Document ID: EPA-HQ-OAR-2007-0562-0429
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2009-11-13T05:00Z

Attachment 1

Ohio Area Designations For the 

24-Hour Fine Particle National Ambient Air Quality Standard

The table below identifies the counties in Ohio that EPA has designated
as not attaining the 2006 24-hour fine particle (PM2.5) standard.  A
county or part thereof is designated as nonattainment if it has an air
quality monitor that is violating the standard or if the county is
determined to be contributing to the violation of the standard.

 

Area 	Ohio Recommended Nonattainment Counties	EPA’s Designated
Nonattainment Counties

Canton-Massillon, OH	Stark	Stark

Cincinnati- Hamilton, OH- KY-IN	Butler

Clermont

Hamilton

Warren	Butler

Clermont

Hamilton

Warren

Cleveland- Akron-Lorain, OH	Cuyahoga

Lake

Lorain

Medina

Portage

Summit	Cuyahoga

Lake

Lorain

Medina

Portage

Summit

Columbus, OH	Delaware

Fairfield

Franklin

Licking	Delaware

Fairfield

Franklin

Licking

Coshocton (partial)*

Dayton- Springfield, OH	Greene

Montgomery	Clark

Greene

Montgomery

Huntington- Ashland, WV- KY-OH	None 	Adams (partial)* 

Gallia (partial)*

Lawrence

Scioto

Parkersburg- Marietta, WV- OH	Washington	Washington

Steubenville- Weirton, OH- WV	Jefferson	Jefferson

Youngstown- Warren, OH	Mahoning

Trumbull	Mahoning

Trumbull

EPA is designating the remaining counties and portions of counties in
the state as “attainment/unclassifiable.”  

*EPA is including the following portions of the noted counties in the
respective nonattainment area:

Coshocton County – Franklin Township

Adams County – Monroe and Sprigg Townships

Gallia County – Cheshire Township

EPA Technical Analysis for Canton-Massillon, OH 

In the Canton area, Stark County is designated nonattainment for the
1997 PM2.5 standards.  A monitor in Stark County is recording violations
of the 2006 standards.  Ohio recommended that the Canton nonattainment
area consist of Stark County.

EPA concurs with the state’s recommendation.  Although Canton is near
the Cleveland, Steubenville, and Youngstown areas, these areas are all
separate metropolitan areas, and EPA believes that the four metropolitan
areas are sufficiently distinct to warrant treatment as four separate
nonattainment areas.  Within the Canton metropolitan statistical area,
Stark County sources emit about 90 percent of the emissions in this
area.  In addition, establishing nonattainment boundaries that match the
boundaries established for the 1997 standards will simplify planning by
assuring that the same areas are subject very similar nonattainment
planning requirements.

In general, the only surrounding counties with emissions comparable to
the emissions of Stark County are in either the Steubenville, Cleveland,
or Youngstown areas, and no other factor warranted inclusion of any
county other than Stark County in the Canton nonattainment area.

Figure 1 is a map of the counties in the nonattainment area and other
relevant information such as the locations and design values of air
quality monitors, and the metropolitan area boundary. 

 

Figure 1

For this area, EPA previously established PM2.5 nonattainment boundaries
for the 1997 PM2.5 NAAQS that included one county.  

In its December 17, 2007 letter, Ohio recommended the same county in the
Canton area be designated as “nonattainment” for the 2006 24-hour
PM2.5 standard based on air quality data from 2004-2006.  These data are
from Federal Reference Method (FRM) monitors located in the state.

In August 2008, EPA notified Ohio of its intended designations.  In this
letter, EPA also requested that if the State wished to provide comments
on EPA’s intended designation, it should do so by October 20, 2008. 
EPA stated that it would consider any additional information (e.g., on
power plants or partial county areas) provided by the state in making
final decisions on the designations.  

Based on EPA's technical analysis described below, EPA designated one
county, Stark County, Ohio as nonattainment for the 24-hour PM2.5
air-quality standard as the Canton nonattainment area, based upon
currently available information.

The following is a review of data for relevant factors for the Canton,
Ohio area. 

Factor 1:  Emissions data

For this factor, EPA evaluated county level emission data for the
following PM2.5 components and precursor pollutants:  “PM2.5 emissions
total,” “PM2.5 emissions carbon,” “PM2.5 emissions other,”
“SO2,” “NOx,” “VOCs,” and “NH3.”  “PM2.5 emissions
total” represents direct emissions of PM2.5 and includes: “PM2.5
emissions carbon,” “PM2.5 emissions other”, primary sulfate (SO4),
and primary nitrate.  (Although primary sulfate and primary nitrate,
which are emitted directly from stacks rather than forming in
atmospheric reactions with SO2 and NOx, are part of “PM2.5 emissions
total,” they are not shown in Table 1 as separate items).  “PM2.5
emissions carbon” represents the sum of organic carbon (OC) and
elemental carbon (EC) emissions, and “PM2.5 emissions other”
represents other inorganic particles (crustal).  Emissions of SO2 and
NOx, which are precursors of the secondary PM2.5 components sulfate and
nitrate, are also considered.  VOCs (volatile organic compounds) and NH3
(ammonia) are also potential PM2.5 precursors and are included for
consideration. 

Emissions data were derived from the 2005 National Emissions Inventory
(NEI), version 1.  See
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

EPA also considered the Contributing Emissions Score (CES) for each
county.  The CES is a metric that takes into consideration emissions
data, meteorological data, and air quality monitoring information to
provide a relative ranking of counties in and near an area.  Note that
this metric is not the exclusive manner for considering data for these
factors.  A more detailed description can be found at
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html#C.

Table 1 shows emissions of PM2.5 and precursor pollutants components
(given in tons per year) and the CES for violating and potentially
contributing counties in the Canton area.  Counties that are part of the
Canton nonattainment area for the 1997 PM2.5 NAAQS are shown in
boldface.  Counties are listed in descending order by CES.

Table 1.  PM2.5 24-hour Component Emissions, and CESs 

County	State Recommended Nonattainment?	CES	PM2.5

emissions 

total	PM2.5

emissions 

carbon	PM2.5

emissions 

other	SO2

	NOx

	VOCs

	NH3

Jefferson, OH	Other	100	11,409	722	10,686	224,025	46,158	3,693	297

Stark, OH	Yes	11	1,488	574	915	2,334	13,046	19,011	1,902

Summit, OH	Other	11	1,031	576	454	12,545	17,359	21,753	923

Tuscarawas, OH	No	5	636	295	342	2,890	4,919	5,477	1,238

Wayne, OH	No	5	1,408	468	938	4,812	7,546	6,934	3,702

Portage, OH	Other	2	1,011	496	514	548	7,269	8,365	564

Carroll, OH	No	1	338	141	196	123	1,627	1,482	409

Jefferson and Summit Counties have high emission.  Jefferson County is
part of the Steubenville nonattainment area for the 1997 PM2.5 NAAQS. 
Summit and Portage Counties are part of the Cleveland nonattainment area
for the 1997 PM2.5 NAAQS.  EPA feels these counties remain a part of the
Steubenville and Cleveland areas.  Stark County is the only remaining
county with high emissions.  The other counties not in other areas all
have modest emissions.

 

Table 2 provides the data for CES weighting factors.  The trajectory
factors are used in CES calculations to account for seasonal
meteorology.  For the top 10% of days in both the cold and warm seasons,
wind trajectories were run for a 48 hour period preceding the high
monitor reading.  The amount of time the air mass was over a county
within the mixing height was calculated.  The values were scaled so that
the maximum value is 100.  Thus, the county that is most likely to be
upwind of a monitor on a high concentration day in a season is given a
score of 100.  The scores for the other counties will reflect the
relative likelihood of being upwind.  As the concentration of a
pollutant will decrease as it goes further downwind, a distance
weighting factor is also used in calculating the CES.  The distance
factor listed on Table 2 provides the distance from the center of a
county to the center of the violating county.  If a county is violating,
the distance used is the average distance from the center to the county
line.

  Table 2.  CES Factor Data

County	CES	Trajectory Factor- Cold	Trajectory Factor- Warm	Distance (mi)

Jefferson	100	55	57	44.5

Stark	11	100	83	13.3

Summit	11	69	46	23.7

Tuscarawas	5	96	100	26.5

Wayne	5	84	53	27.3

Portage	2	57	42	26.2

Carroll	1	88	83	21.7

Factor 2:  Air quality data 

This factor considers the 24-hour PM2.5 design values (in µg/m3) for
air quality monitors in counties in the Canton area based on data for
the 2005-2007 period.  A monitor’s design value indicates whether that
monitor attains a specified air quality standard.  The 24-hour PM2.5
standards are met when the 3-year average of a monitor’s 98th
percentile values are 35 µg/m3 or less.  A design value is only valid
if minimum data completeness criteria are met.

The 24-hour PM2.5 design values for counties in the Canton area are
shown in Table 3.

Table 3.  Air Quality Data

County	State 

Recommended

 Nonattainment?	Design Values

2004-06

(µg/m3)

	Design Values

2005-07

(µg/m3)

Stark, OH	Yes	37	36

Jefferson, OH	Other	43	40

Summit, OH	Other	38	37

Tuscarawas, OH	No

Wayne, OH	No

Portage, OH	Other	34	35

Carroll, OH	No

Stark County has a design value exceeding the air quality standard. 
Jefferson and Summit also exceed the standards, but are in other
nonattinment areas.  Other area counties do not have monitoring data. 
However, the absence of a violating monitor alone does not eliminate
counties from nonattainment status.  Each county has been evaluated
based on the weight of evidence of the nine factors and other relevant
information.

For purposes of its review, EPA used data available from the Chemical
Speciation Network and the Interagency Monitoring of Protected Visual
Environments (IMPROVE) network to estimate the composition of fine
particle mass on days with the highest fine particle concentrations. 
Analysis of these data indicates that the days with the highest fine
particle concentrations in the Canton area occur about 83% in the warm
season and 17% in the cool season.  In the warm season, the average
chemical composition of the highest days is 78% sulfate, no nitrate, 19%
carbon, and 3% crustal.  In the cool season, the average chemical
composition of the highest days is 34% sulfate, 30% nitrate, 33% carbon,
and 3% crustal.  These data indicate that sources of SO2, NOx, and
direct PM2.5 emissions contribute to violations in the area.

Factor 3: Population density and degree of urbanization (including
commercial development)

Table 4 shows the 2005 population for each county in the area being
evaluated, as well as the population density for each county in that
area.  Population data gives an indication of whether it is likely that
population-based emissions might contribute to violations of the 24-hour
PM2.5 standards. 

Table 4.  Population

County	State Recommended Nonattainment?	2005 Population	2005 Population
Density 

(pop/sq mi)

Stark, OH	Yes	380,275	655

Jefferson, OH	Other	70,631	172

Summit, OH	Other	546,285	1302

Tuscarawas, OH	No	91,791	161

Wayne, OH	No	113,496	204

Portage, OH	Other	155,150	307

Carroll, OH	No	29,252	73

The Stark County population and population density are much higher than
Carroll Counties.  Aside from counties included in other nonattainment
areas, Stark County is larger than other nearby counties.  Thus, the
population data suggest that Stark County is a good candidate for
inclusion in the nonattainment area.

Factor 4: Traffic and commuting patterns 

This factor considers the number of commuters in each county who drive
to another county within the Canton area, the percent of total commuters
in each county who commute within the area, as well as the total Vehicle
Miles Traveled (VMT) for each county in millions of miles (see Table 5).
 A county with numerous commuters is generally an integral part of an
urban area and is likely contributing to fine particle concentrations in
the area.  

Table 5.  Traffic and Commuting Patterns

County	State Recommended Nonattainment?	2005 VMT

(106 mi)	Number Commuting to any violating counties 	Percent

Commuting to any violating counties 	Number Commuting into statistical
area 	Percent

Commuting into statistical area 

Stark, OH	Yes	     3,049 	162,800 	92 	    141,490 	          80 

Jefferson, OH	Other	        684 	20,090 	70 	           460 	           
2 

Summit, OH	Other	     4,929 	201,840 	78 	        7,670 	            3 

Tuscarawas, OH	No	     1,122 	6,360 	15 	        6,000 	          14 

Wayne, OH	No	     1,044 	5,640 	10 	        1,670 	            3 

Portage, OH	Other	     1,788 	21,230 	27 	        1,580 	            2 

Carroll, OH	No	        173 	5,620 	44 	      10,660 	          83 

Mahoning, OH	Other	    2,666 	80,330 	74 	        2,590 	            2 

The listing of counties on Table 5 reflects a ranking based on the
number of people commuting within the Canton area.  The county that is
in the Canton nonattainment area for the 1997 PM2.5 NAAQS is shown in
boldface.  There is very limited commuting from Jefferson, Mahoning,
Portage, and Summit Counties into the Canton area.  This suggests these
counties are not a part of the Canton area, but they are a part of
separate areas instead.  The Carroll County VMT is small.  Thus, the
commuting data support including only Stark County in the nonattainment
area.

Note:  The 2005 VMT data used for tables 5 and 6 of the technical
analysis have been derived using methodology such as that described in
"Documentation for the 2005 Mobile National Emissions Inventory, Version
2," December 2008, prepared for the Emission Inventory Group, U.S. EPA. 
This document may be found at:   HYPERLINK
"ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/20
05_mobile_nei_version_2_report.pdf" 
ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/200
5_mobile_nei_version_2_report.pdf .

Factor 5:  Growth rates and patterns  

This factor considers population growth for 2000-2005 and growth in
vehicle miles traveled for 1996-2005 for counties in Canton area, as
well as patterns of population and VMT growth.  A county with rapid
population or VMT growth is generally an integral part of an urban area
and likely to be contributing to fine particle concentrations in the
area.

Table 6 below shows population, population growth, VMT, and VMT growth
for counties that are included in the Canton area.  Counties are listed
in descending order based on VMT growth between 1996 and 2005.

Table 6.  Population and VMT Growth and Percent Change.

County	Population (2005)	Population % change (2000-2005)	2005 VMT

(106 mi)	VMT % change 

(1996-2005)

Tuscarawas, OH	      91,791 	1 	     1,122 	            6 

Wayne, OH	    113,496 	2 	     1,044 	            6 

Portage, OH	    155,150 	2 	     1,788 	            6 

Summit, OH	    546,285 	0 	     4,929 	            1 

Stark, OH	    380,275 	1 	     3,049 	           -1

Carroll, OH	      29,252 	1 	        173 	           -1

Jefferson, OH	      70,631 	-4	        684 	           -6

There is little growth in the Canton area and surrounding counties.  VMT
declined slightly in both Carroll and Stark Counties, while their
population grew slightly.  Thus, these data do not suggest trends in
population of VMT that should influence the nonattainment area
boundaries.

Factor 6:  Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service
instruments and other meteorological monitoring sites in the area.  Wind
direction and wind speed data for 2005-2007 were analyzed, with an
emphasis on “high PM2.5 days” for each of two seasons, an
October-April “cold” season and a May-September “warm” season. 
These high days are defined as days where any FRM or FEM air quality
monitors had 24-hour PM2.5 concentrations above 95% on a frequency
distribution curve of PM2.5 24-hour values. 

μg/m3 are denoted with a red or black icon.  A dot indicates the day
occurred in the warm season; a triangle indicates the day occurred in
the cool season.  The center of the figure indicates the location of the
air quality monitoring site, and the location of the icon in relation to
the center indicates the direction from which the wind was blowing on
that day.  An icon that is close to the center indicates a low average
wind speed on that day.  Higher wind speeds are indicated when the icon
is further away from the center.

The pollution rose for the Canton area is provided as Figure 2.  Winds
on high concentration days come from a variety of directions.  So, it is
appropriate to include counties in all directions from the violations.

  

Figure 2

Note:  the meteorology factor is also considered in each county’s
Contributing Emissions Score because the method for deriving this metric
included an analysis of trajectories of air masses for high PM2.5 days.

Factor 7:  Geography/topography (mountain ranges or other air basin
boundaries)

The geography/topography analysis evaluates the physical features of the
land that might have an effect on the air shed and, therefore, on the
distribution of PM2.5 over the area.

The Canton 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 the
decision-making process.

Factor 8:  Jurisdictional boundaries

In evaluating the jurisdictional boundary factor, EPA gave special
consideration to areas that were already designated nonattainment in
2005 for violating the 1997 fine particle standards.  Analysis of
chemical composition data in these areas indicates that the same
components that make up most of the PM2.5 mass in the area on an annual
average basis such as sulfate and direct PM2.5 carbon in many eastern
areas also are key contributors to the PM2.5 mass on days exceeding the
24-hour PM2.5 standard.  These data indicate that in many cities, the
same source categories that contribute to violations of the annual
standard also contribute to exceedances of the 24-hour standard.  

EPA has generally concluded that counties that were designated as having
emissions sources contributing to fine particle concentrations which
exceeded the 1997 standards (all areas violated the annual standard, two
also violated the previous 24-hour standard) also contribute to fine
particle concentrations on the highest days.  For this reason, EPA
believes that for most existing nonattainment areas, the nonattainment
area for the 2006 24-hour standard should be the same.  Consideration
also should be given to existing boundaries and organizations as they
may facilitate air quality planning and the implementation of control
measures to attain the standard.  Areas already designated as
nonattainment represent important boundaries for state air quality
planning.

The Northeast Ohio Area wide Coordinating Agency is the Metropolitan
Planning Organization (MPO) for the Cleveland area.  It includes
Cuyahoga, Geauga, Lake (Ohio), Lorain, and Medina Counties.  The
Eastgate Regional Council of Governments is the Youngstown MPO including
Mahoning and Trumbull Counties in Ohio.

Factor 9:  Level of control of emission sources 

Under this factor, the existing level of control of emission sources is
taken into consideration.  The emissions data used by EPA in this
technical analysis and provided in Table 1 under Factor 1 represent
emissions levels taking into account any control strategies implemented
in the Canton area before 2005 on stationary, mobile, and area sources. 
Data are presented for PM2.5 components that are directly emitted,
carbonaceous PM2.5 and crustal PM2.5, and for pollutants which react in
the atmosphere to form fine particles such as SO2, NOx, VOC, and
ammonia.  

In considering county-level emissions, EPA used data from the 2005
National Emissions Inventory, the most updated version of the national
inventory available at the beginning of the designations process in late
2007.  However, EPA recognized that for certain counties, emissions may
have changed since 2005.  For example, certain power plants or large
sources of emissions in or near this area may have installed emission
controls or otherwise significantly reduced emissions since 2005.  Some
States provided updated information on emissions and emission controls
in their comments to EPA.  EPA considered such additional information in
making final designation decisions.  

With regard to nearby power plants, EPA considered information about
whether a specific plant installed federally enforceable emission
controls by December 2008 resulting in significant emissions reductions.
 A control requirement is considered to be federally-enforceable if it
is required by a State regulation adopted in a State implementation
plan, if it is included in a federally-enforceable Title V operating
permit, or if it is required by a consent decree which also requires the
controls to be included in federally enforceable permit upon termination
of the consent decree.  In making final decisions, EPA also considered
whether a facility would continue to emit pollutants which contribute to
PM2.5 exceedances even after emission controls are operational. 

Ohio did not provide other information regarding power plants or any
other large sources in the Canton area.

EPA Technical Analysis for Cincinnati, Ohio 

In the three-state Cincinnati area, part or all of eight counties are
designated nonattainment for the 1997 standards.  The four Ohio counties
included in the Cincinnati nonattainment area are Butler, Clermont,
Hamilton, and Warren Counties.  Monitors in Butler and Hamilton
Counties, Ohio, and Kenton County, Kentucky, are recording violations of
the 2006 standards.  Ohio recommended that the Cincinnati nonattainment
area include the same four Ohio counties as are designated nonattainment
for the 1997 standards.

EPA concurs with the state’s recommendation.  The four Ohio counties
that Ohio recommended for nonattainment all have significant emissions
that are geographically nearby to and commonly upwind of violating
monitors.  In addition, establishing nonattainment boundaries for the
2006 standards that match the boundaries established for the 1997
standards will simplify planning by providing that all locations have
consistent nonattainment planning requirements for the two sets of
standards.  The surrounding Ohio counties have relatively low emissions,
and no other factor warrants their inclusion in the nonattainment area.

Figure 1 is a map of the counties in the nonattainment area and other
relevant information such as the locations and design values of air
quality monitors, and the metropolitan area boundary. 

 

Figure 1

For this area, EPA previously established PM2.5 nonattainment boundaries
for the 1997 PM2.5 NAAQS that included eight full and partial counties,
with four being located in Ohio.  

In its December 17, 2007 letter, Ohio recommended the same four Ohio
counties be designated as “nonattainment” for the 2006 24-hour PM2.5
standard based on air quality data from 2004-2006.  These data are from
Federal Reference Method (FRM) monitors located in the state.

In August 2008, EPA notified Ohio of its intended designations.  In this
letter, EPA also requested that if the State wished to provide comments
on EPA’s intended designation, it should do so by October 20, 2008. 
EPA stated that it would consider any additional information (e.g., on
power plants or partial county areas) provided by the state in making
final decisions on the designations.  

Based on EPA's technical analysis described below, EPA designated four
Ohio counties- Butler, Clermont, Hamilton, and Warren, and a partial
county in Indiana- Dearborn, as nonattainment for the 24-hour PM2.5
air-quality standard as part of the Cincinnati nonattainment area, based
upon currently available information.  

The following is a review of data for relevant factors for the Ohio
portion of the Cincinnati, Ohio-Kentucky-Indiana area. 

Factor 1:  Emissions data

For this factor, EPA evaluated county level emission data for the
following PM2.5 components and precursor pollutants:  “PM2.5 emissions
total,” “PM2.5 emissions carbon,” “PM2.5 emissions other,”
“SO2,” “NOx,” “VOCs,” and “NH3.”  “PM2.5 emissions
total” represents direct emissions of PM2.5 and includes: “PM2.5
emissions carbon,” “PM2.5 emissions other”, primary sulfate (SO4),
and primary nitrate.  (Although primary sulfate and primary nitrate,
which are emitted directly from stacks rather than forming in
atmospheric reactions with SO2 and NOx, are part of “PM2.5 emissions
total,” they are not shown in Table 1 as separate items).  “PM2.5
emissions carbon” represents the sum of organic carbon (OC) and
elemental carbon (EC) emissions, and “PM2.5 emissions other”
represents other inorganic particles (crustal).  Emissions of SO2 and
NOx, which are precursors of the secondary PM2.5 components sulfate and
nitrate, are also considered.  VOCs (volatile organic compounds) and NH3
(ammonia) are also potential PM2.5 precursors and are included for
consideration. 

Emissions data were derived from the 2005 National Emissions Inventory
(NEI), version 1.  See
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

EPA also considered the Contributing Emissions Score (CES) for each
county.  The CES is a metric that takes into consideration emissions
data, meteorological data, and air quality monitoring information to
provide a relative ranking of counties in and near an area.  Note that
this metric is not the exclusive manner for considering data for these
factors.  A more detailed description can be found at
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html#C.

Table 1 shows emissions of PM2.5 and precursor pollutants components
(given in tons per year) and the CES for violating and potentially
contributing counties in the Cincinnati area.  Counties that are part of
the Cincinnati nonattainment area for the 1997 PM2.5 NAAQS are shown in
boldface.  Counties are listed in descending order by CES.

Table 1.  PM2.5 24-hour Component Emissions, and CESs 

County	State Recommended Nonattainment?	CES	PM2.5

emissions 

total	PM2.5

emissions 

carbon	PM2.5

emissions 

other	SO2	NOx	VOCs	NH3

Hamilton, OH	Yes	100	6,489	1,244	5,245	88,139	50,060	38,552	2,359

Clermont, OH	Yes	36	5,399	733	4,665	90,341	35,748	6,982	407

Butler, OH	Yes	24	2,269	563	1,706	10,636	16,661	12,734	1,105

Dearborn, IN	No	22	2,780	288	2,492	47,908	12,881	3,268	229

Jefferson, IN	No	7	1,265	168	1,097	75,319	25,214	2,272	341

Boone, KY	No	6	1,629	615	1,014	5,383	10,852	5,883	286

Adams, OH	No	6	5,970	494	5,476	126,316	33,822	1,918	837

Warren, OH	Yes	5	1,304	535	768	568	7,244	7,278	792

Kenton, KY	No	3	537	269	268	1,300	6,316	5,606	266

Campbell, KY	No	2	412	179	233	731	4,231	2,923	196

The Ohio counties in the Cincinnati area all have fairly large
emissions.  Butler, Clermont, and Hamilton Counties all have high CES. 
Warren County has a lower CES, but its emissions are not insignificant. 
Adams County has significant emissions, especially sulfur dioxide, but
it is in the Huntington-Ashland area and was evaluated with that area. 

Table 2 provides the data for CES weighting factors.  The trajectory
factors are used in CES calculations to account for seasonal
meteorology.  For the top 10% of days in both the cold and warm seasons,
wind trajectories were run for a 48 hour period preceding the high
monitor reading.  The amount of time the air mass was over a county
within the mixing height was calculated.  The values were scaled so that
the maximum value is 100.  Thus, the county that is most likely to be
upwind of a monitor on a high concentration day in a season is given a
score of 100.  The scores for the other counties will reflect the
relative likelihood of being upwind.  As the concentration of a
pollutant will decrease as it goes further downwind, a distance
weighting factor is also used in calculating the CES.  The distance
factor listed on Table 2 provides the distance from the center of a
county to the center of the violating county.  If a county is violating,
the distance used is the average distance from the center to the county
line.

  Table 2.  CES Factor Data

County	CES	Trajectory Factor- Cold	Trajectory Factor- Warm	Distance (mi)

Hamilton, OH	100	100	100	10.6

Clermont, OH	36	77	71	23.2

Butler, OH	24	90	64	19

Dearborn, IN	22	73	61	21.8

Jefferson, IN	7	30	25	55.6

Boone, KY	6	77	78	16.6

Adams, OH	6	32	21	62.6

Warren, OH	5	80	57	27.4

Kenton, KY	3	79	82	15.4

Campbell, KY	2	82	84	17.4

Factor 2:  Air quality data 

This factor considers the 24-hour PM2.5 design values (in µg/m3) for
air quality monitors in counties in the Cincinnati area based on data
for the 2005-2007 period.  A monitor’s design value indicates whether
that monitor attains a specified air quality standard.  The 24-hour
PM2.5 standards are met when the 3-year average of a monitor’s 98th
percentile values are 35 µg/m3 or less.  A design value is only valid
if minimum data completeness criteria are met.

The 24-hour PM2.5 design values for counties in the Cincinnati area are
shown in Table 3.

	Table 3.  Air Quality Data

County	State

Recommended

Nonattainment?	Design Values 2004-2006

	Design Values 2005-2007

Hamilton, OH	Yes	40	41

Clermont, OH	Yes

34

Butler, OH	Yes	38	38

Dearborn, IN	No

Boone, KY	No

Warren, OH	Yes

Kenton, KY	No	35	36

Campbell, KY	No

In EPA Region 5, Hamilton and Butler Counties in Ohio show violations of
the 24-hour PM2.5 standard.  Therefore, these counties are included in
the Cincinnati nonattainment area.  However, the absence of a violating
monitor alone does not eliminate counties from nonattainment status. 
Each county has been evaluated based on the weight of evidence of the
nine factors and other relevant information.

For purposes of its review, EPA used data available from the Chemical
Speciation Network and the Interagency Monitoring of Protected Visual
Environments (IMPROVE) network to estimate the composition of fine
particle mass on days with the highest fine particle concentrations. 
Analysis of these data indicates that the days with the highest fine
particle concentrations in the Cincinnati area occur about 86% in the
warm season and 14% in the cool season.  In the warm season, the average
chemical composition of the highest days is 82% sulfate, no nitrate, 17%
carbon, and 2% crustal.  In the cool season, the average chemical
composition of the highest days is 50% sulfate, 25% nitrate, 23% carbon,
and 2% crustal.  These data indicate that sources of SO2, NOx, and
direct PM2.5 emissions contribute to violations in the area.

Factor 3: Population density and degree of urbanization (including
commercial development)

Table 4 shows the 2005 population for each county in the area being
evaluated, as well as the population density for each county in that
area.  Population data gives an indication of whether it is likely that
population-based emissions might contribute to violations of the 24-hour
PM2.5 standards. 

Table 4.  Population

County	State Recommended Nonattainment?	2005 Population	2005 Population
Density (pop/mi2)

Hamilton, OH	Yes	   828,487 	2007

Clermont, OH	Yes	190,329 	417

Butler, OH	Yes	   349,966 	745

Dearborn, IN	No	     48,930 	160

Boone, KY	No	   106,278 	414

Warren, OH	Yes	   196,793 	484

Kenton, KY	No	   153,314 	930

Campbell, KY	No	     87,048 	547

All Ohio counties in the Cincinnati area have sizable populations and
population densities.

Factor 4: Traffic and commuting patterns 

This factor considers the number of commuters in each county who drive
to another county within the Cincinnati area, the percent of total
commuters in each county who commute within the area, as well as the
total Vehicle Miles Traveled (VMT) for each county in millions of miles
(see Table 5).  A county with numerous commuters is generally an
integral part of an urban area and is likely contributing to fine
particle concentrations in the area.  

Table 5.  Traffic and Commuting Patterns

County	State Recommended Nonattainment?	2005 VMT

(106 mi)	Number Commuting to any violating counties 	Percent

Commuting to any violating counties 	Number Commuting within statistical
area 	Percent

Commuting within statistical area 

Hamilton, OH	Yes	    8,132 	364,380 	92 	    391,410 	          98 

Butler, OH	Yes	    3,059 	143,800 	90 	    153,070 	          96 

Clermont, OH	Yes	    1,799 	45,070 	51 	      86,620 	          98 

Kenton, KY	No	    1,647 	51,980 	68 	      74,830 	          99 

Warren, OH	Yes	    1,692 	41,510 	54 	      62,590 	          82 

Boone, KY	No	    1,074 	17,300 	39 	      43,420 	          98 

Campbell, KY	No	    1,000 	21,460 	50 	      42,160 	          99 

Dearborn, IN	No	       708 	8,920 	40 	      20,700 	          92 

Montgomery, OH	other	    5,533 	216,610 	84 	      10,610 	            4

The listing of counties on Table 5 reflects a ranking based on the
number of people commuting within the Cincinnati area.  The counties in
bold type are all in the Cincinnati nonattainment area for the 1997
PM2.5 NAAQS.  These data show minimal commuting from Montgomery County
into the Cincinnati area, reflecting the fact that Dayton (the core city
in Montgomery County) is a separate urban area.

The Ohio counties all show high percent of commuting within the
Cincinnati area.  This suggests the counties are linked.

Note:  The 2005 VMT data used for tables 5 and 6 of the technical
analysis have been derived using methodology such as that described in
"Documentation for the 2005 Mobile National Emissions Inventory, Version
2," December 2008, prepared for the Emission Inventory Group, U.S. EPA. 
This document may be found at:   HYPERLINK
"ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/20
05_mobile_nei_version_2_report.pdf" 
ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/200
5_mobile_nei_version_2_report.pdf .

Factor 5:  Growth rates and patterns  

This factor considers population growth for 2000-2005 and growth in
vehicle miles traveled for 1996-2005 for counties in Cincinnati area, as
well as patterns of population and VMT growth.  A county with rapid
population or VMT growth is generally an integral part of an urban area
and likely to be contributing to fine particle concentrations in the
area.

Table 6 below shows population, population growth, VMT, and VMT growth
for counties that are included in the Cincinnati area.  Counties are
listed in descending order based on VMT growth between 1996 and 2005.

Table 6.  Population and VMT Growth and Percent Change

County	Population (2005)	Population % change (2000-05)	2005 VMT

(106 mi)	VMT

% change

(1996-05)

Boone, KY	    106,278 	22 	     1,074 	          48 

Warren, OH	    196,793 	22 	     1,692 	          34 

Dearborn, IN	     48,930 	6 	        708 	          30 

Butler, OH	    349,966 	5 	     3,059 	          28 

Clermont, OH	    190,329 	7 	     1,799 	          16 

Campbell, KY	     87,048 	-2	     1,000 	            4 

Hamilton, OH	    828,487 	-2	     8,132 	            3 

Kenton, KY	    153,314 	1 	     1,647 	            3 

There is robust growth in portions of the Cincinnati area.  In the Ohio
portion of the area, Warren County enjoyed high growth in both
population and VMT.  The other Ohio counties had more modest changes in
population.  Butler and Clermont Counties joined Warren County in having
VMT growth of more that 15%.

Factor 6:  Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service
instruments and other meteorological monitoring sites in the area.  Wind
direction and wind speed data for 2005-2007 were analyzed, with an
emphasis on “high PM2.5 days” for each of two seasons, an
October-April “cold” season and a May-September “warm” season. 
These high days are defined as days where any FRM or FEM air quality
monitors had 24-hour PM2.5 concentrations above 95% on a frequency
distribution curve of PM2.5 24-hour values. 

For each air quality monitoring site, EPA developed a “pollution
rose” to understand the prevailing wind direction and wind speed on
the days with highest fine particle concentrations.  The figure
identifies 24-hour PM2.5 values by color; days exceeding 35 μg/m3 are
denoted with a red or black icon.  A dot indicates the day occurred in
the warm season; a triangle indicates the day occurred in the cool
season.  The center of the figure indicates the location of the air
quality monitoring site, and the location of the icon in relation to the
center indicates the direction from which the wind was blowing on that
day.  An icon that is close to the center indicates a low average wind
speed on that day.  Higher wind speeds are indicated when the icon is
further away from the center.

The pollution rose for the Cincinnati area is provided as Figure 2. 
Winds on high concentration days show a tendency to come from the
Northeast or Southwest.  Overall, the winds come from a variety of
directions.  So, it is appropriate to consider counties in all
directions from the violations.

  Figure 2

Note:  the meteorology factor is also considered in each county’s
Contributing Emissions Score because the method for deriving this metric
included an analysis of trajectories of air masses for high PM2.5 days.

Factor 7:  Geography/topography (mountain ranges or other air basin
boundaries)

The geography/topography analysis evaluates the physical features of the
land that might have an effect on the air shed and, therefore, on the
distribution of PM2.5 over the area.

The Cincinnati 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 the
decision-making process.

Factor 8:  Jurisdictional boundaries

In evaluating the jurisdictional boundary factor, EPA gave special
consideration to areas that were already designated nonattainment in
2005 for violating the 1997 fine particle standards.  Analysis of
chemical composition data in these areas indicates that the same
components that make up most of the PM2.5 mass in the area on an annual
average basis such as sulfate and direct PM2.5 carbon in many eastern
areas also are key contributors to the PM2.5 mass on days exceeding the
24-hour PM2.5 standard.  These data indicate that in many cities, the
same source categories that contribute to violations of the annual
standard also contribute to exceedances of the 24-hour standard.  

EPA has generally concluded that counties that were designated as having
emissions sources contributing to fine particle concentrations which
exceeded the 1997 standards (all areas violated the annual standard, two
also violated the previous 24-hour standard) also contribute to fine
particle concentrations on the highest days.  For this reason, EPA
believes that for most existing nonattainment areas, the nonattainment
area for the 2006 24-hour standard should be the same.  Consideration
also should be given to existing boundaries and organizations as they
may facilitate air quality planning and the implementation of control
measures to attain the standard.  Areas already designated as
nonattainment represent important boundaries for state air quality
planning.

The Ohio-Kentucky-Indiana Regional Council of Governments (OKI) is the
Metropolitan Planning Organization (MPO) for Butler, Warren, Clermont,
and Hamilton Counties in Ohio; Campbell, Kenton, and Boone Counties in
Kentucky; and Dearborn County, Indiana.  OKI webpage:   HYPERLINK
"http://www.oki.org/"  http://www.oki.org/ .  Dayton has a separate MPO,
the Miami Valley Regional Planning Commission which serves Greene,
Miami, Montgomery, and portions of Warren Counties.

The Cincinnati ozone nonattainment area consists of the following
counties: in Ohio- Butler, Clermont, Clinton, Hamilton, and Warren; in
Indiana- Lawrenceburg Township in Dearborn; in Kentucky- Boone, Kenton,
and Campbell.

Factor 9:  Level of control of emission sources 

Under this factor, the existing level of control of emission sources is
taken into consideration.  The emissions data used by EPA in this
technical analysis and provided in Table 1 under Factor 1 represent
emissions levels taking into account any control strategies implemented
in the Cincinnati area before 2005 on stationary, mobile, and area
sources.  Data are presented for PM2.5 components that are directly
emitted, carbonaceous PM2.5 and crustal PM2.5, and for pollutants which
react in the atmosphere to form fine particles such as SO2, NOx, VOC,
and ammonia.  

In considering county-level emissions, EPA used data from the 2005
National Emissions Inventory, the most updated version of the national
inventory available at the beginning of the designations process in late
2007.  However, EPA recognized that for certain counties, emissions may
have changed since 2005.  For example, certain power plants or large
sources of emissions in or near this area may have installed emission
controls or otherwise significantly reduced emissions since 2005.  Some
States provided updated information on emissions and emission controls
in their comments to EPA.  EPA considered such additional information in
making final designation decisions.  

With regard to nearby power plants, EPA considered information about
whether a specific plant installed federally enforceable emission
controls by December 2008 resulting in significant emissions reductions.
 A control requirement is considered to be federally-enforceable if it
is required by a State regulation adopted in a State implementation
plan, if it is included in a federally-enforceable Title V operating
permit, or if it is required by a consent decree which also requires the
controls to be included in federally enforceable permit upon termination
of the consent decree.  In making final decisions, EPA also considered
whether a facility would continue to emit pollutants which contribute to
PM2.5 exceedances even after emission controls are operational. 

Ohio did not provide other information regarding power plants or any
other large sources in the Cincinnati area.

EPA Technical Analysis for Cleveland-Akron-Lorain, Ohio 

In the Cleveland area, Cuyahoga, Lake, Lorain, Medina, Portage, and
Summit Counties along with Ashtabula Township in Ashtabula County are
designated nonattainment for the 1997 PM2.5 standards.  In a December
17, 2007 letter, Ohio recommended the same six full counties as
nonattainment for the 2006 standards.  Ohio recommended the partial
county, Ashtabula County, be designated attainment for the 2006
standards.  Monitoring data shows violations of the 2006 standards in
both Cuyahoga and Summit Counties.

The six counties recommended by Ohio for inclusion in the nonattainment
area all have significant emissions in relatively close proximity to
violating monitors and warrant being judged to contribute to the
violations.  In EPA’s letter to Ohio dated August 18, 2008, EPA
expressed intent to designate Ashtabula Township in Ashtabula County as
nonattainment.  Ohio responded that this township currently has low
emissions and should not be considered to contribute to violations in
the Cleveland area.

On December 9, 2008, Ohio provided supplemental information explaining
the basis for recent drop in emissions in Ashtabula and providing
information that this drop in emissions is permanent and enforceable. 
Until 2002, the Ashtabula Plant, under ownership of Cleveland Electric
Illuminating Company, consisted of a Plant C and a Plant A/B.  The
company then shut down Plant C and sold it to the Ashtabula Port
Authority, which is not using it to burn fuel or generate electricity. 
The Ashtabula Port Authority has acknowledged that it could not restart
this plant without applying for and receiving a new source permit. 
Since the Title V permit for Plant C has expired, and no application for
operation of this plant has been submitted, operation of this plant
would constitute operation without a permit, which would violate
permitting rules.

As a result of this permanent and enforceable shutdown, the emissions
from the Cleveland Electric facility as a whole are substantially lower.
 In particular, the emissions are substantially lower than the levels
that EPA considered for the plant in evaluating designations for the
1997 standards.  Therefore, while EPA judged previous emission levels to
be sufficient to conclude that Ashtabula Township was contributing to
violations in the Cleveland area, current emission levels are
sufficiently low that EPA has concluded that Ashtabula does not now
contribute to violations of the 2006 standards.

The Cleveland area is adjacent to the Canton and Youngstown-Mercer
areas.  These areas have counties with relatively high emissions.  As
discussed elsewhere, EPA intends to designate a Canton nonattainment
area that includes Stark County and a Youngstown nonattainment area that
includes Trumbull and Mahoning Counties.  Based on the technical
analysis below EPA concludes that the metropolitan areas are
sufficiently distinct to warrant treatment as separate areas. 
Therefore, EPA does not intend to include any of these counties in the
Cleveland-Akron nonattainment area.

In summary, EPA is designating the Cleveland nonattainment area under
the 2006 PM2.5 standards that would include Cuyahoga, Lake, Lorain,
Medina, Portage, and Summit Counties, reflecting the same area as was
designated under the 1997 standards except for the exclusion of
Ashtabula Township in Ashtabula County.  These boundaries match the
nonattainment area recommended by the State.  Establishing nonattainment
boundaries similar to the boundaries established for the 1997 standards
has the additional benefit of simplifying planning by assuring that
similar areas are subject to very similar nonattainment planning
requirements.

EPA also considered other nearby counties.  Although Geauga County is
part of the combined statistical area, its emissions are relatively low.
 Aside from Stark, Mahoning, and Trumbull Counties, the counties
adjacent to the Cleveland-Akron area also have relatively low emissions,
and no other factor warranted the inclusion of any of these counties in
the Cleveland-Akron area.

Figure 1 is a map of the counties in the nonattainment area and other
relevant information such as the locations and design values of air
quality monitors, and the metropolitan area boundary. 

 

Figure 1

For this area, EPA previously established PM2.5 nonattainment boundaries
for the 1997 PM2.5 NAAQS that included seven full and partial Ohio
counties.  

In its December 17, 2007 letter, Ohio recommended the above six Ohio
counties be designated as “nonattainment” for the 2006 24-hour PM2.5
standard based on air quality data from 2004-2006.  These data are from
Federal Reference Method (FRM) monitors located in the state.

In August 2008, EPA notified Ohio of its intended designations.  In this
letter, EPA also requested that if the State wished to provide comments
on EPA’s intended designation, it should do so by October 20, 2008. 
EPA stated that it would consider any additional information (e.g., on
power plants or partial county areas) provided by the state in making
final decisions on the designations.  Ohio provided additional
information on the recent emission reductions that occurred in Ashtabula
County.

Based on EPA's technical analysis described below, EPA designated six
Ohio counties as nonattainment for the 24-hour PM2.5 air-quality
standard as part of the Cleveland nonattainment area, based upon
currently available information.  

The following is a review of data for relevant factors for the
Cleveland-Akron-Lorain, Ohio area. 

Factor 1:  Emissions data

For this factor, EPA evaluated county level emission data for the
following PM2.5 components and precursor pollutants:  “PM2.5 emissions
total,” “PM2.5 emissions carbon,” “PM2.5 emissions other,”
“SO2,” “NOx,” “VOCs,” and “NH3.”  “PM2.5 emissions
total” represents direct emissions of PM2.5 and includes: “PM2.5
emissions carbon,” “PM2.5 emissions other”, primary sulfate (SO4),
and primary nitrate.  (Although primary sulfate and primary nitrate,
which are emitted directly from stacks rather than forming in
atmospheric reactions with SO2 and NOx, are part of “PM2.5 emissions
total,” they are not shown in Table 1 as separate items).  “PM2.5
emissions carbon” represents the sum of organic carbon (OC) and
elemental carbon (EC) emissions, and “PM2.5 emissions other”
represents other inorganic particles (crustal).  Emissions of SO2 and
NOx, which are precursors of the secondary PM2.5 components sulfate and
nitrate, are also considered.  VOCs (volatile organic compounds) and NH3
(ammonia) are also potential PM2.5 precursors and are included for
consideration. 

Emissions data were derived from the 2005 National Emissions Inventory
(NEI), version 1.  See
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

EPA also considered the Contributing Emissions Score (CES) for each
county.  The CES is a metric that takes into consideration emissions
data, meteorological data, and air quality monitoring information to
provide a relative ranking of counties in and near an area.  Note that
this metric is not the exclusive manner for considering data for these
factors.  A more detailed description can be found at
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html#C.

Table 1 shows emissions of PM2.5 and precursor pollutants components
(given in tons per year) and the CES for violating and potentially
contributing counties in the Cleveland area.  Counties that are part of
the Cleveland nonattainment area for the 1997 PM2.5 NAAQS are shown in
boldface.  Counties are listed in descending order by CES.

Table 1.  PM2.5 24-hour Component Emissions, and CES

County

	State Recommended Nonattainment?	CES	PM2.5

emissions 

total	PM2.5

emissions 

carbon	PM2.5

emissions 

other	SO2

	NOx

	VOCs

	NH3

Cuyahoga, OH	Yes	100	2,929	1,619	1,310	12,958	48,300	57,105	11,300

Summit, OH	Yes	100	1,031	576	454	12,545	17,359	21,753	923

Lorain, OH	Yes	60	3,691	771	2,920	44,492	23,093	15,939	933

Lake, OH	Yes	43	3,310	463	2,846	80,601	22,288	12,228	350

Stark, OH	Other	18	1,488	574	915	2,334	13,046	19,011	1,902

Medina, OH	Yes	17	1,254	558	696	761	6,853	7,731	669

Portage, OH	Yes	15	1,011	496	514	548	7,269	8,365	564

Wayne, OH	No	15	1,408	468	938	4,812	7,546	6,934	3,702

Trumbull, OH	Other	11	1,730	625	1,105	18,501	13,373	12,098	881

Geauga, OH	No	5	951	461	491	458	3,101	7,162	490

Mahoning, OH	Other	4	722	338	384	1,927	10,086	10,416	1,415

Ashtabula, OH	No	3	1,407	648	758	5,713	14,555	10,988	860

The emissions from several Cleveland area counties are high.  The
emissions from Medina and Portage are slightly lower than Stark County,
which Ohio recommended as nonattainment in the separate Canton area. 
Trumbull and Wayne Counties also have moderate emissions.  The
relatively low CES for Ashtabula County reflects moderate emissions in
the county which were concentrated within Ashtabula Township but a
relatively low frequency of winds blowing from Ashtabula County to
violating monitors on high concentration days and the considerable
distance from the county to the violating monitors.  Ohio has provided
information on unit shut downs that have greatly lowered the emissions
from a power plant in Ashtabula County.  This reduction is not reflected
in the data on Table 1.

Cuyahoga, Lake, Lorain, and Summit Counties are strong candidates for
nonattainment based on this factor.  This factor also suggests Medina,
Portage, and Wayne Counties are potential candidates for inclusion in
the nonattainment area.  Considering the recent emissions reductions,
Ashtabula County is not a candidate for nonattainment based on this
factor.

Table 2 provides the data for CES weighting factors.  The trajectory
factors are used in CES calculations to account for seasonal
meteorology.  For the top 10% of days in both the cold and warm seasons,
wind trajectories were run for a 48 hour period preceding the high
monitor reading.  The amount of time the air mass was over a county
within the mixing height was calculated.  The values were scaled so that
the maximum value is 100.  Thus, the county that is most likely to be
upwind of a monitor on a high concentration day in a season is given a
score of 100.  The scores for the other counties will reflect the
relative likelihood of being upwind.  As the concentration of a
pollutant will decrease as it goes further downwind, a distance
weighting factor is also used in calculating the CES.  The distance
factor listed on Table 2 provides the distance from the center of a
county to the center of the violating county.  If a county is violating,
the distance used is the average distance from the center to the county
line.

  Table 2.  CES Factor Data

County	CES	Trajectory Factor- Cold	Trajectory Factor- Warm	Distance (mi)

Cuyahoga	100	100	85	11.2

Summit	100	72	100	23.6

Lorain	60	73	49	25

Lake	43	56	43	28.9

Stark	18	32	79	47.3

Medina	17	75	83	25.6

Portage	15	50	75	31.9

Wayne	15	44	73	44.5

Trumbull	11	22	39	48.6

Geauga	5	59	54	25.6

Mahoning	4	16	52	56.6

Ashtabula	3	23	22	51.5

Factor 2:  Air quality data 

This factor considers the 24-hour PM2.5 design values (in µg/m3) for
air quality monitors in counties in the Cleveland area based on data for
the 2005-2007 period.  A monitor’s design value indicates whether that
monitor attains a specified air quality standard.  The 24-hour PM2.5
standards are met when the 3-year average of a monitor’s 98th
percentile values are 35 µg/m3 or less.  A design value is only valid
if minimum data completeness criteria are met.

The 24-hour PM2.5 design values for counties in the Cleveland area are
shown in Table 3.  The Cuyahoga and Summit County design values exceed
the 2006 standards and therefore must be included within the
nonattainment area.  Lorain and Portage Counties have air quality that
meets the standards.  There is no monitoring data for Lake and Medina
Counties.  However, the absence of a violating monitor alone is not a
sufficient reason to eliminate counties as candidates for nonattainment
status.  Each county has been evaluated based on the weight of evidence
of the nine factors and other relevant information.  The other counties
showing violations have all been designated nonattainment as part of
separate nonattainment areas based on historical practice, separate
MSAs, and separate economic regions.

	Table 3.  Air Quality Data

County	State 

Recommended

Nonattainment?	Design Values

2004-06

(µg/m3)	Design Values

2005-07

(µg/m3)

Cuyahoga, OH	Yes	43	42

Summit, OH	Yes	38	37

Lorain, OH	Yes	31	32

Lake, OH	Yes

Medina, OH	Yes

Portage, OH	Yes	34	35

Ashtabula, OH	No

Stark, OH	Other	37	36

Wayne, OH	No

Trumbull, OH	Other	36	35

For purposes of its review, EPA used data available from the Chemical
Speciation Network and the Interagency Monitoring of Protected Visual
Environments (IMPROVE) network to estimate the composition of fine
particle mass on days with the highest fine particle concentrations. 
Analysis of these data indicates that the days with the highest fine
particle concentrations in the Cleveland area occur about 63% in the
warm season and 37% in the cool season.  In the warm season, the average
chemical composition of the highest days is 69% sulfate, no nitrate, 23%
carbon, and 8% crustal.  In the cool season, the average chemical
composition of the highest days is 24% sulfate, 36% nitrate, 34% carbon,
and 6% crustal.  These data indicate that sources of SO2, NOx, and
direct PM2.5 emissions contribute to violations in the area.

Factor 3: Population density and degree of urbanization (including
commercial development)

Table 4 shows the 2005 population for each county in the area being
evaluated, as well as the population density for each county in that
area.  Population data gives an indication of whether it is likely that
population-based emissions might contribute to violations of the 24-hour
PM2.5 standards. 

Table 4.  Population

County	State Recommended Nonattainment?	2005 Population	2005 Population
Density (pop/sq mi)

Cuyahoga, OH	Yes	 1,330,428 	2900

Summit, OH	Yes	    546,285 	1302

Lorain, OH	Yes	    300,266 	608

Lake, OH	Yes	    232,416 	1004

Medina, OH	Yes	    166,968 	395

Portage, OH	Yes	    155,150 	307

Ashtabula, OH	No	    103,044 	145

Wayne, OH	No	    113,496 	204

Geauga, OH	No	     95,060 	233

Cuyahoga County with the city of Cleveland has the highest population. 
Summit County follows with about half the population.  The other
counties are lower with Ashtabula, Wayne, and Geauga having the smallest
population in the Cleveland area.  Based on this table, the six counties
recommended for nonattainment by Ohio can be expected to have the great
majority of the population-oriented emissions of the area, and EPA
concludes that they all qualify for designation based on contribution
under this factor.

Factor 4: Traffic and commuting patterns 

This factor considers the number of commuters in each county who drive
to another county within the Cleveland area, the percent of total
commuters in each county who commute within the area, as well as the
total Vehicle Miles Traveled (VMT) for each county in millions of miles
(see Table 5).  A county with numerous commuters is generally an
integral part of an urban area and is likely contributing to fine
particle concentrations in the area.  

Table 5.  Traffic and Commuting Patterns

County	State Recommended Nonattainment?	2005 VMT

(106 mi)	Number Commuting to any violating counties 	Percent

Commuting to any violating counties 	Number Commuting into statistical
area 	Percent

Commuting into statistical area 

Cuyahoga, OH	Yes	 11,017 	596,930 	96 	    615,890 	          99 

Summit, OH	Yes	   4,929 	237,910 	92 	    245,630 	          95 

Lorain, OH	Yes	   3,044 	38,300 	29 	    129,280 	          98 

Lake, OH	Yes	   1,881 	111,000 	95 	    115,760 	          99 

Medina, OH	Yes	   1,721 	36,030 	47 	      73,030 	          96 

Portage, OH	Yes	   1,788 	35,070 	45 	      73,350 	          94 

Ashtabula, OH	No	   1,182 	9,280 	20 	      44,070 	          97 

Wayne, OH	No	   1,044 	6,920 	13 	      10,100 	          19 

Geauga, OH	No	      834 	23,600 	53 	      43,490 	          98 

Stark, OH	Other	   3,049 	165,560 	94 	      26,820 	          15

Trumbull, OH	Other	   2,153 	88,870 	91 	        9,890 	          10

Mahoning, OH	Other	   2,666 	101,330 	93 	        3,710 	            3

The listing of counties on Table 5 reflects a ranking based on the
number of people commuting within the Cleveland area.  The counties in
bold type are all in the Cleveland nonattainment area for the 1997 PM2.5
NAAQS.  Cuyahoga, Lake, and Summit Counties all have a high percent of
commuting into violating counties.  Geauga, Medina, and Portage Counties
have a fair amount of commuting into violating counties, though Geauga
County has the lowest VMT in the area suggesting little contribution
based on this factor.  The low percent of commuting into the Cleveland
statistical area from Wayne and into the violating counties from both
Wayne and Ashtabula Counties suggests that they are separate from the
Cleveland area and therefore not contributing based on this factor. 
Thus, the six counties recommended for nonattainment by Ohio represent
an integrated area that warrants being treated together as a single
nonattainment area.  These data show minimal commuting from Mahoning,
Stark, and Trumbull Counties into the adjacent to the Cleveland area. 
Thus, these data support treating Canton and Youngstown as separate
urban areas.

Note:  The 2005 VMT data used for tables 5 and 6 of the technical
analysis have been derived using methodology such as that described in
"Documentation for the 2005 Mobile National Emissions Inventory, Version
2," December 2008, prepared for the Emission Inventory Group, U.S. EPA. 
This document may be found at:   HYPERLINK
"ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/20
05_mobile_nei_version_2_report.pdf" 
ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/200
5_mobile_nei_version_2_report.pdf .

Factor 5:  Growth rates and patterns  

This factor considers population growth for 2000-2005 and growth in
vehicle miles traveled for 1996-2005 for counties in the Cleveland area,
as well as patterns of population and VMT growth.  A county with rapid
population or VMT growth is generally an integral part of an urban area
and likely to be contributing to fine particle concentrations in the
area.

Table 6 below shows population, population growth, VMT, and VMT growth
for counties that are included in the Cleveland area.  Counties are
listed in descending order based on VMT growth between 1996 and 2005.

Table 6.  Population and VMT Growth and Percent Change.

County	Population (2005)	Population % change (2000-2005)	2005 VMT

(106 mi)	VMT

% change

(1996-2005)

Lorain, OH	    300,266 	5 	     3,044 	          26 

Ashtabula, OH	    103,044 	0 	     1,182 	          13 

Medina, OH	    166,968 	10 	     1,721 	          12 

Portage, OH	    155,150 	2 	     1,788 	            6 

Wayne, OH	    113,496 	2 	     1,044	            6 

Summit, OH	    546,285 	0 	     4,929 	            1 

Lake, OH	    232,416 	2 	     1,881 	            1 

Geauga, OH	     95,060 	4 	        921 	           -2  

Cuyahoga, OH	 1,330,428 	-4	    10,482 	           -7

The population of Medina County grew by 10% during the 2000 to 2005
period.  The population change for the other counties in the area was 5%
or less.  Lorain County had the largest VMT percent growth.  Ashtabula
and Medina Counties also experienced strong VMT growth.  Cuyahoga and
Geauga Counties had a decrease in VMT during the 1996 to 2005 period. 
The growth rates suggest that the distribution of population and VMT
will not change significantly during the SIP planning time horizon, thus
this factor was less significant in determining the boundary of the
nonattainment area.

Factor 6:  Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service
instruments and other meteorological monitoring sites in the area.  Wind
direction and wind speed data for 2005-2007 were analyzed, with an
emphasis on “high PM2.5 days” for each of two seasons, an
October-April “cold” season and a May-September “warm” season. 
These high days are defined as days where any FRM or FEM air quality
monitors had 24-hour PM2.5 concentrations above 95% on a frequency
distribution curve of PM2.5 24-hour values. 

g 35 μg/m3 are denoted with a red or black icon.  A dot indicates the
day occurred in the warm season; a triangle indicates the day occurred
in the cool season.  The center of the figure indicates the location of
the air quality monitoring site, and the location of the icon in
relation to the center indicates the direction from which the wind was
blowing on that day.  An icon that is close to the center indicates a
low average wind speed on that day.  Higher wind speeds are indicated
when the icon is further away from the center.

The pollution rose for the Cleveland area is provided as Figure 2. 
Winds on high concentration days show a tendency to come from the South.
 Overall, the winds come from a variety of directions.  So, it is
appropriate to consider counties in all directions from the violations. 
This factor indicates contribution from all surrounding counties that
have sufficient emissions levels.

 

Figure 2

Note:  the meteorology factor is also considered in each county’s
Contributing Emissions Score because the method for deriving this metric
included an analysis of trajectories of air masses for high PM2.5 days.

Factor 7:  Geography/topography (mountain ranges or other air basin
boundaries)

The geography/topography analysis evaluates the physical features of the
land that might have an effect on the air shed and, therefore, on the
distribution of PM2.5 over the area.

The Cleveland 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 the
decision-making process.

Factor 8:  Jurisdictional boundaries

In evaluating the jurisdictional boundary factor, EPA gave special
consideration to areas that were already designated nonattainment in
2005 for violating the 1997 fine particle standards.  Analysis of
chemical composition data in these areas indicates that the same
components that make up most of the PM2.5 mass in the area on an annual
average basis such as sulfate and direct PM2.5 carbon in many eastern
areas also are key contributors to the PM2.5 mass on days exceeding the
24-hour PM2.5 standard.  These data indicate that in many cities, the
same source categories that contribute to violations of the annual
standard also contribute to exceedances of the 24-hour standard.  

EPA has generally concluded that counties that were designated as having
emissions sources contributing to fine particle concentrations which
exceeded the 1997 standards (all areas violated the annual standard, two
also violated the previous 24-hour standard) also contribute to fine
particle concentrations on the highest days.  For this reason, EPA
believes that for most existing nonattainment areas, the nonattainment
area for the 2006 24-hour standard should be the same.  Consideration
also should be given to existing boundaries and organizations as they
may facilitate air quality planning and the implementation of control
measures to attain the standard.  Areas already designated as
nonattainment represent important boundaries for state air quality
planning.

The Northeast Ohio Area wide Coordinating Agency (NOACA) is the
Metropolitan Planning Organization (MPO) for Cuyahoga, Geauga, Lake
(OH), Lorain, and Medina Counties.  NOACA webpage,   HYPERLINK
"http://www.noaca.org/"  http://www.noaca.org/ .  Youngstown has a
separate MPO, the Eastgate Regional Council of Governments which serves
Mahoning and Trumbull Counties in Ohio. 

The Cleveland ozone nonattainment area consists of the following
counties:  Ashtabula, Cuyahoga, Geauga, Lake, Lorain, Medina, Portage,
and Summit.

The Cleveland nonattainment area is nearly identical to the
nonattainment area designated under the 1997 PM2.5 standard, which would
facilitate planning.  The partial county portion in Ashtabula County was
previously designated nonattainment, but now is considered as attainment
based on significantly lower emissions levels.  The rest of the
Cleveland area is the same.

Factor 9:  Level of control of emission sources 

Under this factor, the existing level of control of emission sources is
taken into consideration.  The emissions data used by EPA in this
technical analysis and provided in Table 1 under Factor 1 represent
emissions levels taking into account any control strategies implemented
in the Cleveland area before 2005 on stationary, mobile, and area
sources.  Data are presented for PM2.5 components that are directly
emitted, carbonaceous PM2.5 and crustal PM2.5, and for pollutants which
react in the atmosphere to form fine particles such as SO2, NOx, VOC,
and ammonia.  

In considering county-level emissions, EPA used data from the 2005
National Emissions Inventory, the most updated version of the national
inventory available at the beginning of the designations process in late
2007.  However, EPA recognized that for certain counties, emissions may
have changed since 2005.  For example, certain power plants or large
sources of emissions in or near this area may have installed emission
controls or otherwise significantly reduced emissions since 2005.  Some
States provided updated information on emissions and emission controls
in their comments to EPA.  EPA considered such additional information in
making final designation decisions.  

With regard to nearby power plants, EPA considered information about
whether a specific plant installed federally enforceable emission
controls by December 2008 resulting in significant emissions reductions.
 A control requirement is considered to be federally-enforceable if it
is required by a State regulation adopted in a State implementation
plan, if it is included in a federally-enforceable Title V operating
permit, or if it is required by a consent decree which also requires the
controls to be included in federally enforceable permit upon termination
of the consent decree.  In making final decisions, EPA also considered
whether a facility would continue to emit pollutants which contribute to
PM2.5 exceedances even after emission controls are operational. 

Ohio provided information regarding the large reductions at the
Ashtabula power plant.  Large emission reductions have resulted from
unit shutdowns at the Ashtabula County facility.  The units of Plant C
at this facility have been sold to another company that does not intend
to restart the units and acknowledges that restarting the units would
require a new source permit authorizing their operation due to the
current shutdown.  Ohio also noted that the Title V permit covering
Plant C has expired, no application for a Title V permit for Plant C has
been received, and so operation of Plant C without a permit would be a
violation of permitting rules.  EPA concludes that the reduction of
emissions from the shutdown of Plant C is permanent and enforceable.  As
a result of the shutdown of this facility, EPA concludes that the
significantly lower emissions form Ashtabula County, which is not
significant for any other factor, indicate that Ashtabula County is not
contributing to the violating monitors at this time.

EPA Technical Analysis for Columbus, Ohio 

The Columbus, Ohio nonattainment area under the 1997 standards is
comprised of Delaware, Fairfield, Franklin, and Licking Counties along
with Franklin Township in Coshocton County.  For the 2006 standards,
Ohio recommended Delaware, Fairfield, Franklin, and Licking Counties be
designated nonattainment in its December 17, 2007 letter.  The partial
county area, Franklin Township in Coshocton County, was not included in
Ohio’s recommended nonattainment area.  Monitored air quality values
show that Franklin County has exceeded the 2006 standards.  No other
county in the combined statistical area has monitoring data.

EPA agrees that the four counties recommended by Ohio to be
nonattainment warrant inclusion in the nonattainment area.  Franklin
County likely makes the greatest contribution to violations within the
area, however Delaware, Fairfield, and Licking Counties all have
substantial emissions, populations, traffic, and growth rates that
indicate contribution to the violations in Franklin County.  

Coshocton County emissions are also substantial.  Direct fine
particulate and nitrogen oxides emissions are among the highest of the
candidate nonattainment counties in the Columbus area, and winds
sometimes carry those emissions to the violating monitor on high
concentration days.  Current sulfur dioxide emissions from Coshocton
County far exceed the emissions from any other Columbus area county. 
These emissions arise predominantly from the Conesville power plant in
Franklin Township.  EPA understands that two units of this plant are
well controlled.  According to Ohio’s comments, the owner of this
plant is installing controls that will commence operation in mid-2009. 
However, current emissions are relatively high.  Therefore, EPA believes
at the present time that emissions in Franklin Township of Coshocton
County are substantial and continue to contribute to nonattainment in
the Columbus area.  This reflects EPA’s approach of designating
according to current air quality and current contributions to violations
as required by the Act, irrespective of whether emissions may be reduced
in the future.  However, as Coshocton County ranks low for all other
factors EPA concludes that it is appropriate to designate only Franklin
County as nonattainment for the 2006 standards.

EPA is designating a Columbus nonattainment area that includes Delaware,
Fairfield, Franklin, and Licking Counties and Franklin Township in
Coshocton County.  Establishing nonattainment boundaries that match the
boundaries established for the 1997 standards has the additional benefit
of simplifying planning by assuring that the same areas are subject to
very similar nonattainment planning requirements.  EPA examined relevant
information for other counties in and around the Columbus area and
concluded that other counties have relatively low emissions, and no
other factor warrants inclusion of these counties in the nonattainment
area.

Figure 1 is a map of the counties in the nonattainment area and other
relevant information such as the locations and design values of air
quality monitors, and the metropolitan area boundary. 

 

Figure 1

For this area, EPA previously established PM2.5 nonattainment boundaries
for the 1997 PM2.5 NAAQS that included five full and partial counties in
Ohio.  

In its December 17, 2007 letter, Ohio recommended the four of the same
Ohio counties be designated as “nonattainment” for the 2006 24-hour
PM2.5 standard based on air quality data from 2004-2006.  Ohio
recommended all of Coshocton County be designated as “attainment”. 
One township of Coshocton County is included in the Columbus
nonattainment area for the 2006 24-hour PM2.5 standard.  These data are
from Federal Reference Method (FRM) monitors located in the state.

In August 2008, EPA notified Ohio of its intended designations.  In this
letter, EPA also requested that if the State wished to provide comments
on EPA’s intended designation, it should do so by October 20, 2008. 
EPA stated that it would consider any additional information (e.g., on
power plants or partial county areas) provided by the state in making
final decisions on the designations.  

Based on EPA's technical analysis described below, EPA designated five
full and partial counties in Ohio as nonattainment for the 24-hour PM2.5
air-quality standard as part of the Columbus nonattainment area, based
upon currently available information.  

The following is a review of data for relevant factors for the Columbus,
Ohio area. 

Factor 1:  Emissions data

For this factor, EPA evaluated county level emission data for the
following PM2.5 components and precursor pollutants:  “PM2.5 emissions
total,” “PM2.5 emissions carbon,” “PM2.5 emissions other,”
“SO2,” “NOx,” “VOCs,” and “NH3.”  “PM2.5 emissions
total” represents direct emissions of PM2.5 and includes: “PM2.5
emissions carbon,” “PM2.5 emissions other”, primary sulfate (SO4),
and primary nitrate.  (Although primary sulfate and primary nitrate,
which are emitted directly from stacks rather than forming in
atmospheric reactions with SO2 and NOx, are part of “PM2.5 emissions
total,” they are not shown in Table 1 as separate items).  “PM2.5
emissions carbon” represents the sum of organic carbon (OC) and
elemental carbon (EC) emissions, and “PM2.5 emissions other”
represents other inorganic particles (crustal).  Emissions of SO2 and
NOx, which are precursors of the secondary PM2.5 components sulfate and
nitrate, are also considered.  VOCs (volatile organic compounds) and NH3
(ammonia) are also potential PM2.5 precursors and are included for
consideration. 

Emissions data were derived from the 2005 National Emissions Inventory
(NEI), version 1.  See
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

EPA also considered the Contributing Emissions Score (CES) for each
county.  The CES is a metric that takes into consideration emissions
data, meteorological data, and air quality monitoring information to
provide a relative ranking of counties in and near an area.  Note that
this metric is not the exclusive manner for considering data for these
factors.  A more detailed description can be found at
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html#C.

Table 1 shows emissions of PM2.5 and precursor pollutants components
(given in tons per year) and the CES for violating and potentially
contributing counties in the Columbus area.  Counties that are part of
the Columbus nonattainment area for the 1997 PM2.5 NAAQS are shown in
boldface.  Counties are listed in descending order by CES.

Table 1.  PM2.5 24-hour Component Emissions, and CESs. 

County	State Recommended Nonattainment?	CES	PM2.5

emissions 

total	PM2.5

emissions 

carbon	PM2.5

emissions 

other	SO2

	NOx

	VOCs

	NH3

Franklin, OH	Yes	100	2,366	1,327	1,039	4,094	37,707	42,607	2,002

Pickaway, OH	No	19	1,214	233	981	6,797	5,022	3,027	1,308

Adams, OH	No	18	5,970	494	5,476	126,316	33,822	1,918	837

Ross, OH	No	18	920	339	581	24,424	6,725	3,947	1,037

Coshocton, OH	No	16	6,842	483	6,358	106,802	23,057	2,349	1,108

Delaware, OH	Yes	11	1,382	515	868	581	6,803	6,751	695

Licking, OH	Yes	10	1,949	759	1,192	766	7,437	7,326	2,626

Fairfield, OH	Yes	9	1,108	389	719	450	5,942	4,929	1,377

The CES for Franklin County is distinctly higher than the scores for the
other counties.  None of the scores for the other counties stand out. 
Adams and Coshocton Counties are notable for the high sulfur dioxide
emissions from both counties.  However, Adams County is in the
Huntington-Ashland nonattainment area under the 1997 standards and does
not rank highly for any other factors.  The other counties have moderate
emissions.

Table 2 provides the data for CES weighting factors.  The trajectory
factors are used in CES calculations to account for seasonal
meteorology.  For the top 10% of days in both the cold and warm seasons,
wind trajectories were run for a 48 hour period preceding the high
monitor reading.  The amount of time the air mass was over a county
within the mixing height was calculated.  The values were scaled so that
the maximum value is 100.  Thus, the county that is most likely to be
upwind of a monitor on a high concentration day in a season is given a
score of 100.  The scores for the other counties will reflect the
relative likelihood of being upwind.  As the concentration of a
pollutant will decrease as it goes further downwind, a distance
weighting factor is also used in calculating the CES.  The distance
factor listed on Table 2 provides the distance from the center of a
county to the center of the violating county.  If a county is violating,
the distance used is the average distance from the center to the county
line.

  Table 2.  CES Factor Data.

County	CES	Trajectory Factor- Cold	Trajectory Factor- Warm	Distance (mi)

Franklin	100	100	100	13.1

Pickaway	19	85	97	22.8

Adams	18	21	24	82.9

Ross	18	52	60	43.5

Coshocton	16	27	15	62.9

Delaware	11	74	57	21.9

Licking	10	69	55	29.6

Fairfield	9	87	84	26.1

Factor 2:  Air quality data 

This factor considers the 24-hour PM2.5 design values (in µg/m3) for
air quality monitors in counties in the Columbus area based on data for
the 2005-2007 period.  A monitor’s design value indicates whether that
monitor attains a specified air quality standard.  The 24-hour PM2.5
standards are met when the 3-year average of a monitor’s 98th
percentile values are 35 µg/m3 or less.  A design value is only valid
if minimum data completeness criteria are met.

The 24-hour PM2.5 design values for counties in the Columbus area are
shown in Table 3.  Franklin County is the only area with monitoring
data.  Its design value exceeds the air quality standards.

	Table 3.  Air Quality Data

County	State 

Recommended

Nonattainment?	Design Values

2004-2006	Design Values

2005-2007

Franklin, OH	Yes	38	38

Coshocton, OH	No	0	0

Delaware, OH	Yes	0	0

Licking, OH	Yes	0	0

Fairfield, OH	Yes	0	0

For purposes of its review, EPA used data available from the Chemical
Speciation Network and the Interagency Monitoring of Protected Visual
Environments (IMPROVE) network to estimate the composition of fine
particle mass on days with the highest fine particle concentrations. 
Analysis of these data indicates that the days with the highest fine
particle concentrations in the Columbus area occur about 74% in the warm
season and 26% in the cool season.  In the warm season, the average
chemical composition of the highest days is 81% sulfate, no nitrate, 17%
carbon, and 2% crustal.  In the cool season, the average chemical
composition of the highest days is 33% sulfate, 32% nitrate, 33% carbon,
and 2% crustal.  These data indicate that sources of SO2, NOx, and
direct PM2.5 emissions contribute to violations in the area.

Factor 3: Population density and degree of urbanization (including
commercial development)

Table 4 shows the 2005 population for each county in the area being
evaluated, as well as the population density for each county in that
area.  Population data gives an indication of whether it is likely that
population-based emissions might contribute to violations of the 24-hour
PM2.5 standards. 

Table 4.  Population

County	State Recommended Nonattainment?	2005 Population	2005 Population
Density (pop/sq mi)

Franklin, OH	Yes	 1,089,365 	2007

Licking, OH	Yes	    154,683 	225

Delaware, OH	Yes	    150,496 	330

Fairfield, OH	Yes	    138,403 	272

Ross, OH	No	      75,135 	109

Pickaway, OH	No	      52,837 	104

Coshocton, OH	No	      36,969 	65

Adams, OH	No	      28,454 	49

Franklin County has the largest population.  Delaware, Fairfield, and
Licking Counties have moderate populations.  Thus, these four counties
would be included in the nonattainment area based on this factor.  The
other counties all have modest populations and would not be recommended
for inclusion based on this factor.

Factor 4: Traffic and commuting patterns 

This factor considers the number of commuters in each county who drive
to another county within the Columbus area, the percent of total
commuters in each county who commute within the area, as well as the
total Vehicle Miles Traveled (VMT) for each county in millions of miles
(see Table 5).  A county with numerous commuters is generally an
integral part of an urban area and is likely contributing to fine
particle concentrations in the area.  

Table 5.  Traffic and Commuting Patterns

County	State Recommended Nonattainment?	2005 VMT

(106 mi)	Number Commuting to any violating counties 	Percent

Commuting to any violating counties 	Number Commuting into statistical
area 	Percent

Commuting into statistical area 

Franklin, OH	Yes	   10,724 	508,840 	93 	    539,670 	          99 

Licking, OH	Yes	     1,669 	23,780 	34 	      68,970 	          97 

Fairfield, OH	Yes	     1,232 	28,280 	47 	      58,710 	          98 

Delaware, OH	Yes	     1,417 	31,720 	55 	      56,510 	          98 

Ross, OH	No	        654 	2,360 	8 	      27,510 	          91 

Pickaway, OH	No	        464 	9,640 	44 	      21,440 	          99 

Coshocton, OH	No	        307 	270 	2 	           970 	            6 

Adams, OH	No	        283 	20 	0 	           110 	            1 

The listing of counties on Table 5 reflects a ranking based on the
number of people commuting within the Columbus area.  Adams and
Coshocton Counties show little commuting into the Columbus area.  The
other counties all show high percent of commuting within the Columbus
area.  This suggests these counties are linked economically and likely
contribute emissions to the violating monitors based on this factor.

Note:  The 2005 VMT data used for table 5 and 6 of the 9-factor analysis
has been derived using methodology similar to that described in
“Documentation for the final 2002 Mobile National Emissions Inventory,
Version 3, September 2007, prepared for the Emission Inventory Group,
U.S. EPA.  This document may be found at:
ftp://ftp.epa.gov/EmisInventory/2002finalnei/documentation/mobile/2002_m
obile_nei_version_3_report_092807.pdf.  The 2005 VMT data were taken
from documentation which is still draft, but which should be released in
2008.

Factor 5:  Growth rates and patterns  

This factor considers population growth for 2000-2005 and growth in
vehicle miles traveled for 1996-2005 for counties in Columbus area, as
well as patterns of population and VMT growth.  A county with rapid
population or VMT growth is generally an integral part of an urban area
and likely to be contributing to fine particle concentrations in the
area.

Table 6 below shows population, population growth, VMT, and VMT growth
for counties that are included in the Columbus area.  Counties are
listed in descending order based on VMT growth between 1996 and 2005.

Table 6.  Population and VMT Growth and Percent Change.

Location	Population (2005)	Population % change (2000-2005)	2005 VMT

(106 mi)	VMT

% change

(1996-2005)

Delaware, OH	    150,496 	35 	     1,417 	          38 

Licking, OH	    154,683 	6 	     1,669 	          22 

Fairfield, OH	    138,403 	12 	     1,232 	          21 

Franklin, OH	 1,089,365 	2 	    10,724	          19 

Coshocton, OH	     36,969 	1 	        307 	            4 

Delaware County grew rapidly during the 2000 to 2005 period.  Fairfield
County had substantial growth while the other area counties experienced
limited population expansion during that time.  Delaware County also had
the most VMT growth.  The other counties had significant VMT growth as
well with one exception.  Coshocton County had just a 4% increase to its
small VMT.  These data support continuing to include the three “collar
counties” in the nonattainment area.  However, Coshocton County as a
whole would not be recommended for inclusion under this factor.

Factor 6:  Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service
instruments and other meteorological monitoring sites in the area.  Wind
direction and wind speed data for 2005-2007 were analyzed, with an
emphasis on “high PM2.5 days” for each of two seasons, an
October-April “cold” season and a May-September “warm” season. 
These high days are defined as days where any FRM or FEM air quality
monitors had 24-hour PM2.5 concentrations above 95% on a frequency
distribution curve of PM2.5 24-hour values. 

by color; days exceeding 35 μg/m3 are denoted with a red or black icon.
 A dot indicates the day occurred in the warm season; a triangle
indicates the day occurred in the cool season.  The center of the figure
indicates the location of the air quality monitoring site, and the
location of the icon in relation to the center indicates the direction
from which the wind was blowing on that day.  An icon that is close to
the center indicates a low average wind speed on that day.  Higher wind
speeds are indicated when the icon is further away from the center.

The pollution rose for the Columbus area is provided as Figure 2.  Winds
on high concentration days come from a variety of directions.  So, it is
appropriate to consider counties in all directions from the violation. 
The wind rose indicates that any nearby surrounding counties with high
emissions could contribute to the violating monitors.

 

Figure 2

Note:  the meteorology factor is also considered in each county’s
Contributing Emissions Score because the method for deriving this metric
included an analysis of trajectories of air masses for high PM2.5 days.

Factor 7:  Geography/topography (mountain ranges or other air basin
boundaries)

The geography/topography analysis evaluates the physical features of the
land that might have an effect on the air shed and, therefore, on the
distribution of PM2.5 over the area.

The Columbus 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 the
decision-making process.

Factor 8:  Jurisdictional boundaries

In evaluating the jurisdictional boundary factor, EPA gave special
consideration to areas that were already designated nonattainment in
2005 for violating the 1997 fine particle standards.  Analysis of
chemical composition data in these areas indicates that the same
components that make up most of the PM2.5 mass in the area on an annual
average basis such as sulfate and direct PM2.5 carbon in many eastern
areas also are key contributors to the PM2.5 mass on days exceeding the
24-hour PM2.5 standard.  These data indicate that in many cities, the
same source categories that contribute to violations of the annual
standard also contribute to exceedances of the 24-hour standard.  

EPA has generally concluded that counties that were designated as having
emissions sources contributing to fine particle concentrations which
exceeded the 1997 standards (all areas violated the annual standard, two
also violated the previous 24-hour standard) also contribute to fine
particle concentrations on the highest days.  For this reason, EPA
believes that for most existing nonattainment areas, the nonattainment
area for the 2006 24-hour standard should be the same.  Consideration
also should be given to existing boundaries and organizations as they
may facilitate air quality planning and the implementation of control
measures to attain the standard.  Areas already designated as
nonattainment represent important boundaries for state air quality
planning.

The Mid-Ohio Regional Planning Commission (MORPC) is the Metropolitan
Planning Organization (MPO) for the Columbus, Ohio area.  MORPC webpage,
http://www.morpc.org/MORPC.htm. 

The area's ozone nonattainment area consists of the following counties: 
Delaware, Franklin, Licking, Fairfield, Madison, and Knox.

The designated Columbus, Ohio nonattainment area is identical to the
nonattainment area designated under the 1997 PM2.5 standard, which will
facilitate air quality planning.

Factor 9:  Level of control of emission sources 

Under this factor, the existing level of control of emission sources is
taken into consideration.  The emissions data used by EPA in this
technical analysis and provided in Table 1 under Factor 1 represent
emissions levels taking into account any control strategies implemented
in the Columbus area before 2005 on stationary, mobile, and area
sources.  Data are presented for PM2.5 components that are directly
emitted, carbonaceous PM2.5 and crustal PM2.5, and for pollutants which
react in the atmosphere to form fine particles such as SO2, NOx, VOC,
and ammonia.  

In considering county-level emissions, EPA used data from the 2005
National Emissions Inventory, the most updated version of the national
inventory available at the beginning of the designations process in late
2007.  However, EPA recognized that for certain counties, emissions may
have changed since 2005.  For example, certain power plants or large
sources of emissions in or near this area may have installed emission
controls or otherwise significantly reduced emissions since 2005.  Some
States provided updated information on emissions and emission controls
in their comments to EPA.  EPA considered such additional information in
making final designation decisions.  

With regard to nearby power plants, EPA considered information about
whether a specific plant installed federally enforceable emission
controls by December 2008 resulting in significant emissions reductions.
 A control requirement is considered to be federally-enforceable if it
is required by a State regulation adopted in a State implementation
plan, if it is included in a federally-enforceable Title V operating
permit, or if it is required by a consent decree which also requires the
controls to be included in federally enforceable permit upon termination
of the consent decree.  In making final decisions, EPA also considered
whether a facility would continue to emit pollutants which contribute to
PM2.5 exceedances even after emission controls are operational. 

Ohio provided information regarding emission controls planned for the
Conesville power plant in Coshocton County.  This information indicates
that sulfur dioxide emission controls are in place for two medium sized
units, planned for June 2009 for one large unit, and are not planned for
one small unit.  Nitrogen oxide emissions are reduced with a staged
combustion process and not with supplemental control systems except that
the company is installing selective catalytic control equipment on the
large unit by June 2009.  EPA concludes that the 2005 emission estimates
accurately represent current emissions, until further controls are
completed.  Ohio did not address the enforceability of the planned
controls.

EPA Technical Analysis for Dayton-Springfield, Ohio 

The Dayton-Springfield nonattainment area as designated under the 1997
standards included Clark, Greene, and Montgomery Counties.  On December
17, 2007, Ohio recommended including only Greene and Montgomery Counties
in the nonattainment area under the 2006 standards.  Violations are
being observed in Montgomery and Clark Counties.   

EPA agrees with Ohio that Montgomery and Greene Counties should be
included in the nonattainment area, because emissions in these counties
are relatively high and wind patterns and commuting patterns support the
conclusion that these counties contribute to the observed violations. 
EPA believes that Clark County must also be included in the
nonattainment area, because Clark County has monitored violations of the
standard.  Clark County also has sufficient emissions to be judged to be
contributing to violations in both Clark and Montgomery Counties. 
Establishing nonattainment boundaries that match the boundaries
established for the 1997 standards would have the additional benefit of
simplifying planning by assuring that the same areas are subject to very
similar nonattainment planning requirements.  

Despite the proximity of the Dayton area to the Cincinnati area, EPA
views these two nonattainment areas as sufficiently distinct to be
treated as separate areas.  Other counties in and around the Dayton area
have relatively low emissions, and no other factor warrants inclusion of
the counties in the nonattainment area.

Figure 1 is a map of the counties in the nonattainment area and other
relevant information such as the locations and design values of air
quality monitors, and the metropolitan area boundary. 

 Figure 1

For this area, EPA previously established PM2.5 nonattainment boundaries
for the 1997 PM2.5 NAAQS that included three Ohio counties.  

In its December 17, 2007 letter, Ohio recommended two counties be
designated as “nonattainment” for the 2006 24-hour PM2.5 standard
based on air quality data from 2004-2006.  These data are from Federal
Reference Method (FRM) monitors located in the state.

In August 2008, EPA notified Ohio of its intended designations.  In this
letter, EPA also requested that if the State wished to provide comments
on EPA’s intended designation, it should do so by October 20, 2008. 
EPA stated that it would consider any additional information (e.g., on
power plants or partial county areas) provided by the state in making
final decisions on the designations.  

Based on EPA's technical analysis described below, EPA designated three
Ohio counties as nonattainment for the 24-hour PM2.5 air-quality
standard as part of the Dayton nonattainment area, based upon currently
available information.

The following is a review of data for relevant factors for the
Dayton-Springfield, Ohio area. 

Factor 1:  Emissions data

For this factor, EPA evaluated county level emission data for the
following PM2.5 components and precursor pollutants:  “PM2.5 emissions
total,” “PM2.5 emissions carbon,” “PM2.5 emissions other,”
“SO2,” “NOx,” “VOCs,” and “NH3.”  “PM2.5 emissions
total” represents direct emissions of PM2.5 and includes: “PM2.5
emissions carbon,” “PM2.5 emissions other”, primary sulfate (SO4),
and primary nitrate.  (Although primary sulfate and primary nitrate,
which are emitted directly from stacks rather than forming in
atmospheric reactions with SO2 and NOx, are part of “PM2.5 emissions
total,” they are not shown in Table 1 as separate items).  “PM2.5
emissions carbon” represents the sum of organic carbon (OC) and
elemental carbon (EC) emissions, and “PM2.5 emissions other”
represents other inorganic particles (crustal).  Emissions of SO2 and
NOx, which are precursors of the secondary PM2.5 components sulfate and
nitrate, are also considered.  VOCs (volatile organic compounds) and NH3
(ammonia) are also potential PM2.5 precursors and are included for
consideration. 

Emissions data were derived from the 2005 National Emissions Inventory
(NEI), version 1.  See
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

EPA also considered the Contributing Emissions Score (CES) for each
county.  The CES is a metric that takes into consideration emissions
data, meteorological data, and air quality monitoring information to
provide a relative ranking of counties in and near an area.  Note that
this metric is not the exclusive manner for considering data for these
factors.  A more detailed description can be found at
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html#C.

Table 1 shows emissions of PM2.5 and precursor pollutants components
(given in tons per year) and the CES for violating and potentially
contributing counties in the Dayton area.  Counties that are part of the
Dayton nonattainment area for the 1997 PM2.5 NAAQS are shown in
boldface.  Counties are listed in descending order by CES.

Table 1.  PM2.5 24-hour Component Emissions, and CESs

County	State Recommended Nonattainment?	CES	PM2.5

emissions 

total	PM2.5

emissions 

carbon	PM2.5

emissions 

other	SO2

	NOx

	VOCs

	NH3

Montgomery, OH	Yes	95	1,555	637	919	9,468	21,109	21,905	1,314

Butler, OH	Other	32	2,269	563	1,706	10,636	16,661	12,734	1,105

Greene, OH	Yes	14	984	265	719	1,798	8,499	5,712	682

Clark, OH	No	5	931	288	643	426	5,533	7,427	921

The Montgomery County emissions are moderate, but are the highest in the
Dayton area.  Clark and Greene Counties have lower emissions.  Butler
County is in the Dayton area.

Table 2 provides the data for CES weighting factors.  The trajectory
factors are used in CES calculations to account for seasonal
meteorology.  For the top 10% of days in both the cold and warm seasons,
wind trajectories were run for a 48 hour period preceding the high
monitor reading.  The amount of time the air mass was over a county
within the mixing height was calculated.  The values were scaled so that
the maximum value is 100.  Thus, the county that is most likely to be
upwind of a monitor on a high concentration day in a season is given a
score of 100.  The scores for the other counties will reflect the
relative likelihood of being upwind.  As the concentration of a
pollutant will decrease as it goes further downwind, a distance
weighting factor is also used in calculating the CES.  The distance
factor listed on Table 2 provides the distance from the center of a
county to the center of the violating county.  If a county is violating,
the distance used is the average distance from the center to the county
line.

  Table 2.  CES Factor Data

County	CES	Trajectory Factor- Cold	Trajectory Factor- Warm	Distance (mi)

Montgomery	95	100	96	12.1

Butler	32	63	75	26.3

Greene	14	93	100	22.2

Clark	5	86	79	28.3

Factor 2:  Air quality data 

This factor considers the 24-hour PM2.5 design values (in µg/m3) for
air quality monitors in counties in the Dayton area based on data for
the 2005-2007 period.  A monitor’s design value indicates whether that
monitor attains a specified air quality standard.  The 24-hour PM2.5
standards are met when the 3-year average of a monitor’s 98th
percentile values are 35 µg/m3 or less.  A design value is only valid
if minimum data completeness criteria are met.

The 24-hour PM2.5 design values for counties in the Dayton area are
shown in Table 3.  Clark and Montgomery Counties both have design values
that exceed the 2006 standards.  Greene County meets the standards. 
However, the absence of a violating monitor alone is not a sufficient
reason to eliminate counties as candidates for nonattainment status. 
Each county has been evaluated based on the weight of evidence of the
nine factors and other relevant information.  

	Table 3.  Air Quality Data

County	State 

Recommended

Nonattainment?	Design Values

2004-2006	Design Values

2005-2007

Montgomery, OH	Yes	36	37

Greene, OH	Yes	31	33

Clark, OH	No	35	36

For purposes of its review, EPA used data available from the Chemical
Speciation Network and the Interagency Monitoring of Protected Visual
Environments (IMPROVE) network to estimate the composition of fine
particle mass on days with the highest fine particle concentrations. 
Analysis of these data indicates that the days with the highest fine
particle concentrations in the Dayton area occur about 67% in the warm
season and 33% in the cool season.  In the warm season, the average
chemical composition of the highest days is 81% sulfate, no nitrate, 17%
carbon, and 2% crustal.  In the cool season, the average chemical
composition of the highest days is 40% sulfate, 29% nitrate, 28% carbon,
and 3% crustal.  These data indicate that sources of SO2, NOx, and
direct PM2.5 emissions contribute to violations in the area.

Factor 3: Population density and degree of urbanization (including
commercial development)

Table 4 shows the 2005 population for each county in the area being
evaluated, as well as the population density for each county in that
area.  Population data gives an indication of whether it is likely that
population-based emissions might contribute to violations of the 24-hour
PM2.5 standards. 

Table 4.  Population

County	State Recommended Nonattainment?	2005 Population	2005 Population
Density (pop/sq mi)

Montgomery, OH	Yes	   545,603 	1176

Greene, OH	Yes	   151,823 	365

Clark, OH	No	   141,908 	352

Montgomery County has the largest population in the area.  The three
area counties all have moderate populations.

Factor 4: Traffic and commuting patterns 

This factor considers the number of commuters in each county who drive
to another county within the Dayton area, the percent of total commuters
in each county who commute within the area, as well as the total Vehicle
Miles Traveled (VMT) for each county in millions of miles (see Table 5).
 A county with numerous commuters is generally an integral part of an
urban area and is likely contributing to fine particle concentrations in
the area.  

Table 5.  Traffic and Commuting Patterns

County	State Recommended Nonattainment?	2005 VMT

(106 mi)	Number Commuting to any violating counties 	Percent

Commuting to any violating counties 	Number Commuting within statistical
area 	Percent

Commuting within statistical area 

Montgomery, OH	Yes	   5,533 	216,330 	84 	    244,900 	          95 

Greene, OH	Yes	   1,515 	27,800 	38 	      68,710 	          95 

Clark, OH	No	   1,584 	53,090 	81 	      61,110 	          93 

Butler, OH	other	   3,059 	95,200 	60 	        5,480 	            3 

The listing of counties on Table 5 reflects a ranking based on the
number of people commuting to other counties.  The counties in bold type
are all in the Dayton nonattainment area for the 1997 PM2.5 NAAQS.  The
percent commuting within the Dayton statistical area is at least 93% for
all three counties.  This indicates the counties are highly integrated. 
The commuting data also show minimal commuting from Butler County, which
is the nearest portion of the Cincinnati area.  Thus, these data support
treating Cincinnati and Dayton as separate urban areas.

Note:  The 2005 VMT data used for tables 5 and 6 of the technical
analysis have been derived using methodology such as that described in
"Documentation for the 2005 Mobile National Emissions Inventory, Version
2," December 2008, prepared for the Emission Inventory Group, U.S. EPA. 
This document may be found at:   HYPERLINK
"ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/20
05_mobile_nei_version_2_report.pdf" 
ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/200
5_mobile_nei_version_2_report.pdf .

Factor 5:  Growth rates and patterns  

This factor considers population growth for 2000-2005 and growth in
vehicle miles traveled for 1996-2005 for counties in Dayton area, as
well as patterns of population and VMT growth.  A county with rapid
population or VMT growth is generally an integral part of an urban area
and likely to be contributing to fine particle concentrations in the
area.

Table 6 below shows population, population growth, VMT, and VMT growth
for counties that are included in the Dayton area.  Counties are listed
in descending order based on VMT growth between 1996 and 2005.

Table 6.  Population and VMT Growth and Percent Change.

County	Population (2005)	Population % change (2000-2005)	2005 VMT

(106 mi)	VMT

% change

(1996-2005)

Greene, OH	    151,823 	2 	     1,515 	           19 

Clark, OH	    141,908 	-2	     1,584 	           12 

Montgomery, OH	    545,603 	-2	     5,533 	            -2

The population change is limited for all three area counties.  The VMT
declined slightly from 1996 to 2005 in Montgomery County.  During that
period, the VMT grew by moderate amounts in Clark and Greene Counties. 
Thus, the distribution of population and VMT is not expected to change
significantly over the SIP planning time horizon.

Factor 6:  Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service
instruments and other meteorological monitoring sites in the area.  Wind
direction and wind speed data for 2005-2007 were analyzed, with an
emphasis on “high PM2.5 days” for each of two seasons, an
October-April “cold” season and a May-September “warm” season. 
These high days are defined as days where any FRM or FEM air quality
monitors had 24-hour PM2.5 concentrations above 95% on a frequency
distribution curve of PM2.5 24-hour values. 

 values by color; days exceeding 35 μg/m3 are denoted with a red or
black icon.  A dot indicates the day occurred in the warm season; a
triangle indicates the day occurred in the cool season.  The center of
the figure indicates the location of the air quality monitoring site,
and the location of the icon in relation to the center indicates the
direction from which the wind was blowing on that day.  An icon that is
close to the center indicates a low average wind speed on that day. 
Higher wind speeds are indicated when the icon is further away from the
center.

The pollution rose for the Dayton area is provided as Figure 2.  Winds
on high concentration days come from a variety of directions.  So, it is
appropriate to consider counties in all directions from the violations

 

Figure 2

Note:  the meteorology factor is also considered in each county’s
Contributing Emissions Score because the method for deriving this metric
included an analysis of trajectories of air masses for high PM2.5 days.

Factor 7:  Geography/topography (mountain ranges or other air basin
boundaries)

The geography/topography analysis evaluates the physical features of the
land that might have an effect on the air shed and, therefore, on the
distribution of PM2.5 over the area.

The Dayton 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 the
decision-making process.

Factor 8:  Jurisdictional boundaries

In evaluating the jurisdictional boundary factor, EPA gave special
consideration to areas that were already designated nonattainment in
2005 for violating the 1997 fine particle standards.  Analysis of
chemical composition data in these areas indicates that the same
components that make up most of the PM2.5 mass in the area on an annual
average basis such as sulfate and direct PM2.5 carbon in many eastern
areas also are key contributors to the PM2.5 mass on days exceeding the
24-hour PM2.5 standard.  These data indicate that in many cities, the
same source categories that contribute to violations of the annual
standard also contribute to exceedances of the 24-hour standard.  

EPA has generally concluded that counties that were designated as having
emissions sources contributing to fine particle concentrations which
exceeded the 1997 standards (all areas violated the annual standard, two
also violated the previous 24-hour standard) also contribute to fine
particle concentrations on the highest days.  For this reason, EPA
believes that for most existing nonattainment areas, the nonattainment
area for the 2006 24-hour standard should be the same.  Consideration
also should be given to existing boundaries and organizations as they
may facilitate air quality planning and the implementation of control
measures to attain the standard.  Areas already designated as
nonattainment represent important boundaries for state air quality
planning.

The Miami Valley Regional Planning Commission (MVRPC) is the
Metropolitan Planning Organization (MPO) for the following counties:
Greene, Miami, Montgomery, and portions of Warren.  The MVRPC website is
  HYPERLINK "http://www.mvrpc.org/index.htm" 
http://www.mvrpc.org/index.htm .  The Cincinnati area has a separate
MPO, the Ohio-Kentucky-Indiana Regional Council of Governments which
serves Butler, Warren, Clermont, and Hamilton Counties in Ohio;
Campbell, Kenton, and Boone Counties in Kentucky; and Dearborn County,
Indiana.

The Dayton ozone maintenance area consists of the following counties:
Clark, Greene, Miami, and Montgomery.

The Dayton nonattainment area is identical to the nonattainment area
designated under the 1997 PM2.5 standard, which would facilitate
planning.

Factor 9:  Level of control of emission sources 

Under this factor, the existing level of control of emission sources is
taken into consideration.  The emissions data used by EPA in this
technical analysis and provided in Table 1 under Factor 1 represent
emissions levels taking into account any control strategies implemented
in the Dayton area before 2005 on stationary, mobile, and area sources. 
Data are presented for PM2.5 components that are directly emitted,
carbonaceous PM2.5 and crustal PM2.5, and for pollutants which react in
the atmosphere to form fine particles such as SO2, NOx, VOC, and
ammonia.  

In considering county-level emissions, EPA used data from the 2005
National Emissions Inventory, the most updated version of the national
inventory available at the beginning of the designations process in late
2007.  However, EPA recognized that for certain counties, emissions may
have changed since 2005.  For example, certain power plants or large
sources of emissions in or near this area may have installed emission
controls or otherwise significantly reduced emissions since 2005.  Some
States provided updated information on emissions and emission controls
in their comments to EPA.  EPA considered such additional information in
making final designation decisions.  

With regard to nearby power plants, EPA considered information about
whether a specific plant installed federally enforceable emission
controls by December 2008 resulting in significant emissions reductions.
 A control requirement is considered to be federally-enforceable if it
is required by a State regulation adopted in a State implementation
plan, if it is included in a federally-enforceable Title V operating
permit, or if it is required by a consent decree which also requires the
controls to be included in federally enforceable permit upon termination
of the consent decree.  In making final decisions, EPA also considered
whether a facility would continue to emit pollutants which contribute to
PM2.5 exceedances even after emission controls are operational. 

Ohio did not provide other information regarding power plants or any
other large sources in the Dayton area.

EPA Technical Analysis for Huntington-Ashland, West
Virginia-Kentucky-Ohio 

In the three-state Huntington-Ashland area, part or all of nine counties
are designated nonattainment for the 1997 standards.  The four Ohio
counties included in this nonattainment area are all of Lawrence and
Scioto Counties, Monroe and Sprigg Townships in Adams County, and
Cheshire Township in Gallia County.  Monitors in Scioto County, Ohio,
and Cabell County, West Virginia, are recording violations of the 2006
standards.  Ohio recommended that no portion of the state be included in
the Huntington-Ashland area designated as nonattainment for the 2006
standards.  

EPA believes that several Ohio counties should be part of the
Huntington-Ashland nonattainment area for the 2006 standards.  Scioto
County should be included in the nonattainment area because it is
violating the standard, because it is contributing to the violation
within Scioto County, and because the county’s emissions have a
non-negligible impact on the violation in Cabell County, West Virginia. 
Lawrence County has a substantial fraction of the emissions in the
Huntington-Ashland metropolitan statistical area, the winds very
commonly blow these emissions into Cabell County, and Lawrence County is
immediately adjacent to Cabell County.  

The emissions from Monroe and Sprigg Townships in Adams County and from
Cheshire Township in Gallia County are dominated by emissions from power
plants.  Ohio provided information on the status of emission controls at
these plants.  Some of the emissions have long been controlled with
effective control equipment, some of these emissions have become well
controlled more recently, and some of these emissions are expected to be
controlled within a few years.  The longstanding controls were installed
in response to the acid rain program, and the controls at Stuart Station
in Adams County are mandated by a consent decree, but other controls may
not be required, particularly if the D.C. Circuit Court of appeals
follows its adverse opinion on CAIR with vacatur of that program.  More
importantly, even with existing controls, emissions remain relatively
high in both Adams and Gallia Counties.  Therefore, EPA is including
portions of both of these counties in the nonattainment area. 
Nevertheless, since the emissions in these counties are dominated by the
power plant emissions, and the remainder of the counties can be
considered not to contribute to the violations, EPA is only including
the portions of the counties with the power plant in the nonattainment
area.  Therefore, in Ohio, EPA is only including Monroe and Sprigg
Townships in Adams County and Cheshire Township in Gallia County, along
with Scioto and Lawrence Counties, in the Huntington-Ashland
nonattainment area.

The surrounding Ohio counties have relatively low emissions, and no
other factor warrants their inclusion in the nonattainment area.

Figure 1 is a map of the counties in the nonattainment area and other
relevant information such as the locations and design values of air
quality monitors, and the metropolitan area boundary. 

 

Figure 1

For this area, EPA previously established PM2.5 nonattainment boundaries
for the 1997 PM2.5 NAAQS that included nine full and partial counties,
with four being located in Ohio.

In its May 30, 2008 letter, Ohio recommended that no Ohio counties be
designated as “nonattainment” for the 2006 24-hour PM2.5 standard
based on air quality data from 2005-2007.  These data are from Federal
Reference Method (FRM) monitors located in the state.

In August 2008, EPA notified Ohio of its intended designations.  In this
letter, EPA also requested that if the State wished to provide comments
on EPA’s intended designation, it should do so by October 20, 2008. 
EPA stated that it would consider any additional information (e.g., on
power plants or partial county areas) provided by the state in making
final decisions on the designations.  

Based on EPA's technical analysis described below, EPA designated four
full or partial Ohio counties as nonattainment for the 24-hour PM2.5
air-quality standard as part of the Huntington-Ashland nonattainment
area, based upon currently available information.

EPA responded to Ohio’s comments in the State Response to Comments
document.

The following is a review of data for relevant factors for the Ohio
portion of the Huntington-Ashland, West Virginia-Kentucky-Ohio area. 

Factor 1:  Emissions data

For this factor, EPA evaluated county level emission data for the
following PM2.5 components and precursor pollutants:  “PM2.5 emissions
total,” “PM2.5 emissions carbon,” “PM2.5 emissions other,”
“SO2,” “NOx,” “VOCs,” and “NH3.”  “PM2.5 emissions
total” represents direct emissions of PM2.5 and includes: “PM2.5
emissions carbon,” “PM2.5 emissions other”, primary sulfate (SO4),
and primary nitrate.  (Although primary sulfate and primary nitrate,
which are emitted directly from stacks rather than forming in
atmospheric reactions with SO2 and NOx, are part of “PM2.5 emissions
total,” they are not shown in Table 1 as separate items).  “PM2.5
emissions carbon” represents the sum of organic carbon (OC) and
elemental carbon (EC) emissions, and “PM2.5 emissions other”
represents other inorganic particles (crustal).  Emissions of SO2 and
NOx, which are precursors of the secondary PM2.5 components sulfate and
nitrate, are also considered.  VOCs (volatile organic compounds) and NH3
(ammonia) are also potential PM2.5 precursors and are included for
consideration. 

Emissions data were derived from the 2005 National Emissions Inventory
(NEI), version 1.  See
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

EPA also considered the Contributing Emissions Score (CES) for each
county.  The CES is a metric that takes into consideration emissions
data, meteorological data, and air quality monitoring information to
provide a relative ranking of counties in and near an area.  Note that
this metric is not the exclusive manner for considering data for these
factors.  A more detailed description can be found at
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html#C.

Table 1 shows emissions of PM2.5 and precursor pollutants components
(given in tons per year) and the CES for violating and potentially
contributing counties in the Huntington-Ashland area.  Counties that are
part of the Huntington-Ashland nonattainment area for the 1997 PM2.5
NAAQS are shown in boldface.  Counties are listed in descending order by
CES.

Table 1.  PM2.5 24-hour Component Emissions, and CESs. 

County	State Recommended Nonattainment?	CES	PM2.5

emissions 

total	PM2.5

emissions 

carbon	PM2.5

emissions 

other	SO2

	NOx

	VOCs

	NH3

Cabell, WV	No	100	1,082	434	649	4,355	10,644	5,878	181

Gallia, OH	No	100	7,087	499	6,588	100,704	59,035	1,939	327

Putnam, WV	Other	92	4,838	468	4,370	113,590	37,387	3,117	106

Lawrence, OH	No	78	1,078	672	406	573	3,769	4,847	316

Scioto, OH	No	58	775	416	359	555	4,981	4,111	1,349

Mason, WV	No	54	3,528	305	3,222	82,856	24,561	2,496	237

Adams, OH	No	46	5,970	494	5,476	126,316	33,822	1,918	837

Boyd, KY	No	44	1,729	412	1,317	10,501	10,123	5,762	477

Wayne, WV	No	33	657	446	210	1,041	7,619	2,577	70

Lawrence, KY	No	27	2,567	199	2,368	50,239	13,761	932	90

Greenup, KY	No	24	319	151	169	2,183	4,102	1,694	155

Kanawha, WV	Other	15	2,016	857	1,159	21,633	23,985	15,652	527

In Ohio, Adams and Gallia Counties have high emissions.  The sulfur
dioxide and oxides of nitrogen emissions are very large.  The emissions
are not as large in Lawrence and Scioto Counties, but they have high
CES.  This information suggests that emissions from all four of these
counties are contributing to the PM2.5 violations in the
Huntington-Ashland area.  This conclusion is supported by other
information such as the geographic proximity of the sources and the
meteorology of this area.

Table 2 provides the data for CES weighting factors.  The trajectory
factors are used in CES calculations to account for seasonal
meteorology.  For the top 10% of days in both the cold and warm seasons,
wind trajectories were run for a 48 hour period preceding the high
monitor reading.  The amount of time the air mass was over a county
within the mixing height was calculated.  The values were scaled so that
the maximum value is 100.  Thus, the county that is most likely to be
upwind of a monitor on a high concentration day in a season is given a
score of 100.  The scores for the other counties will reflect the
relative likelihood of being upwind.  As the concentration of a
pollutant will decrease as it goes further downwind, a distance
weighting factor is also used in calculating the CES.  The distance
factor listed on Table 2 provides the distance from the center of a
county to the center of the violating county.  If a county is violating,
the distance used is the average distance from the center to the county
line.

  Table 2.  CES Factor Data.

County	CES	Trajectory Factor- Cold	Trajectory Factor- Warm	Distance (mi)

Cabell, WV	100	100	85	9

Gallia, OH	100	70	82	28

Putnam, WV	92	66	54	21.1

Lawrence, OH	78	96	100	21.3

Scioto, OH	58	46	57	45.6

Mason, WV	54	62	66	27.6

Adams, OH	46	20	28	71.2

Boyd, KY	44	100	91	23.3

Wayne, WV	33	89	66	21.5

Lawrence, KY	27	78	58	35

Greenup, KY	24	71	74	38.3

Kanawha, WV	15	34	23	41.4

Factor 2:  Air quality data 

This factor considers the 24-hour PM2.5 design values (in µg/m3) for
air quality monitors in counties in the Huntington-Ashland area based on
data for the 2005-2007 period.  A monitor’s design value indicates
whether that monitor attains a specified air quality standard.  The
24-hour PM2.5 standards are met when the 3-year average of a monitor’s
98th percentile values are 35 µg/m3 or less.  A design value is only
valid if minimum data completeness criteria are met.

The 24-hour PM2.5 design values for counties in the Huntington-Ashland
area are shown in Table 3.

	Table 3.  Air Quality Data

County	State 

Recommended

Nonattainment?	Design Values

2004-2006

	Design Values

2005-2007

Cabell, WV	No	34	37

Gallia, OH	No	0	0

Lawrence, OH	No	34	35

Scioto, OH	No	33	36

Mason, WV	No	0	0

Adams, OH	No	0	0

Boyd, KY	No	32	34

Wayne, WV	No	0	0

Lawrence, KY	No	0	0

Greenup, KY	No	0	0

Scioto County, Ohio has a 2005 to 2007 design value that exceeds the
2006 standards and thus must be included in the nonattainment area. 
Cabell County in West Virginia also violated the standard.  Lawrence
County, Ohio attained the 2006 standards.  Adams and Gallia Counties in
Ohio do not have PM2.5 air quality monitoring data.  However, the
absence of a violating monitor alone is not a sufficient reason to
eliminate counties as candidates for nonattainment status.  Each county
has been evaluated based on the weight of evidence of the nine factors
and other relevant information.  

For purposes of its review, EPA used data available from the Chemical
Speciation Network and the Interagency Monitoring of Protected Visual
Environments (IMPROVE) network to estimate the composition of fine
particle mass on days with the highest fine particle concentrations. 
Analysis of these data indicates that the days with the highest fine
particle concentrations in the Huntington-Ashland area occur about 94%
in the warm season and 6% in the cool season.  In the warm season, the
average chemical composition of the highest days is 70% sulfate, no
nitrate, 27% carbon, and 3% crustal.  In the cool season, the average
chemical composition of the highest days is 58% sulfate, 4% nitrate, 34%
carbon, and 4% crustal.  These data indicate that sources of SO2, NOx,
and direct PM2.5 emissions contribute to violations in the area.

Factor 3: Population density and degree of urbanization (including
commercial development)

Table 4 shows the 2005 population for each county in the area being
evaluated, as well as the population density for each county in that
area.  Population data gives an indication of whether it is likely that
population-based emissions might contribute to violations of the 24-hour
PM2.5 standards. 

Table 4.  Population

County	State Recommended Nonattainment?	2005 Population	2005 Population
Density (pop/mi2)

Cabell, WV	No	     93,988 	327

Scioto, OH	No	     76,506 	124

Lawrence, OH	No	     62,946 	134

Boyd, KY	No	     49,359 	305

Wayne, WV	No	     41,959 	82

Greenup, KY	No	     37,206 	105

Gallia, OH	No	     31,241 	68

Adams, OH	No	     28,454 	49

Mason, WV	No	     25,763 	58

Lawrence, KY	No	     16,162 	39

The county populations in the Huntington-Ashland area are all moderate
to low.  In Ohio, Scioto and Lawrence Counties have second and third
largest populations in the area which support including them in the
nonattainment area.  Adams and Gallia Counties both have low
populations.  The low population of Adams and Gallia Counties and the
fact that virtually all the emissions in these counties are emitted in
the townships with major power plants supports applying a nonattainment
designation to just the townships within these counties that contain the
power plants.

Factor 4: Traffic and commuting patterns 

This factor considers the number of commuters in each county who drive
to another county within the Huntington-Ashland area, the percent of
total commuters in each county who commute within the area, as well as
the total Vehicle Miles Traveled (VMT) for each county in millions of
miles (see Table 5).  A county with numerous commuters is generally an
integral part of an urban area and is likely contributing to fine
particle concentrations in the area.  

Table 5.  Traffic and Commuting Patterns

County	State Recommended Nonattainment?	2005 VMT

(106 mi)	Number Commuting to any violating counties 	Percent

Commuting to any violating counties 	Number Commuting into statistical
area 	Percent

Commuting into statistical area 

Cabell, WV	No	 1,230 	34,670 	86 	      35,460 	          88 

Lawrence, OH	No	           650	7,970 	35 	      21,160 	          92 

Boyd, KY	No	           574 	1,380 	7 	      17,580 	          93 

Wayne, WV	No	        438 	7,170 	46 	      14,040 	          90 

Greenup, KY	No	        371 	1,770 	13 	      11,130 	          83 

Scioto, OH	No	        591 	22,040 	78 	        1,330 	            5 

Lawrence, KY	No	        159 	250 	5 	           920 	          19 

Mason, WV	No	        249 	1,080 	12 	           670 	            7 

Gallia, OH	No	        247 	300 	3 	           330 	            3 

Adams, OH	No	        283 	130 	1 	             20 	            0 

Lawrence County, Ohio has a high percent commuting within the
metropolitan statistical area and a moderate percent commuting into
violating counties, because the county is in the metropolitan
statistical area and is not a violating county.  Conversely, Scioto
County has a low percent commuting into the metropolitan statistical
area and a high percent commuting into violating counties, reflecting
the fact that Scioto County is not part of the metropolitan statistical
area but is a violating county.  Both counties would be included in the
designated area based on this factor.  The commuting figures are low for
both Adams and Gallia Counties in Ohio, suggesting that they were good
candidates for partial county designations. 

Note:  The 2005 VMT data used for tables 5 and 6 of the technical
analysis have been derived using methodology such as that described in
"Documentation for the 2005 Mobile National Emissions Inventory, Version
2," December 2008, prepared for the Emission Inventory Group, U.S. EPA. 
This document may be found at:   HYPERLINK
"ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/20
05_mobile_nei_version_2_report.pdf" 
ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/200
5_mobile_nei_version_2_report.pdf .

Factor 5:  Growth rates and patterns  

This factor considers population growth for 2000-2005 and growth in
vehicle miles traveled for 1996-2005 for counties in Huntington-Ashland
area, as well as patterns of population and VMT growth.  A county with
rapid population or VMT growth is generally an integral part of an urban
area and likely to be contributing to fine particle concentrations in
the area.

Table 6 below shows population, population growth, VMT, and VMT growth
for counties that are included in the Huntington-Ashland area.  Counties
are listed in descending order based on VMT growth between 1996 and
2005.

Table 6.  Population and VMT Growth and Percent Change.

County	Population (2005)	Population % change (2000-2005)	2005 VMT

(106 mi)	VMT

% change

(1996-2005)

Wayne, WV	     41,959 	-2	        438 	          47 

Cabell, WV	     93,988 	-3	      1,230 	          41 

Mason, WV	     25,763 	-1	        249 	          36 

Greenup, KY	     37,206 	1 	        371 	          23 

Boyd, KY	     49,359 	-1	        574 	          16 

Lawrence, KY	     16,162 	4 	        159 	           11

Lawrence, OH	     62,946 	1 	        650 	            9 

Adams, OH	     28,454 	4 	        283 	            7 

Gallia, OH	     31,241 	0 	        247 	            0 

Scioto, OH	     76,506 	-3	        591 	           -3 

Several of the Huntington-Ashland area counties encountered strong VMT
growth from 1996 to 2005.  In Ohio, the VMT growth was limited with
Adams and Lawrence Counties having modest increases.  The VMT did not
change in Gallia County.  It declined slightly in Scioto County.  The
populations of the area counties remained stable from 2000 to 2005 with
small changes being observed.  The Ohio counties in the area followed
this pattern.  Adams County, Ohio matched Lawrence County, Kentucky with
4% population growth as the largest changes in the area.  These changes
do not suggest any significant shifts in the distribution of population
or VMT to be considered in the designations process.  Thus, this factor
was not significant in determining the boundary of the nonattainment
area.

Factor 6:  Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service
instruments and other meteorological monitoring sites in the area.  Wind
direction and wind speed data for 2005-2007 were analyzed, with an
emphasis on “high PM2.5 days” for each of two seasons, an
October-April “cold” season and a May-September “warm” season. 
These high days are defined as days where any FRM or FEM air quality
monitors had 24-hour PM2.5 concentrations above 95% on a frequency
distribution curve of PM2.5 24-hour values. 

 values by color; days exceeding 35 μg/m3 are denoted with a red or
black icon.  A dot indicates the day occurred in the warm season; a
triangle indicates the day occurred in the cool season.  The center of
the figure indicates the location of the air quality monitoring site,
and the location of the icon in relation to the center indicates the
direction from which the wind was blowing on that day.  An icon that is
close to the center indicates a low average wind speed on that day. 
Higher wind speeds are indicated when the icon is further away from the
center.

The pollution rose for the critical Cabell County monitoring site is
provided as Figure 2, and the pollution rose for the Scioto County
monitoring site is provided as Figure 3.  Winds on high concentration
days show a slight tendency to come from the north or northeast or the
south or southwest, although on some high concentration days winds come
from other directions as well.  Therefore, it is appropriate to consider
counties in all directions from the violations.  The pollution roses
indicate that any nearby surrounding counties with high emissions would
be contributing to the violating monitors.

 

Figure 2

Figure 3

Note:  the meteorology factor is also considered in each county’s
Contributing Emissions Score because the method for deriving this metric
included an analysis of trajectories of air masses for high PM2.5 days.

Factor 7:  Geography/topography (mountain ranges or other air basin
boundaries)

The geography/topography analysis evaluates the physical features of the
land that might have an effect on the air shed and, therefore, on the
distribution of PM2.5 over the area.

The Huntington-Ashland 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 the decision-making process.

Factor 8:  Jurisdictional boundaries

In evaluating the jurisdictional boundary factor, EPA gave special
consideration to areas that were already designated nonattainment in
2005 for violating the 1997 fine particle standards.  Analysis of
chemical composition data in these areas indicates that the same
components that make up most of the PM2.5 mass in the area on an annual
average basis such as sulfate and direct PM2.5 carbon in many eastern
areas also are key contributors to the PM2.5 mass on days exceeding the
24-hour PM2.5 standard.  These data indicate that in many cities, the
same source categories that contribute to violations of the annual
standard also contribute to exceedances of the 24-hour standard.  

EPA has generally concluded that counties that were designated as having
emissions sources contributing to fine particle concentrations which
exceeded the 1997 standards (all areas violated the annual standard, two
also violated the previous 24-hour standard) also contribute to fine
particle concentrations on the highest days.  For this reason, EPA
believes that for most existing nonattainment areas, the nonattainment
area for the 2006 24-hour standard should be the same.  Consideration
also should be given to existing boundaries and organizations as they
may facilitate air quality planning and the implementation of control
measures to attain the standard.  Areas already designated as
nonattainment represent important boundaries for state air quality
planning.

The KYOVA Interstate Planning Commission is the Metropolitan Planning
Organization (MPO) for Lawrence County, OH.  KYOVA website:
http://www.state.wv.us/kyova/.

There are no counties in the Ohio portion of the Huntington-Ashland
maintenance area for the ozone standard.  Boyd County, Kentucky and
Cabell and Wayne Counties in West Virginia comprise the ozone
maintenance area. 

The Huntington-Ashland nonattainment area is identical to the
nonattainment area designated under the 1997 PM2.5 standard, which will
facilitate air quality planning.  

Factor 9:  Level of control of emission sources 

Under this factor, the existing level of control of emission sources is
taken into consideration.  The emissions data used by EPA in this
technical analysis and provided in Table 1 under Factor 1 represent
emissions levels taking into account any control strategies implemented
in the Huntington-Ashland area before 2005 on stationary, mobile, and
area sources.  Data are presented for PM2.5 components that are directly
emitted, carbonaceous PM2.5 and crustal PM2.5, and for pollutants which
react in the atmosphere to form fine particles such as SO2, NOx, VOC,
and ammonia.  

In considering county-level emissions, EPA used data from the 2005
National Emissions Inventory, the most updated version of the national
inventory available at the beginning of the designations process in late
2007.  However, EPA recognized that for certain counties, emissions may
have changed since 2005.  For example, certain power plants or large
sources of emissions in or near this area may have installed emission
controls or otherwise significantly reduced emissions since 2005.  Some
States provided updated information on emissions and emission controls
in their comments to EPA.  EPA considered such additional information in
making final designation decisions.  

With regard to nearby power plants, EPA considered information about
whether a specific plant installed federally enforceable emission
controls by December 2008 resulting in significant emissions reductions.
 A control requirement is considered to be federally-enforceable if it
is required by a State regulation adopted in a State implementation
plan, if it is included in a federally-enforceable Title V operating
permit, or if it is required by a consent decree which also requires the
controls to be included in federally enforceable permit upon termination
of the consent decree.  In making final decisions, EPA also considered
whether a facility would continue to emit pollutants which contribute to
PM2.5 exceedances even after emission controls are operational. 

Ohio provided information on the status of emission controls at four
plants in the Huntington-Ashland area.  Some of the emissions have long
been controlled with effective control equipment, some of the emissions
have become well controlled more recently, and some of these emissions
are expected to be controlled within a few years.  In Gallia County,
Gavin Station has long had control equipment reducing SO2 emissions and
more recently has installed controls to reduce NOx emissions, but
emissions remain high.  Also in Gallia County, Kyger Creek Station is
expected to install SO2 emission controls by 2010, but current emissions
remain high.  In Adams County, Stuart Station is subject to a consent
decree requiring future control of both SO2 and NOx.  Also in Adams
County, Killen Station has installed control equipment both for SO2 and
for NOx, although EPA is aware of no enforceable requirement for the
company to operate this equipment, particularly if the D.C. Circuit
Court of Appeals vacates CAIR.  More importantly, even with these
controls, total emissions from these plants remain somewhat high.  The
company, in comments submitted in response to EPA solicitation of public
comments, stated that emissions with control are still 7200 tons per
year of SO2 and 20,000 tons per year of NOx.  Company emission reports
posted on EPA’s acid rain program web site suggest a comparable
controlled SO2 emission rate, but data on EPA’s NOx budget program web
site suggests a controlled emission rate from the two plants adding to
4800 tons for the five month ozone season, which if controls were
operated full year would suggest an annual emission rate of 11,400 tons
per year.  In either case, the emissions from this facility even with
controls are sufficient that coupled with meteorology EPA is judging
that these facilities contribute to violations in Scioto and Cabell
Counties.  Also of concern is that no permit or other enforceable
document requires operation of the NOx control equipment year round at
Killen Station.  As noted above EPA must base designations on current
conditions notwithstanding any planned future emissions controls. 
Therefore, EPA is including Monroe and Sprigg Townships in Adams County
and Cheshire Township in Gallia County, along with Scioto and Lawrence
Counties, in the Huntington-Ashland nonattainment area.  However, since
neither Adams nor Gallia rank high for any factor other than emissions,
EPA has designated only the townships where the power plant emissions
are located.

EPA has responded in detail to all of the comments submitted by Ohio in
the Response to State Comments document in the docket for this
rulemaking.

EPA Technical Analysis for Parkersburg-Marietta, West Virginia-Ohio 

Parkersburg-Marietta is a two-state nonattainment area.  Under the 1997
standards, Washington County, Ohio along with Pleasants (partial) and
Wood Counties, West Virginia comprised the nonattainment area.  A
violation is being observed in Wood County, West Virginia.  The analysis
of the Parkersburg-Marietta area for designations under the 2006
standards examined the entire area, though this discussion only
addresses the Ohio portion of the area.  In a May 30, 2008 letter, Ohio
recommended retaining Washington County in the Parkersburg-Marietta
nonattainment area.

EPA agrees with Ohio’s recommendation for this area.  The emissions
from Washington County are high.  Sulfur dioxide emissions are
especially high because of the two power plants in the county.  Emission
controls are limited for these facilities.  The population and traffic
in Washington County is comparable to the rest of the
Parkersburg-Marietta area.  There is no air quality monitoring in
Washington County.  

The surrounding Ohio counties have relatively low emissions, and no
other factor warrants their inclusion in the nonattainment area.

Figure 1 is a map of the counties in the nonattainment area and other
relevant information such as the locations and design values of air
quality monitors, and the metropolitan area boundary. 

 

Figure 1

For this area, EPA previously established PM2.5 nonattainment boundaries
for the 1997 PM2.5 NAAQS that included three full and partial counties
including Washington County in Ohio.  

In its May 30, 2008 letter, Ohio recommended the same Ohio county be
designated as “nonattainment” for the 2006 24-hour PM2.5 standard
based on air quality data from 2005-2007.  These data are from Federal
Reference Method (FRM) monitors located in the state.

In August 2008, EPA notified Ohio of its intended designations.  In this
letter, EPA also requested that if the State wished to provide comments
on EPA’s intended designation, it should do so by October 20, 2008. 
EPA stated that it would consider any additional information (e.g., on
power plants or partial county areas) provided by the state in making
final decisions on the designations.  

Based on EPA's technical analysis described below, EPA designated
Washington County, Ohio and a full and a partial county in West Virginia
nonattainment for the 24-hour PM2.5 air-quality standard as part of the
Parkersburg nonattainment area, based upon currently available
information.

The following is a review of data for relevant factors for the Ohio
portion of the Parkersburg, West Virginia-Ohio area. 

Factor 1:  Emissions data

For this factor, EPA evaluated county level emission data for the
following PM2.5 components and precursor pollutants:  “PM2.5 emissions
total,” “PM2.5 emissions carbon,” “PM2.5 emissions other,”
“SO2,” “NOx,” “VOCs,” and “NH3.”  “PM2.5 emissions
total” represents direct emissions of PM2.5 and includes: “PM2.5
emissions carbon,” “PM2.5 emissions other”, primary sulfate (SO4),
and primary nitrate.  (Although primary sulfate and primary nitrate,
which are emitted directly from stacks rather than forming in
atmospheric reactions with SO2 and NOx, are part of “PM2.5 emissions
total,” they are not shown in Table 1 as separate items).  “PM2.5
emissions carbon” represents the sum of organic carbon (OC) and
elemental carbon (EC) emissions, and “PM2.5 emissions other”
represents other inorganic particles (crustal).  Emissions of SO2 and
NOx, which are precursors of the secondary PM2.5 components sulfate and
nitrate, are also considered.  VOCs (volatile organic compounds) and NH3
(ammonia) are also potential PM2.5 precursors and are included for
consideration. 

Emissions data were derived from the 2005 National Emissions Inventory
(NEI), version 1.  See
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

EPA also considered the Contributing Emissions Score (CES) for each
county.  The CES is a metric that takes into consideration emissions
data, meteorological data, and air quality monitoring information to
provide a relative ranking of counties in and near an area.  Note that
this metric is not the exclusive manner for considering data for these
factors.  A more detailed description can be found at
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html#C.

Table 1 shows emissions of PM2.5 and precursor pollutants components
(given in tons per year) and the CES for violating and potentially
contributing counties in the Parkersburg-Marietta area.  Counties that
are part of the Parkersburg-Marietta nonattainment area for the 1997
PM2.5 NAAQS are shown in boldface.  Counties are listed in descending
order by CES.

Table 1.  PM2.5 24-hour Component Emissions, and CES 

County	State Recommended Nonattainment?	CES	PM2.5

emissions 

total	PM2.5

emissions 

carbon	PM2.5

emissions 

other	SO2

	NOx

	VOCs

	NH3

Washington, OH	Yes	100	8,286	741	7,545	164,357	24,331	5,194	1,344

Wood, WV	No	54	977	421	557	6,243	5,866	6,295	200

Pleasants, WV	No	16	1,851	144	1,706	62,011	14,912	1,462	112

Athens, OH	No	7	465	228	236	1,459	3,275	2,352	290

Jackson, WV	No	6	817	188	629	3,326	3,036	2,327	164

Meigs, OH	No	5	321	155	168	338	2,161	1,165	834

The emissions and CES of Washington County, Ohio are the largest in the
area.  The emissions and CES of Athens and Meigs Counties, Ohio are well
below the values of counties designated nonattainment for the 1997 PM2.5
standards.   

Table 2 provides the data for CES weighting factors.  The trajectory
factors are used in CES calculations to account for seasonal
meteorology.  For the top 10% of days in both the cold and warm seasons,
wind trajectories were run for a 48 hour period preceding the high
monitor reading.  The amount of time the air mass was over a county
within the mixing height was calculated.  The values were scaled so that
the maximum value is 100.  Thus, the county that is most likely to be
upwind of a monitor on a high concentration day in a season is given a
score of 100.  The scores for the other counties will reflect the
relative likelihood of being upwind.  As the concentration of a
pollutant will decrease as it goes further downwind, a distance
weighting factor is also used in calculating the CES.  The distance
factor listed on Table 2 provides the distance from the center of a
county to the center of the violating county.  If a county is violating,
the distance used is the average distance from the center to the county
line.  The cold season trajectory factors were not calculated for the
Parkersburg area.

  Table 2.  CES Factor Data

County	CES	Trajectory Factor- Cold	Trajectory Factor- Warm	Distance (mi)

Washington, OH	100

85	14.7

Wood, WV	34

100	10.7

Pleasants, WV	19

75	21.5

Athens, OH	4

77	32

Jackson, WV	4

66	29

Meigs, OH	3

78	32.1

Factor 2:  Air quality data 

This factor considers the 24-hour PM2.5 design values (in µg/m3) for
air quality monitors in counties in the Parkersburg-Marietta area based
on data for the 2005-2007 period.  A monitor’s design value indicates
whether that monitor attains a specified air quality standard.  The
24-hour PM2.5 standards are met when the 3-year average of a monitor’s
98th percentile values are 35 µg/m3 or less.  A design value is only
valid if minimum data completeness criteria are met.

The 24-hour PM2.5 design values for counties in the Parkersburg-Marietta
area are shown in Table 3.

	Table 3.  Air Quality Data

County	State 

Recommended

 Nonattainment?	Design Values

2004-06

(µg/m3)

	Design Values

2005-07

(µg/m3)

Washington, OH	Yes	0	0

Wood, WV	No	35	37

Pleasants, WV	No	0	0

Athens, OH	No	32	33

Jackson, WV	No	0	0

Meigs, OH	No	0	0

A violation of the 2006 PM2.5 standards occurred in the West Virginia
portion of the Parkersburg-Marietta area.  Wood County, West Virginia
has a 2005-2007 design value above the air quality standards.  Athens
County, Ohio meets the standards.  There is no fine particulate air
quality monitoring data for Meigs or Washington Counties, Ohio. 
However, the absence of a violating monitor alone is not a sufficient
reason to eliminate counties as candidates for nonattainment status. 
Each county has been evaluated based on the weight of evidence of the
nine factors and other relevant information.

For purposes of its review, EPA used data available from the Chemical
Speciation Network and the Interagency Monitoring of Protected Visual
Environments (IMPROVE) network to estimate the composition of fine
particle mass on days with the highest fine particle concentrations. 
Analysis of these data indicates that the days with the highest fine
particle concentrations in the Parkersburg area occur about 100% in the
warm season and 0% in the cool season.  In the warm season, the average
chemical composition of the highest days is 72% sulfate, no nitrate, 24%
carbon, and 3% crustal.  In the cool season, the average chemical
composition of the highest days is 34% sulfate, 34% nitrate, 29% carbon,
and 3% crustal.  These data indicate that sources of SO2, NOx, and
direct PM2.5 emissions contribute to violations in the area.

Factor 3: Population density and degree of urbanization (including
commercial development)

Table 4 shows the 2005 population for each county in the area being
evaluated, as well as the population density for each county in that
area.  Population data gives an indication of whether it is likely that
population-based emissions might contribute to violations of the 24-hour
PM2.5 standards. 

Table 4.  Population

County	State Recommended Nonattainment?	2005 Population	2005 Population
Density (pop/sq mi)

Washington, OH	Yes	     62,155 	98

Wood, WV	No	     86,881 	231

Pleasants, WV	No	       7,329 	54

Athens, OH	No	     62,028 	121

Jackson, WV	No	     28,306 	60

Meigs, OH	No	     23,179 	54

The population of Washington County, Ohio is slightly smaller than Wood
County, West Virginia.  Athens County, Ohio has a similar population to
Washington County, Ohio.  Meigs County, Ohio has a low population.

Factor 4: Traffic and commuting patterns 

This factor considers the number of commuters in each county who drive
to another county within the Parkersburg-Marietta area, the percent of
total commuters in each county who commute within the area, as well as
the total Vehicle Miles Traveled (VMT) for each county in millions of
miles (see Table 5).  A county with numerous commuters is generally an
integral part of an urban area and is likely contributing to fine
particle concentrations in the area.  

Table 5.  Traffic and Commuting Patterns

County	State Recommended Nonattainment?	2005 VMT

(106 mi)	Number Commuting to any violating counties 	Percent

Commuting to any violating counties 	Number Commuting within/to
statistical area 	Percent

Commuting within/to statistical area 

Wood, WV	No	        976 	31,700 	85 	      35,720 	          96 

Washington, OH	Yes	        686 	5,930 	21 	      26,250 	          94 

Pleasants, WV	No	          67 	640 	22 	        2,460 	          86 

Athens, OH	No	        480 	560 	2 	        1,030 	            4 

Jackson, WV	No	        444 	610 	6 	           690 	            6 

Meigs, OH	No	        186 	290 	3 	           630 	            7 

The listing of counties on Table 4 reflects a ranking based on the
number of people commuting within or to the Parkersburg-Marietta
statistical area.  The counties that are in the nonattainment area for
the 1997 PM2.5 NAAQS are shown in boldface.  The percent commuting
within the Parkersburg area information indicates that Washington,
Pleasants, and Wood Counties are connected.  The small commuting to the
statistical area figures suggests that Athens and Meigs Counties, Ohio
are separate from the Parkersburg-Marietta area.

Note:  The 2005 VMT data used for tables 5 and 6 of the technical
analysis have been derived using methodology such as that described in
"Documentation for the 2005 Mobile National Emissions Inventory, Version
2," December 2008, prepared for the Emission Inventory Group, U.S. EPA. 
This document may be found at:   HYPERLINK
"ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/20
05_mobile_nei_version_2_report.pdf" 
ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/200
5_mobile_nei_version_2_report.pdf .

Factor 5:  Growth rates and patterns  

This factor considers population growth for 2000-2005 and growth in
vehicle miles traveled for 1996-2005 for counties in
Parkersburg-Marietta area, as well as patterns of population and VMT
growth.  A county with rapid population or VMT growth is generally an
integral part of an urban area and likely to be contributing to fine
particle concentrations in the area.

Table 6 below shows population, population growth, VMT, and VMT growth
for counties that are included in the Parkersburg-Marietta area. 
Counties are listed in descending order based on VMT growth between 1996
and 2005.

Table 6.  Population and VMT Growth and Percent Change

County	Population (2005)	Population % change (2000-05)	2005 VMT

(106 mi)	VMT

% change

(1996-05)

Pleasants, WV	       7,329 	-2	          67 	          37 

Wood, WV	     86,881 	-1	        976 	          11

Athens, OH	     62,028 	0 	        480 	            3 

Meigs, OH	     23,179 	1 	        186 	            0 

Washington, OH	     62,155 	-2	        686 	          -1 

Jackson, WV	     28,306 	1 	        444 	           -7

There was little population change for the counties.  This is not the
case for VMT change.  The West Virginia counties, Pleasants and Wood
Counties, had solid increases in VMT between 1996 and 2005.  Washington
County, Ohio had a slight decline in its VMT.  The Ohio counties near
the area showed little or no VMT growth.

Factor 6:  Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service
instruments and other meteorological monitoring sites in the area.  Wind
direction and wind speed data for 2005-2007 were analyzed, with an
emphasis on “high PM2.5 days” for each of two seasons, an
October-April “cold” season and a May-September “warm” season. 
These high days are defined as days where any FRM or FEM air quality
monitors had 24-hour PM2.5 concentrations above 95% on a frequency
distribution curve of PM2.5 24-hour values. 

For each air quality monitoring site, EPA developed a “pollution
rose” to understand the prevailing wind direction and wind speed on
the days with highest fine particle concentrations.  The figure
identifies 24-hour PM2.5 values by color; days exceeding 35 μg/m3 are
denoted with a red or black icon.  A dot indicates the day occurred in
the warm season; a triangle indicates the day occurred in the cool
season.  The center of the figure indicates the location of the air
quality monitoring site, and the location of the icon in relation to the
center indicates the direction from which the wind was blowing on that
day.  An icon that is close to the center indicates a low average wind
speed on that day.  Higher wind speeds are indicated when the icon is
further away from the center.

The pollution rose for the Parkersburg-Marietta area is provided as
Figure 2.  Winds on high concentration days show a slight tendency to
come from the Northeast or Southwest.  Overall, the winds come from a
variety of directions.  So, it is appropriate to consider counties in
all directions from the violations.

 

Figure 2

Note:  the meteorology factor is also considered in each county’s
Contributing Emissions Score because the method for deriving this metric
included an analysis of trajectories of air masses for high PM2.5 days.

Factor 7:  Geography/topography (mountain ranges or other air basin
boundaries)

The geography/topography analysis evaluates the physical features of the
land that might have an effect on the air shed and, therefore, on the
distribution of PM2.5 over the area.

The Parkersburg-Marietta 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 the decision-making process.

Factor 8:  Jurisdictional boundaries

In evaluating the jurisdictional boundary factor, EPA gave special
consideration to areas that were already designated nonattainment in
2005 for violating the 1997 fine particle standards.  Analysis of
chemical composition data in these areas indicates that the same
components that make up most of the PM2.5 mass in the area on an annual
average basis such as sulfate and direct PM2.5 carbon in many eastern
areas also are key contributors to the PM2.5 mass on days exceeding the
24-hour PM2.5 standard.  These data indicate that in many cities, the
same source categories that contribute to violations of the annual
standard also contribute to exceedances of the 24-hour standard.  

EPA has generally concluded that counties that were designated as having
emissions sources contributing to fine particle concentrations which
exceeded the 1997 standards (all areas violated the annual standard, two
also violated the previous 24-hour standard) also contribute to fine
particle concentrations on the highest days.  For this reason, EPA
believes that for most existing nonattainment areas, the nonattainment
area for the 2006 24-hour standard should be the same.  Consideration
also should be given to existing boundaries and organizations as they
may facilitate air quality planning and the implementation of control
measures to attain the standard.  Areas already designated as
nonattainment represent important boundaries for state air quality
planning.

The Wood-Washington-Wirt Interstate Planning Commission (WWW) is the
Metropolitan Planning Organization (MPO) for the following townships in
Washington County, OH: Newport, Marietta, Fearing, Muskingum, Warren,
Dunham, and Belpre Townships.  WWW website:
http://www.triplew.org/index.html. 

The Parkersburg-Marietta ozone maintenance area consists of the
following counties: Washington County, Ohio, and Wood County, West
Virginia. 

The Parkersburg-Marietta nonattainment area for the 2006 standards is
identical to the nonattainment area designated under the 1997 PM2.5
standards.

Factor 9:  Level of control of emission sources 

Under this factor, the existing level of control of emission sources is
taken into consideration.  The emissions data used by EPA in this
technical analysis and provided in Table 1 under Factor 1 represent
emissions levels taking into account any control strategies implemented
in the Parkersburg-Marietta area before 2005 on stationary, mobile, and
area sources.  Data are presented for PM2.5 components that are directly
emitted, carbonaceous PM2.5 and crustal PM2.5, and for pollutants which
react in the atmosphere to form fine particles such as SO2, NOx, VOC,
and ammonia.  

In considering county-level emissions, EPA used data from the 2005
National Emissions Inventory, the most updated version of the national
inventory available at the beginning of the designations process in late
2007.  However, EPA recognized that for certain counties, emissions may
have changed since 2005.  For example, certain power plants or large
sources of emissions in or near this area may have installed emission
controls or otherwise significantly reduced emissions since 2005.  Some
States provided updated information on emissions and emission controls
in their comments to EPA.  EPA considered such additional information in
making final designation decisions.  

With regard to nearby power plants, EPA considered information about
whether a specific plant installed federally enforceable emission
controls by December 2008 resulting in significant emissions reductions.
 A control requirement is considered to be federally-enforceable if it
is required by a State regulation adopted in a State implementation
plan, if it is included in a federally-enforceable Title V operating
permit, or if it is required by a consent decree which also requires the
controls to be included in federally enforceable permit upon termination
of the consent decree.  In making final decisions, EPA also considered
whether a facility would continue to emit pollutants which contribute to
PM2.5 exceedances even after emission controls are operational. 

Ohio did not provide other information regarding other power plants or
any other large sources in the Parkersburg-Marietta area.

EPA Technical Analysis for Steubenville-Weirton, Ohio-West Virginia 

The Steubenville-Weirton nonattainment area designated for the 1997
standards is comprised of three counties: Jefferson County, Ohio, and
Brooke and Hancock Counties, West Virginia.  Violations of the 2006
standards have been monitored in all three of these counties.  Ohio
recommended Jefferson County to be nonattainment under the 2006
standards in its December 17, 2007 letter.

EPA agreed with Ohio’s recommendation.  The emissions from Jefferson
County, Ohio, especially sulfur dioxide, are high.  There are two power
plants in Jefferson County that contribute to the high emissions. 
Emission controls have been added at some units of the Cardinal plant,
but SO2 emission controls at the remaining unit at Cardinal and at the
several units at the Sammis plant are not expected to be installed until
2010 or later.  Thus, Jefferson County emissions remain large, and
continue to contribute to violations in this area

The Steubenville area is relatively near to the Pittsburgh area. 
However, EPA believes that these two areas are sufficiently distinct to
warrant treatment as separate nonattainment areas.  

Other counties around the Steubenville-Weirton area have relatively low
emissions.  No other factor warrants inclusion of any additional Ohio
county in the Steubenville-Weirton nonattainment area.

Figure 1 is a map of the counties in the nonattainment area and other
relevant information such as the locations and design values of air
quality monitors, and the metropolitan area boundary. 

 Figure 1

For this area, EPA previously established PM2.5 nonattainment boundaries
for the 1997 PM2.5 NAAQS that included three counties including
Jefferson County, Ohio.  

In its December 17, 2007 letter, Ohio recommended the same Ohio counties
be designated as “nonattainment” for the 2006 24-hour PM2.5 standard
based on air quality data from 2004-2006.  These data are from Federal
Reference Method (FRM) monitors located in the state.

In August 2008, EPA notified Ohio of its intended designations.  In this
letter, EPA also requested that if the State wished to provide comments
on EPA’s intended designation, it should do so by October 20, 2008. 
EPA stated that it would consider any additional information (e.g., on
power plants or partial county areas) provided by the state in making
final decisions on the designations.  

Based on EPA's technical analysis described below, EPA designated one
Ohio county and two West Virginia counties as nonattainment for the
24-hour PM2.5 air-quality standard as part of the Steubenville
nonattainment area, based upon currently available information.

The following is a review of data for relevant factors for the EPA
Region 5 portion of the Steubenville-Weirton, Ohio-West Virginia area. 

Factor 1:  Emissions data

For this factor, EPA evaluated county level emission data for the
following PM2.5 components and precursor pollutants:  “PM2.5 emissions
total,” “PM2.5 emissions carbon,” “PM2.5 emissions other,”
“SO2,” “NOx,” “VOCs,” and “NH3.”  “PM2.5 emissions
total” represents direct emissions of PM2.5 and includes: “PM2.5
emissions carbon,” “PM2.5 emissions other”, primary sulfate (SO4),
and primary nitrate.  (Although primary sulfate and primary nitrate,
which are emitted directly from stacks rather than forming in
atmospheric reactions with SO2 and NOx, are part of “PM2.5 emissions
total,” they are not shown in Table 1 as separate items).  “PM2.5
emissions carbon” represents the sum of organic carbon (OC) and
elemental carbon (EC) emissions, and “PM2.5 emissions other”
represents other inorganic particles (crustal).  Emissions of SO2 and
NOx, which are precursors of the secondary PM2.5 components sulfate and
nitrate, are also considered.  VOCs (volatile organic compounds) and NH3
(ammonia) are also potential PM2.5 precursors and are included for
consideration. 

Emissions data were derived from the 2005 National Emissions Inventory
(NEI), version 1.  See
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

EPA also considered the Contributing Emissions Score (CES) for each
county.  The CES is a metric that takes into consideration emissions
data, meteorological data, and air quality monitoring information to
provide a relative ranking of counties in and near an area.  Note that
this metric is not the exclusive manner for considering data for these
factors.  A more detailed description can be found at
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html#C.

Table 1 shows emissions of PM2.5 and precursor pollutants components
(given in tons per year) and the CES for violating and potentially
contributing counties in the Steubenville area.  Counties that are part
of the Steubenville nonattainment area for the 1997 PM2.5 NAAQS are
shown in boldface.  Counties are listed in descending order by CES.

Table 1.  PM2.5 24-hour Component Emissions, and CESs 

County	State Recommended Nonattainment?	CES	PM2.5

emissions 

total	PM2.5

emissions 

carbon	PM2.5

emissions 

other	SO2

	NOx

	VOCs

	NH3

Jefferson, OH	Yes	100	11,409	722	10,686	224,025	46,158	3,693	297

Hancock, WV	Yes	60	3,781	704	3,077	2,039	4,404	2,298	830

Allegheny, PA	Other	27	5,221	2,245	2,975	51,471	63,290	46,690	2,249

Marshall, WV	No	23	4,604	309	4,295	118,021	39,932	3,230	146

Brooke, WV	Yes	19	579	192	388	1,349	2,131	3,436	210

Jefferson County, Ohio has the highest emissions in the area.  The
emissions of direct PM2.5, sulfur dioxide, and nitrogen oxides are all
large.  Jefferson County also has the highest CES, which indicates it
contributes to the area violations.  Although not shown on this table,
the emissions and CES of other nearby Ohio counties that are not part of
other areas designated nonattainment are low.

Table 2 provides the data for CES weighting factors.  The trajectory
factors are used in CES calculations to account for seasonal
meteorology.  For the top 10% of days in both the cold and warm seasons,
wind trajectories were run for a 48 hour period preceding the high
monitor reading.  The amount of time the air mass was over a county
within the mixing height was calculated.  The values were scaled so that
the maximum value is 100.  Thus, the county that is most likely to be
upwind of a monitor on a high concentration day in a season is given a
score of 100.  The scores for the other counties will reflect the
relative likelihood of being upwind.  As the concentration of a
pollutant will decrease as it goes further downwind, a distance
weighting factor is also used in calculating the CES.  The distance
factor listed on Table 2 provides the distance from the center of a
county to the center of the violating county.  If a county is violating,
the distance used is the average distance from the center to the county
line.

  Table 2.  CES Factor Data

County	CES	Trajectory Factor- Cold	Trajectory Factor- Warm	Distance (mi)

Jefferson	100	76	75	10.8

Hancock	60	76	70	13.1

Brooke	19	98	95	11.4

Allegheny	27	43	33	38.9

Marshall	23	91	95	35

Factor 2:  Air quality data 

This factor considers the 24-hour PM2.5 design values (in µg/m3) for
air quality monitors in counties in the Steubenville area based on data
for the 2005-2007 period.  A monitor’s design value indicates whether
that monitor attains a specified air quality standard.  The 24-hour
PM2.5 standards are met when the 3-year average of a monitor’s 98th
percentile values are 35 µg/m3 or less.  A design value is only valid
if minimum data completeness criteria are met.

The 24-hour PM2.5 design values for counties in the Steubenville area
are shown in Table 3.  Jefferson County, Ohio has a design value which
exceeds the 2006 standards.  The two West Virginia area counties also
violate the air quality standards.  So, all three counties in the
Steubenville area have 2005-2007 design values over the standards.

	Table 3.  Air Quality Data

County	State 

Recommended

 Nonattainment?	Design Values

2004-2006

	Design Values

2005-2007

Jefferson, OH	Yes	43	40

Hancock, WV	Yes	0	41

Brooke, WV	Yes	40	44

For purposes of its review, EPA used data available from the Chemical
Speciation Network and the Interagency Monitoring of Protected Visual
Environments (IMPROVE) network to estimate the composition of fine
particle mass on days with the highest fine particle concentrations. 
Analysis of these data indicates that the days with the highest fine
particle concentrations in the Steubenville-Weirton area occur about 86%
in the warm season and 14% in the cool season.  In the warm season, the
average chemical composition of the highest days is 75% sulfate, no
nitrate, 22% carbon, and 3% crustal.  In the cool season, the average
chemical composition of the highest days is 75% sulfate, no nitrate, 22%
carbon, and 3% crustal.  These data indicate that sources of SO2, NOx,
and direct PM2.5 emissions contribute to violations in the area.

Factor 3: Population density and degree of urbanization (including
commercial development)

Table 4 shows the 2005 population for each county in the area being
evaluated, as well as the population density for each county in that
area.  Population data gives an indication of whether it is likely that
population-based emissions might contribute to violations of the 24-hour
PM2.5 standards. 

Table 4.  Population

County	State Recommended Nonattainment?	2005 Population	2005 Population
Density (pop/sq mi)

Jefferson, OH	Yes	     70,631 	172

Hancock, WV	Yes	     31,191 	354

Brooke, WV	Yes	     24,474 	265

Jefferson County, Ohio has a well larger population that both Brooke and
Hancock Counties in West Virginia.  However, the West Virginia counties
are smaller in land area which gives both counties population densities
larger that the Jefferson County population density.

Factor 4: Traffic and commuting patterns 

This factor considers the number of commuters in each county who drive
to another county within the Steubenville area, the percent of total
commuters in each county who commute within the area, as well as the
total Vehicle Miles Traveled (VMT) for each county in millions of miles
(see Table 5).  A county with numerous commuters is generally an
integral part of an urban area and is likely contributing to fine
particle concentrations in the area.  

Table 5.  Traffic and Commuting Patterns

County	State Recommended Nonattainment?	2005 VMT

(106 mi)	Number Commuting to any violating counties 

	Percent

Commuting to any violating counties 

	Number Commuting into statistical area 	Percent

Commuting into statistical area 

Jefferson, OH	Yes	        684 	24,330 	85 	             -   	          -
  

Hancock, WV	Yes	        187 	12,820 	91 	             -   	          -  

Brooke, WV	Yes	        210 	9,320 	89 	             -   	          -   

The listing of counties on Table 5 reflects a ranking based on the
number of people commuting to violating counties.  The commuting in the
statistical area figures were not available in the Steubenville-Weirton
area.  All listed counties are in the nonattainment area for the 1997
PM2.5 NAAQS.  All three area counties are in violation of the air
quality standards, so commuting to any area county is commuting to a
violating county.  All three Steubenville area counties have a fair
percent of commuting to violating counties.

Note:  The 2005 VMT data used for tables 5 and 6 of the technical
analysis have been derived using methodology such as that described in
"Documentation for the 2005 Mobile National Emissions Inventory, Version
2," December 2008, prepared for the Emission Inventory Group, U.S. EPA. 
This document may be found at:   HYPERLINK
"ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/20
05_mobile_nei_version_2_report.pdf" 
ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/200
5_mobile_nei_version_2_report.pdf .

Factor 5:  Growth rates and patterns  

This factor considers population growth for 2000-2005 and growth in
vehicle miles traveled for 1996-2005 for counties in Steubenville area,
as well as patterns of population and VMT growth.  A county with rapid
population or VMT growth is generally an integral part of an urban area
and likely to be contributing to fine particle concentrations in the
area.

Table 6 below shows population, population growth, VMT, and VMT growth
for counties that are included in the Steubenville area.  Counties are
listed in descending order based on VMT growth between 1996 and 2005.

Table 6.  Population and VMT Growth and Percent Change

County	Population (2005)	Population % change (2000-2005)	2005 VMT

(106 mi)	VMT

% change

(1996-2005)

Brooke, WV	     24,474 	-4	        210 	            0 

Jefferson, OH	     70,631 	-4	        684 	           -6

Hancock, WV	     31,191 	-4	        187 	         -32

Jefferson County, Ohio joined the West Virginia counties in experiencing
a population decline from 2000 to 2005.  The VMT declined in Jefferson
County, but not nearly as sharply as the 32% decline in Hancock County,
West Virginia.  The VMT was unchanged for Brooke County, West Virginia
for the 1996 to 2005 period.

Factor 6:  Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service
instruments and other meteorological monitoring sites in the area.  Wind
direction and wind speed data for 2005-2007 were analyzed, with an
emphasis on “high PM2.5 days” for each of two seasons, an
October-April “cold” season and a May-September “warm” season. 
These high days are defined as days where any FRM or FEM air quality
monitors had 24-hour PM2.5 concentrations above 95% on a frequency
distribution curve of PM2.5 24-hour values. 

For each air quality monitoring site, EPA developed a “pollution
rose” to understand the prevailing wind direction and wind speed on
the days with highest fine particle concentrations.  The figure
identifies 24-hour PM2.5 values by color; days exceeding 35 μg/m3 are
denoted with a red or black icon.  A dot indicates the day occurred in
the warm season; a triangle indicates the day occurred in the cool
season.  The center of the figure indicates the location of the air
quality monitoring site, and the location of the icon in relation to the
center indicates the direction from which the wind was blowing on that
day.  An icon that is close to the center indicates a low average wind
speed on that day.  Higher wind speeds are indicated when the icon is
further away from the center.

The pollution rose for the Steubenville area is provided as Figure 2. 
Winds on high concentration days show a tendency to come from the
Southwest to Southeast.  There are several large sources in the
Steubenville area generally South of Brooke County, West Virginia, where
the pollution rose was based.  Overall, the winds come from a variety of
directions.  So, it is appropriate to consider counties in all
directions from the violations.

 

Figure 2

Note:  the meteorology factor is also considered in each county’s
Contributing Emissions Score because the method for deriving this metric
included an analysis of trajectories of air masses for high PM2.5 days.

Factor 7:  Geography/topography (mountain ranges or other air basin
boundaries)

The geography/topography analysis evaluates the physical features of the
land that might have an effect on the air shed and, therefore, on the
distribution of PM2.5 over the area.

The Steubenville 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 the
decision-making process.

Factor 8:  Jurisdictional boundaries

In evaluating the jurisdictional boundary factor, EPA gave special
consideration to areas that were already designated nonattainment in
2005 for violating the 1997 fine particle standards.  Analysis of
chemical composition data in these areas indicates that the same
components that make up most of the PM2.5 mass in the area on an annual
average basis such as sulfate and direct PM2.5 carbon in many eastern
areas also are key contributors to the PM2.5 mass on days exceeding the
24-hour PM2.5 standard.  These data indicate that in many cities, the
same source categories that contribute to violations of the annual
standard also contribute to exceedances of the 24-hour standard.  

EPA has generally concluded that counties that were designated as having
emissions sources contributing to fine particle concentrations which
exceeded the 1997 standards (all areas violated the annual standard, two
also violated the previous 24-hour standard) also contribute to fine
particle concentrations on the highest days.  For this reason, EPA
believes that for most existing nonattainment areas, the nonattainment
area for the 2006 24-hour standard should be the same.  Consideration
also should be given to existing boundaries and organizations as they
may facilitate air quality planning and the implementation of control
measures to attain the standard.  Areas already designated as
nonattainment represent important boundaries for state air quality
planning.

The Brooke-Hancock-Jefferson Metropolitan Planning Commission (BHJMPC)
is the Metropolitan Planning Organization (MPO) for Jefferson County,
OH.  BHJMPC website: http://www.bhjmpc.org/

The Steubenville-Weirton ozone maintenance area consists of Jefferson
County in Ohio and Brooke and Hancock Counties in West Virginia.  The
Steubenville-Weirton nonattainment area under the 2006 standards is
identical to the nonattainment area designated under the 1997 PM2.5
standard.

Factor 9:  Level of control of emission sources 

Under this factor, the existing level of control of emission sources is
taken into consideration.  The emissions data used by EPA in this
technical analysis and provided in Table 1 under Factor 1 represent
emissions levels taking into account any control strategies implemented
in the Steubenville area before 2005 on stationary, mobile, and area
sources.  Data are presented for PM2.5 components that are directly
emitted, carbonaceous PM2.5 and crustal PM2.5, and for pollutants which
react in the atmosphere to form fine particles such as SO2, NOx, VOC,
and ammonia.  

In considering county-level emissions, EPA used data from the 2005
National Emissions Inventory, the most updated version of the national
inventory available at the beginning of the designations process in late
2007.  However, EPA recognized that for certain counties, emissions may
have changed since 2005.  For example, certain power plants or large
sources of emissions in or near this area may have installed emission
controls or otherwise significantly reduced emissions since 2005.  Some
States provided updated information on emissions and emission controls
in their comments to EPA.  EPA considered such additional information in
making final designation decisions.  

With regard to nearby power plants, EPA considered information about
whether a specific plant installed federally enforceable emission
controls by December 2008 resulting in significant emissions reductions.
 A control requirement is considered to be federally-enforceable if it
is required by a State regulation adopted in a State implementation
plan, if it is included in a federally-enforceable Title V operating
permit, or if it is required by a consent decree which also requires the
controls to be included in federally enforceable permit upon termination
of the consent decree.  In making final decisions, EPA also considered
whether a facility would continue to emit pollutants which contribute to
PM2.5 exceedances even after emission controls are operational. 

Ohio provided information regarding other power plants in Jefferson
County.  Considering the emission control devices currently operating
the emissions remain high.  Additional controls are planned.  The
planned controls may improve the air quality in the future. 
Designations are based on current air quality and information. 
Jefferson County, Ohio has a design value exceeding the standard and it
emissions remain large.

EPA Technical Analysis for Youngstown-Warren-East Liverpool,
Ohio-Pennsylvania 

The Youngstown area is designated attainment under the 1997 standards. 
However, monitoring indicates a violation of the 2006 standards in
Mahoning County, Ohio.  Trumbull County had shown a 2004-2006 violation,
but data indicates it meets the standards in 2005-2007.  There are four
counties in the combined statistical area: Columbiana, Mahoning, and
Trumbull Counties in Ohio and Mercer County, Pennsylvania.  Ohio
originally recommended Mahoning and Trumbull Counties as nonattainment,
although Ohio subsequently recommended that the area be designated
attainment based on 2006 to 2008 data.  EPA analyzed these and other
nearby counties.  Many of the nearby counties are in other metropolitan
areas and thus were evaluated as part of those other areas. 

EPA agrees with the State’s original recommendations.  Within the
Youngstown area, the greatest emissions and the greatest likely local
contribution to the violations in the area are in Mahoning and Trumbull
counties.  Columbiana County emissions are moderate but are
substantially lower than those of Mahoning and Trumbull Counties. 
Columbiana County is also excluded from the 8-hour ozone maintenance
area.

EPA is providing an opportunity for states to quality assure, submit,
and certify air quality data for 2008, which may indicate that areas
like the Youngstown area warrant a different designation based on 2006
to 2008 data than EPA is applying based on 2005 to 2007 data.  However,
EPA cannot use 2006 to 2008 data as the basis for designations until
such time and monitoring data for the full year is available, quality
assured, submitted, and certified.  Therefore, for now, EPA must base
the designations it promulgates on 2005 to 2007 data.  Since those data
indicate a violation, EPA must designate the Youngstown area as
nonattainment.

As noted earlier, Youngstown is near several other urban areas,
including Cleveland, Canton, and Steubenville.  However, EPA views these
areas as sufficiently distinct to warrant treatment as separate
nonattainment areas.  Regarding the counties that are not being included
in other nonattainment areas, EPA finds that emissions of these counties
are relatively low, and no other factor warrants their inclusion in the
nonattainment area.

Figure 1 is a map of the counties in the nonattainment area and other
relevant information such as the locations and design values of air
quality monitors, and the metropolitan area boundary. 

 Figure 1

In its December 17, 2007 letter, Ohio recommended the Mahoning and
Trumbull Counties be designated as “nonattainment” for the 2006
24-hour PM2.5 standard based on air quality data from 2004-2006.  These
data are from Federal Reference Method (FRM) monitors located in the
state.

In August 2008, EPA notified Ohio of its intended designations.  In this
letter, EPA also requested that if the State wished to provide comments
on EPA’s intended designation, it should do so by October 20, 2008. 
EPA stated that it would consider any additional information (e.g., on
power plants or partial county areas) provided by the state in making
final decisions on the designations.  In a letter dated October 8, 2008,
Ohio revised its recommendation based on consideration of 2008 data.

Based on EPA's technical analysis described below, EPA is designating
two Ohio counties as nonattainment for the 24-hour PM2.5 air-quality
standard as part of the Youngstown nonattainment area, based upon
currently available information.  

The following is a review of data for relevant factors for the Ohio
portion of the Youngstown, Ohio-Pennsylvania area. 

Factor 1:  Emissions data

For this factor, EPA evaluated county level emission data for the
following PM2.5 components and precursor pollutants:  “PM2.5 emissions
total,” “PM2.5 emissions carbon,” “PM2.5 emissions other,”
“SO2,” “NOx,” “VOCs,” and “NH3.”  “PM2.5 emissions
total” represents direct emissions of PM2.5 and includes: “PM2.5
emissions carbon,” “PM2.5 emissions other”, primary sulfate (SO4),
and primary nitrate.  (Although primary sulfate and primary nitrate,
which are emitted directly from stacks rather than forming in
atmospheric reactions with SO2 and NOx, are part of “PM2.5 emissions
total,” they are not shown in Table 1 as separate items).  “PM2.5
emissions carbon” represents the sum of organic carbon (OC) and
elemental carbon (EC) emissions, and “PM2.5 emissions other”
represents other inorganic particles (crustal).  Emissions of SO2 and
NOx, which are precursors of the secondary PM2.5 components sulfate and
nitrate, are also considered.  VOCs (volatile organic compounds) and NH3
(ammonia) are also potential PM2.5 precursors and are included for
consideration. 

Emissions data were derived from the 2005 National Emissions Inventory
(NEI), version 1.  See
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html.

EPA also considered the Contributing Emissions Score (CES) for each
county.  The CES is a metric that takes into consideration emissions
data, meteorological data, and air quality monitoring information to
provide a relative ranking of counties in and near an area.  Note that
this metric is not the exclusive manner for considering data for these
factors.  A more detailed description can be found at
http://www.epa.gov/ttn/naaqs/pm/pm25_2006_techinfo.html#C.

Table 1 shows emissions of PM2.5 and precursor pollutants components
(given in tons per year) and the CES for violating and potentially
contributing counties in the Youngstown area.  Counties that are part of
the Youngstown nonattainment area for the 1997 PM2.5 NAAQS are shown in
boldface.  Counties are listed in descending order by CES.

Table 1.  PM2.5 24-hour Component Emissions, and CESs 

County	State Recommended Nonattainment?	CES	PM2.5

emissions 

total	PM2.5

emissions 

carbon	PM2.5

emissions 

other	SO2

	NOx

	VOCs

	NH3

Jefferson, OH	Other	100	11,409	722	10,686	224,025	46,158	3,693	297

Trumbull, OH	Yes	89	1,730	625	1,105	18,501	13,373	12,098	881

Beaver, PA	Other	43	2,909	451	2,457	45,452	33,400	7,424	450

Lawrence, PA	Other	40	2,046	313	1,733	22,900	9,001	4,234	692

Mahoning, OH	Yes	34	722	338	384	1,927	10,086	10,416	1,415

Portage, OH	Other	18	1,011	496	514	548	7,269	8,365	564

Columbiana, OH	No	14	805	366	441	525	4,377	4,933	1,956

Mercer, PA	No	11	793	290	503	1,042	6,010	7,028	1,210

Mahoning and Trumbull Counties have the highest emissions and CES in the
Youngstown area.  The table indicates counties recommended as
nonattainment for other areas have CES in the same range as Mahoning and
Trumbull Counties.  However, Jefferson County is in Steubenville-Weirton
area.  Beaver and Lawrence Counties in Pennsylvania are in the
Pittsburgh area and Portage County, Ohio is in the Cleveland area. 
Within the Youngstown area, the emissions and CES from Columbiana
County, Ohio and Mercer County, Pennsylvania are substantially smaller
than Mahoning and Trumbull Counties.  

Table 2 provides the data for CES weighting factors.  The trajectory
factors are used in CES calculations to account for seasonal
meteorology.  For the top 10% of days in both the cold and warm seasons,
wind trajectories were run for a 48 hour period preceding the high
monitor reading.  The amount of time the air mass was over a county
within the mixing height was calculated.  The values were scaled so that
the maximum value is 100.  Thus, the county that is most likely to be
upwind of a monitor on a high concentration day in a season is given a
score of 100.  The scores for the other counties will reflect the
relative likelihood of being upwind.  As the concentration of a
pollutant will decrease as it goes further downwind, a distance
weighting factor is also used in calculating the CES.  The distance
factor listed on Table 2 provides the distance from the center of a
county to the center of the violating county.  If a county is violating,
the distance used is the average distance from the center to the county
line.

  Table 2.  CES Factor Data

County	CES	Trajectory Factor- Cold	Trajectory Factor- Warm	Distance (mi)

Jefferson, OH	100	41	80	44.2

Trumbull, OH	89	88	74	20.7

Beaver, PA	43	56	93	33

Lawrence, PA	40	78	98	23.1

Mahoning, OH	34	100	98	11.3

Portage, OH	18	71	52	25.1

Columbiana, OH	14	76	100	18.2

Mercer, PA	11	60	71	31.8

Factor 2:  Air quality data 

This factor considers the 24-hour PM2.5 design values (in µg/m3) for
air quality monitors in counties in the Youngstown area based on data
for the 2005-2007 period.  A monitor’s design value indicates whether
that monitor attains a specified air quality standard.  The 24-hour
PM2.5 standards are met when the 3-year average of a monitor’s 98th
percentile values are 35 µg/m3 or less.  A design value is only valid
if minimum data completeness criteria are met.

The 24-hour PM2.5 design values for counties in the Youngstown area are
shown in Table 3.  Mahoning County, Ohio is in violation of the 2006
PM2.5 air quality standards.  Trumbull County, Ohio had a 2004-2006
design value above the standard, but its 2005-2007 design value shows it
now meets the standards.  There is no air quality data for Columbiana
County, Ohio and Mercer County, Pennsylvania.  There are violations in
nearby counties that are in other nonattainment areas.  However, the
absence of a violating monitor alone is not a sufficient reason to
eliminate counties as candidates for nonattainment status.  Each county
has been evaluated based on the weight of evidence of the nine factors
and other relevant information.

	Table 3.  Air Quality Data

County	State 

Recommended

 Nonattainment?	Design Values

2004-2006

	Design Values

2005-2007

Trumbull, OH	Yes	36	35

Mahoning, OH	Yes	37	36

Columbiana, OH	No	0	0

Mercer, PA	No

Jefferson, OH	Other	43	40

Beaver, PA	Other	45	43

Lawrence, PA	Other	0	0

Portage, OH	Other	34	35

For purposes of its review, EPA used data available from the Chemical
Speciation Network and the Interagency Monitoring of Protected Visual
Environments (IMPROVE) network to estimate the composition of fine
particle mass on days with the highest fine particle concentrations. 
Analysis of these data indicates that the days with the highest fine
particle concentrations in the Youngstown area occur about 63% in the
warm season and 38% in the cool season.  In the warm season, the average
chemical composition of the highest days is 70% sulfate, no nitrate, 24%
carbon, and 6% crustal.  In the cool season, the average chemical
composition of the highest days is 26% sulfate, 29% nitrate, 37% carbon,
and 7% crustal.  These data indicate that sources of SO2, NOx, and
direct PM2.5 emissions contribute to violations in the area.

Factor 3: Population density and degree of urbanization (including
commercial development)

Table 4 shows the 2005 population for each county in the area being
evaluated, as well as the population density for each county in that
area.  Population data gives an indication of whether it is likely that
population-based emissions might contribute to violations of the 24-hour
PM2.5 standards. 

Table 4.  Population

County	State Recommended Nonattainment?	2005 Population	2005 Population
Density (pop/mi2)

Trumbull, OH	Yes	    218,672 	345

Mahoning, OH	Yes	    253,181 	599

Columbiana, OH	No	    110,636 	207

Mercer, PA	No	    119,115 	175

Jefferson, OH	Other	     70,631 	172

Beaver, PA	Other	    176,825 	399

Lawrence, PA	Other	     92,412 	255

Portage, OH	Other	    155,150 	307

Mahoning and Trumbull Counties are the largest counties in the area. 
Columbiana and Mercer Counties each have about half the population of
the larger two counties.  The population density statistics reinforce
this as Mahoning and Trumbull Counties densities are well larger that
the densities of Columbiana and Mercer Counties.

Factor 4: Traffic and commuting patterns 

This factor considers the number of commuters in each county who drive
to another county within the Youngstown area, the percent of total
commuters in each county who commute within or to the area, as well as
the total Vehicle Miles Traveled (VMT) for each county in millions of
miles (see Table 5).  A county with numerous commuters is generally an
integral part of an urban area and is likely contributing to fine
particle concentrations in the area.  

Table 5.  Traffic and Commuting Patterns

County	State Recommended Nonattainment?	2005 VMT

(106 mi)	Number Commuting to any violating counties	Percent

Commuting to any violating counties 	Number Commuting within/to
statistical area 	Percent

Commuting within/to statistical area 

Mahoning, OH	Yes	    2,666 	99,310 	91 	    100,200 	          92 

Trumbull, OH	Yes	    2,153 	85,820 	88 	      85,870 	          88 

Mercer, PA	No	    1,302 	44,370 	87 	      44,270 	          87 

Columbiana, OH	No	       872 	16,360 	33 	      39,050 	          79 

Lawrence, PA	Other	       769 	7,390 	18 	        4,730 	          12 

Portage, OH	Other	    1,788 	35,070 	45	2,250	3

Beaver, PA	Other	    1,522 	48,250 	60 	           970 	            1 

Jefferson, OH	Other	       684 	21,140 	74 	           730 	           
3 

Ashtabula, OH	No	    1,182 	720 	2 	           670 	            2 

Stark, OH	Other	    3,049 	141,890 	80 	        1,980 	            1 

The listing of counties on Table 5 reflects a ranking based on the
number of people commuting to other counties.  The four Youngstown area
counties have a fair amount of commuting within the statistical area. 
Columbiana County, Ohio has a moderate amount of commuting to any
violating county.  The other three Youngstown area counties have more
workers commuting to and a higher percent of commuting into any
violating county.  There is little commuting from other Ohio counties
into the Youngstown area.  This includes the minimal commuting from
Ashtabula and Stark Counties which are adjacent to the Youngstown area. 
Thus, these data support treating Canton and Cleveland as separate urban
areas.

Note:  The 2005 VMT data used for tables 5 and 6 of the technical
analysis have been derived using methodology such as that described in
"Documentation for the 2005 Mobile National Emissions Inventory, Version
2," December 2008, prepared for the Emission Inventory Group, U.S. EPA. 
This document may be found at:   HYPERLINK
"ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/20
05_mobile_nei_version_2_report.pdf" 
ftp://ftp.epa.gov/EmisInventory/2005_nei/mobile_sector/documentation/200
5_mobile_nei_version_2_report.pdf .

Factor 5:  Growth rates and patterns  

This factor considers population growth for 2000-2005 and growth in
vehicle miles traveled for 1996-2005 for counties in Youngstown area, as
well as patterns of population and VMT growth.  A county with rapid
population or VMT growth is generally an integral part of an urban area
and likely to be contributing to fine particle concentrations in the
area.

Table 6 below shows population, population growth, VMT, and VMT growth
for counties that are included in the Youngstown area.  Counties are
listed in descending order based on VMT growth between 1996 and 2005.

Table 6.  Population and VMT Growth and Percent Change

County	Population (2005)	Population % change (2000-05)	2005 VMT

(106 mi)	VMT

% change

(1996-2005)

Mahoning, OH	    253,181 	-2	     2,666 	            9 

Trumbull, OH	    218,672 	-3	     2,153 	            8 

Portage, OH	    155,150 	2 	     1,788 	            6 

Mercer, PA	    119,115 	-1	     1,302 	            0

Beaver, PA	    176,825 	-2	     1,522 	            0 

Lawrence, PA	     92,412 	-2	        769 	           -1

Columbiana, OH	    110,636 	-1	        872 	           -2

Jefferson, OH	     70,631 	-4	        684 	           -6

The population for most counties near Youngtown has been slightly
declining from 2000 to 2005.  The exception is a 2% population gain in
Portage County, Ohio.  Mahoning and Trumbull Counties, Ohio had the
highest VMT growth in the area.  Portage County, Ohio, in the Cleveland
area, also had VMT growth.  The other counties had either no change or a
decrease in VMT during the 1996-2005 period.

Factor 6:  Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service
instruments and other meteorological monitoring sites in the area.  Wind
direction and wind speed data for 2005-2007 were analyzed, with an
emphasis on “high PM2.5 days” for each of two seasons, an
October-April “cold” season and a May-September “warm” season. 
These high days are defined as days where any FRM or FEM air quality
monitors had 24-hour PM2.5 concentrations above 95% on a frequency
distribution curve of PM2.5 24-hour values. 

For each air quality monitoring site, EPA developed a “pollution
rose” to understand the prevailing wind direction and wind speed on
the days with highest fine particle concentrations.  The figure
identifies 24-hour PM2.5 values by color; days exceeding 35 μg/m3 are
denoted with a red or black icon.  A dot indicates the day occurred in
the warm season; a triangle indicates the day occurred in the cool
season.  The center of the figure indicates the location of the air
quality monitoring site, and the location of the icon in relation to the
center indicates the direction from which the wind was blowing on that
day.  An icon that is close to the center indicates a low average wind
speed on that day.  Higher wind speeds are indicated when the icon is
further away from the center.

The pollution rose for the Youngstown area is provided as Figure 2. 
Winds on high concentration days show a slight tendency to come from the
South to Southeast.  Pittsburg, Pennsylvania is well to the Southeast
and other nonattainment areas are well to the South.  These areas may be
part of the regional background.  Overall, the winds come from a variety
of directions.  So, it is appropriate to consider counties in all
directions from the violations.

 

Figure 2

Note:  the meteorology factor is also considered in each county’s
Contributing Emissions Score because the method for deriving this metric
included an analysis of trajectories of air masses for high PM2.5 days.

Factor 7:  Geography/topography (mountain ranges or other air basin
boundaries)

The geography/topography analysis evaluates the physical features of the
land that might have an effect on the air shed and, therefore, on the
distribution of PM2.5 over the area.

The Youngstown 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 the
decision-making process.

Factor 8:  Jurisdictional boundaries

In evaluating the jurisdictional boundary factor, EPA gave special
consideration to areas that were already designated nonattainment in
2005 for violating the 1997 fine particle standards.  However, this area
was designated attainment for the 1997 standards, so nonattainment area
boundaries for the 1997 standards were not a factor in determining this
area’s boundaries.

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㜀$␸䠀$摧泑UᔀThe Eastgate Regional Council of Governments
(Eastgate) is the Metropolitan Planning Organization (MPO) for Mahoning
and Trumbull Counties in Ohio.  The Eastgate webpage is found at  
HYPERLINK "http://www.eastgatecog.org/"  http://www.eastgatecog.org/ . 
The Northeast Ohio Area wide Coordinating Agency (NOACA) is the
Cleveland MPO for Cuyahoga, Geauga, Lake (Ohio), Lorain, and Medina
Counties.

The Youngstown ozone maintenance area consists of Columbiana, Mahoning,
and Trumbull in Ohio and Mercer in Pennsylvania.

Factor 9:  Level of control of emission sources 

Under this factor, the existing level of control of emission sources is
taken into consideration.  The emissions data used by EPA in this
technical analysis and provided in Table 1 under Factor 1 represent
emissions levels taking into account any control strategies implemented
in the Youngstown area before 2005 on stationary, mobile, and area
sources.  Data are presented for PM2.5 components that are directly
emitted, carbonaceous PM2.5 and crustal PM2.5, and for pollutants which
react in the atmosphere to form fine particles such as SO2, NOx, VOC,
and ammonia.  

In considering county-level emissions, EPA used data from the 2005
National Emissions Inventory, the most updated version of the national
inventory available at the beginning of the designations process in late
2007.  However, EPA recognized that for certain counties, emissions may
have changed since 2005.  For example, certain power plants or large
sources of emissions in or near this area may have installed emission
controls or otherwise significantly reduced emissions since 2005.  Some
States provided updated information on emissions and emission controls
in their comments to EPA.  EPA considered such additional information in
making final designation decisions.  

With regard to nearby power plants, EPA considered information about
whether a specific plant installed federally enforceable emission
controls by December 2008 resulting in significant emissions reductions.
 A control requirement is considered to be federally-enforceable if it
is required by a State regulation adopted in a State implementation
plan, if it is included in a federally-enforceable Title V operating
permit, or if it is required by a consent decree which also requires the
controls to be included in federally enforceable permit upon termination
of the consent decree.  In making final decisions, EPA also considered
whether a facility would continue to emit pollutants which contribute to
PM2.5 exceedances even after emission controls are operational. 

Ohio did not provide other information regarding power plants or any
other large sources in the Youngstown area.

 EPA designated nonattainment areas for the 1997 fine particle standards
in 2005.  In 2006, the 24-hour PM2.5 standard was revised from 65
micrograms per cubic meter (average of 98th percentile values for 3
consecutive years) to 35 micrograms per cubic meter; the level of the
annual standard for PM2.5 remained unchanged at 15 micrograms per cubic
meter (average of annual averages for 3 consecutive years).