MARYLAND DEPARTMENT OF THE ENVIRONMENT 

1800 Washington Boulevard  Baltimore MD 21230 

410-537-3000  1-800-633-6101  www.mde.state.md.us 

Martin O’Malley Robert M. Summers, Ph.D. 

Governor Secretary 

Anthony G. Brown 

Lieutenant Governor 

Baltimore Serious Nonattainment Area 

0.08 ppm 8-Hour Ozone 

State Implementation Plan 

Demonstrating Rate of Progress for 2008, 2011 and 2012 

Revision to 2002 Base Year Emissions; and 

Serious Area Attainment Demonstration 

SIP Number: 

 13-07 

June 17, 2013 

Prepared for:

U.S. Environmental Protection Agency 

Prepared by: 

Maryland Department of the Environment
This Page Left Intentionally Blank 
PLAN TO IMPROVE AIR QUALITY IN THE 

BALTIMORE MD REGION

State Implementation Plan (SIP) 

“Serious Area SIP” 

For the 0.08 ppm National Ambient Air Quality Standard for Ozone 

Demonstrating Rate of Progress for 2008, 2011 and 2012; 

Revision to 2002 Base Year Emissions; and 

Serious Area Attainment Demonstration 

for the 

BALTIMORE MD 

NONATTAINMENT AREA 

Prepared by: 

Maryland Department of the Environment 

June 17, 2013 
THIS PAGE LEFT INTENTIONALLY BLANK 
Table of Contents

1.0 Executive Summary...........................................................................................................1

1.1 Introduction ......................................................................................................................... 1

1.2 Emissions.............................................................................................................................. 2

1.3 Control Programs................................................................................................................. 2

1.4 Modeling .............................................................................................................................. 3

1.5 Weight of Evidence .............................................................................................................. 3

2.0 Introduction and Background............................................................................................5

2.1 State Implementation Plans ................................................................................................ 5

2.2 Clean Air Act......................................................................................................................... 6

2.3 Eight‐Hour Ozone Standard ................................................................................................. 7

2.4 SIP Requirements for Moderate Nonattainment Areas...................................................... 8

2.5 SIP Requirements when Reclassifying from “Moderate” to “Serious” ............................... 8

2.6 Ground Level Ozone............................................................................................................. 9

2.7 Air Pollution and the Chesapeake Bay............................................................................... 10

2.8 Health Effects..................................................................................................................... 11

2.9 Maryland‐specific Air Pollution Health Effects.................................................................. 12

2.10 The Impact of Ozone Upon Agriculture............................................................................. 13

2.11 The Air Quality Index (AQI) ................................................................................................ 13

2.12 Sources of Ozone Pollution in the Baltimore Region......................................................... 15

2.13 Frequency of Violation of Federal Health Standard for Ozone ......................................... 17

2.14 Required SIP Principles ...................................................................................................... 18

2.15 Sanctions............................................................................................................................ 19

2.16 Reasonable Further Progress............................................................................................. 19

2.17 Analysis of Reasonably Available Control Measures (RACM)............................................ 19

2.18 Contingency Measures ...................................................................................................... 20

3.0 The 2002 Base‐Year Inventory and Reasonable Further Progress Revisions.....................21

3.1 Background and Requirements ......................................................................................... 21

3.2 Total Emissions by Source.................................................................................................. 21

3.2.1 Point Sources.............................................................................................................................. 21

3.2.2 Quasi‐Point Sources................................................................................................................... 22

3.2.3 Area Sources............................................................................................................................... 22

3.2.4 Mobile Sources........................................................................................................................... 23

3.2.5 Nonroad Sources........................................................................................................................ 24

3.2.6 Biogenic Emissions..................................................................................................................... 26

4.0 Reasonable Further Progress Projected 2008, 2011 and 2012 Inventories.......................27

4.1 Growth Projection Methodology....................................................................................... 27

4.1.1 Growth Projection Methodology for Point Sources: EGAS ........................................................ 28

4.1.2 Growth Projection Methodology for Quasi‐Point Sources........................................................ 28

4.1.3 Growth Projection Methodology: Area Sources........................................................................ 28

4.1.4 Growth Projection Methodology: Nonroad Sources ................................................................. 31

4.1.5 Growth Projection Methodology: Onroad Sources ................................................................... 33

Baltimore Serious Area 8-Hour Ozone SIP Page i
4.1.6 Biogenic Emission Projections.................................................................................................... 34

4.2 Offset Provisions, Emission Reduction Credits and Point Source Growth ........................ 34

4.3

.................................................................................................................... 36

Actual vs. Allowable Emissions in Development of the 2008, 2011 and 2012 Projected

Emissions Inventories

4.4 Projection Inventory Results.............................................................................................. 37

4.5 2008 Controlled Emissions for Reasonable Further Progress ........................................... 37

4.6 2011 Controlled Emissions for Reasonable Further Progress ........................................... 38

4.7 2012 Controlled Emissions for Attainment........................................................................ 38

5.0 2008 Reasonable Further Progress Requirements...........................................................40

5.1 Introduction ....................................................................................................................... 40

5.1.1 Reasonable Further Progress Demonstrated in Previous State Implementation Plans ............ 40

5.2 Guidance for Calculating Reasonable Further Progress (RFP) Emission Target Levels..... 41

5.2.1 2008 VOC and NOx Target Levels............................................................................................... 42

5.3 Compliance with 2008 Reasonable Further Progress Requirements................................ 46

6.0 2011 Reasonable Further Progress Requirements...........................................................48

6.1 Introduction ....................................................................................................................... 48

6.2 Guidance for Calculating Reasonable Further Progress (RFP) Emission Target Levels..... 48

6.2.1 2011 VOC and NOx Target Levels............................................................................................... 48

6.3 Compliance with 2011 Reasonable Further Progress Requirements................................ 50

7.0 2012 Reasonable Further Progress Requirements...........................................................51

7.1 Introduction ....................................................................................................................... 51

7.2 Guidance for Calculating Reasonable Further Progress (RFP) Emission Target Levels..... 51

7.2.1 2012 VOC and NOx Target Levels............................................................................................... 51

7.3 Compliance with 2012 Reasonable Further Progress Requirements................................ 53

8.0 Control Measures............................................................................................................54

8.1 1‐Hour Ozone Control Measures....................................................................................... 54

8.1.1 On‐Road Mobile Measures ........................................................................................................ 54

8.1.2 Area Source Measures ............................................................................................................... 56

8.1.3 Non‐Road Measures................................................................................................................... 59

8.1.4 Point Source Measures .............................................................................................................. 61

8.2 8‐Hour Ozone Control Measures....................................................................................... 62

8.2.1 The Maryland Healthy Air Act (HAA).......................................................................................... 63

8.2.2 Portable Fuel Containers Rule:  Phase I ..................................................................................... 65

8.2.3 Architectural and Industrial Maintenance Coatings Rule .......................................................... 66

8.2.4 Consumer Products Rule:  Phase 1............................................................................................. 67

8.2.5 Industrial Adhesives and Sealants Rule...................................................................................... 68

8.2.6 Portable Fuel Containers Rule:  Phase II .................................................................................... 69

8.2.7 Consumer Products Rule:  Phase II............................................................................................. 70

8.3 Voluntary and Innovative Measures.................................................................................. 71

8.3.1 Regional Forest Canopy Program:  Conservation, Restoration, and Expansion ........................ 71

8.3.2 Clean Air Teleworking Initiative ................................................................................................. 74

8.3.3 High Electricity Demand Day (HEDD) Initiative .......................................................................... 78

8.3.4 Emission Reductions from Transportation Measures................................................................ 79

Baltimore Serious Area 8-Hour Ozone SIP Page ii
9.0 Reasonably Available Control Measure (RACM) Analysis ................................................86

9.1 Analysis Overview and Criteria .......................................................................................... 86

9.1.1 Implementation Date................................................................................................................. 87

9.1.2 Enforceability ............................................................................................................................. 87

9.1.3 Technological Feasibility ............................................................................................................ 88

9.1.4 Economic Feasibility and Cost Effectiveness.............................................................................. 88

9.1.5 Substantial and Widespread Adverse Impacts........................................................................... 88

9.1.6 De Minimis Threshold ................................................................................................................ 88

9.1.7 Advancing Achievement of 0.08 ppm (84 ppb) Standard .......................................................... 89

9.1.8 Intensive and Costly Effort......................................................................................................... 89

9.2 RACM Measure Analysis.................................................................................................... 89

9.2.1 Analysis Methodology................................................................................................................ 89

9.2.2 Analysis Results.......................................................................................................................... 89

9.3 RACM Determination......................................................................................................... 90

10.0 Mobile Source Conformity ..............................................................................................91

10.1 Mobile Emissions Budget & the Baltimore Region Transportation Conformity Process.. 92

10.2 Budget Level for On‐Road Mobile Source Emissions......................................................... 92

10.3 Trends in Mobile Emissions ............................................................................................... 93

11.0 Serious Area Plan Commitments.....................................................................................95

11.1 Schedules of Adopted Control Measures.......................................................................... 95

11.2 Stationary Source Thresholds............................................................................................ 98

12.0 Contingency Measures....................................................................................................99

12.1 Purpose of Chapter............................................................................................................ 99

12.2 Contingency Requirements................................................................................................ 99

12.3 RFP Contingency ................................................................................................................ 99

12.4 Attainment Contingency.................................................................................................. 100

12.5 Conclusions...................................................................................................................... 101

13.0 Attainment Modeling Demonstration ........................................................................... 104

13.1 Modeling Study Overview................................................................................................ 104

13.1.1 Background and Objectives ................................................................................................. 104

13.1.2 Relationship to Regional Modeling Protocols...................................................................... 106

13.1.3 Conceptual Description........................................................................................................ 106

13.2 Domain and Data Base Issues.......................................................................................... 106

13.2.1 Episode Selection................................................................................................................. 106

13.2.2 Size of the Modeling Domain............................................................................................... 107

13.2.3 Horizontal Grid Size ............................................................................................................. 107

13.2.4 Vertical Resolution............................................................................................................... 108

13.2.5 Initial and Boundary Conditions .......................................................................................... 108

13.2.6 Meteorological Model Selection and Configuration............................................................ 108

13.2.7 Emissions Model Selection and Configuration .................................................................... 109

13.2.8 Air Quality Model Selection and Configuration................................................................... 109

13.2.9 Quality Assurance ................................................................................................................ 110

13.3 Model Performance Evaluation ....................................................................................... 110

Baltimore Serious Area 8-Hour Ozone SIP Page iii
13.3.1 Overview.............................................................................................................................. 110

13.3.2 Diagnostic and Operational Evaluation ............................................................................... 111

13.3.3 Summary of Model Performance ........................................................................................ 113

13.4 Attainment Demonstration.............................................................................................. 114

13.4.1 Overview.............................................................................................................................. 114

13.4.2 Modeling Attainment Test................................................................................................... 114

13.4.3 Unmonitored Area Analysis................................................................................................. 117

13.4.4 Emissions Inventories .......................................................................................................... 118

13.4.5 Summary and Conclusions of Attainment Demonstration.................................................. 119

13.5 Procedural Requirements................................................................................................ 123

13.5.1 Reporting ............................................................................................................................. 123

13.5.2 Data Archival and Transfer of Modeling Files...................................................................... 123

14.0 Weight of Evidence Attainment Demonstration............................................................ 125

14.1 Ambient Air Monitoring Measurements and Trends ...................................................... 125

14.1.1 The Ambient Monitoring Network ...................................................................................... 125

14.1.2 Ozone Trends....................................................................................................................... 127

14.1.3 Temperature Adjusted Ozone Trend ................................................................................... 130

14.1.4 Ambient Ozone Precursor Trend ......................................................................................... 132

14.1.5 Supplemental Modeling....................................................................................................... 133

Baltimore Serious Area 8-Hour Ozone SIP Page iv
Appendices 

Appendix A – (Chapter 4) Projection Year Emission Inventories 

Appendix A-1: Projection Year Emission Inventory Methodologies 

Appendix A-2: Point Source Base Year Inventory 

Appendix A-3: Quasi-Point Source Base Year Inventory 

Appendix A-4: Area Source Base Year Inventory 

Appendix A-5: Mobile Source Base Year Inventory 

Appendix A-6: Nonroad Source Base Year Inventory 

Appendix B – (Chapters 5, 6, & 7) Reasonable Further Progress Calculations 

Appendix C – (Chapter 8) Regulatory Support Information 

Appendix D – (Chapter 9) RACM Measures List 

Appendix E – (Chapter 10) Mobile Budget Documentation 

Appendix F – (Chapter 13) Attainment Demonstration 

Appendix F-1: Baltimore Nonattainment Area Ozone Modeling Protocol 

Appendix F-2: Conceptual Description 

Appendix F-3: Episode Selection Documentation 

Appendix F-4: Modeling Domain Boundary 

Appendix F-5: Horizontal Grid Definition for MM5 and CMAQ Modeling Domain 

Appendix F-6: Vertical Layer Definitions for MM5 and CMAQ Modeling Domain 

Appendix F-7: Report on the Set-up and Application of the 36 km CMAQ Model and the 

Extraction of the Boundary Conditions 

Appendix F-8: MM5 Model Performance Evaluation 

Appendix F-9: MM5 Model Configurations 

Appendix F-10: SMOKE Processing Description and Configuration 

Appendix F-11: CMAQ Configuration 

Appendix F-12: CMAQ Performance 

Appendix F-13: Additional Information on the RRF and the Modeled Attainment Test 

Appendix F-14: Future Year Modeling Emissions and Controls 

Baltimore Serious Area 8-Hour Ozone SIP Page v
List of Tables 

Table 1‐1:  Control Measure Summary................................................................................................ 3

Table 2‐1:  Top Ten Sources of Human Made Volatile Organic Compound (VOCs) in the Baltimore

Area in 2002, 2008, 2011 and 2012................................................................................................... 16

Table 2‐2:  Top Ten Sources of Nitrogen Oxides (NOx) in the Baltimore Area in 2002, 2008, 2011

and 2012 ............................................................................................................................................ 17

Table 4‐1:  2002‐2008 Growth Factors.............................................................................................. 29

Table 4‐2:  2002‐2011 Growth Factors.............................................................................................. 29

Table 4‐3:  2002‐2012 Growth Factors.............................................................................................. 29

Table 4‐4:  Emission Reduction Credits ............................................................................................. 34

Table 4‐5:  2008 Projected Controlled VOC & NOx Emissions (tons/day)  Baltimore Nonattainment

Area.................................................................................................................................................... 38

Table 4‐6:  2011 Projected Controlled VOC & NOx Emissions (tons/day)  Baltimore Nonattainment

Area.................................................................................................................................................... 38

Table 4‐7:  2012 Projected Controlled VOC & NOx Emissions (tons/day)  Baltimore Nonattainment

Area.................................................................................................................................................... 39

Table 5‐1:  2002 Reasonable Further Progress Base‐Year Inventory  (Ozone Season tons per day) 43

Table 5‐2:  2002 Reasonable Further Progress Adjusted‐Year Inventory  (Ozone Season tons per

day) .................................................................................................................................................... 44

Table 5‐3:  2008 Reasonable Further Progress Adjusted‐Year Inventory (Ozone Season tons per

day) .................................................................................................................................................... 45

Table 5‐4:  Calculation of Non‐creditable Emissions Reductions (Ozone Season tons per day)....... 45

Table 5‐5:   Calculation of VOC and NOx Target Levels for 2008  (Ozone Season tons per day) ...... 46

Table 5‐6:  Baltimore Nonattainment Area Comparison of 2008 Controlled and Target Inventories  

Ozone Season Daily Emissions (tons per day) ................................................................................... 46

Table 6‐1:  Calculation of Non‐creditable Emissions Reductions (Ozone Season tons per day)....... 49

Table 6‐2:  Calculation of VOC and NOx Target Levels for 2011 (Ozone Season tons per day) ........ 50

Baltimore Serious Area 8-Hour Ozone SIP Page vi
Table 6‐3:  Baltimore Nonattainment Area Comparison of 2011 Controlled and Target Inventories  

Ozone Season Daily Emissions (tons per day) ................................................................................... 50

Table 7‐1:  Calculation of Non‐creditable Emissions Reductions (Ozone Season tons per day)....... 52

Table 7‐2:  Calculation of VOC and NOx Target Levels for 2012 (Ozone Season tons per day) ........ 53

Table 7‐3:  Baltimore Nonattainment Area Comparison of 2012 Controlled and Target Inventories  

Ozone Season Daily Emissions (tons per day) ................................................................................... 53

Table 8‐1:  Summary of Emissions Credits Available from Control Measures .................................. 63

Table 8‐2:  Annual Maryland Healthy Air Act NOx Emissions Reductions (TPY): .............................. 64

Table 8‐3:  Ozone Season Maryland Healthy Air Act NOx Emissions Reductions* ........................... 65

Table 8‐4:  Clean Air Teleworking Time Line...................................................................................... 77

Table 10‐1:  2012 Attainment Year Mobile Budgets for the Baltimore Nonattainment Area .......... 93

Table 11‐1:  Maryland Schedule of Adopted Control Measures Baltimore, Washington DC, and Cecil

County Nonattainment Areas............................................................................................................ 95

Table 11‐2:  Maryland Non‐CTG RACT  Baltimore and Washington Nonattainment Areas.............. 97

Table 12‐1:  Baltimore Nonattainment Area  Comparison of 2012 Target Inventory plus 3%

Contingency and 2012 Controlled Inventories................................................................................ 100

Table 12‐2:  Required Attainment Contingency .............................................................................. 100

Table 12‐3:  Minimum VOC Reductions Required for Attainment Contingency............................. 101

Table 12‐4:  Contingency Measure Calculations.............................................................................. 102

Table 13‐1:  Jurisdictions within the 8‐Hour Ozone Baltimore NAA................................................ 105

Table 13‐2:  Baltimore NAA Statistics for 8‐hour Ozone ................................................................. 111

Table 13‐3:  Individual Site Statistics for 8‐hour Ozone Using 40 ppb Cutoff ................................. 111

Table 13‐4: Individual Site Statistics for 8‐hr Ozone Using 60 ppb Cutoff ...................................... 112

Table 13‐5: Modeling Attainment Test Using EPA Preferred Methodology ................................... 115

Baltimore Serious Area 8-Hour Ozone SIP Page vii
Baltimore Serious Area 8-Hour Ozone SIP Page viii

List of Figures 

Figure 2‐1:  Map of the Baltimore Metropolitan Eight‐hour Ozone Nonattainment Region.............. 7

Figure 2‐2:  Formation of Ground Level Ozone ................................................................................. 10

Figure 2‐3:  The Air Quality Index and Action Guide ......................................................................... 14

Figure 2‐4:  Air‐Watch.net Real‐time Air Quality Data and Forecasts............................................... 15

Figure 2‐5:  8‐Hour Ozone Exceedance Days for the Baltimore Nonattainment Area...................... 18

Figure 8‐1:  Air Quality Action Guide ................................................................................................. 75

Figure 13‐1:  8‐Hour Ozone Baltimore NAA..................................................................................... 105

Figure 13‐2:  Locations of Ozone Monitors in the Baltimore NAA .................................................. 112

Figure 13‐3:  Baltimore NAA 8‐Hour Ozone Base Year (2002) and Future Year (2012) Design Values

.......................................................................................................................................................... 116

Figure 13‐4:  Spatially Interpolated Extent of the 8‐Hour Ozone in the Baltimore NAA Using

Predicted 2012 Design Values ......................................................................................................... 118

Figure 13‐5:  Spatially Interpolated Extent of the 8‐Hour Ozone Within the Baltimore NAA Using

2002 Base Year Design Values......................................................................................................... 120

Figure 14‐1:  Maps of the 2012 Ozone Monitoring Sites................................................................. 126

Figure 14‐2:  Trend in 8‐hour Ozone Design Values per Year for all Maryland Sites ...................... 127

Figure 14‐3:  Trend in 8‐hour Ozone Exceedance Days per Year for all Maryland Sites................. 128

Figure 14‐4:  Trends in Average Daily Peak 8‐hour Ozone for all Maryland Sites Binned by Four‐year

Periods ............................................................................................................................................. 129

Figure 14‐5:  Trend in Diurnal Ozone by 3‐year Rolling Averages for All Maryland Sites from the

Summers (April 1 – October 31) of 1993 through 2009 .................................................................. 130

Figure 14‐6:  Maryland Air Quality: Days above 90F and Ozone Exceedances, 1982‐2008 .......... 131

Figure 14‐7:  Trend in Diurnal NOx by 3‐year Rolling Averages for All Sites in Maryland during the

Summers (April 1 – October 31) of 1993 through 2009 .................................................................. 132
1.0 EXECUTIVE SUMMARY 

This document, the Baltimore Serious Nonattainment Area 0.08 ppm 8-Hour Ozone State 

Implementation Plan (“Serious Area Attainment Plan”), is a plan to improve air quality in the 

Baltimore region to meet the 1997, 0.08 ppm, national ambient air quality standard (NAAQS) for 

ozone (8-hour ozone standard). The Plan consists of two Rate of Progress demonstrations, for the 

periods 2002-2008 and 2008-2011; and an attainment demonstration for 2012. 

Additionally, the plan includes commitments by the state to meet requirements for serious 

nonattainment areas; it also includes commitments by the state to meet additional U.S. 

Environmental Protection Agency (EPA) requirements for the Baltimore region, including a 

contingency plan for 2008 rate of progress, contingency plans for the 2012 rates of progress, and an 

analysis of reasonably available control measures (RACM). The plan presents revised emissions 

inventories for 2002, 2008, 2011, and 2012 based on the MOVES2010a model for estimating onroad vehicle emissions. The analysis methodology is consistent with past statewide inventory 

efforts. 

The Serious Area Attainment Plan is intended to show the progress being made to improve air 

quality in the Baltimore Nonattainment Area and the efforts underway to assure that all necessary 

steps are taken to reach the federal health standard for ground-level ozone by 2012. The plan has 

been prepared by the Maryland Department of the Environment Air and Radiation Management 

Administration to comply with the Clean Air Act Amendments of 1990 (CAAA) and with EPA 

requirements for the Baltimore region as stated in EPA’s reclassification of the Baltimore region 

(77 Fed. Reg. 4901, February 1, 2012). 

1.1 INTRODUCTION 

Ground level ozone is considered a significant health based pollutant and the EPA has set a specific 

national ambient air quality standard for ozone to best protect public health. This standard, known 

as the 8-hour ozone standard, is implemented by the federal Clean Air Act (“CAA” or “the Act”). 

Areas of the county that monitor air pollution above the federal standard are designated 

“nonattainment” and are therefore required to develop and implement air quality plans called State 

Implementation Plans, or SIPs, that show how a particular region will reduce pollution to the point 

where the region will meet the federal standards. 

The Baltimore region, which comprises Baltimore City and the surrounding counties of Baltimore, 

Carroll, Anne Arundel, Howard and Harford, has been designated nonattainment under the 8-Hour 

Ozone standard. The following document explains the process by which the region will reduce 

pollution and meet the federal ozone standard by 2013 which is the designated attainment date for 

the Baltimore region. 

Baltimore Serious Area 8-Hour Ozone SIP Page 1
1.2 EMISSIONS 

A significant portion of this document is related to emissions. Nitrogen oxide (NOx) and volatile 

organic compound (VOC) emissions create ozone under heat and sunlight. Reductions in these 

ozone precursor emissions are a necessity to reduce ozone pollution. The MDE is responsible for 

creating a NOx and VOC emissions inventory that estimates the actual emissions created by all the 

emission sources in our state. Emissions come from a variety of sources including mobile sources 

such as cars and trucks, point sources such as power plants, area sources such as lawnmowers, and 

non-road sources such as construction equipment and all terrain vehicles. 

This document details the current emissions inventory for NOx and VOC and predicted future 

emissions. It is important to project emissions in the future in order to track progress achieved from 

emissions-reducing programs. Also, projected emissions are incorporated into the attainment 

analysis work that actually predicts whether or not a region will meet the air quality standard. 

The good news exhibited by this document is that NOx and VOC emissions are decreasing in the 

Baltimore region. Control programs aimed at reducing emissions have been developed and 

implemented and the reductions required by these programs are significant. Population growth, 

economic growth, and public needs have a tendency, though, to reduce the impact of the emission 

reductions that come from control programs. Despite these obstacles, the overall trend in NOx and 

VOC emissions is downward, and MDE predicts that with additional reductions cleaner air will 

come. 

1.3 CONTROL PROGRAMS 

Over the past several decades the MDE has adopted and implemented numerous control programs 

(laws, regulations, and voluntary measures) that reduce NOx and VOC emissions in Maryland. In 

addition, several new control measures are being adopted specifically to help Maryland attain the 

federal ozone standard. The new programs, in addition to the existing control programs that 

continue to be implemented and enforced, allow Maryland to develop an attainment demonstration 

that shows how Maryland will meet the federal ozone standard. 

The most significant new control program is the Maryland Healthy Air Act (HAA), which 

substantially reduces NOx from Maryland’s older coal burning power plants. The HAA is more 

stringent than the parallel federal rule called the Clean Air Interstate Rule and is the most 

substantial emission control program ever adopted in Maryland. Overall, the HAA reduced 

Maryland power plant NOx emissions by 70% (compared to 2002 levels) in 2009 and by 75% by 

2012. The 2009 and 2012 reductions are a significant part of the attainment scheme developed by 

the MDE to meet the federal ozone standard. 

Addition control programs being implemented to help Maryland meet the federal ozone standard 

include several VOC rules targeted at adhesives and sealants, lower VOC portable fuel containers, 

and lower VOC consumer products. Other non-traditional measures include an aggressive telework 

(also called “telecommuting”) program and a tree canopy program. 

The following is a brief summary of new control measures being implemented to assist Maryland 

with attaining the 8-hour ozone standard. 

Baltimore Serious Area 8-Hour Ozone SIP Page 2
Table 1-1: Control Measure Summary 

   2008 2011 2012

Control Measure VOC NOx VOC NOx VOC NOx

On‐road Mobile Measures 52.86 158.43 61.94 181.42 66.59 192.33

Consumer Products Phase 1 3.70 0.00 3.77 0.00 3.79 0.00

Consumer Products Phase 2 0.00 0.00 0.46 0.00 0.46 0.00

Low VOC Paints (Architectural and  

Maintenance Coatings ‐ AIM) 6.03 0.00 6.19 0.00 6.19 0.00

Portable Fuel Containers Phase 1 6.71 0.00 8.31 0.00 8.35 0.00

Portable Fuel Containers Phase 2 0.00 0.00 0.60 0.00 0.60 0.00

Industrial Adhesives Rule 0.00 0.00 2.63 0.00 2.64 0.00

Nonroad Measures 17.85 8.12 26.33 14.55 29.83 17.30

Railroads (Tier 2) 0.00 1.18 0.00 1.19 0.00 1.20

Healthy Air Act (HAA) 0.00 0.00 0.00 31.86 0.00 37.18

Total 87.14 167.73 110.51 229.35 118.45 248.48

* All control levels are in tons per day (tpd) and all totals are rounded.

1.4 MODELING 

A significant part of the attainment demonstration for Maryland consists of air quality modeling 

analysis. Required by the Act, air quality models are run to examine future air quality conditions 

and whether or not a region will attain the standard by its designated attainment date. The models 

are not relied upon as the only attainment test but are an important part of the attainment 

demonstration for Maryland. 

The air quality modeling analysis completed for this SIP shows the Baltimore Nonattainment Area 

attaining the 8-hour ozone standard. All of the air quality monitors located in the nonattainment 

area are predicted to be at levels consistent with attainment. 

 

1.5 WEIGHT OF EVIDENCE 

As mentioned above, air quality models are not the only tool available to predict attainment of the 

federal ozone standard. A weight of evidence approach can be used to further analyze air quality 

data, trends, and meteorology and complete supplemental modeling. The MDE has completed 

supplemental data analyzes to show that the Baltimore NAA will indeed meet the federal ozone 

standard by 2013. 

Some of the weight of evidence analysis utilized for the Baltimore NAA includes: 

 an analysis of ozone trends; 

 an analysis of ozone precursor trends; and 

 supplemental modeling. 

Baltimore Serious Area 8-Hour Ozone SIP Page 3
Based on the above analyses and air quality modeling performed for the Baltimore NAA, the weight 

of evidence shows that the region will meet the 8-hour ozone standard by the end of the 2012 ozone 

season. 

Baltimore Serious Area 8-Hour Ozone SIP Page 4
2.0 INTRODUCTION AND BACKGROUND 

This document, entitled Baltimore Serious Nonattainment Area 0.08 ppm 8-Hour Ozone State 

Implementation Plan, presents the Maryland Department of the Environment's (MDE) progress in 

adopting and implementing air pollution control programs needed to attain the 8-hour ozone 

standard by 2014 in the Baltimore metropolitan area. Based on the control measures being 

implemented, the related air quality modeling results, and the weight of evidence demonstration 

prepared, there is significant evidence that the Baltimore Nonattainment Area will attain the 8-hour 

ozone standard by June 15, 2013. 

2.1 STATE IMPLEMENTATION PLANS 

The State Implementation Plan (SIP) is a detailed document required for states or regions that do 

not meet air quality levels set by the federal government. The SIP identifies how that State will 

attain and/or maintain the primary and secondary National Ambient Air Quality Standards 

(NAAQS) set forth in section 109 of the Clean Air Act (“CAA” or “the Act") and 40 Code of 

Federal Regulations 50.4 through 50.12 and which includes federally-enforceable requirements. 

Each State is required to have a SIP that contains control measures and strategies that demonstrate 

how each area will attain and maintain the NAAQS. These plans are developed through a public 

process, formally adopted by the State, and submitted by the Governor's designee to EPA. The 

Clean Air Act requires EPA to review each plan and any plan revisions and to approve the plan or 

plan revisions if consistent with the Act. 

SIP requirements applicable to all areas are provided in section 110 of the Act. Part D of Title I of 

the Act specifies additional requirements applicable to nonattainment areas. Section 110 and part D 

describe the elements of a SIP and include, among other components, emission inventories, a 

monitoring network, an air quality analysis, modeling, attainment demonstrations, enforcement 

mechanisms, and regulations which have been adopted by the State to attain or maintain NAAQS. 

EPA has adopted regulatory requirements which detail the procedures for preparing, adopting and 

submitting SIPs and SIP revisions. These regulatory requirements are codified in 40 CFR part 51. 

EPA's action on each State's SIP is promulgated in 40 CFR part 52. 

The contents of a typical SIP fall into several categories: (1) State-adopted control measures which 

consist of either rules/regulations or source-specific requirements (e.g., orders and consent decrees); 

(2) State-submitted comprehensive air quality plans, such as attainment plans, maintenance plans 

rate of progress plans, and transportation control plans demonstrating how these state regulatory and 

source-specific controls, in conjunction with federal programs, will bring and/or keep air quality in 

compliance with federal air quality standards; (3) State-submitted "non-regulatory" requirements, 

such as emission inventories, small business compliance assistance programs, statutes 

demonstrating legal authority, and monitoring networks; and (4) additional requirements 

promulgated by EPA, in the absence of a commensurate State provision, to satisfy a mandatory 

section 110 or part D (CAA) requirement. 

Once the Administrator of the EPA approves a state plan, the plan is enforceable as a state law and 

as federal law under Section 113 of the CAA. If the SIP is found to be inadequate in EPA's 

judgment to attain the NAAQS in all or any region of the state, and if the state fails to make the 

requisite amendments, under Section110(c)(1), the EPA Administrator may issue amendments to 

Baltimore Serious Area 8-Hour Ozone SIP Page 5
the SIP that are binding. EPA is required to impose severe sanctions on the state under three 

circumstances: the state's failure to submit a SIP revision; the finding of the inadequacy of the SIP 

to meet prescribed air quality requirements; and the state's failure to enforce the control strategies 

that are contained in the SIP. Sanctions include withholding federal funds for highway projects 

other than those for safety, mass transit, or transportation improvement projects related to air quality 

improvement or maintenance; and the imposition of 2:1 offset sanctions; these sanctions begin 24 

months after the EPA announcement. No federal agency or department will be able to award a grant 

or fund, license, or permit any transportation activity that does not conform to the most recently 

approved SIP. 

2.2 CLEAN AIR ACT 

The Clean Air Act was passed in 1970 to protect public health and welfare. Congress amended the 

Act in 1990 to establish requirements for areas not meeting the National Ambient Air Quality 

Standards. The Clean Air Act Amendments of 1990 (CAAA) established a process for evaluating 

air quality in each region and identifying and classifying nonattainment areas according to the 

severity of their air pollution problem. The CAAA defines ground-level ozone as a criteria 

pollutant. In 1979 EPA promulgated the 0.12 parts per million (ppm) 1-hour ozone standard. In 

1997, EPA issued a revised and stricter ozone standard of 0.08 ppm1

 measured over an eight-hour 

period. The one-hour ozone standard was consequently revoked in June 2005. The Clean Air Act 

also sets National Ambient Air Quality Standards for five other criteria pollutants; carbon 

monoxide, particulate matter, lead, sulfur dioxide and nitrogen dioxide. 

 

In April 2004, EPA designated the Baltimore metropolitan area as a “moderate” nonattainment area 

for the 0.08 ppm eight-hour ozone standard under Subpart 2 of part D, Title I. The boundaries of the 

Baltimore Nonattainment Area are defined in the Federal Register, (Vol:69, no.84, 4/30/04). The 

Baltimore Nonattainment Area includes Baltimore City and Anne Arundel, Baltimore, Carroll, 

Harford, and Howard counties. A map of the nonattainment area is shown in Figure 2-1. 

 

1

 Note that the 0.08 ppm ozone standard is often referred to as “80 ppb,” “84 ppb,” or “85 ppb” due to issues of how 

0.08 ppm is rounded when converted to units of parts per billion (ppb). 

Baltimore Serious Area 8-Hour Ozone SIP Page 6
Figure 2-1: Map of the Baltimore Metropolitan Eight-hour Ozone Nonattainment Region 

To meet the federal 0.08 ppm 8-hour standard for ozone, nonattainment areas are required to 

develop their SIP documents to reduce ozone-forming emissions by at least 15 percent between 

2002-2008, and to reduce all ozone precursor emissions to a level sufficient to attain the federal 

eight-hour standard by June 15, 2010. However, the region is required to demonstrate attainment of 

the standard by the end of the last ozone season before that date, which is September 2009. 

The region did not meet the Clean Air Act Amendments deadline of June 2010. Analysis suggests 

this was due to transported pollution from outside the region. This analysis was based on ozone 

concentrations measured at high elevation monitors located to the west of the Baltimore NAA. The 

results demonstrated the effect of transported pollution, which contributed potentially up to 50% of 

the pollution on the worst days of summer. 

2.3 EIGHT-HOUR OZONE STANDARD 

In 1997, EPA issued a revised ozone health standard based on an 8-hour measurement to protect 

human health against longer exposure periods. Since the late 1980’s, more than 3,000 published 

health studies have indicated that health effects occur at levels lower than the previous 1-hour 

standard and that exposure times longer than one hour are of concern. EPA established an 8-hour 

standard at 0.08 ppm and defined the new standard as a “concentration-based” form, specifically the 

3-year average of the annual 4th highest daily maximum 8-hour ozone concentration. 

 

EPA changed the form of the standard to a concentration-based form because it more accurately 

reflects actual human exposure and related health effects. Even at relatively low levels, ozone may 

cause inflammation and irritation of the respiratory tract, particularly during physical activity. The 

resulting symptoms can include breathing difficulty, coughing, and throat irritation. Breathing 

ozone can affect lung function and worsen asthma attacks. Ozone can increase the susceptibility of 

Baltimore Serious Area 8-Hour Ozone SIP Page 7
the lungs to infections, allergens, and other air pollutants. Medical studies have shown that ozone 

damages lung tissue and complete recovery may take several days after exposure has ended. 

2.4 SIP REQUIREMENTS FOR MODERATE NONATTAINMENT AREAS 

The Clean Air Act Section 182 (b) requires moderate nonattainment areas to submit state 

implementation plan revisions that meet the following planning requirements: 

 Reasonable Further Progress: 15% emission reduction from baseline within 6 years of 

enactment 

 Attainment demonstration: Due 3 years after CAA Amendments enactment (7/15/07) 

 New Source Review (NSR) and Reasonably Available Control Technology (RACT) major 

source applicability: 100 tons per year (TPY) 

 NSR offsets: 1.15 to 1 

 NSR permits: required for new or modified major stationary sources 

 NOx control for RACT: requirement for major stationary VOC sources also applies to major 

NOx sources 

 RACM/RACT: RACT required for all Control Technique Guideline (CTG) sources and all 

other major sources 

 Inspection and Maintenance (I&M): Basic I&M 

 Stage II vapor recovery: required for all gas stations 

 Contingency measures: required for failure to meet Reasonable Further Progress (RFP) 

milestones or attain 

Before designation as a moderate nonattainment area for the eight-hour standard, the Baltimore 

region was classified as a “severe” nonattainment area for the one-hour ozone standard. The Clean 

Air Act Section 182 (d) requirements for severe nonattainment areas include a number of planning 

requirements that are more stringent than those required for a moderate nonattainment area. Some 

of the more stringent requirements, such as lower permit thresholds, remain in force in the 

Baltimore region and throughout Maryland in order to prevent backsliding. 

The more stringent regulations remaining in force in Maryland are the following: 

 Lower permit threshold for point sources from 100 tons per year, to 25 tons per year; 

 Lower threshold for definition of “Major” source to 25 tons per year for RACT control 

requirements; 

 Require new or expanding sources to offset increased emissions by 1.3:1; 

 Enhanced I&M 

2.5 SIP REQUIREMENTS WHEN RECLASSIFYING FROM 

“MODERATE” TO “SERIOUS” 

On February 1, 2012 (effective March 2, 2012) EPA reclassified the Baltimore, MD Nonattainment 

Area as a “serious” nonattainment area.2

 As a serious nonattainment area for 8-hour ozone National 

 

2

 EPA 40 CFR Part 81, Federal Register, Vol. 77, No. 21, February 1, 2012, pp. 4901-4903.

Baltimore Serious Area 8-Hour Ozone SIP Page 8
Ambient Air Quality Standard (NAAQS), the Baltimore region is required to meet the requirements 

defined in the Clean Air Act, Section 182 (d) and to submit a revised serious area SIP by September 

30, 2012. The “serious” nonattainment area requirements include: 

 Meet all requirements for moderate nonattainment areas 

 Adopt state regulations to meet CAA Section 182 (d) 

 Adopt a contingency plan for 2008 Reasonable Further Progress (RFP) 

 Require new or expanding sources to offset increased emissions by 1.3:1 

 Revise and submit an updated attainment demonstration that reflects MOVES-based motor 

vehicle emissions budgets 

 Demonstrate 3% per year reasonable further progress from 2008-2011 and from 2011-2012 

 Adopt contingency measures for failure to make RFP in those periods and 

 Submit an analysis of Reasonably Available Control Measures for the region. 

 Submit a new attainment demonstration 

2.6 GROUND LEVEL OZONE 

Ground-level ozone is an extremely reactive gas comprised of three atoms of oxygen. Ozone, the 

primary constituent of smog, continues to be a pollution problem throughout many areas of the 

United States. Unlike many other pollutants, ground-level ozone is not directly emitted into the 

atmosphere from a specific source. Instead, ground-level ozone is formed when nitrogen oxides 

(NOx) chemically react with volatile organic compounds (VOCs) through a series of complicated 

chemical reactions in the presence of strong sunshine (ultraviolet light). 

Because ozone formation is greatest when the sunlight is most intense, the peak ozone levels 

typically occur in Maryland during hot, dry, stagnant summertime conditions generally referred to 

as the ozone season (April 1 to October 31). Peak ozone concentrations exhibit a clear seasonal 

cycle, with concentrations rising with the onset of warmer weather in the spring and declining again 

as the autumn approaches. Changing weather patterns can significantly contribute to yearly 

differences in ozone concentrations. Years with summertime weather conditions that are hot and dry 

will generally result in many more days of poor air quality than cool and wet summers. 

Baltimore Serious Area 8-Hour Ozone SIP Page 9
Figure 2-2: Formation of Ground Level Ozone 

The formation of ozone is not an instantaneous process, nor is it limited in geographical scope. 

While many urban areas tend to have high levels of ozone, even rural areas are subject to increased 

ozone levels because wind carries ozone, and the pollutants that form it, hundreds of miles from 

their original sources. Numerous studies and modeling data show compelling evidence that weather 

patterns often result in the transport of ozone and the pollutants responsible for ozone formation, 

well beyond the locality that produced the emissions. In many cases, unhealthy days of air pollution 

experienced in Maryland are exacerbated by pollutants transported into Maryland from neighboring 

states. 

Ground-level ozone can have significant impacts on human health, particularly people with existing 

respiratory disease, the elderly, and children. Ozone also impacts the environment and ecosystem 

health. Scientific evidence suggests that air pollution weakens the immune systems of many types 

of vegetation and can cause significant crop damage. In addition, rain and snow wash air pollution 

deposited on vegetation and architectural surfaces into the streams and rivers of the region and 

finally into the Chesapeake Bay. 

2.7 AIR POLLUTION AND THE CHESAPEAKE BAY 

Typically, air pollution is thought of as smog that affects people’s health and reduces visibility. 

However, air pollution also contributes to land and water pollution that affects the health of the 

Chesapeake Bay’s resources - its fish, shellfish, and other animals. Over the last thirty years, 

research has provided us with increased knowledge of how air pollution can directly affect the Bay. 

Baltimore Serious Area 8-Hour Ozone SIP Page 10
Pollutants released into the air will eventually make their way back down to the earth’s surface. 

Some of the factors that determine how far pollutants can travel through the air include the 

following: the chemical makeup of the pollutant, weather conditions (wind, temperature, humidity), 

type and height of the emission source (smokestack, automobile tail pipe), and the presence of other 

chemicals in the air. Airborne pollutants fall to the earth’s surface by wet deposition (precipitation), 

or dry deposition (settling or adsorption). Airborne pollutants that deposit on the landscape can be 

transported into streams, rivers, and the Bay by runoff or through groundwater flow. 

Excess nitrogen and chemical contaminants from atmospheric deposition impact the Chesapeake 

Bay and its watershed. Too much nitrogen entering the Chesapeake Bay leads to eutrophication, a 

process that causes an accelerated growth of algae. Too much algae in the Bay blocks sunlight 

needed for submerged aquatic vegetation to grow. Also, when the algae die, they sink to the bottom 

of the Bay and decompose in a process that depletes the oxygen in the water. 

The effects of nitrogen can also be seen in acid rain. Nitrogen oxides (NOx) are one of the key air 

pollutants causing acid deposition, which results in adverse effects in aquatic and terrestrial 

ecosystems. Acid deposition increases the acidity of water and soils. Increases in water acidity can 

impair the ability of certain fish and aquatic life to grow, reproduce, and survive. Increases in soil 

acidity can impair the ability of some types of trees to grow and resist disease. 

2.8 HEALTH EFFECTS 

Ozone is a highly reactive gas that reacts strongly with living tissues, as well as many synthetic 

substances. Since 90% of the ozone breathed into the lungs is never exhaled, ozone molecules react 

with lung tissue to cause several health consequences.3 Too much ozone in the air can be harmful to 

people who work or exercise outdoors regularly, anyone with respiratory difficulties, and especially 

to children. The most common symptom that people have when exposed to ozone is pain when 

taking a deep breath. Exposure to ozone can result in both long-term and short-term effects in 

healthy individuals as well as those who are already sensitive to air pollution, such as children, 

asthmatics and the elderly. 

Ozone’s long-term effects may include reduced lung function, scarring of lung tissue, and even 

premature death.4

 Research suggests that repeated exposure to ozone may cause damage to lung 

tissue, thereby reducing lung function. According to EPA, “Long-term exposures to ozone can 

cause repeated inflammation of the lung, impairment of lung defense mechanisms, and irreversible 

changes in lung structure, which could lead to premature aging of the lungs and/or chronic 

respiratory illnesses such as emphysema and chronic bronchitis.”5

 

3

 Sources and Health effects of Ground-Level Ozone, downloaded from 

http://www.dnr.state.wi.us/eq/aie/ozone/b_effect.htm. 

4

 Bell ML, Dominici F, and Samet JM. A Meta-Anaysis of Time-Series Studies of Ozone and Mortality with Comparison 

to the National Morbidity, Mortality, and Air Pollution Study. Epdidemiology 2005; 16:436 445. 

5

 United States Environmental Protection Agecny. (17 July, 1997), Factsheet: EPA’s Revised Ozone Standard. United 

State Environmental Protection Agency, Technology Transfer Network, OAR Policy and Guidance. Retrived on 

December 28, 2005 from the World Wide Web: http://www.epa.gov/ttn/oarpg/naaqsfin/03fact.html/

Baltimore Serious Area 8-Hour Ozone SIP Page 11
Children are at greater risk for ozone-related respiratory problems because their lungs are still 

developing, they breathe more rapidly, and they play outside during the afternoons when ozone is at 

its highest levels. Children also inhale more air; hence, they receive more pollution per pound of 

body weight than adults do.6 Additionally, anyone suffering from lung disease has even more 

trouble breathing when air is polluted with high levels of ozone. Prolonged exposure, even to 

relatively low levels of ozone, can significantly reduce a healthy adult’s lung function.7

Short-term effects of ozone exposure among healthy populations include impaired lung function 

and reduced ability to perform physical exercise. For example, healthy young people developed a 

significant reduction of lung function, additional coughing and breathing pains, and enhanced 

airway reactivity to irritants when exposed to ozone at concentrations of 80-120 parts per billion 

(ppb) for 6.6 to 7.0 hours while exercising moderately.8 Among people who are especially sensitive 

to ozone pollution, short-term effects include increased hospital admissions and emergency room 

visits for respiratory diseases such as asthma. 

In summary, health effects from exposure to ozone can include the following: 

 Increased susceptibility to respiratory infection 

 Impaired lung function and reduced ability to perform physical exercise 

 Severe lung swelling and death, due to short-term exposures greater than 300 ppb 

 Increased hospital admissions and emergency room visits for respiratory diseases 

2.9 MARYLAND-SPECIFIC AIR POLLUTION HEALTH EFFECTS 

According to the U.S. Census Bureau, Census 2000 data, there are 5,296,486 people living in 

Maryland, of whom 1,136,846 were under 15 years of age, and of whom 599,307 were 65 or over9

. 

This means that the total number of children and elderly in Maryland was 1,736,153. 

Approximately one third of Maryland’s population is more likely to suffer the adverse effects of air 

pollution simply as a result of their age. 

 

6

 Ambient Air Pollution: Respiratory Hazards to Children Committee on Environmental Health Pediatrics 1993 91: 

1210-1213. 

7

 Galizia, A. and Kinney, P.L. Long-Term Residence in Areas of High Ozone: Associations with Respiratory Health in 

Nationalwide Sample of Nonsmoking Young Adults. August 1999. Environ Health Perspect, Vol. 107, No. 8, pp. 675-

679 

8

 Foinsbee et al., 1990; Horstman et al., 1990; McDonnell et al., 1991. Out of Breath: A Report on the Health 

Consequences of Ozone and Acidic Air Pollution in Metropolitan Chicago. American Lung Association of Metropolitan 

Chicago, October 19, 1994 

9

 United States Census Bureau. Census 2000 Demographic Profile highlights: Maryland. (Online, follow link to 

Maryland). United Stated Census Bureau, American FactFinder, 2000. Retrieved on March 28, 2005 from the World 

Wide Web: http://factfinder.census.gov/

Baltimore Serious Area 8-Hour Ozone SIP Page 12
According to an April 200610 report from the American Lung Association, the group of people with 

respiratory disease in the state of Maryland includes: 

 274,967 adult asthmatics and 100,370 child asthmatics; 

 147,226 residents with chronic bronchitis; and 

 57,310 residents with emphysema. 

2.10 THE IMPACT OF OZONE UPON AGRICULTURE 

Because ozone formation requires sunlight, periods of high ozone concentration coincide with the 

agriculture growing season in Maryland. Ozone damage to plants can occur with or without any 

visible signs. Consequently, many farmers are unaware that ozone is reducing their yields. Ozone 

enters the plant’s leaves through its gas exchange pores (stomata), just as other atmospheric gases 

do in normal gas exchange. The ozone then dissolves in the water within the plant and reacts with 

other chemicals, causing a variety of problems. 

Ozone damage in the plant causes photosynthesis to slow, resulting in slower plant growth. Such 

ozone induced problems also decrease the numbers of flowers and fruits a plant will produce, and 

impair water use efficiency and other functions. Plants weakened by ozone may be more susceptible 

to pests, disease, and drought.

 

Most studies of the economic impact of air pollution on agriculture have found that a 25 percent 

reduction in ambient ozone would provide benefits of at least $1-2 billion annually in the United 

States. Studies of soybean yields at the University of Maryland found a 10 percent loss of the 

soybean crop due to current levels of ozone in the state. The same study showed that ozone 

exposure causes the loss of 6-8 percent of winter wheat and 5 percent of the corn crop yields to 

Maryland farmers.

2.11 THE AIR QUALITY INDEX (AQI) 

The AQI is an index used for reporting forecasted and daily air quality. The AQI uses both a colorcoded and numerical scale to report how clean or polluted the air is and what associated health 

effects might be of concern. The AQI focuses on health effects people may experience within a few 

hours or days after breathing polluted air. The AQI is calculated for five major pollutants regulated 

by the Clean Air Act: particulate matter, ozone, carbon monoxide, sulfur dioxide, and nitrogen 

dioxide. 

 

10 America Lung Association State of the Air, April 2006, pp. 1-207 

Baltimore Serious Area 8-Hour Ozone SIP Page 13
Figure 2-3: The Air Quality Index and Action Guide 

Using the Air Quality Index, the Maryland Department of the Environment and the Metropolitan 

Washington Council of Governments (COG) issue daily air quality forecasts for the Baltimore 

metropolitan area, Washington metropolitan area, Western Maryland, and the Eastern Shore. 

Extended range forecasts provide a three-day forecast so people can better plan their week and take 

the opportunity to arrange car pools, take mass transit, or take other actions to limit pollution when 

air quality is predicted to be unhealthful. 

MDE and COG issue the air quality forecasts to local media and hundreds of businesses and 

individuals throughout the region. Anyone can sign up to receive the free, daily email by visiting 

the Clean Air Partners web site at http://www.cleanairpartners.net/. The Clean Air Partners web site 

provides the public with easy-access local and national air quality information. Clean Air Partners 

offers daily AQI forecasts and real-time AQI conditions throughout most of Maryland, the District 

of Columbia, and Northern Virginia. Users of Clean Air Partners may also sign-up for AirAlerts to 

receive real-time email notifications when air quality reaches unhealthy levels in the region. 

Baltimore Serious Area 8-Hour Ozone SIP Page 14
Figure 2-4: Air-Watch.net Real-time Air Quality Data and Forecasts 

2.12 SOURCES OF OZONE POLLUTION IN THE BALTIMORE REGION 

There are a number of diverse sources that discharge VOCs and NOx, the two primary pollutants 

responsible for ozone formation. Human made sources, called anthropogenic sources, are divided 

into four categories: point, area, on-road mobile and non-road mobile sources. A fifth category, 

"biogenic" emissions, includes all naturally occurring sources of VOC emissions from trees, crops 

and other forms of vegetation. 

Point sources are primarily manufacturing businesses that produce emissions equal to or greater 

than 25 tons per year (tpy) of VOCs or NOx. Large industrial plants such as power plants and 

chemical manufacturers are examples of point sources. 

Area sources are smaller sources of air pollution whose emissions are too small to be measured 

individually. Examples of area sources include commercial and consumer products (such as paints 

and hairspray), bakeries, dry cleaners, gasoline refueling stations, printing facilities, and autobody 

refinishing shops. 

Baltimore Serious Area 8-Hour Ozone SIP Page 15
Sources of air pollution that are not stationary are referred to as mobile sources and are split into 

two categories: on-road mobile sources and non-road mobile sources. The former include cars, 

vans, trucks and buses (i.e. vehicles that operate on highways). Non-road mobile sources include 

boats, lawn and garden equipment, construction equipment and locomotives.

Table 2-1: 

Top Ten Sources of Human Made Volatile Organic Compound (VOCs) in the Baltimore Area 

in 2002, 2008, 2011 and 2012 

 

 VOC 

(Tons/Day) 

Rank Source Category Source 2002 2008 2011 2012 

1 On-Road Mobile Cars, Buses, Trucks 72.48 50.12 44.54 40.23

2 Nonroad Lawn and Garden Total 34.52 22.36 19.37 18.01

3 Area Commercial & Consumer Solvents 24.75 22.33 22.33 22.43

4 Area Portable Fuel Containers 18.68 13.00 11.23 11.29

5 Area Architectural Surface Coatings 18.28 13.43 13.78 13.85

6 Area Industrial Surface Coating 16.97 18.44 19.09 19.23

7 Point Utilities and Other Stationary Sources 12.74 14.31 15.13 15.48

8 Nonroad Pleasure Craft Total 8.68 6.68 5.40 4.94

9 Area Surface Cleaning/Degreasing 8.09 8.81 9.12 9.19

10 Area Gasoline Marketing 6.67 7.50 7.93 8.07

 221.85 176.97 167.92 162.73

*The emissions estimates above are rounded to the nearest whole number.  The figures are MDE’s best estimates.  

Total VOC emissions in the Baltimore area were 382 tons per day in 2002 and 285.7 tons per day in 2008.  Biogenic

emissions account for 314.7 tons/day of VOC emissions in the Baltimore region.   

Baltimore Serious Area 8-Hour Ozone SIP Page 16
Table 2-2: 

Top Ten Sources of Nitrogen Oxides (NOx) in the Baltimore Area in 2002, 2008, 2011 and 

2012 

 NOx 

(Tons/Day) 

Rank Source Category Source 2002 2008 2011 2012 

1 On-Road Mobile Cars, Buses, Trucks 202.22 125.69 104.62 93.47

2 Point Utilities and Other Stationary Sources 102.19 111.64 82.26 81.44

3 Nonroad Construction and Mining Total 21.52 18.66 16.52 15.55

4 Nonroad Industrial Total 7.40 5.32 3.75 3.25

5 Nonroad Railroad Total 6.26 5.61 5.43 5.38

6 Nonroad Lawn and Garden Total 5.86 5.17 4.70 4.35

7 Area Incineration 3.84 3.84 3.84 3.84

8 Nonroad Commercial Total 3.27 3.07 2.88 2.76

9 Area Residential Fuel Combustion 2.66 2.78 2.83 2.84

10 Nonroad Pleasure Craft Total 0.76 0.96 1.01 1.01

 355.99 282.75 227.85 213.90

*The emissions estimates above are rounded to the nearest whole number.  The figures are MDE's best estimates.  

The total emission of NOx in the Baltimore area was 541 tons per day in 2002 and 320 tons per day in 2008.    

2.13 FREQUENCY OF VIOLATION OF FEDERAL HEALTH STANDARD 

FOR OZONE 

Since the Clean Air Act Amendments of 1990, Maryland has made significant improvements in the 

quality of air. National, state, and local programs have all contributed to dramatically limiting the 

amount of pollution that is generated, which has reduced the number of days that unhealthful air is 

experienced throughout the region. Mandated reductions in emissions from businesses and 

industries and technological improvements in automobiles have brought about a steady progress in 

air quality. 

Baltimore Serious Area 8-Hour Ozone SIP Page 17
Baltimore, MD NAA 8-Hour Ozone Exceedance Days per Year

43 44

37

43 42

51

58

28 30

50

23

48

40

36

30

51

40

16

26

37

11 10

23

26

15

3

28

16

65 65

0

10

20

30

40

50

60

70

19801982

1984

1986

1988

1990

19921994

1996

199820002002

2004

2006

2008

Number of Days

Figure 2-5: 8-Hour Ozone Exceedance Days for the Baltimore Nonattainment Area 

The federal 8-hour ozone standard is set at 0.08 parts per million of ozone averaged over an eighthour period. Figure 2-5 applies the eight-hour standard to historic data and shows the number of 

days that would have exceeded levels under the new standard. The figure also clearly shows an 

improving trend in the Baltimore regions air quality since 1980. While annual fluctuations can be 

attributed to weather (hot, stagnant summers are favorable for ozone formation), the downward 

trend is indicative of controls on sources of air pollution and the resulting levels of ozone precursors 

present in the ambient air. 

2.14 REQUIRED SIP PRINCIPLES 

Section 110 of the 1990 CAAA specifies the conditions under which EPA approves SIP 

submissions. These requirements are being followed by the Maryland Department of the 

Environment in developing this air quality plan (SIP). In order to develop effective control 

strategies, EPA has identified four fundamental principles that SIP control strategies must adhere to 

in order to achieve the desired emissions reductions. These four fundamental principles are outlined 

in the General Preamble to Title I of the Clean Air Act Amendments of 1990 at Federal Register 

13567 (EPA, 1992a). The four fundamental principles are as follows: 

1. Emissions reductions ascribed to the control measure must be quantifiable and measurable; 

Baltimore Serious Area 8-Hour Ozone SIP Page 18
2. The control measures must be enforceable, in that the state must show that they have 

adopted legal means for ensuring that sources are in compliance with the control measure; 

3. Measures are replicable; and 

4. The control strategy must be accountable in that the SIP must contain provisions to track 

emissions changes at sources and to provide for corrective actions if the emissions 

reductions are not achieved according to the plan. 

2.15 SANCTIONS 

EPA must impose various sanctions if the State does not submit a plan, submits a plan that the EPA 

does not approve, or fails to implement the plan. These sanctions include withholding federal 

highway funding, withholding air quality planning grants, and imposing a federal plan (“federal 

implementation plan.”). Failure to submit or implement a plan will have significant consequences 

for compliance with conformity requirements and the imposition of 2:1 offset requirements. 

2.16 REASONABLE FURTHER PROGRESS 

As a serious area, EPA requires the two Reasonable Further Progress demonstrations for the 

Baltimore Nonattainment Area; one for the period 2002 – 2008 and the second for 2008 – 2011.11 

EPA’s implementation guidance requires that a serious ozone nonattainment area, such as the 

Metropolitan Baltimore region, with an approved 15% VOC reduction plan for the period 1990-

1996 (required for former 1-hour ozone non-attainment areas) demonstrate a 15% Reasonable 

Further Progress by 2008 and 3% per year Reasonable Further Progress by 2011. Chapter 5 contains 

the Baltimore region’s reasonable further progress demonstration for the years 2002-2008, and 

Chapter 6 provides the RFP demonstration for 2008-2011. The region needs to fulfill the 2008-2011 

reasonable further progress requirements by January 1, 2012. 

In order to demonstrate reasonable further progress, a region must show that its expected emissions, 

termed “controlled inventories,” of NOx and VOC will be less than or equal to the target levels set 

for the end of the reasonable further progress period, or “milestone year”. For the RFP period 2002-

2008, the “target inventories” of emissions are the maximum quantity of anthropogenic emissions 

permissible during the 2008 milestone year. For the RFP period 2008-2011, the “target inventories” 

of emissions are the maximum quantity of anthropogenic emissions permissible during the 2011 

milestone year. 

2.17 ANALYSIS OF REASONABLY AVAILABLE CONTROL MEASURES 

(RACM) 

An extensive list of potential control measures was analyzed and evaluated against criteria used for 

potential RACM measures. Individual measures must meet the following criteria: reduce emissions 

by the beginning of the Baltimore region’s 2008 ozone season (April 1, 2008); are enforceable; are 

technically feasible; are economically feasible, defined as a cost of $3,500 to $5,000 per ton or less; 

 

11 Final Rule to Implement the 8-Hour Ozone National Ambient Air Quality Standard, Federal Register, Vol 70, No. 

228, Nov.29, 2005, pp. 71612-71705. 

Baltimore Serious Area 8-Hour Ozone SIP Page 19
would not create substantial or widespread adverse impacts within the region; and the emissions 

from the source being controlled must exceed a de minimis threshold, defined as 0.1 tons per day. 

Based on the analysis completed for the Baltimore Nonattainment Area which relied heavily upon a 

very formal RACM analysis completed for the Washington DC Nonattainment Area (where MDE 

actively participated in a significant RACM workgroup) there were no identified RACM measures 

that if implemented would advance attainment in the Baltimore Nonattainment Area. 

2.18 CONTINGENCY MEASURES 

In the event that the reductions anticipated in the 2011 Reasonable Further Progress demonstrations 

or the 2012 attainment demonstration are not realized within the timeframes specified, there must be 

contingency measures ready for implementation. EPA issued guidance that says that contingency 

measures must provide for a 3% reduction in adjusted 2002 base year inventory for both Reasonable 

Further Progress and attainment. A minimum of 0.3 percent VOC must be included. The total 

required reductions for RFP contingency equate to approximately 7.76 TPD of VOC, which 

Maryland meets. The measures proposed as contingency measures are listed in Chapter 12, which 

contains detail on these measures, how they would be implemented and enforced, and the level of 

emission reduction benefits expected. 

Baltimore Serious Area 8-Hour Ozone SIP Page 20
3.0 THE 2002 BASE-YEAR INVENTORY AND REASONABLE 

FURTHER PROGRESS REVISIONS 

 

3.1 BACKGROUND AND REQUIREMENTS 

The 2002 Base-Year Inventory is published in a separate document, "2002 Base Year Emissions 

Inventory & QA/QC Plan Maryland," June 15, 2006. This document was submitted to the U.S. 

Environmental Protection Agency (EPA) Region III. MDE prepared the document, and the 

document remains intact to fulfill the State Implementation Plan (SIP) inventory requirement of the 

CAA. It is available for inspection at the Maryland Department of the Environment, Air and 

Radiation Management Administration, 1800 Washington Boulevard, Suite 730, Baltimore, 

Maryland 21230. 

The emissions inventory covers the Baltimore nonattainment area, shown in Figure 2-1, which is 

classified as a moderate nonattainment area for ozone by the EPA. The 2002 emissions inventory is 

the starting point for calculating the emissions reductions required to meet the goal of a 15% 

reduction in VOC/NOx emissions, from anthropogenic sources, by 2008. Meeting this 2008 goal 

means meeting reasonable further progress requirements prescribed for moderate nonattainment 

areas by the Clean Air Act Amendments (CAAA) and EPA. 

 

This separately published document, which was previously submitted to EPA, addresses emissions 

of volatile organic compounds (VOCs), nitrogen oxides (NOx), and carbon monoxide (CO) on a 

typical summer ozone season day and annual basis. Included in the inventory are anthropogenic 

(human-made) stationary, non-road and on-road mobile sources; and biogenic (naturally occurring) 

sources of ozone precursors. 

When updating or revising a SIP, EPA requires that the latest models and inventory methodologies 

be used when calculating Reasonable Further Progress (RFP) goals and target levels. As such, 

updates to the RFP inventories are documented in Appendix A-1. 

3.2 TOTAL EMISSIONS BY SOURCE 

3.2.1 Point Sources 

For emissions inventory purposes, point sources are defined as stationary, commercial, or industrial 

operations that emit more than 10 tons per year (tons/year) of VOCs or 25 tons/year or more of 

NOx or CO. The point source inventory consists of actual emissions for the base-year 2002 and 

includes sources within the geographical area of the Baltimore Nonattainment Area. 

3.2.1.1 Reasonable Further Progress Revisions 

No revisions to the point source emissions inventory were necessary for Reasonable Further 

Progress purposes. 

Baltimore Serious Area 8-Hour Ozone SIP Page 21
3.2.2 Quasi-Point Sources 

The Maryland Department of the Environment Air and Radiation Management has identified 

several facilities that due to size and/or function are not considered point sources. These 

establishments contain a wide variety of air emission sources, including traditional point sources, 

on-road mobile sources, off-road mobile sources and area sources. For each particular 

establishment, the emissions from these sources are totaled under a single point source and 

summary documents include these “quasi-point” sources as point sources. 

Quasi-point sources will include all emissions at the facility regardless of whether they are 

classified as point, area, nonroad, or mobile source emissions. These emissions are actual emissions 

reported for the facilities. The Baltimore Nonattainment Area has the following quasi-point 

sources: 

 Baltimore Washington International Airport (BWI) 

 Aberdeen Proving Grounds 

These emissions have been included as “point source” in summary documents. 

3.2.2.1 Reasonable Further Progress Revisions 

No revisions to the quasi-point source emissions inventory were necessary for Reasonable 

Further Progress purposes. 

3.2.3 Area Sources 

Area sources are sources of emissions too small to be inventoried individually and which 

collectively contribute significant emissions. Area sources include smaller stationary point sources 

not included in the states' point source inventories; for example, printing establishments, dry 

cleaners, and auto refinishing companies, as well as non-stationary sources. 

 

Area source emissions typically are estimated by multiplying an emission factor by some known 

indicator of collective activity for each source category at the county or county-equivalent level. 

An activity level is any parameter associated with the activity of a source, such as production rate or 

fuel consumption that may be correlated with the air pollutant emissions from that source. For 

example, the total amount of VOC emissions emitted by commercial aircraft can be calculated by 

multiplying the number of landing and takeoff cycles (LTOs) by an EPA-approved emission factor 

per LTO cycle for each specific aircraft type. 

 

Several approaches are available for estimating area source activity levels and emissions. These 

include apportioning statewide activity totals to the local inventory area and using emissions per 

employee or other unit factors. For example, solvent evaporation from consumer and commercial 

products such as waxes, aerosol products, and window cleaners cannot be routinely determined for 

many local sources. The per capita emission factor assumes that emissions in a given area can be 

reasonably associated with population. This assumption is valid over broad areas for certain 

Baltimore Serious Area 8-Hour Ozone SIP Page 22
Baltimore Serious Area 8-Hour Ozone SIP Page 23

activities such as dry cleaning and small degreasing operations. For some other sources an 

employment based factor is more appropriate as an activity surrogate. 

3.2.3.1 Reasonable Further Progress Revisions 

No revisions to the area source emissions inventory were necessary for Reasonable Further 

Progress purposes. 

3.2.4 Mobile Sources 

On-road mobile sources include all vehicles registered to use the public roadways. The 

predominant emissions source in this category is the automobiles, although trucks and buses are 

also significant sources of emissions. 

The computation of highway vehicle emissions required two primary entities: a) vehicle emission 

factors and b) vehicle activity. 

The emission factors are generated by using MOBILE6.2, which is the latest version of U.S. EPA’s 

emission factor model as far as the base year inventory. Vehicle activity (vehicle miles traveled, or 

“VMT”) is usually obtained from two sources: a) the Maryland State Highway Administration 

(SHA), and b) Baltimore Metropolitan Council (BMC) staff. VMT data from SHA, based on 

vehicle traffic counts on the roadway system, is mainly used for the rural counties. The Baltimore 

Region Transportation Board-provided transportation modeled link-based data is used in the 

emission modeling of the Baltimore Ozone Nonattainment Area. 

In a simple modeling scenario, the product of the emission factor and vehicle miles traveled should 

yield emission levels. Proper units and conversions are used to arrive at reasonable emission 

estimates. 

In a complex modeling scenario, many emissions types, such as exhaust, evaporative, diurnal, 

crankcase, and refueling emissions, are computed separately and treated with the appropriate 

activity levels. 

MOBILE6 expects enormous amount of local data input, such as the fleet characteristics, fleet 

mileage accrual rates, speed, fuel parameters, inspection and maintenance (I/M) program in place, 

and weather data. 

In MOBILE6 emission factor model, the total highway vehicle population is characterized by the 

following 16 composite vehicle type categories: 

LDV - Light-Duty Vehicles (Passenger Cars) 

LDT1 - Light-Duty Trucks 1 

LDT2 - Light-Duty Trucks 2 

LDT3 - Light-Duty Trucks 3 

LDT4 - Light-Duty Trucks 4 

HDV2B- Class 2b Heavy Duty Vehicles 

HDV3 - Class 3 Heavy Duty Vehicles 

HDV4 - Class 4 Heavy Duty Vehicles 

HDV5 - Class 5 Heavy Duty Vehicles 

HDV6 - Class 6 Heavy Duty Vehicles 

HDV7 - Class 7 Heavy Duty Vehicles 

HDV8A- Class 8a Heavy Duty Vehicles 
HDV8B- Class 8b Heavy Duty Vehicles 

HDBS - School Buses 

HDBT - Transit and Urban Buses 

MC - Motorcycles 

These composite vehicle types are further classified into 28 vehicle types, depending on whether 

they use gasoline or diesel fuel. For example, all motorcycles are gasoline based and transit and 

urban buses are diesels. School buses can be either gasoline-driven or diesel-driven vehicles. 

MOBILE6 also allows for the modeling of other fuel type vehicles such as hybrids and alternate 

fuel vehicles (AFV) as a special case in a complex modeling initiative. 

The MOBILE6 model produces emission factors for each of the 28 vehicle types and one composite 

factor for all vehicle types. 

A post-processing system takes care of all emission computations of the modeling domain by 

aggregating the emissions from roads/links appropriate to the area. It also produces meaningful 

reports by area, by vehicle type and by roadway type. 

3.2.4.1 Reasonable Further Progress Revisions 

EPA replaced the previous model for estimating on-road mobile source emissions, 

MOBILE6.2, with a new model, MOVES (MOtor Vehicle Emission Simulator). 

MOVES2010 is the state-of-the-art upgrade to EPA’s modeling tools for estimating 

emissions from highway vehicles, based on analysis of millions of emission test results and 

considerable advances in the Agency’s understanding of vehicle emissions. 

This SIP presents revised emissions inventories for 2002, 2008, 2011, and 2012 based on the 

MOVES2010a model for estimating on-road vehicle emissions. The analysis methodology 

is consistent with past statewide inventory efforts including the 2008 National Emissions 

Inventory (NEI) submission. Also, the methodology includes the use of statewide traffic 

roadway data obtained from the State Highway Administration and custom post-processing 

software (PPSuite) to calculate hourly speeds and prepare key traffic input files to the 

MOVES2010a emission model. MOVES2010a is built in to the PPSuite software package. 

MDE used MOVES2010a to estimate volatile organic compounds (VOCs), nitrogen oxides 

(NOx), and carbon monoxide (CO) emissions for this SIP revision. 

3.2.5 Nonroad Sources 

Emissions for all nonroad vehicles and engines except for those at BWI airport (aircraft, ground 

support equipment (GSE) and, auxiliary power units (APU)), locomotives, and diesel marine 

vessels were calculated using EPA’s NONROAD2005.0.0 (dt. 12/02/2005) model. Since the time it 

was first issued on 12/02/2005, this model version has undergone several corrections. The base year 

nonroad inventory was created using what was the version current as of 3/21/2006. 

 

Emissions from the “nonroad vehicles and engines” category result from the use of fuel in a diverse 

collection of vehicles and equipment, including those in the following categories: 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 24
 Recreational vehicles, such as all-terrain vehicles and off-road motorcycles; 

 Logging equipment, such as chain saws; 

 Agricultural equipment, such as tractors; 

 Construction equipment, such as graders and back hoes; 

 Industrial equipment, such as fork lifts and sweepers; 

 Residential and commercial lawn and garden equipment, such as leaf and snow blowers; and 

 Aircraft ground support equipment. 

 

The nonroad model estimates emissions for each specific type of nonroad equipment by multiplying 

the following input data estimates: 

 

 Equipment population for base year (or base year population grown to a future year), 

distributed by age, power, fuel type, and application; 

 Average load factor, expressed as average fraction of available power; 

 Available power, in horsepower; 

 Activity, in hours of use per year; and 

 Emission factor with deterioration and/or new standards. 

 

The emissions are then temporally and geographically allocated using appropriate allocation factors. 

3.2.5.1 Reasonable Further Progress Revisions 

EPA replaced the previous model for estimating off-road mobile source emissions, 

NONROAD2005, with a new version, NONROAD2008. The main change for 

NONROAD2008 is the inclusion of emission reductions associated with two rules finalized 

in 2008: 

o Diesel (CI) recreational marine standards in the Locomotive/Marine final rule 

(Federal Register Vol 73, No. 88, page 25098, May 6, 2008). 

o Small Spark Ignition (SI) and SI Recreational Marine final rule (Federal Register 

Vol 73, No. 196, page 59034, October 8, 2008). 

NONROAD2008 predicts substantially lower hydrocarbons (HC) and CO and somewhat 

lower NOx and PM emissions than NONROAD2005 while using comparable scenario 

inputs. 

Aircraft (military, commercial, general aviation, and air taxi) and auxiliary power units (APU) 

operated at airports, along with locomotives and diesel marine vessels, are also considered nonroad 

sources and are included in the nonroad category. 

 

Baltimore Washington International Airport (BWI) and the Maryland Aviation Administration 

(MAA) provided all types of airport emissions for BWI airport. Aircraft and APU emissions for 

other counties were calculated by MDE through landing and take-off data surveys. Emissions from 

locomotives and commercial diesel marine vessels were also produced by the MDE. 

Baltimore Serious Area 8-Hour Ozone SIP Page 25
3.2.6 Biogenic Emissions 

 

An important component of the inventory is biogenic emissions. Biogenic emissions are those 

resulting from natural sources. Biogenic emissions are primarily VOCs that are released from 

vegetation; they are emitted throughout the day. Biogenic emissions of NOx include lightning and 

forest fires. EPA used a biogenic computer model (BEIS3.12) to estimate biogenic emissions for 

each county in the country for all twelve months of the year 2002. 

Emissions data for the Baltimore Nonattainment Area was acquired from the EPA website 

(ftp://ftp.epa.gov/EmisInventory/2002finalnei/biogenic_sector_data/). EPA has recommended that 

states use these emissions in case they do not have their own estimated biogenic emissions. The 

Baltimore, Maryland ozone non-attainment area decided to use the inventories provided by the 

EPA. 

Baltimore Serious Area 8-Hour Ozone SIP Page 26
4.0 REASONABLE FURTHER PROGRESS PROJECTED 2008, 2011 

AND 2012 INVENTORIES 

Part II of EPA’s rule to implement the 8-hour NAAQS required the Baltimore, MD as a moderate 

ozone nonattainment area to achieve, by 2008, a 15 percent emissions reduction, including either 

VOC or NOx emissions or any combination of the two.12 By re-classifying as a “serious” ozone 

nonattainment area, the Baltimore, MD region is further required to reduce VOC and NOx 

emissions by 3 percent per year by 2011. An inventory for the attainment year 2012 is also required 

for the region. 

The reductions must be calculated from the anthropogenic emissions levels reported in the 2002 

Base-Year Inventory after those levels have been adjusted to reflect the expected growth in 

emissions between 2002 and 2008/2011/2012. The 2002 Base-Year Inventory was described in 

Chapter 3. This chapter presents the 2008, 2011 and 2012 Projection Inventories, that is, the 

estimation of the levels of emissions to be expected in those years before the consideration of 

emission controls. 

 

The 2008, 2011 and 2012 projected inventories are derived by applying the appropriate growth 

factors to the 2002 Base-Year Emissions Inventory. EPA guidance describes four typical indicators 

of growth. In order of priority, these are as follows: (1) product output, or the amount of product 

being produced; (2) value added, or “the value of a product sold by a firm less the value of the 

goods purchased and used by the firm to produce the product”;13 (3) earnings, and (4) employment. 

Surrogate indicators of activity, for example population growth, are also acceptable methods. 

 

Round 6B Cooperative Forecasting results (population, household and employment projections), 

prepared and officially adopted by the Baltimore Metropolitan Council (BMC) were used to project 

emissions from area sources. Projections for onroad emissions were developed using MOVES 

model (please see Appendix E for information on mobile source emissions). 

EPA’s nonroad model, NONROAD2008, was used for developing the 2008, 2011 and 2012 

nonroad model inventories. BMC’s Round 6B Cooperative Forecasting results and the Economic 

Growth Analysis System (EGAS) model were used to project growth in the additional nonroad 

source categories such as railroad locomotives, marine vessels and airports. The EGAS model was 

also used to project growth in point source emissions. 

4.1 GROWTH PROJECTION METHODOLOGY 

 

The following sections describe the method followed to determine the projected inventories for 

2008, 2011 and 2012. 

 

12 EPA 40 CFR Parts 51, 52 & 90, Federal Register. Vol.70, No. 228, Nov. 29, 2005, pp.71612-71705. 13 STAPPA-ALAPCO-EPA Emission Inventory Improvement Program, Emission Projections, prepared by The PechanAvanti Group, Springfield, VA, December 1999. 

Baltimore Serious Area 8-Hour Ozone SIP Page 27
4.1.1 Growth Projection Methodology for Point Sources: EGAS 

 

The growth in point source emissions is projected using EGAS version 5.0. Point source emissions 

for 2002 are provided from the state data sources. The model is run with the 2002 emissions data 

grouped by Source Classification Code (SCC). Growth factors generated from the Bureau of Labor 

Statistics national economic forecast and the baseline regional economic forecast are applied to each

SCC grouping. 

For source category listings and descriptions, projection methods and data sources, and surrogate 

growth indicators, please refer to Appendix A-1. 

Point source emission projection data is contained in Appendix A-2. 

4.1.2 Growth Projection Methodology for Quasi-Point Sources 

Quasi-point sources will include all emissions at the facility regardless of whether they are 

classified as point, area, nonroad, or mobile source emissions. These emissions are actual emissions 

reported for the facilities. Actual emissions will be forecast to the projection years using surrogates 

specific to each quasi-point source. The growth factor indicators and their sources are listed below 

by facility (names are in italics): 

Quasi-Point Source Surrogate Growth Indicator 

Baltimore Washington International Airport 

(BWI): 

Aircraft LTOs FAA Aircraft Operations Forecasts 

Mobile Source Emissions FAA Enplanement Forecasts 

Aberdeen Proving Grounds BRAC Population Estimates 

For source category listings and descriptions, projection methods and data sources, and surrogate 

growth indicators please refer to Appendix A-1. 

Quasi-point source emission projection data is contained in Appendix A-3. 

4.1.3 Growth Projection Methodology: Area Sources 

 

Base-year area source surrogate growth factors for 2002 were calculated using 2002 population, 

household, and employment data. Linearly interpolating between 2000 and 2005 data produced the 

2002 data. Dividing Round 6B population, household, and employment forecasts for the analysis 

year by the derived 2002 values for the region produced the growth factors for the periods of 2002 

to 2008, 2002 to 2011 and 2002 to 2012. Categories related to the transportation and storage of 

gasoline were grown using projected vehicle miles traveled (VMT) for analysis years. Area 

projection inventories are contained in Appendix B. The growth factors used for the 2002-2008, 

2002-2011, and 2002-2012 projection years are presented in Tables 4-1, 4-2 and 4-3. The growth 

factors were applied to emissions categories by specific jurisdictions. 

Baltimore Serious Area 8-Hour Ozone SIP Page 28
Table 4-1: 2002-2008 Growth Factors14

 

Jurisdiction Employment Population Household VMT

 Anne Arundel County 1.0742 1.0447 1.0734 1.1346 

 Baltimore City 1.0533 1.0070 1.0196 1.1101 

 Baltimore County 1.1343 1.0510 1.0591 1.1223 

 Carroll County 1.0909 1.1091 1.1204 1.1358 

 Harford County 1.1429 1.0963 1.1191 1.1408 

 Howard County 1.0238 1.1002 1.1126 1.1105 

Table 4-2: 2002-2011 Growth Factors15

Jurisdiction Employment Population Household VMT

 Anne Arundel County 1.1119 1.0622 1.1065 1.1776 

 Baltimore City 1.0783 1.0146 1.0390 1.1557 

 Baltimore County 1.1860 1.0696 1.0808 1.2099 

 Carroll County 1.1238 1.1441 1.1620 1.2096 

 Harford County 1.2083 1.1438 1.1778 1.1991 

 Howard County 1.0382 1.1434 1.1680 1.1776 

Table 4-3: 2002-2012 Growth Factors16

Jurisdiction Employment Population Household VMT

 Anne Arundel County 1.1266 1.0676 1.1168 1.1960 

 Baltimore City 1.0822 1.0144 1.0432 1.1709 

 Baltimore County 1.1930 1.0730 1.0853 1.2346 

 Carroll County 1.1327 1.1534 1.1739 1.2325 

 Harford County 1.2262 1.1558 1.1949 1.2287 

 Howard County 1.0426 1.1547 1.1866 1.1960 

 

14 Employment, population, and household growth factors are based on BMC Final Round 6B Cooperative Forecasts. 

VMT growth factors are based on VMT estimates provided by the MDE Mobile Sources Control Program. 

15 Ibid. 16 Ibid. 

Baltimore Serious Area 8-Hour Ozone SIP Page 29
The 2008, 2011 and 2012 emissions for area sources are calculated by multiplying the 2002 baseyear area emissions by the above growth factors for the appropriate year for each jurisdiction. Each 

area source category was matched to an appropriate growth surrogate based on the activity used to 

generate the base-year emission estimates. Surrogates were chosen as follows: 

 

Surface Coating – depending on whether emission factors were based on employment or 

population, surrogate chosen varied with individual subcategories. For example, automobile 

refinishing category was grown using employment, as the emission factor was based on it, but 

population was chosen for growing traffic markings as its emission factor was based on population. 

 

Commercial/Consumer Solvent Use - population was chosen as the growth surrogate since 2002 

emissions are based on per capita emission factors. 

 

Residential Fuel Combustion – households was chosen as the growth surrogate. 

Industrial/Commercial/Institutional Fuel Combustion - employment was chosen as the growth 

surrogate except for the commercial/institutional coal combustion category, where no growth was 

assumed. 

 

Vehicle Fueling (Stage II) and Underground Tank Breathing - all gasoline marketing categories 

were based on vehicle miles traveled (VMT) data since VMT is an appropriate surrogate for 

gasoline sales. Emission factors for these categories are based on gasoline sales. 

 

Open Burning - population was chosen as the growth surrogate as yard wastes, land debris, and the 

like increase with population. 

 

Structural Fires, Motor Vehicle Fires – population was chosen as the growth surrogate. 

 

Publicly Owned Treatment Works (POTW) – households was chosen as the growth surrogate. 

 

Dry Cleaning - population was chosen as the surrogate. 

 

Graphic Arts - population was used to estimate growth since emissions are based on per capita 

emission factors. 

 

Surface Cleaning - employment growth was used as the surrogate. 

 

Tank Truck Unloading –growth in VMT was applied to this category since base-year emissions 

are calculated using gasoline sales. 

 

Municipal Landfills - Base-year emissions are estimated using data on total refuse deposited. 

Population was chosen as a surrogate since deposited waste is from the general population rather 

than industrial facilities. 

 

Asphalt Paving - population was chosen as the surrogate since base-year emissions are calculated 

using per capita emission factors. 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 30
Bakeries, Breweries - population was chosen as the surrogate. 

 

Soil/Groundwater Remediation - zero growth was applied to this category. The number of 

remediations during the ozone season, used to generate base-year emissions, does not directly 

correlate to population, households, or employment growth. 

 

General Aviation and Air Taxi Emissions - Emissions from small airports were projected using 

the EGAS 5.0 model. The Maryland Aviation Administration (MAA) provided commercial aircraft 

operations information at Baltimore Washington International (BWI) Airport. Emissions were 

calculated using FAA-approved activity data and the Emissions Dispersion Modeling system 

(EDMS) model. Emissions were grown by FAA Terminal Area Forecasts (TAFs). 

Aircraft Refueling Emissions - emissions from refueling of aircrafts was projected based on 

employment. 

 

Portable Fuel Container Emissions - emissions from portable fuel containers were grown based 

on population. 

 

Railroad Locomotives - employment growth was used as the surrogate. 

 

Forest Fires, Slash Burning, Prescribed Burning – zero growth was applied to this category. 

Accidental Oil Spills - zero growth was applied to this category. 

Incineration– zero growth was applied to this category.

 

Pesticide Application - zero growth was applied to this category. 

For source category listings and descriptions, projection methods and data sources, and surrogate 

growth indicators, please refer to Appendix A-1. 

Area source emission projection data is contained in Appendix A-4. 

4.1.4 Growth Projection Methodology: Nonroad Sources 

 

The 2008, 2011 and 2012 nonroad source inventories were created through the use of EPA’s 

NONROAD2008 model. Locomotives, marine diesel vessels, and aircraft are not included. The 

base year 2002 nonroad source inventory was revised for Reasonable Further Progress using 

NONROAD2008 model. 

Nonroad model runs were made for the metropolitan Baltimore region for a typical summer 

weekday. 

 

Methodology to prepare inputs for the ozone season day is provided below. 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 31
Temperature: 

Temperature data were acquired from the National Climatic Data Center (NCDC). Hourly average 

temperature data were collected for Baltimore Washington International (BWI) station for the top 

ten 8-hour maximum ozone days between 2002 and 2004. Then minimum, maximum, and average 

temperatures were computed from this hourly temperature dataset. 

 

Fuel inputs: 

Month-specific data for fuel Reid Vapor Pressure (RVP) and oxygen weight percent were collected 

from the Baltimore Regional Transportation Board (BRTB), the Baltimore Metropolitan Council 

(BMC), and the MDE Mobile Sources Control Program. The data was averaged for the period May 

through September to obtain ozone season average inputs. Model defaults were used for gas, diesel, 

marine diesel, and CNG/LPG sulfur percent. Stage II controls were not assumed and were set at 

zero for the model runs. 

Model inputs (temperature, fuel, and other parameters) are listed below: 

NONROAD Model Inputs (all NR Runs)

Options File

Fuel RVP for gas 6.6 Minimum Temp (F) 65.55

Oxygen Weight % 2.44 Maximum Temp (F) 87.60

Gas S % 0.0339 Average Temp (F) 76.80

Diesel S % 0.2284 State II Control % 0

Marine Diesel S % 0.2318 EtOH Blend Market % 75.1

CNG/LPG Sulfur % 0.003 EtOH Volume % 9.3

Period 

Episode Inventory Year Requested (2002, 2008, 2011, 2012) 

Period Seasonal 

Season Summer 

Type Typical Day 

Day Weekday 

Region 

Region County 

Selected Anne Arundel County MD Harford County MD 

Baltimore County MD Howard County MD 

Carroll County MD Baltimore City MD 

Sources 

Active All Sources

Since the nonroad model does not generate emissions for aircraft, auxiliary power units (APU), 

locomotives, and commercial diesel marine vessels, these were either projected from the base year 

Baltimore Serious Area 8-Hour Ozone SIP Page 32
emissions using the BMC Round 6B Cooperative Forecast or the EGAS model. Below are the 

details for projecting emissions for the above mentioned individual nonroad categories. 

 

Aircraft emissions (military, commercial, general aviation, air taxi)

 

As previously noted, Maryland Aviation Administration (MAA) provided all types of airport 

activity data and emissions for Baltimore Washington International (BWI) airport. Aviation 

emissions from BWI were grown by FAA Terminal Area Forecasts (TAFs). Emissions were 

calculated using FAA-approved activity data and the Emissions Dispersion Modeling system 

(EDMS) model. 

 

General aviation and air taxi emissions from small airports were projected using the EGAS 5.0 

model. 

 

Auxiliary power units emissions 

These emissions were only available for BWI airport. Emissions were calculated using FAAapproved activity data and the EDMS model. 

 

Ground support equipment emissions 

The NONROAD2005.1.0 model generated these emissions for small airports. BWI ground support 

equipment (GSE) emissions were generated using the EDMS model, which calculated emissions 

based on actual aircraft operations. The NONROAD model calculates emissions based on GSE 

population only and therefore emissions generated this way are considered less accurate than the 

ones generated by the EDMS model. 

 

Commercial Diesel Marine Vessels 

Base year emissions from commercial diesel marine vessels were grown to future years using 

employment as the surrogate. 

 

Railroad 

Railroad or locomotive emissions were grown using employment as the surrogate. 

For source category listings and descriptions, projection methods and data sources, and surrogate 

growth indicators please refer to Appendix A-1. 

Nonroad mobile source emission projection data is contained in Appendix A-6. 

4.1.5 Growth Projection Methodology: Onroad Sources 

 

The 2008, 2011 and 2012 mobile source inventories were created through the MOVES model. A 

full description of this mobile emission estimating process can be found in Appendix E of this 

report. 

Baltimore Serious Area 8-Hour Ozone SIP Page 33
4.1.6 Biogenic Emission Projections 

 

Biogenic emission inventories are the same as those used for the 2002 base year for Baltimore, MD 

ozone nonattainment region. Year-specific biogenic inventories were not estimated. Base year 

emissions for 2002 were estimated by EPA using BEIS3.12 model. No 2008 biogenic inventories 

were prepared as these inventories are not used to determine rate of progress. 

4.2 OFFSET PROVISIONS, EMISSION REDUCTION CREDITS AND 

POINT SOURCE GROWTH 

 

The Clean Air Act (CAA or “the Act”) requires that emissions growth from major stationary 

sources in nonattainment areas be offset by emissions reductions that would not otherwise be 

achieved by other mandated controls. The offset requirement applies to all new major stationary 

sources, and to existing major stationary sources that have undergone major modifications. At the 

same time, existing sources’ emissions increases resulting specifically from increases in capacity 

utilization are not subject to the offset requirement. 

For the purposes of the offset requirement, major stationary sources include all stationary sources 

exceeding an applicable size cutoff. The NSR thresholds for the Baltimore Nonattainment Area are 

25 tpy VOC and 25 tpy NOx. 

EPA has issued guidance on the inclusion of emission reduction credits in the projected emissions 

inventory. The guidance states: 

The base year inventory includes actual emissions from existing sources and would not 

normally reflect emissions from units that were shutdown or curtailed before the base year, 

as these emissions are not ‘in the air.’ To the extent that these emission reduction credits are 

to be considered available for use as offsets and are thus ‘in the air’ for purposes of 

demonstrating attainment, they must be specifically included in the projected emissions 

inventory used in the attainment demonstration along with other growth in emissions over 

the base year inventory. This step assures that emissions from shutdown and curtailed units 

are accounted for in attainment planning.17 

MDE has included emission reduction credits in the attainment demonstration projected inventory. 

A list of these emission reduction credits and associated facilities is shown in Table 4-4. 

Table 4-4: Emission Reduction Credits 

Facility Name 

State 

Facility 

Identifier 

Pollutant 

Code 

Emission 

Reduction 

Credits 

(TPY) 

Alltrista Metal Services 510-0508 NOX 2

Andrews Air Force Base 033-0655 NOX 15

Armco Stainless/ 510-0340 NOX 16

Bausch & Lomb 023-0019 NOX 1

 

17 Federal Register, Vol. 71, No. 243, page 75910, December 19, 2006. 

Baltimore Serious Area 8-Hour Ozone SIP Page 34
Facility Name 

State 

Facility 

Identifier 

Pollutant 

Emission 

Reduction 

Credits 

Code (TPY) 

Bethlehem Steel 005-0147 NOX 701

Chevron Asphalt 510-0072 NOX 49

Coca Cola 510-0242 NOX 5

Crown Cork & Seal - Duncanwood 510-0320 NOX 10

G. Heileman Brewing (Strohs) 005-0129 NOX 24

General Electric 027-0020 NOX 82

General Motors - Truck & Bus 510-0354 NOX 119

Giant - Bakery (930 King St) 031-0224 NOX 2

Gordon D. Garratt 510-0360 NOX 1

Grief Brothers Corp. 005-0134 NOX 1

Millenium Inorganic Chemicals 510-0109 NOX 30

Proctor & Gamble 510-0185 NOX 12

Pulaski Incinerator 510-0498 NOX 302

Quebecor Printing 003-0274 NOX 2

Rohr Industries 043-0104 NOX 6

Schluderberg-Kurdle 510-0283 NOX 19

Showell Farms 047-0036 NOX 8

Simpkins Industries - River Rd 027-0005 NOX 87

TPS Technologies, Inc. -Todd's La. 005-2131 NOX 16

Trigen (Leadenhall St) 510-2796 NOX 33

U.S.Can - Sparrows Pt. (Amer Nat) 005-0183 NOX 7

Westport 510-0006 & Riverside 005-0078 510-0006 NOX 1480

WR Grace 510-0076 NOX 17

3M Commercial Graphics 013-0052 VOC 30

Alltrista Metal Services 510-00508 VOC 11

American Mouldings 043-0191 VOC 69

Armco/Balto. Specialty Steel 510-0340 VOC 11

BARCO – Fairlawn 510-2854 VOC 5

Bata Shoe 025-0003 VOC 18

Bausch & Lomb 023-0019 VOC 16

Baycraft Fiberglass Engineering 025-0231 VOC 10

Bethlehem Steel 005-0147 VOC 0

BGE - SNG Plant 005-1054 VOC 7

Blue Chip Products 015-0058 VOC 35

Carpenter Insulation 043-0189 VOC 146

CE Stevens Packaging (printer) 510-2900 VOC 10

Cello Professional Products 025-0145 VOC 0

Cherokee Sanford 033-0565 VOC 0

Chevron Asphalt 510-0072 VOC 2

Conoco Sun Gasoline Terminal 510-0676 VOC 27

Baltimore Serious Area 8-Hour Ozone SIP Page 35
Facility Name 

State 

Facility 

Identifier 

Pollutant 

Emission 

Reduction 

Credits 

Code (TPY) 

Constellation - Westport 510-0006 & Riverside 005-

0078 510-0006 VOC 23

Crown Central Petroleum 003-0234 VOC 21

Crown Cork & Seal - Duncanwood 510-0320 VOC 13

Crown Cork & Seal - Hurlock 019-0073 VOC 96

CSX Minerals 043-0110 VOC 10

Ecko-Glaco Ltd. 005-0310 VOC 27

G. Heileman Brewing Co. (Strohs) 005-0129 VOC 48

General Motors - Electromotive 005-0692 VOC 15

General Motors - Truck & Bus 510-0354 VOC 0

Giant - Bakery - 930 King St 031-0224 VOC 0

Grief Brothers Corporation 005-0134 VOC 0

LeSaffre Yeast 510-0191 VOC 179

Mail-Weil Graphics 019-0097 VOC 8

Maryland Paper Box 005-2220 VOC 15

Metalfab - Grove Road 021-0317 VOC 11

PPG Industries 001-0005 VOC 28

Pulaski Incinerator 510-0498 VOC 11

Quebecor Printing 003-0274 VOC 322

Rohr Industries 043-0104 VOC 4

Schlumberger Malco, Inc. 005-1614 VOC 12

Simpkins Industries (River Rd) 027-0005 VOC 7

Thomas Mfg. 005-0240 VOC 22

Tidewater Industrial Corp. 011-0039 VOC 11

TPS Technologies (Todd's La.) 005-2131 VOC 4

U.S.Can-Sparrows Pt. (Amer Nat) 005-0183 VOC 90

4.3 ACTUAL VS. ALLOWABLE EMISSIONS IN DEVELOPMENT OF 

THE 2008, 2011 AND 2012 PROJECTED EMISSIONS INVENTORIES 

 

For the purposes of calculating the projection emissions inventories, EPA guidance specifically 

outlines the circumstances under which emissions projections are to be based on actual or allowable 

emissions. For sources or source categories that are subject to a pre-1990 regulation and that the 

state does not anticipate subjecting to additional regulation, emissions projections should be based 

on actual emissions levels. Actual emissions levels should also be used for emissions projections 

for sources or source categories that were unregulated as of 1990. For sources that are expected to 

be subject to post-1990 regulations, projections should be based on new allowable emissions. 

 

To simplify comparisons between the base-year and the projected year, EPA guidance states that 

comparisons should be made only between like emissions: actual to actual, or allowable to 

Baltimore Serious Area 8-Hour Ozone SIP Page 36
allowable, not actual to allowable. As a result, all base-year and all projection-year emissions 

estimates are based on actual emissions. 

 

Maryland regulation defines "actual emissions" and “allowable emissions” as follows:18

“Actual emissions” means the average rate, in tons per year, at which a source discharged a 

pollutant during a 2-year period which precedes the date of a completed application for an 

NSR source or other specified date, and which is representative of normal source operation... 

Actual emissions shall be calculated using the source's operating hours, production rates, and 

types of materials processed, stored, or combusted during the selected time period. 

“Allowable emissions” means the maximum emissions a source or installation is capable of 

discharging after consideration of any physical, operational, or emissions limitations 

required by [state regulations] or by federally enforceable conditions which restrict 

operations and which are included in an applicable air quality permit to construct, permit to 

operate, secretarial order, plan for compliance, consent agreement, court order, or applicable 

federal requirement.

 

4.4 PROJECTION INVENTORY RESULTS 

 

Chapter 8 of this SIP describes the control measures that have been implemented or will be 

implemented from 2008 through 2012 that will reduce emissions. Most control measures are 

required by federal or state regulations. Projected controlled inventories for 2008, 2011 and 2012 

assume a number of control measures, as identified in Chapter 8, to be in place by these years. 

 

Tables 4-5, 4-6, and 4-7 present the projected controlled emissions for the 2008 reasonable further 

progress, 2011 reasonable further progress, and 2012 attainment years resulting from 

implementation of the control measures. 

4.5 2008 CONTROLLED EMISSIONS FOR REASONABLE FURTHER 

PROGRESS 

 

The projection of 2008 controlled emissions is simply the 2008 uncontrolled emissions minus the 

emission reductions achieved from the federal control measures and the reasonable further progress 

control measures implemented by states for the 8-hour ozone SIP. This information is presented in 

Table 4-5. Controlled inventories are contained in Appendix A. Details on mobile source controlled 

inventories can be found in Appendix E. 

 

18 See Code of Maryland Regulations (COMAR) 26.11.01.01. 

Baltimore Serious Area 8-Hour Ozone SIP Page 37
Table 4-5: 

2008 Projected Controlled VOC & NOx Emissions (tons/day) 

Baltimore Nonattainment Area 

Emission 

Source 

Category 

Baltimore NAA 

VOC Emissions*

Baltimore NAA 

NOx Emissions*

Point 15.63 122.65 

Area 108.17 8.43 

Non-road 44.04 42.85 

Mobile 50.12 125.69 

Total 217.96 299.62 

 *Small discrepancies may result due to rounding.

4.6 2011 CONTROLLED EMISSIONS FOR REASONABLE FURTHER 

PROGRESS 

 

The projection of 2011 controlled emissions is simply the 2011 uncontrolled emissions minus the 

emission reductions achieved from the federal control measures and the reasonable further progress 

control measures implemented by states for the 8-hour ozone SIP. This information is presented in 

Table 4-6. Controlled inventories are contained in Appendix A. Details on mobile source controlled 

inventories can be found in Appendix E. 

Table 4-6: 

2011 Projected Controlled VOC & NOx Emissions (tons/day) 

Baltimore Nonattainment Area 

Emission 

Source 

Category 

Baltimore NAA 

VOC Emissions*

Baltimore NAA 

NOx Emissions*

Point 16.79 95.21 

Area 106.07 8.54 

Non-road 38.26 38.12 

Mobile 44.54 104.62 

Total 205.65 246.48 

 *Small discrepancies may result due to rounding.

4.7 2012 CONTROLLED EMISSIONS FOR ATTAINMENT 

 

The projection of 2012 controlled emissions is simply the 2012 uncontrolled emissions minus the 

emission reductions achieved from the federal control measures and the reasonable further progress 

Baltimore Serious Area 8-Hour Ozone SIP Page 38
control measures implemented by states for the 8-hour ozone SIP. This information is presented in 

Table 4-7. 

Table 4-7: 

2012 Projected Controlled VOC & NOx Emissions (tons/day) 

Baltimore Nonattainment Area 

Emission 

Source 

Category 

Baltimore NAA 

VOC Emissions*

Baltimore NAA 

NOx Emissions*

Point 17.19 94.79 

Area 106.79 8.56 

Non-road 35.69 36.05 

Mobile 40.23 93.47 

Total 199.90 232.88 

 *Small discrepancies may result due to rounding.

Baltimore Serious Area 8-Hour Ozone SIP Page 39
5.0 2008 REASONABLE FURTHER PROGRESS REQUIREMENTS 

5.1 INTRODUCTION 

 

In June 2005 EPA revoked the one-hour ozone standard and published implementation guidance for 

the 8-hour ozone standard. EPA classified the metropolitan Baltimore region as being in moderate 

nonattainment of the 8-hour ozone standard; EPA made this classification under the Clean Air Act 

(CAA or “the Act”) Subpart 2, Section 182(b). 

 

As a moderate nonattainment area, the metropolitan Baltimore region is required to demonstrate 

reasonable further progress towards attainment by 2008.19 EPA’s implementation guidance 

requires that a moderate area, such as Baltimore, with an approved 15% VOC reduction plan for the 

period 1990-1996 (required for former 1-hour ozone non-attainment areas) demonstrate a 15% R

by 2008. This chapter contains the Baltimore region’s reasonable further progress demonstration f

the years 2002-2008. The region needs to fulfill the 2002-2008 reasonable further progress 

requirements by January 1, 2009. 

FP 

or 

 

In order to demonstrate reasonable further progress, a region must show that its expected emissions, 

termed “controlled inventories,” of NOx and VOC will be less than or equal to the target levels, or 

“target inventories” set for the end of the reasonable further progress period, or “milestone year”. 

For the RFP period 2002-2008, the target inventories of emissions are the maximum quantity of 

anthropogenic emissions permissible during the 2008 milestone year. 

 

This section describes the methodology used to establish the regional target inventories and 

controlled inventories for 2008. Because the expected NOx and VOC emissions are less than or 

equal to the target levels in the analysis, the Baltimore region meets the RFP requirements for 2008. 

The reasonable further progress emission inventories utilize the latest EPA models (MOVES and 

NONROAD2008) providing revised up-to-date emission estimates. 

5.1.1 Reasonable Further Progress Demonstrated in Previous State 

Implementation Plans 

Since 1990, the Clean Air Act has required ozone nonattainment areas to demonstrate progress 

towards attaining the ozone standard. This requirement is referred to as the reasonable further 

progress requirement, or RFP. During the period 1990-1996, areas in nonattainment of the one-hour 

ozone standard were required to reduce VOC emissions by 15%. Since 1996, regions have been 

required to demonstrate a 9% rate of progress every three years until the region’s attainment date. 

 

19 Final Rule To Implement the 8-Hour Ozone National Ambient Air Quality Standard—Phase 2; Final Rule To 

Implement Certain Aspects of the 1990 Amendments Relating to New Source Review and Prevention of Significant 

Deterioration as They Apply in Carbon Monoxide, Particulate Matter and Ozone NAAQS; Final Rule for Reformulated 

Gasoline, Federal Register, Vol 70, No. 228, Nov.29, 2005, pp. 71612-71705. 

Baltimore Serious Area 8-Hour Ozone SIP Page 40
Baltimore Serious Area 8-Hour Ozone SIP Page 41

 

The CAA included restrictions on the use of control measures to meet the 15% requirements. 

Reductions in ozone precursors resulting from four types of federal and state regulations could not 

be used to meet rate of progress. These four types of programs are as follows: 

(1) Federal Motor Vehicle Control Program (FMVCP) tailpipe and evaporative standards issued 

in January 1, 1990; 

(2) Federal regulations (55 Fed Reg. 23666, June 11, 1990) limit the Reid Vapor Pressure 

(RVP) of gasoline in ozone nonattainment areas; 

(3) State regulations correcting deficiencies in reasonably available control technology rules 

(4) State regulations establishing or correcting inspection and maintenance (I/M) programs for 

on-road vehicles. 

 

The basic procedures of developing target levels for the 15% Plan are describe in EPA’s guidance, 

Adjusted Base Year Emissions Inventory and the 1996 Target for the 15% Rate of Progress Plans. 

 

5.2 GUIDANCE FOR CALCULATING REASONABLE FURTHER 

PROGRESS (RFP) EMISSION TARGET LEVELS 

The Clean Air Act Amendments (CAAA) of 1990 provide the primary guidance for calculating the 

VOC and NOx target levels used in a region’s RFP plans. In November 2005 as part of its final 

implementation rule for the 8-hour ozone standard, EPA issued guidance to assist the states in RFP 

development. 

 

The guidance that applies to the metropolitan Baltimore area is guidance for previously severe 1-

hour ozone nonattainment areas with an approved 15% RFP plan for the period 1990-1996. Since 

the Baltimore region is a former severe 1-hour ozone nonattainment area and has an approved 15% 

RFP plan for the above period, “Method 2” of the guidance applies to the region.20 The region is 

required to reduce emissions by 15% from 2002-2008 to demonstrate RFP, according to Method 2. 

 

EPA’s guidance (Method 2) states that the target level of VOC and NOx emissions in 2008 needed 

to meet the 2008 RFP requirement is any combination of VOC and NOx reductions from the 

adjusted base year 2002 inventories (base year 2002 emissions minus non-creditable emissions 

reduction occurring between 2002 and 2008) that total 15 percent. For example, the target level of 

VOC emissions in 2008 could be a 10 percent reduction from the adjusted base year 2002 VOC 

inventory and a 5 percent reduction from the adjusted NOx inventory. The actual projected 2008 

VOC and NOx inventories for all sources with all control measures in place and including projected 

2008 growth in activity must be at or lower than the target levels of VOC and NOx emissions. 

This section briefly summarizes the requirements and procedures for calculating the target emission 

levels required for a RFP demonstration. RFP demonstrations build upon each other, starting from 

the base year of 2002. 

20 “Appendix A to Preamble—Methods to Account for Non-Creditable Reductions When Calculating ROP Targets for 

the 2008 and Later ROP Milestone Years,” in Final Rule to Implement the 8-Hour Ozone National Ambient Air Quality 

Standard, Federal Register, Vol 70, No. 228, Nov.29, 2005. 
5.2.1 2008 VOC and NOx Target Levels 

EPA’s Final Rule To Implement the 8-Hour Ozone National Ambient Air Quality Standard – Phase 

II mandates that to meet the reasonable further progress requirement, the Baltimore, MD ozone 

nonattainment area needs to reduce its emissions by 15% between 2002 and 2008 using either 

reductions in VOC or NOx or any combination of the two. The Baltimore region is able to 

demonstrate reasonable further progress for the period 2002-2008. 

 

The target levels for 2008 reasonable further progress plans are calculated according to the EPA’s 

final rule mentioned above. The general formula for calculation of 2008 target levels is as follows: 

 Equation 5-1 

Target

Level 2008

= RFP base year

emissions ‐ 

reductions required to meet

the reasonable further

progress requirement

‐ 

non‐creditable

emissions reduction

between 2002 and 2008

Calculation of 2008 Target Levels 

 

Equation 5-2 gives the general formula for calculating post-1996 target levels. Since the region has 

chosen to demonstrate the 2008 reasonable further progress using 8% VOC reduction, the 2008 

VOC target level becomes: 

Equation 5-2 

2008 VOC Target

Level = 2002 RFP Base‐Year emissions ‐ 8.0% VOCReduction ‐

non‐creditable

emissions reduction

between 2002 and 2008

Equation 5-3 

2008 NOx Target

Level = 2002 RFP Base‐Year emissions ‐ 7.0% NOxReduction ‐

non‐creditable

emissions reduction

between 2002 and 2008

Step 1: Develop 2002 Base Year Inventories and 2002 Reasonable Further Progress Base 

Year Inventories 

 

The 2002 Base-Year Inventory is published in a separate document, "2002 Base Year Emissions 

Inventory & QA/QC Plan Maryland," (June 15, 2006). This document was submitted to EPA 

Region III. The document was prepared by the Maryland Department of the Environment and 

remains intact to fulfill the SIP inventory requirement of the CAA. It is available for inspection at 

the Maryland Department of the Environment, Air and Radiation Management Administration, 

1800 Washington Boulevard, Suite 730, Baltimore, Maryland 21230. 

Baltimore Serious Area 8-Hour Ozone SIP Page 42
The RFP base-year inventory includes only anthropogenic emissions generated within the 

Metropolitan Baltimore Nonattainment Area and is required to utilize the most recent EPA models 

and methods when estimating emissions. As such, the 2002 RFP inventory uses the MOVES model 

to estimate on-road mobile emissions and the NONROAD model (version 2008) to estimate the 

non-road mobile emissions. The reasonable further progress base year VOC and NOx emissions are 

presented in Table 5-1. 

Table 5-1: 

2002 Reasonable Further Progress Base-Year Inventory 

(Ozone Season tons per day) 

Source VOC NOx 

Point 13.88 111.89 

Area 116.81 8.18 

Non-Road 59.61 49.18 

On-Road 72.48 202.22 

TOTAL 262.77 371.47 

Note: Small discrepancies may result due to rounding 

 

Step 2: Develop 2002 and 2008 Reasonable Further Progress Adjusted Year Inventories 

 

According to the 1990 CAAA, reductions necessary to meet the reasonable further progress 

requirement must be calculated from an emissions baseline that excludes the effects of the noncreditable Federal Motor Vehicle Control Program (FMVCP) and Reid Vapor Pressure (RVP) 

programs described in Section 5.1.1. Therefore the 2002 baseline must be adjusted by subtracting 

the VOC and NOx reductions that result from these two programs between 2002 and 2008. The 

resulting inventory is referred to as the 2002 Adjusted Base Year Inventory. 

 

In order to calculate the non-creditable emissions reductions, which occur between 2002 and 2008, 

the following two mobile inventories are needed: 

 

1) 2002 Reasonable Further Progress Adjusted-Year Inventory 

2) 2008 Reasonable Further Progress Adjusted-Year Inventory 

 

Both of these mobile inventories were created using the inputs, listed below, with the only 

difference between the two inventories being the model year. Inventory #1 and #2 were created for 

2002 and 2008, respectively. 

 

a) 1990 I/M Program 

b) RVP = 7.8 psi (RVP required according to June 1990 fuel RVP regulations)21 

 

21 The 1990 Phase II regulations specify 7.8 psi as the maximum RVP of gasoline being sold in the Baltimore, DC-MDVA ozone nonattainment area in 1992.

Baltimore Serious Area 8-Hour Ozone SIP Page 43
c) No Post-1990 Clean Air Act Measures 

d) 2002 Vehicle Activity Inputs 

e) 2002 Vehicle Miles Traveled (VMT) 

The on-road mobile input files are included in Appendix E. Tables 5-2 & 5-3 show RFP adjustedyear inventories for 2002 and 2008, respectively. 

Table 5-2: 

2002 Reasonable Further Progress Adjusted-Year Inventory 

(Ozone Season tons per day) 

Source VOC NOx 

Point 13.88 111.88 

Area 116.81 8.18 

Non-Road 70.22 40.96 

On-Road 111.14 287.69 

TOTAL 312.05 448.71 

Note: Small discrepancies may result due to rounding 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 44
Table 5-3: 

2008 Reasonable Further Progress Adjusted-Year Inventory 

(Ozone Season tons per day) 

Source VOC NOx 

Point 13.88 111.88 

Area 116.81 8.18 

Non-Road 70.22 40.96 

On-Road 107.05 285.91 

TOTAL 307.96 446.93 

Note: Small discrepancies may result due to rounding 

 

 Step 3: Non-creditable Emissions Reductions 

The non-creditable emissions reductions that occur in the absence of any post-1990 CAA measures 

during a reasonable further progress period can be determined by taking the difference between the 

RFP adjusted-year inventories for the relevant milestone years. For VOC and NOx, the relevant 

milestone years are 2002 and 2008. 

Equation 5-4 

Non‐creditable

Emissions Reductions = 2002 RFP AdjustedYear Inventory ‐  2008 RFP Adjusted

Year Inventory

Table 5-4: 

Calculation of Non-creditable Emissions Reductions 

(Ozone Season tons per day) 

Description VOC NOx

2002 Adjusted Year Inventory (a) 111.14 287.69 

2008 Adjusted Year Inventory (b) 107.05 285.91 

Non-creditable Emissions Reduction (a-b) 4.09 1.78 

Step 4: Calculation of 2008 Target Levels 

 

The VOC and NOx target levels for 2008 are calculated in Table 5-5 below: 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 45
Table 5-5: 

Calculation of VOC and NOx Target Levels for 2008 

(Ozone Season tons per day) 

 Description Formula VOC NOx 

A 2002 Base Year Inventory 485.97 371.47

B Biogenic Emissions 223.20 0.00

C 2002 Rate-of Progress Base Year Inventory A - B 262.77 371.47

D FMVCP/RVP Reductions Between 2002 and 2008 4.08 1.78

E 2002 Adjusted Base Year Inventory Calculated Relative to 2008 C - D 258.69 369.69

F Reduction Ratio 0.0800 0.0700

G Emissions Reductions Required Between 2002 and 2008 E * F 20.70 25.88

H Target Level for 2008 [TL(2008)] C - D - G 238.00 343.81

 

5.3 COMPLIANCE WITH 2008 REASONABLE FURTHER PROGRESS 

REQUIREMENTS 

 

In order to demonstrate reasonable further progress for the period 2002-2008, the Baltimore region 

must show that expected emissions in 2008 are equal to or less than the 2008 target levels presented 

in Table 5-5. 

 

The 2008 controlled inventories are inventories of all anthropogenic VOC and NOx emissions 

expected to occur in the Baltimore Nonattainment Area during 2008. The 2008 inventories were 

developed as described in Chapter 4 and are displayed in Table 4-5. As summarized in Table 5-6, 

the 2008 controlled VOC and NOx inventories are less than the 2008 target inventories. Table 5-6 

demonstrates that the Baltimore region fulfills the 2002-2008 reasonable further progress 

requirements. 

 

Table 5-6: 

Baltimore Nonattainment Area 

Comparison of 2008 Controlled and Target Inventories 

Ozone Season Daily Emissions (tons per day) 

Description VOC NOx

2008 Target Levels 238.00 343.81 

2008 Controlled Emissions 217.96 299.62 

Baltimore Serious Area 8-Hour Ozone SIP Page 46
References 

 

U.S. EPA, “Guidance on the Adjusted Base Year Emissions Inventory and the 1996 Target for the 

15% Rate of Progress Plans” 

 

U.S. EPA, “Guidance on the Post-1996 Reasonable Further Progress Plan and the Attainment 

Demonstration,” February 18, 1994. 

 

U.S. EPA, “NOx Substitution Guidance,” December 1993. 

Baltimore Serious Area 8-Hour Ozone SIP Page 47
6.0 2011 REASONABLE FURTHER PROGRESS REQUIREMENTS 

6.1 INTRODUCTION 

 

In addition to the 2002-2008 reasonable further progress (RFP) demonstration contained in Chapter 

5, the Baltimore region must also demonstrate RFP for the period 2008-2011. In order to 

demonstrate RFP, a region must show that its expected emissions, termed “controlled inventories,” 

of NOx and VOC will be less than or equal to the target levels set for the end of the RFP period, or 

“milestone year”. By re-classifying as a “serious” ozone nonattainment area, the Baltimore region is 

required to establish target levels that reduce VOC and NOx emissions by 3 percent per year (or 9% 

total) over the 2008 to 2011 period. For the RFP period 2008-2011, the target levels of emissions 

are the maximum quantity of anthropogenic emissions permissible during the 2011 milestone year. 

This section describes the methodology used to establish the regional target inventories and 

controlled inventories for 2011. Because the expected NOx and VOC emissions will be less than the 

target levels, the Baltimore region will meet the RFP requirements by the January 1, 2012 deadline. 

6.2 GUIDANCE FOR CALCULATING REASONABLE FURTHER 

PROGRESS (RFP) EMISSION TARGET LEVELS 

 

The guidance and methods used to calculate the 2011 target levels are the same as for the 2008 

target levels; however, the starting point is the 2008 target levels instead of the 2002 Base Year 

Inventory. 

6.2.1 2011 VOC and NOx Target Levels 

EPA’s Final Rule To Implement the 8-Hour Ozone National Ambient Air Quality Standard – Phase 

II mandates that to meet the reasonable further progress requirement, the Baltimore ozone 

nonattainment area needs to reduce its emissions by 9% between 2008 and 2011 using either 

reduction in VOC or NOx or any combination of the two. The Baltimore region is able to 

demonstrate reasonable further progress for the period 2008-2011. 

 

The target levels for 2011 reasonable further progress plans are calculated according to the EPA’s 

final rule mentioned above. The general formula for calculation of 2011 target levels is as follows: 

Equation 6-1 

Target

Level 2011

= Target Level

2008

‐  Reductions Required to

meet the RFP (2008 – 2011) ‐ 

non‐creditable

emissions reduction

between 2008 and 2011

Equation 6-1, above, gives the general formula for calculating 2011 target levels. Since the region 

has chosen to demonstrate the 2008 reasonable further progress using a 6% VOC reduction, the 

2011 VOC target level is as shown in Equation 6-2: 

Baltimore Serious Area 8-Hour Ozone SIP Page 48
Equation 6-2 

2011 VOC Target

Level = 2008 VOC  Target Level ‐ 6.0% VOCReduction ‐

non‐creditable

emissions reduction

between 2008 and 2011

Equation 6-3 

2011 NOx Target

Level = 2008 NOXTarget Level ‐ 3.0% NOxReduction ‐

non‐creditable

emissions reduction

between 2008 and 2011

Step 1: Develop 2008 Target Levels for VOC and NOx 

 

The 2008 target levels were developed in accordance with EPA protocols and the methods were 

presented in Chapter 5. 

Step 2: Non-creditable Emissions Reductions 

The non-creditable emissions reductions that occur in the absence of any post-1990 CAA measures 

during a reasonable further progress period can be determined by taking the difference between the 

RFP adjusted-year inventories for the relevant milestone years. For VOC and NOx, the relevant 

milestone years are 2008 and 2011. Note: The non-creditable emissions reductions between two 

RFP years cannot be negative. 

Equation 6-4 

Non‐creditable

Emissions Reductions = 2008 RFP AdjustedYear Inventory ‐  2011 RFP AdjustedYear Inventory

Table 6-1: 

Calculation of Non-creditable Emissions Reductions 

(Ozone Season tons per day) 

Description VOC NOx

Non-creditable Emissions Reduction (2008 – 2011) 0.29 0.00 

Step 3: Calculation of 2011 Target Levels 

 

Following Equations 6-2, 6-3 and 6-4, the VOC and NOx target levels for 2011 are calculated in 

Table 6-2 below: 

Baltimore Serious Area 8-Hour Ozone SIP Page 49
Table 6-2: 

Calculation of VOC and NOx Target Levels for 2011 

(Ozone Season tons per day) 

 Description Formula VOC NOx 

A 2008 Target Level 238.00 343.81

B FMVCP/RVP Reductions Between 2008 and 2011 0.29 0.00

C 2002 Adjusted Base Year Inventory Calculated Relative to 2011 A - B 237.71 343.81

D Reduction Ratio 0.0600 0.0300

E Emissions Reductions Required Between 2008 and 2011 C * D 14.28 10.31

F Target Level for 2011 [TL(2011)] A - B - E 223.72 333.49

6.3 COMPLIANCE WITH 2011 REASONABLE FURTHER PROGRESS 

REQUIREMENTS 

In order to demonstrate reasonable further progress for the period 2008-2011, the Baltimore region 

must show that expected emissions in 2011 are equal to or less than the 2011 target levels presented 

in Table 6-2. 

 

The 2011 controlled inventories are inventories of all anthropogenic VOC and NOx emissions 

expected to occur in the Baltimore Nonattainment Area during 2011. The inventories were 

developed as described in Chapter 4 and are displayed in Table 4-6. As summarized in Table 6-3, 

the 2011 controlled VOC and NOx inventories are less than the 2011 target inventories. Table 6-3 

demonstrates that the Baltimore region fulfills the 2008-2011 reasonable further progress 

requirements. 

 

Table 6-3: 

Baltimore Nonattainment Area 

Comparison of 2011 Controlled and Target Inventories 

Ozone Season Daily Emissions (tons per day) 

Description VOC NOx

2011 Target Levels 223.72 333.49 

2011 Controlled Emissions 205.65 246.48 

Baltimore Serious Area 8-Hour Ozone SIP Page 50
7.0 2012 REASONABLE FURTHER PROGRESS REQUIREMENTS 

7.1 INTRODUCTION 

 

In addition to the 2008-2011 reasonable further progress (RFP) demonstration contained in Chapter 

6, the Baltimore region must also demonstrate reasonable further progress for the period 2011-2012. 

In order to demonstrate reasonable further progress, a region must show that its expected emissions, 

termed “controlled inventories,” of NOx and VOC will be less than or equal to the target levels set 

for the end of the reasonable further progress period, or “milestone year”. By re-classifying as a 

“serious” ozone nonattainment area, the Baltimore region is required to establish target levels that 

reduce VOC and NOx emissions by 3 percent per year (or 3% total) over the 2011 to 2012 period. 

For the reasonable further progress period 2011-2012, the target levels of emissions are the 

maximum quantity of anthropogenic emissions permissible during the 2012 milestone year. This 

section describes the methodology used to establish the regional target inventories and controlled 

inventories for 2012. Because the expected NOx and VOC emissions will be less than the target 

levels, the Baltimore region will meet the reasonable further progress requirements by the January 

1, 2013 deadline. 

7.2 GUIDANCE FOR CALCULATING REASONABLE FURTHER 

PROGRESS (RFP) EMISSION TARGET LEVELS 

 

The guidance and methods used to calculate the 2012 target levels are the same as the 2008 and 

2011 target levels, however the starting point is the 2011 target level. 

7.2.1 2012 VOC and NOx Target Levels 

EPA’s Final Rule To Implement the 8-Hour Ozone National Ambient Air Quality Standard – Phase 

II mandates that to meet the reasonable further progress requirement, the Baltimore ozone 

nonattainment area needs to reduce its emissions by 3 between 2011 and 2012 using reductions in 

either VOC or NOx or any combination of the two. The Baltimore region is able to demonstrate 

reasonable further progress for the period 2011-2012. 

 

The target levels for 2012 reasonable further progress plans are calculated according to the EPA’s 

final rule mentioned above. The general formula for calculation of 2012 target levels is as shown in 

Equation 7-1: 

 

Equation 7-1 

Target

Level 2012

= Target Level

2011

‐  Reductions Required to

meet the RFP (2011 – 2012) ‐ 

non‐creditable

emissions reduction

between 2011 and 2012

Equation 7-1, above, gives the general formula for calculating 2012 target levels. Since the region 

has chosen to demonstrate the 2012 reasonable further progress using a 1.5% VOC reduction, the 

2012 VOC target level is as shown in Equation 7-2. 

Baltimore Serious Area 8-Hour Ozone SIP Page 51
Equation 7-2 

2012 VOC Target

Level = 2011 VOC  Target Level ‐ 1.5% VOCReduction ‐

non‐creditable

emissions reduction

between 2011 and 2012

Equation 7-3 

2012 NOx Target

Level = 2011 NOXTarget Level ‐ 1.5% NOxReduction ‐

non‐creditable

emissions reduction

between 2011 and 2012

Step 1: Develop 2011 Target Levels for VOC and NOx 

 

The 2011 target levels were developed in accordance with EPA protocols and the methods were 

presented in Chapter 6. 

Step 2: Non-creditable Emissions Reductions 

The non-creditable emissions reductions that occur in absence of any post-1990 CAA measures 

during a reasonable further progress period can be determined by taking the difference between the 

RFP adjusted-year inventories for the relevant milestone years. For VOC and NOx, the relevant 

milestone years are 2011 and 2012. The non-creditable emissions reductions between two RFP 

years cannot be negative. 

Equation 7-4 

Non‐creditable

Emissions Reductions = 2011 RFP AdjustedYear Inventory ‐  2012 RFP Adjusted

Year Inventory

Table 7-1: 

Calculation of Non-creditable Emissions Reductions 

(Ozone Season tons per day) 

Description VOC NOx

Non-creditable Emissions Reduction (2008 – 2011) 0.00 0.18 

Step 3: Calculation of 2012 Target Levels 

 

Following Equations 7-2, 7-3 and 7-4, the VOC and NOx target levels for 2012 are calculated in 

Table 7-2 below: 

Baltimore Serious Area 8-Hour Ozone SIP Page 52
 

Table 7-2: 

Calculation of VOC and NOx Target Levels for 2012 

(Ozone Season tons per day) 

 Description Formula VOC NOx 

A 2011 Target Level 223.73 333.49

B FMVCP/RVP Reductions Between 2011 and 2012 0.00 0.18

C 2002 Adjusted Base Year Inventory Calculated Relative to 2012 B - A 223.73 333.32

D Reduction Ratio 0.0150 0.0150

E Emissions Reductions Required Between 2011 and 2012 C * D 3.36 5.00

F Target Level for 2012 [TL(2012)] A - B - E 220.38 328.49

7.3 COMPLIANCE WITH 2012 REASONABLE FURTHER PROGRESS 

REQUIREMENTS 

In order to demonstrate reasonable further progress for the period 2011-2012, the Baltimore region 

must show that expected emissions in 2012 are equal to or less than the 2012 target levels presented 

in Table 7-2. 

 

The 2012 controlled inventories are inventories of all anthropogenic VOC and NOx emissions 

expected to occur in the Baltimore Nonattainment Area during 2012. The inventories were 

developed as described in Chapter 4 and are displayed in Table 4-7. As summarized in Table 7-3, 

the 2012 controlled VOC and NOx inventories are less than the 2012 target inventories. Table 7-3 

demonstrates that the Baltimore region fulfills the 2011-2012 reasonable further progress 

requirements. 

 

Table 7-3: 

Baltimore Nonattainment Area 

Comparison of 2012 Controlled and Target Inventories 

Ozone Season Daily Emissions (tons per day) 

Description VOC NOx

2012 Target Levels 220.38 328.49 

2012 Controlled Emissions 199.90 232.88 

Baltimore Serious Area 8-Hour Ozone SIP Page 53
8.0 CONTROL MEASURES 

This chapter is divided into three sections. Section 8.1 identifies the control measures that were part 

of the 1-Hour Ozone SIP for the Baltimore Nonattainment Area. These regulations/control 

measures continue to be in existence and continue to reduce emissions in the region. All of the 

emission reductions from the measures identified in Section 8.1 were part of the baseline emissions 

inventory for the Baltimore Nonattainment Area. 

Section 8.2 of this chapter identifies measures implemented after 2002 that were not part of the 

baseline inventory and are giving specific emission reductions to the region’s 8-hour Ozone 

reasonable further progress demonstration. 

Section 8.3 identified voluntary/innovative measures that the Maryland is not taking formal credit 

for in the SIP. These measures are not commitments to programs but present information on 

programs that are directionally correct and could provide ozone benefits. 

8.1 1-HOUR OZONE CONTROL MEASURES 

8.1.1 On-Road Mobile Measures 

Enhanced Vehicle Inspection and Maintenance (Enhanced I/M) 

The Clean Air Act (CAA or “the Act”) requires enhanced motor vehicle inspection and 

maintenance (I/M) programs in serious, severe, and extreme ozone nonattainment areas and 

Metropolitan Statistical Area (MSA)/Consolidated Metropolitan Statistical Area (CMSA) portions 

of the OTR with urbanized populations over 200,000. In Maryland, this required an enhanced I/M 

program in the eight jurisdictions operating a basic I/M program as well as six new jurisdictions, for 

a total of 14 of the 23 jurisdictions in the state. Tailpipe emissions are measured over a transient 

driving cycle conducted on a dynamometer, which provides a much better indication of actual onroad vehicle performance than the existing idle test. 

 

Tier I Vehicle Emission Standards and New Federal Evaporative Test Procedures 

The Act requires a new and cleaner set of federal motor vehicle emissions standards (Tier I 

standards) beginning with model year 1994. The Act also requires a uniform level of evaporative 

Baltimore Serious Area 8-Hour Ozone SIP Page 54
emission controls which are more stringent than most evaporative controls used in existing vehicles. 

These federally implemented programs affect light duty vehicles and trucks. 

 

Reformulated Gasoline in On-road Vehicles 

All gasoline-powered vehicles are affected by this control measure. Vehicle refueling emissions at 

service stations are also reduced. In addition, emissions from gasoline powered nonroad vehicles 

and equipment are reduced by this control strategy. Since January 1995, only gasoline that the EPA 

has certified as reformulated may be sold to consumers in the nine worst ozone nonattainment areas 

with populations exceeding 250,000. 

Tier 2 Vehicle Emission Standards 

On December 21, 1999, the EPA announced new regulations affecting tailpipe emissions standards 

for the production of new cars and light trucks weighing up to 8,500 pounds. Commonly referred to 

as “Tier 2,” these standards take effect beginning in 2004. The emissions reduction benefits of this 

Tier 2 program for the Maryland region are be significant, including passenger cars that are 77 

percent cleaner than those on the road today. Light-duty trucks, such as Sport Utility Vehicles 

(SUVs), which are subject to standards that are less protective than those for cars, would be as much 

as 95 percent cleaner under the new standards. In effect, the rule forces SUVs and light trucks to 

meet the same tailpipe emission standards as cars. 

As part of the new tailpipe standard, the EPA also announced standards for lower sulfur in gasoline. 

The lower sulfur standards are necessary to enable passenger vehicles to meet Tier 2 emission 

standards. 

National Low Emission Vehicle Program 

The National Low Emission Vehicle Program (National LEV) program is a vehicle technology 

program resulting in the production of light duty vehicles and light-duty trucks with significantly 

lower tailpipe emissions. The National LEV program is applicable to 1999 and later model-year 

vehicles sold in the Ozone Transport Region (OTR) and 2001 and later model-year vehicles sold 

throughout the United States. The National LEV program was developed through an 

unprecedented, cooperative, voluntary effort by the northeastern states, auto manufacturers, 

environmentalists, fuel providers, U.S. EPA and other interested parties. National LEV vehicles are 

70 percent cleaner than 1998 models. The National LEV program results in substantial reductions in 

volatile organic compounds (VOCs) and oxides of nitrogen (NOx), which contribute to unhealthy 

levels of smog in many areas across the country. 

Baltimore Serious Area 8-Hour Ozone SIP Page 55
Federal Heavy-Duty Diesel Engine Rule 

EPA’s heavy-duty diesel engine (HDDE) rule addresses diesel vehicles weighing more than 8,500 

pounds. These standards take effect in 2007 and reduce emissions from new HDDEs by 95%. In 

order to achieve the new standards, ultra-low sulfur diesel fuel will also be needed. 

Stage II and New Vehicle On-Board Vapor Recovery Systems 

These measures required the following: (1) installation of Stage II vapor recovery nozzles at 

gasoline pumps and (2) the installation of onboard refueling emissions (onboard refueling vapor 

recovery, or “ORVR”) controls for new passenger cars and light trucks beginning in the 1998 model 

year. Maryland adopted Stage II vapor recovery regulations for the Baltimore and Washington 

nonattainment areas and Cecil County in January of 1993, earlier than required of the Ozone 

Transport Region (OTR). The Stage II vapor recovery regulation requires that the gasoline 

dispensing system be equipped with nozzles that are designed to return the vapors, through a vapor 

line, into the gasoline tank. 

8.1.2 Area Source Measures 

VOC Controls in Maryland22

 Automotive and Light-Duty Truck Coating 

 Can Coating 

 Coil Coating 

 Large Appliance Coating 

 Paper, Fabric, Vinyl, and Other Plastic Parts Coating 

 Control of VOC Emissions from Solid Resin Decorative Surface Manufacturing 

 Metal Furniture Coating 

 Control of VOC Emissions from Cold and Vapor Degreasing 

 Flexographic and Rotogravure Printing 

 Lithographic Printing 

 Dry Cleaning Installations 

 Miscellaneous Metal Coating 

 Aerospace Coating Operations 

 Brake Shoe Coating Operations 

 Control of Volatile Organic Compounds from Structural Steel Coating Operations 

 Manufacture of Synthesized Pharmaceutical Products 

 Paint, Resin and Adhesive Manufacturing and Adhesive Application 

 Control of VOC Equipment Leaks 

 Control of Volatile Organic Compound (VOC) Emissions from Yeast Manufacturing 

 Control of Volatile Organic Compound Emissions from Screen Printing and Digital Imaging 

 

22 See the Code of Maryland Regulations (COMAR) 26.11.10, 26.11.14, and 26.11.19. 

Baltimore Serious Area 8-Hour Ozone SIP Page 56
 Control of Volatile Organic Compounds (VOC) Emissions from Expandable Polystyrene 

Operations 

 Control of Landfill Gas Emissions from Municipal Solid Waste Landfills 

 Control of Volatile Organic Compounds (VOC) Emissions from Commercial Bakery Ovens 

 Control of Volatile Organic Compounds (VOC) from Vinegar Generators 

 Control of VOC Emissions from Vehicle Refinishing 

 Control of VOC Emissions from Leather Coating 

 Control of Volatile Organic Compounds from Explosives and Propellant Manufacturing 

 Control of Volatile Organic Compound Emissions from Reinforced Plastic Manufacturing 

 Control of Volatile Organic Compounds from Marine Vessel Coating Operations 

 Control of Volatile Organic Compounds from Bread and Snack Food Drying Operations 

 Control of Volatile Organic Compounds from Distilled Facilities 

 Control of Volatile Organic Compounds from Organic Chemical Production 

 Iron and Steel Production Installations 

 Control of Kraft Pulp Mill Emissions 

Municipal Landfills 

A municipal solid waste landfill is a disposal facility where household waste is placed and 

periodically covered with inert material. Landfill gases are produced from the decomposition and 

chemical reactions of the refuse in the landfill. They consist primarily of methane and carbon 

dioxide, with volatile organic compounds making up less than one percent of the total emissions. 

The control strategy for this source category is based upon federal rules. 

Burning Ban 

Open burning is primarily used for the disposal of brush, trees, and 

yard waste and as a method of land clearing by both developers and 

individual citizens. Emissions from open burning include oxides of 

nitrogen, hydrocarbons, carbon dioxide (CO2), carbon monoxide 

(CO) and other toxic compounds. Emissions levels from open 

burning are high due to the inefficient and uncontrolled manner in 

which the material is burned. The Department adopted a regulation that prohibits open burning 

during the peak ozone period (June to August). There are exemptions for agricultural burning, fire 

training and recreational activities. 

Surface Cleaning/Degreasing 

Cold degreasing is an operation that uses solvents and other materials to remove oils and grease 

from metal parts including automotive parts, machined products and fabricated metal components. 

MDE adopted regulations in 1995 to require small degreasing operations such as gasoline stations, 

autobody paint shops and machine shops to use less polluting degreasing solvents in serious and 

Baltimore Serious Area 8-Hour Ozone SIP Page 57
severe ozone nonattainment areas. Also, solvent baths and rags soaked with solvents must be 

covered under this regulation. 

Architectural and Industrial Maintenance Coatings 

Architectural and industrial maintenance coatings are field-applied coatings used by industry, 

contractors, and homeowners to coat houses, buildings, highway surfaces, and industrial equipment 

for decorative or protective purposes. VOC emissions result from the evaporation of solvents from 

the coatings during application and drying. A federal measure requires reformulation of 

architectural and industrial maintenance coatings. The users of these coatings are small and 

widespread, making the use of add-on control devices technically and economically infeasible. 

Commercial and Consumer Products 

Consumer and commercial products are items sold to retail customers for household, personal or 

automotive use, along with the products marketed by wholesale distributors for use in institutional 

or commercial settings such as beauty shops, schools, and hospitals. VOC emissions result from the 

evaporation of solvent contents in the products or solvents used as propellants. This measure 

requires the reformulation of certain consumer products to reduce their VOC content. Product 

reformulation can be accomplished by substituting water, other non-VOC ingredients, or low-VOC 

solvents for VOCs in the product. 

Automobile Refinishing 

Automobile refinishing is the repainting of worn or damaged automobiles, light trucks and other 

vehicles. Volatile organic compound emissions result from the evaporation of solvents from the 

coatings during application, drying and clean up techniques. This measure, based in state regulation, 

requires large and small autobody refinishing operations to use low VOC content materials in the 

refinishing process and cleanup, and to use efficient spray guns to control application. The 

Department adopted regulations in 1995 requiring the use of reformulated coatings. 

Screen Printing 

A screen-printing process is used to apply printing or an image to virtually any substrate. In the 

screen-printing operation, ink is distributed through a porous screen mesh to which a stencil may 

have been applied to define an image to be printed on a substrate. VOC emissions result from the 

evaporation of ink solvents and from the use of solvents for cleaning. The major source of VOC 

emissions is the printing process. This measure requires smaller printers to use water based and/or 

low VOC materials to reduce VOC emissions. Because the users of these coatings are relatively 

small, requiring the use of add-on control devices is technically and economically infeasible. 

Reductions in VOC emissions were obtained through the use of ink reformulation, process printing 

modification, and material substitution for cleaning operations. This regulation became effective on 

June 5, 1995. 

Baltimore Serious Area 8-Hour Ozone SIP Page 58
Graphic Arts – Lithographic Printing 

This source category consists of numerous small sheet-fed printers that perform non-continuous 

printing, and web printers that print on a continuous web or roll. Heat-set web printers use drying 

ovens to force dry the printed matter. Web printing sources perform high volume printing on paper 

or paperboard. VOC emissions are caused by evaporation of the ink solvents, alcohol in the 

fountain or dampening solution, and equipment wash solvents. These VOC discharges may also 

cause visible emissions and nuisance odors. MDE adopted a regulation in 1995 to require printers to 

use control devices and/or low VOC materials to reduce VOC emissions. 

Graphic Arts – Flexographic and Rotogravure Printing 

This source category consists of numerous small flexographic or rotogravure printers that perform 

non-continuous sheet fed printing and continuous web or roll printing. MDE adopted a printing 

regulation in 1987 that requires smaller printers to use control devices and/or low VOC materials to 

reduce VOC emissions. VOC emissions are caused almost entirely by evaporation of the ink 

solvents. Although several control devices were evaluated over the years for rotogravure and 

flexographic web printers, a catalytic oxidizer has proven to be most successful. A typical oxidizer 

yields 96-98 percent destruction of VOC. Most sources were in compliance with all requirements 

by early 1992. 

8.1.3 Non-Road Measures 

Nonroad Small Gasoline Engines 

This measure requires small gasoline-powered engine equipment, such as lawn and garden 

equipment, manufactured after August 1, 1996 to meet federal emissions standards. Small gasolinepowered engine equipment includes, for example, lawn mowers, trimmers, generators, and 

compressors. These measures apply to equipment with engines of less than 25 horsepower. VOC 

emissions result from combustion and evaporation of gasoline used to power this equipment. 

Non-Road Diesel Engines Tier I and Tier II 

This measure takes credit for NOx emissions reductions from emissions standards promulgated by 

the EPA for non-road, compression-ignition (i.e., diesel-powered) utility engines. The measure 

affects diesel-powered (or other compression-ignition) heavy-duty farm, construction equipment, 

industrial equipment, etc., rated at or above 37 kilowatts (37 kilowatts is approximately equal to 50 

horsepower). Heavy-duty farm and construction equipment includes asphalt pavers, rollers, 

scrapers, rubber-tired dozers, agricultural tractors, combines, balers, and harvesters. This measure 

applies to all compression-ignition engines except engines used in aircraft, marine vessels, 

Baltimore Serious Area 8-Hour Ozone SIP Page 59
locomotives and underground mining activity. NOx emissions result from combustion of diesel 

fuel used to power this equipment. 

Marine Engine Standards 

Of the nonroad sources studied by EPA, gasoline marine engines were found to be one of the largest 

contributors of hydrocarbon (HC) emissions, 30% of the nationwide nonroad total. This measure 

controls exhaust emissions from new spark-ignition (SI) gasoline marine engines, including 

outboard engines, personal watercraft engines, and jet boat engines. 

Emissions standards for large spark ignition engines 

This EPA measure controls VOC and NOx emissions from several groups of previously unregulated 

nonroad engines, including large industrial spark-ignition engines, recreational vehicles, and diesel 

marine engines. The emission standards apply to all new engines sold in the United States and any 

imported engines manufactured after these standards begin. Controls on the category of large 

industrial spark-ignition engines are first required in 2004. Large industrial spark-ignition engines 

are those rated over 19 kW used in a variety of commercial applications; most use liquefied 

petroleum gas, with others operating on gasoline or natural gas. Controls on the other engine 

categories are required beginning in years after 2005. 

Reformulated gasoline use in non-road motor vehicles and equipment 

This federally mandated measure requires the use of lower polluting "reformulated" gasoline in the 

Baltimore Nonattainment Area. The measure involves taking credit for emissions reductions 

resulting from the use of the federally reformulated gasoline in non-road mobile sources. 

Nonattainment areas classified as severe were required to opt in on the delivery of reformulated 

gasoline. This measure affects the various non-road mobile sources that burn gasoline, such as 

small gasoline-powered engine equipment including lawn mowers, trimmers, generators, and 

compressors. VOC emissions result from combustion and evaporation of gasoline used to power 

this equipment. 

Railroad Engine Standards 

This measure establishes emission standards for oxides of nitrogen, hydrocarbons, carbon 

monoxide, particulate matter, and smoke for newly manufactured and remanufactured dieselpowered locomotives and locomotive engines, which were previously unregulated. This regulation 

took effect in 2000 and affects railroad manufacturers and locomotive re-manufacturers. It involves 

adoption of three separate sets of emission standards with the applicability dependent on the date a 

locomotive is first manufactured. 

Baltimore Serious Area 8-Hour Ozone SIP Page 60
8.1.4 Point Source Measures 

Expandable Polystyrene Products 

 

These sources use expandable polystyrene beads that contain pentane, a VOC, to manufacture foam 

products such as foam cups, board insulation, and custom shapes. VOC emissions typically occur 

during storage and pre-expansion of the beads, during manufacturing, and during "aging" when the 

blowing agent (pentane) slowly diffuses from the foam before shipping. This control measure 

requires Reasonably Available Control Technologies (RACT) to be installed at operations that 

manufacture foam cups, foam insulation and other foam products. The regulation became effective 

in July 1995. 

Yeast Manufacturing 

Yeast is produced using an aerated fermentation process under controlled conditions. In June 1995, 

MDE required RACT to be installed at two yeast-manufacturing operations in the Baltimore 

Nonattainment Area. The regulation results in an overall emission reduction of approximately 60 to 

70 percent from the 1990 baseline by requiring affected sources to meet specific VOC emission 

standards. 

Commercial Bakery Ovens 

This measure requires commercial bakeries using yeast to leaven bread and bread products to install 

RACT. Commercial bakeries generate VOC emissions from the fermentation and baking processes 

used to produce yeast-raised baked goods. These emissions are primarily ethanol. The regulation 

requires control equipment dependent upon thresholds that are based on cost effectiveness criteria. 

Federal Air Toxics 

This measure covers sources that are required to comply with federal air toxics requirements. The 

Department has delegation to implement federal air toxics rules that will achieve VOC emissions 

reductions. Federal rules that may achieve such reductions include the following: federal 

NESHAPs for vinyl chloride production plants, benzene emissions from equipment leaks, benzene 

storage vessels, coke by-product recovery plants, benzene transfer operations, and benzene waste 

operations; and the EPA Maximum Achievable Control Technology (MACT) program. 

Enhanced Rule Compliance 

Enhanced Rule Compliance or rule effectiveness (RE) improvement refers to an improvement in the 

implementation of and compliance with a regulation. These RE improvements may take several 

forms, ranging from more frequent and in-depth training of inspectors to larger fines for sources 

that do not comply with a given rule. 

Baltimore Serious Area 8-Hour Ozone SIP Page 61
State Air Toxics 

This measure addresses stationary sources that are covered by Maryland's air toxics regulations that 

have achieved VOC reductions above and beyond current federally enforceable limits. In general, 

Maryland's air toxics regulations cover any source required to obtain a permit to construct or 

annually renewed state permit to operate. The Department adopted the air toxics regulations in 

1988. 

NOx RACT -- Reasonably Available Control Technology 

This measure requires control of nitrogen oxides (NOx) emissions by installing RACT. NOx 

RACT will apply to utility, industrial and commercial fuel burning equipment and combustion 

installations. The regulation established cost-effective controls on all installations located at major 

NOx sources. This first phase of stationary source NOx reductions resulted in an approximate 22% 

reduction in NOx emissions. 

NOx Phase II/Phase III Ozone Transport Commission (OTC)/NOx Budget Rule (Phase 

II) and NOx SIP Call (Phase III) 

In 1994, the OTC member states signed a major agreement to reduce NOx emissions from power 

plants and other major stationary sources of pollution throughout the Northeast and Mid-Atlantic 

states. The agreement recognized that further reductions in NOx emissions are needed to enable the 

entire Ozone Transport Region (OTR) to meet the NAAQS. The Department adopted a “NOx 

Budget” rule to require a second phase of stationary source NOx reductions as part of this 

regulatory initiative. This regulation requires large stationary sources to reduce summertime NOx 

emissions by approximately 65% from 1990 levels. The regulation also includes provisions 

allowing sources to comply by trading “allowances.” This regulation requires affected sources to 

have met these requirements by May 2000. 

In late 1998, the U.S. EPA adopted its “NOx SIP Call” to reduce ozone transport in the Eastern 

United States. This regional NOx reduction program requires 22 states, including Maryland, to 

submit regulations and a revision to State Implementation Plans (SIPs) to further reduce NOx 

emissions. Maryland’s Phase III regulations achieve approximately 23% additional reductions from 

large stationary sources such as power plants, cement kilns and large industrial boilers. The 

regulations require affected sources to add specific control equipment, reduce emissions, or trade to 

meet the allowable amount ("cap") of seasonal NOx emissions by 2003. 

8.2 8-HOUR OZONE CONTROL MEASURES 

The following measures have been implemented in Maryland since 2002, the baseline emissions 

inventory year for 8-Hour Ozone. These measures were not part of the baseline emissions 

inventory for the 8-Hour Ozone SIP, and emission reductions from these measures were forecasted 

for 2008, 2011, and 2012 (reasonable further progress calculation) and 2012 (attainment inventory) 

for use in the reasonable further progress calculations for the Baltimore Nonattainment Area as well 

as the attainment modeling for the region. A summary of the control measures and their benefits is 

Baltimore Serious Area 8-Hour Ozone SIP Page 62
presented in Table 8-1 below. The benefits below summarize the emission credits available from the 

listed measures based on the difference between a controlled and uncontrolled inventory, each year, 

for each pollutant. 

Table 8-1: Summary of Emissions Credits Available from Control Measures 

   2008 2011 2012

Control Measure VOC NOx VOC NOx VOC NOx

Total Mobile

(Includes Enhanced I/M,  Tier I,  

Reform Gas, LEV, and HDDE)

52.86 158.43 62.23 181.35 66.59 192.33

Stage II/Refuel 0.00 0.00 0.00 0.00 0.00 0.00

OTC ‐ Consumer Products Phase 1 3.70 0.00 3.77 0.00 3.79 0.00

OTC ‐ Consumer Products Phase 2 0.00 0.00 0.46 0.00 0.46 0.00

OTC – AIM 6.03 0.00 6.19 0.00 6.19 0.00

OTC ‐ PFC Phase 1 6.71 0.00 8.31 0.00 8.35 0.00

OTC ‐ PFC Phase 2 0.00 0.00 0.60 0.00 0.60 0.00

OTC ‐ Industrial Adhesives 0.00 0.00 2.63 0.00 2.64 0.00

Open Burning 0.00 0.00 0.00 0.00 0.00 0.00

Nonroad Model 17.85 8.12 26.33 14.55 29.83 17.30

Railroads (Tier 2) 0.00 1.18 0.00 1.58 0.00 1.67

Healthy Air Act (HAA) 0.00 0.00 0.00 31.86 0.00 37.18

Total 87.14 167.73 110.51 229.35 118.45 248.48

8.2.1 The Maryland Healthy Air Act (HAA) 

In April of 2006, the Maryland General Assembly enacted the Maryland Healthy Air Act. The 

Maryland General Assembly record related to the HAA and the final version of the Act itself can be 

found at: 

http://mlis.state.md.us/2006rs/billfile/SB0154.htm 

The MDE Regulations (Code of Maryland Regulations) can be found at: 

http://www.mde.state.md.us/assets/document/CPR_12-26-

06_Emergency_and_Permanent_HAA_Regs_for_AELR.pdf

The HAA requires reductions in nitrogen oxides (NOx), sulfur dioxide (SO2) and mercury 

emissions from large coal burning power plants. The Healthy Air Act also requires that Maryland

become involved in the Regional Greenhouse Gas Initiative (RGGI) which is aimed at reducing 

greenhouse gas emissions. 

The Maryland Department of the Environment has been charged with implementing the HAA 

through regulations. As enacted, these regulations constitute the most sweeping air pollution 

emission reduction measure proposed in Maryland history. 

Baltimore Serious Area 8-Hour Ozone SIP Page 63
Affected Sources 

 

The Healthy Air Act NOx reduction requirements affect the fossil fuel fired electric generating units 

below. Note that only the Ravens Power Holdings, LLC plants are located in the Baltimore 

Nonattainment Area. 

Ravens Power Holdings, 

Brandon Shores 1 & 2, Anne Arundel County 

H. A. Wagner 2 & 3, Anne Arundel County 

C. P. Crane 1 & 2, Baltimore County 

Mirant System

Chalk Point 1 & 2, Prince George’s County 

Dickerson 1, 2, & 3, Montgomery County 

Morgantown 1 & 2, Charles County 

Allegheny Energy Washington County

R. Paul Smith, 3 & 4 

Overview of Expected Emission Reductions 

Over ninety-five percent of the air pollution emitted from Maryland’s power plants comes from the 

largest and oldest coal burning plants. The emission reductions from the Healthy Air Act come in 

two phases. The first phase requires reductions in the 2009/ 2010 timeframe, and compared to a 

2002 emissions baseline, reduce NOx emissions by almost 70%, SO2 emissions by 80% and 

mercury emissions by 80%. 

The second phase of emission control occurs in the 2012/2013 timeframe. At full implementation 

the HAA will reduce NOx emissions by approximately 75 percent from 2002 levels, SO2 emissions 

will be reduced by approximately 85 percent from 2002 levels, and mercury emissions will be 

reduced by 90 percent. 

Table 8-2: Annual Maryland Healthy Air Act NOx Emissions Reductions (TPY): 

Unit 

2002 

Emissions 

Uncontrolled 

2009 

Emissions 

2009 

HAA 

Caps 

2009 HAA 

Emission 

Reductions 

2009 HAA 

Emission 

Reduction %

2012 

HAA 

Caps 

2009 

Uncontrolled 

Emissions - 

2012 HAA Cap 

2012 HAA 

Emission 

Reduction % 

Brandon 

Shores 1 6329 7558 2927 4631 61.27 2414 5144 68.06 

Brandon 

Shores 2 6034 7206 3055 4151 57.60 2519 4687 65.04 

Wagner 2 2232 2666 673 1993 74.76 555 2111 79.18 

Wagner 3 1718 2052 1352 700 34.11 1115 937 45.66 

Crane 1 6245 7458 832 6626 88.84 686 6772 90.80 

Crane 2 4285 5117 894 4223 82.53 737 4380 85.60 

TOTALS 26843 32057 9733 22324 69.64 8026 24031 74.96 

Baltimore Serious Area 8-Hour Ozone SIP Page 64
Table 8-3: Ozone Season Maryland Healthy Air Act NOx Emissions Reductions* 

Unit 

(a) 2002 

Emissions 

(Ozone 

Season 

Day) 

(b) 2002 

Emissions 

(Ozone 

Season = 

153 Days) 

(c) 

Uncontrolled 

2009 

Emissions 

(Ozone 

Season Day) 

(d) 

Uncontrolled 

2009 

Emissions 

(Ozone 

Season = 153 

Days) 

(e) 2009 

HAA 

Caps 

(Ozone 

Season = 

153 Days)

(f) 2009 

HAA 

Emission 

Reductions 

(Ozone 

Season) 

(g) 2009 

HAA 

Reductions 

(Ozone 

Season Day)

(h) 2012 

HAA Caps 

(Ozone 

Season = 

153 Days) 

(i) 2009 

Uncontrolled 

Emissions - 

2012 HAA 

Cap (Ozone 

Season) 

(j) 2009 

Uncontrolled 

Emissions - 

2012 HAA 

Cap (Tons 

Per Ozone 

Season day) 

Brandon 

Shores 1 9.68 1481.04 11.56 1768.68 1363 405.68 2.65 1124 644.68 4.21 

Brandon 

Shores 2 7.60 1162.80 9.08 1389.24 1449 -59.76 -0.39 1195 194.24 1.27 

Wagner 2 6.88 1052.64 8.21 1256.13 278 978.13 6.39 229 1027.13 6.71 

Wagner 3 3.28 501.84 3.91 598.23 583 15.23 0.10 481 117.23 0.77 

Crane 1 11.86 1814.58 14.16 2166.48 345 1821.48 11.91 284 1882.48 12.30 

Crane 2 10.56 1615.68 12.61 1929.33 385 1544.33 10.09 317 1612.33 10.54 

TOTALS 49.86 7628.58 59.53 9108.09 4403 4705 30.75 3630 5478 36 

*All emissions are measured in short tons.

8.2.2 Portable Fuel Containers Rule: Phase I 

 

This measure introduces performance standards for portable fuel containers and spouts. The 

standards are intended to reduce emissions from storage, transport and refueling activities. The rule 

also included administrative and labeling requirements. Compliant containers must have the 

following: only one opening for both pouring and filling, an automatic shut-off to prevent overfill, 

an automatic sealing mechanism when not dispensing fuel, specified fuel flow rates, and permeation 

rates and warranties. 

Source Type Affected 

 

This measures affects any person or entity selling, supplying or manufacturing portable fuel 

containers, except containers with a capacity of less than or equal to one quart, rapid refueling 

devices with capacities greater than or equal to four gallons, safety cans and portable marine fuel 

tanks operating with outboard motors, and products resulting in cumulative VOC emissions below 

those of a representative container or spout. 

 

Control Strategy 

 

Maryland adopted phase I of the Ozone Transport Commission (OTC) Model Rule for Portable 

Fuel Containers in January 2002. The rule applies to all counties in the nonattainment area. 

Reductions from this rule increase annually beginning with implementation in the State of Maryland 

on January 1, 2004. 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 65
Projected Reductions 

VOC Emission Reductions for 2008 (TPD): 6.71 

VOC Emission Reductions for 2011 (TPD): 8.31 

VOC Emission Reductions for 2012 (TPD): 8.35 

Emission Benefit Calculations 

 

Projected reductions are based on an emission reduction factor of 75% after full implementation 

after 10 years. Implementation began in 2004. 

 

References 

 

E.H. Pechan, “Control Measure Development Support Analysis for the Ozone Transport 

Commission Model Rules”, March 31, 2001. 

8.2.3 Architectural and Industrial Maintenance Coatings Rule 

 

This rule requires manufacturers to reformulate various types of coatings to meet VOC content 

limits. Affected products include architectural coatings, traffic markings, high-performance 

maintenance coatings and other special-purpose coatings. It uses more stringent VOC content limits 

than the existing federal consumer products rule. 

 

Source Type Affected 

 

The measure affects all manufacturers of affected coatings. 

 

Control Strategy 

 

Maryland adopted this rule on March 29, 2004. The rule applies to all counties in the nonattainment 

area. Compliance with this rule was required as of January 1, 2004. 

 

The VOC content limits in this rule are based on a Suggested Control Measure (SCM) adopted by 

the California Air Resources Board (CARB) and a National Association of Clean Air Agencies 

(NACAA) model rule or OTC coatings. Manufacturers are expected to comply with this rule using 

primarily EPA Test Method 24. 

 

Projected Reductions 

VOC Emission Reductions for 2008 (TPD): 6.03 

Baltimore Serious Area 8-Hour Ozone SIP Page 66
VOC Emission Reductions for 2011 (TPD): 6.19 

VOC Emission Reductions for 2012 (TPD): 6.19 

Emission Benefit Calculations 

 

Projected reductions are based on an emission reduction factor of 31 percent, based on Pechan 

(2001). 

References 

 

E.H. Pechan, “Control Measure Development Support Analysis for the Ozone Transport 

Commission Model Rules”, March 31, 2001. 

8.2.4 Consumer Products Rule: Phase 1 

Phase I of the Consumer Products Rule required reformulation of approximately 80 types of 

consumer products to reduce their VOC content. It uses more stringent VOC content limits than the 

existing federal consumer products rule. The rule also contains requirements for labeling and 

reporting. 

 

Source Type Affected 

 

Manufacturers of various specialty chemicals named in the rule, such as aerosol adhesives, floor 

wax strippers, dry cleaning fluids and general purpose cleaners 

 

Control Strategy 

 

Phase I of the Ozone Transport Commission Model Rule for Reformulated Consumer Products 

became effective in the State of Maryland on August 18, 2003. 

 

Manufacturers are expected to demonstrate compliance with the rule primarily through a California 

Air Resources Board test method. If complying with the VOC contents becomes difficult, flexibility 

options are provided. 

Projected Reductions 

VOC Emission Reductions for 2008 (TPD): 3.70 

VOC Emission Reductions for 2011 (TPD): 3.77 

VOC Emission Reductions for 2012 (TPD): 3.79 

Baltimore Serious Area 8-Hour Ozone SIP Page 67
Emission Benefit Calculations 

 

Projected reductions are based on an emission reduction factor of 14.2 percent, based on Pechan 

(2001). 

References 

 

E.H. Pechan, “Control Measure Development Support Analysis for the Ozone Transport 

Commission Model Rules”, March 31, 2001. 

8.2.5 Industrial Adhesives and Sealants Rule 

 

This rule establishes VOC content limitations for industrial and commercial application of solventbased adhesives and sealants. Controls will cover adhesives, sealants, adhesive primers, sealer 

primers, adhesive application to substrates, and aerosol adhesives. VOC content limits are similar 

to those contained in the CARB Reasonably Available Control Technology (RACT) or Best 

Available Control Technology (BACT) document for adhesives and sealants (Dec. 1998). 

 

Source Type Affected 

 

Manufacturers and distributors of industrial adhesives and sealants 

 

Control Strategy 

 

The State of Maryland will adopt the Ozone Transport Commission (OTC) Model Rule for 

Industrial Adhesives and Sealants in time such that the effective date of emissions reductions occurs 

no later than May 1, 2009. 

 

Projected Reductions 

VOC Emission Reductions for 2008 (TPD): 0.00 

VOC Emission Reductions for 2011 (TPD): 2.63 

VOC Emission Reductions for 2012 (TPD): 2.64 

 

Emission Benefit Calculations 

 

Emission benefits are based on a 64 percent reduction in emissions of VOC from the baseline. 

Further details are available in OTC (2006). 

Baltimore Serious Area 8-Hour Ozone SIP Page 68
References 

 

OTC 2006. Identification and Evaluation of Candidate Control Measures: Draft Technical 

Support Document. Prepared by MACTEC Federal Programs, Inc., Herndon, Virginia for the 

Ozone Transport Commission. August 4, 2006. 

8.2.6 Portable Fuel Containers Rule: Phase II 

 

This measure expands existing performance standards for portable gasoline containers and spouts to 

kerosene containers. The standards are intended to reduce emissions from storage, transport and 

refueling activities. The rule also includes administrative and labeling requirements. Compliant 

containers must have the following: only one opening for both pouring and filling; an automatic 

shut-off to prevent overfill; an automatic sealing mechanism when not dispensing fuel; and 

specified fuel flow rates, permeation rates and warranties. 

 

Source Type Affected 

 

This measure affects any person or entity selling, supplying or manufacturing portable fuel 

containers, except containers with a capacity of less than or equal to one quart, rapid refueling 

devices with capacities greater than or equal to four gallons, safety cans and portable marine fuel 

tanks operating with outboard motors, and products resulting in cumulative VOC emissions below 

those of a representative container or spout. 

 

Control Strategy 

 

The State of Maryland has adopted the Ozone Transport Commission (OTC) Model Rule for 

Portable Fuel Containers Phase II in time such that the effective date of emissions reductions occurs 

no later than May 1, 2008. 

 

Projected Reductions 

VOC Emission Reductions for 2008 (TPD): 0.00 

VOC Emission Reductions for 2011 (TPD): 0.60 

VOC Emission Reductions for 2012 (TPD): 0.60 

Emission Benefit Calculations 

 

Projected reductions are based on an emission reduction factor of 58% after full implementation 

after 10 years. Implementation began in 2004. In 2008, the emission reduction factor is 0.00%. In 

2009, the emission reduction factor is 5.8%. Further details are available in OTC Technical Support 

Document (2006). 

Baltimore Serious Area 8-Hour Ozone SIP Page 69
References 

 

[OTC 2006. Identification and Evaluation of Candidate Control Measures: Draft Technical 

Support Document. Prepared by MACTEC Federal Programs, Inc., Herndon, Virginia for the 

Ozone Transport Commission. August 4, 2006] 

8.2.7 Consumer Products Rule: Phase II 

Phase II of the Consumer Products Rule involves adopting the CARB 7/20/05 Amendments which 

set new or revise existing limits on 13 consumer product categories. It uses more stringent VOC 

content limits than the existing federal consumer products rule. The rule also contains requirements 

for labeling and reporting. 

 

Source Type Affected 

 

Manufacturers of various specialty chemicals named in the rule, such as aerosol adhesives, floor 

wax strippers, dry cleaning fluids and general purpose cleaners 

 

Control Strategy 

 

The State of Maryland will adopt the Ozone Transport Commission (OTC) Model Rule for 

Consumer Products Phase II in time such that the effective date of emissions reductions occurs no 

later than May 1, 2008. 

 

Projected Reductions 

VOC Emission Reductions for 2008 (TPD): 0.00 

VOC Emission Reductions for 2011 (TPD): 0.46 

VOC Emission Reductions for 2012 (TPD): 0.46 

Emission Benefit Calculations 

 

Emission reductions are based on an additional 2 percent reduction in emissions of VOC from the 

baseline. Further details are available in OTC Technical Support Document (2006). 

 

References 

 

[OTC 2006. Identification and Evaluation of Candidate Control Measures: Draft Technical 

Support Document. Prepared by MACTEC Federal Programs, Inc., Herndon, Virginia for the 

Ozone Transport Commission. August 4, 2006] 

Baltimore Serious Area 8-Hour Ozone SIP Page 70
Rule Phase In 

The following rules have a phase in period for the Baltimore Nonattainment Area and give the 

region phased-in emissions benefits: 

Area Sources: 

 Additional phase in of reductions from Federal Locomotives Rule 

 Federal Rule related to On-Board Refueling/Vapor Recovery for LD Trucks (2004) 

Nonroad Sources: 

 Federal 2004 Nonroad Heavy Duty Diesel Rule (negligible benefits by 2009) 

8.3 VOLUNTARY AND INNOVATIVE MEASURES 

EPA’s voluntary measures policy, “Guidance on Incorporating Voluntary Mobile Source Emission 

Reduction Programs in State Implementation Plans,” establishes criteria under which emission 

reductions from voluntary programs are creditable in a SIP. This policy permits states to develop 

and implement innovative programs that partner with local jurisdictions, businesses and private 

citizens to implement emission-reducing behaviors at the local level. 

Inclusion of the programs below in the “Control Measures” portion of this attainment plan is not 

intended to create an enforceable commitment by MDE or the State of Maryland to implement the 

programs or to achieve any specific emission reductions projected as a result of implementation of 

the programs, and neither MDE nor the State makes any such commitment. In addition, MDE does 

not rely on any emission reductions projected as a result of implementation of these programs to 

demonstrate attainment. While the emission reductions from these programs could be substantial 

and could lead to significant regional air quality benefits, actual air quality benefits are uncertain. 

Consequently, projected emission reductions from these programs are not included in the emission 

inventory, the attainment modeling, the reasonable further progress calculation or any other area of 

the SIP where specific projected emission reductions are identified. 

8.3.1 Regional Forest Canopy Program: Conservation, Restoration, and 

Expansion 

 

Expanded tree canopy cover is an innovative voluntary measure proposed to improve the air quality 

in the Baltimore region. Trees reduce ground-level ozone concentrations by the following means: 

1) Reducing air temperatures and reducing energy used for cooling, and 

2) Directly removing ozone and NOx from the air. 

Modeling has clearly shown that trees reduce ozone levels. In addition, trees in an urban setting 

have far-reaching water quality habits (e.g. decreasing storm water runoff) and societal benefits. To 

Baltimore Serious Area 8-Hour Ozone SIP Page 71
achieve a reduction in ground-level ozone under a tree canopy program, it is necessary to preserve 

the current canopy and plant and maintain a significant number of new trees. 

The current Baltimore region tree canopy is composed of mixed native hardwoods and urban 

plantings. On average these species require 30 years to mature, so the short-term benefits of a tree 

program are not substantial yet the long-term benefits are still significant. To achieve area-wide 

canopy expansion requires long-term commitment by the state and local agencies, volunteer 

organizations, and private landowners. 

Achieving maximum benefits from this type of program requires the following types of 

commitments: 

1) Initiate and/or enhance efforts to support, monitor, evaluate, and report preservation of existing 

urban tree canopy and canopy expansion efforts. 

2) Implement urban forestry programs to affect air temperature, surface temperature, and wind 

speed and reduce VOC emissions. Programs include sustained tree planting, reduced mowing, and 

lawn maintenance. Also included are tree planting initiatives for streets, parking lots, and 

government-owned facilities. 

3) Provide assistance and outreach to landowners and businesses to encourage tree conservation, 

planting and maintenance. 

4) Initiate development of a comprehensive plan that establishes a detailed regional baseline and 

outline strategies to preserve, enhance, increase, protect, measure, and track overall forest canopy 

change in the region over the next 20 years. 

5) Monitor these activities and report annually. 

Current Programs 

While Maryland has over 40 state programs that support, encourage or require the planting of trees, 

five of these tools are of special importance for implementation at the local level: 

 Forest Conservation Act 

 Critical Areas Act 

 Mitigation Requirements 

 Comprehensive Plans Requirements 

 Urban and Community Forestry Programs 

Special attention will be paid to how these programs can be coordinated with new local ordinances 

and initiatives to enhance their use in tree protection, canopy preservation and expansion to achieve 

regional air quality (SIP) goals. 

Baltimore Serious Area 8-Hour Ozone SIP Page 72
Control Strategy 

Coordination 

This type of measure requires collaboration among the various state and local agencies that support, 

encourage, and require tree planting. Currently, numerous agencies bear responsibility for 

implementing and tracking tree planting related activities, but there is no centralized repository for 

this information. The state can be encouraged to commit to create a new program to coordinate 

tree-planting programs. This program would be housed within the Department of Natural 

Resources’ Maryland Forest Service and would be charged with management of a tree planting 

database and promoting outreach efforts to landowners and stakeholder groups. This database 

would be used to compile baseline data, including maps and descriptive information about each 

nonattainment county in the planning area; information about tree plantings, including new and 

replacement trees; and canopy change. 

Canopy Preservation 

The state coordinating office will work with local governments to fully implement key programs. 

Particular attention will be given to those who set conservation, tree planting and canopy goals and 

reforestation standards for local authorities to track during the development process. Local 

authorities will be encouraged to do the following: 

1) Track efforts aimed at preserving existing canopy, 

2) Provide the resource agency with data regarding preservation efforts including new 

ordinances and development tools, and 

3) Work with federal, state and private landowners to identify development mitigation areas. 

The effectiveness of canopy preservation efforts could then be periodically evaluated. 

Public Outreach 

The region would need to commit to undertake a public outreach program designed to promote tree 

planting. This need could be addressed building upon the Chesapeake Bay Agreement Forestry 

Directive and local land use guidelines. Past initiatives under Maryland programs have included 

financial incentives to private landowners for planting trees. The Baltimore Metropolitan Council, 

state government agencies, and local governments could work with volunteer tree planting 

organizations, landowners, and stakeholder groups to support tree planting and conduct educational 

outreach regarding documenting and reporting voluntary planting and maintenance programs. 

Canopy Goals 

Each jurisdiction in the nonattainment area could be encouraged to adopt a tree canopy goal. Local 

and state governments could evaluate reforestation of public lands to meet canopy goals. 

Governments could collaborate with private citizens to address canopy goals. 

Baltimore Serious Area 8-Hour Ozone SIP Page 73
Strategic Tree Planting 

Biogenic volatile organic compounds (BVOCs), an ozone precursor, are emitted by some tree 

species as a natural process. Expanding the canopy primarily with trees whose BVOC emissions 

are lower will have a significant impact on overall emissions; planting lower BVOC trees is a key 

approach to reducing BVOCs. A right tree – right place strategy will need to be encouraged to 

garner the maximum benefits from this type of program. 

8.3.2 Clean Air Teleworking Initiative 

The State of Maryland, on occasion experiences unhealthful levels of the air pollutants, groundlevel ozone and fine particles. When air quality elevates to unhealthful levels, it poses significant 

health and economic impacts on Maryland residents. Since 1990, when the modern-day Clean Air 

Act was passed, to address air pollution concerns and requirements Maryland has implemented over 

100 pollution control programs affecting industries, small businesses, mobile sources, and the 

general public. These programs have prevented nearly 800 tons of ozone-forming pollutants from 

entering the air each day. In order to inform the public about daily air pollution levels, the 

Maryland Department of the Environment has been accurately forecasting and reporting air quality 

information since 1993. 

Traffic congestion is a major problem in Maryland’s metropolitan areas where individuals waste 

hundreds of hours every year stuck in traffic due to congested roadways. Numerous studies have 

demonstrated that telework (or “telecommuting”) programs are advantageous in addressing major 

environmental, transportation, productivity, quality of life, and employment issues. 

Reducing the number of road miles traveled by commuters decreases air polluting vehicle 

emissions, gasoline consumption, traffic congestion, and highway maintenance costs for Maryland 

residents. Telework provides economic and organizational benefits to employers, resulting in 

increased employee productivity, enhanced employee morale, improved employee recruitment and 

retention, reduced office space and parking needs, reduced stress, increased job satisfaction, 

decreased absenteeism costs, an expanded labor pool, and increased flexibility in meeting the needs 

of state residents. Maryland, as a major employer, has recognized its leadership role in developing 

substantive programs, such as teleworking, to reduce commuter road miles traveled by state 

employees and enhance productivity. 

Objective 

The objectives of the Clean Air Telework initiative are as follows: to 1) increase the number of 

employees who telework in the Baltimore/Washington metropolitan area and, 2) increase the 

frequency of employees who telework by linking teleworking with air quality; specifically, 

encouraging employees to telework on days when air quality is at its worst. 

The decision to encourage teleworking on bad air days will be guided by the Air Quality Index 

(AQI), a nationwide, color-coded scale used by the U.S. Environmental Protection Agency to 

communicate air quality to the public. “Code Orange” is considered unhealthy for sensitive groups

(children, the elderly, and those with heart or lung conditions) and “Code Red” is considered 

Baltimore Serious Area 8-Hour Ozone SIP Page 74
unhealthy for everyone. “Code Purple,” which occurs very infrequently in the region, is considered 

very unhealthy for everyone. Clean Air Partners, a nonprofit organization that encourages 

voluntary action to improve air quality, provides a three-day air quality forecast to local employers 

through its Air Quality Action Day (AQAD) program. A copy of Clean Air Partners’ Air Quality 

Action Guide, which incorporated the AQI, is shown in Figure 8-1. Teleworking is encouraged at 

Code Orange and above. 

 

 

Figure 8-1: Air Quality Action Guide 

Baltimore Serious Area 8-Hour Ozone SIP Page 75
Approach 

Encouraging employees to telework on poor air quality days may result in numerous employees and 

managers working at home for several consecutive days. This will require advanced preparation by 

employees, managers, and office coworkers to ensure transparency and a consistent level of 

productivity. While this may initially seem challenging from a management perspective, the added 

benefit is that employees and managers will become adept at teleworking concurrently, thereby 

increasing the organization’s business continuity capabilities in the event of an actual emergency. 

Implementation 

The following steps are recommended to help businesses successfully launch their “Clean Air 

Teleworking” initiative: 

Get Input from Managers – Businesses should get input from several managers to identify 

potential barriers and solutions to the “Clean Air Teleworking” initiative. This could be 

accomplished by conducting one-on-one interviews with 4-5 managers or a small discussion group. 

The input from the managers could then be used to shape the development and implementation of 

the program, starting with a small pilot involving a couple of managers supportive of teleworking 

and the “Clean Air Teleworking” initiative. 

Become an AQAD Participant – Businesses should become Air Quality Action Days participants 

so they can receive the Clean Air Partners’ three-day air quality forecast, which can then be 

distributed by email to employees when a poor air quality day (Code Orange, Code Red, or Code 

Purple) is forecasted. 

Conduct Pilot – Businesses should select managers and employees who will be participating in the 

“Clean Air Teleworking” pilot and launch the program over the summer of 2007. Conduct an 

orientation/training session for participants prior to implementation and follow up with brief phone 

interviews after a multi-day episode to determine if there were any problems. Prepare a summary 

report at the end of the pilot and share with management and employees. 

Implement Tracking System – Ask participants to track their participation using a Web-based 

system that tracks reductions in vehicle emissions, particularly NOx, VOC, CO, and CO2, resulting 

from teleworking. An example is of such a Web-based system is TeleTrips (https://www.secureteletrips.com/). The information collected can be reported at the individual, department/team, and 

organizational level and provides continuous feedback on how the program and participants are 

improving air quality. Furthermore, businesses should consider recognizing individuals or 

teams/departments with the highest level of participation and emissions reductions. 

Communicate – Businesses should send out several email communications to all their employees; 

including, prior to the launch of the “Clean Air Teleworking” pilot, during implementation, and at 

the conclusion of the pilot. The emails should explain pilot program objectives and keep employees 

informed. Furthermore, employees not participating in the pilot should also receive the air quality 

forecast for Code Orange, Code Red, and Code Purple days and be encouraged to take other 

voluntary measures at work and at home (e.g., carpooling, eating in the cafeteria rather than going 

out for lunch, refueling after dusk, and postponing mowing lawns.) 

Baltimore Serious Area 8-Hour Ozone SIP Page 76
Expand Program – Businesses should share the results of the pilot with all staff and encourage 

additional managers and employees to participate in the program in future years. Repeat 

orientation/training for new participants prior to implementation, conduct phone or on-line survey 

with participants during implementation, track participation and results for all participants, and 

recognize or reward individuals, teams, and departments with the highest level of participation and 

emissions reductions. 

An initial pilot program will be initiated throughout the Maryland Department of the Environment 

(MDE). It will encourage telecommuting opportunities for qualified personnel when air quality is 

forecasted to be in the Code Orange (Unhealthy for Sensitive Groups) range or above. The MDE 

pilot program will launch in May 2007. 

Additional strategies will be employed to encourage a wider participation in the Clean Air 

Teleworking Initiative. Examples include these: 

 Promote participation among all Maryland State agencies; 

 Collaborate with the Baltimore Metropolitan Council and the Metropolitan Washington 

Council of Governments to promote the initiative throughout the local jurisdictions; Clean 

Air Partners will serve as the work group to implement the program; 

 Develop a strategic plan for local governments and federal agencies; 

 Encourage participation within the private sector; 

 Develop a merit-based recognition/award system for participation; and 

 Promote program throughout the Ozone Transport Commission. 

A timeline of the implementation steps is shown in Table 8-4. 

Table 8-4: Clean Air Teleworking Time Line 

Task/Step Apr-07 May-07 Jun-07 Jul-07 Aug-07 Sep-07 Oct-07 Nov-07 Dec-07

1.0 Telework Toolkit 

1.1 Research materials x 

1.2 Compile toolkit X 

1.3 Integrate with Clean Air Partners web site x 

 

2.0 Clean Air Teleworking Pilot 

2.1 Recruit organization(s) x x 

2.2 Develop/implement communications plan x x 

2.3 Conduct interviews/focus groups with managers x x 

2.4 Identify participants (e.g., specific units/departments) x x 

2.5 Conduct orientation x 

2.6 Launch and conduct pilot x x X x 

2.6 Conduct "spot" phone interviews/email surveys x x X x 

2.7 Implement tracking system x x x X x 

2.8 Track and report results x x x X x x x 

2.9 Expand program x x 

Baltimore Serious Area 8-Hour Ozone SIP Page 77
The Clean Air Teleworking Initiative will be developed in close coordination with other entities 

who have a role in telework implementation: Commuter Connections, Maryland Telework 

Partnership with Employers, Telework!Va, and the newly created Office of Telework Promotion 

and Broadband Assistance in VA. 

Supporting Material

Clean Air Partners will compile and customize a telework tool kit that would be posted on the 

organization’s Web site. The tool kit would provide on-line resources to help employers start or 

expand a telework program, including the use of “episodic” teleworking on poor air quality days. 

University of Maryland Study of Air Quality Benefits of Teleworking 

To simulate the effects of a very aggressive telework initiative, the University of Maryland modeled 

the air quality change that would result if 40% of all light duty vehicles were taken off the road in 

the nonattainment areas of Baltimore, Philadelphia, and Washington, D.C. on 38 high ozone days in 

the summer of 2002. Changes in emissions were implemented as a flat 40% reduction in vehicle 

miles traveled in each county of the three nonattainment areas. The effects of implementing such a 

program were modeled using version 4.4 of the CMAQ model. The model results showed that 

across the three nonattainment areas, an aggressive telework program has the potential for 

considerable benefit to air quality, with fairly uniform benefits across all three areas. The highest 

monitors in the Philadelphia and Washington, D.C. areas would see the largest benefits from this 

program, suggesting it is reaching the most troublesome monitors on the worst ozone days. 

Benefits in all three nonattainment areas averaged more than 2 ppbv ozone. 

8.3.3 High Electricity Demand Day (HEDD) Initiative 

Emissions from Electric Generating Units (EGUs) are higher on high electric demand days 

(HEDD), resulting in poorer air quality. High electrical demand day operation of EGUs generally 

has not been addressed under existing air quality control requirements, and the HEDD units are 

called into service on the very hot days of summer and on very cold days of winter when air 

pollution levels typically reach their peaks. HEDD units include gasoline and diesel combustion 

turbines as well as residual oil burning units. 

The Ozone Transport Commission (OTC) has been meeting with state environmental and utility 

regulators, EPA staff, EGU owners and operators and the independent regional systems operators. 

The purpose of these meetings has been to assess emissions associated with HEDD during the 

ozone season and to address excess NOx emissions on HEDDs. The OTC has found that NOx 

emissions are much higher on a high electrical demand day than on a typical summer day. The 

potential exists to reduce HEDD emissions by approximately 25 percent in the short term through 

the application of known control technologies. 

On March 2, 2007, the OTC states and the District of Columbia agreed to a Memorandum of 

Understanding (MOU) committing to reductions from the HEDD source sector. The MOU includes 

specific targets for a group of six states to achieve reductions in NOx emissions associated with 

HEDD units on high electrical demand days during the ozone season. These states agreed to achieve 

these reductions beginning with the 2009 ozone season or as soon as feasible thereafter, but no later 

Baltimore Serious Area 8-Hour Ozone SIP Page 78
than 2012. The OTC states not included in the MOU, including Virginia and the District of 

Columbia, agreed to continue to review the HEDD program and seek reductions where possible, but 

they do not have a formal emissions reduction target in the MOU. The OTC MOU is included in 

Appendix C. 

8.3.4 Emission Reductions from Transportation Measures 

Substantial funding commitments have come from State and local agencies and private employers 

for promotion of strategies to reduce mobile emissions. Examples of these measures include idling 

reduction, ridesharing, teleworking, transit use, vehicle replacement and retrofit measures, and 

bicycle and pedestrian programs. These funding commitments produce reductions in emissions, 

some of which are being reflected in transportation plans. 

Although these programs are working to reduce emissions from mobile sources and play an 

important role in the transportation sector’s contribution to cleaner air, neither MDE, nor the State 

intends their inclusion in this SIP to constitute enforceable commitments to implement these 

programs or to achieve any emission reductions projected as a result of implementing these 

programs, and neither MDE, nor the State makes any such commitment. These directionally correct 

programs will continue to be used outside of the SIP for transportation planning purposes as needed. 

The following are descriptions of selected emission reduction strategies in the Baltimore region. 

Clean and Efficient Strategies 

With the support of both state and federal funds, MDE has worked with several local governments 

to introduce new technologies designed to reduce emissions of their in-use fleets. The MDE 

worked successfully with Baltimore City to retrofit 108 trash haulers, 23 dump trucks and 49 firetrucks with diesel oxidation catalysts (DOCs) and closed crankcase ventilation filtration systems 

(CCVFSs). These systems help reduce PM emissions from both the exhaust systems and from the 

engine. MDE is also supporting the installation of two “Quick Charge” recharging units in 

Baltimore City. These chargers allow the city to recharge its fleet of electric vehicles in under an 

hour, compared with the previous time of 6 hours. This will encourage the City to purchase more 

electric vehicles for its downtown fleet. MDE is also working with Johns Hopkins University to 

retrofit its fleet of 10 diesel vehicles with DOCs and CCVFSs as well as install a “Quick Charger” 

unit at its main campus. MDE has worked with Howard County to successfully retrofit 25 of their 

transit buses with DOCs, CCVFSs, and International Clean diesel kits. This project is reducing both 

particulate matter and NOx emissions. MDE has also worked with Anne Arundel County Public 

Schools to retrofit their fleet of 51 diesel-powered school buses with DOCs and CCVFSs. Finally, 

MDE is in the process of retrofitting 10 fire trucks for the City of Annapolis. These vehicles will be 

retrofitted with DOCs and CCVFSs. 

Traffic Flow Improvements (CHART) 

The Coordinated Highways Action Response Team (CHART) program, operated by MDOT and 

Maryland State Police, focuses its operations on non-recurring congestion such as backups caused 

by accidents. The Statewide Operations Center, and the three satellite Operations Centers in the 

region, survey the state’s roadways to quickly identify incidents through the use of Intelligent 

Transportation System (ITS) technology. CHART also includes traffic patrols, which have been 

operating during peak periods on many of the state highways in the region since the early 1990s. 

Baltimore Serious Area 8-Hour Ozone SIP Page 79
Based on 2005 data, it has been estimated that CHART operations saved 37.3 million vehicle hours 

of delay statewide including 21.3 million in the Baltimore region; saved 6.3 million gallons of fuel; 

and reduced overall mobile source emissions. 

Truck Stop Electrification (TSE) 

Truck Stop Electrification allows truckers to shut down their engine and obtain electric power and 

“creature comforts” while resting. TSEs reduce diesel emissions and reduce noise and wear and tear 

on the truck engine. IdleAire truck stops provide electricity (110V AC), cab heating/cooling, 

television and movies, telephone and Internet access. IdleAire has over 100 locations nationally, 

including three in Maryland. The Maryland sites are located in Baltimore and Jessup, both in the 

Baltimore region. An additional TSE has been put in place in Cecil County at I-95 and MD 279. 

Electronic Toll Collection 

The Maryland Transportation Authority (MDTA) commenced operation of its electronic toll 

collection system, M-TAG, at the authority’s three harbor crossing facilities in 1999. By fall 2001, 

all toll facilities in the region were equipped with electronic toll collection equipment. As of 

January 2004, 45 percent of vehicles using MDTA facilities used electronic toll tags. MDTA is a 

member of the E-Z Pass InterAgency Group, a coalition of Northeast Toll Authorities. MDTA 

established reciprocity with the E-Z Pass system in 2001, enabling travelers in Maryland, as well as 

at most toll facilities in New York, New Jersey, Delaware, Pennsylvania, Massachusetts, Virginia, 

and West Virginia to pay tolls using one electronic device. 

Traffic Signal System Retiming 

SHA has instituted a program to review and retime its 1,200 traffic signals in the Baltimore region. 

The timing of each traffic signal system is reviewed and updated every three years. In addition, 

systems in high profile corridors or corridors subject to significant traffic pattern change are 

evaluated on a more frequent schedule. This program results in smoother traffic flow as well as 

reduced emissions resulting from idling vehicles. Synchro software is used to develop new timing 

plans and to calculate benefits from the new timing plans. This program has resulted in the 

following average annual benefits for the Baltimore region: 11.8 percent reduction in network 

delay; 8.5 percent reduction in arterial delay; 8.7 percent reduction in arterial stops; and 1.9 percent 

reduction in fuel consumption. 

Ride Share 

The Baltimore region’s original rideshare program began in 1974 as a joint effort of Baltimore City, 

the Regional Planning Council (now the Baltimore Metropolitan Council), and MDOT. Efforts to 

encourage ridesharing were expanded to cover the entire state in 1978 when the Maryland 

Ridesharing Office of the Maryland Transit Administration (MTA) was established. Since it was 

formed, the MTA has enhanced and expanded its activities to include both commuters and their 

employers. A continuing program administered by the MTA provides funding support to local 

rideshare coordinators in order to strengthen ride matching and rideshare-support services at the 

jurisdictional level. The BMC provides ridesharing coordination services for Baltimore and Carroll 

Counties. Local rideshare coordinators have provided ridesharing information that has helped in the 

development of more effective regional emission reduction strategies. They have also assisted 

employers and employees in identifying opportunities for other Emission Reduction Strategies 

(ERSs) such as transit, flexible work hours, and telecommuting. 

Baltimore Serious Area 8-Hour Ozone SIP Page 80
Maryland Commuter Tax Credit 

In January 2000, a tax credit went into effect statewide that allows employers to claim a 50% state 

tax credit, up to $52.50 per month, for providing transit benefits in the form of a subsidy to an 

employee. An employer may provide this benefit to an employee without tax consequences under 

the federal tax law. It is expected that the state tax credit will be even more attractive to employers 

as a benefit to offer employees than is the federal law; the state benefit is a direct tax credit as 

opposed to an allowable business expense, the case of the federal program. This feature of the 

Maryland law also has the potential to encourage increased transit use by low and moderate-income 

employees. Under provisions of both the 1999 and 2000 Maryland laws, private non-profit 

organizations will also be able to participate in the program. Employers will be able to claim tax 

credits for providing transit passes and vouchers, guaranteed ride home, and parking cash-out 

programs. Similar to the IRS benefits, the Maryland Commuter Tax Benefit program does not 

provide financial assistance to carpoolers. Information is also provided online and employers are 

able to register over the Internet to participate in the program. 

Clean Commute Month 

The Baltimore Regional Transportation Board (BRTB) has teamed with state transportation and air 

quality agencies as well as private organizations to promote Clean Commute Week. The program 

was expanded in 2003 and is now known as Clean Commute Month (CCM). During CCM, 

residents of the Baltimore region are asked to try an alternative to driving alone for at least one day 

during May. Clean Commute Month 2006 promotion began in late April, with a number of outreach 

events throughout the region. Events continued through May, and included a Bike to Work Day. 

Participation in Bike to Work Day has increased substantially in recent years, and many local 

businesses and organizations donate prizes for registered participants. Bike to Work Day, a true 

region-wide initiative, features rallies in Annapolis; Baltimore City; and Baltimore, Carroll, Harford 

and Howard Counties. With a grant from MDE, CCM 2006 also included Clean Car Clinics, where 

certified technicians provided free car inspections to the public. 

Telework Partnership with Employers 

BMC and MWCOG participate in a bi-regional program to assist large and small employers to 

establish home-based telecommuting programs for their employees. This program, known as the 

“Telework Partnership with Employers,” or “TPE,” is funded by MDOT. In addition to the traffic 

and emission reduction benefits of the TPE program, the TPE program assists in perfecting 

marketing, outreach procedures, and administrative methods that may be used in other alternate 

commute programs. Since its kickoff in October 1999, over 25 large and small private sector 

employers as well as two nonprofit organizations have been recruited to participate in the biregional TPE program. In the Baltimore region, eight employers have taken advantage of the TPE 

and several others are currently considering the program. Employers are recruited through outreach 

events. Employers that have signed up to participate in year-long pilot programs choose from a list 

of qualified regional and national telecommuting consultants whose services are paid for by MDOT. 

Transit Oriented Development 

The transit oriented development (TOD) in Owings Mills in Baltimore County is an example of 

long-range planning which has resulted in the location of high-density commercial and residential 

development within close proximity of the Baltimore subway system’s Owings Mills station and the 

transit bus stop. Similar developments are planned or underway in other parts of the Baltimore 

region. 

Baltimore Serious Area 8-Hour Ozone SIP Page 81
Bicycle/Pedestrian Enhancements

Bicycle commuting can provide an alternate travel mode to shorter car trips which pollute more per 

mile than longer trips. Both bicycle and pedestrian modes of travel to work, when used alone or in 

combination with transit, can help to reduce traffic congestion by taking cars off the road. Bicycling 

and walking lend themselves to smart growth land uses such as transit oriented and mixed use 

developments. They also work well with travel demand management and “live near your work” 

programs. The physical activity involved in cycling and walking also provide health benefits of 

exercise which is important considering the current problem of obesity in the United States. 

Through MDOT, the Maryland State Highway Administration (SHA) has worked to engineer and 

implement new and improved bicycle and pedestrian facilities, and SHA has implemented programs 

to encourage walking. SHA has a stated goal of providing 200 miles of marked bicycle lanes 

throughout Maryland by December 31, 2006. In addition, SHA has developed the Maryland SHA 

Bicycle and Pedestrian Guidelines to provide general guidance on design. The state has a policy of 

considering sidewalks to reinforce pedestrian safety and promote pedestrian access adjacent 

to roadways under construction or reconstruction. Special efforts are made to facilitate pedestrian 

travel near schools. 

In addition, bicycle safety and bicycle travel in general are being improved through the construction 

of wider shoulders and/or curb lanes to separate motor vehicles from the cyclists. In regard 

to bicycle or pedestrian travel in controlled access roadway corridors, a separation almost always 

exists between the bike or pedestrian travel and the motor vehicles. It is only along roadways where 

the vehicle speeds or mix of the travel modes could result in serious accidents that sidewalks and 

bicycle travel not promoted. 

 

Beginning in 2005 improvements to existing sidewalks or new sidewalk construction has taken 

place along many roadways in the Baltimore region. These roads include MD 2, MD 435, MD 26, 

MD 134, MD 140, MD 7, MD 150, MD 542 and MD 648. In addition, since 2005, separate bike or 

pedestrian paths have been constructed to facilitate recreation, pedestrian shopping, or schoolrelated travel. In the Baltimore region these include the Maryland and Pennsylvania Heritage trail 

extension, Broken Land Parkway Pathway, Centennial Access Trail, Wakefield Community Trail, 

Broadneck Peninsula Trail and the South Shore Trail. 

Other recent bike/pedestrian enhancements include the following: 

 Bike to Work Day expansion in the Baltimore region 

 Quantification of benefits of bicycling as far as reductions in air pollutants (per Appendix G: 

“Recreation and Reduced Auto Use Benefits,” of the National Cooperative Highway 

Research Program (NCHRP) report Guidelines for Analysis of Investments in Bicycle 

Facilities) 

 Status of regional efforts such as BMC’s Action Plan 2001 and statewide efforts such as 

MDOT’s Twenty Year Bicycle and Pedestrian Access Master Plan. 

 Street Smart campaign- MDOT 

 Safe Routes to School- MD SHA 

 MDOT’s “Safe Bicycling in Maryland” 

 Complete Streets program 

 Free water taxi service around Baltimore Harbor 

 BMC’s “Bicycle Commuter Resource Guide for the Baltimore Region” 

Baltimore Serious Area 8-Hour Ozone SIP Page 82
MARC Station Parking Enhancements 

MARC commuter rail services have been enhanced through construction of additional parking at 

stations throughout the Baltimore region. A feasibility study is underway for structured parking 

(garage or parking deck) at Odenton Station for 2,500 spaces on the MTA owned property. In 

addition the Odenton MARC parking facilities were expanded by over 700 spaces; the facilities 

were opened in 2006. There are a total of 2,000 spaces at the location. Expansion of the Halethorpe 

MARC Station park-and-ride lot Phase I, is complete with 428 parking spaces added. The scope of 

the work includes high level platforms, new shelters, improved accessibility for persons with 

disabilities, lighting, and streetscaping. Phase II, which includes a pedestrian bridge and high level 

platforms is in the project initiation stage. In September 2005, construction began on a parking lot 

expansion at the Martin State Airport MARC station, located on the Penn Line. It was completed in 

2006. This expansion increased the number of parking spaces from 171 to 321. 

Refurbishing MARC and other rail vehicles 

In order to insure the reliability, safety and comfort of MARC equipment, the rolling stock is 

periodically overhauled. These include 26 MARC cars that have been or are scheduled to be 

refurbished between FY2005 and FY 2008. In addition, 23 locomotives are in the process of being 

overhauled and retrofitted to meet cleaner, federally required TIER standards. This is an ongoing 

effort that started in FY 2005 and is not expected to be completed until at least 2012. 

MTA Bus Purchases 

The Maryland Transit Administration (MTA) makes annual purchases of buses to replace, expand 

or upgrade the fleet. Buses over 12 years old are replaced. This purchase is made to prevent high 

out-of-service rates and reduce break down and repair problems. Bus replacements include new 

clean diesel as well as hybrid electric vehicles. The newer buses are much cleaner than the buses 

being replaced. In 2005, 125 buses were replaced; in 2006, 105 buses were replaced; and in 2007, 

100 buses were replaced. 

 

Locally Operated Transit Systems (LOTS) 

MTA provides funding to small jurisdictions and rural area systems including Anne Arundel, 

Baltimore, Carroll, Harford and Howard Counties. Regular small system buses and 

handicapped/senior ride vehicles are replaced, repaired, or expanded. The ridesharing program 

provides citizens with commute options. Funds are also used for outreach to companies in the 

counties to provide them with information on commuting options. 

 

Smart Card Implementation 

Implementation of Smart Card technology and fare collection equipment for the Baltimore Metro, 

bus, light rail, commuter bus and lots is being pursued by MTA. Smart card allows for quicker and 

seamless travel between different transit systems. Passengers are able to pay for travel throughout 

the state with the swipe of a card. This makes transit and high occupancy vehicle (HOV) travel 

more convenient for the traveler. 

 

Light Rail double tracking 

Installation of the double track was opened between North Avenue and Hunt Valley in 2006. The 

double track will enhance operational flexibility by eliminating delays and improve headways and 

service. The double track will make the service more attractive and thus increase HOV ridership. 

Baltimore Serious Area 8-Hour Ozone SIP Page 83
Port of Baltimore Initiatives 

In 2006, the Maryland Port Authority (MPA) partnered with Port stakeholders to oversee various 

physical and operational improvements to terminal gates. The purpose of the improvements was to 

expedite inbound and outbound vehicle traffic. A net benefit of these projects was overall 

reductions in idling time for heavy-duty diesel trucks and other vehicles visiting the terminals, 

resulting in reduced emissions. Since November 2006, MPA uses Ultra Low Sulfur Diesel Fuel 

blended with bio-diesel in all of its on-road as well as off-road diesel engines. This includes 

vehicles such as its cranes, fleet vehicles, stationary generators, fire pumps, and cargo handlingequipment. In the fall of 2006, MPA applied for an EPA grant to retrofit at least one ship-to-shore 

crane and several RTG cranes with Diesel Oxidation Catalysts. MPA understands that EPA will 

officially announce by the end of March 2007 that they will be awarded the grant. MPA annually 

exceeds EPA's 75% fleet vehicle alternative fuel purchasing requirements. To do so, MPA 

purchases bi-fuel (ethanol/gas) fleet vehicles. In addition, MPA purchased a hybrid (electric/gas) 

fleet vehicle in 2006. MPA performs outreach to employees on "ozone alert days" in order to reduce 

activities, such as vehicle fueling and combustion engine usage, which contribute to ozone 

pollution. 

Park and Ride Lots

The SHA and MdTA have built 43 lots in the Baltimore region since the 1970's. This does not 

include Baltimore City, which builds its own projects. The SHA has made substantial space 

additions to three Park and Ride lots in the Baltimore region and has built a 56-space new lot on 

Maryland Route 7. Other Park and Ride lots have been expanded or improved in the attainment 

areas adjacent to the Baltimore region as well as the Washington Metropolitan area. These lots 

serve to accommodate carpool based work trips into the Baltimore region. The benefits of the 

reduction in VMT and vehicle trips (VT) in the Baltimore region provides for a reduction in 

regional congestion and vehicular emissions. 

 

Landscaping and Reforestation 

Landscaping and reforestation can have a positive effect on water and air quality. In the Baltimore 

region reforestation and/or landscaping efforts have been made adjacent to the following roadway 

facilities since 2005: MD 2, MD 468, MD 665, MD 216, MD 100, US 40, I-695, I-83, and the MD 

43 extension. 

Additional Clean and Efficient Strategies Enacted or Under Development

Charm City Circulator 

http://www.charmcitycirculator.com/ 

The Circulator consists of four routes that run seven days a week using hybrid buses. Service is 

free. Air quality benefit calculations from this service started in 2009. The Transit Vehicle 

Purchases Project most recently added hybrid-electric buses to the Charm City Circulator to extend 

service to Fort McHenry National Monument and Historic Shrine. 

Hunt Valley Shuttle 

The Baltimore County Chamber of Commerce and the Hunt Valley Business Community are 

working to establish a bus shuttle between Hunt Valley and southern York County, PA, including 

the City of York. 

Baltimore Serious Area 8-Hour Ozone SIP Page 84
Kent Street Transit Plaza 

The Kent Street Transit Plaza and Pedestrian Corridor Project will expand bus ridership and safe 

access to the existing light rail system through design and construction of the Kent Street Plaza and 

Pedestrian Corridor from the Westport Light Rail Station to Annapolis Road. 

MARC East Baltimore Station 

A new station is planned for east Baltimore City in 2015. There is a potential tie-in with Baltimore 

City’s proposed Greektown pedestrian and transit project. 

Emergency Ride Home Program- proposed; the BRTB recommends moving forward with a 

program for the Baltimore region. (Note that the Washington, DC area already has Guaranteed 

Ride Home (GRH) as part of Commuter Connections.) 

Baltimore Collegetown Network (BCN) 

BCN operates a free bus service available to students registered at Goucher College, Towson 

University, Notre Dame of Maryland University, Loyola University Maryland, Johns Hopkins 

University, Maryland Institute College of Art, and Morgan State University. The Collegetown 

Shuttle, as it is known, is paid for by those institutions. 

BWI Airport Low Emission Vehicles 

The Maryland Aviation Administration’s (MAA’s) fleet of ground vehicles is extensive and 

consumes much fuel. To reduce the emissions associated with its vehicle fleet, MAA was a pioneer 

in encouraging the use of Compressed Natural Gas (CNG) vehicles. CNG vehicles offer air quality 

benefits, because they produce fewer emissions than gasoline-powered engines. 

U.S. Department of Housing and Urban Development (HUD) Sustainable Communities and 

Clean Fuels Program Grants 

Four federal grant programs were announced in August 2011: (1) clean fuel buses, (2) the Federal 

Transit Administration’s (FTA) Transit Investments for Greenhouse Gas and Energy Reduction 

(TIGGER) III program; (3) the U.S. Department of Transportation’s (USDOT) Transportation 

Investment Generating Economic Recovery Program (TIGER) III program; and (4) the 

HUD/EPA/USDOT Sustainability Grant Program. BMC will support grant applicants in the 

Baltimore region. These grant program projects are expected to help reduce emissions from on-road 

mobile sources. 

US 40 Carbon Neutral Corridor 

MDOT and Cambridge Systematics consultants are developing a comprehensive corridor vision that 

results in attaining smart growth, conservation and climate change goals where the net emissions 

from the corridor are significantly reduced. The corridor study area goes from Baltimore City to 

Aberdeen in Baltimore and Harford Counties. 

Clean Technology and Commute Alternatives 

http://www.baltometro.org/transportation-planning/transportation-improvement-program-2011-

2014 

A variety of projects have been implemented in the Baltimore region since 2007. Examples include 

hybrid fleet vehicles; hybrid replacement buses; hybrid taxis; and retrofits of fire trucks, medics, 

and shuttle buses. The projects have been implemented by private business, universities, and state 

and local governments.

Baltimore Serious Area 8-Hour Ozone SIP Page 85
9.0REASONABLY AVAILABLE CONTROL MEASURE (RACM) 

ANALYSIS 

Section 172(c)(1) of the Clean Air Act requires state implementation plans (SIPs) to include an 

analysis of Reasonably Available Control Measures (RACM). This analysis is designed to ensure 

that the Baltimore 8-hour Ozone Nonattainment Area is implementing all reasonably available 

control measures in order to demonstrate attainment with the 8-hour ozone standard on the earliest 

date possible. This chapter presents a summary of analyses conducted to determine whether the SIP 

includes all reasonably available control measures. Full details of the analysis are included in 

Appendix D. 

The Maryland Department of the Environment (MDE) has prepared this RACM analysis using two 

independently developed lists of potential control measures. The first list consists of the RACM 

analysis performed for the Washington, DC Region’s 8-hour ozone SIP. The MDE worked very 

closely with all the DC region’s jurisdictions in the development of the DC Region’s RACM 

analysis. Understanding that the adjacent Washington, DC non-attainment region is both extremely 

similar to the metropolitan Baltimore region and was also undertaking their RACM analysis, MDE 

incorporated the Washington, DC RACM criteria and analysis into this Baltimore SIP. 

The Washington, DC RACM analysis included a series of regional calls over several months to 

review over 200 suggested measures from numerous sources to create a master listing of measures. 

Each of over 200 measures was individually evaluated against established RACM criteria (the 

criteria are explained below). 

In addition to a careful review of the Washington, DC Region’s RACM analysis, during the fall of 

2006, the MDE also worked closely with the Baltimore Metropolitan Council (BMC) in developing 

a small list of potential transportation emission reduction measures. This analysis yielded a list of 

24 specific measures that could be implemented in the Baltimore Nonattainment Area for emission 

reduction purposes. Based on the criteria used for RACM, none of these 24 measures is to be 

considered RACM but these measures shall be kept on a short list of measures if the region needs 

additional reductions. 

 

At the completion of the RACM analysis it was determined that no measures met the criteria. 

 

9.1 ANALYSIS OVERVIEW AND CRITERIA 

 

The RACM requirement is rooted in Section 172(c)(1) of the Clean Air Act, which directs states to 

“provide for implementation of all reasonably available control measures as expeditiously as 

practicable”. In its 1992 General Preamble for implementation of the 1990 Clean Air Act 

Amendments (57 FR 13498) EPA explains that it interprets Section 172(c)(1) as a requirement that 

states incorporate in a SIP all reasonably available control measures that would advance a region’s 

attainment date. However, regions are obligated to adopt only those measures that are reasonably 

available for implementation in light of local circumstances. In the Preamble, EPA laid out 

guidelines to help states determine which measures should be considered reasonably available: 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 86
If it can be shown that one or more measures are unreasonable because emissions from the 

sources affected are insignificant (i.e. de minimis), those measures may be excluded from 

further consideration...the resulting available control measures should then be evaluated for 

reasonableness, considering their technological feasibility and the cost of control in the area 

to which the SIP applies...In the case of public sector sources and control measures, this 

evaluation should consider the impact of the reasonableness of the measures on the 

municipal or other government entity that must bear the responsibility for their 

implementation. 

 

In its opinion on Sierra Club v. EPA, decided July 2, 2002, the U.S. Court of Appeals for the DC 

Circuit upheld EPA’s definition of RACM, including the consideration of economic and 

technological feasibility, potential of the measures to cause substantial widespread and long-term 

adverse impacts, collective ability of the measures to advance a region’s attainment date, and 

whether an intensive or costly effort will be required to implement the measures. Consistent with 

EPA guidance and the U.S. District Court’s opinion, both the Baltimore and Washington DC 

regions have developed specific criteria for evaluation of potential RACM measures. Individual 

measures must meet the following criteria: 

 Will reduce emissions by the beginning of the 2008 ozone season (April 1, 2008) 

 Enforceable 

 Technically feasible 

 Economically feasible (proposed as a cost of $3,500-$5,000 per ton or less) 

 Would not create substantial or widespread adverse impacts within the region 

 Emissions from the source being controlled exceed a de minimis threshold, proposed as 0.1 

tons per day 

An explanation of these criteria is given in succeeding sections. 

9.1.1 Implementation Date 

 

EPA has traditionally instructed regions to evaluate RACM measures on their ability to advance the 

region’s attainment date. This means that implementation of a measure or a group of measures must 

enable the region to reduce ozone levels to the 84 ppb required to attain the eight-hour ozone 

standard at least one year earlier than expected. As the Baltimore region currently expects to reduce 

ozone levels to 84 ppb during the 2009 ozone season, any RACM measures must enable the region 

to meet the 84 ppb standard by April 1, 2008, the beginning of the 2008 ozone season. 

9.1.2 Enforceability 

 

When a control measure is added to a SIP, the measure becomes legally binding, as are any specific 

performance targets associated with the measure. If the state or local government does not have the 

authority necessary to implement or enforce a measure, the measure is not creditable in the SIP and 

therefore cannot be declared a RACM. A measure is considered enforceable when all state or local 

government agencies responsible for funding, implementation and enforcement of the measure have 

committed in writing to its implementation and enforcement. 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 87
In addition to theoretical enforceability, a measure must also be practically enforceable. If a 

measure cannot practically be enforced because the sources are unidentifiable or cannot be located, 

or because it is otherwise impossible to ensure that the sources will implement the control measure, 

the measure cannot be declared a RACM. One exception is voluntary measures, such as those 

implemented under EPA’s Voluntary Measures Guidance. 

 

9.1.3 Technological Feasibility 

 

All technology-based control measures must include technologies that have been verified by EPA. 

The region cannot take SIP credit for technologies that do not produce EPA-verified reductions. 

9.1.4 Economic Feasibility and Cost Effectiveness 

 

EPA guidance states that regions should consider both economic feasibility and cost of control 

when evaluating potential RACM measures. Therefore, the Baltimore region has specified a costeffectiveness threshold for all possible RACM measures. Measures for which the cost of 

compliance exceeds this threshold will not be considered RACM. 

 

In setting this threshold, the region took into consideration two major factors. First, EPA has issued 

guidance regarding the relationship between Reasonably Available Control Technology (RACT) 

and RACM. In its RACM analysis for the Dallas/Forth Worth nonattainment area, EPA states this: 

RACT is defined by EPA as the lowest emission rate achievable considering economic and 

technical feasibility. RACT level control is generally considered RACM for major sources.

 

In the Baltimore region, RACT installation costs are as low as approximately $3,500 per ton. The 

region proposes a threshold of $3,500-$5,000 for cost effectiveness. 

 

9.1.5 Substantial and Widespread Adverse Impacts 

 

Some candidate RACM measures have the potential to cause substantial and widespread adverse 

impacts to a particular social group or sector of the economy. Due to environmental justice 

concerns, measures that cause substantial or widespread adverse impacts will not be considered 

RACM. 

 

9.1.6 De Minimis Threshold 

 

In the General Preamble, EPA allows regions to exclude from the RACM analysis measures that 

control emissions from insignificant sources and measures that would impose an undue 

administrative burden. Under moderate area RACT requirements, the smallest major source subject 

to RACT emits 25 tpy, or approximately 0.1 tpd. 

Baltimore Serious Area 8-Hour Ozone SIP Page 88
Following these requirements and the precedent set by the San Francisco RACM analysis, the 

region will not consider control measures affecting source categories that produce less that 0.1 tpd 

NOx or VOC emissions. 

 

9.1.7 Advancing Achievement of 0.08 ppm (84 ppb) Standard 

 

In order for measures to be collectively declared RACM, implementation of the measures must 

enable the region to demonstrate attainment of the 0.08 ppm ozone standard one full ozone season 

earlier than currently expected. 

 

9.1.8 Intensive and Costly Effort 

 

When considered together, the implementation requirements of any RACM measure cannot be so 

great as to preclude effective implementation and administration given the budget and staff 

resources available to the Baltimore region. 

9.2 RACM MEASURE ANALYSIS 

 

9.2.1 Analysis Methodology 

 

The sources of strategies analyzed for the Baltimore region include the following: 

 Clean Air Act Section 108(f) measures (Transportation Control Measures) 

 Transportation Emissions Reduction Measures (TERMs) listed in recent Transportation 

Improvement Programs (TIPs) for the Metropolitan Baltimore and Washington DC regions 

 Measures identified through a review of the emission reduction strategies report prepared for 

the Baltimore Metropolitan Council 

 Measures considered in Washington, Atlanta and Houston RACM analyses 

 

These measures were then evaluated against the criteria discussed earlier in this chapter and 

documented in Appendix D. 

 

9.2.2 Analysis Results 

 

Appendix D provides lists (in tabular form) organized by source sector, of potential measures 

evaluated against the RACM criteria. Each specific RACM criterion was reviewed for each 

individual measure identified on the lists. 

 

Based on this analysis, none of the measures reviewed were identified as RACM for the Baltimore 

8-hour Ozone Nonattainment Area. 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 89
9.3 RACM DETERMINATION 

Though the measures listed in Appendix D did not meet the criteria for RACM, many of the 

measures are worthwhile measures that reduce emissions. These measures will be considered 

potential control measures for future SIPs prepared for the Baltimore region. 

References 

 

US EPA, “State Implementation Plans; General Preamble for the Implementation of Title I of the 

Clean Air Act Amendments of 1990”, (57 FR 13498), April 16, 1992. 

 

US EPA Region VI, “Reasonably Available Control Measures (RACM) Analysis for the 

Dallas/Fort Worth Ozone Nonattainment Area”, December 2000. 

 

Bay Area Air Quality Management District, Metropolitan Transportation Commission and 

Association of Bay Area Governments, “Bay Area 2001 Ozone Attainment Plan,” October 

24, 2001, Appendix C. 

 

 E.H. Pechan & Associates, Inc., “ Review of Emission Reductions Strategies”, 

 December 8, 2006. 

Baltimore Serious Area 8-Hour Ozone SIP Page 90
10.0 MOBILE SOURCE CONFORMITY 

Transportation conformity ("conformity") is a provision of the Clean Air Act that ensures that 

Federal funding and approval goes to those transportation activities that are consistent with air 

quality goals. Conformity applies to transportation plans and projects funded or approved by the 

Federal Highway Administration (FHWA) or the Federal Transit Administration (FTA) in areas that 

do not meet or previously have not met air quality standards for ozone, carbon monoxide, 

particulate matter, or nitrogen dioxide. 

In order to balance growing metropolitan regions and expanding transportation systems with the 

need to improve air quality, EPA established regulations ensuring that enhancements to existing 

transportation networks will not impair progress towards air quality goals. Under the Clean Air Act 

Conformity Regulations, transportation modifications in a nonattainment area must not impair 

progress made in air quality improvements. These regulations, published in EPA's Transportation 

Conformity rule on November 24, 1993 in the Federal Register and amended in a final rule signed 

on July 31, 1997, require that transportation modifications "conform" to air quality planning goals 

established in air quality SIP documents. The 1997 amendments were followed by further 

amendments in 2002, 2004, and more recent years since. 

In essence, this SIP submission includes mobile emissions budgets for nitrogen oxides (NOx) and 

volatile organic compounds (VOCs). These budgets, once found adequate by EPA, shall be used in 

all conformity documents for the Baltimore Nonattainment Area. In order for a transportation plan 

to “conform,” the estimated emissions from the transportation plan can not exceed the emissions 

budgets set via this SIP submission. If the estimated emissions are shown to exceed the budget then 

mitigation measures must be taken to ensure emissions will not exceed the emission budgets. 

Responsibility for Making a Conformity Determination 

The policy board of a Metropolitan Planning Organization (MPO), in consultation with the 

Maryland Department of Transportation (MDOT) and MDE, is responsible for formally making a 

conformity determination on the MPO’s transportation plans and transportation improvement 

programs (TIPs) prior to submittal to the FHWA and FTA for review. The EPA also may review 

and comment on proposed conformity determinations. 

If a particular transportation plan’s projected emissions exceed the mobile emissions budget, the 

MPO has a variety of mitigation options for reducing emissions. These may include but are not 

limited to specific transportation emission reduction measures such as High Occupancy Vehicle 

(HOV) lanes, transit enhancements, bicycle lanes, diesel retrofits, and idling reductions. 

The Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users 

(SAFETEA-LU) was enacted on August 10, 2005. Under this act, amendments were made to the 

transportation conformity rules (Section 6011 of the Act), which required states that have 

nonattainment areas like Maryland to revise their existing transportation conformity SIPs. 

Maryland submitted a revised transportation conformity SIP to USEPA in February of 2007. 

Baltimore Serious Area 8-Hour Ozone SIP Page 91
Because of changes mandated by SAFETEA-LU, conformity determinations have to be done at 

least every four years instead of the previous three years. 

When a positive conformity determination is not made according to the required frequency, or in 

the event that emission mitigation can’t be agreed upon, a nonattainment area is in conformity 

“lapse”. This means that federal transportation funds allocated to the state, which contains the 

lapsed nonattainment area, can only be used for the following kinds of projects: 

1. TCMs in Approved SIPs; 

2. Non-Regionally Significant Non-Federal Projects; 

3. Regionally Significant Non-Federal Projects - only if the project was approved by all 

necessary non-federal entities before the lapse. (See Approval of a Regionally Significant 

Non-Federal Project by a Non-Federal Entity later in this chapter.) 

4. Project phases (i.e., design, right-of-way acquisition, or construction) that received funding 

commitments or an equivalent approval or authorization prior to the conformity lapse. 

5. Exempt Projects - identified under 40 CFR §93.126and 40 CFR §93.127; and, 

6. Traffic Synchronization Projects - however, these projects must be included in subsequent 

regional conformity analysis of MPO's transportation plan/TIP under 40 CFR §93.128. 

The amount of federal funding a state receives is not reduced but such funds are restricted until the 

area can again demonstrate conformity. 

10.1 MOBILE EMISSIONS BUDGET & THE BALTIMORE REGION 

TRANSPORTATION CONFORMITY PROCESS 

 

Mobile source emissions in the long-range transportation plan known as the Baltimore Regional 

Transportation Plan (BRTP), and the shorter term Transportation Improvement Program cannot 

exceed the mobile emissions budget. The transportation plans are required to conform to the mobile 

budget established in the SIP for the short-term TIP years, as well as for the forecast period of the 

long-range plan, which must be at least twenty years. 

 

In the Baltimore region, modifications to the existing transportation network are advanced through 

the Baltimore Regional Transportation Board (BRTB) by state, regional and local transportation 

agencies through periodic updates to the BRTP and TIP. The TIP is updated annually for the 

Baltimore region and includes transportation modifications and improvements on a four-year 

program cycle. Pursuant to the conformity regulations, the TIP must contain analyses of the motor 

vehicle emissions estimates for the region resulting from the transportation improvements. These 

analyses must show that the transportation improvements in the TIP and the plan do not result in a 

deterioration of (“conform to”) the air quality goals established in the SIP. 

10.2 BUDGET LEVEL FOR ON-ROAD MOBILE SOURCE EMISSIONS 

As part of the development of the SIP, MDE, in consultation with the Baltimore Regional 

Transportation Board, establishes a mobile source emissions budget. This budget will be the 

benchmark used to determine if the region's long-range transportation plan (BRTP) and four-year 

transportation improvements program (TIP) conform to the SIP. Under EPA regulations, the 

Baltimore Serious Area 8-Hour Ozone SIP Page 92
projected mobile source emissions for 2012 (the region’s attainment ozone season) become the 

mobile emissions budgets for the region unless MDE takes actions to set other budget levels. 

 

Modeling and Data 

The 2012 mobile emissions inventories are calculated using the following models and tools: EPA’s 

MOVES and the Highway Performance Monitoring System (HPMS) model. A detailed explanation 

of the model and the emission estimating methodology can be found in Appendix E. 

 

Attainment Year Mobile Budgets 

The mobile emissions budgets for the 2012 attainment year are based on the projected 2012 mobile 

source emissions accounting for all mobile control measures. The mobile emissions budgets for the 

2012 attainment year, based upon the projected 2012 mobile source emissions, accounting for all 

the mobile control measures, are as follows: 

Table 10-1: 2012 Attainment Year Mobile Budgets for the Baltimore Nonattainment Area 

VOC (TPD) 40.2 

NOx (TPD) 93.5 

10.3 TRENDS IN MOBILE EMISSIONS 

The mobile emissions budgets for 2012 for VOCs and NOx reflect a continuation of a downward 

trend in mobile emissions over time. 

Baltimore Serious Area 8-Hour Ozone SIP Page 93
Mobile Emissions Trends

0.0

50.0

100.0

150.0

200.0

250.0

2002 2008 2011 2012

Year

Emissions (tons/day)

VOC

NOx

The steady reductions in mobile emissions are attributable largely to a series of increasingly 

stringent federal regulations requiring cleaner vehicles and fuels, including the federal Tier II 

regulations for motor vehicles. Trends toward reduced mobile emissions are occurring despite the 

negative effects of a shift toward the use of higher-emitting, less fuel-efficient sport utility vehicles 

instead of passenger cars and a steady increase in population, employment and vehicle miles 

traveled (VMT) within the Baltimore region. 

The trends of increasing population, employment, and VMT are expected to remain strong well 

beyond 2009. The regional cooperative forecasting process (from the 2004 Baltimore Regional 

Transportation Plan) predicts that from 2000 to 2030, the regional population will grow by 14% and 

employment will grow by 22%. Regional VMT is predicted to still outpace these increases over the 

same time period with a projected growth of 37% on an average weekday. These trends, however, 

will not reverse the expected decline in regional mobile emissions resulting from cleaner fuels and 

improved vehicle technology. The Tier II passenger vehicle standards and regulations on emissions 

from heavy-duty diesel vehicles and fuels are expected to produce further dramatic reductions in 

VOC and NOx emissions as vehicles are replaced and retrofitted over the next 20 years. It is 

important to keep in mind, however, that despite cleaner fuels and improved vehicle technology, the 

relationship between land use planning, transportation, and air quality is important for long-term air 

quality goals. 

Baltimore Serious Area 8-Hour Ozone SIP Page 94
11.0 SERIOUS AREA PLAN COMMITMENTS 

 

Achieving the results shown in this Plan requires a commitment to implement the regulatory 

measures upon which the plan is based. Maryland is taking action to implement regional and local 

measures to effectively reduce ozone transport throughout the Baltimore and Washington 

Nonattainment Areas. Tables 11-1 and 11-2 provide information on the implementation of each 

measure. 

 

11.1 SCHEDULES OF ADOPTED CONTROL MEASURES 

 

Table 11-1: 

Maryland Schedule of Adopted Control Measures 

Baltimore, Washington DC, and Cecil County Nonattainment Areas 

Control Measure Regulation Number Effective Date 

Federally Mandated Measures 

High Tech Inspections & 

Maintenance 

11.14.08 1/2/1995 

Stage II Vapor Recovery Nozzle 26.11.24 2/15/1993 

Federal Tier I Vehicle Standards and 

new Car Evaporative Standards 

40 CFR part 86 Model Year 1994-1996; Evap 

Stds. 1996 

Tier 2 Motor Vehicle Emission 

Standards 

65 FR 6698 

 

2/10/2000 

Non-CTG RACT See Table 11-2 - 

Phase II Gasoline Volatility Controls 03.03.03.05 10/26/1992 

EPA Non-Road Gasoline Engines 

Rule 

40 CFR parts 90 and 91 12/3/1996 

EPA Non-Road Diesel Engines Rule 40 CFR Part 9 et al. Model Year 2000-2008 

depending on engine size 

State NOx RACT Requirements 26.11.29.08 5/10/1993 

EPA Nonroad Spark Ignition Marine 

Engine Rule 

40 CFR Parts 89, 90, 91 1998 Model Year 

EPA Large Spark Ignition Engines 

Rule 

40 CFR Parts 89, 90, 91, 

94, 1048, 1051, 1065, and 

1068 

11/8/2002 

Federal Programs 

Baltimore Serious Area 8-Hour Ozone SIP Page 95
Control Measure Regulation Number Effective Date 

Reformulated Surface Coatings 63 FR 48849, 64 FR 

34997, 65 FR 7736 

9/11/1998, 6/30/1999, 

2/16/2000 

National Volatile Organic 

Compound Emission Standards for 

Consumer Products 

63 FR 48819 9/11/1998 

National Low Emissions Vehicle 

Program 26.11.20.04 3/22/1999 

Emissions Controls for Locomotives 63 FR 18998 6/15/1998 

Heavy-Duty Diesel Engine Rule 63 FR 54694 12/22/1997 

State and Local Measures 

Reformulated Gasoline (on-road) Federal - local opt-in 1/1/1995 

Reformulated Gasoline (off-road) Federal - local opt-in 1/1/1995 

Surface Cleaning/Degreasing for 

Machinery/Automobile Repair 

26.11.19.09 6/5/1995 

Landfill Regulations 26.11.19.20 3/9/1998 

Seasonal Open Burning Restrictions 26.11.07 5/22/1995 

Stage I Expansion 26.11.13.04C 4/26/1993 

Expanded Point Source Regulations 

to 25 tpy 

26.11.19.01B(4) 5/8/1995 

Graphic Arts Controls 26.11.19.11 & .18 6/5/1995 & 11/7/1994 

Auto and Light Duty Truck Coating 

Operations 

26.11.19.23 5/22/1995 

Control of VOC Emissions from 

Vehicle Refinishing 

26.11.19.23 5/22/1995 

Portable Fuel Containers Rule: 

Phase I 

26.11.13.07 1/21/2002 

Architectural and Industrial 

Maintenance Coatings Rule 

26.11.33 3/29/2004 

Reformulated Consumer Products 

Rule: Phase I 

26.11.32 8/18/2003 

Control of VOC Emissions from 

Cold and Vapor Degreasing 

26.11.19.09 6/5/1995 

Maryland Healthy Air Act 26.11.27 Emergency Regulations 

effective 1/18/2007 - 

Permanent Regulations 

effective 7/16/2007 

Industrial Adhesives and Sealants 

Rule* 

26.11.35 4/21/2008, and amendment 

(permanent regulations) 

effective 6/1/2009 

Baltimore Serious Area 8-Hour Ozone SIP Page 96
Control Measure Regulation Number Effective Date 

Portable Fuel Containers Rule: 

Phase II* 

26.11.13.07 6/18/2007 

Reformulated Consumer Products 

Rule: Phase II* 

26.11.32 6/18/2007 

Regional Control Measures 

NOx Phase II Controls 26.11.27 & .28 

26.11.29 & 30 

10/18/1999 

Table 11-2: 

Maryland Non-CTG RACT 

Baltimore and Washington Nonattainment Areas 

 

Overall requirement in COMAR 26.11.19.02G effective 4-26-93 (20: Md. R 726) 

The following case-by-case RACT regulations have been adopted to ensure consistency. 

 

 

RACT Regulation Regulation 

Number 

Effective 

Date 

MD Register 

 

Plastic Parts Coating 

 

26.11.19.07E 

 

6-5-95 

 

22:11 Md R 823 

Definition of Gasoline to include JP-4 

 

26.11.13.01 

 

8-11-97 

 

24:16 Md R. 

1161 

 

Printing on Plastic 

 

26.11.19.07F 

 

9-8-97 

 

24:18 Md R 

1298 

 

Aerospace Coating Operations 

 

26.11.19.13-1 

 

9-22-97 

 

24:19 Md R 

1344 

 

Yeast Manufacturing 

 

26.11.19.17 

 

11-7-94 

 

21:22 Md R 

1879 

 

Expandable Polystyrene Operations 

 

26.11.19.19 

 

7-3-95 

 

22:13 Md R 970 

 

Commercial Bakery Ovens 

 

26.11.19.21 

 

7-3-95 

 

22:13 Md R 970 

 

Vinegar Generators 

 

26.11.19.22 

 

8-11-97 

 

24:16 Md R 

1161 

Baltimore Serious Area 8-Hour Ozone SIP Page 97
 

RACT Regulation Regulation 

Number 

Effective 

Date 

MD Register 

 

Leather Coating 

 

26.11.19.24 

 

8-11-97 

 

24:16 Md R 

1161 

 

Explosives and Propellant 

Manufacturing 

 

26.11.19.25 

 

8-11-97 

 

24:16 Md R 

1161 

 

Reinforced Plastic Manufacturing 

 

26.11.19.26 

 

8-11-97 

 

24:16 Md R 

1162 

 

Marine Vessel Coating Operations 

 

26.11.19.27 

 

10-20-97 

 

24:21 Md R 

1453 

11.2 STATIONARY SOURCE THRESHOLDS 

Under the “moderate” classification for the 8-hour ozone standard, the permit threshold is 50 tons 

per year VOC and 100 tons per year NOx. In order to prevent backsliding Maryland is required to 

maintain the Baltimore NAA permit threshold at 25 tons per year for both VOC and NOx. 

Baltimore Serious Area 8-Hour Ozone SIP Page 98
12.0 CONTINGENCY MEASURES 

12.1 PURPOSE OF CHAPTER 

This chapter demonstrates that the Baltimore Nonattainment Area meets the requirements for SIP 

contingency measures related to both Reasonable Further Progress (RFP) and to the attainment of 

the ozone standard. If implemented, the contingency measures discussed in this chapter would result 

in reductions in addition to those required to demonstrate RFP (discussed in Chapter 5) and in 

addition to those that have been taken into account in the attainment demonstration (discussed in 

Chapters 5-7). Contingency measures ensure that if the Baltimore Nonattainment Area fails to 

achieve the required RFP reductions by the RFP milestone year, or fails to attain the ozone standard 

by the attainment year, additional reductions will occur without further state or federal action. 

12.2 CONTINGENCY REQUIREMENTS 

Section 172(c)(9) of the CAA and EPA’s Phase 2 Rule require that nonattainment areas include 

contingency measures in their RFP and attainment SIPs. If a state receives a notification from EPA 

that a nonattainment area within its borders has failed to achieve the level of reductions 

demonstrated in the RFP SIP by the milestone year, or has failed to attain the standard by the 

attainment date, the area must be able to implement contingency measures within one year after 

EPA’s notice. 

The RFP contingency and the attainment contingency must each provide for reductions equivalent 

to at least 3% of the 2002 RFP Adjusted Base Year VOC emissions inventory.23 The contingency 

reductions are in addition to the reductions required to demonstrate RFP and in addition to the 

reductions taken into account in the attainment demonstration. 

12.3 RFP CONTINGENCY 

As discussed in Chapters 5-7, MDE is meeting the RFP requirement to reduce emissions by 27 

percent for the years 2002 to 2012 (15 percent RFP for the years 2002 to 2008, 9 percent RFP for 

the years 2008 to 2011, 3 percent RFP for the years 2011 to 2012) through a combination of 

reductions of NOx and VOCs. 

To satisfy the contingency requirement, MDE must be able to demonstrate that if the Baltimore area 

fails to achieve the required RFP reductions, without further state or federal action, an additional 

3% reduction could be achieved from control measures not already taken in account in calculation 

of the 27% RFP reduction. 

According to EPA’s interpretation of this requirement, the RFP contingency may be met by 

showing reductions in the 2012 RFP milestone year of at least 30% by 2012 (27% RFP + 3% RFP 

 

23 The RFP Adjusted Base Year Inventory is based on the MD 2002 Base Year Inventory adjusted for RFP purposes, as 

discussed in detail in Chapters 5-7. 

Baltimore Serious Area 8-Hour Ozone SIP Page 99
contingency).24 As demonstrated in Chapter 7, Table 7-3 and reproduced with additional 

information in Table 12-1 below, the Baltimore area has demonstrated reductions significantly 

greater than the 27% reductions needed to meet RFP requirements and the additional 3% reductions 

needed to meet the contingency requirements. Therefore, the Baltimore Nonattainment Area has 

met the RFP contingency requirement. 

Table 12-1: 

Baltimore Nonattainment Area 

Comparison of 2012 Target Inventory plus 3% Contingency and 2012 Controlled Inventories 

Description VOC NOx

(a) 2012 Target Levels 220.38 328.49 

(b) RFP 3% Contingency Reductions 

(1.5% of VOC & NOx 2012 Target Levels in (a)) 3.31 4.93 

(c) 2012 Target Levels with Additional 

RFP Contingency (a)-(b) 217.07 323.56 

(d) 2012 Controlled Emissions 199.90 232.88 

12.4 ATTAINMENT CONTINGENCY 

EPA will assess whether the Baltimore Nonattainment Area has attained the standard, presumably 

based on monitored ozone readings for 2010 - 2012. If the area is not meeting the standard based 

on readings for the 3-year period, EPA may issue a notification of failure to attain. The notification 

will trigger a requirement for MDE to implement contingency reductions within one year of the 

notification. For purposes of this contingency analysis, MDE is assuming that EPA would issue the 

notice in June 2013, and that the contingency measures would need to be in place by June 2014. 

Therefore, to meet the attainment contingency requirement, MDE must identify control measures 

that will achieve additional reductions in emissions after 2012 and by June 2014 from control 

measures that will be effective without any further state or federal action. One year from the date of 

notification, the identified contingency measures must be fully implemented. This means that the 

contingency measures must provide emission reductions in the 2014 timeframe to meet the 

contingency requirements. 

The amount of additional reductions that must be achieved in order to meet the attainment 

contingency requirement is 3% of the 2002 RFP Adjusted Base Year VOC emissions. The amount 

of reductions is shown below. 

Table 12-2: Required Attainment Contingency 

 2002 RFP Adjusted Base Year Inventory 

(TPD) 

3% of 2002 VOCs = 

Required Contingency Reduction 

 VOC NOx 

BNAA 258.69 369.69 7.76 

 

24 U.S. EPA Memorandum from Michael H. Shapiro to Region 1 through 10 Air Directors, Guidance on Issues Related 

to 15% Rate-of-Progress Plans, August 23, 1993. 

Baltimore Serious Area 8-Hour Ozone SIP Page 100
While the required reductions (3%) are calculated as a percentage of the 2002 VOC emissions, NOx 

reductions can be used as a direct substitute for up to 90% of the required reductions. Therefore, 

only 0.3% of the reductions achieved by the contingency measures must be VOCs; this equates to 

0.78 TPD in the BNAA. 

Table 12-3: Minimum VOC Reductions Required for Attainment Contingency 

Pollutant Total Reductions 

Needed for Contingency 

Pollutant 

Percentage 

Contingency Amount 

per Pollutant 

(tpd) 

VOC 7.76 10% 0.78 

NOx 7.76 90% 6.98 

MDE will meet this attainment contingency requirement by taking credit for emission reductions 

that will be achieved from the existing federal on-road mobile source control measures such as Fuel 

Standards and Heavy-Duty Engine Standards, and from the Maryland Low-Emission Vehicle 

(LEV) Program. These measures will continue to provide substantial VOC and NOx emission 

reductions through 2012 (and beyond) as newer, less-polluting vehicles replace the older fleet. 

In addition some emission control strategies listed to meet the 2012 target level are expected to 

result in more emission reductions than are needed to meet the requirements. If other measures fail 

to meet expected reductions, the excess from the following measures will be used to make up the 

difference: 

 On-road mobile 

 Nonroad Mobile 

 Ozone Transport Commission (OTC) - Portable Fuel Container Phase 1 and Phase 2 

 OTC - Architectural Surface Coatings 

 OTC – Commercial and Consumer Products 

 Railroad Locomotives Tier 2 

12.5 CONCLUSIONS 

As shown in Table 12-4 below, which is a combination of Tables 5-5, 6-2, and 7-2 with RFP 

contingency information added, the Baltimore Nonattainment Area has met the RFP contingency by 

demonstrating that the reductions of VOC and NOx projected by 2012 are significantly greater than 

the 30% reduction that is required (27% for RFP and 3% for RFP contingency). For the attainment 

contingency, the reductions of VOC and NOx that will be achieved from the on-road mobile source 

control measures already in effect are significantly greater than reductions needed to meet the 3% 

attainment contingency requirement. 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 101
Table 12-4: Contingency Measure Calculations 

VOC Target Level for 2012 Milestone 

Baltimore Nonattainment Area 

Emissions in Tons per Day 

 Formula 

A 2002 Base Year Inventory 485.97

B Biogenic Emissions 223.20

C 2002 Rate-of Progress Base Year Inventory A - B 262.77

D FMVCP/RVP Reductions Between 2002 and 2008 4.08

E 2002 Adjusted Base Year Inventory Calculated Relative to 2008 C - D 258.69

F Reduction Ratio 0.0800

G Emissions Reductions Required Between 2002 and 2008 E * F 20.70

H Target Level for 2008 [TL(2008)] C - D - G 238.00

Reclassification / Bump Up 

I FMVCP/RVP Reductions Between 2008 and 2011 0.29

J 2002 Adjusted Base Year Inventory Calculated Relative to 2011 I - J 237.71

K Reduction Ratio 0.0600

L Emissions Reductions Required Between 2008 and 2011 J * K 14.26

M Target Level for 2011 [TL(2011)] J - L 223.73

 

N FMVCP/RVP Reductions Between 2011 and 2012 0.00

O 2002 Adjusted Base Year Inventory Calculated Relative to 2012 M - N 223.73

P Reduction Ratio 0.0150

Q Emissions Reductions Required Between 2011 and 2012 P * O 3.36

R Target Level for 2012 [TL(2012)] O - Q 220.38

S RFP Contingency (3% Total: 1.5% VOC/1.5% Nox) 3.31

T Attainment Contingency Target Level with minimum VOC reductions 0.78

U Contingency Target Level R-(S + T) 216.30

 Emission Level Obtained 2012 199.90

Baltimore Serious Area 8-Hour Ozone SIP Page 102
NOx Target Level for 2012 Milestone 

Baltimore Nonattainment Area 

Emissions in Tons per Day 

 Formula 

A 2002 Base Year Inventory 371.47

B Biogenic Emissions 0.00

C 2002 Rate-of Progress Base Year Inventory A – B 371.47

D FMVCP/RVP Reductions Between 2002 and 2008 1.78

E 2002 Adjusted Base Year Inventory Calculated Relative to 2008 C – D 369.69

F Reduction Ratio 0.0700

G Emissions Reductions Required Between 2002 and 2008 E * F 25.88

H Target Level for 2008 [TL(2008)] C - D - G 343.81

Reclassification / Bump Up 

I FMVCP/RVP Reductions Between 2008 and 2011 0.00

J 2002 Adjusted Base Year Inventory Calculated Relative to 2011 I – J 343.81

K Reduction Ratio 0.0300

L Emissions Reductions Required Between 2008 and 2011 J * K 10.31

M Target Level for 2011 [TL(2011)] J – L 333.49

 

N FMVCP/RVP Reductions Between 2011 and 2012 0.18

O 2002 Adjusted Base Year Inventory Calculated Relative to 2012 M – N 333.32

P Reduction Ratio 0.0150

Q Emissions Reductions Required Between 2011 and 2012 P * O 5.00

R Target Level for 2012 [TL(2012)] O - Q 328.49

S RFP Contingency (3% Total: 1.5% VOC/1.5% Nox) 4.93

T Attainment Contingency Target Level with minimum VOC reductions 6.98

U Contingency Target Level R-(S + T) 316.58

 Emission Level Obtained 2012 232.88

Baltimore Serious Area 8-Hour Ozone SIP Page 103
13.0 ATTAINMENT MODELING DEMONSTRATION 

The 8-hour Ozone Standard Attainment Modeling Demonstration analyzes the potential of the 

Baltimore NAA to achieve attainment of the 8-hour ozone standard by June 15, 2013. The 

attainment modeling demonstration is comprised of the following five sections: 

13.1 – Modeling Study Overview 

13.2 – Domain and Data Base Issues 

13.3 – Model Performance Evaluation 

13.4 – Attainment Demonstration 

13.5 – Procedural Requirements 

13.1 MODELING STUDY OVERVIEW 

13.1.1 Background and Objectives 

Since the Baltimore 8-Hour Ozone Nonattainment Area (NAA) did not attain the 1997 8-hour 

ozone standard by its 2009 attainment date, EPA reclassified the Baltimore NAA from a “moderate” 

to a “serious” NAA. Baltimore is accordingly required to demonstrate attainment of the 8-hour 

ozone standard by 2012 using photochemical modeling and weight-of-evidence analyses. Chapter 

14 contains all the weight-of-evidence analyses supporting the Baltimore NAA’s attainment of the 

8-hour ozone standard. 

The objective of the photochemical modeling study is to enable the MDE to analyze the efficacy of 

various control strategies, and to demonstrate that the measures adopted as part of the State 

Implementation Plan (SIP) will result in attainment of the 8-hour ozone standard by June 15, 2013. 

The modeling exercise predicts future year 2012 air quality conditions based on the worst episodes 

in the base year 2002, and applies control measures to demonstrate the effectiveness of new control 

measures in reducing air pollution. 

For the reason previously mentioned, the Ozone Transport Commission (OTC), on behalf of the 

Ozone Transport Region (OTR) member states, including Maryland, undertook a photochemical 

modeling study to demonstrate compliance with the 8-hour ozone NAAQS. The 8-hour ozone 

attainment modeling study was directed by the OTC Modeling Committee, which consisted of the 

following workgroups: OTC Photochemical Workgroup, OTC Meteorological Modeling 

Workgroup, OTC Emissions Inventory Development Workgroup, and the OTC Control Strategy 

Workgroup. 

The OTC Air Directors served on the OTC Oversight Committee and provided oversight of the 

process. 

Table 13-1 identifies all jurisdictions within the 8-hour ozone Baltimore NAA and Figure 13-1 

provides a graphical representation of the 8-hour ozone Baltimore NAA.

Baltimore Serious Area 8-Hour Ozone SIP Page 104
Table 13-1: Jurisdictions within the 8-Hour Ozone Baltimore NAA 

Area Maryland 

Counties Classification Attainment Date 

Baltimore NonAttainment Area 

Anne Arundel 

Baltimore 

Baltimore City 

Carroll 

Harford 

Howard 

Serious June 2013 

Baltimore, MD 

Non-Attainment Area 

Figure 13-1: 8-Hour Ozone Baltimore NAA 

The photochemical model selected for the attainment modeling demonstration was the EPA 

Models-3/Community Multi-scale Air Quality (CMAQ) modeling system, which is a “OneAtmosphere” photochemical grid model capable of addressing ozone at a regional scale and is 

considered one of the preferred models for regulatory modeling applications. The modeling 

analyses set forth in this report have been conducted in accordance with the Guidance on the Use of 

Models and Other Analyses for Demonstrating Attainment of Air Quality Goals for Ozone, PM2.5, 

and Regional Haze (Draft 3.2- September 2006). 

Baltimore Serious Area 8-Hour Ozone SIP Page 105
13.1.2 Relationship to Regional Modeling Protocols 

The state of Maryland is a member of the OTC and, along with other member OTC states, was able 

to coordinate the modeling analyses performed for the Baltimore NAA with the regional modeling 

analysis conducted by the OTC Modeling Committee. 

The lead agency for coordinating the running of the CMAQ model and performing the modeling 

runs for the OTC was the New York State Department of Environmental Conservation (NYSDEC). 

Modeling centers for the OTC included the NYSDEC, the University of Maryland at College Park 

(UMD), the Northeast States for Coordinated Air Use Management (NESCAUM), the New Jersey 

Department of Environmental Protection (NJDEP) and the Virginia Department of Environmental 

Quality (VADEQ). The lead modeling agency for coordinating the running of the CMAQ model 

for the OTC and performing the modeling runs was the NYSDEC, but member states of the OTC, 

within the frame-work of the OTC, managed the modeling project collectively. All OTC modeling 

inventories were provided by the Mid-Atlantic Regional Air Management Association (MARAMA) 

and developed, updated, and shared among the OTC states’ modeling centers. 

Installation of the CMAQ model at all participating modeling centers was completed and diagnostic 

procedures were run successfully. The CMAQ model was benchmarked against other modeling 

platforms across the OTR to ensure accurate results. The OTC Modeling Committee oversaw the 

modeling effort and reported to the OTC Oversight Committee through regular briefings and 

presentations, and offered additional information in cases where specific technical decisions had 

policy implications. MDE was a member of the various OTC committees to ensure that the 

Maryland ozone modeling protocol followed the same analyses being conducted by the OTC. 

Provided in Appendix F-1 is the Baltimore NAA ozone modeling protocol. 

13.1.3 Conceptual Description 

EPA recommends that a conceptual description of an area’s ozone problem be developed prior to 

the initiation of any air quality modeling study. A “conceptual description” is a qualitative way of 

characterizing the nature of an area’s non-attainment problem. Within the conceptual description of 

a particular modeling exercise, it is recommended that the specific meteorological parameters that 

influence air quality be identified and ranked in importance based on qualitative information. 

NESCAUM prepared the conceptual description for this study for the OTR member states’ use. 

The conceptual description document, The Nature of the Ozone Air Quality Problem in the Ozone 

Transport Region: A Conceptual Description (NESCAUM, October 2006), is provided in Appendix 

F-2. This document provides the conceptual description of the ozone problem in the OTR states, 

consistent with the EPA’s guidance. 

13.2 DOMAIN AND DATA BASE ISSUES 

13.2.1 Episode Selection 

Baltimore Serious Area 8-Hour Ozone SIP Page 106
The procedures for selecting 8-hour ozone modeling episodes seek to achieve a balance between the 

science and regulatory needs and constraints. Modeling episodes, once selected, influence technical 

and policy decisions for many years. Both the direct and implicit procedures used in selecting 

episodes warrant full consideration. 

The rationale for the selection of 2002 meteorology as input to the air quality simulations includes a 

qualitative analysis (Ryan and Piety 2002) and a quantitative analysis (Environ 2005). These 

documents are provided in Appendix F-3. 

Recent research has shown that model performance evaluations and the response to emissions 

controls need to consider modeling results over long time periods; in particular, full synoptic cycles 

or even full ozone seasons. Based on this factor, the entire ozone season was simulated for the 2012 

SIP modeling runs (May 1 to September 30). As a result, the total number of days examined for the 

complete ozone season far exceeds EPA recommendations, and provides for better assessment of 

the simulated pollutant fields. 

 

13.2.2 Size of the Modeling Domain 

In defining the modeling domain, one must consider the location of the local urban area, the 

downwind extent of the elevated ozone levels, the location of large emission sources, and the 

availability of meteorological and air quality data. The domain or spatial extent to be modeled 

includes as its core the NAA. Beyond this, the domain includes enough of the surrounding area 

such that major upwind sources fall within the domain and emissions produced in the NAA remain 

within the domain throughout the day. 

The boundaries of the OTC modeling domain are provided in Appendix F-4. This domain covers 

the Northeast region, including the northeastern, central and southeastern U.S. as well as 

southeastern Canada. The final SIP modeling analysis utilized this modeling domain. 

13.2.3 Horizontal Grid Size 

The OTC platform provided the basic platform for the Baltimore NAA modeling analysis and 

utilized a coarse grid continental United States domain with a 36 km horizontal grid resolution. The 

CMAQ domain is nested in the Pennsylvania State University/National Center for Atmospheric 

Research (PSU/NCAR) Mesoscale Meteorological Model (MM5) domain. A larger MM5 domain 

was selected for the MM5 simulations to provide a buffer of several grid cells around each 

boundary of the CMAQ 36 km domain. This was designed to eliminate any errors in the 

meteorology from boundary effects in the MM5 simulation at the interface of the MM5 model. A 

12 km inner domain was selected to better characterize air quality in OTR and surrounding 

Regional Planning Organization (RPO) regions. Appendix F-5 contains the horizontal grid 

definitions for the MM5 and CMAQ modeling domains. 

Baltimore Serious Area 8-Hour Ozone SIP Page 107
13.2.4 Vertical Resolution 

The vertical grid used in the CMAQ modeling was primarily defined by the MM5 vertical structure. 

The MM5 model employed a terrain following coordinate system defined by pressure. The layer 

averaging scheme adopted for CMAQ is designed to reduce the computational cost of the CMAQ 

simulations. Only the uppermost layers of the CMAQ domain were coalesced. All layers in the 

planetary boundary layer were left undisturbed in moving from the MM5 to the CMAQ simulation. 

This ensures that the near-surface processes that affect air pollution the most are faithfully 

represented in CMAQ, while the meteorological systems that are driven by upper-level winds are 

allowed to develop properly in MM5. The effects of layer averaging have a relatively minor effect 

on the model performance metrics when compared to ambient monitoring data. 

Appendix F-6 contains the vertical layer definitions for the MM5 and CMAQ modeling domains. 

13.2.5 Initial and Boundary Conditions 

The objective of a photochemical grid model is to estimate the air quality, given a set of 

meteorological and emissions conditions. When initializing a modeling simulation, the exact 

concentration fields are not known in every grid cell for the start time. Therefore, typically 

photochemical grid models are started with clean conditions within the domain and allowed to 

stabilize before the period of interest is simulated. In practice, this is accomplished by starting the 

model several days, called spin-up time, prior to the period of interest. 

The winds move pollutants into, out of, and within the domain. The model handles the movement of 

pollutants within the domain and out of the domain. An estimate of the concentration of pollutants 

at the edge of the domain and therefore the quantity of pollutants moving into the domain is needed. 

These are called boundary conditions. The 12 km grid boundary conditions were extracted from the 

36 km CMAQ simulation. To estimate the boundary conditions for the modeling study, boundary 

conditions for the outer 36 km domain were derived every three hours from an annual model run 

performed by researchers at Harvard University using the GEOS-CHEM global chemical transport 

model (Moon and Byun 2004, Baker 2005). The influence of boundary conditions was minimized 

by using a 15-day spin-up period, which is sufficient to establish pollutant levels that are 

encountered in the eastern U.S. Additional information on the extraction of boundary conditions is 

provided in Appendix F-7. 

13.2.6 Meteorological Model Selection and Configuration 

The Pennsylvania State University/National Center for Atmospheric Research (PSU/NCAR) 

Mesoscale Meteorological Model (MM5) version 3.6 was used to generate the annual 2002 

meteorology for the OTC modeling analysis. The MM5 model is a non-hydrostatic, prognostic 

meteorological model routinely used for urban- and regional-scale photochemical regulatory 

modeling studies. Professor Da-Lin Zhang (UMD) performed the MM5 modeling in consultation 

with the NYSDEC and MDE staff. 

Baltimore Serious Area 8-Hour Ozone SIP Page 108
A more detailed description and performance evaluation of the MM5 modeling results are provided 

in Appendix F-8. Based on model validation and sensitivity testing, the MM5 configurations 

provided in Appendix F-9 were selected. 

 

13.2.7 Emissions Model Selection and Configuration 

The Sparse Matrix Operator Kernel Emissions (SMOKE) Emissions Processing System was 

selected for the OTC modeling analysis. SMOKE is principally an emissions processing system, 

and not a true emissions inventory preparation system in which emissions estimates are simulated 

from ‘first principles’. This means that, with the exception of mobile and biogenic sources, its 

purpose is to provide an efficient, modern tool for converting emissions inventory data into the 

formatted, hourly, mapped emissions files required for a photochemical air quality model. 

Inside the OTR, the emissions inventories prepared for the modeling analyses were developed 

through a coordinated effort between the OTR states and the Mid-Atlantic Northeast Visibility 

Union (MANE-VU) Regional Planning Organization (RPO). 

The 2002 emissions were first generated by the individual OTR states. These inventories were then 

assembled and processed through the MANE-VU RPO. The 2002 emissions for non-OTR areas 

within the modeling domain were obtained from other RPOs for their corresponding areas. 

These RPOs included the Visibility Improvement State and Tribal Association of the Southeast 

(VISTAS), the Midwest Regional Planning Organization (MRPO) and the Central Regional Air 

Planning Association (CENRAP). These emissions were then processed by the NYSDEC using the 

SMOKE (Version 2.1) processor to provide inputs for the photochemical model. Wherever possible, 

the mobile source emission inventories (in vehicle miles traveled, or “VMT” format) were replaced 

with Source Classification Code (SCC)-specific county level emissions to more accurately reflect 

actual emissions for a typical ozone season day. 

The emissions inventories included a base case (2002), which serves as the “parent” inventory off 

which all future year inventories (i.e., 2012) are based. The future year emissions inventories 

include emissions growth due to projected increases in economic activity as well as emissions 

reductions due to implementation of control measures. 

A detailed description of all SMOKE input files, such as area, mobile, fire, point and biogenic 

emissions files, and the SMOKE model configuration are provided in Appendix F-10. 

13.2.8 Air Quality Model Selection and Configuration 

EPA’s Models-3/Community Multi-scale Air Quality (CMAQ) modeling system was selected for 

the attainment demonstration primarily because it is a “one-atmosphere” photochemical grid model 

capable of addressing ozone on a regional scale and is considered one of the preferred models for 

regulatory modeling applications. The model is also recommended by the Guidance on the Use of 

Models and Other Analyses for Demonstrating Attainment of Air Quality Goals for Ozone, PM2.5, 

and Regional Haze (Draft 3.2- September 2006). 

Baltimore Serious Area 8-Hour Ozone SIP Page 109
Baltimore Serious Area 8-Hour Ozone SIP Page 110

The CMAQ configuration is provided in Appendix F-11. 

13.2.9 Quality Assurance 

All air quality, emissions, and meteorological data were reviewed to ensure completeness, accuracy, 

and consistency before proceeding with modeling. Any errors, missing data or inconsistencies, 

were addressed using appropriate methods that are consistent with standard practices. All modeling 

was benchmarked through the duplication of a set of standard modeling results across different 

modeling centers. 

Quality Assurance (QA) activities were carried out for the various emissions, meteorological, and 

photochemical modeling components of the modeling study. Emissions inventories obtained from 

the RPOs were examined to check for errors in the emissions estimates. When such errors were 

discovered, the problems in the input data files were corrected and the models were run again. 

The MM5 meteorological model and CMAQ air quality model inputs and outputs were plotted and 

examined to ensure sufficiently accurate representation of the observed data in the model-ready 

fields, and temporal and spatial consistency and reasonableness. Both MM5 and CMAQ underwent 

operational and scientific evaluations in order to facilitate the quality assurance review of the 

meteorological and air quality modeling procedures, and these evaluations are discussed in greater 

detail in other sections of this SIP and the appendices. 

13.3 MODEL PERFORMANCE EVALUATION 

13.3.1 Overview 

There are many aspects of model performance. This section will focus primarily on the methods and 

techniques recommended by EPA for evaluating the performance of the air quality model. It should 

be noted that other parts of the modeling process, the emissions and meteorology, also undergo an 

evaluation. In the interest of keeping this section concise, though, the air quality model is the 

primary focus. 

The first step in the modeling process is to verify the model’s performance in terms of its ability to 

predict ozone in the right locations and at the right levels. To do this, model predictions for the base 

year simulation are compared to the ambient data observed in the historical episode. This 

verification is a combination of statistical and graphical evaluations. If the model appears to be 

predicting ozone in the right locations for the right reasons, then the model can be used as a 

predictive tool to evaluate various control strategies and their effects on ozone. The purpose of the 

model performance evaluation is to assess the accuracy with which the model predicts ozone levels 

observed in the historical episode. Then CMAQ’s predictions of future year air quality are put in 

the appropriate context when CMAQ performance and predictions are used to inform future policy 

decisions. 
The results of a model performance evaluation were examined prior to using CMAQ’s results to 

support the attainment demonstration. The performance of CMAQ was evaluated using both 

operational and diagnostic methods. Operational evaluation refers to the model’s ability to replicate 

observed concentrations of ozone and/or precursors (surface and aloft), whereas diagnostic 

evaluation assesses the model’s accuracy with respect to characterizing the sensitivity of ozone to 

changes in emissions (i.e., relative response factors). 

The NYSDEC conducted a performance evaluation of the 2002 base case CMAQ simulation (May 

15-September 30) on behalf of the OTR member states. Appendix F-12 provides comprehensive 

operational and diagnostic evaluation results, including spreadsheets containing the assumptions 

made to compute statistics. Highlights of this evaluation are provided in the following sections. 

13.3.2 Diagnostic and Operational Evaluation 

The issue of model performance goals for ozone is an area of ongoing research and debate. To 

evaluate model performance, EPA recommends that several statistical metrics be calculated for air 

quality modeling. Two of the common metrics that are most often used to assess performance are 

the mean normalized gross error and the mean normalized bias. The mean normalized gross error 

parameter provides an overall assessment of model performance and can be interpreted as precision, 

and the mean normalized bias parameter measures a model's ability to reproduce observed spatial 

and temporal patterns and can be interpreted as accuracy. EPA suggests the following criteria: a 

mean normalized gross error (MNGE) of < 35%, and a mean normalized bias (MNB) of < ±15% 

above a threshold of 40-60 ppb. These results are presented in Table 13-2 for the Baltimore NAA 

and in Tables 13-3 and 13-4 on a monitor-by-monitor basis averaged over all days for the 40 ppb 

and 60 ppb thresholds. Figure 13-2 shows the location of the monitors in the Baltimore NAA. 

Table 13-2: Baltimore NAA Statistics for 8-hour Ozone

Location 

Ozone Cutoff 

Threshold 

(ppb) 

Mean 

Normalized 

Gross Error 

(MNGE) 

(%) 

Mean 

Normalized Bias 

(MNB) 

(%) 

40 12.94 -0.99 Baltimore, MD NAA 60 12.49 -4.41 

Table 13-3: Individual Site Statistics for 8-hour Ozone Using 40 ppb Cutoff

AIRS ID Site Name County State MNGE 

(%) 

MNB 

(%) 

240030014 Davidsonville Anne Arundel MD 12.49 -5.11 

240051007 Padonia Baltimore MD 11.60 -1.34 

240053001 Essex Baltimore MD 14.60 3.62 

240130001 South Carroll Carroll MD 12.31 1.33 

Baltimore Serious Area 8-Hour Ozone SIP Page 111
AIRS ID Site Name County State MNGE 

(%) 

MNB 

(%) 

240251001 Edgewood Harford MD 13.63 -2.50 

240259001 Aldino Harford MD 12.35 -4.29 

Table 13-4: Individual Site Statistics for 8-hr Ozone Using 60 ppb Cutoff 

AIRS ID Site Name Jurisdiction State MNGE 

(%) 

MNB 

(%) 

240030014 Davidsonville Anne Arundel MD 12.31 -9.14 

240051007 Padonia Baltimore MD 10.11 -5.38 

240053001 Essex Baltimore MD 15.80 1.39 

240130001 South Carroll Carroll MD 10.02 -2.50 

240251001 Edgewood Harford MD 14.06 -5.35 

240259001 Aldino Harford MD 12.36 -7.12 

 

Baltimore, MD 

Non-Attainment Area 

Ozone Monitor 

Figure 13-2: Locations of Ozone Monitors in the Baltimore NAA 

Baltimore Serious Area 8-Hour Ozone SIP Page 112
The following statistics for the OTR domain have also been provided in Appendix F-12. 

1. Archive file containing 8-hour average observed and predicted ozone organized by state. 

2. Observed and predicted composite diurnal variations of selected species, including but not 

limited to ozone at SLAMS/NAMS sites; ozone at CASTNet and other sites; VOC species 

such as ethene, isoprene, and formaldehyde; and gas phase compounds such as CO, NO and 

NO2. 

3. Statistical evaluation of daily maximum 8-hour ozone at SLAMS/NAMS sites and 

CASTNet/other sites; statistics are computed using two different thresholds for observed 

daily maximum ozone of 40 and 60 ppb. Statistics are computed by date (all sites on a given 

day) and by site (one site over all days). 

4. Statistical evaluation of daily maximum 8-hour ozone at SLAMS/NAMS sites that fall 

within non-attainment counties; statistics are computed by non-attainment area. 

5. Statistical evaluation of daily average CO, NO, NO2, and SO2 at SLAMS/NAMS and other 

sites; statistics are computed by date and by site. 

6. Statistical evaluation of daily average ethene, isoprene, and formaldehyde at 

SLAMS/NAMS and other sites; statistics are computed by date and by site. 

7. Plots of composite time series for daily max 8-hour ozone, root mean square error and mean 

bias for illustrative purposes. 

8. Maps of daily 8-hour maximum predicted ozone across the modeling domain, compared 

with actual observations. 

13.3.3 Summary of Model Performance 

The CMAQ model was employed to simulate ozone for the 2002 season (May through 

September).25 A comparison of the temporal and spatial distributions of ozone and its precursors 

was conducted for the study domain, with additional focus placed on performance in the Baltimore 

NAA. 

The CMAQ model performance for surface ozone is quite good with low bias and error. Model 

performance is generally consistent from day to day. The results of the 2002 ozone season show 

that the modeling system tends to over-predict minimum concentrations and slightly under-predict 

peak concentrations. The over-prediction of minimum concentrations is not of great regulatory 

concern since attainment tests are based on the application of relative response factors to daily peak 

concentrations. Prediction of minimum concentrations, though, is still important to appropriately 

model regional transport and nighttime ozone removal processes in order to accurately estimate 

peak concentrations. 

The model performance for the Baltimore NAA averaged over all stations and all days meets the 

guidelines suggested by EPA. Applying those criteria to individual days is a much more stringent 

 

25 Note that the Maryland ozone season changed to April through October, in 2004; see 40 CFR 58, Appendix D, Table 

D-3. 

Baltimore Serious Area 8-Hour Ozone SIP Page 113
test that is not required by EPA. If, however, those long-term average standards are applied to daily 

performance, those criteria for acceptable model performance are met on most individual days as 

well. 

No significant differences in model performance for ozone and its precursors were encountered 

across different areas of the OTR. While there are some differences in the spatial data among subregions, there is nothing to suggest a tendency for the model to respond in a systematically different 

manner between regions. Examination of the statistical metrics by sub-region confirms the absence 

of significant performance problems arising in one area but not in another, building confidence that 

the CMAQ modeling system is operating consistently across the full OTR domain. 

The evaluations discussed above show that the modeling system is doing a good job of 

appropriately estimating 8-hour average surface ozone throughout the OTR and in the Baltimore 

NAA. This confidence in the modeling results allows the modeling system to be used to support the 

development of emissions control scenarios and, more generally, the Baltimore NAA 8-hour Ozone 

SIP. 

Also, as stated previously, the model performance for the 2002 ozone season meets all EPA 

guidelines and thus demonstrates that the modeling platform is appropriate for modeling emissions 

controls scenarios for the Baltimore NAA SIP. At the same time it must be remembered that 

CMAQ has been evaluated by using measures that reflect its ability to represent average conditions 

instead of its ability to respond to changes in emissions. Thus it is likely that although CMAQ has 

met the traditional performance measures as stated in EPA guidance, it may in fact under-predict 

the magnitude of ozone changes resulting from the modeling of various control measures. This 

means future year (i.e., 2012) modeling results should be viewed not in the traditional sense as 

being exact, but should be seen as an upper limit. 

 

13.4 ATTAINMENT DEMONSTRATION 

13.4.1 Overview 

The 8-hour ozone standard attainment demonstration analyzes the potential of the Baltimore NAA 

to achieve attainment of the 8-hour ozone standard. The demonstration of the achievement of the 8-

hour ozone standard is based on both the CMAQ modeling results and a number of weight-ofevidence analyses (provided in Chapter 14) that support the attainment modeling results. Details of 

the CMAQ modeling are provided in the following sections. 

13.4.2 Modeling Attainment Test 

 

The modeled attainment test applied at each monitor was performed using the following equation: 

(DVF)I = (RRF)I (DVB)I 

Baltimore Serious Area 8-Hour Ozone SIP Page 114
Where: 

(DVB)I = the baseline concentration monitored at site I, in ppb 

(RRF)I = the relative response factor, calculated near site I 

(DVF)I = the estimated future design value, in ppb, for the time attainment is required. 

The future design value for each monitor in the Baltimore NAA is provided in Table 13-5 and in 

Figure 13-3. 

 

Table 13-5: Modeling Attainment Test Using EPA Preferred Methodology 

AIRS ID Site Name County State DVB RRF DVF 

240030014 Davidsonville Anne Arundel MD 98.0 0.797 78 

240051007 Padonia Baltimore MD 88.7 0.816 72 

240053001 Essex Baltimore MD 91.3 0.838 76 

240130001 South Carroll Carroll MD 88.7 0.816 72 

240251001 Edgewood Harford MD 100.3 0.804 80 

240259001 Aldino Harford MD 97.0 0.793 76 

Baltimore Serious Area 8-Hour Ozone SIP Page 115
Figure 13-3: Baltimore NAA 8-Hour Ozone Base Year (2002) and Future Year (2012) Design 

Values 

Current design values were calculated using the EPA approved method of averaging the three 

design value periods that include the baseline inventory year. Specifically, the average design value 

was calculated using the 2000-2002, 2001-2003, and 2002-2004 periods. 

In the event that there were less than five years of available data at a monitoring site the following 

procedure was used: 

1. 3 years of data - The current design value was based on a single design value. 

2. 4 years of data - The current design value was based on an average of two design value 

periods. 

3. Less than 3 years of data – The site was not used in the attainment test. 

A 3x3 array of grid cells surrounding each monitor was used in the modeled attainment test as 

recommended by EPA for 12 km grid resolution modeling to calculate RRFs. 

Baltimore Serious Area 8-Hour Ozone SIP Page 116
The predicted 8-hour daily maximum ozone concentrations from each modeled day were used in the 

modeled attainment test, with the nearby grid cell with the highest predicted 8-hour daily maximum 

ozone concentration with baseline emissions for each day considered in the test, and the grid cell 

with the highest predicted 8-hour daily maximum ozone concentration with the future emissions for 

each day in the test. 

The RRFs used in the modeled attainment test were computed by taking the ratio of the mean of the 

8-hour daily maximum predictions in the future, to the mean of the 8-hour daily maximum 

predictions with baseline emissions, over all relevant days, as defined below. 

The following rules were applied to determine the number of days and the minimum threshold at 

each ozone monitor: 

1. If there were 10 or more days with daily maximum 8-hour average modeled ozone > 85 

ppb, an 85 ppb threshold was used. 

2. If there were less than 10 days with daily maximum 8-hour average modeled ozone > 85 

ppb, the threshold was reduced in 1 ppb increments to as low as 70 ppb, until there were 

10 days in the mean RRF calculation. 

3. If there were less than 10 days but more than 5 days with daily maximum 8-hour average 

modeled ozone > 70 ppb, then all days > 70 ppb were used. 

4. No RRF calculations were performed for sites with less than 5 days > 70 ppb. 

Provided in Appendix F-13 is additional information on the RRF and the modeled attainment test. 

13.4.3 Unmonitored Area Analysis 

 

An “unmonitored area analysis” using model adjusted spatial fields was performed. The basic steps 

of this process were as follows: 

1. Interpolated ambient ozone design value data to create a set of spatial fields. 

2. Adjusted the spatial fields using gridded model output gradients (base year values). 

3. Applied gridded model RRFs to the model adjusted spatial fields. 

4. Determined if any unmonitored areas are predicted to exceed the NAAQS in the 

future. 

Recommended EPA guidance was utilized in the unmonitored area analysis. 

Provided in Figure 13-4 is a map showing the spatially interpolated extent of 8-hour ozone above 

the NAAQS in the Baltimore NAA based on a future case (2012) modeling simulation. 

Baltimore Serious Area 8-Hour Ozone SIP Page 117
2012 Predicted 8-Hour Ozone Design Value (ppb)

Figure 13-4: Spatially Interpolated Extent of the 8-Hour Ozone in the Baltimore NAA Using 

Predicted 2012 Design Values 

In Figure 13-4 the clear areas within the Baltimore NAA indicate the areas that will be below the 8-

hour NAAQS of 85 ppb. Figure 13-4 clearly demonstrates that all areas within the Baltimore NAA 

are predicted to be in attainment of the 8-hour ozone NAAQS by 2012. 

13.4.4 Emissions Inventories 

For areas with an attainment date of no later than June 15, 2013, the emission reductions need to be 

implemented no later than the beginning of the 2012 ozone season. A determination of attainment 

will likely be based on air quality monitoring data collected in 2010, 2011, and 2012. Therefore, the 

year to project future emissions should be no later than the last year of the three-year monitoring 

period; in this case, 2012. 

Baltimore Serious Area 8-Hour Ozone SIP Page 118
The 2002 base year emissions inventory was projected to 2012 using standard emissions projection 

techniques discussed previously and in Appendix F-14. The 2012 inventories developed by 

MANE-VU were used in the attainment demonstration. 

Emission inventory guidance documents were followed for developing projection year inventories 

for point, area, mobile, and biogenic emissions. These procedures addressed projections of spatial, 

temporal, and chemical composition change between the base year and projection year. 

The OTC selected several control strategies for evaluation in the attainment demonstration. These 

were selected from groups of strategies developed by the technical subcommittees responsible for 

identifying and developing the regulations and/or control measures. 

Consideration was given to maintaining consistency with control measures likely to be implemented 

in other RPOs. Technology-based emission reduction requirements mandated by the Clean Air Act 

were also included in projecting future year emissions. 

Provided in Appendix F-14 is additional information on the emissions used in future year modeling. 

13.4.5 Summary and Conclusions of Attainment Demonstration 

The results of the future year (2012) modeling simulation indicate that the maximum 8-hour ozone 

design value for the Baltimore NAA will be in the range of 80 ppb at the Edgewood, MD ozone 

monitor. This translates into an 8-hour ozone design value reduction of approximately 20 ppb from 

2002 to 2012. The significance of 80 ppb is that it falls below 82 ppb; according to EPA guidance, 

this means that only a basic supplemental analyses should be completed to confirm the outcome of 

the modeled attainment test that the future year (2012) design value will be less than the 8-hour 

ozone NAAQS. 

The weight-of-evidence demonstration (Chapter 14) is meant to be a basic supplemental analysis 

that when combined with the modeling demonstration, presents significant evidence that the future 

year (2012) design value for the Baltimore NAA will be well below the 8-hour ozone NAAQS. 

Presented in Figures 13-5 and 13-6 are two maps of the Baltimore NAA 8-hour ozone design 

values, for 2002 (the base year), and the predicted 8-hour ozone design values for the future year 

2012, respectively. In each map of the Baltimore NAA, clear areas have 8-hour ozone design 

values below the NAAQS and the colored areas have design values that are equal to or exceed the 

8-hour ozone NAAQS. These two design value maps clearly demonstrate the trend of improved air 

quality through 2012 and attainment of the 8-hour ozone NAAQS for the Baltimore region. 

Presented in Figure 13-7 are the 2002 8-hour ozone design values and the predicted 8-hour ozone 

design values for future year 2012 for each ozone monitor in the Baltimore NAA. These design 

values demonstrate that the trend of improved air quality continues into 2012 and attainment of the 

8-hour ozone NAAQS. 

Baltimore Serious Area 8-Hour Ozone SIP Page 119
Based on a combination of the future year (2012) modeling simulation results and the basic 

supplemental weight-of-evidence (Chapter 14) analyses there is over whelming evidence to 

demonstrate that the Baltimore NAA will attain the 8-hour ozone NAAQS by June 15, 2013. 

Figure 13-5: Spatially Interpolated Extent of the 8-Hour Ozone Within the Baltimore NAA 

Using 2002 Base Year Design Values 

Baltimore Serious Area 8-Hour Ozone SIP Page 120
Figure 13-6: Spatially Interpolated Extent of the 8-Hour Ozone Within the Baltimore NAA 

Using 2012 Predicted Future Year Design Values 

Baltimore Serious Area 8-Hour Ozone SIP Page 121
Figure 13-7: Baltimore NAA 8-Hour Ozone Base Year (2002) and Predicted Future Year 

(2012) Design Values 

Baltimore Serious Area 8-Hour Ozone SIP Page 122
13.5 PROCEDURAL REQUIREMENTS 

13.5.1 Reporting 

Documents, technical memorandums, and data bases developed in this study are available for 

distribution as appropriate. This report contains the essential methods and results of the conceptual 

model, episode selection, modeling protocol, base case model development and performance 

testing, future year and control strategy modeling, quality assurance, weight of evidence analyses 

(Chapter 14), and calculation of 8-hr ozone attainment via EPA’s relative response factor (RRF) 

methodology. 

13.5.2 Data Archival and Transfer of Modeling Files 

All relevant data sets, model codes, scripts, and related software required by any project participant 

necessary to corroborate the study findings (e.g., performance evaluations and control strategy runs) 

will be provided in an electronic format approved by the OTC Modeling Committee within the 

framework of the OTC. The OTC Modeling Committee has archived all modeling data relevant to 

this project. Transfer of data may be facilitated through the combination of a project website and 

the transfer of large databases via overnight mail. Database transfers will be accomplished using an 

ftp protocol for smaller datasets, and the use of IDE and Firewire disk drives for larger data sets. 

 

Baltimore Serious Area 8-Hour Ozone SIP Page 123
GENERAL REFERENCES 

Ryan, W.F., Piety, C. (2002) Summary of 2002 Pollution Episodes in the Mid-Atlantic. The 

Pennsylvania State University Department of Meteorology, State College, Pennsylvania and the 

University of Maryland Department of Meteorology, College Park, Maryland. 

Stoeckenius, T., Kemball-Cook, S. (2005) Ozone Episode Classification Project for Ozone 

Transport Commission (Task 2b), ENVIRON International Corporation, Novato, California. 

Moo, N. and D. Byun (2004) A Simple User’s Guide For “geos2cmaq” Code: Linking CMAQ with 

GEOS-CHEM. Version 1.0. Institute for Multidimensional Air Quality Studies (IMAQS). 

University of Houston, Houston, Texas. 

Baker, K. (2005) http://www.ladco.org/tech/photo/present/ozone.pdf

EPA GUIDANCE DOCUMENTS 

Guidance on the Use of Models and Other Analyses for Demonstrating Attainment of Air Quality 

Goals for Ozone, PM2.5, and Regional Haze (Draft 3.2- September 2006). U.S. Environmental 

Protection Agency, Research Triangle Park, North Carolina. 

Baltimore Serious Area 8-Hour Ozone SIP Page 124
14.0 WEIGHT OF EVIDENCE ATTAINMENT DEMONSTRATION 

The approach that MDE has taken to Maryland’s weight of evidence attainment demonstration is 

that of supplemental data analysis and modeling. These techniques provide a favorable indication 

that the Baltimore NAA will successfully attain the 8-hour ozone NAAQS in 2012. 

14.1 AMBIENT AIR MONITORING MEASUREMENTS AND TRENDS 

Measurements from surface monitoring stations provide the most fundamental indication of air 

quality improvement in the Baltimore NAA. Basic trends of ozone from the network of monitors 

show continuously improving air quality in Maryland and the Baltimore NAA with respect to multiyear design values, annual exceedance day counts, 24-hour daily peak concentrations, single-hour 

concentrations, warm weather days when ozone is usually highest, and finally ozone precursor 

trends. 

14.1.1 The Ambient Monitoring Network 

MDE operates a relatively dense network of ozone monitoring stations, which has enabled the 

collection of high resolution ozone data on various scales of time and space. Figure 14-1 shows 

maps of the ambient ozone monitoring network for Maryland, the Mid-Atlantic, and the Eastern 

U.S. Comparing the spatial density of monitoring sites on a wider domain of the Mid-Atlantic 

region shows that Maryland has no large expanses without monitors, like Virginia, West Virginia, 

and Pennsylvania. An even larger perspective over the entire eastern U.S. reveals that Maryland is 

covered by one of the more dense monitoring networks due to the required monitoring associated 

with the cluster of large metropolitan areas extending from Richmond, VA through New York, NY. 

The Code of Federal Regulations requires four ozone sites for a metropolitan statistical area of 

greater than 10 million people for an 8-hour ozone non-attainment area (40 CFR 58 Appendix D 

§4.1). MDE currently has seven ozone sites deployed in the Baltimore NAA, which is currently 

classified by EPA to be in “moderate” non-attainment. Due to logistical reasons, slight changes are 

made in the deployment of sites over the years, such as the unavoidable relocation of the Fort 

Meade monitoring site due to the U.S. military’s need for additional space on the grounds of the 

Fort Meade military post. MDE was fortunate to find a new location for the site at Beltsville, where 

interagency collaborations and opportunities for long-term studies are more viable. In addition, a 

site was located in Baltimore City at the Furley Elementary School Recreational Center in August 

2006. On the whole, the number of sites has remained relatively constant. 

Baltimore Serious Area 8-Hour Ozone SIP Page 125
Panel A – Maryland Ozone Network 

Panel B – Mid-Atlantic Ozone Network Panel C – Eastern U.S. Ozone Network 

Figure 14-1: Maps of the 2012 Ozone Monitoring Sites 

There are 17 ozone monitoring sites in the state of Maryland, a dense network for a relatively small 

state.

Baltimore Serious Area 8-Hour Ozone SIP Page 126
 

14.1.2 Ozone Trends 

Ozone concentrations exhibit an improving air quality trend on multiple temporal scales. Perhaps 

the simplest regulatory measure of improving air quality is the downward trend in 8-hour ozone 

design values for the sites in Maryland. Design values offer the benefit of a multi-year metric, 

which removes the statistical bias of single high values by taking the fourth highest value of three 

consecutive years and averaging those values together. Figure 14-2 displays the decreasing trend of 

8-hour ozone design values in Maryland. The trend is a good fit to the data with an R2 of ~0.6 and a 

slope of -0.8 ppb / year. The decrease in ozone design values between 2003 and 2004 reflects the 

disproportionate benefit of the NOx SIP Call, as this is when the majority of regional NOx controls 

were put in place on electric generating units (EGU’s). This trend of decreasing ozone design 

values is expected to continue through 2012, as the Maryland Healthy Air Act (HAA), the first 

phase of which started in 2009, will significantly reduce Maryland EGU NOx and SO2 emissions. 

112

109

113113112114

109

119

132

125

115

107105

110

107

110

107106104103

95

91

93 94

91

87

106107

103 104

y = -0.8492x + 119.93

R2

 = 0.5728

85

95

105

115

125

135

198019821984198619881990199219941996199820002002200420062008

8-Hour Ozone Design Value (ppb) Figure 14-2: Trend in 8-hour Ozone Design Values per Year for all Maryland Sites 

The downward trend in 8-hour ozone concentrations on an annual basis is highlighted in Figure 14-

3 by showing the number of 8-hour ozone exceedance days per year. This trend is also a good fit 

with an R2

 of ~0.5 and a steeper declining slope of –1.4 days/year. Since 2002, an average of 

approximately 16 days per year, or approximately 2 weeks, have experienced 8-hour ozone 

concentrations  85ppb; this is a sharp contrast to the 2 months’ worth of exceedance days which 

existed in the 1980s. 

Baltimore Serious Area 8-Hour Ozone SIP Page 127
4646

67

41

545255

59

3033

54

25

55

4342

3335

54

45

20

29

41

1110

28

20

26

15

3

y = -1.4355x + 59.933

R2

 = 0.5532

0

10

20

30

40

50

60

70

80

19821984198619881990199219941996199820002002200420062008

Number of Days

Figure 14-3: Trend in 8-hour Ozone Exceedance Days per Year for all Maryland Sites 

The declining trend is an indicator of improving air quality. 

The temporal scale trend next reviewed is the daily scale. Average daily peak 8-hour ozone is 

shown in Figure 14-4. In order to show a clearer picture of the trends without the noise of shortterm fluctuations, the data are grouped in four-year bins. The methodology of choosing bins is 

carried out in reverse chronological order, beginning with the first four-year bin, 2006-2009. The 

scientific consensus is that ozone concentrations in the eastern U.S., outside of large urban areas, 

are NOx-limited.26 As a result, reductions in region-wide NOx emissions (NOx SIP Call) should

reduce the overall background ozone concentrations. Local emissions and photochemistry will still 

lead to short-term spikes in ozone, often  85 ppb, but these spikes will occur on top of a lower 

base-level of ozone. The magnitude of each individual ozone spike should also have a reduced 

amplitude from the base-level. Such a change in the base-level of ozone was created by the NO

 

x

SIP Call and is demonstrated in Figure 14-4. 

26 Ryan, W.F., “Local Ozone Forecasting and the NOx SIP Call Rule”, EPA National Air Quality Conference, Orlando, 

FL, 2007. 

Baltimore Serious Area 8-Hour Ozone SIP Page 128
0

20

40

60

80

100

120

Feb Mar Apr May Jun Jul Aug Sep Oct Nov

8-hour Ozone (ppb) .

1990-1993 1994-1997 1998-2001

2002-2005 2006-2009

Figure 14-4: Trends in Average Daily Peak 8-hour Ozone for all Maryland Sites Binned by 

Four-year Periods 

The red arrow indicates improving air quality shown by the decreasing trend of average daily 

peak 8-hour ozone. The solid lines are monthly averages. 

Continuing in reverse chronological order, each of the prior bins also consisted of a four-year period 

for the sake of consistency. The most important feature of Figure 14-4 is the steady decline in the 

trend of each bin, indicated by the red arrow. The part of the summer when peak ozone 

concentrations occur (June-August) is exactly when the greatest benefit is seen with reductions in 

the daily peak 8-hour ozone. The improving trend in 1998-2001 is partially due to meteorology 

because the summers of 2000 and 2001 were not conducive to photochemical formation. 

Temperatures were cooler than normal, precipitation was more prevalent, and the synoptic scale 

systems rarely created long-lived high pressure centers over the southeastern U.S. which typically 

plays a large role in high ozone episodes. The improving trend in 2002-2005 shows another marked 

decrease in ozone values, a sign of the valuable impact of the NOx SIP Call. 

Not only have ozone concentrations been steadily declining during the part of the summer when 

ozone production is greatest, but ozone concentrations have also been steadily declining during the 

part of each day when ozone production is greatest. Being a photochemical pollutant, ambient 

ozone reaches its peak concentrations during the afternoon when the sun angle is high and 

temperatures are at their warmest. Figure 14-5 shows the diurnal trend in ozone from 1993 to 2009. 

The years are binned by 3-year rolling averages in order to eliminate the noise of hourly 

fluctuations present in the raw data. The steady progression from each rolling average to the next 

shows an improvement of air quality. The red arrow indicates the decline of ozone concentrations. 

Baltimore Serious Area 8-Hour Ozone SIP Page 129
The last three rolling averages experienced a distinct decline in magnitude of hourly ozone after the 

NOx SIP Call. 

The red arrow indicates improving air quality shown by the decreasing trend of peak mid-day 

hourly concentrations. 

Figure 14-5: Trend in Diurnal Ozone by 3-year Rolling Averages for All Maryland Sites from 

the Summers (April 1 – October 31) of 1993 through 2009 

The approach to trends thus far has focused entirely on the ozone concentrations themselves. A 

more comprehensive look at ozone trends must also consider meteorology and precursors. Ozone is 

a photochemical pollutant and as such, it is highly dependent upon meteorological conditions. 

14.1.3 Temperature Adjusted Ozone Trend 

The data shown in Figure 14-6 provide insight into the trend of 8-hour ozone with respect to 

temperature. 

Baltimore Serious Area 8-Hour Ozone SIP Page 130
y = -1.3389x + 28.63

R2

 = 0.6955

0

10

20

30

40

50

60

70

19821984198619881990199219941996199820002002200420062008

Number of Days .

-30

-20

-10

0

10

20

30

40

Difference .

Number of Days greater than or equal to 90 Degrees F at BWI

Number of 8-hour Ozone Exceedence Days in Maryland

Difference (Number of Exceedence Days - Number of 90 Degree Days)

Linear Trend of Difference

y = -1.3389x + 28.63

R2

 = 0.6955

0

10

20

30

40

50

60

70

19821984198619881990199219941996199820002002200420062008

Number of Days .

-30

-20

-10

0

10

20

30

40

Difference .

Number of Days greater than or equal to 90 Degrees F at BWI

Number of 8-hour Ozone Exceedence Days in Maryland

Difference (Number of Exceedence Days - Number of 90 Degree Days)

Linear Trend of Difference

Figure 14-6: Maryland Air Quality: Days above 90F and Ozone Exceedances, 1982-2008 

Improving air quality in Maryland is shown by the downward linear trend (black line) of the 

difference between (blue line) the number of 8-hour ozone exceedance days per year (green 

bars) and the number of days with a daily maximum temperature > 90°F per year at BWI 

(red bars). The time period is 1981-2009. 

Temperature is the single strongest environmental predictor of ozone concentrations; as such there 

has historically been a strong correlation between the number of 8-hour ozone exceedance days per 

year and the number of days with a daily maximum temperature > 90F per year at BWI. In fact, in 

the early 1980’s the number of ozone exceedance days was typically double the number of 90F 

days. This statistic has steadily changed, though, so that in 2006 the ratio was the exact opposite 

with the number of 90F days double the number of exceedance days. The trend in the difference 

between the two counts (black line) has an R2

 of approximately 0.7 and a downward slope of –1.3. 

Despite stable numbers of 90F days, ambient ozone concentrations continue to experience a 

downward trend reflecting improvements in air quality. 

Baltimore Serious Area 8-Hour Ozone SIP Page 131
14.1.4 Ambient Ozone Precursor Trend 

As described in Chapter 2, the precursors to ozone formation include VOCs and NOx. VOCs are 

somewhat difficult to depict in terms of simple trends because the list of VOCs is very large. MDE 

collects 56 species of VOCs as part of the Photochemical Assessment Monitoring Sites (PAMS) 

network and a separate list (with some overlap) of 61 Toxic VOCs. VOC measurements have 

uniformly experienced declines in concentrations since 1994 due to the reformulated gasoline rule 

and hydrocarbon reductions for ozone. They have also received some associated benefits from 

restrictions on CFC (chlorofluorocarbon) emissions since the 1990s. NOx on the other hand, is 

more simply analyzed and it is widely available. A given percent reduction of NOx should result in 

an equal percent reduction of ozone. NOx is measured by the same trace gas instrumentation used 

to simultaneously measure ambient NO and NO2. NO2 is commonly measured to show compliance 

with the NO2 NAAQS. Figure 14-7 displays the decreasing trend of NOx for the Baltimore NAA 

since 1993. 

0

10

20

30

40

50

60

70

80

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

Hour (EST)

NOx (ppb)

1993-1995 1994-1996 1995-1997 1996-1998 1997-1999

1998-2000 1999-2001 2000-2002 2001-2003 2002-2004

2003-2005 2004-2006 2005-2007 2006-2008 2007-2009

Figure 14-7: Trend in Diurnal NOx by 3-year Rolling Averages for All Sites in Maryland 

during the Summers (April 1 – October 31) of 1993 through 2009 

Instrument calibration occurs during the data gap at 2:00 AM Eastern Standard Time (EST). 

Baltimore Serious Area 8-Hour Ozone SIP Page 132
14.1.5 Supplemental Modeling 

On July 6, 2011, the EPA released the final version of the Transport Rule, also know as the CrossState Air Pollution Rule (CSAPR). The CAMx air quality model runs for the rule were documented 

in the Air Quality Modeling Final Rule Technical Support Document (June 2011), and can be found 

here: http://www.epa.gov/airtransport/pdfs/AQModeling.pdf. 

The CSAPR modeling was performed for several emissions cases: 

1. 2005 base year, 

2. 2012 “no CAIR” case, 

3. 2014 “no CAIR or CSAPR” case, and 

4. 2014 “with CSAPR” case. 

The 2005 average design value (Avg DV) was calculated by using a five-year weighted average of 

the three 3-year averages (2003–2005, 2004–2006, and 2005–2007) and was used to determine 

whether a monitor was in nonattainment for the CSAPR. 

Based on the 2012 and 2014 modeling results, all monitors within the Baltimore NAA demonstrated 

compliance with the 1997 8-hour ozone NAAQS. The CSAPR modeling results are shown in Table 

14-1. 

Table 14-1 CSAPR Average Design Value Modeling Results for Baltimore NAA Monitors 

Monitor ID 2012 

“without CAIR” 

(ppb) 

2014 

“without CAIR or 

CSAPR” 

(ppb) 

2014 

“with 

CSAPR” 

(ppb) 

Edgewood 240251001 84.4 82.5 82.3 

Davidsonville 240030014 78.6 77.6 77.3 

Essex 240053001 78.7 77.3 77.1 

South Carroll 240130001 74.2 72.2 72.0 

Aldino 240259001 80.0 76.4 76.2 

Padonia 240051007 70.0 68.3 68.2 

Note: 

The Furley Elementary School Recreational Center (ID # 245100054) monitoring station was 

established in 2006 and thus did not have enough data to calculate an average 2005 ozone design 

value and for that reason was not included in this modeling analysis. 

Based on the attainment demonstration modeling (see Chapter 13), the weight of evidence data 

analysis, and the supplemental modeling that was completed, MDE is confident that the Baltimore 

NAA will attain the 8-hour ozone NAAQS standard by June 15, 2013. 

Baltimore Serious Area 8-Hour Ozone SIP Page 133