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**Ohio Area Designations for the**  **2008 Ozone National Ambient Air Quality Standards**

**SUMMARY**

The table below identifies the area s and associated counties in Ohio that EPA intends to designate as nonattainment for the 2008 ozone National Ambient Air Quality Standards (NAAQS). 1 In accordance with section 107(d) of the CAA, EPA must designate an area (county or part of a county) as “ 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 nonattainment areas are provided below.

**Table 1. Intended Ozone Nonattainment Areas in Ohio** 

**Area Ohio Recommended**  **Nonattainment Counties EPA’s**  **Intended Nonattainment**  **Counties Nonattainment Areas**  **†** Cincinnati

- Middletown

Wilmington , OH

- KY

- IN ‡ Butler Clermont Clinton Hamilton
Warren Butler Clermont Clinton Hamil ton Warren Cleveland

- Akron

- Lorain,
OH Ashtabula Cuyahoga Geauga Lake Lorain Medina Portage Summit Ashtabula Cuyahoga Geauga Lake Lorain Medina Portage Summit Columbus, OH Delaware Fairfield Franklin
Knox Licking Madison Delaware Fairfield Franklin
Knox
L icking Madison

1 The primary 8

- hour hour ozone standard, set to protect human health, was revised on March 27, 2008 (73 FR 16436) from 0.08 parts per million (ppm) to 0.075 ppm. The secondary ozone standard, set to protect human welfare and the environment, was revised to be consistent with the primary ozone standard in all respects.2 † Nonattainment for both primary and secondary 2008 8

- hour ozone standards.

‡ Cincinnati

- Middletown

- Wilmington, OH

- KY

- IN is a multi

- state nonattainment area. Table 2 below identifies the counties in Ohio and in other states that EPA inte nds to designate as part of the nonattainment area.

EPA intends to designate the remaining counties in Ohio that are not listed in Table 1 above as “unclassifiable/attainment” for the 2008 ozone NAAQS.

The analysis below provides the basis for the intend ed nonattainment area boundaries. It relies on our analysis of whether and which monitors are recording violations of the 2008 ozone NAAQS, based on certified air quality monitoring data from 2008

- 2010 and on an evaluation of whether nearby areas are
cont ributing to such violations. EPA has evaluated contributions from nearby areas based on a weight

- of

- evidence analysis considering the factors identified below. EPA issued guidance on December 4, 2008 that identified these factors as ones EPA would consid er in determining nonattainment area boundaries, and recommended that states consider these factors in making their designation recommendations to EPA. 2

1. Air quality data (including the ozone design value calculated for each Federal Reference Method (FR M) or Federal Equivalent Method (FEM) monitor in the area);

2. Emissions and emissions

- related data (including location of sources, population, amount of emissions and emission controls, and growth patterns);

3. Meteorology (weather/transport patterns);

4. Geography and topography (mountain ranges and other basin boundaries affecting ozone levels and ozone precursor transport); and,

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

2 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

- Related Data,” which results in 5 categories of factors.3 Metropolit an Planning Organization (MPOs) and their covered area).

Ground

- level ozone is generally not emitted directly into the air, but is created by chemical reactions involving Nitrogen Oxides (NOx) and Volatile Organic Compounds (VOC) in the presence of sunlig ht. 3 Because NOx and VOC emissions from a broad range of sources over a wide area typically contribute to violations of the ozone standards, EPA believes it is important to consider whether there are contributing emissions from a broad geographic area. A ccordingly, 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). 4 All data and information used by EPA in this evaluation are t he latest available to EPA and/or provided to EPA by states or tribes.

In EPA’s designations guidance for the 2008 ozone NAAQS, EPA 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 and above for the 1

- hour ozone standard and EPA used the

sa me approach in the designation process for the 1997 ozone NAAQS. Where a violating monitor is not located in a CSA or CBSA, EPA’s September 4, 2008 guidance recommends 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 inform ation, including the locations and ozone design values (violating monitors only) of air quality monitors, county and other jurisdictional boundaries, existing maintenance boundary for the 1997 ozone NAAQS, Cincinnati

- Middletown

-

3 Peak ozone concentrations generally occur downwind of source areas on relatively sunny days with high temperat ures and relatively low wind speeds.

4 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).4 Wilmington, OH

- KY

- IN CSA bou ndary, and major transportation arteries.

**Figure 1. Cincinnati**

**- Middletown** 

**- Wilmington, OH** 

**- KY** 
**- IN Area** 

For purposes of the 1997 ozone NAAQS, as noted in Figure 1, portions of this area were designated nonattainment and subsequently redesignated to at tainment (maintenance). The boundary for the nonattainment area for the 1997 ozone NAAQS included the entire counties of Butler, Clermont, Clinton, Hamilton, and Warren in Ohio and Boone, Campbell, and Kenton in Kentucky and part of Dearborn County (Lawre nceburg Township) in Indiana.

In March 2009, Ohio recommended that Butler, Clermont, Clinton, Hamilton, and Warren Counties be designated as “nonattainment” for the 2008 ozone NAAQS based on air quality data from 2006

- 2008. In March 2009, Kentucky recomm ended that Boone, Campbell, and Kenton Counties be designated as nonattainment for the 2008 ozone NAAQS based on air quality data from 2006

- 2008.5 Additionally, Indiana, in March 2009, recommended that each county in the Indiana portion of the Cincinnati

- M iddletown

Wilmington, OH

- KY

- IN CSA be designated as “attainment” for the 2008 ozone NAAQS. In October 2011, Kentucky submitted an update to their 2009 recommendation, and revised their recommendation to “attainment” designations for each county in the Sta te. 5

The ozone data reflected in Figure 1 and summarized below 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 desig nate the counties in Ohio and Kentucky and the partial county in Indiana identified in Table 2 below as “nonattainment” for the 2008 ozone NAAQS as part of the Cincinnati

- Middletown

- Wilmington, OH

KY

- IN nonattainment area.

**Table 2. EPA’s Intended Nonatta**  **inment Counties for the Cincinnati** 

**- Middletown** 

**- Wilmington, OH** 

**- KY** 
**- IN Ozone Nonattainment** 
**Area**

Cincinnati

- Middletown

Wilmington, OH

- KY

- IN State

- Recommended Nonattainment Counties EPA Intended Nonattainment Counties Indiana None Dearborn

- Partial Kentucky No ne Boone Campbell
Kenton Ohio Butler Clermont Clinton Hamilton
Warren Butler Clermont Clinton Hamilton
Warren

**Factor Assessment**

**Factor 1: Air Quality Data**

5 Letters from Leonard K, Peters, Kentucky Energy and Environmental Cabinet Secretary to A. Stanley Meiburg and Gwendolyn Keyes Fleming regarding the initial and updated nonattainment boundary recommendations for the 2008 8

- hour ozone standard for Kentucky(October 13, 2011 and March 12, 2009, respectively); Letter from Ch ris Korleski, Director, State of Ohio Environm ental Protection Agency, to Lynn Buhl , Regional Administrator, U.S. Environmental Protection Agency, Region 5, regarding initial nonattainment boundary recommendations for Ohio for the 2008 ozone NAAQS (March 9 , 2009); Letter from Thomas W. Easterly, Commissioner, Indiana Department of Environmental Management, to Bharat Mathur, Deputy Regional Administrator, U.S. Environmental Protection Agency, Region 5, regarding the initial nonattainment boundary recommendat ions for the 2008 ozone NAAQS for Indiana.6 For this factor, we considered 8

- hour ozone design values (in ppm) for air quality monitors in counties in the Cincinnati

Middleton

- Wilmington, OH

- KY

- IN CSA based on data for the 2008

- 2010 period, which are the most recent years with fully

certified air quality data. A monitor’s design value is the metric or statistic that indicates whether that mo nitor attains a specified air quality standard. The 2008 ozone NAAQS are met at a monitor when the annual fourth

- highest daily maximum 8

- hour ozone concentrations, averaged over 3 years is 0.075 ppm or less. A design values is valid only if minimum data completeness requirements 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 design value for the county or area is determined by the monitor with the highe st individual design value.

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 f or 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 2008

- 2010 ozone design values for monitors and counties in the Cincinnati

- Middletown

- Wilmington, OH

- KY

- IN CSA are shown in Table 3.

**Table 3. Ozone Air Quality Data for the Cincinnati** 

**- Middletown** 

**** **Wilmington, OH**

**- KY** 
**- IN CSA** 

**State/County Site Number**  **2008**

**- 2010**  **8**

**- hour** 
**Ozone Design**  **Values**

**(ppm) Ohio:**  Butler 390170018 **0.078 †**  Butler 390170004 0.073 Clermont 390250022 0.071 Clinton 390271002 0.074 Hamilton 390610040 **0.076 †**  Hamilton 390610010 0.0737 Hamilton 390610006 **0.079 †** 
Warren 391650007 **0.078 †**  **Kentucky:**
Boone 210150003 0.065 Campbell 210373002 0.072 † Monitored violation of the 2008 ozone NAAQS.

Butler, Hamilton, and Warren Counties in Ohio show violations of the 2008 ozone NAAQS. Therefore, these counties are included in the intended ozo ne 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.

Please note that the state of Ohio, in its March 9, 2009 area designation recommendations and accompanying tec hnical support documentation, based its recommendations on 2006

- 2008 ozone data. Since these data no longer cover the most recent 3

- year period with quality

- assured, state

- certified data and have been supplanted by the more current 2008

- 2010 ozone data, w e are not reviewing the older ozone data covered by the state of Ohio.

**Factor 2: Emissions and Emissions**

**- Related Data** 

EPA evaluated emissions for ozone precursors (VOC and NOx) and other emissions

- related data that provide information on area contributi ons to ozone standard violations.

**Emissions Data**

EPA evaluated county

- level emission data for NOx and VOC derived from the 2008 National Emissions Inventory (NEI), version 1.5. These are the most recently available NEI emissions data. (See http://www.epa.gov/ttn/chief/net/2008inventory.html ) Significant emission levels in a nearby area indicate the potential for the area to contribute to the observed ozone standard violation.

Table 4 shows the 2008 emissions of VOC and NOx (tons per year (tpy)) for all counties in the Cincinnati

- Middletown

- Wilmington,
OH

- KY

- IN CSA. This table also indicates which of the counties were recommended to be nonattainment for the 2008 ozone NAAQS by their r espective states.8 **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
Fran klin 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

**Emissions Observations By State**

**Ohio:**

From the Ohio emissions data in Table 4, it can be seen that comparatively 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 and Clinton Counties, Ohio are significantly smaller than those originating in the higher emitting counties elsewhere in the Cincinnati

- Mid dletown

Wilmington, OH

- KY

- IN CSA. This supports the exclusion of Brown County from the recommended ozone nonattainment area for the 2008 8

- hour ozone NAAQS, but not the exclusion of Clinton County based on consideration of jurisdictional boundaries (see t he discussion of Factor 5 below).

**Indiana:**9 From the Indiana emissions data in Table 4, it can be se en that comparatively high 2008 VOC and NOx emissions in the vicinity of the violating counties ori ginate from Dearborn County. Emissions from this county 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 Generati ng Station located in the
Lawrence burg Township

, adjacent to the recommended nonattainment

area.

The VOC and NOx emissions from Franklin and Ohio Count ies in Indiana are comparatively smaller than those originating in the higher emitting counties elsewh ere in the Cincinnati

- Middletown

Wilmington, O H

- KY

- IN CSA. This supports 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 emi ssions 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. K enton 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 29 percent of its VOC emission coming from area sources and 23 percent of its VOC e missions 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 it s 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 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.

**Population, Population Density, and Degree of Urbanization**

EPA evaluated the population and vehicle use cha racteristics and population trends of the area as indicators of the probable10 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

c ombustion, 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 Traveled (VMT ) growth in a county on the urban perimeter signifies increasing integration with the urban core area, and indicates that it may be appropriate to include this county in the ozone nonattainment area, particularly if this county already has moderate or high er VOC and/or NOx emissions. Table 5 shows the 2010 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**

  ** Midd** **letown**

**- 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:**
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 Sources: U.S. Census Bureau population estimates for 2010 as of August 4, 2011. ( http://factfinder2.census.gov/faces/tableservices/jsf/pages/pro ductview.xhtml?pid=DEC_10_PL_GCTPL2.STO5&prodType=table )11 **Population Observations By State**

**Ohio:**

For Ohio, the population data show that Butler, Clermont, Hamilton, and Warren Co unties have comparatively large populations and population densities and are densely populated. This implies that the population

- related VOC and NOx emissions in these counties are relatively high. In addition, the population change percentages in Butler , Clermont, and Warren Counties between 2000 and 2010 exceed the population change percentage for the entire Cincinnati

- Middletown

- Wilmington, OH

KY

- IN area, implying that the population

- related emission contributions from these counties are increasing com pared to those from other counties in the Cincinnati

- Middletown

Wilmington, OH

- KY

- IN area.

**Indiana:**

The populations of the Indiana counties in the Cincinnati

Middletown

- Wilmington, OH

- KY

- IN CSA are smaller than those of the Ohio counties and larger Kentu cky counties in this CSA, but Dearborn County has a moderate population implying moderate population

- related VOC and NOx emissions. In addition, the population change percentage change from 2000 to 2010 in Dearborn County is greater than the population ch ange percentage for the entire Cincinnati

- Middletown

- Wilmington, OH

- KY

- IN CSA, implying that the population

- related emission contribution from this county may be increasing relative to those from other counties in the Cincinnati

- Middletown

- Wilmington, OH

- K Y

- IN area. Ohio County, Indiana also has a greater population change percentage as well, but the lower population in this county causes this change to be less significant.

**Kentucky:**

For Kentucky, Boone, Campbell, and Kenton Counties have relatively hig h populations and population densities when compared to the rest of the CSA. Bracken, Gallatin, Grant and Pendleton Counties are smaller when compared to the counties included in the non

- attainment recommendation. Boone County at 37 percent growth and Wa rren County at 32 percent growth had the highest percentage of population growth for any of the count ies in the Cincinnati

- Middletown

**-** Wilmington CSA. Other counties in this CSA did not have as large of a population percentage change
, with the ir growth rat es ranging from a 2 to 10 percent12 increase. Hamilton County population decreased by 5 percent from 2000

- 2010.

**Traffic and Commuting Patterns**

EPA evaluated the total VMT for each county in the Cincinnati

Middletown

- Wilmington, OH

- KY

- IN CSA. In combinati on with the population/population density data and the location of main transportation arteries (see above area map), 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 relatively high motor vehicle emissions that may significantly contribute to ozone formation and transport that contributes to nonattainment in the urban area. Rapid population or VMT growth in a county
on t he urban perimeter signifies increasing integration with the core urban area, and suggests that this county should be included in the ozone nonattainment area, particularly if the VOC and/or NOx emissions in this county are a significant portion of the tot al emissions in the nonattainment area.

Table 6 shows the traffic levels, total 2008 VMT, in each county in the Cincinnati

- Middletown

- Wilmington, OH

- KY

- IN CSA.

**Table 6. Traffic Levels in the Cincinnati**

**- Middletown** 

**** **Wilmington, OH**

**- KY** 
**- IN CSA** 

**State/County S**  **tate Recommended**  **Nonattainment 2008 VMT**  ***** **(million miles)**  **Indiana:** Dearborn No 904 Franklin No 316 Ohio No 63 **Kentucky:**
Boone No 1,095 Bracken No 89 Campbell No 1,005 Gallatin No 278
Grant No 432
Kenton No 1,669 Pendleton No 182 **Ohio:**
Brown No 413 Butler Yes 2,469 Clermont Yes 1,464 Clinton Yes 655 Hamilton Yes 7,391
Warren Yes 1,64013 **Area**
**- wide**  20,063

* MOBILE model VMT are those input into the NEI version 1.5 use to compute the mobile source portion of the NEI emissions summarized ab ove in Table 4.

**VMT Observations By State**

**Ohio:**

For Ohio, the VMT data show that VMT levels in Butler, Clermont, Hamilton, and Warren Counties are comparatively higher than those in Brown and Clinton Counties and, accumulatively, are a significant porti on of the total VMT for the Cincinnati

Middletown

- Wilmington, OH

- KY

- IN CSA.

**Indiana:**

For Indiana, the dat a show that VMT level in D earborn County is a comparatively high portion of the total VMT for the Cincinnati

- Middletown

- Wilmington, OH

- KY

- IN CSA.

**Ke ntucky:** 

T he 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

.

**Additional Emissions**

**- Related Data Discussed in Ohio’s March 9,**  **2009 Designation Recommendation Submittal**

The State of Ohio, through the Ohio Environmental Protection Agency (OEPA), has provided a detailed discussion of the county

specific VOC and NOx emissions, populations, and traffic and commuting patterns for the Ohio counties in the Cincinnati

Middletown

- Wilmington, OH

- KY

- IN CSA. These data support our conclusions discussed above, but also allow us to further refine our decisions for F actor 2 for the Ohio portion of the CSA. This is particularly true for growth in county populations and traffic levels and the inter

- county impact of commuter traffic.

With regard to emissions, Ohio clearly shows that both VOC and NOx daily emissions in Brown County are considerably lower than many other counties in the Cincinnati

- Middletown

- Wilmington, OH

KY

- IN CSA. This confirms our conclusions that Brown County14 emissions are relatively low and would not support inclusion of this county in the ozone no nattainment area.

Ohio has projected county

- populations through 2030. These population projections show that populations in Clinton and Brown Counties will remain comparatively low through 2030. Whereas, the populations of Butler, Clermont, Hamilton, an d Warren Counties will either significantly increase or will remain relatively high through 2030.

Estimated daily VMT in Brown County are shown to be largely unchanged beginning in 2001 through 2007, and daily VMT in Hamilton County are estimated to be si milarly unchanged between 1990 and 2007. In contrast, daily VMT levels have shown significant growth trends in Butler, Clinton, Clermont, and Warren Counties between 1990 and 2007.

The State of Ohio notes that the vast majority of workers traveling out o f county from Butler, Warren, and Clermont Counties commute to Hamilton County. This conclusion is supported by tabulated inter

- county commuter numbers and percentages in Ohio’ March 9, 2009 submittal. It is also noted that approximately 15 percent of th e Hamilton County workers commute outside of the county, with the majority traveling to Butler County, with significant numbers of commuters also traveling from Hamilton County to Warren and Clermont Counties. The commuter numbers for Brown County show a much smaller number commuters traveling to or from other counties in the Cincinnati

Middletown

- Wilmington, OH

- KY

- IN CSA.

Considering all of the information provided by the State of Ohio supports the conclusion that there is strong urban integration of But ler, Clermont, Hamilton, and Warren Counties. In contrast, Clinton and Brown Counties are not significantly integrated with the Cincinnati urban area. This favors the exclusion of Brown County from the Cincinnati

- Middletown

Wilmington, OH

- KY

- IN ozone non attainment area for the 2008 ozone NAAQS. Clinton County, however, cannot be excluded from the ozone nonattainment area due to jurisdictional boundary considerations, as discussed for Factor 5 below.

**Factor 3: Meteorology (Weather/Transport Patterns)**

E PA evaluated available meteorological data to help determine how meteorological conditions, particularly transport conditions, affect the fate and transport of ozone and ozone precursors contributing to ozone formation in the Cincinnati

-15 Middletown

- Wilmingt on, OH

- KY

- IN CSA. The wind direction percentages show that there is no “preferred” wind direction during the summertime. Transport winds can and do blow from all directions into the counties with the recorded violations of the 2008 ozone NAAQS. There is , however, an indication that winds from south

- southwest and west

- southwest (collectively, the southwest quadrant) may be more prevalent than winds from other wind directions during the summertime in all three ozone standard violation counties.

**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

- Midd letown

- Wilmington, OH

- KY

- IN CSA 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.

**Factor 5: Jurisdictio nal Boundaries** 

Once we identified the general area that we anticipated we would recommend as nonattainment for the 2008 ozone NAAQS, we then considered existing jurisdictional boundaries for the purposes of providing a clearly defined legal boundary and t o help identify the area appropriate for carrying out the air quality planning and enforcement functions for an ozone nonattainment area. Examples of jurisdictional boundaries include existing/prior nonattainment boundaries for ozone or other urban

- scale pollutants, county boundaries, air district boundaries, township boundaries, areas covered by metropolitan planning organizations, state lines, and Reservation boundaries. Where existing jurisdictional boundaries are not adequate or appropriate to describ e the nonattainment area, other clearly defined and permanent landmarks or geographic coordinates may be considered.

The Cincinnati

- Middletown

**-** Wilmington, OH

- KY

- IN a rea has previously established nonattainment boundaries associated with the both the 1

- hou r 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 in16 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 (Lawrenceburg Township) in Indiana . Kentucky and Indiana have recommended a different nonattainment boundary for the 2008 ozone NAAQS for their portion of this a rea. Ohio recommended the same boundary as the 1997 ozone NAAQS nonattain ment boundary for their portion of this a rea. With the exception of those counties (and partial county) that comprise the 1997 8

- hour ozone boundary for this a rea, we believe that the remainder of the counties in the CSA do not contribute to the viol ation s at the monitors in this a rea and
, therefore
, are not necessary for consideration as part of the nonattainment area

.

**Conclusion**

**Ohio:**

Based on the assessment of factors described above, EPA has preliminarily concluded that the following Ohio counties s hould be included in the Cincinnati

- Middletown

- Wilmington, OH

- KY

- IN ozone nonattainment area because they are either violating the 2008 ozone NAAQS or contributing to a violation of the 2008 ozone NAAQS within this preliminary nonattainment area: Butler;
C lermont; Clinton; Hamilton; and, Warren.

Table 8a summarizes which factors, discussed above, support the inclusion of each Ohio county in the intended nonattainment area for the 2008 ozone NAAQS. Note that Table 8a covers all Ohio counties in the Cincinn ati

- 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 8a. Factors Supporting Inclusion of Ohio Counties in the Cincinnati** 

**- Middletown** 

**- Wilmington, OH** 

**- K**  **Y**
**- 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** 

**Monit or**  **Jurisdictional Basis for**  **Inclusion In Nonattainment** 
**Area**

Butler X X X NA X Clermont X X NA X17 Clinton X NA X Hamilton X X X NA X
Warren X X X NA X

The results in the above table show that Butler, Hamilton, and Warren Counties, at minimum, shou ld be included in the ozone nonattainment area based on air quality data. In addition, these counties also have comparatively high VOC and NOx emissions, populations (high population

- related emissions), and traffic levels (traffic

- related emissions), whic h favor their inclusion in the ozone nonattainment area.

Clermont County has comparatively high VOC and NOx emissions and relatively high populations and traffic levels, which, based on meteorological considerations, can also contribute to the monitored o zone standard violations in EPA’s intended ozone nonattainment area. Therefore, Clermont County should also be included in the preliminary ozone nonattainment area.

Clinton County has no monitored ozone standard violations and generally lacks the higher VOC and NOx emissions and high population and traffic levels of the other Ohio counties discussed above. Therefore, these factors do not favor the inclusion of Clinton County in the intended ozone nonattainment area. However, it is noted that Clinton Cou nty has historically been included in the Cincinnati ozone nonattainment area for the 1997 ozone NAAQS. In addition, the State of Ohio, in its March 9, 2009 ozone designation submittal, has recommended that Clinton County should be included in the ozone n onattainment area for the 2008 ozone NAAQS. Based on the jurisdictional factor and the State’s recommendation, we are including Clinton County in the intended, preliminary Cincinnati

- Middletown

Wilmington, OH

- KY

- IN ozone nonattainment area for the 2008 oz one NAAQS.

Finally, it is noted Brown County lacks ozone standard violations, and the comparatively high emissions, populations, and traffic levels of other Ohio counties in the Cincinnati

Middletown

- Wilmington, OH

- KY

- IN CSA. In addition, this county

was not included in the nonattainment area for the 1997 ozone NAAQS and Ohio has not recommended the inclusion of this county in the ozone nonattainment area for the 2008 ozone NAAQS. Based on all of these factors and facts, we are not including Brown
Cou nty in the intended Cincinnati

- Middletown

- Wilmington, OH

- KY

IN ozone nonattainment area for the 2008 ozone NAAQS.

**Indiana:**18 Based on the assessment of factors described above, EPA has preliminarily concluded that the following Indiana county should be includ ed in the Cincinnati

- Middletown

- Wilmington, OH

- KY

- IN ozone nonattainment area because they are either violating the 2008 ozone NAAQS or contributing to a violation of the 2008 ozone NAAQS within this preliminary nonattainment area: Lawrence Township in Dea rborn County.

Table 8 b summarizes which factors

, discussed above

, support the inclusion of each I ndiana county in the intended nonattainment area for the 2008 ozone NAAQS. Note that Table 8 b covers all Indiana counties in the Cincinnati

- Middletown

- Wilmin gton, OH

- KY

IN CSA, but that not all of these counties are included in the preliminary nonattainment area for the 2008 ozone NAAQS.

**Table 8b. Factors Supporting Inclusion of Indiana Counties in the Cincinnati** 

**- Middletown** 

**- Wilmington, OH** 

**- KY** 
**- IN Ozone** 
**Nonatta inment Area for the 2008 Ozone NAAQS** 

County Monitored Violat ion for 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 Dearborn

- Partial X X NA X

EPA has preliminarily concluded that F ranklin and Ohio Counties are not expected to c ontribute to the ozone standard violations in the recommended Cincinnati

- Middletow n

- Wilmington, OH

- KY

- IN ozone nonattainment area . The areas are mostly rural with no point source emissions and minimal amounts of nonpoint source and mobile emissions. Franklin and Ohio Counties were not included in the Cincinnati ozone nonattainment are a for the 1997 ozone NAAQS. EPA has preliminarily concluded that Franklin and Ohi o Counties are to be excluded from the proposed nonattainment

area.

Lawrenceburg Township in Dearborn County contains the American Electric Power (AEP)

– Tanner’s Creek Gen erating Station and 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 of Lawrenceburg Township in the Cincinnati

- Middletown

- Wilmington, OH

- KY

- IN ozone nonattainment area would be consistent with the ozone nonattainment area for the 1997 ozone NAAQS. Lawrenceburg Township contains the only major stationary source in the Indiana portion of Cincinnati

- Middletown

- Wilmington, OH

- KY

- IN CSA and accoun ts for the majority of the VOC and NOx emissions19 in the Indiana portion of this area. The remainder of Dearborn County is fairly rural and is similar to Franklin and Ohio Counties. The inclusion of the Lawrenceburg Township portion of Dearborn County, In diana in the intended Cincinnati

- Middletown

Wilmington, OH

- KY

- IN nonattainment area for the 2008 ozone NAAQS is sufficient to account for the contribution of this county.

**Kentucky:**

Table 8c summarizes which factors discussed above support the inclusion o f Kentucky counties in the intended nonattainment area for the 2008 ozone NAAQS. Note that Table 8c covers all Kentucky counties in the Cincinnati

- Middletown

- Wilmington, OH

KY

- IN CSA, but that not all of these counties are included in the preliminary nona ttainment area for the 2008 ozone NAAQS.

**Table 8c. Factors Supporting Inclusion of Kentucky Counties in the Cincinnati** 

**- Middletown** 

**- Wilmington, OH** 

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

County Monitored Violat ion for Ozone Standard High E missions 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 Boone X X NA X Campbell X X N A X Kenton X X NA X

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 Cincinnati

- Middletown

- Wilmington nonattainm ent 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 a rea. The analysis reveals that mobile emissions make up approximately 28 percent of the total NOx in the Cincinnati

- Middletown

- Wilmington

a rea, 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 a rea are high for area and mobile sources. The analysis re veals that mobile emissions make up approximately 37 percent of the total VOC in the Cincinnati

- Middletown

Wilmington a rea, and area sources make up approximately 38 percent of the total VOC emissions in the Cincinnati area. The20 total of mobile sources an d area sources make up approximately 75 percent of the total VOC emissions in the Cincinnati

Middletown

- Wilmington area . Point sources in the area make up approximately 50 percent of the total NOx emissions and approximatley10 percent of the total VOC emi ssions in the Cincinnati

- Middletown

- Wilmington Area.

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 Cincinnati

- Middletown

- W ilmington , OH

- KY

- IN ozone nonattainment

area

.
**Technical Analysis for Cleveland**

**- Akron** 

**- Elyria, OH** 

Figure 2 is a map of the intended Cleveland

- Akron

- Elyria, OH ozone nonattainment area for the 2008 ozone NAAQS. The map provides other relevant information, including the locations and ozone design values of air quality monitors recording violations of the 2008 ozone NAAQS, county and other jurisdictional boundaries, existing maintenance boundary for the 1997 ozone NAAQS, Cleveland

- Akron

- Elyria, OH CSA bounda ry and major transportation arteries.

**Figure 2. Cleveland**

**- Akron** 

**- Elyria, OH Area** 21 For purposes of the 1997 ozone NAAQS, as noted in Figure 2, portions of this area were designated nonattainment and subsequently redesignated to attainment (maintenance). The boundary for the nonattainment area for the 1997 ozone NAAQS included all Ohio counties in the Cleveland

- Akron

- Elyria, OH CSA. In March 2009, Ohio recommended that the same counties in Ohio be designated as nonattainment for the 2008 ozone NAAQS bas ed on air quality data from 2006

- 2008. These data are from 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 the same 8 c ounties in Ohio (identified in Table 9 below) as “nonattainment” for the 2008 ozo ne NAAQS for the Cleveland

Akron

- Elyria, OH nonattainment area.

**Tab le 9. EPA’s Intended**  **Nonattainment Counties for the Cleveland** 

**- Akron** 

**- Elyria, OH Ozone Nonattainment Area** 

**S tate** 
**- Recommended Nonattainment**  **EPA Intended Nonattainment Counties**22 **Counties in Ohio in Ohio**  Ashtabula Cuyahoga Geauga Lake Lorain Medina Portage Summit Ashtabula Cuyahoga Geauga Lake Lorain Medina Portage Summit

**Factor Assessment**

**Factor 1: Air Qualit y Data** 

For this factor, we considered 8

- hour ozone design values (in ppm) for air quality monitors in counties in the Cleveland

Akron

- Elyria, OH CSA based on data for the 2008

- 2010 period, which are the most recent years with fully

- certified air quality d ata. As discussed above, a monitor’s design value 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

ozone concentrations, averaged over 3 years is 0.075 ppm or less. A design value is valid only if minimum data completeness requirements are met. See 40 CFR part 50 Appendix P. Where several monitors are located in a county (or a designated nonattainment are a or maintenance area), the design value for the county or area is determined by the monitor with the highest individual design value.

The 2008

- 2010 ozone design values for ozone monitors in the Cleveland

- Akron

- Elyria, OH CSA are shown in Table 10.

**Table 10. Ozone Air Quality Data for the Cleveland** 

**- Akron** 

**** **Elyria, OH CSA**

**County Site Number**  **2008**

**- 2010**  **8**

**- Hour**  **Ozone Design**  **Values**

**(ppm)** Ashtabula 390071001 **0.077 †**  Cuyahoga 390350064 0.068 Cuyahoga 390350034 0.075 Cuyahoga 390355002 0.075 Geauga 390550004 **0 .077**  **†** Lake 390850003 **0.076 †**  Lorain 390930018 0.070 Medina 391030004 0.07023 Portage 391331001 0.067 Summit 391530020 0.075 **†** Monitored violation of the 2008 ozone NAAQS.

From Table 10, it can be seen that Ashtabula, Geauga, and Lake Counties in Ohio show violations of the 2008 ozone NAAQS for the period of 2008

- 2010. Therefore, these counties must be included in the ozone nonattainment area. As noted above, a county (or partial county) must also be designated nonattainment if it contributes to an a ir quality standard violation in a nearby area. Each county in the Cleveland

- Akron

- Elyria, OH CSA has been evaluated, as discussed be low, based on the five factors summarized above and other relevant information to determine whether it contributed to the violations of the 2008 ozone NAAQS in Ashtabula, Geauga, and Lake Counties.

Please note that the State of Ohio, in its March 9, 2009 area designation recommendations and accompanying technical support documentation, based its area recommendations on 2006

- 2008 ozone data. Since these data no longer cover the most recent 3

- year period with quality

- assured, state

- certified data and have been supplanted by the more current 2008

- 2010 ozone data, we are not reviewing the older ozone data covered by the state of Ohio.

**Factor 2: Emissions and Emissions**

**- Related Data** 

EPA evaluated emissions fo r VOC and NOx and other emissions

related data (primarily county population, population density, and traffic levels, and projected growth rates for county populations ) that provide information on area contributions to local ozone standard violations.

**Emissions Data**

EPA evaluated county

- level emission data for NOx and VOC derived from the 2008 NEI, version 1.5. These are the most recently available NEI emissions data. (See http://www.epa.gov/ttn/chief/net/2008inventory.html ) Significant emission levels in a nearby area indicate the potential for the area to contribute to the observed ozone standard violati on.

Table 11 shows the 2008 emissions of NOx and VOC (tons per year) for all counties in the Cleveland

- Akron

- Elyria, OH CSA. This table also indicates which of the counties were recommended to be nonattainment for the 2008 ozone NAAQS by the State of O hio.24 **Table 11. Total 2008 VOC and NOx Emissions (tons/year) in the Cleveland** 

**- Akron** 

**- Elyria, OH CSA** 

**State/County State Recommended**  **Nonattainment? VOC Emissions**  **(tpy) NOx Emissions**  **(tpy)** Ohio: Ashtabula Yes 10,411 9,860 Cuyahoga Yes 42,981 38,698 Geaug a Yes 3,891 2,237 Lake Yes 10,382 19,286 Lorain Yes 11,646 15,261 Medina Yes 5,918 5,101 Portage Yes 6,137 5,656 Summit Yes 18,699 14,924 **CSA Total** 110,065 111,022

From the emissions data in Tab le 11, it can be seen that comparatively high 2008 VO C and NOx emissions i n the vicinity of the violating counties originate in the following counties: Ashtabula, Cuyahoga, Lake, Lorain, and Summit. Emissions from these counties in 2008 account for 85.5 percent of the VOC emissions and 88.3 percent of NOx e missions for the entire Cleveland

- Akron

- Elyria, OH CSA.

The VOC and NOx emissions from Geauga, Medina, and Portage Counties are significantly smaller than those originating in the higher emitting counties within the Cleveland

- Akron

- Elyria, OH CSA . Note, however, that the collective emissions from these “lower emissi on” counties does constitute 12 to 15 percent of the CSA total emissions. So, even though individual VOC and NOx emissions are relatively low in the low emissions counties, their collective em ission levels are equivalent to the emission levels for counties we are intendi ng to include in the

non attainment area for the 2008 oz one NAAQS. On this basis, we conclude that these counties may have the potential to contribute to ozone standard violatio ns in the Cleveland

- Akron

Elyria, OH area.

**Population, Population Density, and Degree of Urbanizaion**

EPA evaluated the population and vehicl e use characteristics and population trends of the area as indicators of the probable location and magnitude of non

- point source emissions. These include ozone

- creating emission 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, which can contribute to local and downwind high ozone concentrations. Rapid population25 or VMT growth in a county on the urban perimeter signifies increasing integration with the urban core area, and indicates that it may be appropriate to include this county in the ozone nonattainment area, particularly if this county already has moderate or higher VOC and/or NOx emissions.

Table 12 shows the 2010 population, population density, and population growth information for each county in the Cleveland

Akron

- Elyria, OH CSA.

**Table 12. Population and Population Growth in the Cleveland**

  ** Akron**

**- Elyria, OH 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)** 

Ohio: Ashtabula Yes 101,497 0.14

- 1,249

- 1 Cuyahoga Yes 1,280,122 2.79

- 111,989

- 8 Geauga Yes 93,389 0.23 2,180 2 Lake Yes 230,041 0.99 2,385 1 Lorain Yes 301,356 0.61 16,22 4 6 Medina Yes 172,332 0.41 20,496 13 Portage Yes 161,419 0.32 9,036 6 Summit Yes 541,781 1.29

- 1,797 0 **Area Totals 2,881,937**  **0.79**

**- 64,714** 

**- 2**  Sources: U.S. Census Bureau population estimates for 2010 as of August 4, 2011. ( http://factfinder2.census.gov/faces/tableservices/jsf/pages/pro ductview.xhtml?pid=DEC_10_PL_GCTPL2.STO5&proType=table )

The population data show that Cuyahoga, Lake, Lorain, Medina, Portage, and Summit Counties have comparatively high populations and population densities. This implies that these counties are generally urbanized and relatively integrated with the urban core of the Cleveland

- Akron

- Elyri a, OH CSA. It also implies that the population

- related VOC and NOx emissions in these counties are comparatively high and contribute to the ozone standard violations in the Cleveland

- Akron

- Elyria, OH CSA

.
The counties that experienced the largest popul ation growth for the 2000

- 2010 period are Lorain and Medina . As noted above, this implies an incre asing integration of these counties with the urban core of the Cleveland

- Akron

- Elyria, OH CSA, and favors the i nclusion of these counties in the ozone nonatt ainment area.26 Although some counties, to the contrary are experiencing population declines (Cuyahoga and Summit Counties) , their base populations remain high, implying that they should not be excluded from the ozone nonattainment area.

**Traffic and Commuti ng Patterns** 

EPA evaluated the total VMT for each county in the Clevelan d

Akron

- Elyria, OH CSA . In combination with the county

- specific population/population density data and the locations of the main transportation arteries (see above), this information helps identify the probable locations of non

- point source emis sions. A county with high VMT is generally an integral part of an urban area and indicates the presence of relatively high motor vehicle emissions that may significantly contribute to ozone for mation and transport that contributes to ozone standard violations in or downwind of the urban area. Rapid population or VMT growth in a county on the urban perimeter signifies increasing integration with the urban core area, and indicates that this
count y should be included in the ozone nonattainment area, particularly if the VOC and/or NOx emissions in this county are a significant portion of the total emissions in the nonattainment area.

Table 13 show the traffic levels, 2008 VMT, in each county in the Cleveland

- Akron

- Elyria, OH CSA.

**Table 13. Traffic Levels in the Cleveland**

**- Akron** 

**- Elyria, OH CSA** 

**State/County State Recommended**  **Nonattainment? 2008 VMT (million miles)** 

Ohio: Ashtabula Yes 1,039 Cuyahoga Yes 10,148 Geauga Yes 736 Lake Yes 2,111
Lo rain Yes 2,359 Medina Yes 1,532 Portage Yes 1,651 Summit Yes 5,471 Area Total 25,048

The VMT data show that VMT levels in all counties, with the exception of Geauga County, are relatively high. This implies that mobile source emissions in these coun ties are comparatively high and contribute to ozone stand ard violations in the Cleveland

- Akron

- Elyria, OH area.27 VMT in Geauga County are comparatively lower than those in other counties in this area. This, however, does not imply that this county should be excluded from the ozone nonattainment area since this county has a monitored violation of the 2008 ozone NAAQS.

**Additional Emissions**

**- Related Data Discussed in Ohio’s March 9,**  **2009 Designation Recommendation Submittal**

OEPA has provided typical daily, c ounty

- specific total VOC and NOx emissions for 2005 and 2009 for each of the counties in the Cleveland

- Akron

- Elyria, OH CSA. These data confirm the conclusions we have drawn above using county

- specific annual emissions.

OEPA has provided population proj ections through 2030 for each of the counties in the CSA. These data show significant population growth trends in Geauga, Lake, Lorain, Medina, Portage, and Wayne Counties. Populations are pro jected to be substantially unchanged in Ashtabula and Summit C ounties through 2030 . Populations are projected to decline over time in Cuyahoga County, however, the population in this county is projected to remain above 1 million through 2030.

OEPA provided graphs of daily VMT levels plotted for the period of 1990

- 2 007 for each of the counties in the CSA. This visual VMT trend information shows that daily VMT grew moderately during the 1990

- 2007 period for Ashtabula, Cuyahoga, Geauga, Lake, Lorain, Medina, Portage, and Summit Counties.

OEPA provided inter

- county co mmuter numbers and percentages for each of the counties in the Cleveland

- Akron

- Elyria, OH CSA. These numbers show a strong inter

- county commuting pattern throughout the CSA.

Collectively, the OEPA

- supplied population and traffic data support the conclusi on that all of the counties in the Cleveland

- Akron

- Elyria, OH CSA, with the exception of Ashtabula County, are relatively integrated with the urban, industrial core of this are a. Therefore, these data support including Cuyahoga, Geauga, Lake, Lorain, Medi na, Portage, and Summit Counties in the Cleveland

- Akron

- Elyria, OH ozone nonattainment area. As noted elsewhere in this technical review, Ashtabula County must be included in this ozone nonattainment area as the result of its monitored violation of the 20 08 ozone NAAQS.

**Factor 3: Meteorology (Weather/Transport Patterns)**28 EPA evaluated available meteorological data to help determine how meteorological conditions, particularly transport conditions, affect the fate and transport of ozone and ozone
precursor s contributing to ozone formation in the Cleveland

Akron

- Elyria, OH CSA. EPA examined the frequency distribution of wind directions for the four seasons of the year by averaging National Weather Service direction

- sorted wind directions for each county for a 30 year period

**.** To apply the results of this data analysis to the Cleveland

- Akron

- Elyria, OH CSA, we have considered the wind direction (direction from which winds are blowing, reflecting directions to potential source areas) frequencies during the summer months (June

- August) for the three Ohio counties with recorded violations of the 2008 ozone NAAQS (See Table 10). Therefore, we have considered wind direction distributions for Ashtabula, Cuyahoga, and Geauga Counties in Ohio.

Table 14 shows the summ ertime 30

- year averaged percentages of wind directions (winds blowing into the subject county from the specified wind direction sector) for the three ozone standard violation counties in the Cleveland

- Akron

- Elyria, OH CSA.

**Table 14. Averaged Summertime W ind Direction Percentages for**  **Ozone Standard Violation Counties in the Cleveland**

**- Akron** 

**- Elyria,** 
**OH CSA**

**Wind Direction Ashtabula County**  **Geauga County Lake County**  North

- Northeast 10.1 13.4 14.8
East

- Northeast 7.1 6.1 5.5
East

- Southeast 8.5 8.3 6.9 South

- Southeast 10.1 9.5 9.7 South

- Southwest 25.1 24.8 26.8
West

- Southwest 15.8 16.6 16.2
West

- Northwest 13.2 10.9 10.2 North

- Northwest 10.1 10.3 10.0

The wind direction percentages show that there is no single “preferred” wind direction during the summert ime, when the highest ozone concentrations are generally monitored. Transport winds can and do blow from all directions in the counties with the recorded violations of the 2008 ozone NAAQS. There is, however, an indication that winds from the south

- south west and
west

- southwest may be more prevalent than winds from other wind directions during the summertime in all three ozone standard violation counties.29 Unfortunately, EPA’s wind direction percentage data do little to shed light on which counties in the Cleveland

- Akron

- Elyria, OH CSA are the most important from an ozone and ozone precursor transport standpoint. The wind direction s considered have not been sorted based on peak ozone concentrations or specifically for high ozone days, the timing of peak oz one concentrations, wind speeds, or other factors that could have been used to isolate the most critical ozone precursor source areas.

**Factor 4: Geography/Topography (Mountain Ranges or Other Air Basin Boundaries)** 

The geography/topography analysis eva luates the physical features of the land that might affect the airshed and, therefore, the distribution of ozone over the area.

The Cleveland

- Akron

- Elyria, OH CSA does not have any geographical or topographical barriers significantly limiting air pollutio n transport within its air shed. Therefore, this factor did not play a significant role in this evaluation.

**Factor 5: Jurisdictional Boundaries**

Once we identified the general area that we anticipated we would recommend as nonattainment for the 2008 ozo ne NAAQS, we then considered existing jurisdictional boundaries for the purposes of providing a clearly defined legal boundary and to help identify the area appropriate for carrying out the air quality planning and enforcement functions for an ozone nonatt ainment area. Examples of jurisdictional boundaries include existing/prior nonattainment boundaries for ozone or other urban

- scale pollutants, county boundaries, air district boundaries, township boundaries, areas covered by metropolitan planning organiza tions, state lines, and Reservation boundaries. Where existing jurisdictional boundaries are not adequate or appropriate to describe the nonattainment area, other clearly defined and permanent landmarks or geographic coordinates may be considered.

The po rtion of the Cleveland

- Akron

- Elyria, OH CSA that we are considering as designating as nonattainment for the 2008 ozone NAAQS has a previously established nonattainment boundary associated with the 1997 8

- hour ozone NAAQS. The State of Ohio has recommended the same counties (as included in the 1997 8

- hour ozone nonattainment area) in Ohio to be included in the boundary of the nonattainment area for the 2008 ozone NAAQS. The prior inclusion of these counties in the ozone nonattainment30 area for the 1997 ozon e NAAQS forms the primary jurisdictional basis for the inclusion of these counties in the nonattainment area for the 2008 ozone NAAQS.

**Conclusion**

Based on the assessment of factors described above, EPA has preliminarily concluded that the following Ohio counties should be included in the Cleveland

- Akron

- Elyria, OH ozone nonattainment area because they are either violating the 2008 ozone NAAQS or are contributing to a violation of the 2008 ozone NAAQS within this preliminary nonattainment area: Ashtabula; Cuyahoga; Geauga; Lake; Lorain; Medina; Portage; and, Summit.

Table 15 summarizes which factors discussed above support the inclusion of each Ohio county in the preliminary nonattainment area for the 2008 ozone NAAQS.

**Table 15. Factors Supporting Inclu sion of Ohio Counties in the**  **Cleveland**

**- Akron** 

**- Elyria, OH 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** 
**Favor s**  **High Ozone**

**or Emissions**  **Impact on Violating** 

**Monitor Jurisdictional**  **Basis for Inclusion In**  **Nonattainment**
**Area**

Ashtabula X X X NA X Cuyahoga X X NA X Geauga X X NA X Lake X X X NA X Lorain X X NA X Medina X X NA X Portage X X NA X Summit X X NA X

The results in the above table show that all counties in the Cleveland

- Akron

- Elyria, OH CSA should be included in the Cleveland

- Akron

- Elyria, OH nonattainment area for the 2008 ozone NAAQS. Ashtabula, Geauga, and Lake Counties have monitored viola tions of the 2008 ozone NAAQS. All counties, except Geauga County, have high emissions or emissions

- related data (population, population growth, and/or traffic levels) that support inclusion in the nonattainment area. Finally, all of these counties are r ecommended for inclusion in the ozone nonattainment area by the State of Ohio and were included in the ozone nonattainment area for the 1997 ozone NAAQS.31 Based on these factors, we conclude that the entire Cleveland

Akron

- Elyria, OH CSA should be included in the Cleveland

- Akron

Elyria, OH nonattainment area for the 2008 ozone NAAQS.

**Technical Analysis for Columbus**

**- Marion** 

**- Chillicothe, OH** 

Figure 3 is a map of the intended Columbus, OH ozone nonattainment area for the 2008 ozone NAAQS. The map provides oth er relevant information, including the locations and ozone design values of air quality monitors recording violations of the 2008 ozone NAAQS, county and other jurisdictional boundaries, existing maintenance boundary for the 1997 ozone NAAQS, Columbus

- Mari on

- Chillicothe, OH CSA boundary and major transportation arteries.

**Figure 3. Columbus**

**- Marion** 

**- Chillicothe, OH Area** 

For purposes of the 1997 ozone NAAQS, as noted in Figure 3, portions of this area were designated nonattainment and subsequently redesign ated to attainment (maintenance). The32 boundary for the nonattainment area for the 1997 ozone NAAQS included only a portion of the Columbus

- Marion

- Chillicothe, OH CSA. In March 2009, Ohio recommended that the same counties (the same counties included in t he nonattainment area for the 1997 ozone NAAQS) in Ohio be designated as nonattainment for the 2008 ozone NAAQS based on air quality data from 2006

- 2008 and other considerations. The 2006

- 2008 ozone data are from 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 the same 6 counties in Ohio (identified in Table 16 below) as “nonattainment” for the 2008 ozone NAAQS as part of the Columbus, OH nonattainment area.

**Table 16. EPA’s Intended Designated Nonattainment Counties for the Columbus, OH Ozone Nonattainment Area** 

**State**

**- Recommended Nonattainment**  **Counties in Ohio EPA Intended Nonattainment Counties**  **in Ohio** Delaware Fairfiel d Franklin
Knox Licking Madison Delaware Fairfield Franklin
Knox Licking Madison

**Factor Assessment**

**Factor 1: Air Quality Data**

For this factor, we considered 8

- hour ozone design values (in ppm) for air quality monitors in counties in the Columbus

Mario n

- Chillicothe, OH CSA based on data for the 2008

- 2010 period, which are the most recent years with fully

- certified air quality data. As discussed above, a monitor’s design value is the metric or statistic that indicates whether that monitor attains a spec ified air quality standard. The 2008 ozone NAAQS are met at a monitor when the annual fourth

- highest daily maximum 8

- hour ozone concentrations, averaged over 3 years is 0.075 ppm or less. A design value is valid only if minimum data completeness requirem ents are met. See 40 CFR part 50 Appendix P. Where several monitors are located in a county or area (or a designated nonattainment area or maintenanc e area ) , the design value for the county or area is determined by the monitor with the highest individual design value.

The ozone design values for ozone monitors in the Columbus

Marion

- Chillicothe, OH CSA are shown in Table 17.33 **Table 17. Ozone Air Quality Data for the Columbus**

**- Marion** 

**** **Chillicothe, OH CSA**

**State/County Site Number**  **2008**

**- 2010**  **8**

**- Hour**  **Ozone**
**Des ign**  **Values**

**(ppm)** Delaware 390410002 0.073 Franklin 390490081 0.069 Franklin 390490037 0.071 Franklin 390490029 **0.078 †** 
Knox 390830002 0.071 Licking 390890005 0.072 Madison 390970007 0.070 **†** Monitored violation of the 2008 ozone NAAQS.

From Table 1 7, it can be seen that Franklin County is the only county in the Columbus

- Marion

- Chillicothe, OH CSA with a monitored violation of the 2008 ozone NAAQS for the period of 2008

- 2010. Therefore, at minimum, Franklin County must be included in the ozone nonat tainment area. As note d above, a county (or partial county) must also be designated nonattainment if it contributes to an air quality violation in a nearby area (to the violation of the 2008 ozone NAAQS recorded in Franklin County). Each county in the Co lumbus

- Marion

- Chillicothe, OH CSA has been evaluated, as discuss ed below, based on the five factors discussed above and other relevant information to determine whether it contributed to the violation of the 2008 ozone NAAQS in Franklin County.

Please not e that the State of Ohio, in its March 9, 2009 area designation recommendations and accompanying technical support documentation, based its area recommendations on 2006

- 2008 ozone data. Since these data no longer cover the most recent 3

- year period with q uality

- assured, state

- certified data and have been supplanted by the more current 2008

- 2010 ozone data, we are not reviewing the older ozone data covered by the state of Ohio.

**Factor 2: Emissions and Emissions**

**- Related Data** 

EPA evaluated emissions for VO C and NOx and other emissions

related data (primarily county population, population density, and traffic levels, and projected growth rates for these emissions

- related data) that provide information on area contributions to local ozone standard violations.34 **EPA’s Accumulated Emissions and Emissions**

**- Related Data**  **Emissions Data**

EPA evaluated county

- level emission data for NOx and VOC derived from the 2008 NEI, version 1.5. These are the most recently available NEI emissions data. (See http://www.epa.gov/ttn/chief/net/2008inventory.html ) Significant emission levels in a nearby area (in a county near to a county with a violating ozone monitor) indicate the potential for the area to contribu te to the observed ozone standard violation.

Table 18 shows the 2008 emissions of NOx and VOC (in tons per year) for all counties in the Columbus

- Marion

- Chillicothe, OH CSA. This table also indicates which of the counties were recommended to be nonatta inment for the 2008 ozone NAAQS by the State of Ohio.

**Table 18. Total 2008 VOC and NOx Emissions (tons/year) in the Cleveland** 

**- Akron** 

**- Elyria, OH CSA** 

**State/County State Recommended**  **Nonattainment? VOC Emissions**  **(tpy) NOx Emissions**  **(tpy)** Ohio: Delaware Yes 5,686 5,655 Fairfield Yes 4,459 4,915 Fayette No 1,887 1,981 Franklin Yes 38,690 32,092
Knox Yes 2,324 1,539 Licking Yes 7,016 6,008 Madison Yes 2,373 2,809 Marion No 3,588 3,509
Morrow No 1,983 2,190 Pickaway No 2,969 3,919
Ross No 3,292 5,010 Union No 3,404 2,413 **CSA Total** 77,671 72,041

From the emissions data in Table 18, it can be seen that the VOC and NOx emissions in the Columbus

- Marion

- Chillicothe, OH CSA are dominated by those in Franklin County. The VOC emissions in Franklin County are 49.8 percent of the CSA total, and the NOx emissions in Franklin County are 44.5 percent of the CSA total. All other counties in this CSA have significantly lower and similar (to each other) VOC and NOx emissions. However, the accumulative VOC and N Ox emissions in these remaining counties is a significant portion of the total VOC and NOx emissions in the CSA.35 The high emissions in Franklin County, along with the monitored violation of the 2008 ozone NAAQS in this county, implies that Franklin Count y should be part of the nonattainment area for the 2008 ozone NAAQS. The VOC and NOx emissions for the remaining counties in the Columbus

- Marion

- Chillicothe , OH CSA do not provide a definitive basis for inclusion or exclusion from the nonattainment area. Note that the counties Ohio is recommending for exclusion from the nonattainment area have similar VOC and NOx emissions to many of the Ohio

- reco mmended nonattainment counties in the Columbus

- Marion

- Chillicothe, OH CSA

.
**Population, Population Density, an d 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 emission s from on

- road and off

- r oad 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, which can contribute to local and downwind high ozone concentrations. Rapid population or VMT growth in a county on the urban perimeter signifies increasing integration with the urban core area, and indicates that it may be appropriate to include this county in the ozone nonattainment

ar ea, particularly if this county already has moderate or higher VOC and/or NOx emissions.

Table 19 shows the 2010 population, population density, and population growth information for each county in the Columbus

Marion

- Chillicothe, OH CSA.

**Table 19. Popu lation and Population Growth in the Columbus** 

**** **Marion**

**- Chillicothe, OH 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)** 

O hio: Delaware Yes 174,214 0.38 62,504 56 Fairfield Yes 146,156 0.29 22,736 18 Fayette No 29,030 0.07 595 2 Franklin Yes 1,163,414 2.14 91,127 8
Knox Yes 60,921 0.12 6,278 11 Licking Yes 166,492 0.24 20,421 14 Madison Yes 43,435 0.09 3,223 836 Marion No 66,501 0.16 351 1
Morrow No 34,827 0.09 3,033 10 Pickaway No 55,698 0.11 2,882 5
Ross No 78,064 0.11 4,614 6 Union No 52.300 0.12 11,105 27 CSA Totals 2,071,052 0.34 228,869 12 Sources: U.S. Census Bureau population estimates for 2010 as of Augus t 4, 2011. ( http://factfinder2.census.gov/faces/tableservices/jsf/pages/pro ductview.xhtml?pid=DEC_10_PL_GCTPL2.STO5&proTyp e=table )

The population data show that half of the 2010 population and almost half of the 2000

- 2010 population growth in the Columbus

Marion

- Chillicothe, OH CSA can be fou nd in Franklin County. Comparatively large 2010 populations and 2000

- 2010 populati on growths can also be found in Delaware, Fairfield, and Licking Counties. The 2010 populations in the remaining count ies in the CSA are comparatively smaller. Union County has a comparativley high population growth percentage, however, it s 2010 populati on is small compared to those of Delaware, Fairfield, Franklin, and Licking Counties. Finally, the 2010 populations and 2000

- 2010 population growths of Fayette and M arion Counties are comparatively lower than those of other counties in the Columbus

- Marion

- Chillicothe, OH CSA.

**Traffic and Commuting Patterns**

EPA evaluated the commuting patterns of residents in the Columbus

- Marion

- Chillicot he, OH CSA . In combination with the county

- specific population/population density data and the locations of the main t ransportation arteries (see above), this information helps identify the probable locations of non

- point source emissions. A county with high VMT and/or a high number of commuters is generally an integral part of an urban area and indicates the presence of relatively high motor vehicle emissions that may significantly contribute to ozone standard violations in or downwind of the urban area. Rapid population or VMT growth in a county on the urban perimeter signifies increasing integration with the urban cor e area, and indicates that this county should be included in the ozone nonattainment area, particularly if the VOC and/or NOx emissions in this county are a significant portion of the total emissions in the nonattainment area.

Table 20 shows the traffic l evels, 2008 VMT, in each county in the Columbus

- Marion

- Chillicothe, OH CSA.37 **Table 20. Traffic Levels in the Columbus**

**- Marion** 

**- Chillicothe, OH** 
**CSA State/County**  **State Recommended Nonattainment?**  **2008 VMT (million miles)**

Ohio: Delaware Yes 1,530 Fairfield Y es 1,035 Fayette No 505 Franklin Yes 10,645
Knox Yes 397 Licking Yes 1,780 Madison Yes 704 Marion No 629
Morrow No 605 Pickaway No 648
Ross No 772 Union No 630 CSA Total 19,881

The VMT data show that county

- specific VMT levels are the highest in Delaware, Franklin, Fairfield, and Licking Counties. These VMT account for 75.4 percent of the total VMT in the Columbus

- Marion

- Chillicothe, OH CSA.

The VMT data plus the population data in Table 19 indicate that Delaware, Fairfield, Franklin, and L icking Counti es are relatively urbanized with significant population

- and traffic

related emissions that contributed to the ozone standard violation in Fr anklin County. This contribution is much smaller for the remaining counties in the Columbus

- Marion

- Ch illicothe,
OH CSA.

**Additional Emissions**

**- Related Data Discussed in Ohio’s March 9,**  **2009 Designation Recommendation Submittal**

OEPA has provided typical daily, county

- specific total VOC and NOx emissions for 2005 and 2009 for each of the counties in the Col umbus

- Marion

- Chillicothe, OH CSA. These data confirm the conclusions we have drawn above using county

- specific annual emissions.

OEPA has provided population projections through 2030 for each of the counties in the CSA. Populations are projected to inc rease significantly in Delaware, Fairfield, Franklin, Licking, Medina, Morrow, Pickaway, Ross, and Union Counties. Populations are projected to increase moderately in Fayette and Marion Counties. Populations are expected to decline in Knox County.38 OEPA provided graphs of daily VMT levels plotted for the period of 1990

- 2007 for each of the counties in the CSA. This visual VMT trend information shows that daily VMT grew significantly during the 1990

- 2007 period for Delaware, Fairfield, Franklin, Licking a nd Morrow Counties. The VMT trend information shows that daily VMT grew moderately during the 1990

- 2007 period for Knox, Marion, Pickaway (VMT levels remained substantially unchanged after 1999 in this county), and Ross Counties.

OEPA provided inter

- coun ty commuter numbers and percentages for each of the counties in the Columbus

- Marion

- Chillicothe, OH CSA. These numbers show a moderate to high inter

- county commuting pattern between Franklin County and other counties (with the exceptions of Fayette, Knox, Ross, Marion, and Morrow Counties) in the Columbus

- Marion

- Chillicothe, OH CSA. Inter

- county commuter numbers between other counties (other than Franklin County) in the CSA are moderate to small.

Collectively, the OEPA

- supplied population and traffic/commuter data show moderate integration between Franklin, Delaware, Fairfield, Licking, Medina, Morrow, Pickaway, Ross, and Union Counties. Less integration is apparent between Franklin, Fayette, Knox, and Marion Counties. This implies that, from an emissio ns standpoint, the Columbus, OH ozone nonattainment area should include Delaware, Fairfield, Franklin, Licking, Medina, Morrow, Pickaway, Ross, and Union Counties. Remaining counties in the CSA could be excluded on the basis that their emissions
are not s ignificant contributors to the monitored violations of the 2008 ozone NAAQS in Franklin County.

**Factor 3: Meteorology (Weather/Transport Patterns)**

**EPA’s Accumulated Meteorological Data**

EPA evaluated available meteorological data to help determine how m eteorological conditions, particularly transport conditions, affect the fate and transport of ozone and ozone precursors contributing to ozone formation in the Columbus

Mario

- Chillicothe, OH CSA. EPA examined the frequency distribution of wind directions for the four seasons of the year by averaging National Weather Service direction

- sorted wind directions for each county for a 30

- year period

**.** To apply the results of this data analysis to the Columbus

- Marion

Chillicothe, OH CSA, we have considered the win d direction (direction from which winds are blowing, reflecting directions to potential source areas) frequencies during the summer months (June

- August) for Franklin County, which is the only county in39 the CSA with a monitored violation of the 2008 ozone N AAQS (See Table 17).

Table 21 shows the summertime 30

- year averaged percentages of wind directions (winds blowing into the subject county from the specified wind direction sector) for Franklin County.

**Table 21. Averaged Summertime Wind Direction Perce ntages For**  **Franklin County**

**Wind Direction Franklin County**  North

- Northeast 15.3
East

- Northeast 9.6
East

- Southeast 11.4 South

- Southeast 12.0 South

- Southwest 22.0
West

- Southwest 11.0
West

- Northwest 9.7 North

- Northwest 9.0

The wind direction percent ages show that there is no single “preferred” wind direction during the summertime, when the highest ozone concentrations are generally monitored. Winds from south

- southwest may be more prevalent than the winds from other wind directions during the summer time.

Unfortunately, EPA’s wind direction percentage data do little to shed light on which counties in the Columbus

- Marion

- Chillicothe, OH CSA are the most important from an ozone and ozone precursor transport standpoint. The wind directions considered h ave not been sorted based on peak ozone concentrations or specifically for high ozone days, the timing of peak ozone concentrations, wind speeds, or other factors that could have been used to isolate the most critical ozone precursor source areas.

**Facto r 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 Columbus

- M arion

- Chillicothe, OH CSA 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.

**Factor 5: Jurisdictional Bo undaries** 40 Once we identified the general area that we anticipated we would recommend as nonattainment for the 2008 ozone NAAQS, we then considered existing jurisdictional boundaries for the purposes of providing a clearly defined legal boundary and to help identify the area appropriate for carrying out the air quality planning and enforcement functions for an ozone nonattainment area. Examples of jurisdictional boundaries include existing/prior nonattainment boundaries for ozone or other urban

- scale pollut ants, county boundaries, air district boundaries, township boundaries, areas covered by metropolitan planning organizations, state lines, and Reservation boundaries. Where existing jurisdictional boundaries are not adequate or appropriate to describe the nonattainment area, other clearly defined and permanent landmarks or geographic coordinates may be considered.

The portion of the Columbus

- Marion

- Chillicothe, OH CSA that w e are considering for designation as nonattainment for the 2008 ozone NAAQS has a p reviously established nonattainment boundary associated with the 1997 8

- hour ozone NAAQS. The State of Ohio has recommended the same counties (as included in the 1997 8

- hour ozone nonattainment area) in Ohio be included in the boundary of the nonattainmen t area for the 2008 ozone NAAQS. The prior inclusion of these counties in the ozone nonattainment area for the 1997 ozone NAAQS forms the primary jurisdictional basis for the inclusion of these counties in the nonattainment area for the 2008 ozone NAAQS.

**Conclusion**

Based on the assessment of factors described above, EPA has preliminarily concluded that the following Ohio counties should be included in the Columbus, OH ozone nonattainment area because they are either violating the 2008 ozone NAAQS or are contributing to a violation of the 2008 ozo ne NAAQS within this intended ozone nonattainment area: Delaware; Fairfield; Franklin; Knox; Licking; and, Madison.

Table 22 summarizes which factors discussed above support the inclusion of each Ohio county in t he Columbus, OH preliminary nonattainment area for the 2008 ozone NAAQS.

**Table 22. Factors Supporting Inclusion of Ohio Counties in the Columbus, OH Ozone Nonattainment Area for the 2008 Ozone NAAQS** 

**County Violates**  **High Meteorology**  **Geography Jurisdictional** 41 **Ozone Standard**  **Emissions Populati**  **on and Traffic**  **Levels Favors**  **Emissions Impact on**  **Violating**

**Monitor Favors**  **High Ozone**

**or Emissions**  **Impact on Violating** 

**Monitor Basis for**  **Inclusion In Nonattainment** 
**Area**

Delaware X X NA X Fairfield X X NA X Frankli n X X X NA X
Knox X NA X Licking X X NA X Madison X NA X

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 th e 2008 ozone NAAQS and/or significant 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 emission s, populations, and traffic levels 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 no nattainment 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.