect emission 

estimates; thus, assumptions used for regional conformity analyses must be 

consistent with those used to establish the emissions budget in the SIP as 

required in the transportation conformity rule, 40 CFR §93.122(a)(6) [R3]. 

Data Source MOVES meteorological inputs used the NMIM National County Database 

(version NCD20090531) for 2007, 2017 and 2025 to maintain consistency. 

[R5] 
53 

Road Type Distribution

Description Road Type Distribution provides VMT fraction data relating to the vehicle 

miles traveled by road type (roadTypeVMTFraction) for the county being 

modeled. This data is entered as a distribution across road types 

(roadTypeID), where only road types selected by the user in the run 

specification are included in the distribution. The distribution must sum to one 

for each source type. 

Data Source Road Type Distribution was calculated for each Connecticut county using a 

preprocessor to produce a MOVES input table based on localization of 

adjusted default VMT mixes and Connecticut specific 2010 HPMS vehicle 

counts. This preprocessor table output county VMT estimates, MOBILE6.2 

age distribution from 2011 DMV registration data, Connecticut 2009 VMT by 

hour observations and ramp fractions were input into EPA’s 16 vehicle type / 

12 road type level VMT converter to obtain road type distribution outputs. 

Source Type Population

Description Source type (vehicle type) population is used by MOVES to calculate start 

and evaporative emissions. Because vehicle population directly determines 

start and evaporative emission, local data for this input must be developed. 

Data Source The MOVES model categorizes vehicles into 13 source types, which are 

subsets of 6 MOVES HPMS vehicle types. 2011 Connecticut DMV 

Registration data was analyzed to develop population data for Mobile 6.2 16-

vehicle type classifications. The EPA’s default diesel sales algorithm was 

used to convert the MOBILE6.2 16-vehicle type classifications to MOBILE6.2 

28-vehicle type classifications. Table A.1 of the MOVES Technical Guidance 

[R3] was used to map the MOBILE6.2 28-vehicle type classification 

populations to MOVES source type populations. Connecticut Specific 2009 

HPMS vehicle miles travelled (VMT) from MOVES input files were used to 

augment vehicle counts for Source Types within the HPMS 50 and 60 type 

obtained directly from the 2011 registration data. Growth factors based on 

Connecticut specific DOT estimates for each of the 6 MOVES HPMS vehicle 

type VMT for each Connecticut county were applied to each of the 

associated MOVES Source Types to develop Source Type Populations for 

2017 and 2025. [R8] 

Ramp Fraction

Description Ramp Fraction is the fraction of ramp driving time on selected road types. 

Only limited access road types (freeways and interstates) may have their 

ramp fractions modified. [R2] MOVES converters improperly indicate ramp 

VMT fraction. [R2, R9] 

Data Source Ramp VHT was estimated by dividing Ramp VMT by the average speed for 

the appropriate road types set forth in MOBILE6.2 guidance. 

Table 5.3 MOVES County Data Manager (continued) 
54 

Vehicle Type VMT

Description As input, MOVES requires annual VMT by HPMS vehicle class but users can 

input average annual daily VMT as well as monthly and weekend day 

adjustment factors to create the annual VMT by HPMS class and appropriate 

monthly and daily adjustments needed by MOVES [R3]. 

Data Source Annual vehicle type VMT was calculated for each Connecticut county using a 

preprocessor to produce a MOVES input table based on localization of 

adjusted default VMT mixes and Connecticut specific 2010 HPMS vehicle 

counts. This preprocessor table output, county VMT estimates, MOBILE62 

age distribution from 2011 DMV registration data, Connecticut 2009 VMT by 

hour observations and ramp fractions were input into EPA’s 16 vehicle type / 

12 road type level VMT converter to obtain road type distribution outputs, 

hourVMTFraction, MOVES Source Type Age Distribution, and road type 

ramp fractions. The HPMSVTypeYear – daily VMT together with monthly 

adjustment factor based on seasonal VMT variations and EPA default 

weekend-day adjustment factor were input into the EPA Annual Average 

Weekday Vehicles Miles Travelled converter (aadvmtcalculator_hpms.xls) to 

generate the HPMSVTypeYear (annual), monthVMTFraction, and 

dayVMTFraction tables from Annual Average Weekday Vehicles Miles 

Travelled (AADVMT) and monthly/weekend-day adjustment factors [R9] 

Inspection and Maintenance (I/M) 

Description The MOVES I/M input is used to calculate the emission benefit of the I/M 

program. A unique set of I/M inputs is needed for each calendar year and 

county modeled. The Connecticut vehicle I/M program is an important part of 

the strategy to ensure that Connecticut is positioned to attain the National 

Ambient Air Quality Standard for Ozone. [R6]. 

Data Source Connecticut I/M inputs were developed in accordance with the MOVES SIP 

and conformity Technical Guidance [R3]. I/M program inspection frequency, 

inspection program, process, pollutant and vehicle regulatory class / MOVES 

source type applicability mappings were determined based on EPA technical 

guidance. Compliance factor was calculated based on the light duty vehicle 

fleet only and the following I/M data: 2009 I/M inputs were based on I/M 

compliance and waiver rate observations. Future year I/M inputs were based 

on I/M SIP compliance & waiver rate commitments. [R6,R7] All EPA MOVES 

default I/M inputs were deactivated by setting the “useIMyn” field to “N”. 

Table 5.3 MOVES County Data Manager (continued)
55 

Table 5.4 References Cited in Table 5.2 and 5.3 

Reference 

Number Reference 

[R1] 

EPA. Final Rule to Add PM 2.5 Precursors to the Transportation Conformity Rule. 

EPA-420-F-05-005. May 2005. 

http://www.epa.gov/otaq/stateresources/transconf/regs/420f05005.pdf

[R2] 

EPA. Motor Vehicle Emission Simulator (MOVES) User Guide for 

MOVES2010a. EPA-420-B-10-036. December 2009. 

http://www.epa.gov/otaq/models/moves/MOVES2010a/420b10036.pdf

[R3] 

EPA. Technical Guidance on the Use of MOVES2010 for Emission Inventory 

Preparation in State Implementation Plans and Transportation Conformity. EPA420-B-10-023. April 2010. 

http://www.epa.gov/otaq/models/moves/420b10023.pdf

[R4] 

EPA. Technical Guidance on the Use of MOBILE6.2 for Emission Inventory 

Preparation. EPA-420-R-04-013. August 2004. 

http://www.epa.gov/otaq/models/mobile6/420r04013.pdf

[R5] NESCAUM. Development of MANE-VU Onroad Mobile Source Emissions for 

2007 and 2020 using MOVES. December 2011. 

[R6] 

De la Torre Klausmeir Consulting. 2007 Connecticut’s Inspection/Maintenance 

Program Evaluation. June 2008. 

http://www.ct.gov/dep/lib/dep/air/vehicle_emissions/2007imreport&appendicesfinal.pdf

[R7] 

Connecticut Department of Environmental Protection. Revision to the 

Connecticut’s State Implementation Plan. Enhanced Motor Vehicle Inspection and 

Maintenance Program. December, 2007. 

http://www.ct.gov/dep/lib/dep/air/regulations/proposed_and_reports/final2007_im_sip_revision.pdf

[R8]

EPA. Fleet Characterization Data for MOBILE6: Development and Use of Age 

Distributions, Average Annual Mileage Accumulation Rates, and Projected 

Vehicle Counts for Use in MOBILE6 (M6.FLT.007). EPA-420-R-01-047. 

September 2001. http://www.epa.gov/oms/models/mobile6/r01047.pdf

[R9] EPA MOVES Converters. http://www.epa.gov/otaq/models/moves/tools.htm
56 

Although CT DEEP did not develop MOVES estimates of 2007 on-road emissions with updated 

Connecticut inputs, MARAMA’s inventory does include 2007 MOVES estimates for Connecticut’s 

portion of the NY-NJ-CT area using the previous vintage of Connecticut inputs. The 2009 CT DEEP 

runs include updates to input parameters such as the vehicle age distribution, which has become slightly 

older due to lower vehicle sales during the recent recession. The updated inputs were also used to 

develop the 2017 and 2025 conformity budgets. 

Table 5.5 compares MARAMA’s 2007 estimates to the 2009 estimates produced by CT DEEP. The 2009 

on-road emission estimates are lower than those developed for 2007, supporting CT DEEP’s decision to 

use 2009 estimates in the attainment year inventory. 

Table 5.5 Comparison of MOVES Emissions for 2007 and 2009 

MOVES On-Road Emission 

Estimates for Fairfield and 

New Haven Counties 

PM2.5 

(tons/year) 

NOx 

(tons/year) 

SO2 

(tons/year) 

2007 MARAMA 815 24,384 187 

2009 CT DEEP 794 23,391 176 

When these results are considered together with the significant emission reductions projected through 

2025 by CT DEEP’s MOVES runs (see Tables 5.6 through 5.8 of the TSD), it is clear that on-road 

emissions have been declining and will continue to decline throughout the maintenance period. 

5.1.8 Comparison of Attainment Year and Projected Future Year Emissions 

As described earlier, EPA’s maintenance plan guidance requires states to provide an emissions inventory 

representative of the level of emissions sufficient to attain the NAAQS. In addition, the maintenance plan 

should include a demonstration of continued compliance by showing that future emissions during the 

maintenance period will not exceed the level of emissions in the attainment inventory. The inventory 

procedures described above were applied to determine emission levels for 2007, the representative 

attainment year. Emissions during the maintenance period were estimated for both an interim year (2017) 

and the final year (2025) of the maintenance period to show continuing compliance. 

Table 5.6 summarizes estimated annual PM2.5 emissions in 200776, 2017 and 2025 by major source sector 

for the two Connecticut counties that are part of the NY-NJ-CT PM2.5 nonattainment area, as well totals 

for the both counties combined. Also listed are the changes (tons/year and percentage) between 2007 and 

2025. Tables 5.7 and 5.8 summarize the same information for NOx and SO2 emissions, respectively. 

Appendix D provides information to access MARAMA’s ftp site, which includes detailed breakdowns of 

emissions for all categories except for the on-road mobile source emission estimates. Further information 

for on-road mobile emissions is included in Section 5.1.7 and Appendix I. 

                                                           

76 As described in Section 5.1.7, Connecticut elected to combine on-road mobile source emission estimates for 2009 with 2007 

emission estimates for all other source categories when establishing the level of emissions that provides for attainment. Since onroad emissions are steadily decreasing due to fleet turnover to lower emitting vehicles, 2009 on-road estimates are lower than 

2007 estimates. Therefore, the total attainment year inventory is more conservative (i.e., lower) than if 2007 on-road emissions 

were used. Since emissions through the end of the maintenance period must be no higher than during the attainment year, this 

approach provides additional assurance that NAAQS compliance will continue through the maintenance period.
57 

Particulate Matter (PM25‐PRI)  V3.3 2007 2017 2025

2007 to

2025

2007 to

2025

Annual Annual Annual   Change Change  

State FIPS County SECTOR (tons) (tons) (tons) (tons) (Percent)

CT 09001 Fairfield AREA 1,991.5 1,892.3 1,827.5  ‐163.9  ‐8%

CT 09001 Fairfield NONROAD MAR 119.9 61.7 45.0  ‐74.8  ‐62%

CT 09001 Fairfield NONROAD NMIM 403.0 292.5 244.1  ‐158.9  ‐39%

CT 09001 Fairfield ONROAD MOVES 404.4 238.0 192.7  ‐211.7  ‐52%

CT 09001 Fairfield POINT EGU 283.5 79.4 131.5  ‐152.0  ‐54%

CT 09001 Fairfield POINT NONEGU 44.7 47.3 49.6 4.9 11%

      Fairfield Total    3,247.0 2,611.2 2,490.4 ‐756.5 ‐23%

CT 09009 New Haven AREA 1,900.3 1,804.9 1,746.3  ‐153.9  ‐8%

CT 09009 New Haven NONROAD MAR 168.5 73.0 51.6  ‐117.0  ‐69%

CT 09009 New Haven NONROAD NMIM 279.1 181.7 136.8  ‐142.3  ‐51%

CT 09009 New Haven ONROAD MOVES 389.6 229.4 186.2  ‐203.4  ‐52%

CT 09009 New Haven POINT EGU 88.1 84.4 83.8  ‐4.2  ‐5%

CT 09009 New Haven POINT NONEGU 40.4 44.5 46.6 6.2 15%

      New Haven Total 2,866.0 2,417.9 2,251.3 ‐614.7 ‐21%

     

Total CT

Portion of

NY‐NJ‐CT Area   

6,113.0 5,029.1 4,741.7 ‐1,371.2 ‐22%

Oxides of Nitrogen (NOx)  V3.3 2007 2017 2025

2007 to

2025

2007 to

2025

Annual Annual Annual   Change Change  

State FIPS County SECTOR (tons) (tons) (tons) (tons) (Percent)

CT 09001 Fairfield AREA 3,088.8 2,771.3 2,740.1  ‐348.7  ‐11%

CT 09001 Fairfield NONROAD MAR 3,034.2 1,957.5 1,345.4  ‐1,688.8  ‐56%

CT 09001 Fairfield NONROAD NMIM 4,648.1 2,615.8 2,057.3  ‐2,590.8  ‐56%

CT 09001 Fairfield ONROAD MOVES 11,888.9 5,414.1 3,573.2  ‐8,315.7  ‐70%

CT 09001 Fairfield POINT EGU 2,268.5 741.7 1,108.2  ‐1,160.3  ‐51%

CT 09001 Fairfield POINT NONEGU 1,875.4 2,224.0 2,543.5 668.1 36%

      Fairfield Total    26,804.0 15,724.4 13,367.8 ‐13,436.2 ‐50%

CT 09009 New Haven AREA 2,936.1 2,636.8 2,608.1  ‐328.0  ‐11%

CT 09009 New Haven NONROAD MAR 3,945.9 2,487.0 1,736.2  ‐2,209.7  ‐56%

CT 09009 New Haven NONROAD NMIM 3,688.1 2,076.6 1,603.9  ‐2,084.3  ‐57%

CT 09009 New Haven ONROAD MOVES 11,502.7 5,293.9 3,540.1  ‐7,962.6  ‐69%

CT 09009 New Haven POINT EGU 639.6 386.6 384.5  ‐255.0  ‐40%

CT 09009 New Haven POINT NONEGU 822.7 896.0 951.6 128.9 16%

      New Haven Total    23,535.1 13,776.9 10,824.4 ‐12,710.7 ‐54%

     

Total CT

Portion of

NY‐NJ‐CT Area   

50,339.1 29,501.3 24,192.2 ‐26,146.9 ‐52%

Table 5.6 Connecticut PM2.5 Emissions Inventory Projections 2007-2025 

Table 5.7 Connecticut NOx Emissions Inventory Projections 2007- 2025 
58 

Sulfur Dioxide (SO2)  V3.3 2007 2017 2025

2007 to

2025

2007 to

2025

Annual Annual Annual   Change Change  

State FIPS County SECTOR (tons) (tons) (tons) (tons) (Percent)

CT 09001 Fairfield AREA 3,917.3 3,157.5 2,835.2  ‐1,082.1  ‐28%

CT 09001 Fairfield NONROAD MAR 353.4 39.6 18.5  ‐334.9  ‐95%

CT 09001 Fairfield NONROAD NMIM 215.8 8.5 9.4  ‐206.4  ‐96%

CT 09001 Fairfield ONROAD MOVES 84.3 71.5 66.4  ‐17.9  ‐21%

CT 09001 Fairfield POINT EGU 3,311.2 849.4 1,421.3  ‐1,889.9  ‐57%

CT 09001 Fairfield POINT NONEGU 154.8 167.8 180.0 25.2 16%

      Fairfield Total    8,036.7 4,294.2 4,530.8 ‐3,505.9 ‐44%

CT 09009 New Haven AREA 3,707.7 2,984.5 2,677.1  ‐1,030.6  ‐28%

CT 09009 New Haven NONROAD MAR 727.4 85.1 35.7  ‐691.6  ‐95%

CT 09009 New Haven NONROAD NMIM 174.1 6.9 7.6  ‐166.5  ‐96%

CT 09009 New Haven ONROAD MOVES 91.8 79.7 74.7  ‐17.2  ‐19%

CT 09009 New Haven POINT EGU 822.7 400.1 398.4  ‐424.3  ‐52%

CT 09009 New Haven POINT NONEGU 55.6 58.5 59.5 3.9 7%

      New Haven Total    5,579.2 3,614.8 3,252.9 ‐2,326.3 ‐42%

     

Total CT  

Portion of

NY‐NJ‐CT Area   

13,615.9 7,909.0 7,783.7 ‐5,832.2 ‐43%

Results set forth in Tables 5.6, 5.7 and 5.8 demonstrate that total emissions of all three PM2.5-related 

pollutants decrease significantly through the maintenance period in Connecticut’s portion of the NY-NJCT area, with PM2.5 emissions decreasing by 22%, NOx by 52% and SO2 by 43% between 2007 and 2025. 

These projected reductions occur due to the currently adopted federal and state control programs 

described in Section 4, with no additional control strategies necessary to maintain the NAAQS in 

Connecticut through the end of the maintenance period. 

Similar reductions are projected for the remaining portions of the nonattainment area. Tables 5.9 and 

5.10 provide preliminary estimates from the MARAMA inventory for the New York and New Jersey 

portions of the area, respectively. Although final emission estimates for New York and New Jersey are 

subject to change, the projected declines in all three states demonstrate that continued compliance during 

the maintenance period will occur, satisfying the CAA Section 175A requirement.

Table 5.8 Connecticut SO2 Emissions Inventory Projections 2007-2025 
59 

5.1.9 Motor Vehicle Emission Budgets 

Under CAA section 176(c), new transportation plans, programs, and projects, such as the addition of new 

highways, must “conform” to (i.e., be consistent with) motor vehicle emission budgets (MVEBs), the part 

of the state’s air quality plan that addresses emissions from cars and trucks. Conformity to the SIP means 

that transportation activities will not cause new air quality violations, worsen existing violations, or delay 

timely attainment of the NAAQS or any interim milestones. If a transportation plan does not conform, 

most new projects that would expand the capacity of roadways cannot move forward. Regulations at 40 

CFR 93 set forth EPA policy, criteria, and procedures for demonstrating and assuring conformity of such 

Interpolated Values Oxides of Nitrogen (NOx) Particulate Matter (PM25‐PRI) Sulfur Dioxide (SO2)

Missing: assumed

same as 2017 Annual Annual Annual Annual Annual Annual Annual Annual Annual

NEW YORK (tons) (tons) (tons) (tons) (tons) (tons) (tons) (tons) (tons)

SECTOR 2007 2017 2025 2007 2017 2025 2007 2017 2025

AREA 41899.7 36640.4 35467.7 9145.6 9403.9 10126.7 29513.2 4412.2 4389.5

NONROAD MAR 24142.8 18316.2 16617.0 916.3 474.7 392.8 6189.5 1199.2 1067.5

NONROAD NMIM 38580.0 22795.0 22795.0 3197.9 2241.8 2241.8 612.9 598.4 598.4

ONROAD MOVES 146859.1 93104.7 50101.2 6690.7 4773.4 3239.5 970.4 945.2 925.0

POINT EGU 26165.8 26132.8 26121.4 2128.7 2102.9 2102.9 40269.6 39926.4 39920.0

POINT NONEGU 10663.9 9596.7 10185.5 303.0 314.4 320.6 3616.7 3552.5 3671.0

NY TOTALS 288311.4 206585.7 161287.8 22382.3 19311.1 18424.3 81172.5 50634.0 50571.5

Interpolated Values Oxides of Nitrogen (NOx) Particulate Matter (PM25‐PRI) Sulfur Dioxide (SO2)

NEW JERSEY

Annual Annual Annual Annual Annual Annual Annual Annual Annual

(tons) (tons) (tons) (tons) (tons) (tons) (tons) (tons) (tons)

SECTOR 2007 2017 2025 2007 2017 2025 2007 2017 2025

AREA 16118.9 15965.9 16057.5 5475.0 5472.5 5617.2 4983.4 452.2 451.7

NONROAD MAR 15719.4 13899.9 12121.0 500.6 287.0 265.7 4552.4 684.3 835.4

NONROAD NMIM 24105.2 13149.8 10110.1 2046.3 1438.4 1147.4 1201.4 34.7 38.7

ONROAD MOVES 81479.5 45687.4 17053.8 2683.5 1873.9 1226.3 592.4 530.8 481.5

POINT EGU 7854.2 6604.3 6226.9 3767.1 1899.0 1955.4 18832.6 2228.1 2399.5

POINT NONEGU 7623.4 6907.4 7200.8 1141.8 1232.0 1287.5 1465.7 1355.0 1441.0

NJ TOTALS 152900.6 102214.8 68770.0 15614.4 12202.9 11499.5 31627.9 5285.1 5647.7

Table 5.9 New York Preliminary Emissions Projections 2007-2025 

Table 5.10 New Jersey Preliminary Emission Projections 2007-2025 
60 

transportation activities to a SIP. Transportation conformity is a requirement for both nonattainment and 

maintenance areas. 

Under the CAA, states submit, at various times, control strategy SIPs and maintenance plans for 

nonattainment areas. These control strategy SIPs (e.g., attainment demonstrations) and maintenance plans 

create MVEBs for criteria pollutants and/or their precursors to address pollution from cars and trucks. 

Per 40 CFR 93, a MVEB must be established for the last year of the maintenance plan. A state may adopt 

MVEBs for other years as well. The MVEB is the portion of the total allowable emissions in the 

maintenance demonstration that is allocated to highway and transit vehicle use and emissions (see 40 

CFR 93.101). The MVEB serves as a ceiling on emissions from an area’s planned transportation system. 

For PM2.5 nonattainment and maintenance areas, MVEBs must be established for direct PM2.5 emissions 

and for NOx emissions77. The MVEB concept is further explained in the preamble to the November 24, 

1993, Transportation Conformity Rule (58 FR 62188). The preamble also describes how to establish the 

MVEB in the SIP and how to revise the MVEB. 

Connecticut has elected to develop MVEBs for PM2.5

78 and NOx for the years 2017 and 2025. The 2017 

budgets will apply to transportation plan years 2017 through 2024, while the 2025 budgets will apply for 

plan years 2025 and later. 

Connecticut requests that the previously approved 2009 PM2.5-related MVEBs be withdrawn from the 

SIP. These budgets were developed using EPA’s now outdated MOBILE6.2 model. Since this 

redesignation request is establishing new MOVES-based MVEBs for 2017 and 2025 that are less than the 

attainment year on-road emissions, it is not necessary to establish 2009 MVEBs with MOVES. Given the 

expected timing for EPA approval of the redesignation/maintenance SIP revision (i.e., late 2012), any 

subsequent conformity determination prepared by the CTDOT/MPOs will not be required to examine 

PM2.5-related emissions for any analysis years prior to the first budget year (i.e., 2017) to be included in 

the revised SIP. 

The MVEBs for 2017 and 2025 are summarized in Table 5.11 for the Connecticut portion of the NY-NJCT area. The 2017 and 2025 MVEBs reflect the total on-road emissions projected by MOVES for those 

years, plus an allocation from the available PM2.5 and NOx “safety margins”. Under 40 CFR 93.101, the 

term “safety margin” is the difference between the attainment level (from all sources) and the projected 

level of emissions (from all sources) in the maintenance plan. All or a portion of the safety margin can be 

allocated to the transportation sector; however, total emissions across all source sectors must remain 

below the attainment level. Connecticut has elected to use only 10% of the available safety margins for 

each pollutant in the 2017 and 2025 MVEBs to account for uncertainties in potential future changes to 

emission factor models and to provide some flexibility in future vehicle miles traveled projections while 

still ensuring that emissions remain well below attainment levels. 

                                                           

77 On-road mobile sources produce less than 2% of total SO2 emissions from all source categories and are judged to 

be de minimis; thus SO2 MVEBs are not necessary. 78 MVEBs established for direct PM2.5 do not include emissions of either re-entrained road dust or construction dust 

from transportation projects; however, emission estimates for both of those categories are accounted for in the area 

source portion of the inventory. 
61 

Table 5.11 Transportation Conformity Budgets for Connecticut’s Portion of 

the NY-NJ-CT Area 

Year 

PM2.5

(tons/year) 

NOx

(tons/year) 

2017 On-Road Inventory 467.4 10,708.0 

 Safety Margin vs. 2007 1083.9 20,837.8 

 10% of Safety Margin 108.4 2,083.8 

2017 Conformity Budget 575.8 12,791.8 

2025 On-Road Inventory 378.9 7,113.4 

 Safety Margin vs. 2007 1371.3 26,146.9 

 10% of Safety Margin 137.1 2,614.7 

2025 Conformity Budget 516.0 9,728.1 

When these budgets are deemed adequate or are approved by EPA (whichever occurs first), subsequent 

transportation plans must show compliance with the 2017 budgets for any analysis years from 2017 

through 2024, and compliance with the 2025 budgets for any analysis years from 2025 onward. 

5.2 Ambient Monitoring Network Commitment 

EPA’s guidance calls for states to commit to maintain an appropriate monitoring network during the 

maintenance period. As described in Section 2.1, DEEP currently operates a monitoring network with 

seven PM2.5 FRM locations in the Connecticut portion of the NY-NJ-CT nonattainment area (see Figure 

2.1). Annual monitoring network plans and five-year network assessment reports are prepared and 

submitted to EPA. These reports describe, among other things, plans for future changes to the monitoring 

network. Potential changes in the number and/or location of monitors are discussed with EPA well in 

advance of implementation. DEEP commits to continuing operation of an appropriate PM2.5 monitoring 

network through the maintenance period. Any potential changes to the existing network will be 

considered in collaboration with EPA through the network planning and assessment procedures to make 

sure the monitoring requirements of the maintenance plan are satisfied. CT DEEP will also continue to 

quality assure the monitoring data to meet the requirements of 40 CFR 58 and enter all data into AQS on 

a timely basis in accordance with federal guidelines. 

5.3 Verification of Continued Attainment 

EPA’s guidance also calls for states to track the progress of the maintenance plan to verify continued 

compliance during the maintenance period. CT DEEP plans to use two indicators to verify continued 

compliance, monitoring data and emissions estimates. CT DEEP will continue to conduct ambient PM2.5 

monitoring in accordance with 40 CFR 58 requirements and expeditiously review data as it becomes 
62 

available to evaluate any risk of impending NAAQS violations. CT DEEP will also regularly review 

available emission inventory updates produced by EPA (e.g., NEI updates or inventories developed for 

potential national rules) and/or CT DEEP (e.g., periodic inventories required by the Federal Consolidated 

Emissions Reporting Rule under 40 CFR 51 Subpart A) to identify any projected increases in emissions 

that might threaten NAAQS compliance. Both of these indicators will be used as potential triggers for 

early action in the contingency plan described below. 

5.4 Contingency Plan 

CAA section 175A and EPA guidance specify that maintenance plans include contingency provisions to 

promptly correct any violation of the NAAQS that occurs after redesignation of the area. Such provisions 

shall include a requirement that the State will implement all measures with respect to the control of the air 

pollutant concerned that were contained in the SIP before redesignation of the area to an attainment area. 

For the purposes of section 175A, a state is not required to have fully adopted contingency measures that 

will take effect without further action by the state in order for the maintenance plan to be approved.79 

However, the contingency plan is considered an enforceable part of the SIP and should ensure that the 

contingency measures are adopted in a timely fashion once they are triggered. The plan should clearly 

identify the measures to be adopted, a schedule and procedure for adoption and implementation, and a 

specific time limit for action by the state. As a necessary part of the plan, the state should also identify 

specific indicators, or triggers, which will be used to determine when the contingency measures need to 

be implemented. 

 

CT DEEP will implement a two-level plan to identify, examine and, if necessary, implement appropriate 

action for monitored PM2.5 levels that approach or violate the 1997 annual or 2006 24-hour PM2.5 

NAAQS. An initial Warning Level Response will be triggered based on PM2.5 levels that approach the 

NAAQS, as described in Section 5.4.1. This voluntary commitment is intended to evaluate the need for 

early actions to prevent violations of the NAAQS from ever occurring during the maintenance period. 

Should early actions not be successful and a violation occurs, an Action Level Response will be triggered, 

as described in Section 5.4.2. 

5.4.1 Warning Level Response 

The initial Warning Level Response is intended to avoid the occurrence of future NAAQS violations by 

tracking air quality monitoring data and available emission inventory estimates to identify when the area 

is at risk of violating the NAAQS. For the 24-hour NAAQS, a violation occurs when the three-year 

average of annual 98th percentile daily values is greater than 35 μg/m3

 at any site. For the annual 

NAAQS, a violation occurs when the three-year average of annual averages is greater than 15 μg/m3

 at 

any site. The Warning Level Response will be triggered if either a single year’s 98th percentile daily 

value or a single year’s annual average exceeds those respective values at any CT DEEP site in the 

maintenance area and is verified. CT DEEP will examine available information to identify contributing 

factors such as atypical meteorological conditions, exceptional events, local changes in source activity, or 

                                                           

79 ”Procedures for Processing Requests to Redesignate Areas to Attainment”; Memorandum from John Calcagni, 

Director, Air Quality Management Division; September 4, 1992. 
63 

source malfunctions or noncompliance. CT DEEP will also evaluate available emission inventories and 

other data repositories (e.g., EPA’s CAMD database of hourly EGU emissions) to determine if 

unexpected emissions increases have occurred. Based on any findings, CT DEEP will evaluate available 

and feasible options and make a judgment on whether any early corrective actions are warranted. 

5.4.2 Action Level Response 

If a verified violation of either PM2.5 NAAQS occurs, CT DEEP will first conduct the same types of 

investigations described above to determine potential causes and available resolutions. If the causes are 

within the jurisdiction and control of CT DEEP (e.g., not predominantly due to interstate transport or 

exceptional events), one or more control measures such as those in the example list below will be pursued 

for implementation. Ultimately, contingency measures to be considered will be selected from a 

comprehensive list of measures deemed appropriate and effective at the time the selection is made. The 

selection of measures will be based upon cost effectiveness, emission reduction potential, economic and 

social considerations, or other appropriate factors. Stakeholder input will be solicited from interested and 

affected persons in the maintenance area prior to selecting any appropriate contingency measures. 

Because it is not possible at this time to determine what control measure will be appropriate at any future 

time during the maintenance period, the list of possible measures below is not intended to be 

comprehensive or exhaustive. 

• Control measures already adopted, but designed to produce additional reductions after the 

verified violation occurred (e.g., mobile source measures that involve fleet turnover); 

• New control measures that may be adopted for other purposes (e.g., Tier 3 or CALEV3); 

• Alternative fuel and/or diesel retrofit programs for fleet vehicle operations; 

• New or more stringent PM2.5, NOx or SO2 controls on stationary sources; 

• Wood stove change out program; 

• “No burn” days during cold weather inversion events; 

• Enhanced idle restrictions; 

• Transportation control measures, selected in consultation with CTDOT and affected local 

metropolitan planning organizations (e.g., traffic flow improvements, transit improvements, trip 

reduction programs, other new or innovative transportation measures) 

CT DEEP commits to pursue adoption of any appropriate measures with a goal of achieving 

implementation within 18 months from the date when the violation triggering the Action Level Response 

is verified. As required by CAA 175A(d), upon verification of a NAAQS violation, CT DEEP also 

commits to implement all measures that were contained in the SIP before the area was redesignated to 

attainment. 

5.5 Commitment to Revise Plan 

CT DEEP commits to submit a revised maintenance plan eight years after EPA finalizes redesignation. 

The revision will demonstrate that attainment will continue to be maintained for the 10 years following 

the initial 10-year period, as required by CAA section 175A(b). 
64 

Chapter 6 Summary and Conclusions 

This TSD justifies CT DEEP’s request to redesignate Connecticut’s portion of the NY-NJ-CT area to 

attainment for the federal 1997 annual and 2006 24-hour PM2.5 NAAQS. As summarized below, this 

redesignation request satisfies all the requirements of Section 107(d)(3)(E) and 175A of the CAA, which 

specify the conditions that must be met for EPA to redesignate an area from nonattainment to attainment. 

6.1 Area Has Attained the NAAQS 

As demonstrated in Section 2, PM2.5 air quality has improved significantly over the last decade 

throughout the NY-NJ-CT nonattainment area. The entire area first achieved attainment levels of the 15 

μg/m3

 annual NAAQS in 2008 and the most recent (i.e., 2010) maximum design value is 12.5 μg/m3. 

Connecticut’s portion of the nonattainment area has measured compliance with the annual NAAQS 

throughout the period, with a maximum 2010 design value of 10.3 μg/m3

. 

The NY-NJ-CT area first achieved compliance with the 35 μg/m3

 24-hour NAAQS in 2009 and has a 

most recent (i.e. 2010) maximum design value of 30 μg/m3

. Connecticut’s portion of the area first 

measured attainment in 2008, with a maximum 2010 design value of 29 μg/m3

. 

6.2 Applicable CAA Section 110 and Title 1 Part D Requirements are Satisfied 

As demonstrated in Section 3.1, Connecticut has submitted “infrastructure SIPs” addressing CAA section 

110(a) requirements, for both the 1997 annual and 2006 24-hour PM2.5 NAAQS. EPA has found 

Connecticut’s infrastructure SIP submittal for the 1997 annual NAAQS to be complete, but has not yet 

issued rulemakings to approve the infrastructure SIPs for either of the NAAQS. Nonetheless, previous 

redesignation rulemakings issued by EPA for other areas have concluded that section 110 elements not 

connected with nonattainment plan submissions and not linked with an area’s attainment status are also 

not applicable requirements for purposes of redesignation because a state remains subject to these 

requirements after an area is redesignated to attainment. 

As described in Section 3.2, CAA Subpart 1 of part D sets forth the basic nonattainment requirements 

applicable to all nonattainment areas. All areas that were designated nonattainment for the 1997 annual 

or the 2006 24-hour PM2.5 NAAQS were designated under this subpart of the CAA and the requirements 

applicable to them are contained in sections 172 and 176. For purposes of evaluating redesignation 

requests, the applicable part D, subpart 1 SIP requirements are contained in sections 172(c)(1)–(9) and in 

section 176. 

States with nonattainment areas are required to submit a plan to reach attainment. Connecticut submitted 

an attainment demonstration for its portion of the 1997 annual PM2.5 nonattainment area in November 
65 

2008, meeting the requirements of CAA sections 172 and 176. EPA has not yet acted on that plan. See 

Section 6.5 for further discussion related to the attainment demonstration. Attainment demonstrations for 

the 24-hour PM2.5 NAAQS are due in December 2012. 

As demonstrated in Section 2, all air quality monitors in the NY-NJ-CT area now comply with both the 

annual and 24-hour NAAQS. EPA has already recognized that the multi-state area has “clean data”, in 

accordance with 40 CFR 51.1004(c), for the annual PM2.5 NAAQS. Connecticut has requested a similar 

“clean data” finding for the 24-hour PM2.5 NAAQS and is awaiting EPA action. The requirement to 

submit the 24-hour PM2.5 NAAQS attainment demonstration would no longer apply if EPA issues a 

“clean data” finding for that NAAQS, or if EPA approves a redesignation request for the 24-hour PM2.5 

NAAQS before the December 2012 due date. 

CAA section 172(c)(3) requires an inventory of actual emissions. Included as part of this redesignation 

request is a 2007 base year emissions inventory that meets the requirement. 

EPA’s PM2.5 implementation rules require states to adopt specified new source review (NSR) permitting 

revisions by July 20, 2012. CT DEEP held a public hearing in November 2011 to consider revisions to 

RCSA sections 22a-174-1 and 22a-174-3a to include significant impact levels, significant emissions rates 

and increments for PM2.5, consistent with EPA’s requirements. CT DEEP anticipates that the revised 

regulations will be submitted as a SIP revision by the end of summer 2012, at which point Connecticut will 

have in place all applicable CAA Section 110 and Title 1 Part D requirements necessary for PM2.5

redesignation.

6.3 Attainment is Due to Permanent and Enforceable Emission Reductions 

Section 4 described adopted federal and state emission control programs that have improved annual and 

24-hour PM2.5 air quality to levels that qualify the area for redesignation to attainment. As was 

summarized in Table 4.1, federal controls include more stringent engine emission and fuel standards for 

on-road and non-road sources, and more restrictive limits on emissions from power plants. State controls 

include tighter emission limits for power plants and other large sources, improvements to PM and visible 

emission requirements for stationary sources, adoption of the CALEV2 program for on-road vehicles, 

enhancements to the on-road vehicle inspection and maintenance program, as well as other measures. 

The combination of these control programs provides an estimated 30% reduction in NOx emissions, 29% 

in SO2 emissions and 4% reduction in direct PM2.5 emissions in Connecticut between 2002 and 2009, 

leading to the improvements in ambient PM2.5 air quality. 
66 

6.4 Maintenance Plan Ensures Continued Attainment 

CAA section 175A establishes the required elements of a maintenance plan for areas seeking 

redesignation from nonattainment to attainment. Section 5 provides Connecticut’s maintenance plan, 

which includes an inventory sufficient to ensure attainment, a demonstration using inventory projections 

that the plan provides for continued NAAQS compliance through the first 10-year maintenance period, a 

commitment to maintain an appropriate monitoring network, methods to track the progress of the 

maintenance plan and contingency measures to be implemented if NAAQS violations occur during the 

maintenance period. 

Having addressed all the requirements of CAA sections 107(d)(3)(E) and 175A, Connecticut requests that 

EPA take action to redesignate the Connecticut portion of the NY-NJ-CT area to attainment status for 

both the 1997 annual and 2006 24-hour PM2.5 NAAQS. 

6.5 Withdrawal of the Attainment Demonstration 

Connecticut submitted an attainment demonstration for Connecticut’s portion of the NY-NJ-CT 1997 

annual PM2.5 nonattainment area in November 2008. EPA subsequently issued a Clean Data 

Determination (CDD) on November 15, 2010 (75 FR 69589), ruling that the NY-NJ-CT area attained the 

1997 annual PM2.5 standard based on 2007-2009 monitoring data. Among other things, the CDD 

suspended the requirement for Connecticut to submit an attainment plan for the 1997 NAAQS. Per 40 

CFR 51.1004(c), suspension of that requirement remains in place until the area is redesignated to 

attainment (at which time the requirement no longer applies) or EPA determines that the area has 

recorded new violations of the NAAQS (at which time the area is again required to submit such a plan). 

Citing the November 2010 CDD ruling, EPA has suggested that Connecticut withdraw its November 

2008 attainment demonstration SIP revision, except for adopted control measures. Based on the 

requirements of 40 CFR 51.1004(c), however, the Department believes withdrawing the attainment 

demonstration prior to the date on which EPA approves the redesignation/maintenance plan would be 

premature since violations measured prior to that date could result in reinstatement of the legal obligation 

to submit an attainment demonstration. 

In light of this concern, the Department hereby withdraws the attainment demonstration SIP, effective one 

day after EPA signs the final rule approving Connecticut’s redesignation request and maintenance plans. 

This timing ensures that either the attainment plan or the maintenance plan will be in place at all times for 

Connecticut’s portion of the area. The Department also specifies this withdrawal does not apply to any 

control measure except for the general permit described in Section 4.2 of this TSD. All other control 

measures remain in the SIP to ensure continued maintenance of the NAAQS.