1

Kentucky

Area Designations for the

2008 Ozone National Ambient Air Quality Standards

The table below identifies the areas and associated counties or parts of counties in Kentucky that EPA 

intends to designate as nonattainment for the 2008 ozone national ambient air quality standards (2008 

ozone NAAQS). In accordance with section 107(d) of the Clean Air Act, EPA must designate an area 

(county or part of a county) “nonattainment” if it is violating the 2008 ozone NAAQS or if it is 

contributing to a violation of the 2008 ozone NAAQS in a nearby area. The technical analyses 

supporting the boundaries for the individual nonattainment areas are provided below.

Table 1. Intended Nonattainment Areas in Kentucky

Area 

Kentucky’s Recommended 

Nonattainment Counties

EPA’s Intended Nonattainment 

Counties

Cincinnati-MiddletownWilmington, OH-KY-IN*

None Boone 

Campbell

Kenton

* Cincinnati-Middletown-Wilmington, OH-KY-IN is a multi-state nonattainment area. Table 2 below 

identifies the counties in the other states that EPA intends to designate as part of the nonattainment area.

EPA intends to designate the remaining counties in Kentucky that are not listed in the table above as 

“unclassifiable/attainment” for the 2008 ozone NAAQS. 

The analysis below provides the basis for intended nonattainment area boundaries. It relies on our 

analysis of whether and which monitors are violating the 2008 ozone NAAQS, based on certified air 

quality monitoring data from 2008-2010 and an evaluation of whether nearby areas are contributing to 

such violations. EPA issued guidance on December 4, 2008 that identified these factors as ones EPA

would consider in determining nonattainment area boundaries and recommended that states consider 

these factors in making their designations recommendations to EPA.1 

1. Air quality data (including the design value calculated for each Federal Reference Method or 

Federal Equivalent Method (FEM) monitors in the area);

2. Emissions and emissions-related data (including location of sources and population, amount of 

emissions and emissions controls, and urban growth patterns);

3. Meteorology (weather/transport patterns);

4. Geography and topography (mountain ranges or other basin boundaries);

5. Jurisdictional boundaries (e.g., counties, air districts, existing nonattainment areas, Indian 

country, metropolitan planning organizations (MPOs))

Ground-level ozone generally is not emitted directly into the air, but is created by chemical reactions 

between oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight. 

Because NOx and VOC emissions from a broad range of sources over a wide area typically contribute to 

 

1 The December 4, 2008 guidance memorandum “Area Designations for the 2008 Revised Ozone National Ambient Air 

Quality Standards” refers to 9 factors. In this technical support document we have grouped the emissions-related factors 

together under the heading of “Emissions and Emissions-Related Data,” which results in 5 categories of factors.
2

violations of the ozone standards, EPA believes it is important to consider whether there are contributing 

emissions from a broad geographic area. Accordingly, EPA chose to examine the 5 factors with respect 

to the larger of the Combined Statistical Area (CSA) or Core Based Statistical Area (CBSA) associated 

with the violating monitor(s).

2 All data and information used by EPA in this evaluation are the latest 

available to EPA and/or provided to EPA by states or tribes.

In EPA’s designations guidance for the 2008 ozone NAAQS3EPA recommended examining 

CSA/CBSAs because certain factors used to establish CSAs and CBSAs are similar to the factors EPA is 

using in this technical analysis to determine if a nearby area is contributing to a violation of the 2008 

ozone NAAQS. Congress required a similar approach in 1990 for areas classified as serious or above 

for the 1-hour ozone standard and EPA used the same basic approach in the designation process for the 

1997 ozone NAAQS. Where a violating monitor is not located in a CSA or CBSA, EPA’s guidance 

recommended using the boundary of the county containing the violating monitor as the starting point for 

considering the nonattainment area’s boundary. 

Technical Analysis for Cincinnati-Middletown-Wilmington, OH-KY-IN 

Figure 1 is a map of the Cincinnati-Middletown-Wilmington, OH-KY-IN intended nonattainment area. 

The map provides other relevant information including the locations and design values of air quality 

monitors, county and other jurisdictional boundaries, existing maintenance boundary for the 1997 ozone 

NAAQS, Cincinnati-Middletown-Wilmington, OH-KY-IN CSA boundary, and major transportation 

arteries.

 

2 Lists of CBSAs and CSAs and their geographic components are provided at 

www.census.gov/population/www/metroareas/metrodef.html . The lists are periodically updated by the Office of 

Management and Budget. EPA used the most recent update, based on 2008 population estimates, issued on December 1, 

2009 (OMB Bulletin No. 10-02).
3

Figure 1. Cincinnati-Middletown-Wilmington, OH-KY-IN Area

For purposes of the 1997 8-hour ozone NAAQS, this Area was designated nonattainment. The 

boundary for the nonattainment area for the 1997 ozone NAAQS included Boone, Campbell and Kenton 

Counties, in their entireties, in Kentucky; Butler, Clermont, Clinton, Hamilton and Warren Counties, in 

their entireties, in Ohio; and a portion of Dearborn County(Lawrenceburg Township) in Indiana. 

In March 2009, Kentucky recommended that Kenton County be designated as “nonattainment” for the 

2008 8-hour ozone standard based on air quality data from 2006-2008. In October 2011, Kentucky

submitted an update to their 2009 recommendation and revised their recommendation to “attainment” 

designations for each county in the State. Letters from Leonard K, Peters, Kentucky Energy and 

Environmental Cabinet Secretary to A. Stanley Meiburg, Acting Administrator, US EPA Region 4

(March 12, 2009) and Gwendolyn Keyes Fleming, Regional Administrator US EPA Region 4 (October 

13, 2011) (on file with US EPA Region 4). 

Additionally, in March 2009, Ohio recommended that Butler, Clermont, Clinton, Hamilton, and Warren

Counties in Ohio be designated as “nonattainment” for the 2008 8-hour ozone standard based on air 

quality data from 2006-2008. Ohio did not send an updated recommendation in 2011. Letter from Chris 
4

Korleski, State of Ohio Environmental Protection Agency Director to Lynn Buhl, Regional 

Administrator, US EPA Region 5 (March 9, 2009) (on file with US EPA Region 5). 

Indiana, in March 2009, recommended that each county in Indiana be designated as “attainment. 

Indiana did not send in updated recommendations in 2011 Letter from Thomas W. Easterly, Indiana 

Department of Environmental Management Commissioner to Bharat Mathur, Acting Regional 

Administrator US EPA Region 5 (March 11, 2009) (on file with US EPA Region 4). These data are 

from FEM monitors sited and operated in accordance with 40 CFR Part 58. 

After considering these recommendations and based on EPA's technical analysis described below, EPA 

intends to designate three whole counties in Kentucky; five whole counties in Ohio; and a partial county 

in Indiana (identified in Table 2 below) as “nonattainment” for the 2008 ozone NAAQS as part of the 

Cincinnati-Middletown-Wilmington nonattainment area. 

Table 2. State's Recommended and EPA’s Intended Designated Nonattainment Counties for CincinnatiMiddletown-Wilmington, OH-KY-IN 

CincinnatiMiddletownWilmington, OH-KYIN

State-Recommended 

Nonattainment Counties

EPA Intended

Nonattainment Counties

Indiana None Dearborn (partial)

Kentucky None Boone

Campbell

Kenton

Ohio Butler

Clermont

Clinton

Hamilton

Warren

Butler

Clermont

Clinton

Hamilton

Warren

Factor Assessment

Factor 1: Air Quality Data 

For this factor, we considered 8-hour ozone design values (in parts per billion (ppb)) for air quality 

monitors in counties in the Cincinnati-Middletown-Wilmington, OH-KY-IN Area based on data for the 

2008-2010 period (i.e., the 2010 design value, or DV), which are the most recent years with fullycertified air quality data. A monitor’s DV is the metric or statistic that indicates whether that monitor 

attains a specified air quality standard. The 2008 ozone NAAQS are met at a monitor when the annual 

fourth-highest daily maximum 8-hour average concentration, averaged over 3 years is 75 ppb or less. A 

DV is only valid if minimum data completeness criteria are met. See 40 CFR part 50 Appendix P. 

Where several monitors are located in a county (or a designated nonattainment area or maintenance 

area), the DV for the county or area is determined by the monitor with the highest individual design 

value.
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Note: Monitors that are eligible for providing design value data generally include State and Local Air 

Monitoring Stations (SLAMS) that are sited in accordance with 40 CFR Part 58, Appendix D (Section 

4.1) and operating with a federal reference method (FRM) or federal equivalent method (FEM) monitor 

that meets the requirements of 40 CFR part 58, appendix A. All data from a special purpose monitor 

(SPM) using an FRM or FEM which has operated for more than 24 months is eligible for comparison to 

the NAAQS unless the monitoring agency demonstrates that the data came from a particular period 

during which the requirements of appendix A (quality assurance requirements) or appendix E (probe and 

monitoring path siting criteria) were not met.

The 2010 DVs for the ozone NAAQS for counties in the Cincinnati-Middletown-Wilmington, OH-KYIN and nearby surrounding area are shown in Table 3. 

Table 3. Ozone Air Quality Data for the Cincinnati-Middletown-Wilmington, OH-KY-IN CSA

County

State 

Recommended 

Nonattainment?

2010 8-hour Ozone 

DV (ppb)

Boone, KY No 65

Butler, OH Yes 78

Campbell, KY No 72

Clermont, OH Yes 71

Clinton, OH Yes 74

Hamilton, OH Yes 79

Warren, OH Yes 78

Hamilton, Butler, and Warren Counties in Ohio show a violation of the 2008 ozone NAAQS, therefore 

these counties are included in the nonattainment area. A county (or partial county) must also be 

designated nonattainment if it contributes to a violation in a nearby area. Each county without a 

violating monitor that is located near a county with a violating monitor has been evaluated based on the 

weight of evidence of the five factors and other relevant information to determine whether it contributes 

to the nearby violation. 

Factor 2: Emissions and Emissions-Related Data

EPA evaluated emissions of ozone precursors (NOx and VOC) and other emissions-related data that 

provide information on areas contributing to violating monitors.

Emissions Data

EPA evaluated county-level emission data for NOx and VOC derived from the 2008 National Emissions 

Inventory (NEI), version 1.5. This is the most recently available NEI. (See 

http://www.epa.gov/ttn/chief/net/2008inventory.html). Significant emissions levels in a nearby area 

indicate the potential for the area to contribute to observed violations. We will also consider any 

additional information we receive on changes to emissions levels that are not reflected in recent 

inventories. These changes include emissions reductions due to permanent and enforceable emissions 

controls that will be in place before final designations are issued and emissions increases due to new 

sources. The precursor emission source-category percentages used below and throughout the document 

were derived from emissions data from the 2008 NEI version 1.5 referenced above.
6

Table 4. Total 2008 VOC and NOx Emissions (tons/year) in the Cincinnati-Middletown-Wilmington, 

OH-KY-IN CSA

State/County State Recommended 

Nonattainment?

VOC Emissions

(tpy)

NOx Emissions

(tpy)

Indiana:

Dearborn No 3,572 11,637

Franklin No 1,097 862

Ohio No 210 259

Kentucky:

Boone No 4,332 8,848

Bracken No 361 760

Campbell No 2,260 2,697

Gallatin No 671 1,634

Grant No 1,148 1,623

Kenton No 3,901 4,095

Pendleton No 608 1,394

Ohio:

Brown No 1,720 1,430

Butler Yes 10,813 12,600

Clermont Yes 5,809 28,461

Clinton Yes 2,618 2,941

Hamilton Yes 26,816 38,664

Warren Yes 5,618 6,027

CSA Total 71,554 123,933

*Counties that EPA intends to designate as nonattainment are shown in bold.

Indiana:

From the emissions data in Table 4, it can be seen that, for Indiana, relatively high 2008 VOC and NOx 

emissions in the vicinity of the violating counties originate in Dearborn County. Emissions from these 

counties in 2008 account for 5.0 percent of the VOC emissions and 9.4 percent of the NOx emissions for 

the entire Cincinnati-Middletown-Wilmington, OH-KY-IN CSA. The majority of these emissions come 

from the American Electric Power (AEP) - Tanner’s Creek Generating Station located in the Lawrence 

Township adjacent to the recommended nonattainment area. 

The VOC and NOx emissions from Franklin and Ohio Counties in Indiana are considerably smaller than 

those originating in the higher emitting counties elsewhere in the Cincinnati-Middletown-Wilmington, 

OH-KY-IN CSA. This would support the exclusion of these counties from the recommended ozone 

nonattainment area for the 2008 8-hour ozone NAAQS.

Kentucky:

Based on the 2008 NEI, 62 percent of Boone County’s NOx emissions are from point sources, and 21 

percent of Boone County’s NOx emissions from mobile sources. Less than 5 percent of Campbell 

County’s NOx emissions are from point sources and 57 percent of Campbell County’s NOX emissions 

are from mobile sources. Kenton County also has less than 5 percent of its NOx emission from point 

sources but 63 percent of Kenton County’s NOX emissions are from mobile sources. Boone County has 
7

29 percent of its VOC emission coming from area sources and 23 percent of its VOC emissions from 

mobile sources. Campbell County has 35 percent of its VOC emissions coming from area sources and 

43 percent of VOC emissions from mobile sources. Kenton County has 38 percent of its VOC emission 

coming from area sources and 41 percent of its VOC emissions from mobile sources. 

The VOC and NOx emissions from Bracken, Gallatin, Grant, and Pendleton Counties, Kentucky are 

considerably less than those originating in the higher emitting counties elsewhere in the CincinnatiMiddletown-Wilmington, OH-KY-IN CSA. This would support the exclusion of these counties from 

the recommended ozone nonattainment area for the 2008 8-hour ozone NAAQS.

Ohio:

From the emissions data in Table 4, it can be seen that, for Ohio, relatively high 2008 VOC and NOx 

emissions in the vicinity of the violating counties originate in the following counties: Butler, Clermont, 

Hamilton, and Warren. Emissions from these counties in 2008 account for 68.6 percent of the VOC 

emissions and 69.2 percent of the NOx emissions for the entire Cincinnati-Middletown-Wilmington, 

OH-KY-IN CSA. 

The VOC and NOx emissions from Brown County, Ohio are smaller than those originating in the higher 

emitting counties elsewhere in the Cincinnati-Middletown-Wilmington, OH-KY-IN CSA. This would 

support the exclusion of this county from the recommended ozone nonattainment area for the 2008 8-

hour ozone NAAQS.

Population density and degree of urbanization

EPA evaluated the population and vehicle use characteristics and trends of the Area as indicators of the 

probable location and magnitude of non-point source emissions. These include ozone-creating 

emissions from on-road and off-road vehicles and engines, consumer products, residential fuel 

combustion, and consumer services. Areas of dense population or commercial development are an 

indicator of area source and mobile source NOx and VOC emissions that may contribute to violating 

ozone monitors. Rapid population or vehicle miles travelled (VMT) growth (see below) in a county on 

the urban perimeter signifies increasing integration with the core urban area, and indicates that it may be 

appropriate to include the Area associated with the area source and mobile source emissions as part of

the nonattainment area. Table 5 shows the population, population density, and population growth 

information for each county in the Cincinnati-Middletown-Wilmington, OH-KY-IN CSA.

Table 5. Population and Population Growth In the Cincinnati-Middletown-Wilmington, OH-KY-IN 

CSA

State/County State 

Recommended 

Nonattainment

2010 

Population

2010 

Population 

Density

(1,000 per 

square mile)

Change in 

Population 

(2000-2010)

Population 

Percent 

Change

(2000-2010)

Indiana:

Dearborn No 50,047 0.16 3,702 8

Franklin No 23,087 0.06 866 4

Ohio No 6,128 0.07 492 9

Kentucky:
8

Boone No 118,811 0.46 31,811 37

Bracken No 8,488 0.04 211 3

Campbell No 90,336 0.57 1,680 2

Gallatin No 8,589 0.08 705 9

Grant No 24,662 0.09 2,115 9

Kenton No 159,720 0.97 8,032 5

Pendleton No 14,877 0.05 389 3

Ohio:

Brown No 44,846 0.09 2,263 5

Butler Yes 368,130 0.78 34,447 10

Clermont Yes 197,363 0.43 18,733 10

Clinton Yes 42,040 0.10 1,378 3

Hamilton Yes 802,374 1.94 -41,916 -5

Warren Yes 212,693 0.52 52,006 32

Area-wide 2,172,191 0.45 116,914 6

*Counties that EPA intends to designate as nonattainment are shown in bold.

Sources: U.S. Census Bureau population estimates for 2010 as of August 4, 2011 

(http://factfinder2.census.gov/faces/tableservices/jsf/pages/productview.xhtml?pid=DEC_10_PL_GCTP

L2.STO5&prodType=table)

Indiana: 

For Indiana, the population data shows that the populations are smaller than the counties in Ohio and the 

larger counties in Kentucky, but Dearborn County is showing a moderate population implying moderate 

population-related VOC and NOx emissions. In addition, the population change rate in Dearborn 

County exceeds the population change rate for the entire Cincinnati-Middletown-Wilmington, OH-KYIN area, implying that the population-related emission contribution from this county is increasing 

relative to those from other counties in the Cincinnati-Middletown-Wilmington, OH-KY-IN area. Ohio 

County, Indiana population change rate increased from 2000-2011, however, the county’s 2010 

population is low compared to the CSA total population.

Kentucky:

For Kentucky, Boone, Campbell, and Kenton have relatively high populations and population densities

when compared to the rest of the CSA. Bracken, Gallatin, Grant and Pendleton are smaller when 

compared to the counties included in the non-attainment recommendation. Boone County at 37 percent 

and Warren County at 32 percent had the highest percentage of population growth for any of the 

counties in the listed as part of the Cincinnati-Middletown-Wilmington CSA. Other counties in this 

CSA did not have as large of a population percentage change with the growth rates ranging from a 2 to 

10 percent increase. Hamilton County population decreased by 5 percent from 2000-2010.

Ohio:

For Ohio, the population data show that Butler, Clermont, Hamilton, and Warren Counties have 

relatively high populations and population densities. This implies that the population-related VOC and 

NOx emissions in these counties are relatively high. In addition, the population change rates in Butler, 

Clermont, and Warren Counties exceed the population change rate for the entire CincinnatiMiddletown-Wilmington, OH-KY-IN area, implying that the population-related emission contributions 
9

from these counties are increasing relative to those from other counties in the Cincinnati-MiddletownWilmington, OH-KY-IN area.

Traffic VMT data and commuting patterns

EPA evaluated the total VMT for each county in the Area. In combination with the 

population/population density data and the location of main transportation arteries (see above), this 

information helps identify the probable location of non-point source emissions. A county with high 

VMT is generally an integral part of an urban area and indicates the presence of motor vehicle emissions 

that may contribute to ozone formation that contributes to nonattainment in the area. Rapid population or 

VMT growth in a county on the urban perimeter signifies increasing integration with the core urban 

area, and indicates that the associated area source and mobile source emissions may be appropriate to 

include in the nonattainment area. Table 6 includes the total 2008 VMT along with state 

recommendations.

Table 6. Traffic VMT Data.

County

State 

Recommended 

Nonattainment?

2008 VMT 

(million 

miles)

Indiana

Dearborn, IN Yes

 

904 

Franklin, IN No

 

316 

Ohio, IN No

 

63 

Kentucky

Boone, KY No

 

1,095 

Bracken, KY No

 

89 

Campbell, KY No

 

1,005 

Gallatin, KY No

 

278 

Grant, KY No

 

432 

Kenton, KY No

 

1,669 

Pendleton, KY No

 

182 

Ohio

Brown, OH No

 

413 

Butler, OH Yes

 

2,469 

Clermont, OH Yes 
10

1,464 

Clinton, OH Yes

 

655 

Hamilton, OH Yes

 

7,391 

Warren, OH Yes

 

1,640 

Areawide:

 

20,063 

*Counties that EPA intends to designate as nonattainment are shown in bold.

* MOBILE model VMTs are those inputs into the NEI version 1.5. 

For Indiana, the VMT data show that VMT levels in Dearborn County are a significant portion of the 

total VMT for the Cincinnati-Middletown-Wilmington, OH-KY-IN CSA.

For Kentucky, the VMT data show that VMT levels in Boone, Campbell, and Kenton Counties are 

larger than those in Bracken, Gallatin, Grant, and Pendleton Counties and, accumulatively, are a large

portion of the total VMT for the Cincinnati-Middletown-Wilmington, OH-KY-IN CSA.

For Ohio, the VMT data show that VMT levels in Butler, Clermont, Hamilton, and Warren Counties are 

higher than those in Brown and Clinton Counties and, accumulatively, are a large portion of the total 

VMT for the Cincinnati-Middletown-Wilmington, OH-KY-IN CSA.

Factor 3: Meteorology (weather/transport patterns)

For this factor, EPA analyzed 30-years of National Weather Service (NWS) wind speed and wind 

direction data collected at the Covington/Greater Cincinnati Airport (NWS Station 93814) to help 

determine transport patterns and source contributions. EPA assessed wind direction and speed for the 

2008-2010 “ozone season” (March through October) in the Cincinnati-Middletown-Wilmington, OHKY-IN CSA. These analyses were conducted to better understand the fate and transport of precursor 

emissions contributing to ozone formation. EPA’s analysis of the NWS data indicate predominate 

south-southwest and west-southwest component for the Cincinnati-Middletown-Wilmington, OH-KYIN CSA. 

Factor 4: Geography/topography (mountain ranges or other air basin boundaries)

The geography/topography analysis evaluates the physical features of the land that might affect the 

airshed and, therefore, the distribution of ozone over the Area.

The Cincinnati-Middletown-Wilmington, OH-KY-IN Area does not have any geographical or 

topographical barriers significantly limiting air pollution transport within its air shed. Therefore, this 

factor did not play a significant role in this evaluation.
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Factor 5: Jurisdictional boundaries

Once we identified the general areas we anticipated we would recommend in the nonattainment area, we 

then considered existing jurisdictional boundaries for the purposes of providing a clearly defined legal 

boundary and to help identify the areas appropriate for carrying out the air quality planning and 

enforcement functions for nonattainment areas. Examples of jurisdictional boundaries include 

existing/prior nonattainment area boundaries for ozone or other urban-scale pollutants, county lines, air 

district boundaries, township boundaries, area covered by a MPOs, state lines, Reservation boundaries,

and urban growth boundary. Where existing jurisdictional boundaries were not adequate or appropriate 

to describe the nonattainment area, other clearly defined and permanent landmarks or geographic 

coordinates were considered.

The Cincinnati-Middletown-Wilmington, OH-KY-IN Area has previously established nonattainment 

boundaries associated with the both the 1-hour ozone and 1997 8-hour ozone NAAQS. The Cincinnati 

nonattainment boundary for the 1-hour ozone NAAQS included Boone, Campbell and Kenton Counties 

in their entireties in Kentucky; Butler, Clermont, Hamilton and Warren Counties in their entireties in 

Ohio. Whereas the Cincinnati nonattainment boundary for the 1997 8-hour ozone NAAQS included 

Boone, Campbell and Kenton Counties in their entireties in Kentucky, Butler, Clermont, Clinton, 

Hamilton and Warren Counties in their entireties in Ohio, and a portion of Dearborn County in Indiana. 

Kentucky and Indiana have recommended a different boundary for the 2008 ozone NAAQS for their 

portion of this Area. Ohio recommended the same as the previous boundary for their portion of this 

Area. 

Conclusion

Table 7 summarizes which factors discussed above support the inclusion of each Ohio county in the 

preliminary nonattainment area for the 2008 ozone NAAQS. Note that Table 7 covers all Ohio counties 

in the Cincinnati-Middletown-Wilmington, OH-KY-IN CSA, but that not all of these counties are 

included in the preliminary nonattainment area for the 2008 ozone NAAQS.

Table 7. Factors Supporting Inclusion of Ohio Counties in the Cincinnati-Middletown-Wilmington, 

OH-KY-IN Ozone Nonattainment Area for the 2008 Ozone NAAQS

County Violates 

Ozone 

Standard

High 

Emissions 

Population 

and Traffic 

Levels 

Meteorology

Favors 

Emissions 

Impact on 

Violating 

Monitor

Geography 

Favors High 

Ozone or 

Emissions 

Impact on 

Violating 

Monitor

Jurisdictional

Basis for 

Inclusion In 

Nonattainment 

Area

Indiana

Dearborn -

Partial X X NA X

Franklin X NA

Ohio X NA

Kentucky

Boone X X NA X

Bracken X NA
12

Campbell X X NA X

Gallatin X NA

Grant X NA

Kenton X X NA X

Pendleton X NA

Ohio

Brown X NA

Butler X X X NA X

Clermont X X NA X

Clinton X NA X

Hamilton X X X NA X

Warren X X X NA X

*Counties that EPA intends to designate as nonattainment are shown in bold.

Indiana:

For Indiana as shown in the table above, Franklin and Ohio Counties hardly contribute to the 

recommended Cincinnati-Middletown-Wilmington, OH-KY-IN ozone nonattainment area the 2008 

ozone NAAQS other than proximity. The areas are mostly rural with no point source emissions and 

minimal amounts of nonpoint source and mobile emissions. The areas were not included in the 

Cincinnati ozone nonattainment area for the 1997 ozone NAAQS. Franklin and Ohio Counties are again 

recommended to be excluded from the proposed nonattainment area. 

Lawrence Township in Dearborn County contains the American Electric Power (AEP)- Tanner’s Creek 

Generating Station that has high NOx and VOC emissions. Dearborn County also has the potential to 

have moderate mobile source and population related VOC and NOx emissions. The inclusion on 

Lawrence Township would be consistent with the Cincinnati ozone nonattainment area for the 1997 

ozone NAAQS. Lawrence Township contains the only major stationary source and accounts for the 

majority of the emissions for the area. The remainder of the county is fairly rural and is similar to 

Franklin and Ohio Counties. Therefore Lawrence Township in Dearborn County Indiana is a sufficient 

portion of Indiana to include in the preliminary Cincinnati-Middletown-Wilmington, OH-KY-IN ozone 

nonattainment area for the 2008 ozone NAAQS.

Kentucky:

For Kentucky based on the assessment of factors described above, EPA has preliminarily concluded that 

the following counties, Boone, Campbell and Kenton, should be included as part of the CincinnatiMiddletown-Wilmington nonattainment area because they are contributing to a violation in a nearby 

area. Source category emissions data indicate that mobile sources and area sources are not the primary 

contributors of NOx to ozone formation in the Cincinnati-Middletown -Wilmington Area. The analysis

reveals that mobile emissions make up approximately 28 percent of the total NOx in the CincinnatiMiddletown-Wilmington Area, and area sources make up approximately 12 percent of the total NOx 

emissions in the Cincinnati-Middletown -Wilmington Area. The total of mobile sources and area 

sources make up approximately 40 percent of the total NOx emissions in the Cincinnati area. However, 

VOC emissions in Cincinnati-Middletown -Wilmington Area are high for area and mobile sources. The 

analysis reveals that mobile emissions make up approximately 37 percent of the total VOC in the 

Cincinnati-Middletown-Wilmington Area, and area sources make up approximately 38 percent of the 

total VOC emissions in the Cincinnati area. The total of mobile sources and area sources make up 

approximately 75 percent of the total VOC emissions in the Cincinnati-Middletown-Wilmington Area,

area. Point sources in the area make up approximately 50 percent of the total NOx emissions and

approximatley10 percent of the total VOC emissions in the Cincinnati-Middletown-Wilmington Area.
13

Boone, Campbell, and Kenton counties’ NOx and VOC precursor emissions, high VMT along with 

population growth suggest that these counties should be considered for inclusion in the CincinnatiMiddletown-Wilmington Area. 

Ohio:

For Ohio the results in the above table show that Delaware, Fairfield, Franklin and Licking Counties 

should be included in the Columbus, OH ozone nonattainment area on the bases of a violation of the 

2008 ozone NAAQS and/or emissions that contribute to the violation of the 2008 ozone NAAQS.

The issue is less clear for Knox and Madison Counties due to the lack of a monitored ozone standard 

violation and relatively low VOC and NOx emissions, populations, and VMT in these counties. The 

only bases for including these counties in the intended, preliminary ozone nonattainment area for the 

2008 ozone NAAQS are the facts that the State of Ohio has recommended their inclusion in the 

nonattainment area and that these counties were included in the nonattainment area for the 2007 ozone 

NAAQS. Based on these facts, we agree with the State of Ohio that these counties should also be 

included in the Columbus, OH nonattainment area.

With the exception of those counties that comprise the 1997 8-hour ozone boundary for this Area, we 

believe that the remainder of the counties in the CSA do not contribute to the violations at the monitors 

in this Area and therefore are not necessary be considered as part of the nonattainment area.