1 

### Illinois Area Designations f or the

20 08 Ozone National Ambient Air Q uality Standard s

The t able below identifies the areas and associated counties or parts of counties in Illinois that EPA intends to designate as no n attain ment for the 2008 o zone national ambient air quality standard s (20 08 NAAQS)

. In accordance with section 107(d) of the Clean Air Act, EPA must designate a n area ( county

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

violation of the 2008 ozone NAAQS in a nearby area. The technical analyses supporting the boundaries

fo r th is nonattainment area are provided below.

Table 1. Intended Nonattainment Areas in Illinois

Area Illinois’ Recommended

Nonattainment Counties EPA’s Intended N onattainment

Counties

St. Louis

- St Charles

Farmington, MO

- IL* Madison County Monroe County St. Clair County Madison County Monroe County St. Clair County

St. Louis

- St. Charles

- Farmington, MO

- IL is a multi

- state nonattainment area. Table 2 below identifi es the counties in Missouri that EPA intends to designate as part of the nonattainment area

.

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

“ unclassifiable/ attainment ” for the 20 08 ozone NAAQS

.

The analysis below provides the basis for intended nonattainment area boundar ies . It relies on our analysis of whether and which monitors are violating the 20 08 o zone NAAQS

, based on certified air quality monitoring data from 2008

- 2010 and an evaluat ion of w hether nearby areas are contributing to

such violations. 1 EPA has evaluated contribution s from nearby areas based on a weight of evidence analysis considering the factors identified below. EPA issued guidance on December 4, 2008

, that

identified these fa ctors as ones EPA would consider in determining nonattainment area boundaries and

recommend ed that s tates consider these factors in making their designations recommendations to EPA

. 2

1. A ir quality data ( including the design value calculated for each Fede ral Reference Method ( FRM ) or Federal Equivalent Method ( FEM ) monitor in the area ) ; 2. Emissions and emissions

- related data ( including location of sources and population , amount of

emissions and emissions controls , and urban growth patterns) ; 3. M eteorology (wea ther/transport patterns) ; 4. G eography and topography (mountain ranges or other basin boundaries) ; 5. J urisdictional boundaries (e.g., counties, air districts, existing nonattainment areas, Indian

country , metropolitan planning organizations (MPOs))

Ground

- leve l ozone is generally not emitted directly into the air, but is created by chemical reactions between oxides of nitrogen (NO x ) and volatile organic compounds (VOC) in the presence of sunlight.

1 On December 7 , 2011 Illinois submitted certified air quality monitoring data for 2011. Given the timing of this submission,

EP A was not able to consider the 2011 data in this Technical Support Document. EPA will evaluate the implications of the 2011 data as soon as possible.

2 The December 4, 2008 guidance memorandum “Area Designations for the 2008 Revised Ozone National Ambient Air Quality Standards” refers to 9 factors. In this technical support document we have grouped the emissions

- related factors together under the heading of “Emissions and Emissions

- Related Data

, ” which results in 5 categories of factors.2 Because NO x and VOC emissions from a broad range of sources ove r a wide area typically contribute to

violations of the ozone standard s , EPA believes it is important to consider whether there are contributing emissions from a broad geographic area. Accordingly, EPA chose to examine the 5 factors with respect

to the la rger of the Combined Statistical Area (CSA) or Core Based Statistical Area (CBSA) associated with the violating monitor(s)

. 3 All data and information used by EPA in this evaluation are the latest available to EPA and/or provided to EPA by states or tribes.

In EPA’s designations guidance for the 2008 ozone NAAQS 4 EPA recommend ed examining

CSA/C B SA s because certain factors used to establish CSAs and C B SAs are similar to the factors EPA is using in this technical analysis to determine if a nearby area is cont ributing to a violation of the 20 08

o zone NAAQS

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

for the 1

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

1997 o zone NAAQS. Where a violating monitor is not located in a CSA or C B S A, EPA ’s guidance

recommend ed using the boundary of the county containing the violating monitor as the starting point for considering the nonattainment area’s boundary.

Technical A nalysis for St. Louis

- St. Charles

- Farmington, MO

- IL

Figure 1 is a map of the St. Louis

- St. Charles

- Farmington, MO

- IL intended nonattainment area . The

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

monitors , county and o ther jurisdictional boundaries, St. Louis

- St. Charles

- Farmington, MO

- IL CSA boundary, existing nonattainment boundary for 1997 ozone NAAQS

, and major transportation arteries

.

3 Lists of CBSAs and CSAs and their geographic components are provided at www.census.gov/population/www/metroareas/metrodef.html . The lists are periodically updated by the Office of Management and Budget. EPA used the most recent update, based on 2008 population estimates, issued on December 1, 2009 (OMB Bulletin No. 10

- 02).

4 See Appendix [x] for a copy of the guidance memorandum.3 Figure 1.

For purposes o f the 1997 8

- hour ozone NAAQS, portions of this are a were designated nonattainment. The boundary for the nonattainment area for the 1997 o zone NAAQS included the entire counties of Jersey, Madison, Monroe and St. Clair C ounties in Illinois and St. Louis City and Franklin, Jefferson, St

. Charles and St. Lo uis Counties in Missouri

.

Illinois submitted its designation recommendations in a March 9, 2009

, letter from Douglas P. Scott, Director of the Illinois Environmental Protection Agency

, which included enclosures containing an analysis of data supportin g the States recommendations. In this submission Illinois recommended that Madison, Monroe and St. Clair Counties be designated as “nonattainment” for the 2008 ozone NAAQS

based on air quality data from 2006

- 2008

. Missouri submitted its designation recom mendations in a March 11, 2009 letter from Mark N. Templeton, Director of the Missouri Department of Natural Resources, which included enclosures containing an analysis of data supporting the State’s

recommendations. Missouri revised its recommendations a nd MDNR requested EPA to act on t he

revisions in a letter dated December 5, 2011 . In its updated submittal, Missouri recommended that St. Louis City and Jefferson, St. Charles and St. Louis Counties be designated as “nonattainment” for the 2008 ozone NAAQ S based on air quality data from 2006

- 2008

. These data are from FRM or FEM

monitors sited and operated in accordance with 40 CFR Part 5 8

.4 After considering these recommendation s and b ased on EPA's technical analysis described below, EPA

intends to desi gnate the areas in Illinois and Missouri listed in T able 2 below a s “ nonattainment ” for the

20 08 o zone NAAQS as part of the St. Louis

- St. Charles

- Farmington, MO

- IL multi

- state nonattainment

area

.

Table 2 . State 's Recommended and EPA ’ s Intended Designat ed Nonattainment Counties for St. Louis

St. Charles

- Farmington, MO

- IL Area

. St. Louis

- St. Charles

Farmington, MO

- IL

Area State

- Recommended

Nonattainment Counties EPA Intended

Nonattainment Counties

Illinois Madison County Monroe County St. Clair County Ma dison County Monroe County St. Clair County

Missouri Franklin County Jefferson County St. Charles County St Louis County St Louis City Franklin County Jefferson County St. Charles County St Louis County St Louis City

Factor Assessment



### Factor 1 : Air Q uality D ata

For this factor , we considered 8

- hour o zone design values (in ppm ) for air quality monitors in counties

in the St. Louis

- St. Charles

- Farmington, MO

- IL CSA based on data for the 2008

- 2010 period (i.e., the 2010 design value) , which are the mos t recent years with fully

- certified air quality data

. 5 A monitor’s design value is the metric or statistic that indicates whether that monitor attains a specified air quality

standard. The 2008 o zone NAAQS are met at a monitor when the annual f ourth

- high est daily maximum

8

- hour average concentration, averaged over 3 years is 0.075 ppm or less

. A design value is only valid if minimum data completeness criteria are met. See 40 CFR part 50 App endix P . Where several monitors are located in a county (or a d esignated nonattainment area or maintenance area ), the design

value for the county or area is determined by the monitor with the highest level.

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

Monitor ing Stations (SLAMS) that are sited in accordance with 40 CFR Part 58, Appendix D (Section 4.1) and operating with a federal reference method (FRM) or federal equivalent method (FEM) monitor that meets the requirements of 40 CFR part 58, appendix A. All d ata from a special purpose monitor (SPM) using an FRM or FEM which has operated for more than 24 months is eligible for comparison to the NAAQS unless the monitoring agency demonstrates that the data came from a particular period during which the requireme nts of appendix A (quality assurance requirements) or appendix E (probe and monitoring path siting criteria) were not met.

5 On December 7 , 2011 Illinois submitted certified air quality monitoring data for 2011. Given the timing of this submission, EPA was not able to consider the 2011 data in this Technical Support Document. EPA will evaluate the implications of the 2011 data as soon as possible.5 The 2010 design value s for the o zone NAAQS for counties in the St. Louis

- St. Charles

- Farmington,

MO

- IL CSA are shown in Table 3

.

Table 3 . Air Quality Data for Counties in the St. Louis

- St. Charles

- Farmington, MO

- IL CSA

. County State Recommended

Nonattainment? 2008

- 2010 D esign V alue ( ppb )

Illinois:

Bond County No

Calhoun County No

Clinton County No Jersey Count y No 69 Macoupin County No 66

Madison County Yes 72

Monroe County Yes

St. Clair County Yes 68

Missouiri:

Franklin County Yes

Jefferson County Yes 72

Lincoln County No 72

St. Charles County Yes 77

St. Francois County N o St. Louis County Yes 71 St. Louis City Yes 69

Warren County No Washington County No

St Charles County in Missouri show s a violation of the 2008 o zone NAAQS

, t herefore this county is

inclu ded in the nonattainment area

. A county (or partial county) must also be designated nonattainment

if it contributes to a violation in a nearby area. E ach county without a violating monitor that is located near a county with a violating monitor has been evaluated , as discussed below, based on the fi ve factors to determine whether it contributes to the nearby violation

.



### Factor 2: Emissions and Emissions

- Related Data

EPA evaluated emissions of ozone precursors ( NO x and VOC ) and other emissions

- related data that provide information on areas contri buting to violating monitors.

Emissions Data

EPA evaluated county

- level emission data for NO x and VOC derived from the 200 8 National Emissions Inventory (NEI), version 1.5

. This is the most recently available NEI. (See http://www.epa.gov/ttn/chief/net/2008inventory.html ) Significant emissions levels in a nearby area indicate the potential for the area to contribute to the observed ozone standard violation. Table 4 shows

2008 emissions of NO x and VOC (in tons per year) for all counties in the St. Louis

- St. Charles

Farmington, MO

- IL CSA. This table also indicates which of the counties were recommended to be nonattainment for the 2008 ozone NAAQS by their respective states

.6 Table 4

. Tot al 2008 NO x and VOC Emissions.

County State Recommended

Nonattainment ? NO x (tpy) VOC (tpy)

Illinois:

Bond County No 1,422 1,181

Calhoun County No 607 1,057

Clinton County No 4,409 2,515

J ersey County No 1,125 1,166 Macoupin County No 2 ,286 2,147

Madison County Yes 23,109 12,351

Monroe County Yes 2,410 1,551

St. Clair County Yes 10,804 8,719

Illinois total: 46,172 30,687

Missouri:

Franklin County Yes 14,094 4,939

Jefferson County Yes 11,769 6,729

Lincoln County No 1,855 2,081

St. Charles County Yes 15,894 11,652

St. Francois County No 2,030 2,349

St. Louis County Yes 36,455 41,894 St. Louis City Yes 17,576 14,027

Warren County No 1,749 2,064 Washington Count y No 678 862

Missouri total: 102,100 86,597

Areawide: 148,272 117,284

T he emissions data in Table 4 show that, for Illinois, comparatively high 2008 NOx and VOC

emissions originate in Mad ison and St. Clair Counties

. In 2008, these counties account for 73% of the

NO x emissions and 69% of the VOC emissions for the Illinois portion of the area. Monroe County in

Illinois is located between St

. Clair County in Illinois and Jefferson County in Missouri (see Figure 1)

. Since Jefferson County also has relatively high 2008 NO x and VOC emissions, including Monroe County, Illinois as part of the area designated as nonattainment would maintain a contiguous area. Taken together, in 2008 Madison, Mo nroe and St. Claire Counties account for 79% of the NO x emissions and 74% of the VOC emissions in the Illinois portion of the area and 24% of the NO x emissions and 19% of the VOC emissions for the entire St. Louis

- St. Charles

- Farmington, MO

- IL CSA

.

The V OC and NO x emissions originating in Bond, Calhoun, Clinton, Jersey and Macoupin Counties are significantly smaller than those originating in the higher emitting counties elsewhere in the St. Louis

- St.

Charles

- Farmington, MO

- IL CSA. Taken together, in 2008 these counties account for only 6.6% of the

NO x emissions and 6.9% of the VOC emissions for the St. Louis

- St. Charles

- Farmington, MO

- IL CSA.

Note that the comparative emissions levels in the Missouri portion of the St. Louis

- St. Charles

Farmington, M O

- IL CSA are discussed in the ozone designation technical support document for

Missouri.7 Population D ensity and D egree of U rbanization

EPA evaluated the population and vehicle use characteristics and trends of the area as indicators of the probable loca tion and magnitude of non

- point source emissions . These include ozone

- creating

emissions from on

- road and off

- road vehicles and engines, consumer products, residential fuel combustion, and consumer services. Areas of dense population or commercial develo pment are an indicator of area source and mobile source NO x and VOC emissions. Rapid growth in population or Vehicle Miles Traveled ( VMT ) (see below) in a county on the urban perimeter signifies increasing integration with the core urban area, and indicat es that it may be appropriate to include the area

associated with area source and mobile source emissions as part of the nonattainment area. Table 5

shows the population , population density, and population growth information for each county in the

area.

T able 5 . Population and Growth.

County State

Recommended

Nonattainment? 2010 Population 2010 Population

Density (1000 pop/sq mi) Absolute change in population (2000

- 2010) Population % change

(2000

- 2010)

Illinois:

Bond Co unty No 17,768 0.05 118 +1%

Calhoun County No 5,089 0.02

- 1 0%

Clinton County No 37,762 0.08 2,233 +6%

J ersey County No 22,985 0.06 1,330 +6% Macoupin County No 47,765 0.06

- 1,224

- 2%

Madison County Yes 269,282 0.36 10,165 +4%

Monro e County Yes 32,957 0.08 5,193 +19%

St. Clair County Yes 270,056 0.40 13,852 +5%

Illinois total: 703,664 31,666 +5%

Missouri:

Franklin County Yes 101,492 0.11 7,434 +8%

Jefferson County Yes 218,733 0.33 19,995 +10%

Lincol n County No 52,566 0.08 13,310 +34%

St. Charles County Yes 360,485 0.61 74,322 +26%

St. Francois County No 65,359 0.14 9,615 +17%

St. Louis County Yes 998,954 1.91

- 17,376

- 2% St. Louis City Yes 319,294 4.83

- 27,570

- 8%

Warren County No 32,513 0.07 7,793 +32% Washington County No 25,195 0.03 1,785 +8%

Missouri total: 2,174,591 +4%

Areawide: 2,878,255 0.31 120,974 +4%

Source s : U.S. Census Bureau population estimates for 20 10 as of August 4, 2011

For Illinois, population data show that Madison and St. Clair Counties have comparatively high populations and population densities. This implies that the population

- related NO x and VOC emissions

in these counties are comparatively high. Monroe County in Il linois has the highest population percent change and third highest absolute change in population (behind St

. Clair and Madison Counties) among the Illinois Counties in the CSA. Monroe County is located between St

. Clair County in Illinois and

Jefferson C ounty in Missouri. Since Jefferson County also has relatively high population and8 population density, including Monroe County, Illinois as part of the area designated as nonattainment

would maintain a contiguous area.

Note that the ozone designation tech nical support document for Missouri addresses the population

related emission contributions from the Missouri portion of the St. Louis

- St. Charles

- Farmington, MO

IL CSA

.

Traffic and C ommuting P atterns

EPA evaluated the commuting patterns of residents in the area, as well as the total VMT for each

county . In combination with the population/ population density data and the location of main transportation arteries (see above) , this information helps identify the probable location of non

- point

source emissio ns. A county with high VMT and/or a high num b er of commuters is generally an integral part of an urban area and indicates the presence of motor vehicle emissions that may contribute to ozone

formation that contributes to nonattainment in the area

. Rapid po pulation or VMT growth in a county on the urban perimeter signifies increasing integration with the core urban area, and indicates that th is county should be include d in the ozone nonattainment area , particularly if the VOC and/or NO x emissions in this cou nty ar e a significant portion o f the total emissions in the nonattainment area

.

Table 6 shows traffic and commuting pattern data, including total 200 8 VMT for each county

, number of commuters in each county who drive to another county within the area

, a nd the percent of total commuters in each county who commute to other counties within the area.

Table 6 . Traffic and Commuting Patterns

.

County State

Recommended

Nonattainment? 2008 VMT* (million miles) Number Commuting

to or within any violating counti es** Percent Commuting to or within any violating counties**

Illinois:

Bond County No 284 20 0%

Calhoun County No 40 109 5%

Clinton County No 389 49 0%

J ersey County No 192 125 1% Macoupin County No 415 36 0%

Madison County Yes 2 ,839 1,126 1%

Monroe County Yes 361 84 1%

St. Clair County Yes 2,666 729 1%

Illinois total: 7,186

Missouri:

Franklin County Yes 1,637 776 2%

Jefferson County Yes 1,885 1,337 1%

Lincoln County No 495 5,529 30%

St. Charles County Yes 2,728 70,282 47%

St. Francois County No 548 92 0%

St. Louis County Yes 11,925 13,513 3% St. Louis City Yes 3,450 1,502 1%

Warren County No 525 2,967 25% Washington County No 220 27 0%9 Missouri total: 23,413

Areawide: 30,599 * MOBILE model VMTs are those inputs into the NEI version 1.5.

Fo r Illinois, the VMT data show that VMT levels in Madison and St. Clair Counties are significantly higher than those in the other Illinois counties in the St . Louis

- St. Charles

- Farmington, MO

- IL CSA. When including the VMT from Monroe County, together, these three counties account for 82% of the VMT in the Illinois portion of the St. Louis

- St. Charles

- Farmington, MO

- IL CSA and 19 percent of the

VMT in the ent ire CSA.



### Factor 3 : Meteorology ( Weather/T ransport P atterns)

EPA evaluate d available meteorological data to help determine how meteorological conditions, such as weather, transport patterns and stagnation conditions, would affect the fate and transport o f precursor emissions contributing to ozone formation. EPA examined the frequency distribution of wind directions during the summer by averaging National Weather Service direction

- sorted wind directions for each county for a 30 year period. To apply the results of this data analysis to the St. Louis

- St. Charles

Farmington, MO

- IL CSA, we have considered the wind direction frequencies during the summer months (June

- August) for St. Charles County in Missouri, the only county with a recorded violation of

the 2008 ozone NAAQS (see Table 3). Table 7 shows the summertime 30

- year averaged percentages of wind directions (winds blowing indo the subject county from the specified wind direction sector) for St. Charles County in Missouri.

Table 7. Averaged Summert ime Wind Direction Percentages for St. Charles County, MO

Wind Direction Percentage

North

- Northeast 9.82%

East

- Northeast 7.24%

East

- Southeast 13.66%

South

- Southeast 14.41%

South

- Southwest 20.01%

West

- Southwest 14.64%

West

- Northwest 12.84%

North

- Nor thwest 7.39%

The wind direction percentages show that there is no “ preferred ” wind direction during the summertime. Transport winds can and do blow from all directions into the county with a recorded violation of the 2008 ozone NAAQS. There is, howeve r an indication that winds from the south

- southwest may be slightly more prevalent than winds from other directions during the summertime, and there is a southerly component 62.72% of the time.

The state provided wind direction data for days from 2006 t hrough 2008 when ozone concentration s

w ere greater than 75 ppb at any monitor in the Illinois portion of the St. Louis

- St. Charles

- Farmington,

MO

- IL CSA

. Wind data was taken from Edwardsville in Madison County, IL. This data is presented in Figure 2

.10 Fig ure 2

. Primary Wind Direction Percentages at Edwardsville in Madison County, IL for Days from 2006 Through 2008 When Ozone Concentrations in the Illinois Portion of the St. Louis

- St. Charles

Farmington, MO

- IL CSA Were Greater Than 75ppb

Data in Figure 2 indicate that when considering wind direction at Edwardsville in Madison County, IL for days from 2006 through 2008 when ozone concentrations in the Illinois portion of the St. Louis

- St.

Charles

- Farmington, MO

- IL CSA were greater than 75ppb, prevailing w inds were from the south

southwest through the southeast approximately 40% of the time. Edwardsville is slightly to the east and south of the violating monitor in St. Charles County, Missouri. All of the counties proposed as

nonattainment lie to the sout h of or even with the nonattainment monitor in St. Charles County. As shown in Figure 1, the Illinois counties of Madison, St. Clair and Monroe all border Missouri and thus range from directly south of the violating monitor in St. Charles County, to east of the violating

monitor.11 

### Factor 4 : Geography/ T

opography ( M ountain R anges or O ther A ir B asin B oundaries)

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

. The St. Louis

- St. Charles

- Farmington,

MO

- IL CSA does not have any geographical or topographical barriers significantly limiting air pollution transport within its air shed. Therefore, this factor did not play a significant role in t his evaluation

.



### Factor 5 : Jurisdictional B oundaries

Once we identified the general areas we anticipated including in the nonattainment area, we then

consider ed existing jurisdictional boundaries for the purposes of providing a clearly defined legal

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

enforcement functions for nonattainment areas. Examples of jurisdictional boundaries include existing/prior nonattainment area boundarie s for ozone or other u rban

- scale pollutants, count y lines , air

district boundaries , township boundarie s, areas covered by a metropolitan planning organization, state lines, and Reservation boundarie s

.

The St. Louis, MO

- IL area has previously established nonattainment boundari es associated with the 1

- hour and 1997 8

- hour ozone N AAQS. The portion of the St. Louis

- St. Charles

- Farmington, MO

- IL

CSA that we are intending to designate as nonattainment for the 2008 ozone NAAQS is the same area that we designated as nonattainment und er the 1

- hour NAAQS . Under the 1997 8

- hour ozone NAAQS, Jersey County, IL was also included in the nonattainment area due to a monitored violation of the standard in that county.


### Conclusion

Based on the assessment of factors described above, EPA has p reliminarily concluded that the following

Illinois counties meet the CAA criteria for inclusion in the St. Louis

- St. Charles

- Farmington, MO

- IL

nonattainment area: Madison County, Monroe County, and St. Clair County. This is consistent with the

recommenda tion submitted by Illinois. All three of t hese counties were included in the St. Louis, MO

IL nonattainment area for the 1

- hour ozone NAAQS. Under the 1997 o zone NAAQS , Jersey County, IL

was also included in the nonattainment area due to a monitored viol ation of the NAAQS in that county

. The monitor in Jersey County, IL is currently well below the standard and the other factors do not support inclusion of the county within the St. Louis

- St. Charles

- Farmington, MO

- IL nonattainment area

. The re are no air quality monitor s in Illinois counties indicat ing violation s of the 20 08 o zone NAAQS

based on the 2010 design value s. Madison and St. Clair Counties are nearby counties that do not have violating monitors , but EPA has concluded that these areas contribute to the ozone concentrations in violation of the 2008 ozone NAAQS due to relatively high NO x and VOC emissions and relatively high VMT. Based on 2008 data, Madison County has the second highest NO x emissions and third highest

VOC emissions in the St. Loui s

- St. Charles

- Farmington, MO

- IL CSA, and St

. Clair County has the seventh highest NO x emissions and fifth highest VOC emissions in the St. Louis

- St. Charles

Farmington, MO

- IL CSA. Madison and St. Clair Counties have the second and fourth highest 2008

VMT in the St. Louis

- St. Charles

- Farmington, MO

- IL CSA , respectively . Monroe County, IL does not have especially high emissions or VMT, but it is located between St. Clair County, IL and Jefferson County, MO, both of which have comparatively high emissions an d VMT. We support Illinois’

recommendation that Monroe County should be included as part of the designated nonattainment area as its inclusion will maintain a contiguous area. Comparatively low emissions, population

, and VMT in the remaining Illinois cou nties supports the exclusion of these counties from the recommended ozone

nonattainment area for the 2008 8

- hour ozone NAAQS.