IDEM INDIANA DEPARTMENT OF ENVIRONMENTAL MANAGEMENT

We Prolecl Hoosiers and Our Environmenl.

Mitchell E. Daniels Jr. 100 North Senate Avenue

Governor Indianapolis, Indiana 46204

(317) 232-8603

Thomas W Easterly Toll Free (800) 451-6027

Commissioner www.idem.IN.gov

May 26,2011

Ms. Susan Hedman

Regional Administrator

U.S. Environmental Protection Agency

Region 5

77 West Jackson Boulevard

Chicago, IL 60604-3950

Dear Ms. Hedman:

Re: Request for Redesignation Petition and

Maintenance Plan for the Indiana Portion

(Lake and Porter Counties) of the ChicagoGary-Lake IL-IN Nonattainment Area for

Fine Particles

The Indiana Department of Environmental Management (IDEM) submits a

Redesignation Petition and Maintenance Plan for the Indiana Portion (Lake and Porter

counties) of the Chicago-Lake IL-IN Nonattainment Area, which was designated as

nonattainment of the annual standard for fine particles on April 5, 2005. IDEM conducted

a public hearing concerning the Redesignation Petition and Maintenance Plan on May

18, 2011, and the public comment period concluded on May 20, 2011.

This submittal documents the public review process, including a detailed summary

of and response to substantive comments.

The attached document consists of the following:

Redesignation Petition and Maintenance Plan

• A formal request that the Indiana Portion (Lake and Porter counties) of the

Chicago-Lake IL-IN Nonatlainment Area be redesignated to attainment and

reclassified as maintenance. It contains and meets the requirements set forth in

Section 107 of the Clean Air Act and in United States Environmental Protection

Agency (U.S. EPA) Redesignation Guidance.

• A maintenance year of 2025 is established and 2015 and 2020 are analyzed as

interim years.

• The appendices of the document contain historical air quality trend data, projected

emission inventory data, and thorough documentation of the mobile emissions

analysis.

Recycled Paper (i) An Equal Opportunity Employer Please Recycle V
Ms. Hedman

Page 2

Motor Vehicle Emissions Budgets

• Contained in the Redesignation Petition is a new Motor Vehicle Emissions Budget

for 2016 and 2025. The Northwestern Indiana Regional Planning Commission's

(NIRPC's) travel demand forecasting model and U.S. EPA's software program

referred to as MOBILE6.2 were used to determine emissions for the annual fine

particle nonattainment area.

• A conservative margin of safety was applied to the 2016 and 2025 projected

emissions.

• The travel demand model was updated with the best available assumptions.

• Vehicle registration data gathered from the Indiana Bureau of Motor Vehicles were

used to replace the MOBILE6.2 default vehicle age distribution.

IDEM requests that U.S. EPA proceed with review and approval of this submittal.

If you have any questions or need additional information, please contact Scott Deloney,

Chief, Air Programs Branch, at (317) 233-5694.

Sincerely,

Keith Baugues

Assistant Commissioner

Office of Air Quality

KBlsadlghf

Enclosure:

Request for Redesignation Petition and Maintenance Plan Under the Annual

National Ambient Air Quality Standard for Fine Particles for the Indiana Portion of

the Chicago-Gary-Lake County, IL-IN Nonattainment Area

Cc: John Summerhays, U.S. EPA Region 5 (wi enclosures)

Matt Rau, U.S. EPA Region 5 (wi enclosures)

John Mooney, U.S. EPA Region 5 (no enclosures)

Cheryl Newton, U.S. EPA Region 5 (no enclosures)

Pat Morris, U.S. EPA Region 5 (no enclosures)

Bill Brown, NIRPC (wi enclosures)

Rob Kaleel, Illinois EPA (wi enclosures)

Scott Deloney, IDEM (no enclosures)

Christine Pedersen, IDEM (no enclosures)

Gale Ferris, IDEM (wi enclosures)
i 

REQUEST FOR REDESIGNATION AND 

MAINTENANCE PLAN 

UNDER THE ANNUAL NATIONAL 

AMBIENT AIR QUALITY 

STANDARD FOR FINE PARTICLES 

For the Indiana Portion 

of the 

Chicago-Gary-Lake County, IL-IN 

Nonattainment Area for Fine Particles 

 

Lake and Porter Counties, Indiana

Prepared By: 

The Indiana Department of Environmental Management 

 May 2011 
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iii 

TABLE OF CONTENTS 

1.0 INTRODUCTION....................................................................................................................1

1.1 Background ................................................................................................................................1 

1.2 Geographical Description ..........................................................................................................3 

1.3 Status of Air Quality ..................................................................................................................3 

2.0 REQUIREMENTS FOR REDESIGNATION ......................................................................3

2.1 General .......................................................................................................................................3 

2.2 Fine Particles Monitoring ..........................................................................................................3 

2.3 Emission Inventory ....................................................................................................................4 

2.4 Modeling Demonstration ...........................................................................................................4 

2.5 Controls and Regulations ...........................................................................................................4 

2.6 Corrective Actions for Potential Future Violations of the Fine Particle Standard ....................5 

3.0 FINE PARTICLES MONITORING .....................................................................................5

3.1 Fine Particle Monitoring Network .............................................................................................5 

3.2 Ambient Fine Particles Monitoring Data ...................................................................................6

3.3 Quality Assurance ....................................................................................................................14 

3.4 Continued Monitoring ..............................................................................................................14 

4.0 EMISSION INVENTORY ....................................................................................................14

4.1 Emission Trends .......................................................................................................................14 

4.2 Base Year Inventory ................................................................................................................25 

4.3 Emission Projections ................................................................................................................26 

4.4 Demonstration of Maintenance ................................................................................................32 

4.5 Permanent and Enforceable Emission Reductions ..................................................................33 

4.6 Provisions for Future Updates .................................................................................................33 

5.0 TRANSPORTATION CONFORMITY BUDGETS ..........................................................33

5.1 On-Road Emission Estimates ..................................................................................................33 

5.2 Overview ..................................................................................................................................33 

5.3 Analysis Years .........................................................................................................................34 

5.4 Emission Estimates ..................................................................................................................34 

5.5 Motor Vehicle Emission Budget ..............................................................................................35 

5.6 Commitment to Amend Motor Vehicle Emission Budgets Using Motor Vehicle Emission 

 Simulator (MOVES) ................................................................................................................35 

 
iv 

6.0 CONTROL MEASURES AND REGULATIONS ............................................................36

6.1 Reasonably Available Control Technology (RACT) .............................................................36 

6.2 Implementation of Past State Implementation Plan (SIP) Revisions .....................................36 

6.3 Nitrogen Oxides (NOx) Rule ..................................................................................................36 

6.4 Measures Beyond Clean Air Act SIP Requirements ..............................................................37 

6.5 Controls to Remain in Effect ..................................................................................................41 

6.6 New Source Review Provisions .............................................................................................41 

7.0 MODELING AND METEOROLOGY ..............................................................................42

7.1 Summary of Modeling Results to Support Rulemakings .......................................................42 

7.2 Lake Michigan Air Directors Consortium (LADCO) Round 5 Speciated Modeled 

 Attainment Test Results .........................................................................................................46 

7.3 LADCO Round 5 Particle Source Apportionment Results ....................................................47 

7.4 Summary of Existing Modeling Results ................................................................................56 

7.5 Meteorological Analysis for Lake and Porter Counties, Indiana ...........................................56 

7.6 Surface Air Conditions Present During High Fine Particle Concentration Days ...................56 

7.7 Upper Air Conditions Present During High Fine Particle Concentration Days .....................56 

7.8 Analyses of Atmospheric Conditions During High Fine Particle Concentration Days .........57 

7.9 Summary of Air Quality Index Days in Lake and Porter Counties, Indiana ..........................57 

7.10 Summary of Meteorological Analysis for Lake and Porter Counties, Indiana ......................59 

8.0 CORRECTIVE ACTIONS ..................................................................................................59

8.1 Commitment to Revise Plan ...................................................................................................59 

8.2 Commitment for Contingency Measures ...............................................................................60 

8.3 Contingency Measures ...........................................................................................................60 

9.0 PUBLIC PARTICIPATION ..............................................................................................61

10.0 CONCLUSIONS ..................................................................................................................62

FIGURES

Figure 3.1 Chicago Nonattainment Area .........................................................................................6 

TABLES

Table 1.1 National Ambient Air Quality Standards for Fine Particles (PM2.5) ...............................2 

Table 3.1 Monitoring Data for Indiana’s Portion of the Chicago Area ...........................................7 

Table 3.2 Monitoring Data for Illinois’ Portion of the Chicago Area .............................................8 

Table 4.1 Comparison of 2008 Estimated and 2025 Projected Emission Estimates, Lake and 

 Porter Counties, Indiana ................................................................................................32 

Table 4.2 Comparison of 2008 Estimated and 2025 Projected Emission Estimates, Entire 

 Chicago Area .................................................................................................................32 
v 

Table 5.1 Emission Estimates for On-Road Mobile Sources .....................................................34 

Table 5.2 Motor Vehicle Emission Budgets for Lake and Porter Counties ...............................35 

Table 6.1 Trends in Electric Generating Unit (EGU) NOx Emissions Statewide in Indiana .....37 

Table 7.1 Clean Air Transport Rule Modeling Results from U.S. EPA - 2010 .........................43 

Table 7.2 LADCO Round 6 Modeling Results for Annual PM2.5 – Without the Clean Air 

 Interstate Rule Emission Reductions ..........................................................................45 

Table 7.3 LADCO Round 5 Speciated Modeled Attainment Test Modeling Results for 

 Lake and Porter Counties, Indiana .............................................................................47 

Table 7.4 Ranking and Percentage of Highest Number of Days at Air Quality Index 

 Levels of Health Concern ...........................................................................................59 

GRAPHS

Graph 3.1 Fine Particle Design Values for Indiana’s Portion of the Chicago Area, 

 2006 through 2010 ......................................................................................................10 

Graph 3.2 Fine Particle Design Values for Illinois’ Portion of the Chicago Area, 

 2006 through 2010 ......................................................................................................11 

Graph 3.3 Annual Fine Particle Trends for Indiana’s Portion of the Chicago Area, 

 2006 through 2010 ......................................................................................................12 

Graph 3.4 Annual Fine Particle Trends for Illinois’ Portion of the Chicago Area, 

 2006 through 2010 ......................................................................................................13 

Graph 4.1 NOx Point Source Emission Trends, Lake and Porter Counties, Indiana, 

 2002, 2005, and 2008 .................................................................................................15 

Graph 4.2 Sulfur Dioxide (SO2) Point Source Emission Trends, Lake and Porter Counties, 

Indiana, 2002, 2005, and 2008 ...................................................................................16 

Graph 4.3 Direct PM2.5 Point Source Emission Trends, Lake and Porter Counties, Indiana, 

 2002, 2005, and 2008 .................................................................................................16 

Graph 4.4 NOx Point Source Emission Trends, Entire Chicago Area, 2002, 2005, and 2008 ....17 

Graph 4.5 SO2 Point Source Emission Trends, Entire Chicago Area, 2002, 2005, and 2008 ....17 

Graph 4.6 Direct PM2.5 Point Source Emission Trends, Entire Chicago Area, 

 2002, 2005, and 2008 .................................................................................................18 

Graph 4.7 NOx Emission Trends, Lake and Porter Counties, Indiana, 2002, 2005, and 2008 ...19 

Graph 4.8 SO2 Emission Trends, Lake and Porter Counties, Indiana, 2002, 2005, and 2008 ....20 

Graph 4.9 Direct PM2.5 Emission Trends, Lake and Porter Counties, Indiana, 

 2002, 2005, and 2008 .................................................................................................20 

Graph 4.10 NOx Emission Trends, Entire Chicago Area, 2002, 2005, and 2008 .........................21 

Graph 4.11 SO2 Emission Trends, Entire Chicago Area, 2002, 2005, and 2008 ..........................21 

Graph 4.12 Direct PM2.5 Emission Trends, Entire Chicago Area, 2002, 2005, and 2008 .............22 

Graph 4.13 NOx Emissions from EGUs, Lake and Porter Counties, Indiana, 1999 to 2009 ........23 

Graph 4.14 Indiana Statewide NOx Emissions from EGUs, 1999 to 2009 ...................................24 

Graph 4.15 SO2 Emissions from EGUs, Lake and Porter Counties, Indiana, 1999 to 2009 .........24 

Graph 4.16 Indiana Statewide SO2 Emissions from EGUs, 1999 to 2009 ....................................25 

Graph 4.17 Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected 

 NOx Emissions, Lake and Porter Counties, Indiana ...................................................27 

Graph 4.18 Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected 

 SO2 Emissions, Lake and Porter Counties, Indiana ...................................................28 
vi 

Graph 4.19 Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected 

 Direct PM2.5 Emissions, Lake and Porter Counties, Indiana ......................................28 

Graph 4.20 Comparison of 2005 and 2008 Estimated and 2020, 2015, and 2025 Projected 

NOx, SO2, and Direct PM2.5 Emissions, Lake and Porter Counties, Indiana ..............29 

Graph 4.21 Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected 

 NOx Emissions, Entire Chicago Area .........................................................................29 

Graph 4.22 Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected` 

 SO2 Emissions, Entire Chicago Area ..........................................................................30 

Graph 4.23 Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected 

 Direct PM2.5 Emissions, Entire Chicago Area ............................................................30 

Graph 4.24 Comparison of 2005 and 2008 Estimated and 2015 and 2025 Projected NOx, 

 SO2, and Direct PM2.5 Emissions, Entire Chicago Area ............................................31 

Graph 7.1 PM2.5 Design Value Trends for Lake and Porter Counties, Indiana, 2000 to 2010 ...44 

Graph 7.2 LADCO Round 6 Modeling Results for Lake and Porter Counties, Indiana for 

 2012 and 2018 ............................................................................................................46 

CHARTS

Chart 7.1 Regional/Emission Sector Particulate Source Apportionment Technology 

 (PSAT) Results ...........................................................................................................48 

Chart 7.2 Modeled Contributions by Specie at the East Chicago – Franklin School PM2.5 

 Monitor .......................................................................................................................52 

Chart 7.3 Modeled Contributions by Specie at the Griffith PM2.5 Monitor ...............................52 

Chart 7.4 Modeled Contributions by Specie at the Gary – Madison Street PM2.5 Monitor .......53 

Chart 7.5 Modeled Contributions by Specie at the Gary – Ivanhoe School PM2.5 Monitor ......53 

Chart 7.6 Modeled Contributions by Specie at the Hammond – Purdue PM2.5 Monitor ...........54 

Chart 7.7 Modeled Contributions by Specie at the Hammond – Clark High School 

 PM2.5 Monitor .............................................................................................................54 

Chart 7.8 Modeled Contributions by Specie at the Dunes National Lakeshore PM2.5 Monitor 55 

Chart 7.9 Modeled Contributions by Specie at the Ogden Dunes PM2.5 Monitor .....................55 

Chart 7.10 Distribution of PM2.5 Concentration Days on the AQI Levels of Health Concern, 

 Lake and Porter Counties, Indiana .............................................................................58 

 
vii 

APPENDICES

A Air Quality System (AQS) and Indiana Department of Environmental Management 

 (IDEM) Fine Particle Monitor Data Values for the Chicago Area (2000 –2010) 

B NOx, SO2, and Direct PM2.5 Point Source Emissions (2002, 2005, and 2008), Chicago Area 

C NOx, SO2, and Direct PM2.5 Emission Trends, All Sources (2002, 2005, and 2008), 

Chicago Area 

D NOx and SO2 Emission Trends from EGUs, Lake and Porter Counties, Indiana (1999 to 

2009) 

E 2005 and 2008 Base Year Emission Inventories and 2015, 2020, and 2025 Projected 

Emission Inventories for NOx, SO2, and Direct PM2.5, Chicago Area 

F Example Mobile Source Input and Output Calculation Files for Lake and Porter Counties, 

Indiana 

G IDEM - Area Source Inventory Standard Operating Procedure 

H LADCO Emission Estimates Technical Support Document 

I LADCO Round 5 Modeling Technical Support Document (Round 5 Photochemical 

Modeling Based on “Base M” Emission Inventory, revised version of “Base K”) 

J Modeling Summary 

K Public Participation Process Documents 

 
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1

REQUEST FOR REDESIGNATION AND MAINTENANCE PLAN 

UNDER THE ANNUAL NATIONAL AMBIENT AIR 

QUALITY STANDARD FOR FINE PARTICLES 

CHICAGO-GARY-LAKE COUNTY IL-IN AREA 

1.0 INTRODUCTION

 

This document supports Indiana’s request that Lake and Porter counties, Indiana, which are part 

of the Chicago-Gary-Lake County IL-IN nonattainment area for fine particles (herein referred to 

as the “Chicago Area”), be redesignated from nonattainment to attainment of the 1997 annual 

standard for fine particles. All monitors for fine particles in the Chicago Area have recorded 

three years of quality assured ambient air quality monitoring data for the years 2008 through 

2010, demonstrating attainment with the annual standard for fine particles, therefore; Indiana’s 

portion of the Chicago Area is eligible for redesignation. 

Section 107 of the Clean Air Act (CAA) establishes specific requirements to be met in order for 

an area to be considered for redesignation, including: 

(a) A determination that the area has attained the annual standard for fine particles. 

(b) A State Implementation Plan (SIP) for the area under Section 110(k) is fully 

approved. 

(c) A determination that the improvement in air quality is due to permanent and 

enforceable reductions in emissions resulting from implementation of the SIP and 

other federal requirements.

(d) A maintenance plan under Section 175A is fully approved. 

(e) A determination that all Section 110 and Part D requirements have been met. 

A maintenance plan provides for the continued attainment of the air quality standard by an area 

for a period of ten years after the United States Environmental Protection Agency (U.S. EPA) 

has formally redesignated the area to attainment. The plan also provides assurances that even if 

there is a subsequent exceedance of the air quality standard, then measures in the maintenance 

plan will prevent any future occurrences through contingency measures that would be triggered. 

This document addresses each of these requirements, and provides additional information to 

support continued compliance with the annual standard for fine particles. 

1.1 Background

The CAA requires states with areas designated nonattainment of the applicable National 

Ambient Air Quality Standard (NAAQS) for fine particles to develop SIPs to expeditiously 

attain and maintain the standard. In 1997, U.S. EPA set daily and annual air quality standards 

for fine particles (PM2.5), as shown in Table 1.1. The terms “fine particles” and “PM2.5” are used 

synonymously throughout this document. The PM2.5 standards were legally challenged and 

upheld by the U.S. Supreme Court in February of 2001. In 1999, the Indiana Department of 
2

Environmental Management (IDEM) began monitoring for fine particle concentrations. U.S. 

EPA designated areas in Indiana under the annual fine particles standard on December 17, 2004, 

as attainment, nonattainment or unclassifiable, with an effective date of April 5, 2005. 

Table 1.1 

National Ambient Air Quality Standards for Fine Particles 

 

Annual 24-Hour 

1997 PM2.5 Standards 

15 μg/m3

Annual arithmetic mean, 

averaged over three years 

65 μg/m3

24-hour average, 98th percentile, 

averaged over three years 

2006 PM2.5 Standards 

15 μg/m3

Annual arithmetic mean, 

averaged over three years 

35 μg/m3

24-hour average, 98th percentile, 

averaged over three years 

Note: The Chicago Area meets the 1997 and 2006 24-hour NAAQS for fine particles. Since this area is 

solely designated nonattainment under the 1997 annual standard for fine particles, this document only 

addresses the annual standard. 

On December 17, 2004, based on 2001 through 2003 monitoring data, U.S. EPA designated the 

Chicago Area as nonattainment of the annual standard for fine particles (40 CFR 81.315). The 

Chicago Area was subject to Section 172 of the CAA, including the development of a plan to 

reduce nitrogen oxides (NOx), sulfur dioxide (SO2), and direct fine particle (PM2.5) emissions 

and a demonstration that the area will meet the annual standard for fine particles by April 5, 

2010. In order to satisfy these requirements, Indiana submitted a redesignation petition and 

maintenance plan to U.S. EPA on April 3, 2008, demonstrating that Lake and Porter counties, 

Indiana met the NAAQS for fine particles by April 5, 2010, with an ample margin of safety. 

The Chicago Area monitors have continued to meet the annual NAAQS for fine particles since 

the end of 2007. 

There were no fine particle monitors in the Chicago Area that violated the 1997 24-hour standard 

for fine particles and none that currently violate the 2006 24-hour standard for fine particles. As 

a result, the Chicago Area was designated nonattainment for fine particles solely under the 1997 

annual standard. Therefore, this document pertains only to the 1997 annual standard for fine 

particles. 

The Chicago nonattainment area for fine particles, as defined in Section 1.2, has not previously 

been subject to nonattainment area rulemakings for fine particles. However, the Chicago Area 

had been subject to nonattainment area rulemakings under the 1-hour ozone standard. The 1-

hour ozone standard was revoked on June 15, 2005. Lake and Porter counties had also been 

subject to nonattainment rulemakings under the 8-hour ozone standard and were redesignated to 

attainment and classified as maintenance under the 8-hour ozone standard on May 11, 2010. 

The Illinois portion of the Chicago Area 8-hour ozone nonattainment area remains designated as 

“nonattainment” under the 8-hour ozone standard. 
3

1.2 Geographical Description

The Chicago nonattainment area for fine particles consists of Lake and Porter counties, Indiana 

and Cook, DuPage, Kane, Lake, McHenry, and Will counties, and portions of Grundy (Aux 

Sable and Goose Lake Townships) and Kendall (Oswego Township) counties, Illinois. The 

Chicago Area contains such cities as Gary, Hammond, East Chicago, Portage, and Valparaiso in 

Indiana and Chicago, Elgin, Aurora, and Joliet in Illinois. This area is depicted in Figure 3.1. 

IDEM and Illinois Environmental Protection Agency (IEPA) are responsible for assuring the 

nonattainment area for fine particles complies with the CAA requirements. IDEM is responsible 

for Lake and Porter counties, Indiana, while IEPA is responsible for Cook, DuPage, Kane, Lake, 

McHenry, and Will Counties, and portions of Grundy (Aux Sable and Goose Lake Townships) 

and Kendall (Oswego Township) counties, Illinois. IDEM and IEPA have worked cooperatively 

with U.S. EPA Region V to address attainment planning issues. 

Although the agencies have worked together on a comprehensive plan for the multi-state 

nonattainment areas, the State of Illinois is required to make a separate submittal for its portion 

of the planning components to U.S. EPA. As such, this submittal only covers Lake and Porter 

counties, Indiana. 

1.3 Status of Air Quality

Monitoring data for fine particles for the three years, 2008 through 2010, demonstrates that air 

quality has met the annual NAAQS for fine particles in the Chicago Area. This fact, 

accompanied by the permanent and enforceable reductions in emission levels discussed in 

Section 4.0, justifies a redesignation to attainment for the area based on Section 107(d)(3)(E) of 

the CAA. 

2.0 REQUIREMENTS FOR REDESIGNATION

2.1 General

Section 110 and Part D of the CAA list a number of requirements that must be met by 

nonattainment areas prior to consideration for redesignation to attainment. In addition, U.S. EPA 

has published detailed guidance in a document entitled “Procedures for Processing Requests to 

Redesignate Areas to Attainment”, issued September 4, 1992, to Regional Air Directors. This 

document is hereafter referred to as “Redesignation Guidance”. This Request for Redesignation 

and Maintenance Plan is based on the Redesignation Guidance, supplemented with additional 

guidance received from staff of the Attainment Planning and Maintenance Section of U.S. EPA 

Region V. The specific requirements for redesignation are listed below. 

2.2 Fine Particles Monitoring 

1) A demonstration that the annual standard for fine particles, as published in 40 

Code of Federal Regulations (CFR) 50.13, has been attained. Fine particle 
4

monitoring data must show that violations of the annual ambient standard are no 

longer occurring. 

2) Ambient monitoring data quality assured in accordance with 40 CFR 58.15, 

recorded in the U.S. EPA Air Quality System (AQS) database, and available for 

public view. 

3) A showing that the three-year average of annual values, based on data from all 

monitoring sites in the area or its affected downwind environs, do not exceed 15.0 

micrograms per cubic meter (μg/m3

). This showing must rely on three complete, 

consecutive calendar years of quality assured data. 

4) A commitment that, once redesignated, the state will continue to operate an 

appropriate monitoring network to verify the area is in compliance (maintenance) 

with the standard. 

2.3 Emission Inventory 

1) A comprehensive emission inventory of the precursors of fine particles (direct 

PM2.5, NOx, and SO2 completed for the base year (2008 in this case). 

2) A projection of the emission inventory to a year at least ten years following 

redesignation. 

3) A demonstration that the projected level of emissions is sufficient to maintain the 

annual standard for fine particles. 

4) A demonstration that improvement in air quality between the year violations 

occurred and the year attainment was achieved is based on permanent and 

enforceable emission reductions and not on temporary adverse economic 

conditions or unusually favorable meteorology. 

5) Provisions for future updates of the inventory to enable tracking of the emission 

levels, including emission inventory statements from emission sources. 

2.4 Modeling Demonstration 

While no modeling is required for redesignating nonattainment areas, IDEM has evaluated the 

results of federal control-case modeling to demonstrate that compliance with the standard will be 

maintained. 

2.5 Controls and Regulations 

1) A U.S. EPA approved SIP control strategy that includes Reasonably Available 

Control Technology (RACT) requirements for existing stationary sources covered 
5

by Control Technology Guidelines (CTG) and non-CTG RACT for all major 

sources. 

2) Evidence that control measures required in past SIP revisions have been fully 

implemented. 

 

3) Acceptable provisions to provide for new source review. 

4) Assurances that existing controls will remain in effect after redesignation, unless 

the state demonstrates through photochemical modeling that the standard can be 

maintained without one or more controls. 

5) If appropriate, a commitment to adopt a requirement that all transportation plans 

conform with, and are consistent with, the SIP. 

2.6 Corrective Actions for Potential Future Violations of the Fine Particle Standard

1) A commitment to submit a revised plan eight years after redesignation. 

2) A commitment to expeditiously enact and implement additional contingency 

control measures in response to exceeding specified predetermined levels 

(triggers) or in the event that future violations of the ambient standard occur. 

3) A list of potential contingency measures that would be implemented in such an 

event. 

4) A list of NOx, SO2, and direct PM2.5 sources potentially subject to future controls. 

3.0 FINE PARTICLES MONITORING

3.1 Fine Particle Monitoring Network

There are currently twenty-three Federal Reference Method monitors measuring fine particle 

concentrations in this nonattainment area. Six monitors are located in Indiana’s portion of the 

nonattainment area and are operated by IDEM’s Office of Air Quality (OAQ). Seventeen 

monitors are located in Illinois’s portion of the nonattainment and are operated by IEPA’s 

Bureau of Air; Air Monitoring Section (AMS). A listing of the monitor readings from 2008 

through 2010 are shown in Tables 3.1, 3.2, and Appendix A and was retrieved from U.S. EPA’s 

AQS database. The locations of the monitoring sites for this nonattainment area are shown in 

Figure 3.1. 

There are also four source oriented monitors located in the nonattainment area that collect 

background fine particle concentrations. Two monitors are located in Lake County, Indiana and 

are operated by IDEM’s OAQ (Gary – IITRI (18-089-0022) and Gary – Burr Street (18-089-

0026)). Two monitors are located in Cook County, Illinois and are operated by IEPA’s Bureau 
6

of Air AMS (McCook (17-031-1016) and Schiller Park (17-031-3103)). While the source 

oriented monitors are not used to determine attainment with the annual standard for fine 

particles, the monitoring locations and data are included as supporting material. 

Three monitors in Indiana’s portion of the nonattainment area have been discontinued. The Gary 

- Federal Building monitor (18-089-1016) in Lake, County, Indiana was discontinued in 

September 2002. The Dunes National Lakeshore monitor (18-127-0020) in Porter County, 

Indiana, and the Gary - Ivanhoe School monitor (18-089-1003) in Lake County, Indiana were 

discontinued on December 31, 2007. 

Figure 3.1 

Chicago Nonattainment Area 

3.2 Ambient Fine Particles Monitoring Data

The following information summarizes U.S. EPA's "Guideline on Data Handling Conventions 

for the PM NAAQS," U.S. EPA-454/R-99-008, April 1999. Three complete years of fine 

particle monitoring data are required to demonstrate attainment at a monitoring site. The annual 

ambient air quality standard for fine particles is met at an ambient air quality monitoring site 
7

when the three-year average of the annual average of fine particle concentrations is less than or 

equal to 15.0 μg/m3

. When this occurs, the site is said to be in attainment. While calculating 

design values, three significant digits must be carried in the computations, with final values 

rounded to the nearest 0.1 μg/m3

. Decimals 0.05 or greater are rounded up, and those less than 

0.05 are rounded down, so that 15.049 μg/m3

 is the largest concentration that is less than or equal 

to 15.0 μg/m3. Values at or below 15.0 μg/m3meet the standard. Values equal to or greater than 

15.1 μg/m3

 exceed the standard. 

Data handling procedures are applied on an individual basis at each monitor in the area. An 

individual site’s three-year average of the annual average fine particles concentration is also 

called the site’s design value. An area is in compliance with the annual NAAQS for fine 

particles only if all monitoring sites meet the NAAQS. The air quality design value for the area 

is the highest design value among all sites in the area. Table 3.1 outlines the annual fine particle 

values by site and the 2008 through 2010 design values for the six active fine particle monitoring 

sites in Indiana’s portion of the Chicago Area. Table 3.2 outlines the annual fine particle values 

by site and the 2008 through 2010 design values for the seventeen fine particle monitoring sites 

in Illinois’ portion of the Chicago Area. Appendix A contains the complete monitoring data 

monitoring summary from 2000 to 2010 for all of the Chicago Area monitors which includes the 

twenty-three active, the four source oriented, and the three discontinued fine particles monitoring 

sites. 

Table 3.1 

Monitoring Data for Indiana’s Portion of the Chicago Area 

(Annual Average and 2008 - 2010 Design Values)

SITE ID COUNTY SITE NAME YEAR

Annual 

Average 

(μg/m3) 

2008-2010 

Design Value 

(μg/m3) 

18-089-0006 Lake East Chicago – 

Franklin School 

2008 11.95 

2009 11.34 11.9

2010 12.48 

18-089-0027 Lake Griffith 2008 11.69 

2009 11.00 11.7

2010 12.39 

18-089-2004 Lake Hammond – Purdue 2008 11.66 

2009 N/A* N/A*

2010 12.30 

18-089-2010 Lake Hammond – Clark 

High School 

2008 12.42 

2009 10.80 11.7

2010 11.90 

18-089-0031 Lake Gary – Madison Street 2008 12.27 

2009 12.12 12.4 

2010 12.90 

 
8

18-127-0024 Porter Ogden Dunes 2008 10.89 

2009 11.29 11.2

2008 11.56 

*The Hammond – Purdue monitoring site was physically removed to accommodate heating and cooling building 

repairs on the roof which were conducted from February 12, 2009 through November 18, 2009. As a result, the 

2009 monitoring data and 2008 through 2010 three year design value are considered incomplete.

Table 3.2 

Monitoring Data for Illinois’ Portion of the Chicago Area 

(Annual Average and 2008 through 2010 Design Values) 

SITE ID COUNTY SITE NAME YEAR

Annual 

Average 

(μg/m3) 

2008-2010 

Design 

Value 

(μg/m3) 

17-031-0022 Cook Chicago – Washington 

High School 

2008 12.54 

2009 11.62 12.7

2010 14.04 

17-031-0050 Cook Chicago – Southeast 

Police Station 

2008 11.80 

2009 10.99 11.8

2010 12.47 

17-031-0052 Cook Chicago – Mayfair 

Pump Station 

2008 12.18 

2009 12.69 12.5

2010 12.57 

17-031-0057 Cook Chicago – Springfield 

Pump Station 

2008 12.03 

2009 11.33 11.8

2010 12.03* 

17-031-0076 Cook Chicago – Com Ed 

Maintenance Building 

2008 11.89 

2009 11.12 11.8

2010 12.25 

17-031-2001 Cook Blue Island 2008 12.50 

2009 11.68 11.9

2010 11.59 

17-031-3301 Cook Summit 2008 12.03 

2009 11.62 12.0

2010 12.23 

17-031-4007 Cook Des Plaines 2008 11.35 

2009 11.02 11.0

2010 10.60 

17-031-4201 Cook Northbrook 2008 10.09 

2009 9.33 9.6

2010 9.34 

17-031-6005 Cook Cicero 2008 13.25* 

2009 11.98* 12.4

2010 11.90 
9

17-043-4002 DuPage Naperville 2008 11.28 

2009 9.83 10.9

2010 11.67 

17-089-0003 Kane Elgin 2008 10.79 

2009 9.61 10.6

2010 11.29 

17-089-0007 Kane Aurora 2008 10.34 

2009 10.01 10.6

2010 11.44 

17-097-1007 Lake Zion 2008 9.34 

2009 8.83 9.3 

2010 9.66 

17-111-0001 McHenry Cary 2008 10.10 

2009 9.65 10.0

2010 10.24 

17-197-1002 Will Joliet 2008 11.66 

2009 10.52 11.3

2010 11.83 

17-197-1011 Will Braidwood 2008 10.31 

2009 8.73 9.7

2010 10.02 

*Indicates the mean does not satisfy summary criteria. 

Red Text Indicates Incomplete Data 

Graph 3.1 visually demonstrates the 2006 through 2010 design values for Indiana’s portion of the 

Chicago Area. 

 
10

Graph 3.1

Fine Particle Design Values for Indiana’s Portion of the Chicago Area, 

2006 through 2010 

Red line represents the annual standard for fine particles of 15 μg/m3

The Hammond - Purdue monitoring site was physically removed to accommodate heating and cooling building 

repairs on the roof which were conducted from February 12, 2009 through November 18, 2009. As a result, the 

2007 through 2009 and 2008 through 2010 three year design values are considered incomplete and are not included 

in Graph 3.1. 

Graph 3.2 visually demonstrates the 2006 through 2010 design values for Illinois’ portion of the 

Chicago Area. 

 

8.0

9.0

10.0

11.0

12.0

13.0

14.0

15.0

16.0

06‐08 07‐09 08‐10

East Chicago ‐ Franklin School Griffith

Hammond ‐ Purdue Hammond ‐ Clark High School

Gary ‐ Madison Street Ogden Dunes

ug/m3
11

Graph 3.2 

Fine Particle Design Values for Illinois’ Portion of the Chicago Area, 

 2006 through 2010 

Red line represents the annual standard for fine particles of 15 μg/m3.

 

8.0

9.0

10.0

11.0

12.0

13.0

14.0

15.0

16.0

06‐08 07‐09 08‐10

Chicago ‐WashingtonHighSchool Chicago ‐SoutheastPoliceStation Chicago ‐MayfairPumpStation

Chicago ‐SpringfieldPumpStation Chicago ‐ComEdMaintenanceBuilding BlueIsland

Summit DesPlaines Northbrook

Cicero Naperville Elgin

Aurora Zion Cary

Joliet Braidwood

ug/m3
12

Graph 3.3 

Annual Fine Particle Trends for Indiana’s Portion of the Chicago Area, 

2006 through 2010 

Red line represents the annual standard for fine particles of 15 μg/m3

The Hammond - Purdue monitoring site was physically removed to accommodate heating and cooling building 

repairs on the roof which were conducted from February 12, 2009 through November 18, 2009. As a result, the 

2009 monitoring data is considered incomplete and has not been included in Graph 3.3.

 

8.0

9.0

10.0

11.0

12.0

13.0

14.0

15.0

16.0

2006 2007 2008 2009 2010

East Chicago ‐ Franklin School Griffith

Gary ‐ Ivanhoe School Hammond ‐ Purdue

Hammond ‐ Clark High School Gary ‐ Madison Street

Dunes National Lakeshore Ogden Dunes

ug/m3

Year
13

Graph 3.4 

Annual Fine Particle Trends for Illinois’ Portion of the Chicago Area, 

2006 through 2010 

Red line represents the annual standard for fine particles of 15 μg/m3

The design values for Lake and Porter counties, Indiana, along with the nonattainment area in its 

entirety, demonstrate that the annual NAAQS for fine particles has been attained. Appendix A 

contains the complete fine particles monitoring data summary for the years 2000 through 2010. 

Graphs 3.1 and 3.2 show the trends in design values, while Graphs 3.3 and 3.4 show the trend for 

annual fine particles. A comprehensive list of the design values for the Chicago Area fine 

particles monitoring sites over the 2000 through 2010 monitoring period is outlined in Appendix 

A. The area's design values have recently trended downward, as emissions have declined due to 

programs such as the Acid Rain program and cleaner automobiles and fuels both regionally and 

locally. U.S. EPA’s rule to control nitrogen oxides from specific source categories (40 CFR 

Parts 51, 72, 75, and 96, published on October 17, 1998 and referred to as the “NOx SIP Call”) 

has significantly reduced emissions from large electric generating units (EGUs), industrial 

boilers, and cement kilns. Indiana's NOx SIP Call Rule was adopted into the Indiana 

Administrative Code (IAC) on June 6, 2001 at 326 IAC 10-3 and 326 ICA 10-4. The elevated 

8.0

9.0

10.0

11.0

12.0

13.0

14.0

15.0

16.0

17.0

18.0

2006 2007 2008 2009 2010

Chicago ‐WashingtonHighSchool Chicago ‐SoutheastPoliceStation

Chicago ‐MayfairPumpStation Chicago ‐SpringfieldPumpStation

Chicago ‐ComEdMaintenanceBuilding BlueIsland

Summit DesPlaines

Northbrook Cicero

Naperville Elgin

Aurora Zion

Cary Joliet

Braidwood

ug/m3

Year
14

fine particle values for 2005 are considered an abnormal occurrence. An analysis of 

meteorological conditions and monitoring values is included in Section 7.0 and supports the 

conclusion that attainment of the standard as of 2010 is not the result of unusually favorable 

meteorological conditions. It is expected that this downward trend will persist as the above 

programs continue and U.S. EPA’s proposed Clean Air Transport Rule is implemented. 

3.3 Quality Assurance

Indiana and Illinois have quality assured all data shown in Appendix A in accordance with 40 

CFR 58.10 and recorded the data in the AQS database and, thus, the data is available to the 

public. 

3.4 Continued Monitoring

Indiana and Illinois commit to continue monitoring fine particle concentrations at the active sites 

indicated in Tables 3.1, 3.2, and Appendix A. IDEM will consult with U.S. EPA Region V staff 

prior to making changes to the existing Indiana monitoring network through the annual network 

review should changes become necessary in the future. IDEM will continue to quality assure the 

Indiana monitoring data to meet the requirements of 40 CFR 58. IDEM will enter all data into 

AQS on a timely basis in accordance with federal guidelines. 

4.0 EMISSION INVENTORY 

U.S. EPA’s Redesignation Guidance and Implementation Rules require the submittal of a 

comprehensive inventory of precursor emissions for fine particles (NOx, SO2, and direct PM2.5) 

representative of the year when the area achieves attainment of the annual NAAQS for fine 

particles (base year). IDEM is using 2008 as the base year. IDEM must also demonstrate that 

the improvement in air quality between the year that violations occurred and the year that 

attainment was achieved is based on permanent and enforceable emission reductions. Other 

requirements related to the emission inventory include: a projection of the emission inventory to 

a year at least ten years following redesignation; a demonstration that the projected level of 

emissions is sufficient to maintain the annual standard for fine particles; and, a commitment to 

provide future updates of the inventory to enable tracking of emission levels during the ten year 

maintenance period. Consistent with the federal implementation rule for fine particles, IDEM 

and U.S. EPA do not consider volatile organic compounds (VOCs) or ammonia (NH3) to be 

significant contributors to fine particles. The following subsections address each of these 

requirements. 

4.1 Emission Trends

Point Sources

The point source data are obtained from Indiana's emissions reporting program and are based on 

county point source totals. Lake and Porter counties, Indiana, had a 34.31% reduction in NOx 

point source emissions, a 7.34% reduction in SO2 point source emissions, and a 8.71% reduction 
15

in direct PM2.5 point source emissions from 2002 to 2008. Lake and Porter counties, Indiana, 

had a 4.77% reduction in NOx point source emissions, a slight increase (14.08%) in SO2 point 

source emissions, and a slight increase (3.49%) in direct PM2.5 point source emissions from 2005 

to 2008. A moderate increase in Lake and Porter counties, Indiana, in direct PM2.5 point source 

emissions from 2005 to 2008 is noted, however, this increase in direct PM2.5 emissions is due to 

the fact that most companies did not submit their direct PM2.5 emissions data in 2005 but did 

submit direct PM2.5 data in the 2009 emission inventory, from which the 2008 inventory is 

extrapolated. Graphs 4.1, 4.2, and 4.3 demonstrate the trend in point source emissions of NOx, 

SO2, and direct PM2.5 for the Lake and Porter counties, Indiana that generally correspond to the 

years of monitored values used in this redesignation petition. 

Point source data for Illinois’ portion of the Chicago Area is based on county point source. Point 

source data for the years 2002 and 2008 were taken directly from Illinois EPA’s document 

entitled Maintenance Plan for the Chicago Nonattainment for the 1997 PM2.5 National Ambient 

Air Quality Standard, prepared September 7, 2010. This document is hereafter referred to as the 

“Chicago Maintenance Plan”. The 2005 point source data for Illinois’ portion of the Chicago 

nonattainment area were interpolated from the 2002 and 2008 emissions data. The Chicago Area 

had a 33.93% reduction in NOx point source emissions, a 19.48% reduction in SO2 point source 

emissions, and a slight increase (4.61%) in direct PM2.5 point source emissions from 2002 to 

2008. The Chicago Area had a 12.72% reduction in NOx point source emissions, a 5.62% 

reduction in SO2 point source emissions, and a slight increase (7.95%) in direct PM2.5 point 

source emissions from 2005 to 2008. The moderate increase in direct PM2.5 emissions is far 

outweighed by the significant reductions in NOx and SO2 that have occurred and will continue to 

occur in the future. Graphs 4.4, 4.5, and 4.6 demonstrate the trend in point source emissions of 

NOx, SO2, and direct PM2.5 emissions for the entire Chicago Area. Graphs and data tables of 

emissions for the point source category can be found in Appendix B. 

Graph 4.1 

NOx Point Source Emission Trends, Lake and Porter Counties, 

Indiana, 2002, 2005, and 2008 

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

2002 2005 2008

Tons per Year

Nitrogen Oxides Year
16

Graph 4.2 

 SO2 Point Source Emission Trends, Lake and Porter Counties, 

Indiana, 2002, 2005, and 2008 

Graph 4.3 

Direct PM2.5 Point Source Emission Trends, Lake and Porter Counties, 

Indiana, 2002, 2005, and 2008 

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

2002 2005 2008

Tons per Year

Sulfur Dioxide

Year

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

2002 2005 2008

Tons per Year

Direct Fine Particles Year
17

Graph 4.4 

NOx Point Source Emission Trends, Entire Chicago Area, 2002, 2005, and 2008 

Graph 4.5 

SO2 Point Source Emission Trends Entire Chicago Area, 2002, 2005, and 2008 

 

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

2002 2005 2008

Tons per Year

Nitrogen Oxides

Year

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

180,000

200,000

2002 2005 2008

Tons per Year

Sulfur Dioxide

Year
18

Graph 4.6 

Direct PM2.5 Point Source Emission Trends, Entire Chicago Area, 2002, 2005, and 2008 

All Anthropogenic Sources

Periodic inventories, which include emissions from all sectors (mobile, area, nonroad, and point 

source), were prepared for 2002, 2005, and 2008. The 2008 data for Lake and Porter counties, 

Indiana were extrapolated from the 2005 emission inventory. The 2002 and 2008 data for 

Illinois’ portion of the Chicago Area were taken directly from the Chicago Maintenance Plan. 

The 2005 data were interpolated from the 2002 and 2008 emissions data. Regional NOx

emission reductions affect fine particle levels in the Chicago Area far more so than NOx

emission reductions within the nonattainment area itself. These emission trends roughly follow 

the years of monitored trends discussed in Section 3.0. There is a downward trend in NOx

emissions from 2002 to 2005 and a further decrease through 2008. The decrease in NOx can be 

largely attributed to the impact of the NOx SIP Call. There is a general downward trend in direct 

PM2.5 and SO2 emissions from 2002 to 2008, as well. As noted previously, there is an overall 

increase in direct PM2.5 anthropogenic emissions in Lake and Porter counties, Indiana, but an 

overall decrease in the entire nonattainment area. Graphs and data tables of emissions from each 

source category are available in Appendix C. 

Mobile emission inventories and projections for Lake and Porter counties, Indiana were prepared 

by the Northwestern Indiana Regional Planning Commission (NIRPC), the Indiana Department 

of Transportation, and IDEM and are explained in further detail in Section 5.0. All 2005 data for 

Lake and Porter counties, Indiana are from the 2005 periodic inventory which has been identified 

as one of the preferred databases for SIP development. All 2008 emissions were extrapolated 

0

3,000

6,000

9,000

12,000

15,000

2002 2005 2008

Tons per Year

Direct Fine Particles Year
19

from the 2005 Lake Michigan Air Directors Consortium’s (LADCO’s) modeling inventory, 

using LADCO’s growth factors, for all sectors except point sources (electrical generating units 

and non-electrical generating units). Point source emissions for 2008 were compiled from 

Indiana’s annual emissions inventory database. 

 

Graphs 4.7, 4.8, and 4.9 show the trend in anthropogenic emissions for Lake and Porter counties, 

Indiana. Graphs 4.10, 4.11, and 4.12 show the trend in anthropogenic emissions for the entire 

Chicago Area. The emission inventory development and emissions projection discussion below, 

with the exception of the mobile emission inventory and projections, identify procedures used by 

IDEM and LADCO regarding emissions for the Chicago Area. 

Graph 4.7 

NOx Emission Trends, Lake and Porter Counties, Indiana, 2002, 2005, and 2008 

 

0

20,000

40,000

60,000

80,000

100,000

120,000

2002 2005 2008

Tons per Year

Nitrogen Oxides

Year
20

Graph 4.8 

SO2 Emission Trends, Lake and Porter Counties, Indiana, 2002, 2005, and 2008 

Graph 4.9 

Direct PM2.5 Emission Trends, Lake and Porter Counties, Indiana, 2002, 2005, and 2008 

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

2002 2005 2008

Tons per Year

Sulfur Dioxide

Year

0

3,000

6,000

9,000

12,000

15,000

2002 2005 2008

Tons per Year

Direct Fine Particles

Year
21

Graph 4.10 

NOx Emission Trends, Entire Chicago Area, 2002, 2005, and 2008 

Graph 4.11 

SO2 Emission Trends, Entire Chicago Area, 2002, 2005, and 2008 

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

400,000

450,000

500,000

2002 2005 2008

Tons per Year

Nitrogen Oxides Year

0

50,000

100,000

150,000

200,000

250,000

2002 2005 2008

Tons per Year

Sulfur Dioxide

Year
22

Graph 4.12 

Direct PM2.5 Emission Trends, Entire Chicago Area, 2002, 2005, and 2008 

EGU Sources

Both NOx and SO2 emissions are decreasing substantially in Lake and Porter counties, Indiana, 

as well as statewide in response to national programs affecting all EGUs, such as the Acid Rain 

program and the NOx SIP Call. Other sectors of the inventory also impact the formation of fine 

particles, but large regional sources, such as EGUs, have a substantial impact on the formation of 

fine particles. The data was taken from U.S. EPA's Clean Air Markets database.1

As part of the NOx SIP Call, the states were required to adopt into their rules a budget for all 

large EGUs. Indiana’s budget is referenced in 326 IAC 10-4. The budget represents a statewide 

cap on NOx emissions. Although each unit is allocated emissions based upon historic heat input, 

utilities can meet this budget by over-controlling certain units or purchasing credits from the 

market to account for overages at other units. To summarize, NOx emissions have dramatically 

decreased over the years represented on these graphs. 

These emissions, capped by the state rule, are expected to remain near these levels throughout 

the maintenance period covered by this request. The state cap for the NOx SIP Call remained in 

place through 2008, at which time the Clean Air Interstate Rule (CAIR) program superseded it. 

CAIR, issued in March 2005, adopted by the Indiana Air Pollution Control Board on November 

1, 2006, and implemented beginning in 2010, will continue to reduce regional EGU NOx

 

1

 http://www.epa.gov/airmarkets 

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

2002 2005 2008

Tons per Year

Direct Fine Particles

Year
23

emissions statewide by approximately another 17% by 2015 and 57% for EGU SO2 emissions by 

2015. The D.C. Circuit court’s vacatur of CAIR in July of 2008 and subsequent remand without 

vacatur of CAIR in December of 2008 directs U.S. EPA to revise the CAIR rule in the future. 

The proposed Clean Air Transport Rule (CAIR’s replacement rule) will result in similar or 

greater emission reductions than assumed within the current emission inventories once it is 

implemented. 

There are three EGUs located in Indiana’s portion of the nonattainment area: The Northern 

Indiana Public Service Company (NIPSCO) – Bailly Generating Station, Dominion Resources – 

State Line Generating Plant, and British Petroleum – Whiting Clean Energy Power Plant. 

Graphs 4.13 and 4.15 depict the trends in NOx and SO2 emissions from EGUs in Lake and Porter 

counties, Indiana for the years 1999 through 2009. As the result of a recent settlement with U.S. 

EPA to resolve violations of the CAA’s new source review requirements, NIPSCO has agreed to 

upgrade existing pollution control equipment, as well as install additional pollution control 

equipment at three of its four coal-fired power plants located in Northwest Indiana (i.e. Bailly, 

Michigan City, and R.H. Schafer Generating Stations) to comply with stringent NOx and SO2

emission rates and annual tonnage limitations. The settlement also requires NIPSCO to optimize 

existing PM pollution control equipment to meet unit-specific emissions and permanently retire 

its fourth facility, the Dean H. Mitchell Generating Station. The Dean H. Mitchell Generating 

Station has been out of operation since 2002 and its permanent retirement will ensure that the 

facility does not restart without proper permitting under the CAA. Graphs 4.13 and 4.15 depict 

the trends in NOx and SO2 EGU emissions in Lake and Porter counties, Indiana for the years 

1999 through 2009. Graphs 4.14 and 4.16 depict the trends in statewide NOx and SO2 EGU 

emissions for the years 1999 through 2009. Graphs and data tables of emissions from the EGU 

source category can be found in Appendix D. 

Graph 4.13 

NOx Emissions from EGUs, Lake and Porter Counties, Indiana, 1999 to 2009 

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

Tons per Year

Nitrogen Oxides

Year
24

Graph 4.14

Indiana Statewide NOx Emissions from EGUs, 1999 to 2009 

Graph 4.15 

SO2 Emissions from EGUs, Lake and Porter Counties, Indiana, 1999 to 2009 

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

400,000

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

Tons per Year

Nitrogen Oxides Year

0

3,000

6,000

9,000

12,000

15,000

18,000

21,000

24,000

27,000

30,000

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

Tons per Year

Sulfur Dioxide

Year
25

Graph 4.16

Indiana Statewide SO2 Emissions from EGUs, 1999 to 2009 

4.2 Base Year Inventory

IDEM prepared a comprehensive inventory for the Chicago Area, including area, mobile, 

nonroad, and point sources for direct PM2.5, NOx, and SO2 for 2005 and 2008 (the years with the 

most complete emissions inventory available at this time). The 2008 emission inventory 

represents a base year for maintenance purposes. The 2007 implementation rule for the annual 

standard for fine particles states that NOx, SO2, and direct PM2.5 are the regulated precursors of 

fine particles. Ammonia and VOCs are not required to be addressed unless the state or U.S. EPA 

make a technical demonstration that emissions of these pollutants from sources in the state 

significantly contribute to PM2.5 concentrations in a given nonattainment area. U.S. EPA and 

IDEM have not determined ammonia or VOCs are significant contributors to fine particles 

formation in Indiana. IDEM’s 2008 base year inventory was developed as follows: 

 Area sources were extrapolated from the Indiana 2005 periodic inventory submitted to 

U.S. EPA. 

 Mobile source emissions were calculated from MOBILE6.2 model-produced emission 

factors and data extracted from the region’s travel-demand model. These emissions were 

then interpolated as needed to determine 2008 base year values. 

 Point source information was compiled from IDEM’s emissions inventory database and 

U.S. EPA's Clean Air Markets acid rain database. 

 Biogenic emissions are not specifically included in these summaries, but are included in 

the photochemical modeling results presented in Section 7.0. 

0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

800,000

900,000

1,000,000

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009

Tons per Year

Sulfur Dioxide

Year
26

 Nonroad emissions were extrapolated from the 2005 National Emissions Inventory 

(NEI). To address concerns about the accuracy of some of the categories in U.S. EPA’s 

nonroad emissions model, Lake Michigan Air Directors Consortium (LADCO) 

contracted with two companies to review the base data and make recommendations. One 

of the contractors also estimated emissions for two nonroad categories not included in 

U.S. EPA's nonroad model. Emissions were estimated for commercial marine vessels 

and railroads. The recreational motorboat population and spatial surrogates (used to 

assign emissions to each) were also significantly updated. The populations for the 

construction equipment category were also reviewed and updated based upon surveys 

completed in the Midwest and the temporal allocation for agricultural sources was also 

updated. A new nonroad estimation model was provided by U.S. EPA for the 2005 

analysis. 

● Area, nonroad, mobile, and point source emissions data referenced for Illinois’ portion of 

the Chicago Area were taken directly from the Chicago Maintenance Plan. This 

inventory was prepared using similar methodologies. Emissions for the year 2005 were 

interpolated from the 2002 and 2008 emissions data. 

Appendix C contains data tables and graphs of these emissions. 

4.3 Emission Projections

In consultation with U.S. EPA and other stakeholders, IDEM selected the year 2025 as the 

maintenance year for this redesignation request. This document contains projected emission 

inventories for 2015, 2020, and 2025. These emission projections were prepared by IDEM, with 

assistance from LADCO, Illinois EPA, and the Northwest Indiana Regional Planning 

Commission. 

The detailed 2015, 2020, and 2025 emission inventory for the Chicago Area can be found in 

Appendix E. Emission trends are an important gauge for continued compliance with the annual 

standard for fine particles. Therefore, IDEM performed an initial comparison of the inventories 

for the base year of 2008, interim years of 2015 and 2020, and maintenance year of 2025 for 

Lake and Porter counties, Indiana, as well as the entire Chicago Area. 

The 2005 LADCO modeling inventory was used as the basis for estimated emissions for Lake 

and Porter counties, Indiana for the years 2008, 2015, 2020, and 2025, using LADCO’s growth 

factors, for all sectors except point sources (electric generating units and non-electric generating 

units). Point source emissions for 2005 and 2008 were compiled from Indiana’s annual emission 

inventory database. The 2015 interim year emissions were interpolated based on the 2009 and 

2018 LADCO modeling inventory, using LADCO’s growth factors, for all sectors. The 2020 

interim year emissions and the 2025 maintenance year emissions were extrapolated from the 

2009 and 2018 LADCO modeling inventory. 

The projected emission inventories for 2015, 2020, and 2025 for Illinois’ portion of the Chicago 

Area were taken directly from the Chicago Maintenance Plan. 
27

Graphs 4.17, 4.18, 4.19, and 4.20 visually compare 2005 and 2008 (base year) NOx, SO2, and 

direct PM2.5 county total estimated emissions with the 2015, 2020, and 2025 projected emissions 

for Lake and Porter counties, Indiana. Graphs 4.21, 4.22, 4.23, and 4.24 visually compare the 

2005 and 2008 (base year) NOx, SO2, and direct PM2.5 county total estimated emissions with the 

2015, 2020, and 2025 projected emissions for the entire Chicago Area. Mobile source emission 

inventories are further described in Section 5.0. In addition to LADCO’s estimates, point source 

emissions were projected based upon the statewide EGU NOx budgets from Indiana’s NOx rule. 

EGU emission estimates for 2015, 2020, and 2025 were projected using the budgets from the 

proposed Transport Rule and Options 1 and 2 from the recent Notice of Data Availability. Since 

it is likely that the finalized rule will include a budget approximating one of these, IDEM used 

the option with the highest allotment each for the NIPSCO – Bailly Generating Station, 

Dominion Resources – State Line Generating Plant, and British Petroleum – Whiting Clean 

Energy Power Plant to develop conservative projections. These allowances cover 2014 forward, 

so the same projections were used for all three years. Further, the consent decree provides 

overall caps for all NIPSCO facilities in Northwest Indiana. The emissions allowed under these 

caps are similar to those in the Transport Rule. Therefore, IDEM is confident that emissions in 

these three years will be close to or below the projections. Graphs and data tables of emissions 

from the EGU source category can be found in Appendix D. 

Graph 4.17 

Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected NOx

Emissions, Lake and Porter Counties, Indiana 

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

2005 2008 2015 2020 2025

Tons per Year

Nitrogen Oxides Year
28

Graph 4.18 

Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected SO2

Emissions, Lake and Porter Counties, Indiana 

Graph 4.19 

Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected Direct PM2.5

Emissions, Lake and Porter Counties, Indiana 

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

2005 2008 2015 2020 2025

Tons per Year

Sulfur Dioxide

Year

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

2005 2008 2015 2020 2025

Tons per Year

Direct Fine Particles

Year
29

Graph 4.20 

Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected NOx, SO2, and 

Direct PM2.5 Emissions, Lake and Porter Counties, Indiana 

Graph 4.21 

Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected NOx

Emissions, Entire Chicago Area 

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

2005 2008 2015 2020 2025

Tons per Year

Nitrogen Oxides Sulfur Dioxide Direct Fine Particles

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

400,000

2005 2008 2015 2020 2025

Tons per Year

Nitrogen Oxides

Year
30

Graph 4.22 

 Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected SO2

Emissions, Entire Chicago Area 

Graph 4.23 

Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected Direct PM2.5

Emissions, Entire Chicago Area 

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

160,000

180,000

200,000

2005 2008 2015 2020 2025

Tons per Year

Sulfur Dioxide Year

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

2005 2008 2015 2020 2025

Tons per Year

Direct Fine Particles

Year
31

Graph 4.24 

Comparison of 2005 and 2008 Estimated and 2015, 2020, and 2025 Projected NOx, SO2, 

and Direct PM2.5 Emissions, Entire Chicago Area 

NOx emissions within Lake and Porter counties, Indiana are projected to decline by 41.23% 

between 2008 and 2025. NOx emissions within the Chicago Area are projected to decline by 

46.46% between 2008 and 2025. Emission reduction benefits from U.S. EPA rules covering the 

NOx SIP Call, Tier 2 Motor Vehicle Emission Standards and Gasoline Sulfur Control 

Requirements, Heavy-Duty Highway Engine Rule, and the Nonroad Diesel Engine Rule are 

factored into the changes. Additionally, due to implementation of the NOx SIP Call across the 

eastern United States, NOx and fine particle levels entering the Chicago Area will also be 

decreased. SO2 emissions within Lake and Porter counties, Indiana are projected to decrease by 

35.54% between 2008 and 2025. SO2 emissions within the Chicago Area are projected to 

decline by 34.73% between 2008 and 2025. Direct PM2.5 emissions within Lake and Porter 

counties, Indiana are projected to decrease by 6.74% between 2008 and 2025. Direct PM2.5 

emissions within the Chicago Area are projected to decline by 2.69% between 2008 and 2025. 

0

50,000

100,000

150,000

200,000

250,000

300,000

350,000

400,000

2005 2008 2015 2020 2025

Tons per Year

Nitrogen Oxides Sulfur Dioxide Direct Fine Particles

Year
32

Table 4.1 

Comparison of 2008 Estimated and 2025 Projected Emission Estimates, 

Lake and Porter Counties, Indiana (Tons per Year) 

 2008 2025 Change % Change 

NOx 59,581.74 35,013.79 -24,567.95 41.23% decrease 

SO2 56,198.68 36,787.24 -19,411.44 35.54% decrease 

Direct PM2.5 7,250.93 6,762.10 -488.83 6.74% decrease 

Table 4.2 

Comparison of 2008 Estimated and 2025 Projected Emission Estimates, 

Entire Chicago Area (Tons per Year)

 2008 2025 Change % Change 

NOx 278,649.74 149,198.79 -129,450.95 46.46% decrease 

SO2 152,367.68 99,453.24 -52,914.44 34.73% decrease 

Direct PM2.5 25,767.93 25,074.10 -693.83 2.69% decrease 

4.4 Demonstration of Maintenance

Quality assured ambient air quality data from all the monitoring sites indicate that air quality in 

Indiana’s portion of the nonattainment area met the annual standard for fine particles for the 

three-year period ending in 2010. U.S. EPA’s Redesignation Guidance states, “A state may 

generally demonstrate maintenance of the NAAQS by either showing that future emissions of a 

pollutant or its precursors will not exceed the level of the attainment inventory, or by modeling 

to show that the future mix of sources and emission rates will not cause a violation of the 

NAAQS.” Section 3.0 of this document shows that the Chicago Area has in fact measured 

attainment for fine particles for the three consecutive periods ending in 2008, 2009, and 2010. 

Additionally, emission projections outlined in Section 4.0 of this document clearly illustrate that 

regional NOx, SO2, and direct PM2.5 emissions in the area will continue to decline leading to 

local reductions between 2008 (base year) and 2025 (maintenance plan horizon). Section 7.0 

further discusses the implications of these emission trends and provides an analysis to support 

these conclusions. 

 

In Indiana, major point sources in all counties are required to submit air emissions information 

once every three years, or annually, if the NOx or SO2 potential to emit is greater than 2,500 tons 

per year in accordance with the Emission Reporting Rule, 326 IAC 2-6. IDEM prepares a new 

periodic inventory for all precursor emission sectors every three years. These precursor emission 

inventories will be prepared for 2011, 2014, and 2017, as necessary, to comply with the 

inventory reporting requirements established in the CAA. Emissions information will be 

compared to the 2008 base year and the 2025 projected maintenance year inventories to assess 

emission trends, as necessary, to assure continued compliance with the annual standard for fine 

particles. 

 
33

4.5 Permanent and Enforceable Emission Reductions

Permanent and enforceable reductions of NOx and SO2 have contributed to the attainment of the 

annual standard for fine particles. Some of these reductions were due to the implementation of 

the NOx SIP Call rule and some were due to the application of tighter federal standards on motor 

vehicles and fuels. 

Section 6.0 identifies the emission control measures specific to Lake and Porter counties, 

Indiana, as well as the implementation status of each measure. 

4.6 Provisions for Future Updates 

 

As required by Section 175A(b) of the CAA, Indiana commits to submit to the Administrator, 

eight years after redesignation, an additional revision of this SIP. The revision will contain 

Indiana's plan for maintaining the national primary fine particles air quality standard for ten years 

beyond the first ten-year period after redesignation. 

5.0 TRANSPORTATION CONFORMITY BUDGETS

U.S. EPA requirements outlined in 40 CFR 93.118(e)(4) stipulate that motor vehicle emission 

budgets (MVEBs) for direct PM2.5 and NOx be established as part of a SIP. The MVEBs are 

necessary to demonstrate conformance of transportation plans and improvement programs with 

the SIP. 

5.1 On-Road Emission Estimates

The Northwest Indiana Regional Planning Commission (NIRPC) is the Metropolitan Planning 

Organization (MPO) for the area that includes Lake, Porter, and LaPorte counties. This 

organization maintains a travel demand forecast model that is used to simulate the traffic in the 

area and are used to predict what the traffic would be like in future years given growth 

expectations. They are also used mostly to identify where travel capacity will be needed and to 

determine the infrastructure requirements necessary to meet that need. It is also used to support 

the calculation of mobile source emissions. The travel demand forecast model is used to predict 

the total daily vehicle miles traveled (VMT) and the U.S. EPA software program, MOBILE6.2, 

is used to calculate per mile emissions. The product of these two outputs, once combined, is the 

estimated total amount of pollution emitted by the on-road vehicles for the area analyzed. 

5.2 Overview

Broadly described, MOBILE6.2 is used to determine “emission factors”, which are the average 

emissions per mile (grams/mile) for fine particles and fine particle precursors (NOx, SO2, and 

direct PM2.5). There are numerous variables that can affect the emission factors. The vehiclefleet (vehicles on the road) age and the vehicle types have a major effect on the emission factors. 

The facility-type on which vehicles are traveling (MOBILE6.2 facility types are Freeway, 

Arterial, Local, and Ramp) and the vehicle speeds also affect the emission factor values. 
34

Meteorological factors such as air temperature and humidity affect emission factors, as does fuel 

type, such as low Reid Vapor Pressure gasoline. These data are estimated using the best 

available data to create emission factors for PM2.5 precursors (NOx, SO2, and direct PM2.5). 

After emission factors are determined, they must be multiplied by the VMT to determine the 

quantity of vehicle-related emissions. This information is derived from the travel demand 

model. 

It should be noted that each year analyzed will have different emission factors, volumes, speeds, 

and likely results in additional modeling. MOBILE6.2 input and output files are found in 

Appendix F. 

5.3 Analysis Years

The travel demand model contains road networks that are time specific. The NIRPC has 

modeled the years 2005, 2010, 2020, and 2030. Information, including emissions, has also been 

interpolated from 2005 and 2010 for the year 2008, from 2010 and 2020 for the years 2015 and 

2016, and from 2020 and 2030 for the year 2025. This Redesignation Petition provides emission 

inventory estimates for 2002, 2005, 2008, 2015, 2020, and 2025 to meet the requirements 

specified by the CAA and U.S. EPA. The emission estimates outlined in Section 4.0 of this 

document reference the mobile source emissions data contained in Table 5.1. 

5.4 Emission Estimates

Table 5.1 outlines on-road emission estimates for the entire nonattainment area for the years 

2005, 2008 (base/attainment year), 2015, 2016, 2020 (interim years), and 2025 (horizon year). 

 Table 5.1 

 Emission Estimates for On-Road Mobile Sources 

Chicago Area 2005 2008 2015 2016 2020 2025 

Direct PM2.5 (tons/year) 2,443.50 1,816.00 1,231.00 1,137.00 1,043.00 1,064.00 

NOx (tons/year) 133,623.50 99,627.00 49,746.00 39,424.00 29,102.00 23,687.00

Lake and Porter Counties, 

IN subtotal 

Direct PM2.5 (tons/year) 229.39 187.09 136.61 132.15 114.32 115.39 

NOx (tons/year) 14,095.55 10,703.81 5,723.67 5,179.87 3,004.68 2,534.95 

Lake and Porter Counties, 

IN subtotal% 

Direct PM2.5 (tons/year) 9.39% 10.30% 11.10% 11.62% 10.96% 10.84% 

NOx (tons/year) 10.55% 10.74% 11.51% 13.14% 10.32% 10.70% 

 
35

5.5 Motor Vehicle Emission Budget

Table 5.2 contains the motor vehicle emission budget for the Indiana portion of the 

nonattainment area for the years 2016 and 2025. These MVEBs are intended to be direct 

replacements of those provided in Indiana’s previous submittal. 

Table 5.2 

Motor Vehicle Emission Budgets for Lake and Porter Counties 

2016 2025 

PM2.5 (tons/year) 145.37 132.70 

NOx (tons/year) 5,697.86 2,915.19 

Consistent with the federal implementation rule for fine particles, Indiana does not consider 

mobile source SO2 to be a significant contributor to fine particles for this nonattainment area, as 

mobile source SO2 constitutes less than one percent (<1%) of the area’s total anthropogenic 

emissions. 

These budgets include emission estimates calculated for 2016 and 2025. The emission estimates 

are derived from the MPO’s travel demand models and MOBILE6.2, as described above. 

Through the interagency consultation process, it was determined that an interim budget year of 

2016, in addition to the horizon year budget of 2025, would be appropriate. The interagency 

consultation group approved a ten percent (10%) safety margin for PM2.5 and NOx mobile source 

emissions estimates for the year 2016 and a fifteen percent (15%) safety margin for PM2.5 and 

NOx mobile source emissions estimates for the year 2025. Margins of safety are used to 

accommodate the wide array of assumptions that are factored into the calculation process. Since 

assumptions change over time, it is necessary to have a margin of safety that will accommodate 

the impact of refined assumptions in the process. 

The rule at 40 CFR 93.101 defines safety margin as the amount by which the total projected 

emissions from all sources of a given pollutant are less than the total emissions that would satisfy 

the applicable requirement for reasonable further progress, attainment, or maintenance. When 

compared to the overall safety margin as defined by 40 CFR 93.101, it is evident this allocation 

to mobile sources is significantly below the total safety margin for all sources in Lake and Porter 

counties, Indiana as detailed in Table 4.1. 

5.6 Commitment to Amend Motor Vehicle Emission Budgets Using Motor Vehicle Emission

 Simulator (MOVES)

On March 2, 2010, U.S. EPA published a Notice of Availability for the MOVES model. IDEM 

is committed to submitting a revision to the MOBILE6.2 developed MVEBs using the MOVES 

model as soon as possible and well in advance of the March 2, 2012, expiration of the 

transportation conformity “grace period.” IDEM recognizes that U.S. EPA will allow the 

MOBILE6.2 budgets to be replaced through an adequacy notice in place of a full publication to 

the Federal Register. 

 
36

All methodologies, latest planning assumptions, margins of safety, and MOVES model 

commitments were determined appropriate through the interagency consultation 

process. 

6.0 CONTROL MEASURES AND REGULATIONS

This section provides specific information on the control measures that have been or will be 

implemented in Lake and Porter counties, Indiana, including CAA requirements and additional 

state or local measures implemented beyond CAA requirements. 

6.1 Reasonably Available Control Technology (RACT)

 As required by Section 172 of the CAA, in the mid-1990s, Indiana promulgated rules requiring 

RACT for emissions of VOCs. There were no specific rules required by the CAA, such as 

RACT for existing sources, beyond statewide rules. Statewide RACT rules have applied to all 

new sources locating in Indiana since that time. The Indiana rules are found in 326 IAC 8. The 

following is a listing of applicable rules: 

 326 IAC 8-1-6 BACT for Non-Specific Sources 

326 IAC 8-2 Surface Coating Emission Limitations 

326 IAC 8-3 Solvent Degreasing Operations 

326 IAC 8-4 Petroleum Sources 

326 IAC 8-5 Miscellaneous Operation 

326 IAC 8-6 Organic Solvent Emission Limitations 

Since Lake and Porter counties, Indiana attained the annual standard for fine particles prior to an 

Attainment SIP or RACT SIP being due, and since the Implementation Rule for fine particles 

stipulates that states are only required to draft and implement RACT rules for the precursor 

emission reductions necessary to attain the standard, no further RACT rules are required for this 

area. These Indiana rules are CAA requirements already in the SIP and provide secondary 

benefits for PM2.5. 

6.2 Implementation of Past SIP Revisions

The Chicago Area was designated nonattainment for the annual standard for fine particles in 

2003 and the area has now attained the standard well in advance of its attainment deadline of 

2010. As a result, Indiana is no longer required to develop and submit an Attainment SIP or 

RACT SIP for this area under the annual NAAQS for fine particles. 

6.3 Nitrogen Oxides Rule

The U.S. EPA NOx SIP Call required twenty-two states to adopt rules that would result in 

significant emission reductions from large EGUs, industrial boilers, and cement kilns in the 

eastern United States. The Indiana rule was adopted in 2001. Beginning in 2004, this rule 
37

accounts for a reduction of approximately 31% of all NOx emissions statewide compared to 

previous uncontrolled years. 

Twenty-one other states have also adopted these rules. The result is that significant reductions 

have occurred regionally and within the nonattainment area because of the number of affected 

units within the region. From Graphs 4.13 and 4.14, it can be seen that emissions covered by this 

program have been trending downward since 1999. Table 6.1, compiled from data taken from 

the U.S. EPA Clean Air Markets web site, quantifies the gradual NOx reductions that have 

occurred in Indiana as a result of Title IV (Acid Rain) of the CAA and the NOx SIP Call Rule. 

The NOx SIP Call cap stayed in place through 2008, at which time the caps in the CAIR 

program superseded it. Since CAIR is a regional cap and trade program, it cannot be predicted at 

this time what affect this will have on EGUs located in the nonattainment area or other upwind 

counties. 

Further, U.S. EPA published Phase II of the NOx SIP Call that established a budget for large 

(emissions of greater than 1 ton per day) stationary internal combustion engines. In Indiana, the 

rule decreases emissions statewide from natural gas compressor stations by 4,263 tons during the 

ozone season (April through September). The Indiana Phase II NOx SIP Call Rule became 

effective February 26, 2006 and implementation began in 2007. 

Table 6.1 

Trends in EGU NOx Emissions Statewide in Indiana 

Year NOx Emissions (tons/year) 

1999 347,216.5 

2000 334,522.1 

2001 315,419.7 

2002 281,146.1 

2003 260,980.0 

2004 224,311.3 

2005 207,981.6 

2006 202,728.0 

2007 196,553.1 

2008 196,134.5 

2009 110,968.9 

Budget 2009-2014 108,935 

Budget 2015 and later 90,779 

6.4 Measures Beyond Clean Air Act SIP Requirements

Reductions in fine particle precursor emissions have occurred, or are anticipated to occur, as a 

result of local and federal programs. These additional control measures include those listed in 

this section. 

 
38

Tier 2 Vehicle Standards2

Federal Tier 2 motor vehicle standards require all passenger vehicles in a manufacturer’s fleet, 

including light-duty trucks and sport utility vehicles (SUVs), to meet an average standard of 0.07 

grams of NOx per mile. Implementation began in 2004 and was completed in 2007. The Tier 2 

standards also cover passenger vehicles over 8,500 pounds gross vehicle weight rating (larger 

pickup trucks and SUVs), which are not covered by the current Tier 1 standards. For these 

vehicles, the standards were phased in beginning in 2008, with full compliance in 2009. The 

new standards require vehicles to be 77% to 95% cleaner than those on the road prior to the 

program. The Tier 2 standards also reduced the sulfur content of gasoline to 30 parts per million 

(ppm) beginning in January 2006. Most gasoline sold in Indiana prior to January 2006 had a 

sulfur content of about 500 ppm. Sulfur occurs naturally in gasoline, but interferes with the 

operation of catalytic converters on vehicles resulting in higher NOx emissions. Lower sulfur 

gasoline is necessary to achieve the Tier 2 vehicle emission standards. 

Heavy-Duty Gasoline and Diesel Highway Vehicle Standards3

New U.S. EPA standards designed to reduce NOx and VOC emissions from heavy-duty gasoline 

and diesel highway vehicles took effect in 2004. A second phase of standards and testing 

procedures that began in 2007, reduced fine particles from heavy-duty highway engines and also 

reduced highway diesel fuel sulfur content to 15 ppm since the sulfur can damage emission 

control devices. The total program is expected to achieve a 90% reduction in direct PM2.5

emissions and a 95% reduction in NOx emissions for these new engines using low sulfur diesel, 

compared to existing engines using higher sulfur content diesel. There will also be SO2

reductions from these rules. U.S. EPA has not quantified the expected reductions. 

Large Nonroad Diesel Engine Standards4

In May 2004, U.S. EPA promulgated new rules for large nonroad diesel engines, such as those 

used in construction, agricultural, and industrial equipment, to be phased in between 2008 and 

2014. The nonroad diesel rules also reduce the allowable sulfur in nonroad diesel fuel by over 

99%. Prior to 2006, nonroad diesel fuel averaged approximately 3,400 ppm sulfur. This rule 

limited nonroad diesel sulfur content to 500 ppm by 2006 with a further reduction to 15 ppm by 

2010. The combined engine and fuel rules will reduce NOx and PM emissions from large 

nonroad diesel engines by over 90%, compared to current nonroad engines using higher sulfur 

content diesel. 

Nonroad Spark-Ignition Engines and Recreational Engine Standards

This new standard, effective in July 2003, regulates NOx, VOCs, and carbon monoxide (CO) for 

groups of previously unregulated nonroad engines. The new standard applies to all new engines 

sold in the United States and imported after the standards went into effect. The standard applies 

to large spark-ignition engines (forklifts and airport ground service equipment), recreational 

 

2 http://www.epa.gov/fedrgstr/EPA-AIR/2000/February/Day-10/a19a.htm 3 http://www.epa.gov/fedrgstr/EPA-AIR/1997/October/Day-21/a27494.htm 4 http://www.epa.gov/fedrgstr/EPA-AIR/1998/October/Day-23/a24836.htm 
39

vehicles (off-highway motorcycles and all-terrain vehicles), and recreational marine diesel 

engines. The regulation varies based upon the type of engine and vehicle. 

The emissions from large spark-ignition engines contribute to ozone formation and ambient CO 

and PM2.5 levels in urban areas. Tier 1 of this standard was implemented in 2004 and Tier 2 

started in 2007. Like the large spark-ignition engines, emissions from recreational vehicles 

contribute to ozone and fine particles formation and ambient CO and PM2.5 levels. For Model 

Year 2006 off-highway motorcycles and all-terrain vehicles, at least 50% of a manufacture’s 

fleet was required to meet the new exhaust emissions standard and 100% of the fleet was 

required to meet the standards in 2007. Recreational marine diesel engines over 37 kilowatts are 

used in yachts, cruisers, and other types of pleasure craft. Emissions from recreational marine 

engines contribute to ozone formation and PM levels, especially surrounding marinas. 

When all of the nonroad spark-ignition engines and recreational engine standards are fully 

implemented, an overall 72% reduction in VOC, 80% reduction in NOx, and 56% reduction in 

CO emissions are expected by 2020. 

Reciprocating Internal Combustion Engine Standards5 

This new standard, effective in May 2010, regulates emissions of air toxics from existing diesel 

powered stationary reciprocating internal combustion engines that meet specific site rating, age, 

and size criteria. These engines are typically used at industrial facilities (e.g. power, chemical, 

and manufacturing plants) to generate electricity for compressors and pumps and to produce 

electricity to pump water for flood and fire control during emergencies. 

The standard applies to stationary diesel engines: (1) used at area sources of air toxics and 

constructed or reconstructed before June 12, 2006; (2) used at major sources of air toxics, having 

a site rating of less than or equal to 500 horsepower, and constructed or reconstructed before 

June 12, 2006; and, (3) used at major sources of air toxics for non-emergency purposes, having a 

site rating of greater than 500 horsepower, and constructed or reconstructed before December 19, 

2002. 

Operators of existing engines will be required to: (1) install emissions control equipment that 

would limit air toxics up to 70% for stationary non-emergency engines with a site rating greater 

than 300 horsepower; (2) perform emission tests to demonstrate engine performance and 

compliance with rule requirements; and, (3) burn ultra-low sulfur fuel in stationary nonemergency engines with a site rating greater than 300 horsepower. 

When all of the reciprocating internal combustion engine standards are fully implemented in 

2013, U.S. EPA estimates that emissions from these engines will reduce air toxics by 

approximately 1,000 tons per year (tpy), PM2.5 by 2,800 tpy, CO by 14,000 tpy, and VOC by 

27,000 tpy. 

 

 

5 http://www.epa.gov/ttn/atw/rice/fr03mr10.pdf 
40

Category 3 Marine Diesel Engine Standards6

This new standard, effective in June 2010, promulgates more stringent exhaust emission 

standards for new large marine diesel engines with per-cylinder displacement at or above 30 

liters (commonly referred to as Category 3 compression-ignition marine engines) as part of a 

coordinated strategy to address emissions from all ships that affect U.S. air quality. These 

emission standards are equivalent to those adopted in the amendments to Annex VI to the 

International Convention for the Prevention of Pollution from Ships (MARPOL Annex VI). The 

emission standards apply in two stages—near-term standards for newly built engines will apply 

beginning in 2011; long-term standards requiring an 80% reduction in NOx emissions will begin 

in 2016. 

U.S. EPA is adopting changes to the diesel fuel program to allow for the production and sale of 

diesel fuel with up to 1,000 ppm sulfur for use in Category 3 marine vessels. The regulations 

generally forbid production and sale of fuels with more than 1,000 ppm sulfur for use in most 

U.S. waters, unless operators achieve equivalent emission reductions in other ways. 

U.S. EPA is also adopting provisions to apply some emission and fuel standards to foreignflagged and in-use vessels that are covered by MARPOL Annex VI. 

When this strategy is fully implemented in 2030, U.S. EPA estimates that NOx and PM2.5

emissions in the U.S. will be reduced by approximately 1.2 million tpy and 143,000 tpy, 

respectively. 

Clean Air Interstate Rule (CAIR)

On May 12, 2005, U.S. EPA promulgated the “Rule to Reduce Interstate Transport of Fine 

Particulate Matter and Ozone (Clean Air Interstate Rule); Revisions to Acid Rain Program; 

Revisions to the NOx SIP Call”; Final Rule (70 FR 25162). This rule established the requirement 

for states to adopt rules limiting the emissions of NOx and SO2 and provided a model rule for the 

states to use in developing their rules to meet federal requirements. The purpose of CAIR was to 

reduce interstate transport of precursors to fine particles and ozone. 

CAIR applied to: (1) any stationary, fossil-fuel-fired boiler or stationary, fossil-fuel-fired 

combustion turbine, a generator with a nameplate capacity of more than 25 megawatt electrical 

(MWe) producing electricity for sale; and (2) a unit that qualifies as a cogeneration unit during 

the 12-month period starting on the date that the unit first produces electricity and continues to 

qualify as a cogeneration unit, a cogeneration unit serving at any time a generator with a 

nameplate capacity of more than 25 MWe and supplying in any calendar year more than onethird of the unit’s potential electric output capacity or 219,000 megawatt hours (MWh), 

whichever is greater, to any utility power distribution system for sale. 

 

 

6 http://www.regulations.gov/search/Regs/home.html#documentDetail?R=0900006480ae43a6
41

This rule provides annual state caps for NOx and SO2 in two phases, with the Phase I caps for 

NOx and SO2 starting in 2009 and 2010, respectively. Phase II caps become effective in 2015. 

U.S. EPA is allowing the caps to be met through a cap and trade program if a state chooses to 

participate in the program. 

In response to U.S. EPA’s rulemaking, IDEM adopted a state rule in 2006 based on the model 

federal rule. IDEM’s rule includes annual and seasonal NOx trading programs, and an annual 

SO2 trading program. This rule requires compliance effective January 1, 2009. 

SO2 emissions from power plants in the 28 eastern states and the District of Columbia covered 

by CAIR will be cut by 4.3 million tons by 2009 and reduced by an additional 5.4 million tons in 

2015. NOx emissions will be cut by 1.7 million tons by 2009 and reduced by an additional 1.3 

million tons in 2015. The D.C. Circuit court’s vacatur of CAIR in July of 2008 and subsequent 

remand without vacatur of CAIR in December of 2008 directs U.S. EPA to revise or replace 

CAIR in order to properly address the deficiencies outlined by the court. 

Since the court’s opinion made it clear that CAIR is deficient and must be revised or replaced, 

the program cannot be defined as permanent and enforceable for SIP purposes. On July 6, 2010, 

U.S. EPA proposed the Clean Air Transport Rule to replace CAIR. The Clean Air Transport 

Rule will result in even further benefits above and beyond CAIR than what is assumed within the 

emission inventories and modeling. 

Together, these rules will substantially reduce local and regional sources of fine particle 

precursors. The modeling analyses discussed in Section 7.0 include these rules and show the 

reductions in annual fine particle concentrations expected to result from the implementation of 

these rules. 

6.5 Controls to Remain in Effect

IDEM commits to maintain the control measures listed above after redesignation, or submit to 

U.S. EPA, as a SIP revision, any changes to its rules or emission limits applicable to NOx, SO2, 

or direct PM2.5 sources as required for maintenance of the annual standard for fine particles in 

Lake and Porter counties, Indiana. 

Indiana, through IDEM’s Office of Air Quality and its Compliance and Enforcement Branch, has 

the legal authority and necessary resources to actively enforce any violations of its rules or 

permit provisions. After redesignation, it intends to continue enforcing all rules that relate to the 

emission of fine particles and fine particle precursors in Lake and Porter counties, Indiana. 

6.6 New Source Review Provisions

Indiana has a long standing and fully implemented New Source Review (NSR) program that is 

outlined in rule 326 IAC 2. The rule includes provisions for the Prevention of Significant 

Deterioration (PSD) permitting program in 326 IAC 2-2 and the emissions offset rule in 326 IAC 
42

2-3. Indiana's PSD program was conditionally approved on March 3, 2003 (68 FR 9892) and 

received final approval on May 20, 2004 (69 FR 29071) by U.S. EPA as part of the SIP. 

Any emission unit that is not listed in the 2005 emission inventory, or for which credit through 

the shutdown or curtailment of operations was taken in demonstrating attainment, will not be 

allowed to construct, reopen, modify, or reconstruct without meeting all applicable permit rule 

requirements. The review process will be identical to that used for new sources. Once the area 

is redesignated, OAQ will implement NSR through the PSD program, which requires an air 

quality analysis to evaluate whether the new source will threaten the NAAQS. 

7.0 MODELING AND METEOROLOGY 

Although U.S. EPA’s Redesignation Guidance does not require modeling for fine particle 

nonattainment areas seeking redesignation, extensive modeling has been performed for the 

Chicago Area to determine the effect of national emission control strategies on fine particle 

levels. These modeling analyses determined that the Chicago Area, including Lake and Porter 

counties in Northwest Indiana, are significantly impacted by regional transport of fine particles 

and its precursors, and that regional SO2 and NOx reductions are an effective way to attain the 

annual standard for fine particles in this area. Future year modeled annual fine particle 

concentrations are expected to be reduced by 2% to 9% from baseline design values. Examples 

of these modeling analyses are described in this section and can also be found in Appendix H. 

7.1 Summary of Modeling Results to Support Rulemakings

U.S. EPA Modeling for Clean Air Transport Rule 20107

U.S. EPA performed modeling to support the emission reductions associated with the proposed 

Clean Air Transport Rule. U.S. EPA used the Comprehensive Air Quality Model with Extension 

(CAMx version 5), applied to the 2005 meteorology, as processed by the Mesoscale Model 

(MM5), version 3.7.4. Emissions input into CAMx included SO2, NOx, VOCs, NH3, and direct 

PM2.5 for 2005. The modeling was based on the annual fine particle design values calculated 

from 2003 through 2005, 2004 through 2006, and 2005 through 2007. Future year modeling was 

conducted, which included the Chicago Area, and the future year design values for 2012 and 

2014 were evaluated for attainment of the annual NAAQS for fine particles of 15 μg/m3

, as 

shown in Table 7.1. Fine particle concentrations are accounted for by modeling both the base 

future year emissions and then the emission reductions associated with the Clean Air Transport 

Rule. U.S. EPA found model performance met suggested benchmark performance goals within 

or close to the ranges found in other comparable modeling applications. 

 

 

7 http://www.epa.gov/airquality/transport/pdfs/TR_AQModeling_TSD.pdf
43

Table 7.1 

Clean Air Transport Rule Modeling Results from U.S. EPA – 2010 

SITE ID SITE NAME COUNTY 

Design 

Value 

2003 – 2007 

(μg/m3) 

Future Design 

Value 

2012 Base 

(μg/m3) 

Future Design 

Value 

2014 Base 

(μg/m3) 

18-089-0006 East Chicago - Franklin School Lake 14.27 13.83 13.35 

18-089-0027 Griffith Lake 13.83 13.44 12.97 

18-089-1003 Gary – Ivanhoe School Lake 14.02 13.61 13.15 

18-089-2004 Hammond - Purdue Lake 14.05 13.66 13.19 

18-089-2010 Hammond – Clark High School Lake 13.89 13.47 12.99 

18-127-0020 Ogden Dunes Porter 12.66 12.18 11.73 

18-127-0024 Dunes National Lakeshore Porter 13.21 12.73 12.26 

17-031-0022 Chicago – Washington High School Cook - IL 15.21 14.70 14.22 

17-031-0050 Chicago – Southeast Police Station Cook - IL 14.81 14.32 13.82 

17-031-0052 Chicago – Mayfair Pump Station Cook - IL 15.75 15.16 14.64 

17-031-0057 Chicago – Springfield Pump Station Cook - IL 15.03 14.50 13.98 

17-031-0076 Chicago – Com Ed Maintenance Building Cook - IL 14.89 14.41 13.87 

17-031-2001 Blue Island Cook - IL 14.77 14.28 13.8 

17-031-3301 Summit Cook - IL 15.24 14.73 14.2 

17-031-4007 Des Plaines Cook - IL 12.78 12.45 11.92 

17-031-4201 Northbrook Cook - IL 12.76 12.44 11.91 

17-031-6005 Cicero Cook - IL 15.48 14.92 14.40 

17-043-4002 Naperville Du Page - IL 13.82 13.51 12.95 

17-089-0003 Elgin Kane - IL 13.32 12.94 12.36 

17-089-0007 Aurora Kane - IL 14.34 13.95 13.39 

17-097-1007 Zion Lake - IL 11.81 11.57 11.06 

17-111-0001 Cary McHenry - IL 12.40 12.08 11.53 

17-197-1002 Joliet Will - IL 13.63 13.33 12.79 

17-197-1011 Braidwood Will - IL 11.52 11.26 10.77 

Modeling results show that the base future year modeling with emission reductions from the 

Clean Air Transport Rule will account for a 0.4 to 0.5 μg/m3

 decrease in concentrations for 2012, 

as well as a 0.9 to 1.0 μg/m3

 decrease in concentrations for 2014 in the Chicago Area. 

Only one PM2.5 monitor in the Chicago Area had a modeled design value above the annual 

standard for fine particles for 2012. The Chicago - Mayfair Pump Station monitor (ID 17-031-

0052) had a 2003 through 2007 design value of 15.75 μg/m3

. Review of this monitor’s most 

current 2006 through 2010 design value shows that the design value has decreased by 2.42 μg/m3

to 13.33 μg/m3

. Therefore, modeling results should fall by a similar value and be well below the 

annual standard for fine particles. Design values from 2003 through 2007 to 2006 through 2010 

have fallen by an average of 2.1 μg/m3

 throughout the Chicago Area. Graph 7.1 shows the 

downward trend of the design values from 2000 through 2010 from the PM2.5 monitors located in 

Lake and Porter counties, Indiana. In fact, all design values are below the annual NAAQS for 

fine particles. 

 
44

Graph 7.1 

PM2.5 Design Value Trends for Lake and Porter Counties, Indiana, 2000 to 2010 

Results of the U.S. EPA’s Clean Air Transport Rule modeling show that the Chicago Area will 

attain the annual fine particle NAAQS in 2012 with modeled impacts reduced by 3% to 4%, and 

will remain below 15 μg/m3. With further reductions projected in the Clean Air Transport Rule 

for 2014, all design values decrease by 6% to 7% and the area will continue to attain the annual 

NAAQS for fine particles. 

LADCO Modeling for Clean Air Interstate Rule (CAIR)

LADCO conducted modeling to determine the impact of CAIR in the Midwest. LADCO’s 

modeling used the CAMx model applied to the year 2005 meteorology, as processed by the 

MM5. Emissions input into CAMx included SO2, NOx, VOCs, NH3, and direct PM2.5 for 2005. 

The modeling was based on 2003 through 2007 design values. Future year modeling for 2012 

and 2018 was conducted and the future year design values were determined without the emission 

reductions associated with CAIR (Round 6), as shown in Table 7.2. The Clean Air Transport 

Rule is expected to provide reductions above and beyond CAIR. 

 

11.0

12.0

13.0

14.0

15.0

16.0

17.0

18.0

00‐04 01‐05 02‐06 03‐07 04‐08 05‐09 06‐10

Concentrations(ug/m3)

Design Value Years

East Chicago Gary ‐ IITRI Gary ‐ Burr St.

Griffith Gary ‐ Madison Street Gary ‐ Ivanhoe

Hammond ‐ Clark HS Dunes Natl. Lakeshore Ogden Dunes

Annual Standard
45

Table 7.2 

LADCO Round 6 Modeling Results 

for Annual PM2.5 – Without CAIR Emission Reductions 

(Using 2003 – 2007 Design Values) 

SITE ID SITE NAME COUNTY 

Design Value 

2003-2007 

(μg/m3) 

Base-case 

2012 

(μg/m3) 

Base-case 

2018 

(μg/m3) 

18-089-0006 East Chicago – Franklin School Lake 14.3 13.7 13.6 

18-089-0027 Griffith Lake 13.8 13.0 12.8 

18-089-1003 Gary – Ivanhoe School Lake 14.0 13.1 12.9 

18-089-2004 Hammond – Purdue Lake 14.1 13.4 13.3 

18-089-2010 Hammond – Clark High School Lake 13.9 13.3 13.2 

18-127-0020 Ogden Dunes Porter 12.7 11.9 11.7 

18-127-0024 Dunes National Lakeshore Porter 13.2 12.4 12.1 

17-031-0022 Chicago – Washington High School Cook - IL 15.2 14.6 14.6 

17-031-0050 Chicago – Southeast Police Station Cook - IL 14.8 14.2 14.1 

17-031-0052 Chicago – Mayfair Pump Station Cook - IL 15.8 14.9 14.7 

17-031-0057 Chicago – Springfield Pump Station Cook - IL 15.0 14.4 14.3 

17-031-0076 Chicago – Com Ed Maintenance Building Cook - IL 14.9 14.3 14.2 

17-031-2001 Blue Island Cook - IL 14.8 14.2 14.1 

17-031-3301 Summit Cook - IL 15.3 14.7 14.6 

17-031-4007 Des Plaines Cook - IL 12.8 12.1 11.8 

17-031-4201 Northbrook Cook - IL 12.8 12.1 11.8 

17-031-6005 Cicero Cook - IL 15.5 14.9 14.8 

17-043-4002 Naperville Du Page - IL 13.8 13.0 12.7 

17-089-0003 Elgin Kane - IL 13.3 12.5 12.1 

17-089-0007 Aurora Kane - IL 14.8 13.9 13.5 

17-097-1007 Zion Lake - IL 11.8 11.2 10.9 

17-111-0001 Cary McHenry - IL 12.4 11.5 11.2 

17-197-1002 Joliet Will - IL 13.7 12.9 12.5 

17-197-1011 Braidwood Will - IL 11.5 10.7 10.5 

Results of the LADCO Round 6 modeling show that the Chicago Area would attain the annual 

NAAQS for fine particles by 2012. As shown in Table 7.2, future year modeled annual fine 

particle concentrations for 2012 will be 4% to 6% lower than baseline annual fine particle design 

values and 5% to 8% lower in 2018 and will continue to decrease thereafter. A graphical 

representation of the results for the fine particle monitors located in Lake and Porter counties, 

Indiana is shown in Graph 7.2.

 
46

Graph 7.2 

LADCO Round 6 Modeling Results for Lake and Porter Counties, Indiana 

for 2012 and 2018 

It should be noted that PM2.5 monitors exist at Gary – IITRI and Gary – Burr Street, however 

these are source oriented monitors used to compare to the daily standard only and are not used to 

determine annual fine particle attainment status. 

7.2 LADCO Round 5 Speciated Modeled Attainment Test Results

The Speciated Modeled Attainment Test (SMAT) is the attainment test for annual fine particles. 

To determine the future year annual fine particle concentrations, speciated data is calculated. 

The different species that were modeled and are associated with fine particles include sulfates, 

nitrates, organic carbon, elemental carbon, ammonium, particle bound water, “other” primary 

inorganic fine particles, and passively collected mass. The SMAT results from LADCO’s Round 

5 modeling are listed below. Round 5 modeled the emission reductions associated with CAIR so 

the results reflect the impacts from CAIR. Percent ranges of the model results from the seven 

active fine particle monitors in Lake and Porter counties, Indiana were broken down into the 

speciated constituents of fine particle emissions. The percent change from the observed 

speciated data in 2005 to the future year modeled results for 2009 are listed in Table 7.3. While 

these modeling results are outdated, this weight of evidence demonstration shows the reduction 

potential from national emission control measures for the PM2.5 species in Northwest Indiana. 

An updated analysis will be conducted at a later time, using more current emissions and 

meteorological data and for a relevant future year projection. 

 

10.0

11.0

12.0

13.0

14.0

15.0

16.0

2003‐2007 2012 2018

Concentrations(ug/m3)

Design Value Years

East Chicago Griffith Gary ‐ Madison St.

Gary ‐ Ivanhoe Hammond ‐ Purdue Hammond ‐ Clark HS

Dunes Natl. Lakeshore Ogden Dunes Annual Standard
47

Table 7.3 

LADCO Round 5 SMAT Modeling Results for Lake and Porter Counties, Indiana 

(Percent decrease from observed to modeled concentrations) 

Species of PM2.5 2009 

Sulfates 9% - 10% 

Nitrates 5% - 6% 

Organic Carbon 1% - 2% 

Elemental Carbon 10% - 20% 

Ammonium 6% - 7% 

Particle Bound Water 9% 

The results demonstrate that elemental carbon, sulfate, particle bound water, ammonium, and 

nitrates concentration decreases are projected to be at least 6% in the future year 2009. Lesser 

organic carbon reductions are projected to occur, up to 2%. LADCO modeling shows good 

performance for sulfates and elemental carbon predicted baseline concentrations, slight overprediction for nitrate concentrations, and under-predictions of organic carbon concentrations. 

Overall, model performance is adequate for SIP planning and gives a good idea of the effects of 

emission reductions from national emission control measures on Lake and Porter counties, 

Indiana. 

7.3 LADCO Round 5 Particulate Source Apportionment Results

Particulate Source Apportionment (PSAT) modeling was conducted by LADCO. The results of 

the PSAT Round 5 modeling show the regional contributions by emission sectors on each 

monitor that was modeled. Chart 7.1 displays the PSAT modeling results for the East Chicago – 

Franklin School, Griffith, Gary – Ivanhoe School, Gary – Clark High School, and Hammond – 

Purdue fine particle monitors in Lake County, Indiana and the Dunes National Lakeshore and 

Ogden Dunes fine particle monitors in Porter County, Indiana. Emission contributions from 

Illinois’ portion of the nonattainment area was the biggest regional contributor to the East 

Chicago – Franklin School, Griffith, Gary – Clark High School, and Hammond – Purdue fine 

particle monitors. Emission contributions from both the Indiana and Illinois portions of the 

nonattainment area were the biggest regional contributors to the Dunes National Lakeshore, 

Ogden Dunes, and Gary – Ivanhoe High School fine particle monitors. Indiana and Illinois were 

the biggest state contributors to all of the monitors depicted in Chart 7.1. 

The PSAT Round 5 modeling results indicate the majority of Indiana’s emission sector 

contributions to fine particle concentrations come from EGUs, ammonium emission sources, 

mobile, and off-road (including marine, aircraft, and railroad), and non-EGU sources. These 

results are considered to be representative of Lake and Porter counties, Indiana as EGU, 

ammonium, and non-EGU emissions impact the entire area. 

 
48

Chart 7.1 

Regional/Emission Sector Particulate Source Apportionment Technology (PSAT) Results 

East Chicago – Franklin School PM2.5 Monitor, Lake County, Indiana 

Griffith PM2.5 Monitor, Lake County, Indiana 
49

Gary – Ivanhoe School PM2.5 Monitor, Lake County, Indiana

Hammond – Purdue PM2.5 Monitor, Lake County, Indiana
50

Gary – Clark High School PM2.5 Monitor, Lake County, Indiana 

Dunes National Lakeshore PM2.5 Monitor, Porter County, Indiana 
51

Ogden Dunes PM2.5 Monitor, Porter County, Indiana 

 

The following pie charts depict the specie contributions to fine particle concentrations at the 

Lake and Porter counties, Indiana monitors. The pie charts include both the observed 2005 

contributions and 2009 modeled contributions for each monitor. Since the monitors are in close 

proximity to each other, results are fairly similar in the distribution of specie concentrations 

among the monitors. Charts 7.2 through 7.7 cover the fine particle monitors in Lake County 

while Charts 7.8 and 7.9 cover the monitors in Porter County with the highest monitored 

concentrations that are used to determine compliance with the annual NAAQS for fine particles. 

The speciation listed in the pie charts include SO4 – sulfate mass, NO3 – nitrate mass, OC – 

organic carbon mass, EC – elemental carbon mass, Soil – crustal material mass, NH4 – 

ammonium mass, PBW – particles bound water mass, and BLAN – passively collected mass. 
52

Chart 7.2 

Modeled Contributions by Specie at the East Chicago – 

Franklin School PM2.5 Monitor 

(Observed Concentrations = 13.8 μg/m3

) (Modeled Concentrations =13.2 μg/m3) 

Chart 7.3 

Modeled Contributions by Specie at the Griffith PM2.5 Monitor 

(Observed Concentrations = 13.3 μg/m3) (Modeled Concentrations =12.4 μg/m3) 

so4

26%

no3

14%

oc

25%

ec

5%

soil

4%

nh4

13%

pbw

10%

blan

4%

Observed 2005 Contributions at the East 

Chicago - Franklin School PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

23%

no3

14%

oc

28%

ec

5%

soil

6%

nh4

12%

pbw

8%

blan

4%

2009 Modeled Contributions at the East 

Chicago - Franklin School PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

27%

no3

14%

oc

24%

ec

4%

soil

4%

nh4

13%

pbw

10%

blan

4%

Observed 2005 Contributions at the 

Griffith PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

24%

no3

15%

oc

27%

ec

4%

soil

5%

nh4

12%

pbw

9%

blan

4%

2009 Modeled Contributions at the 

Griffith PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan
53

Chart 7.4 

Modeled Contributions by Specie at the Gary - Madison Street PM2.5 Monitor 

(Observed Concentrations = 13.5 μg/m3) (Modeled Concentrations =12.3 μg/m3) 

Chart 7.5 

Modeled Contributions by Specie at the Gary - Ivanhoe School PM2.5 Monitor 

(Observed Concentrations = 15.2 μg/m3) (Modeled Concentrations =12.9 μg/m3) 

so4

27%

no3

12%

oc

24%

ec

7%

soil

4%

nh4

12%

pbw

10%

blan

4%

Observed 2005 Contributions at the Gary 

- Madison Street PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

23%

no3

13%

oc

27%

ec

7%

soil

5%

nh4

12%

pbw

9%

blan

4%

2009 Modeled Contributions at the Gary -

Madison Street PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

24%

no3

13%

oc

27%

ec

7%

soil

6%

nh4

11%

pbw

8%

blan

4%

2009 Modeled Contributions at the Gary -

Ivanhoe School PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

27%

no3

12%

oc

24%

ec

7%

soil

4%

nh4

13%

pbw

9%

blan

4%

Observed 2005 Contributions at the Gary 

- Ivanhoe School PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan
54

Chart 7.6 

Modeled Contributions by Specie at the Hammond - Purdue PM2.5 Monitor 

(Observed Concentrations = 13.6 μg/m3) (Modeled Concentrations =12.7 μg/m3) 

Chart 7.7 

Modeled Contributions by Specie at the Hammond – 

Clark High School PM2.5 Monitor 

(Observed Concentrations = 13.4 μg/m3) (Modeled Concentrations =12.5 μg/m3) 

so4

23%

no3

15%

oc

27%

ec

5%

soil

6%

nh4

12%

pbw

8%

blan

4%

2009 Modeled Contributions at the 

Hammond - Purdue PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

26%

no3

14%

oc

24%

ec

5%

soil

4%

nh4

13%

pbw

10%

blan

4%

Observed 2005 Contributions at the 

Hammond - Purdue PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

26%

no3

14%

oc

23%

ec

5%

soil

5%

nh4

13%

pbw

10%

blan

4%

Observed 2005 Contributions at the 

Hammond - Clark High School PM2.5

Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

23%

no3

14%

oc

26%

ec

5%

soil

7%

nh4

12%

pbw

9%

blan

4%

2009 Modeled Contributions at the 

Hammond - Clark High School PM2.5

Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan
55

Chart 7.8 

Modeled Contributions by Specie at the Dunes National 

Lakeshore PM2.5 Monitor 

(Observed Concentrations = 12.1 μg/m3

) (Modeled Concentrations =11.2 μg/m3) 

Chart 7.9 

Modeled Contributions by Specie at the Ogden Dunes PM2.5 Monitor 

(Observed Concentrations = 12.6 μg/m3) (Modeled Concentrations =11.5 μg/m3) 

Results of the Round 5 PSAT modeling for the Lake and Porter counties, Indiana fine particle 

monitors show the highest pollutant contributors to base-case and future year fine particle 

concentrations are sulfate, organic carbon, ammonium, and nitrate. Future year modeling shows 

decreases in sulfates, nitrates, and ammonium. The future year modeling did show slight 

increases in organic carbon and soils from the base-case modeled concentrations. 

so4

26%

no3

14%

oc

23%

ec

5%

soil

5%

nh4

13%

pbw

10%

blan

4%

Observed 2005 Contributions at the 

Dunes National Lakeshore PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

23%

no3

14%

oc

26%

ec

5%

soil

7%

nh4

12%

pbw

9%

blan

4%

2009 Modeled Contributions at the 

Dunes National Lakeshore PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

26%

no3

14%

oc

23%

ec

5%

soil

5%

nh4

13%

pbw

10%

blan

4%

Observed 2005 Contributions at the 

Ogden Dunes PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan

so4

23%

no3

14%

oc

26%

ec

5%

soil

7%

nh4

12%

pbw

9%

blan

4%

2009 Modeled Contributions at the 

Ogden Dunes PM2.5 Monitor

so4

no3

oc

ec

soil

nh4

pbw

blan
56

7.4 Summary of Existing Modeling Results

U.S. EPA and LADCO modeling for future year design values have consistently shown that 

existing national emission control measures will bring Lake and Porter counties, Indiana into 

attainment of the annual NAAQS for fine particles. Emission control measures to be 

implemented in the next several years will provide even greater assurance that air quality will 

continue to meet the standard into the future. Modeling support for CAIR has shown that future 

year design values for Lake and Porter counties, Indiana will continue to attain the annual 

standard for fine particles with modeled future year design values below 15 μg/m3

. U.S. EPA 

future year modeling of national emission control strategies will ensure that Lake and Porter 

counties, Indiana will maintain lower fine particle concentrations with an increasing margin of 

safety. 

7.5 Meteorological Analysis for Lake and Porter Counties, Indiana

Meteorological conditions are one of the most important factors that influence development and 

transport of fine particles. Stagnant surface conditions during any time of the year and upper air 

ridging provides conducive conditions for development and transport of fine particles. 

Ultimately, passage of surface cold fronts with a clean air mass change will lower fine particle 

readings in Lake and Porter counties, Indiana. 

7.6 Surface Air Conditions Present During High Fine Particle Concentration Days

Higher annual concentrations of fine particles tend to correlate with warmer temperatures and 

lighter wind speeds, although high fine particle episodes can occur in the summer or winter. It 

should be noted that higher annual fine particle concentrations are driven by individual days with 

higher fine particle concentrations throughout the monitored year. Therefore, it is difficult to 

attribute higher fine particle concentrations to annualized meteorological rankings. Review of 

several of the higher fine particle concentration episodes over the past few years reveal that 

conditions were hot in the summer with temperatures in the middle 80o

s Fahrenheit or higher and 

average wind speeds were fairly light. Fall and winter days with higher fine particle 

concentrations had near normal temperatures but wind speeds were very light, and humidity was 

higher. 

7.7 Upper Air Conditions Present During High Fine Particle Concentration Days

Upper air ridges and more stagnant surface wind conditions predominately affect development 

and build up of fine particles. Slow moving upper air ridges can effectively suppress mixing 

within the many levels of the atmosphere and cause pollutants to build up over time. Inversions 

or increases in temperature with a rise in altitude will prevent mixing with air from the upper 

atmosphere. These conditions can occur at any time of the year and are evident in elevated fine 

particle episodes in spring, summer, fall, and winter months. Review of surface and upper air 

features of higher fine particle concentration days showed stagnant surface conditions and upper 

air ridges existed on those days and helped in the buildup of fine particle concentrations. 
57

7.8 Analyses of Atmospheric Conditions During High Fine Particle Concentration Days

Analyses have been conducted to determine the atmospheric conditions that are most prevalent 

during higher fine particle concentration days in Indiana. LADCO applied a Classification and 

Regression Tree (CART) analysis to data from Indiana that correlated different levels of fine 

particle concentrations to meteorological conditions from 1999 to 2004 (Donna Kenski, 2005). 

This type of analysis evaluates meteorological conditions, such as temperature, pressure, wind 

speed, wind direction, relative humidity, and dew point temperatures at the surface, as well as 

morning and evening mixing heights in the upper atmosphere which were present when higher 

concentrations of fine particles were monitored. Results of this CART analysis indicated factors 

that played a larger role in higher fine particle concentrations in Indiana were warm-weather 

conditions with high dew points, southwest winds, and high evening mixing heights. Previous 

day’s concentrations of fine particles play a key role in higher impacts as well. 

Fine particles are made up of several constituents, including direct PM2.5, sulfates, nitrates, 

ammonium, organic carbon, and elemental carbon. Depending on the time of the year, 

concentrations of fine particle constituents vary, with nitrates being more prevalent in the winter 

and sulfates more prevalent in the summer. Sulfate and nitrates emission reductions have the 

biggest impact on lower future year fine particle concentrations. 

7.9 Summary of Air Quality Index Days in Lake and Porter Counties, Indiana

An analysis was conducted to review the daily fine particle concentrations over a year to 

determine the Air Quality Index (AQI) trends. Chart 7.10 shows by year (2000 through 2010), 

the percentage of days during the calendar year which fine particle concentrations reached the 

AQI ranges for “Good” (0 to 15.3 μg/m3), “Moderate” (15.4 μg/m3 to 40.4 μg/m3), and 

“Unhealthy for Sensitive Groups (USG)” (40.5 μg/m3 to 65.4 μg/m3). There were no days that 

fine particle levels reached the “Unhealthy” level of 65.5 μg/m3

 to 150.4 μg/m3. 
58

Chart 7.10 

Distribution of PM2.5 Concentration Days on the AQI Levels of Health Concern, 

Lake and Porter Counties, Indiana 

Table 7.4 shows how the years ranked for the three AQI ranges. The year 2009 had the most 

“Good” concentration days during the 11-year period analyzed (2000 through 2010). The year 

2000 had the most “Moderate” concentration days and the years 2001, 2003, and 2005 had the 

most “USG” concentration days with no days recorded in 2006, 2008, and 2009. As can be seen, 

weather plays a large role in fine particle concentration development and transport as 2001, 

2002, 2005, 2007, and 2010 were warmer than normal summers which translated to moderate 

and unhealthy for sensitive group levels of air quality. 

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Percentage of Year

Year

Good Moderate USG
59

Table 7.4 

Ranking and Percentage of Highest Number of Days 

at AQI Levels of Health Concern 

Ranking Good Moderate Unhealthy for 

Sensitive Group 

1st 2009 – 78% 2000 – 46% 2001 – 3%

2nd 2008 – 72% 2001 – 42% 2005 – 3%

3rd 2004 – 69% 2005 – 40% 2003 – 3%

4th 2007 – 69% 2002 – 39% 2000 – 2%

5th 2006 – 66% 2003 – 36% 2010 – 2%

6th 2010 – 64% 2006 – 34% 2002 – 2%

7th 2003 – 63% 2010 – 34% 2007 – 2%

8th 2002 – 60% 2007 – 30% 2004 – 1%

9th 2005 – 59% 2004 – 30%

10th 2001 – 56% 2008 – 28%

11th 2000 – 52% 2009 – 22%

7.10 Summary of Meteorological Analysis for Lake and Porter Counties, Indiana

Annual fine particle concentrations in Lake and Porter counties, Indiana are driven by higher fine 

particle concentration days that can occur during any time of the year. Conditions that are most 

prevalent during higher fine particle concentration days are lighter winds, higher relative 

humidity, and above average temperatures in the summer, and near normal temperatures in the 

fall, winter, or spring. Approximately 70% of the days when PM2.5 concentrations were in the 

USG range occurred in the summer months with maximum high temperatures of 80oF or above. 

Weather plays a large role in fine particle concentration development and transport as 2001, 

2002, 2005, and 2006 were warmer than normal summers which translated to more days of 

moderate and unhealthy for sensitive group levels of air quality. Upper air weather patterns 

generally include ridging over the area with stagnant conditions at the surface caused by lower 

mixing heights and stable conditions for summer episodes and ridging or troughs over the area in 

the fall, winter, or spring episodes. Surface winds from any direction can transport pollutants 

from surrounding areas into Lake and Porter counties, Indiana. Nitrates are bigger contributors 

to fine particle concentrations in the winter and sulfates are bigger contributors to fine particle 

concentrations in the summer. 

8.0 CORRECTIVE ACTIONS 

8.1 Commitment to Revise Plan

As noted in Section 4.6, IDEM commits to review and revise, as appropriate, its Maintenance 

Plan eight years after redesignation, as required by Section 175A of the CAA. 

 
60

8.2 Commitment for Contingency Measures

IDEM will monitor fine particle concentrations to determine whether trends indicate higher 

values or whether emissions appear to be increasing. If it is determined that fine particle levels 

and emissions are increasing and action is necessary to reverse that trend, IDEM will take action 

to reverse the noted trend, prior to a violation of the standard occurring. 

IDEM commits to adopt and expeditiously implement necessary corrective action in accordance 

with an Action Level Response described below. 

Action Level Response

An Action Level Response shall be prompted whenever a violation of the standard (three year 

average annual arithmetic mean value of 15.1 μg/m3

 or greater) occurs. In the event that the 

Action Level is triggered and is not found to be due to an atypical unfavorable meteorological 

condition, exceptional event, malfunction, or noncompliance with a permit condition or rule 

requirement, IDEM will determine additional control measures needed to assure future 

attainment of the annual NAAQS for fine particles. In this case, measures that can be 

implemented in a short time will be selected in order to be in place within eighteen months from 

the end of the year that prompted the Action Level Response. 

Control Measure Selection and Implementation

Adoption of any additional control measures is subject to the necessary administrative and legal 

processes. This process will include publication of notices, an opportunity for public hearing, 

and other measures required by Indiana law for rulemaking by state environmental boards. 

If a new measure or control is already promulgated and scheduled to be implemented at the 

federal or state level, and that measure or control is determined to be sufficient to address the 

upward trend in air quality, additional local measures may be unnecessary. Furthermore, IDEM 

will submit to U.S. EPA an analysis to demonstrate the proposed measures are adequate to return 

the area to attainment. 

8.3 Contingency Measures

Contingency measures to be considered will be selected from a comprehensive list of measures 

deemed appropriate and effective at the time the selection is made. Listed below are example 

measures that may be considered. The selection of measures will be based upon costeffectiveness, emission reduction potential, economic and social considerations, or other factors 

that IDEM deems appropriate. IDEM will solicit input from interested and affected persons in 

the maintenance area prior to selecting appropriate contingency measures. All of the listed 

contingency measures are potentially effective or proven methods of obtaining significant 

reductions of fine particle precursor emissions. Because it is not possible at this time to 

determine what control measure will be appropriate at an unspecified time in the future, the list 

of contingency measures outlined below is not comprehensive. IDEM anticipates that if 
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contingency measures should ever be necessary, it is unlikely that a significant number (i.e., all 

those listed below) will be required. 

1) Vehicle inspection and maintenance program enhancements (increase weight limit, 

addition of diesel vehicles, etc.). 

2) Alternative fuel and diesel retrofit programs for fleet vehicle operations. 

3) Require NOx or SO2 emission offsets for new and modified major sources. 

4) Require NOx or SO2 emission offsets for new and modified minor sources. 

5) Increase the ratio of emission offsets required for new sources. 

6) Require NOx or SO2 controls on new minor sources (less than 100 tons). 

7) Wood stove change out program. 

8) Require increased recovery efficiency at sulfur recovery plants. 

9) Various emission reduction measures or dust suppressant for unpaved roads and/or 

parking lots. 

10) Idling Restrictions. 

11) Broader geographic applicability of existing measures. 

12) One or more transportation control measures sufficient to achieve at least a 0.5% 

reduction in actual area-wide precursor emissions. Transportation measures will be 

selected from the following, based upon the factors listed above, after consultation with 

affected local governments: 

a) Trip reduction programs, including, but not limited to, employer-based 

transportation management plans, area wide rideshare programs, work schedule 

changes, and telecommuting. 

b) Transit improvements. 

c) Traffic flow improvements. 

d) Other new or innovative transportation measures not yet in widespread use that 

affected state and local governments deem appropriate. 

No contingency measure shall be implemented without providing the opportunity for full public 

participation during which the relative costs and benefits of individual measures, at the time they 

are under consideration, can be fully evaluated. 

9.0 PUBLIC PARTICIPATION

Indiana published notification for a public hearing and solicitation for public comment 

concerning the draft Redesignation Petition and Maintenance Plan on the IDEM Web site on 

April 14, 2011, with publication in the following newspapers on the following dates: 

 1) The Indianapolis Star, Indianapolis, Indiana (April 15, 2011). 

2) The Times, Munster, Indiana (April 14, 2011). 

3) The Post Tribune, Merrillville, Indiana (April 14, 2011). 

 
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A public hearing to receive comments concerning the redesignation request was conducted on 

May 18, 2011, at the Lake County Public Library-Highland Branch in Highland, Indiana. The 

public comment period closed on May 20, 2011. One comment letter was received during the 

public comment period. Appendix K includes a copy of the public notice, public hearing script, 

certifications of newspaper publication of the public notice, the official transcript from the public 

hearing, and a detailed summary of and response to substantive comments. 

10.0 CONCLUSIONS 

Lake and Porter counties, Indiana, have attained the annual NAAQS for fine particles. This 

petition demonstrates that Lake and Porter counties, Indiana, have complied with the applicable 

provisions of the CAA regarding redesignation of nonattainment areas for fine particles. IDEM 

has prepared a State Implementation and Maintenance Plan that meets the requirement of Section 

110(a)(1) of the CAA. 

Indiana has performed an analysis that shows the air quality improvements are due to permanent 

and enforceable measures and that additional significant regional NOx and SO2 reductions 

following implementation of the Phase II NOx SIP Call rule, and CAIR or its replacement rule 

will ensure continued compliance (maintenance) with the standard. Furthermore, emission 

projections indicate that NOx and SO2 emissions will continue to decline, ensuring that the area 

continues to maintain compliance with the standard and provide for an increased margin of 

safety. Based on this presentation, Lake and Porter counties, Indiana, meet the requirements for 

redesignation under the CAA (Section 107(d)(3)) and U.S. EPA guidance for fine particles. 

Consistent with the authority granted to U.S. EPA, the State of Indiana requests that Lake and 

Porter counties, Indiana, be redesignated to attainment for the annual fine particles standard 

simultaneously with U.S. EPA approval of this Indiana State Implementation and Maintenance 

Plan.