1

Draft Technical Support Document

Indiana

Area Designations For the 

2010 SO2 Primary National Ambient Air Quality Standard

Summary

Pursuant to section 107(d) of the Clean Air Act, EPA must initially designate areas as either 

“unclassifiable”, “attainment”, or “nonattainment” for the 2010 one-hour sulfur dioxide (SO2) primary 

national ambient air quality standard (NAAQS). The Clean Air Act defines a nonattainment area as 

one that does not meet the NAAQS or that contributes to a violation in a nearby area. 

Indiana submitted recommendations on May 11, 2011 with supplemental recommendations on January 

6, 2012 and April 26, 2012. Table 1 below lists Indiana’s recommendations and identifies the counties 

or portions of counties in Indiana that EPA intends to designate “nonattainment” based on monitored 

violations. 

Table 1. Nonattainment Designation for Indiana

Area Indiana’s Recommended 

Designation of Areas/Counties

EPA’s Intended Designated 

Nonattainment Areas/Counties

Indianapolis, IN

 Marion County (partial)

 -Wayne, Center and Perry Townships

Nonattainment Nonattainment 

Morgan County, IN

 Morgan County (partial)

 -Clay and Washington Townships

Nonattainment Nonattainment 

Richmond, IN

 Wayne County (partial)

 -Wayne Township

Nonattainment Nonattainment 

Southwest Indiana, IN

 Daviess County (partial)

 -Veale Township

 Pike County (partial)

 -Washington Township

Nonattainment

Nonattainment

Nonattainment 

Nonattainment

Terre Haute, IN

 Vigo County (partial)

 -Fayette Township

 -Harrison Township

 -Otter Creek Township

Unclassifiable

Nonattainment

Unclassifiable

Nonattainment 

Nonattainment

Nonattainment
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Background

On June 3, 2010, EPA revised the primary SO2 NAAQS (75 FR 35520, published on June 22, 2010). 

EPA revised the primary SO2 standard by establishing a new one-hour standard at a level of 75 parts 

per billion (ppb) which is attained when the three-year average of the 99th percentile of one-hour daily 

maximum concentrations does not exceed 75 ppb. EPA has determined that this is the level necessary 

to provide protection of public health with an adequate margin of safety, especially for children, the 

elderly and those with asthma. These groups are particularly susceptible to the health effects 

associated with breathing SO2. EPA is revoking the two prior primary standards of 140 ppb evaluated 

over 24 hours, and 30 ppb evaluated over an entire year because they will not add additional public 

health protection given a one-hour standard at 75 ppb. Accordingly, EPA is not designating areas in 

this process on the basis of either of these two primary standards. Similarly, the secondary standard 

for SO2 has not been revised, so EPA is not designating areas in this process on the basis of the 

secondary standard. 

EPA’s SO2 Designation Approach

Section 107(d) of the Clean Air Act requires that not later than one year after promulgation of a new or 

revised NAAQS, state Governors must submit their recommendations for designations and boundaries 

to EPA by June 2011. Section 107(d) also requires EPA to provide notification to states no less than 

120-days prior to promulgating an initial area designation that is a modification of a state’s 

recommendation. EPA was to promulgate initial area designations within two years of promulgation 

of the revised primary standard, although EPA has extended this deadline for one additional year due 

to having insufficient information to promulgate the designations. If a state did not submit designation 

recommendations, EPA will promulgate the designations that it deems appropriate. If a state or tribe 

disagrees with EPA’s intended designations, they have an opportunity to demonstrate why any 

proposed modification is inappropriate.

Designations guidance was issued by EPA through a March 24, 2011, memorandum from Stephen D. 

Page, Director, U.S. EPA, Office of Air Quality Planning and Standards, to Air Division Directors, 

U.S. EPA Regions I-X. This memorandum identifies factors EPA intends to evaluate in determining 

boundaries for areas designated nonattainment. These five factors include: 1) air quality data; 2) 

emissions and emissions-related data (location of sources and potential contribution to ambient SO2

concentrations); 3) meteorology (weather/transport patterns); 4) geography/topography (mountain ranges 

or other air basin boundaries); and 5) jurisdictional boundaries (e.g., counties, air districts, pre-existing 

nonattainment areas, reservations, metropolitan planning organization), among any other criteria deemed to 

be relevant to establishing appropriate area designations and boundaries for the one-hour SO2 NAAQS.

The March 24, 2011, memo recommended that area boundaries default to the county boundary unless 

information provided by the state or tribe justifies a larger or smaller boundary than that of the county. 

EPA believes it is appropriate to evaluate each potential area on a case-by-case basis, and to recognize that 

area-specific analyses conducted by states, tribes and/or EPA may support a differing boundary than a 

county boundary.

In this technical support document, EPA discusses its review and technical analysis of the 

recommendations regarding areas with monitored violations submitted by Indiana for designations for the 

one-hour SO2 standard and any modifications from these recommendations.
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Definition of important terms used in this document:

1) Designated nonattainment area – an area which EPA has determined, based on a state 

recommendation and/or on the technical analysis included in this document, has violated the 2010 SO2

NAAQS, based on the most recent three years of air quality monitoring data, or contributes to a 

violation in a nearby area. 

2) Recommended nonattainment area – an area a state or tribe has recommended that EPA designate

as nonattainment.

3) Violating monitor – an ambient air monitor meeting all methods, quality assurance and siting 

criteria and requirements whose valid design value exceeds 75 ppb, as described in Appendix T of 40 

CFR part 50.

4) 2010 SO2 NAAQS – The NAAQS for SO2 promulgated in 2010. This NAAQS is 75 ppb, based on 

the three year average of the 99th percentile of the annual distribution of daily maximum one-hour 

average concentrations. See 40 CFR Part 50.17.

5) Design Value - a statistic computed according to the data handling procedures of the NAAQS (in 40 

CFR 50 Appendix T) that, by comparison to the level of the NAAQS, indicates whether the area is 

violating the NAAQS.

Technical analysis for the Indianapolis, IN Area

Introduction 

This technical analysis for the Indianapolis, IN Area identifies Marion County with a monitor that 

violates the 2010 SO2 NAAQS, and evaluates nearby counties for contributions to SO2 concentrations 

in the area. EPA has evaluated this county and nearby counties based on a review of the evidence for 

the factors recommended in the March 24, 2011 EPA guidance. 

Figure 1 is a map of the area showing the locations and design values of air quality monitors in the 

area, and the counties surrounding any violating air quality monitors.
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Figure 1. Map of Indianapolis, IN area sources and monitors

For the Indianapolis, IN area, Indiana recommended that a portion of Marion County consisting of 

Center, Perry, and Wayne Townships be designated nonattainment.

Based on EPA's technical analysis described below, EPA agrees with the State’s recommendation. 

Thus, EPA is intending to designate the three recommended townships in Marion County in Indiana as 

nonattainment for the 2010 SO2 NAAQS to define the Indianapolis nonattainment area.

Detailed Assessment

Air Quality Data 

This factor considers the SO2 air quality monitoring data, including the design values (in ppb) 

calculated for all air quality monitors in Marion County in the Indianapolis area and the surrounding 

area based on data for the 2009 to 2011 period.

The 2010 SO2 NAAQS design value for Marion County, Indiana in the Indianapolis, IN area is shown

in Table 2.

Table 2. Air Quality Data for Nonattainment Designations in Indianapolis

County State Recommended

Nonattainment?

Monitor Air Quality 

System ID

Monitor Location SO2 Design Value, 

2009-2011 (ppb)

Marion Yes 18-097-0057 39.749, -86.1836 80

Marion No 18-097-0073 39.7895, -86.0608 56

Marion No 18-097-0078 39.8111, -86.1145 40

Monitor in Bold has the highest 2009-2011 design value in the respective county.
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Marion County shows a monitored violation of the 2010 SO2 NAAQS. Therefore, some area in this

county and possibly additional areas in surrounding counties must be designated nonattainment. The

absence of a violating monitor alone is not a sufficient reason to eliminate nearby counties as 

candidates for nonattainment status. Each area has been evaluated based on the evidence for the five

factors and other relevant information. 

Emissions and Emissions-Related Data

Evidence of SO2 emissions sources in the vicinity of a violating monitor is an important factor for 

determining whether a nearby area is contributing to a monitored violation. For this factor, EPA 

evaluated county level emission data for SO2 and any growth in SO2 emitting activities since the date 

represented by those emissions data.

Emissions 

EPA recognizes that there might be no new information on any changes in emissions that may have 

occurred after 2008, but would consider more recent years if available. Indiana did not provide 

updated emissions information, therefore EPA relied on the 2008 National Emissions Inventory (NEI)

emissions data (NEI08V2). 

Table 3 shows total emissions of SO2 (given in tons per year) for violating and potentially contributing 

counties in and around the Indianapolis area and sources emitting (or anticipated to contribute) greater 

than 100 tons per year of SO2 according to the 2008 NEI. 

Table 3. SO2 Emissions (NEI08V2)

County Facility Located in 

State 

Recommended 

Nonattainment Area?

Facility – Total SO2 Air

Emissions NEI08V2

(tons per year)

Facility Location Total County 

SO2 Emissions 

(tons per year)

Marion, IN Yes IPL Harding Street Station19,57839.7119, -86.1975 26,576

Yes C C Perry K Steam Plant4,493

39.7622, -86.1667

Yes Rolls-Royce Corporation 

Plant 5 & 8- 142

39.7245, -86.2696

Yes Covanta Indianapolis Inc110 

39.7337, -86.1888

Partial Indianapolis Intl- 102 39.7066, -86.321

The four sources that are fully in the nonattainment area recommended by the State are relatively near 

the violating monitor. The Indianapolis International Airport has relatively low emissions and is 

located approximately 13 kilometers from the violating monitor. Thus, while Indiana recommended 

boundaries for administrative convenience that include some but not all of this airport, the exclusion of 

a portion of the airport from the nonattainment does not represent the exclusion of any significant 

contribution to the monitored violation. 
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Emissions Controls

The emissions data used by EPA in this technical analysis and provided in Table 3 represent emissions 

levels taking into account any control strategies implemented on stationary sources in the Indianapolis

area up to and including 2008. EPA has not received any additional information on emissions 

reductions resulting from controls put into place after 2008.

Meteorology (weather/transport patterns)

Indiana provided information indicating that winds on days with high concentrations of SO2 are most 

likely to come from the southwest but occasionally come from the northeast and other directions. 

Geography/topography (mountain ranges or other air basin boundaries)

The Indianapolis area does not have any geographical or topographical barriers significantly limiting 

air-pollution transport within its airshed. Therefore, this factor did not play a significant role in 

determining the nonattainment boundary.

Jurisdictional boundaries 

Indiana did not have any nonattainment areas under the prior SO2 NAAQS. EPA finds that county or 

township boundaries in Indiana provide a suitable administrative basis for formulating nonattainment 

area boundaries. 

Other Relevant Information

EPA did not receive additional information relevant to establishing a nonattainment area boundary for 

this area.

Conclusion

After considering the factors described above, EPA intends to designate, based on monitored 

violations, Wayne, Center and Perry Townships in Marion County as the Indianapolis, IN

nonattainment area for the 2010 SO2 NAAQS. An air quality monitor in Marion County shows a 

violation of the 2010 SO2 NAAQS, based on 2009 to 2011 air quality data. EPA finds these three 

townships include the sources that contribute to this monitored violation. Based on the consideration 

of all the relevant and available information, as described above, EPA believes that the boundaries 

described herein encompass the appropriate nonattainment area.
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Technical analysis for Morgan County, IN

Introduction 

This technical analysis for Morgan County, IN identifies Morgan County with a monitor that violates

the 2010 SO2 NAAQS, and evaluates nearby counties for contributions to SO2 concentrations in the 

area. EPA has evaluated this county and nearby counties based on the evidence for the factors 

recommended in the March 24, 2011 EPA guidance. 

Figure 3 is a map of the area showing the locations and design values of air quality monitors in the 

area, and the counties surrounding any violating air quality monitors.

Figure 3. Map of Morgan County, IN area sources and monitors

For the Morgan County, IN area, Indiana recommended that a portion of Morgan County consisting of 

Clay and Washington Townships be designated nonattainment.

Based on EPA's technical analysis described below, EPA agrees with the State’s recommendation for

the Morgan County nonattainment area, based upon currently available information. These townships 

are listed above in Table 1.

Detailed Assessment

Air Quality Data 
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This factor considers the SO2 air quality monitoring data, including the design values (in ppb) 

calculated for all air quality monitors in Morgan County in the Morgan County area and the 

surrounding area based on data for the 2009 to 2011 period.

The 2010 SO2 NAAQS design values for Morgan County, Indiana in the Morgan County area are 

shown in Table 6.

Table 6. Air Quality Data for Nonattainment Designations in Morgan County

County State Recommended

Nonattainment?

Monitor Air Quality 

System ID

Monitor Location SO2 Design Value, 

2009-2011 (ppb)

Morgan Yes 18-109-1001 39.515, -86.3917 100

Monitors in Bold have the highest 2009 to 2011 design value in the respective county.

Morgan County shows a violation of the 2010 SO2 NAAQS. Therefore, some area in this county and 

possibly additional areas in surrounding counties must be designated nonattainment. The absence of a 

violating monitor alone is not a sufficient reason to eliminate nearby counties as candidates for 

nonattainment status. 

Emissions and Emissions-Related Data

Evidence of SO2 emissions sources in the vicinity of a violating monitor is an important factor for 

determining whether a nearby area is contributing to a monitored violation. For this factor, EPA 

evaluated county level emission data for SO2 and any growth in SO2 emitting activities since the date 

represented by those emissions data.

Emissions 

EPA recognizes that there might be no new information on any changes in emissions that may have 

occurred after 2008, but would consider more recent years if available. Indiana did not provide 

updated emissions information, therefore EPA relied on the 2008 National Emissions Inventory (NEI)

emissions data (NEI08V2). 

Table 7 shows total emissions of SO2 (given in tons per year) for violating and potentially contributing 

counties in and around the Morgan County area and sources emitting (or anticipated to contribute)

greater than 100 tons per year of SO2 according to the 2008 NEI. 

Table 7. SO2 Emissions (NEI08V2)

County Facility Located in 

State 

Recommended 

Nonattainment Area?

Facility – Total SO2 Air

Emissions NEI08V2

(tons per year)

Facility Location Total County 

SO2 Emissions 

(tons per year)

Morgan, IN Yes IPALCO- Pritchard Station13,102

39.4867, -86.4165 13,821

Yes Hydraulic Press Brick Co.-

515

39.538744, -86.370648
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Emissions Controls

The emissions data used by EPA in this technical analysis and provided in Table 7 represent emissions 

levels taking into account any control strategies implemented on stationary sources in the Morgan 

County area up to and including 2008. EPA has not received any additional information on emissions 

reductions resulting from controls put into place after 2008.

Meteorology (weather/transport patterns)

Indiana’s submittal provides pollution rose information that indicates that violations occur most often 

with southwesterly winds, but also indicates that violations can occur with other wind directions as 

well. 

Geography/topography (mountain ranges or other air basin boundaries)

The Morgan County area does not have any geographical or topographical barriers significantly 

limiting air-pollution transport within its airshed. Therefore, this factor did not play a significant role 

in determining the nonattainment boundary.

Jurisdictional boundaries 

Indiana did not have any nonattainment areas under the prior SO2 NAAQS standard. EPA finds that 

county and township boundaries are a suitable administrative basis for defining a nonattainment area.

Other Relevant Information

EPA did not receive additional information relevant to establishing a nonattainment area boundary for 

this area.

Conclusion

After considering the factors described above, EPA intends to designate Clay and Washington 

Townships within Morgan County (as listed in Table 1) to comprise the Morgan County, IN

nonattainment area for the 2010 SO2 NAAQS, based on a monitored violation in the county.

The air quality monitor in Morgan County shows a violation of the 2010 SO2 NAAQS, based on 2009 

to 2011 air quality data. There are no other nearby areas that EPA finds to contribute to the SO2

concentrations in Morgan County. Based on the consideration of all the relevant and available 

information, as described above, EPA believes that the boundaries described herein encompass thean 

appropriate nonattainment area for the 2010 SO2 NAAQS.

Technical analysis for Richmond, IN

Introduction 

This technical analysis for Richmond, IN identifies Wayne County with monitors that violate the 2010 

SO2 NAAQS, and evaluates nearby counties for contributions to SO2 concentrations in the area. EPA 
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has evaluated this county and nearby counties based on the evidence for the factors recommended in 

the March 24, 2011 EPA guidance. 

Figure 4 is a map of the area showing the locations and design values of air quality monitors in the 

area, and the counties surrounding any violating air quality monitors.

Figure 4. Map of Richmond, IN area sources and monitors

For the Richmond, IN area, Indiana recommended that a portion of Wayne County consisting of 

Wayne Township be designated nonattainment. 

Based on EPA's technical analysis described below, EPA agrees with the State’s recommendation for 

the 2010 SO2 NAAQS to comprise the Morgan County nonattainment area, based upon a monitored 

violation of the NAAQS. This nonattainment area is listed above in Table 1.

Detailed Assessment

Air Quality Data 

This factor considers the SO2 air quality monitoring data, including the design values (in ppb) 

calculated for all air quality monitors in Wayne County in the Richmond, IN area and the surrounding 

area based on data for the 2009 to 2011 period.

The 2010 SO2 NAAQS design value for county in the Richmond and surrounding area are shown in 

Table 8.
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Table 8. Air Quality Data for Nonattainment Designations in Richmond

County State Recommended

Nonattainment?

Monitor Air Quality 

System ID

Monitor Location SO2 Design Value, 

2009-2011 (ppb)

Wayne Yes 181770006 39.8122, -84.89 87

Monitors in Bold have the highest 2009 to 2011 design value in the respective county.

Wayne County shows a monitored violation of the 2010 SO2 NAAQS. Therefore, some area in this 

county and possibly additional areas in surrounding counties must be designated nonattainment. The

absence of a violating monitor alone is not a sufficient reason to eliminate nearby counties as 

candidates for nonattainment status. 

Emissions and Emissions-Related Data

Evidence of SO2 emissions sources in the vicinity of a violating monitor is an important factor for 

determining whether a nearby area is contributing to a monitored violation. For this factor, EPA 

evaluated county level emission data for SO2 and any growth in SO2 emitting activities since the date 

represented by those emissions data.

Emissions 

EPA recognizes that there might be no new information on any changes in emissions that may have 

occurred after 2008, but would consider more recent years if available. Indiana did not provide 

updated emissions information, therefore EPA relied on the 2008 National Emissions Inventory (NEI)

emissions data (NEI08V2). 

Table 9 shows total emissions of SO2 (given in tons per year) for violating and potentially contributing 

counties in and around the Richmond area and sources emitting (or anticipated to contribute) greater 

than 100 tons per year of SO2 according to the 2008 NEI. Only Wayne County, shown in bold, 

contains sources sufficiently nearby to consider for including in the Richmond nonattainment area.

Table 9. SO2 Emissions (NEI08V2)

County Facility Located in State 

Recommended 

Nonattainment Area?

Facility – Total SO2 Air

Emissions NEI08V2

(tons per year)

Facility Location Total County SO2

Emissions 

(tons per year)

Wayne, IN Yes Richmond Power & 

Light- 8,681

39.8028, -84.8953 9,012

Emissions Controls

The emissions data used by EPA in this technical analysis and provided in Table 9 represent emissions 

levels taking into account any control strategies implemented on stationary sources in the Richmond

area up to and including 2008. EPA has not received any additional information on emissions 

reductions resulting from controls put into place after 2008.

Meteorology (weather/transport patterns)

Pollution rose information provided by Indiana indicates that violations appear to occur exclusively 

when winds are blowing from the southwest, in which cases the Richmond Power & Light facility is 

upwind of the violating monitor.
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Geography/topography (mountain ranges or other air basin boundaries)

The Richmond area does not have any geographical or topographical barriers significantly limiting airpollution transport within its airshed. Therefore, this factor did not play a significant role in 

determining the nonattainment boundary.

Jurisdictional boundaries 

Indiana did not have any nonattainment areas under the prior SO2 NAAQS standard. EPA finds that 

township and county boundaries provide a suitable administrative basis for defining a nonattainment 

area. 

Other Relevant Information

EPA did not receive additional information relevant to establishing a nonattainment area boundary for 

this area.

Conclusion

After considering the factors described above, EPA intends to designate Wayne Township within 

Wayne County to comprise the Richmond, IN nonattainment area, based on a monitored violation. 

The air quality monitor in Wayne County shows a violation of the 2010 SO2 NAAQS, based on 2009 

to 2011 air quality data. There are no other nearby areas that EPA finds to contribute to the monitored 

violation of the SO2 NAAQS in Wayne County. Based on the consideration of all the relevant and 

available information, as described above, EPA believes that the boundaries described herein 

encompass the appropriate nonattainment area for the 2010 SO2 NAAQS.

Technical analysis for Southwest Indiana, IN

Introduction 

This technical analysis for Southwest Indiana, IN identifies Daviess and Pike Counties with monitors

that violate the 2010 SO2 NAAQS, and evaluates nearby counties for contributions to SO2

concentrations in the area. EPA has evaluated this county and nearby counties based on the evidence 

for the factors recommended in the March 24, 2011 EPA guidance.

Figure 5 is a map of the area analyzed showing the locations and design values of air quality monitors 

in the area, and the counties surrounding any violating air quality monitors.
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Figure 5. Map of Southwest Indiana area sources and monitors

For the Southwest Indiana, IN area, Indiana recommended that Veale Township within Daviess 

County and Washington Township within Pike County be designated nonattainment. 

Based on EPA's technical analysis described below, EPA agrees with the State’s recommendation for 

the boundaries of the Morgan County nonattainment area for the 2010 SO2 NAAQS. The townships to 

be included in the nonattainment area are listed above in Table 1.

Detailed Assessment

Air Quality Data 

This factor considers the SO2 air quality monitoring data, including the design values (in ppb) 

calculated for all air quality monitors in Daviess and Pike counties in the Southwest Indiana area and 

the surrounding area based on data for the 2009 to 2011 period.

The 2010 SO2 NAAQS design values for Daviess and Pike Counties, Indiana in the Southwest Indiana

area are shown in Table 10.

Table 10. Air Quality Data for Nonattainment Designations in Southwest Indiana

County State Recommended

Nonattainment?

Monitor Air Quality 

System ID

Monitor Location SO2 Design Value, 

2009-2011 (ppb)

Daviess Yes 180270002 38.5728, -87.2147 118

Pike Yes 181250005 38.5192, -87.2497 175

Monitors in Bold have the highest 2009 to 2011 design value in the respective county.
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Daviess and Pike Counties show monitored violations of the 2010 SO2 NAAQS. Therefore, some area 

in these counties and possibly additional areas in surrounding counties must be designated 

nonattainment. The absence of a violating monitor alone is not a sufficient reason to eliminate nearby 

counties as candidates for nonattainment status. 

Emissions and Emissions-Related Data

Evidence of SO2 emissions sources in the vicinity of a violating monitor is an important factor for 

determining whether a nearby area is contributing to a monitored violation. For this factor, EPA 

evaluated county level emission data for SO2 and any growth in SO2 emitting activities since the date 

represented by those emissions data.

Emissions 

EPA recognizes that there might be no new information on any changes in emissions that may have 

occurred after 2008, but would consider more recent years if available. Indiana did not provide 

updated emissions information, therefore EPA relied on the 2008 National Emissions Inventory (NEI)

emissions data (NEI08V2). 

Table 11 shows total emissions of SO2 (given in tons per year) for violating and potentially 

contributing counties in and around the Southwest Indiana area and sources emitting (or anticipated to 

contribute) greater than 100 tons per year of SO2 according to the 2008 NEI. The counties that 

contain all or part of the Southwest Indiana nonattainment area for the 2010 SO2 NAAQS are shown in 

bold. 

Table 11. SO2 Emissions (NEI08V2)

County Facility Located in State 

Recommended 

Nonattainment Area?

Facility – Total SO2 Air 

Emissions NEI08V2

(tons per year)

Facility Location Total County 

SO2 Emissions 

(tons per year)

Pike Yes Hoosier Energy - Ratts 

Station- 27,334

38.5183, -87.2722 49,850

Yes IPL Petersburg Generating 

Station - 22,494

38.5267, -87.2525

Daviess None 150

Emissions Controls

The emissions data used by EPA in this technical analysis and provided in Table 11 represent 

emissions levels taking into account any control strategies implemented on stationary sources in the 

Southwest Indiana area up to and including 2008. EPA has not received any additional information on 

emissions reductions resulting from controls put into place after 2008.

Meteorology (weather/transport patterns)

Pollution rose information provided by Indiana suggests that high concentrations of SO2 at the Pike 

County monitor are most likely to occur with winds ranging from southwesterly to northwesterly. 

Nevertheless, when considering a one hour standard, violations can occur at anytime, even when 

weather patterns are varied from the normal trends of the area. For this area, wind patterns can be from 

any direction. Therefore, for a one hour standard, it is useful to consider all directions to have 

potential contribution.
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Geography/topography (mountain ranges or other air basin boundaries)

The Southwest Indiana area does not have any geographical or topographical barriers significantly 

limiting air-pollution transport within its airshed. Therefore, this factor did not play a significant role 

in determining the nonattainment boundary.

Jurisdictional boundaries 

Indiana did not have any nonattainment areas under the prior SO2 NAAQS standard. EPA finds that 

township and county boundaries provide a suitable administrative basis for defining a nonattainment 

area. 

Other Relevant Information

EPA did not receive additional information relevant to establishing a nonattainment area boundary for 

this area.

Conclusion

After considering the factors described above, EPA intends to designate Veale Township within 

Daviess County and Washington Township within Pike County as the Southwest Indiana, IN

nonattainment area for the 2010 SO2 NAAQS. 

The air quality monitors in Daviess and Pike Counties shows violations of the 2010 SO2 NAAQS, 

based on 2009 to 2011 air quality data. There are no nearby areas outside these counties that EPA 

finds to contribute to the SO2 NAAQS violations in Daviess and Pike Counties. Based on the 

consideration of all the relevant and available information, as described above, EPA believes that the 

boundaries described herein encompass the appropriate nonattainment area for the 2010 SO2 NAAQS.

Technical analysis for Terre Haute, IN

Introduction 

This technical analysis for Terre Haute, IN identifies Vigo County with monitors that violate the 2010 

SO2 NAAQS and evaluates nearby counties for contributions to SO2 concentrations in the area. EPA 

has evaluated this county and nearby counties based on the evidence for the factors recommended in 

the March 24, 2011 EPA guidance.

Figure 6 is a map of the area showing the locations and design values of air quality monitors in the 

area, and the counties surrounding any violating air quality monitors.
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Figure 6. Map of Terre Haute, IN area sources and monitors

For the Terre Haute, IN area, Indiana recommended that a portion of Vigo County consisting of 

Harrison Township be designated nonattainment.

However, EPA intends in addition to include Fayette Township and Otter Creek Township in this 

nonattainment area, to include an important contributing source (PSI Energy’s Wabash River plant, in 

Fayette Township) and connecting land to provide a continuous nonattainment area (in Otter Creek 

Township). Based on EPA's technical analysis described below, EPA is intending to designate these 

townships in Vigo County in Indiana as nonattainment for the 2010 SO2 NAAQS as part of the Terre 

Haute nonattainment area, based upon currently available information. These townships are listed 

above in Table 1.

Detailed Assessment

Air Quality Data 

This factor considers the SO2 air quality monitoring data, including the design values (in ppb) 

calculated for all air quality monitors in Vigo County in the Terre Haute, IN Area and the surrounding 

area based on data for the 2009 to 2011 period.

The 2010 SO2 NAAQS design values for county in the Terre Haute area is shown in Table 12.
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Table 12. Air Quality Data for Nonattainment Designations in Indiana

County State Recommended

Nonattainment?

Monitor Air Quality 

System ID

Monitor Location SO2 Design Value, 

2009-2011 (ppb)

Vigo, IN Yes 181671014 39.5147, -87.4078 150

Yes 181670018 39.4861, -87.4014 90

Monitors in Bold have the highest 2009-2011 design value in the respective county.

Vigo County shows monitored violations of the 2010 SO2 NAAQS. Therefore, some area in this 

county and possibly additional areas in surrounding counties must be designated nonattainment. The

absence of a violating monitor alone is not a sufficient reason to eliminate nearby counties as 

candidates for nonattainment status. 

Emissions and Emissions-Related Data

Evidence of SO2 emissions sources in the vicinity of a violating monitor is an important factor for 

determining whether a nearby area is contributing to a monitored violation. For this factor, EPA 

evaluated county level emission data for SO2 and any growth in SO2 emitting activities since the date 

represented by those emissions data.

Emissions 

EPA recognizes that there might be no new information on any changes in emissions that may have 

occurred after 2008, but would consider more recent years if available. Indiana did not provide 

updated emissions information, therefore EPA relied on the 2008 National Emissions Inventory (NEI)

emissions data (NEI08V2). 

Table 13 shows total emissions of SO2 (given in tons per year) for violating and potentially 

contributing counties in and around the Terre Haute Area and sources emitting or anticipated to 

contribute greater than 100 tons per year of SO2 according to the 2008 NEI. The counties that contain 

all or part of the Terre Haute nonattainment area for the 2010 SO2 NAAQS are shown in bold. 

Table 13. SO2 Emissions NEI08V2

County Facility Located 

in State 

Recommended 

NA Area?

Facility – Total SO2 Air

Emissions NEI08V2

(tons per year)

Facility Location Total County 

SO2 Emissions 

(tons per year)

Vigo, IN No* PSI Energy - Wabash River75,823

39.53, -87.4247 78,291

Yes International Paper Co- 1,215 39.4408, -87.42295

No* Wabash River Combined

Cycle Plant- 414

39.530785, -87.424787

No Danisco Sweeteners- 370 39.361448, -87.413742

*These sources are included in the nonattainment area that EPA intends to promulgate

The most significant source in the area, the PSI Energy – Wabash River facility, is located in Fayette 

Township, just northwest of Harrison Township. This facility clearly contributes to the violation in 

Vigo County and must be included in the nonattainment area.
18

Emissions Controls

The emissions data used by EPA in this technical analysis and provided in Table 13 represent 

emissions levels taking into account any control strategies implemented on stationary sources in the 

Terre Haute area up to and including 2008. EPA has not received any additional information on 

emissions reductions resulting from controls put into place after 2008.

Meteorology (weather/transport patterns)

Pollution rose information provided by Indiana indicates that high concentrations of SO2 are especially 

likely to occur with winds from the northwest (when winds are blowing from the PSI Energy-Wabash 

River facility toward the violating monitors), but high concentrations can occur with a range of other 

wind directions as well.

Geography/topography (mountain ranges or other air basin boundaries)

The Terre Haute Area does not have any geographical or topographical barriers significantly limiting 

air-pollution transport within its airshed. Therefore, this factor did not play a significant role in 

determining the nonattainment boundary.

Jurisdictional boundaries 

Indiana did not have any nonattainment areas under the prior SO2 NAAQS standard. EPA finds that 

township and county boundaries provide a suitable administrative basis for defining a nonattainment 

area.

Conclusion

Two air quality monitors in Vigo County show a violation of the 2010 SO2 NAAQS, based on 2009 to 

2011 air quality data. Indiana recommended defining a nonattainment area to include only Harrison 

Township, which includes the two monitors recording violations of the standard. EPA finds that the 

nonattainment area must also include PSI Energy’s Wabash River power plant, which EPA finds to be 

a key contributor to the violations. This plant is located nearby in Fayette Township. EPA also 

intends to define a single relatively continuous area, which EPA envisions achieving by also including 

Otter Creek Township as a connecting township. Thus, after considering the factors described above, 

EPA intends to designate the Terre Haute, IN Area as nonattainment for the 2010 SO2 NAAQS and to 

define this area to include Harrison, Otter Creek, and Fayette Townships in Vigo County.